Subjects: Statistics >> Social Statistics submitted time 2024-03-27 Cooperative journals: 《中国科学院院刊》
Abstract： The measurement of national science and technology competitiveness helps to describe the international competition pattern, and to provide decision-making reference for future-oriented science and technology policy and strategy formulation. From the perspective of input-process-output, the study proposes a three-dimensional measurement framework of potential-efficiency-strength for national science and technology competitiveness and realizes a multi-dimensional comprehensive measurement of national science and technology competitiveness, which takes the differences in both scale and efficiency into account. Based on The Report on National Science and Technology Competitiveness 2023, the study measures the national science and technology competitiveness of 34 major countries in the world and focuses on the evolution trend of national science and technology competitiveness of 11 countries including China from 2011 to 2022. On this basis, the science and technology competitiveness of 34 countries is further classified and analyzed from the three dimensions of science and technology competitiveness potential, science and technology competitiveness effectiveness, and science and technology competitiveness strength, so as to describe the technological competition pattern of 34 countries and reveal the status quo of China’s science and technology competitiveness. The research has found that the growth rate of China’s science and technology competitiveness has gradually slowed down in recent years, shifting towards a stage of steady growth. However, there is still significant room for improvement compared to leading countries. Among them, the level of China’s science and technology competitiveness strength is relatively high, but the indicators that reflect the quality of China’s technological output are still far from those of major technological powers. China’s science and technology competitiveness potential has improved but the level of intensity indicators is still lower than those of main technological powers. The significant decrease in the science and technology competitiveness effectiveness compared to major technological powers is the main factor restricting the improvement of China’s science and technology competitiveness. Finally, this study puts forward suggestions to improve China’s science and technology competitiveness.
Subjects: Management Science >> Other Disciplines of Management Science submitted time 2023-07-09 Cooperative journals: 《中国科学院院刊》
Abstract： Changes in international development environment such as geopolitics, geo-economics and science and technology innovation are reshaping the world’s competitive landscape and altering the balance of power among nations. China needs to adapt to the changes in international development environment, accurately grasp the new trends, optimize and adjust the science and technology strategy, effectively respond to new challenges, and seek new advantages in international competition. This study reviews China’s choices of science and technology strategy under the changes in international development environment. By summing up the successful experiences and remaining issues of the past science and technology strategies, the study proposes new choices for China’s science and technology strategy in response to new international development environment. It is found that, China’s science and technology strategy has been continuously adjusted and optimized in response to the ever-changing international development environment. Successful experience such as engaging in international scientific and technological cooperation, formulating forward-looking and systematic policies, improving the construction of national innovation system, fully leveraging the advantages of the nationwide system, or advancing reform of systems and mechanisms for science and technology, have effectively addressed the complex and changing international development environment and propelled the rapid development of China’s scientific and technological endeavors. However, China still needs to deal with and resolve the remaining issues in science and technology strategy choices, such as the path dependency of critical core technologies, the lack of deep integration between innovation and industrial, the lack of synergy among “education,science, technology and talent”, and the non-principal role of enterprises in innovation. Facing the new round of technological revolution and industrial transformation, the acceleration of deglobalization and regionalism, the rise of developing countries as a collective force, and the increasingly intense international conflicts and confrontations, China’s science and technology strategy should learn from historical retrospection and strengthen strategic foresight and form asymmetric advantages, enhance the development of a national self-reliant innovation ecosystem, and promote science, improve the new nationwide system to strengthen the basic capabilities of science and technology, and technology cooperation in the light of diverse international interests.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Based on the innovation value chain, this study establishes the “three horizontal and two vertical dimensions” measurement framework of National Innovation Force, which has a science-technology-industry horizontal dimension and a strength-effectiveness vertical dimension. The framework realizes a comprehensive analysis of National Innovation System from different perspectives and supports the categorized research and differentiated implementation of innovation policies and strategies. The framework considers the differences in science, technology, and innovation activities, as well as those between strength and effectiveness. Based on the analysis of 35 countries in The Report of National Innovation Force Measurement and International Comparison completed by the authors, this work studies in depth the evolution of National Innovation Force of China and ten typical countries