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101.
102.
《Measurement》2014
Cochlear implant (CI) provides good auditory performances in quiet, but recognition in noisy environments is still a challenge for CI users. Bilateral hearing can improve speech perception; it has been shown with normal hearing aids, but how source localization is affected is still an open question.In this study source localization is studied in the case of a binaural cochlear implant coding. Signal was received on the two ears and then processed using the classical noise reduction algorithm, suggested by Doerbecker and based on the spectral properties of the signal. Two correction strategies, Ephreim & Malah and Scalart, have been inserted in the processing chain.Tests were conducted, “in simulation” with 20 normal hearing listeners who received a cochlear implant coded signal. An analytic interpretation of the results offers a frame to quantify the different contributions.Results show that the Doerbecker’s algorithm affects the source localization. This effect was lowered when a percentage of the input signal was re-injected into the system. Both correction strategies were equivalent. 相似文献
103.
LEED CI为美国绿色建筑委员会针对商业建筑内部装修的LEED认证评价体系。本文简要介绍了SKF上海世博园办公室改造项目的节能环保相关设计,以供读者参考和借鉴。 相似文献
104.
对传统的演绎的确需要很高的审慎度,判断的标准在于对传统元素的“变形”能力的研究。本文以具体设计项目为载体,讨论了设计团队如何从功能、形式与材料剖析传统建筑元素,以现代科技为根基体现传统国药形象。 相似文献
105.
Visibility, air quality and daily mortality in Shanghai, China 总被引:8,自引:0,他引:8
Wei Huang Haidong Kan Ni Zhao Guixiang Song Lili Jiang Renjie Chen 《The Science of the total environment》2009,407(10):3295-3300
This study was designed to assess the association between visibility and air quality, and to determine whether the variations in daily mortality were associated with fluctuations in visibility levels in Shanghai, China. Mortality data were extracted from the death certificates, provided by Shanghai Municipal Center of Disease Control and Prevention, and visibility data were obtained from Shanghai Municipal Bureau of Meteorology. Air quality data (PM10, PM2.5, PM10-2.5, SO2, NO2 and O3) were obtained from Shanghai Environmental Monitoring Center. Generalized additive model (GAM) with penalized splines was used to analyze the mortality, visibility, air pollution, and covariate data. Among various pollutants, PM2.5 showed strongest correlation with visibility. Visibility, together with humidity, was found appropriate in predicting PM2.5 (R-squared: 0.64) and PM10 (R-squared: 0.62). Decreased visibility was significantly associated with elevated death rates from all causes and from cardiovascular disease in Shanghai; one inter-quartile range (8 km) decrease in visibility corresponded to 2.17% (95%CI: 0.46%, 3.85%), 3.36% (95%CI: 0.96%, 5.70%), and 3.02% (95%CI: − 1.32%, 7.17%) increase of total, cardiovascular and respiratory mortality, respectively. The effect estimates using predicted PM2.5 and PM10 concentrations were similar to those assessed using actual concentrations. This is the first study in Mainland China assessing the association between visibility and adverse health outcomes. Our findings suggest the possibility of using visibility as a surrogate of air quality in health research in developing countries where air pollution data might be scarce and not routinely monitored. 相似文献
106.
