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991.
Siefert Caleb J.; Kehl-Fie Kendra; Blais Mark A.; Chriki Lyvia 《Canadian Metallurgical Quarterly》2007,19(4):469
The present studies focus on strategies for detecting back irrelevant responding (BIR) on the Personality Assessment Inventory (PAI; L. C. Morey, 1991). Moderate BIR levels can greatly affect the clinical scales of the PAI. Further, the PAI's Inconsistency and Infrequency validity scales are less than optimal for detecting BIR. L. C. Morey and C. J. Hopwood (2004) developed an alternative strategy for detecting BIR that involves comparison of 2 scales from the PAI short-form with the same 2 scales from the PAI full-instrument. The present study examines how different BIR levels affect the clinical, treatment, and interpersonal scales of the PAI in 2 psychiatric inpatient samples. The effectiveness of various strategies for detecting BIR in an inpatient setting is also discussed. Consistent with previous research, moderate rates of BIR impacted several PAI scales in a meaningful way. The Inconsistency and Infrequency validity scales of the PAI were relatively ineffective for detecting low-to-moderate BIR levels. Conversely, the short-form full-instrument comparison strategy was much more sensitive to BIR. Finally, a new BIR detection indicator is presented that improves sensitivity rates for detecting all BIR levels in an acute setting. The implications of these results for detecting BIR in inpatient settings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Harrison Emily L. R.; Marczinski Cecile A.; Fillmore Mark T. 《Canadian Metallurgical Quarterly》2007,15(6):588
[Correction Notice: An erratum for this article was reported in Vol 16(2) of Experimental and Clinical Psychopharmacology (see record 2008-03846-009). The correct title of the article should read "Driver training conditions affect sensitivity to the impairing effects of alcohol on a simulated driving test".] Research shows that prior behavioral training in a challenging environment reduces alcohol-induced impairment on simple psychomotor tasks. However, no studies have examined if this relationship generalizes to driving performance. The present study examined simulated driving performance and tested the hypothesis that a challenging training history would protect against the impairing effects of alcohol on driving performance. The challenging training history involved driving in a visually-impoverished environment. Thirty adults were randomly assigned to one of three groups. Two groups were tested under alcohol (0.65 g/kg) after prior experience performing the task under either a visually-impoverished environment or a normal visual environment. The remaining group served as a control and was trained and tested under the visually-impoverished condition environment. Results showed that individuals trained in the impoverished environment displayed sober levels of performance when their performance was subsequently tested under alcohol. By contrast, volunteers trained in a normal environment showed impairment under alcohol. The findings suggest that differences in driving training history can affect a driver's sensitivity to the impairing effects of alcohol. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
A review of machining theory and tool wear with a view to developing micro and nano machining processes 总被引:5,自引:0,他引:5
Grant Mark Robinson Mark James Jackson Michael D. Whitfield 《Journal of Materials Science》2007,42(6):2002-2015
This paper reviews the current state-of-the-art surrounding macro scale machining; it discusses how these factors will influence
the future development of micro and nano scale machining. The paper begins by reviewing machining theory, and then discusses
high speed machining, tool wear, tool coatings, micromachining, meso machine tool design and future applications and research
directions. Tool wear is a factor that determines the economy of the machining process. Therefore, an extensive part of the
paper is devoted to the development of materials used to coat tools; in turn, it is anticipated these coatings will used in
future micro machining applications. Consideration is also given to machine structures that are required to use these cutting
tools at speeds in excess of one million revolutions per minute. This review provides a timely explanation of the literature
surrounding the factors required for successful micro and nano machining. 相似文献
994.
Mark Thoren 《电子设计技术》2007,14(9):110-111
模拟或混合信号实验室中不能有太多的电压源.简单合适的高精度电压源可在一个运算放大器电路中设定偏置点、通过一个大电阻调整电源的反馈节点,或对ADC进行快速的线性测试.工程师们经常使用直流电源,因为这是他们能找到的唯一电源.许多实验室中缺乏真正的电压校准源.本设计实例描述了重复利用原有的精密电位器的电路.这种电位器能直接读取刻度,并能装到实验室电压箱中. 相似文献
995.
In a mobile ad hoc network (MANET), the nodes act both as traffic sources and as relays that forward packets from other nodes along multi-hop routes to the destination. Such networks are suited to situations in which a wireless infrastructure is unavailable, infeasible, or prohibitively expensive. However, the lack of a secure, trusted infrastructure in such networks make secure and reliable packet delivery very challenging. A given node acting as a relay may exhibit Byzantine behavior with respect to packet forwarding, i.e., arbitrary, deviant behavior, which disrupts packet transmission in the network. For example, a Byzantine node may arbitrarily choose to drop or misroute a certain percentage of the packets that are passed to it for forwarding to the next hop. In earlier work, we proposed a trust establishment framework, called Hermes, which enables a given node to determine the “trustworthiness” of other nodes with respect to reliable packet delivery by combining first-hand trust information obtained independently of other nodes and second-hand trust information obtained via recommendations from other nodes. A deficiency of the Hermes scheme is that a node can fail to detect certain types of Byzantine behavior, such as packet misforwarding directed at a particular source node. In this paper, we propose new mechanisms to make Hermes robust to Byzantine behavior and introduce a punishment policy that discourages selfish node behavior. We present simulation results that demonstrate the effectiveness of the proposed scheme in a variety of scenarios involving Byzantine nodes that are malicious both with respect to packet forwarding and trust propagation. 相似文献
996.
