• Journal of Periodontal and Implant Science
• /
• v.45 no.1
• /
• pp.23-29
• /
• 2015

Purpose: This study was conducted to compare the cumulative survival rates (CSRs) and the incidence of postloading complications (PLCs) between a bone-level internal connection system (ICS-BL) and an external connection system (ECS). Methods: The medical records of patients treated with either a ICS-BL or ECS between 2007 and 2010 at Asan Medical Center were reviewed. PLCs were divided into two categories: biological and technical. Biological complications included >4 mm of probing pocket depth, thread exposure in radiographs, and soft tissue complications, whereas technical complications included chipping of the veneering material, fracture of the implant, fracture of the crown, loosening or fracture of the abutment or screw, loss of retention, and loss of access hole filling material. CSRs were determined by a life-table analysis and compared using the log-rank chi-square test. The incidence of PLC was compared with the Pearson chi-squared test. Results: A total of 2,651 implants in 1,074 patients (1,167 ICS-BLs in 551 patients and 1,484 ECSs in 523 patients) were analyzed. The average observation periods were 3.4 years for the ICS-BLs and 3.1 years for the ECSs. The six-year CSR of all implants was 96.1% (94.9% for the ICS-BLs and 97.1% for the ECSs, P=0.619). Soft tissue complications were more frequent with the ECSs (P=0.005) and loosening or fracture of the abutment or screw occurred more frequently with the ICS-BLs (P<0.001). Conclusions: Within the limitations of this study, the ICS-BL was more prone to technical complications while the ECS was more vulnerable to biological complications.

• IE interfaces
• /
• v.23 no.4
• /
• pp.311-318
• /
• 2010

In the daily multi-reservoir operating problem, monthly storage targets can be used as principal operational guidelines. In this study, we tested the use of a simple back-propagation Artificial Neural Network (ANN) model to derive monthly storage guideline for daily Coordinated Multi-reservoir Operating Model (CoMOM) of the Han-River basin. This approach is based on the belief that the optimum solution of the daily CoMOM has a good performance, and the ANN model trained with the results of daily CoMOM would produce effective monthly operating guidelines. The optimum results of daily CoMOM is used as the training set for the back-propagation ANN model, which is designed to derive monthly reservoir storage targets in the basin. For the input patterns of the ANN model, we adopted the ratios of initial storage of each dam to the storage of Paldang dam, ratios of monthly expected inflow of each dam to the total inflow of the whole basin, ratios of monthly demand at each dam to the total demand of the whole basin, ratio of total storage of the whole basin to the active storage of Paldang dam, and the ratio of total inflow of the whole basin to the active storage of the whole basin. And the output pattern of ANN model is the optimal final storages that are generated by the daily CoMOM. Then, we analyzed the performance of the ANN model by using a real-time simulation procedure for the multi-reservoir system of the Han-river basin, assuming that historical inflows from October 1st, 2004 to June 30th, 2007 (except July, August, September) were occurred. The simulation results showed that by utilizing the monthly storage target provided by the ANN model, we could reduce the spillages, increase hydropower generation, and secure more water at the end of the planning horizon compared to the historical records.

• The Journal of Fisheries Business Administration
• /
• v.41 no.3
• /
• pp.103-127
• /
• 2010

The FAO reports that IUU fishing activities have widespread economic, social, and management consequences, including depriving legitimate fishers of harvest opportunities. It affects all fisheries from small scale to industrial. It also affects the ability of governments to support sustainable livelihoods for fishers and, more broadly, to achieve food security. The complexity of IUU requires various measures to combat IUU fishing such as adoption of IUU vessel lists; stronger port State controls; improved monitoring, control and surveillance (MCS); implementation of market-related measures to help ensure compliance; and capacity-building assistance. Trade and market measures reduce opportunities for IUU fishing activities by precluding or impeding access to markets for IUU product in a manner consistent with international law. ICCAT, CCAMLR, and IATTC, have put in place trade tracking programs or catch documentation schemes, and WCPFC is considering such a program. Vessel lists assist enforcement authorities in determining which vessels are or are not authorized to be fishing or conducting fishing support activities in specified areas. A number of RFMOs maintain records of IUU vessels: CCAMLR, IATTC, ICCAT, NAFO, NASCO, NPAFC, WCPFC. Section 608 of the US MSRA calling on the Secretary of Commerce, in consultation with the Secretary of State, and in cooperation with relevant regional fishery management councils and any relevant advisory committees, to take actions to improve the effectiveness of international fishery management organizations in conserving and managing stocks under their jurisdiction. EU IUU Regulation entered into force on 1 January 2010, was intended to regulate the highly complex multi-channel fisheries supply system of the European Community (EC) in an effort to improve global fisheries sustainability.

