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81.

Background

Reports of a relationship between watching smoking in movies and smoking among adolescents have prompted greater scrutiny of smoking in movies by the public health community.

Objective

To assess the smoking prevalence among adult and adolescent movie characters, examine trends in smoking in movies over time, and compare the data with actual smoking prevalence among US adults and adolescents.

Design and methods

Smoking status of all major human adolescent and adult movie characters in the top 100 box office hits from 1996 to 2004 (900 movies) was assessed, and smoking prevalence was examined by Motion Picture Association of America (MPAA) rating and year of release.

Results

The movies contained 5944 major characters, of whom 4911 were adults and 466 were adolescents. Among adult movie characters, the overall smoking prevalence was 20.6%; smoking was more common in men than in women (22.6% v 16.1%, respectively, p<0.001), and was related to MPAA rating category (26.9% for movies rated R (restricted, people aged <17 years require accompanying adult), 17.9% for PG‐13 (parents strongly cautioned that some material might be inappropriate for children) and 10.4% for G/PG (general audiences, all ages; parental guidance suggested for children), p<0.001). In 1996, the smoking prevalence for major adult movie characters (25.7%) was similar to that in the actual US population (24.7%). Smoking prevalence among adult movie characters declined to 18.4% in 2004 (p for trend <0.001), slightly below that for the US population for that year (20.9%). Examination of trends by MPAA rating showed that the downward trend in smoking among adult movie characters was statistically significant in movies rated G/PG and R, but not in those rated PG‐13. A downward trend over time was also found for smoking among adolescent movie characters. There was no smoking among adult characters in 43.3% of the movies; however, in 39% of the movies, smoking prevalence among adult characters was higher than that in the US adult population in the year of release.

