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Accuracy Analysis of Target Recognition according to EOC Conditions (Target Occlusion and Depression Angle) using MSTAR Data (MSTAR 자료를 이용한 EOC 조건(표적 폐색 및 촬영부각)에 따른 표적인식 정확도 분석)

  • Kim, Sang-Wan;Han, Ahrim;Cho, Keunhoo;Kim, Donghan;Park, Sang-Eun
    • Korean Journal of Remote Sensing
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    • v.35 no.3
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    • pp.457-470
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    • 2019
  • Automatic Target Recognition (ATR) using Synthetic Aperture Radar (SAR) has been attracted attention in the fields of surveillance, reconnaissance, and national security due to its advantage of all-weather and day-and-night imaging capabilities. However, there have been some difficulties in automatically identifying targets in real situation due to various observational and environmental conditions. In this paper, ATR problems in Extended Operating Conditions (EOC) were investigated. In particular, we considered partial occlusions of the target (10% to 50%) and differences in the depression angle between training ($17^{\circ}$) and test data ($30^{\circ}$ and $45^{\circ}$). To simulate various occlusion conditions, SARBake algorithm was applied to Moving and Stationary Target Acquisition and Recognition (MSTAR) images. The ATR accuracies were evaluated by using the template matching and Adaboost algorithms. Experimental results on the depression angle showed that the target identification rate of the two algorithms decreased by more than 30% from the depression angle of $45^{\circ}$ to $30^{\circ}$. The accuracy of template matching was about 75.88% while Adaboost showed better results with an accuracy of about 86.80%. In the case of partial occlusion, the accuracy of template matching decreased significantly even in the slight occlusion (from 95.77% under no occlusion to 52.69% under 10% occlusion). The Adaboost algorithm showed better performance with an accuracy of 85.16% in no occlusion condition and 68.48% in 10% occlusion condition. Even in the 50% occlusion condition, the Adaboost provided an accuracy of 52.48%, which was much higher than the template matching (less than 30% under 50% occlusion).

Influencing Factors Analysis for the Number of Participants in Public Contracts Using Big Data (빅데이터를 활용한 공공계약의 입찰참가자수 영향요인 분석)

  • Choi, Tae-Hong;Lee, Kyung-Hee;Cho, Wan-Sup
    • The Journal of Bigdata
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    • v.3 no.2
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    • pp.87-99
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    • 2018
  • This study analyze the factors affecting the number of bidders in public contracts by collecting contract data such as purchase of goods, service and facility construction through KONEPS among various forms of public contracts. The reason why the number of bidders is important in public contracts is that it can be a minimum criterion for judging whether to enter into a rational contract through fair competition and is closely related to the budget reduction of the ordering organization or the profitability of the bidders. The purpose of this study is to analyze the factors that determine the participation of bidders in public contracts and to present the problems and policy implications of bidders' participation in public contracts. This research distinguishes the existing sampling based research by analyzing and analyzing many contracts such as purchasing, service and facility construction of 4.35 million items in which 50,000 public institutions have been placed as national markets and 300,000 individual companies and corporations participated. As a research model, the number of announcement days, budget amount, contract method and winning bid is used as independent variables and the number of bidders is used as a dependent variable. Big data and multidimensional analysis techniques are used for survey analysis. The conclusions are as follows: First, the larger the budget amount of public works projects, the smaller the number of participants. Second, in the contract method, restricted competition has more participants than general competition. Third, the duration of bidding notice did not significantly affect the number of bidders. Fourth, in the winning bid method, the qualification examination bidding system has more bidders than the lowest bidding system.

A Study on the Online Newspaper Archive : Focusing on Domestic and International Case Studies (온라인 신문 아카이브 연구 국내외 구축 사례를 중심으로)

