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991.
Larson Christine L.; Nitschke Jack B.; Davidson Richard J. 《Canadian Metallurgical Quarterly》2007,7(1):182
The authors examined the time course of affective responding associated with different affective dimensions--anxious apprehension, anxious arousal, and anhedonic depression--using an emotion-modulated startle paradigm. Participants high on 1 of these 3 dimensions and nonsymptomatic control participants viewed a series of affective pictures with acoustic startle probes presented before, during, and after the stimuli. All groups exhibited startle potentiation during unpleasant pictures and in anticipation of both pleasant and unpleasant pictures. Compared with control participants, symptomatic participants exhibited sustained potentiation following the offset of unpleasant stimuli and a lack of blink attenuation during and following pleasant stimuli. Common and unique patterns of affective responses in the 3 types of mood symptoms are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
The widespread implementation of systems of care represents an important opportunity to integrate behavioral, cognitive, milieu, client-centered, group, solution-focused, systems, multicultural, and ecological approaches to child and family therapy. This integrated approach is described and illustrated, and systems of care principles are considered to be a useful foundation for effective therapeutic practices for difficult problems of children, families, and adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Taylor Steven; Zvolensky Michael J.; Cox Brian J.; Deacon Brett; Heimberg Richard G.; Ledley Deborah Roth; Abramowitz Jonathan S.; Holaway Robert M.; Sandin Bonifacio; Stewart Sherry H.; Coles Meredith; Eng Winnie; Daly Erin S.; Arrindell Willem A.; Bouvard Martine; Cardenas Samuel Jurado 《Canadian Metallurgical Quarterly》2007,19(2):176
Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n = 2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n = 4,494) and a clinical sample from the United States and Canada (n = 390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Wayne M. Cranton Sharron L. Wilson Demosthenes C. Koutsogeorgis Richard Hedgley Stephen Lipiec 《Thin solid films》2007,515(24):8534-8538
The feasibility of low-temperature fabrication of transparent electrode elements from thin films of antimony-doped tin oxide (SnO2:Sb, ATO) has been investigated via inkjet printing, rf magnetron sputtering and post-deposition excimer laser processing. Laser processing of thin films on both glass and plastic substrates was performed using a Lambda Physik 305i excimer laser, with fluences in the range 20-100 mJ cm− 2 reducing sheet resistance from as-deposited values by up to 3 orders of magnitude. This is consistent with TEM analysis of the films that shows a densification of the upper 200 nm of laser-processed regions. 相似文献
995.
Hyundai Park Alexander W. Fang Oded Cohen Richard Jones Mario J. Paniccia John E. Bowers 《Photonics Technology Letters, IEEE》2007,19(4):230-232
We report a hybrid AlGaInAs-silicon evanescent amplifier incorporating a silicon waveguide with a III-V gain medium. The optical mode of the hybrid amplifier is mostly confined to the silicon waveguide and evanescently coupled to the AlGaInAs quantum-well (QW) region where optical gain is provided by electrical current injection. These two different material systems are bonded by low-temperature oxygen plasma assisted wafer bonding at 300 degC. The fabricated device shows 13 dB of maximum chip gain with 11 dBm of output saturation power. Evanescent coupling allows a lower active region confinement factor to provide a higher saturation output power than amplifiers with centered QWs, which is important for applications that require linear amplification 相似文献
996.
Haroldo Takashi Hattori Ian McKerracher Hark Hoe Tan Chennupati Jagadish Richard Michael De La Rue 《Quantum Electronics, IEEE Journal of》2007,43(4):279-286
In this paper, we analyze the coupling of light from photonic-crystal band-edge lasers into single-mode waveguides. Both active and passive devices lie in the same plane and coupling of light is achieved by using parabolic and nanotapers in InP based epitaxial structures. Two- and three-dimensional finite-difference time-domain methods are employed to analyze these devices. Coupling efficiencies higher than 80% can be obtained with parabolic couplers. We also present laser configurations that can reduce multiwavelength coupling of light into single-mode waveguides, using structures that are similar to coupled cavity Fabry-Peacuterot lasers 相似文献
997.
Sachin Joshi Sagnik Dey Michelle Chaumont Alan Campion Sanjay K. Banerjee 《Journal of Electronic Materials》2007,36(6):641-647
We demonstrate ultra-thin (<150 nm) Si1−x
Ge
x
dislocation blocking layers on Si substrates used for the fabrication of tensile-strained Si N channel metal oxide semiconductor
(NMOS) and Ge P channel metal oxide semiconductor (PMOS) devices. These layers were grown using ultra high vacuum chemical
vapor deposition (UHVCVD). The Ge mole fraction was varied in rapid, but distinct steps during the epitaxial layer growth.
This results in several Si1−x
Ge
x
interfaces in the epitaxially grown material with significant strain fields at these interfaces. The strain fields enable
a dislocation blocking mechanism at the Si1−x
Ge
x
interfaces on which we were able to deposit very smooth, atomically flat, tensile-strained Si and relaxed Ge layers for the
fabrication of high mobility N and P channel metal oxide semiconductor (MOS) devices, respectively. Both N and P channel metal
oxide semiconductor field effect transister (MOSFETs) were successfully fabricated using high-k dielectric and metal gates
on these layers, demonstrating that this technique of using ultra-thin dislocation blocking layers might be ideal for incorporating
high mobility channel materials in a conventional CMOS process. 相似文献
998.
