• Title/Summary/Keyword: AD

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Distributed Implementation of Delay Guaranteed Fair Queueing(DGFQ) in Multimedia Ad Hoc Wireless Networks (멀티미디어 Ad Hoc 무선망에서 지연시간 보장 공정큐잉(DGFQ)의 분산적 구현)

  • Yang Hyun-Ho
    • The Journal of the Korea Contents Association
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    • v.5 no.4
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    • pp.245-253
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    • 2005
  • The multimedia ad hoc wireless network is quite an attractive issue since it offers a flexible solution to enable delivery of multimedia services to mobile end users without fixed backbone networks. However, with the unique design challenges of ad hoc wireless networks, it is a non-trivial issue to provide bounded delay guarantee, with fair share of resources. In this paper, we proposed distributed implementation of the delay guaranteed fair queueing (DGFQ) scheme in multimedia ad hoc wireless networks. Through the the results of performance evaluation, we can conclude that DGFQ also performs well to control bounded delay in multimedia ad hoc wireless networks.

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A Study on Group Key Management based on Mobile Device ID in Ad-hoc network (Ad-hoc 네트워크에서 모바일 디바이스 아이디 기반의 그룹 키 관리에 대한 연구)

  • Kang, Seo-Il;Lee, Nam-Hoon;Lee, Im-Yeong
    • Journal of Korea Multimedia Society
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    • v.12 no.4
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    • pp.540-549
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    • 2009
  • An arbitrary mobile device configures Ad-hoc network to provide the transmission of a data and services using wireless communications. A mobile device requires authentication and encryption key management to securely communicate in the Ad-hoc network. This paper examines the trend of the authentication in the Ad-hoc network and the group key management and suggests the plan for ID-based mutual authentication and group key establishment. ID-based mutual authentication in proposed scheme uses zero knowledge in the absence of shared information and is applied to establish a session key and group key. In addition, the proposed scheme is applied to Ad-hoc network to increase the efficiency and the safety of security technology.

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Performance Improvement of AD-MUSIC Algorithm Using Newton Iteration (뉴턴 반복을 이용한 AD-MUSIC 알고리즘 성능향상)

  • Paik, Ji Woong;Kim, Jong-Mann;Lee, Joon-Ho
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.11
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    • pp.880-885
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    • 2017
  • In AD-MUSIC algorithm, DOD/DOA can be estimated without computationally expensive two-dimensional search. In this paper, to further reduce the computational complexity, the Newton type method has been applied to one-dimensional search. In this paper, we summarize the formulation of the AD-MUSIC algorithm, and present how to apply Newton-type iteration to AD-MUSIC algorithm for improvement of the accuracy of the DOD/DOA estimates. Numerical results are presented to show that the proposed scheme is efficient in the viewpoints of computational burden and estimation accuracy.

Effects of Selective Thromboxane $A_2$-Receptor Antagonist, KT2-962 on Adriamycin-induced Nephrotoxicity in Rats (흰쥐에서 Adriamycin-유발 신독성에 대한 Thromboxane $A_2$ 수용체 길항제인 KT2-962의 효과)

  • 문삼영;이순복;신현진;고현철;엄애선;강주섭
    • Biomolecules & Therapeutics
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    • v.8 no.3
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    • pp.241-247
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    • 2000
  • The present study was designed to assess the protective effect of a selective thromboxane $A_2$ receptor antagonist, KT2-962 (KT2) and possible mechanisms of adriamycin(AD)-induced nephrotoxicity in rats. The male Wistar rats were given either of AD (7.5 mg/kg, i.v.) alone in the AD-group (n=5) or in KT2+AD- group (n=5) which is a combination of AD and KT2 (30 mg/kg/day, i.p.) for 10 days from 3 days before and 7 days after AD injection. The body weight, 24-hours urine volume, urine protein and urinary N-acetyl-$\beta$-D-glu-cosaminidase (NAG) activity were measured with an interval of 2 days during 1 week. BUN, serum creatinine and creatinine clearance were measured on the 7th day. KT2 has significantly suppressed AD-induced change of body weight, 24-hours urine volume, urine protein and urinary NAG activity in the KT2+AD-group. The change of BUN, serum creatinine and creatinine clearance were significantly inhibited in the B7T2+AD-group. Based on these results, it is concluded that KT2 prevents AD-induced nephrotoxicity and suggests that endogenous thromboxane A2 may play an important role in AD-induced nephrotoxicity in rats.

