Suchergebnisse

1 Introduction -- Structure of the book -- Understanding fields -- 2 Electrical conduction and currents -- Current and charge -- Conduction equations -- Current as an example of flux -- Models of electrical conduction -- Resistive circuit components -- 3 Potential and the electric field -- Potential (voltage) in a circuit -- Electric field -- Conduction and charge mobility -- Potential and field in space -- Acceleration of charged particles in an electric field -- 4 Charge and electric flux -- Capacitance -- Electric flux and permittivity -- Calculations in electrostatics -- 5 Electric fields in materials -- Polarization and dielectrics -- Electrostatic force and energy -- Capacitor design -- Further applications -- 6 Magnetic flux and circuits -- Electromagnetic induction -- Magnetomotive force, flux and reluctance -- Magnetic circuits -- 7 Magnetic vectors -- Vector B and flux -- Directional rules and Lenz' law -- Magnetic scalar potential and vector H -- Predicting magnetic fields -- 8 Inductance and magnetic materials -- Self and mutual inductance -- Air-cored inductors -- Calculations in magnetism -- Magnetization -- Electromagnetic machinery -- Some applications -- 9 Magnetic energy and force -- Magnetic energy -- Reluctance force -- Permanent magnets -- Force from the motor effect -- 10 Electromagnetism and charged particles -- The Lorentz force -- The Hall effect -- Applications of the Hall effect -- Electron streams -- Acceleration of electrons -- Deflection and focusing of electron streams -- Some applications of electron streams -- 11 The electromagnetic field -- The time needed to establish a current -- Electromagnetic waves -- Electromagnetism and relativity -- Final comments -- The fundamental rules of electromagnetism -- Appendix: A brief note on integration -- Answers to problems.

Sectorization means dividing a set of basic units into sectors or parts, a procedure that occurs in several contexts, such as political, health and school districting, social networks and sales territory or airspace assignment, to achieve some goal or to facilitate an activity. This presentation will focus on three main issues: Measures, a new approach to sectorization problems and an application in waste collection. When designing or comparing sectors different characteristics are usually taken into account. Some are commonly used, and they are related to the concepts of contiguity, equilibrium and compactness. These fundamental characteristics will be addressed, by defining new generic measures and by proposing a new measure, desirability, connected with the idea of preference. A new approach to sectorization inspired in Coulomb's Law, which establishes a relation of force between electrically charged points, will be proposed. A charged point represents a small region with specific characteristics/values creating relations of attraction/repulsion with the others (two by two), proportional to the charges and inversely proportional to their distance. Finally, a real case about sectorization and vehicle routing in solid waste collection will be mentioned.