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特征函数 1 ( 0,+∞ ) ( z )的一个光滑D.C.近似
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作者 修菀擎 陈浩东 任咏红 《应用数学进展》 2024年第7期3275-3280,共6页
特征函数1(0,+∞)(z)已经广泛地使用在实践中,许多重要的实际问题,如概率约束优化问题,可以表示为与特征函数相关的问题,该问题通常是非凸和非光滑的,因而在数值计算上有困难。本文构造了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数。... 特征函数1(0,+∞)(z)已经广泛地使用在实践中,许多重要的实际问题,如概率约束优化问题,可以表示为与特征函数相关的问题,该问题通常是非凸和非光滑的,因而在数值计算上有困难。本文构造了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数。讨论了函数φ(z,t)的一些性质。在一定条件下,当所涉及的参数足够小时,所提出的光滑近似函数收敛到1(0,+∞)(z)。基于该函数,构建了概率约束优化问题的一个等价的近似问题。 展开更多
关键词 特征函数 d.c.函数 光滑近似函数
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一类非凸D.C.约束优化问题的UV-分解理论 被引量:1
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作者 王炜 王雯 《大连民族学院学报》 CAS 2009年第3期229-231,234,共4页
UV-分解理论是近年来解决非光滑凸函数的二阶近似的一种有效的方法,并应用于解决非光滑凸函数的最优化问题。主要应用UV-分解理论对于一类D.C.函数的约束优化问题进行研究,借助于近似次微分的概念,得到类似的UV-空间分解,以及空间分解... UV-分解理论是近年来解决非光滑凸函数的二阶近似的一种有效的方法,并应用于解决非光滑凸函数的最优化问题。主要应用UV-分解理论对于一类D.C.函数的约束优化问题进行研究,借助于近似次微分的概念,得到类似的UV-空间分解,以及空间分解下的相应U-Lagrange函数与其最优解集W(u)的相关性质和二阶近似的结果。 展开更多
关键词 非光滑最优化 d.c.函数 UV-分解 U—Lagrange函数
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特征函数1_(0,+∞)(z)的一个光滑D.C.近似函数 被引量:2
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作者 任咏红 池慧 姜欢 《辽宁师范大学学报(自然科学版)》 CAS 2016年第4期438-442,共5页
基于Pinar-Zenios光滑和函数,提出了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数,讨论了函数的性质,证明了当参数充分小时,光滑函数收敛于特征函数1(0,+∞)(z),并在一定的条件下,建立了概率约束优化问题的一个等价的光滑近似问题.
关键词 特征函数 Pinar-Zenios光滑和函数 d.c.函数 光滑近似
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D.C.隶属函数模糊集及其应用(II)——D.C.隶属函数模糊集的万能逼近性 被引量:3
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作者 邱中华 李雷 《模糊系统与数学》 CSCD 北大核心 2006年第2期50-60,共11页
本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万... 本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万有逼近性。探讨了D.C.隶属函数模糊集与模糊数之间的关系,给出了用D.C.隶属函数模糊集逼近模糊数的-εC e llina逼近形式,得到模糊数与D.C.函数之间的一个对应算子,指出了用模糊数表示D.C.函数的问题。 展开更多
关键词 d.c.隶属函数模糊集 逼近 模糊数
