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Assessment of Fatigue Strength of An Offshore Floating Production and Storage Unit 被引量:1
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作者 LIU Jiancheng(刘建成) +1 位作者 GU Yongning(顾永宁) 《China Ocean Engineering》 SCIE EI 2002年第1期41-49,共9页
The procedure of assessment of structural fatigue strength of an offshore floating production and storage and offloading unit (FPSO) in this paper. The emphasis is placed on the long-term prediction of wave induced lo... The procedure of assessment of structural fatigue strength of an offshore floating production and storage and offloading unit (FPSO) in this paper. The emphasis is placed on the long-term prediction of wave induced loading, the refined finite element model for hot spot stress calculation, the combination of stress components, and fatigue damage assessment based on S-N curve. 展开更多
关键词 offshore structure fatigue strength hot spot stress long-term prediction floating production and storage and offloading unit
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Performance Evaluation for Gas Production Units Based on ANP
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作者 Jianhong Gou Anqi Li +2 位作者 Zhibin Liu Xinhai Kong Haohan Liu 《Engineering(科研)》 2013年第11期877-880,共4页
In view of the existing situation of gas field development, one kind of method to evaluate the production performance of gas production units (GPUs) was presented in this paper. Among the commonly used indicators of g... In view of the existing situation of gas field development, one kind of method to evaluate the production performance of gas production units (GPUs) was presented in this paper. Among the commonly used indicators of gas field development, we select 11 indicators from the three aspects of production task, gas reservoir management, and production technology. According to the principle of analytic network process (ANP), this paper introduced one kind of new method to get the weights of indicators. By means of the method of TOPSIS, it is easy to obtain the rankings for all the GPUs through calculating the weighted Euclidean distance between each GPU and the positive or negative ideal point. This evaluation method could constantly improve the management level of gas production units and deepen the delicacy management of gas field development. 展开更多
关键词 GAS production unit (GPU) Performance Evaluation ANALYTIC Network Process (ANP) TOPSIS
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Name Brand Products of Shanghai Jiahua United Company
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《中国对外贸易》 1995年第7期44-44,共1页
Ruby—the country’s first seriescosmetics The Ruby Beauty Parlor andCosmetics School is the first of its kind inChina. The skin-care and make-upmethods it has applied are still popular.Among the gifts presented to qu... Ruby—the country’s first seriescosmetics The Ruby Beauty Parlor andCosmetics School is the first of its kind inChina. The skin-care and make-upmethods it has applied are still popular.Among the gifts presented to queenElizabeth Ⅱ of Britain, British PrimeMinister Mrs. Thatcher and RussianPresident Gorbachev by the Chinesegovernment, there was Ruby. According to market surveys andthe conclusions of beauty culture, workingwomen in modern society with their fastrhythm of life and exquisite tastes arefastidious in selecting cosmetics. To meettheir special needs, Ruby’s white 展开更多
关键词 Ruby Name Brand products of Shanghai Jiahua united Company
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Assessment of Knowledge,Attitudes and Practices of Food Handlers in Attieke Production Units in Relation to Food Hygiene and Safety in Cote d’Ivoire in 2012
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作者 Theodore N.Djéni Alfred K.Kouamé +2 位作者 Youssouf Traoré Rose K.Nevry Marcellin K.Dje 《Food and Nutrition Sciences》 2014年第10期896-904,共9页
