• 제목/요약/키워드: Guan

검색결과 616건 처리시간 0.027초

Reproducing kernel based evaluation of incompatibility tensor in field theory of plasticity

  • Aoyagi, Y.;Hasebe, T.;Guan, P.C.;Chen, J.S.
    • Interaction and multiscale mechanics
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    • 제1권4호
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    • pp.423-435
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    • 2008
  • This paper employs the reproducing kernel (RK) approximation for evaluation of field theory-based incompatibility tensor in a polycrystalline plasticity simulation. The modulation patterns, which is interpreted as mimicking geometrical-type dislocation substructures, are obtained based on the proposed method. Comparisons are made using FEM and RK based approximation methods among different support sizes and other evaluation conditions of the strain gradients. It is demonstrated that the evolution of the modulation patterns needs to be accurately calculated at each time step to yield a correct physical interpretation. The effect of the higher order strain derivative processing zone on the predicted modulation patterns is also discussed.

Autophagy in Tumorigenesis and Cancer Treatment

  • Xu, Dong-Wei;Zhang, Guan-Qing;Wang, Zong-Wei;Xu, Xiao-Yin;Liu, Tong-Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권6호
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    • pp.2167-2175
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    • 2015
  • Autophagy is a self-digestion process, wrapping cytoplasmic proteins or organelles to form vesicles for degradation in lysosomes. The process plays an important role in the maintenance of intracellular homostasis. Here we overview articles on autophagy and cancer/tumors in Pubmed and found 327 articles. Autophagy exists in many tumors and is involved in cell malignant transformation and tumor cell growth. In early phases of tumorigenesis, autophagy clears the abnormally folded proteins and dysfunctional organelles such as mitochondria. Autophagy can also inhibit cell stress responses and prevent genetic damage. When a tumor develops, autophagy helps tumor cells survive nutritional deficiencies and hypoxic conditions. Studies of autophagy in the occurrence and progression of tumors should provide new therapeutic strategies for tumors.

Antioxidant, Antidiabetic and Cytotoxic Effects of Eucommia ulmoides Oliv. Bark in vitro

  • Qu, Guan-Zheng;Lee, Sung-Hyun;Wang, Myeong-Hyeon
    • Journal of Applied Biological Chemistry
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    • 제49권4호
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    • pp.140-142
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    • 2006
  • The aim of this study is to investigate in vitro biological properties of Eucommia ulmoides Oliv. bark. Ethyl acetate(EtOAc) fraction from aqueous extract of Eucommia bark showed strong antioxidant activity of $IC_{50}$ 19.2 ${\mu}g/ml$ by 1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical-scavenging assay. The Eucommia bark extract showed $\alpha$-glucosidase inhibitory activity and inhibited growth of human liver cancer cell, suggesting its potential biological value of anticancer.

Isozyme Analysis and Relationships Among Three Species in Malaysian Trichoderma Isolates

  • Siddiquee, Shafiquzzaman;Tan, Soon-Guan;Yusof, Umi-Kalsom
    • Journal of Microbiology and Biotechnology
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    • 제20권9호
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    • pp.1266-1275
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    • 2010
  • Isozyme and protein electrophoresis data from mycelial extracts of 27 isolates of Trichoderma harzianum, 10 isolates of T. aureoviride, and 10 isolates of T. longibrachiatum from Southern Peninsular Malaysia were investigated. The eight enzyme and a single protein pattern systems were analyzed. Three isozyme and total protein patterns were shown to be useful for the detection of three Trichoderma species. The isozyme and protein data were analyzed using the Nei and Li Dice similarity coefficient for pairwise comparison between individual isolates, species isolate group, and for generating a distance matrix. The UPGMA cluster analysis showed a higher degree of relationship between T. harzianum and T. aureoviride than to T. longibrachiatum. These results suggested that the T. harzianum isolates had high levels of genetic variation compared with the other isolates of Trichoderma species.

IEC 61850을 이용한 새로운 결합 극복형 시스템 응용 (The application of IEC61850 in a new anti-fault substation system)

  • 관창;한승수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.242-243
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    • 2006
  • The compatibility between different automation devices hasn't been difficult any longer while the new standard IEC61850 is imposed which provides efficient implementation on both embedded and non-embedded system. While implementing the substation automation, different devices from different company may be an obstacle to system designing. However, with the help of IEC61850 this problem can be neglected. In this paper the newest development of the demo system based on IEC61850 will be introduced.

