RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
        • 등재정보
        • 학술지명
          펼치기
        • 주제분류
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • Optimization of Distribution Network with Distributed Generation Based on an Improved Genetic Algorithm

        Xiaoyu Sun,Jinsong Liu,Xin Sun,Jingwei Hu 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.1

        The system of distribution network with distributed generation is analyzed, and dynamic optimization based on an improved genetic algorithm is presented in this paper. First, the mathematical model of distribution network can be established by using constraints and objective function, which contains the network loss, the DGs investment and reliability of power supply. Then, according the construction of distribution network, this paper presents a design of improved genetic algorithm. Finally, IEEE 14 nodes system is adopted to realize the design of the algorithm.

      • The Improved Neural Network Algorithm of License Plate Recognition

        Jingwei Dong,Meiting Sun,Gengrui Liang,Kui Jin 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.5

        With high definition cameras are widely used in urban traffic monitoring, the resolution of vehicle and traffic monitoring image rises. As the main component of intelligent traffic system, the vehicle license plate recognition technique faces new challenges and some new demands are put forward. Aiming at the problems of cutting down the time delay and eliminating characters outside of vehicle license plate, a set of license plate recognition algorithm is developed in this paper. The process of recognition in this paper is divided into four parts: image preprocessing, license plate location, license plate segmentation and character recognition. In license plate location, an accelerating matching method based on particle image correlation method is employed. In character recognition, an improved BP neural network algorithm is employed. The principle, procedure and simulation of the algorithm is described in details. High definition images with 2 mega pixels are used as the input of simulation.

      • KCI등재

        Sliding Mode Control for We-energy Based on Markovian Jumping Systems

        Jingwei Hu,Qiuye Sun,Yan Zhao,Jie Hu 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.7

        Sliding mode control (SMC) is a promising robust control approach for the abrupt variations in complexsystem. Energy internet (EI), as a dynamic nonlinear strong coupling system, has different operating states underdifferent operating conditions (system connection, load levels and faults, etc.). We-Energy (WE), as a basic energyunit in EI, is proposed for describing the essential characteristics and operating state of EI. According the operatingstates of EI, four operating modes of WE presented in this paper can be randomly converted, which correspond thestochastic markov process. Then, based on the coupling characteristics of EI, a set of state equations is establishedto embody the markovian jumping system (MJS) of WE. Moreover, sliding surface and contorl scheme for WEbased on MJS is designed. Finally, a numerical simulation is shown to illustrate the proposed method.

      • KCI등재

        Characterization and performance test of phenolphthalein poly(aryl ether ketone) fractionated by incremental poor solvent fractionation

        Zengxu Qian,Jingwei Jiang,Yunlong Sun,Qiliang Yuan,Zhichao Wang,Zhipeng Wang,Guangyuan Zhou 한국고분자학회 2023 Macromolecular Research Vol.31 No.8

        Though phenolphthalein poly(aryl ether ketone) (PEK-C) has gained attention as a special engineering plastic materials by virtue of its good thermal stability and favorable mechanical properties, its applications are limited due to its wide PDI during polymerization, which result in poor mechanical properties of PEK-C. In order to investigate the effect of molecular weight and polydispersity index (PDI) on PEK-C, an incremental poor solvent fractionation method was used to fractionate PEK-C. The process produced a series of grades with decreasing molecular weight and PDI. The LCP (linear cloud point) equation was combined with the grading method to find the optimal PEK-C/DMAc/ Non-solvent additives (NSA) system, which can be used to improve the grading efficiency. The obtained results showed that the incremental poor solvent fractionation method with the PEK-C/DMAc/EA system made the molecular weight distributed in the range of 25 ~ 113 kDa, PDI mostly distributed in the range of 1.1 ~ 1.4, and the narrowest PDI to reach 1.13, which could not be obtained through the condensation reaction. Meanwhile, we can also achieve expanded production. By fractionation, the elastic modulus of PEK-C film could be increased by up to 22.6%, elongation at break by up to 38.3%, the fracture strength by up to 38.2%, and impact strength of the sheest by up to 41.2%, while the polymer still maintained good thermal and UV shielding properties. This unique Polymer/Solution/NSA system can yield an effective design strategy for controlling its molecular weight and PDI and improving its mechanical performance.

      • KCI등재

        Analysis of Localized Surface Plasmon Resonance in Ag/ITO/CdS/SiO2 Multilayered Nanostructured Composite

        Chao Liu,Jingwei Lv,Famei Wang,Qiang Liu,Haiwei Mu,Tao Sun,Qiang Liu,Paul K. Chu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.8

        Multilayered nanoshells have attracted much attention due to their unique optical, electronic and magnetic properties. In this work, numerical calculation using discrete dipole approximation (DDA) is conducted to investigate the quad-layered metal nanoshell consisting of a particle with a dielectric silica (SiO2) core, inner cadium sulfide (CdS) shell, middle indium tin oxide (ITO) shell and outer metal silver (Ag) shell. The phenomenon is interpreted by plasmon hybridization theory and the Ag–ITO–CdS–SiO2 multilayered nanoshells are studied by extinction spectra of localized surface plasmon resonance. The variation in the spectrum peak with nanoparticle thickness and refractive index of the surrounding medium is derived. The electric field enhancement contour around the nanoparticles under illumination is analyzed at the plasmon resonance wavelength. The |ω-->, |ω+->, and |ω-+> modes red-shift with the refractive index of the surrounding medium and increase in the layer thickness causes either blue-shift or red-shift as shown by the extinction spectra. The mechanism of the red-shift or blue-shift is discussed. The |ω--> blue-shifts and furthermore, the |ω-+> and |ω+-> modes of the Ag coated multilayered nanostructure are noticeable by comparing the extinction efficiency spectra of the Au–ITO–CdS–SiO2 and Ag–ITO–CdS–SiO2 multilayered nanoshells.

