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11.
In engineering practice, moisture absorption test is generally used for quality control purposes and to measure the degradation of the quality for the composite materials. The objectives of this study are to investigate the value of Fickian diffusivity constant, moisture equilibrium content and correction factor for the natural fiber composites. Tests were carried out on composite plates, which was a combination of sugar palm fiber and epoxy resins and two different fiber compositions have been chosen which were 10% and 20% by weight. Pure epoxy plates have been used for the control measures. The specimens were oven dried for 60 h in an air-circulating oven operated with 108 °C before being immersed in the constant temperature water bath, which the distilled water was set at 40 °C for the moisture absorption behavior test for 33 days. From this study, plates with 20% fiber loading possessed the highest amount of moisture prior to the moisture absorption behavior test, which is 0.93%. In moisture absorption behavior test, the corrected value of Fickian diffusivity constant for the 20% fiber loading is 3.76 × 10−7 mm2/s, which is the highest among other composites. It is shown that, for composite plates that contain higher fiber composition, the moisture absorption rate is even higher.  相似文献   
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The Cryogenic Dark Matter Search (CDMS) utilizes large mass, 3″ diameter × 1″ thick target masses as particle detectors. The target is instrumented with both phonon and ionization sensors and comparison of energy in each channel provides event-by-event classification of electron and nuclear recoils. Fiducial volume is determined by the ability to obtain good phonon and ionization signal at a particular location. Due to electronic band structure in germanium, electron mass is described by an anisotropic tensor with heavy mass aligned along the symmetry axis defined by the [111] Miller index (L valley), resulting in large lateral component to the transport. The spatial distribution of electrons varies significantly for detectors which have their longitudinal axis orientations described by either the [100] or [111] Miller indices. Electric fields with large fringing component at high detector radius also affect the spatial distribution of electrons and holes. Both effects are studied in a 3 dimensional Monte Carlo and the impact on fiducial volume is discussed.  相似文献   
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A survey on 143 university students was conducted to examine what motives young adults have for Facebook use, which of those motives were endorsed more than the others, and how those motives were related to the tendency of expressing one’s “true self” through Facebook use. According to the results, primary motive for Facebook use was to maintain long-distance relationships. This motive was followed by game-playing/entertainment, active forms of photo-related activities, organizing social activities, passive observations, establishing new friendships, and initiating and/or terminating romantic relationships. Another interesting result was that individuals’ tendency for expressing one’s true self on the Net had an influence on their Facebook use motives: The ones with high tendency to express their true self on the Internet reported to use Facebook for establishing new friendships and for initiating/terminating romantic relationships more than the individuals’ with low and medium levels of the same tendency did.  相似文献   
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OBJECTIVE: To determine the extent of communication problems that arose from patients whose primary language was non-English presenting to an inner city accident and emergency (A&E) department. METHODS: A prospective survey over seven consecutive days during September 1995. All adult patients other than those directly referred by their general practitioner to an inpatient team had a questionnaire completed by the A&E doctor first seeing the patient. The doctor recorded language ability and form of interpreter used, and estimated any prolongation of the consultation and ability to improve communication by the use of additional services. RESULTS: 103 patients (17%) did not speak English as their primary language; 55 patients (9.1% of the study population) had an English language ability rated as other than good, and 16 (29%) of these consultations could have been improved by the use of additional interpreter services; 28 patients overall (4.6% of the study population) required the use of an interpreter, who was usually a relative. CONCLUSIONS: A significant number of patients presenting to A&E have difficulty in communicating in English. These consultations could often have been improved by the use of additional interpreter services. Telephone interpreter services may provide the answer for use in A&E departments because of their instant and 24 hour availability.  相似文献   
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Spectral measures have long been used to quantify the robustness of real-world graphs. For example, spectral radius (or the principal eigenvalue) is related to the effective spreading rates of dynamic processes (e.g., rumor, disease, information propagation) on graphs. Algebraic connectivity (or the Fiedler value), which is a lower bound on the node and edge connectivity of a graph, captures the “partitionability” of a graph into disjoint components. In this work we address the problem of modifying a given graph’s structure under a given budget so as to maximally improve its robustness, as quantified by spectral measures. We focus on modifications based on degree-preserving edge rewiring, such that the expected load (e.g., airport flight capacity) or physical/hardware requirement (e.g., count of ISP router traffic switches) of nodes remain unchanged. Different from a vast literature of measure-independent heuristic approaches, we propose an algorithm, called EdgeRewire, which optimizes a specific measure of interest directly. Notably, EdgeRewire is general to accommodate six different spectral measures. Experiments on real-world datasets from three different domains (Internet AS-level, P2P, and airport flights graphs) show the effectiveness of our approach, where EdgeRewire produces graphs with both (i) higher robustness, and (ii) higher attack-tolerance over several state-of-the-art methods.  相似文献   
17.
Research in the field of embodied music cognition has shown the importance of coupled processes of body activity (action) and multimodal representations of these actions (perception) in how music is processed. Technologies in the field of human–computer interaction (HCI) provide excellent means to intervene into, and extend, these coupled action-perception processes. In this article this model is applied to a concrete HCI application, called the “Conducting Master.” The application facilitates multiple users to interact in real time with the system in order to explore and learn how musical meter can be articulated into body movements (i.e., meter-mimicking gestures). Techniques are provided to model and automatically recognize these gestures in order to provide multimodal feedback streams back to the users. These techniques are based on template-based methods that allow approaching meter-mimicking gestures explicitly from a spatiotemporal account. To conclude, some concrete setups are presented in which the functionality of the Conducting Master was evaluated.  相似文献   
18.
The authors investigated the effects of gender on the social dynamics and outcomes of conversations involving 120 children (mean age = 8 years 7 months). Children were taught particular values for different shaped counters and placed in same-gender or mixed-gender pairs with children who were taught different values. Pairs were asked to add the counters together to make a total of 100. Conversations were coded in terms of communication acts and simultaneous speech acts. Boys used more controlling acts overall and more negative interruptions in mixed-gender pairs. Girls used more affiliating acts. All children used more collaborative communication in same-gender pairings. Children whose perspective dominated used more controlling and comparatively fewer affiliating acts. When children reached a compromise, conversations were more collaborative. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A tree-based method for the recognition of the tonal center or key in a musical audio signal is presented. Time-varying key feature vectors of 264 synthesized sounds are extracted from an auditory-based pitch model and converted into character strings using PCA-analysis and classification trees. The results are compared with distance-based methods. The characteristics of the new tonality analysis tool are illustrated on various examples. The potential of this method as a building stone in a music retrieval system is discussed.  相似文献   
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