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81.
Kwan Christine M. L.; Chun Kevin M.; Chesla Catherine A. 《Canadian Metallurgical Quarterly》2011,2(2):115
Practical knowledge on how to tailor research methods for Asian Americans is relatively scarce despite the rapid population growth of this ethnic group and the ongoing calls for greater cultural competence among researchers. Based on a 4-year qualitative study of family and cultural issues in diabetes management among Chinese American immigrants, this article presents data-based analyses of culturally nuanced group interview processes, and recommendations for conducting culturally appropriate group interviews. Group interview processes were prominently shaped by four cultural norms: sensitivity to social hierarchy, monitoring public display of strong emotions, face concerns, and emphasis on group harmony. Strategies for facilitating open and dynamic group interviews in the presence of these norms were identified. Skillful facilitation of group processes, either by accommodating or diffusing norms, was required to promote participant rapport and encourage disclosure of everyday experience. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
82.
Chin-Tau Lea Chi-Ying Tsui Bo Li Kwan C.-Y. Chan S.K.-M. Chan A.H.-W. 《IEEE network》1999,13(1):48-55
Future networks need both connectionless and connection-oriented services. IP and ATM are major examples of the two types. Connectionless IP is more efficient for browsing, e-mail, and other non-real-time services; but for services demanding quality and real-time delivery, connection-oriented ATM is a much better candidate. Given the popularity of the Internet and the established status of ATM as the broadband transport standard, it is unlikely that one can replace the other. Therefore, the challenge we face lies in finding an efficient way to integrate the two. This article describes a research project reflecting this trend. The project aims at efficient integration of the two to eliminate the deficiencies of a standalone ATM or IP network 相似文献
83.
Load-Balanced Optical Switch (LBOS) [20] ensures close-to-100% throughout and all-optical transmission between linecards. In this paper, we extend LBOS for multi-cabinet implementation. The challenges lie in the fact that the practical implementation requirements in single-cabinet LBOS become un-scalable for multi-cabinet scenario. First of all, we remove the restriction on LBOS that propagation delay (tp) between adjacent linecards must equal to the transmission time (tpkt) for sending one packet. The delay tp is relaxed to be any value, which can accommodate the long and unequal distances fibers among cabinets. Secondly, we outstrip the upper bound of switch size N = 160 in LBOS. The basic idea is that the adjacent linecards share an identical channel/wavelength. Then LBOS can be scaled to support the large switch size of multi-cabinet. Last but not least, a more feasible fair scheduler is devised to replace the original one in LBOS. The simulation results show that multi-cabinet LBOS yields a much better delay/throughput performance than other multi-cabinet optical switches (e.g. Fasnet [8]). 相似文献
84.
It is important to determine the residence time distribution (RTD) of a mill in order to predict the performance of the mill. In this study, the residence time distribution of a continuous centrifugal mill was measured experimentally by using aluminum powder as a tracer in a dry-grinding environment. Aluminum powder was placed into the continuous centrifugal mill chamber as a pulse under a steady-state condition, and then, the discharge time and proportional concentration of the tracer was measured using a metal detector at various G/D ratios and feed rates. During the measurement procedure, the mill product was collected and analyzed with regard to the size distribution to investigate the relationship between the mill product and the characteristics of RTD. In addition, the mill hold-up data was also analyzed after measurement. These test results can be used to predict the mill product size distribution in combination with a kinetic grinding model. 相似文献
85.
Han Kyun Choi Hyun Soo Kim Kwan Heng Lee 《The International Journal of Advanced Manufacturing Technology》2010,50(1-4):235-252
The use of highly detailed models is continuously increasing in computer-aided design (CAD) design and computer graphics field as the technology of range scanners advances. Real-time rendering and manipulating applications are also increasing to support applications in various areas such as collaborative design and scientific visualization. Although graphics hardware technology has been improved rapidly, more attributes such as color, material property, texture coordinate, and curvature are added to CAD models, and it becomes a challenge to handle and render such heavy models. Consequently, the models with complex mesh need to be approximated to improve the efficiency of rendering and manipulation and to reduce computation time. A considerable amount of work has been done regarding geometry preservation, but relatively little research has been performed to preserve both geometry and additional attributes. We present a feature sensitive simplification method using curvature color as an additional attribute. We also use curvature color filtering and optimal positioning methods after edge collapse to preserve feature more sensitively. Our method is applied to several models, and the performance is demonstrated by comparing it with other methods. 相似文献
86.
韩国建筑师Moon Hoon为大家所认识大概是因为他2005年获得韩国设计大奖的SangSang博物馆,从那座极富工业感和机械感的建筑设计中,我们不难感受到设计师不一样的设计理念与艺术感知。与其说他是一名建筑师,不如说是一个艺术家更为准确。 相似文献
87.