      • KCI등재

        Analysis of Local Surface Plasmon Resonance in Multilayered Au/Ag/Graphene Nanoshells

        Chao Liu,Zhaoting Liu,Jingwei Lv,Tao Sun,Qiang Liu,Haiwei Mu,Paul K. Chu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.5

        "The localized surface plasmon resonance (LSPR) properties of Au/Ag/graphene nanoshells are studied by discrete dipole approximation (DDA). The coupled resonance wavelengths show a remarkable dependence on the graphene thickness as well as refractive index of the surrounding medium. The resonance wavelengths of Au/Ag/graphene nanoshells red-shift as the thickness of the graphene layer is increased, when the radii of the Au core and Ag interlayer are 40 nm and 45nm, respectively. Specifically, the longer wavelength red-shifts from 540 nm to 740 nm when the refractive index varies from 1.25 to 2.05. "

      • KCI등재

        Performance of Contra-Rotating Propellers for Stratospheric Airships

        Zhihao Tang,Peiqing Liu,Jingwei Sun,Yaxi Chen,Hao Guo,Guangchao Li 한국항공우주학회 2015 International Journal of Aeronautical and Space Sc Vol.16 No.4

        Small advance ratio and low Reynolds number of stratospheric propulsion system bring lots of challenges to the design of propellers. Contra-rotating propeller configuration is proposed to improve the propulsion efficiency. In this paper, the feasibility of contra-rotating propeller for stratospheric airship has been assessed and its performance has been investigated by wind tunnel tests. The experimental results indicate, at relatively low Reynolds number, although the advance ratio is fixed, the performance of propellers is different with variation of Reynolds number. Moreover, at the same Reynolds number, the efficiency of contra-rotating propeller achieved appears to be a few percent greater than that for a standard conventional propulsion system. It can be concluded that contra-rotating propellers would be an efficient means to improve the performance of stratospheric airship propulsion system.

      • SCIESCOPUSKCI등재

        Performance of Contra-Rotating Propellers for Stratospheric Airships

        Tang, Zhihao,Liu, Peiqing,Sun, Jingwei,Chen, Yaxi,Guo, Hao,Li, Guangchao The Korean Society for Aeronautical and Space Scie 2015 International Journal of Aeronautical and Space Sc Vol.16 No.4

        Small advance ratio and low Reynolds number of stratospheric propulsion system bring lots of challenges to the design of propellers. Contra-rotating propeller configuration is proposed to improve the propulsion efficiency. In this paper, the feasibility of contra-rotating propeller for stratospheric airship has been assessed and its performance has been investigated by wind tunnel tests. The experimental results indicate, at relatively low Reynolds number, although the advance ratio is fixed, the performance of propellers is different with variation of Reynolds number. Moreover, at the same Reynolds number, the efficiency of contra-rotating propeller achieved appears to be a few percent greater than that for a standard conventional propulsion system. It can be concluded that contra-rotating propellers would be an efficient means to improve the performance of stratospheric airship propulsion system.

      • KCI등재

        Characterization of clutch traits and egg production in six chicken breeds

        Shi Lei,Li Yunlei,Isa Adam Mani,Ma Hui,Yuan Jingwei,Wang Panlin,Ge Pingzhuang,Gong Yanzhang,Chen Jilan,Sun Yanyan 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.6

        Objective: The better understanding of laying pattern of birds is crucial for developing breed-specific proper breeding scheme and management. Methods: Daily egg production until 50 wk of age of six chicken breeds including one layer (White Leghorn, WL), three dual-purpose (Rhode Island Red, RIR; Columbian Plymouth Rock, CR; and Barred Plymouth Rock, BR), one synthetic dwarf (DY), and one indigenous (Beijing-You Chicken, BYC) were used to characterize their clutch traits and egg production. The age at first egg, egg number, average and maximum clutch length, pause length, and number of clutches and pauses were calculated accordingly. Results: The egg number and average clutch length in WL, RIR, CR, and BR were higher than those in DY and BYC (p<0.01). The numbers of clutches and pauses, and pause length in WL, RIR, CR, and BR were lower than those in DY and BYC (p<0.01). The coefficient variations of clutch length in WL, RIR, CR, and BR (57.66%, 66.49%, 64.22%, and 55.35%, respectively) were higher than DY (41.84%) and BYC (36.29%), while the coefficient variations of egg number in WL, RIR, CR, and BR (9.10%, 9.97%, 10.82%, and 9.92%) were lower than DY (15.84%) and BYC (16.85%). The clutch length was positively correlated with egg number (r = 0.51 to 0.66; p<0.01), but not correlated with age at first egg in all breeds. Conclusion: The six breeds showed significant different clutch and egg production traits. Due to the selection history, the high and median productive layer breeds had higher clutch length than those of the less productive indigenous BYC. The clutch length is a proper selection criterion for further progress in egg production. The age at first egg, which is independent of clutch traits, is especially encouraged to be improved by selection in the BYC breed.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