• 한국초전도학회:학술대회논문집
• /
• v.9
• /
• pp.322-325
• /
• 1999

We fabricated 18cm YBCO coated conductor comprising a YBCO superconducting film and CeO$_2$/YSZ/CeO$_2$ buffer films deposited on a biaxially textured Ni tape. For those film fabrications, we developed a new method, the cylindrical holder in a double chamber. This is alternative to the reel-to-reef method which is commonly tried to fabricate a long YBCO coated tape. We will discuss about the superconducting properties of the 18cm long YBCO coated tapes.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.255-255
• /
• 2006

Polymeric nanoparticles are recognized as promising drug carriers [1]. Here, novel tri-block copolymers based on poly PPDO, PCL and PEG were synthesized and employed for the formulation of reproducible polymeric nanoparticles [2]. To estimate the feasibility of the polymer to form polymeric nanoparticles, nanoparticles were prepared by co-solvent evaporation technique. Polymerization and structural features of the polymer were analyzed by different physico-chemical techniques. Existence of hydrophobic domains as a core of nanoparticles was characterized by $^{1}H-NMR$ spectroscopy, and further confirmed by fluorescence technique using pyrene as probe.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.984-986
• /
• 2006

We report efficient inverted transparent blue OLEDs (ITOED) with an hole injection layer prepared by co-evaporation of $WO_3$ with NPB, which achieved a total current efficiency of 10.7 cd/A at $20mA/cm^2$ with light emits from both ITO bottom cathode and Au top anode in about 3:1 ratio.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.966-969
• /
• 2003

Thin film capacitors with Al-Polymer-Al sandwich structure were fabricated. The bottom and top aluminium (Al) electrodes were deposited by vacuum evaporation and copper phthalocyanine (CuPc), polyaniline-emeraldine base (Pani-EB) and cobalt phthalocyanine/polyaniline - emeraldine base (CoPc /Pani-EB) blend films (which can be used as buffer hole injection layer in OLEDs) were deposited by spin coating technique. X-ray diffractograms indicated amorphous nature of the polymer films whose thicknesses were measured by capacitance and Rutherford Backscattering Spectrometry (RBS) methods. AC conduction studies revealed that the conduction mechanism responsible in these films is variable range hopping of polarons. From D.C conduction studies, it is observed that, the nature of conduction is ohmic in the lower fields and at higher fields the dominating D.C conduction is of Poole-Frenkel type.

• Proceedings of the KSME Conference
• /
• 2001.11b
• /
• pp.909-914
• /
• 2001

After burner which is main part of inert gas generator(IGG) is studied for the development of IGG. The results of many experimental equations are applied to estimate characteristics of the spray nozzle and evaporation of spray, and selected the optimum design point of after burner. The selected design point of after burner are validated experimentally through the pilot plant of after burner. The flame stability is favorable at design point(150mm), that distance from stabilizer to nozzle. The emission of $NO_x$ and CO is lower than gas turbine combustor which was used in primary combustor.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.9 no.2
• /
• pp.152-155
• /
• 1998

Laryngeal framework surgery to improve change the voice is a challenging development in phoniatric surgery. Basically two categories can be distinguished : (1) attempted medialization of the vocal fold, as for the treatment of paralytic dysphonias (2) adjustment of the vocal fold's tension of transsexuals or mutational dysphonia. Vocal pitch can be elevated by various surgical technique 1) cricothyroid approximation 2) A-P expansion of the thyroid ala 3) longitudinal incision in the cords 4) intrachondral injection of the steroid, and 5) evaporation of the cords by $CO_2$ laser. We have experienced a case of pitch elevation procedure after transsexual operation. After transsexual operation, he had received anterior commissure laryngoplasty modified from Le Jeune with no change in voice pitch(Fo=110Hz). 8 monthes later, he had received cricothyroid approximation resulting in pitch elevation(Fo=160Hz).

• Journal of environmental and Sanitary engineering
• /
• v.15 no.4
• /
• pp.91-97
• /
• 2000

The objective of this study was to evaluate the possiblity of Foodwaste and co-treatment with other waste for vermistabilization. The value of oxidation-reduction potential(Eh) of the dewaterized foodwaste by a plant of subatmospheric evaporation was a possitive(+) value indicating, but the values of pH, salinity was idicating an unfavorable condition for earthworm life. The paper mill mixing waste properties by ripening for 20days were changed into the favorable range for earthworm. The growth of earthworms in foodwaste and mixing waste of paper mill 30% was found to be 68%, 84% for the survival rate, 227%, 275% for the liveweight increasing rate, respectively. The ingestion rate of foodwaste and mixing waste of paper mill 30% indicate 0.72g/g·d, 0.81g/g·d, respectively. About 62∼75% of ingestion amount produce cast and characteristics of cast indicate pH 6.1∼6.5 organic component 34∼42%, salinity 0.35∼0.4, CEC 73∼94 me/100g, N, P, K concentration 0.8∼1.2%, 0.4∼1.6%, 0.43∼0.5% respectively. Therefore it can be evaluated that the casts are good soil condition and organic fertilizer.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.766-769
• /
• 2002

We have seen the effects of hole-injection buffer layer in organic light-emitting diodes using copper phthalocyanine(CuPc), poly(vinylcarbazole)(PVK), and Poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate)(PEDOT:PSS) in a device structure of ITO/buffer/TPD/$Alq_3$/Al. Polymer PVK and PEDOT:PSS buffer layer was made using spin casting method and the CuPc layer was made using thermal evaporation. Current-voltage characteristics, luminance-voltage characteristics and efficiency of device were measured at room temperature with a thickness variation of buffer layer. We have obtained an improvement of the external quantum efficiency by a factor of two, four, and two and half when the CuPc, PVK, and PEDOT:PSS buffer layer are used, respectively. The enhancement of the efficiency is attributed to the improved balance of holes and elelctrons due to the use of hole-injection buffer layer. The CuPc and PEDOT:PSS layer functions as a hole-injection supporter and the PVK layer as a hole-blocking one.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.5C no.5
• /
• pp.214-216
• /
• 2005

Photoreflectance (PR) has been measured to investigate the characterization of the $Al_{0.20}Ga_{0.80}As$/GaAs heterostructures. In the PR spectrum, the 'C' peak is confirmed as the carbon defect with residual impurity originating from the growth process. After annealing, binding energy is relatively weak with As evaporation being done to increase Ga. Also obtained is the electric field value according to annealing temperature ($300{\sim}800^{\circ}C$).

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.02a
• /
• pp.86-87
• /
• 2003

TiO$_2$ 박막은 높은 유전율과 우수한 화학적 안전성, 가시광선 영역에서 우수한 투과성 및 높은 굴절률을 가지고 있어 광범위한 분야에 중요한 물질로써 사용되어져 왔다. 일반적으로 TiO$_2$는 rutile, anatase, brookite의 세 가지 결정형태를 가진다. 이런 TiO$_2$ 박막을 제작하기 위해 sputtering, e-beam evaporation, sol-gel method, chemical vapor deposition(CVD) 등과 같은 물리적, 화학적인 방법이 이용되고 있다. 이러한 제조방법들 중에서 스퍼터링 방법은 박막을 형성하는 이온들의 이온에너지를 높여주어 덩어리에 가까운 성질을 가지기 때문에 조밀한 박막을 제작하는데 이용되며, 박막의 대면적 코팅과 표면 경도가 우수한 박막을 제작할 수 있는 장점을 가지고 있다. (중략)