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1.
2.
A key challenge faced by organizations is to provide project teams with workspaces, information, and collaboration technologies
that fosters creativity and high-performance team productivity. This requires understanding the relation between and impacts
of (1) workspace, (2) activity and content that is created, and (3) social, behavioral, and cognitive aspects of work. This
paper describes an exploratory study of everyday activities in the context of knowledge work in a shared workspace used by
a high-tech global design team that explores future products. The study formalizes key elements for productive knowledge work
as a function of tasks, context, and team. It identifies enablers, hindrances, and requirements for physical, virtual, and
social work environments. The study identified, through semi-structured interviews, surveys, and on-site shadowing, a key
workspace component that facilitates dynamic participation of all team members. This workspace component is a wall used as
a large, public, physical display surface for project content (the WALL). The WALL acts as a mediator for individual reflection-in-action
and team reflection-in-interaction. It serves as “social glue” both between individuals and between geographically distributed
subgroups. 相似文献
3.
We explore in this paper the relation between activities, communication channels and media, and common ground building in
global teams. We define re-representation as a sequence of representations of the same concept using different communication
channels and media. We identified the re-representation technique to build common ground that is used by team members during multimodal and multimedia communicative events in cross-disciplinary,
geographically distributed settings. Our hypotheses are as follows: (1) Significant sources of information behind decisions
and request for actions are embedded within the fabric of communicative events in which participants use both informal and
formal media to express their ideas. Capturing these information sources can facilitate common ground building and accelerate
the execution of action requests. (2) Re-representations of concepts, i.e., sequences of representations using diverse media
and communication channels, mediate and accelerate common ground building. (3) The use of intra- or interdisciplinary re-representations
correlates with high team performance, i.e., effective team process and high product quality. We used AEC Global Teamwork
course offered in 2008–2009 as the testbed for our study to validate our hypothesis. 相似文献
4.
Synthesis of 2,4-Bisalkyl(aryl)amino-6-cyanamino-s-triazines Reaction of 2,4-bisalkyl(aryl)amino-6-chloro-s-triazines with disodiumcyanamide to 2,4-bisalkyl(aryl)amino-6-cyanamino-s-triazines ( 3a – g ) strongly depends on the solvent used. In dimethylformamide by-products predominate. The best results are found in dimethylsulphoxide. 相似文献
5.
Marceau Kristine; Ram Nilam; Houts Renate M.; Grimm Kevin J.; Susman Elizabeth J. 《Canadian Metallurgical Quarterly》2011,47(5):1389
Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear mixed-effects models to describe both the timing and tempo of pubertal development in the sample of 364 White boys and 373 White girls measured across 6 years as part of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Individual differences in timing and tempo were extracted with models of logistic growth. Differential relations emerged for how boys' and girls' timing and tempo of development were related to physical characteristics (body mass index, height, and weight) and psychological outcomes (internalizing problems, externalizing problems, and risky sexual behavior). Timing and tempo are associated in boys but not girls. Pubertal timing and tempo are particularly important for predicting psychological outcomes in girls but only sparsely related to boys' psychological outcomes. Results highlight the importance of considering the nonlinear nature of puberty and expand the repertoire of possibilities for examining important aspects of how and when pubertal processes contribute to development. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
6.
Jan T. Svensson Justyna J. Olas Renate Skibior Henriette Giese Andreas Blennow 《Starch - St?rke》2012,64(7):563-571
We investigated the growth behavior and amylolytic enzymes of Fusarium graminearum cultivated on different types of native starch granules including barley (A‐type crystalline polymorph), potato and Curcuma zedoaria (B‐type crystalline polymorph), cassava (C‐type crystalline polymorph), and high AM maize (A + Vh‐type crystalline polymorphs). F. graminearum grew poorly on B‐type starches and the accumulation of biomass was similar to that obtained for fungi cultivated under carbohydrate starvation conditions. In comparison, three‐ to fivefold higher accumulation of fungal biomass was observed for growth on the A‐, C‐ and A + Vh‐type starches. Fungal glucoamylase and α‐amylase activity increased over time in the presence of native starch granules. Interestingly, resistant B‐type starches induced the highest amylolytic activity indicating that F. graminearum interacts with B‐type granules although only limited degradation occur. Starch degradation products maltose and malto‐oligosacharides was found to increase glucoamylase and α‐amylase activity, whereas glucose acted as a catabolite repressor. 相似文献
7.
Predictions of financial time series often show a characteristic one step shift relative to the original data as in a random walk. This has been the cause for opposing views whether such time series do contain information that can be extracted for predictions, or are simply random walks. In this case study, we show that NNs that are capable of extracting weak low frequency periodic signals buried in a strong high frequency signal, consistently predict the next value in the series to be the current value, as in a random walk, when used for one-step-ahead predictions of the detrended S&P 500 time series. In particular for the Time Delay Feed Forward Networks and Elman Networks of various configurations, our study supports the view of the detrended S&P 500 being a random walk series. This is consistent with the long standing hypothesis that some financial time series are random walk series. 相似文献
8.
The receptor tyrosine kinase, KIT, displays activating mutations in the kinase domain, which are associated with various cancers. We have used homology modelling based on the crystal structures of the insulin receptor kinase in active and inactive conformations to predict the corresponding structures of the KIT kinase domain. We have prepared four KIT models, one each for the active and inactive conformations of the wild-type and of the Asp816Val mutant proteins. We have also placed ATP into the active conformations and the inhibitor, STI571, into the inactive conformations. All models have been fully energy minimised. The molecular modelling studies described here explain (i) why Asp816Val KIT is constitutively active, (ii) why the nature of the substituting amino acid at residue 816 is relatively unimportant, and (iii) why the Asp816Val substitution confers resistance to the KIT-inhibitory drug STI571. The models will be valuable for predicting other kinase inhibitory drugs that may be active on wild-type and mutant forms of KIT. During the course of this work, a crystal structure of the active conformation of the KIT kinase domain has been published. Our model of the active conformation of the Asp816Val mutant is strikingly similar to this crystal structure, whereas our model of the active conformation of the wild-type kinase domain of KIT differs from the crystal structure in some respects. The reasons for this apparent discrepancy are discussed. 相似文献
9.
10.
We present a two-sorted algebra, called aPeirce algebra, of relations and sets interacting with each other. In a Peirce algebra, sets can combine with each other as in a Boolean algebra, relations can combine with each other as in a relation algebra, and in addition we have both a set-forming operator on relations (the Peirce product of Boolean modules) and a relation-forming operator on sets (a cylindrification operation). Two applications of Peirce algebras are given. The first points out that Peirce algebras provide a natural algebraic framework for modelling certain programming constructs. The second shows that the so-calledterminological logics arising in knowledge representation have evolved a semantics best described as a calculus of relations interacting with sets. 相似文献