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81.
Liu D Cao Y Kim KH Stanek S Doungratanaex-Chai B Lin K Tavanapong W Wong J Oh J de Groen PC 《Computer methods and programs in biomedicine》2007,88(2):152-163
Colonoscopy is an endoscopic technique that allows physicians to inspect the inside of the human colon. During a colonoscopic procedure, a tiny video camera at the tip of the endoscope generates a video signal of the internal mucosa of the colon. In current practice, the entire colonoscopic procedure is not routinely captured. Software tools providing easy access to important contents of videos that are digitally captured during colonoscopy are not available. Hence, it is very time consuming to review an entire video, locate important contents, annotate them, and extract the annotated contents for research, teaching, and training purposes. Arthemis, a software application, was developed to facilitate this process. For convenient data sharing, Arthemis allows annotation according to the European Gastrointestinal Society for Endoscopy (ESGE) Minimal Standard Terminology (MST), an internationally accepted standard for digestive endoscopy. Arthemis is part of our integrated capturing and content analysis system for colonoscopy called Endoscopic Multimedia Information System (EMIS). This paper presents Arthemis as a component of EMIS, the design and implementation of Arthemis, and key lessons learned from the development process. 相似文献
82.
Abstracct In the silicon fusion bonding (SFB) process, the influence of post-annealing atmospheres on the micro-gap existing at the Si-Si bonding interface was investigated with the observation of ultrasonic images, angle lap-stained junctions and cross section SEM morphologies. Additionally, the bonding strength and the electrical properties of diodes were compared after annealing processes at 100/dg fo 10 s to 10 h in wet O2, dry O2 and N2 atmospheres. Our results show that a significant saving of annealing time necessary to eliminate the non-contact micro-gap region having a width of 0.1 m can be obtained if the hydrogenbonded wafer pair is pre-stabilized and post-annealed in wet O2 (95°C water bubbling) rather than in a dry O2 or N2 atmosphere. Based on the above result, we propose that the stabilizing and annealing step in highlt oxidizing atmosphere has an important role in the oxide filling-up phenomenon between wafer and wafer gap, in addition to the well-known mechanism of wafer plastic deformation at high temperature followed by solid-state diffusion of Si and O atoms. 相似文献
83.
The Semantic Web and ontologies have received increased attention in recent years. The delivery of well-designed ontologies enhances the effect of Semantic Web services, but building ontologies from scratch requires considerable time and effort. Modularizing ontologies and integrating ontology modules to a given context help users effectively develop ontologies and revitalize ontology dissemination. Therefore, various tools for modularizing ontologies have been developed. However, selecting an appropriate tool to fit a given context is difficult because the assumptions for the approaches greatly vary. Therefore, a suitable framework is required to compare and help screen the most suitable modularization tool.In this research, we propose a new evaluation framework for selecting an appropriate ontology modularization tool. We present three aspects of tool evaluation as the main dimensions for the assessment of modularization tools: tool performance, data performance, and usability.This study provides an implicit evaluation and an empirical analysis of three modularization tools. It also provides an evaluation method for ontology modularization, enabling ontology engineers to compare different modularization tools and easily choose an appropriate one for the production of qualifying ontology modules.The experimental results indicate that the proposed evaluation criteria for ontology modularization tools are valid and effective. This research provides a useful method for assessing and selecting ontology modularization tools. Modularization performance, data performance, and usability are the three modularization aspects designed and applied to the context of ontology. We provide a new focus on the comprehensive framework to evaluate the performance and usability of ontology modularization tools. The proposed framework should be of value to both ontology engineers, who are interested in ontology modularization, and to practitioners, who need information on how to evaluate and select a specific type of ontology tool in accordance with the requirements of the individual environment. 相似文献
84.
Computer-aided automatic analysis of microscopic leukocyte is a powerful diagnostic tool in biomedical fields which could reduce the effects of human error, improve the diagnosis accuracy, save manpower and time. However, it is a challenging to segment entire leukocyte populations due to the changing features extracted in the leukocyte image, and this task remains an unsolved issue in blood cell image segmentation. This paper presents an efficient strategy to construct a segmentation model for any leukocyte image using simulated visual attention via learning by on-line sampling. In the sampling stage, two types of visual attention, “bottom-up” and “top-down” together with the movement of the human eye are simulated. We focus on a few regions of interesting and sample high gradient pixels to group training sets. While in the learning stage, the SVM (support vector machine) model is trained in real-time to simulate the visual neuronal system and then classifies pixels and extracts leukocytes from the image. Experimental results show that the proposed method has better performance compared to the marker controlled watershed algorithms with manual intervention and thresholding-based methods. 相似文献
85.