The aims of this study were to investigate the food safety knowledge and practices of food handlers and to assess the sanitary conditions of attieke production units in the South of C?te d’Ivoire. A cross-sectional s... The aims of this study were to investigate the food safety knowledge and practices of food handlers and to assess the sanitary conditions of attieke production units in the South of C?te d’Ivoire. A cross-sectional study was conducted during 4 months in 2012 in 7 localities and data were collected using questionnaire and observation checklist and microbiological analysis of hands. A total of 775 attieke production units were involved in this survey. Seventy-one percent (71%) were located on public domains and only 70 production units (9%) used septic tank as a mean of final deposal for liquid waste. Hygiene conditions and practices of food handlers in attieke production units were inadequate. The presence of specific microorganisms such as Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter youngae, Klebsiella oxytoca and Citrobacter freundi was indicative of a degree of ignorance on the part of food handlers towards proper hygienic practices. 展开更多
关键词 Attieke Food Handlers Hygienic Practices production units
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TECHNOLOGY AND APPLICATION OF PRODUCT EVOLUTIONARY DESIGN BASED ON CONFIGURATION IN MASS CUSTOMIZATION MODE 被引量:3
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作者 FENG Yixiong CHENG Jin +2 位作者 TAN Jianrong ZHENG Bing WEI Zhe 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期113-119,共7页
Product customization has been recognized as an effective means to implement mass cus-tomization (MC). A new theory and method for MC-oriented evolutionary design of configuration product is presented based on the s... Product customization has been recognized as an effective means to implement mass cus-tomization (MC). A new theory and method for MC-oriented evolutionary design of configuration product is presented based on the study of developing law of evolutionary design in integrated envi-ronment, which focuses on the innovation and reuse properties of configuration product. The key technologies for general requirement modeling in quick response to customer requirement, multi-level stepwise configuration optimization driven by customer requirement and evolutionary deduction of product variable structure based on configuration association are thoroughly investigated. The suc-cessful application of the presented method in the development of real-life products demonstrates its utility, flexibility and robusticity. 展开更多
关键词 Mass customization Evolutionary design Configuration product Configuration unit
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Investigation of Internal Turret Mooring System for Oil Production Storage Vessels
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作者 Ma Zhiliang , Huang Xianglu , Ma Peisun Fan Genfa, Yu Xiangsan and Jin Dexian Professor, Shanghai Jiao Tong University, Shanghai Associate Professor, Shanghai Jiao Tong University, Shanghai Research Fellow, Shanghai Jiao Tong University, Shanghai 《China Ocean Engineering》 SCIE EI 1991年第4期395-408,共14页
The internal turret mooring system for oil production storage vessels is a developing type ofoffshore floating production system suitable for deep water and harsh environmental application. In this paper, some achieve... The internal turret mooring system for oil production storage vessels is a developing type ofoffshore floating production system suitable for deep water and harsh environmental application. In this paper, some achievements in our research work are presented. The description includes: dynamic analysis of mooring system, research on performance of turret assembly, influence of vessel dimensions and hull forms on mooring performance, model tests under combined action of environmental forces in basin, and hull structural strength analysis. 展开更多
