• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년 추계학술대회논문집
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• pp.359-366
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• 2008

Current state and perspective of DNS of turbulence and turbulent combustion are discussed with feature trend of the fastest supercomputer in the world. Based on the perspective of DNS of turbulent combustion, possibility of perfect simulations of IC engine is shown. In 2020, the perfect simulation will be realized with 30 billion grid points by 1EXAFlops supercomputer, which requires 4 months CPU time. The CPU time will be reduced to about 4 days if several developments were achieved in the current fundamental researches. To shorten CPU time required for DNS of turbulent combustion, two numerical methods are introduced to full-explicit full-compressible DNS code. One is compact finite difference filter to reduce spatial resolution requirements and numerical oscillations in small scales, and another is well-known point-implicit scheme to avoid quite small time integration of the order of nanosecond for fully explicit DNS. Availability and accuracy of these numerical methods have been confirmed carefully for auto-ignition, planar laminar flame and turbulent premixed flames. To realize DNS of IC engine with realistic kinetic mechanism, several DNS of elemental combustion process in IC engines has been conducted.

• 생명과학회지
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• 제10권2호
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• pp.210-217
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• 2000

A kinetic profile of the catalytic domain of stromelysin-1 (SCD) using the fluorescent peptide substrate has been determined by the stopped-flow technique. The pH profile has a pH optimum of about 5.5 with an extended shoulder above pH 7. Three pKa values, 5.0, 5.7, and 9.8 are found for the free enzyme state and two pH independent Kcat/Km values of 4.1$\times$104 M-1 s-1 and 1.4$\times$104 M-1 s-1 at low and high pH, respectively. The profile is quite different in shape with other MMP family which has been reported, having broad pH optimum with two pKa values. The substrate specificity of SCD towards fluorescent heptapeptide substrates has been also examined by thin layer chromatography. The cleavage sites of the substrates have been identified using reverse-phase HPLC method.SCD cleaves Dns-PLA↓L↓WAR and Dns-PLA↓L↓FAR at two positions. However, the Dns-PLA↓LRAR, Dns-PLE↓LFAR, adn Dns-PLSar↓LFAR are cleaved exclusively at one bond. The double cleavages of Dns-PLALWAR and Dns-PLALFAR by SCD are in marked contrast to the close structurally related matrilysin. A notable feature of SCD catalysis agrees with the structural data that the S1' pocket of SCD is deeper than that of matriysin. The differences observed between SCD and matrilysin may form the basis of understanding the structural relationships and substrate specificities of the MMP family in vivo.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2007년도 춘계학술발표대회
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• pp.917-920
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• 2007

DNS(Domain Name Service) 시스템은 도메인 네임을 사용하여 IP를 얻을 수 있도록 해주는 시스템이다. DNS는 도메인 네임을 이용하여 IP 주소를 얻기 위해서만 사용하는 것이 아니다. 그 외에 DNS와 관련된 서비스 혹은 정보들을 DNS를 통해서 얻을 수가 있다. IP-USN (IP-Ubiqitous Sensor Network) 환경은 IP를 사용하는 USN 환경이므로 IP 네트워크에서 사용가능한 기술을 그대로 적용할 수가 있다. DNS 시스템을 이용하여 IP-USN 환경의 노드가 필요한 서비스를 탐색하기 위한 효과적인 구조에 대해서 연구한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(1)
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• pp.351-354
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• 2002

NAPTR(Naming Authority Pointer) is a type of resource record specified IETF RFC 2915. NAPTR enables to register various services in tile domain name systems and thus Provides a way to discover services available on specific hosts. This paper describes the design and implementation of a proxy DNS system aimed at supporting NAPTRS. The goal of this work is to study on the feasibility of the service discovery registered in DNS via NAPTR records. This research result can be applied to service discovery in the resource information management for high performance GRID environments as well as to implement generic ENUM services

• 한국전문물리치료학회지
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• 제26권4호
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• pp.1-9
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• 2019

Background: Cervical dysfunction is a common pathomechanical marker in individuals with forward head posture (FHP). To overcome the limitations of the isometric chin-tuck (ICT) exercise, dynamic neuromuscular stabilization (DNS), which emphasizes an entire spinal chain exercise, has recently shown promising clinical results. Objects: Purpose of this study was to compare the immediate effects between ICT and DNS techniques. Methods: 43 young subjects (mean age, $24.0{\pm}5.0$ years) were recruited. Group of subjects with FHP were measured under baseline, ICT, and DNS conditions. Outcome measures included sitting height, longus colli (LC) and sternocleidomastoid (SCM) muscle thickness and LC/SCM thickness ratio. One-way repeated measures ANOVA was used to compare the continuous dependent variables among FHP, ICT, and DNS conditions at p<.016. Results: Both ICT and DNS exercise conditions yielded significantly increased LC muscle thickness, LC/SCM thickness ratio and sitting height than did FHP condition (p<.0001, respectively). Sitting height was significantly greater in DNS exercise than in the ICT exercise (p<.0001). Conclusion: The present results demonstrated that sitting height was greater in the DNS exercise than in the ICT exercise, as well as both corrective postural training exercises were effective on LC/SCM muscle balance ratio when compared with the baseline FHP condition. Therefore, it is considered that DNS exercise can be the recommended exercise for people with FHP.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권4호
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• pp.895-909
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• 2013

