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1.
Objectives: Examine the effectiveness of an intervention to increase fruits and vegetables (FV) consumption among smokers. Design: Cluster-randomized trial of 20 public housing developments; 10 randomly assigned to an FV intervention and 10 to a smoking cessation intervention. Main outcome measures: Usual (past 7 days) and past 30 days change in daily FV intake at 8 weeks and 6 months postbaseline. Results: Greater increases were seen in the FV group. At Week 8 and Month 6, the FV group had consumed 1.58 (p = .001) and 0.78 (p = .04), respectively, more daily FV servings in the past 7 days than the cessation group. At the same time points, the FV group had consumed 3.61 (p = .01) and 3.93 (p = .01), respectively, more FV servings in the past 30 days than the cessation group. Completing more motivational interviewing sessions (p = .02) and trying more recipes (p = .02) led to significantly greater increases at Month 6 among FV participants. Conclusions: Motivational interviewing counseling and lifestyle modification through trying out healthy recipes may be effective in helping a high-risk population increase their FV intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
This paper presents a nonlinear inverse optimization approach to determine the weights for the joint displacement function in standing reach tasks. This inverse optimization problem can be formulated as a bi-level highly nonlinear optimization problem. The design variables are the weights of a cost function. The cost function is the weighted summation of the differences between two sets of joint angles (predicted posture and the actual standing reach posture). Constraints include the normalized weights within limits and an inner optimization problem to solve for joint angles (predicted standing reach posture). The weight linear equality constraints, obtained through observations, are also implemented in the formulation to test the method. A 52 degree-of-freedom (DOF) human whole body model is used to study the formulation and visualize the prediction. An in-house motion capture system is used to obtain the actual standing reach posture. A total of 12 subjects (three subjects for each percentile in stature of 5th percentile female, 50th percentile female, 50th percentile male and 95th percentile male) are selected to run the experiment for 30 tasks. Among these subjects one is Turkish, two are Chinese, and the rest subjects are Americans. Three sets of weights for the general standing reach tasks are obtained for the three zones by averaging all weights in each zone for all subjects and all tasks. Based on the obtained sets of weights, the predicted standing reach postures found using the direct optimization-based approach have good correlation with the experimental results. Sensitivity of the formulation has also been investigated in this study. The presented formulation can be used to determine the weights of cost function within any multi-objective optimization (MOO) problems such as any types of posture prediction and motion prediction.  相似文献   
3.
This article develops and tests an ethnographic decision model (EDM) of hydrogen fuel cell vehicle (FCV) adoption using interviews with California residents that either actually adopted an FCV or “seriously considered” doing so before deciding against it. We developed an initial model from 25 semi-structured interviews in which respondents self-described their decision-making processes. We iteratively tested and refined the model in a second round of 53 structured interviews. The final model consists of a first stage that assesses FCV adoption feasibility and a second stage that compares FCVs to other vehicle types. The model ultimately correctly predicts 86.8% of cases in the sample. In the first stage, respondents preferred to satisfy their need for a primary refueling station near home but a substantial number were willing to rely on a station near or on the way to work or other destination. Most drivers required a convenient backup station and a means of managing long-distance trips. Vehicle size options eliminated a few respondents. None rejected FCV adoption due to insufficient driving range. In the second stage, nearly all drivers engaged in some kind of cost comparison, though the factors considered varied greatly. Most opted for what they viewed as the less costly option, although a few FCV adopters and non-adopters were willing to pay more for their more preferred option. EDM is a promising qualitative research method for generating insights into how people navigate the decision whether or not to get an alternative-fuel vehicle.  相似文献   
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In 2007, the UK Government announced an ambitious zero-carbon target for all new housing in England. This paper shows how the definition and its associated policies emerged from discourses of environmental policy innovation; how the problem subsequently became framed as one of mainstreaming, consequent upon the apparent success of experimental schemes and defined in more detail through the interaction between pressure group politics and the technical analyses that accompanied the government's consultation exercises. Finally, it shows how regional and local variations in housing and property markets are likely to influence the ease of zero carbon development. The analysis uses concepts drawn from both the science and technology literature and the literature on policy implementation.  相似文献   
6.
Economically and culturally important salmonid species often compete with Atlantic salmon (Salmo salar) released from stocking programs or that escaped during aquaculture production. Such competitive interactions may lower the individual fitness of these species by reducing survival and body growth. Here, we exposed juvenile brown trout (S. trutta), rainbow trout (Oncorhynchus mykiss), Chinook salmon (O. tshawytscha), and coho salmon (O. kisutch) to juvenile Atlantic salmon in artificial streams for 10 months. Survival and fitness-related traits of the four species were not negatively impacted by the presence of Atlantic salmon. The results suggest that brown trout and rainbow trout have better competitive abilities than Atlantic salmon, and that Chinook salmon and coho salmon have limited competitive interactions with Atlantic salmon. Although we discuss certain environmental conditions that can favor Atlantic salmon as a competitor at the juvenile life stage, Atlantic salmon may have little impact on the productivity of these four species.  相似文献   
7.
The understanding of violent criminal behavior is hindered by definitional problems in both the legal and research communities. Different definitions of violent criminal behavior and different classifications of the severity of violence are fundamental problems that need to be resolved in order to develop better conceptual models of the precursors to criminal violence that can inform management and treatment of violent young offenders. This study evaluated 6 classifications of violent juvenile offenses derived from the legal system and published research. The authors compare frequencies from different classifications and examine the influence of classifications on observed associations with expected predictor variables. Differences in frequencies and perceived associations between classifications highlight the need to adopt a consistent method of coding violent offenses for research purposes in order to obtain valid results that are capable of informing policy, the judiciary, and the development of effective interventions. The final classification system offers a method of systematic coding based on the type, frequency, and outcome of the violent behavior that distinguishes between levels of violence severity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
In a 4-wave, 2-year longitudinal design, the authors obtained measures of negative affect (NA) and self-perceived competence from 220 boys and 216 girls who were 7th graders at the beginning of this study. NA was operationalized as the common dimension underlying self-reports of depressive symptoms, anxiety symptoms, and negative emotions. Self-perceived competence consisted of 2 higher order constructs: a well-behaved/good-student factor and an attractive/athletic/popular factor. Structural equation modeling revealed very high stability estimates for all constructs. Nevertheless, self-perceived competence in the attractive/athletic/popular domain predicted changes in NA. Conversely, NA predicted changes in self-perceived competence in the well-behaved/good-student domain. The primacy of NA versus self-cognitions depends, in part, on the type of self-cognitions being examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Cooperative conversation has been shown to foster interpersonal postural coordination. The authors investigated whether such coordination is mediated by the influence of articulation on postural sway. In Experiment 1, talkers produced words in synchrony or in alternation, as the authors varied speaking rate and word similarity. Greater shared postural activity was found for the faster speaking rate. In Experiment 2, the authors demonstrated that shared postural activity also increases when individuals speak the same words or speak words that have similar stress patterns. However, this increase in shared postural activity is present only when participants' data are compared with those of their partner, who was present during the task, but not when compared with the data of a member of a different pair speaking the same word sequences as those of the original partner. The authors' findings suggest that interpersonal postural coordination observed during conversation is mediated by convergent speaking patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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