from 2006 to 2020. In addition to the competitive landscape of National Innovation Force of 35 countries, it analyzes the advantages and disadvantages of China’s National Innovation Force during the period. As a result, it shows that the competitive landscape of National Innovation Force of 35 countries has changed slightly. China’s National Innovation Force ranking has increased steadily but still needs to be improved. From the comparison between China and ten typical countries, six developed countries, namely the United States of America, Japan, Germany, the United Kingdom, France, and South Korea, generally had high National Innovation Strength Force rankings. But their National Innovation Effectiveness Force rankings dropped from upper to the middle level, leading to the drop in National Innovation Force rankings of countries such as the United Kingdom and France in recent years. Four BRICS countries, namely South Africa, India, Brazil, and Russia were in the middle or lower level of National Innovation Strength Force rankings. Besides, their National Innovation Effectiveness Force ranked low, which restricted the improvement of their National Innovation Force rankings. China’s National Innovation Strength Force ranked among the top level of 35 countries and had obvious advantages. Despite some fluctuations, China’s National Innovation Effectiveness Force ranking rose to the middle level of 35 countries in 2020. However, China’s National Innovation Effectiveness Force ranking significantly lagged behind China’s National Innovation Strength Force ranking and restricted the improvement of China’s National Innovation Force ranking. From the perspective of three types of innovation activities, different from ten typical countries’ stable or declining trends, China’s National Technological Force ranking, National Scientific Force ranking, and National Industrial Force ranking were all on the rise. For China, the competitive advantage of National Technological Force became increasingly significant, while National Scientific Force was the key constraint force. In the future, some measures should be taken to enhance China’s National Innovation Force.
Subjects: Psychology >> Cognitive Psychology submitted time 2021-10-13
Abstract： Physiognomy is an important factor in identifying and inferring the individual traits and behaviors. However, its internal mechanism still needs to be further explored. Based on general cognitive perspective and evolutionary cognitive perspective, then combined with the local and overall features of physiognomy, this paper expounds the process and effect of judging people by physiognomy. Based on the general cognitive perspective, physiognomy affects the recognition of individual traits through various cognitive processing systems, and these traits play important roles in judgment (ability, income, social hierarchy) and decision-making (trust, recruitment, promotion). Based on the perspective of evolutionary cognition, physiognomy plays an important role in evaluating individual health and genetic status through various evolutionary selection mechanisms, and thus has an important influence on judgment (marriage satisfaction, happiness, life satisfaction) and mate selection decision. In addition, the effect of physiognomy on individual life depends on the situations and individual traits. Future research should investigate the interaction among different physiognomy features, and explore the boundary conditions that influence the effect of facial recognition. Furthermore, it is necessary to improve the external validity of the research through big data analysis, and pay more attention to physiognomy features modified by epigenetics on individuals. It is also important to conduct research within the domestic context. In doing so, it will help enrich physiognomy-related research and build a more systematic physiognomy theory. " "
Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] This paper takes "Sci-Think" as an example to analyze the measures and results of emergency scientific communication services of the special libraries, and provides reference for scientific communication services of professional libraries in emergency situations.[Method/process] To sort out the service contents published by the "Sci-Think" WeChat public account during the epidemic, this paper analyzed users' attention to different types of contents from average daily user growth and reading volume, and put forward the thinking of emergency scientific communication services.[Result/conclusion] During the epidemic, Sci-Think's average daily user growth was obvious, with the highest reading volume of electronic resource protection content, followed by related content of the scientific and technological progress of COVID-19, and the number of popular science broadcasts and information quality education broadcasts exceeded tens of thousands. Under emergencies, special libraries should strengthen the promotion of special services, strengthen the information selection and review mechanism, and the lack of emergency scientific communication work plans in major public incidents also needs attention.
Subjects: Statistics >> Social Statistics submitted time 2024-03-27 Cooperative journals: 《中国科学院院刊》
Abstract： In today’s rapidly advancing technological landscape, science communication is closely intertwined with technological innovation, serving as a crucial element in influencing a country’s technological competitiveness and competing for the global scientific and technological discourse. This study delves into the historical context of science communication and the theoretical research and paradigm shifts surrounding it. It explores the symbiotic relationship between science communication and technological innovation, uncovering the mechanisms of their interactions. On this basis, the study examines exemplary practices in promoting science communication in major developed countries. In light of China’s current state of science communication, tentative strategies are proposed to enhance the nation’s endeavors in the realm of science communication.
