• Title/Summary/Keyword: Problem areas

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Structural Segmentation for 3-D Brain Image by Intensity Coherence Enhancement and Classification (명암도 응집성 강화 및 분류를 통한 3차원 뇌 영상 구조적 분할)

  • Kim, Min-Jeong;Lee, Joung-Min;Kim, Myoung-Hee
    • The KIPS Transactions:PartA
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    • v.13A no.5 s.102
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    • pp.465-472
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    • 2006
  • Recently, many suggestions have been made in image segmentation methods for extracting human organs or disease affected area from huge amounts of medical image datasets. However, images from some areas, such as brain, which have multiple structures with ambiruous structural borders, have limitations in their structural segmentation. To address this problem, clustering technique which classifies voxels into finite number of clusters is often employed. This, however, has its drawback, the influence from noise, which is caused from voxel by voxel operations. Therefore, applying image enhancing method to minimize the influence from noise and to make clearer image borders would allow more robust structural segmentation. This research proposes an efficient structural segmentation method by filtering based clustering to extract detail structures such as white matter, gray matter and cerebrospinal fluid from brain MR. First, coherence enhancing diffusion filtering is adopted to make clearer borders between structures and to reduce the noises in them. To the enhanced images from this process, fuzzy c-means clustering method was applied, conducting structural segmentation by assigning corresponding cluster index to the structure containing each voxel. The suggested structural segmentation method, in comparison with existing ones with clustering using Gaussian or general anisotropic diffusion filtering, showed enhanced accuracy which was determined by how much it agreed with the manual segmentation results. Moreover, by suggesting fine segmentation method on the border area with reproducible results and minimized manual task, it provides efficient diagnostic support for morphological abnormalities in brain.

Problems and Suggestions for Improvement Derived from an Analysis of the Work of the Urban & Residence Environment Improvement Project -Focused on the Establishment of Preparation Committee and Association Committee- (도시 및 주거환경정비사업의 업무분석을 통한 문제점과 개선 사항 -조합설립추진위원회와 조합설립 업무를 중심으로-)

  • Ryu, Han-Guk;Son, Bo-Sik
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.3
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    • pp.39-47
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    • 2010
  • The government has routinely made efforts to improve the living environment and infrastructure of less-developed areas through large area urban remodeling projects, which are in themselves attempts to overcome the disadvantages of piecemeal local area development. Such projects are very complex, and various stakeholders are involved. However, the data on such projects has not been well managed, and has not lent itself to being easily adopted to similar projects. In addition, there are numerous fragmented mega-projects that seem to be performed based on "rules of thumb" To address this issue, the work process of many urban and residence project types should be standardized otherwise the participants will be confused to work properly. In particular, typical residents who lack knowledge about building redevelopment, building remodeling, urban environment improvement projects, and the like think that it is difficult to establish the preparation committees and association committees for the projects. Therefore, we examined previous researches related to the urban and building renovation to solve the prescribed present problems. This paper presents the three necessary research performances: first, we analyzed the administrative work process in the related laws; second, we examined the practical work process of the preparation committee and association committee stages; and finally we deduced the problem and presented the required improvements.

A study on selecting of Light Cutoff Panel depending on the installation condition using the lighting simulation (조명 시뮬레이션을 이용한 설치 환경별 차광판 선정에 관한 연구)

  • Park, Hyung-Kyu;Gu, Jin-Hoi;Lee, Kyu-Mok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.2
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    • pp.246-251
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    • 2016
  • The use of security lighting that emits spill light is considered a cause of light trespass problems in the residential areas. Therefore, a cutoff panel was installed as an alternative way to reduce light trespass. On the other hand, it has another problem in that it is less effective and is not good enough for aesthetics and safety. In this study, a light cutoff panel was designed and manufactured to reduce the light trespass, and the structure of a proper light cutoff panel was studied. Using a goniophotometer, the light distribution file (IES file) was extracted and the characteristics of light distribution were analyzed using the RELUX program. The results showed that the reduction of spilt light in the backward direction was decreased significantly for all types of light cutoff panels except the coated globe. In the case of a black powder coated light cutoff panel, the forward light caused by light reflected from the surface of the light cutoff panel was also reduced, which means that the black powder coated light cutoff panel is effective in the performance of light cutoff in the forward and backward directions. In addition, the coated glove increased the spilt light in the forward and backward directions because it reflects the upward light to go down. A 90 % accuracy between the measurement value of light trespass and the expected value of the light trespass was obtained from a simulation.

