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11.
This paper reports on a design experience for undergraduates in computer engineering, industrial design, and marketing that focuses on pervasive computing devices. Across a broad range of targeted application areas and user groups, many of the student designs have been wearable computers. Consequently, our course will be of interest to the wearable computing community, particularly in terms of our aim of bridging the gap between design and engineering. For the two most recent offerings of the course, we have utilized external observers and surveyed the students in order to validate the impact of aspects of our process and changes to it. This paper is based upon 5 years of experience and 2 years of analysis of our course, and it presents an overview of our process with both qualitative and quantitative results from these two most recent offerings.  相似文献   
12.
This paper is concerned with the derivation of infinite schedules for timed automata that are in some sense optimal. To cover a wide class of optimality criteria we start out by introducing an extension of the (priced) timed automata model that includes both costs and rewards as separate modelling features. A precise definition is then given of what constitutes optimal infinite behaviours for this class of models. We subsequently show that the derivation of optimal non-terminating schedules for such double-priced timed automata is computable. This is done by a reduction of the problem to the determination of optimal mean-cycles in finite graphs with weighted edges. This reduction is obtained by introducing the so-called corner-point abstraction, a powerful abstraction technique of which we show that it preserves optimal schedules. This work has been mostly done while visiting CISS at Aalborg University in Denmark and has been supported by CISS and by ACI Cortos, a program of the French Ministry of Research.  相似文献   
13.
这是一位四海为家的瑞典籍天才运动图形插画家,她将会为你展示自己对肌理的热衷以及为什么你无需害怕黑暗的一面……  相似文献   
14.
It is shown that several recursive least squares (RLS) type equalization algorithms such as, e.g., decisiondirected schemes and orthogonalized constant modulus algorithms, possess a common algorithmic structure and are therefore rather straightforwardly implemented on an triangular array (filter structure) for RLS estimation with inverse updating. While the computational complexity for such algorithms isO(N 2), whereN is the problem size, the throughput rate for the array implementation isO(1), i.e., independent of the problem size. Such a throughput rate cannot be achieved with standard (Gentleman-Kung-type) RLS/QR-updating arrays because of feedback loops in the computational schemes.  相似文献   
15.
Information Seeking Can Be Social   总被引:3,自引:0,他引:3  
Chi  Ed H. 《Computer》2009,42(3):42-46
For reasons ranging from obligation to curiosity, users have a strong inclination to seek information from others during the search process. Search systems using statistical analytics over traces left behind by others can help support the search experience.  相似文献   
16.
A number of studies have considered whether background stress affects cardiovascular responses to acute stress tasks. The present study considers the effect of a potent background stressor with a clear onset, namely the terrorist attacks on September 11, 2001. Specifically, the authors investigated differences among 9.5-year-old children tested before (N = 30) and then following (N = 20) the 9/11 attacks. In addition, a majority of these children (N = 37) were retested approximately 1 year later (i.e., before and after 9/11/2002). Children tested directly following 9/11/2001 exhibited significantly greater stroke volume and cardiac output responses to acute stress tasks compared with their responses 1 year later, and this change in reactivity differed significantly from the change in reactivity exhibited by children tested before 9/11/2001 and again 1 year later. These results suggest that a potent background stressor can temporarily heighten some children's cardiovascular responses to subsequent acute stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
Smith  Ed 《ITNOW》2003,45(5):18-19
  相似文献   
18.
The Accreditation Board for Engineering and Technology (ABET) has adopted a revised set of criteria for accrediting engineering programs. Nevertheless, as in the past, civil engineering departments will be required to demonstrate proficiency in specific subject areas which are included in the ABET program criteria. This paper investigates how civil engineering students at Lamar University improved their understanding of various subject areas required by ABET and listed in the Program Criteria for Civil and Similarly Named Engineering Programs and the General Criteria (professional component) by being involved with cooperative, part-time, and summer work experiences. In particular, the findings suggest that both undergraduate and graduate students believe that three areas have been greatly enhanced with engineering work. They include structural engineering, project management/scheduling and estimating, and teamwork. In addition, undergraduates perceive that their understanding of health and safety issues and ethical considerations has also increased. In contrast, graduate students believe that their knowledge of hydraulics, hydrology, and water resources, constructability, and economic factors has been enhanced by civil engineering work experiences.  相似文献   
19.
The use of fluorescent probes that allow visualization of leukocyte-endothelial cell (EC) interactions has greatly informed our understanding of leukocyte recruitment. However, effects of these agents on the biological functions of leukocytes are poorly described, leading to concerns about the interpretation of such data. Here we used two flow-based neutrophil adhesion assays to compare the effects of phase contrast illumination (PCI) with high intensity illumination (HII) used for fluorescent microscopy, in the presence or absence of five commonly used fluorochromes. Isolated neutrophils were either (1) perfused across P-selectin to establish a population of rolling cells, which were subsequently activated with fMLP; or (2) perfused across EC activated with TNF-alpha. In the absence of fluorescent dyes, HII did not affect levels of leukocyte adhesion; however, subsequent neutrophil behavior was dramatically altered when compared with cells under PCI, for example, dramatically reducing their migration velocities. In the presence of fluorescent dyes, the effects of HII were exacerbated, although the precise nature of the biological effects of these probes was agent specific. Thus, for the first time, our experiments describe the effects of fluorescent microscopy on the separate stages of the neutrophil recruitment process and reveal a previously unsuspected effect of HII on neutrophil migration.  相似文献   
20.
A tendency toward abstract and overgeneral processing is a cognitive bias hypothesized to causally contribute to symptoms of depression. This hypothesis predicts that training dysphoric individuals to become more concrete and specific in their thinking would reduce depressive symptoms. To test this prediction, 60 participants with dysphoria were randomly allocated either to (a) concreteness training; (b) bogus concreteness training, matched with concreteness training for treatment rationale, experimenter contact, and treatment duration but without active engagement in concrete thinking; (c) a waiting-list, no training control. Concreteness training resulted in significantly greater decreases in depressive symptoms and significantly greater increases in concrete thinking than the waiting-list and the bogus training control, and significantly greater decreases in rumination than the waiting-list control. These findings suggest that concreteness training has potential as a guided self-help intervention for mild-to-moderate depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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