• Journal of the Korean Society for Railway
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• v.17 no.2
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• pp.94-99
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• 2014

Recently, trends in new transportation system development have been primarily focused on sustainable and ecofriendly mobility solutions. The personal rapid transit (PRT) system has been considered a promising candidate in this category; its competitiveness is being improved through convergence with cutting-edge electric vehicle (EV) technologies. However, battery-powered vehicles pose difficult technical challenges in attempts to achieve reliable and efficient operation. In this study, a design approach for a solar-power assisted PRT system is presented with small-scale demonstrations aimed at circumventing challenges facing its adoption, as well as helping speed the transition to electric-powered ground transportation. From the results, it is expected that flexible photovoltaic (PV) cells will be able to supply 11% of the power required by the service equipment installed in a prototype vehicle. In particular, flexible photovoltaic (PV) cells are advantageous in terms of cost, weight, and design considerations. Most importantly, the cells' flexibility and attach-ability are expected to give them great potential for extended application in various areas.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.3
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• pp.279-287
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• 2014

Estrogen deficiency results in a reduction of skin quality and function in postmenopausal women. Over the past decade, many studies have supported that estrogen provides anti-aging effects as a result of the ability of estrogen to prevent skin collagen decline, restore skin elasticity, and increase skin hydration in postmenopausal women skin. Due to their structural similarity with estrogen, isoflavones have been called phytoestrogens. Photoprotective effects of isoflavones are well established while their estrogenic-like activities are not fully understood in human skin. In this study, we investigated whether daidzein, an effective isoflavone, has phytoestrogenic activity and induces transcriptional change of extracellular matrix components in dermal fibroblasts. We examined the luciferase activity of daidzein and ${\beta}$-estradiol using transiently transfected NIH3T3-ERE cells. The estrogenic receptor-dependent transcriptional activity was increased in a dose-dependent manner when treated with daidzein, with a maximum of 2.5-fold induction at $10{\mu}g/mL$ of daidzein compared with non-treated control. In addition, daidzein significantly in creased the expressions of collagen type I, collagen type IV, elastin, and fibrillin-1 in human dermal fibroblasts. By comparing with the effects of ${\beta}$-estradiol through out all the experiments, we confirmed that daidzein had estrogenic activity and function in fibroblasts. These results suggest that daidzein-based application, having both photoprotective and phytoestrogenic effects, may be a powerful approach for skin anti-aging of postmenopausal women.

• Current Optics and Photonics
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• v.1 no.2
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• pp.107-112
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• 2017

An adaptive optics system can be simulated or analyzed to predict its closed-loop performance. However, this type of prediction based on various assumptions can occasionally produce outcomes which are far from actual experience. Thus, every adaptive optics system is desired to be tested in a closed loop on an optical test bench before its application to a telescope. In the close-loop test bench, we need an atmospheric simulator that simulates atmospheric disturbances, mostly in phase, in terms of spatial and temporal behavior. We report the development of an atmospheric turbulence simulator consisting of two point sources, a commercially available deformable mirror with a $12{\times}12$ actuator array, and two random phase plates. The simulator generates an atmospherically distorted single or binary star with varying stellar magnitudes and angular separations. We conduct a simulation of a binary star by optically combining two point sources mounted on independent precision stages. The light intensity of each source (an LED with a pin hole) is adjustable to the corresponding stellar magnitude, while its angular separation is precisely adjusted by moving the corresponding stage. First, the atmospheric phase disturbance at a single instance, i.e., a phase screen, is generated via a computer simulation based on the thin-layer Kolmogorov atmospheric model and its temporal evolution is predicted based on the frozen flow hypothesis. The deformable mirror is then continuously best-fitted to the time-sequenced phase screens based on the least square method. Similarly, we also implement another simulation by rotating two random phase plates which were manufactured to have atmospheric-disturbance-like residual aberrations. This later method is limited in its ability to simulate atmospheric disturbances, but it is easy and inexpensive to implement. With these two methods, individually or in unison, we can simulate typical atmospheric disturbances observed at the Bohyun Observatory in South Korea, which corresponds to an area from 7 to 15 cm with regard to the Fried parameter at a telescope pupil plane of 500 nm.

