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基于智能合约的农业供应链溯源技术研究

电子技术应用 2024年第5期50卷 53-57页

作者：刘卫春黄海郑军红浙江理工大学计算机学院浙江杭州310000

食品安全和污染风险相关的问题越来越多,迫切需要高效的追溯解决方案。通过溯源可以高效追溯食品的源头,并且进行追责,从而提高食品安全。为此设计了一个基于以太坊智能合约的农业供应链溯源机制,该机制通过引入NFT技术,优化了区块链农... 详细信息

食品安全和污染风险相关的问题越来越多,迫切需要高效的追溯解决方案。通过溯源可以高效追溯食品的源头,并且进行追责,从而提高食品安全。为此设计了一个基于以太坊智能合约的农业供应链溯源机制,该机制通过引入NFT技术,优化了区块链农产品溯源过程。实验结果表明,所提出的供应链框架在成本效益、溯源效率方面优于现有的区块链溯源基准技术。

关键词：智能合约农业供应链溯源技术区块链

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水声材料声学参数测试技术的进展

中国材料进展 2024年第1期43卷 79-88页

作者：曹锃佟昊阳易燕颜士玲黄唯纯李水陈毅赵涵杭州应用声学研究所国防水声计量一级站浙江杭州311400 南京大学固体微结构物理国家重点实验室现代工程与应用科学学院江苏南京210093

水声材料是水下声系统能力形成和发展的基础,其声学参数测试技术是确保水声材料构件功能实现的重要保障,然而目前水声材料构件的测试技术面临着低频拓展及高压拓展等方面带来的技术挑战。水声材料构件的声管测试技术可分为驻波管法、脉... 详细信息

水声材料是水下声系统能力形成和发展的基础,其声学参数测试技术是确保水声材料构件功能实现的重要保障,然而目前水声材料构件的测试技术面临着低频拓展及高压拓展等方面带来的技术挑战。水声材料构件的声管测试技术可分为驻波管法、脉冲管法和行波管法,此3种方法在适用性方面相互补充,但存在测试构件尺寸小难以阐明结构的整体特性、构件与管壁间的缝隙造成测量失准的问题。自由场测试技术及压力罐测试技术是大面积水声材料测试的有效手段,但存在测试构件边缘衍射造成测量准确性降低的问题。对目前采用的水声材料测试技术及其研究现状进行了综述,讨论了各类测试技术存在的困难和挑战,并展望了水声材料构件测试技术未来的发展方向。

关键词：水声材料声管自由场压力罐低频高压边缘衍射

安徽省自然资源调查监测数据综合评价指标体系构建研究

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测绘与空间地理信息 2024年第9期47卷 28-32页

作者：孔丽马卫春曲丽佳安徽省基础测绘信息中心安徽合肥230031

针对安徽省耕地、林地、草地、湿地、水等自然资源特性,紧紧围绕守住安全底线、提高利用效率、保护生态功能、改善生活品质、降低环境影响、提升治理水平等6个主题,基于“压力—状态—影响—响应”的业务逻辑,选择41个指标构建了一套清... 详细信息

针对安徽省耕地、林地、草地、湿地、水等自然资源特性,紧紧围绕守住安全底线、提高利用效率、保护生态功能、改善生活品质、降低环境影响、提升治理水平等6个主题,基于“压力—状态—影响—响应”的业务逻辑,选择41个指标构建了一套清晰明确的综合评价指标体系,并选取六安市为试点区域进行验证。评价结果与六安市各县区实际生态经济发展相对状况相符,对开展省级自然资源调查监测数据的评价工作具有参考价值。

关键词：自然资源 PSIR模型综合评价指标体系

Research on the Variation of Population Distribution and Its Characteristics Based on Spatial Autocorrelation Method: A Case Study of Poyang Lake Region in Jiangxi Province

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 76-78页

作者： Luo Hui Yang weichun School of Medicine Jinggangshan UniversityJi＇an Jiangxi 343009China Shandong Normal University Jinan Shandong 250014China

According to Statistical Yearbook of Jiangxi Province(2.01～2.06),We analyze the time-space variation of population distribution of Poyang Lake region from the two points of *** former is quality of population,which involves culture structure,occupational structure,age structure and sex structure of *** latter is quantity of population,which only involves the amount of ***,we can reveal the internal relations and action mechanism of variation of population distribution by analyzing the regional economic development,population urbanization,land use and ecological landscape of Poyang Lake *** is important to provide help for region planning,ecological landscape planning and environmental protection by correct understanding the man-land relationship of natural-human ecosystem in Poyang Lake region.

关键词： population distribution spatial autocorrelation changing characteristics Poyang Lake region

黄河下游地区基本公共服务投入效率时空分异及影响因素

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南阳师范学院学报 2024年第5期23卷 9-18页

作者：程启先陈飞燕何伟纯牛继强信阳师范大学地理科学学院河南信阳464000 信阳师范大学河南省微波遥感及资源环境监测工程研究中心河南信阳464000

基本公共服务投入效率对基本公共服务均等化及协调发展具有重要作用。本研究以黄河流域下游地区为案例区域,运用非期望产出超效率SBM模型、标准差椭圆模型、梯度提升树回归模型以及灰色GM(1,1)模型对基本公共服务投入效率的时空分异及... 详细信息

基本公共服务投入效率对基本公共服务均等化及协调发展具有重要作用。本研究以黄河流域下游地区为案例区域,运用非期望产出超效率SBM模型、标准差椭圆模型、梯度提升树回归模型以及灰色GM(1,1)模型对基本公共服务投入效率的时空分异及其影响因素进行实证研究。结果表明:基本公共服务投入效率呈现出“东北—西南”格局,重心向东北偏移,其中山东段的评价值增长,而河南段下降;人口规模、产业经济和资源消耗是影响基本公共服务投入效率的主导要素,预测模型结果表明在未来时段多数地市的变化趋势比较平稳。

