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41.
Systematic experiments with distribution games have shown that participants are strongly motivated by considerations of fairness and efficiency. This evidence, however, results mainly from experimental designs in which money is shared directly. Furthermore, fairness does not necessarily require equal payoffs, but may instead require equal allocations. We investigate experimentally the frame dependency of reaching equal (commodity or payoff) splits by systematically comparing net-trade proposals and payoff proposals for the same exchange economy with two traders, two commodities and multi-period negotiations. We can confirm the hypothesis that asking participants to allocate money directly, rather than more naturally via the allocation of commodities, is far from being harmless and likely overstates fairness and efficiency concerns. What is more, we try to apply the insights gained from our experiment to management problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
In this paper, a stream-based dataflow architecture is proposed, and its simulation model, which has helped to evaluate the effectiveness of the proposed architectural concept, is discussed. The machine integrates the conventional Von Neumann type of control flow subsystem with a dataflow processing element of token storage type. The control flow unit tackles the dynamic nature of the stream structure including input/output whereas the dataflow unit does the computation part in an applicative style. A pipelined version of the stream machine is also discussed. The effectiveness of the machine is studied by running a few example programs in the simulated machine. The machine is expected to be useful in real time signal processing applications.  相似文献   
43.
Interfacial cracks have several features which are different from those of cracks in homogeneous materials. Among those, the loading mode dependency of interfacial toughness has been a main obstacle to the widespread utilization of interfacial fracture mechanics. In this study, plasticity-induced toughening of an interface crack between an elastic-plastic material and an elastic material is studied. A useful relationship between the plastic dissipation and the plastic zone size is derived via an effective crack length model. Non-orthogonal stress modes for interface cracks are proposed on the basis of the plastic dissipation mechanism and a mixed-mode criterion for interfacial crack growth is also proposed using these stress modes. The non-orthogonal stress modes are able to represent the asymmetric behavior, mode-dependent toughening and ε-dependency of interfacial crack growth.  相似文献   
44.
45.
Rheological properties of the system gelatin + water at a polymer concentration of 5.0% by wt at a temperature of 301 K and an angular frequency of 0.628 rads–1 are presented and evaluated by use of the percolation theory. A frequency power law has been found close to the gel point from which a critical time range could be deduced in which the powers of the loss and storage modulus are the same. The times needed for the gelation from the percolation relations are close to the range where the exponents of the frequency power law relations are identical. The scaling coefficient Δ for physical gelation agrees very well with that found for chemical gelation by Durand and coworkers. Received: 9 October 2000 / Reviewed and accepted: 10 October 2000  相似文献   
46.
Reviews the books, Drogues et dépendances by Jef-Louis Bonnardeaux (1983) and Toxicomanies by Dollard Cormier (1983. The book by Bonnardeaux is clearly written and is accompanied by illustrations. However, one doubts the utility of the representation of many biochemical formulas. One wishes also for a better structuring of the various chapters. The book by Cormier is an excellent complement to the Bonnardeaux book. Drug addiction is presented as a life style expressing a solution to problems of existence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
47.
句子级事件检测任务目的是识别和分类事件触发词。现阶段工作主要将句子作为神经分类网络的输入,学习句子的深层语义信息,从而优化句子表示来改进事件检测任务的性能。该文发现除句子语义信息外,依存树包含的句法结构信息也有助于获取准确的句子表示。为此,该文采用双向长短时记忆网络对句子进行编码,捕获其语义信息;同时,设计图神经网络对句子的依存结构进行表示,获取其依存信息;此外,在对句子进行语义编码与依存编码时,该文利用自注意力机制使模型选择性地关注句子中的不同词,从而捕获句子中有助于事件检测的关键信息,并尽可能避免无关词的干扰;最后,该文提出门控机制,通过加权实现上述两种信息的动态融合。该文在自动文本抽取(automatic content extraction, ACE)数据集上进行实验,结果显示,该文提出的动态融合语义信息与依存信息的方法能更加有效地对句子进行编码,并捕获句子中的事件信息,在触发词识别与事件类型分类这两个子任务中,F1值均有较大提升,分别达到76.3%和73.9%。  相似文献   
48.
Dataflow analysis is a well-understood and very powerful technique for analyzing programs as part of the compilation process. Virtually all compilers use some sort of dataflow analysis as part of their optimization phase. However, despite being well-understood theoretically, such analyses are often difficult to code, making it difficult to quickly experiment with variants.To address this, we developed a domain-specific language, Analyzer Generator (AG), that synthesizes dataflow analysis phases for Microsoft's Phoenix compiler framework. AG hides the fussy details needed to make analyses modular, yet generates code that is as efficient as the hand-coded equivalent. One key construct we introduce allows IR object classes to be extended without recompiling.Experimental results on three analyses show that AG code can be one-tenth the size of the equivalent handwritten C++ code with no loss of performance. It is our hope that AG will make developing new dataflow analyses much easier.  相似文献   
49.
We investigate functional dependencies in databases that support complex values such as records, lists, sets and multisets. Therefore, an abstract algebraic framework is proposed that classifies data models according to the underlying types they support. This allows to emphasise the impact of the data types rather than the specifics of a particular data model.  相似文献   
50.
Rate-sensitive and triaxiality-dependent cohesive elements are used to simulate crack growth under quasi-static and dynamic loading conditions. The simulations are performed for a middle-cracked tension M(T) specimen made of an aluminum alloy (6XXX series). To consider the effect of stress triaxiality and strain rate on the cohesive properties, a single plane strain element obeying the constitutive equations of a rate-dependent Gurson type model has been used. The single element is loaded under various stress biaxiality ratios and strain rates and the obtained stress-displacement curves are considered as traction separation law for the cohesive elements. These curves are used for analyzing the aluminum M(T) specimen. The qualitative effects of constraint, strain rate, inertia and stress waves on the energy absorption of the specimen and crack growth are discussed.  相似文献   
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