• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.12-16
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• 2012

Purpose : In conventional PET image reconstruction, iterative reconstruction methods such as OSEM (Ordered Subsets Expectation Maximization) have now generally replaced traditional analytic methods such as filtered back-projection. This includes improvements in components of the system model geometry, fully 3D scatter and low noise randoms estimates. SharpIR algorithm is to improve PET image contrast to noise by incorporating information about the PET detector response into the 3D iterative reconstruction algorithm. The aim of this study is evaluation of SharpIR reconstruction method in PET/CT. Materials and Methods: For the measurement of detector response for the spatial resolution, a capillary tube was filled with FDG and scanned at varying distances from the iso-center (5, 10, 15, 20 cm). To measure image quality for contrast recovery, the NEMA IEC body phantom (Data Spectrum Corporation, Hillsborough, NC) with diameters of 1, 13, 17 and 22 for simulating hot and 28 and 37 mm for simulating cold lesions. A solution of 5.4 kBq/mL of $^{18}F$-FDG in water was used as a radioactive background obtaining a lesion of background ratio of 4.0. Images were reconstructed with VUE point HD and VUE point HD using SharpIR reconstruction algorithm. For the clinical evaluation, a whole body FDG scan acquired and to demonstrate contrast recovery, ROIs were drawn on a metabolic hot spot and also on a uniform region of the liver. Images were reconstructed with function of varying iteration number (1~10). Results: The result of increases axial distance from iso-center, full width at half maximum (FWHM) is also increasing in VUE point HD reconstruction image. Even showed an increasing distances constant FWHM. VUE point HD with SharpIR than VUE point HD showed improves contrast recovery in phantom and clinical study. Conclusion: By incorporating more information about the detector system response, the SharpIR algorithm improves the accuracy of underlying model used in VUE point HD. SharpIR algorithm improve spatial resolution for a line source in air, and improves contrast recovery at equivalent noise levels in phantoms and clinical studies. Therefore, SharpIR algorithm can be applied as through a longitudinal study will be useful in clinical.

• Journal of Intelligence and Information Systems
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• v.24 no.4
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• pp.51-66
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• 2018

As AI (Artificial Intelligence) technologies have been swiftly evolved, a lot of products and services are under development in various fields for better users' experience. On this technology advance, negative effects of AI technologies also have been discussed actively while there exists positive expectation on them at the same time. For instance, many social issues such as trolley dilemma and system security issues are being debated, whereas autonomous vehicles based on artificial intelligence have had attention in terms of stability increase. Therefore, it needs to check and analyse major social issues on artificial intelligence for their development and societal acceptance. In this paper, multi-categorical sentiment analysis is conducted over online public opinion on artificial intelligence after identifying the trending topics related to artificial intelligence for two years from January 2016 to December 2017, which include the event, match between Lee Sedol and AlphaGo. Using the largest web portal in South Korea, online news, news headlines and news comments were crawled. Considering the importance of trending topics, online public opinion was analysed into seven multiple sentimental categories comprised of anger, dislike, fear, happiness, neutrality, sadness, and surprise by topics, not only two simple positive or negative sentiment. As a result, it was found that the top sentiment is "happiness" in most events and yet sentiments on each keyword are different. In addition, when the research period was divided into four periods, the first half of 2016, the second half of the year, the first half of 2017, and the second half of the year, it is confirmed that the sentiment of 'anger' decreases as goes by time. Based on the results of this analysis, it is possible to grasp various topics and trends currently discussed on artificial intelligence, and it can be used to prepare countermeasures. We hope that we can improve to measure public opinion more precisely in the future by integrating empathy level of news comments.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.67-71
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• 2013

Purpose: The Change of CT exposure condition have a effect on image quality and patient exposure dose. In this study, we evaluated effect CT image quality and SUV when CT parameters (Pitch, Rotation time) were changed. Materials and Methods: Discovery Ste (GE, USA) was used as a PET/CT scanner. Using GE QA Phantom and AAPM CT Performance Phantom for evaluate Noise of CT image. Images are acquired by using 24 combinations that four stages pitch (0.562, 0.938, 1.375, 1.75:1) and six stages X-ray tube rotation time (0.5s-1.0s). PET images are acquired using 1994 NEMA PET Phantom ($^{18}F-FDG$ 5.3 kBq/mL, 2.5 min/frame). For noise test, noise are evaluated by standard deviation of each image's CT numbers. And then we used expectation noise according to change of DLP (Dose Length Product) to experimental noise ratio for index of effectiveness. For spatial resolution test, we confirmed that it is possible to identify to 1.0 mm size of the holes at the AAPM CT Performance Phantom. Finally we evaluated each 24 image's SUV. Results: Noise efficiency were 1.00, 1.03, 1.01, 0.96 and 1.00, 1.04, 1.02, 0.97 when pitch changes at the QA Phantom and AAPM Phantom. In case of X-ray tube rotation time changes, 0.99, 1.02, 1.00, 1.00, 0.99, 0.99 and 1.01, 1.01, 0.99, 1.01, 1.01, 1.01 at the QA Phantom and AAPM Phantom. We could identify 1.0 mm size of the holes all 24 images. Also, there were no significant change of SUV and all image's average SUV were 1.1. Conclusion: 1.75:1 pitch is the most effective value at the CT image evaluation according to pitch change and It doesn't affect to the spatial resolution and SUV. However, the change of rotation time doesn't affect anything. So, we recommend to use the effective pitch like 1.75:1 and adequate X-ray tube rotation time according to patient size.

