• The Korea Journal of Herbology
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• v.23 no.4
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• pp.9-19
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• 2008

Objectives: In this study the authors investigated effects of the ethanolic extract of Rhodjola Rosea(HKC) on fatigue and hypothalamic IEG expression in rat forced swimming(FS) model. Methods: Sprague-Dawley rats were administered HKC extract(25 mg/100g, p.o.) for 3 days prior to FS, some rats underwent 10 min FS and others exhaustive forced swimming(EFS). In addition, other rats were administered extract at different times after EFS over 3 consecutive days. Results: When HKC administered before 10 mins of FS, serum actate dehydrogenase(LDH) and creatine phosphokinase(CPK) activities were significantly lower than control group. When HKC administered prior to EFS, blood lactate was significantly lower versus control group. When HKC was administered after EFS, blood lactate(at 6 and 24 hours after EFS) were significantly lower and serum LDH, CPK activities(at 24 hours after EFS) were significantly lower versus control group. When HKC was administered after EFS, c-Fos positive neurons in hypothalamic periventricular area(PVA), medial part(mPVN) and anterior hypothalamic nucleus caudal part(AHC) were significantly lower at 24 hours after EFS than in control group. HSP-72 positive neuron numbers in hypothalamus were significantly lower at 24 hours after EFS than in control group. Finally, when HKC was administered prior to 10 mins FS, HIF-$1{\alpha}$ expression in the gastrocnemius muscle was significantly increased. Conclusions: These results suggest that HKC extract has an anti-fatigue effect, and it reduces neuronal cell stress responses induced by physical stress by having a beneficial effect on lactate metabolism.

• Journal of fish pathology
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• v.6 no.1
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• pp.11-20
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• 1993

To study the immune responses of the japanese eel. Anguilla japonica, fish were injected intraperitoneally with several types of Edwardsiella tarda antigen, i. e., FKC(formalin killed cells), HKC(heat killed cells) or LPS(lipopolysaccharide), and the changes of immunocytes numbers, phagocytosis and agglutination titre in the peripheral blood of the fish were investigated. The number of lymphocytes in the peripheral blood of eels were decreased until 6 hours after injection, and then were turn to normal levels after 24 hours of injection. However, the level were slightly increased and were remained after 24 hours. The number of neutrophils of FKC, HKC or LPS injected fish were the highest at 12 hours after injection and were decreased slowly after that. Three weeks after the injections, the agglutination of antibody titre of all immunized groups were reached at 128 and were remained this level thereafter. However 6 weeks after the injections, that in HKC injected fish were dropped the level up to 4. Fish were injected with LPS and the blood from the fish were bled after 12 hours. Then the blood were incubated with E. tarda. Six hours after incubation, the phagocytic index was reached the highest level, 28.3. One week after the LPS injection, the blood were again bled and incubated with E. tarda. The phagocytic index at this time was 3.9. The phagocytic indexes of the fish injected with FKC and HKC, treted as same LPS injected fish as above, were 18.8 and 10.7, respectively. The phagocytic index of the control fish was 1.2. The antibacterial activities of normal antiserum against E. tarda were shown for both FKC and LPS injected fish, but not for HKC injected fish. The RPS(relative percentage of survival) of HKC, FKC and LPS injected fish in the challenge test were 10%, 20% and 30%, respectively. These results suggest that the effect of protection of the eel which were injected with antigen were varied with the method of preparation of the antigen.

• Journal of fish pathology
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• v.5 no.2
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• pp.77-85
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• 1992

This study was carried out in order to investigate the immunosuppressive factor and immune response of color carp. The protection and serum antibody production of juvenile color carp aganist Aeromonas hydrophila were investigated on the effect of temperature differences and injected several aquatic drugs, i.e. Hydrocortisone, Oxytetracycline, Chloramphenicol and Ascorbic acid. The fish were injected intraperitoneally with 1mg/fish of HKC and FKC at three different temperature conditions as $16^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ respectively. There were induced better protection and serum antibody production in the fish which had been kept at $24^{\circ}C$ than in the fish which had been kept at $16^{\circ}C$ and $32^{\circ}C$. The FKC immunized fish were followed 24 hrs later with intraperitoneal injection of 40mg/kg body weight of Hydrocortisone, 60mg/kg body weight of Oxytetracycline. 60mg/kg body weight of Chloramphenicol and 30mg/kg body weight of Ascorbic acid, respectively. The control fish were injected PBS only. The fish given the above aquatic drugs reduced serum antibody production level and protection rate when compared to control fish. As the results, immune response of juvenile color carp immunized FKC at $24^{\circ}C$ was more effective than $16^{\circ}C$ or $32^{\circ}C$ and immune response of juvenile color carp injected several aquatic drugs which was seemed to be immunosuppressive factor.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1696_1697
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• 2009

