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91.
92.
Studies have documented a link between distracted driving and diminished safety; however, an association between distracted driving and traffic congestion has not been investigated in depth. The present study examined the behavior of teens and young adults operating a driving simulator while engaged in various distractions (i.e., cell phone, texting, and undistracted) and driving conditions (i.e., free flow, stable flow, and oversaturation). Seventy five participants 16–25 years of age (split into 2 groups: novice drivers and young adults) drove a STISIM simulator three times, each time with one of three randomly presented distractions. Each drive was designed to represent daytime scenery on a 4 lane divided roadway and included three equal roadway portions representing Levels of Service (LOS) A, C, and E as defined in the 2000 Highway Capacity Manual. Participants also completed questionnaires documenting demographics and driving history. Both safety and traffic flow related driving outcomes were considered. A Repeated Measures Multivariate Analysis of Variance was employed to analyze continuous outcome variables and a Generalized Estimate Equation (GEE) Poisson model was used to analyze count variables. Results revealed that, in general more lane deviations and crashes occurred during texting. Distraction (in most cases, text messaging) had a significantly negative impact on traffic flow, such that participants exhibited greater fluctuation in speed, changed lanes significantly fewer times, and took longer to complete the scenario. In turn, more simulated vehicles passed the participant drivers while they were texting or talking on a cell phone than while undistracted. The results indicate that distracted driving, particularly texting, may lead to reduced safety and traffic flow, thus having a negative impact on traffic operations. No significant differences were detected between age groups, suggesting that all drivers, regardless of age, may drive in a manner that impacts safety and traffic flow negatively when distracted.  相似文献   
93.
Soy isoflavone consumption appears to be beneficial for several health parameters. We report the influence of (lifelong exposure to) a high soy/isoflavone (High-Iso) compared to a low soy/isoflavone (Low-Iso) diet on body weight (BW), white adipose tissue (WAT) deposition, prostate weight (PW), testicular weight (TW), and testosterone levels in young adult male Long-Evans rats. WAT deposition and the WAT/BW ratios were significantly less in High-Iso vs. the Low-Iso fed animals. TW and TW/BW ratios were significantly greater in High-Iso vs. Low-Iso fed animals. Sertoli cell area, seminiferous tubule lumens and seminiferous tubule areas were significantly greater in High-Iso vs. Low-Iso animals. These data suggest that consumption of a soy diet high in isoflavone/polyphenolic molecules from conception appear to be beneficial in decreasing PW and WAT deposition while increasing TW, Sertoli cell area and seminiferous tubule volume.  相似文献   
94.
Sodium nitrite (NaNO2) is used as a curing agent in frankfurters. Although previous studies have documented the bacteriostatic abilities of NaNO2 toward Listeria monocytogenes, few if any studies have been conducted that consider the possibility of sublethal injury to L. monocytogenes by exposure to NaNO2. The goals of this study were to determine whether NaNO2 has the ability to injure L. monocytogenes, to determine whether nitrite injury is reversible, and to compare the recovery of L. monocytogenes from frankfurters containing nitrite with Listeria repair broth (LRB) and University of Vermont modified Listeria enrichment broth (UVM). NaNO2, when used at concentrations of 100 and 200 ppm, was found to injure L. monocytogenes. The injury was completely reversible, or growth of uninjured Listeria occurred in LRB when injury was between 98.5 and 98.7%. However, total recovery was not observed in LRB when injury exceeded 99%. UVM was unable to reverse the effects of nitrite-injured L. monocytogenes. With respect to time, inoculum, and meat type, LRB was found to be consistently superior to UVM at recovering L. monocytogenes from frankfurters. Nitrite injury might be a factor influencing detection and recovery of L. monocytogenes from frankfurters.  相似文献   
95.
This study investigates the relationships between loneliness, anxiousness, alcohol, and marijuana use in the prediction of freshman college students’ connections with others on the social network site Facebook as well as their emotional connectedness to Facebook. A survey of 229 respondents was conducted at a mid-sized public university to examine these relationships. Respondents were currently living in university dormitories and had an active Facebook account. The study examined the aforementioned predictor variables in relation to Facebook connections strategies and emotional connectedness to Facebook. Results showed that anxiousness, alcohol use, and marijuana use predicted emotional attachment to Facebook. Additionally, loneliness and anxiousness, but not alcohol or marijuana use, predicted individuals’ connections with others using Facebook. The current study adds to the growing body of literature investigating predictors of why individuals become emotionally attached to Facebook and the precursors to connecting with others on Facebook.  相似文献   
96.
