• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.472.2-472.2
• /
• 2014

현재 결정질 실리콘 태양전지의 전 후면 전극의 형성은 스크린 프린팅 방법이 주를 이루고 있다. 스크린 프린팅 방법은 쉽고 빠르게 인쇄가 가능한 반면 단가가 높고 금속 페이스트에 첨가된 여러 혼합물에 의해서 전극과 기판 사이의 저항이 크다는 단점이 있다. 본 논문에서는 도금을 이용하여 태양전지의 전극을 형성한 후 태양전지의 전기적 특성을 비교하였다. 또한 단일반사방지막($SiN_x$) 증착 후 도금을 이용한 전극 형성 시 반사방지막의 pin-hole에 의해 전극 이외의 표면에 도금이 되는 ghost plating 현상이 발생하게 되는데, 이를 방지하기 위해 thermal oxidation을 이용하여 SiO2/SiNx 이중반사 방지막을 증착함으로써 ghost plating을 최소화 시켰다. Ni을 이용하여 전극과 기판 사이의 저항을 낮추었으며, 주요 전극은 Cu 도금을 사용함으로써 단가를 낮추었으며 마지막으로 Cu전극의 산화를 방지하기 위해 Ag을 이용하여 얇게 도금하였다. 실험에 사용된 Si 웨이퍼 특성은 p-형, $156{\times}156mm2$, $200{\mu}m$, $0.5{\sim}3.0{\Omega}{\cdot}cm$ 이다. 웨이퍼는 표면조직화, p-n접합 형성, 반사방지막 코팅을 하였으며 스크린 프린팅 방법을 이용해 후면 전극을 인쇄하고 열처리 과정을 통해 전극을 형성하였다. 이 후 전면에 레이저를 이용해 전극 패턴을 형성한 후 도금을 실행하여 태양전지를 완성하였다. 완성된 태양전지는 솔라 시뮬레이터, QE 및 TLM패턴을 이용하여 전기적 특성을 분석하였으며, SEM과 linescan, 광학현미경 등을 이용하여 전극을 분석하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.10a
• /
• pp.709-711
• /
• 2012

Recently the research convenient for the user interface for the user interface technology that can be applied to the UI according to user's choice being made. To this end, the W3C is underway in a variety of devices from N-Screen service, consistent service delivery and the user's preferences according to UI to support adaptive services for a variety of research environments. In this paper, we studied the basic model-based user interface technology to develop a UI for the user's convenience. Web application applications apply measures will be used to apply the technology acquisition, and next-generation Web applications.

• Proceedings of the KIPE Conference
• /
• 2006.06a
• /
• pp.403-405
• /
• 2006

Over the years, plasma display panel (PDP) manufacturers have impressed the flat panel display industry with yet another new product essentially having the merits of a larger screen size. Since larger size implies higher power ratings, voltage/current ratings of the power devices used have become a rising concern. Another important concern is the brightness of PDP, one way of increasing which is by operating the PDP at higher frequencies. In order to address the above issues, a transformer coupled sustain-driver for AC-PDP is proposed During the transition time, the two windings of the transformer greatly boost up the displacement current flowing through the panel capacitance and hence enable a fast inversion of the voltage polarity with practical values of resonant inductance. In the proposed topology, the resonant inductance can be increased by a factor of $(n+1)^2$ as compared to prior approaches. Increased inductance results in lower current stresses. Moreover, high frequency operation is possible by using higher value of n (turn ratio of the transformer). The operational principle and design procedure of the proposed circuit are presented with theoretical analysis. The validity of the proposed sustain driver is established through simulation and experimental results using a 42-in PDP

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.4
• /
• pp.934-941
• /
• 1999

This study was performed to investigate the effect of family type on the nutrient intake and nutritional status in elderly women. Blood samples and anthropometric data of elderly women aged from 60 to 78 years were collected in 1996, who visited a health examination center in Seoul to screen their health status. They were divided into two groups by their family type, one was extended family(extended family elderly, n=37) and the other was independently living(independently living, n=29). Nutrients intake was measured by interview using a simplified questionaire. Albumin, cholesterol, triglyceride(TG), hemoglobin (Hb), hematocrit, Ca, Mg, and alkaline phosphatase activity of serum were analyzed. Intakes of energy, protein, carbohydrate, Fe, vitamin A, niacin, thiamin, riboflavin, and vitamin C were not different between the two groups. However, fat and Ca intakes were higher(p<0.05) in extended family elderly than indepen dently living elderly. There are no significant difference in hematocrit value and serum concentrations of Hb, TG, and Ca. Serum Mg and cholesterol levels tended to be higher in extended family elderly. However, serum albumin level was lower(p<0.05) in extended family elderly. These results show that the indepen dently living elderly women had intakes of daily energy, fat and Ca compared to the extended family elderly. Therefore, the nutritional education for the independently living elderly will be focused on the health risk resulted from less intakes of Ca and total energy.

• Journal of Practical Engineering Education
• /
• v.7 no.2
• /
• pp.97-105
• /
• 2015

In this paper, we have selected physical computing as the focused learning elements with the PBL-based programming instruction method. Students experienced physical computing by using Arduino. Development of robot using Arduino can create an effective educational environment and also provide solutions for lack of environmental conditions, such as time or spatial factor restrictions and excessive expense issues; these are major obstacles to developing robot programming education. Finally, we analyzed the effects on growth of student's logical thinking and problem solving abilities by demonstrating the Arduino application courseware to the field of education.

