THE DYNAMIC OF TWO-SPECIES IMPULSIVE DELAY GILPIN-AYALA COMPETITION SYSTEM WITH PERIODIC COEFFICIENTS

Zhang, Shuwen,Tan, Dejun The Korean Society for Computational and Applied M 2011 Journal of applied mathematics & informatics Vol.29 No.5

In this paper, we consider two-species periodic Gilpin-Ayala competition system with delay and impulsive effect. By using some analysis methods, sufficient conditions for the permanence of the system are derived. Further, we give the conditions of the existence and global asymptotic stable of positive periodic solution.

THE DYNAMIC OF TWO-SPECIES IMPULSIVE DELAY GILPIN-AYALA COMPETITION SYSTEM WITH PERIODIC COEFFICIENTS

Shuwen Zhang,Dejun Tan 한국전산응용수학회 2011 Journal of applied mathematics & informatics Vol.29 No.5

In this paper, we consider two-species periodic Gilpin-Ayala competition system with delay and impulsive effect. By using some analysis methods, suffcient conditions for the permanence of the system are derived. Further, we give the conditions of the existence and global asymptotic stable of positive periodic solution

Permanence for three species predator-prey system with delayed stage-structure and impulsive perturbations on predators

Shuwen Zhang,Tejun Tan 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.5

In this paper, three species stage-structured predator-preymodel with time delayed and periodic constant impulsive perturbations of predator at fixed times is proposed and investigated. We show that the conditions for the global attractivity of prey(pest)-extinction periodic solution and permanence of the system. Our model exhibits a new modelling method which is applied to investigate impulsive delay differential equations. Our results give some reasonable suggestions for pest management. In this paper, three species stage-structured predator-preymodel with time delayed and periodic constant impulsive perturbations of predator at fixed times is proposed and investigated. We show that the conditions for the global attractivity of prey(pest)-extinction periodic solution and permanence of the system. Our model exhibits a new modelling method which is applied to investigate impulsive delay differential equations. Our results give some reasonable suggestions for pest management.

PERMANENCE FOR THREE SPECIES PREDATOR-PREY SYSTEM WITH DELAYED STAGE-STRUCTURE AND IMPULSIVE PERTURBATIONS ON PREDATORS

Zhang, Shuwen,Tan, Dejun The Korean Society for Computational and Applied M 2009 Journal of applied mathematics & informatics Vol.27 No.5

In this paper, three species stage-structured predator-prey model with time delayed and periodic constant impulsive perturbations of predator at fixed times is proposed and investigated. We show that the conditions for the global attractivity of prey(pest)-extinction periodic solution and permanence of the system. Our model exhibits a new modelling method which is applied to investigate impulsive delay differential equations. Our results give some reasonable suggestions for pest management.

부산 지하철 휴게 공간 리디자인에 대한 연구 - 대연역 생태 공간 개발 중심으로 -

장무 ( Zhang Wu ),김철수 ( Kim Chulsoo ),조수문 ( Zhao Shuwen ),양혜민 ( Yang Huimin ),장한문 ( Zhang Hanwen ) 한국공간디자인학회 2020 한국공간디자인학회논문집 Vol.15 No.8

