• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.1
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• pp.15-24
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• 2010

Photovoltaic solar cells are all in the incident because they are not converted into electrical energy, high-efficiency solar cells in order to reduce the loss of elements must be. Significant factor in the loss of solar cells, optical loss and electrical loss can be divided into. Optical losses occur when the sun will be joined on the surface of the reflection, the shadow loss due to electrodes, and the losses are in the solar wavelengths. Commercialization is currently the most common solar cells on the front of the light incident on the electrode is formed. Therefore, the shadow caused by the electrode to cover the dead area of the sun, due to factors that hinder the absorption of sunlight which is shadowing them and conversion efficiency of solar cells is the inhibition factor. These barriers to eliminate the electrode linewidth reduces the shadowing to reduce, but simply of the electrode line width is reduced electrode area by reducing the series resistance elevates this because to improve the electrode Aspect ratio(height/width) to increase Ag development of paste is required. In this study, aspect ratio of screen-printing method to increase the electrode Ag paste composition of the binder for the characterization of rheology in the shadow of the electrode by reducing the optical loss of the photoelectric conversion efficiency of solar cells to boost the performance measures was. Properties and printability of the paste, the binder resin sintered characteristics that affect the thermal properties are excellent with a good screen printability acrylic resin, ethyl cellulose, using a resin were evaluated. Prepared paste rheology properties, was formed to evaluate the electrode conductivity and aspect ratio.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.3
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• pp.215-222
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• 1995

Nb doped strontium titanate single crystals were grown by the floating zone method. The doping amount of $Nb_2O_5$ was 0.2 wt %. Those crystals were grown in air and N z atmosphere and the growth rate was 5 mmlhr and rotation speed of upper and lower shaft was 30 rpm. The shapes of melt - feed rod interface depending on sintering temperatures were observed. In air atmosphere, the flow rate of air was 1.5 ${\ell}/min$ and in $N_2$ atmosphere, that of $N_2$ gas was 0.5 ${\ell}/min$. As grown crystals were analyseQ by XRD, Laue back - reflection and chemical etching. After annealing in $N_2$ atmosphere, resistivities of crystals were measured and the activation energies of each samples were calculated.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1897-1904
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• 2006

Home service robot must recognize and build map for indoor and components of the house such as furniture and chair etc. The previous researcher has developed a indoor map building system by using CCD camera and ultra sonic sensor. %no stems have some problem in such a way that (1) a distun resolution can be changed according to the number of pixel when we use a CCD camera system, (2) a measured distance can be decreased when it transmitted to the rubber because of being absorbed the sound energy. This paper represents an intelligent sensor controller of module has been developed by using optic PSD(Position Sensitive Detector) sensor any at a low price. To deduce the switching noise from beam power module and diffused reflection noise, we proposed a heuristic soft filter. The performance of the developed system was compared with ultra sonic sensor system by detecting the indoor wall environment. Some experiments were illustrated for the validity of the developed system.

• Journal of the Korean Society of Costume
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• v.41
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• pp.207-223
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• 1998

The purpose of this study is to abstract the image from black dress, which has been favored by many people regardless of the times and examine it throughout the history of drss and thereby clearly define the images that black limplies in dress. Color image is a visual symbol, an image that forms through a combination of visual stimulus created by color, coupled with all the external factors related to it. Black is a one-dimensional color, of which the impact is subjective to its energy, which depends on light reflected on the object, and its texture. Therefore, black projects different images, depending on its surroundings. In general, black has had negative connotations in the Western culture. In dress, however, it has implied other various images different from the general negative ones. By combining general images of black and those exprssed in dress, major images of black were categorized into dignity, elegance, eroticism, asceticism and tragedy. Dignity is a category similar to the sublime. Dress with dignity has sharp contours and is generally made of velvet or silk which can be characterized by their splendor and voluminous-ness, exaggerating the body of a person wearing it. Such costume is mostly found in powerful countries in history such as Burgundy Court in the 15C, Spain in the 16C. Netherlands in the 17C. Elegance evokes grace and beautifulness. It includes elegance, grace, beauty and dandyism as subcategories or silk. Good examples are dandies' black costume and Ladies black and white dressees in the 19C. Eroticism is an image which expresses sexual attractiveness. Costume with eroticism is made of velvet or silk, which project sumptuousness through reflection. Such costumes expose parts of the body or are tightly tailored in order to emphasizes body contours. Asceticism means restraint from physical and mental desires. Costume with asceticism makes a person wearing it look smaller by covering the whole body. Puritan's black dresses and Bourgeoisie's black suit are good examples. Tragedy is anguish. sorrow. Black costume with grievous feelings such as mourning dresses is made of lusterless textile concealing most of the body except for the face.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.676-679
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• 2009

