River Valley High School attack

# River Valley High School attack

## Abstract

On 19 July 2021, a thirteen-year old Secondary One male student named Ethan Hun Zhe Kai (Chinese: 韩喆凯; pinyin: Hán Zhékǎi) was struck to death with a combat fire fighting axe at River Valley High School in Boon Lay, Singapore, in an incident which was reportedly unprecedented in the history of Singapore. The killer was a sixteen-year-old Secondary Four male student, who was arrested for Ethan's murder shortly afterwards. The boy was initially charged with murdering Ethan; his charge was eventually reduced to manslaughter on the grounds of diminished responsibility, and he was thus sentenced to jail for 16 years on 1 December 2023.

## Attack and aftermath

On July 14, 2021, the perpeturator took the axe and a knife to school in a badminton racquet bag, which he hid under a sink in the toilet, but failed to follow through with his plan. He tried again on July 19, 2021 where the attack occurred between 11:16 a.m. and 11:44 a.m. local time at a fourth floor toilet in River Valley High School. A group of students encountered the attacker — a sixteen-year-old Secondary Four student — outside the toilet at 11:35 a.m. with a combat fire fighting axe. When the attacker asked them to call the police as he wanted the police to shoot him dead, the students retreated to their classroom and instated a lockdown drill. The attacker then went to a classroom to make the same request, upon which the second group also instated a lockdown. Both groups alerted their teachers.

A teacher confronted the attacker and requested that the fire fighting axe be placed on the floor. The attacker complied with the instruction and was escorted to a meeting room. The victim — a thirteen-year-old, Secondary One male student — was then found dead inside the toilet, having suffered multiple slash wounds allegedly caused by the axe. The victim, who was originally not named due to a gag order, was later identified as Ethan Hun Zhe Kai as the gag order was lifted by the High Court at his parents’ request.

Hun's attacker was subsequently arrested by the Singapore Police Force. The entire school was placed into lockdown until around 3:30 p.m. As the following day was Hari Raya Haji, a public holiday, students returned to the school on 21 July. In the days following the attack, counselling was provided for nearly 540 students and teachers, while personnel from the Ministry of Education took over some classes.

## Perpetrator

According to a statement released by the Singapore Police Force several hours after the incident, preliminary investigations revealed that Hun and his killer are not known to each other." It was also revealed that the perpetrator had previously attempted suicide twice two years before in 2019 and had been remanded in the Institute of Mental Health. He is alleged to have procured the axe used in the attack online. According to Strait Times, he bought a tomahawk axe from a store on March 6, bought a Cold Steel Trench Hawk axe measuring 50cm by 22cm and a sharpener from a second store on March 17, and bought a Morakniv bushcraft stainless steel knife measuring 23.5cm by 4cm from a third store in April that year. According to Channel 8 News, the boy had simply wanted to attack the first person to enter the toilet, and Hun became the first and only victim of the boy before his arrest.

The Secondary Four student, who cannot be named due to Singaporean law on account of his age, was charged with murder on 20 July and remanded at the Complex Medical Centre within Changi Prison for psychiatric evaluation. As a minor, he is protected by the Children and Young Persons Act and cannot be sentenced to death if found guilty of the murder of Hun, but he would be sentenced to life imprisonment instead. Criminal lawyer Peter Fernando was assigned to defend the boy in his trial.

On 10 August, a fresh court order was issued to extend the suspect's period of psychiatric remand by another two weeks. By then, Fernando had been replaced by Diana Ngiam and Sunil Sudheesan. The boy was allowed a phone call with his family three days later. He was further remanded on 24 August 2021 for seven days, even though he had completed his psychiatric evaluations. On 31 August, his case was adjourned to 19 October. No date for his trial was scheduled at present. It was also revealed the suspect had been allowed to meet his family, and that he would be transferred to Changi Prison.

On 30 December 2022, it was reported that the boy remained in remand pending trial, and under the arrangements made between the prison authorities and the boy's lawyer Sunil Sudheesan, the teenager had taken his O-levels as a private candidate while behind bars in November 2022. His case was expected to be heard on 25 January 2023.

On 24 February 2023, as the student (who turned 18 in January) was suffering from clinical depression at the time of the incident, the murder charge against him was reduced to culpable homicide not amounting to murder, an offence which was punishable by life imprisonment or up to twenty years in prison, in addition to caning.

## Trial

The perpetrator of the school attack, who stood trial before the High Court, pleaded guilty to the reduced charge of culpable homicide on 1 December 2023, with the prosecution seeking a sentence of 12 to 16 years' imprisonment, while the defence sought a sentence of five years' imprisonment.

The parents of Ethan Hun, Hun Yew Kwong and Sng Hui Ching, requested for the gag order to be lifted as they wanted their son to be remembered by his name. The defence did not object to their request, and the High Court judge granted their request. Hun's parents also reportedly wrote to the trial judge that they had forgiven their son's killer.

On the same date, Justice Hoo Sheau Peng sentenced the killer to 16 years in prison. Justice Hoo stated that the crime itself carried a "chilling degree" of premeditation, cold logic and planning, and it was "without precedent" that a murder took place within a school environment where a student should feel safe inside, and she stated that regardless of the severity of the perpetrator's psychiatric condition, depression cannot become a "licence to kill or harm others". Ruling that the killer should be held "highly culpable" for the vicious killing of Hun, she agreed with the prosecution to sentence the convict to 16 years behind bars, which was the highest proposed sentence submitted by the prosecution. The jail term was backdated to the date of the convict's arrest on 19 July 2021.

## Appeal

On 1 July 2024, the River Valley High School killer, who was then 19, filed an appeal to the Court of Appeal against his jail term, seeking to reduce the sentence to between eight to ten years' imprisonment. Defence lawyer Sunil Sudheesan argued that his client's mental problems and the mitigating factors of the case should warrant him a jail term lower than the 16 years imposed by the High Court, although the prosecution urged the appellate court to uphold the 16-year jail term as the perpetrator still bore significant responsibility despite his psychiatric condition, since he himself did not seek help earlier to address his condition and had consumed the contents of graphic violence that aggravated his tendency to violence.

## Responses

According to local newspaper The Straits Times, the attack was unprecedented in the history of Singapore. Both Prime Minister Lee Hsien Loong and Minister for Education Chan Chun Sing wrote on Facebook that they were "shocked", while the Ministry of Education and River Valley High School said that they were "deeply saddened" by the incident. President Halimah Yacob opined that "parents, schools and our society are ill-equipped to deal with this situation." Minister for Law and Home Affairs K. Shanmugam said that it was "difficult to even describe the true extent of their (the victim's parents') grief". Several other Cabinet members and local religious leaders also publicly commented on the attack.

The attack sparked concerns over mental health in Singapore. Member of Parliament Patrick Tay questioned the decision to return students to school a day after the attack. Minister for Education Chan Chun Sing defended his decision and replied that the ministry had decided that it was better for the students to grieve together than alone at home. Students were allowed to stay home if they chose.

In a Ministerial Statement, Minister for Education Chan Chun Sing announced on 27 July the removal of Common Last Topics from the GCE N, O and A-Levels, and some topics from the final year examinations "to help ease stress". Measures were also put in place, including having all teachers equipped with enhanced mental health literacy, boosting the number of teacher-counsellors from 700 in 2021 to more than 1,000 several years later, recruiting more school counsellors or redeploying teachers to these roles, resuming CCAs at the secondary and pre-university level due to vaccinations, and dedicating more time to check on students' well-being. Measures to strengthen schools' security will be undertaken without eroding trust in the community. A buddy system was later proposed to be implemented in schools.


Descon

# Descon

## Abstract

Descon Engineering (Descon) (Urdu: ڈیسکون انجینئرنگ) is a Pakistani conglomerate headquartered in Lahore.

This company was first established in 1977, now it has been grown into a diversified group. Today, the company operates as a group in a range of sectors, including engineering, power, and chemicals. The company was founded on 15 December 1977. It operates in the engineering, power and chemical sectors. Descon is the only Pakistani engineering company to be included in the Engineering News-Record (a US magazine) list since 2007.

## History

The company was founded by Abdul Razak Dawood as Design Engineering and Construction Services (Descon) in 1977. The initial capital used for starting this startup was Rs. 3.2 million. From this, they expanded into three sectors and now they are operating in UAE, Qatar, Saudi Arabia, Kuwait, Oman, Iraq and South Africa.

The company got its first contract when Attock Refinery asked to set up a small refinery in 1978. In 1981, they got a bigger four-year project of National Refinery which helped the company to expand.

In 1982, they tried to expand to regional markets, where they helped a Saudi company and afterwards got a small project in Abu Dhabi. By 2018, this company was generating 60% of its income from overseas markets which helped the company grow to be a billion-dollar company.

In 2018, Descon expanded its footprint into South Africa by acquiring 26% of Plant Design and Project Services (PDPS), an engineering firm there.

