• 대한기계학회논문집B
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• 제25권4호
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• pp.561-571
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• 2001

The standard uncertainty of flowrate measurement is obtained by combining that of independent variables. Gravimetric and volumetric method were applied to determine the flowrate and the standard uncertainties of flowrate measurement by both methods were evaluated in accordance with the procedure recommended by International Organization for Standardization. The combined standard uncertainties of determining the flowrate were estimated from the sensitivity coefficient and the standard uncertainty of independent variables. For practical application, the methods for evaluating and expressing uncertainty in flow measurement were discussed. It was found that the uncertainties of the weighing and time measurement in gravimetric method, the volume and time measurement in volumetric method have dominant influence on that of flowrate measurement. With the quantitative analysis of the sensitivity coefficient, the contribution of the each variable uncertainty to the combined standard uncertainty of flowrate measurement is shown clearly.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.193-200
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• 2001

In this study, the methodology to develop a data model for steel box girder bridge based on STEP part 104 is presented. The concept of STEP and the schema of part 104 are briefly reviewed, and then the procedure of data model standardization is described. A new data model for steel box girder bridge is developed by incorporating with not only the geometric and topological representation schema of the part 42 but also the representation structure information of the part 43 and the detailed finite element analysis information of the part 104. The prototype of integrated finite element analysis(FEA) system by interfacing STEP physical file is also presented. The applicability of developed data model for FEA is verified by preprocessor system of FEA.

• 한국해양공학회지
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• 제13권2호통권32호
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• pp.26-34
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• 1999

Two types of barge, container and tanker vessels, are designed with specific dimensions for canal-coastal shipping in Kyung-In canal and Yellow Sea region. The principal dimensions of barges are determined by considering the environment of Kyung-In canal and Yellow Sea. The selection of structure type and structure type and strength confirmation is conducted by the technical rules of Korean Register of Shipping. For the structural analysis of designed barges, the semi-direct stuctural analysis is carried out with using MSC NASTRAN software. Applying identical dimensions to both vessels, the standardization of structural design and analysis procedure are introduced.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 가을 학술발표회 논문집
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• pp.275-280
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• 2001

Although important developments have taken place since ESOPT 1974 both with respect to the test method as well as the interpretation of the results, many uncertainties still remain in the Standard Penetration Test(SPT). The main pitfall of SPT is that it has not been standardized differing from its terminology and further, the possibility of standardization is very low in practice. Therefore, lack of knowledge on the equipment and method of SPT tends to cause some errors in interpretation of the results. It Is especially important to understand this tendency in domestic design, because most foundations are designed based on SPT results only. Many researchers have made an effort to minimize the uncertainties of SPf in Korea, it is not cleary defined what the most effective method of execution and interpretation of SPT Some uncertainties which many geotechnical engineers encounter in practice are introduced to discuss about improvement of test procedure and interpretation.

• 대한조선학회논문집
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• 제56권3호
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• pp.242-250
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• 2019

The speed and power performance of a ship is not only a guarantee issue between the ship owner and the ship-yard, but also is related with the Energy Efficiency Design Index (EEDI) regulation. Recently, International Organization for Standardization (ISO) published the procedure of the measurement and assessment for ship speed and power at sea trial. The results of speed and power performance measured in actual sea condition must inevitably include various uncertainty factors. In this study, the influence for systematic error of shaft power measurement system was examined using the Monte Carlo simulation. It is found that the expanded uncertainty of speed and power performance is approximately ${\pm}1.2%$ at the 95% confidence level(k=2) and most of the uncertainty factor is attributed to shaft torque measurement system.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.396-404
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• 2021

It is important to verify that the contracted speed-power performance of a ship is satisfied in sea trials. International Organization for Standardization (ISO) has published the procedure for measuring and assessing ship speed during sea trials. The results obtained from actual sea conditions inevitably include various uncertainty factors. In this study, double run tests were performed on one container ship to analyze the uncertainty of sea trial on three maximum continuous rating conditions. The uncertainty factors and scale of uncertainty were examined based on the measured raw data during sea trial. The results indicate that the expanded uncertainty for ideal power performance is approximately ±1.4% at 95% confidence level (coverage factor k = 2) and most of the uncertainty factors were because of the shaft power measurement system.

• 대한한의학원전학회지
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• 제24권1호
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• pp.57-71
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• 2011

Although there have been many endeavors aimed at the standardization and globalization of Korean medicine over a long period of time, the access to information on Oriental medical classics has been relatively poor due to the lack of appropriate translation methodology and standard terminology. In order to overcome existing barriers, continuous effort towards precise translation adopting a standard terminology should be maintained. As a part of this procedure, we planned to publish a part of "Classic of difficult issues(難經)" in three sections, and the first two studies have already been published. Based on the methodology and approaches of previous studies, this third study aims to translate parts of "Classic of difficult issues(難經)" into English, beginning with "The Sixteenth Question", and adopting "WHO-IST" terminology. The outcomes of this study are presented as follows: First, based on the result of existing translation studies and the outcome of "WHO-IST", English translation of "Classic of difficult issues(難經)" from "the Sixteenth Question" to "The Twenty-second Question" is offered, hoping to set a model of translation study which can be communicated universally. Second, in order to pave the way for future success in establishing translation studies, it is natural to verify the effectiveness and practicality of standard terminologies including the outcome of "WHO-IST". Continuous translation studies will be required in order to obtain constant feedback and adopt more suitable guidelines during the standardization process. Taking this into consideration, further translation studies of Oriental medical classics including "Classic of difficult issues(難經)" should be continued.

