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Squeezing in the Thermal Jaynes-Cummings Model

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Chinese Physics Letters 1996年第6期13卷 432-435页

作者： XIE Rui-hua zou You-tao LIU Dun-huan Department of Physics Nanjing UniversityNanjing 210008 Department of Physics Wuhan UniversityWuhan 430072 National Laboratory of Solid State Microstructures Institute for Solid State Physics Center for Advanced Studies in Science and Technology of Microstructures Nanjing UniversityNanjing 210008

We have studied the influence of thermal photons on the symmetry between the field and atomic squeezing(SFAS)exposed in the resonant vacuum-field Jaynes-Cummings model with an initially coherent *** have shown that when the number of thermal photons(Nav)is less than 0.01,the SFAS is not sensitive to the presence of thermal photons;when Nav≥0.01,the broken SFAS can be seen;when Nav≥0.1,the squeezed atom cannot radiate a squeezed field any ***,we have discussed the possibility of detection of the boken symmetry in superconducting maser cavity.

关键词： symmetry Cummings resonant

Study on hydrodynamic vibration in fluidic flowmeter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1422-1428页

作者： WANG Chi-yu zou Jun FU Xin YANG hua-yong Institute State Key Laboratory of Fluid Power Transmission amt Control Zhejiang University Hangzhou 310027 China

The characteristics of the fluidic flowmeter,which is a combination of impinged concave wall and bistable fluid amplifier,is investigated by experimental studies and numerical simulations. The numerical approaches are utilized to examine the time dependent flow field and pressure field inside the proposed flowmeter. The effect of varying structural parameters on flow characteristics of the proposed fluidic flowmeter is investigated by computational simulations for the optimization. Both the simulation and experimental results disclose that the hydrodynamic vibration,with the same intensity,frequency and 180° phase shift,occurs at axisymmetric points in the feedback channel of the fluidic flowmeter. Using the structural combination of impinged concave wall and bistable fluid amplifier and differential signal processing technique,a novel fluidic flowmeter with excellent immunity and improved sensibility is developed.

关键词： Flowmeter Fluidic Hydrodynamic vibration Coanda effect

Analysis of the Load-Stress Response Characteristics of the Bogie Frame in Intercity Electric Multiple Unit

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 227-237页

作者： hua zou Shou-Guang Sun Qiang Li Zun-Song Ren Engineering Research Center of Structure Reliability and Operation Measurement Technology of Rail Guided Vehicles of Ministry of Education Beijing Jiaotong University

Load spectra research for bogie frame requires establishing the load?stress relationship on working condition, which has been omitted by the researchers. With the load?stress of the bogie frame of an intercity Electric Multiple Unit(Hereinafter referred to as EMU) as the research object, an optimization model of the load?stress transfer relationship is established. The load?stress coe cient for EMU bogie frame was calibrated in the laboratory bench and online test was arranged on Dazhou?Chengdu line. Comparison of nonlinear and linear neural networks proves that the linear transitive relation between the load and stress of the bogie frame in the operating process is highly suitable. An optimization model of the load?stress transfer coe cient is obtained. The data calculated with the modified coe cient are closer to the dynamic stress results in the actual operating process than the data calculated with the calibration coe cient. The coe cient of the modified transitive relation is una ected by operating area, empty load, heavy load, or other conditions in the operating process of the intercity EMU. The real loads in actual situations are obtained. The model of online load?stress relationship that is highly suitable for line stress calculation is finally established. The research is helpful for further damage calculation and inferring the time history signal of the load in load spectra research.

关键词： Bogie frame Load Stress Transitive relation Neural network

The small and large subunits of carbamoyl-phosphate synthase exhibit diverse contributions to pathogenicity in Xanthomonas citri ***

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Journal of Integrative Agriculture 2015年第7期14卷 1338-1347页

作者： GUO Jing SONG Xue zou Li-fang zou hua-song CHEN Gong-you School of Agriculture and Biology Shanghai Jiao Tong University

Carbamoyl-phosphate synthase plays a vital role in the carbon and nitrogen metabolism cycles. In Xanthomonas citrisubsp. citri, carA and carB encode the small and large subunits of carbamoyl-phosphate synthase, respectively. The deletion mutation of the coding regions revealed that carA did not affect any of the phenotypes, while carB played multiple roles in pathogenicity. The deletion of carB rendered the loss of pathogenicity in host plants and the ability to induce a hyper- sensitive reaction in the non-hosts. Quantitative reverse transcription-PCR assays indicated that 11 hrp genes coding the type Ill secretion system were suppressed when interacting with citrus plants. The mutation in carB also affected bacterial utilization of several carbon and nitrogen resources in minimal medium MMX and extracellular enzyme activities. These data demonstrated that only the large subunit of carbamoyl-phosphate synthase was essential for canker development by X. citri subsp, citri.

