• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.670-674
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• 2012

The photovoltaic performance of solid-state dye-sensitized solar cells employing hole transport material (HTM), 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene (spiro-MeOTAD), has been investigated in terms of HTM overlayer thickness. Two important parameters, soak time and spin-coating rate, are varied to control the HTM thickness. Decrease in the period of loading the spiro-MeOTAD solution on $TiO_2$ layer (soak time) leads to decrease in the HTM overlayer thickness, whereas decrease in spin-coating rate increases the HTM overlayer thickness. Photocurrent density and fill factor increase with decreasing the overlayer thickness, whereas open-circuit voltage remains almost unchanged. The improved photocurrent density is mainly ascribed to the enhanced charge transport rate, associated with the improved charge collection efficiency. Among the studied HTM overlayer thicknesses, ca. 230 nm-thick HTM overlayer demonstrates best efficiency of 4.5% at AM 1.5G one sun light intensity.

• Journal of the Korea Furniture Society
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• v.23 no.1
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• pp.75-83
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• 2012

Space dominates all the art activities human do and plays a role of providing aesthetic emotion. Architecture, sculpture, painting, and furniture, etc. these two and three dimensional works are represented in space and interpreted the role of its form, structure and function. Each area is different, but space has been studied in philosophy, physics, geometry, and mathematical studies, etc. and has been consistently interpreted and represented relating to a variety of human creative activity. Furniture is also three dimensional art being dependent on space. In the United States in 2004, I made the living room bench by applying the spatial concept at Rochester Institute of Technology. Two years later, this design was adopted by wendell Castle Collection, an American furniture company, then prototype were made and tested three times during a year, and then since 2007 as indoor benches it has been manufactured in the United States. The study's purpose is to order the process of its development based on the experience of bench production applied the spatial concept, and by analyzing the properties of spatial concept, I am planning to propose a new concept on interaction with the space and furniture for next.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.396-396
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• 2012

$TiO_2$ anatase nanotube arrays (NTAs) were grown by electrochemical anodization and followed annealing of Ti foil. Ethylene glycol/$NH_4F$-based organic electrolyte was used for electrolyte solution and using second anodization process to obtain free-standing NTAs. After obtaining NTAs, ITO film was deposited by sputtering process on bottom of NTAs. UV-curable NOA was used for attach free-standing NTAs on flexible plastic substrate (PEN). Solid state electrolyte (spiro-OMeTAD) was coated via spin-coating method on top of attached NTAs. Ag was deposited as a counter electrode. Under AM 1.5 simulated sunlight, optical characteristics of devices were investigated. In order to use flexible polymer substrate, processes have to be conducted at low temperature. In case of $TiO_2$ nano particles (NPs), however, crystallization of NPs at high temperature above $450^{\circ}C$ is required. Because NTAs were conducted high temperature annealing process before NTAs transfer to PEN, it is favorable for using PEN as flexible substrate. Fabricated flexible solid-state DSSCs make possible the preventing of liquid electrolyte corrosion and leakage, various application.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.494-498
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• 2003

The transition from aromatics to heteroaromatics is very attractive since it provides an extremely large structural variety, the chemical functionality as well as the possibilities for electronic tuning of the fullerene properties. A synthesis of heterofullerenes in macroscopic quantities is unknown however the spectrometric detection of $C_{59}B$ has been reported. The electronic structures of $C_{(60-2x)}(BN)_x$ systems, isoelectronic with $C_{60}$ have been explored by Extended Hukel, AM1 and ab initio methods. The polyhedral assembly energy are 7.7 kcal greater than $C_{60}$ when one B-N unit is substituted with C-C unit. The assembly energies are getting bigger if more B-N unit is introduced. We focus on HOMO-LUMO energy gap and the stability effects in $C_{(60-2x)}(BN)_x$ with different compositions of $(BN)_x$ moiety. The bonding properties of the substituent atoms were investigated in detail.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1495-1498
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• 2008

$TiO_2$ nanopowders were synthesized by new sol-gel combustion hybrid method using acetylene black as a fuel. The dried gels exhibited autocatalytic combustion behaviour. $TiO_2$ nanopowders with an anatase structure and a narrow size distribution were obtained at 400-600 ${^{\circ}C}$. Their crystal structures were examined by powder Xray diffraction (XRD) and their morphology and crystal size were investigated by scanning electron microscopy (SEM). The crystal size of the nanopowders was found to be in the range of 15-20 nm. $TiO_2$ powders synthesized at 500 ${^{\circ}C}$ and 600 ${^{\circ}C}$ were applied to a dye solar cell. An efficiency of 5.2% for the conversion of solar energy to electricity ($J_{sc}$ = 11.79 mA/$cm^2$, $V_{oc}$ = 0.73 V, and FF = 0.58) was obtained for an AM 1.5 irradiation (100 mW/$cm^2$) using the $TiO_2$ nanopowder synthesized by the sol-gel combustion hybrid method at 500 ${^{\circ}C}$.

