• Journal of the Korean Society of Safety
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• v.31 no.5
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• pp.22-27
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• 2016

The Electrostatic Charge Prevention Technology is a core factor that highly influences the yield of Ultra High Resolution Flat Panel Display and high-integrated semiconductor manufacturing processes. The corona or x-ray ionizations are commonly used in order to eliminate static charges during manufacturing processes. To develop such a revolutionary x-ray ionizer that is free of x-ray radiation and has function to control the volume of ion formation simultaneously is a goal of this research and it absolutely overcomes the current risks of x-ray ionization. Under the International Commission on Radiological Protection, it must have a leakage radiation level that should be lower than a recommended level that is $1{\mu}Sv/hour$. In this research, the new generation of x-ray ionizer can easily control both the volume of ion formation and the leakage radiation level at the same time. In the research, the test constraints were set and the descriptions are as below; First, In order not to leak x-ray radiation while testing, the shielding box was fully installed around the test equipment area. Second, Implement the metallic Ring Electrode along a tube window and applied zero to ${\pm}8kV$ with respect to manage the positive and negative ions formation. Lastly, the ion duty ratio was able to be controlled in different test set-ups along with a free x-ray leakage through the metallic Ring Electrode. In the result of experiment, the maximum x-ray radiation leakage was $0.2{\mu}Sv/h$. These outcome is lower than the ICRP 103 recommended value, which is $1{\mu}Sv/h$. When applying voltage to the metallic ring electrode, the positive decay time was 2.18s at the distance of 300 mm and its slope was 0.272. In addition, the negative decay time was 2.1s at the distance of 300 mm and its slope was 0.262. At the distance of 200 mm, the positive decay time was 2.29s and its slope was 0.286. The negative decay time was 2.35s and its slope was 0.293. At the distance of 100 mm, the positive decay time was 2.71s and its slope was 0.338. The negative decay time was 3.07s and its slope was 0.383. According to these research, the observation was shown that these new concept of ionizer is able to minimize the leakage radiation level and to control the positive and negative ion duty ratio while ionization.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.17 no.4
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• pp.232-238
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• 2014

Purpose: This study investigated the clinical presentations of symptomatic Clostridium difficile infection (CDI) in children. Methods: We reviewed the medical records of 43 children aged <20 years who showed either positive C. difficile culture or C. difficile toxin test results between June 2010 and April 2014. Results: Of the 43 patients (mean age 6.7 years), 22 were boys. Sixteen patients (37.2%) showed both positive C. difficile culture and toxin test results. Seventeen out of 43 children (39.5%) had preexisting gastrointestinal diseases, and 26 children had other medical conditions that were risk factors for CDI. Twenty-eight children had a history of antibiotic treatment for >3 days, and the most frequently prescribed antibiotic was amoxicillin-clavulanate (35.7%). Twenty-eight patients were diagnosed with CDI despite taking probiotic supplements, most commonly Lactobacillus acidophilus (53.6%). The most common symptom was diarrhea (72.1%) at the time CDI was diagnosed. C. difficile was eradicated in 11 patients (25.6%) after treatment with oral metronidazole for 10-14 days, and in the two patients (4.6%) who required two courses of oral metronidazole. Sixteen patients (37.2%) showed clinical improvement without any treatment. Conclusion: This study showed the various clinical characteristics of CDI in children and that preexisting clinical conditions favored the development of CDI. In addition, CDI was found to occur in a number of patients even after probiotic prophylaxis given in conjunction with antibiotic therapy.

• Journal of Korean Public Health Nursing
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• v.28 no.3
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• pp.495-508
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• 2014