## Subsidiaries

Descon Engineering operates as part of a wider group of companies, each with a specific area of focus within the engineering and industrial sectors. Some notable subsidiaries include:

- Descon Oxychem Limited (DOL) (founded 2004): A Pakistani chemical company

- Descon Engineering Qatar (LLC) (founded 2002): A Qatari branch of Descon

- Descon Plant Design and Project Services (PDPS): A division of Descon Engineering formed through a strategic acquisition of a 26% stake in a South African PDPS company

- Olayan Descon Industrial Company (ODI) (founded 1981): A joint venture with Olayan Saudi Holding

- Presson Descon International Limited (PDIL)


Leon Sterling

# Leon Sterling

## Abstract

Professor Leon Sterling is a career academic with a distinguished academic record. After completing a PhD at the Australian National University, he worked for 15 years at universities in the UK, Israel and the United States. He returned to Australia as Professor of Computer Science at the University of Melbourne in 1995. He served as Head of the Department of Computer Science and Engineering for 6 years. After stepping down as Head, he took up an industry-sponsored chair becoming the Adacel Professor of Software Innovation and Engineering. In 2010, he moved to Swinburne where he served as Dean of the Faculty of Information and Communication Technologies for 4 years and Pro Vice-Chancellor (Digital Frontiers) for two years. He returned to the University of Melbourne in 2019 where he is a part-time Professor of Software Engineering. He has been a prominent figure in IT in Australia, serving as Head of the Council of Deans of ICT from 2012 to 2014, been on a number of national committees, and been a strong advocate for coding in schools through public lectures, blogs, and committee memberships. His current research is in incorporating emotions in technology development, where motivational models are an essential element.

Professor Sterling is the co-author, along with Ehud Shapiro, of the computer science textbook The Art of Prolog.


Nolan Siegel

# Nolan Siegel

## Abstract

Nolan Siegel (born November 8, 2004) is an American racing driver. He currently competes full-time in the IndyCar Series with Arrow McLaren. In 2024, Siegel won the 24 Hours of Le Mans LMP2 class on his first attempt, with United Autosports. Siegel previously competed in the U.S. F2000 National Championship with DEForce Racing and Indy NXT with HMD Motorsports.

## Early career

### Formula 4 United States Championship

Siegel would join the final round of the 2019 Formula 4 United States Championship held at Circuit of the Americas driving for Jay Howard Driver Development. He finished in the top-10 in both races.

Siegel would return to the championship for the first two rounds of the 2020 season once again driving for Jay Howard Driver Development. He would have a best finish of sixth in his final race.

### USF2000 Championship

On February 13, 2019, it was announced Siegel would compete full-time in the 2019 U.S. F2000 National Championship for Newman Wachs Racing. He would finish 15th in the championship.

Siegel returned to the championship in 2020 and switched teams to drive for Jay Howard Driver Development. He took two podiums at Mid-Ohio and finished 13th in the standings.

In January 2021, it was announced Siegel would return for a third season in 2021 driving for DEForce Racing. He would get his first win in the third race held at New Jersey Motorsports Park. He would finish the season 8th in the standings.

### Indy Pro 2000

During 2021, Siegel would make his Indy Pro 2000 debut at Gateway Motorsports Park driving for DEForce Racing. He would impress by finishing 5th.

DEForce Racing announced Siegel would move up to the series full-time in 2022. At the first round held at St. Petersburg, he would take his maiden win by beating competitor Louis Foster on a late restart. Siegel would dominate the second race held at Barber Motorsports Park starting from pole and leading the race from start to finish. Ultimately, he would end up finishing 4th in the championship due to inconsistency during the middle and latter stages of the season.

### Indy NXT

On September 8, 2022, it was announced Siegel would make his Indy Lights debut at final round held at Laguna Seca driving for HMD Motorsports with Dale Coyne Racing.

Siegel announced in October 2022 he would make the jump up to Indy NXT full-time for 2023, remaining at HMD Motorsports with Dale Coyne Racing. He would finish the season third in points, having won two races and scored a total of five podiums. With this, he also became the season's top rookie.

For the 2024 season, Siegel and HMD reunited for a title assault. At the opening round in St. Petersburg, the Californian scored pole and started out his season with a lights-to-flag victory.

## Sportscar racing career

In 2023, the American took part in the LMP2 class of the Asian Le Mans Series, driving for Inter Europol Competition. Partnering Charles Crews and Christian Bogle, Siegel managed to impress, leading his team to victory at Dubai by passing Charlie Eastwood in the final stint, though two retirements in the four-round season meant a lowly fifth place in the standings. He competed in various other sportscar races throughout the year, notably winning two LMP2 class races in the IMSA SportsCar Championship.

For 2024, Siegel would make his debut at the 24 Hours of Le Mans, pairing up with Oliver Jarvis and Bijoy Garg at United Autosports.

## IndyCar

### Part-time commitments (2024)

On March 5, 2024, it was announced Siegel would compete part-time in the No. 18 Honda entry for Dale Coyne Racing, sharing his seat with Jack Harvey. Siegel would partake in the four events which do not clash with his Indy NXT commitments, including the Indianapolis 500.

On June 7, 2024, it was announced that Siegel would substitute for Agustín Canapino at the upcoming race at Road America following abuse on social media directed at Théo Pourchaire after the two made contact during the Detroit Grand Prix a week prior, with Canapino having taken a "leave of absence".

### Arrow McLaren (2024–)

On June 18, 2024, it was announced that Pourchaire had been dropped by the Arrow McLaren team, with the team signing Siegel in his place. Siegel made his debut with the team at the Monterey Grand Prix, where he struggled throughout the weekend, running in 26th at one point after spinning into the gravel; he took advantage of numerous driver errors to finish in twelfth.

## Racing record

### Career summary

* Season still in progress.

### Complete IMSA SportsCar Championship results

(key) (Races in bold indicate pole position; results in italics indicate fastest lap)

Season still in progress.

### Complete Asian Le Mans Series results

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap)

### American open-wheel racing results

#### U.S. F2000 National Championship

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap) (Races with * indicate most race laps led)

#### Indy Pro 2000 Championship

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap) (Races with * indicate most race laps led)

#### Indy NXT

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap) (Races with indicate a race lap led) (Races with * indicate most race laps led)

#### IndyCar Series

(key) (Races in bold indicate pole position; races in italics indicate fastest lap)

* Season still in progress.


Russian language

# Russian language

## Abstract

Russian is an East Slavic language belonging to the Balto-Slavic branch of the Indo-European language family. It is one of the four extant East Slavic languages, and is the native language of the Russians. It was the de facto and de jure official language of the former Soviet Union. Russian has remained an official language of the Russian Federation, Belarus, Kazakhstan, Kyrgyzstan, and Tajikistan, and is still commonly used as a lingua franca in Ukraine, Moldova, the Caucasus, Central Asia, and to a lesser extent in the Baltic states and Israel.

Russian has over 258 million total speakers worldwide. It is the most spoken native language in Europe, the most spoken Slavic language, as well as the most geographically widespread language of Eurasia. It is the world's seventh-most spoken language by number of native speakers, and the world's ninth-most spoken language by total number of speakers. Russian is one of two official languages aboard the International Space Station, one of the six official languages of the United Nations, as well as the fourth most widely used language on the Internet.

Russian is written using the Russian alphabet of the Cyrillic script; it distinguishes between consonant phonemes with palatal secondary articulation and those without—the so-called "soft" and "hard" sounds. Almost every consonant has a hard or soft counterpart, and the distinction is a prominent feature of the language. Another important aspect is the reduction of unstressed vowels. Stress, which is often unpredictable, is not normally indicated orthographically, though an optional acute accent may be used to mark stress – such as to distinguish between homographic words (e.g. замо́к and за́мок), or to indicate the proper pronunciation of uncommon words or names.

## Classification

Russian is an East Slavic language of the wider Indo-European family. It is a descendant of Old East Slavic, a language used in Kievan Rus', which was a loose conglomerate of East Slavic tribes from the late 9th to the mid-13th centuries. From the point of view of spoken language, its closest relatives are Ukrainian, Belarusian, and Rusyn, the other three languages in the East Slavic branch. In many places in eastern and southern Ukraine and throughout Belarus, these languages are spoken interchangeably, and in certain areas traditional bilingualism resulted in language mixtures such as Surzhyk in eastern Ukraine and Trasianka in Belarus. An East Slavic Old Novgorod dialect, although it vanished during the 15th or 16th century, is sometimes considered to have played a significant role in the formation of modern Russian. Also, Russian has notable lexical similarities with Bulgarian due to a common Church Slavonic influence on both languages, but because of later interaction in the 19th and 20th centuries, Bulgarian grammar differs markedly from Russian.

Over the course of centuries, the vocabulary and literary style of Russian have also been influenced by Western and Central European languages such as Greek, Latin, Polish, Dutch, German, French, Italian, and English, and to a lesser extent the languages to the south and the east: Uralic, Turkic, Persian, Arabic, and Hebrew.

According to the Defense Language Institute in Monterey, California, Russian is classified as a level III language in terms of learning difficulty for native English speakers, requiring approximately 1,100 hours of immersion instruction to achieve intermediate fluency.

