44 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Linear Programming"  
Results: 1 - 24 next
open access

Experiment in multiple-criteria energy policy analysis. [Using HOPE (holistic preference evaluation)]

Description: An international panel of energy analysts participated in an experiment to use HOPE (holistic preference evaluation): an interactive parametric linear-programming method for multiple-criteria optimization. The criteria of cost, environmental effect, crude oil, and nuclear fuel were considered according to BESOM: an energy model for the US in the year 2000.
Date: July 1, 1980
Creator: Ho, J K
Partner: UNT Libraries Government Documents Department
open access

Energy optimization in DOD facilities

Description: A static linear programming formulation (management tool) of energy optimization problems on military bases has been developed to assist each of the military services in their planning activities and budgetary allocation decisions. Several objective functions have been defined, resulting in two types of model capabilities: minimization of capital costs (investments) subject to a number of energy and dollar constraints and the maximization of energy savings subject to capital and operating fund … more
Date: January 1, 1981
Creator: Roach, F.; Kirschner, C. & Salmon, R.
Partner: UNT Libraries Government Documents Department
open access

Linear-programming approach to county-level energy-scenario disaggregation

Description: Many recent national and regional Energy Planning Studies utilize the scenario approach as a framework for R and D Assessment or policy analysis, with information detail at best to the census or Reliability Council Region level. Unfortunately, such scenarios are of limited utility to State Agencies, or to those interested in environmental-impact or resource-constraint questions. This paper describes an LP disaggregation procedure to translate regional energy scenarios to county-level detail, wi… more
Date: January 1, 1977
Creator: Meier, P.M.
Partner: UNT Libraries Government Documents Department
open access

Linear-programming approach to electricity demand-curtailment planning

Description: Curtailment planning at a generally rudimentary level has been undertaken by the governments of some twenty states. Many utilities have demand-curtailment plans, however, these are often incorporated in plans for meeting capacity shortages. In at least five states, there are apparently no curtailment plans either at the state-government level or at the utility level. Moreover, none of the existing electricity demand curtailment plans examined included an explicit statement of the planners'… more
Date: May 1, 1980
Creator: Allentuck, J; Carroll, O & Schnader, M
Partner: UNT Libraries Government Documents Department
open access

LIFT: a nested decomposition algorithm for solving lower block triangular linear programs. Report AMD-859. [In PL/I for IBM 370]

Description: Nested decomposition of linear programs is the result of a multilevel, hierarchical application of the Dantzig-Wolfe decomposition principle. The general structure is called lower block-triangular, and permits direct accounting of long-term effects of investment, service life, etc. LIFT, an algorithm for solving lower block triangular linear programs, is based on state-of-the-art modular LP software. The algorithmic and software aspects of LIFT are outlined, and computational results are presen… more
Date: June 1, 1980
Creator: Ament, D; Ho, J; Loute, E & Remmelswaal, M
Partner: UNT Libraries Government Documents Department
open access

Seismic monitoring of EGS tests at the Coso Geothermal area, California, using accurate MEQ locations and full moment tensors

Description: We studied high-resolution relative locations and full moment tensors of microearthquakes (MEQs) occurring before, during and following Enhanced Geothermal Systems (EGS) experiments in two wells at the Coso geothermal area, California. The objective was to map new fractures, determine the mode and sense of failure, and characterize the stress cycle associated with injection. New software developed for this work combines waveform crosscorrelation measurement of arrival times with relative reloca… more
Date: April 1, 2008
Creator: Foulger, G.R.; B.R. Julian, B.R. & Monastero, F.
Partner: UNT Libraries Government Documents Department
open access

Microearthquake moment tensors from the Coso Geothermal area

Description: The Coso geothermal area, California, has produced hot water and steam for electricity generation for more than 20 years, during which time there has been a substantial amount of microearthquake activity in the area. Seismicity is monitored by a high-quality permanent network of 16 three-component digital borehole seismometers operated by the US Navy and supplemented by a ~ 14-station portable array of surface three-component digital instruments. The portable stations improve focal sphere cover… more
Date: April 1, 2007
Creator: Julian, B.R.; Foulger, G.R. & Monastero, F.
Partner: UNT Libraries Government Documents Department
open access

Linear-discontinuous Galerkin approximation for the continuous-slowing-down operator

Description: A linear-discontinuous Galerkin treatment is developed for the continuous-slowing-down operator. Multigroup Legendre coefficients are derived which allow this treatment to be implemented in standard S/sub n/ codes. A synthetic acceleration scheme is developed to accelerate the outer iterations required by this treatment. A computational comparison between a first-order multigroup treatment, the diamond-difference treatment, and the linear-discontinuous treatment is given. 13 references, 6 figur… more
Date: January 1, 1985
Creator: Lazo, M.S. & Morel, J.E.
Partner: UNT Libraries Government Documents Department
open access

