• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.347-348
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• 2008

The main goal of this work is advances in 1.0mm $\times$ 0.5mm light emitting diode using AlInGaN cell structure and display module. In the first place, we proposed $200{\mu}m{\times}200{\mu}m$ cell structure using AlInGaN. Secondly, we describe new type 1.0mm $\times$ 0.5mm blue and white LED fabrication procedure and results of an examination include mobile application.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.330-335
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• 2020

Silicon surface nanostructures, which can be easily prepared by electrochemical etching, have attracted considerable attention because of its useful physical properties that facilitate application in diverse fields. In this work, electrochemical and electrochemical-scanning tunneling microscopic (EC-STM) techniques were employed to study the evolution of surface morphology during the electrochemical etching of Si(111)-H in a fluoride solution. The results exhibited that silicon oxide of the Si(111) surface was entirely stripped and then the surface became hydrogen terminated, atomically flat, and anisotropic in the fluoride solution during chemical etching. At the potential more negative than the flat band one, the surface had a tendency to be eroded very slowly, whereas the steps of the terrace were not only etched quickly but the triangular pits also deepened on anodic potentials. These results provided information on the conditions required for the preparation of porous nanostructures on the Si(111) surface, which may be applicable for sensor (or device) preparation (Nanotechnology and Functional Materials for Engineers, Elsevier 2017, pp. 67-91).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.6
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• pp.16-23
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• 2016

This study was carried out to investigate how grade level and experiences when taking courses affect the creativity of engineering students in a Korean college. The sample group consisted of 372 engineering students of which 49.5% were first graders, 15.6% second graders, 22.6% third graders, and 12.4% fourth graders. They conducted self-report measures on a domain-general and domain-specific view of creativity. The engineering creativity test, developed by Kang and Yune (2015), is based on the domain-specific view of creativity and consists of four sub-factors: creative attitude, knowledge research, interest in engineering, and team work ability. The domain-general creativity test consists of three sub-factors. Analysis of the results led to the following conclusions: First, we found significant differences in engineering creativity between students depending on experiences in taking courses and tests; and, second, we discovered significant differences in integrative creativity among students depending on experiences in taking courses and tests, and/or grade level. These conclusions suggest that we should develop and apply appropriate strategies to enhance creativity in engineering education.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.948-953
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• 2006

The D-form of lactic acid is frequently detected in fermented foods, and an excessive dietary intake of D-lactic acid may induce metabolic stress in both infants and patients. This work was carried out to determine the prevailing microorganisms relevant to the accumulation of D-lactic acid in kimchi. Leuconostoc (Leuc.) mesenteroides and Leuc. citreum primarily synthesized D-lactate with a small quantity of L-form. Leuc. gelidum and Leuc. inhae evidenced patterns similar to this. Lactobacillus (Lb.) plantarum and Lb. brevis were shown to convert glucose into a balanced mixture of D-/L-lactic acid, whereas Lb. casei principally synthesized L-lactic acid and a very small quantity of D-lactic acid. When kimchi was incubated at 8 or $22^{\circ}C$, D-lactic acid was over-produced than L-form. Leuconostoc was determined as the primary producer between the initial to mid-phase of fermentation and Lb. plantarum or Lb. brevis seemed to boost D-lactic acid content during later stage of acid accumulation.

• Journal of IKEEE
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• v.17 no.3
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• pp.221-228
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• 2013

About functional parameters of a LED/UVLED (Light Emitting Diode/Ultra Violet LED), one of the most important parameters is the I-V characteristic. By researching factors affect to the I-V characteristic of uvled, we found that beside of the structure of the device itself, there is the influence of the electrode materials, electrode shapes, the process of wiring and packaging. In this work, we want to improve the performance of UVLED to find out the optimal mask design principles. The study is based on theoretical mathematical models, as well as the use of simulation software tool Comsol. From all results obtained, the team has improved mask design to manufacture electrodes for GaN-based UVLED. Electrode masks are designed by three softwares, which are Intellisuite, Klayout and AutoCad. Intellisuite masks would be used in fabrication simulation while Klayout and AutoCad are used to fabricate electrodes in experiments. As well as, we silmulated the structure of an uvled 355nm emission wavelength by TCAD software, in order to compare with uvled sample that has the same emission wavelength.