## Standard Russian

Feudal divisions and conflicts created obstacles between the Russian principalities before and especially during Mongol rule. This strengthened dialectal differences, and for a while, prevented the emergence of a standardized national language. The formation of the unified and centralized Russian state in the 15th and 16th centuries, and the gradual re-emergence of a common political, economic, and cultural space created the need for a common standard language. The initial impulse for standardization came from the government bureaucracy for the lack of a reliable tool of communication in administrative, legal, and judicial affairs became an obvious practical problem. The earliest attempts at standardizing Russian were made based on the so-called Moscow official or chancery language, during the 15th to 17th centuries. Since then, the trend of language policy in Russia has been standardization in both the restricted sense of reducing dialectical barriers between ethnic Russians, and the broader sense of expanding the use of Russian alongside or in favour of other languages.

The current standard form of Russian is generally regarded as the modern Russian literary language (современный русский литературный язык – "sovremenny russky literaturny yazyk"). It arose at the beginning of the 18th century with the modernization reforms of the Russian state under the rule of Peter the Great and developed from the Moscow (Middle or Central Russian) dialect substratum under the influence of some of the previous century's Russian chancery language.

Prior to the Bolshevik Revolution, the spoken form of the Russian language was that of the nobility and the urban bourgeoisie. Russian peasants, the great majority of the population, continued to speak in their own dialects. However, the peasants' speech was never systematically studied, as it was generally regarded by philologists as simply a source of folklore and an object of curiosity. This was acknowledged by the noted Russian dialectologist Nikolai Karinsky, who toward the end of his life wrote: "Scholars of Russian dialects mostly studied phonetics and morphology. Some scholars and collectors compiled local dictionaries. We have almost no studies of lexical material or the syntax of Russian dialects."

After 1917, Marxist linguists had no interest in the multiplicity of peasant dialects and regarded their language as a relic of the rapidly disappearing past that was not worthy of scholarly attention. Nakhimovsky quotes the Soviet academicians A.M Ivanov and L.P Yakubinsky, writing in 1930:

The language of peasants has a motley diversity inherited from feudalism. On its way to becoming proletariat peasantry brings to the factory and the industrial plant their local peasant dialects with their phonetics, grammar, and vocabulary, and the very process of recruiting workers from peasants and the mobility of the worker population generate another process: the liquidation of peasant inheritance by way of leveling the particulars of local dialects. On the ruins of peasant multilingual, in the context of developing heavy industry, a qualitatively new entity can be said to emerge—the general language of the working class... capitalism has the tendency of creating the general urban language of a given society.

## Geographic distribution

In 2010, there were 259.8 million speakers of Russian in the world: in Russia – 137.5 million, in the CIS and Baltic countries – 93.7 million, in Eastern Europe – 12.9 million, Western Europe – 7.3 million, Asia – 2.7 million, in the Middle East and North Africa – 1.3 million, Sub-Saharan Africa – 0.1 million, Latin America – 0.2 million, U.S., Canada, Australia, and New Zealand – 4.1 million speakers. Therefore, the Russian language is the seventh-largest in the world by the number of speakers, after English, Mandarin, Hindi -Urdu, Spanish, French, Arabic, and Portuguese.

Russian is one of the six official languages of the United Nations. Education in Russian is still a popular choice for both Russian as a second language (RSL) and native speakers in Russia, and in many former Soviet republics. Russian is still seen as an important language for children to learn in most of the former Soviet republics.

### Europe

In Belarus, Russian is a second state language alongside Belarusian per the Constitution of Belarus. 77% of the population was fluent in Russian in 2006, and 67% used it as the main language with family, friends, or at work. According to the 2019 Belarusian census, out of 9,413,446 inhabitants of the country, 5,094,928 (54.1% of the total population) named Belarusian as their native language, with 61.2% of ethnic Belarusians and 54.5% of ethnic Poles declaring Belarusian as their native language. In everyday life in the Belarusian society the Russian language prevails, so according to the 2019 census 6,718,557 people (71.4% of the total population) stated that they speak Russian at home, for ethnic Belarusians this share is 61.4%, for Russians — 97.2%, for Ukrainians — 89.0%, for Poles — 52.4%, and for Jews — 96.6%; 2,447,764 people (26.0% of the total population) stated that the language they usually speak at home is Belarusian, among ethnic Belarusians this share is 28.5%; the highest share of those who speak Belarusian at home is among ethnic Poles — 46.0%.

In Estonia, Russian is spoken by 29.6% of the population, according to a 2011 estimate from the World Factbook, and is officially considered a foreign language. School education in the Russian language is a very contentious point in Estonian politics, and in 2022, the parliament approved a bill to close up all Russian language schools and kindergartens by the school year. The transition to only Estonian language schools and kindergartens will start in the 2024-2025 school year.

In Latvia, Russian is officially considered a foreign language. 55% of the population was fluent in Russian in 2006, and 26% used it as the main language with family, friends, or at work. On 18 February 2012, Latvia held a constitutional referendum on whether to adopt Russian as a second official language. According to the Central Election Commission, 74.8% voted against, 24.9% voted for and the voter turnout was 71.1%. Starting in 2019, instruction in Russian will be gradually discontinued in private colleges and universities in Latvia, and in general instruction in Latvian public high schools. On 29 September 2022, Saeima passed in the final reading amendments that state that all schools and kindergartens in the country are to transition to education in Latvian. From 2025, all children will be taught in Latvian only. On 28 September 2023, Latvian deputies approved The National Security Concept, according to which from 1 January 2026, all content created by Latvian public media (including LSM) should be only in Latvian or a language that "belongs to the European cultural space". The financing of Russian-language content by the state will cease, which the concept says create a "unified information space". However, one inevitable consequence would be the closure of public media broadcasts in Russian on LTV and Latvian Radio, as well as the closure of LSM's Russian-language service.

In Lithuania, Russian has no official or legal status, but the use of the language has some presence in certain areas. A large part of the population, especially the older generations, can speak Russian as a foreign language. However, English has replaced Russian as lingua franca in Lithuania and around 80% of young people speak English as their first foreign language. In contrast to the other two Baltic states, Lithuania has a relatively small Russian-speaking minority (5.0% as of 2008). According to the 2011 Lithuanian census, Russian was the native language for 7.2% of the population.

In Moldova, Russian was considered to be the language of interethnic communication under a Soviet-era law. On 21 January 2021, the Constitutional Court of Moldova declared the law unconstitutional and deprived Russian of the status of the language of interethnic communication. 50% of the population was fluent in Russian in 2006, and 19% used it as the main language with family, friends, or at work. According to the 2014 Moldovan census, Russians accounted for 4.1% of Moldova's population, 9.4% of the population declared Russian as their native language, and 14.5% said they usually spoke Russian.

According to the 2010 census in Russia, Russian language skills were indicated by 138 million people (99.4% of the respondents), while according to the 2002 census – 142.6 million people (99.2% of the respondents).

In Ukraine, Russian is a significant minority language. According to estimates from Demoskop Weekly, in 2004 there were 14,400,000 native speakers of Russian in the country, and 29 million active speakers. 65% of the population was fluent in Russian in 2006, and 38% used it as the main language with family, friends, or at work. On 5 September 2017, Ukraine's Parliament passed a new education law which requires all schools to teach at least partially in Ukrainian, with provisions while allow indigenous languages and languages of national minorities to be used alongside the national language. The law faced criticism from officials in Russia and Hungary. The 2019 Law of Ukraine "On protecting the functioning of the Ukrainian language as the state language" gives priority to the Ukrainian language in more than 30 spheres of public life: in particular in public administration, media, education, science, culture, advertising, services. The law does not regulate private communication. A poll conducted in March 2022 by RATING in the territory controlled by Ukraine found that 83% of the respondents believe that Ukrainian should be the only state language of Ukraine. This opinion dominates in all macro-regions, age and language groups. On the other hand, before the war, almost a quarter of Ukrainians were in favour of granting Russian the status of the state language, while after the beginning of Russia's invasion the support for the idea dropped to just 7%. In peacetime, the idea of raising the status of Russian was traditionally supported by residents of the south and east. But even in these regions, only a third of the respondents were in favour, and after Russia's full-scale invasion, their number dropped by almost half. According to the survey carried out by RATING in August 2023 in the territory controlled by Ukraine and among the refugees, almost 60% of the polled usually speak Ukrainian at home, about 30% – Ukrainian and Russian, only 9% – Russian. Since March 2022, the use of Russian in everyday life has been noticeably decreasing. For 82% of respondents, Ukrainian is their mother tongue, and for 16%, Russian is their mother tongue. IDPs and refugees living abroad are more likely to use both languages for communication or speak Russian. Nevertheless, more than 70% of IDPs and refugees consider Ukrainian to be their native language.

In the 20th century, Russian was a mandatory language taught in the schools of the members of the old Warsaw Pact and in other countries that used to be satellites of the USSR. According to the Eurobarometer 2005 survey, fluency in Russian remains fairly high (20–40%) in some countries, in particular former Warsaw Pact countries.

### Asia

In Armenia, Russian has no official status, but it is recognized as a minority language under the Framework Convention for the Protection of National Minorities. 30% of the population was fluent in Russian in 2006, and 2% used it as the main language with family, friends, or at work.