Graham Brooker Ross Hennessey Craig Lobsey Mark Bishop Eleonora Widzyk‐Capehart 《野外机器人技术杂志》2007,24(7):527-557
This paper defines the issues required for the development of successful visualization sensors for use in open cut and underground mines. It examines the mine environment and considers both the reflectivity of the rock and attenuation effects of dust and water droplets. Millimeter wave technology, as an alternative to the more commonly used laser and sonar implementations, is selected due to its superior penetration through adverse atmospheric conditions. Of the available radar techniques, frequency modulated continuous wave (FMCW) is selected as being the most robust. The theoretical performance of a number of 77 and 94 GHz FMCW millimeter wave radar systems is determined and these confirm the capability of these sensors in the mining environment. Implementations of FMCW radar sensors for simple ranging and three‐dimensional surface profiling are discussed before data obtained during field trials in mines is presented to justify the selection of this technology. © 2007 Wiley Periodicals, Inc. 相似文献
997.
Mark Aston 《Journal of the Society for Information Display》2007,15(8):535-540
Abstract— In recent years, the majority of R&D for large‐area displays has been to serve the production of large monolithic substrate technology such as plasma‐display panels (PDPs) and TFT‐LCD. While the pursuit of large displays for domestic and light‐industrial use benefits from the production of these high‐quality high‐pixel‐count technologies, there is still a need to produce displays in formats other than 4:3 or 16:9 and on a larger scale than currently available in single‐substrate displays. The options that exist for producing tiled displays from emerging technologies is examined and a practical technique for creating large‐area (1.8 × 1.2 m and larger) monochrome or color displays from tiling smaller units is discussed. This presents a cost‐effective approach for arranging small tiles to create a much larger screen and offers a simple way to address the market gap between large monolithic displays and small conventional LED video‐wall displays, in the size range of 1–10‐mm pixels for advertising and industrial use. By examining the requirements for pixel size and pitch against the range of viewing distances commonly associated with the target markets for these displays, it will be shown that complex manufacturing is not always required. 相似文献
998.
Lei Sun Evor L. Hines Roger J. Green Mark S. Leeson D. Daciana Iliescu 《国际射频与微波计算机辅助工程杂志》2007,17(5):493-504
This article illustrates a microwave dielectric lens design using genetic programming (GP), which, to the best knowledge of the authors, is the first time GP has been applied to design a microwave dielectric lens. A phase‐compensating single layer lens and a quarter‐wave phase‐compensating multilayer dielectric lens, which uses four types of materials and a zoned structure, was designed using GP. The dielectric lens shape was designed using GP strategy, with a random initial shape, to compensate for the phase error of the multilayer dielectric lens and to achieve the required performance. Standard GP (SGP) and hierarchical fair competition genetic programming (HFC‐GP) was applied to obtain the solution. The results show that this novel method of microwave lens shape design using GP is both accurate and stable. In addition, the simulation results of using high frequency simulation software (HFSS) are illustrated and compared. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. 相似文献
999.
This paper addresses content-based image retrieval in general, and in particular, focuses on developing a hidden semantic concept discovery methodology to address effective semantics-intensive image retrieval. In our approach, each image in the database is segmented into regions associated with homogenous color, texture, and shape features. By exploiting regional statistical information in each image and employing a vector quantization method, a uniform and sparse region-based representation is achieved. With this representation, a probabilistic model based on statistical-hidden-class assumptions of the image database is obtained, to which the expectation-maximization technique is applied to analyze semantic concepts hidden in the database. An elaborated retrieval algorithm is designed to support the probabilistic model. The semantic similarity is measured through integrating the posterior probabilities of the transformed query image, as well as a constructed negative example, to the discovered semantic concepts. The proposed approach has a solid statistical foundation; the experimental evaluations on a database of 10000 general-purposed images demonstrate its promise and effectiveness. 相似文献
1000.
Mark Shaw Venkatesh Meda Lope Tabil Anthony Opoku 《The Journal of microwave power and electromagnetic energy》2007,41(2):59-68
Heat sensitive properties (aromatic, medicinal, color) provide herbs and spices with their high market value. In order to prevent extreme loss of heat sensitive properties when drying herbs, they are normally dried at low temperatures for longer periods of time to preserve these sensory properties. High energy consumption often results from drying herbs over a long period. Coriander (Coriandrum sativum L., Umbelliferae) was dehydrated in two different drying units (thin layer convection and microwave dryers) in order to compare the drying and final product quality (color) characteristics. Microwave drying of the coriander foliage was faster than convective drying. The entire drying process took place in the falling rate period for both microwave and convective dried samples. The drying rate for the microwave dried samples ranged from 42.3 to 48.2% db/min and that of the convective dried samples ranged from 7.1 to 12.5% db/min. The fresh sample color had the lowest L value at 26.83 with higher L values for all dried samples. The results show that convective thin layer dried coriander samples exhibited a significantly greater color change than microwave dried coriander samples. The color change index values for the microwave dried samples ranged from 2.67 to 3.27 and that of the convective dried samples varied from 4.59 to 6.58. 相似文献