• Journal of Information Processing Systems
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• 제6권2호
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• pp.177-184
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• 2010

Secure routing is vital to the acceptance and use of Wireless Sensor Networks (WSN) for many applications. However, providing secure routing in WSNs is a challenging task due to the inherently constrained capabilities of sensor nodes. Although a wide variety of routing protocols have been proposed for WSNs, most do not take security into account as a main goal. Routing attacks can have devastating effects on WSNs and present a major challenge when designing robust security mechanisms for WSNs. In this paper, we examine some of the most common routing attacks in WSNs. In particular, we focus on the wormhole routing attack in some detail. A variety of countermeasures have been proposed in the literature for such attacks. However, most of these countermeasures suffer from flaws that essentially render them ineffective for use in large scale WSN deployments. Due to the inherent constraints found in WSNs, there is a need for lightweight and robust security mechanisms. The examination of the wormhole routing attack and some of the proposed countermeasures makes it evident that it is extremely difficult to retrofit existing protocols with defenses against routing attacks. It is suggested that one of the ways to approach this rich field of research problems in WSNs could be to carefully design new routing protocols in which attacks such as wormholes can be rendered meaningless.

• 한국작물학회지
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• 제51권2호
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• pp.142-147
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• 2006

The present study describes carbohydrate metabolism, macro-element utilization and antioxidant defenses in response to an ozone dose (100 ppb, 8d) in two rice varieties. Tolerant (cv. Jinpumbyeo) and sensitive (cv. Chucheongbyeo) varieties of rice were grown in growth chamber for 30 days after sowing. Concentrations of chloroplast pigments and non-structural carbohydrates as well as activity of antioxidant enzymes were determined to evaluate the resistance against ozone stress. Ozone caused the decrease in chlorophyll a and carotenoid contents, and also resulted in faster decomposition of non-structural carbohydrate in leaf blade and leaf sheath. The contents of nitrogen and potassium in leaves were visibly decreased in cv. Chucheongbyeo with an increase in ozone exposure, but not in cv. Jinpumbyeo. Enzymatic antioxidants against ROS in both varieties responded in the order of POD, SOD and CAT, and their capacity was stronger in cv. Jinpumbyeo.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1819-1825
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• 2006

Four naphthalene-degrading bacteria (Pseudomonas sp. strains O1, W1, As1, and G1) were isolated feom pollutant-contaminated sites. Examination of their substrate utilization and analyses of key naphthalene-catabolic regulatory genes revealed that the pathway and regulation of naphthalene-degradation in all four strains resemble those of NAH7 from P. putida G7. Superoxide anion production, superoxide dismutase activity, and catalase activity during their growth on naphthalene-amended medium increased significantly, compared with those with glucose-amended medium. Addition of ascorbate, an antioxidant, or ferrous iron ($Fe^{2+}$) increased the growth rates of all tested microorganisms on naphthalene. Northern blot and HPLC analyses showed that both nahA gene expression and naphthalene degradation increased under those conditions. Our data suggest that naphthalene degradation can impose severe oxidative stress, and defenses against oxidative stress would play an important role in the metabolism of naphthalene.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.101-108
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• 2020

Infections by herpes simplex viruses have an immense impact on humans, ranging from self-limiting, benign illness to serious, life-threatening diseases. While nucleoside analog drugs are available, resistance has been increasing and currently no vaccine exists. Ginsenosides derived from Panax ginseng have been documented to inhibit several viruses and bolster immune defenses. This study evaluated 12 of the most relevant ginsenosides from P. ginseng for toxicities and inhibition of herpes simplex viruses types 1 and 2 in Vero cells. The effects of test compounds and virus infection were determined using a PrestoBlue cell viability assay. Time course studies were also conducted to better understand at what points the virus life cycle was affected. Non-toxic concentrations of the ginsenosides were determined and ranged from 12.5 μM to greater than 100 μM. Ginsenoside 20(S)-Rg3 demonstrated the greatest inhibitory effect and was active against both HSV-1 and HSV-2 with an IC₅₀ of approximately 35 μM. The most dramatic inhibition-over 100% compared to controls-occurred when the virus was exposed to 20(S)-Rg3 for 4 h prior to being added to cells. 20(S)-Rg3 holds promise as a potential chemotherapeutic agent against herpes simplex viruses and, when used together with valacyclovir, may prevent increased resistance to drugs.

• Nutrition Research and Practice
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• 제1권1호
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• pp.14-18
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• 2007

This study investigated the effect of physical training and oxidative stress on the anti oxidative activity and on plasma lipid profile. Forty eight rats were given either a physical training or no training for 4 weeks and were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The antioxidative activity was evaluated with the activities of catalase in plasma and superoxide dismutase (SOD), the ratio of reduced glutathione/ oxidized glutathione (GSH/GSSG) and the level of malondialdehyde (MDA) in liver. The plasma concentrations of triglyceride (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C)) were also compared. Compared to those of non-training group. catalase activities of training group were lower before exercise but higher during and after exercise. SOD activities were higher regardless of exercise. GSH/GSSG ratio was higher before exercise but was not significantly different during exercise and even lower after exercise. There were no differences between non-training group and training group in MDA levels regardless of exercise. Compared to those of non-training group, atherosclerotic index of training group was lower after exercise and there were no significant differences before and during exercise. There were no differences between non-training group and training group in HDL-C regardless of exercise. These results suggest that moderate physical training can activate antioxidant defenses and decrease the atherosclerotic index and this beneficial effect is evident under exercise-induced oxidative stress.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제6권7호
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• pp.321-328
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• 2017