Subjects: Hydraulic Engineering >> Basic Disciplines of Hydraulic Engineering submitted time 2021-01-25
Abstract： The ecological environment of the Yellow River Basin is systematic and complicated. It is of great significance to study the quantitative evaluation and change characteristics of the Yellow River Basin by providing scientific basis on integrated river basin management. This in one of the current widespread concerns and urgent problems to be solved. Through calculating the entropy weights of eco-environmental indicators in Yellow River Basin from 1980 to 2019, the dynamic entropy weight results were verified. Then the importance of the individual indicator in system was proved to be variable. On this basis, the EDIs (Environment Development Indexes) of the Yellow River Basin from 1980 to 2019 were analyzed and plotted by curve, which valued between 56.64～76.60. The changing trend of EDI in the Yellow River Basin was almost presented stabilized before 2003, and continuously increasing from 2003. The results show that through the years of protection and restoration, the ecological negative feedback was exerted profound effect, resulting the ecological environment of the Yellow River Basin was changing well.
Peer Review Status:
Awaiting Review
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To evaluate the effect of ulinastatin on hypoxia-induced phenotype modulation of pulmonary artery smooth muscle cells (PASMCs) and explore the underlying mechanism. Method Cultured PASMCs from SD rats were exposed to normoxic condition, normoxia with ulinastatin treatment, hypoxia, or hypoxia with ulinastatin treatment. After 24 h of exposures, the cells were examined for SM-α-actin and caplonin expressions with immunofluorescence assay and for cell migration with CCK-8 and 3H-TdR assays. Western blotting was used for detecting the expressions of PPAR-γ in the cells, and PPAR-γ-responsive firefly luciferase reporter was employed for measuring the transcriptional activity of PPAR-γ. The PPAR-γ inhibitor GW9662 was used to explore the mechanism of the inhibitory effect of ulinastatin on hypoxia induced-phenotype modulation of PASMCs by measuring the changes in cell proliferation and migration. Results Ulinastatin obviously enhanced the expressions of SM-α-actin and calponin (P<0.05), inhibited the proliferation and migration (P<0.05), and up-regulated the expression of PPAR-γ in PASMCs exposed to hypoxia (P<0.05). Pretreatment of the cells with GW9662 abolished the effect of ulinastatin on hypoxia-induced phenotype modulation of PASMCs and enhanced the cell proliferation and migration (P<0.05). Conclusion Ulinastatin inhibits hypoxia-induced phenotype modulation of PASMCs from rats possibly by up-regulating the expressionofPPAR-γ.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Under the new situation, expanding and strengthening the crop seed industry and ensuring food security have been elevated to the national strategic importance. It urgently needs to improve the crop seed national innovation system and promote the deep integration of the innovation chain and industrial chain. The crop seed industry in developed countries such as the United States has formed a relatively mature industrial innovation system dominated by enterprises; however, China’s crop seed industry innovation system is large but weak, the seed industry innovation efficiency is low, and the innovation ecology of the innovation chain and the industrial chain integration is immature, which seriously restrict the high-quality development of China’s seed industry. Based on analyzing the development trend of the global crop seed industry and identifying the