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81.
摘要:压力是气井和气藏生产动态分析的灵魂,很多动态分析方法都与压力有着直接的联系。然而,由于致密低渗透气藏产量低、压力下降快、关井压力恢复缓慢等生产特征,以及生产方式的限制,在生产过程中很难获得气井或气藏地层压力资料。压降法、产量不稳定分析法和产量递减曲线分析方法是气藏常用的气井生产动态分析方法,但由于地层压力资料缺乏,压降法和产量不稳定分析法也都受到了很大的限制,在衰减递减曲线分析方法的基础上对其进行修正,摆脱了压力资料的限制,通过和压降法对比分析,验证了修正衰减曲线分析方法在生产动态分析中的可靠性。  相似文献   
82.
Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper.  相似文献   
83.
本文从社会形态理论的前提出发,以马克思社会形态理论的视域为主线,研究了马克思视域内的社会形态理论,即生产力视域内的社会形态理论、生产方式视域内的社会形态理论和人的发展视域内的社会形态理论以及三者之间的递进关系。生产方式视域以生产力视域为基础,但又不限于生产力视域,人的发展视域以生产方式视域为基础,但又不限于生产方式视域,从而得出马克思视域内的社会形态的概念。一方面,中国社会主义社会形态建立、建设和改革开放的实践,为我们准确全面地认识马克思视域内的社会形态理论创造了条件;另一方面,新世纪、新实践和新任务要求中国人重新准确地全面地把握马克思视域内的社会形态理论。  相似文献   
84.
The traditional Cobb–Douglas production function uses the compact mathematical form to describe the relationship between the production results and production factors in the production technology process. However, in macro-economic production, multi-structured production exists universally. In order to better demonstrate such input–output relation, a composite production function model is proposed in this article. In aspect of model parameter estimation, artificial fish swarm algorithm is applied. The algorithm has satisfactory performance in overcoming local extreme value and acquiring global extreme value. Moreover, realization of the algorithm does not need the gradient value of the objective function. For this reason, it is adaptive to searching space. Through the improved artificial fish swarm algorithm, convergence rate and precision are both considerably improved. In aspect of model application, the composite production function model is mainly used to calculate economic growth factor contribution rate. In this article, a relatively more accurate calculating method is proposed. In the end, empirical analysis on economic growth contribution rate of China is implemented.  相似文献   
85.
L'essor des chaînes d'approvisionnement mondiales (CAM) éloigne l'emploi de la demande, géographiquement et sectoriellement. Pour mieux comprendre le phénomène, les auteurs mesurent l'emploi lié aux CAM selon sa localisation et celle de la demande, en se fondant sur les données de la base WIOD et en complétant les estimations déjà présentées par le BIT. L'analyse porte sur la période 1995–2013 et sur 40 économies. Elle montre que la Chine, principale bénéficiaire de la demande liée aux CAM autrefois, contribue maintenant à l'alimenter, tout comme les relations de production entre économies émergentes. En outre, le poids des services liés à une demande manufacturière augmente.  相似文献   
86.
In electronics Fabs such as semiconductor Fabs and liquid crystal display (LCD) Fabs, which are capital-intensive, finite-capacity planning is critical to achieving full-capacity production and on-time production. However, existing finite-capacity planning methods do not adequately reflect the actual capacity profiles of an electronics Fab. In this paper, we propose a new Fab-level capacity-filtering procedure to generate finite-capacity plan: a backward capacity-filtering procedure for generating finite-capacity release plan. When developing the Fab-level filtering procedures, we use stage-level capacity-filtering algorithms as a key building block. In this study, we enhance the previous capacity-filtering algorithms proposed by one of the authors in order to facilitate the practical requirements of electronics Fabs. We apply the proposed capacity-filtering method to a modern LCD–TFT Fab in Korea. Performance analyses demonstrate that the proposed method is superior to existing methods.  相似文献   
87.
