• Current Photovoltaic Research
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• 제5권3호
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• pp.89-94
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• 2017

We have examined the issues on the measurement of bifacial photovoltaic(PV) devices that should be considered in order to ensure a measurement accuracy beyond a certain level and the comparability between the bifacial PV devices. Based on the results of various experiments and previous studies, solutions for these measurement issues are suggested. The most significant technical issues in the performance measurement of the bifacial PV devices are 1) elimination of the effect due to the light reflection on the sample holder surface and 2) the measurement of the expected power generation gain in outdoor operation. The effect due to the light reflection on the sample holder surface can be eliminated by using an anti-reflective sample holder. In case of a reflective sample holder, if the bifacial device have a linear characteristic with respect to the irradiance of incident light, it has been confirmed (through some previous studies and additional experiment) that exact measurement results can be obtained by the correction of the measurement data. In addition, it was also confirmed that the expected power generation gain in the outdoor operation can be obtained by three different methods along with the basic concepts of the bifaciality coefficient, the albedo, and the effective front irradiance.

• Journal of Science and Technology Studies
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• 제1권2호
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• pp.423-438
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• 2001

The purpose of this study is to understand how a teacher's teaching can be changed while he or she teaches the same contents in different classes. The qualitative research method was used in this study. Data were collected from classroom observations, several in-depth interviews, and stimulated-recall interviews after each class. All the data were transcribed and analyzed interpretively, and then, the results of the analysis were checked by each participating teacher. The results are as follows: First, changes appeared in each class in terms of the teaching items, tools, sequence, and time, even though the same teacher taught the same contents. It showed that the teacher's teaching practice changed immediately and intuitively in class. Second, teachers tried to implement "exploratory teaching" or "move-testing teaching" to address the emerging problems during their teaching. They then reflected on and modified their own teaching. This type of change, which happened during the teaching practice, can be an example of "Reflection-in-practice." Thus, the results of this study can provide helpful insights into how teachers might adapt and reflect in their teaching. It suggests that teachers need to recognize their subconscious teaching changes and learn "Reflection-in-practice."

• Membrane Journal
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• 제15권3호
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• pp.247-254
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• 2005

Chitosan film has potential applications in agriculture, food, and pharmacy. However, films made only from chitosan lack gas barrier and have poor mechanical properties. For enhanced gas barrier and mechanical properties, chitosan/clay nanocomposites have been prepared with montmorillonite (MMT) which is a layered structure of clays and chitosan. The cationic biopolymer, chitosan is intercalated into $Na^+-montmorillonite$ through cationic exchange and hydrogen bonding process. Diluted acetic acid is used as solvent f3r dissolving and dispersing chitosan. Chitosan was intercalated or exfoliated in MMT and it was confirmed by X-ray diffraction method. D-spacing of the characteristic peak from MMT plate in chitosan/clay nanocomposites was moved and diminished. The thermal stability and the mechanical properties of the nanocomposites are measured by TGA and Universal Testing Machine. Gas permeability through the chitosan/clay nanocomposites films decreased due to increased tortuosity made by intercalation of clay in chitosan.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제18권6호
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• pp.585-595
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• 2017

This study investigates how the emotion-based learning motivation enhancement program influences learning motivation and social support of college students. The developed final program consists of Learning Motivation I, Learning Coaching, and Learning Motivation II, which has 12 sessions. In each session, every student was guided to have reflection time by writing self-evaluation and reflection paper. The participants were 38 students majoring in engineering at K-college located in G city who took one liberal arts subject based on psychology during the 1st semester in 2016 and who were divided into an experimental group (19 students) and a control group (19 students) by non-probability sampling method. In the experimental group, emotion-based learning motivation enhancement program was totally processed 12 times, one class in a week, by one main lecturer and one assistant lecturer. For data analysis, independent sample t-tests, paired samples t-tests, and review analysis were conducted. The study results are as follows. First, the experimental group participating in emotion-based learning motivation enhancement program had more significant differences in learning motivation, and both self-confidence and self-contentment among sub-components than the control group. Second, the experimental group had no significant differences in social support, compared with the control group. The impression writing analysis of the experimental group showed that this program affected learning motivation and social support. Lastly, the study discussions and implications are described.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• 제29권3호
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• pp.298-309
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• 2019