Rong Shean Lee Chin Tarn Kwan 《International Journal of Machine Tools and Manufacture》1997,37(8):1053-1067
In this study, two kinematically admissible velocity fields are derived for the proposed three-dimensional convex circular parallelepiped and convex spherical UBET elements. Those elements are applied to three-dimensional closed-die forging having convex curve surfaces; the capability of the proposed elements is then demonstrated. From the derived velocity fields, the upper-bound loads on the upper die and the velocity field are determined by minimizing the total energy consumption with respect to some chosen parameters. Also, experiments of two closed-die forgings are performed with commercial pure lead billets at the ambient temperature. The theoretical predictions of the forming load correlated well with the experimental results. The results in this study confirm that the elements proposed in this work can effectively be used to predict the forming load accurately in three-dimensional closed-die forging with convex curve surfaces. 相似文献
88.
Kwan C. Schmera G. Smulko J.M. Kish L.B. Heszler P. Granqvist C.-G. 《IEEE sensors journal》2008,8(6):706-713
Conventional agent sensing methods normally use the steady state sensor values for agent classification. Many sensing elements (Hines , 1999; Ryan, 2004; Young, 2003;Qian, 2004; Qian, 2006; Carmel, 2003) are needed in order to correctly classify multiple agents in mixtures. Fluctuation-enhanced sensing (FES) looks beyond the steady-state values and extracts agent information from spectra and bispectra. As a result, it is possible to use a single sensor to perform multiple agent classification. This paper summarizes the application of some advanced algorithms that can classify and estimate concentrations of different chemical agents. Our tool involves two steps. First, spectral and bispectral features will be extracted from the sensor signals. The features contain unique agent characteristics. Second, the features are fed into a hyperspectral signal processing algorithm for agent classification and concentration estimation. The basic idea here is to use the spectral/bispectral shape information to perform agent classification. Extensive simulations have been performed by using simulated nanosensor data, as well as actual experimental data using commercial sensor (Taguchi). It was observed that our algorithms are able to accurately classify different agents, and also can estimate the concentration of the agents. Bispectra contain more information than spectra at the expense of high-computational costs. Specific nanostructured sensor model data yielded excellent performance because the agent responses are additive with this type of sensor. Moreover, for measured conventional sensor outputs, our algorithms also showed reasonable performance in terms of agent classification. 相似文献
89.
Su Kwan Oh Ji-Myon Lee Ki Soo Kim Chul-Wook Lee Hyunsung Ko Sahnggi Park Moon-Ho Park 《Photonics Technology Letters, IEEE》2003,15(12):1680-1682
Planar buried heterostructure (PBH) was adopted to fabricate a sampled grating distributed Bragg reflector laser diode (SGDBR-LD) having a low threshold current and a stable fundamental transverse mode. The etching process for butt-coupling was optimized to improve the reproducibility and the uniformity of the butt-coupled waveguide. The maximum output power of the fabricated SGDBR-LD was 20 mW at 200-mA continuous-wave operation at 25/spl deg/C. The output power was measured 10 and 9 mW higher than those of ridged waveguide (RWG) structure and buried ridge stripe (BRS), and the threshold current was slightly higher than those of RWG and BRS. The spectra of 25 channels spaced 50 GHz within the tuning range of 44.4 nm was obtained by a precise control of SG and phase control currents. The side-mode suppression ratio of more than 35 dB was obtained in the whole tuning range. The output power variation was less than 5 dB, which is 4 dB smaller than that of RWG structure. 相似文献
90.
Spontaneous Ni2+ entry (leak), measured as fluorescence quench in fura-2-loaded HL-60 cells at the excitation wavelength of 360 nm, was strongly inhibited by tetrandrine (TET, 100 microM), a Ca2+ antagonist of Chinese herbal origin. Exposure of the cells for 5 min to saponins from Quillaja saponaria (QS, 30 microg/ml), surfactants well known to permeabilize the plasma membrane by complexing with cholesterol, promoted Ni2+ entry without causing fura-2 leak-out. Unexpectedly, TET caused an immediate (within 2.5 min) augmentation of QS-promoted Ni2+ entry; and a 5-min treatment with both TET and QS resulted not only in an enhanced Ni2+ entry, but also a fura-2 leak-out. Ginseng saponins (100 microg/ml) alone or together with TET did not cause such a permeabilization. Permeabilization induced by 1-3 microM digitonin, another cholesterol-complexing glycoside, could not be enhanced by TET. TET did not affect permeabilization induced by Triton X-100 (0.01%), a detergent which non-specifically disrupts the hydrophobic interaction at the plasma membrane. TET also did not enhance Ni2+ entry triggered by ionomycin (0.35 microM) or SK&F 96365 (20 microM). Further, it did not augment Ni2+ entry when the plasma membrane fluidity was modulated by changes of temperature (27-47 degrees C) or treatment with 5% ethanol. This QS-promoted Ni2+ entry could not be amplified by other lipophilic Ca2+ antagonists, such as diltiazem (100 microM) and verapamil (100 microM). The results hence indicate that TET enhanced Ni2+ entry (or permeabilization) elicited by QS treatment, but not other perturbations of the plasma membrane. We suggest that pore formation at the plasma membrane, a consequence of QS-cholesterol interaction, can be specifically enhanced by TET. Also, a comparative study of the effects of TET and its very close analogues, hernandezine and berbamine, reveals that the methoxyl group at the R2 position of TET appears to be crucial in enhancing QS-promoted Ni2+ entry. 相似文献