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51.
The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed,and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing success ratio as compared with other existing algorithms,and performs excellently in delay variation performance under lower time complexity,which ensures it to support the requirements of real-time multimedia communications more effectively. 相似文献
52.
The uniformity of two pairs of color spaces based on CIE 1997 color appearance model (CIECAM97s) is analyzed according to color-discrimination ellipses that are constructed using color-difference evaluation data. A new uniform color space named Jucs a ucs b ucs is deduced by re-scaling the coordinates of lightness, redness-greenness and vellowness-blueness in two initial color spaces using linear regression method. The uniformity of the new color space is obviously improved compared with the initial color spaces. 相似文献
53.
Sonication is a powerful technique to promote the dispersion of carbon nanotubes(CNTs) and enhance their solubility;this is necessary for CNT applications,especially in the biochemical and biomedical fields.In this study,batch experiments were conducted to evaluate the role of sonication energy on the dispersion of CNTs in the presence of a widely used anionic surfactant,sodium dodecylbenzene sulfonate(SDBS).It was observed that the concentration of dispersed CNTs in the SDBS solution depended on the sonication energy,but not the sonication time or output power of the sonicator alone.The amount of dispersed CNTs was positively correlated with the concentrations of SDBS and CNTs,and the length of the CNTs.The promotion of oxygen-containing functional groups on the dispersed CNTs was observed at relatively low sonication energies.The optimal energy,i.e.the minimum energy supplied by sonication to achieve a saturated suspension of dispersed CNTs in the SDBS solution,was CNT diameter-dependent,because of the larger vdW forces between tubes of smaller diameter.An exponential decay curve was constructed for the optimal energy values as a function of the outer CNT diameter,to assist in determining the energy needed to disperse CNTs. 相似文献
54.
LI Haiyan TANG Beish XIA Kun CAO Guifang SHEN Lu JIANG Hong PANQian SONG Yanmin CAI Fang 《自然科学进展(英文版)》2005,15(8):757-760
Benign familial neonatal convulsions (BFNC) is a rare autosomal dominant inherited epilepsy syndrome. Two voltage-gated potassium channel genes, KCNQ2 and KCNQ3, have been identified as the genes responsible for BFNC. Here we report two Chinese families with clinical histories of typical BFNC. Using six microsatellite markers, two located at KCNQ2 locus and four at KCNQ3 locus, linkage analysis was performed in the two families, which excluded the linkage of BFNC to KCNQ3, but could not exclude the linkage to KCNQ2. Direct DNA sequencing of the KCNQ2 gene in the two families was performed, and two formerly unknown polymorphisms were identified, but no KCNQ2 mutation was found in the two families. Our study suggests the genetic heterogeneity in Chinese families with BFNC and proves the existence of a new gene locus for BFNC. 相似文献
55.
WANG Kun SU Rui-dan LI Zeng-xin CAI Zhen ZHOU Li-hua 《武汉大学学报:自然科学英文版》2006,11(1):170-174
Highly security-critical system should possess features of continuous service. We present a new Robust Disaster Recovery System Model (RDRSM). Through strengthening the ability of safe communications, RDRSM guarantees the secure and reliable command on disaster recovery. Its self-supervision capability can monitor the integrality and security of disaster recovery system itself. By 2D and 3D rea-time visible platform provided by GIS, GPS and RS, the model makes the using, management and maintenance of disaster recovery system easier. RDRSM possesses predominant features of security, robustness and controllability. And it can be applied to highly security-critical environments such as E-government and bank. Conducted by RDRSM, an important E-government disaster recovery system has been constructed successfully. The feasibility of this model is verified by practice. We especially emphasize the significance of some components of the model, such as risk assessment, disaster recovery planning, system supervision and robust communication support. 相似文献
56.
TANG Beisha LUO Wei ZHAO Guohua XIAO Jianfeng LI Qi MA Yanlin XIA Kun YANG Qidong 《自然科学进展(英文版)》2003,13(6)
The form of Charcot-Marie-Tooth (CMT) neuropathy that maps to Xql3 is X-linked dominant, or X-linked intermediate. Heterozygous females are more mildly affected than hemizygous males. It has been known that this type of CMT is caused by mutations of connexin32 (Cx32) gene. A typical X-linked recessive Charcot-Marie-Tooth Chinese family was analyzed with single strand conformation polymorphism method. A Cx32 gene point mutation, ArglSGln, in exon 2 was identified in all affected family members, suggesting that this mutation is responsible for the CMT incidence of this family. 相似文献
57.
LIU Zhaoyu ZHANG Wenli ZHENG Jingyue GUO Shisheng CUI Guolong KONG Lingjiang LIANG Kun 《系统工程与电子技术(英文版)》2023,(5):1171-1181
This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar. Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results. Firstly, an electromagnetic(EM) wave NLOS multipath propagation model for vehicle scene is established. Subsequently, with the help of available multipath echoes, a complete NLOS vehicle localization algorithm is proposed. Finally, simulation and experimental results validate t... 相似文献
58.
Through a modified agar well diffusion assay, antagonism of bacterium BS04 is tested. The data show that BS04 has antibiotic activity against phytopathogenic fungi and bacteria, including Phoma wasabiae Yokogi, Cochlibolus Heterostrophu, Exserohilum Turcicum, Curuvularia Lunata (Walk) Boed, Thantephorus cucumris, Fusarium graminearum, Xanthomonas axonopodis pv. Citri (Hasse) Dye and Xanthomonas zingiberi (Uyeda ) Savulescu. The products of bacterium BS04 can endure the treatment of a wide range of pH, and maintain the antibiotic activity after treatment of 100℃ for 30 min. The result suggests that bacterium BS04 has the potential as a promising biocontrol agent. In order to determine the taxonomic placement, the molecular identification of BS04 is performed. The comparative analysis of 16s rDNA sequences indicates that the 16s rDNA sequence of BS04 is highly homologous with sequences of typical Paenibacillus bacteria from the RPD library (from 92% to 99% ). And the constructed phylogenetic tree by using maximum-likelihood method with Bootstrap Trial 1000 proves that BS04 is subjected to Paenibacillus polymyxa. 相似文献
59.
Xi-jin TANG Kun NIE Yi-jun LIU Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing P. R. China School of Knowledge Science Japan Advanced Institute of Science Technology - Asahidai Ishikawa - Japan 《系统科学与系统工程学报(英文版)》2005,14(4):476-494
1 Introduction Transportation is a basic and indispensable element in social economic development Great achievements have been reached intransportation in China since the adoption of reform and opening policy in 1978 To meet the continuously increasing demands from the socioeconomic development for a harmony andwell-off living society, a national integrative transportation system instead of separate planning by individual transport mode has been under consideration to deal with old and emergin… 相似文献
60.
The real-time performance of switched Ethernet is a hot research field. However, there isn't any effective modeling to describe it until now. Through analyzing the structure of classical switch, a switch model by network calculus is proposed, in which the data flow is divided into real-time flow and non real-time flow and the arrival curve, service curve, the max delay and max storage needed are got. The max delay provides theory direction for transmitting real-time data in switched Ethemet and the max storage provides the theory reference for constructing switch in real-time industrial Ethernet. 相似文献