关键词： Xanthomonas citri subsp citri carbamoyl-phosphate synthase pathogenicity citrus canker hrp gene

Imidazolium ionic liquid as the background ultraviolet absorption reagent for determination of morpholinium cations by high performance liquid chromatography-indirect ultraviolet detection

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Chinese Chemical Letters 2014年第10期25卷 1371-1374页

作者： Hong Yu Yi-Meng Sun chun-Miao zou College of Chemistry and Chemical Engineering Harbin Normal University and Key Laboratory of Photonic and Electronic Bandgap MaterialsMinistry of Education

A novel analytical method was developed for determining morpholinium cations lacking ultraviolet absorption *** determination was carried out by high performance liquid chromatographyindirect ultraviolet（HPLC-1UV） detection using imidazolium ionic liquid as background absorption reagents,and imidazolium ionic liquid ***.-organic solvent as mobile phase by a reversed-phase C18 *** background ultraviolet absorption reagents,imidazolium ionic liquids and organic solvents were *** imidazolium ionic liquid in the mobile phase is not only the background ultraviolet absorption reagent for IUV,but also an active component to improve the separation of morpholinium *** was found that morpholinium cations could be adequately determined when0.5 mmol/L 1-ethyl-3-methylimidazolium tetrafluoroborate ***./methanol（80：20,v/v） was used as mobile phase with an IUV detection wavelength of 210 *** this study,the baseline separation of Nmethyl,ethylmorpholinium cations（MEMo） and *** cations（MPMo） was successfully achieved in 8.5 *** detection limits（S/N = 3） for MEMo and MPMo were 0.15 and0.29 mg/L,*** simple and practical method has been successfully applied to the determination of two morpholinium ionic liquids synthesized by the chemistry laboratory.

关键词： High performance liquid chromatography Indirect ultraviolet detection Imidazolium ionic liquids Morpholinium cations

Determination of tetraethyl ammonium by ion-pair chromatography with indirect ultraviolet detection using 4-aminophenol hydrochloride as background ultraviolet absorbing reagent

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Chinese Chemical Letters 2014年第2期25卷 201-204页

作者： chun-Miao zou Hong Yu Miao-Yu Wang College of Chemistry and Chemical Engineering Harbin Normal University and Key Laboratory of Photonic and Electronic Bandgap MaterialsMinistry of Education

A method was developed for the determination of tetraethyl ammonium （TEA） by reversed-phase ion- pair chromatography with indirect ultraviolet detection, Chromatographic separation was achieved on a reversed-phase C18 column using background ultraviolet absorbing reagent - ion-pair reagent - organic solvent as mobile phase. The effects of the background ultraviolet absorbing reagents, detection wavelength, ion-pair reagents, organic solvents and column temperature on the determination method were investigated and the retention rules discussed. Results found that TEA could be successfully analyzed by using 0.7 mmol/L 4-aminophenol hydrochloride and 0.15 mmol/L 1-heptanesulfonic acid sodium mixed with 20% （v/v） methanol as mobile phase at a UV detection wavelength of 230 nm. Under these conditions, the retention time of tetraethyl ammonium was 2.85 min. The detection limit （S/N = 3） for TEA was 0.06 mg/L. The relative standard deviations （n = 5） for peak area and retention time were 0.35% and 0.02%, respectively. The method has been successfully applied to the determination of synthesized tetraethyl ammonium bromide. Recovery of tetraethyl ammonium after spiking was 99.1%.

