• Title/Summary/Keyword: Deficiencies

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Behavior of damaged and undamaged concrete strengthened by carbon fiber composite sheets

  • Ilki, Alper;Kumbasar, Nahit
    • Structural Engineering and Mechanics
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    • v.13 no.1
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    • pp.75-90
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    • 2002
  • Many existing concrete structures suffer from low quality of concrete and inadequate confinement reinforcement. These deficiencies cause low strength and ductility. Wrapping concrete by carbon fiber reinforced polymer (CFRP) composite sheets enhances compressive strength and deformability. In this study, the effects of the thickness of the CFRP composite wraps on the behavior of concrete are investigated experimentally. Both monotonic and repeated compressive loads are considered during the tests, which are carried out on strengthened undamaged specimens, as well as the specimens, which were tested and damaged priorly and strengthened after repairing. The experimental data shows that, external confinement of concrete by CFRP composite sheets improves both compressive strength and deformability of concrete significantly as a function of the thickness of the CFRP composite wraps around concrete. Empirical equations are also proposed for compressive strength and ultimate axial deformation of FRP composite wrapped concrete. Test results available in the literature, as well as the experimental results presented in this paper, are compared with the analytical results predicted by the proposed equations.

A Study on the Development of Inspection Module for Port State Control (항만국통제 검사 모듈 개발에 관한 연구)

  • 이은방;이인수
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.6 no.2
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    • pp.17-31
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    • 2000
  • Port State Control(PSC) plays important roles in ensuring the ship' safety as well as preserving the marine environment in port and coastal sea. The effect of PSC carried out according to the procedure and document offered by Tokyo MOU depends greatly on inspector and inspection technique. So, it is very important to inspect ships impartially with advanced method. In the case of Korea, the only 30 percent of ships with deficiencies visited to ports are inspected due to the lack of PSC inspectors. So new inspection technique and module are required in order to improve inspection efficiency and to resolve problems mentioned. In this paper, we introduce a module for PSC inspection and evaluate it by inspecting 10 model ships and comparing with present method. The proposed module is expected to obtain the objectivity of inspection, to offer inspection guideline and to determine the priority of inspection ships.

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Issues and Vision of Korea Maritime Police (해양경찰의 과제와 발전)

  • Sang-Jib Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.6 no.2
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    • pp.57-66
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    • 2000
  • The argument about enlarging or limiting the function of the Korea Maritime Police. Agency (KMPA) has been and will be repeated. In this paper, the author highlights the internal and external issues facing KMPA, stemming partly from deficiencies of its struggles for advancement of the organization and partly from shortcomings of political support far it. And he urges KMPA to change the organizational culture for maintaining its identity and characteristics as a lead maritime agency by practising a scientific management system for maximizing cost-effectiveness of its administrative resources. In addition, he also suggests that KMPA adopt the Total Quality Management System for quality improvements in services and greater efficiency in its organizational structure to meet the future competition in the changing political and legal environment. he concludes by providing a 6-point vision statement for KMPA from the standpoint of favoring enlarging the function of KMPA.

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Assessing Middle-income Residents' Attitudes about Their Urban High-rise Condominium in Contemporary American Society

  • Kim, Wonpil
    • Architectural research
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    • v.2 no.1
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    • pp.27-34
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    • 2000
  • Most research on high-rise housing has focused on low-income residences, and usually the psychological and social well-being of women and children. The validity of such findings are questionable for other populations since high-rise living has served other groups and their various needs in particular settings. Lack of knowledge and understanding about high-rises has represented an obstacle to the accurate representation of American urban reality in residential environments. The review of literature and factor analysis identified Important environmental factors. The survey was conducted in the selected downtown high-rise communities of major U.S. cities. Analyses revealed that there were unique characteristics of residents who prefer to live in this type of housing. It was also found that living in middle-income urban high-rise condominiums does not contribute significantly to the problems associated with high-rise living itself. Even though there were some deficiencies of social interaction and activities among residents, the middle-income condominiums were serving particular residents as maintenance-free and safe place imprinted by a positive image of sweet memories or sometimes by a window view presiding over downtown skyline.

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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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    • v.16 no.6
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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.