In Azerbaijan, Russian has no official status, but is a lingua franca of the country. 26% of the population was fluent in Russian in 2006, and 5% used it as the main language with family, friends, or at work.

In China, Russian has no official status, but it is spoken by the small Russian communities in the northeastern Heilongjiang and the northwestern Xinjiang Uyghur Autonomous Region. Russian was also the main foreign language taught in school in China between 1949 and 1964.

In Georgia, Russian has no official status, but it is recognized as a minority language under the Framework Convention for the Protection of National Minorities. Russian is the language of 9% of the population according to the World Factbook. Ethnologue cites Russian as the country's de facto working language.

In Kazakhstan, Russian is not a state language, but according to article 7 of the Constitution of Kazakhstan its usage enjoys equal status to that of the Kazakh language in state and local administration. The 2009 census reported that 10,309,500 people, or 84.8% of the population aged 15 and above, could read and write well in Russian, and understand the spoken language. In October 2023, Kazakhstan drafted a media law aimed at increasing the use of the Kazakh language over Russian, the law stipulates that the share of the state language on television and radio should increase from 50% to 70%, at a rate of 5% per year, starting in 2025.

In Kyrgyzstan, Russian is a co-official language per article 5 of the Constitution of Kyrgyzstan. The 2009 census states that 482,200 people speak Russian as a native language, or 8.99% of the population. Additionally, 1,854,700 residents of Kyrgyzstan aged 15 and above fluently speak Russian as a second language, or 49.6% of the population in the age group.

In Tajikistan, Russian is the language of inter-ethnic communication under the Constitution of Tajikistan and is permitted in official documentation. 28% of the population was fluent in Russian in 2006, and 7% used it as the main language with family, friends or at work. The World Factbook notes that Russian is widely used in government and business.

In Turkmenistan, Russian lost its status as the official lingua franca in 1996. Among 12% of the population who grew up in the Soviet era can speak Russian, other generations of citizens that do not have any knowledge of Russian. Primary and secondary education by Russian is almost non-existent.

In Uzbekistan, Russian is the language of inter-ethnic communication. It has some official roles, being permitted in official documentation and is the lingua franca of the country and the language of the elite. Russian is spoken by 14.2% of the population according to an undated estimate from the World Factbook.

In 2005, Russian was the most widely taught foreign language in Mongolia, and was compulsory in Year 7 onward as a second foreign language in 2006.

Around 1.5 million Israelis spoke Russian as of 2017. The Israeli press and websites regularly publish material in Russian and there are Russian newspapers, television stations, schools, and social media outlets based in the country. There is an Israeli TV channel mainly broadcasting in Russian with Israel Plus. See also Russian language in Israel.

Russian is also spoken as a second language by a small number of people in Afghanistan.

In Vietnam, Russian has been added in the elementary curriculum along with Chinese and Japanese and were named as "first foreign languages" for Vietnamese students to learn, on equal footing with English.

### North America

The Russian language was first introduced in North America when Russian explorers voyaged into Alaska and claimed it for Russia during the 18th century. Although most Russian colonists left after the United States bought the land in 1867, a handful stayed and preserved the Russian language in this region to this day, although only a few elderly speakers of this unique dialect are left. In Nikolaevsk, Alaska, Russian is more spoken than English. Sizable Russian-speaking communities also exist in North America, especially in large urban centers of the US and Canada, such as New York City, Philadelphia, Boston, Los Angeles, Nashville, San Francisco, Seattle, Spokane, Toronto, Calgary, Baltimore, Miami, Portland, Chicago, Denver, and Cleveland. In a number of locations they issue their own newspapers, and live in ethnic enclaves (especially the generation of immigrants who started arriving in the early 1960s). Only about 25% of them are ethnic Russians, however. Before the dissolution of the Soviet Union, the overwhelming majority of Russophones in Brighton Beach, Brooklyn in New York City were Russian-speaking Jews. Afterward, the influx from the countries of the former Soviet Union changed the statistics somewhat, with ethnic Russians and Ukrainians immigrating along with some more Russian Jews and Central Asians. According to the United States Census, in 2007 Russian was the primary language spoken in the homes of over 850,000 individuals living in the United States.

## As an international language

Russian is one of the official languages (or has similar status and interpretation must be provided into Russian) of the following:

- United Nations

- International Atomic Energy Agency

- World Health Organization

- International Civil Aviation Organization

- UNESCO

- World Intellectual Property Organization

- International Telecommunication Union

- World Meteorological Organization

- Food and Agriculture Organization

- International Fund for Agricultural Development

- International Criminal Court

- International Olympic Committee

- Universal Postal Union

- World Bank

- Commonwealth of Independent States

- Organization for Security and Co-operation in Europe

- Shanghai Cooperation Organisation

- Eurasian Economic Community

- Collective Security Treaty Organization

- Antarctic Treaty Secretariat

- International Organization for Standardization

- International Mathematical Olympiad

The Russian language is also one of two official languages aboard the International Space Station – NASA astronauts who serve alongside Russian cosmonauts usually take Russian language courses. This practice goes back to the Apollo–Soyuz mission, which first flew in 1975.

In March 2013, Russian was found to be the second-most used language on websites after English. Russian was the language of 5.9% of all websites, slightly ahead of German and far behind English (54.7%). Russian was used not only on 89.8% of.ru sites, but also on 88.7% of sites with the former Soviet Union domain.su. Websites in former Soviet Union member states also used high levels of Russian: 79.0% in Ukraine, 86.9% in Belarus, 84.0% in Kazakhstan, 79.6% in Uzbekistan, 75.9% in Kyrgyzstan and 81.8% in Tajikistan. However, Russian was the sixth-most used language on the top 1,000 sites, behind English, Chinese, French, German, and Japanese.

## Dialects

Despite leveling after 1900, especially in matters of vocabulary and phonetics, a number of dialects still exist in Russia. Some linguists divide the dialects of Russian into two primary regional groupings, "Northern" and "Southern", with Moscow lying on the zone of transition between the two. Others divide the language into three groupings, Northern, Central (or Middle), and Southern, with Moscow lying in the Central region.

The Northern Russian dialects and those spoken along the Volga River typically pronounce unstressed /o/ clearly, a phenomenon called okanye (оканье). Besides the absence of vowel reduction, some dialects have high or diphthongal /e⁓i̯ɛ/ in place of Proto-Slavic * ě and /o⁓u̯ɔ/ in stressed closed syllables (as in Ukrainian) instead of Standard Russian /e/ and /o/, respectively. Another Northern dialectal morphological feature is a post-posed definite article -to, -ta, -te similar to that existing in Bulgarian and Macedonian.

In the Southern Russian dialects, instances of unstressed /e/ and /a/ following palatalized consonants and preceding a stressed syllable are not reduced to (as occurs in the Moscow dialect), being instead pronounced in such positions (e.g. несл и is pronounced, not) – this is called yakanye (яканье). Consonants include a fricative /ɣ/, a semivowel /w⁓u̯/ and /x⁓xv⁓xw/, whereas the Standard and Northern dialects have the consonants /ɡ/, /v/, and final /l/ and /f/, respectively. The morphology features a palatalized final /tʲ/ in 3rd person forms of verbs (this is unpalatalized in the Standard and Northern dialects).

## Comparison with other Slavic languages

During the Proto-Slavic (Common Slavic) times all Slavs spoke one mutually intelligible language or group of dialects. There is a high degree of mutual intelligibility between Russian, Belarusian and Ukrainian, and a moderate degree of it in all modern Slavic languages, at least at the conversational level.

## Derived languages

- Balachka, a Ukrainian dialect spoken in Krasnodar region, Don, Kuban, and Terek, brought by relocated Cossacks in 1793 and is based on the so-called "southwest Russian" dialect (Ukrainian dialect). During the Russification of the aforementioned regions in the 1920s to 1950s, it was replaced by the Russian language.

- Esperanto has some words of Russian and Slavic origin and some features of its grammar could be derived from Russian.

- Fenya, a criminal argot of ancient origin, with Russian grammar, but with distinct vocabulary

- Lojban, Russian is one of its six source languages, weighed for the number of Russian speakers in 1985.

- Medny Aleut language, an extinct mixed language that was spoken on Bering Island and is characterized by its Aleut nouns and Russian verbs

- Padonkaffsky jargon, a slang language developed by padonki of Runet

- Quelia, a macaronic language with Russian-derived basic structure and part of the lexicon (mainly nouns and verbs) borrowed from German

- Runglish, a Russian-English pidgin. This word is also used by English speakers to describe the way in which Russians attempt to speak English using Russian morphology or syntax.

- Russenorsk, an extinct pidgin language with mostly Russian vocabulary and mostly Norwegian grammar, used for communication between Russians and Norwegian traders in the Pomor trade in Finnmark and the Kola Peninsula

- Surzhyk, a range of mixed (macaronic) sociolects of Ukrainian and Russian languages used in certain regions of Ukraine and adjacent lands.

