• The korean journal of orthodontics
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• v.33 no.6 s.101
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• pp.407-418
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• 2003

The purpose of this study is to analyze dentoalveolar compensation in normal occlusion samples previously classified into 9 skeletal types, and to provide clinically applicable diagnostic criteria for individual malocclusion patients. Cephalometric measurements of the 294 normal occlusion samples previously divided into 9 types were analyzed. The descriptive features of dentoalveolar variables were compared for the 9 types using analysis of variance, followed by post hoc multiple comparisons. In addition, the correlation between skeletal and dentoalveolar variables were analyzed. Discriminant analysis with a stepwise entry of variables was designed to find out several potential variables for use in skeletal typing. The dentoalveolar compensation pattern of the skeletal types varied, especially with regards to the variables that indicated the inclination of incisors and the occlusal plane. Stepwise variable selection identified four variables: AB-MP, SN-AB, PMA and ANB. Discriminant analysis assigned a classification accuracy of $87.8\%$ to the predictive model. On the basis of these results, this study could provide rudimentary information for the development of diagnostic criteria and treatment guidelines for individual skeletal types.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.135-145
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• 2000

It is well known that there are different craniofacial skeletal groups in the same malocclusion types. The present study was performed to determine morphologic sub-groups in Korean children with Class III malocclusions, and to find out morphological differences between subgroups by means of a cross-sectional longitudinal cephalometric study. In this study, 135 children aged 6 to 14 year-old with untreated Class III malocclusions were selected. The samples were divided into two groups depending on the angulation of middle cranial fossa (MCF). That is, when the MCF of an individual was measured smaller than 40.3, he/she was tossed into mandibular protrusive-effect group(MREG), while when an individual was measured larger than 40.3, he/she was tossed into mandibular retrusive-effect group(MREG). Thereafter, the grouped samples were divided into 4 age groups(7, 9, 11 and 13 year-old). Thirty four linear and angular measurements on the tracings of lateral cephaloradiographs were measured, and the morphological characteristics and differences were compared and analysed by means of Wilcoxon test. It was found that Korean children with Class III malocclusions were divided into two groups, in which 39.3% were belonged in the MREG and 60.7% were in the MREG. In the MREG, anterior-posterior length of cranial base, nasomaxillary complex, maxilla and mandible were larger than the MREG. And although there was no difference in the total length of mandible (Co-Gn), mandibular body length (Go-Gn) was larger in the MREG during the majority of the observed periods. These results would suggest that a majority of the samples, 60.7%, demonstrated many of configurations of craniofacial skeletal relationships that can be found in the leptoprosopic faceform.

• Progress in Medical Physics
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• v.20 no.4
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• pp.253-259
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• 2009

We have developed standards based on international criterions for the quality control of dose tested by the measurement institutions of individual exposure doses through improving the reliability of data on the exposure dose of individuals working in radioactive environment and securing the accuracy and reliability of individual dose measurements. Laws related to radiation dose applied to domestic institutions refer to ANSI N13.11.1993, but currently, in U.S. and some other countries the measurement of radiation doses is based on ANSI N13.11.2001 that reduced test categories and tightened the standards. We made efforts to simplify the standards and to reduce the number of dosimeters required in experiment, and avoided preventing or hindering the use of future technologies not approved under the current law such as glass dosimeter and optical stimulation dosimeter. The Quality Management Manual of Radiation Dosimetry Service, Assessment Manual of Radiation Dosimetry Service Accreditation Program, and the Personnel Dosimetry Performance. Criteria for Testing are documents applicable in supervising laboratories.

• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.970-975
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• 2001

Objective : By conducing a review of clinical outcomes for patients with aneurysm treated using current microneurosurgical techniques and intensive care unit management, we speculated that grading systems based only on clinical condition or CT finding after admission failed to provide a significant stratification of outcome between individual grades of patients, because these systems did not include the factor for postoperative vasospasm. We hypothesized that postoperative blood flow velocity could have a significant impact on outcome prediction for patients surgically treated for intracranial aneurysms. Methods : We conducted a analysis on patient- and lesion-specific factors that might have been associated with outcome in a series of 55 aneurysm operations performed with measurements of blood-flow velocity with transcranial Doppler ultrasonography(TCD). In the new scale(NS) score system, 1 point is assigned additionally for the case with Hunt and Hess(H-H)/World Federation of Neurological Surgeons(WFNS) Grade IV or V, Fisher Scale(FS) score 3 or 4, aneurysm size greater than 10mm, patient age older than 60 years, blood-flow velocity higher than 120cm/sec, and posterior circulation lesion. By adding the total points, a 6-point scale score(score 0-6) is obtained. Results : Age of patient, size of aneurysm, clinical condition(H-H grade and WFNS), FS score, and blood flow velocity(TCD 1day after operation) were independently and strongly associated with long-term outcome. When NS scores were applied to 55 patients with at least 6 months follow-up, the correlation of individual scores with outcome was strongly validated the retrospective findings. Conclusion : It was speculated that TCD could be used to assess postoperative vasospasm and to monitor noninvasively the patients with aneurysmal SAH. This NS score system is easy to apply, divide patients into groups with different outcome, and is comprehensive, allowing for more accurate prediction of surgical outcome.

