Emerald
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Measuring efficiencies of parallel systems with shared inputs/outputs using data envelopment analysis Purpose – The purpose of this paper is to measure the efficiencies of parallel subsystems with shared inputs/outputs. Each subsystem has not only a set of common inputs and outputs, but also some dedicated inputs and outputs as well as some shared inputs and outputs. A more general data envelopment analysis (DEA) approach is proposed to deal with this efficiency evaluation issue. Based on the proposed approach, mechanisms for shared inputs/outputs distribution and efficiency decomposition among sub-units are presented. Design/methodology/approach – To evaluate the efficiency of the parallel systems, this paper proposes a centralized DEA approach by assuming that the same input/output factor in a decision-making unit (DMU) has the same multiplier for all its sub-units. Furthermore, different proportions of shared inputs/outputs are imposed on sub-units within different DMUs in evaluating each DMU’s efficiency. The proposed approach is applied to evaluate the operational efficiencies of 18 railway firms in China. Findings – By using the proposed DEA approach, the efficiencies of the whole DMU and its sub-units can be measured at the same time, and the optimal allocation strategy of shared inputs/outputs can also be obtained. The proposed model is more reasonable and robust for measuring the operational performance of parallel systems with shared inputs and outputs. The efficiency of railway system in China is relatively low, and its inefficiency is largely caused by lower freight transportation performance. Great disparities among firms can be found in the passenger transportation efficiency and freight transportation efficiency. Research limitations/implications – This study develops the DEA model under the assumption of constant returns to scale, which can be directly extended to a situation with variable returns to scale. Practical implications – In this paper, the proposed approach is a more effective way to evaluate the efficiencies of parallel systems with shared inputs/outputs. With respect to the application, to improve the overall efficiency of China’s railway system, more efforts should be taken to improve its operational performance of freight transportation. Furthermore, firms’ disparities should also be considered when making these related policies. Originality/value – The proposed approach can evaluate the whole DMU and its sub-units at the same time. Considering simultaneously the common/dedicated/shared inputs/outputs, the proposed approach is more general than the existing approaches in the literature. In the described approach, the same type of input or output is assumed to have the same weight for all sub-units within one DMU. More importantly, the proposed model imposes different proportions of shared inputs/outputs on different DMUs’ sub-units when measuring the efficiency for each DMU.
Emerald - Tập 44 Số 3 - Trang 336-352 - 2015
Optimal green supply-chain model design considering full truckload
Purpose
Supply chain management (SCM) focuses smart logistics and quality service. Diverse elements such as design, procurement, production and sale policies are the keys to SCM efficiency. Due to worsening environmental pollution in recent years, many businesses, government agencies and consumers have become more aware of greenhouse gases (GHG) emissions. In response, the government has established new environmental regulations to control various GHG, such as CO2 and sulfur dioxide. Therefore, to reduce pollution and its adverse effects, the authors have promoted environmental concerns by developing environmental friendly policies. The purpose of this paper is to develop a multi-objective decision making model that integrates both forward and reverse logistics to determine how best to incorporate recycling and reduce manufacturing costs.
Design/methodology/approach
In this study, the authors developed a multi-objective decision-making model that integrates both forward and reverse logistics to determine how best to incorporate recycling and reduce manufacturing costs. They used the normalized normal constraint method as proposed by Messac et al. (2003) to generate a series of uniform lines on a Pareto Frontier chart.
Findings
Based on the results of this study, the authors can determine the trade-off between costs and emissions and design the most environmental-friendly and economical strategy for production.
Research limitations/implications
This study is limited to a case study on paper manufacturing.
Practical implications
The authors considered the full truckload discount policy in which buyers can reduce their purchase costs by increasing the number of full truckload product orders; this will reduce transportation costs and also minimize overall carbon emissions.
Social implications
This study encourages industries to focus on environmental friend policies and social responsibilities.
Originality/value
The authors investigated the impacts of the paper making industry on economy and environment. An increase in demand will negatively impact the environment by causing CO2 emissions to increase from higher production and the felling of more trees to provide raw materials for manufacturers (paper mills).
Emerald - Tập 48 Số 9 - Trang 2150-2174 - 2019
Next generation grids for science and industry Purpose This paper aims to review current progress towards the development of the next generation grids for science and industry with particular reference to European endeavours. Reviews of projects and initiatives in biocybernetics, biometrics and innovative research and development are given. Design/methodology/approach A general review and survey of selected research and development topics. Findings Illustrates the multi‐ and trans‐disciplinary natures of studies in cybernetics, systems, and management science with a view to further research and development activity. Practical implications The choice of reviews provides awareness of the current trends in these areas. Originality/value The reviews are selected from a global database and give a studied assessment of current research and development.
Emerald - Tập 36 Số 2 - Trang 137-143 - 2007
TOWARDS THE GENERAL THEORY OF CONCEPTUAL SYSTEMS A general theory of conceptual systems (GCST) is developed, in which the concept of systems is introduced not a priori or theoretically, but by means of a rigorous procedure, supported by experimental knowledge of these or other system realization forms (so‐called “realization” and “trajectories”). This is the stage of an inductive construction of computable concepts, i.e. “concepts”. “Concept” is presented in the form of a function of discrete variables, one part of which is known (essential variables), while the other part is independent (non‐essential variables). The presence of “concept” allows one to construct new, not yet realized “trajectories”. This is the stage of the deductive conclusion. The general principles of GCST construction on the basis of an artificial intelligence program system are formulated. This approach excludes widespread methods of a priori construction of system theories (e.g. in the “theory of usefulness”, the “study of operations”).
Emerald - Tập 3 Số 1 - Trang 17-25 - 1974
Scientific‐Technological Innovation Processes — A New Field of Applied Systems Analysis The aim of the applied systems analysis of scientific‐technological innovation is to identify the most effective innovation fields and to develop innovation strategies. This cannot be achieved without the development of theoretical foundations, practical methods and principles, a heuristic algorithm and a computer‐aided decision system. Such a system is described in this article, and represents, it is claimed, the first steps towards a computer‐aided decision system for innovation strategies.
Emerald - Tập 18 Số 1 - Trang 21-31 - 1989
On the new numerical solution of corona‐electrostatic electric field model with inductive electrostatic electrode for the industrial separation of granular mixture Purpose The purpose of this paper is to study the industrial separation of granular mixture by approximation of combined corona‐electrostatic electric field with feeder and inductive electrostatic electrode. Design/methodology/approach The original numerical method developed in Caron's Kybernetes paper is used and extended to an industrial construction. The method gives a mathematical model of an industrial process and converts the non‐linear partial derivative system into an iterative system of linear equations. Using the well‐known finite difference approximation, a numerical solution is computed very quickly. Findings In order to really obtain a computer‐aided numerical solution, it is necessary to define a really manageable approximation method. The new simulation results are detailed and show better results for the steady state in time processing and finally, to imagine improvements of the industrial processes. Originality/value The paper shows the fast numerical solution, which leads to confidence in the numerical approximations to imagine improvements of the industrial processes easily.
Emerald - Tập 38 Số 5 - Trang 819-836 - 2009
Fuzzy Symmetric Functions with Don't‐care Conditions and Applications Defines and investigates fuzzy symmetric functions with don't‐care conditions and most‐unsymmetric functions. Represents and illustrates by examples algorithms for finding the grade of membership function and the number of most unsymmetric functions. Also presents applications to function representation, data reduction and error correction. The results may have useful applications to fuzzy logics, finding most‐unsymmetric images, fuzzy neural networks and related areas.
Emerald - - 1993
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