A comparative study on thermo-economic performance between subcritical and transcritical Organic Rankine Cycles under different heat source temperatures

In this paper, the net power output, exergy efficiency and levelized energy cost of system were selected as performance indicators for assessing Organic Rankine Cycle （ORC）. Firstly, the turbine inlet temperature and pressure meeting the requirement of pinch point temperature difference of evaporator in transcritical ORC （trans-ORC） were determined based on performance opti- mization. Subsequently, the thermo-economic performance of a subcritical ORC （sub-ORC） using R601 as working fluid and a trans-ORC using R134a as working fluid were compared under different heat source temperatures and a fixed outlet temperature of flue gas. Results show that for trans-ORC, when the pinch point temperature difference of evaporator lies between the inlet and outlet of evaporator, a lower inlet pressure of turbine is favorable; when the pinch point temperature difference of evaporator is located at the outlet of evaporator, there exists an optimal inlet pressure of turbine. Either for sub-ORC or trans-ORC, the net power output increases and levelized energy cost decreases with the increase in heat source temperature. For sub-ORC, exergy efficiency of system increases monotonously with heat source temperature, while for trans-ORC, exergy efficiency of system grows up firstly and then reduces （or keeps constant） with the increasing of heat source tem- perature. Moreover, for net power output and exergy efficiency of system, there exist a range of heat source temperatures making trans-ORC better than sub-ORC, and the heat source temperature region extends with the increase in pinch point temperature difference of evapo- rator. For levelized energy cost of system, the sub-ORC is always superior to trans-ORC.     

针刀松解弹响拇指

目的：探讨针刀松解治疗板机拇指的疗效．方法：弄清楚弹响拇指的腱鞘、肌腱籽骨等的精细解剖和动态解剖基础上,使用定点画线、听声法、针刀松解腱鞘等治疗86例板机拇指．结果：86例病人,均为一次完成松解,未发生副损伤,无一例复发．结论：在安全线上进针刀,做到眼、手、耳密切配合,一次针刀松解,便可成功,此法可值得推广．     

不同的时代 一样的叹息——简·奥斯丁与王海鸽小说异同浅析

简·奥斯丁和王海鸽是表现爱情与婚姻题材的两位杰出的女作家,她们作品的相同之处,一是用小题材来体现社会,二是表现了女性角色的依附地位,不同之处在于主体风格不同：一“悲剧”一“喜剧”的表现方式,引领人们通向两位作家不同的心灵世界。     

“比较文学”的教与学

“比较文学”课程专业性、学术性极强,内容多课时少,讲求高质量的课堂效果,宜针对学生的知识储备、接受特点在教学方法上有所革新。利用已有的比较文学学术成果阐释学科原理、解析学科研究方法,结合实例研讨重点、难点、疑点问题,学生提交论文分析报告的例证分析性教学,有助于提高学习效率,是行之有效的重要方法。     

《比较文学原理》课本科教学的实验及思考

从研究个案带动研究类型的教学、重视中国比较文学史和突出中国问题、强调学术外语和英文原著片断的阅读、寻求教师个人学识与课程基础性之间的平衡这几个方面,陈述和分析了《比较文学原理》（又名《比较文学概论》）课的教学实验和改革。     

中美两国政府科技报告制度建设比较分析研究

科技报告是记录科研项目成果或进展情况的报告,在知识传播和利用中发挥着重要作用,世界各国特别重视科技报告制度的建设,其中美国的科技报告制度建设最为全面、成效最为突出,对中国优化建设科技报告制度具有借鉴意义。本文对中美两国科技报告的类型、政策法规、职责分工、开放共享等方面的制度进行了梳理分析,揭示出中国科技报告存在管理制度不够系统全面、开放共享操作性不强、收藏管理范围有待拓宽、产权归属有待明确等问题。最后,针对中国科技报告制度建设的不足与短板,提出进一步优化的对策建议与展望：1）实施科技报告军口与民口分类管理制度,涉及国防科技内容的科技报告按照《国防科技工业科技报告暂行管理办法》进行管理;2）实施民口科技报告统一管理制度,将政府资助的科研项目报告进行统一收藏管理;3）加强科技报告理念意识建设,提升全民科技报告思想认识;4）将科技报告纳入科研项目管理,全过程跟踪管理;5）加快科技报告质量评价体系建设,推动科技报告质量全面提升;6）明确科技报告知识产权归属,解决产权归属判定难问题;7）加强科技报告开放共享管理,推动科技报告尽可能开放共享;8）加强科技报告科研诚信建设,树立良好的作风和学风。     

Ethnographic analogy,the comparative method,and archaeological special pleading

Ethnographic analogy, the use of comparative data from anthropology to inform reconstructions of past human societies, has a troubled history. Archaeologists often express concern about, or outright reject, the practice—and sometimes do so in problematically general terms. This is odd, as (or so I argue) the use of comparative data in archaeology is the same pattern of reasoning as the ‘comparative method’ in biology, which is a well-developed and robust set of inferences which play a central role in discovering the biological past. In pointing out this continuity, I argue that there is no ‘special pleading’ on the part of archaeologists in this regard: biologists must overcome analogous epistemic difficulties in their use of comparative data. I then go on to emphasize the local, empirically tractable ways in which particular ethnographic analogies may be licensed.     

结构化模型中违约概率的比较静态分析及实证

由于违约概率估计在金融机构中风险测度与风险管理的重要性，基于信用风险管理的结构化方法，应用Black-Scholes-Merton的结构化模型计算客观违约概率，分析客观违约概率的比较静态特征，实证结果表明，比较静态特征在信用风险管理中起到有重要的作用。     

基于主成分分析的大学课程国际化程度比较研究

对国内985大学、有研究生院的大学、211大学及一般性大学学生语言与课程设置的国际化程度的问卷调查数据进行统计分析,选取对入读学生是否有某种外语要求、对本科生毕业的外语要求、对本科生开课中的国际化课程所占比重三个指标分别刻画大学对学生外语要求的国际化程度,用主成分分析法对这三个指标进行组合,对不同指标对大学本科生课程设置的国际化程度的影响状况进行比较研究,探索大学课程设置创新的新思路.