• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.157-158
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• 2013

Organic solar cell was fabricated using one-pot deposition of a mixture of NiO nanoparticles, P3HT and PCBM. In the presence of NiO, the photovoltaic performance was slightly increased comparing to that of the device without NiO. When $TiO_2$ thin films with a thickness of 2~3 nm was prepared on NiO nanoparticles using atomic layer deposition, the power conversion efficiency was increased by a factor 2.5 with respect to that with bare NiO. Moreover, breakdown voltage of the film consisting of NiO, P3HT, and PCBM on indium tin oxide was increased by more than 1 V in the presence of $TiO_2$-shell on NiO nanoparticles. It is evidenced that S atoms of P3HT can be oxidized on NiO surfaces, and $TiO_2$-shell on NiO nanoparticles. It is evidenced that S atoms of P3HT can be oxidzed on NiO surfaces, and $TiO_2$ shell heavily reduced oxidation of S at oxide/P3HT interfaces. Oxidized S atoms can most likely act as carrier generation sites and recombination centers within the depletion region, decreasing breakdown voltage and performance of organic solar cells. Our result shows that fabrication of various core-shell nanostruecutres of oxides by atomic layer deposition with controlled film thickness can be of potential importance for fabricating highly efficient organic solar cells.

• Journal of Electrochemical Science and Technology
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• 제2권2호
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• pp.110-115
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• 2011

The effect of $TiO_2$ nanotube (TNT) and nanoparticle (TNP) composite photoelectrode and the role of TNT to enhance the photo conversion efficiency in dye-sensitized solar cell (DSSC) have investigated in this study. Results demonstrated that the increase of the TNT content (1-15 %) into the electron collecting TNP film increases the open-circuit potential ($V_{oc}$) and short circuit current density ($J_{sc}$). Based on the impedance analysis, the increased $V_{oc}$ was attributed to the suppressed recombination between electrode and electrolyte or dye. Photochemical analysis revealed that the increased Jsc with the increased TNT content was due to the scattering effect and the reduced electron diffusion path of TNT. The highest $J_{sc}$ (12.6 mA/$cm^2$), Voc (711 mV) and conversion efficiency (5.9%) were obtained in the composite photoelectrode with 15% TNT. However, $J_{sc}$ and $V_{oc}$ was decreased for the case of 20% TNT, which results from the significant reduction of adsorbed dye amount and the poor attachment of the film on the fluorine-doped tin oxide (FTO). Therefore, application of this composite photoelectrode is expected to be a promising approach to improve the energy conversion efficiency of DSSC.

• 한국한의학연구원논문집
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• 제12권2호통권17호
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• pp.63-73
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• 2006

In the original plant of Arisaematis Rhizomas, the features of external and internal shape of Arisaema amurense var. serratum $N_{AKAI}$ and A. amurense $_{MAXIM}$. are as follows. 1. In the external shape of original plant, Arisaema amurense var. serratum $N_{AKAI}$ has high stem, an oval-elliptic leaflet and a serrate leaf margin. But A. amurense $M_{AXIM}$ has a relatively low stem, an upside oval leaflet and no serrate leaf margin. 2. On the herbs character of original plant, Ansaema amurense var. serratum $N_{AKAI}$ is small in height and diameter, but A. amurense $M_{AXIM}$ is relatively large in height and diameter. 3. On the gathered herbs character of original plant, the section of Arisaema amurense var. serratum $N_{AKAI}$ is brightly white, easily spilt and strong scent. But the section of A. amurense $M_{AXIM}$ is thin yellowish brown, not easily spilt and weak scent. Also the grade of gathered herbs, both can be classified by diameter and external scent. 4. In the current herbs character, Korean and Sichuan Province products are irregullar shape and have no scent, Jilin Province products are regular shape. Also, Guangxi Province products are small size and concave in one side, Hebei Province products are irregular size and shape. 5. In internal shape of original plant, epidermal cell of Arisaema amurense var. serratum is very tight. With the except of micro difference in parenchyma cell of cortex, on the whole there are nearly no differences with A. amurense $M_{AXIM}$. Also, samely in the internal shape, according to collecting sites, epidermis exhibits a lot layer in curving state and secreting duct is developed and vascular bundle and exists between parenchyma cell of cortex. In the future, additional study is needed to distinguish herb and effect between same genus-degree of relatedness.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.5176-5185
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• 2014

본 연구는 국내에서 재배되고 있는 달래의 특성을 조사하여 농가의 소득증대 및 유전자원확보를 목적으로 2010년부터 2012년 5월까지 광역단위로 달래를 수집하여 특성을 조사하였다. 달래의 특성분석은 달래가 지닌 특유의향기성분을 SPME 방법으로 분석하고, 분획물의 항산화 효과와 HaCaT, HepG2, HCT116, PC3 세포를 이용한 암세포 생장 억제 효과를 보았으며, 우리나라에 자라는 달래를 지역별로 수집하여 그 성분을 분석 및 비교하였다. 그 결과 달래에서는 총 42개의 향을 함유하고 있다고 나왔고 특히 탄화수소와 유기산의 함량이 높은 것으로 나타났으며 항산화 효과와 암세포의 성장억제 효과를 확인할 수 있었다. 이러한 달래의 높은 생리활성효과를 볼 때 향후에는 우리나라 특성화작물로써 달래를 중점적으로 육성시킬 필요성이 확인되었다.

