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Promoting grain production through high-standard farmland construction:Evidence in China
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China
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作者 Jie Xue Xianglin Zhang +3 位作者 Songchao Chen Bifeng Hu Nan Wang Zhou Shi 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期283-297,共15页
Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of researc... Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified framework.Thus,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification agreement.The validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,respectively.The FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,respectively.High consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,China.In contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern China.Field size was the most important factor for mapping cropland.For area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and GlobCover2009.The cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four products.Our results can provide valuable suggestions for selecting cropland products at the national or provincial scale and help cropland mapping and reconstruction,which is essential for food security and crop management,so they can also contribute to achieving the Sustainable Development Goals issued by the United Nations. 展开更多
关键词 global LULC products cropland mapping accuracy evaluation food security China
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Smart Farming for Sustainable Rice Production:An Insight into Application,Challenge,and Future Prospect
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作者 Norhashila HASHIM Maimunah Mohd ALI +4 位作者 Muhammad Razif MAHADI Ahmad Fikri ABDULLAH Aimrun WAYAYOK Muhamad Saufi Mohd KASSIM Askiah JAMALUDDIN 《Rice science》 SCIE CSCD 2024年第1期47-61,共15页
Rice has a huge impact on socio-economic growth,and ensuring its sustainability and optimal utilization is vital.This review provides an insight into the role of smart farming in enhancing rice productivity.The applic... Rice has a huge impact on socio-economic growth,and ensuring its sustainability and optimal utilization is vital.This review provides an insight into the role of smart farming in enhancing rice productivity.The applications of smart farming in rice production including yield estimation,smart irrigation systems,monitoring disease and growth,and predicting rice quality and classifications are highlighted.The challenges of smart farming in sustainable rice production to enhance the understanding of researchers,policymakers,and stakeholders are discussed.Numerous efforts have been exerted to combat the issues in rice production in order to promote rice sector development.The effective implementation of smart farming in rice production has been facilitated by various technical advancements,particularly the integration of the Internet of Things and artificial intelligence.The future prospects of smart farming in transforming existing rice production practices are also elucidated.Through the utilization of smart farming,the rice industry can attain sustainable and resilient production systems that could mitigate environmental impact and safeguard food security.Thus,the rice industry holds a bright future in transforming current rice production practices into a new outlook in rice smart farming development. 展开更多
关键词 rice production smart farming food security agriculture sustainability
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Air pollution, food production and food security: A review from the perspective of food system 被引量:5
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作者 Feifei Sun DAI Yun Xiaohua Yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第12期2945-2962,共18页
Air pollution negatively impacts food security. This paper reviews the current literature on the relationship between air pollution and food security from the perspective of food system. It highlights that agricultura... Air pollution negatively impacts food security. This paper reviews the current literature on the relationship between air pollution and food security from the perspective of food system. It highlights that agricultural emissions which substantially contribute to air pollution could happen at every stage along the food supply chain. Meanwhile, air pollution can not only affect plant growth and animal health but also shift market equilibrium of both agro-inputs and outputs in the food supply chain and thereby affect food security indirectly. Furthermore, this study evaluates the effects of agricultural policy and energy policy on food security and air pollution, respectively, and provides an overview of potential policy instruments to reduce air pollution while ensuring food security. Finally, we identify the remaining research and policy issues for further studies, mainly focusing on the study of household's bounded rational behaviors and the issue of rural aging population. 展开更多
关键词 Air pollution food production and food security A review from the perspective of food system
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Fruit Production Distribution and Adjustment Strategies under the Constraint of Grain Security
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作者 Bingbing MEI 《Asian Agricultural Research》 2016年第4期82-86,共5页
Grain security is the foundation of national security,and guaranteeing the grain security by every possible means is a development priority for the whole country.Rapid development of the fruit industry satisfies incre... Grain security is the foundation of national security,and guaranteeing the grain security by every possible means is a development priority for the whole country.Rapid development of the fruit industry satisfies increasing demands of people for fruits,but also presents certain competition for grain production.From the perspective of limited resources and comparative income,this paper analyzed potential threats of fruit production distribution to grain production in farmland and labor resources,and came up with pertinent adjustment strategies. 展开更多
关键词 GRAIN security FRUIT production DISTRIBUTION Adjustment STRATEGIES
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The Anti-Piracy Measure Using Encryption of Embedded Products May Mitigate the Security Strength
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作者 Zhilong Xiong Rui Zhang +1 位作者 Xin Zhan Zhenglin Liu 《Communications and Network》 2013年第3期430-433,共4页
In this paper, firstly we describe the piracy problem of embedded products. Then we formulate the security features of anti-piracy embedded products. Finally we prove that the anti-piracy measure using encryption of e... In this paper, firstly we describe the piracy problem of embedded products. Then we formulate the security features of anti-piracy embedded products. Finally we prove that the anti-piracy measure using encryption of embedded products may mitigate the security strength. 展开更多
关键词 EMBEDDED productS ANTI-PIRACY ENCRYPTION security STRENGTH Copyright
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CORN PRODUCTION: IMPORTANT WAY TO SECURITY IN GRAIN AND FORAGE
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作者 Ren Tianzhi Li Yingzhong(Institute of Natural Resources & Regional Planning, Chinese Academy of Agricultural Sciences)Director of Institute of Natural Resources & Regional Plan-ning,Chinese Academy of Agricultural Sciences. 《Bulletin of the Chinese Academy of Sciences》 1996年第4期353-355,共3页
The issue of grain supply, once again, has aroused the attention of Chinese and foreigners, since last year’s price rises in the main agricultural products. Although most people believe that China can feed herself in... The issue of grain supply, once again, has aroused the attention of Chinese and foreigners, since last year’s price rises in the main agricultural products. Although most people believe that China can feed herself in the next 20-30 years, it is not an easy task. With such difficulties as increasing population, decreasing arable lands, insufficient water supply, declining grain sown-areas, limited agricultural input and low production enthusiasm, how to resolve the grain issue is becoming a matter that must be settled. 展开更多
关键词 CORN production IMPORTANT WAY TO security IN GRAIN AND FORAGE
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A system-wide approach to minimize the operational cost of bench production in open-cast mining operations 被引量:5
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作者 Burak Ozdemir Mustafa Kumral 《International Journal of Coal Science & Technology》 EI 2019年第1期84-94,共11页