Convergence of linear programming using a Hopfield net

Description: Hopfield nets are interconnected networks of simple analog Processors. Such networks have been applied to a variety of optimization problems including linear programming problems. We revised the energy function used in a Hopfield net such that the network can be implemented on a digital computer to solve linearing programming problems. We also proved that the revised discrete Hopfield net coverages, and gave the conditions of convergence. The approach is tested on two large and sparse linear pr… more
Date: November 1, 1990
Creator: Lu, Shin-yee & Berryman, J.G.
Partner: UNT Libraries Government Documents Department
open access

Portable parallel programming in a Fortran environment

Description: Experience using the Argonne-developed PARMACs macro package to implement a portable parallel programming environment is described. Fortran programs with intrinsic parallelism of coarse and medium granularity are easily converted to parallel programs which are portable among a number of commercially available parallel processors in the class of shared-memory bus-based and local-memory network based MIMD processors. The parallelism is implemented using standard UNIX (tm) tools and a small number… more
Date: January 1, 1989
Creator: May, E.N.
Partner: UNT Libraries Government Documents Department
open access

Parallel superconvergent multigrid

Description: We describe a class of multiscale algorithms for the solution of large sparse linear systems that are particularly well adapted to massively parallel supercomputers. While standard multigrid algorithms are unable to effectively use all processors when computing on coarse grids, the new algorithms utilize the same number of processors at all times. The basic idea is to solve many coarse scale problems simultaneously, combining the results in an optimal way to provide an improved fine scale solut… more
Date: January 1, 1987
Creator: Frederickson, P.O. & McBryan, O.A.
Partner: UNT Libraries Government Documents Department
open access

ROCKY: an energy-environment model of coal and electricity supple in Rocky Mountain West. [Rocky Mountain states]

Description: The Rocky Mountain states of the American West are frequently cited as a potential breadbasket of domestic energy resources. This eight-state region contains about half of the US coal reserves, most of the high-grade uranium ores, almost all of the prime-grade oil shale deposits, and very large reservoirs of geothermal energy. In addition, existing oil and gas production contributes significantly to national production, and the potential for solar applications seems substantial. Understandably,… more
Date: January 1, 1979
Creator: Bivins, R.; Kolstad, C.; Loose, V.; Pendley, R. & Stein, M.
Partner: UNT Libraries Government Documents Department
open access

Technological-economic models for energy analysis

Description: The energy system and economic models described in this paper are designed for general usage in government and industry. Most energy-policy issues and decisions involve a complex mix of technical, economic, environmental, and social value considerations. Specific policy actions addressing any one of these elements can have significant effects on the others, frequently in direct conflict with other policy objectives. Many of the important attributes of energy policy, such as resource requirement… more
Date: January 1, 1978
Creator: Hoffman, K C
Partner: UNT Libraries Government Documents Department
open access

A comparative analysis of energy demand and expenditures by minority and majority households within the context of a conditional demand system

Description: Analysis and evaluation of the impact that programs and policies have on energy consumption and expenditures are confounded by many intervening variables. A clear understanding of how these variables influence energy consumption patterns should be grounded in a rigorously developed framework. In this regard much is documented in the literature. However, an analysis of the comparative relationship between energy demand and variables which influence it among different socioeconomic groups has not… more
Date: January 1, 1992
Creator: Poyer, D. A.
Partner: UNT Libraries Government Documents Department
open access

Applications of Optimal Building Energy System Selection and Operation

Description: Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation p… more
Date: April 1, 2011
Creator: Marnay, Chris; Stadler, Michael; Siddiqui, Afzal; DeForest, Nicholas; Donadee, Jon; Bhattacharya, Prajesh et al.
Partner: UNT Libraries Government Documents Department
open access

Analysis of error floor of LDPC codes under LP decoding over the BSC

Description: We consider linear programming (LP) decoding of a fixed low-density parity-check (LDPC) code over the binary symmetric channel (BSC). The LP decoder fails when it outputs a pseudo-codeword which is not a codeword. We propose an efficient algorithm termed the instanton search algorithm (ISA) which, given a random input, generates a set of flips called the BSC-instanton and prove that: (a) the LP decoder fails for any set of flips with support vector including an instanton; (b) for any input, the… more
Date: January 1, 2009
Creator: Chertkov, Michael; Chilappagari, Shashi; Vasic, Bane & Stepanov, Mikhail
Partner: UNT Libraries Government Documents Department
open access

Optimization Strategies for the Vulnerability Analysis of the Electric Power Grid

