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排序方式: 共有439条查询结果,搜索用时 9 毫秒
1.
The change of foot length and width with age has been reported in a few anthropometric studies in the literature. However, the relationship with body height rarely is reported, and the dynamic effect of weightbearing on foot size has not been documented. In this series, 2829 children 3 to 18 years of age of equal gender distribution were included in the study. The foot length and width on weightbearing and nonweightbearing were measured with a special precision electronic caliper. The foot length and width were found to increase linearly from the age of 3 years until 12 years in girls and 15 years in boys. This was followed by a phase during which the increase plateaued. The foot length and width increased significantly on weightbearing at all ages in both genders with a mean of 2.1 to 4.4 mm or 3.1% to 4.8%, respectively. The foot length and width also were found to correlate significantly with the body height in both genders, with a correlation coefficient of 0.96 to 0.98. No significant differences were found between the sizes of the dominant and nondominant foot in either gender. 相似文献
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Mak B.K.-W. Tsz-Chung Lai Tsang I.W. Kwok J.T.-Y. 《IEEE transactions on audio, speech, and language processing》2009,17(7):1372-1381
This paper proposes a nonlinear generalization of the popular maximum-likelihood linear regression (MLLR) adaptation algorithm using kernel methods. The proposed method, called maximum penalized likelihood kernel regression adaptation (MPLKR), applies kernel regression with appropriate regularization to determine the affine model transform in a kernel-induced high-dimensional feature space. Although this is not the first attempt of applying kernel methods to conventional linear adaptation algorithms, unlike most of other kernelized adaptation methods such as kernel eigenvoice or kernel eigen-MLLR, MPLKR has the advantage that it is a convex optimization and its solution is always guaranteed to be globally optimal. In fact, the adapted Gaussian means can be obtained analytically by simply solving a system of linear equations. From the Bayesian perspective, MPLKR can also be considered as the kernel version of maximum a posteriori linear regression (MAPLR) adaptation. Supervised and unsupervised speaker adaptation using MPLKR were evaluated on the Resource Management and Wall Street Journal 5K tasks, respectively, achieving a word error rate reduction of 23.6% and 15.5% respectively over the speaker-independently model. 相似文献
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Bernardo Cordovez Aram J. Chung Michael Mak David Erickson 《Microfluidics and nanofluidics》2011,10(4):785-791
In this article, we explore a new fabrication process for a flexible, all polymer, active fluidic delivery system, incorporating
a fusion of laser micromachining and microfabrication techniques as well as rapid prototyping technology. Here, we show selective
fluidic delivery from isolated microchannels through an electrochemically driven pumping reaction, demonstrate the dispensing
of dose volumes up to 5.5 μl, and evaluate the device’s performance in terms of its delivery speed and ejection efficiency.
Finally, we move this work toward an implantable microfluidic drug delivery device by investigating the device’s biocompatibility
through a statistical approach that overviews the viability of bovine aortic endothelial cells on polyimide and silicon substrates. 相似文献
5.
Engineering changes (ECs) are changes and/or modifications in forms, fits, functions, materials, dimensions, etc., of products and constituent components. ECs usually induce a series of downstream changes. Multiple disciplines and responsibilities are therefore involved in managing ECs. Previous investigations conducted by the authors and other researchers have shown that paper-based and standalone computerised EC management (ECM) systems have limited support for such intensive teamwork and close communication. This paper proposes to establish a web-based framework that supports ECM procedures and activities. A web-based ECM system is able to provide better information sharing, simultaneous data access and processing and more prompt communication and feedback. The amount of paperwork and the throughput time of managing ECs are significantly reduced while the effectiveness and the efficiency are substantially improved. This paper focuses on discussing the issues of design, development, and implementation of this prototype web-based ECM system. 相似文献
6.
Rule induction is an important part of learning in expert systems. Rules can help managers make more effective decisions and gain insight into the relationships between decision variables. We present a logic-based approach to rule induction in expert systems which is simple, robust and consistent. We also derive bounds on levels of certainty for combining rules. We apply our approach to the development of rules for the entry decisions of new products. We then discuss how the logic-based approach of rule induction can be used to create a decision support system and the methodology to create such a system. 相似文献
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D. Rossi M. Omaña J. M. Cazeaux C. Metra T. M. Mak 《Journal of Electronic Testing》2014,30(1):111-123
In this paper, we show that clock faults producing duty-cycle variations, which have been proven very likely, can give rise to min or max delay violations. This mandates new, specific testing approaches for clock faults, to avoid them to compromise the system correct operation in the field, with dramatic effects on product quality and defect level. We then introduce a new scheme that can be employed to detect the clock faults causing duty-cycle variations. 相似文献
10.
Mak A.C.K. Rowell C.R. Murch R.D. Chi-Lun Mak 《Antennas and Propagation, IEEE Transactions on》2007,55(7):1919-1928
New designs for compact reconfigurable antennas are introduced for mobile communication devices. The uniqueness of the antenna designs are that they allow various groups of their operating frequency bands to be selected electronically. In particular, each group of frequency bands, or mode, can be made to serve several different communication systems simultaneously. These systems may include various combinations of GSM, DCS, PCS, UMTS, Bluetooth, and wireless local-area network (LAN). Therefore, by electronically selecting different antenna modes, a variety of communication systems can be conveniently served by only one antenna. One advantage is that through the different operational modes, the total antenna volume can be reused, and therefore the overall antenna can be made compact. In these designs, the selection of the different modes is achieved by either i) switching different feeding locations of the antenna (switched feed) or ii) switching or breaking of the antenna's connection to the ground (switched ground). This paper demonstrates these two designs. For the first design of switched feed, it can support GSM, DCS, PCS, and UMTS. In the second design, the antenna makes use of a switched-ground technique, which can cover GSM, DCS, PCS, UMTS, Bluetooth, and 2.4 GHz wireless LAN. The designs are investigated when ideal switches and also various realistic active switches based on PIN diodes, GaAs field effect transistor, and MEMs configurations. The designs are verified through both numerical simulations and measurement of an experimental prototype. The results confirm good performance of the two multiband reconfigurable antenna designs. 相似文献