Purpose: This study was conducted in order to evaluate the reliability, validity, sensitivity, and specificity of the Short Form of Bobath Memorial Hospital Fall Risk Assessment Scale (BMFRAS-SF). Methods: A validation study was conducted on 207 elderly patients aged over 65 who were admitted to Bobath Memorial Hospital. Fall risk scores of BMFRAS, composed of eight subscales (age, fall history, physical activity, consciousness level, communication, fall risk factors, underlying disease, and medications) were assessed from the electronic medical record. BMFRAS-SF was derived from eight subscales of the BMFRAS representing the significance between fallers and non-fallers (fall history, physical activity, fall risk factors, underlying disease, and medications). Internal consistency reliability and interrater reliability were assessed by Cronbach's alpha and kappa coefficient. Validity was assessed by Spearman correlation analysis, factor analysis. Sensitivity, specificity, positive predictive and negative predictive values, and a receiver-operating characteristic curve (ROC) were generated. Results: Fallers had significantly higher risk scores than non-fallers in fall history, physical activity, fall risk factors, underlying disease, and medication scales. The BMFRAS-SF demonstrated acceptable Cronbach's alpha (.706) and kappa coefficients of .95. The BMFRAS-SF subscales showed good convergent validity and construct validity. The BMFRAS-SF presented good sensitivity(86.7%), specificity(67.9%), positive predictive value(42.9%) and good negative predictive value(94.8%) at a cut-off score of 5. Areas under the ROC curves were .860 for the BMFRAS and .861 for the BMFRAS-SF. Conclusion: The BMFRAS-SF was proved to be reliable and valid. It could be used for time-saving assessment and evaluation of the high risks for falls in clinical practice settings.

• Korean Journal of Head & Neck Oncology
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• v.26 no.2
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• pp.183-186
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• 2010

Purpose : Papillary thyroid carcinoma (PTC) is known for malignant tumor which has a favorable prognosis and long-term survival. Although the prognosis for patients with PTC is generally good, PTC tends to have highly metastatic property. The purpose of this study was to analyze the central compartment lymph node in papillary thyroid cancer with no lymph node metastasis clinically and to assess the significance of prophylactic node dissection. Methods : A retrospective review was carried out in 394 patients with PTC who underwent surgery for the period from January 2004 to December 2006. The positive rate of the lymph node metastasis was analyzed. The relations between the central compartment lymph nodes and the patients' age, gender, tumor size, exrathyroidal extension(ETE), multifocality, and bilaterality were comparatively analyzed in PTC patients with preoperative no lymph node metastasis. Results : The enrolled patients were 40 male and 354 female cases. The 118 cases of them were found to have cervical lymph node metastasis. The mean age was 46 years(range, 15-77years). Tumor size(p=0.000), ETE(p=0.001), multifocality(p=0.014), and bilaterality(p=0.001) were significantly related factors for cervical lymph node metastasis clinically in papillary thyroid cancer. However, age and gender were not significantly related with lymph node metastasis. Conclusion : Although no lymph node metastasis clinically, prophylactic neck node dissection can be performed to avoid risks of local recurrence and reoperation in the light of PTC nature. The pathological status and high positive rate of central compartment lymph node relate to tumor size and extrathyroidal extension. Close surveillance for nodal status is required in follow-up.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.19-33
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• 2018

Collaborative consumption was suggested as a new paradigm of consumption and business model that focuses on sharing and using resources to reduce the risks of resource depletion and environmental impact. Individual consumers carry out a role not only as users but also as providers for collaborative consumption. In the present study, the authors investigated consumers' intention to participate in collaborative consumption both as providers and users. The effects of perceived benefit of collaborative consumption, subjective norms and ease of participation on the intention to participate in collaborative consumption were analyzed. The perceptions on benefits and subjective norms were relatively high, while the perception on ease of participation was relatively low. The effects of subjective norms and ease of participation on the intention to participate in collaborative consumption were significant. The result shows that support from one's reference group and the perception on ease of participation have significant positive effects on the intent to participate in collaborative consumption. Therefore, communication strategies for developing a positive consumer attitude and a social consensus about the necessity of collaborative consumption are needed.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.127-144
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• 2005

This study is to analyze the effects of child's inner risk factors and outer risk factors intermediated by self concept on his or her resiliency at-risk. For this study, the total of 500 students in their fifth and sixth grade of elementary schools in Busan and their parents were sampled, and a measurement tool is question district court. The questionnaire for the parents measured risk factors, and the questionnaire for the students measured self-concept and about the resiliency at-risk. The SPSS for Win 12.0 and AMOS 5.0 were used to analyze the collected data. The result of this study is as follows; First, there is a significant correlation between the sub-factors of inner risk factors, which shows that the risks of students are caused not just by one of the parents but by both of them. Second, all three variables, that is, inner risk factors, self-concepts, and the resiliency at-risk, closely interact one another. The less inner risk factors of the students, the more positive their self-concept and the more the resiliency to the risk. Third, the higher the socioeconomic status (outer risk factors) and the lower the degree of risk of the family, the more positive the self-concept of the students. Fourth, the higher the socioeconomic status(outer risk factors) and the lower the degree of risk of the family, the more the resiliency to the risk.

