• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.1-11
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• 2000

In optimum design of packaging container for bulk materials, minimum board area, compression performance and distribution efficiency must be considered. In this study, mathematical models for minimum board area (RMA), compression strength (CS) and maximum compression strength per unit board area (MCSA) of container as algorithm for optimum design of packaging conatiner for bulk materials were developed as follows : RMA=f(V,D), ${\alpha}_{RMA}=f(V,D)$, MCSA=f(V,D), and ${\alpha}_{MCSA}=f(V,D)$. In order to develop these models, compression test according to various dimensions of container and response surface analysis for minimum board area, compression strength, and maximum compression strength per unit board area of container were carried out. In developed models, volume and depth of container were principal independent variables. Through the verified results for these models, optimum design of packaging container on the design conditions and limit conditions was possible. These models might be used in developing optimum design software of packaging container for bulk materials.

• Journal of Advanced Navigation Technology
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• v.21 no.5
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• pp.508-513
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• 2017

Maintainability in engineering terms means ease of maintenance / management of the product. Aircraft automatic test equipment (ATE) is heavily influenced by the design changes of the unit under test(UUT) since the test procedure is developed according to the function / performance characteristics of the UUT. Moreover, if the integrated ATE is an environment that checks more than one UUT, it is not easy to maintain the ATE for the UUT design changes. Developers should be able to flexibly cope with the change of development staff by selecting an easy and clear development method to improve the maintainability of ATE. It is also necessary to limit the area affected by the UUT design change to a specific range to minimize the area to be modified. In this paper, we propose ATE development method which focuses on maintenance improvement based on the aircraft ATE development process.

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.4
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• pp.27-43
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• 1990

This study aimed at developing a generalized model on the estimation of the long - term run - off volume for practical purpose. During the research period of last 3 years( 1986-1988), 3 types of estimation model on the long - term run - off volume(Effective rainfall model, unit hydrograph model and barne's model for dry season) had been developed by the author. In this study, through regressional analysis between determinant factors (bi of effective rainfall model, ai of unit hydrograph model and Wi of barne's model) and catchment characteris- tics(catchment area, distance round the catchment area, massing degree coefficient, river - exte- nsion, river - slope, river - density, infiltration of Watershed) of 11 test case areas by multiple regressional method, a new methodology on the derivation of determinant factors from catchment characteristics in the watershed areas having no hydrological station was developed. Therefore, in the resulting step, estimation equations on run - off volume for practical purpose of which input facor is only rainfall were developed. In the next stage, the derived equations were applied on the Kang - and Namgye - river catchment areas for checking of their goodness. The test results were as follows ; 1. In Kang - river area, average relative estimation errors of 72 hydrographs and of continuous daily run - off volume for 245 days( 1/5/1982 - 31/12) were calculated as 6.09%, 9.58% respectively. 2. In Namgye - river area, average relative estimation errors of 65 hydrographs and of conti- nuous daily run - off volume for 2fl days(5/4/1980-31/12) were 5.68%, 10.5% respectively. In both cases, relative estimation error was averaged as 7.96%, and so, the methodology in this study might be hetter organized than Kaziyama's formula when comparing with the relative error of the latter, 24~54%. However, two case studies cannot be the base materials enough for the full generalization of the model. So, in the future studies, many test case studies of this model should he carries out in the various catchment areas for making its generalization.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.1-15
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• 2013

The purpose of this study is to quantitatively analyze the corresponding residents' benefit to get in the future from the district unit plan of the settlement zone by Cheongju local government. The target districts were selected as Gumdeong-gol district, Juseong district, and Shinmok-gol district, and Hyeonam district which had recently set their district unit plans. Specific targets to be analyzed were some infrastructure including roads, parking lots, parks and others. Using the analysis methods of the Logit model and non-parametric test approach, this study estimated to the average amounts to be willingly paid(WTP) by the residents in targeting settlement zones and tested the reliability of the average amounts of WTP. The results of analysis were as follows. First, it was found that the WTPs for infrastructure under 1st influence area in target districts were estimated as 5,233won for road, 2,826won for parking lot, and 3,705won for park respectively. For the WTPs for infrastructure under 1nd area were estimated as 4,910 won for road, 2,242won for parking lot, and 3,620won for park respectively. Second, as the result of calculating the non-parametric WTP which built the 95% confidence interval, it was found that the all WTPs except the WTP for parking lot were fell into the 95% confidence interval. Third, as the result of calculating yearly total sum of benefits that the residents would get from the 1st influence area and the 2nd influence area, it was found that Gumdeong-gol district were expected to get 62,376,472won-amounted benefits, and Juseong district, and Shinmok-gol district, and Hyeonam district would get 35,0778,016won, 26,886,560won, and 22,252,032won respectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.853-860
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• 2003