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변전소 IED의 보안과 신뢰성에 관한 고찰 (Analysis On Security and Dependability for IED System in SAS)

  • 관창;한승수;이승재
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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    • pp.21-23
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    • 2006
  • As a general rule for evaluating dependability of a system, reliability is commonly considered which barely rays attention to the system behavior, however the estimation is based on the assumption of a fault-frost system, which may be impracticable and inaccurate especially for complicated system. This paper introduces a security and dependability integrated approach to analyze the availability of a fault-active system both from dependability and security points of view. Two fault modes involved are discussed about the impairment to the system reliance. The approach can be well applied to estimate and quantify the attribute of system robustness with the help of Markov chain process, which is good at solving status related problem. The comparison result between dual system and IEC61850-based almighty backup system is shown to sup-port the suggested approach.

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양방향 전력전달이 가능한 전압형 QZSI를 이용한 유도 전동기 시스템 (Induction Motor Drive System Using Bi-directional QZSI)

  • 한상협;김흥근;구본관;차헌녕;전태원;노의철
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2014년도 추계학술대회 논문집
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    • pp.35-36
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    • 2014
  • 양방향 QZSI(Quasi Z-Source Inverter)를 이용한 유도전동기 제어 시스템은 암단락 상태를 제어에 이용할 수 있어서 추가 컨버터 없이도 단일 구조로 가변 배터리 전압을 일정하게 승압할 수 있다. 암단락을 이용한 승압은 직류단 전압제어가 보장되어야 하며 전압 제어기 성능이 인버터 출력 전류 제어에 상당한 영향을 미친다. 전압제어는 임피던스 네트워크의 커패시터 전압을 일정하게 제어하거나 직류단 전압을 직접적으로 또는 간접적으로 일정하도록 제어하여 구현할 수 있다. 본 논문에서 양방향 전력 전달이 가능한 QZSI를 통해 유도 전동기를 제어하며 시뮬레이션과 실험을 통해 이를 검증한다.

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Data Clustering Using Hybrid Neural Network

  • Guan, Donghai;Gavrilov, Andrey;Yuan, Weiwei;Lee, Sung-Young;Lee, Young-Koo
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2007년도 춘계학술발표대회
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    • pp.457-458
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    • 2007
  • Clustering plays an indispensable role for data analysis. Many clustering algorithms have been developed. However, most of them suffer poor performance of learning. To archive good clustering performance, we develop a hybrid neural network model. It is the combination of Multi-Layer Perceptron (MLP) and Adaptive Resonance Theory 2 (ART2). It inherits two distinct advantages of stability and plasticity from ART2. Meanwhile, by combining the merits of MLP, it improves the performance for clustering. Experiment results show that our model can be used for clustering with promising performance.

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Threshold Setting for LOS/NLOS Identification Based on Joint TOA and RSS

  • Guan, XuFeng;Hur, SooJung;Park, Yongwan
    • 대한임베디드공학회논문지
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    • 제5권3호
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    • pp.152-156
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    • 2010
  • Non-line-of-sight (NLOS) propagation is one of the challenges in radio positioning. Distinguishing the transmission status of the communication as line-of-sight (LOS) or NLOS is of great importance for the wireless communication systems. This paper focuses on the identification of NLOS based on time-of-arrival (TOA) distance estimates and the received signal strength (RSS) measurements. We set a path loss threshold based on the joint TOA and RSS based NLOS detection method to determine LOS or NLOS. Simulation results show that the proposed method ensures the correct of detection for the LOS condition and can improve the NLOS identification for the weak noise and long distance.

Layered finite element method in cracking and failure analysis of RC beams and beam-column-slab connections

  • Guan, Hong;Loo, Yew-Chaye
    • Structural Engineering and Mechanics
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    • 제5권5호
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    • pp.645-662
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    • 1997
  • A nonlinear semi-three-dimensional layered finite element procedure is developed for cracking and failure analysis of reinforced concrete beams and the spandrel beam-column-slab connections of flat plates. The layered element approach takes the elasto-plastic failure behaviour and geometric nonlinearity into consideration. A strain-hardening plasticity concrete model and a smeared steel model are incorporated into the layered element formulation. Further, shear failure, transverse reinforcement, spandrel beams and columns are successfully modelled. The proposed method incorporating the nonlinear constitutive models for concrete and steel is implemented in a finite element program. Test specimens including a series of reinforced concrete beams and beam-column-slab connections of flat plates are analysed. Results confirm the effectiveness and accuracy of the layered procedure in predicting both flexural and shear cracking up to failure.