• Journal of Food Hygiene and Safety
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• v.33 no.1
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• pp.23-30
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• 2018

The purpose of this research was to introduce network analysis method for analyzing pesticide residues in incongruity commercial agricultural commodities. Based on the "results in pesticide residues on incongruity commercial agricultural commodities" on "Guidelines for food safety management 2017", we used centrality analysis for pesticide residues via degree, closeness and betweenness centrality measurement. In case of degree centrality result, chlorpyrifos and diazinon were the most highly "connected node" in pesticide network. For the closeness centrality result, the most pesticides showed the similar closeness trend except for 19 species of pesticides. Fludioxonil and chlorpyrifos are recognized as the "bridge" of pesticides network with their high betweenness centrality. The results of network analysis show the "relation" data, which could not represent through out the conventional statistical analysis, among the pesticide residues. We hope that the network analysis method will be appropriate and precise tool for analyzing pesticide residues via elaboration and optimization.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.10
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• pp.293-302
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• 2016

Since the electricity is produced and consumed simultaneously, predicting the electric load and securing affordable electric power are necessary for reliable electric power supply. In particular, a university campus is one of the highest power consuming institutions and tends to have a wide variation of electric load depending on time and environment. For these reasons, an accurate electric load forecasting method that can predict power consumption in real-time is required for efficient power supply and management. Even though various influencing factors of power consumption have been discovered for the educational institutions by analyzing power consumption patterns and usage cases, further studies are required for the quantitative prediction of electric load. In this paper, we build an electric load forecasting model by implementing and evaluating various machine learning algorithms. To do that, we consider three building clusters in a campus and collect their power consumption every 15 minutes for more than one year. In the preprocessing, features are represented by considering periodic characteristic of the data and principal component analysis is performed for the features. In order to train the electric load forecasting model, we employ both artificial neural network and support vector machine. We evaluate the prediction performance of each forecasting model by 5-fold cross-validation and compare the prediction result to real electric load.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.2
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• pp.287-303
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• 2018

In recent years, the occurrence of ground subsidence phenomenon is frequent in Korea. The Korean government has enacted a special law on underground safety and the law will be enforced from January 1, 2018. Under this new law, underground excavation should be assessed for underground safety impacts. After excavation construction, periodic geophysical surveys should be conducted to investigate the occurrence of underground cavities. When underground cavities were discovered, the underground safety was assessed through numerical analysis. However, it is controversial because the method of numerical modeling the discovered underground cavity is due to be established. In this study, the effect of the depth of the underground cavity from the shape of the underground cavity to the underground cavity was studied using a continuum analysis program. In this study, a method to reflect the shape of the underground cavity to the numerical modeling is presented. The relationship between the shape and depth of the underground cavity, and the factor of safety calculated by the shear strength reduction method (SSR) is presented. The results of this study are expected to form the basic data on underground safety impact assessment.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.09a
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• pp.370-380
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• 1995

