• 제목/요약/키워드: Multiple Connection

검색결과 471건 처리시간 0.03초

멀티홈 모바일 호스트상에서 스트라이핑 전송계층 연결을 위한 적응형 버퍼튜닝기법 (An Adaptive Buffer Tuning Mechanism for striped transport layer connection on multi-homed mobile host)

  • 파라즈;허의남
    • 인터넷정보학회논문지
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    • 제10권4호
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    • pp.199-211
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    • 2009
  • 최근 무선네트워크 기술은 이동 응용프로그램을 위해 이종통신망 연결패스 상에서 병렬로 스트라이핑 데이터 기술을 이용해 고속 데이터를 전달을 가능케 한다 [2]. 전통적으로 대역폭지연프로덕트(BDP) 기반에서 고속전송은 송신자 측에서 다중 TCP 소켓의 튜닝을 요구한다. 더욱이, 메모리와 네트워크 요구의 균형을 유지하는 ATBT같은 기술은 유선기반의 단일 소켓상에서 하나의 플로우만 가정하여 설계되었다. 그러므로 본 논문은 여러 무선 패스를 경유하는 이종 무선네트워크 상에서 고속전송을 가능케하는 스트라이핑 전송기술에 적합한 버퍼튜닝 기술을 제안한다. 제안 기술은 이동성, 링크손실, 대역폭변동성 등의 특징을 지닌 무선 멀티홈 모바일 호스트상에서 작동하는 전송계층에서의 자원관리기술이다. 실험을 통하여 유선기반의 ATBT를 본 환경에 적용한 것보다 메모리, 평균 전송량에 있어 제안 기술의 성능이 우수하다.

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Metabolic Activation of Ester- and Amide-Type Drugs by Carboxylesterases

  • Satoh, Tetsuo
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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    • pp.71-71
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    • 1993
  • Carboxylesterase is widely distributed in the tissues of vertebrates, insects, plants and mycobacteria. Among various tissues of animals and humans, the highest esterase activity with various substrates is found in the liver. Kidney has moderate carboxylesterase activity in the proximal tubules. Considerable esterase activity is also found in the small intestine epithet elial cells and serum of mammals. Besides these tissues, carboxylesterase has been found in the lung, testis, adipose tissue, nasal mucosa and even in the central nervous system. Hepatic microsomal carboxylesterase catalyzes the hydrolysis of a wide variety of endogenous and exogenous compounds such as carboxylester, thioester and aromatic amide. Since carboxylesterases are important for metabolic activation of prodrugs and detoxification of xenobiotics, differences in substrate specificity and immunological properties of this enzyme are important in connection with choosing a suitable laboratory animal for the evaluation of biotransformation and toxicity of drugs. On the other hand, liver, kidney, intestine and serum were found to contain multiple forms of carboxylesterases in animal species and humans. In fact, we have purified more than fifteen isoforms of carboxylesterases from microsomes of liver, kidney and intestinal mucosa of nine animal species and humans. and characteristics of these isoforms were compared each other in terms of their physical and immunochemical properties. On the other hand, we have reported that hepatic microsomal carboxylesterases are induced by many exogenous compounds such as phenobarbital, polycyclic aromatic hydrocarbons, Aroclor 1254, aminopyrine and clofibrate. Later, we showed that some isoforms of hepatic carboxylesterase were induced by glucocorticoids such as dexamethasone and 16 ${\alpha}$-carbonitrile, but other isoforms were rather inhibited by these compounds. These findings indicate that involvement of carboxylesterases in the metabolism and toxicity of drugs should be explained by the isoforms involved. Since 1991, we have carried out detailed research investigating the types of carboxylesterases involved in the metabolic activation of CPT-11, a derivative of camptothecin, to the active metabolite, SN-38. The results obtained strongly suggest that some isoforms of carboxylesterase of liver microsomes and intestinal mucosal membrane are exclusively involved in CPT-11 metabolism. In this symposium, the properties of carboxylesterase isoforms purified from liver, kidney and intestine of animal species and humans are outlined. In addition, metabolism of CPT-11, a novel antitumor agent, by carboxylesterases in relation to the effectiveness will also be discussed.