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Effects of Restricted Feeding on Performance, Carcass Quality and Hormone Profiles in Finishing Barrows

  • Cho, S.B.;Cho, S.H.;Chang, S.S.;Chung, I.B.;Lim, J.S.;Kil, D.Y.;Kim, Yoo Yong
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.11
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    • pp.1643-1648
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    • 2006
  • To investigate the effects of feeding restricted on growth, carcass characteristics and plasma profiles in an attempt for optimum responses, a total of 108 cross-bred finishing barrows [(Landrace${\times}$Yorkshire)${\times}$Duroc]weighing an average of $46.88{\pm}0.52kg$ were assigned in a randomized complete block (RCB) design to one of four treatments with three replicates and nine pigs per pen. Feeding regimens were, 1) ad libitum from 50 kg to market weight (Ad 3/3), 2) restricted feeding from 90 kg to market weight (Ad 2/3), 3) restricted feeding from 70 kg to market weight (Ad 1/3), and 4) restricted feeding from 50 kg to market weight (Ad 0/3). During the experimental period, average daily feed intake (ADFI) was decreased from 2.53 kg (AD 3/3) to 2.09 kg (AD 0/3) with increasing restricted feeding duration of (p<0.05). Average daily gain (ADG) of AD 3/3 (0.79 kg) was significantly higher (p<0.05) than those of AD 1/3 (0.74 kg) or AD 0/3 (0.72 kg). Feed efficiency was not influenced by restriction regimens. Blood IGF-I concentrations were increased from 74.14 to 134.25 (167.36-115.66) ng/ml as body weight increased. Blood leptin concentrations were affected by feed intake level and coincided with blood IGF-I concentrations. Most of carcass characteristics were not significantly affected by restricted feeding, however cooking losses in AD 1/3 and Ad 0/3 treatment diet were higher than those in Ad 3/3 and Ad 2/3. In addition, there was a trend that backfat thickness was lowered in proportional to decreasing feed intake (p>0.05). In conclusion, restricted feeding improved feed efficiency after 50 kg body weight without deteriorating the pork quality of barrows.

Mutual Authentication between the mobile node in Ad-hoc Network (Ad-hoc 망에서 이동 노드 간 상호 인증)

  • Choi, Woo-Jin;Seok, Gyeong-Hyu
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.10
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    • pp.1087-1092
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    • 2015
  • It was diversified demand for a wireless network to the rapid growth of the Internet, the time and space that are not in the new level of Internet technology, limits the Ad-hoc networks are needed. Ad-hoc networks do not communicate with the central station, each of the mobile nodes included in the network communicate with each other by the relay role. In recent years, the Ad-hoc wireless networks in a variety of routing protocols and network security, research is actively underway for the authentication method, but the security of wireless Internet and Ad-hoc networks, certification is incomplete situation. This paper considers the authentication and key agreement technique applicability of the USIM card using the DSR routing protocol of the Java Card and Ad-hoc networks, we propose a secure authentication mechanism between the mobile node.

Adenovirus types in pediatric gastroenteritis in seoul (서울 지역 장염환아에서 분리되는 아데노바이러스 형별)

  • Cho, Eun-Kyung;Lee, Kyu-Man;Chung, Yong-Hoon;Cho, Yang-Ja;Kim, Kyung-Hee
    • Pediatric Infection and Vaccine
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    • v.3 no.1
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    • pp.76-85
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    • 1996
  • Adenoviruses(Ad) are considered to be second only to rotaviruses as the most significant cause of gastroenteritis in young children in Korea and thus it is essential to know the full spectrum of Ad serotypes routinely present in stool specimens from symptomatic patients. Sixty-six Ad isolates and three questionable ones collected over a 2-year peiord were typed by standard microneutralization, restriction endonuclease digestion and PCR of viral DNA to be able to evaluate these assays comprehensively for their ability to identify Ad associated with gastroenteritis. A total of sixty-one isolates(88.4%) were typed: the predominant types were Ad type 41(Ad41)(26.2%), Ad2(19.7%), Ad40(14.8%), Ad5(9.8%), and Ad7(9.8%) which together accounted for almost 80% of the isolates. The remaining virus isolates were typed as Ad1, 31, 34, 3, 25 and a mixture of 40/41. The incidence of Ad31(4.9%) or Ad3(1.6%) was relatively insignificant. DNA restriction analysis(77.5%) proved to be better than serum neutralization but not so when compared to a PCR-based assay for identification of the enteric Ad serotypes(90%) in stool specimens. In this work, the PCR-based assay was evaluated as a tool for the rapid, yet highly sensitive identification of adenoviral DNA sequences in fresh clinical stool specimens.