• Journal of Hospice and Palliative Care
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• v.14 no.2
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• pp.81-90
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• 2011

Purpose: This study is to understand how community members perceive past life recollection and preparation for death. Methods: Using a questionnaire, we surveyed 160 adult residents of one of the districts (gu) in Seoul, Korea. Descriptive statistics were used. Results: Participants chose their 30s and 40s as the most difficult time in their lives. The most painful experience was "an illness of a family member", followed by "trouble with a spouse", and "trouble with children". As for the most difficult social experience, "sense of loss in life" was ranked the highest. Personally, the happiest time was "accomplishment of a goal", while it was "happiness through children" in family relationship and "contribution to society through my career" in social life. As for the most regrettable experience, personally "having lived without purpose" was the highest, "not meeting my parents' expectation more" in family relationship; "not providing sufficient education" in relationship with children; "not having an occupation that I wanted" in work life, and "lack of social skills" in social life. More than 87% of the surveyed showed a positive attitude about the system of the do not resuscitate (DNS) order. For a situation where participants were supposed to have an incurable disease, "I want to be notified of the true condition" and "I want to write a will and advanced directives" ranked high, receiving more than 3.1 points out of 4. Conclusion: These results demonstrate the need for death education to provide people with an opportunity to accept their regrettable experiences in the past as part of their life. Also, this study suggests the importance of writing advanced directives for people to prepare for "death with dignity" how it can help their decision to be better respected.

• The Korean Journal of Nuclear Medicine
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• v.39 no.1
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• pp.49-56
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• 2005

Purpose: Dedicated animal PET is useful equipment for the study of new PET tracer. recently, microPET R4 was installed in the Korea institute of radiology and medical science. In this study, we measured the characteristics of scanner. Materials and methods: Resolution was measured using a line source (F-18:65 ${\mu}Ci$, inner diameter: 0.5 mm). The line source was put in the axial direction and was moved from the center of field of view to outside with 1 mm interval. PET images were reconstructed using a filtered back-protection and ordered subset expectation maximization. line source (16.5 ${\mu}Ci$, 78 mm) was put on the tenter of axial direction to measure the sensitivity when the deadtime was under 1%. Images were acquired during 4 minutes respectively from center to 39 mm outward. Delayed count was subtracted from total count and then decay was corrected for the calculation of sensitivity. Noise equivalent count ratio and scatter fraction were calculated using cylindrical phantom. Results: Spatial resolution of reconstructed image using filtered back-projection was 1.86 mm(radial), 1.95 mm(tangential), 1.95 mm(axial) in the tenter of field of view, and 2.54 mm, 2.8 mm, 1.61 mm in 2 cm away from the center respectively. Sensitivity was 2.36% at the center of transaxial field of view. Scatter fraction was 20%. Maximal noise equivalent count ratio was 66.4 kcps at 242 kBq/mL. Small animal images were acquired for confirmation of performance. Conclusion: Performance characteristics of microPET R4 were similar with reported value. So this will be a useful tool for small animal imaging.

• Korean Journal of Culture and Social Issue
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• v.16 no.1
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• pp.19-41
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• 2010

