• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.463-463
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• 2014

Dye-sensitized solar cells (DSSCs) have generated a strong interest in the development of solid-state devices owing to their low cost and simple preparation procedures. Effort has been devoted to the study of electrolytes that allow light-to-electrical power conversion for DSSC applications. Several attempts have been made to substitute the liquid electrolyte in the original solar cells by using (2,2',7,7'-tetrakis (N,N-di-p-methoxyphenylamine)-9-9'-spirobi-fluorene (spiro-OMeTAD) that act as hole conductor [1]. Although efficiencies above 3% have been reached by several groups, here the major challenging is limited photoelectrode thickness ($2{\mu}m$), which is very low due to electron diffusion length (Ln) for spiro-OMeTAD ($4.4{\mu}m$) [2]. In principle, the $TiO_2$ layer can be thicker than had been thought previously. This has important implications for the design of high-efficiency solid-state DSSCs. In the present study, we have fabricated 3-D Transparent Conducting Oxide (TCO) by growing tin-doped indium oxide (ITO) nanowire (NWs) arrays via a vapor transport method [3] and mesoporous $TiO_2$ nanoparticle (NP)-based photoelectrodes were prepared using doctor blade method. Finally optimized light-harvesting solid-state DSSCs is made using 3-D TCO where electron life time is controlled the recombination rate through fast charge collection and also ITO NWs length can be controlled in the range of over $2{\mu}m$ and has been characterized using field emission scanning electron microscopy (FE-SEM). Structural analyses by high-resolution transmission electron microscopy (HRTEM) and X-Ray diffraction (XRD) results reveal that the ITO NWs formed single crystal oriented [100] direction. Also to compare the charge collection properties of conventional NPs based solid-state DSSCs with ITO NWs based solid-state DSSCs, we have studied intensity modulated photovoltage spectroscopy (IMVS), intensity modulated photocurrent spectroscopy (IMPS) and transient open circuit voltages. As a result, above $4{\mu}m$ thick ITO NWs based photoelectrodes with Z907 dye shown the best performing device, exhibiting a short-circuit current density of 7.21 mA cm-2 under simulated solar emission of 100 mW cm-2 associated with an overall power conversion efficiency of 2.80 %. Finally, we achieved the efficiency of 7.5% by applying a CH3NH3PbI3 perovskite sensitizer.

• Journal of the Korean Geographical Society
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• v.50 no.6
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• pp.695-715
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• 2015

The history of Korean Pungsu can be approached from two perspectives. One is through the history of its theoretical formation and evolution, and the other is through the history of its social and cultural formation and evolution. The former, i.e. Pungsu theories, was produced and developed by intellectuals as an elaborate system of cosmic knowledge and logic. The latter, i.e. Pungsu culture, was consumed and adopted by various social groups in their spatial life practices. It was Chinese intellectuals that originally initiated and carried out the production, formation, and development of the fengshui theoretical system. Intellectuals in neighboring countries adapted Chinese fengshui to their local environment, incorporating their own historical and cultural features, and practiced this transformed and indigenized form of geomancy. The evolution of Korean Pungsu can be summarized as having the following five characteristics. First, Koreans accepted fengshui from China, pragmatically adapting it to fit the Korean natural and social environment, and then used it for social discourse on space. Second, Pungsu had a comprehensive and varied influence on Korean culture throughout its different historical periods. Third, combined with social thought led by differing social classes, Korean Pungsu existed as an element of social discourse. Fourth, Koreans' theoretical preferences of fengshui were for the landform method over the liqi (理氣) method. Fifth, the Bibo philosophy was a characteristic feature of Korean Pungsu.

• Journal of Korean Dental Hygiene Science
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• v.5 no.2
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• pp.97-104
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• 2022

Background: Due to the declining number of students preparing for university entrance exams , the quota of universities has been decreasing continuously. This situation became increasingly diverse as new media used online, mobile, and PR tools to continuously invite students. This study is aimed at offering the helpful data to plan an effective PR strategy by analyzing the correlation between the major selection and satisfaction of the department's social media usage among freshmen majoring in dental hygiene. Methods: The collected data from the self-reported survey with freshmen were analyzed using the SPSS 22.0 program. The survey items were motive to select the major, social media platform that subjects used, reasons to use the media, time to visit the department's social media platform, and satisfaction level on the department's social media platform, using a 5-point Likert Scale. Results: The reasons for choosing a major were given by 32.2% and 15.9% respondents, respectively, as the vision after graduation and practice facilities. 39.9% and 31.4% used Instagram and YouTube for social media platforms, respectively, for using social media platform; 26.9% and 26.3% visited the department's social media before and after entering the university, respectively; 46.4% and 24.9% used Instagram and YouTube for department social media; and they generally satisfied with the contents of the department's social media. 40.9% of them said that information from the department's social media was useful. 33.8% of them said the information from the department's social media exceeded their expectations. 46.8% of them answered that the department's social media made the department's image positive. 33.4% got interested in the major more due to the department's social media. According to 32.1% of respondents, the department's social media was helpful in deciding on a major. With 35.4%, a positive correlation was discovered between the department's practice facilities and satisfaction on the department's social media. Conclusion: It is thought that the department's social media should try continuously by uploading the contents to meet the users' needs on a regular basis and seeking the plans to be able to collect various opinions using surveys through the related social media so that students can select the major and, moreover, lead the positive direction to adapt the university life under the unfamiliar environment after admission.

