• 설비공학논문집
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• 제3권1호
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• pp.34-41
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• 1991

The effect of flow conditions on flow measurement is difficult to identify from the inherent characteristics of the flowmeters and flow standard system. A new experimental approach has been attempted to detect the turbine meter error due to inlet flow conditions. In this try not only the design of the turbine meter package but also the data analysis method was altered. It was found that k factor slope of the turbine meter responds to the change of flow conditions in the test line with higher sensitivity than the degree of the data scattering. The flow standard system of $0.1m^3/s$ was chosen for the investigation. The systematic and random error of the system were less than ${\pm}0.08%$ and ${\pm}0.13%$ respectively.

• 자동차안전학회지
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• 제11권4호
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• pp.22-27
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• 2019

In this paper, the vibration load and analysis results for automotive battery supporter were performed to provide efficient vibration tolerance performance prediction methods for single-product vibration tolerance testing, and the major influencing factors and considerations for setting up single-unit vibration tolerance tests were reviewed. A common applicable standard load was applied to efficiently predict the performance of single-unit vibrations through the frequency response analysis technique. The results similar to test results can be predicted by checking vulnerable parts of the vehicle components for vibration loads and applying scale factor to standard loads. In addition, it was confirmed that the test conditions with a frequency generating the same durability severity as the endurance test are needed for accurate prediction of the durability of the single-unit vibration tolerance test conditions, and the acceleration and frequency with the conditions that there is no significant nonlinear phenomena in the vibration system are established during the single-unit vibration tolerance test conditions.

• 대한설비공학회지:설비저널
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• 제13권1호
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• pp.48-63
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• 1984

Standard Building Operation Conditions(SBOC) is to describe typical conditions under which a building would operate during the coulee of a day In order to develop SBOC profiles for office building, we surveyed the operating conditions of randomly selected 20 existing office buildings in Seoul by means of enquetes, and made SBOC profiles. SBOC profiles consist of human occupancy profile, light ins usage profile, system schedule and domestic hot water profile etc. SBOC profiles will be used as input data of DOE-2 computer program to estimate DER(Design Energy Requirements) and to develop EBL (Energy Budget Level), SBOC profiles are not meant to be exact description of how a building will actually be used by its respective users. Rather they are intended to be reasonable typical project ions of how buildings might be used.

• Wind and Structures
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• 제24권5호
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• pp.465-480
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• 2017

Modelling an equilibrium atmospheric boundary layer (ABL) in computational wind engineering (CWE) and relevant areas requires the boundary conditions, the turbulence model and associated constants to be consistent with each other. Among them, the inflow boundary conditions play an important role and determine whether the equations of the turbulence model are satisfied in the whole domain. In this paper, the idea of modeling an equilibrium ABL through specifying proper inflow boundary conditions is extended to the SST $k-{\omega}$ model, which is regarded as a better RANS model for simulating the blunt body flow than the standard $k-{\varepsilon}$ model. Two new sets of inflow boundary conditions corresponding to different descriptions of the inflow velocity profiles, the logarithmic law and the power law respectively, are then theoretically proposed and numerically verified. A method of determining the undetermined constants and a set of parameter system are then given, which are suitable for the standard wind terrains defined in the wind load code. Finally, the full inflow boundary condition equations considering the scale effect are presented for the purpose of general use.

• 한국의류학회지
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• 제24권1호
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• pp.77-86
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• 2000

Purposes of this study were firstly to refine the measurement technique of tactile sensation and sensibility induced by touching the fabrics and secondly to investigate the differences of tactile sensibility depending on environmental conditions and the type of polyester fabrics. The environmental conditions were controlled at 20$\pm$1$^{\circ}C$, 65$\pm$3%RH(standard) and at 29$\pm$1$^{\circ}C$, 75$\pm$3%RH(warm & humid). As results, three factors were extracted from factor analysis of sensory assessment scale. The first factor was thickness and weight, the second one was surface-related property and the third one was stiffness in both environments. Depending on the environmental conditions, heat and moisture-related sensations such as [cold], [damp] and [dry & drapable] were affected significantly. Regression equations with the sensation descriptors were developed for the prediction of tactile sensibility(R2>.89). While the most efficient descriptor was [thin & flexible] in the standard environmental conditions, that was [dry & drapable] in the warm & humid environmental condition.

