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1.
Variation in illumination conditions caused by weather, time of day, etc., makes the task difficult when building video surveillance systems of real world scenes. Especially, cast shadows produce troublesome effects, typically for object tracking from a fixed viewpoint, since it yields appearance variations of objects depending on whether they are inside or outside the shadow. In this paper, we handle such appearance variations by removing shadows in the image sequence. This can be considered as a preprocessing stage which leads to robust video surveillance. To achieve this, we propose a framework based on the idea of intrinsic images. Unlike previous methods of deriving intrinsic images, we derive time-varying reflectance images and corresponding illumination images from a sequence of images instead of assuming a single reflectance image. Using obtained illumination images, we normalize the input image sequence in terms of incident lighting distribution to eliminate shadowing effects. We also propose an illumination normalization scheme which can potentially run in real time, utilizing the illumination eigenspace, which captures the illumination variation due to weather, time of day, etc., and a shadow interpolation method based on shadow hulls. This paper describes the theory of the framework with simulation results and shows its effectiveness with object tracking results on real scene data sets.  相似文献   
2.
The idea of time slot interchange (TSI), the fundamental concept of implementing time switches in digital switching systems, was first conceived by Dr. Hiroshi Inose, then at the University of Tokyo, Japan, in 1957 while he was a visiting consultant at Bell Telephone Laboratories. The TSI collects each subscriber?s pulse code modulation (PCM)- coded voice information to be stored into a small time interval (time slot), and then aligns multiple time slots on a common transmission bus to constitute a repetitive frame. The TSI enables any time slot to be interchanged with another time slot within a frame once the time slots in the frame are buffered in memories. Thus, TSI gives the time switch functionality equivalent to Ninput by N-output space switch functionality. He built a prototype digital time-division multiplexing (TDM) electronic switching system called CAMPUS, which is based on the TSI principle, using a magnetostrictive delay line as a memory device. TSI received little attention until the end of the 1960s because memory devices were very costly. However, with the rapid advancement of semiconductor technologies in the 1970s, the TSI scheme became more widespread. TSI was first commercially deployed in 1976 as the time switch of AT&T?s no. 4 ESS, the world?s first stored-program control time-division switching system. Since then, TSI has been used in almost all digital central office switching systems and digital private branch exchanges (PBXs). Dr. Inose?s contributions were not limited to research on such things as switching systems, PCM integrated communications, computer communications, and road traffic control systems; he was also actively involved in a number of Japanese governmental and international activities in the area of communications and information processing technologies. His final work was the establishment of the National Institute of Informatics (NII) in 2000, Japan?s sole comprehensive academic institute in the field of informati  相似文献   
3.
ABSTRACT: The particular effect of 4 kinds of amino acid and peptide-rich food material (APRM) containing different charged amino acid contents on the gelatinization and retrogradation behavior of potato starch granules and on the water-vaporization behavior was analyzed by differential scanning calorimetry, rapid viscoanalysis, x-ray diffractometry, thermal gravimetry-differential thermal analysis, and pulsed NMR. APRM with a high-charged amino acid content produced unique gelatinization and retrogradation behavior in terms of an elevated gelatinization temperature, reduced viscosity, higher setback, and lower retrograded starch melting enthalpy. The recovered x-ray diffraction intensity decreased with increasing charged amino acid content. APRM with high-charged amino acid content could provide an improved paste having easy vaporization of external water in the swollen starch granules due to the reduced swelling.  相似文献   
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5.
A new multidimensional data structure, multidimensional tree (MD-tree), is proposed. The MD-tree is developed by extending the concept of the B-tree to the multidimensional data, so that the MD-tree is a height balanced tree similar to the B-tree. The theoretical worst-case storage utilization is guaranteed to hold more than 66.7% (2/3) of full capacity. The structure of the MD-tree and the algorithms to perform the insertion, deletion, and spatial searching are described. By the series of simulation tests, the performances of the MD-tree and conventional methods are compared. The results indicate that storage utilization is more than 80% in practice, and that retrieval performance and dynamic characteristics are superior to conventional methods  相似文献   
6.
