• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1483-1490
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• 2021

Many studies are undertaken into nuclear power plants (NPPs) in preparation for accidents exceeding design standards. In this paper, we analyze the applicability of various wireless communication technologies as accident countermeasures in different NPP environments. In particular, a commercial wireless communication module (WCM) is investigated by measuring leakage current and packet error rate (PER), which vary depending on the intensity of incident radiation on the module, by testing at a Co-60 gamma-ray irradiation facility. The experimental results show that the WCMs continued to operate after total doses of 940 and 1097 Gy, with PERs of 3.6% and 0.8%, when exposed to irradiation dose rates of 185 and 486 Gy/h, respectively. In short, the lower irradiation dose rate decreased the performance of WCMs more than the higher dose rate. In experiments comparing the two communication protocols of request/response and one-way, the WCMs survived up to 997 and 1177 Gy, with PERs of 2% and 0%, respectively. Since the request/response protocol uses both the transmitter and the receiver, while the one-way protocol uses only the transmitter, then the electronic system on the side of the receiver is more vulnerable to radiation effects. From our experiments, the tested module is expected to be used for design-based accidents (DBAs) of "Category A" type, and has confirmed the possibility of using wireless communication systems in NPPs.

• Smart Structures and Systems
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• v.31 no.2
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• pp.183-197
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• 2023

For long-span bridges with a structural health monitoring (SHM) system, environmental temperature-driven responses are proved to be a main component in measurements. However, anomalous structural behavior may be hidden incomplicated recorded data. In order to receive reliable assessment of structural performance, it is important to study therelationship between temperature and monitoring data. This paper presents an application of the cointegration based methodology to detect anomalies that may be masked by temperature effects and then forecast the temperature-induced deflection (TID) of long-span suspension bridges. Firstly, temperature effects on girder deflection are analyzed with fieldmeasured data of a suspension bridge. Subsequently, the cointegration testing procedure is conducted. A threshold-based anomaly detection framework that eliminates the influence of environmental temperature is also proposed. The cointegrated residual series is extracted as the index to monitor anomaly events in bridges. Then, wavelet separation method is used to obtain TIDs from recorded data. Combining cointegration theory with autoregressive moving average (ARMA) model, TIDs for longspan bridges are modeled and forecasted. Finally, in-situ measurements of Xihoumen Bridge are adopted as an example to demonstrate the effectiveness of the cointegration based approach. In conclusion, the proposed method is practical for actual structures which ensures the efficient management and maintenance based on monitoring data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.11
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• pp.76-83
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• 2006

Space radiation environment for COMS is simulated by NASA AP8/AE8, JPL91 and NRL CREME models, respectively for trapped particle, solar proton and cosmic-ray. The radiation effects on electronic devices in communication payload are also estimated by using simulation results. Dose-depth curve and LET spectrum are calculated for estimating total ionizing dose(TID) effect and single event effect(SEE) respectively. Spherical sector method is applied to dose estimation at each position in the units of communication payload to consider shielding effect of platform and housing. Total ionizing dose at each position varies by 8 times through shielding effect under the same external space radiation environment.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1093-1096
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• 2003

본 논문에서는, CMOS APS Image Sensor 내에 포함되어 회로의 면적을 줄인 새롭게 제안된 CMOS Bandgap Reference Bias Generator (BGR)를 온도 및 방사능에 대한 응답을 실험하였다. 제안된 BGR 회로의 설계 목표는 V/sub DD/는 2.5V이상이고, V/sub ref/는 0.75V ± 0.5mV 마진을 가지게 하는 것이다. 제안된 BGR회로는 Level Shifter를 갖는 Differential OP-amp단과 Feedback-Loop를 가지는 Cascode Current Mirror를 사용하여 저전압에서도 동작을 가능하게 하였으며, 높은 출력저항 특성을 가지도록 하였다. 제안된 BGR회로는 하이닉스 0.18㎛ ( triple well two-poly five-metal ) CMOS 공정을 이용하여 Test Chip을 제작하였다. 온도의 변화와 Co-60 노출조건 하에서 Total ionization dose (TID) effect된 BGR회로의 V/sub ref/를 측정하여, 이를 평가하였다. 온도에 대한 반응은, 25℃ 일 때의 V/sub ref/에 대해, 각각 45 ℃에서 0.128%. 70℃에서 0.768% 변화하였다. 그리고 온도가 25℃일 때 50krad와 100krad의 방사능을 조사 하였을 경우, V/sub ref/는 각각 2.466%, 그리고 4.612% 변화하였다.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.723-737
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• 1997

