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1.
In this work, a built-in self-testing (BIST) method is proposed to detect nontraditional faults of embedded memory arrays for a system-on-chip (SoC) design. The nontraditional faults include single-cell read-sensitive faults and read coupling faults. The BIST method can efficiently deal with embedded memory arrays spatially distributed on the entire SoC chip. The concept of redundant read-write operations is applied to detect all embedded memory arrays with different sizes simultaneously. The redundant operations do not affect the fault coverage of all nontraditional faults discussed in this paper. The method has the advantages of low hardware overhead, short test time, and high fault coverage for nontraditional memory defects.  相似文献   
2.
Seven monoterpenes in 4 aromatic plants (sage, cardamom, lavender, and rosemary) were quantified in liquid extracts and directly in solid samples by means of dynamic headspace‐gas chromatography‐mass spectrometry (DHS‐GC‐MS) and multiple headspace extraction‐gas chromatography‐mass spectrometry (MHSE), respectively. The monoterpenes were 1st extracted by means of supercritical fluid extraction (SFE) and analyzed by an optimized DHS‐GC‐MS. The optimization of the dynamic extraction step and the desorption/cryo‐focusing step were tackled independently by experimental design assays. The best working conditions were set at 30 °C for the incubation temperature, 5 min of incubation time, and 40 mL of purge volume for the dynamic extraction step of these bioactive molecules. The conditions of the desorption/cryo‐trapping step from the Tenax TA trap were set at follows: the temperature was increased from 30 to 300 °C at 150 °C/min, although the cryo‐trapping was maintained at ?70 °C. In order to estimate the efficiency of the SFE process, the analysis of monoterpenes in the 4 aromatic plants was directly carried out by means of MHSE because it did not require any sample preparation. Good linearity (r> 0.99) and reproducibility (relative standard deviation % <12) was obtained for solid and liquid quantification approaches, in the ranges of 0.5 to 200 ng and 10 to 500 ng/mL, respectively. The developed methods were applied to analyze the concentration of 7 monoterpenes in aromatic plants obtaining concentrations in the range of 2 to 6000 ng/g and 0.25 to 110 μg/mg, respectively.  相似文献   
3.
In this article we propose a multiple-output parity bit signature generation method for exhaustive testing of VLSI circuits. Given a multiple-output combinational circuit, a parity bit signature is generated by first EXORing all the outputs to produce a new output function and then feeding this resulting function to a single-output parity bit signature generator. The method preserves all the desirable properties of the conventional single-output circuits response analyzers and can be readily implemented using the current VLSI technology.  相似文献   
4.
The intracellular transport of drugs and therapeutics represents one of the most exciting and challenging areas at the interface of chemistry, biology, and medicine. Most of the effort in this field so far has been devoted to the development of peptide‐based delivery systems that can translocate therapeutic agents into their intracellular targets. More recently, the use of bioinspired non‐natural foldamers has resulted in the successful delivery of cargo molecules, which possess a wide range of sizes and physicochemical properties across the cell membrane. We report herein the synthesis of aromatic amide foldamers and their biological evaluation as cell‐penetrating agents. By using a well‐established synthetic route, a series of fluorescein‐labeled cationic aryl amide conjugates has been constructed, and their cellular uptake into various human cell lines has been analyzed by flow cytometry and fluorescence microscopy. The assays revealed that longer oligomers achieve greater cellular translocation, with octamer Q8 proving to be a remarkable vehicle for all three cell lines. Biological studies have also indicated that these helices are biocompatible, thus showing promise in their application as cell‐penetrating agents and as vehicles to deliver biologically active molecules into cells.  相似文献   
5.
The design of efficient time compression support hardware for built-in self-testing (BIST) is of great importance in the design and manufacture of VLSI circuits. The test data outputs in BIST are ultimately compressed by time compaction hardware, commonly called a response analyzer, into signatures. Several output response compaction techniques to aid in the synthesis of such support circuits already exist in literature, and parity bit signature coupled with exhaustive testing is already well known to have certain very desirable properties in this context. This paper reports new time compaction techniques utilizing the concept of parity bit signature that facilitates implementing such support circuits using nonexhaustive or compact test sets, with the primary objective of minimizing the storage requirements for the circuit under test (CUT) while maintaining the fault coverage information as best as possible.  相似文献   
6.
