• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.254-259
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• 2005

The heat and vibration effect is known to cause a serious deformation in linear motor system. The paper presents a heat and vibration characteristics that compare a advanced linear motor with developed linear motor through experiment and analyses. The heat in linear motor system is identified for experimental data and analytic data using the Finite Volume Method (FVM). Also, it shows that the optimum standard analyzed the acceleration patterns of the moving part cause the vibration source in linear motor. It presents the analyzed dynamics of linear motor in compliance with a deformation of the non-linear factor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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• pp.704-709
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• 1998

An automated calibration system of sound level meters was developed and tested. As a standard sound source, the speaker unit(Forstex FE208) cabineted by 440 * 390 * 490 mm$^{3}$(LHW) volume wood box was adopted. Including this source, the driving part was found out to have a good linearity of sound pressure output vs AC input. We use the Hybrid-Bisect, /Newton-Raphson method modified by the linearity as searching algorithm. Personal computer and program do the control, measurements, and calculations and finally do the accumulation of useful data and results. Several trials of automatic calibration using this developed system give reliable results.

• 환경위생공학
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• 제14권2호
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• pp.96-104
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• 1999

A questionary survey was conducted to investigate citizen's attitude to the treatment of food wastes in Miryang city. In this study, collection effectives was 87.8%, as 281 individuals among 320 individuals. After volume-base charge system, 86.8% of answers perform source separation and 60.9% of respondents separate everything of recycle goods. The majority of respondents discharge food waste using standard envelope. The biggest problems for deposition of the food wastes are offensive odor and worm for reasons of sanitation. Almost citizens think that the period of deposition suit from two days to three days. More than 90.0% of the citizens recognized that compost products made from food wastes and recognition of the people for the composting and composting facilities was affirmative. Majority of the respondents thought that the administration and the provincial government need activity publicity for the source separation fixations of the food wastes.

• 소음진동
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• 제8권5호
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• pp.879-886
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• 1998

An automated calibration system of sound level meters was developed and tested. As a standard sound source, the speaker unit(Forstex FE208) cabineted by 440$\times$390$\times$490 $\textrm{mm}^3$(LHW) volume wood box was adopted. Including this source, the driving part was found out to have a good linearity of sound pressure output vs AC voltage input. The Hybrid-Bisect/Newton-Raphson method modified by the linearity was adopted as a searching algorithm. Uisng GPIB interface, the console PC make the control, measurements, and calculations and finally make the accumulation of useful data and results automatically by the instructon in the program coded by C languate. Several trials of automatic calibration using this developed system give the reliable results.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1845-1850
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• 2003

The underground utility tunnels are important facility as a mainstay of country because of communication developments. The communication and electrical duct banks as well as various utility lines for urban life are installed in the underground utility tunnel systems. If a fire breaks out in this life-line tunnel, the function of the city will be discontinued and the huge damages are occurred. In order to improve the safety of life-line tunnel systems and the fire detection, the behaviors of the fire-induced smoke flow and temperature distribution are investigated. In this study we assumed that the fire is occurred at the contact or connection points of cable. Numerical calculations are carried out using different velocity of ventilation in utility tunnel. The fire source is modeled as a volumetric heat source. Three-dimensional flow and thermal characteristics in the underground tunnel are solved by means of FVM (Finite Volume Method) using SIMPLE algorithm and standard ${\kappa}-{\varepsilon}$ model for Reynolds stress terms. The numerical results of the fire-induced flow characteristics in an underground utility tunnel with different velocity of ventilation are graphically prepared and discussed.