• Korean Journal of Cognitive Science
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• v.18 no.3
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• pp.305-324
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• 2007

We surveyed the emotional images of three kinds of scientific technologies in people's mind and the perception of technologies in terms of their risks and benefits. The contents of the image and their image values were used to estimate the affects on each technology. As an affect heuristic hypothesis predicted, people perceived the technology more beneficial or riskier depending on their overall affect. In other words, those who have positive affect on the technology Perceived less risky and more beneficial than those who have negative affect. On the other hand, those who have negative affect on the technology perceived riskier and less beneficial than those who have positive affect. We also found negative relationship between the perceived risk and perceived benefit of each technology. The implications of our findings that suggest affective heuristic were discussed in terms of the measurements of affect and the necessity of communication of scientific technologies with the public.

• Journal of Navigation and Port Research
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• v.36 no.3
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• pp.261-271
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• 2012

The purpose of the present study is to empirically examine factors that affect the information security awareness and perceived information security risk of employees of port companies. In particular, in order to identify factors that affect the perceived information security risks, we investigated the relation of assets, threats, and vulnerabilities to it, using the risk analysis methodology. With A total of 252 valid questionnaires, we also performed the structural equation modeling analysis using AMOS. It was found that first, there was no meaningful relationship between the information assets and the perceived information security risk in the case of employees of port companies. Second, threats and vulnerabilities turned out to have positive influences on the perceived information security risk. Finally, there was a positive relationship not only between the information security awareness and the information security education, but also between the information security awareness and the intention of information security. However, there was no meaningful relationship between the information security concern and the information security awareness.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.633-642
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• 2010

In this study, science teachers' perception and attitude toward nanotechnology are examined through questionnaires gathered from 134 secondary science teachers. As a result, the study shows that science teachers have high perceptiveness. However, they do not understand specific information on nanotechnology correctly. Science teachers have positive attitudes toward nanotechnology and they have perceived risks of nanotechnology as well as benefits of nanotechnology. Science teachers show positive attitudes toward the application of nanotechnology, whereas they show negative attitudes toward personal information chip and nano-taste enhancer. Science teachers are exposed to nanotechnology via various sources such as TV and internet, whereas teachers rarely get information on nanotechnology-related concepts in textbooks and teaching resources. Science teachers have perceived many textbooks do not introduce enough nanotechnology-related concepts. Many teachers try to explain the nanotechnology when textbooks include nanotechnology-related concepts, whereas quite a few of teachers do not introduce the nanotechnology-related concepts in class.

• Journal of Veterinary Clinics
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• v.34 no.2
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• pp.82-86
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• 2017

We determined the risk factors for late embryonic mortality in dairy cows. We diagnosed pregnancy at 31 days and then confirmed the diagnosis at 45 days after artificial insemination (AI) via ultrasonography. The presence of an embryo with a heartbeat was the criterion for a positive pregnancy diagnosis. A diagnosis of late embryonic mortality was made when there was no positive sign of pregnancy in cows previously diagnosed as pregnant. The overall incidence of late embryonic mortality among 3,695 pregnancies was 6.9%. Logistic regression analysis revealed that herd size, AI month, synchronization protocol, and postpartum disease were important risk factors for late embryonic mortality. Herd size > 100 (odds ratio [OR]: 0.66, p < 0.05) and 50-100 lactating cows (OR: 0.63, p < 0.01) had lower risks of late embryonic mortality than herd size < 50 lactating cows. Cows inseminated during May-July had a higher risk (OR: 1.49, p < 0.05) of late embryonic mortality than cows inseminated during February-April. Cows inseminated after estrus following $PGF_{2{\alpha}}$ treatment also had a higher risk (OR: 1.77, p < 0.001) of late embryonic mortality than cows inseminated following natural estrus. Lastly, cows with postpartum disease tended to have a higher risk (OR: 1.26, p < 0.1) of late embryonic mortality than cows without postpartum disease. In conclusion, late embryonic mortality associated with the herd size, AI month, synchronization protocol, and postpartum disease in dairy cows.