关键词：基本公共服务非期望产出超效率SBM模型投入效率黄河下游地区

Flow Boiling of Ammonia in a Diamond-Made MicroChannel Heat Sink for High Heat Flux Hotspots

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Journal of Thermal Science 2020年第5期29卷 1333-1344页

作者： YANG Qi MIAO Jianyin ZHAO Jingquan HUANG Yanpei FU weichun SHEN Xiaobin School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Space Thermal Control Technology Beijing Institute of Spacecraft System EngineeringChina Academy of Space TechnologyBeijing 100094China

To solve the heat dissipation problem of electronic devices with high heat flux hotspots,a diamond microchannel heat sink consisting of 37 parallel triangular microchannels with channel lengths of 45 mm and hydraulic diameters of 2.0|im was *** flow boiling heat transfer characteristics of ammonia in the microchannels were investigated under high heat fluxes of 473.9-1000.4 W/cm^*** flow boiling experiments with saturation temperatures of 2.℃,30℃,and 35℃ and mass fluxes of 98-12.0 kg/m^2. were conducted,as well as subcooled flow boiling with inlet subcooling of 5℃ as a *** temperature and pressure drop measurements were *** main conclusions below can be drawn.(1)At a given heat flux,the heat source temperature first decreased and then increased with the mass flux,and there existed an optimum mass flux to optimize the cooling performance of the heat sink.(2.The heat transfer performance under the saturated inlet condition was obviously better than that under the subcooled inlet condition.(3)A larger saturation temperature leaded to weakening of both the heat transfer capacity and the stability of the microchannel heat ***,with the high heat diffusion ability of the diamond substrate and the great heat transfer capacity of ammonia flow boiling in microchannels,the heat sink can achieve a heat removal capacity of up to 1000.4 W/cm^2.

关键词： high heat flux flow boiling microchannel ammonia multipoint heat sources

A new species of Spherillo Dana from China(Isopoda: Oniscidea)

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Zoological Systematics 2018年第1期43卷 118-122页

作者： weichun Li College of Agronomy Jiangxi Agricultural University

Spherillo hailuogouensis *** described from Hailuogou National Glaciers Forest Park,*** new species can be diagnosed by the apical part of the male pleopod endopod 1 bearing four spinules near middle and four well-developed denticles on outer *** specimens are deposited in the Insect Museum,Jiangxi Agricultural University,Nanchang,***.

关键词： Isopoda Oniscidea Spherillo new species China

Water-saving Technologies,Solar Green House and Ecological Rehabilitation in Minqin Oasis of Gansu Province,China

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Chinese Journal of Population,Resources and Environment 2008年第3期6卷 73-82页

作者： Tao weichun Shi Minjun Zhao Xuetao Graduate University of Chinese Academy of Sciences CAS Beijing 100049 China Research Center on Fictitious Economy and Data Science CAS Beijing 100080 China

Land degradation and desertification have become severe environmental problems in arid areas due to excessive use of water resources. It is urgent to reduce agricultural water use for ecological rehabilitation, which may result in a decrease in agricultural production and farmer＇s welfare. This paper focused on the impacts of some main measures including extensions of watersaving irrigation, expanding solar green house and increasing off-farm employment, which are generally recognized to be important to alleviate water shortage and poverty. A bioconomic model is applied taking Minqin Oasis in Gansu Province as a case study site. Simulation results showed that the effect of expanding solar greenhouse was more positive than other ones so it drew more attention. On the view of the different effects between each irrigation zone, mixed policy patterns suitable for them are suggested. In Baqu, expanding solar greenhouse should be the most important, auxiliary with encouraging pipe irrigation. Inversely, with regard to Quanshan, the major attention should be paid to subsidy for pipe irrigation and it would be better to supply the off-farm employment opportunities to the households in Huqu, where the expanding of solar greenhouse should also be summoned. Finally, it should be noted that farmer＇s income would only resume to 90% of the current level in the short run by putting more effort into local policies. Thus, the ecological compensation is needed to ensure farmer＇s welfare.

关键词： water-saving technologies solar green house Minqin Oasis ecological rehabilitation

Enhancing the mechanical properties and cytocompatibility of magnesium potassium phosphate cement by incorporating oxygen-carboxymethyl chitosan

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Regenerative Biomaterials 2021年第1期8卷 92-101页

作者： Changtian Gong Shuo Fang Kezhou Xia Jingteng Chen Liangyu Guo weichun Guo Department of Orthopedics Renmin Hospital of Wuhan UniversitWuhan 430060China

Incorporating bioactive substances into synthetic bioceramic scaffolds is *** this work,oxygen-carboxymethyl chitosan(0-CMC),a natural biopolymer that is nontoxic,biodegradable and biocompatible,was introduced into magnesium potassium phosphate cement(K-struvite)to enhance its mechanical properties and *** study aimed to develop 0-CMC/magnesium potassium phosphate composite bone cement(OMPC),thereby combining the opti-mum bioactivity of O-CMC with the extraordinary self setting properties and mechanical intensity of the *** results indicated that O-CMC incorporation increased the compressive strength and setting time of K-struvite and decreased its porosity and pH ***,OMPC scaffolds remarkably improved the proliferation,adhesion and osteogenesis related differ-entiation of MC3T3-E1 ***,O-CMC introduced suitable physicochemical properties to K-struvite and enhanced its cytocompatibility for use in bone regeneration.

关键词： magnesium phosphate cement oxygen-carboxymethyl chitos an physic ochemic al properties cytocompatility