• Journal of Embryo Transfer
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• v.28 no.2
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• pp.157-162
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• 2013

Methoxychlor (MXC) was developed to be a replacement for the banned pesticide DDT. HPTE [2,2-bis (p-hydroxyphenyl)-1,1,1-trichloroethane], which is an in vivo metabolite of MXC, has strong oestrogenic and anti-androgenic effects. MXC and HPTE are thought to produce potentially adverse effects by acting through oestrogen and androgen receptors. Of the two, HPTE binds to sex-steroid receptors with greater affinity, and it inhibits testosterone biosynthesis in Leydig cells by inhibiting cholesterol side-chain cleavage enzyme activity and cholesterol utilisation. In a previous study, MXC was shown to induce Leydig cell apoptosis by decreasing testosterone concentrations. I focused on the effects of MXC on male mice that resulted from interactions with sex-steroid hormone receptors. Sex-steroid hormones affect other organs including the kidney and liver. Accordingly, I hypothesised that MXC can act through sex-steroid receptors to produce adverse effects on the testis, kidney and liver, and I designed our experiments to confirm the different effects of MXC exposure on the male reproductive system, kidney and liver. In these experiments, I used pre-pubescent ICR mice; the puberty period in ICR mice is from postnatal day (PND) 45 to PND60. I treated the experimental group with 0, 100, 200, 400 mg MXC/kg b.w. delivered by an intra-peritoneal injection with sesame oil used as vehicle for 4 weeks. At the end of the experiment, the mice were sacrificed under anaesthesia. The testes and accessory reproductive organs were collected, weighed and prepared for histological investigation. I performed a chemiluminescence immune assay to observe the serum levels of testosterone, LH and FSH. Blood biochemical determination was also performed to check for other effects. There were no significant differences in our histological observations or relative organ weights. Serum testosterone levels were decreased in a dose-dependent manner; a greater dose resulted in the production of less testosterone. Compared to the control group, testosterone concentrations differed in the 200 and 400 mg/kg dosage groups. In conclusion, I observed markedly negative effects of MXC exposure on testosterone concentrations in pre-pubescent male mice. From our biochemical determinations, I observed some changes that indicate renal and hepatic failure. Together, these data suggest that MXC produces adverse effects on the reproductive system, kidney and liver.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.485-494
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• 2020

Club activities play an important role for college students in adapting to their college life. This study was therefore undertaken to investigate the effects of club activities on the communication skills and self-leadership of nursing students. Convenience sampling method was applied for 147 students enrolled in the nursing department of university in D city, of which 119 subjects participated in club activities. Data was collected from October 15 to November 30, 2019, and analyzed by applying 𝑥² test, t-test, and hierarchical multiple regression analysis, using the IBM SPSS/WIN 22.0 program. Results: Communication skill and self-leadership were above the middle level. Depending on the club activities, significant differences were obtained for grade (𝑥²=8.07, p=0.045), major satisfaction (𝑥²=8.26, p=0.010), and communication skill and behavior-focused strategies (t=4.48, p=0.036). Factors affecting communication skill were behavior-focused strategies, constructive thought pattern strategies, and activeness amongst club activities. Therefore, the numerous club activity experiences of subjects helped improve the communication skill which, in turn, helps improve self-leadership. Our study indicates the necessity to seek an educational strategy that encourages active club activities of nursing students, for improving the core competencies of professional nurses, encompassing communication skills and self-leadership.

• Journal of the Korea Society of Computer and Information
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• v.22 no.3
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• pp.147-153
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• 2017

The main subject of year 2016 Davos forum was "The 4th Industrial Revolution." Recently, interests and investment in drone market, so called industrial revolution in the sky is growing in many countries around the world. Before, drone was used for military purpose such as reconnaissance or attacking but today, it is used in various private sectors such as unmanned delivery service, agriculture, leisure activities, etc. Presently, many major countries in the world are already involved in the 'war without gunfire' to be dominant in this drone industry. Korean government also has announced an extreme relaxation of regulations for growing drone industry by opening a conference with Ministers related to economics. During the conference, business scope of drone which was limited to agriculture, photographing, and observation was expanded to all the fields except for cases hindering national safety and security. In terms of shooting purpose drone its process of receiving approval for flight and shooting is simplified to online registration. What is more, drone delivery service will be allowed in island areas such as Goheung, Yeongwol, etc from first term of year 2017. Finding the way to apply drone in criminal investigation is also speeding up. Recently, Public Safety Policy Research Center in Korean National Police University has inquired for research service and its result will be out around November. Likewise, although more and stronger foundation for supporting drone industry is made but there are still, some opinions saying that we should take a careful approach in consideration to the side effect such as abuse in crime. One may also try terror by placing a dangerous substance. If drone falls, it may hurt any civilians. Moreover, if shopping purpose drone is hacked, it may result in violation of privacy. Compared to America, Europe, and China, we are at the very beginning stage of drone industry and it is necessary to reorganize legal issues to grow this industry. This can be thought from two perspectives; first, the growth of drone industry is blocked by difficult regulations on Aviation Law and Radio Regulation Law. The second issue is the safety and privacy that are required for operating drone. For the advanced technologies to make human life more profitable, more active and proactive actions are required by criminal law side. In preparation to the second mechanical era where man and machines should go together, I hope that responsible preparation is required in all fields including the criminal law.

