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221.
A new technique for improving the efficiency of propositional reasoning procedures is presented. The meta-search procedure, ND, is parameterized by a search procedure P and a real number for controlling the way in which P is applied to the given problem. Experiments using SATO on the domain of Crossword Puzzle Construction (CPC) illustrate the potential for ND. Variations of and future experiments with ND are discussed.  相似文献   
222.
Since eWOM provides a rich source of objective information about products or services, it has become one of the major ways in which consumers collect information about items they are interested in buying. However, the problem of eWOM overload makes it difficult to effectively collect this information, and may have adverse effects on their actual purchase behavior. eWOM content is characterized by unstructured text formats, oversimplified expressions, and newly coined phrases (textspeak), and these all contribute to the challenges that arise when analyzing eWOM. This study thus proposes an eWOM analysis method for analyzing eWOM, which may lead to a more effective method for analyzing eWOM content, extracting both positive and negative appraisals, and help consumers in their decision making. At the same time, the method proposed in this study can also be utilized as a tool to assist companies in better understanding product or service appraisals, thus translating these opinions into business intelligence and as the basis for product/service improvements.  相似文献   
223.
Abstract

Recently, Gao and Tu presented an efficient algorithm for robust low bit‐rate video transmission by using a partial backward decodable bit stream (PBDBS) approach. In this paper, we first present a multiple‐PBDBS (MPBDBS) approach to improve on the previous PBDBS approach. Next a mathematical theory is provided to minimize the error propagation length in each group of blocks (GOB). Further, a novel MPBDBS‐based algorithm is presented for robust video transmission. Experimental results demonstrate that our proposed MPBDBS‐based algorithm has better image quality when compared to the previous PBDBS‐based algorithm, but has some bit‐rate and execution‐time degradation. In our experiments, both single and two‐bit error models are investigated.  相似文献   
224.
Abstract

The strongest tradition of classroom‐environment research has focused on empirically testing the relationship between the classroom environment and student outcomes. This paper reports a study conducted within this general framework. Specifically, this research investigated the relationship between the classroom environment and self‐handicapping by students in Canadian high school mathematics classes. Results showed that the classroom environment accounted for appreciable proportions of variance in self‐handicapping, beyond that attributable to academic efficacy. Enhanced affective dimensions of the classroom environment were associated with reduced levels of self‐handicapping.  相似文献   
225.
In this article, the ‘information channel diagram’ (ICD) approach is introduced as a diagrammatical tool for modelling information flow during the delivery phase of organisations in which goods are deployed or delivered to customers. An initial review and evaluation of current tools for modelling information flow will be conducted based on the characteristics of information flow during the delivery phases in organisations. Diagrammatic primitives and a prescribed modelling methodology for developing an ICD will be presented, and a case scenario of the delivery phase of an organisation within the health care sector will be applied to demonstrate the use of the ICD. The article concludes by discussing some applications, generalisation potential and limitations of the ICD approach.  相似文献   
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228.
Confinement and crowding have been shown to affect protein fates, including folding, functional stability, and their interactions with self and other proteins. Using both theoretical and experimental studies, researchers have established the independent effects of confinement or crowding, but only a few studies have explored their effects in combination; therefore, their combined impact on protein fates is still relatively unknown. Here, we investigated the combined effects of confinement and crowding on protein stability using the pores of agarose hydrogels as a confining agent and the biopolymer, dextran, as a crowding agent. The addition of dextran further stabilized the enzymes encapsulated in agarose; moreover, the observed increases in enhancements (due to the addition of dextran) exceeded the sum of the individual enhancements due to confinement and crowding. These results suggest that even though confinement and crowding may behave differently in how they influence protein fates, these conditions may be combined to provide synergistic benefits for protein stabilization. In summary, our study demonstrated the successful use of polymer-based platforms to advance our understanding of how in vivo like environments impact protein function and structure.  相似文献   
229.

This paper addresses the robot-assisted rehabilitation of back pain, an epidemic health problem affecting a large portion of the population. The design is composed of two springs in series connected to an end-effector via a pair of antagonistic cables. The spring and cable arrangement forms an elastic coupling from the actuator to the output shaft. An input-output torque model of the series-elastic mechanism is established and studied numerically. The study also illustrates the variation of the mechanism’s effective stiffness by changing the springs’ position. In addition, we built a prototype of the robotic mechanism and design experiments with a robotic manipulator to experimentally investigate its dynamic characteristics. The experimental results confirm the predicted elasticity between the input motion and the output torque at the end-effector. We also observe an agreement between the data generated by the torque model and data collected from the experiments. An experiment with a full-scale robot and a human subject is carried out to investigate the human-robot interaction and the mechanism behavior.

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230.
Nitrogen-doped graphene-ZnS composite (NG-ZnS) was synthesized by thermal treatment of graphene-ZnS composite (G-ZnS) in NH3 medium. In the second step, the as-synthesized samples were deposited on indium tin oxide glass (ITO) by electrophoretic deposition for photocatalytic hydrogen evolution reaction. The as-prepared NG-ZnS-modified ITO electrode displayed excellent photocatalytic activity, rapid transient photocurrent response, superior stability and high recyclability compared to the pure ZnS and G-ZnS-modified ITO electrode due to the synergy between the photocatalytic activity of ZnS nanorods and the large surface area and high conductivity of N-graphene.  相似文献   
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