Over the past decade, the role of multiangle remote sensing has been central to the development of algorithms for the retrieval of global land surface properties including models of the bidirectional reflectance distribution function (BRDF), albedo, land cover/dynamics, burned area extent, as well as other key surface biophysical quantities impacted by the anisotropic reflectance characteristics of vegetation. In this study, a new retrieval strategy for fine-to-moderate resolution multiangle observations was developed, based on the operational sequence used to retrieve the Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 5 reflectance and BRDF/albedo products. The algorithm makes use of a semiempirical kernel-driven bidirectional reflectance model to provide estimates of intrinsic albedo (i.e., directional-hemispherical reflectance and bihemispherical reflectance), model parameters describing the BRDF, and extensive quality assurance information. The new retrieval strategy was applied to NASA's Cloud Absorption Radiometer (CAR) data acquired during the 2007 Cloud and Land Surface Interaction Campaign (CLASIC) over the well-instrumented Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site in Oklahoma, USA. For the case analyzed, we obtained ~ 1.6 million individual surface bidirectional reflectance factor (BRF) retrievals, from nadir to 75° off-nadir, and at spatial resolutions ranging from 3 m to 500 m. This unique dataset was used to examine the interaction of the spatial and angular characteristics of a mixed agricultural landscape; and provided the basis for detailed assessments of: (1) the use of a land cover type-specific a priori knowledge in kernel-driven BRDF model inversions; (2) the interaction between surface reflectance anisotropy and instrument spatial resolution; and (3) the uncertainties that arise when sub-pixel differences in the BRDF are aggregated to a moderate resolution satellite pixel. Results offer empirical evidence concerning the influence of scale and spatial heterogeneity in kernel-driven BRDF models; providing potential new insights into the behavior and characteristics of different surface radiative properties related to land/use cover change and vegetation structure.  相似文献   
97.
The deletion of matrix metalloproteinase MMP9 is combined here with chronic monocular deprivation (cMD) to identify the contributions of this proteinase to plasticity in the visual system. Calcium imaging of supragranular neurons of the binocular region of primary visual cortex (V1b) of wild-type mice revealed that cMD initiated at eye opening significantly decreased the strength of deprived-eye visual responses to all stimulus contrasts and spatial frequencies. cMD did not change the selectivity of V1b neurons for the spatial frequency, but orientation selectivity was higher in low spatial frequency-tuned neurons, and orientation and direction selectivity were lower in high spatial frequency-tuned neurons. Constitutive deletion of MMP9 did not impact the stimulus selectivity of V1b neurons, including ocular preference and tuning for spatial frequency, orientation, and direction. However, MMP9−/− mice were completely insensitive to plasticity engaged by cMD, such that the strength of the visual responses evoked by deprived-eye stimulation was maintained across all stimulus contrasts, orientations, directions, and spatial frequencies. Other forms of experience-dependent plasticity, including stimulus selective response potentiation, were normal in MMP9−/− mice. Thus, MMP9 activity is dispensable for many forms of activity-dependent plasticity in the mouse visual system, but is obligatory for the plasticity engaged by cMD.  相似文献   
98.
Objective: Despite being a voluntary activity, many blood donors experience anxiety, and fainting (syncope) is not unusual. The muscle-tensing technique applied tension (AT) has been found to be effective in reducing vasovagal symptoms and syncope. A series of studies was developed to investigate the role of AT on anxiety and fainting. Methods: The mechanisms of AT were examined in the laboratory and the blood donor clinic. In Study 1, 70 participants were assigned randomly to either a control group or an experimental group who learned AT before watching a video depicting blood draws. In Study 2, 667 volunteer blood donors completed similar questionnaires. Results: In Study 1, a significant Condition × Sex × Needle Fear interaction, F(1, 59)=4.97, p=.03, indicated that AT reduced vasovagal symptoms in higher-fear women. Study 2 also found a significant Condition × Sex × Needle Fear effect on vasovagal symptoms, F(2, 653)=3.95, p=.02, indicating that AT reduced symptoms but primarily among women with more pronounced fear of needles. Conclusions: Analysis of the physiological data and self-reported anxiety supports the conclusion that the reduction in vasovagal symptoms was due more to decreased anxiety rather than exercise-related cardiovascular change. These results suggest that AT may provide a useful means of coping with invasive medical procedures in part by reducing anxiety. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
99.
Transparent conducting molybdenum-doped zinc oxide (MZO) films were successfully prepared by radio frequency (RF) magnetron sputtering method on glass substrates under different substrate temperatures. The nature of MZO film is polycrystalline with hexagonal structure and a preferred orientation along c-axis. With increasing substrate temperature from room temperature to 400°C, the crystallinity of the films is deteriorated and the resistivity increases sharply due to both the decrease of carrier concentrat...  相似文献   
100.
Previous research has demonstrated that the experience of reading e-books is not equivalent to reading textbooks. This study examines factors influencing preference for e-books as well as reported use of e-book content. Although the present student cohort is the most technologically savvy to ever enter universities, students do not prefer e-books over textbooks regardless of their gender, computer use or comfort with computers. No significant correlations existed between the number of e-books previously used and overall preference of e-books: Participants who had previously used an e-book still preferred print texts for learning. Despite the ability to easily access supplemental content through e-books via hyperlinks and other features, students were more likely to use special features in print books than in e-books.  相似文献   
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