关键词 floating production system single point mooring turrent mooring system oil production storage vessel production storage unit
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Research on Digital Models for Product Design and Manufacture
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作者 WANG Zhong-qing, GUO Chun-liang (East China Jiaotong University, Nanchang 330013, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期155-156,共2页
CAD/CAM integrate technology has been drawn to much a ttention and becomes one of the focus of the international academic and commerci al research, Through efforts nearly 10 years, remarkable progress has been made in... CAD/CAM integrate technology has been drawn to much a ttention and becomes one of the focus of the international academic and commerci al research, Through efforts nearly 10 years, remarkable progress has been made in the 3-dimension feature parametric modeling. UG, SOLIDWORK and MDT apply the se technology with respective features. However, no distinct development has bee n made in the digital models from geometric feature to manufacture feature. Prod uct information expression and the basic model frame of data exchange have been proposed based on STEP standards, but it is quite difficult to some extent ensur e the operability, due to the complexity in application. The models addressed in this paper divide the shared digital models (not data models) for product desig n and manufacture into five parts: ①Digital product 3D molding design; ②Digit al product technology process design; ③Digital product assembly design; ④Digit al product manufacture process design; ⑤Digital product management design. The resource model should not be included. And It should be a peripheral model i n product design; which is the innovative viewpoint of this paper. The core of above-mentioned five models is to access the digital model from the solid unit feature. Product definition should be determined on the basis of solid unit, and solid unit should follow the rules of "generation of machining processing", Therefore, the author also proposed the Constructing Cutting Geomet ry Method (CCG) in IMCC’2000. In this way, the integration of "forming - processing - assembling - machining - management" can be obtained. This is th e core originality of the paper. 展开更多
关键词 product digitization solid unit technique CAD CAPP CAM
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Report on a breeding objective that may reduce the carbon footprint of extensive cow-calf production systems 被引量:1
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作者 Motshabi Catherine Mokolobate Machiel Matthys Scholtz +1 位作者 Sendros Demeke Mulugeta Frederick Wilhelm Cornelius Neser 《Natural Science》 2013年第1期167-171,共5页
Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned pe... Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned per Large Stock Unit (LSU) can eventually be translated to kilogram calf produced per kg CO2 equivalent. A LSU is defined as a bovine requiring 75 MJ Metabolisable Energy (ME) per day. If more kilogram weaner calf can be produced per LSU (KgC/LSU), the carbon footprint of beef can be reduced. This study used breed average values to investigate the KgC/LSU for the 30 beef and dual purpose breeds in South Africa. The breeds were categorized in the following breed types: Sanga (indigenous to South Africa) Sanga derived, Zebu, Zebu derived, British and European. No relationship was found between cow weights and KgC/LSU, indicating that it is independent of cow weight between breeds. However, when the data is summarized into breed types, the Sanga and European breed types produce the least KgC/ LSU and Sanga derived breed types the most. This high value of the Sanga derived breeds is probably due to retained heterosis. Composite breeds are mostly intermediate to parental breeds for individual traits but superior for composite traits and KgC/LSU is a composite trait. These calculations were only done on breed averages. A genetic analysis on a breed level to estimate genetic parameters for this trait, and its genetic correlations with other traits now needs to be done before a decision can be taken whether selection for KgC/LSU will be feasible. The ultimate aim with a trait like this is to reduce the carbon footprint of weaner calf production since more kilogram calf will be produced per LSU (constant feed unit). 展开更多
