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An Improved Virtual Inertia Algorithm of Virtual Synchronous Generator

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 377-386页

作者： Haizhen Xu Changzhou Yu Chun Liu qinglong wang Xing Zhang the Department of Electronic Information and Electrical Engineering Hefei UniversityHefeiChina Anhui Provincial Engineering Laboratory of Renewable Energy and Industrial Energy Conservation Hefei University of TechnologyHefeiChina

Virtual synchronous generator(VSG)simulates the first-order motion equation of a synchronous generator(SG)with the *** can improve the system voltage and frequency support capabilities of a microgrid or a weak *** is now widely applied at a high penetration level of distributed generation(DG)***,because there is a contradiction between active power steady-state deviation of VSG and dynamic impact regulation,the VSG running in grid-connected mode with existing strategies cannot meet the steady and dynamic control ***,an improved virtual inertial control strategy of VSG is proposed in this *** active power impact is reduced effectively under the circumstance of damping coefficient Dωequal to 0 and a large inertia,thus the dynamic characteristic of active power is improved and its steady-state characteristic is ***,based on the analysis of the damping coefficient effect on the system dynamic process,two forms of improved virtual inertia algorithms are put forward by cascading a differential link into different positions of the first-order virtual inertia forward ***,by comparing the characteristics of the system with the two improved algorithms,the improved virtual inertial strategy based on differential compensation is proven to be better,and the design of its parameters is ***,simulation and experimental results verify the effectiveness of the proposed algorithm.

关键词： Virtual synchronous generator(VSG) virtual inertia microgrid distributed generation(DG)

Existence and global asymptotic stability of positive almost periodic solutions of a two-species competitive system

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International Journal of Biomathematics 2014年第4期7卷 85-102页

作者： qinglong wang Zhijun Liu Zuxiong Li Robert A. Cheke Department of Mathematics Hubei University for Nationalities 445000 Enshi Hubei P. R. China Natural Resources Institute University of Greenwich at Medway Central Avenue Chatham Maritime Chatham Kent ME44TB UK

The asymptotic behavior of an almost periodic competitive system is investigated. By using differential inequality, the module containment theorem and the Lyapunov function, a good understanding of the existence and global asymptotic stability of posi- tive almost periodic solutions is obtained. Finally, an example and numerical simulations are performed for justifying the theoretical results.

关键词： Competitive system almost periodic solution existence global asymptoticstability.

3D Printed Bioinspired Stents with Photothermal Effects for Malignant Colorectal Obstruction

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Research 2022年第4期2022卷 451-462页

作者： Cheng Lin Zhipeng Huang qinglong wang Wantao wang Wenbo wang Zhen wang Liwu Liu Yanju Liu Jinsong Leng Centre for Composite Materials and Structures Harbin Institute of TechnologyNo.2 Yikuang StreetHarbin 150001China Tangdu Hospital of the Air Force Military Medical University No.1Xinsi RoadXian 710038China The First Afliated Hospital of Harbin Medical University No.23 Youzheng StreetNangang DistrictHarbin 150001China The Second Afliated Hospital of Harbin Medical University No.246 Xuefu StreetNangang DistrictHarbin 150001China Department of Astronautical Science and Mechanics Harbin Institute of TechnologyNo.92 West Dazhi StreetHarbin150001China

Stent placement is an effective palliation therapy for malignant colorectal ***,recurrent obstruction is a common severe complication caused by tumor ingrowth into the stent *** covered stents play a part in preventing the tumor from growing inward but at the expense of significantly increasing the risk of stent ***,there is an urgent demand to develop stents with sustained antitumor and antimigration ***,we propose a facile method for fabricating multifunctional bioinspired colorectal stents using 3D printing *** by high-adhesion biological structures(gecko feet,tree frog toe pads,and octopus suckers)in nature,different types of bioinspired colorectal stents are designed to reduce *** functionalization with graphene oxide(GO),bioinspired colorectal stents show excellent and controllable photothermal performance,which is validated by effective ablation of colon cancer cells in vitro and tumors in ***,the bioinspired colorectal stents demonstrate the feasibility of transanal placement and opening of the obstructed *** importantly,the facile manufacturing process of multifunctional bioinspired colorectal stents is appealing for mass production,Hence,the developed multifunctional bioinspired colorectal stents exhibit a highly promising potential in clinical applications.