• Polymer(Korea)
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• v.30 no.6
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• pp.519-524
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• 2006

Poly(4-vinyl pyridine) (PVP) and its copolymers, poly(4-vinyl pvridine- co-acrylamide) and poly(4-vinyl pyridine-co-allylamine), were synthesized and evaluated for application to organic solder-ability preservatives (OSP). The copolymers were synthesized by radical polymerization of vinyl pyridine in the presence of acrylamide or allylamine as a comonomer. Various kinds of polymers with different chemical composition were synthesized by varying the feed ratio of monomers and their low $M_w$ polymers can be obtained by adding 2-mercaptoethanol as a chain transfer agent during poly-merization. All the polymers showed good adhesion properties on Cu pad when they were spin-coated. Especially, allylamine -containing copolymers showed both good adhesion and solubility properties. Also, they exhibited better thermal stability than PVP homopolymer and such thermal properties were changed depending on the chemical composition and their $M_w$, which were evidenced by the measurement of oxygen induced temperature (OIT). From the OIT measurement, poly(4-vinyl pyridine- co-allylamine) was thermally stable up to $230^{\circ}C$ for 70 min in the 100% oxygen environment. As a result, allylamine-containing copolymers can be considered as a promising OSP coating material that has excellent thermal and adhesive properties applicable to the present microelectronic package processes.

• Education of Primary School Mathematics
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• v.20 no.1
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• pp.85-99
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• 2017

In order to improve mathematical problem-solving ability, there has been a need for research on practical application of meta-affect which is found to play an important role in problem-solving procedure. In this study, we analyzed the characteristics of the sociodynamical aspects of the meta-affective factor of the successful problem-solving procedure of small groups in the context of collaboration, which is known that it overcomes difficulties in research methods for meta-affect and activates positive meta-affect, and works effectively in actual problem-solving activities. For this purpose, meta-functional type of meta-affect and transact elements of collaboration were identified as the criterion for analysis. This study grasps the characteristics about sociodynamical function of meta-affect that results in successful problem solving by observing and analyzing the case of the transact structure associated with the meta-functional type of meta-affect appearing in actual episode unit of the collaborative mathematical problem-solving activity of elementary school students. The results of this study suggest that it provides practical implications for the implementation of teaching and learning methods of successful mathematical problem solving in the aspect of affective-sociodynamics.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.234-250
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• 1998

Bujeonghangamtang(扶正抗癌湯) has been used for cure of tumor as a traditional medicine without any experimental evidence to support the rational basis for its clinical use. This study was carroed out to evaluate the possible therapeutic or antitumoral effects of Bujeonghangamtang extract against tumor, and to carry out some mechanisms responsible for its effect. Some kinds of tumor were induced by .the typical application of 3-methylcholanthrene (MCA) or by the implantation(s.c) of malignant tumor cells such as leukemia cells(3LL cells) or sarcoma cells(Sl80 cells). Treatment of the Bujeonghangamtang water-extract (dailly 1mg/mouse, i. p.) was continued for 7 days prior to tumor induction and after that the treatment was lasted for 20 days. Against squamous cell carcinoma induced by MCA, Bujeonghangamtang decreased not only the frequency of tumor production but also the number and the weight of tumors per tumor bearing mice (TBM). Bujeongmngamtang also significantly suppressed the development of 3LL cell and S180 cell-implanted tumors in occurence-frequency and their size, and some developed tumors were regressed by the continuous treatment of Bujeonghangamtang extract into TBM. In vitro, treatment of Bujeonghangamtang extract had no effect on the growth of some kinds of cell line such as FsaII, A431 strain but significantly inhibited the proliferation of 3LL, S180 cells and augmented the DNA synthesis of mitogen-activated lymphocytes. Bujeonghangamtang also stimulated the migrative ability of leukocyte, the MIF and IL-2 production of T lymphocytes, but not IL 6 production of B cells. Bujeonghangamtang-administration to mice enhanced NK cells attivities. These results demonstrated that Bujeonghangamtang extract exhibited a significant prophylactic benefits against tumors and its antitumor activity was manifested depending on the type of tumor cells. And these results also suggested that effect of Bujeonghangamtang might be chiefly due to nonspecific enhancement of NK cell activities and cell-mediated immune responses.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.446-451
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• 1997

