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1985篇 您的检索式:期刊名="High Technology Letters"
    题名 作者 年代 出处 被引量
1Feedforward and Feedback Optimal Control for Linear Systems with Sinusoidal Disturbances显示文摘The linear systems affected by additive external sinusoidal disturbances is studied. The problem is to damp this forced oscillation in an optimal fashion. The main result of this paper is a new design approach is proposed of realizable feedforward and feedback optimal control law for a linear time invariant system with sinusoidal disturbances. The algorithm of solving the optimal control law is given. It is shown that the control law is easily realized and is robust with respect to errors produced by the external sinusoidal disturbances through simulation results.唐功友 2001High Technology Letters2001,7,4:38
2Improvement of the Mirror Extending in Empirical Mode Decomposition Method and the Technology for Eliminating Frequency Mixing显示文摘The mirror extending approach proposed by Zhao and Huang in EMD method is improved in this paper. Mirror extending manner of data is kept unchanged, but the approach for determining envelopes is changed. When the end of data is obviously not extremum, the envelope is determined by the first inner extremum and the image value in the mirror, ignoring the value on the end. This improvement eliminates the frequency compression near the end and decreases the error. Meanwhile, tridiagonal equations are used and the calculation speed is much increased. The temporal process curve is more important in reflecting the real physical process and comparable with other phenomena. Frequency mixing in IMFs makes it impossible. A high frequency reconstruction (HFR) approach is proposed to eliminate common frequency mixing and reconstruct an IMF with all high frequency portions. By this approach, the IMFs without frequency mixing are obtained to express significative processes. The high frequency information restored in high frequency IMF can be extracted by general spectrum method. After obtaining IMFs by EMD method, some of the theoretical and technological issues still exist when using the IMFs. The consistency of IMFs with real physical process is discussed in detail. By virtue of the approach proposed in this paper, the EMD method can be widely used in various fields.赵进平 2002High Technology Letters2002,8,3:30
3Biological activities of a neutral water-soluble agar polysaccharide prepared by agarase degradation显示文摘Depolymerization of agar was performed using agarase, which was extracted from the cell-free medium of a culture of marine bacterial Alteromonas sp. nov. SY 37-12. After ethanol fractionation and lyophilization, the water-soluble agar polysaccharide (WSAP3) was collected. The anti-tumor activity of the product was determined by using Sarcoma 180 tumor in mouse. The tumor inhibition rate of WSAP3 reached 48.7% at a dose of 64mg kg-1 after 15 days treatment. WSAP3 enhanced the activities of superoxide dismutase and catalase, which suggests that WSAP3 was effective in promoting the antioxidation ability and eliminating danger from free radicals. The result of flow cytometry showed that the WSAP3 had no activities of cell cycle inhibition or apoptosis-inducing activities. The anti-oxidation of WSAP3 was further confirmed by test in vitro, which might play an important role in anti-tumor activity. The immunological regulation of WSAP3, especially its effect on the phagocytosis ratio and phagocytosis index of macrophage was also assayed in test in vivo.王静雪 Mou Haijin Jiang Xiaolu Guan Huashi 2005High Technology Letters2005,11,4:24
4Detection of Grass Carp Hemorrhage Virus (GCHV) from Vietnam and Comparison with GCHV Strain from China显示文摘Grass carp plays an important role in small-scale aquaculture in Vietnam. However, a severe disease, known in Vietnam as 'Red Spot Disease', is causing significant economic loss in grass carp aquaculture. In this study, the tissue samples isolated from the grass carp with Red Spot Disease in Vietnam are investigated and comparied with the control GCHV isolated in China by experimental infection, culture cell infection, serological cross reactivity, and RT-PCR amplification. Infected grass carp exhibits hemorrhage symptoms about 5 days after experimental injection with GCHV-V (Vietnam) strain. The symptoms and lethality induced by the GCHV-V strain are identical to that induced by the Chinese GCHV-9014 strain. The Chinese GCHV-873 strain induces typical cytopathogenic effects in 4 cell lines, such as CIK, CAB, FHM and GCO, from the 6 fish cell lines examined. No cytopathogenic effects are observed in all the 6 examined cell lines, including CAB, FHM, CIK, EPC, CCO and GCO, infected by the GCHV-V strain and GCHV-9014 strain. Immunodiffusion assays demonstrate an obvious cross-reactivity among three GCHV strains. Precipitin lines are clearly observed not only between the anti-GCHV-873 serum and the two strains GCHV-873 and GCHV-9014, but also between the anti-GCHV-873 