• Applied Microscopy
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• v.47 no.3
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• pp.126-130
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• 2017

The dielectric relaxation characteristics of composites with different concentrations of carbon nanotubes loaded in an epoxy polymer matrix has been studied as a function of frequency over a wide range (1 Hz~10 MHz) at room temperature. Two characterization techniques were used in this work to measure and calculate the dimensionality parameters: small angle neutron scattering and impedance spectroscopy. The results obtained from both methods are in good agreement, indicating the reliability of the estimated fractal dimension, despite of the difference in the length scales accessed by the two techniques.

• Human Ecology Research
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• v.55 no.3
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• pp.303-319
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• 2017

This study explored the sandplay therapy case of a middle-aged woman having difficulty with interpersonal relationships and wanting to increase her self-identity. The goal of the therapy was to change her relationships with others by self-examination and becoming conscious of her negative animus and femininity in a free and protected space provided by sandplay therapy. Forty-five therapy sessions were held. The client exhibited her lonesomeness and fantasies by making sandtrays of a house she would like to live in, a park she would like to relax at and dreams she would like to fulfill in the initial phase of therapy (1~8, Who am I?). In the intermediate phase of therapy (9~33, Meeting myself), she displayed scenes of her negative self and breaking away from her negative self by making sandtrays of shadows, deaths, creations, a soaring scene and a disappearing alligator. In the final phase of therapy (34~45, Discovery of the real Self), she showed scenes of her meeting a positive self by making sandtrays of hope, coexistence, start, harmony and community. This study showed the effectiveness of sandplay therapy since the client' relationships with others were improved through her self-awareness by sandplay therapy in the free and protected space.

• Journal of Acupuncture Research
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• v.19 no.4
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• pp.101-111
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• 2002

Objective : In order to review the studies related to the treatment of children by aupuncture or mo ibustion Methods : We referred to a Pubmed site by using searching word of "the terms of pediatrics(for e ample child children infant baby pediatrics etc and acupuncture" Results : 40 journals with 63 papers were searched 50 papers were reported Conclusion : 1 We found 63 articles in 40 journals which were Pediatrics J Tradit chin Med Am Fam Physician Anaesthesia linical research was the most of these studies and the pattern of the rest were review or clinical conferences 3 We analy ed articles and found many articles of nocturnal enuresis asthma bronchitis postoperative vomitting constipation etc 4 The result of clinical studies represented the significant cure rate owever the cases of sensorineural hearing loss vomitting after tonsillectomy e ercise induced asthma were not 5 It was ta en to research for laser acupressure bloodletting ear acupuncture etc as well as body acupuncture in the area of pediatric acupuncture treatment as alternative therapy which was composed of the lower stimulation than adult.

• Journal of Korean Society of Transportation
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• v.11 no.1
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• pp.67-86
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• 1993

A formulation of dynamic traffic assignment between multiple origins and single destination was first introduced in 1987 by Merchant and Nemhauser, and then expanded for multiple destination in the late 1980's (Carey, 1987). Based on behavioral choice theory which provides proper demand elasticities with respect to changes in policy variables, traffic phenomena can be analysed more realistically, especially in peak periods. However, algorithms for these models are not well developed so far(working with only small toy network) and solutions of these models are not unique. In this paper, a new model is developed which keeps the simplicity of static models, but provides the sensitivity of dynamic models with changes of O-D flows over time. It can be viewed as a joint departure time and route choice model, in the given time periods(6-7, 7-8, 8-9 and 9-10 am). Standard multinomial logit model has been used for simulating the choice behavior of destination, mode, route and departure time within a framework of the incremental network assignment model. The model developed is workable in a PC 386 with 175 traffic zones and 3581 links of Seoul and tested for evaluating the exclusive use of Namsan tunnel for HOV and the left-turn prohibition. Model's performance results and their statistical significance are also presented.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.171-184
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• 2004

The silk amino acid supplementation is unknown to affect the release of several hormones related to energy production and metabolism during prolonged exercise. This study examined the effects of silk amino acid supplementation on the level of blood amino acid, energy substrates and hormones level during prolonged treadmill exercise in college taekwondo player. A prolonged treadmill test was carried out 60 min at 65% of maximal heart rate on 8 athletics. Blood samples were obtained form antecubital vein of subjects at rest bed 30 minute before test, after exercise and rest 1 hour. The subjects were supplemented silk amino acid (6,390 mg/day) fur 4 week. The silk amino acid supplementation did not produce significant changes on the levels of blood lactate, ammonia, amino acid, glucose, triglyceride, total cholesterol, HDL, LDL, seratonin and leptin at rest bed 30 minute before test, after exercise and rest 30 minute. The silk amino acid 4 week supplementation did not affect the levels of blood amino acid, energy substrates and hormones during prolonged treadmill exercise.