Control algorithms of SONET integrated self-healing networks   总被引:2,自引:0,他引:2  
As the deployment of high-speed fiber transmission systems has been accelerated, they are widely recognized as a firm infrastructure of the information society. In SONET, the self-healing networks have been highlighted as one of the most advanced mechanisms used to realize SONET survivable networks. Several schemes have been proposed and studied due to the rapid progress in the development of highly intelligent network elements (NEs). A DCS based distributed self-healing network is discussed from the viewpoint of its control algorithms. The self-healing algorithm, called TRANS, is explained in detail. It possesses such desirable features as providing fast and flexible restoration with line and path level restoration applied to an individual STS-1 channel, the capability of handling multiple and even node failures, and so on. Both software simulation and hardware experiment verify that TRANS works properly in a real distributed environment, the result of which is shown in the paper. In addition, the combined use of TRANS and ring restoration control is proposed taking into account a practical SONET application  相似文献   
7.
Constructing Virtual Cities by Using Panoramic Images   总被引:1,自引:0,他引:1  
Simultaneously acquired omni-directional images contain rays of 360 degree viewing directions. To take advantage of this unique characteristic, we have been developing several methods for constructing virtual cities. In this paper, we first describe a system to generate the appearance of a virtual city; the system, which is based on image-based rendering (IBR) techniques, utilizes the characteristics of omni-directional images to reduce the number of samplings required to construct such IBR images. We then describe a method to add geometric information to the IBR images; this method is based on the analysis of a sequence of omni-directional images. Then, we describe a method to seamlessly superimpose a new building model onto a previously created virtual city image; the method enables us to estimate illumination distributions by using an omni-directional camera. Finally, to demonstrate the methods' effectiveness, we describe how we implemented and applied them to urban scenes.  相似文献   
8.
Traffic monitoring and accident detection at intersections   总被引:2,自引:0,他引:2  
We have developed an algorithm, referred to as spatio-temporal Markov random field, for traffic images at intersections. This algorithm models a tracking problem by determining the state of each pixel in an image and its transit, and how such states transit along both the x-y image axes as well as the time axes. Our algorithm is sufficiently robust to segment and track occluded vehicles at a high success rate of 93%-96%. This success has led to the development of an extendable robust event recognition system based on the hidden Markov model (HMM). The system learns various event behavior patterns of each vehicle in the HMM chains and then, using the output from the tracking system, identifies current event chains. The current system can recognize bumping, passing, and jamming. However, by including other event patterns in the training set, the system can be extended to recognize those other events, e.g., illegal U-turns or reckless driving. We have implemented this system, evaluated it using the tracking results, and demonstrated its effectiveness  相似文献   
9.
This paper proposes a distributed self-healing architecture which contains two self-healing techniques. In this proposal, a path restoration by Self-Healing Ring (SHR) and a path restoration by Dynamic Self-Healing (DSH) algorithm are jointly applied in a network. In the architecture, SHR is applied for a part of a path which is terminated by an Add-Drop Multiplexer (ADM), and DSH is applied for another part of a path which is terminated by two Digital Cross-Connect Systems (DCSs). Based on the architecture, DSH can be applied for a part of a path which is terminated by an ADM. Next, a network design algorithm is described in order to optimize the amount of spare capacity. As a result, spare capacity reduction is realized by using the algorithm for a network where the proposed architecture is applied.  相似文献   
10.
Renovascular hypertension in two sisters, aged 22 and 20, respectively, has been described. Renal artery stenoses were observed unilaterally in the elder patient and bilaterally in the younger one. In both patients, the functional significance of unilateral stenosis of the renal artery was documented by the renal vein renin ratio between the affected side and the contralateral or less affected side. High blood pressure and elevated plasma renin activity have been normalized with a unilateral revascularization in the elder patient, and with the treatment of propranolol in the younger one. The histological examination of the stenotic renal artery in the elder patient showed a finding comparable to the perimedial fibroplasia in Harrison and McCormack's classification of idiopathic fibromuscular stenosis.  相似文献   
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