• Nuclear Engineering and Technology
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• v.41 no.2
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• pp.171-178
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• 2009

The rate of delayed hydride cracking (DHC), V, has been measured in cold-worked and stress-relieved Zircaloy-4 fuel cladding using the Pin-Loading Tension technique. At $250^{\circ}C$ the mean value of V from 69 specimens was $3.3({\pm}0.8)x10^{-8}$ m/s while the temperature dependence up to $275^{\circ}C$ was described by Aexp(-Q/RT), where Q is 48.3 kJ/mol. No cracking or cracking at very low rates was observed at higher temperatures. The fracture surface consisted of flat fracture with no striations. The results are compared with previous results on fuel cladding and pressure tubes.

• Journal of Environmental Impact Assessment
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• v.21 no.3
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• pp.339-352
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• 2012

Total maximum daily load have been implemented and indicated that nonpoint discharge coeffients in flow duration curve were 0.50 of Normal flow duration ($Q_{185}$) and 0.15 of low flow duration($Q_{275}$). By using SWAT, nonpoint discharge coefficients are studied with the conditions of the instream flow and the rainfall in two study areas. The nonpoint discharge coefficient average of BOD and TP for normal flows duration in 3 years are 0.32~0.36 and 0.28~0.31. For the low flow duration, the nonpoint discharge coefficient avergae of BOD and TP were 0.10~0.12 and 0.10~0.11. These are lower than the coefficients of total maximum load regulation. There are big differences between one of regulation and one of SWAT for the normal flow duration. With the consideration of rainfall condition, the nonpoint discharge coefficient of flood flow duration are influenced on the amount of rainfalls. However, the nonpoint discharge coefficients of normal flow duration and low flow duration are not effected by the rainfall condition. Since the spatial distribution and geomorphological characteristics could be considered with SWAT, the estimation of nonpoint discharge coefficient in watershed model is better method than the use of the recommended number in the regulation.

• The Journal of Internal Korean Medicine
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• v.41 no.3
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• pp.293-305
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• 2020

Purpose: This study aimed to develop a questionnaire for the diagnosis of chronic fatigue syndrome (CFS) designed based on the systematic exertion intolerance disorder (SEID) criteria, and to validate the reliability of the questionnaire. Methods: A literature search on questionnaires for CFS diagnosis was conducted to develop a SEID questionnaire (SEID-Q27), followed by a pilot survey to identify the reliability of the questionnaire. Adults (Daejeon university personnel) with a Chalder fatigue scale (CFQ) score ≥15 were invited for the survey. We commenced the survey in November 2019 with a two weeks of interval for the test and retest method. The reliability of the questionnaire was investigated in three angles: 1. Cronbach's α, 2. correlations (r) of the questions, numerical rating scale (NRS), and visual analog scale (VAS), and 3. kappa (k) analysis. Results: Among the total 275 adults registered, 55 (20%) participants with a CFQ score ≥15 were invited, and 31 (11%) [15 male, 16 female] completed the questionnaire. The total Cronbach's α was 0.944 for the test and 0.949 for the retest. The reliability (r) of questions by CFQ score (≥15, ≥18, ≥20) ranged from 0.533-0.928 (p <0.05), and the r score of the NRS and VAS were the highest in CFQ scores ≥20, at 0.933 (p<0.001). The agreement rate of the SEID-Q27 between the test and retest was 87% (kappa k=0.743). Conclusions: The SEID-Q27 seems to be reliable. Further studies are needed to measure the validity of the tool and the cutoff point.

• Journal of Gastric Cancer
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• v.14 no.1
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• pp.15-22
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• 2014

Purpose: To evaluate the prevalence of esophageal reflux-induced symptoms after gastrectomy owing to gastric cancer and assess the relationship between esophageal reflux-induced symptoms and quality of life. Materials and Methods: From January 2012 to May 2012, 332 patients were enrolled in this cross-sectional study. The patients had a history of curative resection for gastric cancer at least 6 months previously without recurrence, other malignancy, or ongoing chemotherapy. Esophageal reflux-induced symptoms were evaluated with the GerdQ questionnaire. The quality of life was evaluated with the European Organization for Research and Treatment QLQ-C30 and STO22 questionnaires. Results: Of the 332 patients, 275 had undergone subtotal gastrectomy and 57 had undergone total gastrectomy. The number of GerdQ(+) patients was 58 (21.1%) after subtotal gastrectomy, and 7 (12.3%) after total gastrectomy (P=0.127). GerdQ(+) patients showed significantly worse scores compared to those for GerdQ(-) patients in nearly all functional and symptom QLQ-C30 scales, with the difference in the mean score of global health status/quality of life and diarrhea symptoms being higher than in the minimal important difference. Additionally, in the QLQ STO22, GerdQ(+) patients had significantly worse scores in every symptom scale. The GerdQ score was negatively correlated with the global quality of life score (r=-0.170, P=0.002). Conclusions: Esophageal reflux-induced symptoms may develop at a similar rate or more frequently after subtotal gastrectomy compared to that after total gastrectomy, and decrease quality of life in gastric cancer patients. To improve quality of life after gastrectomy, new strategies are required to prevent or reduce esophageal reflux.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.273-275
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• 2002

The effect of post-weld heat treatment (PWHT) of marine structures steel was investigated at electrochemical viewpoint. In addition, slow strain rate test (SSRT) was carried out to investigate both electrochemical and mechanical properties by PWHT effect during impressed current cathodic protection. The optimum cathodic protection potential by SSRT was -770 mV(SCE). At the applied cathodic protection potential of -770 mV -850 mV(SCE), the fracture morphology was dimple pattern with ductile fracture, while it was transgranular pattern (Q.C: quasi cleavage) under -875 mV(SCE).

