• Composites Research
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• v.31 no.6
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• pp.304-310
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• 2018

Autoclave process has been remaining as one of the most robust and stable process in fabricating structural composite part of aerospace industry. It has lots of advantages, however exhibits some disadvantages or limitations in capital investment and operation. Recently, there have been various Out-of-Autoclave process being researched and developed to overcome those limitations. In this study, laminate specimens were fabricated using LCM (Liquid Composite Molding) process, regarded as one of potential OoA process. DB (Double bagging), CAPRI (Controlled Atmospheric Pressure Resin Infusion), VAP (Vacuum Assisted Process) and Autoclave process were used for laminate specimens. Void content, Thickness, Tg (Glass Transition Temperature), ILSS (Interlaminar Shear Strength) and Flexural strength properties were evaluated for comparison. It is verified that Autoclave based specimen has uniform thickness distribution, the lowest void content and outstanding mechanical properties. And, CAPRI based specimen exhibits relatively good physical and mechanical properties over DB and VAP based specimen and comparable mechanical properties with autoclave based specimen.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.1-11
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• 2021

As the aging of large domestic SOC facilities accelerates, facility maintenance is also changing from safety evaluation based on the current condition to performance-oriented preventive and preemptive maintenance based on the prediction of the level of future obsolescence. In particular, in the case of bridges, class 1 and 2 bridges are systematically managed along with many studies, but for small and medium-sized class 3 bridges there is no collection and utilization of historical data presenting performance degradation during their service life. Therefore, in this study, 3D model-based demonstration DB system was designed and developed to intuitively check the damage change rate at the damage location by registering the maintenance history by life cycle for each member's exterior damage in the 3D bridge object and to enable API-based comprehensive performance evaluation.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.3
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• pp.57-69
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• 2014

As of 2013, Korean population density is 505 persons per $1km^2$ and is ranked 3rd place in the most densely populated countries exception of city-states. It shows clearly the population is concentrated in the city area. To fulfil this urban concentration population demand, the enlargement and complexation of buildings, subway and other underground spaces connection tendency has been intensified, and it is need to construct the indoor spatial information DB as well as the accurate indoor surveying DB to promote people's safety and social welfare. In this study, Sadang station and Incheon National Airport were aimed for the construction of Wi-Fi AP location DB and RadioMap DB by collecting the indoor AP raw datas by using mobile device and those collected results were ran through the process of verification, supplementation, and analyzation. To evaluate the performance of constructed DB, 10 points in Incheon Airport- 3rd flr in block A, and 9 points in Sadang station-B1 were selected and calculated the estimated points and ran evaluation experiment using survey positioning error, which is distance between real position and the estimated position. The result shows that Incheon international airport's average and standard deviation was separately 17.81m, 17.79m and Sadang station's average and standard deviation was separately 22.64m, 23.74m. In Sadang station's case, the areas near the exit has low performance of surveying position due to fewer visible AP points than other areas. As total datas were examined except those position, it was verified that the user's location was mapping close position in surveying positioning by using constructed DB. It means that constructed DB contains correct Wi-Fi AP locations and radio wave patterns in object region, so it is considered that the indoor spatial information service based on constructed DB would be available.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.887-892
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• 2019

Many researchers have developed a series of vision-based technologies to monitor construction sites automatically. To achieve high performance of vision-based technologies, it is essential to build a large amount and high quality of training image database (DB). To do that, researchers usually visit construction sites, install cameras at the jobsites, and collect images for training DB. However, such human and site-dependent approach requires a huge amount of time and costs, and it would be difficult to represent a range of characteristics of different construction sites and resources. To address these problems, this paper proposes a framework that automatically constructs a training image DB using web crawling techniques. For the validation, the authors conducted two different experiments with the automatically generated DB: construction work type classification and equipment classification. The results showed that the method could successfully build the training image DB for the two classification problems, and the findings of this study can be used to reduce the time and efforts for developing a vision-based technology on construction sites.

• Journal of the Korean Geographical Society
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• v.40 no.2 s.107
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• pp.153-171
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• 2005

The newly adopted Korea Geodetic Datum (a.k.a. KGD2002) calls for massive reengineering work on geospatial dataset. The main focus of our study is placed on the strategy and system implementations of the required data reengineering with a keen attention to integrated approaches to interoperability, standardization, and database utilization. Our reengineering strategy includes file-to-file, file-to-DB, DB-to-file, and DB-to-DB conversion for the coordinate transformation of KGD2002. In addition to the map formats of existing standards such as DXF and Shapefile, the newly recommended standards such as GML and SVG are also accommodated in our reengineering environment. These four types of standard format may be imported into and exported from spatial database via KGD2002 transformation component. The DB-to-DB conversion, in particular, includes not only intra-database conversion but also inter-database conversion between SDE/Oracle and Oracle Spatial. All these implementations were carried out in multiple computing environments: desktop and the Web. The feasibility test of our system shows that the coordinate differences between Bessel and GRS80 ellipsoid agree with the criteria presented in the existing researches.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.198-208
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• 2021

ArangoDB is a NoSQL database system that has been popularly utilized in many applications for storing large amounts of data. In order to apply a new NoSQL database system such as ArangoDB, to real work environments we need a benchmarking system that can evaluate its performance. In this paper, we design and implement a ArangoDB based benchmarking system that measures a kernel level performance well as an application level performance. We partially modify YCSB to measure the performance of a NoSQL database system in the cluster environment. We also define three real-world workload types by analyzing the existing materials. We prove the feasibility of the proposed system through the benchmarking of three workload types. We derive available workloads in ArangoDB and show that performance at the kernel layer as well as the application layer can be visualized through benchmarking of three workload types. It is expected that applicability and risk reviews will be possible through benchmarking of this system in environments that need to transfer data from the existing database engine to ArangoDB.