- Trasianka, a heavily russified variety of Belarusian used by a large portion of the rural population in Belarus

- Taimyr Pidgin Russian, spoken by the Nganasan on the Taimyr Peninsula

## Alphabet

Russian is written using a Cyrillic alphabet. The Russian alphabet consists of 33 letters. The following table gives their forms, along with IPA values for each letter's typical sound:

Older letters of the Russian alphabet include ⟨ ѣ ⟩, which merged to ⟨ е ⟩ (/je/ or /ʲe/); ⟨ і ⟩ and ⟨ ѵ ⟩, which both merged to ⟨ и ⟩ (/i/); ⟨ ѳ ⟩, which merged to ⟨ ф ⟩ (/f/); ⟨ ѫ ⟩, which merged to ⟨ у ⟩ (/u/); ⟨ ѭ ⟩, which merged to ⟨ ю ⟩ (/ju/ or /ʲu/); and ⟨ ѧ ⟩ and ⟨ ѩ ⟩, which later were graphically reshaped into ⟨ я ⟩ and merged phonetically to /ja/ or /ʲa/. While these older letters have been abandoned at one time or another, they may be used in this and related articles. The yers ⟨ ъ ⟩ and ⟨ ь ⟩ originally indicated the pronunciation of ultra-short or reduced /ŭ/, /ĭ/.

### Transliteration

Because of many technical restrictions in computing and also because of the unavailability of Cyrillic keyboards abroad, Russian is often transliterated using the Latin alphabet. For example, мороз ('frost') is transliterated moroz, and мышь ('mouse'), mysh or myš'. Once commonly used by the majority of those living outside Russia, transliteration is being used less frequently by Russian-speaking typists in favor of the extension of Unicode character encoding, which fully incorporates the Russian alphabet. Free programs are available offering this Unicode extension, which allow users to type Russian characters, even on Western 'QWERTY' keyboards.

### Computing

The Russian language was first introduced to computing after the M-1, and MESM models were produced in 1951.

### Orthography

According to the Institute of Russian Language of the Russian Academy of Sciences, an optional acute accent (знак ударения) may, and sometimes should, be used to mark stress. For example, it is used to distinguish between otherwise identical words, especially when context does not make it obvious: замо́к (zamók – "lock") – за́мок (zámok – "castle"), сто́ящий (stóyashchy – "worthwhile") – стоя́щий (stoyáshchy – "standing"), чудно́ (chudnó – "this is odd") – чу́дно (chúdno – "this is marvellous"), молоде́ц (molodéts – "well done!") – мо́лодец (mólodets – "fine young man"), узна́ю (uznáyu – "I shall learn it") – узнаю́ (uznayú – "I recognize it"), отреза́ть (otrezát – "to be cutting") – отре́зать (otrézat – "to have cut"); to indicate the proper pronunciation of uncommon words, especially personal and family names, like афе́ра (aféra, "scandal, affair"), гу́ру (gúru, "guru"), Гарси́я (García), Оле́ша (Olésha), Фе́рми (Fermi), and to show which is the stressed word in a sentence, for example Ты́ съел печенье? (Tý syel pechenye? – "Was it you who ate the cookie?") – Ты съе́л печенье? (Ty syél pechenye? – "Did you eat the cookie?) – Ты съел пече́нье? (Ty syel pechénye? "Was it the cookie you ate?"). Stress marks are mandatory in lexical dictionaries and books for children or Russian learners.

## Phonology

The Russian syllable structure can be quite complex, with both initial and final consonant clusters of up to four consecutive sounds. Using a formula with V standing for the nucleus (vowel) and C for each consonant, the maximal structure can be described as follows:

(C)(C)(C)(C)V(C)(C)(C)(C)

### Consonants

Russian is notable for its distinction based on palatalization of most of its consonants. The phoneme / ts / is generally considered to be always hard; however, loan words such as Цюрих and some other neologisms contain / tsʲ / through the word-building processes (e.g. фрицёнок, шпицята). Palatalization means that the center of the tongue is raised during and after the articulation of the consonant. In the case of /tʲ/ and /dʲ/, the tongue is raised enough to produce slight frication (affricate sounds; cf. Belarusian ць, дзь, or Polish ć, dź). The sounds /t, d, ts, s, z, n, rʲ/ are dental, that is, pronounced with the tip of the tongue against the teeth rather than against the alveolar ridge. According to some linguists, the "plain" consonants are velarized as in Irish, something which is most noticeable when it involves a labial before a hard vowel, such as мы, /mˠɨː/, "we", or бэ, /bˠɛ/, "the letter Б".

### Vowels

Russian has five or six vowels in stressed syllables, /i, u, e, o, a/, and in some analyses /ɨ/, but in most cases these vowels have merged to only two to four vowels when unstressed: /i, u, a/ (or /ɨ, u, a/) after hard consonants and /i, u/ after soft ones. These vowels have several allophones, which are displayed on the diagram to the right.

## Grammar

Russian has preserved an Indo-European synthetic - inflectional structure, although considerable leveling has occurred.Russian grammar encompasses:

- a highly fusional morphology

- a syntax that, for the literary language, is the conscious fusion of three elements: a polished vernacular foundation; a Church Slavonic inheritance; a Western European style.

- a polished vernacular foundation;

- a Church Slavonic inheritance;

- a Western European style.

The spoken language has been influenced by the literary one but continues to preserve characteristic forms. The dialects show various non-standard grammatical features.

In terms of actual grammar, there are three tenses in Russian – past, present, and future – and each verb has two aspects (perfective and imperfective). Russian nouns each have a gender – either feminine, masculine, or neuter, chiefly indicated by spelling at the end of the word. Words change depending on both their gender and function in the sentence. Russian has six cases: Nominative (for the grammatical subject), Accusative (for direct objects), Dative (for indirect objects), Genitive (to indicate possession or relation), Instrumental (to indicate 'with' or 'by means of'), and Prepositional (used after the locative prepositions в "in", на "on", о "about", при "in the presence of"). Verbs of motion in Russian – such as 'go', 'walk', 'run', 'swim', and 'fly' – use the imperfective or perfective form to indicate a single or return trip, and also use a multitude of prefixes to add shades of meaning to the verb. Such verbs also take on different forms to distinguish between concrete and abstract motion.

## Vocabulary

The number of listed words or entries in some of the major dictionaries published during the past two centuries, are as follows:

## History and literary language

No single periodization is universally accepted, but the history of the Russian language is sometimes divided into the following periods:

- Old Russian or Old East Slavic (until the 14th or 15th century)

- Middle Russian (14th or 15th century until the 17th or 18th century)

- Modern Russian (17th century or 18th century to the present)

The history of the Russian language is also divided into Old Russian from the 11th to 17th centuries, followed by Modern Russian.

The political reforms of Peter the Great (Пётр Вели́кий, Pyótr Velíky) were accompanied by a reform of the alphabet, and achieved their goal of secularization and Westernization. Blocks of specialized vocabulary were adopted from the languages of Western Europe. By 1800, a significant portion of the gentry spoke French daily, and German sometimes. Many Russian novels of the 19th century, e.g. Leo Tolstoy 's (Лев Толсто́й) War and Peace, contain entire paragraphs and even pages in French with no translation given, with an assumption that educated readers would not need one.

The modern literary language is usually considered to date from the time of Alexander Pushkin (Алекса́ндр Пу́шкин) in the first third of the 19th century. Pushkin revolutionized Russian literature by rejecting archaic grammar and vocabulary (so-called высо́кий стиль — "high style") in favor of grammar and vocabulary found in the spoken language of the time. Even modern readers of younger age may only experience slight difficulties understanding some words in Pushkin's texts, since relatively few words used by Pushkin have become archaic or changed meaning. In fact, many expressions used by Russian writers of the early 19th century, in particular Pushkin, Mikhail Lermontov (Михаи́л Ле́рмонтов), Nikolai Gogol (Никола́й Го́голь), Aleksander Griboyedov (Алекса́ндр Грибое́дов), became proverbs or sayings which can be frequently found even in modern Russian colloquial speech.

During the Soviet period, the policy toward the languages of the various other ethnic groups fluctuated in practice. Though each of the constituent republics had its own official language, the unifying role and superior status was reserved for Russian, although it was declared the official language only in 1990. Following the break-up of the USSR in 1991, several of the newly independent states have encouraged their native languages, which has partly reversed the privileged status of Russian, though its role as the language of post-Soviet national discourse throughout the region has continued.

The Russian language in the world declined after 1991 due to the collapse of the Soviet Union and decrease in the number of Russians in the world and diminution of the total population in Russia (where Russian is an official language), however this has since been reversed.

According to figures published in 2006 in the journal " Demoskop Weekly " research deputy director of Research Center for Sociological Research of the Ministry of Education and Science (Russia) Arefyev A. L., the Russian language is gradually losing its position in the world in general, and in Russia in particular. In 2012, A. L. Arefyev published a new study "Russian language at the turn of the 20th–21st centuries", in which he confirmed his conclusion about the trend of weakening of the Russian language after the Soviet Union's collapse in various regions of the world (findings published in 2013 in the journal " Demoskop Weekly "). In the countries of the former Soviet Union the Russian language was being replaced or used in conjunction with local languages. Currently, the number of speakers of Russian in the world depends on the number of Russians in the world and total population in Russia.

