• 상하수도학회지
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• 제25권2호
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• pp.213-221
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• 2011

The purpose of sewer system is to separate rain water from sewage water. Through this, it is possible to prevent the flood and preserve public water territory. For the past few years, many problems of the sewer system have been solved by the execution of sewer rehabilitation project. However, they still exist in sewer system caused by I/I, which are divided into infiltration and inflow. Infiltration means the rain water and underground water that infiltrate through breakage point on pipes, inflow means the water that flows in through misconnection on pipes. This study shows how the I/I calculation has changed according to the new standardized manual and identifies the I/I difference between the new calculation and the existing one. Through the analysis on the two calculation methods we examined the appropriacy of the new method by comparing it to the old one. The result points out that the new standardized manual is more appropriate than the old in aspect of objectivity and reproducibility(establish standardization), rationality(alteration of inflow unit).

• 대한조선학회지
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• 제15권1호
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• pp.7-9
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• 1978

In this calculation of statical stability of a ship, mechanical integrator was used most popularly and the direct calculation method such as a Barn's wedge method was also adopted in some cases. Both of the above method was developed for manual calculation which include mechanical integration or drafting procedure on body plan. Therefore, the computerization of stability calculation by the above method is very difficult. In this paper a simplified method for stability calculation is suggested, with based on hydrostatic data and immerged wedged characteristics.

• 한국환경농학회지
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• 제42권4호
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• pp.444-449
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• 2023

The current study involved the calculation of air pollutant emission factors (EFs) generated from the incineration of agricultural residues. The process included sample collection, weight measurement, moisture measurement, incineration system configuration, and concentration measurement. The average CO emission factor of gaseous air pollutants from the incineration of barley and wheat agricultural residues was calculated as 0.08289 kg/kg and 0.06665 kg/kg, respectively, whereas the average NO_X emission factor for barley and wheat agricultural residues was determined to be 0.00518 kg/kg and 0.00185 kg/kg, respectively. In the existing air pollutant emission calculation manual, the EF is presented only for barley. Therefore, in this study, we have introduced the EF for wheat, previously absent in the calculation manual. Additionally, the air pollutant calculation manual presents the EF of air pollutants as one value, but in this study, EF values corresponding to 2.5% and 97.5% were presented in consideration of the distribution of experimental values as shown in EMEP/EEA data.

• 한국안전학회지
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• 제8권2호
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• pp.87-93
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• 1993

Many methods to assess hazards caused by the risks increased with the growth of petrochemical industry. The manual of International Atomic Energy Agency which was much more applied to quantitative analysis of the real situation and the CPQRA is introduced to verify the theoretical background of this manual. Than other methods, as a result, we can see that this manual, which is simple to use and requires a little information, shows similar results to those of calculation by numerical formula. Also, the program code of this manual was materialized and if it is possible to obtain adequate parameters to our circumstance, the manual will be quite useful in early risk analysis.

• Journal of the Optical Society of Korea
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• 제18권1호
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• pp.23-31
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• 2014

Recently, the number of camera companies that produce commercializing interchangeable lens systems such as digital single lens reflex (DSLR) and compact system camera (CSC) lenses has been gradually increasing. These interchangeable lenses have various kinds of lenses with distinct specifications. In particular, the distance window among these specifications is the function most preferred by customers. Mechanical manual zoom and manual focus in these high end camera lenses with a distance window are in particular desirable specifications and are required for product quality. However, the AF lens group is linked to the zoom cam and moves. Because the AF lens group moves along with the object distance, we can not realize the distance window with only zoom locus calculation. In this paper, in order to solve the problem, we suggest an optical calculation method for a corrected AF zoom cam for an interchangeable lens with a distance window to achieve product differentiation and analyze the error in the calculation.

