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91.
Dietary fats contribute to the flavor of foods by multiple mechanisms. A role for their taste has only recently gained credence. Current evidence indicates non‐esterified fatty acids (NEFA) are the effective stimuli for the taste component. CD36 and GPR120 are putative receptors, but may not fully account for the totality of the range of sensations elicited by fatty acids. The sensory quality of long‐chain NEFA is not adequately characterized by commonly accepted taste primary qualities and has been termed oleogustus. There is marked individual variability in sensitivity to the taste of NEFA prompting hypotheses of genetic and environmental determinants. Though an association with BMI has been proposed, the preponderance of evidence is not supportive. The importance of oleogustus has not been fully established, but likely contributes to flavor, which influences food choice as well as lipid metabolism and chronic disease risk. A better understanding of oleogustus may provide insights useful for product formulation.  相似文献   
92.
介绍了三种芳香二胺制备双马来酰亚胺树脂的方法及其固化物和芳香二胺改性固化物的力学性能及热性能,从中选出力学性能较好的双马来酰亚胺固化体系胶粘剂。  相似文献   
93.
采用热重分析测试方法对新型马来酰亚胺树脂的耐热性进行了研究,结果表明,用双马来酰亚胺对其改性可取得良好耐热稳定性效果,同时还用红外光谱对树脂改性前后进行了分析并探讨了影响马来酰亚胺树脂耐热稳定性的因素。  相似文献   
94.
直接脑控机器人接口技术   总被引:9,自引:5,他引:4  
直接脑控机器人接口(Brain-controlled robot interface, BCRI)是一种新型的人-机器人接口技术, 是脑-机器接口/脑-计算机接口(Brain-machine interface, BMI/Brain-computer interface, BCI)在机器人控制领域的重要应用和研究方向. 研究者相继在Nature、Science和其他重要国际期刊上报道了相关的实验研究和开发, 目前已成为国际前沿研究热点. 本文主要围绕BCRI中的控制策略、BMI/BCI模块与机器人多层控制模块的适应和融合、BCRI中的脑信号自适应分类算法以及人、BMI/BCI模块和机器人控制系统的三边自适应展开论述, 分析了目前的研究情况、存在的局限和面临的若干重要问题, 指出进一步的研究思路和方向.  相似文献   
95.
Despite the prevalence of pre-obesity and obesity, the physical capabilities of pre-obese/obese individuals are not well documented. As an effort to address this, this study investigated the pre-obesity and obesity impacts on joint range of motion (RoM) for twenty-two body joint motions. A publicly available passive RoM dataset was analysed. Three BMI groups (normal-weight, pre-obese, and obese [Class I]) were statistically compared in joint RoM. The pre-obese and obese groups were found to have significantly smaller RoM means than the normal-weight for elbow flexion and supination, hip extension and flexion, knee flexion and ankle plantar flexion. The pre-obese and obese groups exhibited no significant inter-group mean RoM differences except for knee flexion; for knee flexion, the obese group had significantly smaller RoM means than the pre-obese. The findings would be useful for designing work tasks and products/systems for high BMI individuals and developing digital human models representing differently sized individuals.

Practitioner summary: This study investigated the pre-obesity and obesity impacts on joint range of motion (RoM) by comparing three participant groups: normal-weight; pre-obese and obese. The pre-obese and obese groups had significantly smaller RoM means than the normal-weight for elbow flexion and supination; hip extension and flexion; knee flexion and ankle plantar flexion.

Abbreviations: ANCOVA: Analysis of Covariance; BMI: Body Mass Index; CI: Confidence Interval; RoM: Range of Motion; SPSS: Statistical Package for the Social Sciences  相似文献   

