• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.8
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• pp.781-788
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• 2013

Predicting the engine component temperature is a basic step to conduct structural safety evaluation in medium-speed diesel engine design. Recent trends such as increasing power density and performance necessitate more effective thermal management of the engine for achieving the desired durability and reliability. In addition, the local temperatures of several engine components must be maintained in the proper range to avoid problems such as low- or high-temperature corrosion. Therefore, it is very important to predict the temperature distribution of each engine part accurately in the design stage. In this study, the temperature of an engine component is calculated by using steady-state conjugate heat transfer analysis. A proper approach to determine the thermal load distribution on the thermal boundary area is suggested by using 1D engine system analysis, 3D transient CFD results, and previous experimental data from another developed engine model. A Hyundai HiMSEN engine having 250-mm bore size was chosen to validate the analysis procedure. The predicted results showed a reasonable agreement with experimental results.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.422-434
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• 2020

This study aims to analyze the types of college admission that should be strengthened or reflected in universities and to suggest the direction of entrance examination by identifying the actual implementation of the literature-science integrated 2015 revised national curriculum. In order to do so, in-depth interviews on the current state were executed to five curriculum experts. As a result of the interview, it was found that the introduction and adoption of clear admission types look into the inner side of high school life are necessary. Also, it is required to establish specific criteria for student selection expand in-depth interviews related to learning activities in high school, strengthen evaluation competence of admission staffs and recruit more evaluation personnel. In addition, in order to revitalize the 2015 revised curriculum, it is necessary to evaluate how many subjects, especially in career-related subjects, students have taken in order to expand the school record-focused system. For this, it is required to extract evaluation elements and criteria of universities that can grasp continuous and active role performance, and to design a typical design that can objectively judge them. This study can contribute to the settlement of the selection process that can revitalize public education. And it is expected that the selection of the talents desired by the university will be used as a possible basic data.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.7 s.337
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• pp.27-34
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• 2005

Iterative detection (ID) has proven to be a near-optimal solution for concatenated Finite State Machines (FSMs) with interleavers over an additive white Gaussian noise (AWGN) channel. When perfect channel state information (CSI) is not available at the receiver, an adaptive ID (AID) scheme is required to deal with the unknown, and possibly time-varying parameters. The basic building block for ID or AID is the soft-input soft-output (SISO) or adaptive SISO (A-SISO) module. In this paper, Reduced State SISO (RS-SISO) algorithms have been applied for complexity reduction of the A-SISO module. We show that serially concatenated CPM (SCCPM) with AID has turbo-like performance over fading ISI channels and also RS-A-SISO systems have large iteration gains. Various design options for RS-A-SISO algorithms are evaluated. Recently developed density evolution technique is used to analyze RS-A-SISO algorithms. We show that density evolution technique that is usually used for AWGN systems is also a good analysis tool for RS-A-SISO systems over frequency-selective fading channels.

• Journal of the Korea Society of Computer and Information
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• v.25 no.3
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• pp.243-250
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• 2020

In this paper, we propose an effective software education scheme for universities. The key idea of this software education scheme is to analyze software curriculum of QS world university rankings Top 10, SW-oriented university, and regional main national university. And based on the results, we propose five improvements for the effective SW education method of universities. The first is to enhance the adaptability of the industry by developing courses based on the SW developer's job analysis in the curriculum development process. Second, it is necessary to strengthen the curriculum of the 4th industrial revolution core technologies(cloud computing, big data, virtual/augmented reality, Internet of things, etc.) and integrate them with various fields such as medical, bio, sensor, human, and cognitive science. Third, programming language education should be included in software convergence course after basic syntax education to implement projects in various fields. In addition, the curriculum for developing system programming developers and back-end developers should be strengthened rather than application program developers. Fourth, it offers opportunities to participate in industrial projects by reinforcing courses such as capstone design and comprehensive design, which enables product-based self-directed learning. Fifth, it is necessary to develop university-specific curriculum based on local industry by reinforcing internship or industry-academic program that can acquire skills in local industry field.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.3
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• pp.243-250
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• 2009

The expression of signal to noise ratio (SNR) is derived for the individual echo sounder and for the general specifications of commercial echo sounder. The SNR is depicted by several factors on transmitting and receiving, sound propagation, scattering by fishes, and mainly self ship noise. The detection ranges of echo sounders in depth and breadth are derived by finding the border of an acceptable SNR. The detection ranges are computed for the echo sounders of individual and general specifications. Generally, the detection range is lager for low frequencies. Increasing an electrical power and a diameter of transducer is not as effective for high frequencies as for low frequencies to increase the detection range. The theoretical results of the detection range can be applied to design low electrical power echo sounder for coastal use, to select an appropriate echo sounder, to know the capability of a sounder, and to interpret echograms. A method for evaluating and designing low electrical power echo sounder is developed. A universal diagram for the basic design of the low electrical power echo sounder where SNR is plotted against frequency is developed. An appropriate frequency, transducer diameter, and beam width are easily determined by using the diagram.