serum and the GCHV-V strain. GCHV can be detected by immunodiffusion assays after three generations of blind propagations in the cell lines inoculated by GCHV-V strain. This implicates that GCHV-V viruses have been replicated and amplified despite there being no cytopathogenic effects observed in these examined cell lines. Three genome segments of GCHV, including S8, S9 and S10, are amplified by three sets of PCR primers designed according to the segment sequences published recently. The Q8fp and Q8rp primer set specific for genome segment S8 amplifies a 955 bp fragment from the extracted sample of diseased fish with Red Spot Disease, and the fragment size is identical to that amplified by the same primer set from control GCHV-873 strain. Simultaneously, the Q9fp and Q9rp primer set specific for genome segment S9 generates a same 635 bp product, and the Q10fp and Q10rp primer set specific for genome segment S10 produces a same 697 bp fragment from both template samples of diseased fish with Red Spot Disease and control GCHV-873 strain. The RT-PCR amplification and corresponding size comparison data indicate that the three GCHV-V genome segments extracted from the diseased grass carp with Red Spot Disease in Vietnam should be identical to that in control GCHV-873 strain from China. The data confirm that the causative agent of grass carp Red Spot Disease in Vietnam is a virus, and the virus is closely similar to GCHV strain in China.张奇亚 Ruan Hongmei Li Zhenqiu Zhang Jing Gui Jianfang 2003High Technology Letters2003,9,2:20
5Study on ultracapacitor-battery hybrid power system for PHEV applications显示文摘熊瑞 He Hongwen Wang Yi Zhang Xiaowei 2010High Technology Letters2010,16,1:14
6The Synthesis of a Stewart Platform for a Specific Workspace with a Genetic Algorithm显示文摘The synthesis problem of a 6-SPS Stewart platform with semi-regular hexagons is studied in this paper. We present a genetic algorithm approach to synthesize a Stewart platform whose workspace must include a desired workspace with orienting capabilities in a given 3D region. Based on the observation that the constant orientation workspace gets smaller as the given orientations increase, a simple method is presented to describe the workspace with orienting capabilities, which need only search the constant orientation workspaces with the eight sets of extremal orientations of given 3D region and use their common part.To verify the method, a numerical example is given. The GA is used to optimize architectural parameters and obtain a compact manipulator. The method is applied to synthesize a Stewart platform whose workspace must include a prescribed cylinder with orienting capabilities.陈学生 Chen Zaili Xie Tiao 2004High Technology Letters2004,10,1:11
7Occurrence, Development and Histochemical Characteristics of Lymphocystis in Cultured Japanese Flounder (Paralichthys olivaceus)显示文摘Occurrence and development of lymphocystis cells in flounder Paralichthys olivaceus, and some histochemical features are studied using light and electron microscopy and histochemical methods. Fibroblasts engulf virus particles forming phagocytosis vacuole in the cytoplasm. The infected cells proliferate and turn round and hypertrophied; basophilic inclusion bodies, Feulgen-positive, are present in the cytoplasm, and a hyaline capsule, containing acid ploysaccharide and protein, appears outside cell membrane. The mature lymphocystis cells possess numerous virus particles (200~220nm in diameter with a central core 120~140nm) and high electron-dense inclusions with budding virions at the surface in the cytoplasm, and show margination of chromatin. Moderate electron density particles (70~80nm in diameter) fill out perinuclear cisterna and arrange in crystalloid arrays in nucleus, liberated into the cytoplasm by rupture of nuclear membrane. No virus particles are observed in nucleus. Therefore, inclusion bodies are the sites of virus assembly and maturity, while replication processes of lymphocystis virus are involved in both nuclear and cytoplasmic phases. Besides, strongly basophilic link-like structures are present between adjacent cells or through connective tissue, and virus particles are observed in somewhere of the capsule, thus where may be the spread route of virus from one cell to another or to the environment. The senile lymphocystis cells release virus by the rupture of cells.绳秀珍 Zhan Wenbin 2004High Technology Letters2004,10,2:10