본 연구의 목적은 조직유도재생술의 초기치유시에 구강양치액으로 사용되어지는 0.1% 클로르헥시딘과 0.2% 클로르헥시딘을 사용했을 경우, 양치액을 사용하지 않았을 경우의 세균감염 정도를 비교하는 것이다. 30명의 성인형 치주염에 이환되어진 사람을 대상으로 하였다. 초기치료(Scaling/Root planing/Oral hygiene instruction)를 시행한 후에 한 사람에 한 군데씩 선정하여 2급이나 3급의 치근이개부를 가지고 임상적으로 혹은 방사선학적으로 치간골내낭을 보이지 않는 치아에 통법에 따라 Gore-TexTM를 위치시켰다. 술후 5일간 항생제 (UnasynTM 375mg tablet p.o.tid)를 투여하고 차폐막을 제거할 때까지(4주 혹은 6주) 10명의 환자에게는 0.1% 클로르헥시딘을, 다른 10명의 환자에게는 0.2% 클로르헥시딘으로 구강양치를 하게 하고, 또 다른 10명의 환자에게는 구강양치액을 사용하지 않도록 하였다. 또 1주일에 한번씩 전문가구강위생술식을 실시하였다. 4주나 6주 후에 차폐막을 제거하고 주사전자현미경, 혐기성 세균배양을 이용하여 세균감염정도를 비교하였다. 1. 주사전자현미경으로 관찰시에 0.1% 클로르헥시딘을 사용했을 경우와 0.2% 클로르헥시딘을 사용했을 경우, 클로르헥시딘을 사용하지 않은 경우에 별 차이를 발견할 수 없었다. 2. 혐기성 세균배양시에 0.2% 클로르헥시딘을 사용했을 경우, 0.1%클로르헥시딘을 사용했을 경우보다 적은 수의 세균 수를 보였으나 통계적으로 유의할 만한 차이는 보이지 않았다. 클로르헥시딘을 사용하지 않은 경우에는 다른 두 경우에 비해 통계적으로 유의할 만한 차이를 보였다.(P<0.05) 3. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia를 인지한 경우에는 세 경우 모두 비슷한 비율로 발견되었다.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.1
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• pp.39-44
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• 2006

Type I diabetes (T1D) is an organ-specific autoimmune disease caused by the T cell-mediated destruction of the insulin-producing ${\beta}$ cells in the pancreatic islets. The onset of T1D is the consequence of a progressive destruction of islet ${\beta}$ cells mediated by an imbalance between effector $CD4^+$ T helper (Th)1 and regulatory $CD4^+$ Th2 cell function. Since interferon-alpha (IFN-${\alpha}$) has been known to modulate immune function and autoimmunity, we investigated whether administration of adenoviralmediated IFN-${\alpha}$ gene would inhibit the diabetic process in NOD mice. The development of diabetes was significantly inhibited by a single injection of adenoviral-mediated IFN-${\alpha}$ gene before 8 weeks of age. Next, we examined the hypothesis that Th2-type cytokines are associated with host protection against autoimmune diabetes, whereas Th1-type cytokines are associated with pathogenesis of T1D. The expression of IFN-${\alpha}$ induced increase of serum IL-4 and IL-6 (Th2 cytokines) levels and decrease of serum IL-12 and IFN-${\gamma}$ (Th1 cytokines) levels. Therefore, overexpression of IFN-${\alpha}$ by adenoviralmediated delivery provides modulation of pathogenic progression and protection of NOD mice from T1D.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.366-374
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• 2013

Anti-diabetic activities of cultured mycelia from Ganoderma applanatum are being evaluated in this study. The OGTT and 4-weeks of repeated oral efficacy tests are conducted in mice at the doses of 0 (vehicle treatment), 25, 75 and 225 mg/kg/day, respectively. In human study, the test article was administered orally every day for 8-week at a dose of 1,500 mg/kg, tid and placebo group. The blood glucose levels (BGL) at 0.5 hour after treatment are significant decreased in all treatment groups of OGTT test. In the 4-week test, BGL of 75 and 225 mg/kg/day group is continuously decreased during all treatment periods and the BGL of 25 mg/kg/day group show decreasing trends at the final week, the pancreas weight of all treatment groups are being increased, and the Langerhans-islet numbers were increased at all treatment groups with a dose-response manner. There are no test article-related abnormal signs and the fasted blood glucose (FBG), postprandial blood glucose (PPG) and HbA1c are decreased significantly after 8-week treatments. These results that the cultured mycelia from Ganoderma applanatum could decrease BGL by protecting the degeneration of Langerhans islets.