关键词： colorectal colon sustained

Effect of Stocking Density on Water Quality and(Growth, Body Composition and Plasma Cortisol Content) Performance of Pen-Reared Rainbow Trout(Oncorhynchus mykiss)

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Journal of Ocean University of China 2016年第4期15卷 667-675页

作者： LIU Qun HOU Zhishuai WEN Haishen LI Jifang HE Feng wang Jinhuan GUAN Biao wang qinglong College of Fisheries Ocean University of China Key Laboratory of Mariculture Ministry of EducationOcean University of China

The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout(Oncorhynchus mykiss). Pen-reared trout were stocked in densities of 40, 60, 80 fish individuals m^(-3)(4.6, 6.6, 8.6 kg m^(-3), SD1, SD2 and SD3 groups, respectively) for 300 days. Compared to the water from SD1 and SD2, that from SD3 exhibited significantly higher NH_4^+-N content and COD(chemical-oxygen-demand), and a significant reduction of dissolved oxygen in day 180(40.6 kg m^(-3)). Stocking density was significantly associated with body weight, standard length, VSI(viscerosomatic index), CF(condition factor) and FC(food coefficient) in group SD3, particularly in day 240 and day 300(45 or 49.3 kg m^(-3)). Increased crude fat and decreased crude protein were displayed in high density group when the density reached to 36 kg m^(-3). As a cumulative effect of density-related stress, VSI, CF, FC, moisture, and crude protein content varied over time in each density group(SD1, SD2, and SD3). In summary, trout exhibited a better growth performance in low density(26.3 kg m^(-3)) than those reared in high densities(36 and 45 kg m^(-3)). The results indicate that rainbow trout(114.44 g ± 6.21 g, 19.69 cm ± 0.31 cm) initially stocked in 6.6 or 8.6 kg m^(-3) should be lightened to less than 36 kg m^(-3) after an intensive rearing for 240 days.

关键词： Oncorhynchus Growth trout crude initially displayed varied length dissolved moisture

GC-MS Analysis of Liposoluble Constituents from Calotropis gigantea Roots

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Medicinal Plant 2017年第6期8卷 10-12页

作者： Maoyuan wang Qing Yang qinglong wang Xiaoxia YAN Jianrong wang Zhunian wang Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China

[Objectives] To effectively develop Calotropis gigantea resources and find the biological active constituents with medicinal value.[Methods]The liposoluble constituents from C. gigantea roots were studied by GC-MS for the first time. [Results] 62 constituents were separated and identified from C. gigantea roots,amounting to 60. 43% of the total constituents,α-amyrin( 4. 18%),ethyl palmitate( 3. 49%),1,7-dimethyl-naphthalene( 3. 06%) were the main liposoluble constituents. [Conclusions] Cardiac glycoside was mainly found in methanol extracts and not detected in liposoluble constituents by extraction of petroleum ether. However,the present study found another component of low toxicity—naphthalene and its derivatives.

关键词： Calotropis gigantea Liposoluble constituents GC-MS

Development and Processing of Millettia speciosa Instant Tea

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Asian Agricultural Research 2017年第3期9卷 102-105页

作者： Maoyuan wang Qing YANG qinglong wang Xiaoxia YAN Jianrong wang Zhunian wang Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Tropical Crops Germplasm Resources UtilizationMinistry of Agriculture

This paper analyzed the effect of raw material crushing fineness,cooking time,ethanol content during ethanol precipitation and other factors on the preparation of raw material extract from Millettia speciosa Champ. instant tea. The raw materials of Millettia speciosa Champ.,Philippine flemingia root and radix fici simplicissimae were crushed into 10 mesh or finer powder,and cooked for 60 min. During ethanol precipitation,the ethanol content was about 50% to 70%,standing 12 h. The ophiopogon root was cooked in 1∶ 15 boiling water for 45 min,and chrysanthemum was leached for 45 min with 1∶ 20 demineralized water at 80 ℃. After concentration,preparation and spray drying,the finished Millettia speciosa Champ. instant tea was created. The detection of each product index indicated that Millettia speciosa Champ. instant tea had good taste and flavor,and there were no heavy metals,harmful substances and excessive microbes,thereby showing that the raw material of Millettia speciosa Champ. instant tea was selected reasonably,the mixture ratio was rational,and the processing technology was of some security,stability and maturity,which provided a theoretical basis for its development and application.

