1,800,779 research outputs found
A NOTE ON FIXING MISBEHAVING MATHEMATICAL PROGRAMS: POST-OPTIMALITY PROCEDURES AND GAMS-RELATED SOFTWARE
Get PDFMathematical programming formulations can yield faulty answers. Models can be unbounded, infeasible, or optimal with unrealistic answers. This article presents techniques for theory-based discovery of the cause of faulty models. The approaches are demonstrated in the context of linear programming. They have been computerized and interfaced using the General Algebraic Modeling System (GAMS), and are distributed free of charge through new GAMS versions and an outline web page.Debugging, GAMS software, Mathematical programming, Research Methods/ Statistical Methods,
Complementarity Problems in GAMS and the PATH Solver
Get PDFA fundamental mathematical problem is to find a solution to a
square system of nonlinear equations. There are many methods to
approach this problem, the most famous of which is Newton?s method.
In this paper, we describe a generalization of this problem, the complementarity
problem. We show how such problems are modeled within
the GAMS modeling language and provide details about the PATH
solver, a generalization of Newton?s method, for finding a solution.
While the modeling format is applicable in many disciplines, we draw
the examples in this paper from an economic background. Finally,
some extensions of the modeling format and the solver are described
GAMS code for estimating a social accounting matrix (SAM) using cross entropy methods (CE)
Get PDFThis paper documents the computer code implementing the CE-SAM estimation technique in GAMS (General Algebraic Modeling System). It defines the estimation problem in a deterministic setting; extends the approach to include a stochastic treatment of errors in control totals; summarizes the equations describing CE technique for estimating a consistent SAM starting from an inconsistent data set estimated with error; and provides the GAMS code.Social accounting. ,Stochastic analysis. ,Mathematical models. ,TMD ,
Formulating and Solving Exhaustible Resource Models as Mixed Complementarity Problems in GAMS
Get PDFIn this paper a formulation of dynamic non-linear programs as mixed complementarity problems (mcp) is shown. Models of exhaustible resource markets are used to describe the transformation. Once the mixed complementarity formulation is developed, the implementation in GAMS is described in detail.
Cross-Validation, Support Vector Machines and Slice Models
Get PDFWe show how to implement the cross-validation technique used in ma-
chine learning as a slice model. We describe the formulation in terms of support
vector machines and extend the GAMS/DEA interface to allow for e cient solu-
tions of linear, mixed integer and simple quadratic slice models under GAMS
Los hongos de colombia – viii some new species of soil fungi from colombia
No full textThree new Colombian microfungi are described. Trichoderma inhamatum Veerkamp and amp; W. Gams and Rhinocladiella phaeophora Veerkamp and amp; W. Gams were isolated from a maizefield soil near Acacías, Dep. Meta, at 500 m alt.; Mortierella ornata W. Gams was isolated from a soil sample from mountain forest, Parque Nacional del Puracé, Cauca-Huila, at 3.100 m alt.Tres nuevos hongos colombianos son descritos: Trichoderma inhamatum Veerkamp and amp; W. Gams y Rhinocladiella phaeophora Veerkamp and amp; W. Gams fueron aislados de una muestra de suelo agrario (campo de maíz) vecino de Acacías, Dep. del Meta, a 500 m de altitud; Mortierella ornata W. Gams fue aislada de una muestra de suelo de bosque andino, Parque Nacional delPuracé, Cauca-Huila, a 3.100 m de altitud
Exercises in general equilibrium modeling using GAMS and key to exercises in CGE modeling using GAMS
No full textThis easy-to-use manual presents exercises related to computable general equilibrium (CGE) models, which represent one type of economywide model used in policy analysis. This type of model explicitly recognizes that changes affecting one part of the economy can have repercussions throughout the rest of the economy. They are particularly useful in capturing the indirect effects of a policy change. This manual is designed to help the reader construct, modify, and conduct food policy simulations using GAMS (General Algebraic Modeling System), one of the most popular softwares for solving CGE models. The model that is developed in the concluding exercise provides a starting point for applied policy analysis. A supplement to the manual provides the keys to the exercises. The manual also comes with a CD-ROM with a limited-capacity version of GAMS and a diskette with help files." -- from Editors' IntroductionPRIFPRI1; IFPRI1 training; TCSPTM
Using the Mathcad Solver to Teach Portfolio Optimisation
Get PDFThis paper introduces a Mathcad program for teaching optimisation. The program, which involves a portfolio of equity shares, is less code oriented than GAMS and reinforces mathematical notation to a greater extent than the Excel solver. Also, the program adjusts automatically for alternative portfolios (other than the one presented) without the need for further programming. Thus, students can concentrate on examining alternative portfolios with little need to change parameters consistently.
STRESS ANALYSIS IN THE SELECTED ORGANIZATION
Get PDFStres je vse večji problem današnjega časa po celem svetu. Stres vsak doživlja drugače, večinoma pa se odraža v čustvenih, telesnih in vedenjskih odzivih. Stresu se ne moremo izogniti, lahko ga le omilimo na različne načine.
Stres na delovnem mestu je eden glavnih težav v organizacijah. Stres na delovnem mestu je zelo pogost pojav, zato je pomembno, da organizacije pravi čas in pravilno uporabljajo metode ali programe za preprečevanje in premagovanje stresa. Delavec, ki je pod stresom, je manj produktiven in pogosteje odsoten z dela zaradi bolezni, kar pripelje do stroškov organizacije.
Raziskava, ki smo jo opravili med zaposlenimi v izbrani organizaciji, je pokazala, da so zaposleni pri delu preobremenjeni, kar pripelje do simptomov, kot so negotovost, napetost in pozabljivost. Zaposleni poznajo načine premagovanja stresa, vendar jih v večini ne izvajajo. Prav tako, pa so zaposleni v izbrani organizaciji nezadovoljni z organizacijo in njenimi načini premagovanja stresa, ker jih izvaja zelo redko ali nikoli. Menimo, da bi stanje v podjetju lahko izboljšala organizacija sama, če bi se bolj potrudila in s predlaganimi programi za premagovanje stresa, le - tega v organizaciji tudi zmanjšala.Stress is a growing problem in today\u27s worldwide. Stress experienced each other, but mostly reflects the emotional, physical and behavioral responses. Stress is unavoidable, you can only mitigate different ways.
Stress at work is one of the main problems in organizations. Stress in the workplace is a very common phenomenon, it is important that organizations the right time and correct methods or programs to prevent and overcome stress. A worker who is under stress, is often sick and less productive, leading to the cost of organizing
A survey we conducted among employees in the selected organization has shown that employees are overwhelmed at work, leading to symptoms such as insecurity, stress and forgetfulness. Employees know the ways of overcoming stress, but most do not. Also, are employed in selected organization of frustration with the organization and its ways of managing stress because they are performed rarely or never. We believe that the situation in the company can improve the organization itself, if it is a more try and the proposed programs for stress, stress in the organization also reduced
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