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161.
Odors seem to be perceived differently when presented ortho- or retronasally. In this study, stimuli of controlled concentration and duration were applied in either the anterior nasal cavity or epipharynx by means of air-dilution olfactometry. Stimulus concentration was monitored in the olfactory cleft. In Experiment 1, odor thresholds to a food (chocolate) and a nonfood (lavender) odor were lower for orthonasal, compared with retronasal, stimulation. In Experiment 2, intensity ratings to suprathreshold odor concentrations were significantly higher for orthonasal than for retronasal stimulation with hydro- hydrogen sulfide, but not phenyl ethyl alcohol. Accordingly, amplitudes and latencies of olfactory event-related gen potentials to retronasal stimuli were found to be smaller and prolonged, respectively. This indicates differential processing of olfactory stimuli presented through the retronasal or orthonasal routes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
162.
Thomas Deiß 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(4):347-352
When deploying TTCN-3 at Nokia, we converted two TTCN-2 test systems to TTCN-3. We explain to which extend we have been able
to do the conversion automatically. The conversion tool used provided a syntactically and semantically correct conversion
of the TTCN-2 code. We define some improvements made on the tool to increase readability and maintainability of the resulting
code. We cover aspects of converting also the non-TTCN-2 parts and describe the experiences we made as a set of lessons learnt. 相似文献
163.
In this paper, we present the findings from an extensive study of the use of virtual reality (VR) models in large construction projects. The study includes two parts: The first part presents a quantitative questionnaire designed to investigate how VR models are experienced and assessed by the workforce at a building site. The second part includes a qualitative field survey of how VR models can be applied and accepted by professionals in the design and planning process of a large pelletizing plant. Through mainly studying persons who had little or no experience with advanced information technology (IT), we hoped to reveal the attitudes of the average person working at a construction site rather than of an IT expert. In summary, the study shows that the VR models in both projects have been very useful and well accepted by the users. Today’s information flow is, from a general point of view, considered to be insufficient and the hypothesis is that using VR models in the construction process have the potential to minimize waste of resources and improve the final result. 相似文献
164.
通过理论分析和实验研究液晶分子附着能和液晶盒间隙对响应时间(τ0)的影响。用液晶盒有效间隙法和表面动力学方程法两种方法推出分析公式,由这两种方法推出的结果是一致的。实验数据与简化方程τ0-dx基本拟合(其中d是液晶盒的间隙,x是指数)。在两种极端的(极大或极小)附着能极限下,指数x分别接近2和1。这个结论有助于优化液晶显示器件的应用。 相似文献
165.
Peichun Li Amar Zerroukhi Jianding Chen Yvan Chalamet Thomas Jeanmaire Zhean Xia 《应用聚合物科学杂志》2008,110(6):3990-3998
Chemical shrinkage was used for the in situ measurement of the progressing chemical stabilization reactions and the influence of ozone during the stabilization of polyacrylonitrile. A method for evaluating the activation energy through the sensitivity temperature is presented. The calculated results show that the activation energies were 161.57 kJ/mol in air and 181.23 kJ/mol in ozone-enriched air. Therefore, the chemical reactions were postponed during stabilization in ozone-enriched air. Ozone seemed to act in three ways: first, ozone promoted the formation of the serious skin–core structure. Second, ozone accelerated the chemical reactions and shortened the stabilization time at lower heating rates. Third, ozone postponed the chemical reactions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
166.
A non-invasive headspace analysis method to measure rate and amount of oxygen uptake in oxygen-scavenging polymers is presented. Oxygen uptake data for metal-catalyzed poly(1,4-butadiene) at 30 °C are provided to illustrate the method. These data were obtained by measuring oxygen headspace concentration above the scavenging polymer with an OxySense® 200T non-invasive oxygen sensor, and, for comparison, oxygen uptake was measured with an analytical balance. Excellent agreement was observed between these two independent experiments. 相似文献
167.
Do experiences make people happier than material possessions? In two surveys, respondents from various demographic groups indicated that experiential purchases-those made with the primary intention of acquiring a life experience--made them happier than material purchases. In a follow-up laboratory experiment, participants experienced more positive feelings after pondering an experiential purchase than after pondering a material purchase. In another experiment, participants were more likely to anticipate that experiences would make them happier than material possessions after adopting a temporally distant, versus a temporally proximate, perspective. The discussion focuses on evidence that experiences make people happier because they are more open to positive reinterpretations, are a more meaningful part of one's identity, and contribute more to successful social relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
168.
The article discusses trade-offs involved in current-generation autonomy systems for deep-space applications and describes emerging research that will let future spacecraft operate unattended for significant periods of time, synthesizing control decisions in response to both planned and unplanned events. 相似文献
169.
Femoral artery pseudoaneurysms (PSA or false aneurysm) develop in about 1% of patients undergoing procedures that require femoral artery cannulation. PSA prolong hospitalization, consuming health-care resources, and result in significant morbidity. We designed a study to review the prevalence, risk factors, and treatment of PSA. We performed a retrospective, case-controlled study of patients diagnosed with PSA at a large, urban, tertiary-care teaching hospital. We reviewed 48 patients with PSA for our study. The estimated prevalence of PSA was 0.28%, with identical rates found for procedures done in the interventional radiology department and in the cardiac catheterization suite. Logistic regression identified three independent risk factors for developing PSA: being female (odds ratio 2.62), having an intervention performed (odds ratio 3.22), and not having a closure device used (odds ratio 10.2). Patients with PSA had longer hospital length of stay than that of patients without PSA. We found no statistically significant difference in failure or complication rates for the four treatment options and that spontaneous resolution of PSA does not correlate with its size. Thrombin injection and observation are effective, low-complication treatment options. 相似文献
170.
A.N. Al-Omari G.P. Carey S. Hallstein J.P. Watson G. Dang K.L. Lear 《Photonics Technology Letters, IEEE》2006,18(11):1225-1227
Increasing copper plated heatsink radii from 0 to 4 /spl mu/m greater than the mesa in vertical-cavity surface-emitting lasers (VCSELs) reduced the measured thermal resistance for a range of device sizes to values 50% lower than previously reported over a range of device sizes. For a 9-/spl mu/m diameter oxide aperture, the larger heatsink increases output power and bandwidth by 131% and 40%, respectively. The lasers exhibit a 3-dB modulation frequency bandwidth up to 9.8 GHz at 10.5 kA/cm/sup 2/. The functional dependence of thermal resistance on oxide aperture diameter indicates the importance of lateral heat flow to mesa sidewalls. 相似文献