This study aims to investigate how religious orientation of college students and the religious fundamentalism are related to their subjective well-being, and the interaction of religious orientations and the religious fundamentalism on their well-being. The participants were 374 college students who studies at an university located in Seoul, whose average of age were 22.54 (SD=4.79). The psychological tests used in this research included the following: I/E-R, the Religious Fundamentalism Scale, the Spiritual Well-Being Scale, Emotion Frequency Test, Satisfaction with Life Scale, Subjective Happiness Scale, Life Satisfaction Motivation Scale, and Life Satisfaction Expectancy Scale. Although religious students experienced more religious well-being than non-religious students, their subjective well-being were not higher than those of non-religious students. Results reveal that religious orientations were positively related to subjective well-being such as life satisfaction, subjective happiness, and positive emotions, as well as spiritual well-being. However, those covariance was approximately 4~6% only. Religious fundamentalism was also positively related to spiritual well-being and life satisfaction, it was negatively related to the motivation to live though. On the other hand, moderate effects of the religious fundamentalism on the relations of religious orientations to most of subjective well-being variables. Results of simple main effect analyses indicated that the students who were strongly oriented toward religion with higher religious fundamentalism showed significantly higher existential well-being, positive emotions, life satisfaction, subjective happiness, and especially their motivation and expectation for future life, whereas there were no significant differences in subjective well-being of students with lower religious fundamentalism by religious orientation. This finding suggests that some religiosity variables could affect human well-being with interactions

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.82-90
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• 2009

Statement of problem: Recently, as patients' expectation and interest for esthetics are increasing, concerns of esthetic restoration for removable dentures as well as fixed prosthodontics are also increasing. And the color stability of artificial teeth will affect a long term success rate of the denture. But the stain or discoloration of these artificial teeth as well as denture resin has caused esthetic problem. Purpose: This study was designed to evaluate the influence on color stability of artificial teeth when soy sauce, red pepper paste and coffee which many Koreans have eaten were applied. Material and methods: For artificial teeth type(Endura $Anterio^{(R)}$, Physio $Duracross^{(R)}$, Trubyte $Biotone^{(R)}$) selected for the study, 10 specimens each were soaked into individual beakers of soy sauce, red pepper paste, coffee and distilled water. And $L^*$, $a^*$, $b^*$ value were measured for evaluation of the color difference (${\Delta}E^*$) with spectrophotometer on the 1 day, 1 week, 2 weeks, 4 weeks and 8 weeks after immersion. Results: 1. ${\Delta}E^*$ value of artificial teeth which were soaked in soy sauce and coffee was various according to soaking periods. However there was significant difference between Trubyte $Biotone^{(R)}$ and Physio $Duracross^{(R)}$ in red pepper paste regardless of soaking period(P<.05). 2. Except for 8 weeks of Endura $Anterio^{(R)}$, 4 weeks and 8 weeks of Physio $Duracross^{(R)}$, artificial teeth soaked in red pepper paste regardless of the type had significant difference of ${\Delta}E^*$ value compared with other groups (P<.05). 3. $a^*$, $b^*$ value of Endura $Anterio^{(R)}$ and Trubyte $Biotone^{(R)}$ which were soaked in red pepper paste had significant difference compared with the value of other group(P<.05). Conclusion: Red pepper paste had the greatest effect on color difference of artificial tooth. Physio $Duracross^{(R)}$ showed relatively less color difference than Trubyte $Biotone^{(R)}$ and Endura $Anterio^{(R)}$. But as ${\Delta}E^*$ difference were all less than 3.3, these artificial resin teeth seemed appropriate for clinical use.

• Journal of the Korean Society of School Health
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• v.10 no.2
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• pp.241-257
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• 1997

This study identifies a basic framework to analyze specific experiences of examinees so that which nurses are better able to understand reactions of examinees and, further, to provide better nursing treatments to them. This study follows Strauss & Corbin's analysis tool (1990). This basic framework identifies the specific mental reactions in a process away from the "being tightened" state. The main factors explaining this process include the 28 following variables : anxiety, being burdened, being suppressed, lack of agency, being suffocated, term pressure, expectation pressure, grade pressure, firmness, feebleness, helping others, being disturbed, watching others, off ficiousness, staightening on, depending on, getting along with, getting out of, shooting out, giving up, being alone, devoting, bracing up, being industrious, being harassed, being distressed, troubles, and quiting. Twelve variables are factored from the above factors which include pressure, being tighened, terms, expectations, grades, will, friends, family, open-minded confrontation, close-minded confrontation, pursuing, and wandering around. The Examinees' state of being tightened is first developed, watched by others, and finally resolved causing students either to pursue (positive reactions) or to wander around (negative reactions). Based on the theoretical framework, the following sixteen hypotheses are developed : 1. Students are less tightened in the first term. 2. Students are more tightened in the second term. 3. Students with higher grades feel less tightened. 4. Students with lower grades feel more tightened. 5. Students with higher expectations feel more tightened. 6. Students with lower expectations feel less tightened. 7. Students who are less tightened confront open-mindedly. 8. Students who are higher tightened confront close-mindedly. 9. Students with a strong will confront open-mindedly. 10. Students with a weak will confront close-mindedly. 11. Students who have more sincere friends confront open-mindedly. 12. Students who have less sincere frieds confront close-mindedly. 13. Students with family support confront open-mindedly. 14. Students with little family support confront close-mindedly. 15. Students confronting open-mindedly pursue. 16. Students confronting close-mindedly wander. We identify the following four relations from the data analysis : 1. Students with average grades in their first term are more tightened from high expectations and have a tendency to wander if they have less supporting families even if they also have a strong will and sincere friends. 2. Students with low grades in their second term are less tighened because of low expectations and have a tendency to wander if they have a weak will and few sincere friends even if they have strong family support. 3. Students with high grades in their second term are more tightened with high expectations and have a tendency to pursue confrontations open-mindedly if they have supporting families and a strong will even if they have few sincere friends. 4. Students with average grades in their first term are less tightened from fewer expectations and have a tendency to pursue confrontations open-mindedly when they have more supporting families and sincere friends even if they have a weak will. A Student's degree of being tightened are affected by grades, terms, and expectations. Being tightened is resolved positively or negatively based on will, friends, and family. We conclude that will, family support, and sincere friends cause students to confront "being tightened" open-mindedly. We also conclude that practical nursing for students who are tightened have to focus on creating environments in which students are able to confront open-mindedly.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.255-261
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• 2015

