• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.337-348
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• 2023

The optimization of reinforced concrete (RC) cantilever retaining walls is a complex problem and requires the use of advanced techniques like metaheuristic algorithms. For this purpose, an optimization model must first be developed, which involves mathematical complications, multidisciplinary knowledge, and programming skills. This task has proven to be too arduous and has halted the mainstream acceptance of optimization. Therefore, it is necessary to unravel the complications of optimization into an easily applicable form. Currently, the most commonly used method for designing retaining walls is by following the proportioning limits provided by the ACI handbook. However, these limits, derived manually, are not verified by any optimization technique. There is a need to validate or modify these limits, using optimization algorithms to consider them as optimal limits. Therefore, this study aims to propose updated proportioning limits for the economical design of a RC cantilever retaining wall through a comprehensive parametric investigation using the genetic algorithm (GA). Multiple simulations are run to examine various design parameters, and trends are drawn to determine effective ranges. The optimal limits are derived for 5 geometric and 3 reinforcement variables and validated by comparison with their predecessor, ACI's preliminary proportioning limits. The results indicate close proximity between the optimized and code-provided ranges; however, the use of optimal limits can lead to additional cost optimization. Modifications to achieve further optimization are also discussed. Besides the geometric variables, other design parameters not covered by the ACI building code, like reinforcement ratios, bar diameters, and material strengths, and their effects on cost optimization, are also discussed. The findings of this investigation can be used by experienced engineers to refine their designs, without delving into the complexities of optimization.

• Journal of Aerospace System Engineering
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• v.17 no.2
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• pp.1-8
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• 2023

Power transmission shafts in rotary wing aircraft use a hollow shaft to reduce weight. We can apply linear elastic fracture mechanics to predict crack propagation behavior. This paper predicted crack growth life of a hollow shaft with a circumferential through-type crack by finite element analysis. A 2D finite element model was created by applying a torsion and forming elements considering cracks. We defined the initial crack length and performed the finite element analysis by increasing the crack length to derive stress intensity factor at crack tips. We defined the length just prior to the stress intensity factor exceeding the fracture toughness as the crack limit length. We calculated the crack limit length using a handbook and numerically integrated the crack growth rate equation to derive growth life of each crack. The growth life of each crack was compared to verify the proposed finite element analysis method.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.3
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• pp.134-147
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• 2019

The purpose of this study was to analyze the functional unit system of NCS landscape field for correction and supplementation of NCS landscape field and the contents of the four-year college landscape course subject. First, 24 unconsolidated four-year universities were selected, and FGI was conducted and verified for 816 courses in 24 universities. The results of the study are summarized as follows, with three sections three, nine divisions and 65 sub-category. First, landscape design subjects accounted for 40.0% of the subjects organized by four-year universities. In addition, the ratio of 12.9% for ecological landscape, 11.3% for landscape construction, 10.2% for others, 10.0% for landscape information, 6.6% for landscape culture and 3.7% for landscape management was surveyed. Balanced and efficient modification and reinforcement of NCS is required in the future. Second, 10(18.9%) units with matching NCS performance criteria and educational objectives were found to be capable of different units(18.9%), 15(28.3%), and 37subjects with inconsistent NCS unit capability (56.9%). Third, looking at the criteria for the reference of each unit of capability presented by the NCS, it is deemed that one unit of capability should be organized separately to improve the practical ability, since it includes the contents of basic knowledge learning. Fourth, the objectives pursued on the basis of the contents of the NCS capability unit and four-year college curriculum were developed by focusing on the development of unit capabilities in the field of landscape construction and landscape management compared to the field of landscape design. It has been shown that a balance is needed for future development. This study is intended to put forward further research that re-examine specific curriculum assessment criteria that have not been classified in the course of classifications based on the curriculum handbook, which excludes interferences from each school.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.1
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• pp.55-64
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• 2016