Objectives: This study aimed to investigate stages of safety and health culture change through a reflection on 40 years of hearing conservation history at a multinational company. Methods: The target workplaces were multinational companies with more than 1,000 employees. The research used the clinical case study and system analysis methods based on direct observation of the research from 1994 to 2009. The latter method performed an analysis of the equilibrium state of the cross-section in the given period and the longitudinal profile of the change during the given period. Results: The stages of cultural change are divided into five stages and summarized as follows. In the first stage, workplace noise was not widely recognized as a hazard, while in the second stage, the measurement of noise levels and audiometric testing were conducted under the Korean Occupational Safety and Health Act (KOSHA). The driving force for change in the second stage was the amendment of the KOSHA. In the third stage, noise came to be recognized as a hazard factor through awareness training. The driving force of change during the third stage was the strong executive power exerted by the audit of the industrial hygiene program from the US head office. In the fourth step, there was a change to actually reduce noise. The driving force in this stage was a change in company executives' risk perception resulting from lawsuits over noise-induced hearing loss and the task force team activities for culture change based on the action learning protocol. At the fifth stage, a 'buy quiet policy' was institutionalized. The management's experience that noise reduction was difficult was the motivation to manage noise from the time of purchase of equipment. Conclusions: The activities of a hearing conservation program are determined by the improvement of the legal system and by the way it is enforced. Noise control activities to reduce noise areas may be possible through the shared risk perception of noise-induced hearing loss and by a change agent role as a facilitator to implement noise control.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제22권4호
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• pp.195-205
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• 2021

As Coronavirus disease 2019 (COVID-19) became a pandemic, most nursing departments in Korea implemented online non-face-to-face practices rather than the existing practice method. This study was a qualitative study that analyzed the reflection diaries written by participants to understand what they experienced in the online non-face-to-face adult nursing practice process. The online non-face-to-face adult nursing practice was 90 hours for two credits and nine hours per day for a total of 10 days. This online practice consisted of computer-based simulation practice, computer-based nursing skills practice, video and educational material production, real-time online quiz, online lecture video, and discussion. As a result of analyzing the reflection diary, six categories, 13 subcategories, and 33 codes were derived. The six categories were 'Experience of various situations', 'Experience of new study', 'Fulfillment for the clinical practice', 'Building relations with professors', 'Fear of being a pre-nurse', and 'Ambivalence for the non-face-to-face practice'. These results are significant in that in the post-corona era, adult nursing practice was conducted as a non-face-to-face practice rather than a clinical practice institution, and various educational methods were operated. This study is expected to provide important basic data for the development and operation of non-face-to-face adult nursing practice.

• Food Engineering Progress
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• 제13권4호
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• pp.297-301
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• 2009

This study was performed to develop a prediction model of sugar content for strawberry. Near-infrared (NIR) spectroscopy has been prevailed for on-line and portable applications for non-invasive quality assessment of intact fruit. This work presents effects of illumination method and coating of reflection surface of light source on prediction result of sugar content. Effect of preprocessing methods was also examined. A low-cost commercially available VIS/NIR spectrometer was used for estimation of total soluble solids content (Brix). To predict sugar contents of strawberry, the best results were obtained with the spectrum data measured under intensive illuminations at three locations induced from the light source with fiber optic bundles. Gold coating of reflection surface of light source lamp gave favorable effect to prediction result. The best results in validation of PLSR model were $r_{SEP}$ = 0.891 and SEP = 0.443 Brix under OSC preprocessing and those of PCR were $r_{SEP}$ = 0.845, SEP $r_{SEP}$= 0.520 Brix, under no preprocessing.

