全文获取类型
收费全文 | 352篇 |
免费 | 40篇 |
国内免费 | 45篇 |
专业分类
电工技术 | 23篇 |
综合类 | 48篇 |
化学工业 | 11篇 |
金属工艺 | 7篇 |
机械仪表 | 31篇 |
建筑科学 | 104篇 |
矿业工程 | 5篇 |
能源动力 | 4篇 |
轻工业 | 7篇 |
水利工程 | 3篇 |
石油天然气 | 4篇 |
武器工业 | 9篇 |
无线电 | 43篇 |
一般工业技术 | 32篇 |
冶金工业 | 12篇 |
原子能技术 | 1篇 |
自动化技术 | 93篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 14篇 |
2021年 | 18篇 |
2020年 | 14篇 |
2019年 | 22篇 |
2018年 | 20篇 |
2017年 | 26篇 |
2016年 | 13篇 |
2015年 | 21篇 |
2014年 | 30篇 |
2013年 | 31篇 |
2012年 | 28篇 |
2011年 | 18篇 |
2010年 | 19篇 |
2009年 | 17篇 |
2008年 | 13篇 |
2007年 | 25篇 |
2006年 | 15篇 |
2005年 | 9篇 |
2004年 | 14篇 |
2003年 | 8篇 |
2002年 | 13篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 7篇 |
1997年 | 6篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有437条查询结果,搜索用时 15 毫秒
421.
Image enhancement has been shown to improve the perceived quality of images and videos for people with visual impairments. The MPEG coding scheme makes spatial filtering, likely to help those with such impairments, possible at the decoding stage. We implemented a real-time platform for testing and improving contrast enhancement algorithms for MPEG video, with controls appropriate for the target population. The necessary additional processing runs efficiently on a general-purpose PC and can be integrated easily into existing MPEG-2 decoders. The system has enabled us to substantially improve the previous filtering algorithm; reducing artifacts exhibited in the previous implementation and should facilitate individual user-selection of enhancement parameters in evaluation studies. 相似文献
422.
Gerardo Brand Rihm Merlin Schueler Dr. Corina Nentwich Dr. Erik Esche Prof. Dr. Jens-Uwe Repke 《化学,工程师,技术》2023,95(7):1125-1133
In the absence of knowledge about challenging dynamic phenomena involved in batch distillation processes, e.g., complex flow regimes or appearing and vanishing phases, generation of accurate mechanistic models is limited. Real plant data containing this missing information is scarce, also limiting the use of data-driven models. To exploit the information contained in measurement data and a related but inaccurate first-principles model, transfer learning from simulated to real plant data is analyzed. For the use case of a batch distillation column, the adapted model provides more accurate predictions than a data-driven model trained exclusively on scarce real plant data or simulated data. Its enhanced convergence and lower computational cost make it suitable for optimization in real-time. 相似文献
423.
Due to the global spread of diseases and epidemics, the need to maintain a clean indoor atmosphere has received increasing attention in recent years. Therefore, there will be a need to clearly estimate and define the areas that affect human exposure to pollutants, taking into account the occupied density, which is the primary importance of this research. The capacity of the chilled ceiling combined with mixing ventilation and personal ventilation systems has been studied and compared to the chilled ceiling with mixing ventilation in terms of mean air age, temperature distribution, CO2 concentration, and thermal efficiency, with the best flow rate of the proposed system considering the occupied density in a thermally insulated office room experimentally in the climate of Iraq (Hilla, a hot and dry climate). Twelve tests were performed for four different cooling loads with cooled ceilings (0%, 0.25%, 50%, and 80%), at a constant supply air flow rate with two PV airflow modifiers for three cases. As the cooling load treated by a chilled ceiling increased, the average air temperature increased with height in all cases. The lowest values of average air age appeared in the occupied area in the case of a chilled ceiling with mixing ventilation. This study shows that the chilled ceiling combined with a mixing ventilation and personal ventilation system with a flow rate of 7.5 L/s provides thermal comfort and higher air quality in the occupied area. based on the values of air exchange efficiency and occupants’ air exchange efficiency. As a result, a flow rate of 7.5 L/s is the best option for protecting occupants from direct pollution in the breathing zone and in the surrounding microclimate, because the lower the ventilation rate, the less air is changed for occupants. 相似文献
424.
425.