Conclusions

Smoking prevalence among major adolescent and adult movie characters is declining, with the downward trend among adult characters weakest for PG‐13‐rated movies. Although many movies depict no adult smoking, more than one third depict smoking as more prevalent than that among US adults at the time of release.Recent research has established that there is an association between watching smoking in movies and smoking among adolescents.1,2,3,4,5,6,7 This has prompted greater scrutiny of the movie industry by the public health community,8 and has highlighted the need to understand better how and why smoking is depicted in movies. As smoking among movie characters considerably influences smoking among youths, the public health community needs data on its frequency and reach. Just as quantitative measures of smoking among the general population are used to assess the effectiveness of public health campaigns on smoking, quantitative measures could be used to assess the success of public health campaigns aimed at reducing depictions of smoking in movies. Smoking in movies is generally quantified through content analysis, in which a specified sample frame of movies is assessed according to a set of predefined criteria. Previous studies generally agree that (1) smoking is depicted in most movies9,10,11,12,13,14,15; (2) smoking in movies increases as Motion Picture Association of America rating increases from G to R9,14,15; (3) movie characters who smoke do not represent the typical smoker (in that they are more likely to be affluent, good looking and powerful than are typical smokers)9,12; and (4) smoking in movies is rarely depicted in the context of negative health outcomes.9,10,12,15Content analyses vary in the way they quantify movie smoking, and this makes it difficult to compare results across studies. One objective measure of smoking in movies is the smoking prevalence among major characters. This type of assessment requires coders to determine the number of major characters (however this is defined) and also to determine whether or not each character is depicted as a smoker. The overall smoking prevalence among characters and yearly time trends can then be determined, as can prevalence rates by movie and character traits (eg, sex or age). Although the smoking prevalence among characters has not been measured in all content analyses, it is reported in many of them, and is remarkably consistent. McIntosh et al13 reported a smoking rate of 21% among characters in films released in the 1980s. Dalton et al9 and Omidvari et al16 reported rates of 25% and 21%, respectively, for movies released in the 1990s. We report time trends for smoking prevalence among adult and adolescent movie characters for the top 100 US box office hits released over a 9‐year period to better understand recent trends in smoking among movie characters.  相似文献   
82.
Over many years the use of composite structures in aerospace and automobile applications has been expanding. Thus, the study of weaknesses associated with composite materials has become paramount. Delamination is a fundamental concern with these structures, and mixed mode strain energy release rates are valuable information for analysing delamination cracks. The localised experimental–numerical technique (LENT), which measures local test displacement data and combines this with local finite element analysis to evaluate the mixed mode strain energy release rates, is examined via extensive experimental testing and analysis to provide validation for the technique. Additionally, a sensitivity analysis is presented to assess the influence of pixel size on the strain energy release rate results determined using LENT. Enhancements to the method are presented focusing on reducing the pixel size and improving post-processing techniques for increased accuracy. Variations in the local area analysed with LENT are also investigated. The results demonstrate that the localised experimental–numerical technique has potential for the evaluation of mixed mode strain energy release rates using localised test data.  相似文献   
83.
This experiment investigated the effects of choice and response format on children's search of informational text. We compared the information-seeking performance of 42 Grade 3 children who were given a choice of books with 42 children who were not given a choice. Half of the children in the choice and no-choice conditions were instructed to record their answers on a theme board, and half were instructed to write their answers on a work sheet. Children were randomly assigned to the following conditions: (a) choice–theme board, (b) choice–work sheet, (c) no-choice–theme board, and (d) no-choice–work sheet. Prior knowledge and topic interest were included as covariates. Choice of topic facilitated both performance and process measures, whereas response format affected process measures only. Prior knowledge emerged as a significant contributor to accuracy and time to locate information. Children's text search was affected by choice and context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
An approach to producing hierarchical multi-scale porous ultra-high temperature ceramics (zirconium diboride, ZrB2) using 3D printing has been developed. Porous ceramic filaments can be 3D printed via Direct Ink Writing (DIW) (paste extrusion). Millimeter scale porosity is created by the 3D printed scaffold filaments. We introduce 20-micron-scale porosity into the scaffold filaments with the addition of oil to produce capillary suspension paste inks. Micron-scale porosity is also developed by partial sintering of the ceramic. The rheological (flow) properties of the capillary suspension paste inks suitable for printing by extrusion through the needle of the 3D printer have been characterized. The samples are strengthened by partial sintering at high temperatures. Complex-shaped components can be printed and sintered into crack-free components, but distortion during drying and sintering lead to poor shape and tolerance control. X-ray tomography is used to characterize the internal structure of the printed components. Printed test bars measured in 4-point bend testing exhibit high strength to density ratio. Such materials potentially have applications as insulation near very high-temperature surfaces in aerospace applications.  相似文献   