The bottom-simulating reflector (BSR) is the most commonly observed seismic indicator of gas hydrate in the Ulleung Basin, East Sea. We processed ten representative seismic reflection profiles, selected from a large data set, for amplitude variation with offset (AVO) analysis of the BSR to estimate gas-hydrate concentrations. First, BSRs were divided into five groups based on their seismic amplitudes and associated sediment types: (1) very high-amplitude BSRs in turbidite/hemipelagic sediments, (2) high-amplitude BSRs in debris-flow deposits, (3) moderate-amplitude BSRs in turbidite/hemipelagic sediments, (4) very low-amplitude BSRs in debris-flow deposits, and (5) very low-amplitude BSRs in seismic chimneys. The AVO responses of the group 1 and 3 BSRs are characterized by a rapid decrease and a relatively slow decrease in magnitude with offset, respectively. The AVO response of the group 2 BSR is characterized by a relatively slow increase in magnitude with offset. The AVO responses of the groups 4 and 5 BSRs are characterized by a flat AVO with very small zero-offset amplitude. Theoretical AVO curves, based on the three-phase Biot theory, suggest that the group 1 and 3 BSRs may be related to high (> 40%) concentrations of gas hydrate whereas the group 2 BSRs may indicate low (< 20%) concentrations of gas hydrate. The AVO responses of the group 4 and 5 BSRs cannot be compared with the theoretical models because of their very small zero-offset amplitudes. The comparison of the AVO response of the BSR at the UBGH-04 well with theoretical models suggests about 10% gas-hydrate concentration above the gas-hydrate stability zone.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.112.1-112.1
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• 2011

The back contact solar cell (BCSC) has several advantages compared to the conventional solar cell since it can reduce grid shadowing loss and contact resistance between the electrode and the silicon substrate. This paper presents the effect of the surface texturing of the silicon BCSC by varying the texturing depth or the texturing gap in the commercially available simulation software, ATHENA and ATLAS of the company SILVACO. The texturing depth was varied from $5{\mu}m$ to $150{\mu}m$ and the texturing gap was varied from $1{\mu}m$ to $100{\mu}m$ in the simulation. The resulting efficiency of the silicon BCSC was evaluated depending on the texturing condition. The quantum efficiency and the I-V curve of the designed silicon BCSC was also obtained for the analysis since they are closely related with the solar cell efficiency. Other parameters of the simulated silicon BCSC are as follows. The substrate was an n-type silicon, which was doped with phosphorous at $6{\times}10^{15}cm^{-3}$, and its thickness was $180{\mu}m$, a typical thickness of commercial solar cell substrate thickness. The back surface field (BSF) was $1{\times}10^{20}\;cm^{-3}$ and the doping concentration of a boron doped emitter was $8.5{\times}10^{19}\;cm^{-3}$. The pitch of the silicon BCSC was $1250{\mu}m$ and the anti-reflection coating (ARC) SiN thickness was $0.079{\mu}m$. It was assumed that the texturing was anisotropic etching of crystalline silicon, resulting in texturing angle of 54.7 degrees. The best efficiency was 25.6264% when texturing depth was $50{\mu}m$ with zero texturing gap in case of low texturing depth (< $100{\mu}m$).

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.50-53
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• 2006

Regional geophysical surveys and geological cal studies on natural gas hydrate (NGH) in the East Sea were carried out by the Korea Institute of Geoscience and Mineral Resources (KIGAM) from 2000 to 2004. 16 piston cores, 2270 L-km of multi-channel reflection seismic (MCRS) data and 730 L-km of 3.5kHz Chirp data obtained from the southwestern part of the deep-water Ulleung Basin were analyzed in this study. In piston cores, cracks generally developed parallel to bedding suggest significant gas content. The core analyses showed high total organic carbon (TOC) content, sedimentation rate and heat flow of sediments. These are in favor of the general ion of substantial biogenic methane, which can form the NGH within the stability zone of the near seafloor sediments in the study area. The cores generally show also high residual hydrocarbon gas concentrations for the formation of natural gas hydrates The geophysical indicators of the presence of gas and/or NGH such as bottom simulating reflectors (BSRs), seismic blank Bones, pockmarks and gas seeping features were well defined on the MCRS and Chirp data.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.398-398
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• 2013