96.
Following a polynomial approach to control design, the simultaneous stabilization by a controller of given fixed order of a family of SISO linear systems is interpreted as an NP-hard BMI feasibility problem. Upon formulating this BMI problem as an LMI problem with an additional non-convex rank constraint, two simultaneous stabilization methods are then proposed. The first method is a heuristic algorithm performing rank minimization by potential reduction. The second method hinges upon necessary conditions and sufficient conditions for simultaneous stabilization derived from geometric properties of the intersection of a set of ellipsoids. Both methods are then illustrated by numerical examples.  相似文献   
97.
There is very little (or no) information about the riding discomfort of motorcyclists in Malaysia. Therefore, this study was done with the intention of highlighting the relationship of the discomfort on the motorcyclist's body parts during the riding process concerning factors such as body mass index (BMI), riding experience, riding hours, and preferred riding posture. This study (questionnaire survey) was done by using 957 respondents (481 males and 476 females) with an age range from 18 years to 24 years, which was collected from a previous study. The results indicate that the majority of motorcyclists who participated in this study are in the normal BMI category. However, the majority of these motorcyclists suffer discomfort in their body parts during the riding process. It is noticeable that the majority of female motorcyclists started with higher discomfort symptoms concerning the corresponding factors (BMI, riding hours, and riding experience) compared with male motorcyclists. Most male discomfort symptoms were focused on the buttock and upper body parts, whereas the female motorcyclists experienced discomfort in all of their body parts (lower, buttocks, and upper body parts). Furthermore, the results also highlight that the motorcyclists' discomfort was correlated with riding posture. Therefore, this study clearly identified that motorcyclists experience discomfort in their body parts during the riding process. The findings also highlight that the current interaction of humans (motorcyclists) and machine (motorcycle) is not an ideal ergonomic philosophy. However, further detailed study (laboratory and field study) needs to be done to uncover fully the parameters or factors that constrain the ergonomic comfortability in the motorcycle riding process. © 2011 Wiley Periodicals, Inc.  相似文献   
98.
Considerable evidence links depression with the development and worsening of diabetes, but the factors contributing to this link have not been established. The authors examined the role of adherence, body mass index (BMI), and self-efficacy. Adult patients with Type 2 diabetes (N = 56) completed self-report measures of diet and exercise adherence, diet and exercise self-efficacy, and depression. BMI was obtained from medical records. Path and mediation analyses indicated that both adherence and BMI independently contributed to self-efficacy. Self-efficacy mediated both the association between adherence and depression and the association between BMI and depression. These findings are consistent with the proposal that lower self-efficacy in reaction to adherence failure and higher BMI contributes to depression in adults with diabetes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
Objective: Previous research indicates that body mass index (BMI) and sex are important factors in understanding physical activity (PA) levels. The present study examined the influence of BMI on psychosocial variables (self-efficacy, social support) and PA in underserved (ethnic minority, low income) boys in comparison with girls. Methods: Participants (N = 669; 56% girls; 74% African American) were recruited from the “Active by Choice Today” trial. Main Outcome Measures:BMI ? score was calculated from objectively collected height and weight data, and PA was assessed with 7-day accelerometry estimates. Self-report questionnaires were used to measure self-efficacy and social support (family, peers) for PA. Results: A 3-way interaction between BMI z score, sex, and family support on PA was shown such that family support was positively associated with PA in normal-weight but not overweight or obese boys, and was not associated with PA in girls. Self-efficacy had the largest effect size related to PA in comparison with the other psychosocial variables studied. Conclusions: Self-efficacy was found to be an important variable related to PA in underserved youth. Future studies should evaluate possible barriers to PA in girls, and overweight youth, to provide more effective family support strategies for underserved adolescents' PA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
This study undertakes to explore the co-varying structure in anthropometric variables that might be affected by the recent surge of overweight and obesity. The increase of overweight and obesity makes the distribution of body dimensions asymmetric by the long tail in distribution (skewness, kurtosis). Principal component analysis (PCA) has been well applied to understand the co-varying body dimensions. However, because PCA decomposes covariance/correlation matrix, the effects of overweight and obesity may not be well captured. Independent component analysis (ICA) is a variant of PCA with the additional assumptions of components being non-Gaussian and independent, in which kurtosis is decomposed. PCA and ICA are applied on the anthropometric data from the North American portion of the Civilian American and European Surface Anthropometry Resource (CAESAR) project. ICA yields more interpretable results by visual inspection than corresponding PCA results. The first independent component (IC 1) is associated with hip/thigh circumferences and chest/waist circumferences and has the largest correlation coefficients with body mass index (BMI). Only the second IC shows the overall size factor that reveals gender difference while principal components 1, 2 and 3 show gender difference. The ICs 3 (torso length) and 4 (arm and leg lengths) are associated with individual differences in body dimensions. The ranges of 38 body dimensions are identified in order to satisfactorily meet the anthropometric variations for both males and females. The ICA gives promise of becoming a valuable tool in the field of ergonomics.  相似文献   
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