• Proceedings of the Korea Information Processing Society Conference
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• 2003.11c
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• pp.1529-1532
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• 2003

최근 인터넷과 모바일 시스템이 급속히 발달함에 따라 이를 통하여 지리정보와 같은 공간데이터를 제공하는 서비스가 증가하였다. 이는 대용량 데이터에 대한 관리 및 빠른 처리와 급증하는 사용자에 대한 높은 동시처리량 및 높은 안정성을 요구하였고, 이를 해결하기 위하여 비공유 공간 데이터베이스 클러스터가 개발되었다. 비공유 공간 데이터베이스 클러스터는 고가용성을 위한 구조로서 문제가 발생할 경우 다른 백업노드가 대신하여 서비스를 지속시킨다. 그러나 기존의 비공유 공간 데이터베이스 클러스터는 클러스터 구성에 대한 회복을 위하여 로그를 계속 유지하므로 로그를 남기기 위해 보통의 질의처리 성능이 저하되었으며 로그 유지를 위한 비용이 증가하였다. 또한 노드단위의 로그를 갖기 때문에 클러스터 구성에 대한 회복이 직렬적으로 이루어져 고가용성을 위한 빠른 회복이 불가능 하였다. 따라서 본 논문에서는 비공유 공간 데이터베이스 클러스터에서 고가용성을 위한 병렬 회복 기법을 제안한다. 이를 위해 클러스터 구성에 대한 회복을 위한 클러스터 로그를 정의한다. 정의된 클러스터 로그는 마스터 테이블이 존재하는 노드에서 그룹내 다른 노드가 정지된 것을 감지할 때 남기기 시작한다. 정지된 노드는 자체회복을 마친 후 클러스터 구성에 대한 회복을 하는 단계에서 존재하는 복제본 테이블 각각에 대한 클러스터 로그를 병렬적으로 받아 회복을 한다. 따라서 정지된 노드가 발생할 경우에만 클러스터 로그를 남기므로 보통의 질의처리의 성능 저하가 없고 클러스터 로그 유지 비용이 적으며, 클러스터 구성에 대한 회복시 테이블단위의 병렬적인 회복으로 대용량 데이터인 공간데이터에 대해 빠르게 회복할 수 있어 가용성을 향상시킨다.들을 문법으로 작성하였으며, PGS를 통해 생성된 어휘 정보를 가지고 스캐너를 구성하였으며, 파싱테이블을 가지고 파서를 설계하였다. 파서의 출력으로 AST가 생성되면 번역기는 AST를 탐색하면서 의미적으로 동등한 MSIL 코드를 생성하도록 시스템을 컴파일러 기법을 이용하여 모듈별로 구성하였다.적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는

• The KIPS Transactions:PartC
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• v.12C no.3 s.99
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• pp.429-436
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• 2005

A mobile ad hoc network (MANET) is a collection of mobile nodes without any fixed infrastructure or my form of centralized administration such as access points and base stations. The ad hoc on-demand distance vector routing (AODV) protocol is an on-demand routing protocol for MANETs, which is one of the Internet-Drafts submitted to the Internet engineering task force (IETF) MANET working group. This paper proposes a new multipath routing protocol called maximally disjoint multipath AODV (MDAODV), which exploits maximally node- and link-disjoint paths and outperforms the conventional multipath protocol based on AODV as well as the basic AODV protocol. The key idea is to extend only route request (RREQ) message by adding source routing information and to make the destination node select two paths from multiple RREQs received for a predetermined time period. Compared to the conventional multipath routing protocol, the proposed MDAODV provides more reliable and robust routing paths and higher performance. It also makes the destination node determine the maximally node- and link-disjoint paths, reducing the overhead incurred at intermediate nodes. Our extensive simulation study shows that the proposed MDAODV outperforms the conventional multipath routing protocol based on AODV in terms of packet delivery ratio and average end-to-end delay, and reduces routing overhead.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.148-154
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• 2020

This study examines room assignments to improve accessibility in a university dormitory depending on the student grade, taking into account frequency of using a certain common space. An integer programming model is presented to minimize the total moving distance from the common space to the students' rooms for accessibility. The model also constrains the maximum capacity of a room, and disallows different grade students to be assigned to the same room. This model is similar to a facility location problem used widely in the supply chain management field. Applying our optimization model to a small group at the dormitory of Unversity A as the case study, our results indicate that lower grade students are assigned rooms closer to the common space due to their higher frequency of using that space to guarantee high accessibility. Moreover, if higher grade students are prioritized to select their rooms, we suggest an objective function that imposes a penalty in cases when lower grade students select rooms with priority. Based on the results obtained, we propose assigning rooms to students in a dormitory by considering their complex requirements and convenience to use the common space.