• 한국통신학회논문지
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• 제37B권12호
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• pp.1119-1127
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• 2012

최근 이동통신의 새로운 미래 사업으로 주목받고 있는 M2M 통신의 특성 중 하나는 기존의 통신에 비해 단말의 수가 상대적으로 많다는 점이다. 따라서 다수의 단말로부터 발생하는 제어 신호가 네트워크에 혼잡을 발생시킬 수 있기 때문에 3GPP 표준화단체에서는 이를 해결하고자 여러 단말을 하나의 그룹으로 관리하여 불필요한 시그널링 오버헤드를 줄이는 방법에 대해 표준화를 진행 중에 있다. 본 논문에서는 이동성이 같은 다수의 M2M 단말들을 하나의 그룹으로 관리하는 그룹 기반 이동성 관리 방법에 대해 제안한다. 본 논문에서 제안하는 방법은 이동성이 같은 다수의 M2M 단말을 Mobility Management Entity (MME)가 동적으로 그룹핑하고, 그룹을 대표할 그룹 헤더를 선출하여 그룹 헤더가 그룹을 대표하여 Tracking Area Update (TAU)를 수행하게 함으로써 M2M 단말이 개별적으로 TAU를 수행할 때 발생하는 시그널링 오버헤드를 줄이는 것이다. 제안하는 방법이 기존의 개별적으로 TAU를 수행했을 때보다 최대 80% 정도의 시그널링 오버헤드 감소효과를 보인다.

• 한국항공우주학회지
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• 제40권12호
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• pp.1093-1098
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• 2012

고 신뢰성을 요구하는 우주, 군 등과 같은 응용분야에 집적회로 사용에 대한 필요성이 증가하고 있다. 따라서 상업용(Commercial Off The Shelf) 집적회로부품에 대한 신뢰성 보증 요구조건과 실험규격에 대한 연구가 매우 필요하다. 본 연구에서는 ECSS(European Cooperation for Space Standardization) 품질규격과 MIL-STD-883(집적회로 시험방법)을 기초하여 상업용 집적회로부품의 신뢰성 검증(evaluation)을 위한 스크린(Screening) 실험방법을 검토하였다. 그리고 상업용 부품에 대한 스크린 시험절차와 검사방법을 제안하였다. 또한, 제안한 시험절차와 방법에 맞추어 상업용 Linear Bipolar 집적회로를 평가하였다. 시험결과 상업용 Linear Bipolar 제품이 고 신뢰성 활용을 위한 신뢰성 요구조건을 모두 만족하는 것을 확인하였다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1141-1141
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• 2001

The aim of the study was to evaluate the performance of 3 calibration methods, modified partial least squares (MPLS), local PLS (LOCAL) and artificial neural network (ANN) on the prediction of chemical composition of forages, using a large NIR database. The study used forage samples (n=25,977) from Australia, Europe (Belgium, Germany, Italy and Sweden) and North America (Canada and U.S.A) with information relative to moisture, crude protein and neutral detergent fibre content. The spectra of the samples were collected with 10 different Foss NIR Systems instruments, which were either standardized or not standardized to one master instrument. The spectra were trimmed to a wavelength range between 1100 and 2498 nm. Two data sets, one standardized (IVAL) and the other not standardized (SVAL) were used as independent validation sets, but 10% of both sets were omitted and kept for later expansion of the calibration database. The remaining samples were combined into one database (n=21,696), which was split into 75% calibration (CALBASE) and 25% validation (VALBASE). The chemical components in the 3 validation data sets were predicted with each model derived from CALBASE using the calibration database before and after it was expanded with 10% of the samples from IVAL and SVAL data sets. Calibration performance was evaluated using standard error of prediction corrected for bias (SEP(C)), bias, slope and R2. None of the models appeared to be consistently better across all validation sets. VALBASE was predicted well by all models, with smaller SEP(C) and bias values than for IVAL and SVAL. This was not surprising as VALBASE was selected from the calibration database and it had a sample population similar to CALBASE, whereas IVAL and SVAL were completely independent validation sets. In most cases, Local and ANN models, but not modified PLS, showed considerable improvement in the prediction of IVAL and SVAL after the calibration database had been expanded with the 10% samples of IVAL and SVAL reserved for calibration expansion. The effects of sample processing, instrument standardization and differences in reference procedure were partially confounded in the validation sets, so it was not possible to determine which factors were most important. Further work on the development of large databases must address the problems of standardization of instruments, harmonization and standardization of laboratory procedures and even more importantly, the definition of the database population.