• Korean Journal of Optics and Photonics
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• v.13 no.4
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• pp.363-369
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• 2002

We have designed conductive transparent filters using a low-emissivity coating such as [dielectric|Ag|dielectric] for display applications. The design is the repetition of [$TiO_{2}$|Ti|Ag |$TiO_{2}$] to increase the transmittance in the visible and decrease the transmittance in the near IR. The conductive transparent filters are deposited by a radio frequency(RF) magnetron sputtering system. The optical, structural and electrical properties of the filters were investigated and the optical spectra are compared with simulated spectra. The thickness of the deposited Ag films is above 13 ㎚ to increase the conductivity and that of $TiO_{2}$ films is 24 ㎚ to increase the transmittance in the visible range. Ti blockers are employed to prevent the Ag films from being oxidized by an oxygen gas during the reactive sputtering process. Also, it is shown that the thicker Ti film is necessary as the period increases. Finally, a filter with repetition of the basic structure three times shows the better cut-off near infrared(NIR) and the sheet resistance as low as 2Ω/□ which is enough to shield an unnecessary electromagnetic waves for a display panel.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.2
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• pp.59-71
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• 2006

Due to the rapid process of industrialization the cities of Korea confront changes of climate, destructions of the habitate and decrease of the green. Recently Seoul and other local governments have implemented policies and projects to improve the environmental surroundings. In reality, however, those policies and projects face difficulties in the course of implementation. The fact that there are no concrete regulations and specific legal procedures turns out to be one of the main difficulties. The aim of this study is to present specific plans and methods of wall-planting and to provide basic guidelines for the future direction of wall-planting and offer ideas of facilitating wall-planting. This study is based on questionnaires from specialists of landscape architecture through individual interviews and/or e-mails. The questionnaire is consisted of following 4 sections. 1. Show the experts current regulations and/or legal procedures and ask them improvements and suggestions. 2. Ask them choose matters of the highest priority by using Ricardo's diagram method. 3. Ask them to make a graded list in terms of the location and method of wall-planting. 4. Study the maketability of the wall-planting products currently in circulation. The city of Seoul and the Ministry of Environment recommend that trellis and/or planting inducement structures be installed on the building wall by regulation. The specialists responded to the questionnaire advocate that green wall without trellis should be allowed as green zone. Therefore regulations concerning the wall-planting should be determined specifically according to the characteristics of individual plants and walls. It has been urged that legal aid and social support must be reinforced to establish rules dealing with wall-planting. The respondents also point out that significant cutting down of the tax is far more effective in accelerating the wall-green instead of administrative support. The highest priority in terms of planting has been given to sound-proof wall, retaining wall and building wall. Concerning the maketability of the wall-planting products, panel products are recommended for early-planting and building planting. It has been suggested that the research and study of new materials and species be done in advance.

• Science of Emotion and Sensibility
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• v.13 no.2
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• pp.381-390
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• 2010

The automotive seat comfort evaluation was to begin a key aspect in seat design. It depended largely on the basic mechanical aspect such as geometric parameters of seat, choice of suspension system and cushion material used. Until recently, seat comfort evaluation advanced to evaluate subjective sensitivity of human. The external literatures showed in the last decade, there have been very few attempts to establish and document automotive seat comfort evaluation. In 2006 Smith, D. proposed the statistically reliable tool in giving a numeric rating for set comfort and the tool was used in the many country. On the other hands, we, in Korea, had not the reliable tool for the automotive seat comfort evaluation. So that, we studied to develope the questionnaire for seat comfort evaluation based on Smith, D.(2006) and some studies. As a result, we developed 36 contents for the automotive seat comfort evaluation with the help of professional in Korean automotive industry. Here, 36 contents were identified as the dimensions that represent the human sensitivity and psychological feeling on comfortable seat. Also, we derived the priorities for the 36 contents by using analytic hierarchy process (AHP), based on the judgments of 30 experts and drivers. This study will help the designers and developers clarify the conceptual and abstract aspect of the design evaluation by proposing a more systematic and process-oriented method.

• The Journal of the Korea Contents Association
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• v.8 no.3
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• pp.86-96
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• 2008

General development basis of letter system is recognized by formative value in terms of its function and structure. principle of clustered writing is the most significant feature of Hangeul typography as considered that it is based on function and formativeness. Thus, not only by changes with its form but also by its characteristic syllable combination, space structure is made as consonants and vowels are combined in single letter, then the combination develop into word, sentence, paragraph to make second, third space structure character. This character has significant impact on readability that is core function of typography. With this property, space structure character is regarded as very important component of Hangeul typography. First, space structure character of Hangeul typography is reviewed by relating it to visual perception of gestalt psychology and compared square-framed letter and framed latter By applying square-framed letter and framed latter in same sentence, legibility and readability were studied. Researcher has found that space structure character of Hangeul typography has significant impact on its function, and in terms of future design, it is very critical not only for design but also for communication environment as space structure formativeness of Hangeul typography interact with communication that is basic concept.

• Journal of the Korea Convergence Society
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• v.7 no.5
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• pp.269-277
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• 2016

This study was aimed to study the effects of adolescents' outdoor sports and e-sports activities on their holistic health. In order for this, adolescent holistic health has been divided into three categories: physical health, mental health, and social health; and reviewed existing research on outdoor sports and e-sports. The research has found several variables for measuring the correlation between the two types of sports. The variables cover four areas: 1) General Information, determined by gender, age, preferred sport, and length of play; 2) Physical Health, as measured by six questions in the basic PAPS (Physical Activity Promotion System) survey; 3) Mental Health, as measured by stress index, self-efficacy, subjective health, and self-esteem; and 4) Social Health, as measured by variables relating to family, friends, school, and society. A total of 36 questions were devised, with 1-4 questions in each area. Primarily it examined the mental health social health. As a result, it was found that three factors have a difference such that the significance of self satisfaction. family relationships, friendships is 0.064, 0.012, 0.088 respectably.