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Spatial location differentiation and development decision optimization of characteristic villages and towns in China

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Geography and Sustainability 2022年第1期3卷 21-31页

作者： Jintao Li Yuling Gong Institute of Governance Shandong UniversityQingdao 266200China School of Politics and Public Administration Shandong UniversityQingdao 266200China Centre for Quality of Life and Public Policy Research Shandong UniversityQingdao 266237China School of Environmental Science and Engineering Shandong UniversityQingdao 266200China Institute of Eco-Environmental Forensics Shandong UniversityQingdao 266200China

Due to rapid urbanization and industrialization,the gap between urban and rural development has gradually *** development problems have been a significant topic of discussion,and are related to people’s *** article built a point-axis-region location driving system to analyze the spatial location differentiation of characteristic villages and towns(CVTS)using the kernel density model,and explored the mechanism of location driving factors with a geographical detector *** results show that vegetables and fruits are the main types of products in *** account for 27.60%and 34.68%of all types of products,and occur mainly in the east and central regions of ***,all point-axis-region driving factors have a significant influence on grain *** mean values of driving forces of vegetables and fruits are larger than other types of CVTS,and their values are 0.12 and *** average driving forces on all CVTS in the northeast are higher than those in other regions,especially the driving forces of vegetables and medicinal crops(0.24 and 0.18,respectively).Finally,we proposed that the Chinese government should employ engineering technology,invest on road networks,e-commerce and blockchain technology to optimize the point-axis-region location advantages,to promote the sustainable development of *** detection of driving mechanisms on spatial location differentiation of CVTS has important research value for location theory and rural region systems research.

关键词： Characteristic villages and towns Point-axis-region driving system Spatial driving factors Decision optimization Kernel density

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Paradigm shift and prospects of China's earthquake emergency management policies:Analysis of historical institutionalism

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Emergency Management Science and Technology 2022年第1期2卷 120-132页

作者： Xiangjie Cui School of Political Science and Public Administration Shandong UniversityQingdao 266200China Center for Quality-of-Life and Public Policy Studies Shandong UniversityQingdao 266200China

China's earthquake emergency management policies have experienced a total of four types of paradigms:the paradigm focusing on disaster relief from 1949−1966,the paradigm focusing on earthquake prevention from 1966−1989,the paradigm focusing on earthquake mitigation from 1989−2016,and the paradigm integrating disaster prevention,mitigation,and relief from 2016 to *** dependence can be found in China’s earthquake emergency management policies,which have accumulated to implement comprehensive disaster mitigation based on a pure focus on disaster *** addition,earthquake emergency management policies also have a change logic in which subjects are increasingly diversified,policy tools are continuously developed and influenced by the economic system,and policy paradigm changes are influenced by the international environment,national strategies,and *** the future,earthquake emergency management policies should start from organizational change,digital change and rule of law construction to promote the modernization of China's earthquake emergency governance system and capacity.

关键词： earthquake disaster prevention

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Guided wave propagation analysis in stiffened panel using time-domain spectral finite element method

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Chinese Journal of Aeronautics 2022年第10期35卷 208-221页

作者： Zexing YU Chao XU Jiaying SUN Fei DU School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China Qingdao R&D Institute Northwestern Polytechnical UniversityQingdao 266200China

Stiffened panels have been widely utilized in fuselages and wings as critical load-bearing components. These structures are prone to be damaged under long-term and extreme loads, and their health monitoring has been a common concern. The guided wave-based monitoring method is regarded as an efficient approach to detect the damage in stiffened plates because of its wide monitoring range and high sensitivity to micro-damage. Efficient simulation of wave propagation can theoretically demonstrate the detection mechanism of the method. In this study, a Time-Domain Spectral Finite Element Method(TD-SFEM) is adopted to study the wavefield in stiffened plates,where continuous Absorbing Layers with Increasing Damping(ALID) strategy is proposed to circumvent the disturbance of reflected waves on boundaries. After the convergence analysis, the developed TD-SFEM with ALID is validated by the finite element method first. Then, wave scattering and the influence of the stiffener are investigated in detail by comparing the results with the non-stiffened structure. Finally, the effects of the parameters of the stiffener, such as the height and width, on wave propagation are studied, respectively. The results illustrate that the proposed TDSFEM with ALID is an efficient approach to study the wave propagation in the stiffened plate and can reveal the mechanism of influence of the stiffener. It is found that the height of the stiffener changes the interference of wavefield in the plate, while the effects of the width are mainly in wave scattering and mode conversion.