Objectives : In 2007, a survey of how Kampo was regarded in Japanese clinical practice guidelines (CPGs) was first conducted by the Special Committee for Evidence Based Medicine (EBM), namely the Japan Society for Oriental Medicine (JSOM). A manual for CPG development was also published in 2007 by the Japan Council for Quality Health Care, and the revised edition came out in 2014. The purpose this study is to review the current state in CPGs applied to Kampo after 2007, while focusing on how Kampo products being regarded evidence based branch of medicine by CPG developers. Methods : Sources include the Kampo CPGs website of Japan Society for Oriental Medicine (JSOM) and MINDS (Medical Information Network Distribution Service) website of Japan Council for Quality Health Care. Results : Among the 784 CPGs existing by the end of 2015, 91 CPGs were considered containing descriptions of Kampo. Furthermore, 28 type A Kampo CPG (KCPG) which had quality of evidence and strength of recommendation with references were found. Also, most of type A KCPGs relied on the MINDS Handbook for Clinical Practice Guideline Development that was published in 2007. Conclusions : The number of KCPGs are increasing yearly. However, there is still not much Kampo evidence found in CPGs in Japan. Overall, it could be said that we need to not only make evidence vertically but preach it horizontally well.

• Korean Journal of Child Education & Care
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• v.18 no.3
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• pp.159-178
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• 2018

Objective: The purpose of this study was to understand the characteristics of dietary education in South Korea and Japan, and find directions for dietary education by comparing the contents of the two countries' dietary education in their national child-care curriculums and evaluations. Methods: To this end, a qualitative content analysis was conducted on the guidebooks for the Standard Child-care Curriculum and the Accreditation Index for Child-care Center in the case of South Korea, and the handbook for the Child-care Guideline and the Third Party Evaluation in the case of Japan. Results: The findings of this study were as follows: First, South Korea showed differences in the focus of child-care curriculums and evaluations. The contents about proper eating such as nutrition and table manners comprised a high portion of the curriculums, whereas the contents about cleanness and hygiene accounted for a high portion of the evaluations. In the case of Japan, its national child-care curriculums and evaluations consistently emphasized contents related to enjoying eating oneself, and suggested various methods for this. Second, in terms of the two countries' approaches to dietary education, South Korea focused on food-related knowledge, whereas Japan mainly created the contents of dietary education based on daily experiences. Conclusion/Implications: The above results suggest a direction to improve the currently publicized dietary guidance problem and a need for consistent the national child care curriculum and evaluation indicators in South Korea to emphasize the importance of joyful eating.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.3
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• pp.107-120
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• 2005

In Korea, MOCT and KOWACO published a standard for lineament map drawings, "The Handbook for the Drawing and Management of Hydrogeologic Map" in 2003. According to this guideline, hydrogeologic and related thematic maps should include characteristics of groundwater quality and quantity. These maps are generally drawn with ArcView GIS 3.x software. The activities of well notation on groundwater level map and Stiff diagram drawings on groundwater quality map require a great deal of efforts because hundreds or thousands of well data, water level data and hydrogeochemical data are produced through many kinds of investigations. As well, lineament density map is very important to survey and explore groundwater in a deep aquifer. In this study we developed some modules for well notation, Stiff diagram drawings, and lineament density value calculation with Avenue$^{TM}$ script and it was revealed that they can be very useful and easy for drawing groundwater thematic maps.

• Journal of Korea Water Resources Association
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• v.42 no.8
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• pp.643-657
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• 2009

The major reason to construct large dams is to store surplus water during rainy seasons and utilize it for water supply in dry seasons. Reservoir storage has to meet a pre-defined target to satisfy water demands and cope with a dry season when the availability of water resources are limited temporally as well as spatially. In this study, a Hedging rule that reduces total reservoir outflow as drought starts is applied to alleviate severe water shortages. Five stages for reducing outflow based on the current reservoir storage are proposed as the Hedging rule. The objective function is to minimize the total discrepancies between the target and actual reservoir storage, water supply and demand, and required minimum river discharge and actual river flow. Mixed Integer Linear Programming (MILP) is used to develop a multi-reservoir operation system with the Hedging rule. The developed system is applied for the Han River basin that includes four multi-purpose dams and one water supplying reservoir. One of the fours dams is primarily for power generation. Ten-day-based runoff from subbasins and water demand in 2003 and water supply plan to water users from the reservoirs are used from "Long Term Comprehensive Plan for Water Resources in Korea" and "Practical Handbook of Dam Operation in Korea", respectively. The model was optimized by GAMS/CPLEX which is LP/MIP solver using a branch-and-cut algorithm. As results, 99.99% of municipal demand, 99.91% of agricultural demand and 100.00% of minimum river discharge were satisfied and, at the same time, dam storage compared to the storage efficiency increased 10.04% which is a real operation data in 2003.

