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81.
Pollution phenomena are complex systems in which different parts are integrated by means of causal and temporal relationships. To understand pollution, children must develop some cognitive abilities related to system thinking and temporal and causal inferential reasoning. These cognitive abilities constrain and guide how children understand pollution processes. Hence, ascertaining whether changes among children’s ideas of pollution are related to system thinking and inferential reasoning abilities could be useful in improving environmental education. Eighty participants between 9 and 16 years old were interviewed to evaluate how children explain different aspects of pollution-related systems. From the explanations found in these interviews, three progressive epistemic structures were reconstructed. The three epistemic structures differ in the type of causal and temporal relationship established by the participants and in the mechanisms that the participants used to relate the pollutant to its effects.  相似文献   
82.
Ethics and Information Technology - Automated vehicles (AVs) are expected to operate on public roads, together with non-automated vehicles and other road users such as pedestrians or bicycles....  相似文献   
83.
The aim of this study was to determine which physiological variables predict excellence in middle- and long-distance runners. Forty middle-distance runners (age 23 ± 4 years, body mass 67.2 ± 5.9 kg, stature 1.80 ± 0.05 m, VO(2max) 65.9 ± 4.5 ml · kg(-1) · min(-1)) and 32 long-distance runners (age 25 ± 4 years, body mass 59.8 ± 5.1 kg, stature 1.73 ± 0.06 m, VO(2max) 71.6 ± 5.0 ml · kg(-1) · min(-1)) competing at international standard performed an incremental running test to exhaustion. Expired gas analysis was performed breath-by-breath and maximum oxygen uptake (VO(2max)) and two ventilatory thresholds (VT(1) and VT(2)) were calculated. Long-distance runners presented a higher VO(2max) than middle-distance runners when expressed relative to body mass (P < 0.001, d = 1.18, 95% CI [0.68, 1.68]). At the intensities corresponding to VT(1) and VT(2), long-distance runners showed higher values for VO(2) expressed relative to body mass or %VO(2max), speed and oxygen cost of running (P < 0.05). When oxygen uptake was adjusted for body mass, differences between groups were consistent. Logistic binary regression analysis showed that VO(2max) (expressed as l · min(-1) and ml · kg(-1) · min(-1)), VO(2VT2) (expressed as ml · kg(-0.94) · min(-1)), and speed at VT(2) (v(VT2)) categorized long-distance runners. In addition, the multivariate model correctly classified 84.7% of the athletes. Thus, VO(2max), VO(2VT2), and v(VT2) discriminate between elite middle-distance and long-distance runners.  相似文献   
84.
This study seeks to discover whether handball goalkeepers employ a general anticipatory strategy when facing long distance throws and the effect of uncertainty on these strategies. Seven goalkeepers and four throwers took part. We used a force platform to analyse the goalkeeper's movements on the basis of reaction forces and two video cameras synchronised at 500 Hz to film the throw using 3D video techniques. The goalkeepers initiated their movement towards the side of the throw 193 ± 67 ms before the release of the ball and when the uncertainty was reduced the time increased to 349 ± 71 ms. The kinematics analysis of their centre of mass indicated that there was an anticipatory strategy of movement with certain modifications when there was greater uncertainty. All the average scores referring to velocity and lateral movement of the goalkeeper's centre of mass are significantly greater than those recorded for the experimental situation with bigger uncertainty. The methodology used has enabled us to tackle the study of anticipation from an analysis of the movement used by goalkeepers to save the ball.  相似文献   
85.
In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.  相似文献   
86.
The renaissance frescoes of the metropolitan cathedral of Valencia, located at the vault of the apse, were restored in 2006. We describe a microclimate monitoring system that was implemented for the preventive conservation of the paintings. It is comprised by a set of temperature and relative humidity sensors positioned at different points of the vault. This system is rather unique because some of these sensors were inserted inside the paintings during the restoration process. A principal components analysis was applied to the data of relative humidity recorded in February 2007. The analysis was repeated in three additional months of 2007. The resulting loading plots highlight the most relevant similarities and dissimilarities among sensors. These plots can be considered as some sort of control maps that could be used to detect abnormal conditions in the future. Actually, moisture problems at certain zones of the frescoes are causing the formation of efflorescence, and the sensors located close to these zones are the ones recording the highest values of relative humidity.  相似文献   
87.
This paper examines re-training transition processes as a basis for understanding adult learning and career change. The paper distinguishes between frame breaking and incremental change, describes learning methods associated with these levels of change, outlines phases of the transition process, and considers the relationships between degrees of change and likely coping styles during the transition phases. Variables reflecting career motivation and situational support are predicted to affect the transition process under different degrees of change. The concepts discussed here can be used as a basis for diagnosing situational conditions and individual characteristics to design more effective learning methods in organizations.  相似文献   
88.
IntroductionTo ensure the quality of the new-born screening (NBS), our laboratory reviewed the analytical procedure to detect subjective steps that may represent a risk to the patient. Two subjective activities were identified in the extra-analytical phases: the classification of dried blood spots (DBS) according to their quality and the assignment of haemoglobin patterns. To keep these activities under control, inter-rater studies were implemented. This study aimed to evaluate the inter-rater reliability and the effectiveness of the measures taken to improve the agreement between observers, to assure NBS results’ quality.Materials and methodsDried blood spots specimens were used for the inter-rater studies. Ten studies were performed to assess DBS quality classification, and four to assess the assignment of haemoglobin patterns. Krippendorff’s alpha test was used to estimate inter-rater reliability. Causes were investigated when alpha values were below 0.80.ResultsFor both activities, the reliability obtained in the first studies was inadequate. After investigation, we detected that the criterion to classify a DBS as scant was not consolidated, and also a lack of consensus on whether or not to report Bart’s haemoglobin depending on its percentage. Alpha estimates became higher once the training was reinforced and a consensus about the appropriate criteria to be applied was reached.ConclusionInter-rater reliability assessment helped us to ensure the quality of subjective activities that could add variability to NBS results. Furthermore, the evolution of the alpha value over time allowed us to verify the effectiveness of the measures adopted.  相似文献   
89.
This paper reviews two recent research studies on Portuguese New Technology Based Firms (NTBFs). Attention is given to the role and contribution of NTBFs to innovation. The main argument is that, by and large, NTBFs are less concerned with the introduction of major innovations and more with creative adaptive improvements to products and services based upon new technologies first introduced elsewhere. The empirical research found that Portuguese NTBFs are a recent phenomenon associated with diffusion of Electronics and Information Technologies (EIT) during the late 1980s. They perform a wide variety of knowledge-intensive activities, which enhance local users' adoption processes and they are associated with different forms of technology transfer through external linkages. Overall, NTBFs undertake a frequently unobserved role as technology searchers and acquirers that, pushed by idiosyncratic local niche market opportunities, selectively choose among and enhance technologies developed elsewhere, introducing them into the local market.  相似文献   
90.
This paper examines the determination of wage rates for health professionals using three well known, and commonly used, econometric techniques: ordinary least squares, instrumental variables, and Heckman’s method. The data come from a graduate survey and the analysis focuses on a regional labor market, due to nationwide information on salaries is absent in Spain. After estimating different wage equations, the results suggest that OLS estimates are preferable. The findings show an important wage premium for medical doctors relative to nurses, but also a wage advantage for workers who are civil servants and a gender wage-gap that favors men. Although the expansion of higher education in Spain has reduced social inequalities in access, the main policy implication from this paper is that social class differences can still persist at the degree level—in the choice of degree—if students of higher socioeconomic status get a place at university in a degree of higher earnings, a fact that is corroborated in this study.  相似文献   
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