실리콘형 다이오드가 중성자에 노출되면 소자 내부에서 변위손상 발생으로 인한 저항의 변화현상이 발생하며, 이 변화량은 피폭된 중성자의 선량과 비례관계에 있다. 단위 중성자 피폭량에 대한 소자의 저항성 변화량은 감도로 표현되며 감도의 크기는 측정하려는 용도에 적합하게 조절되어야만 활용도를 높일 수 있다. 본 연구에서는 군용 중성자 탐지소자로 활용할 중성자 탐지소자로서 다양한 구조의 핀 다이오드를 제작하고 구조에 따른 중성자 감도를 분석하여 최적의 감도를 가지는 조건을 설정하고 개별소자 형태의 반도체 소자를 제작하였다. 제작된 소자의 중성자탐지능은 측정범위내에서 우수한 선형성을 보였고 온도에 대한 의존성 시험에서 안정적인 특성을 나타내었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.942-943
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• 2016

Stereo gamma ray detection system generates a two-dimensional image of the gamma ray by using the position values and the gamma ray signal. And the device will overlap with the visible light image shows the actual distribution of the gamma-ray space. The gamma ray detection device is a stereo configuration to a motion controller for controlling the signal measurement unit and the position detection portion for detecting the detection portion and the gamma-ray signal comprising a gamma-ray detection sensor. In this paper, we developed a system operation management algorithm for each module individually configured efficiently. We confirmed the imaged and distribution information output for the gamma rays from gamma-ray irradiation test site by using these results.

• The KSFM Journal of Fluid Machinery
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• v.19 no.1
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• pp.31-36
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• 2016

Hydraulic actuator is a primary component of the hydraulic valve systems. In this study, the thrust performance of hydraulic actuator was studied with different values of viscosity of hydraulic oil and rod diameter. Numerical analysis was performed using the commercial CFD code, ANSYS with 2-way FSI(Fluid-Structure Interaction) method and $k-{\varepsilon}$ turbulent model. Results show that increase in viscosity of hydraulic oil reduces the thrust of hydraulic actuator. In order to satisfy the output required of the actuator, it is necessary to compensate for the operating pressure. The results of pressure, velocity and thrust efficiency distributions in the hydraulic actuator were graphically depicted.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.299-304
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• 2011

In this paper, we developed the semiconductor neutron radiation detector and the multi-purpose radiation detection technologies for the next generation military personal surveymeter. The PIN type semiconductor neutron detector and the prototype measure the neutron radiation dose upto 1,000cGy with ${\pm}20%$ error. It also have a good performance about the Gamma, Alpha and Beta radiation and MIL-STD-810F.

• The KSFM Journal of Fluid Machinery
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• v.18 no.2
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• pp.48-53
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• 2015

Hydraulic actuator is a primary component of the hydraulic valve systems. This paper describes a motion characteristic of hydraulic actuator with various configurations of cushion. It plays an important role in protecting the actuator from the shock when the piston reaches the end position. Numerical analyses were conducted by using commercial code, ANSYS with k-${\varepsilon}$ turbulent model. The results for pressure and velocity distributions in the hydraulic actuator with different cushion shapes were graphically depicted.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.567-574
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• 2016

This survey was conducted in 2015, following up on theed tthe occurrence of Turnip mosaic virus (TuMV) nationwide in radish and Chinese cabbage fields of 28 cities in South Korea. A total of 152 samples of Raphanus sativus and 29 samples of Brassica rapa, showing virus-like symptoms, were collected. Among these, 107 B. rapa samples and 9 B. rapa samples were positive for TuMV when analyzed by RT-PCR. The TuMV strains found in the two crops showed 99% homology in nucleotide and amino acid sequences of coat protein to each other. Furthermore, their sequences showed 99% homology to the sequences of TuMV isolates R007 (GenBank: KU140420) and R041 (GenBank: KU140421) that were collected in 2014. These results suggested TuMV isolated from radish and cabbage in 2015 were the same strain as the isolates R007 and R041 collected in 2014. A screening test was conducted using these two isolates to select TuMV-resistant B. rapa lines out of 167 B. rapa breeding lines.and identified eight lines resistant to R007 (Kenshin, 279002, 279012, 279064, 279081, MP, C-21, HKC-004) and nine lines resistant to R041 (C-26, HKC-005, 11Su-4, 11Su-5, 11Su-7, 11Su-8, Tian Jin Lv Qing Ma Ye, CNU_141193, Jing Lv 60). Our prior data indicated 4.24% difference in sequences between the two isolates and these can serve as potential tools to develop B. rapa markers to screen for resistance against TuMV strainsin breeding populations.

• Journal of Power System Engineering
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• v.20 no.6
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• pp.20-26
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• 2016

For power electronic devices, the thermal energy density per unit volume has seen a rapid increase in recent years, owing to the miniaturization and dense integration of electronic components, as well as the continuous development in performance and function. This research examined the validity and reliability of a thermal safety model for managing the heating conditions of TRIAC electronic components. Among the electronic components of a PCB, these can be considered as a heat source. Using the model, the heating conditions of TRIAC components were maintained at their design target levels in the process of developing an LMT motor drive board. In addition, the heating characteristics of the entire PCB were analyzed to verify its thermal safety. Finally, the reliability and validity of the thermal safety model for maintaining the heating conditions of the TRIAC electronic elements at adequate levels was verified using a numerical analysis method.