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1.
按照当前的技术水准,如果设计一个不与网络或互联网连接的控制、调节或数据通信系统显然是落伍了。文中将介绍如何采用Maxim/Dalias创新的八位网络微控制器DS80C400实现低成本的具有WEB连接的工业应用。  相似文献   
2.
This paper reports on an aspect of the EC funded Argunaut project which researched and developed awareness tools for moderators of online dialogues. In this study we report on an investigation into the nature of creative thinking in online dialogues and whether or not this creative thinking can be coded for and recognized automatically such that moderators can be alerted when creative thinking is occurring or when it has not occurred after a period of time. We outline a dialogic theory of creativity, as the emergence of new perspectives from the interplay of voices, and the testing of this theory using a range of methods including a coding scheme which combined coding for creative thinking with more established codes for critical thinking, artificial intelligence pattern-matching techniques to see if our codes could be read automatically from maps and ‘key event recall’ interviews to explore the experience of participants. Our findings are that: (1) the emergence of new perspectives in a graphical dialogue map can be recognized by our coding scheme supported by a machine pattern-matching algorithm in a way that can be used to provide awareness indicators for moderators; (2) that the trigger events leading to the emergence of new perspectives in the online dialogues studied were most commonly disagreements and (3) the spatial representation of messages in a graphically mediated synchronous dialogue environment such as Digalo may offer more affordance for creativity than the much more common scrolling text chat environments. All these findings support the usefulness of our new account of creativity in online dialogues based on dialogic theory and demonstrate that this account can be operationalised through machine coding in a way that can be turned into alerts for moderators.  相似文献   
3.
Methods for standardized classification of epileptic seizures are important for both clinical practice and epidemiologic research. In this study, we developed a strategy for standardized classification using a semistructured telephone interview and operational diagnostic criteria. We interviewed 1,957 adults with epilepsy ascertained from voluntary organizations. To confirm and expand the seizure history, we also interviewed a first-degree relative for 67% of subjects and obtained medical records for 59%. Three lay reviewers used all available information to classify seizures. To assess reliability, each reviewer classified a sample of subjects assigned to the others. In addition, an expert physician classified a sample of subjects assigned to two of the reviewers. Agreement was "moderate-substantial" for generalized-onset seizures, both for the comparisons between pairs of lay reviewers and for the neurologist versus lay reviewers. Agreement was "substantial-almost perfect" for partial-onset seizures, both for pairs of lay reviewers and for the neurologist versus lay reviewers. These results suggest that seizures can be reliably classified by lay reviewers, using operational criteria applied to symptoms ascertained in a semistructured telephone interview.  相似文献   
4.
5.
The sodium channel initiates action potentials by opening in response to membrane depolarization. Fast channel inactivation, which is required for proper physiological function, is mediated by a cytoplasmic loop proposed to occlude the ion pore via a hinged lid mechanism with the triad IFM serving as a hydrophobic "latch". The NMR solution structure of the isolated inactivation gate reveals a stably folded core comprised of an alpha-helix capped by an N-terminal turn, supporting a model in which the tightly folded core containing the latch motif pivots on a more flexible hinge region to occlude the pore during inactivation. The structure, in combination with substituted cysteine mutagenesis experiments, indicates that the IFM triad and adjacent Thr are essential components of the latch and suggests differing roles for the residues of the IFMT motif in fast inactivation.  相似文献   
6.
One phase of an ongoing program aimed at developing an all-electronic control system for a home appliance is described. The shortcomings of conventional electromechanical motor-starting systems and problems in the early design stages of a replacement electronic system are discussed. A circuit which automatically adjusts itself to compensate for changing conditions so that it always provides the correct motor starting action is presented. Broader applications of the unique circuit are discussed.  相似文献   
7.
Sacoglossans are a group of opisthobranch mollusks that have been the source of numerous secondary metabolites; however, there are few examples where a defensive ecological role for these compounds has been demonstrated experimentally. We investigated the deterrent properties of the sacoglossan Elysia rufescens and its food alga Bryopsis sp. against natural fish predators. Bryopsis sp. produces kahalalide F, a major depsipeptide that is accumulated by the sacoglossan and that shows in vitro cytotoxicity against several cancer cell lines. Our data show that both Bryopsis sp. and Elysia rufescens are chemically protected against fish predators, as indicated by the deterrent properties of their extracts at naturally occurring concentrations. Following bioassay-guided fractionation, we observed that the antipredatory compounds of Bryopsis sp. were present in the butanol and chloroform fractions, both containing the depsipeptide kahalalide F. Antipredatory compounds of Elysia rufescens were exclusively present in the dichloromethane fraction. Further bioassay-guided fractionation led to the isolation of kahalalide F as the only compound responsible for the deterrent properties of the sacoglossan. Our data show that kahalalide F protects both Bryopsis sp. and Elysia rufescens from fish predation. This is the first report of a diet-derived depsipeptide used as a chemical defense in a sacoglossan.  相似文献   
8.
The effects of intracavity reflections in active racetrack semiconductor resonator structures are studied. The incorporation of active material facilitates probing into effects stemming from even minute reflections, such as mode mismatching, which are almost undetectable in passive structures. The spectral response of these structures are studied by the transfer matrix method that models the racetrack resonator as a multicavity structure formed by the various optical paths induced by intracavity reflections. The signature of the structural and operational parameters on the spectral response enables the identification of the conditions for the appearance of interesting spectral properties such as mode splitting and Fano resonances.  相似文献   
9.
Apart from the retinoic acid nuclear receptor family, there are two low molecular weight (15 kD) cellular retinoic acid binding proteins, named CRABPI and II. Mouse monoclonal and rabbit polyclonal antibodies were raised against these proteins by using as antigens either synthetic peptides corresponding to amino acid sequences unique to CRABPI or CRABPII, or purified CRABP proteins expressed in E. coli. Antibodies specific for mouse and/or human CRABPI and CRABPII were obtained and characterized by immunocytochemistry and immunoblotting. They allowed the detection not only of CRABPI but also of CRABPII in both nuclear and cytosolic extracts from transfected COS-1 cells, mouse embryos, and various cell lines.  相似文献   
10.
To investigate the developmental and regional expression of the NR1-subunit of the NMDA-receptor on the protein level, two polyclonal antisera [NR1(N) and NR1(C)] were raised against fusion proteins derived from the N- and C-terminal domain of the NR1-subunit, respectively. In Western blots of rat brain membranes, both antisera specifically recognized a single protein band with an apparent molecular size of 115 kDa. The regional distribution of the NR1-subunit immunoreactivity was analyzed in the developing and adult rat brain using sections blotted onto nitrocellulose membranes for immunostaining. With the NR1(N)-antiserum, strongest signals were detected in hippocampus, followed by cortex, striatum and thalamus, and weaker staining was observed in tectum, brainstem and cerebellum of adult brain. The NR1(C)-immunoreactivity exhibited a similar distribution, except that the staining in thalamus, tectum, brainstem and cerebellum was faint or virtually absent. The distinct pattern of NR1(N)- and NR1(C)-immunoreactivity arose during postnatal development. At birth, moderate staining with both NR1-subunit antisera was observed throughout the brain increasing strongly in most brain regions until postnatal day 21. In some brain areas, however, the NR1(C)-, in contrast to the NR1(N)-staining, decreased postnatally e.g. in thalamus, tectum and brainstem. The restricted staining intensity of the NR1(C)-antiserum in particular areas of adult and developing brain appears to reflect the emergence of C-terminal splice variants of the NR1-subunit which are not recognized by the NR1(C)-antiserum.  相似文献   
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