• Spatial Information Research
• /
• v.19 no.3
• /
• pp.23-31
• /
• 2011

As demands of intelligent urban geospatial information services are increasing in u-Cities, development and use of service standards for the cities are required to make the services interoperable. Conformance tests can be conducted for the standards to implement the services more interoperably and consistently. To improve the interoperability between services, it is necessary to build an evaluation model for services in a perspective of conformance tests. In the context, this study reviews the related references and establishes a conceptual model of the conformance tests for the services and provides an application of the model to a monitoring service for flowing water quantity to prove its usefulness.

• Aerospace Engineering and Technology
• /
• v.6 no.1
• /
• pp.222-229
• /
• 2007

Environmental tests should be carried out to show that design performance is in an operational condition in an actual operational environment to assure maintainability and reliability. Aero-products electromagnetic compatibility tests are performed mainly for the individual parts and Specifications MIL-STD-461E and RTCA DO-160E are developed for the military and commercial parts tests respectively. The MIL-STD-461E which is a military environmental test standard is targeting all munitions and that user can apply by selecting applicable requirements from this specification. On the other hand, requirements are applied exclusively for the Avionics Equipments in commercial test standard.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.1078-1083
• /
• 2009

HEC-HMS(Hydrologic Modeling System)은 강우-유출 모의를 위한 차세대 소프트웨어이며 HEC-1에 포함되어 있는 단위도 및 수문학적 홍수추적 이외에도 격자형 강우자료(레이더 데이터)를 이용하여 적용할 수있는 유사분포 유출변화와 장기 연속모의에 적용할 수 있는 간단한 수분감소 등을 추가적으로 포함하고 있다. 또한 GUI(Graphical User Interface)환경, 통합 수문분석 성분, 자료 저장 및 관리 능력, 그래�d 처리 및리포트 출력기능으로 구성되어 있으며 여러 가지 프로그램 언어(C, C++, Fortran)를 이용하여 개발되었다. 본 연구에서는 낙동강 수계의 금호강에 위치한 동촌 지점을 유출구로 선정하고 5개의 소유역과 두 개의 하도로 구성하여 유출모의를 실시하였으며 수문자료 선정은 2007년$^{\sim}$2008년에 발생한 홍수사상과 유량조사 사업단에서 개발한 수위-유량관계곡선식을 활용하였다. 또한, HEC-GeoHMS 모형을 GIS와 연계하여 지형인자를 추출하고 추출된 지형인자를 이용하여 매개변수를 산정하였다. HEC-HMS 모형의 계산 조건에서 손실 우량은 SCS CN, 유출변환은 Clark 단위도법을 적용하였다. 또한 관측치와 계산치의 적합도 검증은 평균제곱 근오차(root mean squar error; RMSE)와 모형 효율성 계수(model efficiency; ME)를 산정하여 분석하였다

• The Journal of the Korea Contents Association
• /
• v.10 no.10
• /
• pp.9-18
• /
• 2010

As digital contents become vast in quantity, it takes long time for users to search the digital contents they want, which is a problem that has arisen. Therefore, it is required to have the technology that analyzes vast digital contents and extracts the appropriate contents for users in order to provide them with contents they want. For a fast searching of digital contents suitable for users, it is necessary to have the technology of filtering for digital contents. In this paper, we propose a method of filtering digital contents suitable for individual users. The method suggested in this paper is to analyze case-based information in digital contents and provide the digital contents suitable for individual users. The case for using digital contents is used for analysis of users' preference. Various simulations were conducted to confirm the effectiveness of the proposed method.

• The Korean Journal of Applied Statistics
• /
• v.6 no.2
• /
• pp.421-433
• /
• 1993

Few ovservation can influence in model building procedure and can dominate the least squares fit of a selected model. An observation, however, may not have the same impact on all aspects of regression analysis. We introduce a statistic which measures the impact of individual cases on the overall goodness-of-fit statistics. We also propose an influence measure for variable selection problem. The property of uncorrelatedness between fitted values and residuals has been used to develop the influence measure. The performance of the measures are used to develop the influence measure. The performance of the measures are compared with other widely used influence measures by the analysis of real data.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.12 no.2
• /
• pp.111-119
• /
• 2009

The purpose of this study is to decide the suitability of the land use on eco-city by analysing ecological elements using GIS. Selected ecological elements for suitability analysis were altitude, slope, watershed, biotope, soil productivity, visual sensitivity, vegetation, and green connection. The category of each element was classified into 5 grades, and was given weight according to each element. The maximum value of each element was extracted from overlay analysis process. The result of analysis was classified into 5 grade finally. As a result, land use was proposed to be development, conservation, and preservation area.

• Journal of Korea Water Resources Association
• /
• v.44 no.8
• /
• pp.639-652
• /
• 2011

In this study, the suitability of drought indices was analyzed using the quantified drought records from official reports, newspapers and drought indices estimated using precipitation and air temperature data of 69 weather stations from 1973 to 2009. Test statistics of the suitability of meteorological drought indices were evaluated using the ROC analysis. Results demonstrated that PN shows the best relationships with drought records. SPI3 and Deciles Distribution Ratio also show good relationships with drought records and their variability according to the administrative divisions is relatively small. Results of the analysis of the spatial and temporal variability of drought and the accuracy of the drought indices can be used to evaluate the accuracy of drought indices in drought monitoring and prediction, and to select the best index in drought management.

• Journal of Korean Society of Transportation
• /
• v.25 no.3
• /
• pp.123-135
• /
• 2007

The objective of this study is to analyze the relationship between traffic accidents occurring at trumpet interchange ramps according to accident type as well as the relevant factors that led to the traffic accidents, such as geometric design elements and traffic volumes. In the process of analysis of the distribution of traffic accidents, negative binomial distribution was selected as the most appropriate model. Negative binomial regression models were developed for total trumpet interchange ramps, direct ramps, loop ramps and semi-direct ramps based on the negative binomial distribution. Based upon several statistical diagnostics of the difference between observed accidents and predicted accidents with four previously developed models, the fit proved to be reasonable. Understanding of statistically significant variables in the developed model will enable designers to increase efficiency in terms of road operations and the development of traffic accident prevention policies in accordance with road design features.

• Journal of the Korea Society of Computer and Information
• /
• v.20 no.4
• /
• pp.119-130
• /
• 2015

This study empirically analyzed at domestic manufacturing and service firms to find any moderating effects of enterprise management strategies and information-oriented development strategies between enterprise characteristic factors and IT adoption performance. Task characteristics were analyzed based on information provision extent, system quality and perceived effects while environmental characteristics based on competition extent, external pressure, environmental uncertainty, etc. As a result it was found that strategic suitability factors had a moderating effect between adoption performance and task characteristic variables such as system quality and perceived effect, environmental characteristics such as competition level, external pressure and environmental uncertainty. However, strategy suitability was found not to have any moderating role between task characteristic information provision extent and adoption performance. These findings indicate that enterprises need to plan and implement corporate management strategies and information-oriented development strategies in close coordination for new IT adoption and spread.

• Communications for Statistical Applications and Methods
• /
• v.16 no.4
• /
• pp.605-614
• /
• 2009

TGARCH models characterized by asymmetric volatilities have been useful for analyzing various time series in financial econometrics. We are concerned with persistent volatility in the TGARCH context. Park et al. (2009) introduced I-TGARCH process exhibiting a certain persistency in volatility. This article applies I-TGARCH model to various financial time series in Korea and it is obtained that I-TGARCH provides a better fit than competing models.