• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.279-279
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• 2010

한국형 헬륨 냉각 고체형 증식(Helium Cooled Solid Breeder : HCSB) 시험 블랑켓(Test Blanket Module : TBM)은 삼중수소 증식을 위해서 $Li_2TiO_3$ 및 $Li_4SiO_4$ 페블을 고려하고 있으며, 중성자 반사 재료로는 SiC가 코팅된 흑연 페블을 사용할 예정이다. $Li_2TiO_3$ 및 $Li_4SiO_4$ 페블을 제조하기 위해서는 먼저 각각의 분말 제조가 선행되어야 한다. $Li_2TiO_3$ 분말을 합성하기 위해서는 먼저 Lithium 금속염과 Isopropoxide를 용매 및 폴리머 캐리어로서의 두 가지 기능을 하는 에틸렌글리콜에 첨가한 후 가열하여 완전히 용해시킨 후 혼합 용액을 건조시켜 겔형의 전구체를 제조한다. 이를 하소한 후 결정화시켜 Titanate 분말을 얻는데 이때의 건조, 하소 및 결정화 온도의 조건에 따른 분말의 크기 및 특성이 각각 다르다. 즉 하소 온도가 $600^{\circ}C$ 미만이면 열분해된 폴리머로부터 잔유 탄소가 남게 되고, $700^{\circ}C$를 초과하면 결정화가 시작된다. 이렇게 얻어진 Titanate분말은 지르코니아 볼을 이용하여 약 24 시간 동안 볼 밀링 과정을 통해 입도분포가 좁은 미세한 Titanate 분말로 만들었다. $Li_2TiO_3$ 페블은 위의 과정에서 얻어진 미세분말에 바인더를 이용하여 페블화 시킨 후 $1200^{\circ}C$의 전기로에서 최종 소결한 것이다. 중성자 반사 재료인 흑연페블은 강도가 약하기 때문에 표면에 SiC를 수 ${\mu}m$ 코팅해서 사용할 예정이다. 선행실험으로 건식법을 이용하여 SiC 코팅을 실시했으며, 그 결과를 소개할 것이다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1D
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• pp.169-175
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• 2006

Recently, slope failures are disastrous when they occur in mountainous area adjoining highways. The accidents associated with slope failures have increased due to rapid urbanization of mountainous area. Therefore, the inspection of slope is conducted to maintain road safety as well as road function. In this study, we apply to the remedy which is comparing existent description to advanced technology using GIS. We utilize a Terrestrial LiDAR, one of the advanced method, to generate precise and complete road slope model from expert point of view. In result, we extract hazardous slope information from external measurements referring to the evaluation criteria of external slope stability. We suggest not only the database but also the method of road risk evaluation based on internet GIS.

• The Journal of Korean Medicine
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• v.36 no.4
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• pp.8-18
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• 2015

Objectives: There have been several studies evaluated effect of electroacupuncture (EA) on spasticity but most studies could not assess spasticity quantitatively because they used clinical rating scales for assessment spasticity. The objective of this study is to evaluate effect of EA on poststroke spasticity quantitatively using tendon reflex (T-reflex). Methods: 29 stroke patients with upper extremity spasticity were randomized to EA group and control group. The EA group received combined EA and rehabilitation therapy 5 times a week for 3 weeks. Acupuncture treatment was given at Jian Yu (LI 15), Qu Chi (LI 11), Shao Hai (HT 3), Wai Guan (TE 5), He Gu (LI 4), Lie Que (LU 7), Hou Xi (SI 3) of the affected side, 30 minutes of electrical stimulation with a frequency of 40/13 Hz was applied at Qu Chi (LI 11), He Gu (LI 4). The control group received only rehabilitation therapy. The efficacy of treatment was assessed using T-reflex latency and amplitude, modified Ashworth scale (MAS) of biceps brachii, brachioradialis and triceps brachii. Fugl-Meyer motor function assessment (FMA) and functional independence measure (FIM) were also measured to assess motor function and functional independence. All outcomes were measured before treatment, immediately after 3 weeks of treatment and 1 week after 3 weeks of treatment. Results: No statistically significant differences were found in outcomes including T-reflex between the study groups except for FIM values immediately after 3 weeks of treatment (p=0.037). Conclusions: These results suggest that 3 weeks of EA does not reduce poststroke upper extremity spasticity electrophysiologically and clinically. However, small sample sizes and contradictory tendency between results from T-reflex and those from MAS require cautious judgement on interpretation of the results. A larger, well-designed clinical trials for quantitative evaluation of effect of EA on poststroke spasticity will be needed.

