全文获取类型
收费全文 | 3742篇 |
免费 | 250篇 |
国内免费 | 154篇 |
专业分类
电工技术 | 106篇 |
综合类 | 344篇 |
化学工业 | 27篇 |
金属工艺 | 14篇 |
机械仪表 | 104篇 |
建筑科学 | 273篇 |
矿业工程 | 11篇 |
能源动力 | 15篇 |
轻工业 | 76篇 |
水利工程 | 21篇 |
石油天然气 | 17篇 |
武器工业 | 7篇 |
无线电 | 129篇 |
一般工业技术 | 472篇 |
冶金工业 | 1449篇 |
自动化技术 | 1081篇 |
出版年
2024年 | 10篇 |
2023年 | 68篇 |
2022年 | 96篇 |
2021年 | 139篇 |
2020年 | 104篇 |
2019年 | 114篇 |
2018年 | 92篇 |
2017年 | 106篇 |
2016年 | 115篇 |
2015年 | 96篇 |
2014年 | 148篇 |
2013年 | 177篇 |
2012年 | 181篇 |
2011年 | 269篇 |
2010年 | 216篇 |
2009年 | 295篇 |
2008年 | 236篇 |
2007年 | 256篇 |
2006年 | 210篇 |
2005年 | 226篇 |
2004年 | 210篇 |
2003年 | 181篇 |
2002年 | 155篇 |
2001年 | 119篇 |
2000年 | 47篇 |
1999年 | 19篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1996年 | 14篇 |
1995年 | 14篇 |
1994年 | 10篇 |
1993年 | 6篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1989年 | 6篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1985年 | 5篇 |
1966年 | 13篇 |
1965年 | 14篇 |
1964年 | 14篇 |
1963年 | 10篇 |
1961年 | 7篇 |
1960年 | 7篇 |
1959年 | 9篇 |
1958年 | 6篇 |
1957年 | 11篇 |
1956年 | 8篇 |
1955年 | 5篇 |
1954年 | 4篇 |
排序方式: 共有4146条查询结果,搜索用时 15 毫秒
1.
文章在对相关研究进行文献综述的基础上,以318国道川藏线为例,提出西部山地旅游公共服务5个维度的游客感知假设,选用偏最小二乘结构方程模型(PLS-SEM)对游客满意度组合模型进行因子分析与假设检验。根据模型拟合结果分析,旅游信息类公共服务在西部山地旅游公共服务中供需矛盾最为突出,其次为旅游交通类公共服务和旅游安全保障管理类公共服务,相对而言,旅游基础设施类公共服务和休闲空间与旅游便民惠民类公共服务供需矛盾较小。该结果为西部山地旅游公共服务体系构建明确了发展方向。 相似文献
2.
Hua Pang 《Telematics and Informatics》2018,35(8):2232-2241
Despite a substantial literature suggests that computer-mediated communication impact individuals’ various psychosocial factors, relatively few studies have elucidated the underlying mechanism behind these associations. Building upon self-disclosure theory and previous studies, the principal purpose of this present research is to systematically explore the relationships among microblog utilization, online self-disclosure, friendship maintenance, and perceived life satisfaction. A web-based survey was implemented using a total of 426 university students in Northwestern China. Structural equation modeling reveals that intensity of microblog use is positively associated with these students’ friendship maintenance and life satisfaction. Additionally, online self-disclosure plays the crucial mediatory role in the relationships between microblog use, quality of relationships, and gratification with life. The results imply that as microbloggers disclosure their inner thoughts or emotional states with other users online, they could foster their friendship maintenance and obtain greater life satisfaction. However, contrary to the expectation, students’ friendship maintenance is not discovered to be a significant predictor of the sense of life satisfaction in the online environment. Overall, these obtained outcomes of the empirical work could offer new insights into the deep comprehending of the social psychological process of microblogging among younger generation in the new media context. 相似文献
3.
4.
为了解18~45岁女性消费者在购买运动文胸时的情感偏好,以消费者在穿着体验中的评价为依据进行问卷调研,衡量消费者的情感偏好。通过探索性因子分析和验证性因子分析,构建5个一级指标和21个二级指标的消费者情感偏好评价指标模型,采用非线性主成分分析法确定影响消费者情感偏好设计要素的权重值。结果表明:一级指标权重值从大到小依次为面料(0.274)、色彩(0.191)、背部结构(0.188)、肩带形式(0.184)、罩杯形式(0.163),说明面料是消费者购买运动文胸时考虑的主要因素。 相似文献
5.