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D.C.隶属函数模糊集及其应用(I)——D.C.隶属函数模糊集基本概念与性质 被引量:4
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作者 李雷 《模糊系统与数学》 CSCD 北大核心 2005年第4期45-53,共9页
本文是D.C.隶属函数模糊集及其应用系列研究的第一部分。建立了D.C.隶属函数模糊集的基本概念。探讨了D.C.隶属函数模糊集的基本性质和D.C.隶属函数模糊集对一些常见的重要t模、余模和伪补的封闭性。并以此建立了丰富的模糊数学应用模型。
关键词 d.c.隶属函数 模糊集 T模 余模 伪补
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压缩感知中的概率约束优化模型及其D.C.近似
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作者 任咏红 曹丽娜 +1 位作者 姜欢 曲文静 《辽宁师范大学学报(自然科学版)》 CAS 2017年第2期154-158,共5页
带有噪声的压缩感知信号重建模型可表示为l_1-范数问题.为了满足使用少量观测值重构出高精度的图像,在设置观测矩阵时需要满足受限等距性(RIP)和非相干性,然而判断一个矩阵的RIP是非常困难的.针对观测矩阵的不确定性,将该模型转化为具... 带有噪声的压缩感知信号重建模型可表示为l_1-范数问题.为了满足使用少量观测值重构出高精度的图像,在设置观测矩阵时需要满足受限等距性(RIP)和非相干性,然而判断一个矩阵的RIP是非常困难的.针对观测矩阵的不确定性,将该模型转化为具有概率约束的随机优化模型,即在约束条件以很大的概率被满足的情况下,求解最小l_1-范数问题.构建了概率约束函数的一个D.C.近似函数,讨论了函数的性质,建立了相应的D.C.近似问题,证明了D.C.近似问题与概率约束优化问题的等价性. 展开更多
关键词 压缩感知 概率约束 d.c.近似
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概率约束优化问题的一个光滑D.C.近似 被引量:1
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作者 任咏红 曹丽娜 《辽宁师范大学学报(自然科学版)》 CAS 2018年第1期17-21,共5页
概率约束优化问题通常是非凸且非光滑的,因而在数值计算上存在困难.基于Pinar-Zenios光滑和函数,建立了概率约束优化问题的一个光滑D.C.近似问题,提出了求解光滑D.C.近似问题的序列凸近似(SCA)算法,分析了初始解的选取方法,并讨论了算... 概率约束优化问题通常是非凸且非光滑的,因而在数值计算上存在困难.基于Pinar-Zenios光滑和函数,建立了概率约束优化问题的一个光滑D.C.近似问题,提出了求解光滑D.C.近似问题的序列凸近似(SCA)算法,分析了初始解的选取方法,并讨论了算法的收敛性,收敛定理表明可以由SCA算法可以得到光滑D.C.近似问题的KKT点,并且在迭代过程中,确保了由SCA算法生成的解序列的极限点是近似问题的KKT点. 展开更多
关键词 概率约束 Pinar-Zenios光滑和函数 光滑d.c.近似 序列凸近似算法
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不可微D.C.规划问题的全局最优性充要条件 被引量:2
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作者 叶留青 《河南师范大学学报(自然科学版)》 CAS CSCD 2003年第2期15-17,共3页
本文给出了一类不可微D .C .
关键词 不可微d.c.规划 全局最优性 充要条件 Ε-最优解 非凸不可微规划 不可微凸函数
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求解一般D.C.规划的全局最优解
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作者 徐俊彦 苗壮 刘庆怀 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第6期1058-1062,共5页
给出一种求解一般D.C.规划非孤立全局最优解的算法.该算法克服了目前一些逼近算法在计算过程中有时得到的解为不可行解、甚至远离真正全局最优解的问题.数值结果表明了算法的有效性.