The production cycle of open-cast coal mines generally in eludes drilling, blasting, loading, hauling and coal preparation activities. Individual optimization of these activities does not mean that the whole system is... The production cycle of open-cast coal mines generally in eludes drilling, blasting, loading, hauling and coal preparation activities. Individual optimization of these activities does not mean that the whole system is optimized. This paper proposes a cost model considering all activities in mining cycle and system-wide approach to minimize the total mining cost of bench production. Since the fragmentation size and blast-hole diameter are linked to all activities of mining system, they are considered as decision variables in the problem form ul at io n. The operatio n costs are then minimized by using the evolutionary algorithm. Moreover, the impact of the change in the explosive price, and the hourly unit cost of equipment on total mining cost is quantified by sensitivity analysis. A case study is implemented to demonstrate the developed model. 展开更多
关键词 Mine production cycle Rock FRAGMENTATION - COST optimization EVOLUTIONARY algorithm Sensitivity analysis
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Promoting the Empowerment of Science and Technology to Ensure Food Safety Production:A Case Study of Huizhou City
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作者 Liqing WANG Cijizhuoma Zhenchang LIU 《Asian Agricultural Research》 2023年第1期8-9,12,共3页
The current situation of grain production in Huizhou City was analyzed firstly,and then the existing problems and challenges of grain safety production were pointed out,such as increases in the pressure to ensure grai... The current situation of grain production in Huizhou City was analyzed firstly,and then the existing problems and challenges of grain safety production were pointed out,such as increases in the pressure to ensure grain safety production and the difficulty of stable development of grain production.Finally,several countermeasures and suggestions for the stable development of grain production were put forward. 展开更多
关键词 Food security Huizhou City Science and technology Grain production capacity
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Tradeoffanalysis of the pork supply and food security under the influence of African swine fever and the COVID-19 outbreak in China 被引量:1
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作者 Huizong Yao Chuanfu Zang +4 位作者 Xiaoxing Zuo Yuyang Xian Yongquan Lu Yutong Huang Xianbing Li 《Geography and Sustainability》 2022年第1期32-43,共12页
China is the world’s largest consumer of pork and grains.However,African swine fever(ASF)and the COVID-19 outbreak have greatly impacted the pork supply and food security in China.How can food security and the pork s... China is the world’s largest consumer of pork and grains.However,African swine fever(ASF)and the COVID-19 outbreak have greatly impacted the pork supply and food security in China.How can food security and the pork supply be ensured under the dual impacts of COVID-19 and ASF?This is a major problem to be urgently solved by the Chinese government.This study indicated that the main pork production and sales areas in China were separated,which reflected the spatial imbalance between the supply and demand.The total area of suitable selected sites for pig farms in China is 21.5 million ha.If only the areas with levels of high and moderate suitability are considered as potential sites for pig farms,the potential pork production can reach 56.1 million tons in China,which is slightly lower than demand.Due to the impact of the ASF epidemic,the food consumed by pigs has been reduced by 34.7 million tons.However,with increasing pork productivity in the future,the self-sufficiency rate of grains may further decline.On the premise that the quality of people’s life is not affected,the diversification of meat supply channels should be realized in an orderly and sustainable way,which might alleviate the pressure on food supply.This study provides a theoretical reference for the spatiotemporal layout of the swine industry and addresses the issue of food security in China under the influence of ASF and the COVID-19 outbreak. 展开更多
关键词 African swine fever COVID-19 outbreak Suitability analysis Food security Pork production potential
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Nε-(carboxymethyl)lysine promotes lipid uptake of macrophage via cluster of differentiation 36 and receptor for advanced glycation end products
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作者 Zhong-Qun Wang Hai-Peng Yao Zhen Sun 《World Journal of Diabetes》 SCIE 2023年第3期222-233,共12页
BACKGROUND Advanced glycation end products(AGEs)are diabetic metabolic toxic products that cannot be ignored.Nε-(carboxymethyl)lysine(CML),a component of AGEs,could increase macrophage lipid uptake,promote foam cell ... BACKGROUND Advanced glycation end products(AGEs)are diabetic metabolic toxic products that cannot be ignored.Nε-(carboxymethyl)lysine(CML),a component of AGEs,could increase macrophage lipid uptake,promote foam cell formation,and thereby accelerate atherosclerosis.The receptor for AGEs(RAGE)and cluster of differentiation 36(CD36)were the receptors of CML.However,it is still unknown whether RAGE and CD36 play key roles in CML-promoted lipid uptake.AIM Our study aimed to explore the role of RAGE and CD36 in CML-induced macrophage lipid uptake.METHODS In this study,we examined the effect of CML on lipid uptake by Raw264.7 macrophages.After adding 10 mmol/L CML,the lipid accumulation in macrophages was confirmed by oil red O staining.Expression changes of CD36 and RAGE were detected with immunoblotting and quantitative real-time polymerase chain reaction.The interaction between CML with CD36 and RAGE was verified by immunoprecipitation.We synthesized a novel N-succinimidyl-4-18Ffluorobenzoate-CML radioactive probe.Radioactive receptor-ligand binding assays were performed to test the binding affinity between CML with CD36 and RAGE.The effects of blocking CD36 or RAGE on CML-promoting lipid uptake were also detected.RESULTS The study revealed that CML significantly promoted lipid uptake by macrophages.Immunoprecipitation and radioactive receptor-ligand binding assays indicated that CML could specifically bind to both CD36 and RAGE.CML had a higher affinity for CD36 than RAGE.ARG82,ASN71,and THR70 were the potential interacting amino acids that CD36 binds to CML Anti-CD36 and anti-RAGE could block the uptake of CML by macrophages.The lipid uptake promotion effect of CML was significantly attenuated after blocking CD36 or RAGE.CONCLUSION Our results suggest that the binding of CML with CD36 and RAGE promotes macrophage lipid uptake. 展开更多
关键词 -(carboxymethyl)lysine Cluster of differentiation 36 Receptor for advanced glycation end products Lipid uptake MACROPHAGE
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社保费负担、创新挤出与企业生产率--基于社保费征管体制改革的研究
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作者 张玲 秦雪征 +1 位作者 温舒 马光荣 《经济科学》 北大核心 2024年第1期146-167,共22页
税务部门全责征收社保费,有助于社保费征缴体系的规范,但社保征缴力度的加强增加了企业税费负担,挤出了企业创新投入,不利于生产率的提升。2019年中国开始全面推行税务部门全责征收社保费,但自2000年起,广东、浙江、福建等六个省份已陆... 税务部门全责征收社保费,有助于社保费征缴体系的规范,但社保征缴力度的加强增加了企业税费负担,挤出了企业创新投入,不利于生产率的提升。2019年中国开始全面推行税务部门全责征收社保费,但自2000年起,广东、浙江、福建等六个省份已陆续完成税务全责征收试点。本文利用1998-2013年中国工业企业数据,使用双重差分模型,评估了税务全责征收社保费改革对企业全要素生产率的影响。结果显示,改革显著降低了企业全要素生产率。政策实施后,企业全要素生产率平均降低16%。进一步检验税务全责征收模式影响企业全要素生产率的机制发现,改革增加了企业的社保费负担,缩减了企业现金流,加深了企业融资约束程度,从而挤出了企业的创新投入,导致企业研发投入和申请专利数量显著下降。本文结论表明,在推行税务全责征收社保费、规范社保征收体系的同时,应考虑激发市场主体的活力,缓释改革对企业生产带来的阵痛,为企业纾困解难。 展开更多
关键词 税务全责征收 企业全要素生产率 融资约束 创新挤出
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劳动力转移对粮食生产韧性的影响研究--基于中国粮食主产区的实证
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作者 蔡林军 文春晖 《中国农机化学报》 北大核心 2024年第3期313-321,共9页
粮食安全是“国之大者”,随着农业劳动力大量转移,粮食生产韧性是否受到影响及受到的影响有多大,已成为新时期的重要议题。基于中国粮食主产区2010-2022年省域面板数据,通过构建主产区粮食生产韧性的综合指标体系,首先使用熵权与变异系... 粮食安全是“国之大者”,随着农业劳动力大量转移,粮食生产韧性是否受到影响及受到的影响有多大,已成为新时期的重要议题。基于中国粮食主产区2010-2022年省域面板数据,通过构建主产区粮食生产韧性的综合指标体系,首先使用熵权与变异系数综合赋权法对其进行测度,其次选用固定效应模型实证检验农业劳动力转移对粮食生产韧性影响的内在逻辑。研究发现:农业劳动力转移有助于主产区粮食生产韧性的提升,且对粮食生产韧性的促进效应在较长时间序列上均稳健成立。具体而言,农业劳动力转移每增加1%,主产区粮食生产韧性水平将会平均增加1.712 0%。研究还发现,北方和南方主产区农业劳动力转移影响粮食生产韧性水平存在明显异质性,北方主产区的提升作用更为显著。因此,进一步引导农业劳动力非农转移推动区域粮食生产韧性水平提升,是新时期保障我国粮食安全的有效途径。 展开更多
关键词 粮食主产区 劳动力转移 粮食生产韧性 粮食安全
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Application of vertically integrated sampling approach to study of new production via ^(234)Th -^(238)U disequilibria 被引量:1
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作者 Chen Feizhou1 Huang Yipu2 Chen Min2 (1. College of Fishery Science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第2期37-44,共8页
The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in... The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale. 展开更多
关键词 New production vertically integrated Sampling approach ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea
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The effectiveness of the department of defense's field manual 3-11 in detecting,deterring and degrading the breach of a combat base by a human-borne with bioagent(HBBA):perceptions of security personnel