• Journal of Haehwa Medicine
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• v.22 no.2
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• pp.143-154
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• 2014

Objective : The purpose of this study is to establish a concept called as 'medical service' newly and to develop an reliable and valid scale that measures medical service. Methods : In order to accomplish these objectives, both conceptual study and empirical study were performed. In a conceptual study, 5 core factors(doctor, medical team, medical facilities, medical process, and hospital) and 24 sub factors were extracted with assistant by 7 experts, based on antecedent studies about components of medical service. In an empirical study, data was taken from 244 adults living in Seoul and Daejeon with the conceptually founded medical service scale. Results : Results of empirical study showed reliability and validity of the medical service scale. Internal consistency coefficient showed high score of .97 and, in accordance with the conceptual study, "medical treatment factor", "appearance factor", "personal factor", "trust factor" and "dissatisfaction factor" were extracted from the data as the five main factors. Conclusions : Finally, limitations of this study and directions for further studies are discussed. Acknowledgement : This work was supported by the Daejeon University Research Grant.

• ETRI Journal
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• v.34 no.5
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• pp.706-712
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• 2012

In previous work, novel maskless bumping and no-flow underfill technologies for three-dimensional (3D) integrated circuit (IC) integration were developed. The bumping material, solder bump maker (SBM) composed of resin and solder powder, is designed to form low-volume solder bumps on a through silicon via (TSV) chip for the 3D IC integration through the conventional reflow process. To obtain the optimized volume of solder bumps using the SBM, the effect of the volumetric mixing ratio of resin and solder powder is studied in this paper. A no-flow underfill material named "fluxing underfill" is proposed for a simplified stacking process for the 3D IC integration. It can remove the oxide layer on solder bumps like flux and play a role of an underfill after the stacking process. The bumping process and the stacking process using the SBM and the fluxing underfill, respectively, for the TSV chips are carefully designed so that two-tier stacked TSV chips are sucessfully stacked.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.197-203
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• 2004

A full finite element (FE)-based approach is presented for the precision analysis of the strip profile in flat rolling. Basic FE models for the analysis of the mechanical behavior of the strip and of the rolls are described in detail. Also described is an iterative strategy for a rigorous treatment of the mechanical contact occurring at the roll-strip interface and at the roll-roll interface. Then, presented is an integrated FE process model for the coupled analysis of the mechanical behavior of the strip, work roll, and backup roll in four-high mill. A series of process simulation are conducted and the results are compared with the measurements made in hot and cold rolling experiments.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.10 no.1
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• pp.87-95
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• 2003

Purpose: The purpose of this study was to identify nurses' knowledge of pain and provide basic data for development of pain management education programs. Method: The participants in the study were 764 nurses working at seven medical centers in Youngnam area. The instrument used in this study consisted of 22 items on pain knowledge. The data were collected between March 1 and June 30, 2002 using a self-administered questionnaire. Analysis of data was done using descriptive statistics, t-test, ANOVA and Scheffe test with the SPSS program. Result: 1) The average score for pain knowledge was 13.63 (total possible score, 22). 2) The highest item with correct response rate for knowledge of fain was identifying 'Tylenol as opioid or non-opioid.' and the lowest was for 'When opioids are used for pain relief for 3-6 months, what percent of patients are likely to develop opioid addiction?' 3) Nurses' knowledge of pain was significantly different according to age (F=7.040, p=.000), education (F=3.385, p=.034) and work career (F=6.101, p=.000). Conclusion: The above findings indicate that it is necessary to develop a comprehensive pain management education program and continuously provide the medical team with new knowledge about pain.

• Journal of Ocean Engineering and Technology
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• v.19 no.6 s.67
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• pp.86-91
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• 2005

Regarding some of tire important works in tire shipyard, like tire production process, quality control, and material handling, there are many elements that disturb tire work-flaw. For example, there are mistakes in manufacturing, delay of production, and poor quality. These kinds of disturbances are from tire delay of communication time between tire production field and tire management. Therefore, it would be possible to strengthen tire competitiveness of shipbuilding industries by applying tire information technology based on Wireless Local Area Network (Wireless LAN), in order to establish tire multi-possession of real time production information in limited large shipbuilding yard. In this study, tire construction concept of tire information system, based on Wireless LAN, is proposed to build communication infrastructures in shipyards. The various information regarding shipbuilding inspection, process management, and material flaw are analyzed and constructed to databases in tire middle ware system, as tire platform for using Personal Display Agent (PDA). At last, tire middle ware system, which delivers tire information, is developed by tire C$\sharp$ and Microsoft.net; also, tire PDA application system is structured in WinCE O/S, and is tested and evaluated under tire server linked condition.