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61.
Environmental conditions and the interplay of cognitive and affective processes both exert influences on bidding behavior. This paper brings the above together, considering how the (external) auction environment determines the impact of (internal) cognitive and affective processes on bidding behavior, assessed in comparison to the optimal bid. Two aspects of the auction environment were considered, namely auction dynamics (low: first-price sealed-bid auction, high: Dutch auction) and value uncertainty (low, high). In a laboratory experiment, we assess bidders’ cognitive workload and emotional arousal through physiological measurements. We find that higher auction dynamics increase the impact of emotional arousal on bid deviations, but not that of cognitive workload. Higher value uncertainty, conversely, increases the impact of cognitive workload on bid deviations, but not that of emotional arousal. Taken together, the auction environment is a critical factor in understanding the nature of the underlying decision process and its impact on bids.  相似文献   
62.
In this work, we present a method of decomposition of arbitrary unitary matrix \(U\in \mathbf {U}(2^k)\) into a product of single-qubit negator and controlled-\(\sqrt{\text{ NOT }}\) gates. Since the product results with negator matrix, which can be treated as complex analogue of bistochastic matrix, our method can be seen as complex analogue of Sinkhorn–Knopp algorithm, where diagonal matrices are replaced by adding and removing an one-qubit ancilla. The decomposition can be found constructively, and resulting circuit consists of \(O(4^k)\) entangling gates, which is proved to be optimal. An example of such transformation is presented.  相似文献   
63.
Recently, Brooklyn has seen an explosion of drag culture, with dozens of performers taking the stage in any given week. Social media plays a vital role for members of this community, simultaneously allowing self‐promotion and community solidarity. Drawing on focus group interviews, we analyze the communication practices of Brooklyn's drag performers, examining both the advantages and drawbacks of social media platforms. Using conceptual frameworks of faceted identity and relational labor, our discussion focuses on affordances and constraints of multifaceted identity in online contexts and theories of seamful design. We contend that by analyzing online communication practices of drag performers, it becomes possible to identify gaps between embedded ideologies of mainstream social media technologies and the localized values of outsider communities.  相似文献   
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Numerical modelling of natural draft wet-cooling towers is considered in this paper. Development of a complete CFD model capable of predicting cooling tower performance under various operating conditions is presented. A step-by-step approach is employed, thus one-dimensional numerical modelling of counterflow heat and mass exchangers is extensively presented first. This is followed by reduced order modelling of heat and mass transfer in cooling tower fills by means of proper orthogonal decomposition radial basis function networks. Then the approaches in modelling of droplet zones (rain and spray zones) are discussed. Finally the two and three-dimensional CFD models are discussed.  相似文献   
67.
Sealed nanofluidic channels with cross-sections as small as 60 nm × 60 nm were created in polymer bilayers using the focused X-rays of a scanning transmission X-ray microscope. These structures were then characterized by near-edge X-ray absorption fine structure spectromicroscopy, atomic force microscopy and scanning electron microscopy. The cross-sectional area of the nanochannels could be tuned by adjusting the area patterned in x and y and/or manipulating the bottom layer thickness. The maximum length was found to be limited by the efficiency of excavation of patterned material out of the channel, and the stability of the polymer overlayer which seals the channel. Schemes toward interfacing these nanochannels with conventional microfluidics are discussed.  相似文献   
68.
We describe a performance study of a multi-zone application benchmark implemented in several OpenMP approaches that exploit multi-level parallelism and deal with unbalanced workload. The multi-zone application was derived from the well-known NAS Parallel Benchmarks (NPB) suite that involves flow solvers on collections of loosely coupled discretization meshes. Parallel versions of this application have been developed using the Subteam concept and Workqueuing model as extensions to the current OpenMP. We examine the performance impact of these extensions to OpenMP and compare with hybrid and nested OpenMP approaches on several large parallel systems.  相似文献   
69.
Adam Drozdek 《AI & Society》1995,9(4):389-395
The question whether or not computers can think was first asked in print by Alan Turing in his seminal 1950 article. In order to avoid defining what a computer is or what thinking is, Turing resorts to the imitation game which is a test that allows us to determine whether or not a machine can think. That is, if an interrogator is unable to tell whether responses to his questions come from a human being or from a machine, the machine is imitating a human being so well that it has to be acknowledged that these responses result from its thinking. However, then as now, it is not an indisputable claim that machines could think, and an unceasing stream of papers discussing the validity of the test proves this point. There are many arguments in favour of, as well as against, the claims borne by the test, and Turing himself discusses some of them. In his view, there are mice possible objections to the concept of a thinking machine, which he eventually dismisses as weak, irrelevant, or plain false. However, as he admits, he can present no very convincing arguments of a positive nature to support my views. If I had I should not have taken such pains to point out the fallacies in contrary views.  相似文献   
70.
Ultrasonic surface waves are suitable for the characterization of surface hardened materials. This is shown on laser hardened turbine blades. The martensitic microstructure within the surface layer of surface hardened steels has a lower surface wave propagation velocity than the annealed or normalized substrate material. Because the propagation velocity depends on the ratio of layer thickness to wavelengthd/, its measurement allows the determination of the hardening depth. If the surface wave frequency is high enough, the surface wave propagates mainly within the hardened layer. A correlation of the surface wave velocity to the surface hardness has been found. Because the variation of the surface velocity in hardened steels is small, a high measurement accuracy is necessary to obtain the interesting hardening parameters with sufficient certainty. Therefore, a measuring arrangement has been developed where laser pulses, guided by optical fibers to the surface hardened structure, generate simultaneously surface wave pulses at two different positions. The two ultrasonic pulses are received by a piezoelectric transducer. The surface wave velocity is obtained from the time delay between these pulses which is determined by the cross-correlation method. To evaluate simultaneously surface waves with different penetration depths from the same signal acquisition, digital filtering has been used in connection with the cross-correlation.  相似文献   
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