• The Journal of Korean Medicine
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• v.37 no.4
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• pp.36-44
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• 2016

Objectives: Granulocyte-colony-stimulating factor (G-CSF) mobilized bone marrow (BM)-derived hematopoietic stem cells could contribute to improvement of liver function. In addition, liver fibrosis can reportedly be prevented by the Rg 1 component of red ginseng. This study investigated the combined effect of G-CSF and red ginseng on decompensated liver cirrhosis. Methods: Four patients with decompensated liver cirrhosis were injected with G-CSF to proliferate BM stem cells for 4 days ($5{\mu}g/kg$ bid subcutaneously) and followed-up for 3 months. The patients also received red ginseng for 4 days (2 tablets tid per os). We analyzed Child-Pugh scores, Model for End-Stage Liver Disease (MELD) scores and cirrhotic complications. Results: All patients showed marked increases in White blood cell (WBC) and CD34+ cells in the peripheral blood, with a peak time of 4 days after G-CSF injection. Spleen size also increased after G-CSF injection, but not severely. At end of the study, 2 patients showed improvement in Child-Pugh scores, hepatic encephalopathy, and refractory ascites. During the clinical trial period, none of the 4 patients showed any other adverse events or deterioration of liver function. Conclusions: We conclude that G-CSF/red ginseng combination therapy is relatively effective in improving liver function and major complications of decompensated liver cirrhosis without adverse effects. Further clinical trials are warranted to assess the clinical effects of G-CSF for decompensated liver cirrhosis.

• Journal of Veterinary Clinics
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• v.20 no.4
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• pp.496-500
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• 2003

A one-year-old male Japanese Chin with anorexia, retching, dyspnea and continuous coughing was brought to the Veterinary Teaching Hospital, Chungbuk National University. Chest radiographs showed moderate regional alveolar pattern with mild interstitial patterns in the caudo-dorsal lung fields and the ill-defined mass in the perihilar area which is consistent with perihilar lymphadenopathy. Although the dog showed severe eosinophilia in the complete blood count, the serum profile values were within normal ranges. There was no indication of any parasite infestation in the direct and floatation examination of feces, skin scraping test and heartworm examination. There was no growth of bacteria and fungi in the selected media such as Mueller Hinton broth, Sabouraud Dextrose agar and Potato Dextorse agar, which were inoculated with tracheal fluid collected using endotracheal tube and cultured for 3 days. In the tracheal fluid smear, most prominent cells were eosinophils, which are a almost 80% of total cells and other cells such as leukocytes, neutrophils and ciliated colummar cells were also observed. Any parasite was also not detected in its smear. Prednisolone (PDS; 1 mg/kg, BID SC), aminophylline (10 mg/kg, TID IV) and nebulization with gentamicin (50 mg) plus saline (3 ml) were given for 1 week. At 3rd day of treatment, blood eosinophil value was return to normal range and pulmonary condition was also improved. The allergen test with serum performed during therapy was positive in the 19 index including milk, barley, tomato pomace, catfish, bonito, house dust and wool, and borderline in 10 index including wheat, house dust mites and house fly. The patient is responding well to PDS therapy. Based on these findings, a possible diagnosis of pulmonary infiltration with eosinophils was made in this dog.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1428-1435
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• 2019

The total ionizing dose (TID) and non ionizing energy loss (NIEL) effects of 100 MeV phosphorous ($P^{7+}$) and 80 MeV nitrogen ($N^{6+}$) ions on 200 GHz silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were examined in the total dose range from 1 to 100 Mrad(Si). The in-situ I-V characteristics like Gummel characteristics, excess base current (${\Delta}I_B$), net oxide trapped charge ($N_{OX}$), current gain ($h_{FE}$), avalanche multiplication (M-1), neutral base recombination (NBR) and output characteristics ($I_C-V_{CE}$) were analysed before and after irradiation. The significant degradation in device parameters was observed after $100MeV\;P^{7+}$ and $80MeV\;N^{6+}$ ion irradiation. The $100MeV\;P^{7+}$ ions create more damage in the SiGe HBT structure and in turn degrade the electrical characteristics of SiGe HBTs more when compared to $80MeV\;N^{6+}$. The SiGe HBTs irradiated up to 100 Mrad of total dose were annealed from $50^{\circ}C$ to $400^{\circ}C$ in different steps for 30 min duration in order to study the recovery of electrical characteristics. The recovery factors (RFs) are employed to analyse the contribution of room temperature and isochronal annealing in total recovery.