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91.
Two experiments were conducted to examine the effects of cooking parameters, including final internal temperature (65, 72·5 or 80°C), on the eating quality of pork. Assessments were made by a 10-member trained taste panel. In Experiment 1 on loin steaks (m. longissimus) from 28 carcasses weighing 66 ± 1·9 (SD) kg, increasing the final internal temperature from 65 to 80°C had the following effects on mean scores (1-8): tenderness -1·0; juiciness -1·5, pork flavour +0·6 and abnormal flavour -0·5. The medium temperature of 72·5°C was suggested as ideal. In Experiment 2 on leg roasts (m. gluteobiceps) from 96 carcasses weighing 65 + 2·7 (SD) kg, increasing the final internal temperature from 65 to 80°C had the following effects on mean scores (1-8): tenderness -0·2 (not significant), juiciness -0·6, pork flavour +0·3 and abnormal flavour -0·5. The effects of final internal temperature were therefore smaller in roasts and temperatures towards the upper end of the range would be recommended for ideal eating quality, balancing small losses in tenderness and juiciness against gains in flavour scores. Although the experiments were not designed to examine source and sex effects there was evidence that tenderness can be improved through the use of Duroc genes and pelvic suspension of carcasses and no evidence of differences in eating quality between entire males and females.  相似文献   
92.
Soft robots adapt passively to complex environments due to their inherent compliance, allowing them to interact safely with fragile or irregular objects and traverse uneven terrain. The vast tunability and ubiquity of textiles has enabled new soft robotic capabilities, especially in the field of wearable robots, but existing textile processing techniques (e.g., cut-and-sew, thermal bonding) are limited in terms of rapid, additive, accessible, and waste-free manufacturing. While 3D knitting has the potential to address these limitations, an incomplete understanding of the impact of structure and material on knit-scale mechanical properties and macro-scale device performance has precluded the widespread adoption of knitted robots. In this work, the roles of knit structure and yarn material properties on textile mechanics spanning three regimes–unfolding, geometric rearrangement, and yarn stretching–are elucidated and shown to be tailorable across unique knit architectures and yarn materials. Based on this understanding, 3D knit soft actuators for extension, contraction, and bending are constructed. Combining these actuation primitives enables the monolithic fabrication of entire soft grippers and robots in a single-step additive manufacturing procedure suitable for a variety of applications. This approach represents a first step in seamlessly “printing” conformal, low-cost, customizable textile-based soft robots on-demand.  相似文献   
93.
    
We present our studies of the low-frequency excess electrical noise in YBa2Cu3O7- thin films in the normal state. We have studied films with varying microstructure deposited on different substrates. The frequency dependence and bias current dependence of the noise power spectral density agree with the behavior expected for noise due to conductance fluctuations. Comparison between films on different substrates shows that the presence of defects such as grain boundaries in the film correlate with significantly enhanced noise levels. The noise levels in our good-quality epitaxial films are several orders of magnitude lower than the anomalously large noise magnitudes reported for YBa2Cu3O7- in most of the earlier studies.  相似文献   
94.
Massively parallel processors have begun using commodity operating systems that support demand-paged virtual memory. To evaluate the utility of virtual memory, we measured the behavior of seven shared-memory parallel application programs on a simulated distributed-shared-memory machine. Our results (1) confirm the importance of gang CPU scheduling, (2) show that a page-faulting processor should spin rather than invoke a parallel context switch, (3) show that our parallel programs frequently touch most of their data, and (4) indicate that memory, not just CPUs, must be gang scheduled. Overall, our experiments demonstrate that demand paging has limited value on current parallel machines because of the applications' synchronization and memory reference patterns and the machines' high page-fault and parallel context-switch overheads.An earlier version of this paper was presented at Supercomputing '94.This work is supported in part by NSF Presidential Young Investigator Award CCR-9157366; NSF Grants MIP-9225097, CCR-9100968, and CDA-9024618; Office of Naval Research Grant N00014-89-J-1222; Department of Energy Grant DE-FG02-93ER25176; and donations from Thinking Machines Corporation, Xerox Corporation, and Digital Equipment Corporation.  相似文献   
95.
Birds are unrivaled windows into biotic processes at all levels and are proven indicators of ecological well-being. Understanding the determinants of species distributions and their dynamics is an important aspect of ecology and is critical for conservation and management. Through crowdsourcing, since 2002, the eBird project has been collecting bird observation records. These observations, together with local-scale environmental covariates such as climate, habitat, and vegetation phenology have been a valuable resource for a global community of educators, land managers, ornithologists, and conservation biologists. By associating environmental inputs with observed patterns of bird occurrence, predictive models have been developed that provide a statistical framework to harness available data for predicting species distributions and making inferences about species-habitat associations. Understanding these models, however, is challenging because they require scientists to quantify and compare multiscale spatialtemporal patterns. A large series of coordinated or sequential plots must be generated, individually programmed, and manually composed for analysis. This hampers the exploration and is a barrier to making the cross-species comparisons that are essential for coordinating conservation and extracting important ecological information. To address these limitations, as part of a collaboration among computer scientists, statisticians, biologists and ornithologists, we have developed BirdVis, an interactive visualization system that supports the analysis of spatio-temporal bird distribution models. BirdVis leverages visualization techniques and uses them in a novel way to better assist users in the exploration of interdependencies among model parameters. Furthermore, the system allows for comparative visualization through coordinated views, providing an intuitive interface to identify relevant correlations and patterns. We justify our design decisions and present case studies that show how BirdVis has helped scientists obtain new evidence for existing hypotheses, as well as formulate new hypotheses in their domain.  相似文献   
96.
