全文获取类型
收费全文 | 372篇 |
免费 | 10篇 |
国内免费 | 16篇 |
专业分类
电工技术 | 6篇 |
综合类 | 15篇 |
化学工业 | 4篇 |
金属工艺 | 3篇 |
机械仪表 | 4篇 |
建筑科学 | 30篇 |
矿业工程 | 2篇 |
能源动力 | 1篇 |
轻工业 | 6篇 |
石油天然气 | 2篇 |
无线电 | 25篇 |
一般工业技术 | 12篇 |
冶金工业 | 65篇 |
原子能技术 | 1篇 |
自动化技术 | 222篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 5篇 |
2020年 | 16篇 |
2019年 | 7篇 |
2018年 | 16篇 |
2017年 | 11篇 |
2016年 | 21篇 |
2015年 | 8篇 |
2014年 | 17篇 |
2013年 | 21篇 |
2012年 | 21篇 |
2011年 | 33篇 |
2010年 | 25篇 |
2009年 | 23篇 |
2008年 | 27篇 |
2007年 | 17篇 |
2006年 | 21篇 |
2005年 | 21篇 |
2004年 | 8篇 |
2003年 | 18篇 |
2002年 | 20篇 |
2001年 | 6篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1994年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1964年 | 4篇 |
1963年 | 1篇 |
1961年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有398条查询结果,搜索用时 15 毫秒
61.
Giorgina Barbara Piccoli Gabriella Guzzo Federica Neve Vigotti Irene Capizzi Roberta Clari Stefania Scognamiglio Valentina Consiglio Emiliano Aroasio Silvana Gonella Andrea Veltri Paolo Avagnina 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):590-595
Renal function recovery (RFR), defined as the discontinuation of dialysis after 3 months of replacement therapy, is reported in about 1% of chronic dialysis patients. The role of personalized, intensive dialysis schedules and of resuming low‐protein diets has not been studied to date. This report describes three patients with RFR who were recently treated at a new dialysis unit set up to offer intensive hemodialysis. All three patients were females, aged 73, 75, and 78 years. Kidney disease included vascular‐cholesterol emboli, diabetic nephropathy and vascular and dysmetabolic disease. At time of RFR, the patients had been dialysis‐dependent from 3 months to 1 year. Dialysis was started with different schedules and was progressively discontinued with a “decremental” policy, progressively decreasing number and duration of the sessions. A moderately restricted low‐protein diet (proteins 0.6 g/kg/day) was started immediately after dialysis discontinuation. The most recent update showed that two patients are well off dialysis for 5 and 6 months; the diabetic patient died (sudden death) 3 months after dialysis discontinuation. Within the limits of small numbers, our case series may suggest a role for personalized dialysis treatments and for including low‐protein diets in the therapy, in enhancing long‐term RFR in elderly dialysis patients. 相似文献
62.
共识机制是区块链技术的重要组成部分,但是主流的共识机制尤其是工作量证明共识机制都存在算力过度耗费和吞吐量低等问题. 而联邦学习作为一种分布式机器学习方法,学习模型的本地训练和最终的参与方贡献度计算都需要消耗大量算力资源. 因此,提出了一种支持自适应联邦学习任务的可信公平区块链框架TFchain,探索如何利用原本共识机制中耗费的大量算力来提高联邦学习的效率. 首先,设计了基于区块链和联邦学习的全新共识机制PoTF(proof of trust and fair),该共识机制将区块链的节点设置为联邦学习的参与方,将原本共识机制中用于哈希计算的大量无效算力转移到联邦学习中,进行本地模型的训练和参与方贡献度的评估;其次,在提高区块链交易吞吐量的同时,对联邦学习的参与方进行了合理的贡献度评估和激励;最后,设计了防止节点作恶的算法. 实验结果表明,提出的TFchain能够在回收算力的同时有效提升区块链的交易处理性能,对积极参与联邦学习的参与方进行有效正向的激励.
相似文献63.
基于模糊理论的因特网个性化服务应用 总被引:6,自引:0,他引:6
为了使因特网上的服务更加有效和便利,以Web挖掘为基础的因特网个性化服务目前正在得到广泛的研究和应用。本文以模糊理论为基础,探讨了一个基于Web日志挖掘的个性化用户预测系统。 相似文献
64.
