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Energy Demand Growth Rate to Slow Down
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《Journal of Natural Gas Chemistry》 CAS CSCD 2004年第4期249-250,共2页
China’s energy demand growth rate is expected to slow down next year, with the government’s efforts to curb energy consumption intensive industries taking effect, executives from State oil and power companies said y... China’s energy demand growth rate is expected to slow down next year, with the government’s efforts to curb energy consumption intensive industries taking effect, executives from State oil and power companies said yesterday. Refined oil product consumption in China is likely 展开更多
关键词 CNPC DOWN Energy demand Growth rate to Slow Down
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TRANSFORM THE MECHANISM OF RENMINBI’S EXCHANGE RATE SYSTEM IN CONFORMITY WITH THE DEMAND OF MARKET ECONOMY——The academic report delivered at the Annual Meeting of NNCIFS on October 1993
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作者 Qian Rongkun NANKAI UNIVERSITY.Cui Yonglu 《南开经济研究》 CSSCI 北大核心 1994年第S1期2-11,共10页
Exchange rate functions under systems of centrallyplanned economy and market economy are quite different,and the mechanism to determine such exchange rate is alsodifferent. To adopt a socialist market economic system ... Exchange rate functions under systems of centrallyplanned economy and market economy are quite different,and the mechanism to determine such exchange rate is alsodifferent. To adopt a socialist market economic system inChina, the exchange rate mechanism of Renminbi must bethoroughly transformed. To accomplish this goal, I believethere are three problems that must be solved: first, 展开更多
关键词 rate TRANSFORM THE MECHANISM OF RENMINBI The academic report delivered at the Annual Meeting of NNCIFS on October 1993 S EXCHANGE rate SYSTEM IN CONFORMITY WITH THE demand OF MARKET ECONOMY
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A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite
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作者 Mohammad Ekramol Islam Shirajul Islam Ukil Md. Sharif Uddin 《Open Journal of Applied Sciences》 2016年第1期38-48,共11页
In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considerin... In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example. 展开更多
关键词 Production Inventory Shelf-Life Time Dependent demand Class Production rate
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An Optimal Policy with Quadratic Demand, Three-Parameter Weibull Distribution Deterioration Rate, Shortages and Salvage Value
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作者 Pandit Jagatananda Mishra Trailokyanath Singh Hadibandhu Pattanayak 《American Journal of Computational Mathematics》 2016年第3期200-211,共12页
The present paper focuses an optimal policy of an inventory model for deteriorating items with generalized demand rate and deterioration rate. Shortages are allowed and partially backlogged. The salvage value is inclu... The present paper focuses an optimal policy of an inventory model for deteriorating items with generalized demand rate and deterioration rate. Shortages are allowed and partially backlogged. The salvage value is included into deteriorated units. The main objective of the model is to minimize the total cost by optimizing the value of the shortage point, cycle length and order quantity. A numerical example is carried out to illustrate the model and sensitivity analyses of major parameters are discussed. 展开更多