• Journal of the Korean Ceramic Society
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• v.38 no.6
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• pp.515-521
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• 2001

출발 물질로서 L $i_2$C $O_3$, NiC $O_3$, CoC $O_3$를 사용하고 조성과 합성 온도를 변화시켜, 고온 고상법에 의하여 LiN $i_{1-y}$ $Co_{y}$ $O_2$(y=0.1, 0.3, 0.5)를 합성하였다. 합성과 시료들의 결정구조, 미세구조 그리고 전기화학적 특성을 조사하였다. 80$0^{\circ}C$와 8$50^{\circ}C$에서 제조한 L $i_{x}$N $i_{1-y}$ $Co_{y}$ $O_2$는, 삼방정계(space group: R3m)의 $\alpha$-NaFe $O_2$구조로 결정화되어 있는 층상 구조를 형성하였다. LiN $i_{1-y}$ $Co_{y}$ $O_2$(y=0.1, 0.3, 0.5)는 Co의 양이 증가함에 따라 a축과 c축의 크기가 감소하였는데, 이는 코발트 이온의 크기가 니켈 이온의 크기보다 작은데 기인하는 것이다. 그러나 c축과 a축의 크기의 비(c/a)가 증가하였음은 이차원적 구조가 잘 발달됨을 보여준다. 니켈에 대한 코발트의 치환량에 따른 리튬 이온의 삽입/추출 가역성은 코발트의 치환량이 증가하면서 증가하여 y=0.3인 LiN $i_{0.9}$ $Co_{0.1}$ $O_2$에서 대체로 우수하였고 그 이상으로 y값이 증가하면 가역성이 나빠졌다. 80$0^{\circ}C$에서 합성한 LiN $i_{0.9}$ $Co_{0.1}$ $O_2$가 가장 큰 초기 방전 용량 146 mAh/g을 나타내었으며, 싸이클링 성능도 비교적 우수하였다. 8$50^{\circ}C$에서 합성한 LiN $i_{0.9}$ $Co_{0.1}$ $O_2$와 LiN $i_{0.7}$ $Co_{0.3}$ $O_2$가 우수한 싸이클링 성능을 보였다.다. 싸이클링 성능을 보였다.다.보였다.다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.1
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• pp.19-30
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• 2007

Modeling 3D buildings is an essential process to revive the real world into a computer. There are two ways to create a 3D building model. The first method is to use the building layer of 1:1000 digital maps based on high density point data gained from airborne laser surveying. The second method is to use LiDAR point data with digital images achieved with LiDAR. In this research we tested one sheet area of 1:1000 digital map with both methods to process a 3D building model. We have developed a process, analyzed quantitatively and evaluated the efficiency, accuracy, and reality. The resulted differed depending on the buildings shape. The first method was effective on simple buildings, and the second method was effective on complicated buildings. Also, we evaluated the accuracy of the produced model. Comparing the 3D building based on LiDAR data and digital image with digital maps, the horizontal accuracy was within ${\pm}50cm$. From the above we derived a conclusion that 3D building modeling is more effective when it is based on LiDAR data and digital maps. Using produced 3D building modeling data, we will be utilized as digital contents in various fields like 3D GIS, U-City, telematics, navigation, virtual reality and games etc.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05a
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• pp.27-31
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• 2001

