全文获取类型
收费全文 | 1405篇 |
免费 | 33篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 26篇 |
化学工业 | 229篇 |
金属工艺 | 22篇 |
机械仪表 | 22篇 |
建筑科学 | 22篇 |
矿业工程 | 5篇 |
能源动力 | 39篇 |
轻工业 | 132篇 |
水利工程 | 10篇 |
石油天然气 | 3篇 |
无线电 | 124篇 |
一般工业技术 | 180篇 |
冶金工业 | 470篇 |
原子能技术 | 7篇 |
自动化技术 | 149篇 |
出版年
2021年 | 9篇 |
2019年 | 12篇 |
2018年 | 12篇 |
2017年 | 13篇 |
2016年 | 19篇 |
2015年 | 11篇 |
2014年 | 16篇 |
2013年 | 49篇 |
2012年 | 25篇 |
2011年 | 50篇 |
2010年 | 45篇 |
2009年 | 46篇 |
2008年 | 50篇 |
2007年 | 47篇 |
2006年 | 43篇 |
2005年 | 32篇 |
2004年 | 33篇 |
2003年 | 36篇 |
2002年 | 26篇 |
2001年 | 27篇 |
2000年 | 16篇 |
1999年 | 32篇 |
1998年 | 106篇 |
1997年 | 87篇 |
1996年 | 42篇 |
1995年 | 41篇 |
1994年 | 33篇 |
1993年 | 39篇 |
1992年 | 32篇 |
1991年 | 19篇 |
1990年 | 16篇 |
1989年 | 21篇 |
1988年 | 18篇 |
1987年 | 23篇 |
1986年 | 18篇 |
1985年 | 20篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 20篇 |
1981年 | 17篇 |
1980年 | 17篇 |
1979年 | 13篇 |
1978年 | 9篇 |
1977年 | 16篇 |
1976年 | 44篇 |
1975年 | 24篇 |
1974年 | 15篇 |
1973年 | 9篇 |
1972年 | 9篇 |
1971年 | 9篇 |
排序方式: 共有1440条查询结果,搜索用时 31 毫秒
1.
Storage performance-metrics and benchmarks 总被引:2,自引:0,他引:2
Chen P.M. Patterson D.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1993,81(8):1151-1165
The metrics and benchmarks used in storage performance evaluation are discussed. The technology trends taking place in storage systems, such as disk and tape evolution, disk arrays, and solid-state disks, are highlighted. The current popular I/O benchmarks are then described, reviewed, and run on three systems: a DECstation 5000/200 running the Sprite Operating System, a SPARCstation 1+ running SunOS, and an HP Series 700 (Model 730) running HP-UX. Two approaches to storage benchmarks-LADDIS and a self-scaling benchmark with predicted performance-are also described 相似文献
2.
DJ Patterson 《Canadian Metallurgical Quarterly》1994,23(2):313-325
Postgastrectomy syndromes are uncommon but, unfortunately, frustrating for both patient and physician, because treatment with prokinetic agents is often of limited benefit. This article examines the evidence for efficacy of available prokinetic drugs in the management of these difficult disorders. 相似文献
3.
Steven Y. Susswein Thomas C. Henderson Joseph L. Zachary Chuck Hansen Paul Hinker Gary C. Marsden 《International journal of parallel programming》1991,20(6):453-473
Filtering algorithms are well accepted as a means of speeding up the solution of the consistent labeling problem (CLP). Despite the fact that path consistency does a better job of filtering than arc consistency, AC is still the preferred technique because it has a much lower time complexity. We are implementing parallel path consistency algorithms on multiprocessors and comparing their performance to the best sequential and parallel arc consistency algorithms.(1,2) (See also work by Kerethoet al.
(3) and Kasif(4)) Preliminary work has shown linear performance increases for parallelized path consistency and also shown that in many cases performance is significantly better than the theoretical worst case. These two results lead us to believe that parallel path consistency may be a superior filtering technique. Finally, we have implemented path consistency as an outer product computation and have obtained good results (e.g., linear speedup on a 64K-node Connection Machine 2). 相似文献
4.