• 무역상무연구
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• 제13권
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• pp.495-513
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• 2000

In this paper, I examined the terms of letter of credit and standard for examination of documents. In connection with the test of standard, I reviewed the bank's reasonable care, inconsistence and linkage between documents, non-documentary conditions and the treatment of discrepant documents. Traditionally credit law is founded on two principles such as the standards of strict of compliance and substantial compliance, but these standards are not consistency. Moreover although the Uniform Customs and Practice for Documentary Credits(UCP) introduces a new standard for examination of documents by incorporating international banking practice, the standards for documentary compliance have created ambiguity. Accordingly, I suggest that the standard requires strict compliance between party concerned in letter of credit transactions but only requires international standard banking practice in customer relationship. Therefore the standard and the specific guideline should be prescribed in the next version of the UCP.

• 한국농공학회논문집
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• 제64권4호
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• pp.11-20
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• 2022

Currently, the operation rule of agricultural reservoirs in case of drought events follows the drought forecast warning standard of agricultural water supply. However, it is difficult to preemptively manage drought in individual reservoirs because drought forecasting standards are set according to average reservoir storage ratio such as 70%, 60%, 50%, and 40%. The equal standards based on average water level across the country could not reflect the actual drought situation in the region. In this study, we proposed the improvement of drought operation rule for agricultural reservoirs based on the percentile approach using past water level of each reservoir. The percentile approach is applied to monitor drought conditions and determine drought criteria in the U.S. Drought Monitoring (USDM). We applied the drought operation rule to reservoir storage rate in extreme 2017 spring drought year, the one of the most climatologically driest spring seasons over the 1961-2021 period of record. We counted frequency of each drought criteria which are existing and developed operation rules to compare drought operation rule determining the actual drought conditions during 2016-2017. As a result of comparing the current standard and the percentile standard with SPI6, the percentile standard showed severe-level when SPI6 showed severe drought condition, but the current standard fell short of the results. Results can be used to improve the drought operation criteria of drought events that better reflects the actual drought conditions in agricultural reservoirs.

• 한국자동차공학회논문집
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• 제6권3호
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• pp.26-33
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• 1998

An experimental study has been conducted for the three-dimensional in-cylinder swirl flow under steady conditions. Velocity fields are measured by using an LDV at various valve lifts. Effects of geometry of inlet ports on swirl flows are investigated for standard and helical ports. Swirl distributions evaluated from velocity measurements are compared with those obtained from an impulse torque swirl meter. Results show that the helical port generates more intensive swirl than the standard one but it causes red- uction in air flow coefficient. At the lower valve lift, no significant difference is observ- ed in non-dimensional swirl values between two ports because of limited pre-swirl effect, while it becomes significant as the valve lift increases.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.515-518
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• 2005

In recent years, many research works have been carried out in order to obtain a more controlled durability and long-term performance of concrete structures exposed to chloride environments. In particular, the development of new procedures for probability-based durability analysis and design has been proved to be very valuable. To carry out the procedures described above, the statistical properties of design valuables such as diffusion coefficient of chloride ion, surface chloride concentration, and chloride threshold value etc. should be known. For this purpose, this paper presents the statistical properties of the diffusion coefficient of chloride ion such as mean value and standard deviation with water-cement(w/c) ratio and curing conditions, respectively. It was observed from the test that the standard deviation for the diffusion coefficient of chloride ion was found to be small with decrease in the w/c ratio irrespective of curing conditions and that of standard curing was found to be smaller than that of field curing.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.927-932
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• 2000

Recently, construction vibration has caused annoyance for a number of dwellers in nearby construction field and that induced from operating of large construction equipment, has become a very serious issue in our living environment. But, construction vibration standard of our living environment. But construction vibration standard of our country is efficient. Especially, directly blow method(diesel piling method, oil pressure method, etc) has caused much problems of highly impactive vibration. Construction works, in order to solve these problem, will be used SIP(Soilcement Injected Precast Pile) method of low vibration equipment. In this point, this study attempts to survey on the characteristics of piling vibration by SIP method for various earth conditions in construction field. And this study intends to get the basic data to establish a standard about construction vibration.