• 한국방사선학회논문지
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• 제17권4호
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• pp.531-539
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• 2023

자체흡수는 환경 시료의 감마 분광 측정 정확도에 영향을 미치는 가장 중요한 요소이다. 특히, 샘플의 화학적 구성, 기하학적 모양, 두께, 밀도, 원자 번호, 샘플과 검출기 사이의 거리, 방출된 감마 광자의 에너지 및 샘플 내 습도 계수 또는 백분율과 같은 기타 요인에 의해 영향을 받는다. 보정 방법을 테스트하기 450 ml CRM 표준선원(9개 핵종) 마리넬리 비커를 사용하였다. 보정된 값들을 적용하여 환경시료 중 토양시료 5개를 밀도별로 측정하였다. 따라서, 자체흡수 값은 다소 크고 낮은 광자 에너지에 더 효과적임을 알 수 있다. 환경 시료의 경우 선원자체 흡수를 통한 전체 에너지 피크 효율은 샘플의 밀도에 크게 의존함을 확인하였다.

• 한국식품과학회지
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• 제37권3호
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• pp.352-359
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• 2005

인도페놀 적정법을 이용하여 성장기용 조제식 중 비타민 C 함량을 측정하는 과정 중의 측정불확도를 추정하기 위하여 분석결과에 영향을 주는 인자들을 파악하고 각각의 불확도를 산출하였으며, 불확도의 계산은 GUM(Guide to the expression of Uncertainty in Measurement)과 Draft EURACHEM CITAC Guide에 근거한 수학적 계산 및 통계처리 방법에 의해 처리하였다. 인도페놀 적정법에 의한 비타민 C 함량 측정시 measurand상의 uncertainty source로서 표준품 순도, 표준품 무게, 표준품 최종전량, 적정에 사용된 표준용액 부피, 인도페놀 용액에 의한 표준용액 적정, 시료의 무게, 시료의 최종전량, 적정에 사용된 시험용액, 인도페놀 용액에 의한 시험용액 적정 등이 작용하였으며, uncertainty source에 영향을 주는 세부인자인 uncertainty parameter로서는 저울의 안정성, 분해능, 재현성, 1 mL 피펫, 5 mL마이크로피펫, 100 mL 메스플라스크의 눈금읽기, 내부교정 등이 작용하였다. 소급성 유지를 위해 비타민 C 함량과 측정불확도가 보장된 인증표준물질인 Infant Formula SRM 1846을 사용하여 비타민 C 함량을 측정한 결과값은 $108.4{\pm}1.7mg/100g$로 인증값인 비타민 C 함량 $114.6{\pm}6.6mg/100g$의 범위내로 측정되었으며, CRM에서 보장된 균일성과 실험오차를 고려하면 유사한 결과가 산출되었음을 알 수 있다(p<0.05). 이와 같은 소급성 검증 후 시중에 유통 중인 성장기용조제식의 비타민 C 함량을 분석하기 위하여 시료량을 달리 하여 측정불확도를 계산한 결과, 본 연구에서는 시료를 최소한 5g은 취해야 결과값 및 측정불확도가 $56.7{\pm}2.44mg/100g$으로서 5%이하로 측정불확도를 유 지할 수 있었다. 이와 같이 측정불확도를 고려하여 서로 상이한 분석방법간의 신뢰성을 비교 검증하여야 하며, 획일적으로 단순히 적정법과 HPLC법을 비교해서는 다소 무리가 있을 것으로 판단된다. 본 연구에서와 같이 측정불확도를 고려하여 분석에 영향을 줄 수 있는 요인들을 최소화한다면 HPLC와 같은 고가의 정밀분석기기를 구비하지 못한 실험실에서도 인도페놀 적정법에 의한 비타민 C 분석방법을 이용하여 신뢰성있는 측정결과를 얻을 수 있을 것으로 사료된다.