Energy Efficient Clustering Algorithm for Surveillance and Reconnaissance Applications in Wireless Sensor Networks (무선 센서 네트워크에서 에너지 효율적인 감시·정찰 응용의 클러스터링 알고리즘 연구)

  • Kong, Joon-Ik;Lee, Jae-Ho;Kang, Jiheon;Eom, Doo-Seop
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.11
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    • pp.1170-1181
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    • 2012
  • Wireless Sensor Networks(WSNs) are used in diverse applications. In general, sensor nodes that are easily deployed on specific areas have many resource constrains such as battery power, memory sizes, MCUs, RFs and so on. Hence, first of all, the efficient energy consumption is strongly required in WSNs. In terms of event states, event-driven deliverly model (i.e. surveillance and reconnaissance applications) has several characteristics. On the basis of such a model, clustering algorithms can be mostly used to manage sensor nodes' energy efficiently owing to the advantages of data aggregations. Since a specific node collects packets from its child nodes in a network topology and aggregates them into one packet to relay them once, amount of transmitted packets to a sink node can be reduced. However, most clustering algorithms have been designed without considering can be reduced. However, most clustering algorithms have been designed without considering characteristics of event-driven deliverly model, which results in some problems. In this paper, we propose enhanced clustering algorithms regarding with both targets' movement and energy efficiency in order for applications of surveillance and reconnaissance. These algorithms form some clusters to contend locally between nodes, which have already detected certain targets, by using a method which called CHEW (Cluster Head Election Window). Therefore, our proposed algorithms enable to reduce not only the cost of cluster maintenance, but also energy consumption. In conclusion, we analyze traces of the clusters' movements according to targets' locations, evaluate the traces' results and we compare our algorithms with others through simulations. Finally, we verify our algorithms use power energy efficiently.

A Study on the Development of an Effective GIS Data Maintenance Plan -Focused on the Applications for Municipalities (효율적인 GIS 데이터 유지관리 방안의 개발에 관한 연구 - 지방자치단체를 중심으로 -)

  • Kim, Seong-Hoon
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.1 s.31
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    • pp.89-96
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    • 2005
  • As the number of the municipalities which have finished the phase I of their GIS system development projects increases, it is very natural that GIS system operation and maintenance rather than development itself has been a more important concern for these municipalities. It seems to me that these phenomena will be amplified as time goes by, and this is the right time for a series of proper guidelines regarding the GIS system maintenance to be supplied to the related municipalities. The subject which is called as 'GIS maintenance' is surely a very comprehensive area. It has been also founded that the necessity is widely agreed among the concerned people working for the municipalities which have already finished their first GIS projects. Nevertheless, it has been investigated that the studies done up to now in this area is in a very infant state from the quality and also quantity points of views. This paper, therefore, makes one of the very initial trials for the systematical GIS maintenance. Among the areas of GIS maintenance, the GIS database maintenance has been selected as the first trial area because of its natural characteristics of the basic element composing IS(Information System). For this, the present conditions of a variety of municipalities have been investigated as far as GIS maintenance is concerned, and the results are analyzed to produce a series of useful outcomes in terms of facing problems and accompanied plans. For each problem, a solution is defined and for each solution a detailed action plan (item) is derived. For each of the two kinds of GIS data given which are the fundamental map and the underground facilities map, an effective GIS data maintenance plan is suggested for the concerned municipalities.

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Dynamic States Consideration for Next Hop Nodes Selection Method to Improve Energy Efficiency in LEAP based Wireless Sensor Networks (LEAP기반의 무선 센서 네트워크에서 가변적 상태를 고려한 에너지 효율적 다음 홉 노드 선택 기법)

  • Nam, Su-Man;Cho, Tae-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.23 no.6
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    • pp.558-564
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    • 2013
  • Wireless sensor networks (WSNs) contain limited energy resources and are left in open environments. Since these sensor nodes are self-operated, attacks such as sinkhole attacks are possible as they can be compromised by an adversary. The sinkhole attack may cause to change initially constructed routing paths, and capture of significant information at the compromised node. A localized encryption and authentication protocol (LEAP) has been proposed to authenticate packets and node states by using four types of keys against the sinkhole attack. Even though this novel approach can securely transmits the packets to a base station, the packets are forwarded along the constructed paths without checking the next hop node states. In this paper, we propose the next hop node selection method to cater this problem. Our proposed method evaluates the next hop node considering three factors (i.e., remaining energy level, number of shared keys, and number of filtered false packets). When the suitability criterion for next hop node selection is satisfied against a fix threshold value, the packet is forwarded to the next hop node. We aim to enhance energy efficiency and a detour of attacked areas to be effectively selected Experimental results demonstrate validity of the proposed method with up to 6% energy saving against the sinkhole attack as compared to the LEAP.

