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101.
102.
We investigate sampling plans in time sequential testing af snrvival distributions, when the study time is fixed. We obtain the asymptotic value of optimal sampling plans as the error probabilities of the test approach zero.  相似文献   
103.
A novel measurement method to extract the spatial distribution of channel hot electron injection is described. The method is based on characterization of localized trapped-charge in the nitride read-only memory (NROM) device. The charge distribution is determined by iteratively fitting simulated subthreshold and gate induced drain leakage (GIDL) currents to measurements. It is shown that the subthreshold and the GIDL measurements are sensitive to charge trapped over the n+ junction edge. Their characteristics are determined by the trapped charge width, density and location and the associated fringing field. Extremely high sensitivity of the GIDL measurement to localized charge over the n+ junction is demonstrated. The extracted charge distribution width is shown to be /spl sim/40 nm, located over the junction edge.  相似文献   
104.
We consider in this paper a continuous-time stochastic hybrid control system with a finite time horizon. The objective is to minimize a linear function of the expected state trajectory. The state evolves according to a linear dynamics. However, the parameters of the state evolution equation may change at discrete times according to a controlled Markov chain which has finite state and action spaces. We use a procedure similar in form to the maximum principle; this determines a control strategy which is asymptotically optimal as the number of transitions during the finite time horizon grows to infinity.  相似文献   
105.
An electrons retention model for localized charge, trapped in ONO stacked dielectric, is introduced utilizing the nitride read-only memory (NROM) device. The observed reduction in threshold voltage (retention loss) of a programmed cell is explained in terms of lateral charge redistribution in the nitride layer. Assuming a thermal emission mechanism, the energy levels of the electrons traps were extracted and found to be distributed continuously in the nitride band gap, with a median value of ~2.12 eV below the conduction band. Utilizing these findings, the model allows a prediction of the retention loss over wide range of temperatures, between 140°C-300°C, long times, up to 10 7 s, large retention loss levels, ~90%, and programming windows, 1.9-3.3 V. Based on this work the ten-year relative retention loss at 140°C of an NROM cell is expected to be 14% (VDS=0.1 V) and the equivalent uncycled product loss is expected to be 8%  相似文献   
106.
A family of user-programmable peripherals, utilizing an integration strategy based on a programmable system device (PSD) concept, is described. Specifically, PSD is an efficient and highly configurable integration of high-density memory and LSI level logic blocks. The configurability is derived by providing programmable logic and programmable interconnect. PSDX is the first PSD family of programmable microcontroller peripherals; it integrates 256 kb to 1 Mb of EPROM, 16 kb of SRAM, a 28-input by 42-product term programmable logic device (PLD), and flexible I/O ports. This family is primarily targeted for embedded microcontroller applications. Using one PSD device it is possible to replace all the core peripherals in the system and, as a result, achieve a reduction in components, power dissipation, and overall system cost. The flexible architecture is achieved by providing 46 configuration options, which allows the PSD to interface with virtually any 8- or 16-b microcontroller. The integration is made possible by developing a special configurability and testability scheme. These parts are realized on a 1.2-μm CMOS EPROM process  相似文献   
107.
108.
This paper presents a new SRAM cell concept which offers cell scaling without requiring complicated, specialized processing technology. The proposed cell utilizes a bipolar transistor in an open-base (base is floating) configuration as a simple means of realizing a high impedance load element. The Bipolar Transistor Load (BTL) is designed such that its open base current (the holding current) is always large enough to compensate for the NMOS pull-down transistor leakage current. The load holding current and the pull-down transistor leakage current are based on the same physical mechanism, namely thermal generation, as a result the load exhibits current tracking properties over varying process and temperature conditions. The cell size is 72 μm2 with typical 0.8 μm design rules, which is about a 60% reduction as compared to a standard 6-T full CMOS cell. The operating properties of the BTL cell were studied analytically and characterized experimentally. The BTL SRAM module can be easily integrated as part of any CMOS process with minimal additional processing steps  相似文献   
109.
Since polyimides are well known for their excellent chemical and thermal stability and outstanding mechanical properties there is increasing interest in developing polyimide-based inks to produce additively manufactured parts with properties superior to those of currently available materials. Usage of bismaleimides (BMI) as precursors allows polyimides to be fabricated via PolyJet™ printing (Stratasys Ltd., Rehovot, Israel). Characterization of the curing kinetics is a central part of process development, as fast curing initiated by UV light is desired. Here, a comprehensive study of thermal and UV curing of BMI oligomers with various molecular weights and chemical structures is presented. Fourier transform infrared spectroscopy serves as a tool for determining the curing degree. Furthermore, an estimation of the activation energy for thermal curing is performed. UV curing of the selected BMIs leads to highly crosslinked, thermoset polymers with excellent chemical resistance and thermal stability which are of great interest for PolyJet™ 3D printing. © 2018 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47244.  相似文献   
110.
    
Aggressive chemotherapy treatment may lead to male infertility. Prepubertal boys do not produce sperm at this age, however, they have spermatogonial stem cells in their testes. Here, we examined the effect of intraperitoneal injection of cyclophosphamide (CP) on the capacity of immature mice (IM) to develop spermatogenesis in vivo and in vitro [using methylcellulose culture system (MCS)]. Our results show a significant decrease in testicular weight, total number of testicular cells, and the number of Sertoli, peritubular, premeiotic, and meiotic/post-meiotic cells, but an increase in the percentages of damaged seminiferous tubules in CP-treated IM compared to control. The functionality of Sertoli cells was significantly affected. The addition of testosterone to isolated cells from seminiferous tubules of CP-treated IM significantly increased the percentages of premeiotic (CD9-positive cells) and meiotic/post-meiotic cells (ACROSIN-positive cells) developed in MCS compared to control. The addition of FSH did not affect developed cells in MCS compared to control, but in combination with testosterone, it significantly decreased the percentages of CD9-positive cells and ACROSIN-positive cells. The addition of IL-1 did not affect developed cells in MCS compared to control, but in combination with testosterone, it significantly increased the percentages of VASA-positive cells and BOULE-positive cells compared to IL-1 or testosterone. Addition of TNF significantly increased only CD9-positive cells in MCS compared to control, but in combination with testosterone, it significantly decreased ACROSIN-positive cells compared to testosterone. Our results show a significant impairment of spermatogenesis in the testes of CP-treated IM, and that spermatogonial cells from these mice proliferate and differentiate to meiotic/post-meiotic cells under in vitro culture conditions.  相似文献   
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