关键词 EOQ Quadratic demand Salvage Value SHORTAGE Three-Parameter Weibull Deterioration rate
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低出生率背景下省域学前教育资源供需关系与动态调配——基于对中部J省人口预测的分析
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作者 冯婉桢 袁一清 伍津 《学前教育研究》 北大核心 2024年第5期45-57,共13页
低出生率背景下研判省域学前教育资源供需关系的变化,对优化学前教育资源配置、实现学前教育优质均衡发展具有指导意义。本研究选择省域学前教育资源配置中低供给高需求类型的中部J省作为研究对象,运用PADIS-INT软件预测分析了J省2023—... 低出生率背景下研判省域学前教育资源供需关系的变化,对优化学前教育资源配置、实现学前教育优质均衡发展具有指导意义。本研究选择省域学前教育资源配置中低供给高需求类型的中部J省作为研究对象,运用PADIS-INT软件预测分析了J省2023—2035年低、中、高三种方案下城乡在园幼儿人数的变化,调查了J省学前教育人力资源与物力资源供给现状,进而预测分析了J省学前教育资源在供给动态变化与静态不变情况下的供需关系。结果发现,随着在园幼儿人数减少,学前教育资源需求将明显减少;现有人力资源供给存在结构性短缺,未来会出现城乡配置失衡;物力资源配备已达到高水平,未来会严重过剩。根据研究结果,建议地方政府根据资源供需关系的动态变化做好学前教育长期规划,控增量、调存量、疏余量;从结构与质量入手优化人力资源配置,稳定乡村教师队伍;谨慎增加办园条件投入,采用多种形式提升物力资源使用效益。 展开更多
关键词 学前教育资源 供需关系 低出生率 动态调配
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云储能模式下分布式用户虚拟储能需求评估
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作者 王云鹏 胡健 +2 位作者 张晓杰 冀瑞强 齐晓妹 《可再生能源》 CAS CSCD 北大核心 2024年第5期694-703,共10页
采用分布式储能技术可以改变能量的时空分布,提高配电网消纳分布式能源的灵活性。传统储能模式下储能成本过高、储能资源利用率低,而云储能是一种能够响应分布式储能需求的新型商业模式。文章考虑负荷、可再生能源出力、分时电价以及虚... 采用分布式储能技术可以改变能量的时空分布,提高配电网消纳分布式能源的灵活性。传统储能模式下储能成本过高、储能资源利用率低,而云储能是一种能够响应分布式储能需求的新型商业模式。文章考虑负荷、可再生能源出力、分时电价以及虚拟储能价格等影响用户虚拟储能需求的因素,建立了云储能模式下分布式用户虚拟储能需求配置优化模型。为验证该模型的有效性,选取社区内14个典型用户为分析对象。算例分析表明,与传统储能模式相比,云储能模式下用户的虚拟储能容量及功率需求分别降低了18.2%和7.1%,年化成本降低了4.12%,储能资源利用率提升了8.12%。因此,云储能模式具有很好的应用前景。 展开更多
关键词 储能 云模式 虚拟储能需求 年化成本 利用率
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新能源消纳与用户侧响应主从博弈的配电网智能软开关选址策略
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作者 陈骁龙 孙嘉 +2 位作者 张俊林 倪良华 吕干云 《电力自动化设备》 EI CSCD 北大核心 2024年第2期57-63,共7页
分布式电源接入配电网后,配电网调控能力不足导致新能源消纳水平低、用户支出经济性指标差,提出一种新能源就地消纳和用户支出主从博弈的配电网智能软开关选址策略的嵌套模型和方法。外层建立以新能源渗透率最大、电能质量指标最佳且计... 分布式电源接入配电网后,配电网调控能力不足导致新能源消纳水平低、用户支出经济性指标差,提出一种新能源就地消纳和用户支出主从博弈的配电网智能软开关选址策略的嵌套模型和方法。外层建立以新能源渗透率最大、电能质量指标最佳且计及传统调控手段的模型结构;内层考虑新能源用户消纳的分时电价、储能装置充放电成本和日运行费用因素,构建能满足用户支出成本最低的需求响应模型。调用CPLEX求解器求解混合整数非线性规划模型,用户侧与配电网侧模型通过反复博弈优化决策变量,主从博弈内层优化采用改进粒子群优化算法加快收敛速度。以改进的IEEE 33节点系统为算例进行分析,验证了所提智能软开关选址策略的有效性。 展开更多
关键词 主从博弈 智能软开关选址策略 新能源渗透率 需求响应 新能源消纳
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考虑供需匹配特性的冷热电联供系统运行策略研究
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作者 李要红 王鹏翔 +1 位作者 彭斌 姚鑫 《电力系统保护与控制》 EI CSCD 北大核心 2024年第11期52-62,共11页
针对以电定热和以热定电运行策略能量冗余以及混合热电运行策略能源不足的特性,在热电负荷平衡运行策略的基础上,提出了改进的热电负荷平衡运行策略。以北方某酒店为研究对象,并以最大化能源利用率为目标对系统的装机容量进行了优化,同... 针对以电定热和以热定电运行策略能量冗余以及混合热电运行策略能源不足的特性,在热电负荷平衡运行策略的基础上,提出了改进的热电负荷平衡运行策略。以北方某酒店为研究对象,并以最大化能源利用率为目标对系统的装机容量进行了优化,同时提出了能源综合指数,研究了在5种运行策略下购买能量和冗余能量对系统性能的影响。然后分析了在不同运行策略下系统的供需匹配特性和改进的热电负荷平衡策略下系统的能量平衡关系。最后,通过算例探究了改进的热电负荷平衡策略对提高系统经济性的作用,并经过对比分析验证了研究的合理性与有效性。研究结果表明,与其他4种运行策略相比,改进的热电负荷平衡运行策略下系统的能源利用率分别提高了4.3%、4.38%、4.75%、4.73%;能源综合指数分别降低了6.58%、5.96%、2.23%、3.45%;系统的年总成本分别降低了11.65%、2.74%、1.64%、0.74%。其中,改进的热电负荷平衡策略下系统的供需匹配性能最优(为0.9382)。 展开更多
关键词 运行策略 能源利用率 能源综合指数 供需匹配
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考虑故障率和修复次数的装备可修部件需求预计方法
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作者 吴巍屹 李贵茹 +1 位作者 赵张鹏 黄巍 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第S01期166-169,202,共5页
针对装备可修部件的消耗预测粗放、困难、不准确,考虑可修部件故障率回退概率和修复次数约束限制,运用可靠性分析及随机过程理论,构建可修部件需求数量预计方法,通过算例分析说明,该预计方法比不考虑部件故障率回退的装备可修部件需求... 针对装备可修部件的消耗预测粗放、困难、不准确,考虑可修部件故障率回退概率和修复次数约束限制,运用可靠性分析及随机过程理论,构建可修部件需求数量预计方法,通过算例分析说明,该预计方法比不考虑部件故障率回退的装备可修部件需求预计方法更为科学合理,证明了该预计方法的科学性和有效性,能够为保障部门确定合理的可修部件筹措、配置和供应数量提供参考。 展开更多
关键词 需求预计 故障率 修复 可修部件
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养老机构入住率的多元供求驱动机制研究——基于NCA和fsQCA的双重分析