  • Song, Zoo Hyung
    • The Korean Journal of Archival Studies
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    • no.48
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    • pp.93-139
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    • 2016
  • Aside from serving as a body that monitors and criticizes the government through reviews and comments on public issues, newspapers can also form and spread public opinion. Metadata contains certain picture records and, in the case of local newspapers, the former is an important means of obtaining locality. Furthermore, advertising in newspapers and the way of editing in newspapers can be viewed as a representation of the times. For the value of archiving in newspapers when a documentation strategy is established, the newspaper is considered as a top priority that should be collected. A newspaper archive that will handle preservation and management carries huge significance in many ways. Journalists use them to write articles while scholars can use a newspaper archive for academic purposes. Also, the NIE is a type of a practical usage of such an archive. In the digital age, the newspaper archive has an important position because it is located in the core of MAM, which integrates and manages the media asset. With this, there are prospects that an online archive will perform a new role in the production of newspapers and the management of publishing companies. Korea Integrated News Database System (KINDS), an integrated article database, began its service in 1991, whereas Naver operates an online newspaper archive called "News Library." Initially, KINDS received an enthusiastic response, but nowadays, the utilization ratio continues to decrease because of the omission of some major newspapers, such as Chosun Ilbo and JoongAng Ilbo, and the numerous user interface problems it poses. Despite these, however, the system still presents several advantages. For example, it is easy to access freely because there is a set budget for the public, and accessibility to local papers is simple. A national library consistently carries out the digitalization of time-honored newspapers. In addition, individual newspaper companies have also started the service, but it is not enough for such to be labeled an archive. In the United States (US), "Chronicling America"-led by the Library of Congress with funding from the National Endowment for the Humanities-is in the process of digitalizing historic newspapers. The universities of each state and historical association provide funds to their public library for the digitalization of local papers. In the United Kingdom, the British Library is constructing an online newspaper archive called "The British Newspaper Archive," but unlike the one in the US, this service charges a usage fee. The Joint Information Systems Committee has also invested in "The British Newspaper Archive," and its construction is still ongoing. ProQuest Archiver and Gale NewsVault are the representative platforms because of their efficiency and how they have established the standardization of newspapers. Now, it is time to change the way we understand things, and a drastic investment is required to improve the domestic and international online newspaper archive.

Development of remote control automatic fire extinguishing system for fire suppression in double-deck tunnel (복층터널 화재대응을 위한 원격 자동소화 시스템 개발 연구)

  • Park, Jinouk;Yoo, Yongho;Kim, Yangkyun;Park, Byoungjik;Kim, Whiseong;Park, Sangheon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.1
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    • pp.167-175
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    • 2019
  • To effectively deal with the fire in tunnel which is mostly the vehicle fire, it's more important to suppress the fire at early stage. In urban tunnel, however, accessibility to the scene of fire by the fire fighter is very limited due to severe traffic congestion which causes the difficulty with firefighting activity in timely manner and such a problem would be further worsened in underground road (double-deck tunnel) which has been increasingly extended and deepened. In preparation for the disaster in Korea, the range of life safety facilities for installation is defined based on category of the extension and fire protection referring to risk hazard index which is determined depending on tunnel length and conditions, and particularly to directly deal with the tunnel fire, fire extinguisher, indoor hydrant and sprinkler are designated as the mandatory facilities depending on category. But such fire extinguishing installations are found inappropriate functionally and technically and thus the measure to improve the system needs to be taken. Particularly in a double-deck tunnel which accommodates the traffic in both directions within a single tunnel of which section is divided by intermediate slab, the facility or the system which functions more rapidly and effectively is more than important. This study, thus, is intended to supplement the problems with existing tunnel life safety system (fire extinguishing) and develop the remote-controlled automatic fire extinguishing system which is optimized for a double-deck tunnel. Consequently, the system considering low floor height and extended length as well as indoor hydrant for a wide range of use have been developed together with the performance verification and the process for commercialization before applying to the tunnel is underway now.

A study on non-existence information of the information disclosure system : focused on the central administrative agencies (정보공개제도상의 정보부존재에 관한 고찰 중앙행정기관을 중심으로)

  • Kim, You-seung;Choi, Jeong Min
    • The Korean Journal of Archival Studies
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    • no.46
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    • pp.153-187
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    • 2015
  • This study aims to discuss issues about non-existent information of the information disclosure system and to provide alternative strategies for the issues. For the theoretical discussion it reviews the definitions and standards of non-existent information and analyzes legal aspects and statistical changes of non-existent information. Furthemore, in order to discuss a current status and problems of non-existent information at the central administrative agencies, it analyzes the cases of the non-existent information notification. According to analysis results, non-existent information status of the surveyed institutions is a total of 4,421 cases for three years and it shows the continuous increasing trend year after year. The number of institutions that have the number of non-existent information equal to the number of nondisclosures or over it reached about 40%. It means excluding non-existent information from the reasons of nondisclosure influenced disclose rates and nondisclosure rates of many agencies. In the type analysis of the non-existent information reasons, the most main reason, the case of not producing or receiving the requested information by public institutions takes over 75% among the whole reasons. The next reason is the case of collecting or processing information takes over 7-10%. This study found the operational issues, as analyzing notifications of non-existent information. The operational issues are 1) the incomplete explanation of non-existent information, 2) the unclear scope of the collection and processing, 3) the problem of the transfer processing, and 4) the problem of recording management. Therefore, this study suggested some improvements of the perspective and the technical and procedural aspects. First, information disclosure issues including non-existent information are to be understood as an extension of records management. Second, disclosure service should improve overall based on advanced understanding. Third, the management procedures of non-existent information should be improved. Fourth, specific guidelines for handling non-existent information should be developed.