(연구배경 및 목적) 본 연구는 부산 대연역 지하철 휴게 공간 리디자인을 통해 향후 관련 디자인에 기초적인 자료로 삼기 위함이다. 또한 부산의 기타 지하철역에 적용함으로써 부산 전체의 쾌적한 도시 건설을 유도함으로 부산의 발전을 촉진하며, 도시주민의 편의성 및 삶의 질 향상을 도모하기 위함이다. 지하 공간 개선 목적은 지상 환경을 손상하지 않는 범위 내에서 공간개발을 합리적으로 제안하는 것에 있다. 이러한 제안은 시민편의 활용, 지면 및 도시 지하 환경 개발 가치가 있다. 도는 공공장소 시설 및 장소의 보존과 같은 이유에서 출발한다. (연구방법) 연구방법은 휴게공간의 연속성과 접근가능성을 중시하고, 도시디자인 요소 방면에서는 구역경제, 생활 방식, 생태기술 등의 요소 연구에 중심을 둔다. 이 연구에서는 자연채광 시스템, 벽면녹화시스템과 음이온환기시스템 등 기술 융합을 통해서 지하 휴게 공간 리디자인을 제안하고자 한다, 지하공간의 기본방향은 ①치유 기능 ② 녹색 에너지 제어 기능 ③ 실용 기능 크게 세 가지로 구분한다. 기대하는 결과는 도시 공공 공간 부족의 문제를 대한 도시환경 문제의 해결을 도모하는 것이다. (결과) 도시 공간형태구성과 시설구성 요소적인에 따라서 도시 지하 휴게 공간 개발을 이용 목적, 휴게공간에서의 개선점 등에 대한 설문조사에서 나온 응답자의 선호와 만족여부를 토대로 살펴보기로 한다. 현재 대연역부근에 거주하는 인원은 대부분 단독주택으로 인구밀도가 상대적으로 낮은 편이나, 교통이 편리한 지역이라 부경대학교, 경성대학교, 동명대학교 유학생 대학생 등 등 학생들의 주요 자취 지역으로 선호되어 높은 밀집이다. 하지만 밀집도에 비해 휴게공간이 많이 부족한 편이다. 이러한 휴게 공간 부족 문제의 해결책으로 등장한 것이 입체적인 도시공간계획이다. (결론) 대연역 지하철 지하 휴게 공간 리디자인(재개발)을 통해서 향후 관련 디자인에 기초적인 자료로 삼을 수 있고, 또한 부산의 기타 지하철역에 적용함으로써 부산 전체의 도시 건설을 제고하고 부산의 발전을 촉진하며, 도시주민의 편리성을 제고하고 삶의 질을 좋아지는 것이다. 이를 위해 공공 공간의 연속성과 접근가능성을 중시하고, 구역경계, 생활 방식, 생태기술 등의 도시디자인 요소에 관심을 가져야 한다. (Background and Purpose) This study aimed to redesign the rest space of Busan Daeyeon subway station as the basic data for future design. It attempted to make this research applicable to other subway stations in Busan, guide Busan to build a more comfortable city, promote its development, and improve the convenience and quality of life of city dwellers. To improve the underground space requires putting forward reasonable suggestions for the development of space without damaging the ground environment. These renovations are beneficial to improve the use of underground by citizens and the value of urban underground space development. The purpose of this research is to maximize the preservation of space and facilities in public places. (Method) We emphasized the continuity and accessibility of the space for rest and focused on the elements of regional economy, lifestyle, and ecological technology in urban design. In this research, we hoped to redesign the underground rest area through technology integration, such as natural lighting system, vertical greening of walls, and negative ion ventilation system. The basic direction of underground space design was divided into (1) the healing function; (2) Green energy control function; and (3) practical function. To seek solutions to urban environmental problems and the shortage of urban public space. (Result) According to the configuration of urban space and the composition of facilities, the possibility of improvement and development of urban underground leisure space will be studied based on the survey data of the functional needs and improvement points of the respondents. At present, most of the people living near Daeyeon station are students, and the population density is relatively high. However, due to the convenient transportation, it has become the preferred residence for international students and Korean students of Pukyong National University, Kyungsung University, and Tongmyong University. However, compared to the population density, the rest space is insufficient. To solve these problems, this research used three-dimensional urban space planning. (Conclusion) Through the redesign (redevelopment) of the underground rest area of Daeyeon subway station, this research can be used as the basic data for future design, and it can be applied to other subway stations in Busan, which will enhance the urban construction of the whole Busan and promote its development. Furthermore, it improves the convenience of urban residents and improves the quality of life. Therefore, we should emphasize the continuity and accessibility of public space, and pay attention to the design elements of urban space, regional boundaries, lifestyle, ecological technology, and other urban design elements.