• Korean Journal of Remote Sensing
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• v.32 no.2
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• pp.73-86
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• 2016

In this study, an algorithm to estimate Aerosol Optical Thickness (AOT) over small cities during nighttime has been developed by using the radiance from artificial light sources in small cities measured from Visible Infrared Imaging Radiometer Suite (VIIRS) sensor's Day/Night Band (DNB) aboard the Suomi-National Polar Partnership (Suomi-NPP) satellite. The algorithm is based on Beer's extinction law with the light sources from the artificial lights over small cities. AOT is retrieved for cloud-free pixels over individual cities, and cloud-screening was conducted by using the measurements from M-bands of VIIRS at infrared wavelengths. The retrieved nighttime AOT is compared with the aerosol products from MODerate resolution Imaging Spectroradiometer (MODIS) aboard Terra and Aqua satellites. As a result, the correlation coefficients over individual cities range from around 0.6 and 0.7 between the retrieved nighttime AOT and MODIS AOT with Root-Mean-Squared Difference (RMSD) ranged from 0.14 to 0.18. In addition, sensitivity tests were conducted for the factors affecting the nighttime AOT to estimate the range of uncertainty in the nighttime AOT retrievals. The results of this study indicate that it is promising to infer AOT using the DNB measaurements over small cities in Korea at night. After further development and refinement in the future, the developed retrieval algorithm is expected to produce nighttime aerosol information which is not operationally available over Korea.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.4
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• pp.425-442
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• 2004

Statement of problem: A difficulty in achieving a passive-fitting prosthesis can be overcome by individual crown restoation of multiple implants. But individualized crown has another difficulty in control of contact tightness and stress distribution. Purpose: This in vitro study is to evaluate the stress distribution and the magnitude in the supporting tissues around Endopore implants with different crown lengths, interproximal contact tightness, and the splinting effects. Material & methods: Three Endopore implants($4.1{\times}9mm$) were placed in the mandibular posterior edentulous area distal to the canine and photoelastic model was made with PL-2 resin(Measurements Group, Raleigh, USA). Restorations were fabricated in two crown lengths: 9, 13 mm. For non-splinted restorations, individual crowns were fabricated on three custom-milled titanium abutments. After the units were cemented, 4 levels of interproximal contact tightness were evaluated: open, ideal($8{\mu}m$ shim stock drags without tearing), medium($40{\mu}m$), and heavy($80{\mu}m$). For splinted restorations, 3-unit fixed partial dentures were fabricated. This study was examined under simulated non-loaded and loaded conditions(6.8 kg). Photoelastic stress analysis was carried out to measure the fringe order around the implant supporting structure. Results: 1. When restorations were not splinted, the more interproximal contact tightness was increased among the three implants, the more stress was shown in the cervical region of each implant. When crown length was increased, stresses tended to increase in the apex of implants but there were little differences in stress fringes. 2. When nonsplinted restorations were loaded on the first or third implant, stresses were increased in the apex and cervical region of loaded implant. Regardless of interproximal contact tightness level, stresses were not distributed among the three implants. But with tighter interproximal contact, stresses were increased in the cervical region of loaded first or third implant. 3. When the nonsplinted restorations were not loaded, there were little stresses on the supporting structure of implants, but low level stresses were shown in the splinted restorations even after sectioning and soldering. 4. With splinted restorations, there were little differences in stresses between different crown lengths. When splinted restorations were loaded, stresses were increased slightly on the loaded implant, but relatively even stress distribution occurred among the three implants. Conclusions: Splinting the crowns of adjacent implants is recommended for Endopore implants under the overloading situation.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.5
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• pp.109-119
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• 2017

In the present study, to determine walking imbalance using the walking analysis method, where limitations in the existing walking analysis have been minimized, we propose a new walking analysis method that adopts the following: self-developed equipment to measure the angles of left-right hip joints and knee joints; a determination system using symmetry index (SI); and dynamic time warping (DTW) similarity analysis algorithm to analyze individual walking styles. Normal and imbalanced walking tests were conducted for 12 subjects without walking disorder. From the SI calculation to determine imbalanced walking, both the normal and imbalanced walking styles can be determined using the angle measurements of the left-right hip joints and knee joints. In the analysis of the individual walking styles, the similarities at the center of the lower back, left-right thighs, and dorsum of the feet of the 12 subjects in both normal and imbalanced walking cases were compared. From the similarity analysis of the measured values during the normal and imbalanced walking tests, I determined that the walking pattern does not maintain the same stance when the body parts move during walking.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.762-768
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• 2002