## Sample text

Article 1 of the Universal Declaration of Human Rights in Russian:

Все люди рождаются свободными и равными в своем достоинстве и правах. Они наделены разумом и совестью и должны поступать в отношении друг друга в духе братства.

The romanization of the text into Latin alphabet:

Vse lyudi rozhdayutsya svobodnymi i ravnymi v svoyem dostoinstve i pravakh. Oni nadeleny razumom i sovest'yu i dolzhny postupat' v otnoshenii drug druga v dukhe bratstva.

Article 1 of the Universal Declaration of Human Rights in English:

All human beings are born free and equal in dignity and rights. They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.


Multiple sub-Nyquist sampling encoding

# Multiple sub-Nyquist sampling encoding

## Abstract

MUSE (Multiple sub-Nyquist Sampling Encoding), commercially known as Hi-Vision (a contraction of HI gh-definition tele VISION) was a Japanese analog high-definition television system, with design efforts going back to 1979.

It used dot-interlacing and digital video compression to deliver 1125 line, 60 field-per-second (1125i60) signals to the home. The system was standardized as ITU -R recommendation BO.786 and specified by SMPTE 260M, using a colorimetry matrix specified by SMPTE 240M. As with other analog systems, not all lines carry visible information. On MUSE there are 1035 active interlaced lines, therefore this system is sometimes also mentioned as 1035i. It employed 2-dimensional filtering, dot-interlacing, motion-vector compensation and line-sequential color encoding with time compression to "fold" an original 30 MHz bandwidth Hi-Vision source signal into just 8.1 MHz.

Japan began broadcasting wideband analog HDTV signals in December 1988, initially with an aspect ratio of 2:1. The Sony HDVS high-definition video system was used to create content for the MUSE system, but didn't record MUSE signals. It recorded Hi-Vision signals which are uncompressed.By the time of its commercial launch in 1991, digital HDTV was already under development in the United States. Hi-Vision was mainly broadcast by NHK through their BShi satellite TV channel, although other channels such as WOWOW, TV Asahi, Fuji Television, TBS Television, Nippon Television, and TV Tokyo also broadcast in MUSE.

On May 20, 1994, Panasonic released the first MUSE LaserDisc player. There were also a number of players available from other brands like Pioneer and Sony.

Hi-Vision continued broadcasting in analog until 2007.

## History

MUSE was developed by NHK Science & Technology Research Laboratories in the 1980s as a compression system for Hi-Vision HDTV signals.

- Japanese broadcast engineers immediately rejected conventional vestigial sideband broadcasting.

- It was decided early on that MUSE would be a satellite broadcast format as Japan economically supports satellite broadcasting. MUSE was transmitted at a frequency of 21 GHz or 12 GHz.

- Japanese broadcast engineers had been studying the various HDTV broadcast types for some time. It was initially thought that SHF, EHF or optic fiber would have to be used to transmit HDTV due to the high bandwidth of the signal, and HLO-PAL would be used for terrestrial broadcast. HLO-PAL is a conventionally constructed composite signal (based on Y {\displaystyle Y} for luminance and C {\displaystyle C} for chroma like NTSC and PAL) and uses a phase alternating by line with half-line offset carrier encoding of the wideband/narrowband chroma components. Only the very lowest part of the wideband chroma component overlapped the high-frequency chroma. The narrowband chroma was completely separated from luminance. PAF, or phase alternating by field (like the first NTSC color system trial) was also experimented with, and it gave much better decoding results, but NHK abandoned all composite encoding systems. Because of the use of satellite transmission, Frequency modulation (FM) should be used with power-limitation problem. FM incurs triangular noise, so if a sub-carrierred composite signal is used with FM, demodulated chroma signal has more noise than luminance. Because of this, they looked at other options, and decided to use Y / C {\displaystyle Y/C} component emission for satellite. At one point, it seemed that FCFE (Frame Conversion Fineness Enhanced), I/P conversion compression system, would be chosen, but MUSE was ultimately picked.

- Separate transmission of Y {\displaystyle Y} and C {\displaystyle C} components was explored. The MUSE format which is transmitted today, uses separated component signalling. The improvement in picture quality was so great, that the original test systems were recalled.

- One more power saving tweak was made: lack of visual response to low frequency noise allows significant reduction in transponder power if the higher video frequencies are emphasised prior to modulation at the transmitter and de-emphasized at the receiver.

## Technical specifications

MUSE's "1125 lines" are an analog measurement, which includes non-video scan lines taking place while a CRT 's electron beam returns to the top of the screen to begin scanning the next field. Only 1035 lines have picture information. Digital signals count only the lines (rows of pixels) that have actual detail, so NTSC's 525 lines become 486i (rounded to 480 to be MPEG compatible), PAL's 625 lines become 576i, and MUSE would be 1035i. To convert the bandwidth of Hi-Vision MUSE into "conventional" lines-of-horizontal resolution (as is used in the NTSC world), multiply 29.9 lines per MHz of bandwidth. (NTSC and PAL/SECAM are 79.9 lines per MHz) - this calculation of 29.9 lines works for all current HD systems including Blu-ray and HD-DVD. So, for MUSE, during a still picture, the lines of resolution would be: 598-lines of luminance resolution per-picture-height. The chroma resolution is: 209-lines. The horizontal luminance measurement approximately matches the vertical resolution of a 1080 interlaced image when the Kell factor and interlace factor are taken into account. 1125 lines was selected as a compromise between the resolution in lines of NTSC and PAL and then doubling this number.

MUSE employs time-compression integration (TCI) which is another term for time-division multiplexing, which is used to carry luminance, chrominance, PCM audio and sync signals on one carrier signal/in one carrier frequency. However, TCI achieves multiplexing by compression of the contents in the time dimension, in other words transmitting frames of video that are divided into regions with chrominance compressed into the left of the frame and luminance compressed into the right of the frame, which must then be expanded and layered to create a visible image. This makes it different from NTSC which carries luminance, audio and chrominance simultaneously in several carrier frequencies. Hi-Vision signals are component video signals with 3 channels: they were RGB initially, and later YP P.

Key features of the MUSE system:

- Scanlines (total/active): 1,125/1,035

- Pixels per line (fully interpolated): 1122 (still image)/748 (moving)

- Reference clock periods: 1920 per active line

- Interlaced ratio: 2:1

- Aspect ratio 16:9

- Refresh rate: 59.94 or 60 frames per second

- Sampling frequency for broadcast: 16.2 MHz

- Vector motion compensation: horizontal ± 16 samples (32.4 MHz clock) / frame, a vertical line ± 3 / Field

- Audio: "DANCE" discrete 2- or 4-channel digital audio system: 48 kHz/16 bit (2 channel stereo: 2 front channels)/32 kHz/12 bit (4 channel surround: 3 front channels + 1 back channel)

- DPCM Audio compression format: DPCM quasi-instantaneous companding

- Required bandwidth: 27 MHz

### Colorimetry

The MUSE luminance signal Y {\displaystyle Y} encodes Y M {\displaystyle YM}, specified as the following mix of the original RGB color channels:

The chrominance C {\displaystyle C} signal encodes B − Y M {\displaystyle B-YM} and R − Y M {\displaystyle R-YM} difference signals. By using these three signals (Y M {\displaystyle YM}, B − Y M {\displaystyle B-YM} and R − Y M {\displaystyle R-YM}), a MUSE receiver can retrieve the original RGB color components using the following matrix:

The system used a colorimetry matrix specified by SMPTE 240M (with coefficients corresponding to the SMPTE RP 145 primaries, also known as SMPTE-C, in use at the time the standard was created). The chromaticity of the primary colors and white point are:

The luma (E Y {\displaystyle EY}) function is specified as:

The blue color difference (E P B {\displaystyle EPB}) is amplitude-scaled (E B − E Y {\displaystyle EB-EY}), according to:

The red color difference (E P R {\displaystyle EPR}) is amplitude-scaled (E R − E Y {\displaystyle ER-EY}), according to:

### Signal and Transmission

MUSE is a 1125 line system (1035 visible), and is not pulse and sync compatible with the digital 1080 line system used by modern HDTV. Originally, it was a 1125 line, interlaced, 60 Hz, system with a 5:3 (1.66:1) aspect ratio and an optimal viewing distance of roughly 3.3H. In 1989 this was changed to a 16:9 aspect ratio.

For terrestrial MUSE transmission a bandwidth limited FM system was devised. A satellite transmission system uses uncompressed FM.

The pre-compression bandwidth for Y {\displaystyle Y} is 20 MHz, and the pre-compression bandwidth for chrominance is a 7.425 MHz carrier.

The Japanese initially explored the idea of frequency modulation of a conventionally constructed composite signal. This would create a signal similar in structure to the Y / C {\displaystyle Y/C} composite video NTSC signal - with the Y {\displaystyle Y} (luminance) at the lower frequencies and the C {\displaystyle C} (chrominance) above. Approximately 3 kW of power would be required, in order to get 40 dB of signal to noise ratio for a composite FM signal in the 22 GHz band. This was incompatible with satellite broadcast techniques and bandwidth.