Genome wide association study on feed conversion ratio using imputed sequence data in chickens

Jiaying Wang,Xiaolong Yuan,Shaopan Ye,Shuwen Huang,Yingting He,Hao Zhang,Jiaqi Li,Xiquan Zhang,Zhe Zhang 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.4

Objective: Feed consumption contributes a large percentage for total production costs in the poultry industry. Detecting genes associated with feeding traits will be of benefit to improve our understanding of the molecular determinants for feed efficiency. The objective of this study was to identify candidate genes associated with feed conversion ratio (FCR) via genome-wide association study (GWAS) using sequence data imputed from single nucleotide polymorphism (SNP) panel in a Chinese indigenous chicken population. Methods: A total of 435 Chinese indigenous chickens were phenotyped for FCR and were genotyped using a 600K SNP genotyping array. Twenty-four birds were selected for sequencing, and the 600K SNP panel data were imputed to whole sequence data with the 24 birds as the reference. The GWAS were performed with GEMMA software. Results: After quality control, 8,626,020 SNPs were used for sequence based GWAS, in which ten significant genomic regions were detected to be associated with FCR. Ten candidate genes, ubiquitin specific peptidase 44, leukotriene A4 hydrolase, ETS transcription factor, R-spondin 2, inhibitor of apoptosis protein 3, sosondowah ankyrin repeat domain family member D, calmodulin regulated spectrin associated protein family member 2, zinc finger and BTB domain containing 41, potassium sodium-activated channel subfamily T member 2, and member of RAS oncogene family were annotated. Several of them were within or near the reported FCR quantitative trait loci, and others were newly reported. Conclusion: Results from this study provide valuable prior information on chicken genomic breeding programs, and potentially improve our understanding of the molecular mechanism for feeding traits.

Pore structure evolution characteristics of sandstone uranium ore during acid leaching

Sheng Zeng,Yuan Shen,Bing Sun,Ni Zhang,Shuwen Zhang,Song Feng 한국원자력학회 2021 Nuclear Engineering and Technology Vol.53 No.12

To better understand the permeability of uranium sandstone, improve the leaching rate of uranium, andexplore the change law of pore structure characteristics and blocking mechanism during leaching, wesystematically analyzed the microstructure of acid-leaching uranium sandstone. We investigated thevariable rules of pore structure characteristics based on nuclear magnetic resonance (NMR). The resultsshowed the following: (1) The uranium concentration change followed the exponential law duringuranium deposits acid leaching. After 24 h, the uranium leaching rate reached 50%. The uranium leachingslowed gradually over the next 4 days. (2) Combined with the regularity of porosity variation, Stages Iand II included chemical plugging controlled by surface reaction. Stage I was the major completion phaseof uranium displacement with saturation precipitation of calcium sulfate. Stage II mainly precipitatediron (III) oxide-hydroxide and aluminum hydroxide. Stage III involved physical clogging controlled bydiffusion. (3) In the three stages of leaching, the permeability of the leaching solution changed with thepore structure, which first decreased, then increased, and then decreased

Fractal kinetic characteristics of uranium leaching from low permeability uranium-bearing sandstone

Sheng Zeng,Yuan Shen,Bing Sun,Kaixuan Tan,Shuwen Zhang,Wenhao Ye 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.4

The pore structure of uranium-bearing sandstone is one of the critical factors that affect the uraniumleaching performance. In this article, uranium-bearing sandstone from the Yili Basin, Xinjiang, China, wastaken as the research object. The fractal characteristics of the pore structure of the uranium-bearingsandstone were studied using mercury intrusion experiments and fractal theory, and the fractaldimension of the uranium-bearing sandstone was calculated. In addition, the effect of the fractal characteristics of the pore structure of the uranium-bearing sandstone on the uranium leaching kinetics wasstudied. Then, the kinetics was analyzed using a shrinking nuclear model, and it was determined that therate of uranium leaching is mainly controlled by the diffusion reaction, and the dissolution rate constant(K) is linearly related to the pore specific surface fractal dimension (DS) and the pore volume fractaldimension (DV). Eventually, fractal kinetic models for predicting the in-situ leaching kinetics wereestablished using the unreacted shrinking core model, and the linear relationship between the fractaldimension of the sample's pore structure and the dissolution rate during the leaching was fitted.