• KIEAE Journal
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• v.16 no.6
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• pp.151-157
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• 2016

Purpose: The purpose of this study is to develop and apply an environmental impact assessment program for apartment building elements, based on the building materials of the LCI DB, which can link the LCA results of building materials and buildings. Method: For this purpose, a framework for building elements was established, and several building material combinations were developed. In addition, the LCA method for quantifying environmental load emissions from the building materials of each site was applied to establish an environmental impact database of the building materials of the LCI DB. Result: An environmental impact assessment program, based on a Microsoft Excel worksheet, was developed for apartment building elements. This program can link the environmental impact assessment of building materials and building units. To validate the program evaluation results that were obtained in this study, a comparative analysis was carried out using the results of existing evaluation methods. The error rate was estimated to be 5% for environmental impact assessment using existing evaluation methods.

• Review of KIISC
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• v.18 no.2
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• pp.76-86
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• 2008

인터넷을 통한 공공 및 민간 부분 서비스 제공이 활성화됨에 따라 이들 서비스를 제공받기 위해 사용자들은 자신의 개인정보를 서비스 제공자에게 제공하게 되고, 서비스 제공자들은 가입자들의 개인정보를 관리하기 위해 일반적으로 데이터베이스를 이용하고 있다. 최근 개인정보에 대한 중요도와 필요성이 증가함에 따라 정보보호 제품에 대해 일반 보안기능 및 신뢰성 평가뿐만 아니라 개인정보 소유자의 프라이버시가 보장되는지를 평가할 수 있는 평가기준 마련 필요성이 제기되고 있다. 본 논문에서는 OECD, 미국 FTC, 유럽연합 등 정보보호 선진국에서 제정한 프라이버시 보호원칙과 기존 DBMS 보안 요구사항을 함께 반영한 개인정보 DB 관리기술에 대한 보안 요구사항을 개발하였다. 개발된 보안 요구사항은 TTA 개인정보 생명주기 관리모델(안)의 생명주기 단계를 기준으로 각 생명주기 단계에서 수행되는 기능 특성에 따라DBMS 보안측면과 프라이버시 보호 측면을 함께 고려하여 작성되었다.

• Digital Contents
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• no.11 s.138
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• pp.104-106
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• 2004

디지털콘텐츠산업은 21세기 국가경쟁력을 좌우하는 10대 차세대 성장 동력의 하나이며, 게임산업은 이와 같은 디지털콘텐츠 산업에 있어 가장 경쟁력 있는 분야로 인식되고 있다. 문화관광부가 발간한‘2004 대한민국 게임백서’의 통계자료에 따르면, 2003년 국내 게임시장은 소비자 매출을 기준으로 3조9,000억원 규모로 전년대비 15.8%의 성장을 보였으며, 2006년에는 5조7,000억원 규모의 시장을 형성할 것 으로 전망되고 있다. 특히 온라인게임 시장은 2004년 1조원 시장을 돌파할 것으로 예상된다. 또 국내 게임시장은 해외시장에서 5.3%를 차 지하고 있으며, 온라인게임은 세계시장의 31.4%를 점유, 1위를 기록하고 있어 게임산업이 한국 문화산업을 대표하는 비즈니스로서의 가능 성은 더욱 커지고 있다. 게임산업은 게임 플랫폼과 관련 환경에 적합한 새로운 게임의 개발 여부가 게임산업의 성패를 가늠하며, 이와 같이 빠르게 변화하는 게임시장에서 독점적 우위를 고수하기 위해서는 게임산업의 환경 전반에 걸친 다양한 정보의 수집,제공이 절실하게 필요 하다. 이에 11월의 DB 서비스 평가는 게임산업 전반에 걸친 다양한 정보를 데이터베이스로 구축해 서비스하고 있는 한국게임산업개발원의 ‘게임종합정보시스템(www.gitiss.org)’을 평가해 보고자 한다.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.99-106
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• 2019

Technology that cannot be excluded from 4th industry is self-driving sector. The self-driving sector can be seen as a key set of technologies in the fourth industry, especially in the DB sector is getting more and more popular as a business. The DB, which was previously produced and managed in two dimensions, is now evolving into three dimensions. Among the data obtained by Mobile Mapping System () to produce the HD MAP necessary for self-driving, Point Cloud, which is LiDAR data, is used as a DB because it contains accurate location information. However, at present, it is not widely used as a base data for 3D modeling in addition to HD MAP production. In this study, MMS Point Cloud was used to extract facilities around the road and to overlay the location to expand the usability of Point Cloud. Building utility poles and communication poles DB from Point Cloud and comparing road name address base and location, it is believed that the accuracy of the location of the facility DB extracted from Point Cloud is also higher than the basic road name address of the road, It is necessary to study the expansion of the facility field sufficiently.