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A new family of windows——convolution windows and their applications

Science china(Technological Sciences) 2005年第4期48卷 468-480页

作者： ZHANG Jieqiu1,2, LIANG Changhong1 & CHEN Yanpu3.1. Department of Applied Math. & Phys., college of Science, Airforce Engineering University, Xi’an 710051, china 2. National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi’an 710071, china 3. Computer Center, Xi’an Communication college, Xi’an 710106, china 1. Department of Applied Math. & Phys. College of Science Airforce Engineering University 710051 Xi’an China 2. National Key Laboratory of Antennas and Microwave Technology Xidian University 710071 Xi’an China 3. Computer Center Xi’an Communication College 710106 Xi’an China

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.

关键词： signal processing harmonic analysis window function convolution window synchronous error spoctral leakage

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Structural control of the Gagua “Wedge” Zone east of Taiwan Island on the southern Okinawa Trough

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Science china Earth Sciences 2005年第8期48卷 1165-1174页

作者： ZHENG Yanpeng1,2,3. LIU Baohua2,3. WU Jinlong2, LIANG Ruicai2,3. LIU Chenguang2,3.& ZHANG Zhengmin1 1. Marine Geology college, Ocean University of china, Qingdao 266003. china 2. First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 3. Key Laboratory of Marine Sedimentology and Environmental Geology, State Oceanic Administration, Qingdao 266061, china 1. Marine Geology college Ocean University of China 266003 Qingdao China 2. First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 3. Key Laboratory of Marine Sedimentology and Environmental Geology State Oceanic Administration 266061 Qingdao China

Based on compositive analysis and interpretation of the observed and historical data, the geophysical field characters and structural properties of the Gagua “Wedge” Zone of the sea area east of Taiwan Island and the primary tectonic stress direction and its variabilities of backarc spreading in the southern Okinawa Trough are studied. It is concluded from the study results that the Gagua “Wedge” Zone is structurally consistent with the Gagua ridge and two fault basins on both sides of the Gagua ridge, and adjusts the moving direction and distance of the western Philippine Sea plate to make the northwestward motion of the plate on its east side change to the northward subduction of the plate on its west side so that the primary tectonic stress direction of the Okinawa Trough changed from NW-SE to nearly N-S, which provided the stress source for the Okinawa Trough to enter the second spreading stage.

关键词： east of Taiwan Island, Gagua "Wedge" Zone, Okinawa Trough, structural control.

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Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical Science, Chongqing Normal University, Chongqing 400047, china 2 college of Resources and Environmental Science, Chongqing University, Chongqing 400044, china 3.college of Resources Science & Technology, Beijing Normal University, Beijing 100875, china college of Geographical Science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental Science Chongqing University Chongqing 400044 China college of Resources Science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural Science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2, Lian Linsheng3. Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal Science and Technology, china Agricultural University, Beijing 100094, china 2. college of Biological Science, china Agricultural University, Beijing 100094, china 3. college of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, china) college of Animal Science and Technology China Agricultural University Beijing 100094 China college of Biological Science China Agricultural University Beijing 100094 China college of Animal Science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

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Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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Science china(Technological Sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1,3. LIU Zhilin1, ZHANG Chengwei1,2 & ZHOU Yingchun1 1. Liaoning Institute of Technology, Jinzhou 121001, china 2. china National Oil and Gas Exploration and Development Corporation, Beijing 100011, china 3. {3. of Science, Northeastern University, Shengyang 110006, china 1. Liaoning Institute of Technology 121001 Jinzhou China 2. college of Science Northeastern University 110006 Shengyang China 3. china National Oil and Gas Exploration and Development Corporation 100011 Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

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Pulmonary embolism and deep venous thrombosis in china

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Journal of Geriatric Cardiology 2024年第8期21卷 775-778页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual Report on Cardiovascular Health and Diseases in china(2022) intricate landscape of cardiovascular health in *** connection with the previous section,this eighth section of the report offers a comprehensive analysis of pulmonary embolism and deep venous *** recent years,research in the field of pulmonary vessel in china has made great progress.A number of nationwide multi-center registry research results have filled the gaps in the epidemiology,diagnosis and treatment of pulmonary hypertension and venous *** types of pulmonary hypertension still need attention to the identification of risk factors and/or risk stratification,and venous thromboembolism needs attention in the prevention and the overall management inside and outside *** the future,we look forward to the publication of more high-quality research in china,which could be able to improve relevant guidelines for pulmonary vascular diseases both domestically and inter-nationally.

