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81.
Perfect fit for people has always been a target for product design. Designers commonly use traditional anthropometric dimensions for 3D product design thus creating a lot of fitting problems when dealing with the complexities of human body shapes. The development of recent 3D anthropometric survey has created an opportunity for complex shape analysis on human model by collecting 3D scan data. Using 3D point cloud data from the SizeChina survey, a methodology of creating a homologous 3D head and face model was demonstrated in this study. Anatomical and virtual landmarks, and surface modeling algorithm based on point cloud data were applied in building the model. The head and face models for all scans had the same amount of vertices with consistent features. The average Chinese models showed obvious differences between male and female. The variations of head and face shapes were analyzed using Principal Component Analysis and the results showed that the largest variations among people were general size, especially for width and depth. However face height, forehead, back of the head, chin and jaw area were also important when describing the 3D shape. The results from this study may be useful in the design of head and facial products. 相似文献
82.
One of the many complex problems that arise from the transmission and marketing of natural gas is when a shipper draws a contract
with a pipeline company to deliver a certain amount of gas among several points. What is actually delivered is often different
from the amount that had been originally agreed upon. This phenomenon is called an imbalance. When an imbalance occurs, the pipeline penalizes the shipper by imposing a cash-out penalty policy. Since this penalty is
a function of the operating daily imbalances, an important decision-making problem for the shippers is how to carry out their
daily imbalances so as to minimize their incurred penalty.
In this paper, we introduce the problem of minimizing the cash-out penalty costs from the point of view of a natural gas shipping
party. We present a mixed integer bilevel linear programming model and discuss its underlying assumptions. To solve it efficiently,
we reformulate it as a standard mathematical program and describe a penalty-function algorithm functions for its solution.
The algorithm is well-founded and its convergence is proved. Results of numerical experiments support the algorithm’s robustness
providing a valuable solution technique for this very important and complex problem in the natural gas market. 相似文献
83.
Fault and attack management in all-optical networks 总被引:2,自引:0,他引:2
Ridha Rejeb Mark S. Leeson Roger J. Green 《Communications Magazine, IEEE》2006,44(11):79-86
Network management for optical networks faces additional security challenges that arise by using transparent optical network components in communication systems. While some available management mechanisms are applicable to different types of network architectures, many of these are not adequate for all-optical networks. These have unique features and requirements in terms of security and quality of service, thus requiring a much more targeted approach in terms of network management. In this article we consider management issues with particular emphasis on complications that arise due to the unique characteristics and peculiar behaviors of transparent network components. In particular, signal quality monitoring is still a major complication in all-optical networks. Despite new methods for detection and localization of attacks having been proposed, no robust standards or techniques exist to date for guaranteeing the quality of service in these networks. Therefore, sophisticated mechanisms that assist in managing and assessing the proper function of transparent network components are highly desirable. Accordingly, we present an algorithm for multiple attack localization and identification that can participate in some tasks for fault management of all-optical networks 相似文献
84.
在过去的几年中,国际放射防护委员会鼓励对其计划将于2005年发表的下一个建议书表述辐射防护理念的最佳方式开展讨论。现在的建议书是由1990年发表的第60号出版物提出的,而且得到过去12年里发表的其它出版物的补充。现在显然委员会有必要总结在大约10个报告中推荐的数值数量的完整性。本文将完成这项工作,并由此而表明前进方向,提出一个简明且比较一致的21世纪初防护理念的表述。当然并不意在进行根本的修改,而是建议对现行政策做出连贯一致的表述,对其应用进行简化。 相似文献
85.
A. A. Zhukov E. T. Filby A. V. Goncharov M. A. Ghanem P. N. Bartlett R. Boardman H. Fangohr V. V. Metlushko V. Novosad G. Karapetrov P. A. J. de Groot 《Journal of Low Temperature Physics》2005,139(1-2):339-349
Using self-assembly from colloidal suspensions of polystyrene latex spheres we prepared well-ordered templates. By electrochemical
deposition of magnetic and superconducting metals in the pores of such templates highly ordered magnetic and superconducting
anti-dot nano-structures with 3D architectures were created. Further developments of this template preparation method allow
us to obtain dot arrays and even more complicated structures. In magnetic anti-dot arrays we observe a large increase in coercive
field produced by nanoscale (50–1000nm) holes. We also find the coercive field to demonstrate an oscillatory dependence on
film thickness. In magnetic dot arrays we have explored the genesis of 3D magnetic vortices and determined the critical dot
size. Superconducting Pb anti-dot arrays show pronounced Little-Parks oscillations in Tc and matching effects in magnetization and magnetic susceptibility. The spherical shape of the holes results in significantly
reduced pinning strength as compared to standard lithographic samples. Our results demonstrate that self-assembly template
methods are emerging as a viable, low cost route to prepare sub-micron structures. 相似文献
86.
