马克思主义地理环境论与区域生态文明建设

马克思主义地理环境论应该包括马克思恩格斯人与自然、人与社会关系的理论和自然-人-社会相互作用的物质变换理论以及从普列汉诺夫地理环境论到科学发展观等马克思主义继承者的理论成果。构建区域生态文明的过程既需要上述理论助力顶层设计宏观决策,又离不开它进行具体问题具体分析攻坚克难。具体而言就是,需要在马克思主义地理环境论的指导下,从区域自然地理环境和社会人文环境实际出发,注重区域空间的平衡稳定、区域主体的和谐共生、区域资源的科学配置,从而创造出自然-人-社会“三位一体”的全新的生态文明主体的存在方式和生活方式。     

Planned Lead Times in Multistage Systems

This study investigates the impact of planned lead times on performance in multistage manufacturing where material requirements planning is used in a make-to-stock environment. We simulate a variety of different operating environments and find: (1) planned lead times are important to customer service levels under all operating environments examined, but have a smaller impact on inventory investment; (2) tight due dates introduced by short planned lead times hurt customer service without saving much inventory; (3) small increases to tight planned lead times improve customer service substantially with small inventory increases; (4) co-component inventories change with planned lead times, and disparity between such inventories is a sign of poor timing coordination; (5) the fixed order quantity rule performs better than the periodic order quantity rule; and (6) tall product structure and large lot sizes require particular attention to planned lead times. The findings also extend the current understanding of planned lead times by including uncertainties such as forecast error, yield loss, and equipment reliability. The study concludes with a way to diagnose and improve poorly set planned lead times.     

Simulation Analysis of a Manufacturing Supply Chain*

A supply chain is a series of manufacturing plants that transform raw material into finished product. A pipeline within a supply chain refers to the stream of information, material, components, and assemblies that are associated with a particular product. It is typical for manufacturing plants to put considerable effort to optimize the performance of a horizontal slice of a supply chain (such as coordination among parts that share a common resource). The need to optimize the performance of the vertical slice (the supply chain connecting raw material to finished product) by controlling the transmission of schedule instability and the resulting inventory fluctuation is often overlooked. A schedule is stable if actual production requirements for a given period do not change from the forecast production requirements. Stable production schedules are important when managing supply chains as they help control inventory fluctuation and inventory accumulation. Failure to control schedule instability results in high average inventory levels in the system. In this paper a simulation analysis of supply chain instability and inventory is conducted, and it is shown how supply chains can be analyzed for continuous improvement opportunities using simulation. The focus is on a stamping pipeline in an automobile supply chain based on operating data from General Motors (GM). It is shown that the techniques used in this paper are a useful tool for supply chain analysis.     

论形上迷失与异化劳动

形上迷失即终极关怀的缺失,它的内在原因是人的意识,但意识在人类诞生之初仅提供给形上迷失以先在的前提条件,真正导致形上迷失产生的是把人类从他的物质家园———自然中分离出去的异化劳动。在异化劳动的推动下形上迷失跨越史前时代、古代文明和轴心期这三个历史阶段,从偶然的可能开始经由现实的可能最终达到其完全的现实。与此同时在轴心期,人类的精神家园也随之而彻底建立。     

A New Framework for Manufacturing Planning and Control Systems*

This paper presents a new framework for manufacturing planning and control systems which we call iterative manufacturing planning in continuous time (IMPICT) that appears to have several advantages over the well-known material requirements planning (MRP) framework. IMPICT explicitly considers capacity constraints and total system cost (including tardiness) to determine order sizes, order release/due dates, and operation schedules in a deterministic, multi-level, finite horizon, dynamic demand environment. Continuous time scheduling variables allow setups to be carried over from one period to the next. Three new heuristics built on the IMPICT framework are presented and tested in a simulation-based, full-factorial experiment with a wide variety of problem environments. The benchmark for the experiment was materials requirements planning with operations sequencing (MRP/OS) implemented with best-case, fixed planned lead times. The experiment showed that all three heuristics were statistically better than MRP/OS. The total cost for the order merging (OM) heuristic was 25 percent better than the total cost for MRP/OS. Computational times for OM were substantially larger than for MRP/OS; however, the computational times in the experiment suggest that OM is still computationally viable for large-scale batch manufacturing environments found in industry. IMPICT is superior to standard MRP systems because it explicitly considers capacity constraints and total system costs when it creates a materials plan. IMPICT is superior to linear programming-based approaches to finite loading and scheduling found in the literature because it allows setups to be carried over from one period to another and because it is computationally viable for realistic-sized problems.     

法国现象学或实存与知识的张力

现象学在法国的引进与发展包含了主体哲学和概念哲学的共同努力。在主体哲学和概念哲学之间存在着复杂的关联,这意味着实存论与知识论之间巨大的张力。现象学在20世纪法国哲学中占据着主导地位,但现象学有着复杂多样的形态,出现了从意识现象学到身体现象学再到物质现象学的演变。     

The Performance of MRP Purchase Lot-Size Procedures Under Actual Multiple Purchase Discount Conditions

Several heuristic procedures for purchase lot sizing in material requirements planning (MRP) systems were tested with actual data from manufacturing companies. Information provided by the companies for each purchased item included the estimated requirements and costs, the price discount structure from the vendor, and the actual company ordering policy. Simulation tests for each purchased item involved comparisons of several purchase lot-size procedures from the research literature along with the actual procedure used by the company providing the data. Results indicate that one of the heuristic lot-size procedures from the literature consistently outperformed the company policies as well as all other models tested. Another noteworthy result is that, in some cases, the actual company order policy was more cost-effective than some of the models from the research literature.     

《遗传优生》内容调整刍议

现在使用的《遗传优生》教材,是16年前编写的,内容陈旧,只有经典遗传理论而缺乏对优生实践的指导,不符合我院遗传优生教学大纲的规定,不适应人口与计生专业培养人才的需要。所以,应对《遗传优生》加以调整和充实:把细胞学、遗传学、遗传病及其预防与预测等方面的遗传理论与优生实践紧密结合在一起,并补充性细胞保护、遗传规律、婚配关系等在优生方面的作用以及人类基因组计划等相关知识和最新科研成果,为提高出生人口素质,降低出生缺陷率服务。     

第X方物流理论

基于物流 (MF) [1 ] 的属性和企业发展理论 ,在国内首次提出物流新理论———“第X方物流”(X’sPartyMaterialFlow ,简称XPMF)。认为第X方物流不仅指由某一方提供的物流服务业务模式 ,更重要的是指由各有关方综合提供的物流服务业务模式。物流理论和实践证明 ,企业不可能采用某一种固定的物流服务业务模式 ,采用哪种物流服务业务模式是一个事先不能确定的未知数 ,需要根据具体情况进行科学决策 ,故名第X方物流。第X方物流理论符合物流服务业务模式的发展规律。讨论了第X方物流的概念和其运作性质     

新疆城乡女性人才相关因素比较

主要依据"新疆女性人才资源开发利用研究"课题组问卷调查数据,从新疆城乡女性人才的物质待遇状况,对外在环境的评判和性别意识三个方面,对新疆城乡女性人才发展的相关因素予以揭示和比较。