Current Status and Future Development Direction of University Archives' Information Services : Based on the Interview with the Archives' Staff (대학기록관 기록정보서비스의 현황과 발전 방안 실무자 면담을 중심으로)

  • Lee, Hye Kyoung;Rieh, Hae-Young
    • The Korean Journal of Archival Studies
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    • no.40
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    • pp.131-180
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    • 2014
  • Various theoretical studies have been conducted to activate university archives, but the services provided currently in the field haven't been much studied. This study aims to investigate the usage and users of the domestic university archives, examine the types of the archival information services provided, understand the characteristics and limitations of the services, and suggest the development direction. This study set 3 objectives for the research. First, Identify the users of the university archives, the reason of the use, and the kinds of archival materials used. Second, the kinds of services and programs the university archives provide to the users. Third, the difficulties the university archives face to execute information services, the plans they consider in the future, and the best possible direction to prove the services. The authors of the study determined to apply interviews with the staffs at university archives to identify the current status of the services. For this, the range of the services offered in the field of university archives was defined first, and then, key research questions were composed. To collect valid data, authors carried out face to face interviews and email/phone interviews with the staff of 12 university archives, as well as the investigation of their Web sites. The collected data were categorized by the topic of the interview questions for analysis. By analyzing the data, some useful information was yielded including the demographic information of the research participants, the characteristics of the archives' users and requests, the types and activities of the services the university archives offered, and the limitations of archival information services, the archives' future plans, and the best possible development direction. Based on the findings, this study proposed the implications and suggestions for archival information services in university archives, in 3 domains as follows. First, university archives should build close relationship with internal university administrative units, student groups, and faculty members for effective collection and better use of archives. Second, university archives need to acquire both administrative records by transfer and manuscripts and archives by active collection. Especially, archives need to try to acquire unique archives of the universities own. Third, the archives should develop and provide various services that can elevate the awareness of university archives and induce more potential users to the archives. Finally, to solve the problems the archives face, such as the lack of the understanding of the value of the archives and the shortage of the archival materials, it was suggested that the archivists need to actively collect archival materials, and provide the valuable information by active seeking in the archives where ever it is needed.

Disaster Risk Assessment using QRE Assessment Tool in Disaster Cases in Seoul Metropolitan (서울시 재난 사례 QRE 평가도구를 활용한 재난 위험도 평가)

  • Kim, Yong Moon;Lee, Tae Shik
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.1
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    • pp.11-21
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    • 2019
  • This study assessed the risk of disaster by using QRE(Quick Risk Estimation - UNISDR Roll Model City of Basic Evaluation Tool) tools for three natural disasters and sixteen social disasters managed by the Seoul Metropolitan Government. The criteria for selecting 19 disaster types in Seoul are limited to disasters that occur frequently in the past and cause a lot of damage to people and property if they occur. We also considered disasters that are likely to occur in the future. According to the results of the QRE tools for disaster type in Seoul, the most dangerous type of disaster among the Seoul city disasters was "suicide accident" and "deterioration of air quality". Suicide risk is high and it is not easy to take measures against the economic and psychological problems of suicide. This corresponds to the Risk ratings(Likelihood ranking score & Severity rating) "M6". In contrast, disaster types with low risk during the disaster managed by the city of Seoul were analyzed as flooding, water leakage, and water pollution accidents. In the case of floods, there is a high likelihood of disaster such as localized heavy rains and typhoons. However, the city of Seoul has established a comprehensive plan to reduce floods and water every five years. This aspect is considered to be appropriate for disaster prevention preparedness and relatively low disaster risk was analyzed. This corresponds to the disaster Risk ratings(Likelihood ranking score & Severity rating) "VL1". Finally, the QRE tool provides the city's leaders and disaster managers with a quick reference to the risk of a disaster so that decisions can be made faster. In addition, the risk assessment using the QRE tool has helped many aspects such as systematic evaluation of resilience against the city's safety risks, basic data on future investment plans, and disaster response.