关键词 BEEF production Breeding CATTLE Large STOCK unit Sanga Weaner CALF Component
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乌兰煤生物产气过程中大分子结构的变化特征 被引量:1
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作者 夏大平 秦旭 +4 位作者 邓泽 石尚威 李银川 薛培 张亚伟 《煤炭转化》 北大核心 2025年第1期55-66,共12页
为阐明煤的大分子结构特征及其在生物产气过程中的变化,选择内蒙古锡林郭勒盟乌兰图噶矿区的褐煤进行生物产气实验,通过^(13)C-NMR测试、元素分析、X射线光电子能谱测试研究其结构变化特征。结果表明:原始乌兰煤样的芳香结构基本单元由... 为阐明煤的大分子结构特征及其在生物产气过程中的变化,选择内蒙古锡林郭勒盟乌兰图噶矿区的褐煤进行生物产气实验,通过^(13)C-NMR测试、元素分析、X射线光电子能谱测试研究其结构变化特征。结果表明:原始乌兰煤样的芳香结构基本单元由3个苯环、3个萘环、1个蒽环和3个吡咯组成,碳原子总数为129个。经过微生物的生物产气作用,碳原子总数减少了21个,其中芳香族碳减少了4个,脂肪族碳减少了17个。原始乌兰煤样大分子结构中的脂肪碳原子为55个,生物产气结束后,脂肪碳数量减少了21.8%,亚甲基碳数量减少了25%,次甲基碳和季碳数量减少了16.7%,氧接脂碳和甲基碳数量分别减少了14.3%和33.3%。煤大分子的芳香结构基本单元和侧链脱落主要发生在水解阶段,在后期产甲烷阶段,煤的结构改造基本停止,仅依靠已脱落于反应液中的物质参与生化反应,这证实了在生物产气过程中,煤大分子结构向更高芳构化程度转化是一个显著的趋势。 展开更多
关键词 大分子结构 褐煤 生物产气 芳香结构基本单元 脂肪碳
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Flush by Unit在哥伦比亚Capella油田的应用
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作者 黎红胜 温慧芸 +1 位作者 郑振国 李陶涛 《地质装备》 2023年第1期40-43,共4页
Capella油田是哥伦比亚南部重要的稠油油田,目前处于开发生产阶段,为了油田的稳产增产,需频繁对油井进行干预。Flush by Unit具有操作简单、移动高效、作业时间缩短、安全事故少等优点,作为试点引入了Flush by Unit为该油田的浅井提供... Capella油田是哥伦比亚南部重要的稠油油田,目前处于开发生产阶段,为了油田的稳产增产,需频繁对油井进行干预。Flush by Unit具有操作简单、移动高效、作业时间缩短、安全事故少等优点,作为试点引入了Flush by Unit为该油田的浅井提供修井服务,以降低桶油成本。本文介绍了Flush by Unit的结构组成、使用范围、现场使用效果,与传统修井机相比,可以大幅降低作业时间和成本,为后续规模使用Flush by Unit进行常规修井提供了依据,也为油田的增产稳产带来了机遇。 展开更多
关键词 Flush by unit 修井 增产稳产
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Development unit division and favorable area evaluation for joint mining coalbed methane 被引量:6
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作者 YANG Zhaobiao LI Yangyang +6 位作者 QIN Yong SUN Hansen ZHANG Ping ZHANG Zhengguang WU Congcong LI Cunlei CHEN Changxiao 《Petroleum Exploration and Development》 2019年第3期583-593,共11页
Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step metho... Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step method” of optimal combination of production layers is corrected, and then the CBM production layer potential index is introduced to evaluate favorable areas for commingled multi-coal seam production. Through analysis of the key parameters of coal reservoirs affecting the CBM productivity index, a development unit division method for areas with multi-coal seams is established, and a quantitative grading index system is proposed. On this basis, the evaluation process of CBM development favorable area is developed: the mature 3-D modeling technology is used to characterize the reservoir physical properties of multi-coal seams in full-scale;the production layer potential index of each grid is calculated, and the production layer potential index contour under single-layer or commingled multi-layer production are plotted;according to the distribution of the contour of production layer potential index, the quantitative index of CBM development unit is adopted to outline the grade I, II, III coal reservoir distribution areas, and thus to pick out the favorable development areas. The practical application in the Yuwang block of Laochang in Yunnan proved that the favorable area evaluation process proposed can effectively overcome the defects of selecting favorable development areas only relying on evaluation results of a major coal seam pay, and enhance the accuracy of the evaluation results, meeting the requirements of selecting favorable areas for multi-coal seam commingled CBM production. 展开更多