Urbanization and Urban Heat Island Analysis Using LANDSAT Imagery: Sejong City As a Case Study (LANDSAT 영상을 이용한 세종특별자치시의 도시화와 열섬현상 분석)

  • Kim, Mi-Kyeong;Kim, Sang-Pil;Kim, Nam-Hoon;Sohn, Hong-Gyoo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.3
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    • pp.1033-1041
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    • 2014
  • Rapid urbanization of Korea was an unprecedented example in the world and urban population increased significantly. As a result, unbalanced distribution of population is serious problem in Korea because approximately 50% of the population is concentrated in the capital area that is 10% of nation's territory, thereby occurring various urban problems including UHI. Hence, Sejong Special Autonomous City was inaugurated officially on 2 July 2012 in order to decentralize population of capital area and induce more balanced regional development. The Sejong City has been changed drastically over a period of years as developed practically since the late 2000's and is expected to have new problems of urbanization. The land cover change due to urbanization is the main cause of UHI that urban area is significantly warmer than its surrounding areas and UHI is not only affecting urban climate change but also natural environment. So the purpose of this research is to analyze level of urbanization and UHI effect and to provide the correlation analysis between Land Surface Temperature and spectral indices. To achieve this, satellite imagery from LANDSAT were used. NDVI, NDBI, and UI were calculated using red, near-infrared, mid-infrared ($0.63{\mu}m-1.75{\mu}m$) images and LST was retrieved utilizing thermal infrared ($10.4{\mu}m-12.5{\mu}m$) image. Based on each index and LST, Changes of NDVI, UI and UHI through TVI were analyzed in Sejong City. UHI effect increased around newly constructed multi-functional administrative city, the correlation between LST and NDVI was negative and UI was strong positive.

The Effect of Business Relationships on Conflict and Satisfaction in the Cosmetics Industry's Distribution Channel (코스메틱 산업에서의 유통경로상 거래관계가 갈등과 관계만족에 미치는 영향)

  • Park, Soo-Hong;Yang, Hoe-Chang;Sun, Il-Suck
    • Journal of Distribution Science
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    • v.13 no.6
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    • pp.79-86
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    • 2015
  • Purpose - The cosmetics industry is a traditional high value-added industry in terms of the domestic demand, small batch production systems, exclusive competition, and raw materials highly dependent on overseas countries as well as an oligopolistic market structure. However, new foreign brands and growing consumer awareness of inexpensive products, has triggered a shift. In line with changing lifestyles and the polarization of consumption, the industry faces a new market structure. Among its key characteristics is the cosmetics industry's numerous distribution channels (i.e., department stores, door-to-door sales, online shopping malls, brand shops, and discount stores). Therefore, the study of its distribution channels is essential. Research design, data, and methodology - The study analyzed channel distribution power divided into coercive and non-coercive power. The factors of coercive power included: unilateral request of an increase in commissions, interference in sales by taking advantage of a superior status, unilateral buck-passing at the time of a problem, unilateral request to stop sales activities, and a unilateral business contract; the factors of non-coercive power included favorable payment conditions, offers of various kinds of information, policy on commission reduction, pride in market entrance, and promotion support. In addition, the mediating variable "interdependence" was applied to the execution of department store (or mart) power and their shop conflicts and satisfaction to examine direct and indirect influential power. The methodology was a survey of managers of cosmetics shops in department stores (or marts). The questionnaire, based on a five-point Likert scale, included questions about basic personal information, execution of power, interdependence, conflict, and satisfaction. The study distributed 198 questionnaires and collected 131. Ten questionnaires with missing or hard to analyze data were excluded. Thus, 121 copies were analyzed. Results - According to the analysis, the execution of coercive power by department stores (or marts) did not affect interdependence, but the execution of non-coercive power did. Interdependence did not influence conflict, but did affect satisfaction. Additionally, the analysis revealed direct influential power: the execution of coercive power positively affected conflict and negatively influenced satisfaction; the execution of non-coercive power positively affected satisfaction. Conclusions - To offer suggestions for distribution business relations in the cosmetics industry, this study investigated how the execution of power by department stores (or marts) affected their shops. More specifically, it examined how much the execution of both coercive power and non-coercive power influenced conflict and satisfaction, and analyzed the mediating role of interdependence. In line with previous study results in various areas, coercive power was shown to be the source of conflict, leading to a decrease in satisfaction, whereas non-coercive power significantly positively influenced satisfaction. Moreover, non-coercive power increased interdependence, which led to greater satisfaction. As a result, interdependence had a mediating effect on non-coercive power and satisfaction. Based on the results, department stores (or marts) should look for improvements plans that increase interdependence. Such plans could alleviate conflict with the shops, increasing their satisfaction.

