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1.
Adherence to pharmacologic therapy of hypertension is low (in the range of 50-70%) and has important implications both for blood pressure control and cardiovascular complications. Based on a review of the literature using the levels of evidence grading technique, determinants of adherence to the pharmacologic therapy of hypertension have been assessed. Additionally, interventions to improve compliance were evaluated. Patient-centred, health care provider-centred and drug-specific factors have all been shown to affect adherence rates. We conclude that the extent of adherence to pharmacologic therapy is modifiable. Measurable improvements in adherence can be obtained from simplified medication regimens and a combination of behaviour strategies, including the tailoring of pill-taking to patients' daily habits and rituals, the advocacy of self-monitoring of pills and blood pressure, and the institution of reward systems.  相似文献   
2.
Conducted a comprehensive meta-analysis based on 665 validity coefficients across 576,460 data points to investigate whether integrity test validities are generalizable and to estimate differences in validity due to potential moderating influences. Results indicate that integrity test validities are substantial for predicting job performance and counterproductive behaviors on the job, such as theft, disciplinary problems, and absenteeism. The estimated mean operational predictive validity of integrity test for predicting supervisory ratings of job performance is .41. Results from predictive validity studies conducted on applicants and using external criterion measures (i.e., excluding self-reports) indicate that integrity tests predict the broad criterion of organizationally disruptive behaviors better than they predict employee theft alone. Despite the influence of moderators, integrity test validities are positive across situations and settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Comments on W. J. Camara and D. L. Schneider's (see record 1994-23870-001) summary of reports on integrity tests (ITs). It is argued that in reviewing empirical findings about the validity of ITs, they overlooked critical findings regarding how well they work and what they measure. Also, their concerns regarding research on ITs conducted by test publishers are unfounded. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Response bias continues to be the most frequently cited criticism of personality testing for personnel selection. The authors meta-analyzed the social desirability literature, examining whether social desirability functions as a predictor for a variety of criteria, as a suppressor, or as a mediator. Social desirability scales were found not to predict school success, task performance, counterproductive behaviors, and job performance. Correlations with the Big Five personality dimensions, cognitive ability, and years of education are presented along with empirical evidence that (a) social desirability is not as pervasive a problem as has been anticipated by industrial-organizational psychologists, (b) social desirability is in fact related to real individual differences in emotional stability and conscientiousness, and (c) social desirability does not function as a predictor, as a practically useful suppressor, or as a mediator variable for the criterion of job performance. Removing the effects of social desirability from the Big Five dimensions of personality leaves the criterion-related validity of personality constructs for predicting job performance intact. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
The throughput performance of a wireless media access protocol taking into account the effect of correlated channel fading, capture, and propagation delay is analyzed. For efficient access on the uplink (mobile-to-base-station link), the protocol makes use of the uplink channel status information which is conveyed to the mobiles through a busy/idle flag broadcast on the downlink (base-station-to-mobile link). A first-order Markov model is used to describe the correlation in the packet success/failure process on a Rayleigh-fading channel. The analytical results obtained through the first-order Markov approximation of the channel are compared to those obtained from an independent and identically distributed (i.i.d.) channel model. The Markovian-fading channel model is shown to provide better performance results than the i.i.d. channel model. Simulations show that a first-order Markov approximation of the Rayleigh-fading process is quite accurate. An enhanced version of the access protocol to take advantage of the memory in the fading channel behavior is proposed and analyzed. The effect of retransmission of erroneous data packets and propagation delay on the throughput is also analyzed. It is shown that the access protocol with an error detect (ED) feature is efficient in slow fading (e.g., pedestrian user speeds), whereas a retransmission protocol is more efficient in fast fading (e.g., vehicular user speeds)  相似文献   
6.
Abnormalities of the sex ratio of births may be linked with environmental factors, including diet and pollutants in the general or occupational environments, which in turn can cause ill-health. To examine this relationship in the Province of Newfoundland and Labrador, where a geographical imbalance of mortality has already been identified, we examined the geographical distribution of sex ratios (boys/girls x 100) of young children (0-4 years) in the communities of the Province during recent years. The individual communities of the 1976 and 1981 censuses were assigned to contiguous regions and their component districts. The numbers in the appropriate age-groups in the communities in these two census years were used to calculate a mean sex ratio for each community; each community was allocated, according to the value of its ratio, to one of four predefined categories of ratio. From the numbers of communities belonging to these various categories of sex ratio in the regions and districts, the community sex ratios of these areas (i.e. regions and districts) were derived. As a preliminary assessment of the relationship between sex ratios and mortality, a small group of communities with the highest sex ratios was selected, and the mean standardized mortality ratios (SMRs) for all deaths in those communities were calculated. The community sex ratios of regions and districts declined from east to west. The difference in the ratios between the Avalon region (in the most easterly part of the Province) and the southwest region was statistically significant. Districts with high ratios were frequent, particularly those on the Avalon peninsula in the south-east of the island, whereas low ratios were more frequent on the south-west coast of the island, and a low ratio was also found for the only inland district. Of the communities with statistically reliable numbers, the township of Makkovik in Labrador had the highest sex ratio (100 x 50/25 = 200). The SMR of that community during 1976-82 was statistically elevated at 218. In the small group of communities studied, however, high sex ratios from census data for individual communities were not reliable predictors of high SMRs. Further work is required to clarify the inter-relationships between the sex ratios of the census data, the sex ratios of births, the mortality rates and environmental factors.  相似文献   
7.