Relationship between axial strain and volumetric strain of Light-Weighted Foam Soil (LWFS) are investigated. LWFS is composed of the dredged soil from offshore, cement and foam to reduce the unit weight and also increase compressive strength. For this purpose. the triaxial compression tests are carried out on the prepared specimens of LWFS with various conditions such as initial water contents, cement contents, and curing stresses, The test results of LWFS Indicated that the axial strain - volumetric strain relationship is almost linearity with increase cement contents and the unit weight but the relationship is non-linearity with decrease cement contents and the unit weight. In this study, it is found that assuming no change of cross section area of LWFS, axial strain occurring the poisson's ratio of zero, that the axial strain same to volumetric strain, steeply increases with decrease the unit weight, initial water content, and cement contents.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.655-660
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• 2001

The performance test of a centrifugal compressor for APU(Auxiliary Power Unit) which is developed by the collaborative research of KARI and Samsung TechWin has been conducted. The investigated compressor consists of a curved inlet, a centrifugal impeller, a channel diffuser and a plenum chamber. The experiments were carried out in an open-loop centrifugal compressor test rig driven by a turbine. For three different diffusers, overall performance data were obtained at 80%, 90% and 97% of design speed. For the initially designed wedge-type diffuser, test results showed that the compressor was operated at a higher mass flow rate than the design requirement. By reducing the diffuser throat area, the compressor operating range was shifted to lower mass flow rate range. The test result of redesigned wedge-type diffuser showed high pressure loss. To reduce the diffuser loss, diffuser inlet radius was increased and airfoil-type of diffuser was adopted. This airfoil-type diffuser showed reasonal results in terms of design requirement.

• Journal of the Korea Concrete Institute
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• v.12 no.3
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• pp.3-10
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• 2000

In this study, we compared a plain mortar with the CAS-system shrinkage compensation mortar for Ondol that is Korean traditional heating system. The Ondol mortar is necessary to have properties as non-crack, fine flatness and stability for thermal changes. especially, mortar'crack prevention is to be most important property in Ondol mortar. To develope the stable material on the crack-prevention, we used to calcium-sulfo-aluminate(CSA)system in shrinkage compensation mortar. And so, we confirmed the effects of calcium-sulfo-aluminate(CSA) system for mortar's physical properties such as setting time, compressive strength and expansion ratio for crack prevention. The initial and final setting time of the CSA mortar is faster than plain mortar about 2hours. And, Compressive strength increased about 20% that plain mortar. The crack length per unit area, plain mortar is 0.426∼0.481m/m2. The Results of apartment construction field test, the shrinkage compensation mortar is excellent about the crack-reduce effect.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.1
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• pp.197-205
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• 1991

A methodology of constructions a mathematical cost model for an activity constituting ship hull assembly process is proposed. The relationship between number of workers and processing time required for an activity can be formulated using an work study method, then manhours and shop floor area-hours required are calculated accordingly. The costs for unit manhour and unit shop floor area-hour respectively are calculated by distributing the overall annual cost of the company to the overall production resources consummed during the year. A general procedure of implementing the methodology has been demonstrated through a test on an exampled activity drawn from a real process.

• Journal of Digital Convergence
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• v.20 no.1
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• pp.379-389
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• 2022

This study was aimed to identify importance and satisfaction of intensive care unit health care providers for Intensive Care Unit Clinical Nurse Expert (ICU CNE) roles. A questionnaire survey was performed with 138 intensive care unit health care providers between May 3 to 29, 2021. Data were analyzed using descriptive statistics. t-test and Importance-Performance Analysis (IPA). There were statistically significant differences in importance(t=2.33, p=.024) and satisfaction(t=5.43, p<.001) between physicians and nurses. The importance and satisfaction of intensive care unit health care providers were ranked in the order of advanced clinical practice, professional activity, coordination and cooperation, education and counseling and research. In the 'concentrate' area, it was found that 'Professional activity' and 'Education' should be improved. A strategy is needed to strengthen the expertise of ICU CNE and to enhance the competency in areas that need improvement.

• International Journal of Advanced Culture Technology
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• v.6 no.3
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• pp.173-177
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• 2018

Masks are generated by adding different fonts of learning data characters in pixel unit, and pixel values belonging to each of the masks are divided into 3 groups. Using the directional expansion operators, we expand the text area of the test data character into 4 diagonal directions in order to create the boundary areas to distinguish it from the background area. A mask with a minimum average discordance is selected as the final recognition result by calculating the degree of discordance between the expanded test data and the masks. Image comparison using directional expansion operations more accurately recognizes test data through 4 subdivided recognition processes. It is also possible to expand the ranges of 3 groups of pixel values of masks more evenly such that new fonts can easily be added to the given learning data.