EnergyIn physics, energy () is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J).
Graph databaseA graph database (GDB) is a database that uses graph structures for semantic queries with nodes, edges, and properties to represent and store data. A key concept of the system is the graph (or edge or relationship). The graph relates the data items in the store to a collection of nodes and edges, the edges representing the relationships between the nodes. The relationships allow data in the store to be linked together directly and, in many cases, retrieved with one operation.
Vizing's theoremIn graph theory, Vizing's theorem states that every simple undirected graph may be edge colored using a number of colors that is at most one larger than the maximum degree Δ of the graph. At least Δ colors are always necessary, so the undirected graphs may be partitioned into two classes: "class one" graphs for which Δ colors suffice, and "class two" graphs for which Δ + 1 colors are necessary. A more general version of Vizing's theorem states that every undirected multigraph without loops can be colored with at most Δ+μ colors, where μ is the multiplicity of the multigraph.
Material flow analysisMaterial flow analysis (MFA), also referred to as substance flow analysis (SFA), is an analytical method to quantify flows and stocks of materials or substances in a well-defined system. MFA is an important tool to study the bio-physical aspects of human activity on different spatial and temporal scales. It is considered a core method of industrial ecology or anthropogenic, urban, social and industrial metabolism. MFA is used to study material, substance, or product flows across different industrial sectors or within ecosystems.
Energy accountingEnergy accounting is a system used to measure, analyze and report the energy consumption of different activities on a regular basis. This is done to improve energy efficiency, and to monitor the environment impact of energy consumption. Energy accounting is a system used in energy management systems to measure and analyze energy consumption to improve energy efficiency within an organization. Organisations such as Intel corporation use these systems to track energy usage. Various energy transformations are possible.
Local purchasingLocal purchasing is a preference to buy locally produced goods and services rather than those produced farther away. It is very often abbreviated as a positive goal, "buy local" or "buy locally', that parallels the phrase "think globally, act locally", common in green politics. On the national level, the equivalent of local purchasing is import substitution, the deliberate industrial policy or agricultural policy of replacing goods or services produced on the far side of a national border with those produced on the near side, i.