关键词： Millettia speciosa Champ Instant tea Processing technology Index detection

GC-MS Analysis of Liposoluble Constituents from Buds,Flowers and Fruits of Millettia speciosa Champ.

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Medicinal Plant 2017年第4期8卷 10-14页

作者： Maoyuan wang Qing YANG qinglong wang Xiaoxia YAN Jianrong wang Zhunian wang Key Laboratory of Tropical Crops Germplasm Utilization Ministry of Agriculture/Tropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural Sciences

[Objectives] To study the material foundation of liposoluble constituents from buds,flowers and fruits of Millettia speciosa *** provide a reference for the development of flowers and fruits of Millettia speciosa Champ.[Methods]The liposoluble constituents were extracted from buds,flowers and fruits of Millettia speciosa by Soxhlet extraction and solvent extraction method,and analyzed by GC-MS.[Results]24 compounds were identified from the liposoluble constituents of buds,accounting for 88. 31 % of the total liposoluble constituents,mainly comprising alkanes and olefins compounds( 52. 00%) and alcohols compounds( 17. 46%); 29 compounds were identified from the liposoluble constituents of flowers,accounting for 91. 38 % of the total liposoluble constituents,mainly comprising alkanes and olefins compounds( 60. 64%) and alcohols compounds( 17. 17%); 32 compounds were identified from the liposoluble constituents of fruits,accounting for 80. 01 % of the total liposoluble constituents,mainly comprising alkanes and olefins compounds( 32. 56%),phenyl and its derivatives compounds( 22. 46%) and fatty acids compounds( 12. 54%). 6 compounds were common in buds,flowers and fruits. [Conclusions] Although there were some differences in liposoluble constituents from flowers,fruits,leaves and roots of Millettia speciosa Champ.,the different parts of Millettia speciosa Champ. had development value.

关键词： Millettia speciosa Champ Buds Flowers Fruits GC-MS Liposoluble constituents

Geochemical evidence of paleogeography and paleoclimate during deposition of the 2nd Member of Kongdian Formation in Kongnan area

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Global Geology 2007年第1期10卷 48-54页

作者： Qinghua YAN Jing SUN Xudong ZHANG qinglong MENG Man wang College of Earth Sciences Jilin University Changchun 130061 China

The 2nd Member of Kongdian Formation has been made up of a large number of oil shale and mudstone in the Kongnan aera of Huanghua depression around the Bohai *** the Kongnan area,the lake basins were very large and deep during the deposition of the 2nd Member of Kongdian *** that period,the lakes were sealed,uncommunicated with the sea water and the paleoclimate was very warm and wet in Kongnan *** the content of the trace element and the rare earth element,carbon and oxygen isotope in the disquisition,The authors prove the two views correct.

关键词： Kongnan the 2nd Member of Kongdian Formation trace element rare earth element carbonand oxygen isotopes paleoclimate palaeogeography

面向C4ISR系统联合作战的跨组织进程互操作研究

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系统工程理论与实践 2016年第3期36卷 805-816页

作者：禹明刚王智学王庆龙解放军理工大学指挥信息系统学院南京210007

军事组织间的互操作是联合作战成败的关键,瞬息万变的战场环境中各组织如何协调、整合业务进程以完成共同的使命任务对协作模式的灵活性,协作组织的自主性等提出了更高的要求.传统的基于公共视角的业务进程协作模式已不能适应现代联合... 详细信息

军事组织间的互操作是联合作战成败的关键,瞬息万变的战场环境中各组织如何协调、整合业务进程以完成共同的使命任务对协作模式的灵活性,协作组织的自主性等提出了更高的要求.传统的基于公共视角的业务进程协作模式已不能适应现代联合作战的需求.本文首先提出了一套灵活的可见性控制机制,基于可见性控制机制给出了一套新的协作进程建模框架,在该框架中各协作方从自身视角出发分别构建独立的协作进程,并支持系统加入退出时协作伙伴的自主选择及协作进程的扩展.论文同时给出了协作进程建模框架的数学形式化描述及相关算法.

关键词：联合作战系统互操作跨组织进程可见性控制机制协作进程建模框架