Description: Identifying small groups of lines, whose removal would cause a severe blackout, is critical for the secure operation of the electric power grid. We show how power grid vulnerability analysis can be studied as a mixed integer nonlinear programming (MINLP) problem. Our analysis reveals a special structure in the formulation that can be exploited to avoid nonlinearity and approximate the original problem as a pure combinatorial problem. The key new observation behind our analysis is the correspond… more
Date: November 13, 2007
Creator: Pinar, A.; Meza, J.; Donde, V. & Lesieutre, B.
Partner: UNT Libraries Government Documents Department
open access

Concentrating Solar Deployment System (CSDS) -A New Model for Estimating U.S. Concentrating Solar Power (CSP) Market Potential

Description: This paper presents the Concentrating Solar Deployment System Model (CSDS). CSDS is a multiregional, multitime-period, Geographic Information System (GIS), and linear programming model of capacity expansion in the electric sector of the United States. CSDS is designed to address the principal market and policy issues related to the penetration of concentrating solar power (CSP) electric-sector technologies. This paper discusses the current structure, capabilities, and assumptions of the model. … more
Date: April 1, 2006
Creator: Blair, N.; Mehos, M.; Short, W. & Heimiller, D.
Partner: UNT Libraries Government Documents Department
open access

On the Red-Blue Set Cover Problem

Description: Both the increased complexity of integrated circuits, resulting in six or more levels of integration, and the increasing use of flip-chip packaging have driven the development of integrated circuit (IC) failure analysis tools that can be applied to the backside of the chip. Among these new approaches are focused ion beam (FIB) tools and processes for performing chip edits/repairs from the die backside. This paper describes the use of backside FIB for a failure analysis application rather than f… more
Date: July 28, 1999
Creator: Carr, Robert D.; Doddi, Srinivas; Konjevod, Goran & Marathe, Madhav
Partner: UNT Libraries Government Documents Department
open access

A New Bound for the Ration Between the 2-Matching Problem and Its Linear Programming Relaxation

Description: Consider the 2-matching problem defined on the complete graph, with edge costs which satisfy the triangle inequality. We prove that the value of a minimum cost 2-matching is bounded above by 4/3 times the value of its linear programming relaxation, the fractional 2-matching problem. This lends credibility to a long-standing conjecture that the optimal value for the traveling salesman problem is bounded above by 4/3 times the value of its linear programming relaxation, the subtour elimination pr… more
Date: July 28, 1999
Creator: Boyd, Sylvia & Carr, Robert
Partner: UNT Libraries Government Documents Department
open access

Strengthening Integrality Gaps for Capacitated Network Design and Covering Problems

Description: A capacitated covering IP is an integer program of the form min{l_brace}ex{vert_bar}Ux {ge} d, 0 {le} x {le} b, x {element_of} Z{sup +}{r_brace}, where all entries of c, U, and d are nonnegative. Given such a formulation, the ratio between the optimal integer solution and the optimal solution to the linear program relaxation can be as bad as {parallel}d{parallel}{sub {proportional_to}}, even when U consists of a single row. They show that by adding additional inequalities, this ratio can be imp… more
Date: July 28, 1999
Creator: Carr, Robert D.; Fleischer, Lisa K.; Leung, Vitus J. & Phillips, Cynthia A.
Partner: UNT Libraries Government Documents Department
open access

On-Off Minimum-Time Control With Limited Fuel Usage: Global Optima Via Linear Programming

Description: A method for finding a global optimum to the on-off minimum-time control problem with limited fuel usage is presented. Each control can take on only three possible values: maximum, zero, or minimum. The simplex method for linear systems naturally yields such a solution for the re-formulation presented herein because it always produces an extreme point solution to the linear program. Numerical examples for the benchmark linear flexible system are presented.
Date: September 1, 1999
Creator: DRIESSEN,BRIAN
Partner: UNT Libraries Government Documents Department
open access

Characterizing and modeling subarea-level energy transactions.

Description: This paper describes the application of an electrical network characterization method to an optimization model that is designed to simulate subarea-level energy transactions. The network characterization method determines subarea clusters of system buses that electrically respond to perturbations in a very similar manner. The method produces a reduced number of transmission constraints and preserves parallel path representations. The least-cost, linear programming (LP) formulation takes advanta… more
Date: March 5, 1998
Creator: Kavicky, J. A.
Partner: UNT Libraries Government Documents Department
open access

Parametric integer linear programming: a synthesis of branch and bound with cutting planes

Description: A branch and bound algorithm is designed to solve the general integer linear programing problem with parametric right-hand sides. The right-hand sides have the form b + THETA d, where b and d are conformable vectors, d consists of nonegative constants, and THETA varies from zero to one. The method consists of first determining all possible right-hand side ineger constants and appending this set of integer constants to the initial tableau to form an expanded problem with a finite number of famil… more
Date: January 1, 1980
Creator: Rountree, S.L.K. & Gillett, B.E.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen