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An Analysis of Using Blockchain to Enhance Trust in Agricultural Supply Chain Finance: Constraints and Mechanisms for Removing the Constraints

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Contemporary Social Sciences 2025年第01期 69-82页

作者： Wang Xingyu Ren Le li tiantian Henan University

This paper begins with a discussion of the trust issues that agricultural supply chain finance faces. It then examines the constraints of using blockchain technology to enhance trust in agricultural supply chain finance in accordance with the technological and institutional logic of combining blockchain with supply chains. This study then proposes the creation of an agricultural “blockchain + supply chain” information service platform and a financing trust mechanism that can effectively ensure the authenticity of the initial information input on the blockchain, consistency between onchain transaction data and off-chain physical transactions, the controllability of risks in the set up and execution of smart contracts, and the removal of information constraints, resource allocation constraints, and institutional constraints in the agricultural supply chain financing. This aims to improve the efficiency of financing in agricultural supply chains and contribute to the industrial development of rural areas and rural revitalization.

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A Public Health Initiative for Action on Early Warning of Heat Health Risks

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China CDC weekly 2023年第29期5卷 639-641页

作者： tiantian li China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

Heatwaves,also known as extreme heat events,represent periods of excessively hot weather and rank among the most perilous natural hazards worldwide due to their increased mortality risk,especially among vulnerable *** frequency,intensity,and geographical spread of heatwaves are noticeably increasing in the setting of climate change(1).

关键词： weather setting extreme

中国城市新质生产力水平测度、区域分异及障碍因子分析

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工业技术经济 2025年第3期44卷 24-33页

作者：张源野叶阿忠朱灵群李田田福州大学经济与管理学院福州350108

新质生产力是契合新发展要求的先进生产力,也是推进经济高质量发展的关键驱动。本文从物质生产力、精神生产力、生态生产力和社会生产力构建新质生产力评价指标体系,利用CRITIC法对2011~2022年中国284个城市的新质生产力水平进行测度,采... 详细信息

新质生产力是契合新发展要求的先进生产力,也是推进经济高质量发展的关键驱动。本文从物质生产力、精神生产力、生态生产力和社会生产力构建新质生产力评价指标体系,利用CRITIC法对2011~2022年中国284个城市的新质生产力水平进行测度,采用Kernel密度估计、Dagum基尼系数、方差分解和障碍因子诊断等方法探究其动态演进、区域差异和障碍因子。研究发现:新质生产力总体水平呈持续增长态势,四大区域呈“东部-中部-东北-西部”递减状态;新质生产力水平的总体差异呈现波动下降的趋势,区域间差异是最主要空间来源,物质生产力差异是最主要结构来源;科技存量、能源结构和工业数字化是制约中国新质生产力发展的主要障碍因子。

关键词：新质生产力分布动态区域差异障碍因子分析物质生产力精神生产力生态生产力社会生产力

Joint computation offloading and resource allocation in vehicular edge computing networks

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Digital Communications and Networks 2023年第6期9卷 1399-1410页

作者： Shuang liu Jie Tian Chao Zhai tiantian li School of Information Science and Engineering Shandong Normal UniversityJinan250358China School of Information Science and Engineering Shandong UniversityQingdao266237China

Vehicular Edge Computing(VEC)is a promising technique to accommodate the computation-intensive and delaysensitive tasks through offloading the tasks to the RoadSide-Unit(RSU)equipped with edge computing servers or neighboring ***,the limited computation resources of edge computing servers and the mobility of vehicles make the offloading policy design very *** this context,through considering the potential transmission gains brought by the mobility of vehicles,we propose an efficient computation offloading and resource allocation scheme in VEC networks with two kinds of offloading modes,i.e.,Vehicle to Vehicle(V2V)and Vehicle to RSU(V2R).We define a new cost function for vehicular users by incorporating the vehicles’offloading delay,energy consumption,and expenses with a differentiated pricing strategy,as well as the transmission *** optimization problem is formulated to minimize the average cost of all the task vehicles under the latency and computation capacity constraints.A distributed iterative algorithm is proposed by decoupling the problem into two subproblems for the offloading mode selection and the resource *** theorybased and Lagrangian-based algorithms are proposed to solve the two subproblems,*** results show the proposed algorithm achieves low complexity and significantly improves the system performance compared with three benchmark schemes.