For small, portable devices, speech input has the advantages of low-cost and small hardware, can be used on the move or whilst
the eyes & hands are busy, and is natural and quick. Rather than rely on imperfect speech recognition we propose that information
entered as speech is kept as speech and suitable tools are provided to allow quick and easy access to the speech-as-data records.
This paper summarises our work on the technologies needed for these tools – for organising, browsing, searching and compressing
the stored speech. These technologies go a long way towards giving stored speech the characteristics of text without the associated
input problems.
Received: 5 March 2002 / Accepted: 1 September 2002
Nick Haddock Consultant
Acknowledgements The authors would like to thank the whole HP Labs Gryphon team for their valuable contributions to this work - Mike Collins
for the hierarchical chunking algorithm, Erik Geelhoed and David Frohlich for the users perspective, Richard Hull for starting
off the compression work, Steve Loughran for productisation, and Dave Reynolds for his consistent advice and support. We would
also like to thank our partners at Cambridge University, Steve Young and Tony Robinson, whose expertise and technology formed
the foundation for this work, as well as the efforts of Kate Knill on wordspotting, Carl Seymour on compression, James Christie
on recognition, and Robin Valenza whose brief excursion into the world of speech technology helped develop a simple and effective
summarisation technique. Finally we would like to thank the reviewers for their many helpful comments. 相似文献
87.
Preparation and characterisation of titanium dioxide films for catalytic applications generated by anodic spark deposition 总被引:1,自引:0,他引:1
The advanced plasma electrochemical process of anodic spark deposition (ASD) was used to generate photoactive titanium dioxide films on titanium metal substrates. A shift to easier-to-machine substrates was demonstrated by the deposition of a titanium film with physical vapour deposition onto different materials such as glass, silicon, and stainless steel prior to ASD. Obtained films were characterised by scanning electron microscopy, surface area measurement (Brunnauer-Emmett-Teller method, BET), X-ray diffraction, electron-probe microanalysis, and glow discharge spectroscopy. Additionally, film thickness was determined by eddy current measurements. Standard ASD conditions were defined as 180 V applied voltage over a 180 s hold time, a voltage ramp of 20 V/s, a duty cycle of 0.5 and a frequency of 1500 Hz. Most prominent characteristics of the titanium films produced under these standard conditions are a film thickness of ≤80 μm, a surface area of approximately 51 m2/g (BET) and an anatase content of approximately 30% and rutile content of approximately 70%. Furthermore, the film formation process is elucidated and the dependence of film thickness on deposition time and the dependence of the anatase and rutile content on the deposited mass are shown for varying ASD conditions. 相似文献
88.
Ratcliff Roger; Thapar Anjali; Gomez Pablo; McKoon Gail 《Canadian Metallurgical Quarterly》2004,19(2):278
The effects of aging on response time (RT) are examined in 2 lexical-decision experiments with young and older subjects (age 60-75). The results show that the older subjects were slower than the young subjects, but more accurate. R. Ratcliff s (1978) diffusion model provided a good account of RTs, their distributions, and response accuracy. The fits show an 80-100-ms slowing of the nondecision components of RT for older subjects relative to young subjects and more conservative decision criterion settings for older subjects than for young subjects. The rates of accumulation of evidence were not significantly different for older compared with young subjects (less than 2% and 5% higher for older subjects relative to young subjects in the 2 experiments). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Oliver Matthew N. I.; Bernstein Jessey H.; Anderson Kristen G.; Blashfield Roger K.; Roberts Michael C. 《Canadian Metallurgical Quarterly》2004,35(2):141
Do psychology students view their training programs as doing enough to appropriately identify, accommodate, and possibly dismiss students who manifest significant impairment? This study reports the general findings of an exploratory survey distributed to clinical psychology graduate students. Overall, students viewed impairment as a highly sensitive and inadequately addressed issue. Students commonly reported frustration with and concern for impaired colleagues. A few respondents indicated that the terms impaired and problem student were insensitive and that greater attention needed to be given to "impaired" training contexts. Implications regarding formal standards for interpersonal functioning and programmatic supports for students are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Roger Levenhagen 《Network Security》2004,2004(1):13-15
A shortlist of the most memorable events of 2003 will undoubtedly include the demise of Saddam Hussein's regime but what will surely be omitted from most top 10s is the continuing threat posed by malware — viruses and other malicious code – and the nuisance of spam messaging. These omissions are made despite worrying developments in mass mail worms, blended threats and increasing spam complexity. 相似文献