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51.
This paper describes the design and fabrication of a MEMS guide plate, which was used for a vertical probe card to test a
wafer level packaged die wafer. The size of the fabricated MEMS guide plate was 10.6 × 10.6 cm. The MEMS guide plate consisted
of 8,192 holes to insert pogo pins, and four holes for bolting between the guide plate and the housing. To insert pogo pins
easily, an inclined plane was defined at the back of each hole. Pitch and diameter of the hole were 650 and 260 μm, respectively.
In order to define inserting holes and inclined planes at an exact position, silicon MEMS technology was used such as anisotropic
etching, deep reactive etching and more. Silicon was used as the material of the guide plate to reduce alignment mismatch
between the pogo pins and solder bumps during a high temperature testing. A combined probe card with the fabricated MEMS guide
plate showed good x–y alignment and planarity errors within ±9 and ±10 μm at room temperature, respectively. In addition, x–y alignment and planarity are ±20 and ±16 μm at 125°C, respectively. The proposed MEMS guide plate can be applied to a vertical
probe card for burn-in testing of a wafer level packaged die wafer because the thermal expansion coefficient of the MEMS guide
plate and die wafer is same. 相似文献
52.
The rise of online social media has led to an explosion of metadata-containing user generated content. The tracking of metadata distribution is essential to understand social media. This paper presents two statistical models that detect interpretable topics over time along with their hashtags distribution. A topic is represented by a cluster of words that frequently occur together, and a context is represented by a cluster of hashtags, i.e., the hashtag distribution. The models combine a context with a related topic by jointly modeling words with hashtags and time. Experiments with real-world datasets demonstrate that the proposed models discover topics over time with related contexts effectively. 相似文献
53.
54.
Codevelopmental learning between human and humanoid robot using a dynamic neural-network model. 总被引:1,自引:0,他引:1
Jun Tani Ryu Nishimoto Jun Namikawa Masato Ito 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2008,38(1):43-59
This paper examines characteristics of interactive learning between human tutors and a robot having a dynamic neural-network model, which is inspired by human parietal cortex functions. A humanoid robot, with a recurrent neural network that has a hierarchical structure, learns to manipulate objects. Robots learn tasks in repeated self-trials with the assistance of human interaction, which provides physical guidance until the tasks are mastered and learning is consolidated within the neural networks. Experimental results and the analyses showed the following: 1) codevelopmental shaping of task behaviors stems from interactions between the robot and a tutor; 2) dynamic structures for articulating and sequencing of behavior primitives are self-organized in the hierarchically organized network; and 3) such structures can afford both generalization and context dependency in generating skilled behaviors. 相似文献
55.
Kim D Cho CH Cho Y Ryu J Bhak J Kim DS 《Journal of molecular graphics & modelling》2008,26(7):1104-1112
Proteins consist of atoms. Given a protein, the automatic recognition of depressed regions, called pockets, on the surface of proteins is important for protein-ligand docking and facilitates fast development of new drugs. Recently, computational approaches have emerged for recognizing pockets from the geometrical point of view. Presented in this paper is a geometric method for the pocket recognition which is based on the Voronoi diagram for atoms. Given a Voronoi diagram, the proposed algorithm transforms the atomic structure to meshes which contain the information of the proximity among atoms, and then recognizes depressions on the surface of a protein using the meshes. 相似文献
56.
Lina Peng K. Selçuk Candan Christopher Mayer Karamvir S. Chatha Kyung Dong Ryu 《Multimedia Tools and Applications》2007,33(3):245-272
In this paper, we present the ARIA media processing workflow architecture that processes, filters, and fuses sensory inputs
and actuates responses in real-time. The components of the architecture are programmable and adaptable; i.e. the delay, size,
and quality/precision characteristics of the individual operators can be controlled via a number of parameters. Each data
object processed by qStream components is subject to transformations based on the parameter values. For instance, the quality of an output data object
and the corresponding processing delay and resource usage depend on the values assigned to parameters of the operators in
the object flow path. In Candan, Peng, Ryu, Chatha, Mayer (Efficient stream routing in quality- and resource-adaptive flow
architectures. In: Workshop on multimedia information systems, 2004), we introduced a class of flow optimization problems that promote creation and delivery of small delay or small resource-usage objects to the actuators in single-sensor, single-actuator
workflows. In this paper, we extend our attention to multi-sensor media processing workflow scenarios. The algorithms we present
take into account the implicit dependencies between various system parameters, such as resource consumption and object sizes.
We experimentally show the effectiveness and efficiency of the algorithms.
相似文献
Kyung Dong RyuEmail: |
57.
