• 한국콘텐츠학회논문지
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• 제9권11호
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• pp.247-253
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• 2009

본 연구는 국소온열요법(Local Hyperthermia)에 사용되는 발열체(Thermo-rod)의 온도에 따른 세포성장률의 변화를 관찰하고자 한다. 연구에 사용된 발열체는 듀플렉스 스테인리스 강(Duplex Stainless Steel)을 이용하여 개발되었다. 세포성장률을 관찰하기 위하여 CPAE세포와 Osteoblast세포를 이용하였다. 각각의 세포를 well에 분주 후 3일, 6일, 9일, 12일, 15일 동안 배양만 한 군을 대조군으로 하고 well에 발열체를 식립 후 세포를 분주하여 3일 간격(3일, 6일, 9일, 12일, 15일)으로 하루 30분 유도가열을 실시하여 15일 간 배양한 군을 시험군으로 하였다. CPAE세포와 Osteoblast세포의 성장률을 관찰한 결과 두세포 모두 3일의 대조군과 시험군 모두 세포 성장률이 급격히 상승하다 6일의 대조군과 시험군 모두 급격히 감소하고 9일과 12일 그리고 15일의 대조군과 시험군의 성장률은 불규칙하게 감소하였다. 이러한 성장률 관찰 결과 두종의 세포 모두 약 $41^{\circ}C$의 온도를 가한 시험군과 온도를 가하지 않은 대조군의 차이가 없다. 따라서 CPAE세포와 Osteoblast세포는 발열체에 의한 온도(약 $41^{\circ}C$)에 영향이 없는 것으로 판단된다.

• 한국소음진동공학회논문집
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• 제26권1호
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• pp.55-62
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• 2016

Nuclear fuels are always exposed to hot temperature and high speed coolant flow during the reactor operation. Thus the fuel rod accompanies small amplitude vibration due to the turbulent flow. The random vibration causes friction between the fuel rod and the grid structure which provides the lateral supports. The friction is critical to the fuel rod fretting wear, and it degrades fuel performance when a severe wear is developed. LuGre friction model is introduced in the paper, and the performance was evaluated comparing to the classical Coulomb model. It is shown that the developed friction force considering the Coulomb friction is not enough to stop or delay the motion while the stick-slip can be simulated using LuGre friction model. Numerical solutions of the two dimensional spacer grid cell model with the modern friction are also reviewed, and it is discussed that the new friction model simulates well the nonlinear mechanism.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제34회 추계학술대회 개최
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• pp.245-251
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• 2001

A fretting wear tester is developed for experimental study on the fuel fretting problem of light water reactor. The feature of the developed tester is it can simulate the existence of gap between spring and fuel rod as well as different contacting force including the just-contact condition (0 N on the contact). Used are a servo-motor, an eccentric cylinder and lever mechanism for driving system. A spacer grid cell is constituted with four strap segments (each segment has a spring). This fretting wear tester can also be used as a fatigue tester of a spacer grid spring with the frequency of more than 10 Hz. It is required to simulate the frequency of the vibrating fuel rod due to flow-induced vibration in a reactor. In fretting wear test, up to two span-length of a fuel cladding tube can be accommodated. A specimen of cladding tube of one span-length is specially designed, which can be extended for two-span test. For .fatigue test, a device for clamping the spring fixture is installed additionally, Presently, the tester is designed for the condition of air environment and room temperature. The variation of the reciprocal distance is measured to check the stability of input force, which will be exerted to the cladding (for fretting wear. test) and the spring (for fatigue test) specimen.

• 한국표면공학회지
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• 제45권2호
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• pp.75-80
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• 2012

A sputter-sublimation source was tested for high rate deposition of protective coating of PEMFC(polymer electrolyte membrane fuel cell) with high electrical conductivity and anti-corrosion capability by DC biasing of a metal rod immersed in inductively coupled plasma. A SUS(stainless steel) tube, rod were tested for low thermal conductivity materials and copper for high thermal conductivity ones. At 10 mTorr of Ar ICP(inductively coupled plasma) with 2.4 MHz, 300 W, the surface temperature of a SUS rod reached to $1,289^{\circ}C$ with a dc bias of 150 W (-706 V, 0.21 A) in 2 mins. For 10 min of sputter-sublimation, 0.1 gr of SUS rod was sputter-sublimated which is a good evidence of a high rate deposition source. ICP is used for sputter-sublimation of a target material, for substrate pre-treatment, film quality improvement by high energy particle bombardment and reactive deposition.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.369-370
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• 2006