关键词： Absorbing layers with increasing damping Guided waves Stiffened Panel Time-domain spectral finite element Wave propagation

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ELM-Based Impact Analysis of Meteorological Parameters on the Radio Transmission of X-Band over the Qiongzhou Strait of China

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China Communications 2023年第12期20卷 244-256页

作者： Cheng Yang Yafei Shi Jian Wang Jianguo Ma School of Microelectronics Tianjin UniversityTianjin 300072China Qingdao Institute for Ocean Technology Tianjin UniversityQingdao 266200China Shandong Engineering Technology Research Center of Ocean Information Awareness and Transmission Qingdao 266200China School of Micro-and Nano-Electronics Zhejiang UniversityHangzhou 310058China

Communication in the evaporation duct layer is greatly affected by the variation of meteorological *** on the experimental result of the radio transmission of the X-band over the Qiongzhou Strait of China,the characteristic of the duct and its influence on the transmission effect is *** results indicate that the evaporation duct height(EDH)has a negative Spearman’s rank correlation of-0.90 with the relative humidity and a positive correlation coefficient of 0.84 with the wind *** on the Extreme Learning Machine(ELM)network,we proposed a Met-ELM model that can provide efficient support in predicting propagation characteristics at *** predicted results of the MetELM model are consistent with the measurements;the root-mean-square-error is 1.66 dB,with the correlation coefficient reaching 0.96,while the proportion of mean absolute error less than 2 dB has reached81.41%.The data-derived Met-ELM model shows great accuracy in predicting propagation characteristics at nighttime,which also meets the acceptable requirements for radio wave propagation.

关键词： evaporation duct neural network prediction model propagation characteristic

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黄河三角洲盐碱土根际微环境的微生物多样性及理化性质分析

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环境科学 2020年第3期41卷 1449-1455页

作者：赵娇谢慧君张建山东大学环境科学与工程学院青岛266200 山东大学环境研究院青岛266200

土壤盐碱化是限制全世界农业发展的主要问题.在盐碱土壤上种植盐生植物和耐盐植物可以对盐碱土壤进行脱盐,而盐碱土壤中的微生物对盐生植物和耐盐植物的生长起着重要作用.本研究在盐碱地上选取玉米、棉花、盐地芦苇和盐地碱蓬这4种有代... 详细信息

土壤盐碱化是限制全世界农业发展的主要问题.在盐碱土壤上种植盐生植物和耐盐植物可以对盐碱土壤进行脱盐,而盐碱土壤中的微生物对盐生植物和耐盐植物的生长起着重要作用.本研究在盐碱地上选取玉米、棉花、盐地芦苇和盐地碱蓬这4种有代表性的植物,采集土壤样品,探究植物根系与非根系主要细菌群落与土壤理化性质和盐碱土壤微生物多样性的关系.结果表明,盐地碱蓬的根系微生物在一定程度上影响了土壤的pH,土壤中的盐度与土壤营养物质呈明显的负相关关系.所有土壤样品中相对丰度较高的前5个细菌门均为变形菌门、放线菌门、拟杆菌门、绿弯菌门和酸杆菌门.其中,棉花、芦苇和盐地碱蓬中根系土壤与非根系土壤耐盐菌门存在较大差异,分析高通量测序结果可以得出3种植物根系与非根系土壤中差异较大的耐盐细菌属,如棉花土壤中差异较大的Actinophytocola和Lechevalieria,芦苇土壤中差异较大的Bacillus和Filobacillus,以及盐地碱蓬土壤中的Echinicola.本研究可为盐碱地中接种促进植物生长的微生物提供理论依据.

关键词：盐碱地土壤耐盐植物根际微环境土壤理化性质土壤微生物多样性

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Collecting and analyzing key-value data under shuffled differential privacy

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Frontiers of Computer Science 2023年第2期17卷 241-243页

作者： Ning WANG Wei ZHENG Zhigang WANG Zhiqiang WEI Yu GU Peng TANG Ge YU Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China School of Computer Science and Engineering Northeastern UniversityShenyang 110819China Key Lab of Cryptologic Technology and Information Security Ministry of EducationShandong UniversityQingdao 266200China School of Cyber Science and Technology Shandong UniversityQingdao 266200China

1 Introduction Key-value data,as NoSQL data widely used in recent years,has been frequently collected and used for analysis in major websites and mobile *** frequency distribution estimation on the key domain,as well as the mean estimation of values associated with the same key,are crucial and worth billion dollars in the ***,in real applications,the key-value records are submitted by terminal devices of different *** collecting the information from users may pose serious risks on personal *** the other hand,the emerging shuffled differential privacy(SDP)model[1]is proposed to collect sensitive data from users.

