• 한국기록관리학회지
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• 제12권3호
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• pp.7-28
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• 2012

정보량의 빅뱅, 전자기록물의 대량 생산, 다양한 기록매체의 출현 등 급변하는 기술변화 환경 하에서 안정적인 전자기록 관리체계 구축 운영을 위해서는 적극적으로 관련 기술 흐름과 발전 방향을 이해하고 준비 대응해나가는 것이 매우 중요하다. 이에 본 연구에서는 우선 현재 기록매체와 관련된 기록관리 법령과 표준 등의 미비점을 도출하였다. 제도의 개선 방향을 모색하고자 기록매체와 관련된 기술 현황과 기록매체의 수명과 관련된 연구 결과들을 분석하는 동시에 미국, 영국 등 해외 사례들을 살펴보았다. 이와 같은 분석 결과를 바탕으로 본 연구에서 기록매체 종류의 확대, 기록매체 선택 요소의 수정 보완, 기록매체의 효율적인 관리 방안 등 제도적인 개선 방향을 제시하였다.

• Clinical and Experimental Pediatrics
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• 제57권1호
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• pp.35-40
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• 2014

Purpose: Height-specific blood pressure (BP) is the standard parameter used to diagnose childhood hypertension. However, there has been some argument that weight may be a better variable than height in the reference BP standards. Therefore, before assessing the BP status using the reference BP standards, a basic understanding of the fundamental association of weight and height with BP is required. Methods: In the present study, we analyzed the correlation of BP with height and weight in Korean adolescents (age, 10-19 years), using data from the Korean National Health and Nutrition Examination Surveys (2009-2011). Results: Systolic BP (SBP) was more closely correlated with weight than with height in the normal weight (body mass index [BMI], ${\leq}85th$ percentile) and overweight (BMI, >85th percentile) groups and in the normal waist circumference (WC, ${\leq}90th$ percentile) and high WC (>90th percentile) groups in both sexes. Diastolic BP (DBP) had a higher correlation with height than with weight in the normal weight and normal WC groups, whereas weight was more closely associated with DBP than height in the overweight and high WC groups in both boys and girls. Conclusion: In Korean adolescents, weight had a greater effect on SBP than height in both the normal weight and overweight groups. DBP was mainly affected by height in the normal weight group, whereas weight was the major determinant of DBP in the overweight group. Therefore, it may be necessary to consider weight in the establishment of reference BP standards.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.347-347
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• 2011

Secondary ion mass spectrometry (SIMS) was fascinated by a quantitative analysis and a depth profiling and it was convinced of a in-depth analysis of multi-layer films. Precision determination of the interfaces of multi-layer films is important for conversion from the original SIMS depth profiling to the compositional depth profiling and the investigation of structure of multi-layer films. However, the determining of the interface between two kinds of species of the SIMS depth profile is distorted from original structure by the several effects due to sputtering with energetic ions. In this study, the feasibility of 50 atomic % definition for the determination of interface between two kinds of species in SIMS depth profiling of multilayer films was investigated by Si/Ge and Ti/Si multi-layer films. The original SIMS depth profiles were converted into compositional depth profiles by the relative sensitivity factors from Si-Ge and Si-Ti alloy reference films. The atomic compositions of Si-Ge and Si-Ti alloy films determined by Rutherford backscattering spectroscopy (RBS).

• Current Optics and Photonics
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• 제7권4호
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• pp.435-442
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• 2023

These days, the size of a reflective telescope has been increasing for astronomical observation. An additional optical system usually assists a large ground telescope for image analysis or the compensation of air turbulence. To guide collimated light to the external optical system through a designated path, a coudé mirror is usually adopted. Including a collimator, a coudé mirror of a ground telescope is affected by gravity, depending on the telescope's pointing direction. The mirror surface is deformed by the weight of the mirror itself and its mount, which deteriorates the optical performance. In this research, we propose an optimization method for the coudé mirror assembly for a 1-m class ground telescope that minimizes the gravitational surface error (SFE). Here the mirror support positions and the sizes of the mount structure are optimized using finite element analysis and the response surface optimization method in both the horizontal and vertical directions, considering the telescope's altitude angle. Throughout the whole design process, the coefficients of the Zernike polynomials are calculated and their amplitude changes are monitored to determine the optimal design parameters. At the same time, the design budgets for the thermal SFE and the mass and size of the mount are reflected in the study.