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중년여성의 체성분이 체력에 미치는 영향에 관한 연구 (Research on the Influence Middle-Aged woman's Body Composition Affects Physical Fitness)

  • 이상윤;김용권
    • 대한물리치료과학회지
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    • 제10권1호
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    • pp.140-148
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    • 2003
  • This study examined the relationship between body fitness and body composition as well as the body fluid and intracellular fluid (ICF) of extremities to determine body composition's quantitative criteria for body fitness. Multiple-frequency segmental bioelectrical impedance analysis and the physical fitness test provided by the Ministry of Education, Culture, Sports, Science and Technology were used to measure body composition and physical fitness, respectively. The test results showed that in women in their fifties, the correlation between the amount of body fluid in the upper limbs and grip strength was r=.654 (p<0.01) for the right arm and r=.445 for the left while that between the amount of ICF in the upper limbs and grip strength was r=.708 (p<0.01) for the right and r=.323 for the left. Also, in women in their fifties, the correlation between the amount of body fluid in the lower limbs and the result of a repetitive side jump test was r=.730 for the right leg and r=.753 for the left (p<0.01 for both), and that between the amount of ICF and the counts for the right and left legs was even higher with r=.742 and r=.763, respectively (p<0.01 for both). The body fluid and ICF volumes in the right extremities exceeded those in the left, and physical fitness was correlated with both body fluid and ICF. These findings indicate a connection between physical fitness and body fluid and ICF, suggesting that body composition may help predict physical fitness.

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저소득층 노인의 의치만족도에 영향을 미치는 요인 (The influencing factors of denture satisfaction in the low income elderly people)

  • 이지희;조미향;문덕환
    • 한국치위생학회지
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    • 제15권1호
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    • pp.73-79
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    • 2015
  • Objectives: The purpose of this study was to investigate the factors influencing on the denture satisfaction in the low income elderly people. Methods: The subjects were 143 elderly people from 60 to 75 years old wearing dentures and receiving consistent follow-up in the public health center in Busan. A self-reported questionnaire was filled out by the elderly people from February 1 to March 1, 2013. The questionnaire consisted of denture satisfaction, social variables, and psychological variables. Data were analyzed by ANOVA and multiple regression analysis using SPSS 18.0. The sociodemographic characteristics included gender, age, and chronic diseases. The recognition of oral health included pronunciation, denture maintenance, mastication ability, and education for denture care. The questionnaire was measured by Likert 5 scale. Results: Gender, chronic disease, denture care instructions, and the self-preception of the oral health after denture treatment were closely correlated with denture satisfaction(p<0.001). Age and the number of repairs were very important factor to denture satisfaction(p<0.05). Elderly women were more satisfied with denture than men and those who had no chronic diseases tended to be more satisfied with denture. Those who received oral care instructions were more satisfied with the denture than those who did not. The younger age group and no repairing prosthetic group tended to be more satisfied with the denture. Conclusions: It is important to provide the denture management services to the low income elderly when they demand the services. The national dental health policy must be focused on connection of the elderly people denture services with the public health center.

Realistic and Efficient Radio Propagation Model for V2X Communications

  • Khokhar, Rashid Hafeez;Zia, Tanveer;Ghafoor, Kayhan Zrar;Lloret, Jaime;Shiraz, Muhammad
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권8호
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    • pp.1933-1954
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    • 2013
  • Multiple wireless devices are being widely deployed in Intelligent Transportation System (ITS) services on the road to establish end-to-end connection between vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) networks. Vehicular ad hoc networks (VANETs) play an important role in supporting V2V and V2I communications (also called V2X communications) in a variety of urban environments with distinct topological characteristics. In fact, obstacles such as big buildings, moving vehicles, trees, advertisement boards, traffic lights, etc. may block the radio signals in V2X communications. Their impact has been neglected in VANET research. In this paper, we present a realistic and efficient radio propagation model to handle different sizes of static and moving obstacles for V2X communications. In the proposed model, buildings and large moving vehicles are modeled as static and moving obstacles, and taken into account their impact on the packet reception rate, Line-of-sight (LOS) obstruction, and received signal power. We use unsymmetrical city map which has many dead-end roads and open faces. Each dead-end road and open faces are joined to the nearest edge making a polygon to model realistic obstacles. The simulation results of proposed model demonstrates better performance compared to some existing models, that shows proposed model can reflect more realistic simulation environments.

