• Design & Manufacturing
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• v.14 no.2
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• pp.62-68
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• 2020

Recently, research on precise parts required in aerospace, ship, and automobile industries has been actively conducted. In this paper, electron beam drilling machining parameters were selected and experiments were conducted to compare processing characteristics analysis according to machining parameters through machining experiments of a vaporization amplification sheet to which STS 304 was applied. Also, as a result of measuring the machining. As the thickness gradually increased, it was confirmed that the electron beam could not reach the vaporization amplification sheet and thus melted on the surface of the material. As a result of the experimental analysis, it was analyzed that the vaporization explosion reaction of the vaporization amplification sheet was not normally performed due to the working distance (WD) according to the material thickness.

• 연구논문집
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• s.27
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• pp.75-86
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• 1997

Combined cycle power plant is a system where a gas turbine or steam turbine is used to produce shaft power to drive a generator for producing electrical power and the steam from the HRSG is expanded in a steam turbine for additional shaft power. Combined cycle plant is a one from of cogeneration. The temperature of the exhaust gases from a gas turbine ranges from $400^\circC$ to $600^\circC$, and can be used effectively in a heat recovery steam generator to produce steam. Combined cycle can be classed as a "topping(gas turbine)" and a "bottoming(steam turbine)" cycle. The first cycle, to which most of the heat is supplied, is called the topping cycle. The wasted heat it produces is then utilized in a second process which operates at a lower temperature level and is therefore referred to as a "bottoming cycle". The combination of gas/steam turbine power plant managed to be accepted widely because, first, each individual system has already proven themselves in power plants with a single cycle, therefore, the development costs are low. Secondly, the air as a working medium is relatively non-problematic and inexpensive and can be used in gas turbines at an elevated temperature level over $1000^\circC$. The steam process uses water, which is likewise inexpensive and widely available, but better suited for the medium and low temperature ranges. It, therefore, is quite reasonable to use the steam process for the bottoming cycle. Only recently gas turbines attained inlet temperature that make it possible to design a highly efficient combined cycle. In the present study, performance analysis of a dual pressure combined-cycle power plant is carried out to investigate the influence of topping cycle to combined cycle performance.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.395-402
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• 2011

As the consumer market for odor products grows, companies producing healthcare products are beginning to pay more attention to the emotional aspect of an odor product in order to differentiate their products from competitors. In the following research, the affective effect of odor product was investigated while focusing on relaxation and working contexts using orange and pine scents, since these are typical odors in current domestic market. Two empirical studies were carried out. First, in experiment I, 18 subjects, all of whom were university students, spent 20 minutes sitting comfortably on a sofa while electrocardiogram assessments were made. After a five-minute break, in experiment II, the same subjects were provided with both arithmetic and geometric questions and their electroencephalogram readings was recorded from eight channels. All subjects participated in three sessions - no odor, an orange scent, and then a pine scent - with a minimum time interval of 24 hours. The results show that in the context of a pine scent, both the activation ratio of subjects' parasympathetic system and those of the Sensory Motor Rhythm waves and Mid Beta waves were at the highest peak. Therefore, the pine scent helped the subjects to feel more comfortable and more focused at the same time. In other words, it gave them a state of meditated attention. In addition, it was found that the right brain was activated twice the intensity when the subjects worked through the geometric questions, whereas both sides of the brain were activated in equal magnitude during the process of arithmetic tasks. This replicates previous studies of the functional aspect of the right brain - being responsible for spatial and creative thinking.

• Journal of Korean Home Economics Education Association
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• v.34 no.1
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• pp.97-111
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• 2022

