全文获取类型
收费全文 | 164篇 |
免费 | 5篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 20篇 |
金属工艺 | 6篇 |
机械仪表 | 2篇 |
建筑科学 | 5篇 |
矿业工程 | 2篇 |
轻工业 | 18篇 |
水利工程 | 2篇 |
无线电 | 3篇 |
一般工业技术 | 9篇 |
冶金工业 | 76篇 |
自动化技术 | 25篇 |
出版年
2022年 | 2篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2015年 | 2篇 |
2013年 | 19篇 |
2011年 | 2篇 |
2010年 | 5篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 5篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 16篇 |
1997年 | 5篇 |
1996年 | 7篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1983年 | 3篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 3篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1961年 | 2篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1956年 | 4篇 |
1955年 | 2篇 |
1954年 | 1篇 |
1944年 | 1篇 |
排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
In an effort to streamline the personal interview and to reduce the influence of subjectivity inpreparation of ranking lists for postgraduate year-one applicants, a standardized interview was constructed for use in evaluating condidates for admission to a training program in internal medicine. The interview was conducted in a uniformly structured manner by 14 interviewers of 260 applicants. Each applicant received an interview score which correlated well with the final decision of the Intern Selection Committee. For each interviewer various measures of performance were obtained which allowed a classification into "hard" versus "easy" interviewer and indicated the comparability of each interview's evaluations with the final decisions. Thus, the standardized interview resulted in quantifiable data in the form of uniform evaluations of applicants and interviewers. 相似文献
2.
Graph structure in the Web 总被引:11,自引:0,他引:11
Andrei Broder Ravi Kumar Farzin Maghoul Prabhakar Raghavan Sridhar Rajagopalan Raymie Stata Andrew Tomkins Janet Wiener 《Computer Networks》2000,33(1-6)
The study of the Web as a graph is not only fascinating in its own right, but also yields valuable insight into Web algorithms for crawling, searching and community discovery, and the sociological phenomena which characterize its evolution. We report on experiments on local and global properties of the Web graph using two AltaVista crawls each with over 200 million pages and 1.5 billion links. Our study indicates that the macroscopic structure of the Web is considerably more intricate than suggested by earlier experiments on a smaller scale. 相似文献
3.
4.
Vitamin B1 has been determined in a large number of beers by the fermentation method of Schultz, Atkin and Frey which has not previously been applied to worts and beers. In general, the highest amounts were found in beers of high original gravity and in those made almost entirely from malt. Well-attenuated and unprimed beers give the highest ratio, units of B1: calories. During the brew the malt, almost the sole source of vitamin B1, yields up the vitamin to the wort, which in its turn loses most of it to the yeast. Most of the vitamin B1 results have been confirmed by the thiochrome method involving an entirely different principle, whilst the general validity of both methods was further confirmed by animal feedings tests. Determination of Riboflavin (vitamin B2) by the microbiological method of Snell and Strong has led to the following conclusions:—Riboflavin is formed during germination of barley and in growing yeast. Most of the riboflavin of the malt passes into the wort during mashing and sparging and remains in the beer, the yeast not taking out any appreciable quantity. The number of microgrms. of riboflavin per 100 ml. of beer, in general, exceeds somewhat the number of degrees of original gravity. 相似文献
5.
6.
Efficiently identifying and quantifying disease- or treatment-related changes in the abundance of proteins is an important area of research for the pharmaceutical industry. Here we describe an automated, label-free method for finding differences in complex mixtures using complete LC-MS data sets, rather than subsets of extracted peaks or features. The method selectively finds statistically significant differences in the intensity of both high-abundance and low-abundance ions, accounting for the variability of measured intensities and the fact that true differences will persist in time. The method was used to compare two complex peptide mixtures with known peptide differences. This controlled experiment allowed us to assess the validity of each difference found and so to analyze the method's sensitivity and specificity. The method detects both presence versus absence and a 2-fold change in peptide concentration near the limit of detection of the instrument used, where chromatographic peaks may not be sufficiently well defined to be detected in individual samples. The method is more sensitive and gives fewer false positives than subtractive methods that ignore signal variability. Differential mass spectrometry combined with targeted MS/MS analysis of only identified differences may save both computation time and human effort compared to shotgun proteomics approaches. 相似文献
7.
Weizmann Fredric; Wiener Neil I.; Wiesenthal David L.; Ziegler Michael 《Canadian Metallurgical Quarterly》1990,31(1):1
Discusses J. P. Rushton's (see record 1986-17266-001) differential K theory (derived from the r/K model of evolutionary selection), which purportedly explains racial differences in sexual practices and anatomy, fertility, IQ, and criminality. The r/K model is frequently misinterpreted and overgeneralized. The predictions that Rushton derives from the r/K model are arbitrary, and these predictions are supported by selective citation and misrepresentation of the research literature and by the use of unreliable sources. Changes in human life-history traits are so rapid that there is no need to posit genetic selection to explain intergroup variation. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Dr Eng U. E. Wiener 《Measurement》1983,1(3):133-138
The presentation of the main results attained today in the field of metrological reliability must be preceded by isolating some principal problems. The first concerns the reliability of measurements and the reliability of measuring instruments, while the second concerns the definition of the metrological failure. The third problem is to do with the classification of characteristics of the metrological reliability.The paper will discuss that part of the metrological reliability which deals with the hardware, that is, with instrumental reliability. Basic models used in metrological reliability will be evaluated. A relevant aim of the paper is to describe the present state and to express some new ideas about the future development of metrological reliability. 相似文献
9.
10.
Gábor Wiener 《Algorithmica》2013,67(3):315-323
A set system $\mathcal{H} \subseteq2^{[m]}$ is said to be separating if for every pair of distinct elements x,y∈[m] there exists a set $H\in\mathcal{H}$ such that H contains exactly one of them. The search complexity of a separating system $\mathcal{H} \subseteq 2^{[m]}$ is the minimum number of questions of type “x∈H?” (where $H \in\mathcal{H}$ ) needed in the worst case to determine a hidden element x∈[m]. If we receive the answer before asking a new question then we speak of the adaptive complexity, denoted by $\mathrm{c} (\mathcal{H})$ ; if the questions are all fixed beforehand then we speak of the non-adaptive complexity, denoted by $\mathrm{c}_{na} (\mathcal{H})$ . If we are allowed to ask the questions in at most k rounds then we speak of the k-round complexity of $\mathcal{H}$ , denoted by $\mathrm{c}_{k} (\mathcal{H})$ . It is clear that $|\mathcal{H}| \geq\mathrm{c}_{na} (\mathcal{H}) = \mathrm{c}_{1} (\mathcal{H}) \geq\mathrm{c}_{2} (\mathcal{H}) \geq\cdots\geq\mathrm{c}_{m} (\mathcal{H}) = \mathrm{c} (\mathcal{H})$ . A group of problems raised by G.O.H. Katona is to characterize those separating systems for which some of these inequalities are tight. In this paper we are discussing set systems $\mathcal{H}$ with the property $|\mathcal{H}| = \mathrm{c}_{k} (\mathcal{H}) $ for any k≥3. We give a necessary condition for this property by proving a theorem about traces of hypergraphs which also has its own interest. 相似文献