대학의 강의평가 서비스에 대한 연구 (A Study for Lecture Evaluation Service in University)

  • 이문구
    • 서비스연구
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    • 제1권1호
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    • pp.91-101
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    • 2011
  • 강의평가는 정확하게 학생들의 수준을 평가하고 대학교육의 교육방법 개선을 위한 중요한 요소이다. 그러므로 본 논문은 보다 객관적이고 공정한 강의평가가 이루어질 수 있도록 강의평가 서비스에 대한 연구를 하였다. 연구 방법은 K 대학에서 시행된 강의평가를 기반으로 각 교과목별로 분석하였다. 분석 결과는 다음과 같은 결론을 도출하였다. 첫째, 수업에 4주 이상 장기결석한 학생은 강의평가에 참여할 수 없도록 한다. 둘째, 공정한 강의평가를 위하여 평가 시점을 다음 학기 수강신청이 이루어지는 시기로 한다. 셋째, 수강 신청한 학생 수와 강의평가와의 연계성을 고려한다. 넷째, 다양한 강의평가 도구유형을 적용하고, 강의평가 기술방법도 객관식과 주관식 등 다양한 평가방법을 적용한다. 마지막으로 강의평가 결과는 반드시 다음 강의에 반영될 수 있도록 한다.

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가상공간지도 기반의 3차원 가상공간 저작도구의 개발 (The Development of Authoring Tool for 3D Virtual Space Based on a Virtual Space Map)

  • 정일홍;김은지
    • 한국컴퓨터정보학회논문지
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    • 제11권2호
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    • pp.177-186
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    • 2006
  • 이 논문은 입력 영상에 대해 기존의 영상기반 렌더링 기법을 적용하고 가상공간지도라는 개념을 도입하여 사실적인 3차원 가상공간을 구축할 수 있는 효율적인 저작도구 개발에 대한 연구를 기술하고 있다. TIP 같은 기존의 기법들은 단일 영상을 사용하여 작은 3D가상공간을 구축하는 반면 여기서 제안하는 저작도구는 복수의 영상을 사용하여 광범위한 가상공간을 구축한다. 이 저작도구는 입력영상 각각에 대해 작은 3차원 가상공간을 구축하고 먼저 정의된 가상공간지도를 사용하여 이 독립적인 3D가상공간을 서로 연결하여 광범위한 3D가상공간을 구축할 수 있게 설계되었다. 가상공간지도는 세 가지 구성요소와 세 가지 방향으로 구성되어있다. 세 가지 구성요소는 특정 공간, 연결점 및 통로이고, 세 가지 방향은 정방향, 역방향 및 양방향이다. 가상공간지도는 가상공간의 연결구조, 네비게이션 정보 등 다양한 정보를 가지고 있다. 또한 이 저작도구는 사용자가 광범위한 3차원 가상공간을 쉽게 구축할 수 있게끔 사용자 인터페이스를 제공하고 있다.

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이동 에이전트 기반 전자 상거래 모형 시스템의 설계 및 구현 (Design and Implementation of Electronic Commerce Prototype System based on Mobile Agent)

