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111.
The performances of two systems using hydrocarbon pairs are compared. The first system is an absorption heat pump, comprising a rectification column separator and a mixer comprising a single-stage cell. In this case, five hydrocarbon pairs are used. In the second system, the authors compare the performances of three hydrocarbon pairs in two heat pumps with one or two stages in the mixer. It was shown that the best performances are obtained using pairs with the most similar chemical compositions.  相似文献   
112.
Demonstrative Suffering: The Gestural (Re)embodiment of Symptoms   总被引:1,自引:0,他引:1  
Despite the long-standing interest in emotion and bodily conduct, there remains relatively little research concerned with how gestures are used with talk and within interaction to reveal emotional and personal experience. In this article, the author considers the medical consultation and, in particular, the ways in which patients attempt to reveal their experience of illness to the doctor. The paper examines how gesture and other forms of bodily conduct are used to transform symptoms into suffering; to display, enact, and (re)embody medical problems and difficulties. The analysis is based on videorecordings of primary health care consultations and focuses on the social and interactional organization of demonstrative suffering.  相似文献   
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114.
This paper introduces a new mathematical model of the master-slave architecture for distributed evolutionary computations (EC). This model is validated using a concrete implementation based on the Distributed BEAGLE C++ framework. Results show that contrary to (current) popular belief, master-slave architectures are able to scale well over local area networks of workstations using off-the-shelf networking equipment. The main properties of the master-slave are also compared with those of the more mainstream island-model.  相似文献   
115.
We consider a system defined as the product of a finite set of periodic systems on cyclic groups. It is of interest to determine if certain subgroups and unions of subgroups of the state set are reachable from a specified initial state, and in particular to determine the computational complexity of verifying such reachability. These questions are motivated by certain problems that arise in the modelling and control of discrete event systems and certain forms of periodic scheduling. Our main result is that deciding whether or not the union of a certain set of subgroups is reachable or not is NP-complete.  相似文献   
116.
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented  相似文献   
117.
118.
The chemistry and electrochemistry of electroplating baths based on Pd(NH3)2Br2 and Pd(NH3)2(NO2)2 has been investigated and compared with that previously reported for Pd(NH3)2Cl2. It is shown that electroactive species in all the baths is Pd(NH3) 4 2+ and, hence, the mechanisms and current efficiencies for the cathodic deposition of palladium metal are similar in all three media. On the other hand, only in bromide electrolytes is the palladium found to dissolve anodically.  相似文献   
119.
120.
Electrocatalyst materials used in industrial water electrolysis equipment must meet stringent requirements for long-term stability. Low electrode overvoltages must be sustained over prolonged periods of normal operation, including power interruptions. This paper presents an overview of the catalyst systems currently favoured for use in alkaline electrolyte. Performance data covering test periods exceeding 30 000 h are presented for representative commercial electrocatalysts. Results obtained in 100 000-A unipolar cells are correlated in detail with expectations based on measurements in laboratory and pilot-plant equipment.Particular attention is given to the effects of open-circuit conditions on electrode stability. An accelerated reverse-potential cycling test is described which allows identification of materials expected to withstand industrial operating conditions. It is found that the better materials which have been identified can be used with confidence, at least in electrolysers of the unipolar design in which potential variations encountered during current interruptions are modest.  相似文献   
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