• 항공우주시스템공학회지
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• 제6권4호
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• pp.29-33
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• 2012

This paper is focusing on the difference from experiment result and method through dynamic loaded from impact analysis about inertia measure unit of high speed projectile. At Inertia measure unit dynamic load is applied when the high speed projectile is operated by impact to inside. it is necessary to design inertia measure unit enduring from external effect with operating environment. Investigation of material deformation with high strain speed is performed for military purpose, and still concerned to many scientist. From this study, this paper will prove of impact analysis result through comparing with experiment result and method when applied dynamic load.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.547-550
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• 2000

The steel pipe for fluid catalytic cracking(FCC) unit. petroleum refinery, is lined with refractory to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis of FCC unit. Because 1-D pipe element or 3-D shell element are usually used in commercial codes of stress analysis to evaluate the structural soundness, the equivalent elastic modulus considering steel and refractory should be applied. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the stress analysis is carried out with the part of FCC unit.

• International Journal of Reliability and Applications
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• 제8권1호
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• pp.67-82
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• 2007

This paper deals with the effectiveness analysis of an engineering system, which has two units of different strengths in parallel and one unit as a cold standby unit. Failure times for all the units have negative exponential distribution whereas their repair times have general distribution. Single server caters the need for the system. The effectiveness analysis of the system is done by using regenerative point technique. The different measures of effectiveness such as mean sojourn time, mean time to system failure, availability, busy period, etc, are derived. Cost factors also taken into consideration.

• 한국환경보건학회지
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• 제35권3호
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• pp.191-200
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• 2009

We investigated a trait of odor and the relationship between odor unit and odorous compounds using multiple regression analysis based on data compiled from Sihwa (SIC), Banwol (BIC), Banwol plating (BPIC) and Poseung industrial complex (PIC). These areas are odor control areas in Gyeonggi province. It was revealed that $NH_3$ and styrene concentrations in SIC and BPIC were relatively higher and $H_2S$ concentration especially in mc was more than five times higher than other areas. As a result of regression analysis using SAS, intensity of odor unit was highly related to concentrations of $H_2S$, TMA, styrene and n-valeraldehyde in SIC, $H_2S$, acetaldehyde, and butyraldehyde in BPIC and $NH_3$ in BIC.

• 한국비블리아학회지
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• 제33권4호
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• pp.27-47
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• 2022

이 연구의 목적은 교육과정과 연계할 수 있는 교과 단원목록 시스템의 개발에 있다. 연구방법은 먼저 중학교 교육과정과 과학과 전 학년의 교과서 분석을 통해 단원 주제어를 추출하였다. 이를 바탕으로 교과의 단원주제와 관련된 도서를 연결하여 단원 도서목록, 단원주제어를 색인어로 정리한 색인어목록, 그리고 단원주제와 연계된 학년 및 학교급 연계목록을 하부 시스템으로 하는 단원목록 시스템을 설계하였으며, Notion 프로그램을 활용하여 중학교 과학 1단원을 표본으로 웹상에서 단원목록 시스템을 구현하였다. 시스템 평가를 위해 학생들을 대상으로 실험 및 설문 조사를 하였으며, 시스템 만족도 및 추후 활용 의향 등에서 매우 긍정적인 결과를 보였다. 한편 이 연구는 중학교 과학과를 대상으로 한정하였지만 전체 학년 및 교과로 확대 적용할 것을 제안하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.204-205
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• 2020

Construction Standard Unit Price is the unit price calculated based on the market price for work items in construction projects that have already been conducted. It is used as basic data for calculating the budget price of public construction projects. In the Construction Standard Unit Price Book implemented in the second half of 2020, there are 1,810 types of unit prices. Since 2017, 100-150 construction standard unit prices have been revised semiannually (on January 1 and July 1 of each year) through Construction Site Surveys. Other work items have been set based on the rate of inflation during the corresponding period. Later in 2020, this procedure was changed, with on-site survey period extended to one year to strengthen the construction standard unit price investigation. The revisions previous announced during the second half of the year were changed only to reflect the price inflation rates. With such changes in the revisions to construction standard unit prices, one important issue that was raised: The timing of announcing the revisions during the second half of the year (reflecting the price inflation rates). The market unit wage, which is the unit price standard of labor cost that takes up a large part of the construction cost, is announced in January and September. The figures announced in September is reflected on the construction standard unit price four months later in January, but the market unit wage announced in January is reflected only six months after in July, which causes a timing issue. As such, the current study analyzed problems rising from the changed timing of the announcements of the construction standard unit price during the second half of the year, in addition to analyzing their impact on public construction projects.