• 한국산업보건학회지
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• 제20권3호
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• pp.203-215
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• 2010

This study is an overview of toxicities and measurement techniques of ultrafine particles (UFPs), and their exposure controls. UFPs are ubiquitous in many working situations. Exposure to UFPs is possibly causing adverse health symptoms including cardio-respiratory disease to humans. In order to measure exposure levels of airborne UFPs, there are current available measurement guidelines, instruments and other techniques (i.e. contour mapping, control banding). However, these risk assessment techniques including measurement techniques, controls and guidelines are dependent on background levels, metrics (e.g. size, mass, number, surface area, composition), environmental conditions and controls. There are no standardized measurement methods available and no generic and specific occupational exposure standards for UFPs. It is thought that there needs to be more effort to develop Regulations and Exposure Standards for generic UFPs should be based on more exposure data, health surveys, toxicological data and epidemiological data. A carefully considered hierarchy of controls can also reduce the maximum amount of airborne UFPs being emitted from diverse sources in industries.

• 한국정밀공학회지
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• 제31권1호
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• pp.67-73
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• 2014

A reliability evaluation or prediction can be defined as MTBF which stands for mean time between failures (Exclusively for repairable failures). Spindle system has huge effect on performance of machine tools and working quality as well as is required of high reliability. Especially, it takes great importance in producing automobiles which includes a large number of working processes. However, it is unusually difficult to predict reliability because there are lack of data and research about reliability of spindle system. Standards and methods of examinations for reliability evaluation of machine tools are scarce at local and abroad as well. Therefore, this research is meant to improve the reliability of spindle system before mass produced with developing standards of reliability and methods of examinations through FMEA to assess reliability of spindle system in prototype stages of developing high speed spindle system of machining center.

• Journal of Radiation Protection and Research
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• 제25권2호
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• pp.109-114
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• 2000

The SI unit of specific absorption rate (SAR) in W/kg in the electromagnetic (EM) field as non-ionizing radiation is exactly same as the SI unit of absorbed dose rate in Gy/s in the ionizing radiation field. The SI unit of both physical quantities can be expressed in $[m^{\cdot}s^{-3}]$. Where, the unit of absorbed dose, Gy stands for Gray. In EM biological interactions, the SAR equations are derived and the characteristics of EM field energy absorption in terms of the SAR are discussed and described on the mathematical basis.

• 산업기술연구
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• 제25권A호
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• pp.133-139
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• 2005

In this study, as MBBR(Moving Bed Biofilm Reactor) process using waste tire media is suggested for retrofitting with advanced wastewater treatment and the removal property of organic matter and nutrient and the capacity of media are evaluated through long-term operation with pilot plant following seasons, the application capacity of retrofitting with MBBR process to a existing wastewater treatment is studied. As a result of the long-term operation of the process, it is proved that there is no loss and abrasion of media, and also that it is possible to secure the sufficient attached bio-mass. The values of organic matter and nutrient in effluent are suitable for the strict discharged water quality standards in every season including winter.

• Journal of Radiation Protection and Research
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• 제16권2호
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• pp.7-16
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• 1991

감마선 조사선량의 국가표준을 확립하기 위하여 Co-60 감마선에 대한 조사선량률 절대 측정을 수행하였고 그 값이 갖는 오차한계를 분석 평가하였다. 측정기로는 고순도 흑연으로 제작된 원통형 이온전리함을 사용하였고 이온화 전류 측정은 vibrating reed 증폭기를 사용한 전하모드법에 의해 수행되었으며 관련 물리상수 및 각종 관련 보정인자를 평가하여 이온화 전류 측정값으로부터 조사선량률을 결정하였다.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.696-700
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• 1993

Gold bonding wire of 0.076 mm in diameter used in semiconductor industry, is dissoved in aqua regia. The solution is then evaporated to near dryness several times with a few drops of HCl added to prepare the final sample solution in 5% HCl. The gold matrix is separated from trace impurities by controlled potential deposition. The whole electrolysis has been carried out inside a clean bench. An optimum potential is found to be +0.25 V to give more than 99.9% Au matrix removal with better than 90 analytes remaining in the electrolyte solution. Isotope dilution calibration is employed to get the best accuracy and precision. Analytical results are presented with determination limits of the analytical method.