problems and obstacles restricting the integration of China’s seed industry innovation chain and industrial chain, it is suggested to fully consider the unique laws and needs of agricultural seed industry innovation, strengthen top-level design, optimize and integrate the national seed industry scientific and technological forces, and build a market-oriented, enterprise-centered, industry-university#2;research-government integration, and whole industry chain integration. The seed industry innovation system with Chinese characteristics fully utilizes the advantages of a unified large national market on the basis of fully considering regional differences, so as to promote the integration of the innovation chain and the industrial chain.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-12-13 Cooperative journals: 《计算机应用研究》
Abstract： Aiming at the problems of low system throughput rate and low system identification rate of traditional dynamic frame time gap Aloha multi-label collision prevention algorithm (DFSA) , this paper proposes an UHF RFID collision prevention algorithm (OVSF-DFSA) which can be identified in parallel. By combining the code division multiple access technology based on orthogonal variable spread spectrum factor (OVSF) code as spread spectrum code and dynamic frame time slot ALOHA (DFSA) protocol, the algorithm breaks the limitation of recognizing only one tag in a single time slot and realizes the transformation from label collision to code collision. Based on theoretical analysis and simulation experiment, this paper explores the performance of the system throughput rate, total time slot number and system recognition rate under the algorithm. Experimental results show that when the frame length of fs>2 and OVSF code length m>2, and the tag number is greater than 200, the system throughput rate under OVSF-DFSA algorithm is m times that of DFSA algorithm, and compared with DFSA, MS-DFSA and PIGDFSA algorithm, OVSF-DFSA algorithm has better performance in the above performance.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-01-02 Cooperative journals: 《工程热物理学报》
Abstract：大气中水蒸气会影响气溶胶颗粒的生长演化动力学特性,从而改变其环境效应。当前，对包含有机组分气溶胶颗粒与水相互作用机理的认识还很局限。本文建立了纯有机气溶胶和有机-无机混合气溶胶颗粒水溶特性研究分子动力学模型，分别模拟了不同温度条件下不同卤化钠盐(NaI/NaCl/NaF)对丙二酸(C3H4O4)团簇水溶特性的影响情况。重点分析了各影响因素作用下团簇结构和气粒界面特性。结果表明，温度升高，C3H4O4-H2O 团簇相继出现分层结构和混合结构。加入40 个卤化钠分子后，水分子对初始团簇溶解程度的排序为40 NaF < 40 NaCl < 0 NaX < 40 NaI，且差异随着温度的升高而变大。高温(T=300K)时，各种团簇的表面均包含C3H4O4分子和H2O 分子，且C3H4O4分子的疏水基朝向气相一侧。
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-21 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the interaction of polymorphisms of PPAR-γ2 gene -C34G and NADPH oxidase subunit p22phox gene -C242T with helicobacter pylori (H. pylori) infection in esophageal squamous cell carcinoma (ESCC) . Methods A total of 200 cases of LSCC of Broder grade I, 200 of Broder grade II and of grade III were enrolled in this study with 200 healthy individuals as the control group. The genetic polymorphisms of PPAR-γ2 gene -C34G and NADPH oxidase subunit p22phox gene -C242T were analyzed using PCR-RFLP in peripheral blood leukocytes. 14 C-urea breath test ( 14 C-UBT) was used to test 14 C disntegration per minute (DPM) for evaluating the infection status of H. pylori. An unconditional logistic regression model was used to analyze the interaction of nucleotide polymorphisms and H. pylori infection. Results The risk of ESCC significantly increased in subjects with -C34G (CG), -C34G(GG), -C242T (CT), and -C242T (TT) genotypes. Combined analysis of the polymorphisms showed that the subjects carrying -C34G (GG)/ -C242T (TT) had a high risk of ESCC, and a positive interaction was found between -C34G (GG) and -C242T (TT) in increasing the risk of ESCC. Positive interactions in the pathogenesis of ESCC were also found between -C34G (CG) and -C242T (TT), between -C34G (CG) and -C242T (CT), and between -C34G (GG) and -C242T (CT) (γ>1). The risk of ESCC significantly increased in subjects with H. pylori infection, which showed positive interactions with -C34G (CG), -C34G (GG), -C242T (CT) and -C242T (TT) in increasing the risk of ESCC (γ>1). Conclusion Individuals carrying -C34G(CG), -C34G(GG), -C242T (CT) and -C242T (TT) genotypes have a high risk of developing ESCC, and these genotypes interact with H. pylori infection in the pathogenesis of LSCC, suggesting the importance of eradicating H. pylori for prevention of ESCC.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Basic Disciplines of Agriculture submitted time 2017-11-08 Cooperative journals: 《中国生态农业学报》
Abstract：地表温度是影响陆-气之间能量和物质交换的重要地球物理变量, 对调节全球气候系统能量循环起着不可或缺的作用。为探讨美国国家大气研究中心(The National Center for Atmospheric Research, NCAR)公共陆面模式(Community Land Model, CLM)对地表温度的模拟能力, 利用1948—2004 年美国国家环境预报中心(National Centers for Environmental Prediction, NCEP)大气强迫场和NCAR 陆面模式CLM3.0、CLM3.5、CLM4.0和CLM4.5 对内蒙古地区1981—2004 年的地表温度进行off-line 模拟, 并与观测地面温度资料进行对比。结果表明: NCAR/CLM 系列陆面模式模拟地表温度都能较好地再现内蒙古地表温度的时空变化特征, 与台站观测有着较好的一致性, 其中CLM4.5 在内蒙古地区模拟能力最好, 与观测的相关系数最高、平均偏差和均方根误差都最小, 这主要得益于CLM4.5 对粗糙度计算的改进; 不同版本CLM 模拟地表温度普遍较观测数值偏低,在冬季各版本CLM 模拟结果与观测值之间的平均偏差达到最小, 在夏季的偏差增大, 尤其是在东部地区, 夏季偏差3 ℃以上, 说明对最高地表温度的模拟能力东部和中部地区明显低于西部地区; 西部地区各个版本差别并不如东部和中部地区明显, 这与CLM4.0 和CLM4.5 改进了雪模式和水文过程有关。综上, CLM4.0 和CLM4.5 在内蒙古地区有较好的适用性, 且模拟值均低于实测地表温度, 冬季偏差较小, 夏季偏差增大, 东部地区偏差大于中部和西部地区。
Subjects: Dynamic and Electric Engineering >> Engineering Thermophysics submitted time 2017-11-07 Cooperative journals: 《工程热物理学报》
Abstract：大气中水蒸气会影响气溶胶颗粒的生长演化动力学特性，从而改变其环境效应。当前，对包含有机组分气溶胶颗粒与水相互作用机理的认识还很局限。本文建立了纯有机气溶胶和有机一无机混合气溶胶颗粒水溶特性研究分子动力学模型，分别模拟了不同温度条件下不同卤化钠盐(Na工/NaCl/NaF)对丙二酸(C3H40户团簇水溶特性的影响情况。重点分析了各影响因素作用下团簇结构和气粒界面特性。结果表明，温度升高，C3H404 H}O团簇相继出现分层结构和混合结构。加入40个卤化钠分子后，水分子对初始团簇溶解程度的排序为40NaF<40NaCl
Subjects: Astronomy >> Astrophysical processes submitted time 2017-10-20 Cooperative journals: 《天文研究与技术》
Abstract：天体视位置是进行天文定姿的必备数据，目前视位置计算的研究多基于地面和海上，天基平台的发展需进一步研究。介绍了星上视位置转换原理，推导各种位置改正公式，基于新天文参考框架建立一种太阳系内天体视位置计算模型，可计算任意时刻天体的地心视位置和站心视位置。与天文年历地心视位置相比，类木行星的赤经差值在10 ms以内，赤纬差值在220 mas以内;与STK仿真的站心视位置相比，赤经差值在0.15s以内，赤纬差值在2"以内。实验表明，该模型可以正确计算测瞬太阳系内天体的视位置，其精度满足天文定姿的需求。
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2017-09-20
Abstract：光学纯脂肪族羟基酸及其衍生物是重要的手性砌块，可以用于制备多种天然产物或生物活性分子。例如，长链γ-, δ-羟基酸通过分子内环化得到的手性内酯，是一种重要的香料分子，在食品和精细化工领域有重要的应用价值。研究表明酮酸或酮酯的不对称还原反应是合成手性羟基酸/羟基酯最高效和最具原子经济性的路径。然而，迄今为止绝大多数研究报道的酶或化学催化剂作用的底物范围局限于α-, β-芳香族酮酯或短链酮酯，除酿酒酵母、毕赤酵母等细胞催化以外，针对长链脂肪族γ-, δ-酮酸/酮酯的酶催化高立体选择性不对称还原反应仍然是一个重大挑战。因此，挖掘和改造对长链脂肪族γ-, δ-酮酸/酮酯具有高活力和高选择性的新酶具有重要的科学和应用价值。 本文本论文首先采用传统方法从土壤中筛选到能够不对称还原4-羰基癸酸的新型催化剂Pseudomonas panipatensis。接着将该野生菌进行全基因组测序，以基因狩猎的方法从该菌中成功克隆出目标酶PpCR（Pseudomonas panipatensis carbonyl reductase），该羰基还原酶的辅酶依赖型为NADPH。然后以PpCR为探针，通过数据库挖掘，筛选到催化性能更优良的羰基还原酶SmCR（Serratiamarcescens carbonyl reductase）。对SmCR的催化性质进行研究，发现其最适反应pH为6.0，最适反应温度为40oC。SmCR在30oC下相对稳定，半衰期为90 h。在40oC和50oC下的半衰期为50 h 和15 h。对于4-羰基癸酸，SmCR的Km值为1.26 mM，kcat为0.128 min-1。 在100 mL 100 mM的pH 6.0磷酸钠缓冲液中进行手性内酯的制备反应，4-羰基癸酸的浓度为2 mM，获得产物(R)-γ-癸内酯的ee值为99%，分离得率为72%。以5-羰基癸酸为底物在相同条件下进行制备，获得ee值为95%的(R)-γ-癸内酯，分离得率为70%。论文结果证明SmCR是首个不对称还原4-羰基癸酸和5-羰基癸酸的还原酶，在(R)-γ-癸内酯和(R)-γ-癸内酯的生产具有潜在的应用价值。
