• Title/Summary/Keyword: Connection chain

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Performance Analysis of an ATM Multiplexer with Multiple QoS VBR Traffic

  • Kim, Young-Jin;Kim, Jang-Kyung
    • ETRI Journal
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    • v.19 no.1
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    • pp.13-25
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    • 1997
  • In this paper, we propose a new queuing model, MMDP/MMDP/1/K, for an asynchronous transfer mode(ATM) multiplexer with multiple quality of service(QoS) variable bit rate (VBR) traffic in broadband-integrated services digital network (B-ISDN). We use the Markov Modulated Deterministic Process(MMDP) to approximate the actual arrival process and another MMDP for service process Using queuing analysis, we derive a formula for the cell loss probability of the ATM multiplexer in terms of the limiting probabilities of a Markov chain. The cell loss probability can be used for connection admission control in ATM multiplexer and the calculation of equivalent bandwidth for arrival traffic, The major advantages of this approach are simplicity in analysis, accuracy of analysis by comparison of simulation, and numerical stability.

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Synthesis and Mesomorphism of Polymers with Banana-Shaped Mesogens in the Main Chain

  • Choi, E-Joon;Zin, Wang-Cheol;Kim, Young-Chul;Paek, Sang-Hyon;Chien, Liang-Chy;Samulski, Edward T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.171-174
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    • 2006
  • In this work, we report the synthesis and characterization of azomethine-ester polymers that consist of banana-shaped mesogen in their backbone. Two parts of the key structure of five-ring bent-core mesogen were modified by connecting different angle of central unit (Ar), and introducing lateral substituent into the outer ring (X). The synthetic details includes (1) placing the dioxydodecamethylene unit as a flexible spacer, (2) possessing 2,3- or 2,7-naphthylene, or 1,2-phenylene connection on the central unit, and (3) introducing fluorine or chlorine substituent (X = F or Cl) into the outer phenylene unit.

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The Coupling Analysis of Electromagnetic Wave to Transmission Line using Nonhomogeneous Differential Equations (비동차 미분 방정식을 이용한 외부전자파에 의한 전송선로 결합 해석)

  • Myung, Sung-Ho;Lee, Ki-Chul
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.552-556
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    • 1989
  • The line equations can be expressed by a set of nonhomogeneous differential equation where forcing terms of these equations have been adopted. Equivalent-circuit representations of this paper are derived from solutions of the equations. The contribution of the external wave to the line is expressed in terms of ideal sources in the form of a cascade connection to the line. These representations art conveniently applicable to the various types of transmission lines because these Lines can often be written in the form of a chain matrix.

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Call Blocking Probabilities of Dynamic Routing Algorithms in B-ISDN Networks

  • Bahk, Sae-woong;Kim, Joon-hwan
    • Journal of Electrical Engineering and information Science
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    • v.3 no.1
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    • pp.21-27
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    • 1998
  • In this paper we apply routing algorithms in circuit switched networks to B-ISDN networks and investigate the performance. B-ISDN supports a wide range of services with hetrogeneous bandwidth requirements. We assume that the network supports D classes of traffic. It is modeled as a finite D dimensional Markov chain. A call is blocked on arrival if the required bandwidth is not available on the route. The shortest path routing, alternate routing and trunk reservation are considered for performance comparison. We also consider trunk reservation with restricted access control where the network reserves certain amount of bandwidths for one class of traffic that assumes a higher transmission priority. Through the method of successive iterations, we obtain the steady state equilibrium probabilities and call blocking probabilities for dynamic routing. The results can be used to design a B-ISDN network that improves network connection availability and efficiency while simultaneously reducing the network costs.

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The gut microbiota: a key regulator of metabolic diseases

  • Yang, Jin-Young;Kweon, Mi-Na
    • BMB Reports
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    • v.49 no.10
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    • pp.536-541
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    • 2016
  • The prevalence of obesity and type 2 diabetes, two closely linked metabolic disorders, is increasing worldwide. Over the past decade, the connection between these disorders and the microbiota of the gut has become a major focus of biomedical research, with recent studies demonstrating the fundamental role of intestinal microbiota in the regulation and pathogenesis of metabolic disorders. Because of the complexity of the microbiota community, however, the underlying molecular mechanisms by which the gut microbiota is associated with metabolic disorders remain poorly understood. In this review, we summarize recent studies that investigate the role of the microbiota in both human subjects and animal models of disease and discuss relevant therapeutic targets for future research.

Oxyresveratrol Derivative Compound DMPB Act as Potent Dipigment agent in Brown Guinea Pig Skin

  • Choi, Sang-Yoon;Kim, Sang-Hee;Hwang, Jae-Sung;Kim, Ho-Cheol;Kim, Sun-Yeou
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.92.2-93
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    • 2003
  • This study with the object of reported to depigment agent, oxyresveratrol derivative, compound DMPB. Compound DMPB with a two methoxy groups and modified connection chain. It was synthesized in accordance with a simple combination process. Compound DMPB exhibits depigmentaion ability on ultraviolet B-induced hyperpigmention of the brown guinea pig skin. In addition, this Compound exhibited 30% inhibitory effect of melanin generation without cell toxicity as a result of the treatment with 100 ppm in melan-a cells. (omitted)

