• Imaging Science in Dentistry
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• v.49 no.4
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• pp.257-263
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• 2019

Purpose: This study was performed to evaluate the dimensional accuracy of digital dental models constructed from cone-beam computed tomographic (CBCT) scans of polyvinyl siloxane (PVS) impressions and cast scan models. Materials and Methods: A pair of PVS impressions was obtained from 20 subjects and scanned using CBCT (resolution, 0.1 mm). A cast scan model was constructed by scanning the gypsum model using a model scanner. After reconstruction of the digital models, the mesio-distal width of each tooth, inter-canine width, and inter-molar width were measured, and the Bolton ratios were calculated and compared. The 2 models were superimposed and the difference between the models was measured using 3-dimensional analysis. Results: The range of mean error between the cast scan model and the CBCT scan model was -0.15 mm to 0.13 mm in the mesio-distal width of the teeth and 0.03 mm to 0.42 mm in the width analysis. The differences in the Bolton ratios between the cast scan models and CBCT scan models were 0.87 (anterior ratio) and 0.72 (overall ratio), with no significant difference (P>0.05). The mean maxillary and mandibular difference when the cast scan model and the CBCT scan model were superimposed was 53 ㎛. Conclusion: There was no statistically significant difference in most of the measurements. The maximum tooth size difference was 0.15mm, and the average difference in model overlap was 53 ㎛. Digital models produced by scanning impressions at a high resolution using CBCT can be used in clinical practice.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.2
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• pp.68-75
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• 2014

Objectives: This study was performed to analyze the cumulative survival rate of Osstem implants (Osstem Implant Co., Ltd.) over a seven-year period. Materials and Methods: A total of 105 patients who had 467 Osstem implants that were placed at the Section of Dentistry, Seoul National University Bundang Hospital (Seongnam, Korea) from June 2003 through December 2005 were analyzed. The life table method and a cross-tubulation analysis, log rank test were used to evaluate the survival curve and the influence that the prognostic factors. The prognostic factors, i.e., age and gender of patients, diameter and length, type of implants, bone graft history and loading time were determined with a Cox proportional hazard model based on logistic regression analysis. Results: The seven-year cumulative survival rate of Osstem implants was 95.37%. The Cox proportional hazard model revealed that the following factors had a significant influence on survival rate; increased diameter, reduced prosthetic loading period and performance of bone grafting. Conclusion: The osstem implants showed satisfactory results over the seven-year study period.

• The Journal of Bigdata
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• v.1 no.2
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• pp.65-78
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• 2016

In the rapid change of business environment, it is crucial that several companies with core competence cooperate together in order to deliver competitive products to the market faster. Thus a lot of companies are participating in supply chains and SCM (Supply Chain Management) become more important. To efficiently manage supply chains, the analysis of data from SCM systems is required. In this paper, we explain how to analyze SCM related data with process mining techniques. After discussing the data requirement for process mining, several process mining techniques for the data analysis are explained. To show the applicability of the techniques, we have performed a case study with a company in South Korea. The case study shows that process mining is useful tool to analyze SCM data. On specifically, an overall process, several performance measures, and social networks can be easily discovered and analyzed with the techniques.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.184-184
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• 2003

• Korean Journal of Construction Engineering and Management
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• v.1 no.3 s.3
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• pp.116-123
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• 2000

SOC projects entail inherently large-scale works, and need much capital and time. Because of these features, the design activities in SOC projects are performed through a complicated process involving many organizations. A great deal of information is generated and vanished during the process, and the communication among the related organizations plays a very important role in successful fulfillment of SOC projects. But, because the method of information communication has not yet systematically established, there are many difficulties in sharing information. This study aims at establishing the design interface management model which enables the participants to effectively share the information during the design phase. The contents of the study include (1) Restructuring performance organization, (2) A decision making method in collaborative design through partnering with experts, (3) A method to develop Open Design Information Integrated model using Standardization(ODIIS).

• The Korean Journal of Nuclear Medicine
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• v.23 no.1
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• pp.49-54
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• 1989

Many previously described nuclear medicine procedures to assess glomerular filtration rate (GFR) required numerous blood samples obtained over a period of several hours to determine plasma concentrations of the injected radiopharmaceuticals. And other indirect methods of determining renal clearance have some problems due to individual variations in volume of distribution of the radionuclides used. Rescently reported Jackson's method have the great advantages that is a direct measurement method requiring less than 40 min of imaging time and single blood sampling. And it correctly accounts for individual variations in volume of distribution of the radiopharmaceuticals and can be done with routine renal scintrgraphy. We measured $^{99m}Tc-DTPA$ renal clearance with Jackson's method during the routine $^{99m}Tc-DTPA$ renal scintigraphy in 63 patients admitted to department of internal medicine in SNUH. In 23 cases among 63 patients creatinine clearence was accounted simultaneously. The range of $Cl_{DPDA}$ was from 19.9 ml/min to 170 ml/min and the correlation of $Cl_{DPDA}$ and creatinine clearance was discribed by Y=16.2570+0.7852 X($X=Cl_{DTPA}$ Y=creatinine clearance). And the correlation coefficient r was 0.88. We concluded that $^{99m}Tc-DTPA$ renal clearance measurement with Jackson's method was clinically useful to account GFR that can be done with routine $^{99m}Tc-DTPA$ renal scintigraphy simultaneously.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.313-318
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• 2014