The purpose of this study is to systematically develop an impression management education program for career women by applying the Educational System Development Model [ESD] (Kwon, 1997) based on the research results of Hwang and Lee(2019) on social attractiveness. Since the previous impression management education programs were generally developed by content experts, few of them were developed systematically by considering the learner characteristics, clearly setting the educational goals, and structuring the contents accordingly. In this study, 'social attractiveness' defined by Hwang and Lee (2019) was considered as the educational goal of the impression management education program. In particular, this study focused on the design stage of the ESD model, set teaching goals based on the components of social attractiveness derived from previous studies, and conducted an analysis of teaching activities, the establishment of the educational goals at the specific function level, allocation of time, and establishment of an evaluation plan. The research process was intended to improve the learners' social image directly related to success through a systematic educational program designed to enhance the social attractiveness of working women with various hands-on activities and information. The impression management education program designed in this study has the educational advantage of a learner-centered education program configured to meet the needs and goals of career women. In addition, based on the ESD model, the sub-factors necessary for impression management were identified, and the curriculum was configured to reflect them through mutual communication between the instructor and learners. Therefore, this education program meets the basic requirements of impression management education necessary for career women and is expected to contribute to enhancing the social attractiveness of working women.

• Journal of the Korean GEO-environmental Society
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• v.20 no.5
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• pp.13-21
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• 2019

There are many cuts or natural rock slopes that remain stable for a long time in the natural environment with steep slopes ($65^{\circ}$ to $85^{\circ}$). In terms of design practice, the rock mass consisting of similar rock condition and geological structures is defined as a good continuum rock slope, and during the process of decision making angle of this rock slope, it will be important to establish the geotechnical properties estimating method of the continuum rock on the process of stability analysis in the early stages of design and construction. In this study, the stability analysis of a good continuum rock slope that can be designed as a steep slope proposed a practical method of estimating the shear strength by induced from the Hoek-Brown failure criterion, and in addition, the design applicability was evaluated through the stability analysis of steep rock slope. The existing method of estimating the shear strength was inadequate for practical use in the design, as the equivalent M-C shear strength corresponding to the H-B envelope changes sensitively, even with small variations in confining stress. To compensate for this problem, it was proposed to estimate equivalent M-C shear strength by iso-angle division method. To verify the design applicability of the iso-angle division method, the results of the safety factor and the displacement according to the change in angle of the cut slope constructed at the existing working design site were reviewed. The safety factor is FS=16~59 on the 1:0.5 slope, FS=12~52 on the 1:0.3 slope, most of which show a 10~12 percent reduction. Displacement is 0.126 to 0.975 mm on the 1:0.5 slope, 0.152 to 1.158 mm on the 1:0.3 slope, and represents an increase of 10 to 15%. This is a slightly change in normal proportion and is in good condition in terms of stability. In terms practical the working design, it was confirmed that applying the shear strength estimated by Iso-angle division method derived from the H-B failure criterion as a universal shear strength for a good continuum rock mass slope was also able to produce stable and economic results. The procedure for stability analysis using LEM (Limit Equilibrium Analysis Method) and FEM (Finite Element Analysis Method) will also be practical in the rock slope where is not distributed fault. The study was conducted by selecting the slope of study area as a good rock condition, establishing a verification for which it can be applied universal to a various rock conditions will be a research subject later on.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.145-156
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• 2020

Recently, as a culture that values work-life balance has become more important in society as a whole, interest in hobbies and leisure activities that will enrich life is increasing. This phenomenon is due to an increase in platforms where people can enjoy and learn hobbies online. Among them, craft-related content is growing rapidly, and as offline education has been brought online, learning immersion has been reduced online. Therefore, in this study, we want to identify current problems in online and offline craft learning and seek ways to improve UI design to solve them. To this end, we conducted a literature survey on the online learning platform, online craft learning platform and UI design, and based on this, conducted case investigation and analysis to derive the third stage of the learning process of the online craft learning platform. Subsequent surveys showed that as a result, the online craft learning platform was able to find improvements in terms of differentiating the content exploration process, visualizing the craft progress stage, ease of working with video tools, and providing smooth feedback, and in addition to the need for a device for active learning. Through the results of this study, we hope to expand the craft content market by making it easier for users to enjoy the contents provided on the online craft learning platform.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.2
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• pp.74-82
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• 1998