Thuan-Quoc Thach Dhiya Mahirah Charlotte Sauter Adam Charles Roberts Gerard Dunleavy Nuraini Nazeha Yuri Rykov Yichi Zhang George I. Christopoulos Chee-Kiong Soh Josip Car 《Indoor air》2020,30(6):1166-1177
Indoor environmental quality (IEQ) is a general indicator of the quality of conditions inside a building. We investigated associations of perceived IEQ including air quality, thermal comfort, noise, and light quality with stress at work and the extent to which workplace location modifies these associations. We recruited 464 full-time workers from four companies in Singapore. Data on socio-demographic characteristics, lifestyle/health-related factors, and workplace factors were collected through self-administered questionnaires. Perceived IEQ satisfaction scores of all four factors were collected using the validated OFFICAIR questionnaire. We fitted a logistic regression model to assess associations between each perceived IEQ score and stress at work, adjusting for potential confounders. The odds ratio for stress at work associated with a 1-unit increase in perceived air quality score was 0.88 (0.82-0.94), 0.89 (0.82-0.97) for thermal comfort, 0.93 (0.87-0.98) for noise, and 0.88 (0.82-0.94) for light quality. Significant associations were found in office and control rooms for all four perceived IEQ, except for thermal comfort in office rooms. Higher satisfaction levels of perceived air quality, thermal comfort, noise, and lighting, were significantly associated with a reduction in stress at work. Our findings could potentially provide a useful tool for environmental health impact assessment for buildings. 相似文献
426.
This paper presents a review on thermal comfort research that is informed by changes in occupant behavior, lifestyle, and income leading to rebound or pre-bound effect. It explores the current state of research in thermal comfort domain through a systematic review to identify the gaps and opportunities specifically focusing on energy-intensive developing countries. This review argues that adaptive thermal comfort is a continuously evolving domain owing to dynamic modifications in occupant behavior occurring from changes in the cost of energy services and preference of comfort (rebound/pre-bound effect). A conceptual framework linking thermal comfort, rebound/pre-bound effect, and occupant behavior is forwarded through the introduction of an exogenous factor related to occupant well-being. The results ascertain that there is a need of localized thermal comfort model with an occupant-centric approach that can help in enhancing comfort and reducing energy consumption. 相似文献
427.
Solange Leder Jennifer A. Veitch Sandra Mancini Kate E. Charles 《Building Research & Information》2016,44(1):34-50
Two large and detailed field studies of the effect of office environment parameters on aspects of environmental and job satisfaction were conducted. The first study focused on open-plan offices in nine conventional buildings, whereas the second encompassed open-plan and private offices in 24 buildings (12 green and 12 conventional). The data collection for these studies was separated by approximately a decade, but the data collection methods, contexts and analysis procedures were very similar. This offered the opportunity to compare the results of the studies at the workstation level, with the goal of identifying parameters consistent in affecting occupant satisfaction, and of exploring the effects of office type (open-plan versus private) and building type (green versus conventional). Satisfaction with acoustics and privacy was most strongly affected by workstation size and office type; satisfaction with lighting was most strongly affected by window access and glare conditions; and satisfaction with ventilation and temperature was most strongly affected by pollutant concentration. Occupants of green buildings rated all aspects of environmental satisfaction more highly. Finally, job satisfaction was most strongly affected by pollutant concentration and office type. 相似文献
428.
Fourteen SAE standards related to accommodation and occupant packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationships of occupant packaging and ergonomics during the vehicle interior layout design and development are analyzed. Prototypes are presented to verify the results and how to achieve the packaging is shown. Automobile designers can achieve significant practical guidance for human safety, efficiency accommodation and occupant packaging of all passengers during the vehicle design process. 相似文献
429.
郑会保 《合成材料老化与应用》2014,(6):51-56
有机涂层的主要作用是保护金属不受腐蚀,然而,有机涂层在使用过程中经常受到太阳光、热和温度、水和湿气、氧和臭氧、污染物等的作用而产生老化现象,并伴随着各种性能的下降。论文综合论述了影响有机涂层老化的主要环境因素,以及为了模拟主要环境因素对涂层性能的影响而发展起来的试验室加速试验方法,近年来国内外发展起来的有机涂层自然环境适应性试验方法以及有机涂层老化性能检测、评价方法。 相似文献
430.
由于选择城市轨道交通工具出行的客流量的逐渐增加,车厢内的污染源增多,车厢内的空气环境逐渐成为人们关心的重要问题。本文以过渡季为基本背景,以上海市轨交系统九号线为实测对象,通过多轮次的现场连续实测,以此分析了地铁车厢内的空气环境,指出并讨论了车厢内空气热环境的几个基本特征。 相似文献