8Phenotypic and genetic variation between two populations of the Chinese yellow pond turtle, Mauremys mutica (Cantor, 1842)显示文摘Mauremys mutica(Cantor,1842)is an endangered species in China.Main phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern populations.Both populations have the phenomenon of'larger male'sexualsize dimorphism(SSD),especially in the southern population.Furthermore,genetic variations betweenthe two populations were analyzed by RAPD band patterns of 30 random individuals in each population.The average genetic distance was 0.299±0.108 among the samples of two populations.The average ge-netic distance between southern and northern populations was 0.305±0.046.Cluster analysis indicatedthat all the individuals from the southern and northern populations were clustered among themselves toform two distinct clades.A total of 20 population-specific RAPD fragments were scored from 16 primers,and could be used as RAPD markers for distinguishing the southern and the northern population.Basedon the nucleotide sequences of two RAPD markers,two pairs of SCAR primers(SC1-S and SC2-S)weredesigned,which could be used as SCAR markers for the southern population.According to the significantphenotypic and genetic variations,we suggested that the northern population and southern populationmight be considered as two separate taxa,the'northern taxon'and the'southern taxon',and the con-servation should be respectively conducted on the two taxa.朱新平 Zhou Li Chen Yongle Du Hejun Gui Jianfang 2008High Technology Letters2008,14,1:10
9Genetic Diversity in Populations of Sepiella maindroni Using 16S rRNA Gene Sequence Analysis显示文摘Part of the 16S rRNA gene is amplified with PCR and sequenced for 5 populations of common Chinese cuttlefish Sepiella maindroni: three from the South China Sea, one from East China Sea and one from Japan. The result shows that a total of 5 nucleotide positions are found to have gaps or insertions of base pairs among these individuals, and 13 positions are examined to be variable in all the sequences, which range from 494 to 509 base pairs. All of the individuals are grouped into 7 haplotypes (h1-h7). No marked genetic difference is observed among those populations. All of the individuals from Nagasaki belong to h1 and the h3 haplotype is found only in the coastal waters of China. AG transition in Nucleotide 255 is suggested to be taken as a kind of genetic marker to identify the populations distributed in East-South China Sea and the Nagasaki waters of Japan.郑小东 WANG Rucai Xiao Shu Yu Ruihai Yang Jianmin 2003High Technology Letters2003,9,1:10
10Self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration显示文摘Kan Guangming Liu Baohua Zhao Yuexia Li Guanbao Pei Yanliang 2011High Technology Letters2011,17,3:9
11Transfer DREB into Lolium perenne L. to improve its drought tolerance显示文摘马欣荣 Sun Zhenyuan Jiang Changshun Dong Zhaoyong Zhang Yizheng 2006High Technology Letters2006,12,4:8
12Experimental study on vibration suppression of gear shaft misalignment with ISFD显示文摘Misalignment faults in gear systems lead to violent vibration and noise, shortening the life of equipment. The aim of this work is the demonstration of vibration suppression of parallel-misaligned gear shafts using an integral squeeze film damper(ISFD). Using a first grade spur gear in engineering for reference, an open first-grade spur gear system is built and the vibration characteristics of the gear system with rigid supports and ISFD elastic damping supports are studied under different degrees of misalignment. The experimental results show that ISFD supports have excellent damping and vibration attenuation characteristics, which have improved control of the gear system vibration in horizontal, vertical and axial directions under different degrees of misalignment. This work shows that an ISFD structure can effectively suppress vibration of characteristic frequency components and resonance modulation frequency components. The test results provide evidence for the application of ISFD in vibration control of gear shaft misalignment faults in engineering.路凯华 He Lidong Zhang Yipeng Chen Zhao Yan Wei 2019High Technology Letters2019,25,1:8
13Chinese multi-document personal name disambiguation显示文摘This paper presents a new approach to determining whether an interested personal name across documents refers to the same entity. Firstly, three vectors for each text are formed: the personal name Boolean vectors denoting whether a personal name occurs in the text, the biographical word Boolean vector representing title, occupation and so forth, and the feature vector with real values. Then, by combining a heuristic strategy based on Boolean vectors with an agglomerative clustering algorithm based on feature vectors, it seeks to resolve multi-document personal name coreference. Experimental results show that this approach achieves a good performance by testing on 'Wang Gang' corpus.Wang Houfeng(王厚峰) Mei Zheng 2005High Technology Letters2005,11,3:8
14Simulation and experimental study on lubrication characteristics of vertical hydrostatic guide rails显示文摘In order to improve the cutting stiffness,the paper studies the vertical hydrostatic bearing in the slide when a ram is in feed process.The change of the oil film thickness on hydrostatic guide rail and the curve of the oil film thickness in various cutting forces are calculated and a relation model through theoretical analysis method is derived.The pressure field of the guide rail recess is simulated based on the finite volume method and demonstrated through experiments.The study is of vital theoretical significance for the improvement of machining accuracy of numerical control machines and the entire computer numerical control(CNC) equipment and provides valuable theoretical basis for the design of hydrostatic guide rail in engineering practice.张艳芹 Yu Zeyang Chen Yao Shao Junpeng Yu Xiaodong Jiang Hui 2014High Technology Letters2014,20,3:8
