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131.
Magnetization reversal processes in microstructured NiFe rings are studied by fringe-field-induced local Hall magnetometry.
This semiconductor-based technique yields a high sensitivity of magnetic stray fields and allows us to detect magnetization
hysteresis loops of single NiFe rings. The transition fields can be controlled by the ratio between inner- and outer-ring
diameter. Comparison between Hall measurements and numerical simulation suggests that there are four different magnetization
states in two integrated rings.
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132.
T Yambe S Nanka S Kobayashi A Tanaka M Yoshizawa K Abe K Tabayashi H Takeda S Nitta 《Canadian Metallurgical Quarterly》1998,44(5):M700-M703
To develop the optimal automatic control algorithm for an in vivo artificial heart system, investigation of the basic characteristics of the cardiovascular system may be important. The clinical significance of chaotic dynamics in the cardiovascular system has attracted attention. The circulation is a so-called complex system with many feedback circuits, making it very difficult to investigate the origin of chaos within the system. In this study, we investigated the origin of chaos by open loop analysis with an artificial heart (which has no fluctuation in pumping rate or contraction power) in chronic animal experiments with healthy adult goats. As a result, in the artificial heart circulatory time series data, low dimensional deterministic chaos was discovered by nonlinear mathematical analysis, suggesting the importance of blood vessels in the chaotic dynamics of the cardiovascular system. To investigate the origin of chaos further, sympathetic activity was directly measured in animals with artificial hearts. Chaotic dynamics was also recognized in sympathetic action potentials, even during artificial heart circulation. Coupling of the nonlinear information between blood vessels and sympathetic activity was suggested by analysis of mutual information. In chaotic dynamics, the central nervous system (CNS) played an important role through sympathetic activity. These findings may be useful for the development of an automatic control algorithm for an artificial heart. 相似文献
133.
Katsumi Nitta Yoshihisa Ohtake Shigeru Maeda Masayuki Ono Hiroshi Ohsaki Kiyokazu Sakane 《New Generation Computing》1993,11(3-4):423-448
This paper presents HELIC-II, a legal reasoning system on the parallel inference machine. HELIC-II draws legal conclusions for a given case by referring to a statutory law (legal rules) and judicial precedents (old cases). This system consists of two inference engines. The rule-based engine draws legal consequences logically by using legal rules. The case-based engine generates legal concepts by referencing similar old cases. These engines complementally draw all possible conclusions, and output them in the form of inference trees. Users can use these trees as material to construct arguments in a legal suit. HELIC-II is implemented on the parallel inference machine, and it can draw conclusions quickly by parallel inference. As an example, a legal inference system for the Penal Code is introduced, and the effectiveness of the legal reasoning and parallel inference model is shown. 相似文献
134.
Superconducting generators have many advantages, one of which is their ability to improve the stability of power systems because of their low synchronous impedances. The advantage may be increased by adoption of high-response excitation. The first 100 kVA high-response excitation superconducting generator has now been built. One of the problems in the design of such generators involves the characteristics of the field circuit, i.e., the field armature winding, losses in the component materials, and loss in the superconducting field winding. In this paper, a 2-dimensional electromagnetic field analysis of field circuit characteristics is presented. 相似文献
135.
136.
Surface physical properties and chemical states on a nanometer scale were investigated to provide a direct insight into the
mechanism of near-frictionless performance displayed by diamond-like carbon (DLC) coatings in engine oil lubricants. A mechanism
was revealed by combining nanoprobe methods with surface chemical analysis. The near-frictionless behavior observed in the
lubricants was found to stem from strong repulsive force between hydrogen-terminated carbon chains, originating from the bonding
of oil additive molecules on the DLC coating surface producing sliding contact between H-terminated alkyl chain layers. 相似文献
137.
Modeling legal argumentation is one of the most important research in AI and Law, and a lot of models have been proposed. However, most research has not treated value judgement and debate. In this paper, we introduce a legal reasoning model which covers various aspects of legalreasoning such as making argument, selecting argument and debate.Furthermore, we present how criminal law is described and reasoned inthis model. 相似文献
138.
Ohta J. Nitta Y. Tai S. Takahashi M. Kyuma K. 《Lightwave Technology, Journal of》1991,9(12):1747-1754
A novel type of photodetector called a variable sensitivity photodetector (VSPD) has been developed for an optical implementation of a neural network. The function of the VSPD is a photodetector with functions of both a spatial light modulator and a photodetector. The VSPD with a metal-semiconductor-metal structure is shown to be suitable for the implementation of the analog synaptic weight with a bipolar value. A two-dimensional 8×8 array of VSPDs was fabricated on a GaAs substrate and integrated with a light-emitting-diode array with eight lines in hybrid form. This chip can simulate an eight-neuron system with 64 variable synaptic connections. The application to pattern classification was demonstrated by using the chip. The chip was used to classify 12 patterns into three categories by the backpropagation learning algorithm in a three-layered network. The authors studied how the nonlinear and nonuniform characteristics of the VSPD array device affect the learning performance 相似文献
139.
Atsumi Nitta Hideyuki Nakamura Takayuki Komatsu Kazumasa Matusita 《Journal of Materials Science》1990,25(6):2857-2860
The interface reactions between SiO2-PbO melt and Ni-Zn ferrite were studied using electron probe microanalysis and X-ray diffraction. The mechanisms of interface reaction were investigated in relation to the glass-forming region. No intermediate layers were produced at the interface between SiO2-PbO glass and Ni-Zn ferrite because of the small amount of dissolution of Ni2+ ion from the ferrite. A model of the interface reaction mechanism between SiO2-PbO melt and Ni-Zn ferrite is proposed. 相似文献
140.
A method for the isolation of the DNA fragments containing structural genes at the beginning, in the middle and at the end of the coding strand is described. It involves mechanical or enzymatic shearing, exonuclease treatment, hybridization with mRNA and subsequent retention of DNA-mRNA complex on poly(U)-Sepharose. Hybridization of the DNA fragments with mRNA takes place with high specificity and isolated material is enriched in structural genes. Applications of this method for gene isolation are discussed. 相似文献