关键词： Ion-pair chromatography Indirect ultraviolet detection Tetraethyl ammonium 4-Aminophenol hydrochloride

Factors associated with fasting plasma ghrelin levels in children and adolescents

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World Journal of Gastroenterology 2008年第5期14卷 790-794页

作者： Chao-chun zou Li Liang Zheng-Yan Zhao Department of Endocrinology the Children's Hospital of Zhejiang University School of Medicine Hangzhou 310003 Zhejiang Province China

AIM:To measure plasma ghrelin levels in children and adolescents, analyze the associated factors, and investigate the role of ghrelin in obesity, insulin resistance and reproductive physiology. METHODS:A total of 283 subjects aged 4.8-15.8 year were enrolled. Fasting blood samples were collected and plasma ghrelin levels were measured by radioimmunoassay. Fasting glucose (FG), fasting insulin (FI), baseline testosterone (T), estradiol (E2), prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), serum total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT) and uric acid (UA) were measured. Body mass index (BMI), insulin resistance by homeostasis model (HOMA-IR) and beta cell function by homeostasis model (HOMA-β) were calculated. RESULTS:The median ghrelin level was 290 ng/L (15.0-1325.0 ng/L). Bivariate correlation analysis showed that ghrelin levels were inversely correlated with BMI, ALT, TG, UA, LH, FI and HOMA-IR (all P < 0.05). No other significant correlation was found between ghrelin levels and age, gender, TC, E2, FSH, PRL, FG and HOMA-β. Stepwise multiple regression analysis showed that only BMI and FI were independent determinants of plasma ghrelin levels in these children and adolescents (P = 0.018 and P = 0.046, respectively), which explained 25.4% of the variance. CONCLUSION:These data suggest that the lower ghrelin levels in obese subjects may be the result of obesity and hyperinsulinemia, which is very common in obese subjects. Moreover, ghrelin may regulate human reproductive physiology indirectly.

关键词： Ghrelin Obesity Body mass index Insulin

A Novel Method for Prediction of Protein Domain Using Distance-Based Maximal Entropy

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Journal of Bionic Engineering 2008年第3期5卷 215-223页

作者： Shu-xue zou Yan-xin huang Yan Wang chun-guang Zhou Key Laboratory of Symbol Computation and Knowledge Engineering of Ministry of Education College of Computer Science and Technology Jilin University Changchun 130012 P. R. China

Detecting the boundaries of protein domains is an important and challenging task in both experimental and computational structural biology. In this paper, a promising method for detecting the domain structure of a protein from sequence information alone is presented. The method is based on analyzing multiple sequence alignments derived from a database search. Multiple measures are defined to quantify the domain information content of each position along the sequence. Then they are combined into a single predictor using support vector machine. What is more important, the domain detection is first taken as an imbal- anced data learning problem. A novel undersampling method is proposed on distance-based maximal entropy in the feature space of Support Vector Machine （SVM）. The overall precision is about 80%. Simulation results demonstrate that the method can help not only in predicting the complete 3D structure of a protein but also in the machine learning system on general im- balanced datasets.

关键词： protein domain boundary SVM imbalanced data learning distance-based maximal entropy

Graph Embedding Based API Graph Search and Recommendation

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Journal of Computer Science & Technology 2019年第5期34卷 993-1006页

作者： chun-Yang Ling Yan-Zhen zou Ze-Qi Lin Bing Xie Key Laboratory of High Confidence Software Technologies Ministry of EducationBeijing 100871China School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

Searching application programming interfaces (APIs) is very important for developers to reuse software projects. Existing natural language based API search mainly faces the following challenges. 1) More accurate results are required as software projects evolve to be more heterogeneous and complex. 2) The semantic relationships between APIs (e.g., inheritances between classes, and invocations between methods) need to be illustrated so that developers can better understand their usage scenarios. To deal with these issues, we propose GeAPI, a novel graph embedding based approach for API graph search and recommendation in this paper. First, we build a software project’s API graph automatically from its source code and represent each API using graph embedding methods. Second, we search the API graph with a question in natural language, and return the corresponding subgraph that is composed of relevant code elements and their associated relationships, as the best answer of the question. In experiments, we select three well-known open source projects, JodaTime, Apache Lucene and POI, as examples to perform API search tasks. The experimental results show that our approach GeAPI improves F1-score by 10% compared with the existing shortest path based API search approach, while reduces the average response time about 60 times.

关键词： application programming interface (API) recommendation API graph graph embedding software reuse