• Nuclear Engineering and Technology
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• 제45권5호
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• pp.625-636
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• 2013

Pressing demands of economic competitiveness, the need for large-scale deployment, minimizing the need of human intervention, and experience from the past events and incidents at operating reactors have guided the evolution and innovations in reactor technologies. Indian innovative reactor 'AHWR' is a pressure-tube type natural circulation based boiling water reactor that is designed to meet such requirements, which essentially reflect the needs of next generation reactors. The reactor employs various passive features to prevent and mitigate accidental conditions, like a slightly negative void reactivity coefficient, passive poison injection to scram the reactor in event of failure of the wired shutdown systems, a large elevated pool of water as a heat sink inside the containment, passive decay heat removal based on natural circulation and passive valves, passive ECC injection, etc. It is designed to meet the fundamental safety requirements of safe shutdown, safe decay heat removal and confinement of activity with no impact in public domain, and hence, no need for emergency planning under all conceivable scenarios. This paper examines the role of the various passive safety systems in prevention and mitigation of severe plant conditions that may arise in event of multiple failures. For the purpose of demonstration of the effectiveness of its passive features, postulated scenarios on the lines of three major severe accidents in the history of nuclear power reactors are considered, namely; the Three Mile Island (TMI), Chernobyl and Fukushima accidents. Severe plant conditions along the lines of these scenarios are postulated to the extent conceivable in the reactor under consideration and analyzed using best estimate system thermal-hydraulics code RELAP5/Mod3.2. It is found that the various passive systems incorporated enable the reactor to tolerate the postulated accident conditions without causing severe plant conditions and core degradation.

• 대한임상독성학회지
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• 제9권1호
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• pp.8-13
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• 2011

Purpose: Although glyphosate-surfactant herbicide intoxication is relatively mild toxic in humans, we encountered an atypical clinical presentation. We performed this study to understand the atypical clinical course and factors associated with severe intoxication after glyphosate ingestion. Methods: We conducted a retrospective study of 61 patients (male 43, mean age $54{\pm}18.8$ years) who were presented with glyphosate ingestion between March 1997 and March 2011. The severe intoxication group was defined as patients with systolic blood pressure less than 90 mmHg, respiratory distress needing intubation, or altered mental state. Results: Of the 61 patients, 22 patients (36.1%) had a severe clinical course, 1 patient (1.6%) had died and 1 patient (1.6%) had moribund discharge. The most common symptoms were nausea with or without vomiting which occurred in 30 patients (49.2%). Twenty-seven patients had metabolic acidosis that was the second most common medical complication. Advanced age, pH, base excess, $HCO_3$, Sat, creatinine, X-ray abnormalities and ECG abnormalities were significant factors. Hemoglobin, platelet, $pO_2$, $pCO_2$, BUN, sodium, potassium and AST levels were not different comparing the laboratory characteristics between the severe and mild intoxication groups. Conclusion: The results of this study showed that severe intoxication occurred in 22 patients (36.1%) after glyphosate intoxication. Advanced age, pH, base excess, $HCO_3$, Sat, creatinine, X-ray abnormality and ECG abnormalities were significant predictive factors for severe intoxication in patients with glyphosate surfactant herbicide poisoning.

• Journal of the Korean Wood Science and Technology
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• 제12권1호
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• pp.31-37
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• 1984

For the modification of kiln drying schedule, relations between resistance to drying Rd and the moisture content or drying times were found for 4/4, 6/4 and 8/4 green Douglas fir heartwood by the mild drying schedule and the severe drying schedule until the average moisture content was about 10 percent. The results of this study were as follows. 1. Resistance to drying of thicker lumber was higher than that of thinner lumber and resistance to drying of three different thicknesses were negligible between the mild-and the severe drying schedule. The relationships between resistance to drying and two schedules or three thicknesses of lumber were $Rd_1=1.830{\times}10^5\;M^{-2.24}$ for 4/4 lumber by the mild drying schedule, $Rd_2=1.822{\times}10^5\;M^{-2.25}$ for 4/4 lumber by the severe drying schedule, $Rd_3=2.352{\times}10^5\;M^{-2.14}$ for 6/4 lumber by the mild drying schedule, $Rd_4=3.457{\times}10^5\;M^{-2.27}$ for 6/4 lumber by the severe drying schedule, $Rd_5=1.317{\times}10^6\;M^{-2.56}$ for 8/4 lumber by the mild drying schedule, $Rd_6=8.267{\times}10^5\;M^{-2.40}$ for 8/4 lumber by the severe drying schedule. 2. Thinner lumber exhibited lower level of moisture content and shorter drying time required at intersection point between the moisture content and resistance to drying as a function of drying time than those of thicker lumber. Drying time of mild drying was longer than that of severe drying and similar to the level of moisture content at intersection point.