85.
Value creation in all its facets lies at the core of intelligent manufacturing and engineering. In the last 20 years the field of manufacturing has undergone many changes and refinements. Terms such as Integrated Management Systems (IMS), Just in Time (JIT), Toyota Production System (TPS) in the context of Lean Production and ‘Flow’ were parts of the toolset developed by the Toyota Corporation which pushed them to the forefront of world automotive production. While benchmarking the design production systems and their associated efficiencies is very worthwhile, there are other engineering design, lean production, just in time, and production and supply chain exemplars which are worth investigating. A primary source of best-practice engineering in flexible and intelligent manufacturing is to be found in the study of ‘Bionics’ (Biomimicry). The intelligence in design and operational efficiency which is brought to Bionics by design in nature was recognised by Leonardo DaVinci when he wrote: “… in her (design) nothing is lacking and nothing is superfluous” [1]… This paper examines how design and engineering can learn and apply through the study of bionics/biomimicry, a vast pool of knowledge of design and systems engineering strategies. Such strategies and exemplars will provide benchmarks which will result in inspirational approaches in design, efficiency and sustainable engineering solutions.  相似文献   
86.
The use of omni-directional cameras has become increasingly popular in vision systems for video surveillance and autonomous robot navigation. However, to date most of the research relating to omni-directional cameras has focussed on the design of the camera or the way in which to project the omni-directional image to a panoramic view rather than the processing of such images after capture. Typically images obtained from omni-directional cameras are transformed to sparse panoramic images that are interpolated to obtain a complete panoramic view prior to low level image processing. This interpolation presents a significant computational overhead with respect to real-time vision. We present an efficient design procedure for space variant feature extraction operators that can be applied to a sparse panoramic image and directly processes this sparse image. This paper highlights the reduction of the computational overheads of directly processing images arising from omni-directional cameras through efficient coding and storage, whilst retaining accuracy sufficient for application to real-time robot vision.
Dermot KerrEmail:
  相似文献   
87.
A miniature electrostatic thruster is being developed in Low Temperature Co‐fired Ceramic (LTCC) at Boise State University. The thruster is composed of an antenna to create the plasma, a cylinder to contain the plasma, and grids to extract the plasma beam at high velocity. In this work, the development of the inductively coupled plasma (ICP) antenna in LTCC will be presented. This antenna is fabricated using DuPont 951 LTCC tape. A Direct Write dispenser is used to apply silver paste for the spiral ICP antenna. Using LTCC allows for the antenna to be embedded in the device under a thin sheet of LTCC dielectric, which protects the antenna from ion back bombardment during operation. This thin sheet is the seventh layer of the total device, with the ICP antenna one layer below the top. The design of the antenna is based on the research done by J. Hopwood. This article discusses the fabrication and performance of the ICP antennas in LTCC. These ICP antennas are operated at pressures from 10 mTorr to 1 Torr with radio frequencies (RF) of 500 MHz to 1 GHz to inductively couple with low‐pressure argon to produce plasma. The performance of the antennas will be verified with data showing the start and stop power of the plasma at various pressures and an electric field map of the RF field above the antenna.  相似文献   
88.
Over the last ten years there have been reports of pharmaceuticals and personal care product (PPCP) residuals in municipal wastewater treatment plant (WWTP) effluents. The principle goal of this study was specifically to expand and in some cases establish a Canadian database for the presence of selected acidic drugs, triclosan, polycyclic musks, and selected estrogens in MWWTP influent and effluent. The impact of treatment configuration (e.g. lagoons, conventional activated sludge (CAS), and CAS followed by media filtration (CAS+filtration)) was also examined. For CAS systems, the most prevalent treatment type, the effect of operating temperature and SRT was evaluated. Selected PPCPs included ten acidic pharmaceuticals (i.e. a group of pharmaceuticals that are extractable at a pH of 2 or less), triclosan, five polycyclic musks and two estrogens. The pharmaceuticals and musks were selected on the basis of levels of use in Canada; reported aquatic toxicity effects; and the ability to analyze for the compounds at low levels. Twelve MWWTPs discharging into the Thames River, the second largest river in southwestern Ontario, were surveyed. The only common characteristic of acidic drugs is their extraction pH as they differ in their intended biological function and chemical structure. Many organics degraded by WWTP processes benefit from warm temperatures and long SRTs so the impact of these variables warranted additional attention. Influent concentrations and reductions for acidic drugs