• Journal of the Korean Society of School Health
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• v.17 no.2
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• pp.127-150
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• 2004

Objectives: The purpose of this study is to provide a basic structure for the establishment of the direction of school health programs, an overview of the historical changes of school health programs and their results, and a conceptual framework on school health programs. Methods: The data analysis has been done using a statistical almanac, relevant laws and regulations, operation handbook of the program, theses, reports, records of public hearings, and other reports as a technical research primarily based on evidence. The methodology of this research classifies the development and growth transition of school health programs during a historical period through the investigation of regulations, organization, manpower, and its program via its development process and to provide a basic tool to design a solid school health policy. Results: A The growth and development of school health programs The development of school health programs was classified into three different periods including the forthcoming period (1945~1967), the completion period (1967~1993), and the actualization period based on the establishment of legislation for School Health Law, other relevant legislation, and the contents of school health programs (1993~present). B. Policy direction of school health programs School health programs have reestablished their goals and range based on basic direction, and developed the W1it model of information structure for school health program management and its basic structure. Finally, the stepwise support system through the building of the school health support center is recommended. (1) The basic direction of school health programs has proposed 7 basic goals to reestablish the policy direction of health improvement based on total health. (2) The W1it model of information system and the school health information system for school health program management has been developed to utilize positive management. (3) School health policy through the study of the health laws and systems has been developed. The necessity of school health support center for the policy support, functional support and operation support has also been proposed. Conclusions: It is necessary to build a school health support center that consists of health professionals in charge of policy support, functional support, and program support of school health programs in order to realize and develop new policy.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.6
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• pp.1094-1103
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• 2001

According to standard procedures as defined in the users handbook for sea level data processes, I was compared to Topex/Poseidon sea level data from the first 350days of mission and Tide Gauge sea level data from the Amsterdam- Crozet- Kerguelen region in the South Indian Ocean. The comparison improves significantly when many factors for the corrections were removed, then only the aliased oceanic tidal energy is removed by oceanic tide model(11) in this period. Making the corrections and smoothing the sea level data ()ver 60km along-track segments and the Tide Gauge sea level data for the time series results in the digital correlation and RMS difference between the two data of c=-0.12 and rms= 11.4cm, c=0.55 and rms=5.38cm, c=0.83 and rms=2.83cm, and c=0.24 and rms=6.72 for the Amsterdam, Crozet and Kerguelenplateau, and Kerguelen coast, respectively. It was also found that the Kerguelen plateau has a comparisons due to propagating signals(the baroclinic Rossby wave with velocity of -3.9 ~-4.2cm/sec, period of 167days and amplitude of 10cm) that introduce temporal lags(${\gamma}$: 10~30days) between the altimeter and tide gauge time series. The conclusion is that on timescales longer than about 10days the RMS sea level errors are less than or of the order of several centimeters and are mainly due to the effects of currents rather than the effects of stories(water temperature, density) and winds.

• Journal of Engineering Education Research
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• v.9 no.2
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• pp.34-51
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• 2006

In knowledge based society of 21c, engineers require not only their own speciality but also engineering basic competency such as creative thinking, the ability of working together, the ability of communication. Engineering colleges responsible for educating engineers consider developing curriculum including Engineering Basic Competency which is reflecting the needs of the times. By utilizing the accreditation programs of engineering education, UK-SPEC of UK Engineering Council, EA(Engineering Australia) standards/handbook of the Institute of Engineers Australia, O*NET of U.S. Occupational Network, this study generates core elements of engineering basic competency to prove the capability of engineering basic competency required to desired engineers. Core constituents derived from the study were categorized into 3 major areas of the basic engineering literacy in Humanities and Social Sciences(HSS), the ability of Creativity Engineering Design, Career development and each category and constituents were surveyed and checked by engineers in the field to deduce engineering basic competency that should be educated in the engineering college.