高含水期陆相复杂断块层状油藏剩余油分布复杂,油藏模拟难度大。马11复杂断块油藏在油藏精细描述基础上,利用动静态综合分析研究与密网格大规模数值模拟研究相结合,提高了剩余油研究精度和可信度;在此基础上,针对油藏剩余油分布特点并结合当前经济技术条件,部署实施了以调整井、调剖、堵水、油水井大修为主的剩余油挖潜方案,油藏含水上升率大幅度下降、采油速度上升、采收率提高了。  相似文献   
88.
Abstract

Purpose: This paper presents a combined multi-phase supplier selection model. The process repeatedly revisits the criteria and sourcing decision as the development process continues. This enables a structured adoption of product and production system innovation from strategic suppliers, where previously the literature purely focuses on product innovation or cost reduction. Design/methodology/approach: The authors adopted an embedded researcher style, inductive, qualitative case study of an industrial supply cluster comprising a focal automotive company and its interaction with three different strategic stamping suppliers. Findings: Our contribution is the multi-phased production and product innovation process. This is an advance from traditional supplier selection and also an extension of ideas of supplier-located product development as it includes production system development, and complements the literature on working with strategic suppliers. Specifically, we explicitly articulate the previously unreported issue of whether a supplier chosen for its innovation capabilities at the start of the new product development process will also be the most appropriate supplier during the production system development phase, when an ability to work collaboratively may be the most important attribute, or in the large-scale production phase when an ability to manufacture at low unit cost may be most important. Originality/value: The paper identifies a multi-phase approach to tendering within a fixed body of strategic suppliers which seeks to identify the optimum technological and process decisions as well as the traditional supplier sourcing choice. These areas have not been combined before and generate a valuable approach for firms to adopt as well as for researchers to extend our understanding of a highly complex process.  相似文献   
89.
Through a meta‐literature review, this paper examines the changing contours of Chinese sociology of homosexuality in contemporary China. It unfolds the different theoretical orientations and methodologies that construct the modern male homosexual subject under major socio‐economic and political changes. Chinese sociology of homosexuality started in the reform era and has been dominated by Western knowledge production and the political ideology of the communist party‐state. Fused with the bio‐medical model and the state's modernization project in the 1980s–1990s, the sociological study adopted a functionalist and positivistic approach with survey‐based methodology in the main which focused on the etiology of homosexuality. A new transnational knowledge production of sociology of homosexuality has formed since the 2000s which has shifted towards a constructivist/ post‐structuralist approach and reflexive qualitative methodology. The new sociological study examines the rise of male (as well as female) homosexual identity in China, questions the hetero/homosexual binary and discusses how an individual makes sense of homosexual identity to form same‐sex intimate relationships. By tracing the epistemology of homosexuality in contemporary China, this paper rethinks the dominance of the Western construction and the role of the state in shaping the knowledge of homosexuality and proposes alternative spaces for theorizing Chinese sexual identities, desires and practices.  相似文献   
90.
制造业是我国国民经济的支柱产业,但也是环境污染物排放的主要来源、能源消耗主体和温室气体排放大户。制造系统高能耗、高物耗、高碳排放的加工过程是造成制造业碳排放量大的重要原因。生产单元作为制造系统的加工的主体,其碳排放量的核算是确定整个制造系统乃至制造业碳排放总量的关键。本文首先对生产单元的原材料、电能、辅助物料及废屑处理所引起的碳排放进行分析,确定生产单元的碳排放源;其次,产品合格率的不同会造成生产单元输入及输出的成品/半成品数量的差异,进而影响生产单元单位产品的碳排放量,在此基础上,综合考虑了原材料、电能、辅助物料及废屑处理的碳排放情况,构建了给定工艺流程下生产单元碳排放核算模型。最后,结合一汽车排气装置加工实例,分别核算加工过程中九个生产单元的碳排放量,验证了模型的可行性。  相似文献   
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