The relationship between candidates' position on a ballot paper and vote rank is explored in the case of 5000 candidates for the UK 2010 local government elections in the Greater London area. This design study uses hierarchical spatially arranged graphics to represent two locations that affect candidates at very different scales: the geographical areas for which they seek election and the spatial location of their names on the ballot paper. This approach allows the effect of position bias to be assessed; that is, the degree to which the position of a candidate's name on the ballot paper influences the number of votes received by the candidate, and whether this varies geographically. Results show that position bias was significant enough to influence rank order of candidates, and in the case of many marginal electoral wards, to influence who was elected to government. Position bias was observed most strongly for Liberal Democrat candidates but present for all major political parties. Visual analysis of classification of candidate names by ethnicity suggests that this too had an effect on votes received by candidates, in some cases overcoming alphabetic name bias. The results found contradict some earlier research suggesting that alphabetic name bias was not sufficiently significant to affect electoral outcome and add new evidence for the geographic and ethnicity influences on voting behaviour. The visual approach proposed here can be applied to a wider range of electoral data and the patterns identified and hypotheses derived from them could have significant implications for the design of ballot papers and the conduct of fair elections.  相似文献   
97.
98.
We propose to replace a number of popular approximations by their diagonal quadratic Taylor series expansions. The resulting separable quadratic approximations are easily convexified, and are well suited for use in dual sequential approximate optimization (SAO) algorithms. Global convergence of the resulting SAO algorithms may be enforced in a natural way using conservatism. The approximated approximation approach is explicitly illustrated for (i) reciprocal and exponential intervening variables, (ii) the intervening variables used in the method of moving asymptotes (MMA), (iii) the intervening variables used in CONLIN, and (iv) the TANA-3 approximations. The use of intermediate responses for use in, for example, truss and frame-like structures, is also discussed. Key advantages of replacing nonlinear approximations by their diagonal quadratic approximations are that these approximated approximations can all be used simultaneously in a single dual statement; the dual does not depend on the form of the original approximations. In addition, in a dual setting, the resulting subproblems yield simple analytical relationships between the primal and dual variables, which is often not the case with the original nonlinear approximations. An important example hereof is the exponential approximation. Although the diagonal quadratic approximations may differ notably from their original counterparts, they typically are quite similar in a sufficiently small search subregion, which relates to the move limits commonly used in SAO anyway.  相似文献   
99.
Software development is a global activity unconstrained by the bounds of time and space. A major effect of this increasing scale and distribution is that the shared understanding that developers previously acquired by formal and informal face-to-face meetings is difficult to obtain. This paper proposes a shared awareness model that uses information gathered automatically from developer IDE interactions to make explicit orderings of tasks, artefacts and developers that are relevant to particular work contexts in collaborative, and potentially distributed, software development projects. The research findings suggest that such a model can be used to: identify entities (developers, tasks, artefacts) most associated with a particular work context in a software development project; identify relevance relationships amongst tasks, developers and artefacts e.g. which developers and artefacts are currently most relevant to a task or which developers have contributed to a task over time; and, can be used to identify potential bottlenecks in a project through a ‘social graph’ view. Furthermore, this awareness information is captured and provided as developers work in different locations and at different times.  相似文献   
100.
Despite the seeming ubiquity of young people's Internet use, there are still many for whom access to the Internet and online social networking remains inequitable and patterned by disadvantage. The connection between information technology and young people with disabilities is particularly under‐researched. This article contributes to the field of critical information systems research by exposing significant barriers and facilitators to Internet accessibility for young people with disabilities. It uses Bourdieu's critical theory to explore how the unequal distribution of resources shapes processes of digital inclusion for young people with disabilities. It highlights access needs and experiences that are both disability and non‐disability related. The article draws on interviews in South Australia with 18 young people aged 10–18 years with a physical disability (such as cerebral palsy) or acquired brain injury and with 17 of their family members. Interviews evaluated participants' and parents' reflections on the benefits of a home‐based, goal‐oriented intervention to increase the young person's Internet use for social participation purposes. The Bourdieuian analysis demonstrated how varying levels of accrued individual and family offline capital resources are related to digital/online resources and disability‐specific online resources. This revealed how unequal resources of capital can influence technology use and hence digital inclusion for young people with disabilities. Our study demonstrates that young people with particular types of disabilities require intensive, personalised and long‐term support from within and beyond the family to ‘get online’. We conclude that Internet studies need to more frequently adopt critical approaches to investigate the needs of users and barriers to information technology use within sub‐groups, such as young people with disabilities. © 2016 John Wiley & Sons Ltd  相似文献   
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