The Effective Approach for Non-Point Source Management (효과적인 비점오염원관리를 위한 접근 방향)

  • Park, Jae Hong;Ryu, Jichul;Shin, Dong Seok;Lee, Jae Kwan
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.140-146
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    • 2019
  • In order to manage non-point sources, the paradigm of the system should be changed so that the management of non-point sources will be systematized from the beginning of the use and development of the land. It is necessary to change the method of national subsidy support and poeration plan for the non-point source management area. In order to increase the effectiveness of the non-point source reduction project, it is necessary to provide a minimum support ratio and to provide additional support according to the performance of the local government. A new system should be established to evaluate the performance of non-point source reduction projects and to monitor the operational effectiveness. It is necessary to establish the related rules that can lead the local government to take responsible administration so that the local governments faithfully carry out the non-point source reduction project and achieve the planned achievement and become the sustainable maintenance. Alternative solutions are needed, such as problems with the use of $100{\mu}m$ filter in automatic sampling and analysis, timely acquisition of water sampling and analysis during rainfall, and effective management of non-point sources network operation management. As an alternative, it is necessary to consider improving the performance of sampling and analysis equipment, and operate the base station. In addition, countermeasures are needed if the amount of pollutant reduction according to the non-point source reduction facility promoted by the national subsidy is required to be used as the development load of the TMDLs. As an alternative, it is possible to consider supporting incentive type of part of the maintenance cost of the non-point source reduction facility depending on the amount of pollutants reduction.

Study on improvement of USLE P factor considering topography and cultivation method (지형 및 경작 방법을 반영한 범용토양유실량 산정공식 보전관리 인자 개선 연구)

  • Sung, Yunsoo;Lee, Gwanjae;Lee, Gwanjae;Han, Jeongho;Kim, Jonggun;Lim, Kyoung Jae;Kim, Ki Sung
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.163-172
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    • 2019
  • The USLE P factor is a factor that varies depending on how croplands are managed and cultivated. Previous studies tend to overestimate the amount of soil loss because the factor was estimated from the slope of the watershed rather than the estimate of each cultivated land. In addition, the accuracy of estimating the soil loss is decreasing due to the fact that the factor is calculated without considering various conditions of cultivated land defined by Wishmeier and Smith. In order to overcome these problems, the Ministry of Environment (MOE) has proposed to establish the topsoil notification and calculate the P factor according to the cultivation methods (e.g., tillage system, support practice). However, it is required to apply the conditions proposed in the United States to domestic circumstances as it is causing uncertainties. Thus, this study selected the watersheds where soil loss was serious (Haean, Jaun, Banbyeoncheon), measured the actual slopes and slope lengths, and examined the crop, tillage systems, and support practice for each cultivated land. The P factors were recalculated considering the actual conditions of cultivated land and compared to the factors proposed by the previous studies (MOE). As the result of the study, the P factors calculated based on the previous studies were 0.8 ~ 1.0 in three watersheds. On the other hand, it is confirmed that there is a significant difference between the factors notified by MOE and estimated by reflecting the topography and cultivation methods in this study. Therefore, it is considered that the research for developing the cultivation conditions to calculate the P factor suitable for the domestic environment should be continuously carried out.

Analysis of esthetic factors and evaluation of esthetic perception for maxillary anteriors of dental students (치과대학생의 상악 전치부의 심미적 요소 분석 및 인식도 평가)

  • Kim, Seon-Kyung;Kim, Ok-Su
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.2
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    • pp.118-126
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    • 2019
  • Purpose: This research is to investigate factors that affect dental aesthetics and analyze whether individual perception affects and difference of genders affects the esthetic factors. Materials and methods: Seventy dental students of Chonnam University aged from 25 to 35 years old without periodontal problems were included. Maxillary dental cast for participants were made, and standardized photo was taken with a digital camera. Maximum visual width and the position of gingival zenith of maxillary anterior teeth and maximum height of the maxillary central incisors were measured by a measurement program and the shape of central incisor was categorized. Questionnaire was conducted to evaluate esthetic perception. SPSS program was used to perform statistical analysis. Results: The average visual width ratio of right maxillary anteriors was 1.38:1:0.78 and 1.41:1:0.81 for the left which differ from the golden ratio. The width to height ratio for right and left central incisor was 0.84 and 0.83 respectively. The gingival zenith position was determined to be: mostly, central incisors and canines were located in the distal side, lateral incisors were located in the center. The visual width ratio of right maxillary anterior teeth, ratio of width to height of central incisor, gingival zenith position, crown morphology and amounts of gingival exposure upon smiling were not significantly different between genders, and facial patterns and these dental esthetic factors were not related to aesthetic perception. Conclusion: Even though participants had the visual width ratio of maxillary anteriors or ideal width to ideal height of central incisors that did not agree with the golden ratio, they had high satisfaction for dental esthetics. Esthetic perception depends more on subjective judgements of participants than objective indices.