• Research in Plant Disease
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• v.24 no.3
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• pp.182-192
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• 2018

Since fire blight (Erwinia amylovora) firstly broke out at mid-Korea in 2015, it is necessary to investigate potential spread of the invasive pathogen. To speculate environmental factors of fireblight epidemic based on disease triangle, a fire blight predicting program, MARYBLYT, was run with the measured meteorological data in 2014-2017 and the projecting future data under RCP8.5 scenario for 2020-2100. After calculating blossom period of Singo pear from phenology, MARYBLYT was run for blossom blight during the blossom period. MARYBLYT warned "Infection" blossom blight in 2014-15 at Anseong and Cheonan as well as Pyungtak and Asan. In addition, it warned "Infection" in 2016-17 at Naju. More than 80% of Korean areas were covered "Infection" or "High", therefore Korea was suitable for fire blight recently. Blossom blight for 2020-2100 was predicted to be highly fluctuate depending on the year. For 80 years of the future, 20 years were serious with "Infection" covered more than 50% of areas in Korea, whereas 8 years were not serious covered less than 10%. By comparisons between 50% and 10% of the year, temperature and amount of precipitation were significantly different. The results of this study are informative for policy makers to manage the alien pathogen.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.57-63
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• 2012

This study was carried our to examine the genetic relationship of 13 commercial turfgrass cultivars using Random Amplified Polymorphic DNA to provide genetic informations more efficient golf course management. Analysis of 56 random hexamer primers generated 13 to 54 polymorphic bands among the 13 cultivars with an average of 30.7 bands per primer. The results of cluster analysis based on RAPDs revealed that three major variety groups: Group I - 'Shadow II', 'Aurora Gold', 'Little Bighorn Blue', 'PennA-1', and 'PennA-4'; Group II - 'Midnight II', 'Prosperity', 'Moon light SLT', 'Bright star SLT', and 'Silver dollar'; and Group III - 'Olympic Gold', 'Silver Star', and 'Tar Heel II'. The genetic similarity coefficients among 13 turfgrass cultivars ranged from 0.039 to 1.0 with highest coefficient in Group III. Studies on morphological characters and the effective molecular markers such as sequence characterized amplified regions are further needed to identify relationships and genetic diversities within species and among species.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.855-868
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• 2014

Synthetic agro-chemicals have been widely used to control diseases on paprika but these days negative attention has been increasing to use of them because of several adverse effects. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ1 isolated in this research belongs to a group of Serratia marcescens. Specially, 16S rDNA gene sequence of YKJ1 showed 99% of sequence similarity with S. marcescens. Observation through the optical microscope revealed that YKJ1 suppressed the spore germination and the hyphal growth of pathogens. YKJ1 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. S. marcescens found in this study call as S. marcescens-YKJ1 and it may be valuable as one of biological control agents against major diseases of paprika in the future even though it is require to be tested with more study on field test.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.119-166
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• 2019

The risk of electromagnetic field(EMF) from power lines has been heavily disputed whenever high-voltage power line towers were built in South Korea. Local communities and civic groups had regarded burying the lines in the ground as an alternative to building power line towers. In 2014, however, when an elementary school science teacher reported the results of EMF measurements over the underground power lines to the Asian Citizens' Center for Environment and Health (ACCEH), the risk controversy over underground power lines took a whole new turn. The level of EMF from underground power lines turned out to be higher, and therefore more harmful than that from power line towers. In the debates that took place from then on over the EMF risk, ACCEH and NIER(National Institute of Environmental Research) presented conflicting topographies of EMF risk. This paper examines measuring practices of ACCEH and NIER by analyzing the measuring sites, measuring devices, and measuring heights chosen by each organization. This paper further examines how ACCEH and NIER mobilized various standards(EMF exposure limit, measurement guideline, categorization of carcinogens) differently. This controversy on the EMF from underground power lines of Seoul has raised concerns on the non-thermal effects of EMF in the long-term exposure and has led people to question whether burying the power lines is the safe alternative to building power line towers. Furthermore, this suggests conflicting answers on whether Seoul, where 90 % of transmission lines were already buried, is a safely managed place or not.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.2
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• pp.103-112
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• 2010

