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61.
A. S. Macdonald D. Loudon P. J. Rowe D. Samuel V. Hood A. C. Nicol M. A. Grealy B. A. Conway 《Universal Access in the Information Society》2007,6(2):137-144
This paper discusses the development of a design tool using data calculated from the biomechanical functional demand on joints
in older adults during activities of daily living, portrayed using a visual ‘traffic-light’ system. Whole body movements of
84 older adults were analysed using a 3D motion capture system and reaction forces were measured by force platforms, and translated
into a 3D software model. Although originally intended as a tool for designers, the early evaluation of this method of visualizing
the data suggests that it may be of value across those involved in the professional care of older adults. 相似文献
62.
Clark Stephen Hood Nick Birkin Mark 《Journal of Housing and the Built Environment》2022,37(3):1489-1509
Journal of Housing and the Built Environment - This study extends our understanding of the influence of proximity to retail grocery provision on housing rental prices. To achieve this, extensive... 相似文献
63.
The presence of a partial break, in which some strands of a fibre assembly break but the remaining ones continue to be wound, can be critical when the strength of the end-product affects safety. Such breaks are difficult to detect during production, particularly in high-speed winding, and fatally flawed material can easily be produced. Conventional electronic apparatus is ineffective, as a result of noise, drift, and stray capacitance, in detecting partial breaks, so a new technique involving pulse circuitry was developed. The usual problems were avoided by carrying out measurements in the time domain, rather than measurements of analogue electrical phenomona, and relating these measurements to the mass instantaneously present between detecting electrodes. By these means, excellent monitoring in a difficult situation was achieved, no undetected partial breaks or spurious alarms being observed. For test purposes, severe conditions were deliberately chosen, and control limits of ± 12.5% had to be accepted, but conventional situations are expected to be capable of much finer control. The principle of operation can be extended to a variety of situations and is potentially useful in many other textile applications, such as carding, combing, drafting, and other operations where a weak strand of fibrous material with little or no twist must be manipulated. 相似文献
64.
Aramandla Ramesh Darryl B. Hood Frank Inyang Michael Greenwood Alfred M. Nyanda Anthony E. Archibong 《Polycyclic Aromatic Compounds》2013,33(3-4):969-980
The metabolic fate of high doses of B a P is not fully established. To fill this important data need, a comprehensive metabolism, bioavailability, and toxicokinetic study has been undertaken to track the fate of B a P subsequent to single acute exposures. Doses of 100 mg/kg body weight, 0.1 mg/m 3 (equivalent to 19 mg/kg oral dose), and 4.5 w g/kg B a P were administered to 8-week-old male F-344 rats via oral, inhalation (nose only), and intravenous routes, respectively. Rats were sacrificed at 0, 0.5, 1, 2, 4, 6, 24, 48, and 72 hr postexposure. Blood, liver, lung, brain, reproductive tissues, urine, and feces samples were analyzed for parent B a P and metabolites by HPLC with fluorescence detection. Most of the administered B a P was metabolized 4, 6, and 72 hr postexposure for inhalation, intravenous, and oral routes, respectively. The following metabolites were detected: 4,5-dihydrodiol, 7,8-dihydrodiol, 9,10-dihydrodiol, 3,6-dione, 3-hydroxy, and 9-hydroxy B a P (organic fraction), glucuronides, sulfates, and glutathione conjugates (aqueous fraction). Toxicokinetic data revealed a high mean residence time, and low clearance values for B a P metabolites in lung, liver, and brain relative to plasma. Findings of this study establish the relationship between bioavailability and the acute toxic effects of B a P observed in our laboratory at these high doses. 相似文献
65.
