• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.393-400
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• 2020

Unlike conventional radiographic examinations, angiointerventional procedures have a high risk of radiation exposure to patients or operators due to prolonged radiation exposure time. This study was undertaken to examine effects of reducing the radiation risk by applying dose reduction fiber (DRF) shielding cloth during angiography. To investigate the properties of DRF shielding cloth, we measured the scattered radiation below and above a human phantom using a glass dosimeter, at site distances 10 cm away from the irradiated field. The results obtained reveal a 15 ~ 31% reduction of scattered radiation in the irradiation field, and 53 ~ 70% reduced radiation measured after phantom transmission. Taken together, our data indicate that application of DRF shielding cloth for radiation reduction at non-procedural sites during interventional procedure results in reduction of scattered doses to patients and operators, without affecting the medical examinations. We propose the use of DRF shielding during angiointerventional procedures, in order to reduce the risk of radiation exposure of patients and operators.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.11
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• pp.838-844
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• 2003

The noise and vibration reduction schemes of an industrial robot are studied. Experimental procedures are employed to examine the sources of robot noise. A parametric study is undertaken to observe the effects of each part such as gear, shaft and housing on the sound pressure level. After the part which mainly effects on the noise is proved, we propose countermeasures for reducing the noise and vibration of the robot system.

• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.813-822
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• 2010

We investigate a possible achievement in dimension reduction of time series via partially quantified principal component. Partial quantification technique allows us in modeling to accommodate artificial variable(s) of practical importance which is defined subjectively by the data analyst. Suggested procedures are described and in turn illustrated in detail by analyzing monthly unemployment rates in Korea.

• Journal of Korean Society for Quality Management
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• v.38 no.4
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• pp.491-503
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• 2010

This paper presents a research model, which identifies a relationship between medical error reduction, efficiency of organizational systems, and employee satisfaction with organizational support. The proposed model was tested through hypotheses, based on data collected from 210 respondents from the medical staff of large -sized (i.e., more than 500 beds) residential hospitals in cities of South Korea. The results of the study showed that medical error reduction is associated with corrective system and employee satisfaction with organizational support. Therefore, it is very important that organizations improve their employees' satisfaction by providing sufficient support (e.g., information support and sharing, work guide book, etc.) for their work. In addition, in organizational systems, the corrective system has positive relationship with medical error reduction. In terms of corrective procedures, leaders or managers can make improvements by providing and supporting a friendly work environment where errors may be reported without blame and discussed in order to be corrected.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.671-673
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• 2015

Before analyzing the images taken with a Mosaic CCD imager, the images have to reach a state which can be used for further scientific analysis. The transformation of raw images into calibrated images is called data reduction. Transforming HEavely Light into Images (THELI) is a nearly fully automated reduction pipeline software (Erben et al., 2005). This pipeline works on raw images to remove instrumental signatures, mask unwanted signals, and perform photometric and astrometric calibration. Finally THELI constructs a deep co-added mosaic image and a weight map. In this poster, THELI data reduction procedures will be reviewed and the reduction process for raw images of seven X-ray bright groups, extracted from GEMS groups (Osmond & Ponman, 2004) obtained by the Wide Field Imager (WFI) mounted on MPG/ESO telescope at La Silla in March 2006 will be discussed.

• Journal of Preventive Medicine and Public Health
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• v.49 no.4
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• pp.230-239
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• 2016

Objectives: We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea. Methods: To compare geographic variation in geographic units of analysis, we calculated the age-sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units. Results: Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures. Conclusions: Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

• Journal of radiological science and technology
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• v.44 no.5
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• pp.451-457
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• 2021

Recently, the number of interventional procedures has increased dramatically as an alternative of invasive surgical procedure and patient radiation exposure is also increasing accordingly. In this study, we evaluated the patient dose of major interventional procedures nationwide and we established our Korean database. With these results, we tried to suggest the reference dose level for major interventional procedures. We evaluated patent dose data in the field of interventional radiology from foreign countries. Measurement of radiation dose exposure for 11 major interventional procedures was conducted using embedded DAP meters in 10,006 patients from 47 hospitals, and reference level of each interventional procedure was suggested. The DRLs of each intervenional procedure are as follows: TACE 206(Gy·cm²), AVF 12(Gy·cm²), LE intervention 43(Gy·cm²), TFCA 122(Gy·cm²), Cerebral aneurysm coil embolization 214(Gy·cm²), PTBD 22(Gy·cm²), Biliary stent 60(Gy·cm²), PCN 7(Gy·cm²), Hickman catheter 2.1(Gy·cm²), Chemoport 1.4(Gy·cm²), BAE 104(Gy·cm²). Compared with the previously established DRL in 2012, the radiation dose decreased in all 10 interventional procedures. In the future, continuous publicity and education on the radiation dose reduction will be needed.

