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排序方式: 共有835条查询结果,搜索用时 15 毫秒
1.
Huseyin Avci Esra Akkulak Hazal Gergeroglu Hamed Ghorbanpoor Onur Uysal Ayla Eker Sariboyaci Bahar Demir Merve Nur Soykan Suat Pat Reza Mohammadigharehbagh Ceren Özel Ahmet Cabuk Fatma Doğan Güzel 《应用聚合物科学杂志》2020,137(26):49184
Among the thermoplastic elastomers that play important roles in the polymer industry due to their superior properties, styrene-based species and polyurethane block copolymers are of great interest. Poly(styrene-ethylene-butadiene-styrene) (SEBS) as a triblock copolymer seems to have the potential to meet many demands in different applications due to various industrial requirements where durability, biocompatibility, breaking elongation, and interfacial adhesion are important. In this study, the SEBS triblock copolymer was functionalized with natural (Satureja hortensis, SH) and synthetic (nanopowder, TiO2) agents to obtain composite nanofibers by electrospinning and electrospraying methods for use in biomedical and water filtration applications. The results were compared with thermoplastic polyurethane (TPU) composite nanofibers, which are commonly used in these fields. Here, functionalized SEBS nanofibers exhibited antibacterial effect while at the same time improving cell viability. In addition, because of successful water filtration by using the SEBS composite nanofibers, the material may have a good potential to be used comparably to TPU for the application. 相似文献
2.
在重点说明影响传输光纤设计的主要问题的同时,简要介绍了各种升级方式所面临的主要技术挑战,并详细说明这些挑战对传输光纤提出的技术要求。 相似文献
3.
Emery Robert E.; Matthews Sheila G.; Kitzmann Katherine M. 《Canadian Metallurgical Quarterly》1994,62(1):124
A 1-yr follow-up study was conducted on families randomly assigned to settle custody disputes either in mediation or through adversary procedures. Consistent with Time 1 reports, at Time 2 fathers who mediated were substantially more satisfied than were fathers who litigated. Fathers who mediated also complied more with child support orders. Contrary to prediction, the greater satisfaction and compliance of fathers did not lead to increased satisfaction among mothers who mediated. In contrast to Time 1, at follow-up mothers who mediated were significantly less satisfied than were mothers who litigated, but selective attrition may account for these differences. The psychological adjustment of mothers and fathers was not significantly different between settlement groups at Time 2, but mothers in both groups reported less satisfaction with dispute settlement and less dysphoria at Time 2 than they had reported at Time 1. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
The space heating energy needed during the winter heating season in Seattle Washington, USA, was monitored over a 15-year period, 1987–2002. Two single family residence houses were constructed to building code standards in force at the time of construction and two to standards calling for envelopes with improved thermal resistance. Space conditioning energy needs are strongly affected by occupant behavior, but generally simulations ignore the behavior of the occupants in estimating the energy needed for heating and cooling. The data suggest that estimates of energy savings can be based upon envelope thermal resistance for moderate occupant behavior. For such behavior, the space heating is well characterized by the daily average difference between house average space temperature and outside air temperature. Characterizing in terms of indoor temperature, outdoor air temperature, wind speed, and insolation gives a slightly better representation but requires more information than is usually available. However, vigorous conservation tactics, which produce a thermal response that is highly transient, can lead to substantially different energy needs. No correlation could be established from the measured space heating when aggressive conservation made use of thermostat setback at every opportunity. 相似文献
5.