• 사상체질의학회지
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• 제27권3호
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• pp.307-317
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• 2015

Objectives The purpose of study was to identify cancer related symptoms of Sasang Constitution based on the classic of Sasang Constitutional Medicine (SCM). Methods The bibliographical study was performed with "Dongyisoosebowon-Shinchukbon(東醫壽世保元 辛丑本)", Dongyisoosebowon-Sasangchobongwon(東醫壽世保元 四象草本券), "Cancer", and several review articles. The perspective on severe illness in SCM was investigated. And 'the critical state' of constitutional symptoms based on "Dongyisoosebowon" was identified as cancer related symptoms. Results and Conclusions The perspective on severe illness of SCM was focused on the human being itself, compared with symptom based traditional Chinese medicine. The preservation of requisite energy (保命之主) was a vital factor of longevity to maintain healthy status and the classification of severity of disease. And critical state was an important indicator to control severe illness. Regarding cancer related symptoms in SCM, Janggwol(臟厥), Eumsung-gyeokyang(陰盛隔陽證), Janggyeol(藏結證) of Soeumin symptoms, Hwangdal(黃疸), Haso(下消), Eumheo-oyel(陰虛午熱證), Gochang, Tohyul(吐血) of Soyangin's symptoms, Joyeol(燥熱證), Bokchang-bujong(腹脹浮腫) of Taeeumin's symptoms, and Eolgyek of Taeyangin's symptoms could be shown the association with cancer. According to the prognosis on disease severity, regimens of daily life, behavior modifications as well as medications were also emphasized with great importance to control severe illness in SCM. These holistic approach for controlling severe illness in SCM could lead to the improvement of treatment outcome.

• Tuberculosis and Respiratory Diseases
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• 제70권1호
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• pp.51-57
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• 2011

Background: Early recognition and treatment of sepsis would improve patients' outcome. But it is difficult to distinguish between sepsis and non-infectious conditions in the acute phase of clinical deterioration. We studied serum level of procalcitonin (PCT) as a method to diagnose and to evaluate sepsis. Methods: Between 1 March 2009 and 30 September 2009, 178 patients had their serum PCT tested during their clinical deterioration in the medical intensive care unit. These laboratories were evaluated, on a retrospective basis. We classified their clinical status as non-infection, local infection, sepsis, severe sepsis, and septic shock. Then, we compared their clinical status with level of PCT. Results: The number of clinical status is as follows: 18 non-infection, 33 local infection, 39 sepsis, 26 severe sepsis, and 62 septic shock patients. PCT level of non-septic group (non-infection and local infection) and septic group (sepsis, severe sepsis, septic shock) was $0.36{\pm}0.57$ ng/mL and $18.09{\pm}36.53$ ng/mL (p<0.001), respectively. Area under the curve for diagnosis of sepsis using cut-off value of PCT >0.5 ng/mL was 0.841 (p<0.001). Level of PCT as clinical status was statistically different between severe sepsis and septic shock ($^*severe$ sepsis; $4.53{\pm}6.15$ ng/mL, $^*septic$ shock $34.26{\pm}47.10$ ng/mL, $^*p$ <0.001). Conclusion: Level of PCT at clinical deterioration showed diagnostic power for septic condition. The level of PCT was statistically different between severe sepsis and septic shock.

• 대한족부족관절학회지
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• 제18권4호
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• pp.173-177
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• 2014

Purpose: The purpose of this study is to evaluate the characteristics of hallux valgus with severe hallux valgus angle (HVA) and moderate intermetatarsal angle (IMA) after proximal chevron osteotomy. Materials and Methods: Between January 2008 and December 2010, 41 patients (48 feet) were treated with proximal chevron osteotomy and distal soft tissue procedure for symptomatic severe hallux valgus deformity ($HVA{\geq}40^{\circ}$). Patients were divided into two groups, group M (IMA< $18^{\circ}$) and group S ($IMA{\geq}18^{\circ}$). Mean age of patients was 55.7 years (34~70 years) in group M and 60.0 years (44~78 years) in group S. Mean duration of follow-up was 20.4 months (12~41 months) in group M and 18.5 months (12~35 months) in group S. Radiographic parameters, including HVA, IMA, sesamoid position, metatarsus adductus angle (MAA), and distal metatarsal articular angle (DMAA), were compared between groups. Clinical results were assessed using American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS). Recurrence rate at the last follow-up was compared between group M and group S. Results: Preoperative HVA and grade of sesamoid position did not differ between the groups. However, immediate postoperative HVA and grade of sesamoid position were significantly larger in group M. Preoperative MAA and DMAA were significantly larger in group M. No significant difference in AOFAS score and VAS was observed between the groups at the last follow-up. Ten of the 27 feet (37.0%) in group M and two of the 21 feet (9.5%) in group S showed hallux valgus recurrence at the last follow-up. Group M showed a significantly higher recurrence rate than group S. Conclusion: Recurrence rate for severe hallux valgus with moderate IMA is higher than that of severe hallux valgus with severe IMA.