关键词 全局优化 一般D C 规划 非孤立最优解
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D.C.乘性规划的全局优化算法
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作者 周雪刚 《长江大学学报(自然科学版)》 CAS 2011年第4期1-4,284,共4页
讨论了凸集上的D.C.乘性规划的全局优化算法。首先通过引入辅助变量将D.C.乘性规划问题转化为一个等价的D.C.规划问题;再综合利用分支定界与外逼近方法求解等价问题;最后用一个实例说明算法的实用性。
关键词 d.c.乘性规划 全局优化 割平面 锥细分
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基于最优D.C.分解的单二次约束非凸二次规划精确算法 被引量:2
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作者 郑小金 《运筹学学报》 CSCD 2009年第3期111-118,共8页
本文提出一种基于最优D.C.分解的单二次约束非凸二次规划精确算法.本文首先对非凸二次目标函数进行D.C.分解,然后对D.C.分解中凹的部分进行线性下逼近得到一个凸二次松弛问题.本文证明了最优D.C.分解可通过求解一个半定规划问题得到,而... 本文提出一种基于最优D.C.分解的单二次约束非凸二次规划精确算法.本文首先对非凸二次目标函数进行D.C.分解,然后对D.C.分解中凹的部分进行线性下逼近得到一个凸二次松弛问题.本文证明了最优D.C.分解可通过求解一个半定规划问题得到,而原问题的最优解可以通过计算最优凸二次松弛问题的满足某种互补条件的解得到.最后,本文报告了初步数值计算结果. 展开更多
关键词 运筹学 单二次约束非凸二次规划问题 最优d.c.分解 半定规划 精确算法
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A Hierarchical Framework for Visualising and Simulating Supply Chains in Virtual Environments 被引量:3
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作者 Hai-Yan Zhang Institute of Engineering Mechanics, China Earthquake Administration, 29 Xuefu Road, Harbin 150018, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK Zheng-Xu Zhao Department of Instrumentation Science and Engineering, Southeast University, Nanjing 210096, PRC School of Mechanical & Manufacturing Engineering, Shandong University, Jinan 250061, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK 《International Journal of Automation and computing》 EI 2005年第2期144-154,共11页
This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to sim... This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to simulate processes and activities in supply chain management. This will enable those who are involved in these processes and activities to gain an intuitive understanding of them, so as to design robust supply chains and make correct decisions at the right time. A framework system and its hierarchical structure for visualising and simulating supply chains in virtual environments are reported and detailed in this paper. 展开更多
关键词 Virtual environments supply chains 3D visualising SIMULATING WEB based systems
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The Framework Model of Supply-Chain Process in CALS Environment 被引量:1
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作者 HU Jian-yang, WANG Zhi-ge, MA Shi-hua, SHEN Ling (School of Management, Huazhong University of Science & Technology, W uhan 430074, China ) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期270-271,共2页
E-supply chain is the trend of the supply chain ma na gement. However, building E-supply chain depends on business process improvemen t and re-engineering, which becomes one of the important aspects in supply chai n m... E-supply chain is the trend of the supply chain ma na gement. However, building E-supply chain depends on business process improvemen t and re-engineering, which becomes one of the important aspects in supply chai n management. However, the supply chain process re-engineering and improvement is constrained because of lack of integrating operation framework and standards based on information management. We find that the idea of CALS origins from DoD of USA can solve the problems very well. CALS is the abbreviation of "continues acquisition and life- cycle support". It is an information strategy adopted by many developed counties. The final objective of the CALS is that government a nd industry can generate, exchange, manage and use all the digital information t hroughout the lifecycle of a product in virtue of adopting the international and national standards, improving existing business process and introducing advance d technology. The Integrated Digital Environment (IDE) created by CALS provides a brand new operation mode for consumer, contractor and supplier in supply chain . Besides, a series mutual standard is involved in CALS system. These standards and the standardization technology would be applied widely in the supply chain. This study mainly focuses on supply chain process in CALS environment, and puts forward a framework model of supply chain process. Then the study analyzes the c haracteristics of the model, which includes the application of standards and inf ormation technology, and finally discusses on methods to achieve the supply chai n process in CALS environment. 展开更多