关键词 coalbed methane reservoir physical property JOINT MINING production layer potential INDEX DEVELOPMENT unit DIVISION quantitative INDEX favorable area EVALUATION
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Optimizing Factory Performance for Unit Cost in Semiconductor Manufacturing
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作者 Adar A. Kalir 《Open Journal of Optimization》 2023年第2期61-71,共11页
The integrated circuit (IC) manufacturing process is capital intensive and complex. The production process of unit product (or die, as it is commonly referred to) takes several weeks. Semiconductor factories (fabs) co... The integrated circuit (IC) manufacturing process is capital intensive and complex. The production process of unit product (or die, as it is commonly referred to) takes several weeks. Semiconductor factories (fabs) continuously attempt to improve their productivity, as measured in output and cycle time (or mean flow time). The conflicting objective of producing maximum units at minimal production cycle time and at the highest quality, as measured by die yield, is discussed in this paper. The inter-related effects are characterized, and a model is proposed to address this multi-objective function. We then show that, with this model, die cost can be optimized for any given operating conditions of a fab. A numerical example is provided to illustrate the practicality of the model and the proposed optimization method. 展开更多
关键词 Semiconductor Manufacturing Cycle Time Die Cost unit Cost YIELD Optimization productIVITY
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基于PAM-GRU的三苯收率预测方法研究及应用
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作者 韩永明 孙亚帅 +5 位作者 倪庆旭 潘峰 孙庆峰 谭蕾 胡渲 耿志强 《过程工程学报》 北大核心 2025年第10期1030-1038,共9页
针对传统三苯收率预测中存在的模型精度低的问题,本工作提出了一种基于金字塔注意力机制的门控循环单元网络(PAM-GRU)的三苯收率预测方法。PAM-GRU通过引入金字塔注意力机制,利用卷积对多特征序列数据建立层次化的注意力结构,解决传统... 针对传统三苯收率预测中存在的模型精度低的问题,本工作提出了一种基于金字塔注意力机制的门控循环单元网络(PAM-GRU)的三苯收率预测方法。PAM-GRU通过引入金字塔注意力机制,利用卷积对多特征序列数据建立层次化的注意力结构,解决传统自注意力机制性能增益受限问题,以提取空间特征。同时引入门控循环单元,利用其循环结构捕捉时间序列中的动态信息,挖掘时序数据的时间变化规律。通过融合数据的时空特征,实现对三苯收率的准确预测。所提方法应用在实际连续重整化工生产流程中,在平均绝对百分比误差、平均方根误差、平均绝对误差、决定系数四个指标上与循环神经网络、长短期记忆网络、门控循环单元、基于注意力机制的长短期记忆网络、基于注意力机制的门控循环单元模型对比。结果表明,所提出的PAM-GRU模型能够有效整合连续重整生产过程中的空间和时间特征,实现对三苯收率的高效、准确预测。此外,为应对复杂生产环境,对模型增加了鲁棒性测试,结果表明,所提模型具有较强的鲁棒性,能够有效抑制突发噪声的干扰。 展开更多
关键词 金字塔注意力机制 门控循环单元 化工生产 三苯收率预测
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中国南海北部湾边际油田可移动平台可行性研究
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作者 刘涛 《海洋工程装备与技术》 2025年第2期127-131,共5页
针对南海北部区域距离在生产油田较近、储量较小、开发年限较短的小型或边际油气田的经济有效开发难题,提出采用可移动平台进行开发的模式,可以有效降低开发成本实现油田的经济开发,同时为类似油田的开发提供指导。
关键词 边际油田 经济有效开发 可移动平台可行性研究
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基于AGV智能调度算法的航空物流虚拟制造系统驱动研究 被引量:1
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作者 王吉寅 《自动化与仪器仪表》 2025年第8期176-179,共4页
完善的物流控制系统是航空产品安全生产的前提,因此,研究提出改进非支配排序遗传算法第二版和基于自动导引运输车智能调度算法的航空物流虚拟制造系统,最后进行实验验证。实验结果表明研究提出的算法在收敛前后的平均利用率分别为38.64%... 完善的物流控制系统是航空产品安全生产的前提,因此,研究提出改进非支配排序遗传算法第二版和基于自动导引运输车智能调度算法的航空物流虚拟制造系统,最后进行实验验证。实验结果表明研究提出的算法在收敛前后的平均利用率分别为38.64%和95.27%,比传统算法分别高出5.66%和7.34%。并且算法控制下的平均等待时间及绝对偏差分别为18.93 s和1.79 s,比传统算法分别低7.31 s和0.96 s。此外,研究提出的系统的实际利用率及等待时间分别为91.45%和24.74 s,而其他系统则分别为83.82%和32.87 s。并且系统的平均调度冲突次数及绝对偏差分别为4.73次和1.26;此时其他系统则为9.32次和1.67。综上所述,研究提出的系统显著提高了车间物流效率。研究能够优化航天产品生产的调度策略,推动航天产业安全稳定发展。 展开更多
关键词 航空产品 NSGAII 虚拟制造单元 数字孪生模型 物流调度 鲁棒评价
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基于绿电转氨的综合能源生产单元经济性与碳足迹评估 被引量:4
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作者 孙立 余潜跃 +2 位作者 张玉琼 赵强 郝勇生 《中国电机工程学报》 北大核心 2025年第7期2567-2578,I0010,共13页