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作者 王利娟 伍度志 +2 位作者 刘成杰 吴燕 王路云 《社会保障研究》 北大核心 2024年第2期39-52,共14页
入住率是反映养老机构服务品质、养老服务资源利用效率的重要指标。运用必要条件分析方法和模糊集定性比较分析方法,探究重庆市38个区县养老机构入住率形成的多元供求驱动机制,结果显示:在入住率普遍偏低的背景下,不同地区养老机构入住... 入住率是反映养老机构服务品质、养老服务资源利用效率的重要指标。运用必要条件分析方法和模糊集定性比较分析方法,探究重庆市38个区县养老机构入住率形成的多元供求驱动机制,结果显示:在入住率普遍偏低的背景下,不同地区养老机构入住率的形成机制不同,可将其归纳为以失能老人为核心的机构养老服务需求与综合照料服务供给协同形成的“传统型”高配供求驱动机制,以及以高水平养老资本为保障的机构养老服务需求与高水平医疗保健服务供给协同形成的“医养型”高配供求驱动机制,且后者更有可能产生高入住率。基于此,建议提高机构人员配比,逐步提升养老机构医养融合服务的供给能力,增强老年人的机构养老意愿,以及提升其机构养老服务购买能力。 展开更多
关键词 养老机构 入住率 供求驱动 必要条件分析 模糊集定性分析
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海拔对生活污水处理厂生化池曝气量影响探讨
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作者 南彦刚 《广东化工》 CAS 2024年第5期119-121,共3页
我国地域广阔,平均海拔跨度大,海拔越高氧气越稀薄、气压越低,对污水处理厂标准传氧速率和曝气量具有明显影响。本文结合相关工程实例,对0、500、1000、1500、2000、2500、3000、3500、4000、4500、5000 m海拔下生化池实际需氧量、标准... 我国地域广阔,平均海拔跨度大,海拔越高氧气越稀薄、气压越低,对污水处理厂标准传氧速率和曝气量具有明显影响。本文结合相关工程实例,对0、500、1000、1500、2000、2500、3000、3500、4000、4500、5000 m海拔下生化池实际需氧量、标准传氧速率和曝气量相关参数进行计算和校核。结果表明,考虑氧分压修正工况下曝气量与未考虑修正工况下差值随着海拔增加逐渐增大;实际需氧量不受海拔影响;标准传氧速率、供气量与海拔呈现一定指数关系,高海拔地区标准传氧速率和曝气量成倍增长,与平原地区差距显著。该研究结果也可为相关高原地区生化池曝气量的计算和设备选型提供参考。 展开更多
关键词 生活污水处理厂 海拔 需氧量 标准传氧速率 曝气量
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外部市场需求规模对企业出口国内附加值率的影响研究——基于企业生命周期视角
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作者 佟家栋 赵思佳 张俊美 《山东大学学报(哲学社会科学版)》 北大核心 2024年第1期93-107,共15页
企业作为贸易活动的主体,详细考察外部市场需求规模对企业出口国内附加值率的影响有助于更好地理解国际市场需求环境变化会如何影响企业出口贸易水平。基于理论层面的分析和相应研究假说,以2000—2013年中国工业出口企业为样本数据,探... 企业作为贸易活动的主体,详细考察外部市场需求规模对企业出口国内附加值率的影响有助于更好地理解国际市场需求环境变化会如何影响企业出口贸易水平。基于理论层面的分析和相应研究假说,以2000—2013年中国工业出口企业为样本数据,探讨外部市场需求规模变化对企业出口国内附加值率的影响和作用机制,并着重从企业生命周期异质性视角对该影响与机制进行详细研究发现:外部市场需求增加能够提升企业出口国内附加值率,机制检验表明出口规模效应的促进作用占主导,缓解了竞争效应的抑制作用;由于这两种效应对不同生命周期阶段企业出口国内附加值率的影响存在差异,进而外部市场需求冲击对企业出口国内附加值率的提升作用程度依次为成熟期企业、成长期企业、衰退期企业,这个结论在一系列稳健性检验下依然成立;同时,外部市场需求增加对低技术、加工贸易以及出口到发达国家或地区的企业的出口国内附加值率会产生更明显的积极影响。 展开更多
关键词 外部市场需求规模 企业生命周期 出口规模效应 竞争效应 出口国内附加值率
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践行“征信为民”理念助力龙江经济发展——访中国人民银行黑龙江省分行党委委员、副行长赵庆德
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作者 本刊编辑部 韩丹 焦恒 《征信》 北大核心 2024年第1期13-18,共6页
近年来,中国人民银行黑龙江省分行深入践行“征信为民”服务理念,助力龙江经济发展。一是不断优化征信服务工作管理流程,多渠道满足群众征信服务需求;二是持续探索征信助农模式和路径,促进金融更好服务“三农”经济发展;三是推动动产融... 近年来,中国人民银行黑龙江省分行深入践行“征信为民”服务理念,助力龙江经济发展。一是不断优化征信服务工作管理流程,多渠道满足群众征信服务需求;二是持续探索征信助农模式和路径,促进金融更好服务“三农”经济发展;三是推动动产融资统一登记公示系统和中征应收账款融资服务平台的应用,助力黑龙江省动产融资业务取得积极进展;四是全力推动黑龙江省征信体系建设,积极推动筹建黑龙江省级地方征信平台;五是不断强化对辖内金融信用信息基础数据库接入机构征信业务行为的监督管理,从严履行监管职责;六是积极推进央行内部(企业)评级工作,拓宽金融机构再贷款渠道;七是持续加大征信宣传力度,不断拓展征信宣传的广度和深度。 展开更多
关键词 征信需求 动产融资 征信体系 地方征信平台 征信监管 央行内部(企业)评级 征信宣传
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科研建筑电力负荷密度研究
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作者 张晋波 钱澄清 +1 位作者 于思淼 韩建磊 《建筑电气》 2024年第5期51-56,共6页
通过对中国科学院科研院所集中的北京市中关村和奥运村区域内数十家单位的电力负荷进行深入调查研究,结合有关单位运行维护的电力监测平台数据,通过数据统计、处理和分析,设计流程复盘、设计参数验算等方法,辅以科研院所实地走访等手段... 通过对中国科学院科研院所集中的北京市中关村和奥运村区域内数十家单位的电力负荷进行深入调查研究,结合有关单位运行维护的电力监测平台数据,通过数据统计、处理和分析,设计流程复盘、设计参数验算等方法,辅以科研院所实地走访等手段,从建设单位和设计单位共同关注的科研建筑“怎么算负荷,装机装多大”入手,针对科研建筑电力负荷密度的合理取值作出探索。 展开更多
关键词 科研建筑 节能减碳 电力负荷 峰值负荷密度 装机负荷密度 需要系数 负荷构成 负载率
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An Ordering Policy for Deteriorating Items with Time-Dependent Quadratic Demand and Salvage Value under Permissible Delay in Payment 被引量:1
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作者 Trailokyanath Singh Madan Mohan Muduly +2 位作者 Chittaranjan Mallick Rahul Kumar Gupta Hadibandhu Pattanayak 《American Journal of Operations Research》 2019年第5期201-218,共18页