The Role of Allograft for Posterior Cruciate Ligament Reconstruction (후방 십자 인대 재건술에서 동종 이식건의 역할)

  • Chun, Churl Hong
    • Journal of the Korean Arthroscopy Society
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    • v.2 no.1
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    • pp.40-44
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    • 1998
  • The use of autogenous tissues is preferred for knee ligament reconstruction. However allografts play a role in major ligament reconstructive procedures in which multiple substitutions or revisions are required. In the dislocated knee, allografts may offer an advantage in reconstructing the PCL. But allografts in knee ligament surgery must be considered in terms of biomechanical and regenerative properties, disease transmission and immunogenecity, and methods of preservation and sterilization. Also only a few authors have described the use of allograft for reconstruction of a ruptured PCL, either a single procedure, or in combination with ACL repair following knee dislocation. Furthermore, the problems that the clinician faces with use of allografts is the necessity for supervision to ensure that the grafts are correctly processed, secondarily sterilized, and free of transmissible diseases. For these reasons, the routine use of allograft materials in the treatment of ligament deficiencies should be avoid and provide with meaningful outcome studies, including longterm follow-up.

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MEROMORPHIC SOLUTIONS OF A COMPLEX DIFFERENCE EQUATION OF MALMQUIST TYPE

  • Zhang, Ran-Ran;Huang, Zhi-Bo
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.6
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    • pp.1735-1748
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    • 2014
  • In this paper, we investigate the finite order transcendental meromorphic solutions of complex difference equation of Malmquist type $$\prod_{i=1}^{n}f(z+c_i)=R(z,f)$$, where $c_1,{\ldots},c_n{\in}\mathbb{C}{\backslash}\{0\}$, and R(z, f) is an irreducible rational function in f(z) with meromorphic coefficients. We obtain some results on deficiencies of the solutions. Using these results, we prove that the growth order of the finite order solution f(z) is 1, if f(z) has Borel exceptional values $a({\in}\mathbb{C})$ and ${\infty}$. Moreover, we give the forms of f(z).

Forecasting Model for Korean Ships' Detention in Port State Control

  • Kim, Gil-Soo;Kong, Gil-Young
    • Journal of Navigation and Port Research
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    • v.32 no.9
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    • pp.729-736
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    • 2008
  • Very often has it happened that Korean flag ships were detained due to the defect of the ship itself at the port they are entering into by the system of Port State Control(PSC). It does matter because the high detention ratio of Korean ships causes to increase the survey ratio of Korean ships by PSC countries, which increases overall operating costs of Korean shipping companies. Therefore Korean government should take tougher action on the detention of Korean ships. The study uses 946 inspections to formulate the model of identifying PSC-weak ships by logistic regression analysis.

Determination of Multicast Routing Scheme for Traffic Overload in network system (네트워크 시스템에서 트래픽 부하에 따른 멀티캣트 라우팅 방식)

  • Seul, Nam-O
    • Proceedings of the KIEE Conference
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    • 2005.07d
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    • pp.2936-2938
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    • 2005
  • The deployment of multicast communication services in the internet is expected to lead a stable packet transfer even in heavy traffic as in network system environment. The core based tree scheme among many multicast protocols is the most popular and suggested recently. However, CBT exhibit two major deficiencies such as traffic concentration or poor core placement problem. so, measuring the bottleneck link bandwidth along a path is important for understanding th performance of multicast. We propose not only a definition of CBT's core link state that Steady-State, Normal-State and Bottleneck State according to the estimation link speed rate, but also the changeover of multicast routing scheme for traffic overload. In addition, we introduce anycast routing tree, a efficient architecture for construst shard multicast trees.

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Review And Challenges In Speech Recognition (ICCAS 2005)

  • Ahmed, M.Masroor;Ahmed, Abdul Manan Bin
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1705-1709
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    • 2005
  • This paper covers review and challenges in the area of speech recognition by taking into account different classes of recognition mode. The recognition mode can be either speaker independent or speaker dependant. Size of the vocabulary and the input mode are two crucial factors for a speech recognizer. The input mode refers to continuous or isolated speech recognition system and the vocabulary size can be small less than hundred words or large less than few thousands words. This varies according to system design and objectives.[2]. The organization of the paper is: first it covers various fundamental methods of speech recognition, then it takes into account various deficiencies in the existing systems and finally it discloses the various probable application areas.

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