• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2002.09a
• /
• pp.28-34
• /
• 2002

The b-value in the magnitude-frequency relationship logN(m) = $\alpha$ - bmwhere N(m) is the number of earthquakes exceeding magnitude m, is important seismicity parameter In hazard analysis. Estimation of the b-value for earthquake data observed on KSRS array network is done employing the maximum likelihood technique. Assuming the whole Korea Peninsula as a single seismic source area, the b-value is computed at 0.9. The estimation for KMA earthquake data is also similar to that. Since estimate is a function of minimum magnitude, we can inspect the completeness of earthquake catalog in the fitting process of b-value. KSRS and KMA data lists are probably incomplete for magnitudes less than 2.0 and 3.0, respectively. Examples from probabilistic seismic hazard assessment calculated for a range of b-value show that the small change of b-value has seriously effect on the prediction of ground motion.

• Korean Management Science Review
• /
• v.18 no.2
• /
• pp.73-85
• /
• 2001

Recently increasing amount of efforts has been devoted to the improvement of logistics in the marine products industry. Yet, few studios have been conducted on the development of site selection models of marine products centers. This paper Proposes a systematic assessment model for the decision making, which is composed of a set of evaluation criteria and an appropriate evaluation method. In choosing criteria we consider completeness and comprehensiveness to reach a right solution. For more flexibility of the model in the future, this study proposes two sets of criteria according to the size of planned centers. The Analytic Hierarchy Process (AHP) is adopted in this study, since the criteria incorporate both subjective factors and objective factors and the AHP is known effective in the situation. This study then illustrates the model application with plausible alternatives. Finally, a dependency problem in the decision criteria is discussed and the Analytic Network Process (ANP) is recommended, in the context, as e solution method.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.21 no.2
• /
• pp.198-204
• /
• 1999

The treatment of cleft lip and palate patients requires multidisciplinary coorperation, and the involved clinicians rely on the completeness and accuracy of the patient's medical records in developing comprehensive treatment plans. There are so many classifications in cleft lip and palate but each classification has advantages and disadvantages. Furthermore there are few classification or assessment in secondary cleft lip and palate deformities. A modification of Kenahan's Y classification in primary cleft lip and palate and new classification in secondary cleft lip and palate deformities are proposed as a simple and reproducible method. These reproducible classification may be used to facilitate not only storing and analyzing of medical informations in computer but also the planning of secondary repairs

• Journal of Advanced Navigation Technology
• /
• v.27 no.1
• /
• pp.133-138
• /
• 2023

As a side effect of recent rapid climate change and global warming, the frequency and scale of flood disasters are increasing worldwide. In Korea, the water level of the Han River is a major management target for preventing flood disasters in Seoul, the capital of Korea. In this paper, to improve the water level prediction of the Han River based on machine learning, we perform a comprehensive assessment of the quality of related dataset and propose data preprocessing methods to improve it. Specifically, we improve the dataset in terms of completeness, validity, and accuracy through missing value processing and cross-correlation analysis. In addition, we conduct a performance evaluation using random forest and LightGBM to analyze the effect of the proposed data improvement method on the water level prediction performance of the Han River.

• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.6
• /
• pp.348-355
• /
• 2017

Human activities have resulted in soil pollution problems to us. Human and ecological risk assessment have been suggested as an efficient environmental management strategy for protecting human and ecosystems from soil pollution. However, Korean environmental policy is currently focused on human protection, and fundamental researches for ecology protection are required for institutional frameworks. In this study, we developed a schematic frame of Korean soil ecological risk assessment, and suggested the basic information for its application. This study suggested a soil ecological risk assessment scheme consisting of 4 steps for derivation of Predicted-No-Effect-Concentration (PNEC): 1) ecotoxicity data collection and reliability determination, 2) data standardization, 3) evaluation of data completeness for PNEC calculation, and 4) determination of ecological-risk. The reliability determination of ecotoxicity data was performed using Reliability Index (RI), and the classification of domestic species, acute/chronic, toxicity endpoint, and soil properties was used for data cataloging. The PNEC calculation methodology was determined as low-reliability, middle-reliability, and high-reliability according to their quantitative and qualitative levels of ecotoxicity data. This study would be the introductory plan research for establishment of Korean soil ecological risk assessment, and it can be a fundamental framework to further develop guidelines of Korean environmental regulation.