선형계획법의 해법으로 최근에는 내부점기법(Interior Point Method)가 관심 을 끌고 있다. 이 내부점 기법은 계산복잡도 뿐만 아니라 수행속도면에서도 우수한 결과를 보이고 있다. 이 방법은 매 회 대칭양정치(Symmetric Positive Definite)인 선형시스템을 풀어야 하는데 이 과정이 전체 내부점 수 행시간의 80-90%를 차지한다. 따라서 내부점 기법의 수행속도는 대칭양정치 인 선형시스템을 효율적으로 푸는 방법에 달려 있다. 대칭양정치인 선형시스 템을 풀기 위해서는 상하분해를 이용하게 되는 데 가우스소거를 이용해서 상하 분해를 하는 경우 매 단계에서 행렬의 모든 요소를 가지고 있을 필요 가 없다. 행렬의 모든 요소에 대한 정보를 동시에 필요로 하지 않는다. 즉, 현 단계에서 가우스소거와 관련된 열들에 대한 정보만 있으면 상하 분해가 가능하고 이러한 개념을 이용한 방법이 프런탈방법이다. 프런탈 방법은 대형 선형계획 문제를 풀기에 유리하다는 장점이 있다. 이러한 프런탈 방법을 확 장해서 동시에 여러 개의 프런탈을 계산하는 방법이 멀티프런탈방법이다. 이 방법은 알고리듬 자체가 병렬처리에 적합하기 때문에 병렬처리와 관련해서 도 많은 연구가 수행되고 있다. 본 연구에서는 삭제나무(Elimination Tree)를 이용한 프런탈 방법과 프런탈방법에 슈퍼노드의 개념을 도입한 슈퍼노들 프 런탈방법등에 대해서 이제까지의 연구 현황을 알아보고 프런탈방법에 적합 하고 효율적인 자료 구조와 멀티프런탈 방법에 적용 가능한 병렬알고리듬에 대하여 연구하고자 한다. 본 연구결과 기대효과로는 프런탈 방법에 적합하고 효율적인 자료 구조와 멀티프런탈 방법에 적용 가능한 병렬알고리듬을 개발 함으로써 내부점 선형계획법의 수행속도의 개선에 도움이 될 것이다.성요소들을 제시하였다.용자 만족도가 보다 높은 것으 로 나타났다. 할 수 있는 효율적인 distributed system를 개발하는 것을 제시하였다. 본 논문은 데이타베이스론의 입장에서 아직 정립되어 있지 않은 분산 환경하에서의 관계형 데이타베이스의 데이타관리의 분류체계를 나름대로 정립하였다는데 그 의의가 있다. 또한 이것의 응용은 현재 분산데이타베이스 구축에 있어 나타나는 기술적인 문제점들을 어느정도 보완할 수 있다는 점에서 그 중요성이 있다.ence of a small(IxEpc),hot(Tex> SOK) core which contains two tempegatlue peaks at -15" east and north of MDS. The column density of HCaN is (1-3):n1014cm-2. Column density at distant position from MD5 is larger than that in the (:entral region. We have deduced that this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.업순서들의 상관관계를 고려하여 보다 개선된 해를 구하기 위한 연구가 요구된다. 또한, 준비작업비용을 발생시키는 작업장의 작업순서결정에 대해서도 연구를 행하여, 보완작업비용과 준비비용을 고려한 GMMAL 작업순서문제를 해결하기 위한 연구가 수행되어야 할 것이다.로 이루어 져야 할 것이다.태를 보다 효율적으로 증진시킬 수 있는 대안이 마련되어져야 한다고 사료된다.$\ulcorner$순응$\lrcorner$<

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.181-196
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• 2019

Floods can be caused by a variety of factors, and the main cause of floods is the exceeding of urban drainage system or river capacity. In addition, rainfall frequently occurs that causes large watershed runoff. Since the existing methodology of preparing for flood risk map is based on hydraulic and hydrological modeling, it is difficult to analyse for a large area because it takes a long time due to the extensive data collection and complex analysis process. In order to overcome this problem, this study proposes a methodology of mapping for flood vulnerable area that considered the surface runoff mechanism. This makes it possible to reduce the time and effort required to estimate flood vulnerabilities and enable detailed analysis of large areas. The target area is Seoul, and it was confirmed that flood damage is likely to occur near selected vulnerable areas by verifying using 2×2 confusion matrix and ROC curve. By selecting and prioritizing flood vulnerable areas through the surface runoff mechanism proposed in this study, the establishment of systematic disaster prevention measures and efficient budget allocation will be possible.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.51-63
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• 2013

Recently with base apply MANET with the application for the service discovery and delivery which are various techniques are being proposed the result of such MANET base research techniques from actual inside. This dissertation proposes T-Chord(Trustworthy-based Chord) Ring system for MANET to guarantees from such requirements. T-Chord Ring system in order to manage Efficiently the services which the mobile nodes provide is the service discovery system which uses P2P overlay network Technique in mobile environment. The system which is proposed MANET communications in order to accomplish a service discovery operation with physical network class and logical network class will be able to minimize problems from about MANET service discoveries, and uses the dispersive hash table technique for a service discovery and effectiveness of service discovery improves and will be able to guarantee the expandability of network size. The mobile nodes(mobile device) have a mobility from MANET and operate with service request node, service provide node and service transmit node. The mobile nodes will be able to elect cluster header using Trustworthy that was evaluated service request, provision and delivery in each other. The system which is proposed a service discovery and a delivery efficiently will compose the cluster head which will grow of P2P overlay networks and will be able to accomplish. The system which proposes from dissertation is composed of Trustworthy evaluations of MANET mobile nodes, service information collection which is dispersed and P2P overlay networks that composed of Chord algorithm modules which provide O(Log N) efficiencies. The system comparison evaluation analyzes an efficiency from the expandability side of effectiveness and the network of service discovery technique and the service discovery message over head, service discovery and delivery of former times and service discovery and delivery is excellent gives proof from MANET.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.45-52
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• 2019