Hovius Marjolijn; Kellenbach Marion L.; Graham Kim S.; Hodges John R.; Patterson Karalyn 《Canadian Metallurgical Quarterly》2003,17(1):100
The authors investigated the impact of semantic knowledge on visual object analysis by assessing the performance of patients with semantic dementia on a different-views object matching test and on 2 object decision tests differing, for example, in whether the nonreal items were nonsense objects or chimeras of 2 real objects. On average, the patients scored normally on both the object matching and the object decision test including nonsense objects but were impaired on the object decision test including chimeras; this latter was also the only visual object test that correlated significantly with degree of semantic impairment. These findings demonstrate that object decision is not a single task or ability and that it is not necessarily independent of conceptual knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Emily S. Patterson David D. Woods Richard I. Cook Marta L. Render 《Cognition, Technology & Work》2007,9(3):155-162
Resilience, the ability to adapt or absorb disturbance, disruption, and change, may be increased by team processes in a complex,
socio-technical system. In particular, collaborative cross-checking is a strategy where at least two individuals or groups
with different perspectives examine the others’ assumptions and/or actions to assess validity or accuracy. With this strategy,
erroneous assessments or actions can be detected quickly enough to mitigate or eliminate negative consequences. In this paper,
we seek to add to the understanding of the elements that are needed in effective cross-checking and the limitations of the
strategy. We define collaborative cross-checking, describe in detail three healthcare incidents where collaborative cross-checks
played a key role, and discuss the implications of emerging patterns. 相似文献
6.
SK Patterson JA Tworek MA Roubidoux MA Helvie HA Oberman 《Canadian Metallurgical Quarterly》1997,169(3):709-712
OBJECTIVE: The objective of this study was to describe the mammographic appearance with pathologic correlation of metaplastic carcinoma of the breast. CONCLUSION: Metaplastic carcinomas of the breast are masses with mammographic characteristics of low suspicion because of their histologic appearance. Metaplastic carcinoma should be included in the differential assessment of predominately circumscribed, noncalcified masses revealed on mammography. One salient feature that may distinguish metaplastic carcinomas is the occurrence of a circumscribed portion with a spiculated portion, which is seen in carcinomas that have a significant mixture of metaplastic and invasive carcinoma growth patterns. 相似文献
7.
Chuck Sins 《电子设计应用》2007,(4):I0009-I0009,I0011,I0013,I0015
信号路径的设计为系统设计工程师提供不少可供他们发挥的机会.以设有模拟/数字转换器的信号路径为例来说,工程师进行设计时不但要为传感器提供缓冲,而且还要解决模拟/数字转换器开关电容的输入充电问题,以及要尽量减少系统的噪音源,只要构思的设计能解决这些问题,便可大幅提升系统的性能.今期的信号路径设计专辑将会深入讨论这方面的问题. 相似文献
8.
Shubneesh Batra Nanseng Jeng Akif Sultan Kyle Picone Surya Bhattacharya Keun-Hyung Park Sanjay Banerjee David Kao Monte Manning Chuck Dennison 《Journal of Electronic Materials》1993,22(5):551-554
When dopants are indiffused from a heavily implanted polycrystalline silicon film deposited on a silicon substrate, high thermal
budget annealing can cause the interfacial “native” oxide at the polycrystalline silicon-single crystal silicon interface
to break up into oxide clusters, causing epitaxial realignment of the polycrystalline silicon layer with respect to the silicon
substrate. Anomalous transient enhanced diffusion occurs during epitaxial realignment and this has adverse effects on the
leakage characteristics of the shallow junctions formed in the silicon substrate using this technique. The degradation in
the leakage current is mainly due to increased generation-recombination in the depletion region because of defect injection
from the interface. 相似文献
9.
General issues relating to the use of outcome and process data from the treatment of antisocial children to predict future childhood adjustment are examined. For outcome measures, it was assumed that variables based on direct observation of child behavior would provide a better predictor of long-term adjustment than would ratings by participant adults. Long-term adjustment measures consisted of police arrest and out-of-home placement data collected 2 years after treatment termination. Observation data collected at termination predicted future police arrest, but parent and teacher ratings did not. It was also hypothesized that measures of the processes thought to produce the changes in child antisocial behavior would serve as predictors of future adjustment. The data supported this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Simple pseudo-steady state relations between the hydraulic and nozzle pressures of an injection molding machine were presented and verified experimentally. A simulation study was performed to evaluate the performance of simple controllers using dynamic models developed for the hydraulic and nozzle pressures. The controllers chosen were the discrete proportional, proportional-integral (PI), and proportional-integral-derivative (PID) types, tuned according to the ITAE criterion. The control of hydraulic pressure simulation showed that the PI controller had the best overall performance, whereas the result of nozzle pressure control loop simulation showed that the PID controller performance was better than that of the PI controller. All the controllers, in both loops, gave responses that were about an order of magnitude more rapid than the open loop response. 相似文献