• 한국화재소방학회논문지
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• 제29권1호
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• pp.73-79
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• 2015

스프링클러 설비의 설계방법은 크게 3가지로 분류한다. 가지관을 서로 연결하여 사다리형태로 배관을 설치하는 Grid형과 가지관은 연결하지 않고 교차배관만을 연결하는 Loop형 그리고 가장 일반적으로 사용되는 Tree형이 있다. 이 중 Grid형은 아주 간단한 것을 제외하고는 컴퓨터프로그램으로 마찰손실을 계산하여야 하지만 Loop형의 경우는 프로그램의 도움 없이 설계자가 직접 계산하여 마찰손실에 따른 필요압력과 소요유량을 산출할 수 있다. Loop형 설비의 경우 소화수 공급이 2방향으로 분리되어 마찰손실이 작아지고 헤드간 방출압력의 차이가 Tree형보다 작게 되어 살수분포가 우수하게 되며 작은 마찰손실에 의한 소구경의 배관을 사용하여 자재비와 인건비가 절감되므로 Loop형에 의한 스프링클러의 설계가 Tree형 설비에 비해 성능과 경제성에서 우수한 설계 방법이다. 하지만 Loop형 설비의 설계는 설계방법이 잘 알려져 있지 않아 거의 이루어지지 않고 있다. 본 논문에서는 Tree형 보다 우수한 Loop형 설비의 설계방법을 설명하여 많은 설계자가 성능과 경제면에서 우수한 Loop형 설계를 쉽게, 널리 사용하게 하고자 하였다.

• 문화기술의 융합
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• 제9권6호
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• pp.1049-1055
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• 2023

농업용 드론을 이용한 방제 작업의 경우 그 경제적 효율성으로 인해 활용도가 증가하고 있으나, 작업자의 숙련도에 따라 효과의 차이가 발생한다. 이에 본 연구에서는 스마트 운영 모드를 적용하여, 수동 비행 모드에서 제어의 단점을 보완하고 이에 대한 수치적 모델을 제안하고, 선행 연구와 비교 검증을 통해 실험적 검증을 수행하였다. 그 결과 농업용 방제 드론들의 분사 시간 및 방제면적을 도출하였고, 수치적 모델과 유사성이 높은 방제용 드론을 선정하여 실험적으로 검증하였다. 이를 통해 수동 비행 모드보다 스마트 운영 모드 적용 시 살포 면적 및 작업(살포 균일도 및 작업 효율)이 상대적으로 효과적인 것을 확인하였다.

• 대한조선학회지
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• 제14권3호
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• pp.1-4
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• 1977

The computer aided ship design and construction has become very popular one in a ship yard recently. For one of such a purpose a program is developed with Aitken's iterative interpolation method. From the sample calculation we can conclude that the program has a reliable acquracy for the calculation of hydrostatic data or loading manual. And also the program can be applicable to a ship construction by careful selecting of input data.

• Radiation Oncology Journal
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• 제5권2호
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• pp.165-168
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• 1987

The generalized Bathe method, proposed by Webb and Fox, which is a method of calculation of dose correction factor for the purpose of heterogeneous tissue, is complex even for a few kind of tissues. The method was modified for the purpose of getting a simple method that divide the multilayer of heterogeneous tissues into some groups of adjacent-tissue pairs. This new method could reduce the number of exponential terms and the time for calculating the dose correction factors by manual and computer calculation.

• 한국안전학회지
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• 제10권1호
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• pp.56-63
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• 1995

Two methods of the numerical method of CPQRA(Chemical Process Quantitative Risk Analysis) and the manual method of IAEA(International Atomic Energy Agency) were used to estimate the individual risk and societal risk around the chemical plant. Where, the CPQRA is introduced to verify the theoritical background of the manual of international atomic energy agency. The Gaussian plume model which has a weather stability class D with velocity of 5m/s was applied to calculate dispersion of hazard material. Also, 8-point method was employed to the effects of accidents for wind distribution. Furthermore, historical record, FTA(Fault Tree Analysis) and ETA(Event Tree Analysis) were used to estimate the probability or frequency of accidents. Eventually, the individual risk shows isorisk contour and the societal risk shows F-N curve around hazard facility, especially in chemical plants. Caulculated results, which both individual and societal risk, by using IAEA manual show simillar results to those of calculation by numerical method of CPQRA.