This study was conducted to evaluate the health status of elderly women who attended in a Health Promotion Program of the Seo-gu Health Center in Daegu. The study subjects were 158 elderly women (over 65 years) in an urban community. The subjects were investigated by means of individual interviews using a questionnaire, Blood tests for analyzing their biochemical status were carried out. The average age of the study subjects was 70.9 $\pm$ 2.3 years. Of the subject group 79.1% ranged in age from 65 to 74 year and 20.9% were over 75 years. With respect to health related factors, 23.4% of subjects drank alcoholic beverages and 15.2% of subjects currently smoke.The prevalence with chronic diseases was 51.9%, and 26.6% of the subjects were healthy. The diseases most frequently reported as having been or being treated were arthritis (38.1%), hypertension (21.4%), and diabetes (17.9%). The average height of subjects was below the standard established in the Korean Recommended Dietary Allowances, while the average weight was close to the standard. The means of systolic and diastolic blood pressure were 130.2 mmHg and 71.9 mmHg, respectively. The mean serum albumin level was 4.5 mg/d$\ell$ and the value of hemoglobin and hematocrit was 12.5 mg/d$\ell$ and 0.7%, respectively. The mean serum cholesterol level was 207.1 mg/d$\ell$ and the mean triglyceride level was 187.7 mg/d$\ell$. The serum lipid levels were higher then in those reported in research. The serum cholesterol levels of 71.5% of subjects were within the normal range. The GOT and GTP levels were within the moderate range. In conclusion, the health status of the elderly who attended the Health Promotion Program in the Seo-gu Health Center were very average. However, it was necessary to prepare a health management program to deal with the serum lipids so as to establish and maintain good health. When we carry out the health promotion program in a community, individual program Of adequate to health status should be developed more.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.27-34
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• 2013

Due to the increased interest in global warming, interest in forest resources aimed towards reducing greenhouse gases have subsequently increased. Thus far, data related to forest resources have been obtained, through the employment of aerial photographs or satellite images, by means of plotting. However, the use of imaging data is disadvantageous; merely, due to the fact that recorded measurements such as the height of trees, in dense forest areas, lack accuracy. Within such context, the authors of this study have presented a method of data processing in which an individual tree is isolated within forested areas through the use of LIDAR data and ortho-images. Such isolation resulted in the provision of more efficient and accurate data in regards to the height of trees. As for the data processing of LIDAR, the authors have generated a normalized digital surface model to extract tree points via local maxima filtering, and have additionally, with motives to extract forest areas, applied object oriented image classifications to the processing of data using ortho-images. The final tree point was then given a figure derived from the combination of LIDAR and ortho-images results. Based from an experiment conducted in the Yongin area, the authors have analyzed the merits and demerits of methods that either employ LIDAR data or ortho-images and have thereby obtained information of individual trees within forested areas by combining the two data; thus verifying the efficiency of the above presented method.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.398-422
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• 2017

Objectives: The major aim of this study is to construct the database of retrospective exposure assessment for crystalline silica through reviews of literatures in South Korea. Methods: Airborne concentrations of crystalline silica were collected using an academic information search engine, Research Information Service System(RISS), operated by the Korea Education & Research Information Service(KERIS). The key words used for the literature search were 'silica', 'crystalline silica', 'cristobalite', 'quartz' and 'tridymite'. A total number of 18 published documents with the information of crystalline silica level in air or bulk samples were selected and used to estimate retrospective exposures to crystalline silica. Weighted arithmetic mean(WAM) calculated across studies was summarized by industry type. Industries were classified according to Korea Standard Industrial Classification(KSIC) using information provided in the literature. Results: A total of 2,131 individual air sampling data measured from 1987 to 2012 were compiled. Compiled individual measurement data consisted of 827 respirable crystalline silica (RCS), 31 total crystalline silica(TCS), 24 crystalline silica(CS), 778 respirable dust(RD) and 471 total dust(TD). Most of RCS measurements(68.9%) were collected from 'cast of metals(KSIC 243)'. Comparing industry types, 'mining coal and lignite(KISC 051)' showed the highest WAM concentration of RCS, $0.14mg/m^3$, followed by $0.11mg/m^3$ of 'manufacture of other non-metallic mineral products(KSIC 239)', $0.108mg/m^3$ of 'manufacture of ceramic ware(KSIC 232)', $0.098mg/m^3$ of 'heavy construction(KSIC 412)' and $0.062mg/m^3$ of 'cast of metals(KSIC 243)'. In terms of crystalline silica contents in airborne dust, 'manufacture of other non-metallic mineral products(KSIC 239)' showed the highest value of 7.3%(wt/wt), followed by 6.8% of 'manufacture of ceramic ware(KSIC 232)', 5.8% of 'mining of iron ores(KSIC 061)', 4.9% of 'cast of metals(KSIC 243)' and 4.5% of 'heavy construction(KSIC 412)'. WAM concentrations of RCS had no consistent trends over time from 1994 ($0.26mg/m^3$) to 2012 ($0.12mg/m^3$). Conclusion: The data set related RCS exposure level by industries can be used to determine not only the possibility of retrospective exposure to RCS, but also to evaluate the level of quantitative retrospective exposure to RCS.