关键词 supply chain business process re-engineering C ALS
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The Convergence of the Steepest Descent Algorithm for D.C.Optimization 被引量:1
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作者 SONG Chun-ling XIA Zun-quan 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期131-136,共6页
Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and c... Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and constrained quasi-differentiable programming is proved. 展开更多
关键词 nonsmooth optimization D. C. optimization upper semi-continuous lower semi-continuous steepest descent algorithm CONVERGENCE
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引用“P.D.C.A循环法”实施对护士长管理能力培训的体会 被引量:3
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作者 尹凤英 《国际医药卫生导报》 2001年第10A期14-14,共1页
目的 提高护士长综合管理能力。方法 引用质量管理中的“P.D.C.A循环法”通过对护士长进行(1)现代管理基础理论,护理管理知识学习;(2)实行护士长目标责任制管理;(3)新任职护士长轮岗制度。效果 (1)11名护士长年度业绩考核,优秀3名占27%... 目的 提高护士长综合管理能力。方法 引用质量管理中的“P.D.C.A循环法”通过对护士长进行(1)现代管理基础理论,护理管理知识学习;(2)实行护士长目标责任制管理;(3)新任职护士长轮岗制度。效果 (1)11名护士长年度业绩考核,优秀3名占27%,称职7名,基本称职1名;(2)与97年相比全年护理质量综合评分上升至98.2%,护理事故及严重差错发生率为0,患者满意度上升至96.7%。九八年被评为百佳医院。结论 护理部要把人才培养放在选拔之前,运用质量循环管理精神不断提高护士长自身素质及管理能力,使之成为具有丰富管理知识的临床专家型护理管理者,以适应新的时期护理工作发展的需要。 展开更多
关键词 “P.d.c.A循环法” 护士长 管理能力 培训
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Risk Assessment of Agricultural Products Supply-Chain Finance Based on D-S Theory 被引量:3
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作者 Yuan Zhang Lian Duan Gefu Zhang 《American Journal of Computational Mathematics》 2014年第4期366-375,共10页
Agricultural products supply-chain finance, as one of the solutions to the issue of “capital problems” of agriculture, countryside and farmers, has proposed a kind of characteristics model to assess the risk of agri... Agricultural products supply-chain finance, as one of the solutions to the issue of “capital problems” of agriculture, countryside and farmers, has proposed a kind of characteristics model to assess the risk of agricultural production, processing and marketing, which can improve the issue of farmers and enterprises lacking of funds. This model is proposed on the basis of uncertain information processing method of D-S theory and its data combination rules, combined with the “discount rate” correction model, and it includes a risk assessment index system of agricultural products supply-chain finance, fully considering the five aspects of production, processing, marketing, cooperation of supply chain and collateral. At last, a taro supply chain is taken for example. And the risk assessment of its supply-chain finance based on this model has been discussed in detail. And the result has proved that the model and its algorithm are practical and feasible. 展开更多
关键词 supply-Chain FINANCE Risk AGRICULTURAL Products TARO D-S Theory
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桂东北D/C界线沉积特征及对台盆相间演化的启示 被引量:1
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作者 吴亮君 王璞珺 +11 位作者 吴继文 韦盛亮 户景松 吕勇 潘明 周嘉铭 林宇 廖家飞 韦伟 韦艾辰 李喜林 苏光样 《地质学报》 EI CAS CSCD 北大核心 2024年第4期1244-1262,共19页
台盆相间是桂东北泥盆纪和石炭纪沉积的重要特色,而D/C界线又是台盆相间沉积最突出的一个时段之一。文章回顾并评述了桂东北D/C界线的研究历程、相序划分、主要代表剖面,认为桂东北D/C界线可划分为碎屑岩相序和碳酸盐岩相序以及它们的... 台盆相间是桂东北泥盆纪和石炭纪沉积的重要特色,而D/C界线又是台盆相间沉积最突出的一个时段之一。文章回顾并评述了桂东北D/C界线的研究历程、相序划分、主要代表剖面,认为桂东北D/C界线可划分为碎屑岩相序和碳酸盐岩相序以及它们的过渡类型。通过对20条典型剖面的岩性组合特征对比,恢复了桂东北D/C界线海平面相对下降期的岩相古地理,结果显示桂东北在该时期主要存在柳州、桂林两大台地以及多个小型台地,台地间普遍发育快速相变的台沟、盆地沉积,石炭纪初期海水变浅,台地分布范围显著扩大,江南古陆供给增强,台盆相间格局迅速发展。为了进一步探讨桂东北D/C界线的演化过程和背后的控制因素,文章分析了广西整体的台盆相间演化的阶段性、同沉积构造作用以及海平面变化的影响,梳理了台盆相间演化过程中沉积环境分异与构造运动-海平面的关系,认为在滇黔桂裂谷盆地在持续断陷发展的前提下,桂东北D/C界线沉积分异的主要原因可能是受冈瓦纳大陆冰川形成与消融导致的海平面异常波动,以及柳江运动引发的局部同沉积断陷强度差异变动影响,且构造和沉积要素在D/C界线的耦合作用达到最强,最终促进桂东北台盆相间格局在D/C界线达到鼎盛。在此模式下,可以将台盆相间的演化划分为4个阶段,早泥盆世中期—晚期为台盆相间格局的孕育期,早泥盆世晚期—中泥盆世晚期沉积开始分异,为台盆相间格局的发展期,晩泥盆世—早石炭世台-盆出现强烈分割,海平面异常下降和柳江运动同时作用于沉积,为台盆相间格局的鼎盛期,早石炭世之后,台盆相间沉积维持了一定时期的强度,晚石炭世开始海水逐步恢复正常后台盆相间逐渐减弱,为台盆相间格局的衰退期。 展开更多
