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91.
W. Kleiböhmer 《Accreditation and quality assurance》1999,4(12):517-520
Maintaining a high quality of research and development (R&D) is fundamental for the competitiveness of European industry.
The development of new technologies and the improvement of existing technologies, products, production processes, measurement
instrumentation and methods as well as basic research is essential. The objective of the workshop on "Quality Management in
Analytical Chemical Research and Development" was to bring together experts from the academic world, industrial and institutional
laboratories and also accreditation bodies to discuss the actual state of the art in the field of quality management in R&D,
and to set up milestones for further activities. Furthermore, an important objective was to present the EURACHEM/CITAC Guide
2. The paper outlines the programme of the workshop and summarises the round-table discussions and expert recommendations.
Most of the contributions to the round-table discussions will be published as full papers in a forthcoming issue of Accreditation
and Quality Assurance. The workshop was organised by the Institut für Chemo- und Biosensorik (ICB), Münster, with the financial
support of the SMT-Programme of the European Commission (Contract No.: SMT4-CT98-6534). 相似文献
92.
Klaus Reber 《Accreditation and quality assurance》1999,4(4):156-157
The Swiss Federal Laboratories for Materials Testing and Research (EMPA) have established a quality assurance system based
on EN 45001 which meets the requirements for accreditation of all EMPA's testing activities. As testing is only a part of
EMPA's range of activities, and is performed in decentralised departments, the system does not satisfy the management needs.
The fundamental reorganisation of EMPA's St. Gallen site was used as an opportunity to implement an overall process-oriented
management system which also included quality and the needs for accreditation. Later, an environmental management system was
added and then certified for ISO 9001 and 14001. The system consists of a "Management Manual" for the St. Gallen site and
a customised "Quality Manual" for each department. One of the key elements is a comprehensive review and planning procedure
covering all business aspects. 相似文献
93.
效益滞后是经理人员工作的基本性质,文章以信息经济学为理论基础,并采用信息论的方法对经理人员工作效益滞后性的内在原因和机制进行了深入的探讨,然后用控制论的方法对决策滞后系统建模,并作进一步分析。 相似文献
94.
A multiple objective waste-disposal model is developed and analysed. The model is a modification of the single objective waste-disposal model of Alley, Aguado and Remson. The solution structure is obtained using the method of constraints so that dual variables (shadow prices) are available with the solutions. 相似文献
95.
Tasuku?ToyonagaEmail author Takesh?Itoh Hiroaki?Ishii 《Fuzzy Optimization and Decision Making》2005,4(1):51-69
The main purpose of this paper is to present a crop planning problem for agricultural management under uncertainty. It is significant that agricultural managers assign their limited farmlands to cultivation of which crops in a season. This planning is called the crop planning problem and influences their incomes for the season. Usually, the crop planning problem is formulated as a linear programming problem. But there are many uncertain factors in agricultural problems, so future profits for crops are not certain values. A linear programming model with constant profit coefficients may not reflect the environment of decision making properly. Therefore, we propose a model of crop planning with fuzzy profit coefficients, and an effective solution procedure for the model. Furthermore, we extend this fuzzy model, setting the profit coefficients as discrete randomized fuzzy numbers. We show concrete optimal solutions for each models. 相似文献
96.
We consider two stochastic equations that describe the turbulent transfer of a passive scalar field (x)(t,x) and generalize the known Obukhov–Kraichnan model to the case of a possible compressibility and large-scale anisotropy. The pair correlation function of the field (x) is characterized by an infinite collection of anomalous indices, which have previously been found exactly using the zero-mode method. In the quantum field formulation, these indices are identified with the critical dimensions of an infinite family of tensor composite operators that are quadratic in the field (x), which allows obtaining exact values for the latter (the values not restricted to the -expansion) and then using them to find the corresponding renormalization constants. The identification of the correlation function indices with the composite-operator dimensions itself is supported by a direct calculation of the critical dimensions in the one-loop approximation. 相似文献
97.
笔者依据所能获得的资料———《瓶罐玻璃行业企业经济信息汇编》[6],建立了一套经济实用的瓶罐玻璃行业企业绩效评价指标体系;提供了一种科学评价方法和计算机化的评价技术;能适时地对该行业内各企业绩效进行评价和比较分析;及时获得各企业在全行业内竞争位次;及时发现影响企业绩效的主要因素;为高层管理者制定和调整企业管理决策提供了参考依据。 相似文献
98.
“调配问题”的动态规划模型与计算 总被引:1,自引:0,他引:1
本给出了调配问题的动态规划模型与计算,该表征更具一般化,且便于计算机计算。 相似文献
99.
Stochastic Lagrangian Relaxation Applied to Power Scheduling in a Hydro-Thermal System under Uncertainty 总被引:3,自引:0,他引:3
A dynamic (multi-stage) stochastic programming model for the weekly cost-optimal generation of electric power in a hydro-thermal generation system under uncertain demand (or load) is developed. The model involves a large number of mixed-integer (stochastic) decision variables and constraints linking time periods and operating power units. A stochastic Lagrangian relaxation scheme is designed by assigning (stochastic) multipliers to all constraints coupling power units. It is assumed that the stochastic load process is given (or approximated) by a finite number of realizations (scenarios) in scenario tree form. Solving the dual by a bundle subgradient method leads to a successive decomposition into stochastic single (thermal or hydro) unit subproblems. The stochastic thermal and hydro subproblems are solved by a stochastic dynamic programming technique and by a specific descent algorithm, respectively. A Lagrangian heuristics that provides approximate solutions for the first stage (primal) decisions starting from the optimal (stochastic) multipliers is developed. Numerical results are presented for realistic data from a German power utility and for numbers of scenarios ranging from 5 to 100 and a time horizon of 168 hours. The sizes of the corresponding optimization problems go up to 200000 binary and 350000 continuous variables, and more than 500000 constraints. 相似文献
100.
The nonlinear Schrödinger equation which governs the dynamics of two-dimensional spatial solitons in Kerr media with periodically varying diffraction and nonlinearity has been analyzed in this paper using variational approach and numerical studies. Analytical expressions for soliton parameters have been derived using variational analysis. Variational equations and partial differential equation have been simulated numerically. Analytical and numerical studies have shown that nonlinearity management and diffraction management stabilize the pulse against decay or collapse providing undisturbed propagation even for larger energies of the incident beam. 相似文献