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Insights into the Roles of Prebiotics and Probiotics in the Large Intestine (대장에서 prebiotics와 probiotics 역할에 대한 조명)

  • An, Su Jin;Kim, Jae Yeong;Choi, In Soon;Cho, Kwang Keun
    • Journal of Life Science
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    • v.23 no.10
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    • pp.1295-1303
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    • 2013
  • According to facts revealed up until the present, there are a total of 68 known phyla on earth, including 55 phyla of bacteria and 13 phyla of archaea. The human large intestine has 9 phyla of microorganisms, which is a relatively lower diversity compared to the general environments of soil or sea. The diversity of intestinal microorganisms is affected by the characteristics of the host (genetic background, sex, age, immune system, and gut motility), the diet (non-digestible carbohydrates, fat, prebiotics, probiotics), and the intake of antibiotics, which in turn have an effect on energy storage processes, gene expressions, and even metabolic diseases like obesity. Probiotics are referred to as living microorganisms that improve the intestinal microbiota and contribute to the health of the host; in addition, probiotics usually comprise lactic acid bacteria. Recently, bacteriotherapy using probiotics has been utilized to treat sicknesses like diarrhea and irritable bowel syndrome. Prebiotics are a food ingredient which can selectively adjust intestinal microorganisms and which comprise inulin, fructooligosaccharides, galactooligosaccharides, and lactulose. In recent days, attention has been paid to the use of dietary cellulose in the large intestine and the production of short chain fatty acids (short-chain fatty acids) in relation to obesity and anticancer. More research into microorganisms in the large intestine is necessary to identify specific microorganism species, which are adjusted by diverse non-digestible carbohydrates, prebiotics, and probiotics in the large intestine and to understand the connection between sicknesses and metabolites like short chain fatty acids produced by these microorganism species.

Dispersity of Silver Particles in Polyurethane Matrix: Effect of Polyurethane Chemical Structure (폴리우레탄 구조 변화에 따른 은 입자의 분산 특성)

  • Im, Hyun-Gu;Lee, Hyuk-Soo;Kim, Joo-Heon
    • Polymer(Korea)
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    • v.31 no.6
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    • pp.543-549
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    • 2007
  • We synthesized various polyurethanes(PU) haying different hard segments with different molecular weights of the soft segment to explore the effect of structure on the dispersion of silver particle in the phase of synthesized polyurethanes matrix. The thermal stability was increased by increasing the number of aromatic compound, while the degree of dispersion for silver particle was decreased. Silver particles showed better dispersion in the PU matrix having aromatic compounds when the soft segments were held constant. On the contrary, when the hard segment was held constant, silver particles on the PU matrix haying low $M_w$ of soft segment showed better dispersion than high $M_w$ of soft segment because poor chain mobility of low $M_w$ of soft segment restricted re-aggregation of silver particle. A sheet resistance of composite materials showed different aspects. In this case, the inter connection between silver particles was more important than its dispersion. In this study, the NDI-PEG 900/silver particle composite film showed the best thermal stability and electro conductivity.

A study on Kerberos Authentication and Key Exchange based on PKINIT (PKINIT기반의 Kerberos 인증과 키 교환에 관한 연구)

  • Sin, Gwang-Cheol;Jeong, Il-Yong;Jeong, Jin-Uk
    • The KIPS Transactions:PartC
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    • v.9C no.3
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    • pp.313-322
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    • 2002
  • In this paper, proposes Kerberos certification mechanism that improve certification service of PKINIT base that announce in IETF CAT Working Ggroup. Did to certificate other realm because search position of outside realm through DNS and apply X.509 directory certification system, acquire public key from DNS server by chain (CertPath) between realms by certification and Key exchange way that provide service between realms applying X.509, DS/BNS of PKINIT base. In order to provide regional services, Certification and key exchange between realms use Kerberos' symmetric method and Session connection used Directory service to connection X.509 is designed using an asymmetric method. Excluded random number ($K_{rand}$) generation and duplex encryption progress to confirm Client. A Design of Kerberos system that have effect and simplification of certification formality that reduce Overload on communication.

The State-of-the-art of Discovering New Suppliers to Build a Supply Chain (공급망 형성을 위한 협업기업 발굴방법의 최신 동향 분석)

  • Kim, Kyung-Doc;Jo, Bo-Ram;Shin, Moon-Soo;Ryu, Kwang-Yeol;Cho, Hyun-Bo
    • IE interfaces
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    • v.25 no.1
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    • pp.21-30
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    • 2012
  • In the past, buyers and suppliers met each other to find common interests off-line in exhibitions and conferences, or through personal connection. These activities were time consuming and costly. With the advent of information era, these activities moved to online market places, where buyers search for suppliers with a set of keywords that are believed to be representative of their requirements. Its fundamental assumption is that all the potential candidates are registered in a certain database. However, recently buyers want to diversify suppliers due to needs of cost competitiveness or frequent new product development. To this end, instead of choosing suppliers from the supplier pool, discovering suppliers from all over the world should be emphasized. In order to enable buyers to describe their requirements and suppliers to capture their manufacturing capabilities via online market places, the semantic differences of terms between buyers and suppliers should be resolved. The paper summarizes various supplier discovery frameworks and prototype systems, which can be employed to expose domestic small-medium enterprises into global buyers in the near future.