关键词： epidemiology prevention diagnosis

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3. building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2,XIA YuBin 2,WU Lun 3.& SUI ZhengWei 3.1 college of Software,Beihang University,Beijing 100191,china 2 college of Computer,Beihang University,Beijing 100191,china 3.Institute of Remote Sensing and GIS,Peking University,Beijing 100871,china Beihang Univ Coll Software Beijing 100191 Peoples R China Beihang Univ Coll Comp Beijing 100191 Peoples R China Peking Univ Inst Remote Sensing & GIS Beijing 100871 Peoples R China

The real world is a three-dimensional(3.)space requiring that 3. geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3. building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3. geospatial data on the web.3. city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3. building model,an abstract of a 3. building model based on structure details is studied,and a novel representation approach named 3. transparent building hierarchical model is presented in this *** approach fully uses both the existing 3. modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3. *** addition,based on the characteristics of the 3. building model data,a service-oriented architecture and Web service technologies for 3. city building models are *** aim of the approach is that 3. city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3. modeling 3. transparent building hierarchical models china Star web services

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Anticancer effect of two diterpenoid compounds isolated from Annona glabra Linn

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Acta Pharmacologica Sinica 2004年第7期25卷 91-96页

作者： Yong-hong ZHANG2, Hai-yan PENG3. Guo-hao XIA3. Ming-yan WANG3. Ying HAN4 First Clinical college 3.asic Medicine college, Nanjing University of TraditionalChinese Medicine, Nanjing 210029 4Jiangsu Institute of Materia Medica, Nanjing 210009, china First Clinical college Basic Medicine college Nanjing University of Traditional Chinese Medicine Jiangsu Institute of Materia Medica

AIM: To study the inhibitory effect of two diterpenoid compounds isolated from Annona glabra Linn (Cunabic acid and ent-kauran-19-al-17-oic acid) on the proliferation of Human Liver Cancer (HLC) cell line SMMC-7721 and its mechanism. METHODS: Inhibition of cell proliferation was measured by MTT assay. The morphological changes of SMMC-7721 cells were observed under inverted phase-contrast microscope, fluorescent microscope, transmission electron microscope (TEM), and scanning electron microscope (SEM). Flow cytometer (FCM) was used to calculate the cell apoptotic rate, and immunohistochemical staining was used to observe the regulation of gene expression. RESULTS: The proliferation of SMMC-7721 cells was obviously inhibited after being treated with Cunabic acid at the concentration >5 μmol/L and ent-kauran-19-al-17-oic acid >10 μmol/L. The biggest inhibitory effect was 81.05 % when treated with Cunabic acid at the concentration of 25 μmol/L. The effect had a linear relationship with concentration. The result indicated that drug-treated cells exhibit typical morphological changes of apoptosis, including condensed chromatin and a reduction in volume. Sub-G0/G1 peak was found by FCM analysis and the cell cycle was arrested at G0/G1 stage. The apoptotic rates of the cells treated by Cunabic acid and ent-kauran-19-al-17-oic acid were 43.3. % and 24.95 %, respectively. It was visualized by immunohis- tochemical staining that the drugs down-regulated the gene expression of bcl-2 gene and up-regulated that of bax gene. CONCLUSION: The two diterpenoid compounds isolated from Annona glabra Linn, Cunabic acid and ent- kauran-19-al-17-oic acid can obviously inhibit the proliferation of HLC cell line SMMC-7721. The mechanism is correlated with the induction of cell apoptosis by down-regulating the gene expression of bcl-2 gene and up- regulating that of bax gene.

关键词： Annona glabra Linn diterpenes hepatocellular carcinoma apoptosis gene expression

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Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3.1. School of Surveying and Landing Information Engineering, Henan Polytechnic University, Jiaozuo 454003. china 2. college of Geoscience and Surveying Engineering, china University of Mining and Technology, Beijing 100083. china 3. Surveying and Mapping Press, Beijing 100045, china [a] School of Surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] college of Geoscience and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

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Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3. GU Fang1 & BA Xinwu1 1. college of Chemistry and Environment Science, Hebei University, Baoding 071002, china 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, china 3. college of Physics Science and Technology, Hebei University, Baoding 071002, china 1. college of Chemistry and Environment Science Hebei University Baoding 071002 China 2. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China 3. college of Physics Science and Technology Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

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