• Journal of Electrochemical Science and Technology
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• 제10권3호
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• pp.302-312
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• 2019

The voltage produced from the salinity gradient in reverse electrodialysis (RED) increases proportionally with the number of cell pairs of alternating cation and anion exchange membranes. Large-scale RED systems consisting of hundreds of cell pairs exhibit high voltage of more than 10 V, which is sufficient to utilize water electrolysis as the electrode reaction even though there is no specific strategy for minimizing the overpotential of water electrolysis. Moreover, hydrogen gas can be simultaneously obtained as surplus energy from the electrochemical reduction of water at the cathode if the RED system is equipped with proper venting and collecting facilities. Therefore, RED-driven water electrolysis system can be a promising solution not only for sustainable electric power but also for eco-friendly hydrogen production with high purity without $CO_2$ emission. The RED system in this study includes a high membrane voltage from more than 50 cells, neutral-pH water as the electrolyte, and an artificial NaCl solution as the feed water, which are more universal, economical, and eco-friendly conditions than previous studies on RED with hydrogen production. We measure the amount of hydrogen produced at maximum power of the RED system using a batch-type electrode chamber with a gas bag and evaluate the interrelation between the electric power and hydrogen energy with varied cell pairs. A hydrogen production rate of $1.1{\times}10^{-4}mol\;cm^{-2}h^{-1}$ is obtained, which is larger than previously reported values for RED system with simultaneous hydrogen production.

• Clinics in Shoulder and Elbow
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• 제15권2호
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• pp.65-72
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• 2012

목적: 세가지 기원의 줄기 세포 분화능과 면역표현형을 평가하고자 하였다. 대상 및 방법: 견봉하 점액낭과 골수, 탯줄 혈액 세 개의 군에서 세포를 채취하였다. 견봉하 점액낭과 골수는 견관절 수술 환자군에게 임상적 동의 하에 수술중 채취하였다. 각각의 채취된 세포 및 탯줄 혈액에 대하여 계대 배양을 시행하여 신경 분화군, 지방 분화군, 골 분화군을 평가하였으며 세포 표면 항체를 밝히기 위해 유동세포분석법을 이용하였다. 결과: 견봉하 점액낭 유래 세포에서는 신경분화와 지방 분화는 8예 모두 (100%)에서, 골분화는 8례 중 5예 (62.5%)에서 성공할 수 있었으며 골수 유래 세포의 경우 신경 및 지방 분화 유도한 6례 및 5예 모두 (100%) 분화에 성공하였으나 골분화 유도는 5예 중 4예 (80%)에서 얻을 수 있었다. 반면 탯줄 유래 세포 분화 연구의 경우 신경 분화 유도 67례 중 65예 (97%)에서 지방 분화 연구 54예 중 29예 (53.7%)에서 골 분화 연구 57예 중 39예 (68.4%)에서 성공할 수 있었다. 결론: 탯줄 유래 줄기세포의 분화능과 비교하였을 때 견봉하 점액낭 및 골수 유래 줄기세포의 분화능이 우수함을 알 수 있으며 이는 향후 세포 치료에 있어서 안정성 있는 치료 제공자가 될 수 있을 것으로 보이며 향후 생체 실험 연구의 참고 자료로서도 가치가 있을 것으로 보인다.

• 한국지리정보학회지
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• 제11권1호
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• pp.1-9
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• 2008

최근 토지이용 변화에 관한 다양한 연구가 진행되고 있으며, 그 중에서 셀룰라 오토마타(Cellular Automata, CA)를 이용한 연구방법이 도시성장에 많이 활용되고 있다. CA는 셀 상태가 전이규칙에 따라 새로운 시점의 상태로 변하는 연산을 반복한다. 또한 퍼지-AHP를 이용하여 정보 손실을 최소화하고, 유연한 도시성장 모델링을 유도할 수 있다. 그러나 AHP의 경우 가중치 도출까지 의사수렴 작업이 반복되어야 하는 어려움이 있다. 그리고 셀룰라 오토마타를 이용한 시뮬레이션은 많은 연산 모델링이 필요하고, 도출된 데이터 관리 및 일정 기준 시점마다 일치성을 검증하여야 한다. 이에 본 연구는 변수에 상대적 가중치를 부여하는 AHP 단계부터 셀룰라 오토마타를 이용한 도시성장 및 검증과정을 자동화하여 부산시 도시성장을 분석하고 예측하였다. 이를 통하여 도시성장 모델링의 복잡성과 반복성 문제를 개선할 수 있다. 또한 검증과정 부분을 통해 유용성 높은 모델링을 할 수 있으며, 작성된 모듈을 사용하여 이와 유사한 사례 연구에 적용할 수 있다.