In this work, we performed infrared spectroscopic studies of the reaction of poly(acrylic acid) (PAA) and metal oxides (ZnO, CaO, CuO, Cr2O3, and Al2O3). Factors such as the amount of metal oxide, reaction time, solvents, the kind of metal oxides, and temperature were also evaluated to derive the optimum condition for this reaction. The reactions of Cr2O3 and Al2O3 were far from complete. An extra solvent added to the reaction system could increase the solubility of PAA and metal oxide in the solution so as to completely react. The reactivity of the reaction was increased by using the hydrophilic solvent, particularly H2O and CH3OH. Moreover, the reaction rate increased when temperature decreased. The reactivity of the reaction was proportional to the pH value of the metal oxide in the aqueous solution. © 1997 John Wiley & Sons, Inc.  相似文献   
7.
This paper presents a test method for testing two-D-flip-flop synchronizers in an asynchronous first-in-first-out (FIFO) interface. A faulty synchronizer can have different fault behaviors depending on the input application time, the fault location, the fault mechanism, and the applied clock frequency. The proposed test method can apply the input patterns at different time and generate capture clock signals with different frequency regardless of phase-locked loop (PLL) of the design. To implement the proposed test method, channel delay compensator, delayed scan enable signal generator, launch clock generator, and capture clock generator are designed. In addition, a well-designed calibration method is proposed to calibrate all programmable delay elements used in the test circuits. The proposed test method evolves to several test sections to detect all possible faults of the two-D-flip-flop synchronizers in the asynchronous FIFO interface.  相似文献   
8.
In this paper, a systematic methodology for the dynamic analysis of tendon‐driven robotic mechanisms is presented. The approach utilizes the recursive Newton‐Euler equations to compute the kinematic and dynamic equations of all links that locate on the transmission line of a tendon‐driven robotic mechanism. The inertias of the intermediate links in the mechanism are taken into account. It is shown that the dynamic equations can be established in a recursive manner from the end‐effector links toward the proximal links and can be solved at the proximal end without the need of solving the simultaneous system equations. The joint reaction forces and the tension in each segment of tendon can be also obtained. The methodology can be applied to both endless and open‐ended tendon drives. © 2003 Wiley Periodicals, Inc.  相似文献   
9.
In this paper, a new force transmission index called the mean force transmission index (MFTI) is proposed, and the force transmissibility analysis procedure is established for parallel manipulators. The MFTI is an extended definition of the force transmission index (FTI) introduced by the authors previously. It is shown that the FTI is a function of the input velocity ratio (IVR) for a multi‐DOF mechanism of the same configuration. To represent the force transmissibility by a definite value, the MFTI is defined as the mean value of the normalized FTIs function over the whole range of the IVR. The force transmissibility analysis of two planar parallel manipulators is illustrated using the MFTI method. The result is compared with that of the Jacobian matrix method and the joint force index (JFI) method. It shows that, especially for symmetric parallel manipulators, an approximate inverse‐proportionality relationship exists between the JFI and MFTI, and between the maximum input torque/force and MFTI. It is concluded that the MFTI can be used as a quantitative measure of the force transmissibility performance for parallel manipulators. In the end, a design optimization problem is studied by taking the global force transmission index as the objective function. © 2003 Wiley Periodicals, Inc.  相似文献   
10.
Investigated the attitudinal impacts of receiving formal performance appraisal feedback. Based on the suggestion that the feedback that one is "satisfactory" will be disconfirming for many feedback recipients, it was hypothesized that attitudes toward the performance appraisal systems and organizational commitment will decrease and remain lower for those receiving satisfactory ratings, whereas the attitudes of those receiving higher appraisal ratings will remain unchanged. The hypotheses were tested on panels of management and nonmanagement employees (the latter receiving new appraisals 12 mo after their managers) in 2 federal agencies over a 30-mo period using perceived and actual performance ratings. There was a significant and stable drop in the organizational commitment of satisfactory employees after the introduction of formal appraisals, with mixed results for attitudes toward the appraisal system. Findings suggest that potentially negative consequences of implicitly comparative formal performance appraisals can occur for those performing at a satisfactory, but not outstanding, level. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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