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排序方式: 共有3478条查询结果,搜索用时 15 毫秒
211.
本文在分析钻井废物特性的基础上,选用水泥基和石灰基两种固化体系,以烟灰、蒙脱土为添加剂进行固化试验。实验表明,经处理后的钻井废物,重金属铬和COD的浸出量都降低了95%以上,产物稳定性好,从而能减少它对环境的污染。文中还讨论了影响固化效果的一些因素。 相似文献
212.
Mandeep M. Sahani Tarek M. Daoud Ramin Sam Jerry Andrews Yuk Lun Cheng Carl M. Kjellstrand Todd S. Ing 《Hemodialysis international. International Symposium on Home Hemodialysis》2001,5(1):92-96
An aggressive dialysis in a grossly azotemic patient, especially one with severe metabolic acidosis, can lead to dialysis disequilibrium syndrome (DDS). Mild forms present as nausea, vomiting, restlessness, and headache. Severe manifestations include seizures, obtundation, coma, and even death. This clinical picture is caused by cerebral edema induced by one or more of the following mechanisms:
- 相似文献
213.
A novel autofocus algorithm for synthetic aperture radar (SAR) based on total variation is presented in this paper. The method,
which starts with a complex phasedegraded SAR image, after the phase errors model is introduced into the range-compressed
phase-history domain, carries out phase errors correction by changing the focus till the total variation of the azimuth profile
is maximized. Compared with the minimum entropy autofocus algorithm, the autofocus algorithm has less computational complexity
and is easier to implement. The simulation and the processing results of the measured data show the validity of the proposed
method.
Translated from Journal of Xidian University, 2006, 33(2): 167–172 [译自: 西安电子科技大学学报] 相似文献
214.
215.
Reconfigurable Microwave Photonic Filter Using Multiwavelength Erbium-Doped Fiber Laser 总被引:1,自引:0,他引:1
Xinhuan Feng C. Lu H.Y. Tam P.K.A. Wai 《Photonics Technology Letters, IEEE》2007,19(17):1334-1336
A microwave photonic filter using a simple and novel multiwavelength erbium-doped fiber laser (EDFL) is proposed. The filter was experimentally demonstrated featuring tunability and reconfigurability by adjustment of the output from the EDFL. The experimental results show excellent agreement with the numerical simulations. 相似文献
216.
Tai-Chiu Hsung Pak-Kong Lun D. Wan-Chi Siu 《IEEE transactions on image processing》1998,7(10):1488-1496
We introduce a deblocking algorithm for Joint Photographic Experts Group (JPEG) decoded images using the wavelet transform modulus maxima (WTMM) representation. Under the WTMM representation, we can characterize the blocking effect of a JPEG decoded image as: (1) small modulus maxima at block boundaries over smooth regions; (2) noise or irregular structures near strong edges; and (3) corrupted edges across block boundaries. The WTMM representation not only provides characterization of the blocking effect, but also enables simple and local operations to reduce the adverse effect due to this problem. The proposed algorithm first performs a segmentation on a JPEG decoded image to identify the texture regions by noting that their WTMM have small variation in regularity. We do not process the modulus maxima of these regions, to avoid the image texture being "oversmoothed" by the algorithm. Then, the singularities in the remaining regions of the blocky image and the small modulus maxima at block boundaries are removed. We link up the corrupted edges, and regularize the phase of modulus maxima as well as the magnitude of strong edges. Finally, the image is reconstructed using the projection onto convex set (POCS) technique on the processed WTMM of that JPEG decoded image. This simple algorithm improves the quality of a JPEG decoded image in the senses of the signal-to-noise ratio (SNR) as well as the visual quality. We also compare the performance of our algorithm to the previous approaches, such as CLS and POCS methods. The most remarkable advantage of the WTMM deblocking algorithm is that we can directly process the edges and texture of an image using its WTMM representation. 相似文献
217.
The near-field thermomechanical response of an immobilized waste disposal vault in crystalline hard rock was numerically studied taking into account the nonlinear behaviour of the host rock. The results of analyses indicate that the temperature dependence of rock properties has relatively little effect on the transient temperature distributions but may increase the thermal stresses and displacements substantially. However, no deep-seated major overstressed zones are expected. 相似文献
218.
219.
In open railway access markets, a train service provider (TSP) negotiates with an infrastructure provider (IP) for track access rights. This negotiation has been modeled by a multiagent system in which the IP and the TSP are represented by separate software agents. One of the tasks of the IP agent is to generate feasible (and preferably optimal) track access rights, subject to the constraints submitted by the TSP agent. This paper formulates an IP-TSP transaction and proposes a branch-and-bound algorithm for the IP agent to identify the optimal track access rights. Empirical simulation results show that the model is able to emulate rational agent behaviors. The simulation results also show good consistency between the timetables that were attained from the proposed methods and those that were derived by the scheduling principles adopted in practice. 相似文献
220.