reported by this study were compared to other Canadian studies, when available, and European investigations. The data of this study seems consistent with other reports. Ten acidic drugs were considered by this study. Three were consistently present at non-quantifiable levels (e.g. CLF, FNP and FNF). Additionally, one analyte, SYL, presented results that were so inconsistent that the values were not analysed. The remaining six acidic pharmaceuticals were placed into three categories. IBU and NPX members of the first category had consistently high reductions. At the level of reduction achieved (i.e. median reduction of greater than 93%) and any effect of treatment type or operating characteristics would be subtle and non-discernable given the analytical noise. In the second group are KTP and IND, and definitive comments are difficult to make on the impact of treatment type and operational considerations due to a sparse data set (i.e. many influent values were at non-quantifiable concentrations). Median reductions were in the 23% to 44% range. In the last category are GMF and DCF which have median reductions of 66% and -34%, respectively. Several negative reduction values in the data set (i.e. twelve of twenty six sampling events) suggest that DCF may be deconjugated under certain conditions. This warrants further evaluation when analytical methods for measuring human metabolites of DCF are available. For both GMF and DCF, reduction does not appear to be strongly influenced by SRTs up to 15 days, while SRTs over 30 days were associated with more frequent non-quantifiable effluent levels of DCF. This would suggest that better treatment would be provided by lagoons and CAS systems with extended aeration. Preliminary data suggests that temperature does not play a strong role in the reduction of these compounds. Triclosan (TCL) was detected at concentrations of 0.01-4.01 microg/L in influent samples and 0.01-0.324 microg/L in effluent samples. Reduction of TCL ranged from 74% to 98%. Lagoon treatment seems to be the best TCL reduction as it was present in the influent and effluent at quantifiable and non-quantifiable concentrations, respectively, on nine of nine sampling occasions. Influent and reduction values of five polycyclic musks (e.g. ADBI, AHMI, ATII, HHCB, and AHTN) were examined over the course of this study. AHMI was predominantly present at non-quantifiable concentrations. HHCB and AHTN were present at the highest concentrations. A comparison between Canadian values and those of European studies indicate that in general polycyclic musk concentrations in Canadian MWWTP effluents are 5-10 times lower. More extensive European and Canadian databases would be useful in confirming this initial observation. Median reductions for the five remaining musks range between 37% and 65% in CAS systems. CAS+filtration systems would be expected to have higher reductions if musks were bound to the effluent solids. This trend is not apparent but this may be due to the small size of the data set. In lagoon systems, musk reduction for HHCB and AHTN are approximately 98-99%. For ADBI and ATII musk, there are no numerical reduction values as most often the effluent concentration was non-quantifiable. In some instances, both the influent and effluent concentrations were non-quantifiable. The hormones 17-beta-estradiol (E2) and estrone (E1) were detected at concentrations of 0.006 to 0.014 and 0.016 to 0.049 microg/L, respectively. E2 was not detected in any effluent samples (<0.005 microg/L) whereas E1 was detected in effluent samples from CAS treatment plants (median of 0.008 microg/L), and in one sample from lagoons. These data demonstrate that there are detectable levels of PPCPs entering Canadian waterways at trace levels, and that only some of these compounds are being reduced in a significant proportion by municipal wastewater treatment processes.  相似文献   
89.
Novel bacterial (HT) and fungal (FPII) food‐grade protease preparations were evaluated for their ability to hydrolyse sheep cheese whey (SCW) and the generation of bioactive peptides. Both protease preparations hydrolysed the whey proteins to small peptides over 24‐h hydrolysis time, but the time course hydrolysis profiles were different as evaluated by SDS‐PAGE. The HT whey hydrolysate had considerably higher antioxidant and angiotensin‐I converting enzyme (ACE)‐inhibitor activity than the FPII hydrolysate. Neither hydrolysate was cytotoxic towards Vero cells. OFFGEL electrophoresis of the small peptide pool fraction (<15 amino acids) of each hydrolysate indicated differences in the pI distribution of the bioactive peptides. This likely reflects the diverse hydrolytic specificity of the proteases. Although the antioxidant activity of both hydrolysates was not significantly affected by simulated gastrointestinal digestion, the loss of ACE‐inhibitor activity was greater with the FPII hydrolysate.  相似文献   
90.
Parental affect and coping strategies have been identified as being important for the understanding of the processes involved in the socialization of children. In the present study, 24 fathers (mean age 35.21 yrs old) and 62 mothers (mean age 35.05 yrs) (unrelated) described a stressful incident with one of their children and completed questionnaires addressing their appraisal of the event, their affect, and consequent coping strategy. Both child characteristics (age, birth order, and gender) and parent characteristics (gender, affect intensity, and ego level) were examined in relation to parents' appraisal of the cause of the event, their affect, and their coping strategy. Feelings of being angry, afraid, sad, and guilty, and use of coping strategies are discussed in light of the need for further research on emotion in parenting situations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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