Purpose: purchasing status and understanding trends of Functional progressive addtions lenses buyers', Correlation analysis of the Binocular Function value to determine ADD then can be apply sales and prescriptions. Methods: Years 2011 to 2014, 298 patients who were prescribed functional progressive lenses were analysed based on the prescription data and SPSS (Ver. 20.0) was treated using the statistics. Results: Results: The average age of our customers are $27.66{\pm}11.55$ years, average addition power is $+0.73{\pm}0.36D$, customers are using take a prescription of ADD $+0.75{\pm}0.28D$ was the highest 44.33% to 132 people. Near point of convergence of 276 people (92.62%) was mostly less than 10 cm, and near point of accommodation of 134 people (44.97%) was also below 10 cm, within 11~15 cm were 122 people (40.94%). Most of people were within normal range in terms of Near point of convergence and near point of accommodation, near point of accommodation tend to be longer than Near point of convergence. As you can see this result shows most of customers need extra help in their near point of accommodation instead of they are leak at it. FCC (Fused cross cylinder) check Value and ADD (addition power) tests showed that the value of a strong correlation (p=0.00), NPC and NPA were also p=0.001, the correlation of the NPC and ADD is p=0.003, In addition, NPA and ADD also showed a significant correlations (p=0.005). Near Point of Accommodation, negative relative accommodation, and positive relative accommodation are all significantly correlated (p=0.00). The short distance-related variables of the ADD which are NPC, NPA, Age, also appeared to side correlate significantly with each other. Conclusion: Binocular function values of the subjects were highly correlated with each other so precise examination is required. when Age young people are working at short distance, low ADD values was prescribed for solving discomfort. So, in the case of early presbyopia, accommodative insufficiency, or people feel fatigue when they often working at near although their accommodation function is normal, when functional progressive lenses are prescribed, expectation of this should be exactly notified.

• 대한공업교육학회지
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• v.44 no.1
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• pp.23-51
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• 2019

The purpose of this study was to analysis school dropout of specialized vocational high school students using phenomenological research method. The interview for the research was carried out with 10 adolescents who dropped out specialized vocational high school from December 8 to 23, 2018. According to the result of the research, 31 themes were extracted from interviews with 10 research participants. And 10 theme clusters were categorized from these. And these clusters were divided into 3 domains : 'before school dropout', 'causes & process of school dropout, feeling about school dropout', 'after school dropout' Based on the finding of the study, major conclusions of this study were as follow: First, adolescents who dropped out specialized vocational high school suffered from hard school life, disappointing lead from teachers, stereotypical lesson. And they committed misdeeds, and had psychological difficulties. Some of them kept up the good relationship with their friends, teachers, parents, some of them did not. Some of them kept up the good relationship with their friends, teachers and parents, while some of them did not. Second, they chose dropout due to various different causes. The procedures of school dropout proceeded with comparative ease. The effect of dropout prevention program is very limited. The feeling they felt at the time of school dropout varied individually. Some adolescents who dropped out specialized vocational high school were satisfied while others were stressed out, regretting their decision. Third, they lived diligently working part-time jobs or preparing General Equivalency Diploma (GED) test after dropout. They experienced positive changes in their daily lives after dropout. But sometimes they experienced various difficulties and negative changes. Most of them had their goals, and they were preparing for them. Their expectation was low that their life will succeed if they returned to school. They wanted people to understand their decision about dropout. And multiple institutions are supporting adolescents who dropped out specialized vocational high school. They need practical support : Various information, activity for career experience, counseling etc.