사이버 위협이 고도화되고 지능화되어짐에 따라 사이버 침해사고로 인한 피해사례가 급격하게 증가하고 있다. 이로 인해 사이버보안 전문인력의 중요성을 인식하여 다수의 사이버 보안관련 교육 프로그램이 운영되고 있지만 사이버보안 인력 현황 및 직무에 기반한 사이버보안 교육연구가 이루어지 않아서 교육 수요자 및 공급자가 목표한 교육과정이 제공되지 않고 있다. 이에 따라 본 연구에서는 사이버보안 인력 및 지식체계를 정의하고 이를 반영한 새로운 사이버보안 교육 커리큘럼을 개발하였다. 본 연구에서 개발한 교육 커리큘럼은 기존 교육 커리큘럼에서 강조하고 있는 방어와 관련된 교육내용만으로 구성하는 것이 아니라, 공격분야의 교육내용을 추가하여 전문적이고 균형적인 사이버보안 인력양성을 위한 교육 커리큘럼을 개발 및 개선하였다.

• Journal of Acupuncture Research
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• 제25권1호
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• pp.107-120
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• 2008

Objectives : This study investigated the antioxidant effect of electro-acupuncture at $KI_6$ on rats treated with 2,2'-azobis(2-amidinopropane) dihydrochloride(AAPH). Methods : After electro-acupuncture at $KI_6$ on 48 rats that were given AAPH(50mg/kg) every day, the author observed several changes in weight, liver index, albumin, total bilirubin, LDL-cholesterol, LDH, glucose, GOT, GPT, SOD and catalase activity, and glutathione, NO, and MDA concentrations. Results : 1. In the $KI_6-EA$ group, the albumin level increased and LDL-cholesterol decreased compared with the control and holder groups. 2. In the $KI_6-EA$ group, SOD activity increased compared with the holder group, glutathione concentration increased compared with the control and holder groups, and catalase activity increased compared with the control group. 3. In the $KI_6-EA$ group, NO concentration decreased compared with the control and holder groups. Conclusions : This case shows that electro-acupuncture at $KI_6$ plays a significant antioxidant role by elevating defenses against cell toxicity caused by oxidative stress and suppressing oxidative injury.

• 융합보안논문지
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• 제12권4호
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• pp.71-76
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• 2012

Mashups, web 3.0, 자바스크립트 및 AJAX 등의 이용이 증가하면서 웹애플리케이션 서비스 제공시 웹취약점들에 대한 새로운 보안 위협이 증대되고 있으며, 이에 대한 사전 진단과 함께 대비가 요구된다. 본 논문에서는 웹취약성에 대한 보안 위협과 요구사항을 제시하고, Web Vulnerability Scanner(WVS) 자동화 도구를 이용하여 국내에서 서비스되고 있는 웹사이트를 대상으로 웹취약성을 분석한다. Cross Site Scripting(XSS)와 SQL Injection 등 대표적인 웹취약성에 대한 분석 결과, 약 22.5%에 해당하는 웹사이트가 보안에 취약한 것으로 나타났으며, 취약성 경고 수는 0부터 31,171 alerts로 분포되고, 평균 411 alerts, 편차는 2,563 alerts로서 보안 관리에 취약한 웹사이트의 경우, 경고 수가 높은 값을 나타내고 있어 세부적인 웹취약성에 대한 사전 대비가 필요함을 알 수 있다.

• Journal of Construction Engineering and Project Management
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• 제7권1호
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• pp.37-49
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• 2017

The Jinshanling section of the Great Wall of China is a series of fortifications in northern China that was constructed for strategic military defenses. This section was first built in the beginning of the Ming Dynasty in AD 1368 and then underwent major construction, reconstruction and renovation during the late Ming Dynasty, approximately in AD 1569. The Jinshanling section is 10.5 km long, a very short section compared with the entire 21,200 km wall. The wall section is located in Luanping County, Hebei province, China. This research paper focuses on the construction methods and materials of the wall and the towers in the area. The research methodology includes site visits, knowledge acquisition of experts and 3D graphic modeling. This study reveals that the materials selected for the structure include rubbles and rammed earth, bricks, stones, timber, and mortar. The erection sequence of the wall and the towers was a bottom-up fashion using various ancient construction techniques, such as the fire-setting rock blasting techniques and the surveying techniques from the Sea Island Mathematical Manual.

• 한국중재학회지:중재연구
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• 제21권1호
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• pp.73-86
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• 2011

Today's arbitrations see themselves as the most effective scheme for dispute resolution in a variety of transactional context. While some kind of ADR system was already introduced in Korea as of 2007 with revision of the Consumer Basic Law, consumers' needs in dispute resolution remain unmet. Recently one consumer arbitration case divides the U.S. Supreme Court. Of course, the result of the case is expected to affect tens of millions of arbitration agreements in the States which has the most developed scheme in consumer arbitrations. While Arbitration clauses in adhesion contracts are not automatically held to be substantively unconscionable, Class action waivers are one of the most controversial issues in consumer arbitration. In this study, with the theoretical background of consumer arbitrations general, and contractual defenses against adhesive contracts, reviewed are U.S. federal courts' attitudes toward certain consumer arbitration agreements including the class arbitration waiver. Moreover, several issues in AT&T case are examined for practical implications for consumer dispute resolution. All of these are expected to initiate further research to find some guidelines for the proper status and operation of consumer arbitration here in Korea.