• 한국임상약학회지
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• 제20권3호
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• pp.193-199
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• 2010

Tacrolimus, an immunosuppressant prescribed against graft-versus-host disease (GVHD) in patients with allogeneichematopoietic stem cell transplantation (HSCT), is affected to change its pharmacokinetic properties by various factors. For this reason, it is needed a close monitoring to adjust dosage amount in order to optimize the blood concentration of tacrolimus is located within the effective range. According to our in-house study, 62% of HSCT-patients were needed dosage-adjustment and it is necessary to optimize the current immunosuppressive regimen in clinical settings. A retrospective study was designed to evaluate the dosing regimen (converting ratio of IV:PO=1:4) of tacrolimus in HSCT patients (n=62). After collecting data from patient's profile and medical record, pharmacokinetic parameters were calculate and compared between the estimated and the actual values in the selected subjects (n=58). It was found that the bioavailabilty (BA) of oral tacrolimus was 40.5% very much different from that is known as 25%. It implies that the current protocol has a potent risk causes dose-related toxicities to the patients. Furthermore, analyses among factors demonstrated that there was no statistical significance between BA of tacrolimus and the variable factors. In the clinical perspectives, the current converting ratio of tacrolimus in patients with HSCT to be re-considered and an appropriate and optimal alternative regimen should be adopted to prevent GVHD and to increase the quality of life of patients.

• 전기학회논문지
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• 제56권12호
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• pp.2208-2213
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• 2007

In this study we have developed a hyperspectrum imaging system for highly sensitive and effective imaging analysis. An optical setup was designed using acoustic optical tunable filter (AOTF) for high sensitive hyperspectrum imaging. Light emitted by mercury lamp gets split in to diffracted and undiffracted beams while passing though AOTF. GFP transfected HEK-293 cell line was used as a model for in vitro imaging analysis. Cells were first, analyzed by fluorescence microscope followed by flow cytometric analysis. Flow cytometric analysis showed 66.31% transfection yield in GFP transfected HEK-293 cells. Various images of GFP transfected HEK-293 cell were grabbed by collecting the diffracted light using a CCD over a dynamic range of frequency of 129-171 MHz with an interval of 3 MHz. Subsequently, for in vivo image analysis of GFP transfected cells in mouse, a whole-body-imaging system was constructed. The blue light of 488 nm wavelength was obtained from a Xenon arc lamp using an appropriate filter and transmitted through an optical cable to a ring illuminator. To check the efficacy of the newly developed whole-body-imaging system, a comparative imaging analysis was performed on a normal mouse in presence and absence of Xenon arc irradiation. The developed hyperspectrum imaging analysis with AOTF showed the highest intensity of green fluorescent protein at 153 MHz of frequency and 494 nm of wavelength. However, the fluorescence intensity remained same as that of the background below 138 MHz (475 nm) and above 162 MHz (532 nm). The mouse images captured using the constructed whole-body-imaging system appeared monochromatic in absence of Xenon arc irradiation and blue when irradiated with Xenon arc lamp. Nevertheless, in either case mouse images appeared clearly.

• International Journal of Advanced Culture Technology
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• 제10권1호
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• pp.274-283
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• 2022

Korea is facing a number difficulties arising from rising housing prices. As 'housing' takes the lion's share in personal assets, many difficulties are expected to arise from fluctuating housing prices. The purpose of this study is creating housing price prediction model to prevent such risks and induce reasonable real estate purchases. This study made many attempts for understanding real estate instability and creating appropriate housing price prediction model. This study predicted and validated housing prices by using the LSTM technique - a type of Artificial Intelligence deep learning technology. LSTM is a network in which cell state and hidden state are recursively calculated in a structure which added cell state, which is conveyor belt role, to the existing RNN's hidden state. The real sale prices of apartments in autonomous districts ranging from January 2006 to December 2019 were collected through the Ministry of Land, Infrastructure, and Transport's real sale price open system and basic apartment and commercial district information were collected through the Public Data Portal and the Seoul Metropolitan City Data. The collected real sale price data were scaled based on monthly average sale price and a total of 168 data were organized by preprocessing respective data based on address. In order to predict prices, the LSTM implementation process was conducted by setting training period as 29 months (April 2015 to August 2017), validation period as 13 months (September 2017 to September 2018), and test period as 13 months (December 2018 to December 2019) according to time series data set. As a result of this study for predicting 'prices', there have been the following results. Firstly, this study obtained 76 percent of prediction similarity. We tried to design a prediction model of real estate transaction price with the LSTM Model based on AI and Bigdata. The final prediction model was created by collecting time series data, which identified the fact that 76 percent model can be made. This validated that predicting rate of return through the LSTM method can gain reliability.