  • 김평중;윤석환
    • 정보처리학회논문지B
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    • 제8B권6호
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    • pp.633-640
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    • 2001
  • 이동 에이전트는 네트워크로 연결된 컴퓨터들을 사용자를 대신하여 작업을 수행하며 이동위치를 스스로 결정할 수 있는 자율성(autonomy)과 이동성(mobility)을 가진 소프트웨어 프로그램이다. 이동 에이전트는 네트워크 연결을 계속 유지한 상태로 작업하지 않고 실행 코드와 상태가 시스템간을 이동하며 임무를 수행할 수 있기 때문에 네트워크 연결이 불안정한 무선 망 환경이나 부하가 많이 걸리는 환경에서 활용될 수 있다. 본 논문에서는 이동 에이전트 패러다임을 사용함으로써 이동 컴퓨팅 환경에서 상품 검색 및 매매를 효율적으로 수행할 수 있는 전자상거래 시스템을 구축할 수 있음을 보여주고 있다. 사용자를 대신하여 복수 개의 이동 에이전트들이 시장으로 직접 이동하여 서비스나 상품을 자율적으로 협상하거나 매매하고, 매매결과는 에이전트 실행 코드와 함께 출발지 시스템으로 이동하여 보고한다. 따라서, 우리는 이동 마켓 시스템을 설계하고 시범 구현함으로써 이동 에이전트 패러다임이 이동 컴퓨팅 환경에서 전자상거래 시스템 구축에 적합함을 보인다.

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MicroRNA Regulation in Systemic Lupus Erythematosus Pathogenesis

  • Yan, Sheng;Yim, Lok Yan;Lu, Liwei;Lau, Chak Sing;Chan, Vera Sau-Fong
    • IMMUNE NETWORK
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    • 제14권3호
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    • pp.138-148
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    • 2014
  • MicroRNAs (miRNAs) are endogenous small RNA molecules best known for their function in post-transcriptional gene regulation. Immunologically, miRNA regulates the differentiation and function of immune cells and its malfunction contributes to the development of various autoimmune diseases including systemic lupus erythematosus (SLE). Over the last decade, accumulating researches provide evidence for the connection between dysregulated miRNA network and autoimmunity. Interruption of miRNA biogenesis machinery contributes to the abnormal T and B cell development and particularly a reduced suppressive function of regulatory T cells, leading to systemic autoimmune diseases. Additionally, multiple factors under autoimmune conditions interfere with miRNA generation via key miRNA processing enzymes, thus further skewing the miRNA expression profile. Indeed, several independent miRNA profiling studies reported significant differences between SLE patients and healthy controls. Despite the lack of a consistent expression pattern on individual dysregulated miRNAs in SLE among these studies, the aberrant expression of distinct groups of miRNAs causes overlapping functional outcomes including perturbed type I interferon signalling cascade, DNA hypomethylation and hyperactivation of T and B cells. The impact of specific miRNA-mediated regulation on function of major immune cells in lupus is also discussed. Although research on the clinical application of miRNAs is still immature, through an integrated approach with advances in next generation sequencing, novel tools in bioinformatics database analysis and new in vitro and in vivo models for functional evaluation, the diagnostic and therapeutic potentials of miRNAs may bring to fruition in the future.

IT역량과 조직성과의 영향관계에서 IS 전략적 활용의 매개효과분석 (Mediating Effect of Strategic Use of Information Systems in the Relationship of IT Competency and Organizational Performance)

  • 최상민;문태수
    • 한국정보시스템학회지:정보시스템연구
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    • 제23권2호
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    • pp.67-90
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    • 2014
  • Today, the company is trying to improve for business performance through the optimization of corporate resources. Most companies set up new strategy for obtaining competitive advantage for survival in rapid changes of the global business environment. IT has an important role to reduce cost and to increases business performance such as increasing sales, improving business skills and corporate image, etc. in the corporate environment. The development and use of IT resource is recognized as essential in connection with the business strategy. Most companies tried to establish the strategic use of information systems to gain competitive advantage. IT resource management is not clear in a tangible result of the business. The purpose of this study is to find out the relationship between IT competency and organizational performance through the mediating effect of strategic use of IS. IT competency consists of IT human resource, IT infrastructure, and IT vendor management. In direct relationship between three IT competence factors and organizational performance, the results of multiple regression analysis showed that IT human resource and IT vendor management are important determinants to influence organizational performance. The additional analysis for mediating effect of strategic use of IS showed that it has mediated the relationship between IT competency factors and organizational performance. This results give us an implication, not only the importance of IT competency development, but also the importance of strategic alignment of strategic use of IS with business strategy.