基于电转氨(power to ammonia,P2A)的综合能源生产单元(integrated energy production unit,IEPU)通过耦合绿电制氢和哈伯反应合成氨工艺,为农业、工业和制造业等行业提供绿氨,对促进可再生能源消纳及氢能储运等行业发展具有重要的意义... 基于电转氨(power to ammonia,P2A)的综合能源生产单元(integrated energy production unit,IEPU)通过耦合绿电制氢和哈伯反应合成氨工艺,为农业、工业和制造业等行业提供绿氨,对促进可再生能源消纳及氢能储运等行业发展具有重要的意义。为定量评价IEPU的能效、技术经济性和降碳潜力,该文基于Aspen Plus建立碱性电解水制氢、合成氨及换热网络等关键过程模型,对IEPU进行系统仿真,定量评价各设备全流程之间的能量流、(火用)流、碳足迹及绿氨的平准化成本。热经济性能效评估表明,IEPU系统的设计工况整体能量效率为39.47%,(火用)效率为26.51%。技术经济性评估表明,当可再生能源电价为0.204元/(kW·h),年利用小时数达到6000时,IEPU系统的绿氨成本约为传统煤制氨生产工艺的1.5倍。基于全生命周期碳足迹评价的结果表明,水、核、风和光伏4种能源驱动的IEPU系统碳足迹在0.20~2.39 kg CO_(2.eq)/kg NH3间波动。结果可用于指导氨基IEPU的规划与设计。 展开更多
关键词 电转氨 综合能源生产单元 能效分析 技术经济性评估 全生命周期评估
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海外产品分成制合同新增投资单元效益特点及财税红利分析--以非洲某国家A区块为例
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作者 张礼貌 陈焕杰 《当代石油石化》 2025年第5期40-47,共8页
海外油气项目由于其相对特殊的财税条款设计,尤其是产品分成制合同,其新增投资单元效益需根据区块整体效益变化来衡量。以非洲某国家A区块为例,采用增量法,分析产品分成制合同新增投资单元的效益变化特点,发现新井效益并不总随油价增长... 海外油气项目由于其相对特殊的财税条款设计,尤其是产品分成制合同,其新增投资单元效益需根据区块整体效益变化来衡量。以非洲某国家A区块为例,采用增量法,分析产品分成制合同新增投资单元的效益变化特点,发现新井效益并不总随油价增长而正向增加,少部分情形下新井产量降低,效益反而增加,新井单元实施顺序不同会导致效益有较大差异等。另外,A区块由于特殊的利润油分成机制,存在明显财税红利,即新井产量很低的情形下也能产生正向现金流。针对这些特点,对海外产品分成制合同项目新增投资单元投资决策和发展提出3点建议:一是新井效益评价应采用增量法,二是加大新增投资单元效益变化特点分析,三是提高新井单井经济极限可采储量在新井投资决策中的应用,重点分析财税红利。 展开更多
关键词 海外油气项目 产品分成制 新增单元效益 财税红利
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城乡融合发展中的空间治理 被引量:1
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作者 吴宇哲 《人民论坛·学术前沿》 北大核心 2025年第7期93-100,共8页
城乡融合发展是基于新型城镇化和乡村全面振兴的统筹,城乡融合发展中的空间治理导向是高质量发展,旨在实现生产空间高效、生活空间包容、生态空间绿色。生产空间治理要使优势地区有更大的发展空间,同时为农村地区实现粮食安全提供保障,... 城乡融合发展是基于新型城镇化和乡村全面振兴的统筹,城乡融合发展中的空间治理导向是高质量发展,旨在实现生产空间高效、生活空间包容、生态空间绿色。生产空间治理要使优势地区有更大的发展空间,同时为农村地区实现粮食安全提供保障,通过以工补农、以城带乡实现城乡共同富裕;生活空间治理的重点是改善城乡交通,在城市加大保障性住房的建设与供给,从而实现农业转移人口市民化,进而撬动农村土地制度改革;生态空间治理的核心是生态价值实现,在大城市郊区或县城提供改善型住房,并开展农村特色生态旅游、打造国家公园区域公共生态品牌产品体系,实现“绿水青山就是金山银山”。 展开更多
关键词 新型城镇化 乡村全面振兴 生产空间 生活空间 生态空间 县域
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Models for Ordering Multiple Products Subject to Multiple Constraints, Quantity and Freight Discounts
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作者 John Moussourakis Cengiz Haksever 《American Journal of Operations Research》 2013年第6期521-535,共15页
One of the most important responsibilities of a supply chain manager is to decide “how much” (or “many”) of inventory items to order and how to transport them. This paper presents four mixed-integer linear program... One of the most important responsibilities of a supply chain manager is to decide “how much” (or “many”) of inventory items to order and how to transport them. This paper presents four mixed-integer linear programming models to help supply chain managers make these decisions for multiple products subject to multiple constraints when suppliers offer quantity discounts and shippers offer freight discounts. Each model deals with one of the possible combinations of all-units, incremental quantity discounts, all-weight and incremental freight discounts. The models are based on a piecewise linear approximation of the number of orders function. They allow any number of linear constraints and determine if independent or common (fixed) cycle ordering has a lower total cost. Results of computational experiments on an example problem are also presented. 展开更多
关键词 INVENTORY MIXED-INTEGER Linear Programming Quantity and FREIGHT Discounts All-units and INCREMENTAL Discounts MULTIPLE products and MULTIPLE Constraints
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中国夏奥征程40年的历史回顾、未解难题与前瞻思考
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作者 谭广鑫 刘露 段锐 《上海体育大学学报》 北大核心 2025年第6期38-49,共12页
夏季奥运会表现是衡量体育强国建设成效的重要指标。运用文献研究法、访谈法和逻辑分析法,对我国夏奥征程40年来的成就、经验与未解难题进行分析。认为,基于党的领导和奥运战略、新型举国体制的支持,我国在回应历史之问、拓展参赛版图... 夏季奥运会表现是衡量体育强国建设成效的重要指标。运用文献研究法、访谈法和逻辑分析法,对我国夏奥征程40年来的成就、经验与未解难题进行分析。认为,基于党的领导和奥运战略、新型举国体制的支持,我国在回应历史之问、拓展参赛版图、提升竞技成绩、收敛中美竞技体育差距、构筑中华体育精神、加强对外体育文化交流方面取得显著成效。我国参与夏季奥运会仍面临项目发展“不平衡、不充分”的困境,表现为我国夏奥项目整体发展不平衡,集体球类项目、基础大项和潜优势项目发展不充分。未来应坚持守正创新,完善以新型举国体制为基础的多轨并存新机制;抢占科技制高点,创造以新质生产力为支撑的竞技体育发展新优势;注重夯基固本,优化以体教融合为重心的多元人才培养体系;践行全面求强,推行以“量的合理增长”与“质的有效提升”为主线的发展战略。 展开更多
关键词 奥运会 竞技体育 中美 新质生产力 高质量发展 体育强国
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