Subjects: Library Science，Information Science >> Library Science submitted time 2023-08-27 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] Identifying the trajectory of development is of great importance to scientific and technological innovations. However, existing methods such as expert interviews and citation analysis cannot meet the current situation of the explosive growth of literature. In response to this problem, this paper proposes a new identification method of filed development trajectory. [Method/process] This method identifies the research topics and related scholars by using Kmeans ++ and spectral clustering algorithms with the keyword-scholar matrix, calculates the correlation between different topics, and finally visualizes the trajectory of developmen. [Result/conclusion] Through the empirical analysis of the field of artificial intelligence, the results show that the method can effectively reflect the evolution of the topic of field research, help researchers quickly locate popular research topics and focuses, and enrich the research methods related to the trajectory of field development.
Subjects: Nursing >> Nursing submitted time 2023-05-12
Abstract： Objective To explore the application effect of BOPPPS combined with dynamic scenarios simulation in ICU nursing teaching. Methods Totally 57 nursing students who practiced their internship in ICU ward of a grade-A hospital from July, 2021 to February, 2022 were selected as the research objects. In the clinical teaching of ICU, 27 students in the control group adopted conventional teaching method, and 30 students in the experimental group adopted BOPPPS combined with dynamic scenarios simulation teaching method. The two groups were compared in terms of assessment results, independent learning ability and critical thinking level. Results The examination results of the test group were better than that of the control group, with a significant difference(P＜0.05). The experimental group had higher evaluation on the teaching effect of BOPPPS combined with dynamic scenario simulation. After teaching, the planning and implementation, self-management and total score of independent learning ability in the experimental group were significantly higher than those of the control group, with statistical significance (P＜0.05). There was statistically significant difference in the total score of critical thinking in experimental group before and after teaching (P＜0.05). Conclusion BOPPPS combined with dynamic scenarios simulation can improve students'' independent learning ability, cultivate students'' critical thinking, and achieve good teaching effect.
Peer Review Status:Awaiting Review
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： none
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-07-09 Cooperative journals: 《计算机应用研究》
Abstract： The performance of the V2V communication system depends on the characteristics of the wireless channel, so it is very important to use a suitable model to characterize the communication channel. This paper studied the vehicular communication channel in the 3D street scattering environment. Considering the scatterers such as tall buildings and trees on both sides of the road, and the transmitting and receiving ends are moving, use multi-antenna technology to establish the elliptic column scattering model. Using geometric analysis, this paper duduced the time auto-correlation function (ACF) and cross-correlation function (CCF) ; compare the difference of ACF and CCF in the case of line-of-sight(LOS) and non-line-of-sight (NLOS) , this paper verified the feasibility of the simulation method; study the difference in channel capacity under different antenna arrays and scattering environments, which highlight 3D models more accurately. The consistency between the measurements results and the theoretical analysis shows the usability of this 3D model and broadens the research of vehicular communication systems.
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