In sensor networks, because sensors are deployed in an unprotected environment, they are prone to be targets of compromise attack, If the number of compromised nodes increases considerably, the key management in the network is paralyzed. In particular, compromise of Cluster Heads (CHs) in clustered sensor networks is much more threatening than that of normalsensors. Recently, rekeying schemes which update the exposed keys using the keys unknown to the compromised nodes are emerging. However, they cause some security and efficiency problems such as single group key employment in a cluster, passive eviction of compromised nodes, and excessive communication and computation overhead. In this paper, we present a proactive rekeying scheme using renewals of duster organization for clustered sensor networks. In the proposed scheme, each sensor establishes individual keys with neighbors at network boot-up time, and these keys are employed for later transmissions between sensors and their CH. By the periodic cluster reorganization, the compromised nodes are expelled from network and the individual keys employed in a cluster are changed continuously. Besides, newly elected CHs securely agree a key with sink by informing their members to sink, without exchangingany keying materials. The simulation results shows that the proposed scheme remarkably improves the confidentiality and integrity of data in spite of the increase of compromised nodes. Also, they show that the proposed scheme exploits the precious energy resource more efficiently than SHELL.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.5
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• pp.159-173
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• 2019

The purpose of this study is to examine the effect of service quality of banks on customer satisfaction and recommendation intention through empirical analysis. In particular, the focus was on the differences of the causal effect between PB(Private Banking) customers and regular customers. For this study, two groups were surveyed and 428 valid questionnaires were analyzed. The hypothesis was tested with a structural equation model using AMOS 23.0. As a result, empathy, reliability and tangibles of bank service quality had a positive(+) effect on customer satisfaction. However, responsiveness and assurance were not statistically significant. On the other hand, customer satisfaction has a positive effect on recommendation intention. This study was conducted to compare the two groups, PB customers and regular customers, and found a significant difference. In the PB customers group, tangibles had a positive effect on customer satisfaction, but no other factors were supported. On the other hand, in the regular customers group, empathy and reliability had a positive effect on customer satisfaction while responsiveness, assurance, and tangibles were not supported. Customer satisfaction were analyzed to have a positive influence on recommendation intention in both groups. These findings are academically significant by applying the SERVQUAL factors to banking services and revealing the differences between the PB customers and regular customers. In practice, it is meaningful in that it provided banks with the insights needed for future segmentation and management of customer groups.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.349-355
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• 2021

This study applied aquatic and land-based exercises to breast cancer patients for comparative analysis and elucidation of their effects on the rehabilitation of cancer patients. Participants included 40 breast cancer patients who were divided into two groups: 20 participants in the experimental group using aquatic exercise and 20 participants in the control group using land-based exercise. After the addition of aquatic or land-based exercises five times per week for eight weeks, differences in each group's shoulder and pulmonary functions as well as their quality of life were compared and analyzed. The results showed a statistically significant difference (p<.001) for shoulder dysfunction, with the experimental group showing a greater improvement than the comparison group. Statistically significant differences (p<.05 and p<.001, respectively) were also observed for forced vital capacity (FVC) and forced expiratory volume in one second (FEV1), with the experimental group showing greater improvements. Finally, a statistically significant difference (p<.001) was observed for change in the quality of life, with greater improvements in the experimental group than in the control group. The results of further research in this field are expected to indicate the most efficient method for the recovery and management of physical, psychological, and social health impacts of breast cancer on patients. Furthermore, the research aims to provide fundamental resources for breast cancer rehabilitation in South Korea by conducting studies on patients with lung cancer or colorectal cancer and the application of various aquatic exercise methods.