Analyzing Factors Influencing Purchasing Behavior of PB Eggs: Focusing on Eggs from Large Distribution Companies (계란식품PB 구매에 미치는 소비자 요인 분석:대형유통업체 계란상품을)

  • Kim, Jong-Jin;Shim, Kyu-Yeol;Kim, Mi-Song;Youn, Myoung-Kil
    • Journal of Distribution Science
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    • v.11 no.10
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    • pp.107-116
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    • 2013
  • Purpose - Eggs are nutritionally complete and one of the most popular natural foods. Moreover, the poultry industry is one of the important food industries. However, early industrialization of the poultry industry on its own did not lead to further development compared to other livestock industries. In this study, we investigate what factors influence consumers' behavior and how consumers' understanding of retail business affects their propensity to consume. This study is different from other studies as it analyzes how the brand names of manufacturers and distribution companies affect the purchasing characteristics or actual purchase behavior of consumers in order to suggest how these manufacturers and distribution companies can increase their competitiveness. Research design, data, methodology - This study conducted a survey of 250 randomly selected egg purchasers in discount stores from January to April 2013. Consumers' purchase tendencies were calculated through frequency analysis. This result was then utilized using cluster analysis to draw a conclusion about which purchase tendency influenced consumers buying three different brands of eggs or whether this tendency really affected consumers. As a result, the outcomes of Hypotheses 2 and 3 were not clear so we drew a conclusion with our analysis of Hypothesis 1. Results - While the outcomes of Hypotheses 2 and 3 did not clearly indicate whether purchasing tendencies affected consumers when buying eggs, our analysis of Hypothesis 1 indicated that consumers were affected by the quality of the eggs rather than exterior factors such as the brand name. Thus, we concluded that it is important to promote the excellence of the quality of the eggs. Usually firms buy eggs from farms and repackage them in order to sell them. In this sense, if consumers were aware of this egg production process, and eggs were fairly distributed to retailers, large retail PB businesses would also be able to enhance their competitiveness. Conclusions - The brand, packaging, retail outlet, and other external features influenced the purchase of eggs to a certain degree, while shelf life, grade of the eggs, cleanliness, and other intrinsic characteristics had more influence. In particular, shelf life was the most important factor influencing purchase. Consumers were influenced not only by intrinsic characteristics of the eggs but also by large-scale producers' brands. Consumers relied upon the brand despite reduced competition because they found it difficult to identify shelf life and/or cleanliness. Small businesses and/or large-scale retailers can remain competitive by maintaining the freshness and cleanliness of the eggs. Further studies need to investigate areas in which consumers' cognition of the product is poor and/or the purchase inclination with regard to less developed industries such as eggs. In this study, the greatest problem was that consumers did not consume in accordance with the current situation as consumers have preferred fresh and clean eggs for a long time compared to purchase decisions based on external brands and/or packaging.

Quantitative Assessment of Myocardial Infarction by In-111 Antimyosin Antibody (In-111-Antimyosin 항체를 이용한 심근경색의 정량적 평가)

  • Lee, Myung-Chul;Lee, Kyung-Han;Choi, Yoon-Ho;Chung, June-Key;Park, Young-Bae;Koh, Chang-Soon;Moon, Dae-Hyuk
    • The Korean Journal of Nuclear Medicine
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    • v.25 no.1
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    • pp.37-45
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    • 1991
  • Infarct size is a major determinant of prognosis after acute myocardial infarction. Up to date, however, clinically available tests to estimate this size have not been sufficiently accurate. Twelve lead electrocardiogram and wall motion abnormality measurement are not quantitative, and creatine phophokinase (CPK) measurement is inaccurate in the presence of reperfusion or right ventricular infarction. Methods have been developed to localize and size acute myocardial infarcts with agents that are selectively sequestered in areas of myocardial damage, but previously used agents have lacked sufficient specificity. Antibodies that bind specifically only to damaged myocardial cells may resolve this problem and provide an accurate method for noninvasively measuring infarct size. We determined the accuracy with which infarcted myocardial mass can be measured using single photon emission computed tomography (SPECT) and radiolabeled antimyosin antibodies. Seven patients with acute myocardial infarction and one stable angina patient were injected with 2 mCi of Indium-111 labeled antimyosin antibodies. Planar image and SPECT was performed 24 hours later. None of the patients had history of prior infarcts, and none had undergone reperfusion techniques prior to the study, which was done within 4 days of the attack. Planar image showed all infarct patients to have postive uptakes in the cardiac region. The location of this uptake correlated to the infarct site as indicated by electrocardiography in most of the cases. The angina patient, however, showed no such abnormal uptake. Infarct size was determined from transverse slices of the SPECT image using a 45% threshold value obtained from a phantom study. Measured infarct size ranged from 40 to 192 gr. There was significant correlation between the infarct size measured by SPECT and that estimated from serial measurements of CPK (r=0.73, p<0.05). These date suggest that acute myocardial infarct size can be accurately measured from SPECT Indium-111 antimyosin imaging. This method may be especially valuable in situations where other methods are unreliable, such as early reperfusion technique, right ventricular infarct or presence of prior infarcts.

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