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作者 George Edafese Alakpa John W.Collins Jr 《Journal of Medical Colleges of PLA(China)》 CAS 2016年第2期66-72,共7页
Background: The department of defense's field manual(FM) 3-11 is among the military's field manuals for preparing for, reacting to and recovering from chemical, biological, radiological and nuclear attacks. Si... Background: The department of defense's field manual(FM) 3-11 is among the military's field manuals for preparing for, reacting to and recovering from chemical, biological, radiological and nuclear attacks. Since post 9-11, U.S. military service members have been deployed in the global war on terrorism. This study attempted to determine the effectiveness of the FM 3-11 in detecting, deterring or preventing a human-borne with bioagent(HBBA) terrorist breach at an entry control point(ECP).Methods: This time-specific, cross-sectional study disseminated a validated survey tool with Cronbach's α>0.82 to respondents who have had antiterrorism training and combat ECP experience. The return rate was greater than 75.0%; however, many of the respondents failed to meet the inclusion criteria. Consequently, only 26 questionnaires were included in the sample.Results: The results revealed that while over 60.0% of the respondents either strongly agreed or agreed that biointelligence, the deployment of biodetectors and the use of biowarning systems could be effective in preventing an ECP breach by a terrorist with a bioagent, the use of protective equipment and immunization to decontaminate service members or other tactics, techniques and procedures(TTPs) would never prevent a breach. A large percentage of respondents claimed that soldiers at the ECP lacked the devices or the knowledge to detect an HBBA at an ECP, and 72.0% suggested modifying current ECP TTPs to include education, training and equipment for security personnel at military base ECPs.Conclusion: If obtained from appropriate sources and communicated to the personnel at the ECP in an effective or timely manner, the possible effectiveness of certain TTPs in the FM 3-11, specifically FM 3-11.86(intelligence), might increase. 展开更多
关键词 Do D FM 3-11 BIOTERRORISM Breach of COMBAT ECP HBBA TERRORIST security PERSONNEL Perception
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The Impact of Climate Change on China's Grain Market and Food Security-- A CGE Model Approach 被引量:1
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作者 Huang Delin Li Ximing +3 位作者 Li Xinxing Li Xiangyang Cai Songfeng Wang Chenggang 《Chinese Business Review》 2014年第7期427-441,共15页
关键词 气候变化影响 中国食品 粮食市场 CGE模型 数值模拟方法 粮食生产 宏观经济 家庭消费
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区块链技术解决农产品信任危机探索--以临安山核桃为例
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作者 陈榆城 谢瑜 +1 位作者 姚嘉艺 杨雪雁 《智慧农业导刊》 2024年第6期5-10,共6页
近几年区块链技术在农业领域的应用案例越来越多。理论上区块链技术解决农产品信任危机,在于通过信息来源可信、信息存储可信、信息传输可信和信息管理可信解决农产品产业链的信息可信度问题。该文通过案例研究法分析区块链技术在应用... 近几年区块链技术在农业领域的应用案例越来越多。理论上区块链技术解决农产品信任危机,在于通过信息来源可信、信息存储可信、信息传输可信和信息管理可信解决农产品产业链的信息可信度问题。该文通过案例研究法分析区块链技术在应用过程中如何解决信息安全问题。该文以临安山核桃产业“数字大脑”为研究对象,在传统临安山核桃产业安全痛点分析基础上,提出区块链应用数据的处理框架,并从身份认证、品质验证、流程溯源和审计监管4个功能,探讨区块链技术对山核桃信息可信问题的解决之路。该文最后也提出区块链技术在农业领域应用中尚存在的成本障碍和管理规范化问题,并提出对应解决建议。 展开更多
关键词 区块链 农产品安全 信息可信 数字大脑 山核桃身份认证
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Special Plan for Population,Employment and Social Security Between 2001-2005
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《China Population Today》 2002年第1期2-4,共3页
关键词 security Special Plan for Population Employment and Social security Between 2001-2005
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THE BROAD-BAND CCD PHOTOMETRY AND DUST PRODUCTION RATES OF COMET HALE-BOPP
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作者 Huang Keliang 1 Hu Jingyao 2 Zhou Hongnan 1 (1. Department of Physics, Nanjing Normal University, Nanjing 210097) (2. Beijing Observatory, Chinese Academy of Sciences, Beijing 100080) 《中国科学院上海天文台年刊》 2000年第S1期44-50,共7页
Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp ... Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/dt~1.5×10 5 kgs -1, R n~35.5km, and M n~5.65×10 16kg. 展开更多
关键词 COMET HALE-BOPP - CCD PHOTOMETRY - DUST production rate
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China Initiates Voluntary Certification of Public Security Products
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《China Standardization》 2004年第4期16-16,共1页
关键词 security China Initiates Voluntary Certification of Public security products
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