• Journal of Digital Convergence
• /
• v.11 no.10
• /
• pp.387-394
• /
• 2013

Data mining is the process of discovering hidden, non-trivial patterns in large amounts of data records in order to be used very effectively for analysis and forecasting. Because hundreds of variables give rise to a high level of redundancy and dimensionality with time complexity, they are more likely to have spurious relationships, and even the weakest relationships will be highly significant by any statistical test. Hence cluster analysis is a main task of data mining and is the task of grouping a set of objects in such a way that objects in the same group are more similar to each other than to those in other groups. In this paper system implementation is of great significance, which defines a new definition based on information-theoretic entropy and analyse the analogue behaviors of objects at hand so as to address the measurement of uncertainties in the classification of categorical data. The sources were taken from a survey aimed to identify of job guidance from students in high school pyeongtaek. we show how variable precision information-entropy based rough set can be used to group student in each section. It is proved that the proposed method has the more exact classification than the conventional in attributes more than 10 and that is more effective in job guidance for students.

• Water for future
• /
• v.27 no.3
• /
• pp.45-54
• /
• 1994

Basic theory of fractal dimension is introduced and performed for the generated time series using the water balance model. The water balance equation over a large area is analyzed at seasonal time scales. In the generation and modification of mesoscale circulation local recycling of precipitation and dynamic effects of soil moisture are explicitly included. Time delay is incorporated in the analysis. Depending on the parameter values, the system showed different senarios in the evolution such as fixed point, limit cycle, and chaotic types of behavior. The stochastic behavior of the generated time series is due to deterministic chaos which arises from a nonlinear dynamic system with a limited number of equations whose trajectories are highly sensitive to initial conditions. The presence of noise arose from the characterization of the incoming precipitation, destroys the organized structure of the attractor. The existence of the attractor although noise is present is very important to the short-term prediction of the evolution. The implications of this nonlinear dynamics are important for the interpretation and modeling of hydrologic records and phenomena.

• Journal of the Korean Society for Library and Information Science
• /
• v.41 no.3
• /
• pp.25-53
• /
• 2007

The purpose of this study is to analyze the characteristics of OPAC displays and search interfaces for children. The OPACS of Cheongju Miracle Library, Nowon Children's Library in Seoul. Los Angeles Public Library in the U.S.A. and HelMet Library System in Finland are examined on the basis of 'OPAC Display Guidelines(Draft)' published by IFLA and Nielsen's 'User Interface Design Heuristics'. Discussed are such topics as the features of basic and detailed search screens. the brief display of search results. the arrangement and full display of bibliographic records, and the displays for zero-results and large retrieval sets. The OPAC displays of Cheongju Miracle Library and Nowon Children' Library are not particularly designed to serve children which are their primary users. The OPAC displays for children of LAPL and HelMet Library System are rather simplified and customized to represent specifically the needs and information seeking behavior of children.