To overcome this limitation, it was decided to use a separate transmission of Y {\displaystyle Y} and C {\displaystyle C}. This reduces the effective frequency range and lowers the required power. Approximately 570 W (360 for Y {\displaystyle Y} and 210 for C {\displaystyle C}) would be needed in order to get a 40 dB of signal to noise ratio for a separate Y / C {\displaystyle Y/C} FM signal in the 22 GHz satellite band. This was feasible.

There is one more power saving that appears from the character of the human eye. The lack of visual response to low frequency noise allows significant reduction in transponder power if the higher video frequencies are emphasized prior to modulation at the transmitter and then de-emphasized at the receiver. This method was adopted, with crossover frequencies for the emphasis/de-emphasis at 5.2 MHz for Y {\displaystyle Y} and 1.6 MHz for C {\displaystyle C}. With this in place, the power requirements drop to 260 W of power (190 for Y {\displaystyle Y} and 69 for C {\displaystyle C}).

## Sampling systems and ratios

The subsampling in a video system is usually expressed as a three part ratio. The three terms of the ratio are: the number of brightness (luma) Y {\displaystyle Y} samples, followed by the number of samples of the two color (chroma) components C b {\displaystyle Cb} and C r {\displaystyle Cr}, for each complete sample area. Traditionally the value for brightness is always 4, with the rest of the values scaled accordingly.

A sampling of 4:4:4 indicates that all three components are fully sampled. A sampling of 4:2:0, for example, indicated that the two chroma components are sampled at half the horizontal sample rate of luma - the horizontal chroma resolution is halved. This reduces the bandwidth of an uncompressed video signal by one-third.

MUSE implements a similar system as a means of reducing bandwidth, but instead of static sampling, the actual ratio varies according to the amount of motion on the screen. In practice, MUSE sampling will vary from approximately 4:2:1 to 4:0.5:0.25, depending on the amount of movement. Thus the red-green chroma component C r {\displaystyle Cr} has between one-half and one-eighth the sampling resolution of the luma component Y {\displaystyle Y}, and the blue-yellow chroma C b {\displaystyle Cb} has half the resolution of red-green.

## Audio subsystem

MUSE had a discrete 2- or 4-channel digital audio system called " DANCE ", which stood for Digital Audio Near-instantaneous Compression and Expansion.

It used differential audio transmission (differential pulse-code modulation) that was not psychoacoustics-based like MPEG-1 Layer II. It used a fixed transmission rate of 1350 kbp/s. Like the PAL NICAM stereo system, it used near-instantaneous companding (as opposed to Syllabic-companding like the dbx system uses) and non-linear 13-bit digital encoding at a 32 kHz sample rate.

It could also operate in a 48 kHz 16-bit mode. The DANCE system was well documented in numerous NHK technical papers and in a NHK-published book issued in the USA called Hi-Vision Technology.

The DANCE audio codec was superseded by Dolby AC-3 (a.k.a. Dolby Digital), DTS Coherent Acoustics (a.k.a. DTS Zeta 6x20 or ARTEC), MPEG-1 Layer III (a.k.a. MP3), MPEG-2 Layer I, MPEG-4 AAC and many other audio coders. The methods of this codec are described in the IEEE paper:

## Real world performance issues

MUSE had a four-field dot-interlacing cycle, meaning it took four fields to complete a single MUSE frame. Thus, only stationary images were transmitted at full resolution. However, as MUSE lowers the horizontal and vertical resolution of material that varies greatly from frame to frame, moving images were blurred. Because MUSE used motion-compensation, whole camera pans maintained full resolution, but individual moving elements could be reduced to only a quarter of the full frame resolution. Because the mix between motion and non-motion was encoded on a pixel-by-pixel basis, it wasn't as visible as most would think. Later, NHK came up with backwards compatible methods of MUSE encoding/decoding that greatly increased resolution in moving areas of the image as well as increasing the chroma resolution during motion. This so-called MUSE-III system was used for broadcasts starting in 1995 and a very few of the last Hi-Vision MUSE LaserDiscs used it (A River Runs Through It is one Hi-Vision LD that used it). During early demonstrations of the MUSE system, complaints were common about the decoder's large size, which led to the creation of a miniaturized decoder.

Shadows and multipath still plague this analog frequency modulated transmission mode.

Japan has since switched to a digital HDTV system based on ISDB, but the original MUSE-based BS Satellite channel 9 (NHK BS Hi-vision) was broadcast until September 30, 2007.

## Cultural and geopolitical impacts

- (1940s): The NTSC standard (as a 525 line monochrome system) was imposed by the US occupation forces.

- (1950s-1960s): Unlike Canada (that could have switched to PAL), Japan was stuck with the US TV transmission standard regardless of circumstances.

- (1960s-1970s): By the late 1960s many parts of the modern Japanese electronics industry had gotten their start by fixing the transmission and storage problems inherent with NTSC's design.

- (1970s-1980s): By the 1980s there was spare engineering talent available in Japan that could design a better television system.

MUSE, as the US public came to know it, was initially covered in the magazine Popular Science in the mid-1980s. The US television networks did not provide much coverage of MUSE until the late 1980s, as there were few public demonstrations of the system outside Japan.

Because Japan had its own domestic frequency allocation tables (that were more open to the deployment of MUSE) it became possible for this television system to be transmitted by Ku Band satellite technology by the end of the 1980s.

The US FCC in the late 1980s began to issue directives that would allow MUSE to be tested in the US, providing it could be fit into a 6 MHz System-M channel.

The Europeans (in the form of the European Broadcasting Union (EBU)) were impressed with MUSE, but could never adopt it because it is a 60 Hz TV system, not a 50 Hz system that is standard in Europe and the rest of the world (outside the Americas and Japan).

The EBU development and deployment of B-MAC, D-MAC and much later on HD-MAC were made possible by Hi-Vision's technical success. In many ways MAC transmission systems are better than MUSE because of the total separation of colour from brightness in the time domain within the MAC signal structure.

Like Hi-Vision, HD-MAC could not be transmitted in 8 MHz channels without substantial modification – and a severe loss of quality and frame rate. A 6 MHz version Hi-Vision was experimented with in the US, but it too had severe quality problems so the FCC never fully sanctioned its use as a domestic terrestrial television transmission standard.

The US ATSC working group that had led to the creation of NTSC in the 1950s was reactivated in the early 1990s because of Hi-Vision's success. Many aspects of the DVB standard are based on work done by the ATSC working group, however most of the impact is in support for 60 Hz (as well as 24 Hz for film transmission) and uniform sampling rates and interoperable screen sizes.

## Device support for Hi-Vision

### Hi-Vision LaserDiscs

On May 20, 1994, Panasonic released the first MUSE LaserDisc player. There were a number of MUSE LaserDisc players available in Japan: Pioneer HLD-XØ, HLD-X9, HLD-1000, HLD-V500, HLD-V700; Sony HIL-1000, HIL-C1 and HIL-C2EX; the last two of which have OEM versions made by Panasonic, LX-HD10 and LX-HD20. Players also supported standard NTSC LaserDiscs. Hi-Vision LaserDiscs are extremely rare and expensive.

The HDL-5800 Video Disc Recorder recorded both high definition still images and continuous video onto an optical disc and was part of the early analog wideband Sony HDVS high-definition video system which supported the MUSE system. Capable of recording HD still images and video onto either the WHD-3AL0 or the WHD-33A0 optical disc; WHD-3Al0 for CLV mode (up to 10 minute video or 18,000 still frames per side); WHD-33A0 for CAV mode (up to 3 minute video or 5400 still frames per side). These video discs were used for short video content such as advertisements and product demonstrations.

The HDL-2000 was a full band high definition video disc player.

### Reel to reel VTRs

For recording Hi-Vision signals, Three reel to reel analog VTRs were released, among them are the Sony HDV-1000, the NEC TT 8-1000 and the Toshiba TVR-1000. These analog VTRs had a head drum angular speed of 3600 RPM and are similar to Type C VTRs. They have a bandwidth of 30 Mhz for luma and 7 Mhz for both chroma channels each, with a signal to noise ratio of 41 dB. They accept luma and chroma signals with bandwidths of up to 30 Mhz for both. Signals are recorded onto the tape using FM modulation. Linear tape speed is 483.1 mm/s and writing speed at the heads is 25.9 m/s. The head drum is 134.5 mm wide and has 4 video record heads, 4 video playback heads and 1 erasing head. It could record for 45 minutes on 10.5 inch reels. The video heads are made of Mn-Zn ferrite material, those used for recording have a gap of 0.7 microns and a width of 80 microns and those for playback have a gap of 0.35 microns and a width of 70 microns. It records audio on 3 linear tracks, and control signals on a linear track. Unlike conventional type C videotape recorders, Vertical Blanking Intervals are not recorded on the tape. Helical tracks have groups of 4 signals length-wise with red chrominance, blue chrominance, and two green chrominance signals with luminance information. Two tracks for green chrominance plus luminance are used to increase the bandwidth of these signals that can be recorded on the tape.