The primary alcohol groups of four kinds of polysaccharides (com starch, rice starch, sweet potato starch, and cellulose), with different structures and water solubilities, were oxidized to carboxyl groups using 2,2,6,6-tetramethyl-1-piperidine oxoammonium ion (TEMPO) at $25^{\circ}C$. The optimum pH, TEMPO content, and NaBr content for the TEMPO/hypobromite-catalyzed oxidation of the polysaccharides were $10.5{\sim}11.0$, 10 mmol/mol primary alcohol, and 0.49 mmol/mol primary alcohol, respectively. The oxidation degree for the primary alcohol group was more than 90% for all four kinds of the polysaccharides. The oxidation process greatly increased the water solubility of the polysaccharides. Water-insoluble polysaccharide such as cellulose became water-soluble to the extent of 8.42% (w/v). And also, the polysaccharides with very low water solubility (less than 0.10% (w/v)) such as com starch, rice starch, and sweet potato starch had high water solubility of approximately 45%(w/v). The gel-forming abilities with calcium ion were determined. The oxidized polysaccharides are new anionic polymers with unique structures that could have application as gums, gels, and films.

• Geophysics and Geophysical Exploration
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• v.3 no.2
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• pp.53-60
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• 2000

The server/client systems using the web protocol and distribution computing environment by network was applied to the MT data processing based on the Java technology. Using this network based system, users can get consistent and stable results because the system has standard analysing methods and has been tested from many users through the internet. Users can check the MT data processing at any time and get results during exploration to reduce the exploration time and money. The pure/enterprised Java technology provides facilities to develop the network based MT data processing system. Web based socket communication and RMI technology are tested respectively to produce the effective and practical client application. Intrinsically, the interpretation of MT data performing the inversion and data process requires heavy computational ability. Therefore we adopt the MPI parallel processing technique to fit the desire of in situ users and expect the effectiveness for the control and upgrade of programing codes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.163-173
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• 2020

In this study, on-site corporate instructors participated as student-cum-workers in a degree-linked high skills Meister course to improve job competency and practical ability as proposed in the Work-Study Career Vision. Evaluation questions were then developed and their validity was verified by assessing satisfaction related to expected goals in enhancing advanced training guidance and competency as an evaluator. Satisfaction assessment was conducted based on training preparation, training implementation, training effectiveness and training administration. The Delphi Method was adopted and a total of 48 items were developed in 6 categories under 4 main areas. There were 7 evaluation items on the satisfaction of training course development under training preparation, 21 evaluation items related to the satisfaction of Off-JT and OJT courses under training implementation, 16 evaluation items related to the satisfaction of increased competency as an on-site corporate instructor and the satisfaction of enhanced practical skills and skills application at work under training effectiveness, as well as 6 evaluation items to assess satisfaction with administrative support under training administration. The final conformity assessment was conducted based on the stability, content validity ratio, consensus and convergence indicators of the developed items. Results of this study do not only apply to quality management of the high skills Meister course which is being promoted as a pilot project for work-study programs, but also serves as a rationale that may be considered as a basic research tool in the collection of various opinions to derive overall system improvement factors for the work-study high skills Meister course.

• Journal of Acupuncture Research
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• v.31 no.1
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• pp.75-93
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• 2014

Objectives : This study was designed to establish medical trust realization system by finding factors influential to it using questionnaire. Methods : 277 subjects were participated in this study. After a treatment, we conducted a survey from April 1st to October 31th about medical service perception index, medical trust index, patient satisfaction index, patient reliability index, patient flow degree index, recall intension index, and hospital image index. To evaluate the influence of medical service perception with other 6 indexes, we statistically made regression analysis of the results through the survey. Results : By the results of the analysis, evaluation of hospital image influenced all 6 indexes. The systemicity of treatment process had an effect on 5 indexes except for the flow degree of patients. The humanity of medical team brought out the estimation of 4 indexes except for the patient flow degree and hospital image. The empathic ability of doctor and appropriacy of medical costs hold the next rank influencing 3 indexes. It reached the conclusion that the systemicity of medical team tend to determine the medical trust and patient reliability. The expertise, professional skill of doctor, the fault, commercial application, fame of medical team, the speed of treatment process, the newest and clean medical facility affected each one index. Conclusions : Korean medicine should find a way to consider the mind of patients for improving the medical quality through trust realization system, keeping up with times. As a result of this research, we can find out important causes which influence the trustful medical system. From now on, we should apply this result to actual treatment of psychology customized system. Also, more simple and clear questionnaire was organized through this research, it can be used to forward research to apprehend patient mentality more conveniently.