Map Scale Effects on Soil Phosphorus Storage Estimation in the Uplands of Eastern China

Liming Zhang,Jiajia Li,Dongsheng Yu,Xuezheng Shi,Shihe Xing,Shengxiang Xu,Yongcun Zhao,Fengyun Zhang 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Reachable workspace determination for a spatial hyper-redundant manipulator formed by several parallel manipulators

Bo Hu,He Cui,Dongsheng Shi,Dongsheng Zhang,Andong Wang,Ying Wang,Qian Zhang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.2

Solving the reachable workspaces of spatial hyper-redundant manipulators (SHRMs) formed by serially connected parallel manipulators is an important and challenging work. This study addresses the issue on reachable workspaces and establishes a novel CAD-VBbased workspace determination system for determining the reachable workspaces of SHRMs. The reachable workspace determination of a novel (3-RPS)+(3-SPR)+(3-RPS) SHRM, a triple delta-type SHRM, and a novel (3-RRS)+(3-SPR)+(3-RRS) SHRM shows the generality and effectiveness of the proposed approach. The system proposed in this study can contribute to reachable workspace analysis for SHRMs.

Adsorption properties of Friedel’s salt for the nitrate in the landfill

Dongsheng Shen,Jun Yao,Qingna Kong,Huayue Zhu,Zhen Zhang 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.2

Adsorption characteristics of nitrate on Friedel’s salt under the landfill circumstance were investigated to explore the effect of Friedel’s salt on the migration of nitrate in the landfill. Friedel’s salt was synthesized by a coprecipitation method and characterized by XRD and FTIR spectroscopy. The kinetics and isotherm of the adsorption were studied. The effect of the variation of landfill circumstance on the adsorption was also discussed. The result showed that the adsorption capacity of Friedel’s salt for nitrate was 2.494mg g−1. The adsorption process was exothermic and could be well described by pseudo-second-order kinetics and Langmuir-Freundlich equation. Cl− could enhance the adsorption, while SO4 2−, PO4 3− and organic matter could restrict the adsorption. The results suggested that the migration of nitrate in the landfill could be altered by Friedel’s salt, which was related to the variation of the landfill circumstance.

Priority Selection Rating of Sampling Density and Interpolation Method for Detecting The Spatial Variability of Soil Organic Carbon

Dongsheng Yu,Zhongqi Zhang,Xuezheng Shi 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

The vertical distribution and temporal occurrence of three types of rice planthoppers in Shanghai

Wang Dongsheng,Wu Xiangwen,Yuan Yongda,Zhang Tianshu,Shen Huimei,Du Xingbin,Teng Haiyuan,Chang Xiaoli 한국곤충학회 2022 Entomological Research Vol.52 No.1

In this study, we investigated the dynamic occurrence and vertical distribution of three types of rice planthoppers (Nilaparvata lugens, Sogatella furcifera,and Laodelphax striatellus) in Shanghai, China. Our results showed that S. furcifera and L. striatellus infested the lower part of rice plants in the early development stage, S. furcifera and L. striatellus inhabited every part of rice in the middle development stage, and L. striatellus and N. lugens formicated in the upper part of the rice plant in the posterior development stage. The populations of rice planthoppers were larger in July and September, Where more than 600 adult and nymphal planthoppers, per a hundred hills of rice, were found in late July, and out of the 600, the majority were the nymphs of S. furcifera and L. striatellus. S. furcifera was mainly found from July to October, L. striatellus during the rice development, and N. lugens after September, during which their maximal individual number, per a hundred hills of rice, was 480, 220, less than 50, respectively. In addition, our results showed that adult rice planthoppers were mostly observed from late August to mid-October with the highest population being found during mid to late September. The adult S. furcifera, L. striatellus,andN. lugens were mostly observed in August and September, from August to October, and past mid-September, respectively. Moreover, the number of adult L. striatellus that were sticking to yellow sticky card was significantly higher than that of S. furcifera and N. lugens.

Detection and location of bolt group looseness using ultrasonic guided wave

Yue Zhang,Dongsheng Li,Xutao Zheng 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.24 No.3

Bolted joints are commonly used in civil infrastructure and mechanical assembly structures. Monitoring and identifying the connection status of bolts is the frontier problem of structural research. The existing research is mainly on the looseness of a single bolt. This article presents a study of assessing the loosening/tightening health state and identifying the loose bolt by using ultrasonic guided wave in a bolt group joint. A bolt-tightening index was proposed for evaluating the looseness of a bolt connection based on correlation coefficient. The tightening/loosening state of the bolt was simulated by changing the bolt torque. More than 180 different measurement tests for total of six bolts were conducted. The results showed that with the bolt torque increases, value of the proposed bolt-tightening index increases. The proposed bolt-tightening index trend was very well reproduced by an analytical expression using a function of the torque applied with an overall percentage error lower than 5%. The developed damage index based on the proposed bolt-tightening index can also be applied to locate the loosest bolt in a bolt group joint. To verify the effectiveness of the proposed method, a bolt group joint experiment with different positions of bolt looseness was performed. Experimental results show that the proposed approach is effective to detect and locate bolt looseness and has a good prospect of finding applications in real-time structural monitoring.