In 1987, technical standards for digital recording of Hi-Vision signals were released by NHK, and Sony and Hitachi developed the HDD-1000 and the HV-1200 digital reel to reel VTRs respectively. Audio is recorded digitally similarly to a DASH (Digital Audio Stationary Head) digital audio recorder, but several changes were made to synchronize the audio to the video. These digital VTRs can record 8 channels of digital audio on linear tracks (horizontally along the entire length of the tape). According to the standards, these VTRs operate with a head drum speed of 7200 RPM, have a bit rate of 148.5 Mbit/s per video head, a linear tape speed of 805.2 mm/s and a writing speed at the heads of 51.5 m/s, are similar to Type C VTRs, have a head drum 135mm wide, 8 playback, 8 recording and 2 erase heads, with 37 micron wide helical tracks. Bandwidth is 30 Mhz for luma (Y) and 15 Mhz for chroma (P, P). Audio is recorded with a sampling rate of 48 kHz stored at 16 bits per sample in linear tape tracks, sampling rate for luma is 74.25 Mhz and 37.125 Mhz for chroma stored at 8 bits per sample. Signal to noise ratio is 56 dB for chroma and luma. Video fields are divided into 16 helical tracks on the tape. Total video bandwidth is 1.188 gigabits/s. Cue signals are recorded into 3 linear tape tracks. Video is recorded in groups of 4 tracks length-wise within each helical track, to allow for parallelization: high total data rates with relatively low data rates per head, and reduce the linear tape speed. Digital video signals are recorded line by line (1 row of pixels in every frame of video or 1 line of video at a time) with ECC (Error Correcting Code) at the end of each line and in between a number of vertical lines. Reed-Solomon code is used for ECC and each line also has an ID number for trick play such as slow motion and picture search/shuttle.

### Displays

Hi-Vision requires a display capable of handling 30 Mhz of video bandwidth simultaneously for each of the component video channels: Y, P and P. It was displayed on direct view color CRTs and CRT projectors, and plasma displays and Talaria projectors were explored to determine their ability to display Hi-Vision images.

### Cameras

Cameras based on Saticon tubes, Plumbicon tubes, Harpicon tubes and CCD image sensors were used to capture footage using the Hi-Vision format. A prototype based on Vidicon tubes was also created.

### MUSE decoders

A MUSE decoder is required for receiving MUSE broadcasts from satellites, and for viewing content in the MUSE format. The decoder converts MUSE format signals into Hi-Vision component video signals that can then be shown in a display.

### Video cassettes

W-VHS allowed home recording of Hi-Vision programmes.

For recording Hi-Vision video, NHK and 10 Japanese companies ("NEC, Matsushita Electric Industrial, Toshiba, Sharp, Sony, Hitachi, Sanyo Electric, JVC, Mitsubishi Electric, Canon") in 1989 released UniHi, a professional videocassette format. Recorders for the format were manufactured by Panasonic, Sony, NEC, and Toshiba. These machines were less expensive than their Type C counterparts. Both studio and portable versions were made. The head drum spins at 5400 RPM and uses tape that is 12.65 mm wide. It has a luminance (Y) bandwidth of 20 MHz and a chrominance (P, P) bandwidth of 7 MHz. The head drum is 76mm wide. It uses two video heads with azimuth recording and records each frame of video into 12 helical tracks; only 6 tracks are necessary for each video field if recording interlaced video. Audio is recorded digitally as a PCM signal, as a section on the helical tracks. Writing speed at the heads is 21.4 m/s. The tape also has 3 linear tracks, one for audio, control and time code each. Signal to noise ratio for luminance is 41 dB and for chrominance it is 47 dB. The tape is wrapped 180° around the head drum. Development began in 1987. It uses metal particle tape. It could record video for 1 hour (63 minutes). Linear tape speed is 120 mm/s. The cassette measures 205mm (width) x 121mm (depth) x 25mm (height). Signals are recorded using time-compression integration, in groups of two signals length-wise on each helical track. Grouping is used to increase the bandwidth that can be recorded on the tape. The cassette is intented to be air-tight with two flaps in the cassette's opening to protect the tape.

This videocassette format was developed in order to reduce the size of HD recording equipment. The Sony version of the UniHi VTR, the HDV-10, had a price of over 90,000 US dollars.


Protective distribution system

# Protective distribution system

## Abstract

A protective distribution system (PDS), also called protected distribution system, is a US government term for wireline or fiber-optic telecommunication system that includes terminals and adequate acoustical, electrical, electromagnetic, and physical safeguards to permit its use for the unencrypted transmission of classified information. At one time these systems were called " approved circuits ".

A complete protected distribution system includes the subscriber and terminal equipment and the interconnecting lines.

## Description

The purpose of a PDS is to deter, detect and/or make difficult physical access to the communication lines carrying national security information.A specification called the National Security Telecommunications and Information Systems Security Instruction (NSTISSI) 7003 was issued in December 1996 by the Committee on National Security Systems. Approval authority, standards, and guidance for the design, installation, and maintenance for PDS are provided by NSTISSI 7003 to U.S. government departments and agencies and their contractors and vendors. This instruction describes the requirements for all PDS installations within the U.S. and for low and medium threat locations outside the U.S.PDS is commonly used to protect SIPRNet and JWICS networks.The document superseded one numbered NASCI 4009 on Protected Distribution Systems, dated December 30, 1981, and part of a document called NACSEM 5203, that covered guidelines for facility design, using the designations "red" and "black".

There are two types of PDS: hardened distribution systems and simple distribution systems.

## Hardened distribution

Hardened distribution PDSs provide significant physical protection and can be implemented in three forms: hardened carrier PDSs, alarmed carrier PDSs and continuously viewed carrier PDSs.

### Hardened carrier

In a hardened carrier PDS, the data cables are installed in a carrier constructed of electrical metallic tubing (EMT), ferrous conduit or pipe, or rigid sheet steel ducting. All of the connections in a Hardened Carrier System are permanently sealed completely around all surfaces with welds, epoxy or other such sealants. If the hardened carrier is buried under ground, to secure cables running between buildings for example, the carrier containing the cables is encased in concrete.

With a hardened carrier system, detection is accomplished via human inspections that are required to be performed periodically. Therefore, hardened carriers are installed below ceilings or above flooring so they can be visually inspected to ensure that no intrusions have occurred. These periodic visual inspections (PVIs) occur at a frequency dependent upon the level of threat to the environment, the security classification of the data, and the access control to the area.

### Alarmed carrier

As an alternative to conducting human visual inspections, an alarmed carrier PDS may be constructed to automate the inspection process through electronic monitoring with an alarm system. In an Alarmed Carrier PDS, the carrier system is “alarmed” with specialized optical fibers deployed within the conduit for the purpose of sensing acoustic vibrations that usually occur when an intrusion is being attempted on the conduit in order to gain access to the cables.

Alarmed carrier PDS offers several advantages over hardened carrier PDS:

- Provides continuous monitoring 24/7/365

- Eliminates the requirement for periodic visual inspections

- Allows the carrier to be hidden above the ceiling or below the floor, since periodic visual inspections are not required

- Eliminates the need for the welding and epoxying of the connections

- Eliminates the requirement for concrete encasement outdoors

- Eliminates the need to lock down manhole covers

- Enables rapid redeployment for evolving network arrangements

Legacy alarmed carrier systems monitor the carrier containing the cables being protected. More advanced systems monitor the fibers within, or intrinsic to, the cables being protected to turn those cables into sensors, which detect intrusion attempts.

Depending on the government organization, utilizing an alarmed carrier PDS in conjunction with interlocking armored cable may, in some cases, allow for the elimination of the carrier systems altogether. In these instances, the cables being protected can be installed in existing conveyance (wire basket, ladder rack) or suspended cabling (on D-rings, J-Hooks, etc.).

### Continuously viewed carrier

A Continuously Viewed Carrier PDS is one that is under continuous observation, 24 hours per day (including when operational). Such circuits may be grouped together, but should be separated from all non-continuously viewed circuits ensuring an open field of view. Standing orders should include the requirement to investigate any attempt to disturb the PDS. Appropriate security personnel should investigate the area of attempted penetration within 15 minutes of discovery. This type of hardened carrier is not used for Top Secret or special category information for non-U.S. UAA. UAA is an Uncontrolled Access Area (UAA). Like definitions include Controlled Access Area (CAA) and Restricted Access Area (RAA). A Secure Room (SR) offers the highest degree of protection.

Therefore, from the least protected (least secure) to the most protected is as follows:

UAARAACAASR

## Simple distribution

Simple distribution PDSs are afforded a reduced level of physical security protection as compared to a hardened distribution PDS. They use a simple carrier system and the following means are acceptable under NSTISSI 7003:

- The data cables should be installed in a carrier

- The carrier can be constructed of any material (e.g., wood, PVT, EMT, ferrous conduit)

- The joints and access points should be secured and be controlled by personnel cleared to the highest level of data handled by the PDS

- The carrier is to be inspected in accordance with the requirements of NSTISSI 7003