• The Journal of the Korea Contents Association
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• 제21권10호
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• pp.723-737
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• 2021

This study attempted to understand the meaning and nature of the drinking experience of participants participating in self-sufficiency program with alcohol problems. For this, data were collected by conducting in-depth interviews with seven problem drinkers currently participating in the self-support work project at the local self-support center. It was analyzed by a phenomenological analysis method. As a result of the study, 26 topics, 7 thematic vowels, and 3 categories were derived. The essential meaning of the study participant's drinking experience is as follows. It turned out to be 'a sense of accomplishment and belonging to job performance', 'extension of work life', 'maintaining social relations', 'weekly control drinking for self-support', 'minimum effort not to damage the working environment', 'self-criticism and reflection on absence from work resulting from heavy drinking', 'self-awareness of drinking problems. Through the analysis, the participants drank with a sense of accomplishment and a sense of belonging to job performance, and drinking was considered to extend their work life and maintain social relationships. At the same time, on weekdays when participating in self-support work projects, they we refrain from drinking in their own way and make minimal efforts not to interfere with the working environment under a hangover. The Absent from work due to heavy drinking led to self-reflection and furthermore, it was confirmed that they were aware of their problem drinking.

• Journal of the Korean Chemical Society
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• 제64권6호
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• pp.401-415
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• 2020

The purpose of this study was to investigate the factors that affect the maintenance of the effect of mentoring for beginning science teachers. Mentee teachers for this study were ten mentee teachers who took part in the collaborative mentoring from 2014 to 2018. For this study, the videos of the first and fifth classes submitted during the mentoring program, mentors and mentees' journals, the videos of the classes recorded in 2019, questionnaires about reflection on the mentoring program, and interview materials were collected and analyzed. The result of this study is as follows. First, the reflective thinking was sustained after the mentoring program, and this played a crucial role in maintaining the effects of the mentoring. The group that showed the improvement of RTOP score had reflective thinking and made reflective practice on their teaching. Most participants in the group created the classes of constructivism based on self-reflection on their classes. However, no positive changes in the classes occurred to mentee teachers who couldn't have reflective thinking. Second, reflective practices during the mentoring program exerted a strong influence on the teaching method of mentee teachers. The group of the improvement in RTOP score strived to apply student-centered model of instruction to their classes. It was showed that most mentee teachers in the group kept applying the student-centered model to their classes after the mentoring was completed. These results indicate reflective thinking and reflective practice are crucial factors to the effect of the mentoring and its maintenance.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제21권12호
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• pp.10-15
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• 2020

Ultraviolet rays, which have wavelengths smaller than 400 nm, are very harmful to the eyes. Recently, high-energy visible light was also revealed to be harmful to retinal cells. Therefore, polymer eyeglass lenses that can block UV and high-energy visible light are needed for eye health. In this study, high-refractive-index polymer eyeglass lens, n=1.67, were manufactured using the injection-mold method with the m-xylene diisocyanate monomer, 2,3-bis((2-mercaptoethyl)thio)-1-propanethiol monomer, benzotriazole UV absorber, release of alkyl phosphoric ester, dye mixture of CI solvent violet 13, and catalyst of dibutyltin dichloride mixture. A multi-layer anti-reflection coating was applied to manufactured polymer eyeglass lenses for both sides using an E-beam evaporation system. The optical properties of the manufactured lenses with the UV and high-energy visible light-blocking function were analyzed by UV-visible spectrophotometry. As a result, the polymer eyeglass lens with a UV absorber of 0.5 wt. % blocked 99% of UV and high-energy visible light shorter than 411 nm. The average transmittance of the polymer eyeglass lens with a UV absorber of 0.5wt.% was 97.9% in the range of 460 ~ 660 nm for photopic eye sensitivity higher than 10%. Therefore, clear image acquisition in photopic vision is possible.