Modeling and Deep Reinforcement Learning Based Control Parameter Tuning for Voltage Source Converter in a Renewable Energy Generation System

Xing Yankai,Zhang Guangdou,Wang Baolu,Li Jian,Bamisile Olusola,Cai Dongsheng,Huang Qi 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.2

The fast response and low inertia characteristics of converter-based generation (CBG) lead to a new stability issue that limits renewable energy development. This is due to the fact that, using traditional control theory as basic, there is no unifed and efective way to linearize the electronic device and set the parameters in the existing analysis method. In order to optimize the parameters tuning process of the converter control, a benchmark model is adopted in this paper, and the linearization model is updated by selecting suitable variables and detailed with considering the infuence of resistance of the converter. Based on this model, the stability margin related to the parameters of the system is analyzed. Furthermore, to consider more dynamics and make the converter controller focus on the topologies and scenarios, the dynamic response of a disturbance in the grid is selected as the iteration state to design a controller using Deep Reinforcement Learning (DRL). That is, the cascaded voltage and current control along with droop control are tuned by Deep Deterministic Policy Gradient (DDPG) algorithm in the linearized model. The validation tests are carried out on the nonlinear model in Simulink test and real-time platform. They indicate that the proposed linearization and tuning method provides more accuracy and stability for the power system in various grid conditions.

Modification of biomass furan-based PEF copolyester with glycerol

Chengzhi Liu,Dongsheng Zhao,Maliang Zhang,Kunmei Su,Zhenhuan Li 한국고분자학회 2024 Macromolecular Research Vol.32 No.1

In order to solve the problem of low molecular weight in the synthesis of poly(ethylene 2,5-furandicarboxylate) (PEF) copolyester with titanium-based catalysts, this paper introduce an appropriate amount of glycerol (GC) into PEF to branch the straight chain polyester though the transesterification-melt polycondensation method, which solve the problem of low resin viscosity and low molecular weight. The structures of the copolymers were characterized by 1H-NMR and 13C-NMR, and the results showed that the modified PEF copolyesters and poly(ethylene-co-glycerol 2,5-furandicarboxylate) (PEGFs) were successfully prepared. The intrinsic viscosity ([η]) of PEGFs copolyesters was characterized by Ubbelohde viscosity, and the results showed that the copolyester [η] was increased from 0.25 dL/g to 0.755 dL/g. The thermal properties of copolyester were characterized by differential scanning calorimetry and thermo gravimetry, and it was found that the glass transition temperature of PEGFs copolyester increased from 67.8 °C to 89.5 °C, and the maximum pyrolysis rate temperature increased from 386.6 °C to 402.8 °C. We characterized the UV resistance of PEGFs copolyester, and the results showed that PEGFs copolyester could be well degraded under ultraviolet light.

The Prediction of Code Clone Quality Based on Bayesian Network

Dongrui Liu,Dongsheng Liu,Liping Zhang,Min Hou,Chunhui Wang 보안공학연구지원센터 2016 International Journal of Software Engineering and Vol.10 No.4

This paper researched on the quality of code clone in the software, evaluated the code clone quality of the current versions. Then using Bayesian network to train the existing sample data to get the prediction model of code clone that is able to predict the quality. The prediction results are able to help developers decide which code clone should be reconstructed or efficiently reused. The experiment shows that the method can be used to predict the quality of code clone in software more accurately.

Evidence for relaxed selection of mitogenome in rapid‑flow cyprinids

Yao Lu,Hu Xing,Dongsheng Zhang 한국유전학회 2019 Genes & Genomics Vol.41 No.7

Background Hypoxia adaptation is developed in many fish species, which helped them to habitat most of water bodies. However, fishes living under high oxygen concentration may lose this feature. Rapid flows provide high level and stable dissolved oxygen, which facilitate organism’s oxygen supply and energy production. Previous studies showed that fish species from rapid-flow habitats exhibited lower hypoxia tolerance compared with fish from intermediate- and slow-flow habitats. Mitochondrial genomes code 13 key components in oxidative phosphorylation pathway; these genes may be under relaxed selection in rapid-flow species. Objectives The primary objectives of this study is to investigate the evolutionary patterns of the 13 mitochondrial OXPHOS genes among nine cyprinids from different water bodies and to test the hypotheses that mitochondrial OXPHOS genes may experience relaxed selection in rapid-flow habitats. Methods We classified nine cyprinid fish species into three groups based on their habitats: rapid-flow, intermediate-flow and slow-flow. To detect relaxed selections, we investigated the 13 protein-coding genes with codon evolution programs RELAX; to estimate evolutionary rates among the cyprinids, free-ratio model in Codeml program was applied; Branch-site models were applied to detect positive selection sites. The polymorphisms of homologous sites were evaluated with PROVEAN program and projected to 3D structure prediction of the proteins using SWISS-MODEL. Results We found that nine out of the 13 genes are under relaxed selection in rapid-flow species. Furthermore, dN, dS and dN/dS are relatively increased when compared with those of intermediate-flow species. More amino acid polymorphic sites are presented in rapid-flow species than in intermediate- and slow-flow species. Furthermore, rapid-flow species had more deleterious substitutions than other groups. 3D structure prediction of these proteins and projection of the polymorphic sites indicated that these sites were randomly distributed, suggesting relaxed functional constraints of these proteins in rapid-flow species. Conclusion Our results suggest that mitochondrial genes are under relaxed selection in rapid-flow cyprinids.