• Journal of muscle and joint health
• /
• v.18 no.1
• /
• pp.16-27
• /
• 2011

Purpose: The purpose of this study was to investigate the effects of a visual feedbackbased balance training, using force platform biofeedback, on the postural balance of elderly faller. Methods: Fifty one community-dwelling older adults (aged 66-88 years) with a recent history of fall participated in the study. Participants were randomized to an experimental group (EG, n=25) and to a control group (CG, n=26). The EG participated in training sessions three times/week for 6 weeks. Visual feedbackbased balance training with the a computerized force platform with visual feedback screen was used in the experimental group. Static balance (center of gravity) and dynamic balance (Functional reach test, Timed "Up & Go" test, Berg balance scale) were assessed before and after end of training. Results: A significant improvement in static balance and dynamic balance were demonstrated within the EG (p<.05), but not in the CG. Conclusion: Visual feedback-based balance training may be an effective intervention to improve postural balance of elderly fallers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.759-761
• /
• 2011

Recently, there is study about interface for user convince. this users interface technology can apply to UI depend on user choice. For that, W3C study various technology which is N-screen service on different device, provide consistent service, and UI adjust service depends on user preference. Therefore, we need UI study based on this model and standard technology. In this paper, study UI technology based on basic model to develop UI for user's convenience. So it can be useful to apply next-generation Web applications and secure web-application measure plans.

• Toxicological Research
• /
• v.16 no.2
• /
• pp.109-116
• /
• 2000

The purposes of our study were to optimize the conditions of the screening and testing methods for endocrine disruptors, to characterize these assays using several compounds with well-defined endocrine activity, and to compare the sensitivity between these assays currently undergoing validation. Two in vitro test systems, MCF-7 cells proliferation (E-screen assay) and competitive binding to estrogen receptors (ER) were selected to evaluate the estrogenic effects. 17$\beta$-Estradiol (E2) and diethylstilbestrol (DES) were used as a positive control in vitro test. Also, E2 and ethinyl estradiol (EE) were used as a positive control in vivo uterotrophic assay. In in vitro test, E2 and DES showed a strong estrogenic response at concentration of 1.0 nM. In uterotrophic assay, E2 (0.3 $\mu\textrm{g}$/kg) and EE (0.3 $\mu\textrm{g}$/kg) produced a significant increase in uterus and vagina weight in both immature and ovariectomized rats. Although we did not com-pared the specificity between in vivo and in vitro assays, these assay systems may serve as a good tool for endocrine disruptors screening methods. Our data indicate that these assay systems exhibit some difference in their sensitivity to the same estrogenic compounds. Therefore, as a first rapid screening assay for estrogenic activity qf unknown chemicals, at least two assay systems should probably be carried out with a view of high sensitivity and standardization conditions. Also, a careful validation tests are necessary to obtain a reasonable degree of reproducibility.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.250-253
• /
• 2007

An evaporated Ti/Pd/Ag contact system is most widely used to make high-efficiency silicon solar cells, however, the system is not cost effective due to expensive materials and vacuum techniques. Commercial solar cells with screen-printed contacts formed by using Ag paste suffer from a low fill factor and a high shading loss because of high contact resistance and low aspect ratio. Low-cost Ni and Cu metal contacts have been formed by using electroless plating and electroplating techniques to replace the Ti/Pd/Ag and screen-printed Ag contacts. Ni/Cu alloy is plated on a silicon substrate by electro-deposition of the alloy from an acetate electrolyte solution, and nickel-silicide formation at the interface between the silicon and the nickel enhances stability and reduces the contact resistance. It was, therefore, found that nickel-silicide was suitable for high-efficiency solar cell applications. The Ni contact was formed on the front grid pattern by electroless plating followed by anneal ing at $380{\sim}400^{\circ}C$ for $15{\sim}30$ min at $N_{2}$ gas to allow formation of a nickel-silicide in a tube furnace or a rapid thermal processing(RTP) chamber because nickel is transformed to NiSi at $380{\sim}400^{\circ}C$. The Ni plating solution is composed of a mixture of $NiCl_{2}$ as a main nickel source. Cu was electroplated on the Ni layer by using a light induced plating method. The Cu electroplating solution was made up of a commercially available acid sulfate bath and additives to reduce the stress of the copper layer. The Ni/Cu contact was found to be well suited for high-efficiency solar cells and was successfully formed by using electroless plating and electroplating, which are more cost effective than vacuum evaporation. In this paper, we investigated low-cost Ni/Cu contact formation by electroless and electroplating for crystalline silicon solar cells.

• Journal of Korean Ophthalmic Optics Society
• /
• v.4 no.1
• /
• pp.73-76
• /
• 1999

Screening of strabismus was followed in 1306 healthy elementary school students from 8 to 13 years old. The cover-uncover test with M1N GLASSES was used to screen strabismus for all of students and then we examined abnormal students by the prism cover test. Finally 16 students were strabismus. So the cover-uncover test with MIN GLASSES was a good method to screen strabismus because of easy and simple testing. The number of strabismus was 16 patients who consisted in from 10 to 13 years old, and girls(2.4%) was 3 times more than boys(0.9%). The type of 16 strabismus was only heterophoria which consisted in 8 patients of exophoria, 7 patients of esophoria and 1 patient of hyperphoria. So the rate of exophoria and esophoria was almost same. 3 patients was ametropic amblyopia by testing visual acuity, and all of patients were normal color vision by color testing.