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A systematic literature search was carried out to investigate the relationship between quick returns (i.e. 11.0 hours or less between two consecutive shifts) and outcome measures of health, sleep, functional ability and work–life balance. A total of 22 studies published in 21 articles were included. Three types of quick returns were differentiated (from evening to morning/day, night to evening, morning/day to night shifts) where sleep duration and sleepiness appeared to be differently affected depending on which shifts the quick returns occurred between. There were some indications of detrimental effects of quick returns on proximate problems (e.g. sleep, sleepiness and fatigue), although the evidence of associations with more chronic outcome measures (physical and mental health and work–life balance) was inconclusive.

Practitioner Summary: Modern societies are dependent on people working shifts. This study systematically reviews literature on the consequences of quick returns (11.0 hours or less between two shifts). Quick returns have detrimental effects on acute health problems. However, the evidence regarding effects on chronic health is inconclusive.  相似文献   

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Visible/near-infrared spectroscopy has been evaluated for use in freshness prediction and frozen-thawed classification of farmed Atlantic salmon fillets, where fresh samples were stored as whole fish in ice. A handheld interactance probe for performing rapid measurements of single fillets and an imaging spectrometer for online analysis at an industrial speed of one fillet per second, have been used. Freshness as storage days in ice is predicted with an accuracy of 2.4 days for individual fillets, whereas frozen-thawed salmon fillets are completely separated from fresh fillets. The prediction results are comparable to previous results using the Quality Index Method with trained panelists. The region between 605 and 735 nm, which excludes interference by carotenoids and water, is appropriate for both frozen-thawed classification and freshness prediction of salmon fillets. The results indicate that the spectral changes are explained mainly by oxidation of heme proteins during the freeze–thaw cycle and during chilled storage in ice.  相似文献   
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VIS/NIR spectroscopy for differentiating between fresh and frozen-thawed cod fillets and for assessing the freshness as days on ice has been evaluated. Both a handheld interactance probe for doing quick measurements of single fillets and an imaging spectrometer for doing online analysis at industrial speed of one fillet per second, have been used. Results show that frozen-thawed cod fillets can be fully separated from fresh fillets using a small subset of wavelengths in the visible region. Freshness as days on ice can be determined with an accuracy of 1.6 days on individual fillets. The results indicate that oxidation of hemoglobin and myoglobin during freezing-thawing and cold storage on ice are explaining most of the variations seen in the visible region of the spectrum.  相似文献   
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We show by simulation that when the fading signals observed on orthogonally polarized diversity branches follow Ricean statistics, the distribution of polarization states on the Poincar′e sphere is well-approximated by a Fisher distribution. Further, we show that the Fisher concentration parameter is: (1) completely determined by the corresponding Ricean Kfactors and the cross-correlation coefficient between the diversity branches, both of which can be estimated from simple measurements of received power vs. time, and (2) a good indicator of the level of cross-polar discrimination (XPD) on the channel. The insights gained are potentially useful to those engaged in the development and validation of schemes that use either polarization re-use or polarized MIMO.  相似文献   
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The musical group the Beatles had a profound impact on Western culture during their time together between 1960 and 1970. The three songwriters, John Lennon, Paul McCartney, and George Harrison, together and separately evolved in their lyrical styles over time. Using a new generation of computer text analyses, the Beatles' lyrics were analyzed to address how the group changed as a unit over time, how the various members changed in their writing styles, and the overlap in lyrical styles from one composer to the next. Overall, the Beatles' lyrics became darker, more psychologically distant, and less immediate over time. Paul McCartney's lyrical style proved to be more variable and broad ranging than either Lennon or Harrison. Using latent semantic analyses, Harrison's lyrics were more influenced by Lennon than by McCartney. Finally, the lyrics jointly written by Lennon and McCartney were mathematically more similar to Lennon's linguistic styles than McCartney's. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We observed temporal fading on 1.9 GHz fixed wireless channels during short-term measurements at 107 different locations in a suburban macrocell environment characterized by flat terrain and heavy foliage in order to determine how the rate of fading varies with average wind speed and distance. For each location, we estimated: (1) the Ricean K-factor using a momentbased estimator and (2) an equivalent Doppler frequency which is related to the maximum Doppler frequency by a factor that depends upon the shape of the Doppler spectrum. We did so by fitting the measured level crossing rate (LCR) and average fade duration (AFD) distributions to expressions normally justified for mobile wireless links using a method recently proposed by Feick, Valenzuela and Ahumada (2007). As has been observed at other sites, the Ricean K-factor decreased with both average wind speed and distance. However, we found that the equivalent Doppler frequency was effectively uncorrelated with wind speed and noticeably increased with distance. Similar measurements at other sites will be required to determine the extent to which these trends are affected by foliage density and tower height.  相似文献   
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ABSTRACT:  A promising method for detection of parasites in whitefish fillets has been developed. By use of imaging spectroscopy it is possible to record both spectral and spatial information from an object. In this work it is shown that by applying a white light transmission setup and imaging spectroscopy to cod ( Gadus morhua ) fillets, it is possible to make spectral images containing information to differentiate between fish muscle and parasites. The spectral images are analyzed by discriminant partial least square regression as well as image-filtering techniques. The method identifies parasites on the surface of the fillets as well as embedded parasites. One parasite was detected at 0.8 cm below the fillet surface, which is 2 to 3 mm deeper than what can be found by manual inspection of fish fillets. The method is nonintrusive and should thus be feasible for industrial purposes.  相似文献   
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OBJECTIVE: To examine what is attainable when treating urinary incontinence in women in general practice. DESIGN: Observational study with 12 months' follow up. Interview and clinical examination before, during, and after treatment of women seeking help for urinary incontinence in general practice. SETTING: General practice in the rural district of Rissa, Norway. SUBJECTS: 105 women aged 20 or more with urinary incontinence. INTERVENTIONS: Treatment with pelvic floor exercises, electrostimulation, oestrogen, anticholinergic drugs, bladder training, and protective pads. MAIN OUTCOME MEASURES: Subjective and objective measures of urinary incontinence; number of patients referred to a specialist. RESULTS: After 12 months' follow up 70% (69/99) of the women were cured or much better; the mean score on a 100 mm visual analogue scale decreased from 37 to 20 mm; and the proportion of women who were greatly bothered by their incontinence decreased by 62%. 20% (20/98) of women became continent, and the percentage of women with severe incontinence decreased from 64% (63/99) to 28% (27/98). Mean leakage per 24 hours measured by a pad test decreased from 28 g at the start of treatment to 13 g after 12 months. The number of light weight pads or sanitary towels decreased from 1.6 to 0.6 a day. In all, 17/105 (16%) patients were referred to a specialist. CONCLUSIONS: Urinary incontinence in women can be effectively managed in general practice with fairly simple treatment. Most women will be satisfied with the results.  相似文献   
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