关键词： Vehicular edge computing Task offloading Matching theory Lagrangian method Distributed algorithm

Increment-Dimensional Scaled Boundary Finite Element Method for Solving Transient Heat Conduction Problem

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 1073-1079页

作者： li Fengzhi li tiantian Kong Wei Cai Junfeng College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China College of Aeronautic Science and Engineering Beihang UniversityBeijing 100191P.R.China The 610 Research Institute of Chinese Aeronautical Establishment Xiangyang 441000P.R.China

An increment-dimensional scaled boundary finite element method (ID-SBFEM) is developed to solve the transient temperature *** improve the accuracy of SBFEM,the effect of high frequency factor on dynamic stiffness is considered,and the first-order continued fraction technique is *** the derivation,the SBFE equations are obtained,and the dimensions of thermal conduction,the thermal capacity matrix and the vector of the right side term in the equations are *** example is presented to illustrate the feasibility and good accuracy of the proposed method.

关键词： heat conduction scaled boundary finite element method(SBFEM) temperature field accuracy

One and Two-Weight Z2R2 Additive Codes

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Chinese Journal of Electronics 2021年第1期30卷 72-76页

作者： li tiantian SHI Minjia liN Bo WU Wenting School of Mathematical Sciences Anhui University School of Wendian Anhui University

This paper is devoted to the construction of one and two-weight Z2R2additive codes, where R2=F2[v]/(v~4). It is a generalization towards another direction of Z2Z4codes(S.T. Dougherty, H.W. liu and L. Yu,"One weight Z2Z4additive codes", Applicable Algebra in Engineering, Communication and Computing, Vol.27,No.2, pp.123–138, 2016). A Mac Williams identity which connects the weight enumerator of an additive code over Z2R2and its dual is established. Several construction methods of one-weight and two-weight additive codes over Z2R2are presented. Several examples are presented to illustrate our main results and some open problems are also proposed.

关键词： dual codes additive code weight enumerator two-weight additive codes

Enhanced dewaterability of waste activated sludge by UV assisted ZVI-PDS oxidation

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Journal of Environmental Sciences 2022年第3期34卷 152-164页

作者： Yanping Zhang tiantian li Jiayu Tian Huichun Zhang Fen li Jiahua Pei School of Civil Engineering and Transportation Hebei University of TechnologyTianjin 300401China Department of Civil and Environmental Engineering Case Western Reserve UniversityClevelandOH 44106USA College of Chemical and Environmental Engineering Harbin University of Science and TechnologyHarbin 150000China

Ultraviolet(UV)assisted zero-valent iron(ZVI)-activated sodium persulfate(PDS)oxidation(UV-ZVI-PDS)was used to treat waste activated sludge(WAS)in this *** dewaterability performance and mechanism of WAS dewatering were *** results showed that UV-ZVI-PDS can obtain better sludge dewatering performance in a wide pH range(2.0-8.0).When the molar ratio of ZVI/PDS was 0.6,UV was 254nm,PDS dosage was 200 mg/g TS(total solid),pH was 6.54,reaction time was 20 min,the CST(capillary suction time)and SRF(specific resistance to filtration)were decreased by 64.0%and 78.2%,*** molar ratio of ZVI/PDS used in this paper is much lower than that of literatures,and the contents of total Fe and Fe^(2+) in sludge supernatant remained at a low level,as 3.7 mg/L and 0.0 mg/*** analysis of extracellular polymeric substances(EPS),scanning electron microscope(SEM)and particle size distribution showed that the EPS could be effectively destroyed by UV-ZVI-PDS,the sludge flocs broken down into smaller particles,cracks and holes appeared,and then the bound water was *** the same time,the highly hydrophilic tightly bound-EPS(TB-EPS)were converted into loosely bound EPS(LB-EPS)and soluble EPS(S-EPS).During sludge pretreated by UV-ZVI-PDS,positively charged ions,such as Fe^(2+),Fe^(3+) and H^(+),produced in the reaction system could reduce the electronegativity of sludge surface,promote sludge particles aggregation,and then enhanced the sludge dewaterability.