• (The)Study of the Eastern Classic
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• no.41
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• pp.37-59
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• 2010

This thesis is for clarifying a few aspects of 'Kyung(敬)' ideology and figures appearing in Yeheon(旅軒)'s poem. This ideology and figures is a kind of a imaginative thing that a poet designed. This feature is a very important subject of Yeheon(旅軒)'s poem world, so that we are going to make it clear. First, we focused his aspirations of virtual uncontaminated areas and found out his big store of life wisdom and knowledge. The second is we thought about a displaying a emphasis of proud spirit[氣像] in his own poem world, and we found that he saw things from an unworldly point of view. Finally we talked about several features of Yeheon(旅軒)'s poem world. Now we have to compare Yeheon(旅軒)'s poem and any other Dohakpa(道學派) poets for example Toegye(退溪), Hwejae(晦齋) etc. And we must clarify the whole poem world of Dohakpa(道學派). In the end, I'm so sure that we will get a prospect of their literature.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.17-26
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• 2011

Health care service's added value and sustainability has been formed, through the product developing about sports equipment and special equipment for disabled in order to improve the life quality, with the increasing population of elderly and the attention about health care. This research's design and 3 testing sections has been done according to design process for design development of functional bike. 1st test is done through researching from 4 aspects: structure, aesthetic, function and using. In the 2nd testing, 10 universal design items were used to evaluate 10 modeling samples, and sample F which has high evaluation overall was chosen. In 3rd test, evaluation was done from the user service scene about the mock-up with 1/4 scale size. PPP (product performance program) which is constructed with 60 evaluation items about functional bike's service was tested, and these items were fixed through discussing with experts. Through the result we knew the aesthetic elements had relationship with proportion, unity and typicality. In 10 items (55 survey items), the scores of items with physical exposure's minimization, simple and intuitively usage showed high, on the contrary, the other items' scores was very low, such as information delivery's consideration and thought, failure preventing. The evaluation will be done once more by health care experts, designers and elderly together if the physical model could be made for getting accurate measurement about above test result in the future.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.413-416
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• 2019

Alstroemeria (Alstroemeriaceae) is one of the most important cut flowers in international market. Especially, characteristics like long vase-life, various colors, tolerance to low temperature and a low energy requirement during cultivation have stimulated this success. Because of its characteristics such as low multiplication rates, time-consuming process and high risk of carrying viral disease, in vitro propagation techniques based on rhizome meristems culture have been developing nowadays. The callus induction has various cultivation sites compared with the direct plant generation method, and if the callus is maintained well, the plant differentiation can be performed simultaneously while maintaining the callus, so that it can be used for mass proliferation. In this study, we tested various hormones and cultivars for efficient callus induction. As a result of culturing between the nodes and the internodes, the callus began to be formed after 8 weeks, and the calli incidence in the nodes was higher than that between the internodes. Also, in the comparison of 2,4-D and picloram, the callus incidence rate was up to 2 times higher in the medium treated with 2,4-D. Using these results, it is thought that it will help establish the system of mass propagation system of Alstroemeria and cultivate new varieties.

• Journal of the Daesoon Academy of Sciences
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• v.32
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• pp.201-236
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• 2019

Heroes are the subjects who discover hope and provide people with courage and wisdom. At the same time, heroes have been known to renovate individuals and even societies on various dimensions throughout history. In recent times, a new academic field called 'heroism science' has emerged, leading to an era which focuses on their positive social functions and roles as reflected by war heroes from ancient times to ordinary civic heroes. However, attention is rarely paid to the ways in which their heroic acts have sometimes resulted in ethical problems such as the exertion of negative influences or the degradation of morality. Specifically speaking, people affected by the acts of heroes include not only beneficiaries but also specific subjects who could be considered victims. In a broad sense, the results caused by heroic acts could have an influence on harmony and unity in societies, the hero's nation, or even the entirety of the universe, and this is often overlooked. Given these realities, this study aims to understand how heroic acts simultaneously imply a positive side wherein cosmic restoration or reform are practiced and a negative side which carries out the destruction of life or the birth new disorders. In other words, the limitations of heroism is also worth consideration. To conduct this study, research on heroes will be comprehensively studied from various academic perspectives through previous documents on this subject. Western concepts that relate to heroes and heroic acts will be also illustrated. Reflections on Jeungsanist Thought, Korean heroes, and the limitation of heroes in the Former World will also be elucidated. Lastly, this study will discuss an authentic heroic figure that can be held up as an exemplary role model.