Yun-Jae Kim Chang-Kyun Oh Man-Sik Myung Jin-Moo Park 《Engineering Fracture Mechanics》2006,73(13):1849-1864
In the present work, fully plastic analyses for notched bars and (plane strain) plates in tension are performed, via finite element (FE) limit analysis based on non-hardening plasticity, from which plastic limit loads and stress fields are determined. Relevant geometric parameters are systematically varied to cover all possible ranges of the notch depth and radius. For the limit loads, it is found that the FE solutions for the notched plate agree well with the existing solution. For the notched bar, however, the FE solutions are found to be significantly different from known solutions, and accordingly the new approximation is given. Regarding fully plastic stress fields, it is found that, for the notched plate, the maximum hydrostatic (mean normal) stress overall occurs in the center of the specimen, which strongly depends on the relative notch depth and the notch radius-to-depth ratio. On the other hand, for the notched bar, the maximum hydrostatic stress can occur in between the center of the specimen and the notch tip. The maximum hydrostatic stress for a given notch depth can occur not for the cracked case, but for the notched case with a certain radius. This is true for both bars and plates. For a given notch radius, on the other hand, the maximum hydrostatic stress increases monotonically with the decreasing notch radius. 相似文献
86.
Seogil Oh Jungwoo Moon Taewook Kang Surin Hong Jongheop Yi 《Journal of Electroceramics》2006,17(2-4):999-1003
The use of surface plasmon resonance (SPR) spectroscopy has been applied to a wide variety of fields such as biosensors and
surface analysis instruments. In general, a SPR substrate is prepared using self-assembled monolayer (SAM) method of organic
molecules as receptor for the target on a layer of gold or silver. However, mesoporous inorganic materials such as SBA-15
have benefits as sensor substrate for SPR. Mesoporous silica has a large surface area which receptor molecule can be attached
and has a rigid body which has an excellent stability in the extreme condition compared to organic sensing layer. We prepared
an organic modified mesoporous silica and successfully immobilized it on a gold surface, in an attempt to use as a substrate
for SPR spectroscopy. For the comparison of sensitivity of prepared substrate, Pt2+ detection was selected as a model system. Substrate prepared in this study exhibited the capability of selective sensing
for Pt2+ ions. 相似文献
87.
Hoon Kim Sung Kee Kim Hanlim Lee Seongtaek Hwang Yunje Oh 《Photonics Technology Letters, IEEE》2006,18(8):947-949
We propose and demonstrate a way to improve the dispersion-limited reach of electroabsorption modulated lasers (EMLs). We generate continuous-phase frequency-shift keying/amplitude-shift keying (ASK) signals with the EML by applying a small current modulation to the laser diode (LD) on top of electroabsorption-modulated ASK signals. The amount of frequency deviation induced by the current modulation is adjusted to have the EML output signals experience /spl pi/ phase shift at every space. The experimental demonstration shows that with the proposed scheme we can increase the dispersion-limited transmission distance of the EML-based transmitter by 25%-75%, and it can be further improved by employing an LD with flat frequency-modulation response. 相似文献
88.
N.S. Ergang J.C. Lytle K.T. Lee S.M. Oh W.H. Smyrl A. Stein 《Advanced materials (Deerfield Beach, Fla.)》2006,18(13)
The inside cover shows an SEM image of a 3D‐interpenetrating electrochemical cell with submicrometer features, as reported by Stein and coworkers on p. 1750. The pores of an inverse‐opal carbon electrode are coated with a conformal layer of a polymer separator and infiltrated with vanadia to form the opposite electrode after lithiation. The idealized scheme illustrates lithium‐ion transport between the electrodes through the polymer membrane. 相似文献
89.
Dong-Woo Suh Chang-Seok Oh Sung-Joon Kim 《Metallurgical and Materials Transactions A》2005,36(4):1057-1059
High-angle grain-boundary spacing in deformed austenite is analyzed using Ni-30Fe alloy to explain the change of ferrite grain
size by severe plastic deformation (SPD) of austenite in low carbon steel. It is suggested that constant high-angle grain-boundary
spacing in deformed austenite resulting from dynamic recrystallization (DRX) or geometric DRX is responsible for the limit
of ferrite grain refinement over a certain level of plastic deformation of austenite. 相似文献
90.
Recrystallization and grain growth of a cold-rolled gold sheet with 98 pct reduction in area (RA) were investigated with electron
backscatter diffraction (EBSD) and X-ray diffraction (XRD). Gold with some dopants (Be, Ca, and La) was used in this research
and its recrystallization temperature was 320 °C. Isothermal annealing experiments at 400 °C, 500 °C, and 600 °C were carried
out for the cold-rolled gold sheet, and recrystallization texture was examined. In the cold-rolled gold sheet, α- and β-fibers were measured mainly and some shear texture components were found on the surface. Shear texture components remained
on the surface for 2 hours at 400 °C and were consumed by other recrystallized grains after 24 hours at 400 °C. Microstructure
and texture evolution during in-situ annealing at 400 °C were investigated from the cold-rolled state to the fully recrystallized state using EBSD. Most of the
newly, recrystallized grains came from the deformed β-fiber regions and consisted of β-fiber, cube, and other random orientations. 相似文献