关键词 台盆相间 D/C界线 桂东北 广西 泥盆纪 石炭纪 古地理 柳江运动
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Digital arc welding power supply based on real-time operating system
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作者 张红兵 黄石生 周漪清 《China Welding》 EI CAS 2007年第3期1-5,共5页
A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculat... A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder. 展开更多
关键词 micro C/OS-Ⅱ real-time operating system DIGITIZATION arc welding power supply
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Novel Cascade Refrigeration Cycle for Cold Supply Chain of COVID-19 Vaccines at Ultra-Low Temperature -80°C Using Ethane (R170) Based Hydrocarbon Pair
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作者 Tarek A. Mouneer Abdelrahman M. Elshaer Mohamed H. Aly 《World Journal of Engineering and Technology》 2021年第2期309-336,共28页
Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80<span style="white-space:nowrap;">°</span>C to transport and store its COVID-19 vaccines... Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80<span style="white-space:nowrap;">°</span>C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard. 展开更多
关键词 Cascade Refrigeration Cold supply Chain COVID-19 Vaccine Ultra-Low Temperature -80°C Hydrocarbon Refrigerants Refrigerant Pair
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An Activity in Japan for Realizing CO2-Free Hydrogen Global Supply Chains
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作者 Masaharu Sasakura Yuki Ishimoto Ko Sakata 《Journal of Chemistry and Chemical Engineering》 2014年第2期163-170,共8页
The current basic energy plan of Japan was authorized in the Cabinet in June 2010, in which ambitious energy and environmental targets and policies giving nuclear power a pivotal role toward 2030 were described. At pr... The current basic energy plan of Japan was authorized in the Cabinet in June 2010, in which ambitious energy and environmental targets and policies giving nuclear power a pivotal role toward 2030 were described. At present, the Japanese government has been forced to review the basic energy plan in the wake of the great east Japan earthquake occurred on March 11, 2011 followed by the severe accident at the nuclear power plants in Fukushima. Before the disaster, the IAE (institute of applied energy) had realized that it was not clear how CO2-free hydrogen would contribute to solving various energy and environmental issues, or that prospects were not clear for large demand of CQ-free hydrogen other than FCVs (fuel cell vehicles). In this connection, the authors organized a voluntary "Concept Study Group (in short)" in March 2011 and held four meetings until the end of March 2012. Through the quantitative studies using IAE's simulation model (GRAPE), the common recognition was built in the concept study group that hydrogen could contribute to energy security and increase in zero-emissions electric power ratio in Japan. It was also estimated that global CO2-free hydrogen supply chains could be realized by degrees after 2020. Based on these results, the authors made a proposal that hydrogen should be added in the primary energy constitution for new basic energy plan to the Japanese government because imported hydrogen could be considered as a pseudo-primary energy like LNG (liquefied natural gas). Now, the succeeding "Action Plan Study Group (in short)" has been held focusing on hydrogen demand in various applications, future pictures of CO2-free hydrogen chains and road maps. Activity results of the "Concept Study Group" are shown here. 展开更多
关键词 C02-free hydrogen global hydrogen supply chains simulation with GRAPE liquefied hydrogen methylcyclohexane.
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