As international criteria and standards are required in the fields of design and construction, landscape performance must also be considered not only for the value of the landscape but also for providing quality assurance and sustainability. Given the lack of research on landscape performance, the present research was purposed to analyze the importance of potential assessment categories and items using an analytical network process. A list of assessment items, which is composed of 20 items and 6 categories, was derived through a literature review and a preliminary survey of 11 landscape professionals. An ANP model was established and a survey was conducted among 30 landscape practitioners to determine the weight of priorities considering the criteria. The results of ANP showed that the categories of site selection, preservation and health, and convenience had high priorities while materials had the lowest importance score. For the assessment items, a monitoring plan was the highest importance, followed by cultural/ historic preservation, management cost reduction, and natural ground areas. Despite the difficulties in quantifying landscape achievements, most respondents agreed that there needs to be an evaluation system for landscape performance in order to assure the quality and sustainability of landscape development. More research and discussion are needed to develop an assessment system for landscape performance that is applicable to Korean context.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.3
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• pp.78-87
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• 2013

NAND flash memory has been widely used as a storage medium in mobile devices, PCs, and workstations due to its advantages such as low power consumption, high performance, and random accessability compared to a hard disk drive. However, NAND flash cannot support in-place update so that it is mandatory to erase the entire block before overwriting the corresponding page. In order to overcome this drawback, flash storages need a software support, named Flash Translation Layer. However, as the high performance mass NAND flash memory is getting widely used, the size of mapping tables is increasing more than the limited DRAM size. In this paper, we propose an adaptive mapping information caching algorithm based on page mapping to solve this DRAM space shortage problem. Our algorithm uses a mapping information caching scheme which minimize the flash memory access frequency based on the analysis of several workloads. The experimental results show that the proposed algorithm can increase the performance by up to 70% comparing with the previous mapping information caching algorithm.

• Investigative Magnetic Resonance Imaging
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• v.12 no.2
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• pp.142-147
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• 2008

Purpose : By using the micro-imaging unit modified from NMR spectrometer, the high resolution MRI protocols of finer than 100 micron in 5 minutes, is sought for mouse, which plays a central role in animal studies Materials and Methods : C57BL/6 mouse, lighter than 50 gram, is used for the experiments. The superconducting magnet is vertical type with 89 mm inner diameter at 4.9 Tesla. The diameter of rf-coil is 30 mm. Mostly used techniques are the fast spin echo and the gradient echo pulse sequence. Results : For 2D images, proton density and T2 weighted images are obtained and their optimum experimental variables were sought. Minute structure of mouse brain can be recognized and 3D brain image is also obtained additionally. 3D image will be useful particularly for the dynamic contrast study using various contrast agents. Conclusion : Like the case of human and other small animals, the high resolution of mouse brain is enough to recognize the minute structure of it. Recently, similar studies are reported domestically, but it seems only a beginning stage. Due to easiness of breeding/control, mouse MRI study will soon play a vital part in brain study.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.163-176
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• 2007

Landslides which is one of the major natural hazard is defined as a mass movement of weathered material rock and debris due to gravity and can be triggered by complex mechanism. It causes enormous property damages and losses of human lift directly and indirectly. In order to mitigate landslide risk effectively, a new method is required to develope for better understanding of landslide risk based on the damaged cost produce, investment priority data, etc. In this study, we suggest a new evaluation method for slope stability using risk analysis. 30 slopes including 10 stable slopes, 10 slopes of possible failure and 10 failed slopes along the national and local roads are examined. Risk analysis comprises the hazard analysis and the consequence analysis. Risk scores evaluated by risk analysis show very clear boundaries for each category and are the highest for the failed slopes and the lowest for the stable slopes. The evaluation method for slope stability suggested by this research may define the condition and stability of slope more clearly than other methods suggested by others.