• Journal of Preventive Medicine and Public Health
• /
• v.40 no.4
• /
• pp.329-335
• /
• 2007

Objectives : To identify the effects of supplemental private health insurance on health care utilization and expenditure under the mandatory National Health Insurance(NHI) system in Korea. Methods : The data were collected by the National Cancer Center in Korea. Cancer patients who were newly diagnosed with stomach (ICD code, C16), lung(C33-C34), liver (C22), colorectal cancer(C18-C20) or breast(C50) cancer were included as study subjects. Data were gathered using a structured questionnaire from face-to-face interviews, the hospital Order Communication System (OCS) and medical records. Clinical, socio-demographic and private health insurance related factors were also gathered. The differences of health care utilization and expenditure were compared between those who have private health insurance and those who do not using t-test and multivariable regression analysis. Results : Individuals with private health insurance spent larger inpatient costs than those without, but no differences were found in utilization in other service such as hospital admissions, hospital days and physician visits. Conclusions : We found that private health insurance exerts a significant effect on the health care expenditure in inpatient service. These study results can provide a rational basis to plan a national health policy regarding private health insurance. Further studies are needed to investigate the impacts of private health insurance on cancer patients' outcomes and survival rates.

• Journal of the Korean Home Economics Association
• /
• v.41 no.7
• /
• pp.59-71
• /
• 2003

Koreans were started moving to Yunhaju in Russia for escaping from tyrannical rule and famine in 1860's in Korea. Social and political situation of Russia were made it very hard to get to know about Korean's life there so far. But it was known that Korean Diaspora has been kept traditional way of living in without contacts between Korea for 140 years. This study examined the dwellings of Korean Diaspora in Yunhaju through reviewing related documents and records firstly and had a time to visit places which Koreans lived since 1860's for example Posyet(equation omitted), Suifen(equation omitted), Ussuriisk(equation omitted), Vladivostok(equation omitted), Partizansk(equation omitted) and took interviews with Koreans who lived there pre 1930's. Results of research were as following : 1) A first place to settle down for Koreans in Yunhaju was Posye(equation omitted) and scattered as time goes by far away from there. 2) Koreans were helping each other for living and they had their own self managing organizations in village there. 3) The villages which was made in Yunhaju by Koreans in the beginning were similar to traditional ones in Korea. 4) It was verified that dwellings which was built by Koreans in Yunhaju were similar to ones in north area in Korea. At that time lots of Korean Diaspora came from north part and they kept their own traditional way of building houses there for a long time. 5) Korean Diaspora have been kept traditional heating system ‘Ondol’ in their various types of houses until now in Yunhaju. Moreover, it is known that Russians prefer to set ‘Ondol’ in their houses recently as a very special and expensive heating system. This study would be a very good opportunity to standing out Korean history of housing in Yunhaju as well as evaluating their identification as Koreans. For this, it is needed to take more deep research in specific areas which could see more various types of housing and could compare ones between two countries.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.1
• /
• pp.93-100
• /
• 2008

A multi-nesting grid storm surge model, Korea Ocean Research and Development Institute-Storm surge model, was calibrated to simulate storm surges. To check the performance of this storm surge model, a series of numerical experiments were explored including tidal calibration, the influence of the open boundary condition, the grid resolutions, and typhoon paths on the surge heights using the typhoon Maemi, which caused a severe coastal disasters in Sep. 2003. In this study the meteorological input data such as atmospheric pressure and wind fields were calculated using CE wind model. Total 11 tidal gauge station records with 1-minute interval data were compared with the model results and the storm surge heights were successfully simulated. The numerical experiments emphasized the importance of meteorological input and fine-mesh grid systems on the precise storm surge prediction. This storm surge model could be used as an operational storm surge prediction system after more intensive verification.

• Journal of Information Management
• /
• v.40 no.3
• /
• pp.151-176
• /
• 2009

The purpose of this study is to propose effective management plan for official seal guaranteeing authenticity of archival records. For this, this paper attempts to investigate current management conditions of central governments and National Archives. First, disclosure of information on official seal register in central government was requested. In addition, surveys and interviews with person in charge were carried out. Additionally, official seal lists of National Archives were analyzed and the person in charge was interviewed. Based on these, this paper proposed management plans of official seal such as a periodic inspection of management conditions, training programs for the person in charge, selective acquisition, reporting of the current state, improvement of law system, improvement of document formats, and establishment of an electronic seal management system, etc.