Roberto de Marco Alessandro Marcon Lucia Cazzoletti Caterina Silocchi 《The Science of the total environment》2010,408(3):511-517
Emissions related to wood production processes are a recognized health hazard for professionally exposed subjects. The health effects of living close to wood industries are not known, particularly in the pediatric population. We aimed at investigating if living close to chipboard industries is a health hazard for the children in the Viadana district (Northern Italy).In December 2006, all the children (3-14 years) living in the Viadana district, where two big chipboard industries are located, were surveyed through a parental questionnaire (n = 3854). The children were geocoded, and the distance of their houses/schools from the closest wood plant was computed.Independently of sex, age, nationality, residential area, traffic, parents' education, passive/parental smoking, questionnaire compiler and his/her environmental concern, the children living at < 2 km from chipboard industries had a greater prevalence of respiratory (OR = 1.33, 95%CI: 1.11, 1.60), cough/phlegm (OR = 1.43, 95%CI: 1.08, 1.88), nose/throat/mouth (OR = 1.47, 95%CI: 1.23, 1.75), eye (OR = 1.24, 95%CI: 1.04, 1.48) symptoms, school-days lost (OR = 1.24, 95%CI: 1.04, 1.48), and emergency (OR = 2.14, 95%CI: 1.47, 3.11) and hospital (OR = 2.21, 95%CI: 1.17, 4.18) admissions. There was an inverse dose-response relationship between the adverse health outcomes considered and the distance from the plants. The attributable fractions for the children living close to the chipboard industries were substantial, ranging from 13% (eye symptoms) to 27% (cough/phlegm).The present findings suggest that emissions from chipboard industries might have a serious impact on children's health status and should therefore be reduced and closely monitored. 相似文献
107.
Uwe Schlink Alexander Thiem Tibor Kohajda Matthias Richter Kathrin Strebel 《The Science of the total environment》2010,408(18):3840-3851
There are many factors determining the concentration of volatile organic compounds (VOCs) in indoor air. On the basis of 601 population-based measurements we develop an explicit exposure model that includes factors, such as renovation, furniture, flat size, smoking, and education level of the occupants.As a novel method for the evaluation of concentrations of indoor air pollutants we use quantile regression, which has the advantages of robustness against non-Gaussian distributions (and outliers) and can adjust for unbalanced frequencies of observations. The applied bi- and multivariate quantile regressions provide (1) the VOC burden that is representative for the population of Leipzig, Germany, and (2) an inter-comparison of the effects of the studied factors and their levels.As a result, we find strong evidence for factors of general impact on most VOC components, such as the season, flooring, the type of the room, and the size of the apartment. Other impact factors are very specific to the VOC components. For example, wooden flooring (parquet) and new furniture increase the concentration of terpenes as well as the modifying factors high education and sampling in the child's room. Smokers ventilate their flats in an extent that in general reduces the VOC concentrations, except for benzene (contained in tobacco smoke), which is still higher in smoking than in non-smoking flats. Very often dampness is associated with an increased VOC burden in indoor air.An investigation of mixtures emphasises a high burden of co-occurring terpenes in very small and very large apartments. 相似文献
108.
为了系统化地理解和发展集体智慧理论,并进一步探索如何利用集体智慧理论解决制造领域特别是社群化制造领域中的工程问题,在统计2000年至今的中英文集体智慧相关研究文献基础上,进行了相关概念辨析,并根据集体智慧系统中个体属性差异将其分为人类系统、社会性动植物系统以及人工智能体系统集体智慧三类,然后按"实现框架—关键技术—工程应用"的主线对三类集体智慧的理论研究进展及其在制造领域的应用研究现状进行了综述。研究结果表明,集体智慧理论在社群化制造各环节均有广泛应用前景。据此提出了集体智慧概念集成框架,并探讨了其在社群化制造领域的初步应用方案和需要解决的问题。 相似文献
109.
以化合物Zn(NH4)3Cl5为气相输运剂,ZnSe多晶为原料,用化学气相输运技术(CVT)在封闭石英管中生长出直径9 m m、长度25 mm的Zn1+0 031Se单晶晶体生长区的温度为898~915℃,温度梯度为1.5℃@cm-1,生长周期为21 d.晶体生长端由{111}和{100}单形包围.用RO-XRD技术研究了晶体的结晶质量,ZnSe(111)的RO-XRD谱的FWHM为24 s.光致发光特性研究表明,Zn1+0.031Se单晶体的PL谱由Fx(439 nm)和BBT(418 nm)等发光峰组成,晶体的短波吸收限位于465 nm处,腐蚀点密度为(5~7)×104cm-2.化合物Zn(NH4)3Cl5具有较高的热稳定性,是一种适合气相生长ZnSe单晶的新型输运剂. 相似文献
110.