During demonstrations of a process conditioning spent nuclear fuels, it is necessary to transport and handle Spent fuel road cuts from Post Irradiation Examination facility to Slitting device in The hot cell. the spent fuel pellets which are highly radioactive materials are separated with its clad and are fed into the next conditioning process. For this, a spent fuel rod, 3.5 m long, is cut by 25 cm long which is suitable length for the decladding process. These rod-cuts are packed into the capsule and are moved to the ACPF(Advanced spent nuclear fuel Conditioning Process Facility). In the ACPF, Once the capsule is unloaded in the ACPF, Capsule is taken out one-by-one and installed on the decladding device. In these processes, the crushed spent fuel pellet can be scattered inside the facilities and thus it contaminate the hot cell. In this paper, we developed the specially designed transportation and storage device for spent nuclear fuel capsules.

• Journal of Korean Neurosurgical Society
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• 제40권4호
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• pp.267-272
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• 2006

Objective : There have been recent reports that mesenchymal stromal cells that are harvested from adipose tissue are able to differentiate into neurons. In the present study, we administered adipose tissue derived stem cells in rats with cerebral infarction in order to determine whether those stem cells could enhance the recovery of motor function. Methods : Cerebral infarction was induced by intraluminal occlusion of middle cerebral artery in rats. The adipose tissue-derived mesenchymal stem cells were harvested from inguinal fat pad and proliferated for 2 weeks in DMEM media. Approximately $1{\times}10^6$ cells were injected intravenously or into subdural space of the peri-lesional area. The rotor rod test was performed at preoperative state[before MCA occlusion], and 1, 2, 3, 4, 6, 8 and 10 weeks after the cell therapy. Results : The motor functions that were assessed by rotor rod test at 1 week of the cell therapy were nearly zero among the experimental groups. However, there was apparent motor function recovery after 2 weeks and 4 weeks of cell injection in intravenously treated rats and peri-lesionaly treated rats, respectively, while there was no significant improvement till 8 weeks in vehicle treated rats. Conclusion : These results demonstrate that the adipose derived stem cell treatment improves motor function recovery in rats with cerebral infarction.

• 한국토양동물학회지
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• 제3권2호
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• pp.51-57
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• 1998

A new rod-shaped endospore-forming bacterium isolated from the hindgut flora of the termite, Reticulitermes speratus kyushuenesis Morimoto is described. The isolate stained Gram positive, but the KOH test and the test for L-alanine aminopeptidase were negative. The length of a single cell varies from 2.5-9.0 $\mu $m, and the cell is about 0.5-0.7$\mu $m thick. The isolate had a high cellulolytic ability and was identified as Bacillus amyloliquefaciens.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.25.2-25
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• 2003

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.271-272
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• 2009

We fabricated a hybrid aligned film using reactive rod-like mesogen to reduce light leakage of twisted nematic(TN) cell in off-axis of the dark state. We proved that the fabricated compensation film has hybrid alignment by changing phase retardation according to polar angle. In this paper, we confirmed characteristics of compensation film through simulation results and found the matching factor of simulation results and experimental result. In result, the maximum pretilt angle of hybrid compensated film is $19^{\circ}$ which has phase retardation 0.1445.

• Environmental Engineering Research
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• 제25권2호
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• pp.238-242
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• 2020

Sediment microbial fuel cells (SMFCs) illustrated great potential for powering environmental sensors and bioremediation of sediments. In the present study, array anodes for SMFCs were fabricated with graphite rods as anode material and stainless steel plate as electric current collector to make it inconvenient to in situ settle down and not feasible for large-scale application. The results demonstrated that maximum power of 89.4 ㎼ was obtained from three graphite rods, twice of 43.3 ㎼ for two graphite rods. Electrochemical impedance spectroscopy revealed that three graphite rods resulted in anodic resistance of 61.2 Ω, relative to 76.0 Ω of two graphite rods. It was probably caused by the parallel connection of the graphite rods, as well as more biomass which could reduce the charge transfer resistance of the biofilm anode. The presently designed array configuration possesses the advantages of easy to enlarge the surface area, decrease in anodic resistance because of the parallel connection of each graphite rod, and convenience to berry into sediment by gravity. Therefore, the as prepared array node would be an effective method to fabricate large-scale SMFC and make it easy to in situ applicate in natural sediments.