Combined cycle power plant is a system where a gas turbine or a steam turbine is used to produce shaft power to drive a generator for producing electrical power and the steam from the HRSG is expanded in a steam turbine for additional shaft power. The temperature of the exhaust gases from a gas turbine ranges from $400{\sim}650^{\circ}C$, and can be used effectively in a heat recovery steam generator to produce steam. Combined cycle can be classed as a topping and bottoming cycle. The first cycle, to which most of the heat is supplied, is a Brayton gas turbine cycle. The wasted heat it produces is then utilized in a second process which operates at a lower temperature level is a steam turbine cycle. The combined gas and steam turbine power plant have been widely accepted because, first, each separate system has already proven themselves in power plants as an independent cycle, therefore, the development costs are low. Secondly, using the air as a working medium, the operation is relatively non- problematic and inexpensive and can be used in gas turbines at an elevated temperature level over $1000^{\circ}C$. The steam process uses water, which is likewise inexpensive and widely available, but better suited for the medium and low temperature ranges. It therefore, is quite reasonable to use the steam process for the bottoming cycle. Recently gas turbine attained inlet temperature that make it possible to design a highly efficient combined cycle. In the present study, performance analysis of a 3 pressured combined cycle power plant is carried out to investigate the influence of topping cycle to combined cycle performance. Present calculation is compared with acceptance performance test data from SeoInchon combined cycle power plant. Present results is expected to shed some light to design and manufacture 150~200MW class heavy duty gas turbine whose conceptual design is already being undertaken.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.193-206
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• 2021

Artificial Intelligence (AI) has been inserted into people's lives through Intelligent Virtual Assistants (IVA), like Alexa. Moreover, intelligent systems have expanded to design studios. This research delves into designers' perspectives on developing AI-based practices and examines the challenges of adopting future intelligent design assistants. We surveyed UX/UI professionals in Brazil to understand how they use IVAs and AI design tools. We also explored a scenario featuring the use of Alexa Sensei, a hypothetical voice-controlled AI-based design assistant mixing Alexa and Adobe Sensei characteristics. The findings indicate respondents have had limited opportunities to work with AI, but they expect intelligent systems to improve the efficiency of the design process. Further, majority of the respondents predicted that they would be able to collaborate creatively with AI design systems. Although designers anticipated challenges in natural language interaction, those who already adopted IVAs were less resistant to the idea of working with Alexa Sensei as an AI design assistant.

• Journal of Intelligence and Information Systems
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• v.7 no.1
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• pp.81-95
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• 2001

Plant construction projects usually take much higher uncertainty and risks than the projects from other domains. This implies the importance of plant construction project management should be more emphasized than the other domain. Especially, the overall successes of the projects often depend on the performance of process planning and scheduling performed at the initial stage of the project. However, most plant construction projects suffer great difficulties in establishing proper process planning and scheduling timely because of unstructureness and dynamicity of environment of the project itself In this paper, we propose a knowledge-based process planning and scheduling approach in a plant construction domain to cope this problem. First, we modulize process planning knowledge and present the knowledge representation scheme. Second, we propose an inferencing mechanism to build a process planning for plant construction based on the represented process planning knowledge. Since our approach automate the initial process planning, which was usually done by manual way, it can improve the correctness and also completeness of the process plan and schedule by reducing the time to plan and allowing simulations on the various situation. We also design and implement this our approach as a real working system, and it is successfully applied to real plant construction cases from a leading construction company in Korea. Based on this success, we expect our approach can be easily applied to the projects of other areas, while contributing to enhancement in productivity and quality of project management.

• Journal of Engineering Education Research
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• v.7 no.2
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• pp.40-50
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• 2004

To keep pace with rapidly changing social and technological trends, the Department of Mechanical and System Design Engineering at Hongik University is in the process of updating teaching materials and learning methodologies while evaluating/revising our existing curriculum. In order to be better apprised of the employment needs and student aspirations, we have conducted three separate but related surveys by targeting experienced professionals and managers, alumni working in industries as practising engineers, and our current students. The surveys have furnished us with valuable insights that, we hope, will lead to a new curriculum and learning methods more in tune with needs of our students as well as their future employers. Among other findings, the analysis of the survey responses points towards expansion of integrated laboratory and design experiences, cultivation of improved written and oral communication capabilities involving individual and team efforts, and development of interdisciplinary courses encompassing related fields of engineering as well as emerging fields such as nano and information technologies.