关键词： NoSQL app value

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Public-private-core maintenance in public-private-graphs

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Intelligent and Converged Networks 2021年第4期2卷 306-319页

作者： Dongxiao Yu Xilian Zhang Qi Luo Lifang Zhang Zhenzhen Xie and Zhipeng Cai School of Computer Science and Technology Shandong UniversityQingdao 266200China Department of Computer Science Georgia State UniversityAtlantaGA 30080USA

A public-private-graph(pp-graph)is developed to model social networks with hidden relationships,and it consists of one public graph in which edges are visible to all users,and multiple private graphs in which edges are only visible to its endpoint *** contrast with conventional graphs where the edges can be visible to all users,it lacks accurate indexes to evaluate the importance of a vertex in a *** this paper,we first propose a novel concept,public-private-core(pp-core)number based on the k-core number,which integrally considers both the public graph and private graphs of vertices,to measure how critical a user *** then give an efficient algorithm for the pp-core number computation,which takes only linear time and *** that the graphs can be always evolving over time,we also present effective algorithms for pp-core maintenance after the graph changes,avoiding redundant re-computation of pp-core *** experiments conducted on real-world social networks show that our algorithms achieve good efficiency and *** to recalculating the pp-core numbers of all vertices,our maintenance algorithms can reduce the computation time by about 6-8 orders of magnitude.

关键词： core decomposition maintenance public-private-graph(pp-graph) critical user social network

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Properties and Anti-Ultraviolet Activity of Gallic Acid-Chitosan-Gelatin Mixed Gel

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Journal of Ocean University of China 2022年第1期21卷 204-212页

作者： WANG Wenjie XUE Changhu MAO Xiangzhao College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266200China

Hydrogel has high water content and structural similarity with natural extracellular *** it has been widely studied and applied in the field of *** order to further develop multifunctional hydrogels,we prepared mixed gels with antiultraviolet *** study found that the addition of polysaccharides and polyphenols was beneficial to the rheological,me-chanical properties,and biological activity of the ***(CS)could significantly improve the viscoelasticity,hardness,gel strength,thermal stability and crystallinity of ***,the addition of gallic acid(GA)could not only provide significant cross-linking effect,improve gel properties and microstructure,but also improve the UV resistance of the mixed gel.

关键词： gallic acid chitosan gelatin gel properties UV resistance

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The Electromagnetic Compatibility between FAST and Public Mobile Communication Stations and its Cognitive Using Frequency Strategy

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Research in Astronomy and Astrophysics 2022年第12期22卷 183-197页

作者： Jian Wang Yi-Bo Zhao Ya-Fei Shi Cheng Yang Yu-Long Hao Jian-Min Sun School of Microelectronics Tianjin UniversityTianjin 300072China Qingdao Institute for Ocean Technology Tianjin UniversityQingdao 266200China Guizhou Radio Monitoring Station Guiyang 550005China

To master the electromagnetic environment characteristics around the Five-hundred-meter Aperture Spherical radio Telescope(FAST)and ensure a better ecological environment in the radio-quiet zone of FAST,we analyzed the radiation characteristics of the public communication stations around *** comparing the FAST received signal power from the communication stations and the interference protection threshold of the radio astronomy applications,we found that the total proportion of the communication stations exceeding the radio astronomy protection threshold is 69.01%.Furthermore,to fully protect the regular operation of FAST,we proposed four interference avoidance and frequency coordination strategies based on the cognitive ***:(1)increasing the operating frequency of the communication station;(2)adjusting the direction of the transmitter antennas;(3)reducing the height of the transmitter antennas;(4)decreasing the transmitting power of the communication *** a result,the impact on FAST can effectively be reduced,and the FAST's received power from the communication stations will be lower than the radio astronomy protection threshold by using the above mentioned four *** the analysis of the experiment,the prediction is consistent with the overall trend of the measurement,and using frequency strategies can significantly reduce the signal power at the receiving ***,we construct a quality evaluation system for frequency coordination and analyze the satisfaction of the four strategies under the four *** results show that adjusting the direction of the transmitter antennas has better satisfaction,and the maximum satisfaction is *** above research results can be further expanded to potentially improve the electromagnetic ecological environment around FAST and support the regular operation of FAST.

关键词： methods:analytical methods:statistical telescopes

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A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong Luo Yunsheng Zhao Ke Xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and *** assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety *** study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety *** methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk ***,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision *** in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety *** findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

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