The remote monitoring system of water salinity was assessed in Wando reclaimed land lake during a farming season in 2009. Increasing of water salinity in this lake used to bring about salt damage on rice plant occasionally. At the early stage of the rice growing period, rice growth was not damaged due to enough rainfall with more than 120 mm from the mid-May to the first ten days of June. Data collection using on-site water salinity measuring sensors every 2 hours and real-time transmission in system were carried out for the experiment. We compared the transmitted values from the sensor system with water sample values collected and analyzed by a local technical office. Salt concentrations measured by sensor in real-time monitoring system were available data. The regression equation between rainfall and water salinity was presented as (water salinity after rainfall) = $0.621{\times}$(water salinity before rainfall)${\times}exp(-0.0139{\times}rainfall)$, ($r^2=0.579$, p<0.01). It is suggested that the system is useful for stable farming in the area where farmer use water in reclaimed lakes as an irrigation source.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.1-10
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• 2011

Recently harbor remodeling projects are seriously considered to enhance the loading and unloading capability of old container terminals and to make decrepit ports as eco-friendly harbor and waterfront spaces in many countries. In such a case, quantitative and qualitative evaluations on concrete harbor facilities are mandatory to determine the current structural integrity condition of aged materials. Once the remodeling project is determined to be carried out, the reusability of individual structural members and facilities including caissons, cell-blocks, and tetra-pods need to be decided based on the simple and economic visual inspection and/or nondestructive testing. In this study, the systematic quantitative evaluation procedure for determining the structural integrity condition and the reusability is studied based the nondestructive testing and evaluation methods. Conventional methods including Schmidt hammer test and ultrasonicpulse velocity methods and elastic wave based methods including impact echo test and surface wave test are applied to the old harbor facilities in five different sites. The compressive tests are also carried out to determine the elastic modulus and compressive strength of concrete materials.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.11-17
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• 2011

A major source of durability problems in concrete structures is the corrosion of steel by the damage of passivity layer around steel bars. As chloride ion penetration is major cause of the destruction of passivity layer, evaluation of depth and concentration profile of chloride ion is the essential factor for the service-life estimation of concrete structure. To estimate chloride ion penetration characteristics, this paper on the basis of in-situ experimental data investigated the depth and concentration profile of chloride ion penetration. The core specimens are obtained at air-zone, splash zone, and tidal zone in Wando, Masan, Incheon, Gwangyang, and donghae harbors. Colorimentric method measured the chloride ion penetration depth and ASTM C 114 evaluated the concentration profile of chloride ion. Based on experimental data, the influence of harbor location and exposure condition on chloride ion penetration is evaluated.

• Journal of Korean Medical classics
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• v.25 no.2
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• pp.107-123
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• 2012

Objective : Kyungakjeonsuh(景岳全書) is a general medical book written by Jang, Gaebin(張介賓). In this book, Maekshinjang(脈神章) written about Maek, has three parts: (1)Naegyung maekui(內經脈義); (2)Tongiljamaekui(通一子脈義); (3)various views of Maek according to different schools. Among these three parts, Tongiljamaekui is Jang Gaebin's view on Maek, which is also called Jungmaek 16parts(正脈16部), a summary of the existing theory of Maek. Method : The contents of this paper are Chesangshi(體狀詩), literally means Body and Condition and Joobyingshi(主病詩), literally means Major Ailment of Binhohmaekhak(瀕湖脈學), and Jungmaek 16parts of Maekshinjang, and the result of examination through comparing them. Result : The purpose of this paper is to indicate the characters of the theories of Maek written in Kyungakjeonsuh through comparing Jungmaek 16 parts and Binhohmaekhak written by Doctor Yi, Shijin(李時珍), which is the basic study of Maek. Conclusion : The major study sectors of Kyungakjeonsuh are (1) the summary of the existing Maeksang as 16 Maeks, (2) the new definition of Huh Maek(虛脈) and Shil Maek(實脈) and (3) the utilization of eight-class-demonstration(8綱辨證) with 6 Maeks (浮, 沈, 遲, 數, 虛, 實) as a general principle.