The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in th... The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided. 展开更多
关键词 Constant Deterioration rate Deteriorating Items Economic Order Quantity Permissible Delay in PAYMENT SALVAGE Value TIME-DEPENDENT QUADRATIC demand rate
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THE APPLICATION RESEARCH OF VIDEO SERVER SYSTEM FOR VIDEO ON DEMAND 被引量:1
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作者 Zhang Yinghui Tao Ran Wang Yue Zhou Siyong 《Journal of Electronics(China)》 2006年第2期295-297,共3页
A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constan... A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constant Bit Rate (VBR/CBR) MPEG-2 MP@ML Signal Program Transport Stream (SPTS) for movies, and general architecture for storage, control, caching subsystems from Loosely Coupled Computer (LCC), Symmetric Multiple Processing (SMP), and Massively Parallel Processing (MPP) video server is conceptualized. Meanwhile, Redundant Array of Inexpensive Disks (RAID) storage system are presented and the centralized FCP/SAN huge storage technology is introduced in terms of its scalability, throughput, and connectivity performances. 展开更多
关键词 视频服务 视频点播 MPEG-2 信号传输
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Research on Sales Strategy Based on Supermarket Pipeline Data
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作者 Shaoyong Hong Chun Yang Hongwei Wen 《Journal of Data Analysis and Information Processing》 2020年第3期99-109,共11页
“Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, ... “Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, but when the goods are lack of flexibility, price reduction will reduce the total revenue. In this paper, according to the sales data provided by a supermarket, we preprocess the data, establish appropriate indicators to measure the daily discount strength of the mall, and establish a mathematical model between the discount strength, sales and profit margin. Through these models, we found that meager profits do bring up sales, but too low discounts can also hurt total profits. In addition, when shopping malls implement discount promotions, they will also bring some negative effects, and we give some suggestions for this. 展开更多
关键词 Low Profit and High Sales Profit Margin Discount rate Price Elasticity of demand
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An Inventory Model of Production with Level Dependent Demand Allowing Few Defective Items
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作者 Md. Jamil Uddin Shirajul Islam Ukil +1 位作者 Aminur Rahman Khan Md. Sharif Uddin 《American Journal of Operations Research》 2021年第1期1-14,共14页
This paper considers a model regarding the products with finite life which allows defective items in reproduction and causes a small amount of decay. The market demand is assumed to be level dependent linear type. The... This paper considers a model regarding the products with finite life which allows defective items in reproduction and causes a small amount of decay. The market demand is assumed to be level dependent linear type. The model has also considered the constant production rate which stops after a desired level of inventories and that is the highest level of it. Due to the market demand, defective item and product’s decay, the inventory reduces to the zero level where again the production cycle starts. With a numerical search procedure</span><span style="font-size:12px;font-family:Verdana;">,</span><span style="font-size:12px;font-family:Verdana;"> the proof of the proposed model has been shown. The objective of the proposed model is to find out the total optimum inventory cost, optimum ordering cost and optimum ordering cycle. 展开更多