Segmented polyurethanes (SPUs) have been designed with controlled hard to soft segment ratios. The confinement effect of the SPU blocks is induced by phase separation of the SPU segments and has been harnessed to selectively control crystallization. Hard segment (HS) concentrations greater than 50 wt.% allowed for the study of morphological changes and mechanical properties associated with confinement of the soft segment (SS). It was observed that crystallization temperature and normalized percent crystallinity were reduced with increasing HS content, creating a largely amorphous PEG SS at ambient temperature. High temperature annealing further confined the SS because the HS had more time to crystallize, which increased confinement. Considerable insight has been gained through the manipulation and characterization of the SS and HS, in an SPU, towards the design of impact absorbing and structural materials. 相似文献
66.
67.
The rapid advances in proteomic technologies have made possible systematic analysis of hundreds to thousands of proteins in clinical samples with the promise of uncovering novel protein biomarkers for various disease conditions. We will discuss in this review article current MS and protein chip-based quantitative proteomic approaches and their application in biomarker discovery. The emphasis will be placed on new quantification strategies employing stable isotopic labeling coupled with MS/MS, and antibody-based protein chips and nanodevices. The strength and weakness of each technology are briefly highlighted. 相似文献
68.
The traditional approach to modeling of internet worm propagation is to adopt a mathematical model, usually inspired by modeling
of the spread of infectious diseases, describing the expected number of hosts infected as a function of the time since the
start of infection. The predictions of such a model are then used to evaluate, improve, or develop defense and containment
strategies against worms. However, a proper and complete understanding of worm propagation goes well beyond the mathematical
formula given by the chosen model for the expected number of hosts infected at a given time. Thus, questions such as fitting
the model, assessing the extent to which a specific realization of a worm spread may differ from the model’s predictions,
behavior of the time points at which infections occur, and the estimation and effects of misspecification of model’s parameters
must also be considered. In this paper, we address such questions for the well-known random constant spread (RCS) model of
worm propagation. We first generalize the RCS model to our nonhomogeneous random scanning (NHRS) model. The NHRS model allows
the worm’s contact rate to vary during worm propagation and it thus captures far more situations of interest than the RCS
model which assumes a scanning rate constant in time. We consider the problem of fitting these models to empirical data and
give a simulation procedure for a RCS epidemic. We also show how to obtain a confidence interval for the unknown contact rate
in the RCS model. In addition, the use of prior information about the contact rate is discussed. The results and methodologies
of this paper illuminate the structure and application of NHRS and RCS models of worm propagation. 相似文献
69.
Generally, real-time applications based on the User Datagram Protocol (UDP) generate large volumes of data and are not sensitive to network congestion. In contrast, Transmission Control Protocol (TCP) traffic is considered "well-behaved" because it prevents the network becoming congested by means of closed-loop control of packet-loss and round-trip-time. The integration of both sorts of traffic is a complex problem, and depends on solutions such as admission control that have not yet been deployed on the Internet. Moreover, the problem of quality-of-service (QoS) and resource allocation is extremely relevant from the point of view of convergence of streaming media and data transmission on the Internet. In this paper an adaptive real-time protocol based on the least mean square (LMS) algorithm is proposed to estimate the application UDP bandwidth in order to reduce the quadratic error between the packet loss and a target. Moreover, the LMS algorithm is also applied to make sure that the reduction in the average bandwidth allocated to each TCP process will not be higher than a given percentage of the average bandwidth allocated before the beginning of the UDP application. 相似文献
70.
We describe a system that simplifies the process of debugging programs produced by computer-aided parallelization tools. The system uses relative debugging techniques to compare serial and parallel executions in order to show where the computations begin to differ. If the original serial code is correct, errors due to parallelization will be isolated by the comparison.One of the primary goals of the system is to minimize the effort required of the user. To that end, the debugging system uses information produced by the parallelization tool to drive the comparison process. In particular, the debugging system relies on the parallelization tool to provide information about where variables may have been modified and how arrays are distributed across multiple processes. User effort is also reduced through the use of dynamic instrumentation. This allows us to modify the program execution without changing the way the user builds the executable. The use of dynamic instrumentation also permits us to compare the executions in a fine-grained fashion and only involve the debugger when a difference has been detected. This reduces the overhead of executing instrumentation. 相似文献