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The Study on the Effective Prevention Mechanism of Masquerade Attacks on Wireless Ad hoc Network (무선 Ad hoc 네트워크의 효율적인 위장 공격 방지 메커니즘에 관한 연구)

  • Hong, Soon-Jwa;Park, Hyun-Dong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.6
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    • pp.135-149
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    • 2006
  • Securing wireless Ad hoc network including the secure mechanism design and implementation is generally more difficult for vulnerability of channels and nodes, the absence of infrastructure, topology that change dynamically, and etc, than ire network. The efforts of early researches are based on the adaptation of securing methods for the wire network to wireless ad hoc network. However, wireless ad hoc network could not get effective study finding because network has essential problems. This paper proposes that some new problems are being came to light over the survivability and availability of the network itself, that are caused by the massive packet attack of more than one or two nodes, and proves the consequence of this phenomenon. Also, we propose an effective prevention mechanism of masquerade attacks for survivability reinforcement that escape standard of the early way by survivability of wireless Ad hoc network and approaches for performance elevation and reflect special quality of wireless Ad hoc network.

An Empirical Study for Model Development Concerning Advance Directive (사전의료지시서(Advance Directives) 모형 개발을 위한 실증 연구)

  • Hong, Seongae
    • 한국노년학
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    • v.30 no.4
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    • pp.1197-1211
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    • 2010
  • This research was concucted to present a model of advance directives(AD) when a patient, who is in consciousness, shows a preference for an end of life care as an act of preparing for an uncertain situation that may arise in the forseeable future. The subjects of the research are 383 doctors/nurese and adults, who live in six cities and provinces, to investigate the status of AD, attitude regarding a meaningless life-prolonging treatment, and moreover, an understanding of and a preference for AD. The research was done by the well-structured questionnaire. Also, SPSS 14.0 is used to analyse the collected data, focused on frequency analysis, avearage and standard deviation, X2 test. As the results of the study, the most of the surveyed doctors/nurese knew DNR orders and AD and a few of them used DNR orders and AD practically. Also, the result shows that there is a negative conception of meaningless life-prolonging treatment among the responents, in addition, most of them agreed upon the idea of introducing AD to Korea, filling it out and making it legally effective. As a method of making AD out, the respondents wanted to use a form that mixed living will with an Power of Attorney in a document. Also, considering the appropriate time, respondents prefered when they are diagnosed with terminal illness. At the moment, the introductory model for AD, which is suitable for the Korean culture and current situation is presented based on the result of this research. In the future, other researches should deal with specific measures that can lead to a social consensus to adopt AD in Korea.

Expression and Purification of Three Lipases (LipAD1, LipAD2, and LipAD3) and a Lipase Chaperone (LipBD) from Acinetobacter schindleri DYL129 (Acinetobacter schindleri DYL129 유래의 3개 lipases와 chaperone의 발현과 정제)

  • Kim, Sun-Hee;Lee, Yong-Suk;Jeong, Hae-Rin;Pyeon, Hyo-Min;You, Ju-Soon;Choi, Yong-Lark
    • Journal of Life Science
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    • v.29 no.4
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    • pp.492-498
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    • 2019
  • Previously, three kinds of lipases, lipAD1, lipAD2, and lipAD3, and lipase chaperone, lipBD, of Acinetobacter schindleri DYL129 isolated from soil sample were reported. In this report, three lipase and lipase chaperone were cloned into the pET32a(+) or pGEX-6P-1 vectors for protein expression in Escherichia coli, and named as pETLAD1, pETLAD2, pETLAD3 and pETLBD or pGEXLAD1, pGEXLAD 2, pGEXLAD3 and pGEXLBD, respectively. Protein expression rate was higher in pET system than in pGEX system. Although LipAD1 and LipAD2 were produced as inclusion bodies, their expression levels were high. So LipAD1 and LipAD2 could be solubilized in 8 M urea buffer and purified. LipAD3 and LipBD were overexpressed in soluble form and purified. Those proteins were purified by His-tag affinity chromatography connected in AKTA prime system. The activities of the purified lipases were demonstrated with 1% tributyrin agar plate. After purification, molecular mass was determined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis. LipAD1 showed high activity toward ${\rho}$-nitrophenyl acetate and ${\rho}$-nitrophenyl butyrate, LipAD2 showed high activity toward ${\rho}$-nitrophenyl acetate and ${\rho}$-nitrophenyl myristate, and LipAD3 showed high activity toward ${\rho}$-nitrophenyl acetate, ${\rho}$-nitrophenyl butyrate, and ${\rho}$-nitrophenyl miristate, respectively. Three lipases, LipAD1, LipAD2, and LipAD3, showed optimal reaction at $50^{\circ}C$ using ${\rho}$-nitrophenyl butyrate, as substrate.