关键词 Production Inventory Linear demand Defective Item and Constant Production rate
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Fuzzy Inventory Model with Variable Production and Selling Price Dependent Demand under Inflation for Deteriorating Items
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作者 Tanzim Shahabuddin Shaikh Santosh P. Gite 《American Journal of Operations Research》 2022年第6期233-249,共17页
The main purpose of this paper is to develop an inventory model under fuzzy approach by considering the effect of inflation and time value of money, to determine the optimal time period for inventory cycle and minimum... The main purpose of this paper is to develop an inventory model under fuzzy approach by considering the effect of inflation and time value of money, to determine the optimal time period for inventory cycle and minimum total average costs. The model is integrated production inventory model developed where;the Demand has a direct linear impact on production rate. The model can be divided into four stages. In the first two stages with original production rate and subsequent change in production rate, inventory level rises. Third stage is time after the accumulation of inventory and before the deterioration starts, where demand which selling price dependent is depreciating the inventory level, while in the fourth stage deterioration occurs, which is considered to follow two parameter Weibull distribution. The back-order is not considered. Hexagonal fuzzy numbers are used to derive optimum solution and defuzzification by graded mean integration representation method. A numerical example is given to demonstrate the applicability of the purposed model and sensitivity analysis is carried out to reveal the impact of change in parameter values. 展开更多
关键词 Weibull Distribution Deterioration Variable Production rate Hexagonal Fuzzy Number Selling Price Dependent demand INFLATION
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Supply and Demand,Tax,Income,Profit and Proof of Goldbach’s Conjecture--Logic is the Basis of Correct Mathematical Measurement
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作者 Zhaocheng Wang 《Journal of Economic Science Research》 2022年第4期22-33,共12页
This paper demonstrates that Marshall’s logic on the supply and demand curve is not rigorous enough,that Coase’s theorem is flawed,and that the“Okishio Theorem”and Sweezy s logic are inadequate through empirical p... This paper demonstrates that Marshall’s logic on the supply and demand curve is not rigorous enough,that Coase’s theorem is flawed,and that the“Okishio Theorem”and Sweezy s logic are inadequate through empirical proof.By the way,the Goldbach conjecture is proved through clever mathematical proof.It shows that beautiful curves and mathematical formulas cannot be separated from reality and logic,and correct logic can play a correct role in market theory.In this paper,the analysis of the actual supply and demand curve,as well as the concepts and models of tax,profit rate and income,has positive practical significance for economic depression and stagflation. 展开更多
关键词 Supply and demand INCOME TAX Profit rate Goldbach conjecture
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