In many applications, wireless ad-hoc networks are formed by devices belonging to independent users. Therefore, a challenging
problem is how to provide incentives to stimulate cooperation. In this paper, we study ad-hoc games—the routing and packet forwarding games in wireless ad-hoc networks. Unlike previous work which focuses either on routing
or on forwarding, this paper investigates both routing and forwarding. We first uncover an impossibility result—there does
not exist a protocol such that following the protocol to always forward others' traffic is a dominant action. Then we define a novel solution concept called cooperation-optimal protocols. We present Corsac, a cooperation-optimal protocol which consists of a routing protocol and a forwarding protocol. The routing
protocol of Corsac integrates VCG with a novel cryptographic technique to address the challenge in wireless ad-hoc networks
that a link’s cost (i.e., its type) is determined by two nodes together. Corsac also applies efficient cryptographic techniques to design a forwarding protocol
to enforce the routing decision, such that fulfilling the routing decision is the optimal action of each node in the sense that it brings the maximum utility to the node. We evaluate our protocols using simulations.
Our evaluations demonstrate that our protocols provide incentives for nodes to forward packets. Additionally, we discuss the
challenging issues in designing incentive-compatible protocols in ad hoc networks.
Part of this paper appeared in a conference version [49]. Sheng Zhong was supported in part by NSF grants ANI-0207399 and
CNS-0524030. Yang Richard Yang was supported in part by NSF grants ANI-0207399, ANI-0238038, and CNS-0435201. This work was
partly done while Sheng Zhong was at Yale University; Yanbin Liu was at University of Texas at Austin.
Sheng Zhong is an assistant professor in the State University of New York at Buffalo. He received his PhD (2004) from Yale University
and his ME (1999), BS (1996) from Nanjing University, China, all in computer science. His research interests include economic
incentives and privacy protection, particularly incentive and privacy problems in mobile computing and data mining.
Li Erran Li received his B.E. in Automatic Control from Beijing Polytechnic University in 1993, his M.E. in Pattern Recognition from
the Institute of Automation, Chinese Academy of Sciences, in 1996, and his Ph.D. in Computer Science from Cornell University
in 2001 where Joseph Y. Halpern was his advisor. He is presently a member of the Networking Research Center in Bell Labs.
His research interests are in networking with a focus on wireless networking and mobile computing. He has served as a program
committee member for several conferences including ACM MobiCom, ACM MobiHoc, IEEE INFOCOM and IEEE ICNP. He is a guest editor
for JSAC special issue on Non-Cooperative Behavior in Networking. He has published over 30 papers.
Yanbin Liu received her B.E. degree in Computer Science and Technology from Tsinghua University (1993), Beijing, China, in 1993, and
her M.S. degree in Computer Science from the University of Texas at Austin (1998), where is a Ph.D. candidate. Since 2006,
he has been with IBM TJ Watson Research Center, Hawthorne, NY. Her research interests are in real-time systems, grid computing,
mobile computing, and computer networks.
Yang Richard Yang received his B.E. degree in Computer Science and Technology from Tsinghua University, Beijing, China, in 1993, and his M.S.
and Ph.D. degrees in Computer Science from the University of Texas at Austin in 1998 and 2001, respectively. Since 2001, he
has been with the Department of Computer Science, Yale University, New Haven, CT, where currently he is an Associate Professor.
His current research interests are in computer networks, mobile computing, and sensor networks. He leads the Laboratory of
Networked Systems (LANS) at Yale University. 相似文献
999.
Jean-François Saheb Jean-François Richard Mohamad Sawan Remi Meingan Yvon Savaria 《Analog Integrated Circuits and Signal Processing》2007,53(1):27-34
A system integration for High Voltage (HV) electrostatic MicroElectroMechanical Systems (MEMS) actuators is introduced on
a micro-Printed Circuit Board. The system includes a programmable microcontroller, a programmable DC/DC converter, a multi
output HV interface and electrostatic MEMS actuators. The system produces high output voltages (10–300 V) and can control
a large variety of MEMS capacitive loads (1 to 50 pF) by combining diverse semiconductor technologies. This system proves
that technologies, such as low voltage CMOS of different processes, high voltage DMOS and MEMS, can interact, communicate
and even be integrated as a System In Package (SIP), providing significant size and cost reductions. The system was programmed
to control electrostatic MEMS actuator. The DC/DC converter was made from components of different technologies and two addressable
high voltage CMOS interfaces were fabricated with DALSA's 0.8 μm High Voltage process. A prototype of the global system has
been built and tested. 相似文献
1000.
目前正在进行一场竞赛,以期找出下一个网站新秀,能够利用这种铺天盖地的所谓用户自创内容吸引庞大的受众群体;同时,人们也在竞相甄别下一个大趋势,这个趋势将会决定无数网民未来使用网络媒介的方式.5年前,谁会想到博客和社交网络会成为主流? 相似文献