We fabricated organic electroluminescent(EL) devices with mixed emitting layer of poly(N-vinylcarbazole)(PVK), 2,5-bis(5'-tert-butyl-2-benzoxazoly)thiophene(BBOT), N,N'-diphenyl-N,N'-(3-methyphenyl)-1,1'-biphenyl-4, 4'-diarnine(TPD) and poly(3-hexylthiophene)(P3HT). To improve the external quantum efficiency of EL devices, we added the functional layer to the devices such as LiF insulating layer, carrier confinement layer(BBOT) and hole injection layer(CuPc). In the ITO/emitting layer/Al device, the maximum quantum efficiency at 15V was $1.88{\times}10^{-5}%$. And then, it is increased by a factor of 27 to $5.2{\times}10^{-3}%$ in ITO/CuPc/emitting layer/BBOT/LiF/Al device at 15V.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.972-975
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• 2002

Electroluminescence(EL) devices based on organic thin layers have attracted lot of interests because of their application as display. One of the problems is red material. It offered a short life and poor emission efficiency to boot. In this study, this problem can be solved by using a multi-layer device structure. Organic electroluminescent devices which are composed of organic thin multi-layer films are fabricated. The basic structure is ITO / Emitting layer / LiP / Al EL device in which Hole transport/Electron blocking PVK layer was blending. We demonstrate the enhancement of eletroluminescence (EL) from blends of poly(3-hexylthiophene) in poly(N-vinylcarvazole). The emitting layer is consisted of a host material(PVK) and a guest emitting material(P3HT). It was showed higher EL intensity and their electro-optical properties were investigated.

• Korean Journal of Acupuncture
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• v.26 no.3
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• pp.87-101
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• 2009

Objectives : LI5 and SP6 have been used with a limit in ovary-related disease. But there is few study about the history, the reason, and the mechanism. So, this study was performed to review the literatures related with Eumyangyichonghyul and find the clinical usefulness of that. Methods : 1. The authors reviewed several literatures related with the Eumyangyichonghyul and some scientific studies. 2. We investigated the history and meaning of that, and the relation between the results of scientific studies and the function of that. 3. We found the usefulness based on ancient literatures and scientific studies. Results and Conclusions : 1. Eumyangyichonghyul has been prohibition of acupuncture since had been written on "Dong In Su Hyul Chim Gu Do Gyung". 2. Eumyangyichonghyul could suppress the fetus like as it promotes the delivery. 3. The explanations of ancient literatures and the scientific studies are very similar in viewpoint of whole body mechanism.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.444-447
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• 2002

The Jig cells are fabricated in the drying room, and consisted of elemental sulfur used as a cathode active material, lithium metal used as a anode material and 1M $LiCF_{3}SO_{3}$ dissolved in TG (Tetraglyme)/DIOX (1,3-Dioxolane) used as a electrolyte. The four kinds of electrolytes with different content of TG and DIOX are prepared. The electrochemical properties of the foregoing electrolytes-based lithium sulfur batteries are analyzed by AC impedance experiments. The conductivity of four different electrolytes is investigated. The conductivity of electrolyte [1M $LiCF_3SO_3$ dissolved in TG/DIOX (50:50, vol.)] is higher than that of other three kinds of electrolytes with different volume ratio (70:30, 30:70) and single solvent (TG).

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.6
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• pp.240-245
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• 2002

In this paper, a novel optical measuring system for the measurement of nonuniform electric field was proposed. The electric field distorted by the discharges was detected through proposed optical measuring system based on the Pockets effect and Mach-Zehnder interferometer. In order to produce distorted electric field, corona discharge was generated from needle-plane electrode in air and detected by optical measuring system. This optical measuring system is constructed by He-Ne laser, single mode optical fiber, $2{\times}2$ 50/50 beam splitter, $LiNbO_3$ Pockets cell, photo detector and PC. In this system, output signal of Pockels sensor is measured by digital oscilloscope and transferred to the PC for recording and statistical processing. Through this paper, a promising possibilities of proto-type optical measuring system were evinced.