D McGonagle W Gibbon P O''Connor M Green C Pease P Emery 《Canadian Metallurgical Quarterly》1998,41(4):694-700
Although studies generally support a positive association between alcohol consumption and lung-cancer risk, the relationship between specific alcoholic beverages and lung-cancer risk has been inconsistent. We examined recent and past alcoholic beverage intake among 261 incident cases and 615 population controls enrolled in a lung-cancer case-control study of African Americans and Caucasians in Los Angeles County between 1991 and 1994. An in-person interview elicited information about past alcohol intake from ages 30 to 40 y, smoking, other lung-cancer risk factors, as well as recent intake of alcohol, and recent dietary intake. An association was observed between recent hard-liquor consumption and lung-cancer risk. The odds ratio (OR) for 1 or more drinks (1.5 oz or 0.051 mL) per day of hard liquor compared with infrequent liquor drinking (0-3 drinks per month), adjusted for smoking, the matching factors, saturated fat and other alcoholic beverages was 1.87 [95% confidence interval (CI) = 1.02-3.42]. No appreciable association was observed for total alcohol, whereas small inverse associations were observed for beer and wine, although confidence intervals were wide. An elevated lung-cancer risk was also observed for past liquor consumption (between ages 30 and 40 y). The adjusted OR for 1 or more drinks per day of liquor compared with infrequent drinkers was 1.83 (95% CI = 1. 06-3.15). Confounding of the association between alcohol and lung cancer by smoking was apparent. Although we devoted considerable efforts to adjusting for smoking in our analyses, residual confounding is still possible because smoking and alcohol are closely associated. In addition, case-control studies including this study should be viewed with caution because of possible selection bias. An increased risk of lung cancer might occur with moderate drinking of hard liquor but confirmation is required in larger studies. 相似文献
6.
Thomas Emery 《Journal of population ageing》2012,5(1):7-22
The anticipated, dramatic shift in the demographics of European societies over the next half a century begs many questions about the state of relations between generations. Papers and speculations portraying a world in which the elderly rule through parliamentary majorities, preventing reductions in pensions and ??enslaving?? the working population are surprisingly common. Existing literature on these hypotheses focus on the policy preference differences between the young and the old with evidence mixed as to the accuracy of these predictions. This paper aims to build on this debate by looking at the effects that the dependency ratio has on intergenerational relations. By using a multilevel methodology and data from the 2008 European Social Survey, the effect of demographic structure can be observed on the individual level. Yet whilst evidence is found of decreasing legitimacy of welfare for the elderly, this paper argues that this does not point to increasing intergenerational conflict in Europe. 相似文献
7.
Isabelle Guyon Vassilis Athitsos Pat Jangyodsuk Hugo Jair Escalante 《Machine Vision and Applications》2014,25(8):1929-1951
This paper describes the data used in the ChaLearn gesture challenges that took place in 2011/2012, whose results were discussed at the CVPR 2012 and ICPR 2012 conferences. The task can be described as: user-dependent, small vocabulary, fixed camera, one-shot-learning. The data include 54,000 hand and arm gestures recorded with an RGB-D \(\hbox {Kinect}^\mathrm{TM}\) camera. The data are organized into batches of 100 gestures pertaining to a small gesture vocabulary of 8–12 gestures, recorded by the same user. Short continuous sequences of 1–5 randomly selected gestures are recorded. We provide man-made annotations (temporal segmentation into individual gestures, alignment of RGB and depth images, and body part location) and a library of function to preprocess and automatically annotate data. We also provide a subset of batches in which the user’s horizontal position is randomly shifted or scaled. We report on the results of the challenge and distribute sample code to facilitate developing new solutions. The data, datacollection software and the gesture vocabularies are downloadable from http://gesture.chalearn.org. We set up a forum for researchers working on these data http://groups.google.com/group/gesturechallenge. 相似文献
8.
This article summarizes the results of Executive Perspectives on Top Risks for 2015, a study conducted by North Carolina State University’s ERM Initiative and Protiviti. For more information, visit www.protiviti.com/TopRisks. 相似文献
9.
This article presents a series of user studies to develop a new eye-gaze tracking–based pointing system. We developed a new target prediction model that works for different input modalities and combined the eye-gaze tracking–based pointing with a joystick controller that can reduce pointing and selection times. The system finds important applications in cockpit of combat aircraft and for computer novice users. User studies confirmed that users can perform significantly faster using this new eye-gaze tracking–based system for both military and everyday computing tasks compared to existing input devices. As part of the study it was also found that the amplitude of maximum power component obtained through Fourier Transform of pupil signal significantly correlates with selection times and perceived cognitive load of users in terms of Task Load Index scores. 相似文献
10.
The modeling of uncertainty in continuous and categorical regionalized variables is a common issue in the geosciences. We present a hybrid continuous/categorical model, in which the continuous variable is represented by the transform of a Gaussian random field, while the categorical variable is obtained by truncating one or more Gaussian random fields. The dependencies between the continuous and categorical variables are reproduced by assuming that all the Gaussian random fields are spatially cross-correlated. Algorithms and computer programs are proposed to infer the model parameters and to co-simulate the variables, and illustrated through a case study on a mining data set. 相似文献