• 대한임상독성학회지
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• 제17권2호
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• pp.94-101
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• 2019

Purpose: This study examined the clinical characteristics of severe elderly poisoning patients to determine the factors that can prevent them. Methods: Data were collected from patients over 65 years of age presenting to the emergency center with poisoning from 2013 to 2018. Their medical records were analyzed retrospectively, and patients with a poisoning severity score of three or more were defined as the severe poisoning group. The risk factors were evaluated by univariate and multivariate analysis. Results: This study analyzed 292 patients, of whom 37 (12.7%) belonged to the severe poisoning group. The severe poisoning group showed a significantly higher association with pesticide poisoning and intentional suicide attempts. Loneliness and somatization were the cause of the suicidal ideas. No significant differences in age, sex, drinking, ingestion time, poisonous materials other than pesticides, and neuropsychological consultation were observed between the two groups. Conclusion: The severe elderly poisoning patients were the result of intentional poisoning for suicide. Loneliness and somatization were the most influential causes of suicidal poisoning. Therefore, psychiatric screening and frequent medical treatment for elderly people are required to prevent severe poisoning in elderly patients.

• Journal of Chest Surgery
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• 제52권1호
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• pp.16-24
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• 2019

Background: Optimal graft selection for coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) dysfunction remains debatable. We report an analysis of our experiences of isolated CABG in patients with severe LV dysfunction and the impact of graft strategy on long-term outcomes. Methods: We analyzed 209 patients with severe LV dysfunction (ejection fraction [EF] <30%) who underwent primary isolated CABG. Of these, 169 were revascularized with a bilateral internal thoracic arterial (ITA) graft (BITA group) and 40 were revascularized with a single ITA graft (SITA group). The mean follow-up duration was $22{\pm}32$ months. Results: There were 18 early deaths (8.6%). Overall survival at 5 years was 66.7%. The rate of freedom from cardiac-related death at 5 years was 74.1%, and was significantly higher in patients who underwent off-pump CABG (p=0.005) and in the BITA group (p=0.023). Multivariate analysis demonstrated that old age (hazard ratio [HR], 2.548; 95% confidence interval [CI], 1.134-5.762; p=0.024), off-pump CABG (HR, 0.245; 95% CI, 0.090-0.661; p=0.006), and BITA grafts (HR, 0.333; 95% CI, 0.146-0.757; p=0.009) were correlated with cardiac mortality. Conclusion: CABG in patients with severe LV dysfunction (EF <30%) showed reasonable long-term outcomes. The rate of freedom from cardiac-related death was significantly higher in patients who underwent off-pump CABG and in the BITA group. Off-pump BITA grafting strategies can be accepted as a viable primary option in patients with severe LV dysfunction if performed by an experienced surgeon.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.77-90
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• 2021

This study aimed to assess the impact of abnormal climate events on the production of Italian ryegrass (IRG), such as autumn low-temperature, severe winter cold and spring droughts in the central inland, southern inland and southern coastal regions. Seasonal climatic variables, including temperature, precipitation, wind speed, relative humidity, and sunshine duration, were used to set the abnormal climate events using principal component analysis, and the abnormal climate events were distinguished from normal using Euclidean-distance cluster analysis. Furthermore, to estimate the impact caused by abnormal climate events, the dry matter yield (DMY) of IRG between abnormal and normal climate events was compared using a t-test with 5% significance level. As a result, the impact to the DMY of IRG by abnormal climate events in the central inland of Korea was significantly large in order of severe winter cold, spring drought, and autumn low-temperature. In the southern inland regions, severe winter cold was also the most serious abnormal event. These results indicate that the severe cold is critical to IRG in inland regions. Meanwhile, in the southern coastal regions, where severe cold weather is rare, the spring drought was the most serious abnormal climate event. In particular, since 2005, the frequency of spring droughts has tended to increase. In consideration of the trend and frequency of spring drought events, it is likely that drought becomes a NEW NORMAL during spring in Korea. This study was carried out to assess the impact of seasonal abnormal climate events on the DMY of IRG, and it can be helpful to make a guideline for its vulnerability.

• Nuclear Engineering and Technology
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• 제54권2호
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• pp.579-588
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• 2022

In order to meet the needs of domestic reactor severe accident analysis program, a MIDAC (Module Invessel Degraded severe accident Analysis Code) is developed and maintained by Xi'an Jiaotong University. As the accuracy of the calculation results of the analysis program is of great significance for the formulation of severe accident mitigation measures, the article select three experiments to evaluate the updated severe accident models of MIDAC. Among them, QUENCH-06 is the international standard No.45, QUENCH-16 is a test for the analysis of air oxidation, and FROMA is an out-of-pile fuel rod melting experiment recently carried out by Xi'an Jiaotong University. The heating and melting model with lumped parameter method and the steam oxidation model with Cathcart-Pawel and Volchek-Zvonarev correlations combination in MIDAC could better meet the needs of severe accident analysis. Although the influence of nitrogen still need to be further improved, the air oxidation model with NUREG still has the ability to provide guiding significance for engineering practice.