Cho EH Kim MR Kim HJ Lee DY Kim PK Choi KM Ryu OH Kim CW 《Proteomics. Clinical applications》2007,1(4):352-361
Diabetic nephropathy (DN) is a serious kidney complication of diabetes, and constitutes the leading cause of end-stage renal disease. The earliest clinical evidence of DN is microalbuminuria, a term which refers to the appearance of small but abnormal amounts of albumin in the urine. However, screening methods for DN, such as biomarker assays, are yet to be developed for type 2 DN. In the present study, in an attempt to identify the biomarkers for initial diagnoses of type 2 DN, the protein profiles of human sera collected from 30 microalbuminuric type 2 diabetic patients were compared with those collected from 30 normoalbuminuric type 2 diabetic patients, via 2-DE. As a result, a total of 18 spots were determined to have different protein levels in the microalbuminuric patients. Twelve spots had lower protein levels of approximately 50%, and the other six had higher levels of approximately 100-300% as compared to the spots of normoalbuminuric patients. These spots were identified with ESI-Q-TOF (ESI-quadrupole-TOF) MS. Among the identified proteins, vitamin D-binding protein (DBP) and pigment epithelium-derived factor (PEDF) were verified by Western blotting. The results of this study indicate that the DBP may be employed as diagnostic and monitoring biomarkers of type 2 DN, contingent on further study into the matter. 相似文献
58.
Parameter-free geometric document layout analysis 总被引:1,自引:0,他引:1
Seong-Whan Lee Dae-Seok Ryu 《IEEE transactions on pattern analysis and machine intelligence》2001,23(11):1240-1256
Automatic transformation of paper documents into electronic documents requires geometric document layout analysis at the first stage. However, variations in character font sizes, text line spacing, and document layout structures have made it difficult to design a general-purpose document layout analysis algorithm for many years. The use of some parameters has therefore been unavoidable in previous methods. The authors propose a parameter-free method for segmenting the document images into maximal homogeneous regions and identifying them as texts, images, tables, and ruling lines. A pyramidal quadtree structure is constructed for multiscale analysis and a periodicity measure is suggested to find a periodical attribute of text regions for page segmentation. To obtain robust page segmentation results, a confirmation procedure using texture analysis is applied to only ambiguous regions. Based on the proposed periodicity measure, multiscale analysis, and confirmation procedure, we could develop a robust method for geometric document layout analysis independent of character font sizes, text line spacing, and document layout structures. The proposed method was experimented with the document database from the University of Washington and the MediaTeam Document Database. The results of these tests have shown that the proposed method provides more accurate results than previous ones 相似文献
59.
This letter presents a new algorithm for blind dereverberation and echo cancellation based on independent component analysis (ICA) for actual acoustic signals. We focus on frequency domain ICA (FD-ICA) because its computational cost and speed of learning convergence are sufficiently reasonable for practical applications such as hands-free speech recognition. In applying conventional FD-ICA as a preprocessing of automatic speech recognition in noisy environments, one of the most critical problems is how to cope with reverberations. To extract a clean signal from the reverberant observation, we model the separation process in the short-time Fourier transform domain and apply the multiple input/output inverse-filtering theorem (MINT) to the FD-ICA separation model. A naive implementation of this method is computationally expensive, because its time complexity is the second order of reverberation time. Therefore, the main issue in dereverberation is to reduce the high computational cost of ICA. In this letter, we reduce the computational complexity to the linear order of the reverberation time by using two techniques: (1) a separation model based on the independence of delayed observed signals with MINT and (2) spatial sphering for preprocessing. Experiments show that the computational cost grows in proportion to the linear order of the reverberation time and that our method improves the word correctness of automatic speech recognition by 10 to 20 points in a RT??= 670 ms reverberant environment. 相似文献
60.
The IEEE 802.16e standard enhances the IEEE 802.16 for the mobility support. Mobile stations can move while receiving services,
thus ongoing IP sessions may be maintained during a handover in the IEEE 802.16e. To reduce handover latency, the idea of
cross-layer handover which incorporates layer 2 handover with IP layer has been devised. Various cross-layer handover schemes
supporting fast handover in the IEEE 802.16e networks have been proposed. However, the problem of the conventional cross-layer
fast handover schemes is that they are heavily influenced by the new address confirmation latency which is the most time-consuming
procedure. In this paper, we propose an enhanced cross-layer fast handover scheme which is not susceptible to the new address
confirmation latency. Detailed performance analysis is performed in terms of the signaling costs and the handover latencies
to show the effectiveness of the proposed scheme compared with the conventional ones. The results of the performance evaluation
confirm the effectiveness of the proposed scheme. 相似文献