The efficacy and safety of optimally titrated once-daily (CD) and twice-daily (SR) diltiazem were compared in 111 patients with mild to moderate systemic hypertension [seated diastolic blood pressure (DBP) > or = 95 mmHg and < or = 114 mmHg] in a multicenter, randomized, double-blind, placebo run-in, parallel-group trial. Following a 4 week washout and placebo-controlled run-in period, patients were randomized to receive diltiazem CD 180 mg and matching placebo (n = 54), or diltiazem SR 90 mg bid (n = 57). Total daily doses were titrated from 180 mg to 360 mg to achieve a goal of seated DBP < 90 mmHg during a 6 week titration period. The patients continued to receive their optimal dose for a 6 week follow-up period. Ninety-six (96) patients (diltiazem CD: 47, diltiazem SR: 49) completed the study protocol, with 60% of the diltiazem CD and 55% of the diltiazem SR patients achieving the goal of seated DBP of < 90 mmHg (p = 0.685). Although significant decreases occurred in seated and standing measurements of diastolic and systolic BP and heart rate with treatment in both groups, there were no significant differences between treatment groups. Both medications were well tolerated, with a similar frequency of adverse effects [diltiazem CD: 24/54 (37%) patients; diltiazem SR: 24/57 (42.1%) patients] with the most frequently reported adverse effects being headache and edema.  相似文献   
8.
Solar still is a simple device which can convert available waste or brackish water into potable water using solar energy. A single basin double slope solar still with an inner basin size 2.08 m × 0.84 m × 0.075 m and that of the outer basin size 2.3 m × 1 m × 0.25 m has been fabricated with mild steel plate and tested with a layer of water and different sensible heat storage materials like quartzite rock, red brick pieces, cement concrete pieces, washed stones and iron scraps. It is found that, the still with ¾ in. sized quartzite rock is the effective basin material. The still is theoretically modeled. In previous researcher’s work, variation in transmittance is taken as constant. The variations in solar incidence angle and transmittance of the covers are also considered in this work. The theoretical values are compared with actual values. The theoretical water and glass temperatures and the theoretical production rate are having higher deviation with actual. Hence, another thermal model developed for this still is applied to validate the results accurately. It is found that, the theoretical production rate using thermal model agrees well with experimental.  相似文献   
9.
Single basin solar still is a very simple solar device used for converting available brackish or waste water into potable water. This device can be fabricated easily with locally available materials. The maintenance is also cheap and no skilled labor is required. This device can be a suitable solution to solve drinking water problem. Because of its low productivity it is not popularly used. Numbers of works are undertaken to improve the productivity of the still. In this work progresses in the works done on single basin passive types still to improve its productivity are reviewed. The orientation and inclination are optimized to receive maximum radiation and lower the condensation loss. Different materials are used in the basin along with water to improve the heat capacity, radiation absorption capacity and enhance the evaporation rate. Rubber is the best basin material to improve absorption, storage and evaporation effects. The effect of varying the depth of the basin water is also studied.  相似文献   
10.
Phase transformation, microstructure development and mechanical properties of 2.45 GHz microwave-sintered silicon nitride (Si3N4) with lithium yttrium oxide (LiYO2) and zirconia (ZrO2) sintering additives were investigated. It was found that α to β phase transformation completed at a lower temperature of 1500 °C. Scanning electron microscopy (SEM) micrographs revealed a bimodal microstructure with a large number of elongated β-Si3N4 grains in addition to smaller grains. Surface residual porosity was observed in all sintered samples due to selective localized over heating of grain-boundary glassy phase. The high aspect-ratio of β-Si3N4 grains exhibited significant crack deflection, debonding and pull-out. It was observed that Vickers hardness and indentation fracture toughness increased with increasing sintering temperature.  相似文献   
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