传统的矩阵分解法只能简单提取低阶信息,特征组合单一,无法挖掘更多隐含信息.依赖稀疏的评分表已经无法满足个性化推荐.MovieLens数据集是研究推荐系统的经典数据集.通过改进神经协同过滤模型,使用多个嵌入层对MovieLens数据集所有信息进行嵌入分析,充分挖掘隐含信息,使得推荐算法更有实用意义.通过在MovieLen... 相似文献
65.
The effect of facially applied air movement on perceived air quality (PAQ) at high humidity was studied. Thirty subjects (21 males and 9 females) participated in three, 3-h experiments performed in a climate chamber. The experimental conditions covered three combinations of relative humidity and local air velocity under a constant air temperature of 26 °C, namely: 70% relative humidity without air movement, 30% relative humidity without air movement and 70% relative humidity with air movement under isothermal conditions. Personalized ventilation was used to supply room air from the front toward the upper part of the body (upper chest, head). The subjects could control the flow rate (velocity) of the supplied air in the vicinity of their bodies. The results indicate an airflow with elevated velocity applied to the face significantly improves the acceptability of the air quality at the room air temperature of 26 °C and relative humidity of 70%. 相似文献
66.
The present experiments extend the temporal discounting paradigm from choice between an immediate and a delayed reward to choice between 2 delayed rewards: a smaller amount of money available sooner and a larger amount available later. Across different amounts and delays, the data were consistently well described by a hyperbola-like discounting function, and the degree of discounting decreased systematically as the delay to the sooner reward increased. Three theoretical models (the elimination-by-aspects, present-value comparison, and common-aspect attenuation hypotheses) were evaluated. The best account of the data was provided by the common-aspect attenuation hypothesis, according to which the common aspect of the choice alternatives (i.e., the time until the sooner reward is available) receives less weight in the decision-making process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Sharp Elizabeth C.; Pelletier Luc G.; Lévesque Chantal 《Canadian Metallurgical Quarterly》2006,38(3):269
This quasi-experimental study examined participation rates and sample characteristics of participants recruited with and without the offer of course credit. In Sample 1, where course credit is not usually offered, credit was added in one condition (N = 195) and not in the other (N = 175). In Sample 2, where credit is usually offered, it was maintained in one condition (N = 92) and removed in the other (N = 178). Results in both samples revealed that participation rates were higher in the credit conditions; they plunged when customary rewards were taken away. Results also revealed evidence of sample bias. More specifically, the motivational characteristics of participants and nonparticipants differed in all conditions except the new credit condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Research has consistently found that the decline in the present values of delayed rewards as delay increases is better fit by hyperbolic than by exponential delay-discounting functions. However, concave utility, transaction costs, and risk each could produce hyperbolic-looking data, even when the underlying discounting function is exponential. In Experiments 1 (N=45) and 2 (N=103), participants placed bids indicating their present values of real future monetary rewards in computer-based 2nd-price auctions. Both experiments suggest that utility is not sufficiently concave to account for the superior fit of hyperbolic functions. Experiment 2 provided no evidence that the effects of transaction costs and risk are large enough to account for the superior fit of hyperbolic functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Recent theories of job satisfaction generally assume 2 underlying types of job elements important to employee satisfaction: those in the work process which allow for self-actualization, and environmental elements in which the worker's rewards are physical and monetary. A parallel assumption pertains to the 2 types of employees for whom each of these is important. A validation of such constructs was attempted through factor analysis and indicated 3 underlying groups of job elements important to job satisfaction: social and technical environment, intrinsic work aspects, and recognition through advancement. The factor of greatest import to each employee was identified, and factored groups of employees were described in terms of their differing age, salary, and occupational patterns. No significant differences in overall job satisfaction among the 3 groups were found. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
An experiment to test the hypothesis that psychopathy is associated with deficient passive avoidance learning under punishment. 75 High Pd and 75 Low Pd female undergraduates, equated for intelligence, learned a list of 10 nonsense syllables under 1 of 3 conditions of reinforcement: verbal reward, verbal punishment, and absence of comment by E. Punishment significantly retarded the learning of Low Pd Ss, but not that of High Pd Ss. No significant differences occurred under reward or neutral conditions. The hypothesis was considered confirmed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献