Trevor Sweetnam Michael Fell Eleni Oikonomou Tadj Oreszczyn 《Building Research & Information》2019,47(4):344-361
ABSTRACTElectric heat pumps feature prominently in projected energy transitions in the UK and elsewhere. Owing to their high electricity consumption, heat pumps are viewed as important targets for demand-side response (DSR). Findings are presented from a field trial of a new control system that aims to optimize heat pump performance, including under time-varying tariff conditions. The trial involved monitoring 76 properties with heat pumps, but without dedicated heat storage; 31 of these received the control system. Interviews were conducted with a subsample of 12 participants. The controller successfully evened out electricity demand over the day (reducing the evening peak), but this was associated with increased late night and daytime temperatures. Interview participants reported some disturbance owing to overnight heating and noise, as well as usability issues with the controller interface and hardware. These issues present risks to the future acceptability of such systems. While the system delivered short-term demand reductions successfully, longer-term demand shifting risked causing unacceptable disturbance to occupants. Future control systems could overcome some of the issues identified in this pioneering trial through more effective zoning, using temperature caps or installing dedicated heat storage, but these may either limit the available flexibility or be challenging to achieve. 相似文献
6.
针对电子商务顾客购物人工系统的计算实验研究,提出一种基于状态类比假说的人工情绪模型,给出了情绪的产生、增强、衰落和消失过程的描述方法,研究了外部刺激、情感强度和内部驱动力的计算方法,并进行了模拟分析。基于此人工情绪模型,构建了电商顾客购物的情绪-行为影响关系模型;将其应用于电商顾客购物的计算实验分析。结果表明,该人工情绪模型能较好地应用于电商复杂人工系统顾客购物的计算实验。 相似文献
7.
Occupants’ satisfaction had been researched independently related to thermal and visual stimuli for many decades showing among others the influence of self-perceived control. Few studies revealed interactions between thermal and visual stimuli affecting occupant satisfaction. In addition, studies including interactions between thermal and visual stimuli are lacking different control scenarios. This study focused on the effects of thermal and visual factors, their interaction, seasonal influences, and the degree of self-perceived control on overall, thermal, and visual satisfaction. A repeated-measures laboratory study with 61 participants running over two years and a total of 986 participant sessions was conducted. Mixed model analyses with overall satisfaction as outcome variable revealed that thermal satisfaction and visual satisfaction are the most important predictors for overall satisfaction with the indoor environment. Self-perceived thermal control served as moderator between thermal satisfaction and overall satisfaction. Season had slight influence on overall satisfaction. Random effects explained the highest amount of variance, indicating that intra- and interindividual differences in the ratings of satisfaction are more prevalent than study condition. Future building design and operation plans aiming at a high level of occupant satisfaction should consider personal control opportunities and take into account the moderating effect of control opportunities in multimodal interactions. 相似文献
8.
为了促进烟台葡萄酒文化旅游的发展,采用问卷调查与评分法,研究了消费者对烟台葡萄酒庄园文化旅游满意度和参与行为。结果表明,消费者对烟台葡萄酒庄园文化旅游满意度综合评分为39.31分,属极高水平;消费者对烟台葡萄酒庄园文化旅游5个评价指标满意度评分都超过4分,属于高满意度;消费者年龄与烟台葡萄酒庄园文化旅游满意度评分相关性并不显著;消费者学历与烟台葡萄酒庄园文化旅游满意度评分的相关性不显著。消费者获取葡萄酒文化旅游信息的渠道主要是网络、朋友介绍;消费者参与方式主要为家庭自驾,主要目的为观光、休息放松和科普教育。 相似文献
9.
Yajun Zhang Shan Liu Jing Tan Guoyin Jiang Qing Zhu 《International Journal of Project Management》2018,36(4):627-639
Although business process outsourcing (BPO) can reduce cost and enhance the competitiveness of firms, the implementation of BPO projects is unsatisfactory. By integrating knowledge management capability theory and risk-based view, we develop a model of how different types of BPO risks affect project satisfaction and how knowledge management capability changes the influences of BPO risks. A survey of 121 BPO projects was conducted among BPO client department manager and project manager through a pairwise design. Empirical evidence reveals that social system, technical system, and project management risks negatively affect BPO project satisfaction. However, cultural, technological, and structural levels of knowledge management capabilities weaken the negative risk effects of social system, technical system, and project management, respectively. Different types of risks and knowledge management capabilities should be matched to achieve effective risk management. 相似文献
10.
Multiemotional product color design using gray theory and nondominated sorting genetic algorithm-III
When users select products, they consider the emotional experience resulting from the color of the product. However, the emotional demands of users for product color are multidimensional and diverse. It is very important yet difficult to accurately grasp multiemotional image requirements and effectively convert them into design elements. Therefore, multiemotional product color design (MEPCD) has become a very important and challenging research topic. In this article, a novel MEPCD system using gray theory (GT) and nondominated sorting genetic algorithm-III (NSGA-III) is proposed to effectively solve the MEPCD problem. First, the image perception spaces of users, which exist in different emotional dimensions, were collected using factor analysis and the semantic differential technique. Then, GT was used to establish a multidimensional emotional product color image evaluation model. Finally, NSGA-III was used to optimize and design a multiemotional color scheme for a product. Furthermore, according to actual conditions, an MEPCD system was established based on the proposed method. The design case study shows that the method and design system proposed in this article have a certain range of applicability and can effectively improve the practicality of MEPCD. 相似文献