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21.
This paper presents a technique for the solution of scheduling problems encountered in a printing company that can be applied to a range of practical industrial problems. The aim of the research was to develop a due date scheduling algorithm within the framework of the scheduling system already in use by the company. The objective was to enable jobs to be scheduled as close to their due dates as possible, while ensuring that the resultant schedule was feasible with respect to work centre capacities and earliest start date constraints.  相似文献   
22.
Environmental matrices including soils, sediments, and living organisms are reservoirs of several essential as well as non-essential elements. Accurate qualitative and quantitative information on the distribution and interaction of biologically significant elements is vital to understand the role of these elements in environmental and biological samples. Synchrotron micro-X-ray fluorescence (μ-SXRF) allows in situ mapping of biologically important elements at nanometer to sub-micrometer scale with high sensitivity, negligible sample damage and enable tuning of the incident energy as desired. Beamlines in the synchrotron facilities are rapidly increasing their analytical versatility in terms of focusing optics, detector technologies, incident energy, and sample environment. Although extremely competitive, it is now feasible to find stations offering complimentary techniques like micro-X-ray diffraction (μ-XRD) and micro-X-ray absorption spectroscopy (μ-XAS) that will allow a more complete characterization of complex matrices. This review includes the most recent literature on the emerging applications and challenges of μ-SXRF in studying the distribution of biologically important elements and manufactured nanoparticles in soils, sediments, plants, and microbes. The advantages of using μ-SXRF and complimentary techniques in contrast to conventional techniques used for the respective studies are discussed.  相似文献   
23.
With the rapid development of computer technology, the research on complex networks has attracted more and more attention. At present, the research directions of cloud computing, big data, internet of vehicles, and distributed systems with very high attention are all based on complex networks. Community structure detection is a very important and meaningful research hotspot in complex networks. It is a difficult task to quickly and accurately divide the community structure and run it on large-scale networks. In this paper, we put forward a new community detection approach based on internode attraction, named IACD. This algorithm starts from the perspective of the important nodes of the complex network and refers to the gravitational relationship between two objects in physics to represent the forces between nodes in the network dataset, and then perform community detection. Through experiments on a large number of real-world datasets and synthetic networks, it is shown that the IACD algorithm can quickly and accurately divide the community structure, and it is superior to some classic algorithms and recently proposed algorithms.  相似文献   
24.
Customer requirements play a vital and important role in the design of products and services. Quality Function Deployment (QFD) is a popular, widely used method that helps translate customer requirements into design specifications. Thus, the foundation for a successful QFD implementation lies in the accurate capturing and prioritization of these requirements. This paper proposes and tests the use of an alternative framework for prioritizing students’ requirements within QFD. More specifically, Fuzzy Analytic Hierarchy Process (Fuzzy-AHP) and the linear programming method (LP-GW-AHP) based on Data Envelopment Analysis (DEA) are embedded into QFD (QFD-LP-GW-Fuzzy AHP) in order to account for inherent subjectivity of human judgements. The effectiveness of the proposed framework is assessed in capturing and prioritizing students’ requirements regarding courses’ learning outcomes within the process of an academic course design. Sensitivity analysis evaluates the robustness of the prioritization solution and implications for course design specifications are discussed.  相似文献   
25.
在单目标、单约束条件下,建立了三状态并-串联系统的优化模型,采用选取重要部件的方法优化系统可靠度,并相应地给出优化算法,最后通过例子,验证了该算法的有效性.  相似文献   
26.
湖南省企业生命周期测度及其影响因素分析   总被引:1,自引:0,他引:1  
本文运用生命表方法对湖南省1980年-2007年期间新成立企业的生存状况进行了测度和分析,通过考察企业生存时间的分位数、在指定时间的平均剩余寿命和在指定时间内的平均存活时间等指标,对不同城、行业、资本规模、所有制类型和成立时间的企业进行了比较研究。结果表明,不同城市、行业、资本规模、所有制类型和成立时间的企业生存时间存在较大差异,我国企业生存状况不仅受到西方传统产业组织理论中企业所在地域、行业和规模的影响,还受到由中国国情所决定的所有制性质和成立时间的影响。  相似文献   
27.
利用中国16个高技术行业的面板数据,对高技术行业的技术创新影响因素进行了实证分析,不仅研究了R&D投入对高技术行业技术创新的影响,还考虑了行业融资结构、外资企业研发的技术溢出效应、产权结构、企业规模以及市场集中度等因素的影响作用.  相似文献   
28.
We study the Cauchy problem for the difference-differential equation
  相似文献   
29.
论述了宁波GDP与第一、二、三产业的关联度.根据实证分析的结果,得出宁波的国民经济增长已从改革开放初期主要依靠第一、第二产业支撑,演变到目前主要依靠第二、第三产业共同推动.在此基础上,提出要大力发展第三产业,促进宁波经济稳健增长.  相似文献   
30.
It is necessary to develop new engineering-directed applied chemistry major on the basis of chemistry major and to remodel the current applied chemistry education according to the concept of emerging engineering. Herein, emendation in 2020 version of applied chemistry education plan and researches on teaching renovations for applied chemistry major in Hunan University is introduced. Through the adjustments of education goals, course systems, teaching contents and teaching models, we wish to highlight the central status of the educations that integrates morality and ability. In addition to the inheritance of the specialty in corrosion and protection, it is expected to further satisfy the need of graduates for the industries such as new materials, new energy, high-tech production, environmental protection, and new generation of information technique. At last, future trends and perspectives in emerging engineering applied chemistry is proposed.  相似文献   
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