• 한국환경과학회지
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• 제24권4호
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• pp.393-401
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• 2015

Rainfall-runoff model of Jeju Oedo Stream was used to compute the optimal unit hydrograph by HEC-HMS model that reflecting on watershed characteristics. Each rainfall event was comparatively analyzed with the actual flow measurement using Clark, Snyder and SCS synthetic methods for derived unit hydrograph. Subsequently, the null hypothesis was established as p-value for peak flow and peak time of each unit hydrograph by one-way ANOVA(Analysis of variance) was larger than significance level of 0.05. There was no significant difference in peak flow and peak time between different methods of unit hydrograph. As a result of comparing error rate with actual flow measurement data, Clark synthetic unit graph best reflected in Oedo Stream as compared to other methods, and error rate of Clark unit hydrograph was 0.02~1.93% and error rate at peak time was 0~2.74%.

• 대한가정학회지
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• 제50권6호
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• pp.43-54
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• 2012

The purpose of this study was to identify the factor structure of self-efficacy, clothing behaviors, contents application of the unit 'preparing and managing clothes' and the effects of self-efficacy on clothing behavior and contents application of the unit 'preparing and managing clothes'. Questionnaires were administered to 201 girl students in middle school, living in the Daegu area. Frequency, descriptive statistics, factor analysis, reliability analysis, and multiple regression were used for data analysis. The findings are as follows. Self-efficacy was composed of five factors, namely interpersonal skills, task performance skills, anxiety, planned performance, and challenging action. Clothing behavior was composed of five factors, namely pleasure, coordinated clothes, uniform preference, learning behavior, and fashion oriented. Contents application of the unit 'preparing and managing clothes' was composed of two factors, namely usefulness of lectures in general, and usefulness of Hanbok lecture. The effects of clothing behavior and contents application of the unit 'preparing and managing clothes' on each of the self-efficacy variables, like interpersonal skills, task performance skills, anxiety, planned performance, and challenging action were explained by factors such as pleasure, coordinated clothes, uniform preference, learning behavior and fashion oriented, and usefulness of lectures in general and usefulness of Hanbok lecture.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권2호
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• pp.288-300
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• 2015

Since the first jack-up was built, jackups have become the most popular type of mobile offshore drilling unit (MODU) for offshore exploration and development purposes in shallow water. The most pivotal component of the jack-up unit is the leg, which can directly affect the global performance of the unit. In this paper, an investigation into extending the length of the jack up leg is carried out in order to study the enhancement of the rig capability to drill in deeper water approaching the range of the Semisubmersible Drilling Unit (SSDU) (300-1000ft). A study of the performance of a deep-water jack-up unit is performed with different leg lengths. Typical leg scantling dimensions and identical external loads are assigned, and then a detailed Finite Element Analysis (FEA) model is created in order to simulate the jack-up leg unit's structural behavior. A Multi-point Constraint (MPC) element together with the spring element is used to deal with the boundary conditions. Finally, a comparative analysis for five leg lengths is carried out to illustrate their performance, including the ultimate static strength, and weight.

• Nuclear Engineering and Technology
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• 제53권2호
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• pp.386-392
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• 2021

MACCS (MELCOR Accident Consequence Code System), WinMACCS, and MelMACCS now facilitate a multi-unit consequence analysis. MACCS evaluates the consequences of an atmospheric release of radioactive gases and aerosols into the atmosphere and is most commonly used to perform probabilistic safety assessments (PSAs) and related consequence analyses for nuclear power plants (NPPs). WinMACCS is a user-friendly preprocessor for MACCS. MelMACCS extracts source-term information from a MELCOR plot file. The current development can combine an arbitrary number of source terms, representing simultaneous releases from a multi-unit facility, into a single consequence analysis. The development supports different release signatures, fission product inventories, and accident initiation times for each unit. The treatment is completely general except that the model is currently limited to collocated units. A major practical consideration for performing a multi-unit PSA is that a comprehensive treatment for more than two units may involve an intractable number of combinations of source terms. This paper proposes and evaluates an approach for reducing the number of calculations to be tractable, even for sites with eight or ten units. The approximation error introduced by the approach is acceptable and is considerably less than other errors and uncertainties inherent in a Level 3 PSA.