15Construction of plateaued functions satisfying multiple criteria显示文摘A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application could be satisfied: balancedness, high nonlinearity, correlation immunity of reasonably high order, strict avalanche criterion, non-existence of non-zero linear structures, good global avalanche characteristics, etc.张卫国 2005High Technology Letters2005,11,4:7
16Parameters matching and optimization of parallel hybrid electric vehicle powertrain显示文摘陈勇 Chen Xiaokai Lin Yi 2010High Technology Letters2010,16,1:7
17Establishment of in Vitro Regeneration System of Bitter Melon (Momordica Charantia L. )显示文摘Explants of bitter melon can produce three types of callus: green, yellow green and fragile yellow callus. During the period of inducing callus, the explants are not sensitive to the kinds and proportions of phytohormone. The rate of callus inductivity is about 90.0%. However, in the process of callus differentiating adventitious bud, the kind, proportion and quantity of phytohormone and the type of callus made different result. The adventitious buds were induced successfully on MS medium+6-BA (N6-benzyladenine) 4.0 mg l-1+KT(kinetin) 2.0 mg l-1) by yellow green callus. The frequency was about 66.7 %. Yellow callus did not differentiated adventitious bud. The frequency of green callus differentiation was very low (<15.0 %) even under the most suitable conditions. The MS + ZT (zeatin) 5.0 mgl-1 +KT 0.5 mgl-1 medium was suitable for the proliferation of bud and three weeks later, the coefficient of proliferation was about 5-6. The 1/2 MS + ZT 0.02 mgl-1 or 1/2 MS media were suitable for in vitro rooting of shoot, the shoot on them could produce 6-7 new roots in three weeks. After plantation test, the survival rate of tube plantlets was about 70% and their characteristics were the same as those from seed by field test.杨满业 Zhao Maojun Zeng Yu Lan Liqong Chen Fang 2004High Technology Letters2004,10,1:7
18The study of antioxidant activities of fucoidan from Laminaria japonica显示文摘Two large molecular weight fucoidan fractions F-A and F-B were obtained by water extraction and anion-exchange chromatography and then L-A and L-B with low molecular weight and uronic acid content were prepared by radical process degradation of F-A and F-B. The antioxidant activities of the fucoidan fractions on two oxygen free radicals and Cu2+-induced low-density lipoprotein (LDL) oxidation were studied. The results show that all the fucoidan fractions had excellent scavenging capacities on superoxide radical and hypochlorous acid, except the highly sulfated fraction L-B. In LDL oxidation system, low molecular weight fractions L-A and L-B exhibited great inhibitory effects on LDL oxidation induced by Cu2+, however F-A and F-B had little inhibitory effects in this system due to their large molecular weights. The present results suggest that fucoidan from Laminaria japonica is an excellent natural antioxidant and has great potential for preventing the free radical-mediated diseases.ZhaoXue XueChanghu CaiYuepiao WangDongfeng FangYu 2005High Technology Letters2005,11,1:7
19A hierarchical algorithm for cyberspace situational awareness based on analytic hierarchy process显示文摘胡威 Li Jianhua Jiang Xinghao Zhang Yueguo Chen Xiuzhen 2007High Technology Letters2007,13,3:7
20Improved Roberts operator for detecting surface defects of heavy rails with superior precision and efficiency显示文摘An experimental platform accompanying with the improved Roberts algorithm has been developed to achieve accurate and real-time edge detection of surface defects on heavy rails.Detection results of scratching defects show that the improved Roberts operator can attain accurate positioning to defect contour and get complete edge information.Meanwhile,a decreasing amount of interference noises as well as more precise characteristic parameters of the extracted defects can also be confirmed for the improved algorithm.Furthermore,the BP neural network adopted for defects classification with the improved Roberts operator can obtain the target training precision with 98 iterative steps and time of 2s while that of traditional Roberts operator is 118 steps and 4s.Finally,an enhanced defects identification rate of 13.33%has also been confirmed after the Roberts operator is improved.The proposed detecting platform will be positive in producing high-quality heavy rails and guaranteeing the national transportation safety.石甜 Kong Jianyi Wang Xingdong Liu Zhao Xiong Jianliang 2016High Technology Letters2016,22,2:7
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