• Journal of Periodontal and Implant Science
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• v.49 no.2
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• pp.90-104
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• 2019

Purpose: The aim of this study was to evaluate clinical and radiographic changes and the survival rate after periodontal surgery using deproteinized bovine bone mineral (DBBM) with 10% collagen or DBBM with a collagen membrane in endo-periodontal lesions. Methods: A total of 52 cases (41 patients) with at least 5 years of follow-up were included in this study. After scaling and root planing with or without endodontic treatment, periodontal regenerative procedures with DBBM with 10% collagen alone or DBBM with a collagen membrane were performed, yielding the DBBM + 10% collagen and DBBM + collagen membrane groups, respectively. Changes in clinical parameters including the plaque index, bleeding on probing, probing pocket depth, gingival recession, relative clinical attachment level, mobility, and radiographic bone gains were evaluated immediately before periodontal surgical procedures and at a 12-month follow-up. Results: At the 12-month follow-up after regenerative procedures, improvements in clinical parameters and radiographic bone gains were observed in both treatment groups. The DBBM + 10% collagen group showed greater probing pocket depth reduction ($4.52{\pm}1.06mm$) than the DBBM + collagen membrane group ($4.04{\pm}0.82mm$). However, there were no significant differences between the groups. Additionally, the radiographic bone gain in the DBBM + 10% collagen group ($5.15{\pm}1.54mm$) was comparable to that of the DBBM + collagen membrane group ($5.35{\pm}1.84mm$). The 5-year survival rate of the teeth with endo-periodontal lesions after periodontal regenerative procedures was 92.31%. Conclusions: This study showed that regenerative procedures using DBBM with 10% collagen alone improved the clinical attachment level and radiographic bone level in endo-periodontal lesions. Successful maintenance of the results after regenerative procedures in endo-periodontal lesions can be obtained by repeated oral hygiene education within strict supportive periodontal treatment.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.4
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• pp.155-163
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• 2018

The development in air transport increases noise around the airport. In order to reduce the noise around the airport, International Civil Aviation Organization has made a lot of effort since the 1970s and Many countries, including South Korea, are implementing many noise reduction policies. This paper investigates those noise reduction policies of medium-sized airports with similar frequency to Gimpo, Jeju and Gimhae airports in South Korea and compares eleven airports in Europe, eleven airports in Asia and five airports in America, including Oceania. According to the research, European countries developed and applied the navigation procedure to avoid the noise area according to the characteristics of the airport. In Asia, there are not as many domestic noise reduction policies. In case of the United States, it provides information only on noise-sensitive areas around airports. After having investigated various policies, this research has examined the noise reduction policy of South Korea. It is concluded that new navigation procedures which reduce noise should be developed.

• Archives of Craniofacial Surgery
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• v.23 no.6
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• pp.269-273
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• 2022

Naso-orbito-ethmoidal (NOE) fractures are complicated fractures of the mid-face. The treatment of NOE fractures is challenging and a comprehensive treatment strategy is required. We introduce a case of NOE fracture treated with open reduction and suspension sutures. A 28-year-old woman presented with a unilateral NOE fracture. To reduce the frontal process of the maxilla, a suspension suture was made by pulling the fragment using a double arm suture via a transcaruncular incision. The suture thread was placed in the horizontal plane. Another suspension suture on the inferior orbital rim assisted reduction procedure, and they passed through the overlying skin. The reduction alignment could be finely adjusted by tightening the transcutaneous suture threads while checking the degree of bone alignment through the subciliary incision. The two suture threads were suspended using a thermoplastic nasal splint. An additional skin incision on the medial canthal area, which would have resulted in a scar, could be avoided. Four months postoperatively, computed tomography showed an accurate and stable reduction. The patient was satisfied with her aesthetic appearance, and functional deficits were not present.