Distributed Denial-of-Service (DDoS) attacks towards name servers of the Domain Name System (DNS) have threaten to disrupt this critical service. This paper studies the vulnerability of the cache server to the flooding DNS query traffic. As the resolution service provided by cache server, the incoming DNS requests, even the massive attacking traffic, are maintained in the waiting queue. The sojourn of requests lasts until the corresponding responses are returned from the authoritative server or time out. The victim cache server is thus overloaded by the pounding traffic and thereafter goes down. The impact of such attacks is analyzed via the model of queuing process in both cache server and authoritative server. Some specific limits hold for this practical dual queuing process, such as the limited sojourn time in the queue of cache server and the independence of the two queuing processes. The analytical results are presented to evaluate the impact of DDoS attacks on cache server. Finally, numerical results are provided for further analysis.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2007년도 춘계학술발표대회
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• pp.1323-1326
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• 2007

현재 전 세계는 IPv6 조기 도입을 위한 노력을 기울이고 있으며 전략적인 IPv6 인프라 구축 사업을 추진을 하고 있다. 그러나 완전히 IPv6로 전이되기 전까지 IPv4와 IPv6가 공존해야만 한다. 이에 따라 IPv4망에서 IPv6망으로의 안정적인 전이를 위한 상호 운영기술이 필요하다. 이러한 기술을 적용하기 위한 다양한 응용 프로그램의 운영을 위해서 IPv6 기반의 DNS 기술은 그 핵심적인 요소라 할 수 있다. IPv6를 지원하는 Recursive DNS는 기존의 IPv4 기반의 데이터베이스 구조와 플랫폼 및 OS를 IPv6 기반으로 변경해야 하며 IPv4 기반의 DNS 메시지 구조와 이를 처리하는 DNS의 네임 레졸루션 기능이 확장되어야 한다. 따라서 이 논문에서는 IPv6 망 전이를 위하여 변환 프로토콜인 NAT-PT를 이용한 Recursive DNS 구성 방안을 제시한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(1)
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• pp.307-310
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• 2002

This paper is proposed due to the fact that resolving domain name with conventional input method to PDA is not so convenient. The substance of this paper is that a user Pronounces tile character which represents tile domain name and that vocalized character is transferred through the GATEWAY, where DNS service can be received in return. PDA receives, compress and send the voice to the GATEWAY, Then, the GATEWAY uncompress, recognizes the voice, converts to characters, search for the mapping entry After mapping to the mapping entry, the GATEWAY sends the DNS request. Combining two entities makes DNS service based on the human voice possible.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2007년도 한국컴퓨터종합학술대회논문집 Vol.34 No.1 (D)
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• pp.327-332
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• 2007

현재 전 세계는 IPv4 주소 자원의 고갈에 대비한 IPv6의 도입을 위해 국가 차원의 전략적인 노력을 기울이고 있으며, 이에 따라 IPv4망에서 IPv6망으로의 안정적인 전이를 위한 상호 운영기술이 지속적으로 개발되고 있다. 이러한 기술을 적용하기 위한 다양한 응용 프로그램의 운영을 위해서 IPv6 뿐만 아니라 IPv6 기반의 Recursive DNS 기술도 그 핵심적인 요소라 할 수 있다. 그렇지만 IPv6 및 IPv6 DNS를 구축과 동시에 사용자 PC의 OS에도 IPv6 및 IPv6 DNS가 설정되어야 한다. 그러나 사용자가 사용하는 운영체제의 종류가 다양하기 때문에 운영체제별 동작도 다르다. 따라서 IPv6 및 IPv6 Recursive DNS을 사용하기 위해서는 사용자 PC의 서로 상이한 운영체제별 IPv6 및 IPv6 DNS 동작을 파악해야만 한다. 이에 본 논문은 운영체제별 IPv6 및 IPv6 DNS 동작을 확인하고 IPv6 및 IPv6 DNS 구축시 고려해야 할 가이드라인을 제시한다.

• 약학회지
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• 제34권3호
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• pp.215-218
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• 1990

An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.