关键词： Sludge dewatering Persulfate Zero-valent iron UV Extracellular polymeric substances

The Impact of Irrigation on Bacterial Community Composition and Diversity in liaohe Estuary Wetland

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Journal of Ocean University of China 2018年第4期17卷 855-863页

作者： li tiantian HU Hong li Zhengyan ZHANG Jianye li Dong College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Colleget of Marine life Sciences Ocean University of ChinaQingdao 26610Q China Institute of Wetland Science Panjin 124000China

In this study, the sequencing of 16S ribosomal DNA was used to characterize the soil bacterial community composition and diversity in liaohe estuarine wetland. Soil samples were taken from different locations in the wetland dominated by reed. Moreover, the soil quality parameters were evaluated(p H, moisture, organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus). The results showed that the organic matter and nutrient contents were significantly higher in irrigated wetland than those in natural wetland. Major phylogenic groups of bacteria in soil samples including Proteobacteria, Acidobacteria, Gemmatimonadetes, Actinobacteria and Cyanobacteria were analyzed and we found that Proteobacteria was the most abundant in the community, and the phylum Acidobacteria was more abundant in irrigated wetland. Beta diversity analyses indicated that the soil bacterial community was mainly affected by sampling sites rather than seasons. In general, the bacterial community in natural wetland was not significantly different with that in artificial irrigated wetland. Artificial hydraulic engineering irrigated according to the water requirement rule of reed, increased the production of reeds, changed the way of wetland soil material input, but the diversity of bacterial community kept stable relatively.

关键词： soil bacterial community liaohe estuary wetland 16S rDNA sequencing nutrient

Max-Min Fair RIS-Aided Rate-Splitting Multiple Access for Multigroup Multicast Communications

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China Communications 2023年第1期20卷 184-198页

作者： tiantian li Haixia Zhang Shuaishuai Guo Dongfeng Yuan School of Information Science and Engineering Shandong Normal UniversityJinan 250014China School of Control Science and Engineering Shandong UniversityJinan 250061China Shandong Key Laboratory of Wireless Communication Technologies (Shandong University)Jinan 250061China

Rate-splitting multiple access(RSMA)can cope with a wide range of propagation conditions in multigroup multicast communications through rate splitting *** breakthrough the grouprate limited bottleneck,reconfigurable intelligent surface(RIS)technique can be introduced to assist wireless communications through enhancing the channel *** RIS-aided RSMA multigroup multicasting,how to provide fair and high-quality multiuser service under power and spectrum constraints is *** this paper,we propose a max-min fair RIS-aided rate-splitting multiple access(MMF-RISRSMA)scheme for multigroup multicast communications,where the rate fairness is obtained by maximizing the minimum *** doing so,we jointly optimize the beamformers,the rate splitting vector at the transmitter,as well as the phase shifts at *** solve it,we divide the original optimization problem into two subproblems and alternately optimize the *** beamforming and rate splitting optimization subproblem is solved by using the successive convex approximation *** phase shift optimization subproblem is solved through the penalty function method to achieve a rank-one locally optimal *** demonstrate that the proposed MMF-RIS-RSMA scheme can obtain significant performance gain in terms of the minimum group-rate.

关键词： multigroup multicast communications rate-splitting multiple access(RSMA) reconfigurable intelligent surfaces(RIS) max-min fairness(MMF)