• Nuclear Engineering and Technology
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• 제43권6호
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• pp.583-592
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• 2011

The radiological characteristics for waste classification were assessed for neutron-activated decommissioning wastes from a CANDU reactor. The MCNP/ORIGEN2 code system was used for the source term analysis. The neutron flux and activation cross-section library for each structural component generated by MCNP simulation were used in the radionuclide buildup calculation in ORIGEN2. The specific activities of the relevant radionuclides in the activated metal waste were compared with the specified limits of the specific activities listed in the Korean standard and 10 CFR 61. The time-average full-core model of Wolsong Unit 1 was used as the neutron source for activation of in-core and ex-core structural components. The approximated levels of the neutron flux and cross-section, irradiated fuel composition, and a geometry simplification revealing good reliability in a previous study were used in the source term calculation as well. The results revealed the radioactivity, decay heat, hazard index, mass, and solid volume for the activated decommissioning waste to be $1.04{\times}10^{16}$ Bq, $2.09{\times}10^3$ W, $5.31{\times}10^{14}\;m^3$-water, $4.69{\times}10^5$ kg, and $7.38{\times}10^1\;m^3$, respectively. According to both Korean and US standards, the activated waste of the pressure tubes, calandria tubes, reactivity devices, and reactivity device supporters was greater than Class C, which should be disposed of in a deep geological disposal repository, whereas the side structural components were classified as low- and intermediate-level waste, which can be disposed of in a land disposal repository. Finally, this study confirmed that, regardless of the cooling time of the waste, 15% of the decommissioning waste cannot be disposed of in a land disposal repository. It is expected that the source terms and waste classification evaluated through this study can be widely used to establish a decommissioning/disposal strategy and fuel cycle analysis for CANDU reactors.

• 한국물환경학회지
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• 제20권5호
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• pp.415-421
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• 2004

Litter wastes on highway runoff are gradually being considered one of the major pollutants of concern in protecting the integrity of receiving waters for beneficial use. The California State Water Resources Control Board has identified in their 303(d) list at least 36 water bodies where trash or litter is considered a pollutant of concern. The first TMDL adopted by the Region 4 (Los Angeles area) of the California State Water Quality Control Board was for trash in the Los Angeles River. The first flush characteristic study was developed to obtain first flush water quality and litter data from representative stormwater runoff from standard highway drainage outfalls in the Los Angeles area. Total captured gross pollutants in stormwater runoff were monitored at six Southern California highway sites over two years. The gross pollutants were 90% vegetation and 10% litter. Approximately 50% of the litter was composed of biodegradable materials. The event mean concentrations show an increasing trend with antecedent dry days and a decreasing trend with total runoff volume or total rainfall. Event mean concentrations were ranged 0.0021 to 0.259g/L for wet gross pollutants and 0.0001 to 0.027g/L for wet litters. The first flush phenomenon was evaluated and the impacts of various parameters such as rainfall intensity, drainage area, peak flow rate, and antecedent dry period on litter volume and loading rates were evaluated. First flush phenomenon was generally observed for litter concentrations, but was not apparent with litter mass loading rates. Litter volume and loading rates appear to be directly related to peak storm intensity, antecedent dry days and total flow volume.

• 한국관개배수논문집
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• 제18권1호
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• pp.4-17
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• 2011

The standard design methodology was suggested to construct wetland system for reducing non-point source pollution from Saemangeum reclaimed paddy land. To set for the design flow and concentrations, runoff and water quality survey were conducted during the irrigation period in 2008 at Gyehwa reclaimed paddy land located at near Saemangeum lake. It is rational that 1ha is the optimum constructed wetland size. To meet this size, the moderate drainage area of reclaimed paddy field was 50ha under the conditions that rainfall is 30mm, average runoff coefficient is 0.83, and runoff capture ratio is 0.6. At these condition, the runoff volume from 50ha was 10,520 $m^3/d$ including base flow during irrigation period. To select the optimum wetland system, several case studies were conducted by focusing on the tidal reclaimed land areas having wetland systems in Seokmun. Pond-Wetland system was selected as the standard model because of showing the highest reduction efficiency. Single variable regression equation were delivered to estimate effluent water concentrations from the designed wetland by using long-term monitoring data from the Seokmun experiment site. The effluent concentration from the designed wetland using these equation were showed moderately range.