• Journal of Environmental Health Sciences
• /
• v.37 no.1
• /
• pp.1-11
• /
• 2011

Recent advances in Geographic Information Systems and spatial statistical and analytical methods, along with the availability of spatially referenced health and environmental data, have created unique opportunities to investigate spatial associations between environment exposures and health outcomes at multiple spatial scales and resolutions. However, the increased use of spatial data also faces challenges, one of which is to ensure certainty and accuracy of locational data that meets the needs of a study. This article critically reviews the use of spatially referenced data in epidemiologic studies, focusing on the issue of locational uncertainty generated from the process of geocoding health and environmental data. Primarily, major issues involving the use of spatially referenced data are addressed, including completeness and positional accuracy, potential source of bias and exposure misclassification, and implications for epidemiologic studies. The need for critical assessment and caution in designing and conducting spatial epidemiology studies is briefly discussed.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.4
• /
• pp.491-499
• /
• 2000

Objective : In the cerebral aneurysm surgery, the goal is complete circulatory exclusion of the aneurysm without compromise of normal vessels. In an operating room, an operator should confirm the completeness and precision of the surgical result, before closing the wound. Object of this study was to determine which cases require intraoperative angiography. Methods : We reported our experience with 48 intraoperative angiographic studies performed during the surgical treatment of cerebral aneurysm of these 48 cases. There were 5 giant(10.4%), 15 globular(1.5-2.5cm)(31.25%) and 28 saccular(58.3%) aneurysm. We recorded the incidence of unexpected findings, such as residual aneurysms, major vessel occlusions. Using Fischer's exact test, we assessed whether unexpected angiographic findings showed any correlation with aneurysm site, size and clinical findings. Results : In 5 cases(10.4%), we detected unexpected angiographic findings which resulted in clip adjustment. By means of clip adjustment, an operator could restore the flow of two major arterial occlusion(4.2%) and also obliterate three persistent filling aneurysms(6.3%). Globular aneurysm was the only factor to predict unexpected angiographic findings(p<0.05). The subgroup of globular and giant aneurysm has a high risk of occlusion of the parent artery and its branches and/or residual aneurysm. There were two minor complications related to this procedure. Conclusion : Intraoperative assessment makes it possible to recognize and correct the technical defect. Particularly in globular aneurysm, we were able to prevent both the chance for another operation and the risk of postoperative complications.

• International Journal of Computer Science & Network Security
• /
• v.22 no.10
• /
• pp.347-351
• /
• 2022

The article is devoted to the formation of approaches to improving the system of administration of customs payments in modern conditions. It is established that important components of the administration of customs payments are customs expertise, customs value assessment, and control over the declaration of goods to ensure the completeness and timeliness of customs duties payments to the budget. It is found that the practice of customs administration shifts the emphasis of foreign trade regulation to the use of the principles of work implying the use of the latest technologies for the preliminary electronic exchange of information, remote customs clearance of goods without the physical presence of an official, and consistent application of risk management. It is established that an important place in the structure of the state authorities regulating the foreign economic activity is given to the customs service. Furthermore, the existing problems in the implementation of international trade operations necessitate the improvement of approaches to the customs regulation of export-import activities of enterprises.

• Journal of the Korean Society for Library and Information Science
• /
• v.49 no.4
• /
• pp.241-264
• /
• 2015

Bibliometric analysis for research performance evaluation can generate erroneous assessments for various reasons. Application of the same evaluation metric to different domains, for instance, can produce unfair evaluation results, while analysis based on incomplete data can lead to incorrect conclusions. This study examines bibliometric data of library and information science (LIS) research in Korea to investigate whether research performance should be evaluated in a uniform manner in multi-disciplinary fields such as LIS and how data incompleteness can affect the bibliometric assessment outcomes. The initial analysis of our study data, which consisted of 4,350 citations to 1,986 domestic papers published between 2001 and 2010 by 163 LIS faculty members in Korea, showed an anomalous citation pattern caused by data incompleteness, which was addressed via data projection based on past citation trends. The subsequent analysis of augmented study data revealed ample evidence of bibliometric pattern differences across subject areas. In addition to highlighting the need for a subject-specific assessment of research performance, the study demonstrated the importance of rigorous analysis and careful interpretation of bibliometric data by identifying and compensating for deficiencies in the data source, examining per capita as well as overall statistics, and considering various facets of research in order to interpret what the numbers reflect rather than merely taking them at face value as quantitative measures of research performance.

• Journal of Software Assessment and Valuation
• /
• v.16 no.1
• /
• pp.27-36
• /
• 2020

The software development cost appraisal is treated as a part of the program completion appraisal, and the software engineering methodology is applied. In particular, software cost estimation techniques have been actively applied. For more information about the software development costs calculation, we can refer to the "SW cost estimation guide". Although successful appraisal of a number of development costs based on the guide has been processed, but a number of cases requiring discussion of appraisal results have been discovered. In this study, we propose a use case-based size estimation method to maintain the accuracy and consistency of size estimation. As a result of performing performance evaluation of the proposed method in an environment similar to the development cost appraisal case, it was proved that the accuracy was improved over the existing function points method.