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.272-275
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• 1992

Recently, the digital circuit technique has had great success and gained importance in all industries. For the measurement of degree of freshness of plant and animal's tissue, many devices has been developed. But it's data was inaccurate and it had difficulty in making database because it was depend on analog circuit technique. The purpose of this paper is the development of a device based on digital circuit for measurement of freshness degree of wet fish such that its accuracy is very trustworthy and it can be measured in a short time. The device is developed by using micro-computer with some interface modules of A-D/D-A converter and digital circuit with IC modules and its effectiveness has been evaluated through two experimental results of electrical Q-value test and chemical K-value test.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.275-278
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• 2017

기존의 임베디드 기기의 하드웨어는 리눅스의 장점에도 불구하고 임베디드 기기들의 프로세서나 메모리 등의 하드웨어 자원이 Built-in 형태로 제공되어 시스템 운용 환경 변화에 맞춘 대응이 어렵다. 이러한 문제를 해결하기 위해 본 논문에서는 i.MX6Q SABRE Board for Smart Devices를 참조하여 메모리를 교체할 수 있도록 SO-DIMM을 장착하고 PCIe 이더넷을 추가한 개발보드를 만들었다. 그리고 개발보드에 추가 및 변경 된 하드웨어 디바이스를 활성화한 새로운 임베디드 시스템을 이식하는 방법을 제시한다. 구현 및 성능 분석 결과 새로운 임베디드 시스템에서 운용자는 시스템 운용 시 환경 변화에 대응하여 메모리를 바꾸어 장착할 수 있게 되었고 이로 인해 시스템의 요구사항에 따라 자원의 확정성 및 유연성이 높아짐을 확인하였다.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.275-280
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• 2022

Truffles are ectomycorrhizal fungi that belong to the genus Tuber. They exhibit symbiotic relationships, particularly with oak (Quercus spp.) and hazel (Corylus spp.) trees. We performed an inoculation using a spore suspension to synthesize mycorrhizae between European truffles, Tuber borchii and Tuber melanosporum, and an indigenous oak species, Quercus acutissima. This resulted in the formation of mycorrhizae within 2 months after inoculation. Despite having the same host plant, differences in features were observed between Tuber species, including color and mantle type. These results indicate that Q. acutissima is a suitable host plant for truffle cultivation in Korea and provide a better understanding of the mycorrhization of T. borchii and T. melanosporum.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.31-39
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• 2012

The objective of this study is to provide pollutant loads delivery ratio for flow duration in Oenam-cheon watershed, which is upstream watershed of Juam Lake. To calculate the delivery ratio by flow duration, rating curves and discharge-loads curves using measured data were established, then Flow Duration Curve(FDC) and pollutant loads delivery ratio curves were constructed. The results show that the delivery ratios for $BOD_5$ for abundant flow($Q_{95}$), ordinary flow($Q_{185}$), low flow($Q_{275}$), and drought flow($Q_{355}$) were 23.9, 12.7, 7.1, and 2.9%, respectively. The delivery ratios of same flow regime for T-N were 58.4, 31.2, 17.2 and 7.1%, respectively. While, the delivery ratios T-P were 17.3, 7.5, 3.4, and 1.1% respectively. In general, delivery ratio of high flow condition showed higher value due to the influence of nonpoint source pollution. Based on the study results, generalized equations were developed for delivery ratio and discharge per unit area, which could be used for ungaged watershed with similar pollution sources.

• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.267-275
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• 2015

This research purports to find out the characteristics of Korean students cognitive attributes and compare it with that of high-achieving countries who took TIMSS 2011 based on the Cognitive Diagnostic Theory. Based on TIMSS 2011 Science framework, nine cognitive attributes were extracted and the researcher analyzed that 216 of the TIMSS 2011 science items require these attributes. This analysis was conducted to come up with a Q-matrix. After producing the Q-matrix, multi-level IRT was used to figure out each countries' characteristics for each of the cognitive attribute. According to the study results, four attributes, such as 'Use Models,' 'Interpret Information,' 'Draw Conclusions,' and 'Evaluate and justify' were easier attributes for Korean middle school students. However, the other five attributes such as 'Recall/Recognize', 'Explain', 'Classify', 'Integrate', 'Hypothesize and Design' were considered as harder attributes compared to other countries. Korean students also considered 'Interpret Information' as the easiest attributes, and 'Explain' as the hardest attributes of all. For Korean students, those attributes considered to be easy were the easiest and hard attributes as the hardest compared to other countries, showing very extreme cases. Therefore, to give students more meaningful learning experience, it is better to use all the attributes altogether rather than use specific attributes while constructing Science curriculum or textbooks.