The electronic properties and the local structure of tantalum oxide thin film with variation of oxygen flow rate ranging from 9.5 to 16 sccm (standard cubic centimeters per minute) have been investigated by X-ray photoelectron spectroscopy (XPS), Reflection Electron Energy Loss Spectroscopy (REELS), and X-ray absorption spectroscopy (XAS). The XPS results show that the Ta4f spectrum for all films consist of the strong spin-orbit doublet $Ta4f_{7/2}$ and $Ta4f_{5/2}$ with splitting of 1.9 eV. The oxygen flow rate of the film results in the appearance of new features in the Ta4f at binding energies of 23.2 eV, 24.4 eV, 25.8, and 27.3 eV, these peaks attribute to $Ta^{1+}$, $Ta^{2+}$, $Ta^{4+}$/$Ta^{2+}$, and $Ta^{5+}$, respectively. Thus, the presence of non-stoichiometric state from tantalum oxide ($TaO_x$) thin films could be generated by the oxygen vacancies. The REELS spectra suggest the decrease of band gap for tantalum oxide thin films with increasing the oxygen flow rate. The absorption coefficient ${\mu}$ and its fine structure were extracted from the fluorescence mode of extended X-ray absorption fine structure (EXAFS) spectra. In addition, bond distances (r), coordination numbers (N) and Debye-Waller factors (${\sigma}^2$) each film were determined by a detailed of EXAFS data analysis. EXAFS spectrapresent both the increase of coordination number of the first Ta-O shell and a considerable reduction of the Ta-O bond distance with the increase of oxygen flow rate.

• The Journal of the Acoustical Society of Korea
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• v.15 no.6
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• pp.52-58
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• 1996

Using the acoustic resonances and oscillatory pulsations considered as the branch of wave technologies, the concept of the acoustic resonance diffusers for waste water treatment which maximize the oxygen transfer efficiency in gas-liquid two phase medium have been proposed, and studies for the principles and performance tests were accomplished. Besides, the design concepts for the low pressure Helmholtz resonator, cylinder and annular type reflection resonator and combined type resonance system have been implemented. The acoustic resonance energy which can speed up the mass transfer process increase the oxygen transfer efficiency, and periodic pulsations generated from the instability of air jet from nozzle make very small air bubbles. Then, the annular type jet resonator(AJR) applying these two principles successfully was evalulated as the most promising device and also the efficiency showing $20{\sim}30%$ better than conventional diffusers has been verified experimentally.

• Nutrition Research and Practice
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• v.9 no.4
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• pp.420-424
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• 2015

BACKGROUND/OBJECTS: When the functions involved in the ingestion of food occurs failure, not only loss of enjoyment of eating, it will be faced with protein-energy malnutrition. Dysmasesis and difficulty of swallowing occurs in various diseases, but it may be a major cause of aging, and elderly people with authoring and dysmasesis and difficulty of swallowing in the aging society is expected to increase rapidly. SUBJECTS/METHODS: In this study, we carried out a survey targeting nutritionists who work in elderly care facilities, and examined characteristics of offering of foods for elderly and the degree of demand of development of easily chewable and swallowable foods for the elderly who can crush foods and take that by their own tongues, and sometimes have difficulty in drinking water and tea. RESULTS: In elderly care facilities, it was found to provide a finely chopped food or ground food that was ground with water in a blender for elderly with dysmasesis. Elderly satisfaction of provided foods is appeared overall low. Results of investigating the applicability of foods for elderly and the reflection will of menus, were showed the highest response rate in a gelification method in molecular gastronomic science technics, and results of investigating the frequent food of the elderly; representative menu of beef, pork, white fish, anchovies and spinach, were showed Korean barbecue beef, hot pepper paste stir fried pork, pan fried white fish, stir fried anchovy, seasoned spinach were the highest offer frequency. CONCLUSIONS: This study will provide the fundamentals of the development of easily chewable and swallowable foods, gelification, for the elderly. The study will also illustrate that, in the elderly, food undergone gelification will reduce the risk of swallowing down to the wrong pipe and improve overall food preference.