You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Reduction of Power Consumption in FPGAs - An Overview 
Chapter Title:  b) Packing 
1. Abstract of Cited Paper (BIB001):  Top-down partitioning has focused on minimum cut or ratio cut objectives, while bottom-up clustering has focused on density-based objectives. In seeking a more unified perspective, we propose a new sum of densities measure for multi-way circuit decomposition, where the density of a subhypergraph is the ratio of the number of edges to the number of nodes in the subhypergraph. Finding a k-way partition that maximizes the sum of k subhypergraph densities is NP-hard, but an efficient flow-based method can find the optimal (maximum-density) subhypergraph in a given hypergraph. Based on this method, we develop a heuristic which in practice has less than 10% error from an optimal sum of densities decomposition. Other results suggest that density-based heuristics can capture cut-based objectives, whereas the converse would seem difficult. >

Literature Review:
The packing phase converts the netlist of LUTs and flip-flops into a netlist of logic locks. The input netlist is converted into clusters of logic blocks that can be mapped into the physical logic blocks of the FPGA. Most packing algorithms minimize the number of resulting logic blocks, the number of connections between them, and/or the delay along the critical path. The packing algorithm has to consider the physical limitations of the actual logic blocks of the FPGA in terms of the maximum number of LUTs in a logic block and the number of distinct input signals and clocks a logic block has. Packing algorithms can be categorized as either bottom-up [14, 18, 19, and 20] or top-down BIB001 BIB002 . Bottom-up packing algorithms build each cluster individually around a seed LUT until the cluster is full. However, top-down packing approaches partition the LUTs into clusters by successive circuit subdivision. Bottom-up algorithms are much faster and simpler than top-down approaches because they only consider local connections. However, this comes at the expense of solution quality.