• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.37-43
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• 2013

Purpose: PET/CT scan using the SUV (Standardized Uptake Value) of radiopharmaceutical uptake in organs and tissues as an objective indicator makes it possible to analyze physiological and chemical reactions of human organs. This study analyzes the change of the SUV uptake in accordance with the way how PET/CT patients take a rest after the injection of $^{18}F-FDG$ (Fluororo-deoxyglucose). And also subjective satisfaction is assessed listening to music while taking a rest. Materials and Methods: From April 2011 until February 2013, Among the Primary cancer patients who admitted to the Catholic Medical Center (Seoul & Bucheon St. Mary's Hospital) and scanned $^{18}F-FDG$ PET/CT and also received care through the tracking test (mean age $55.61{\pm}12.41$ years, 108 people, 48 men and 60 women) were selected. The patients were divided into two groups. The first group (A: basal study) is requested to take a rest in bed quietly after the injection. However the second one (B: follow up study) is requested to listen to the music while taking a rest. And then SUV analysis was performed respectively. At the end of the scan, ROI (Region Of Interest) were set from the center of the liver (right lobe) and 3 spots of the brain (frontal, temporal, and occipital lobes). And the SUV was calculated. To identify the correlation among those ROIs, paired t-test was performed using SPSS software (Version 12.0K for windows, P>0.05). Also, after the PET/CT scan the satisfaction study was conducted of all the patients. 1:1 questionnaire survey was performed, and that questionnaire was made using the Likert 5-point scale. By utilizing those questionnaires, the analysis about simple frequency, percentage, average, and standard deviation was performed. Results: The SUV change of the 4 designated ROIs in accordance with listening to music was not statistically significant. (Frontal lobe P-value=0.611, Occipital lobe P-value=0.499, Temporal lobe P-value=0.717, Liver P-value=0.334: P-value>0.05) And the satisfaction study indicated that group B was appear to be 0.42 points (5 basis points) higher than group A. It showed that patients are more satisfied in group B than group A. Conclusion: when performing PET/CT scan using $^{18}F-FDG$, listening to music after the injection of the radiopharmaceuticals does not affect the SUV but given the state of the psychological comfort that may increase the patient's satisfaction.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.44-47
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• 2013

Purpose: There are several methods of measuring SUV in PET/CT imaging including $SUV_{bw}$ which uses the body weight, $SUV_{bsa}$ which that uses body surface area and $SUV_{lbm}$ which uses lean body mass. Currently, Seoul National University Hospital uses $SUV_{bw}$ method which minimizes the variability. In this study, we compared and analyzed the correlation between $SUV_{bw}$ and $SUV_{bsa}$ according to patients' body mass index. Materials and Methods: Using Biograph mCT40 (Siemens, Germany), we conducted $^{18}F-FDG$ PET/CT imaging on 70 patients (41 males, 29 females; ages $58.04{\pm}12.44$). We classified the patients as underweight (BMI<20), normal weight (20$${\leq_-}$$BMI<25), overweight (25$${\leq_-}$$BMI<30), obese (30$${\leq_-}$$BMI<35) and severely obese (35$${\leq_-}$$BMI) according to the patient's sex, age and BIM. Then, bone, liver and lungs were set as ROI for calculation of maximum values of $SUV_{bw}$ and $SUV_{bsa}$, through Syngo.via VA11A analysis program. Results: Comparing the five groups divided according to the BMI by the standard differences between $SUV_{bw}$ to $SUV_{bsa}$, $SUV_{max}$ was measured to be $0.66{\pm}0.15$, $0.78{\pm}0.35$, $0.77{\pm}0.21$, $1.00{\pm}0.44$, $1.53{\pm}0.38$ for bones in underweight, normal weight, overweight, obese and severely obese groups, respectively. For liver, values of $SUV_{max}$ were $1.64{\pm}0.16$, $2.06{\pm}0.34$, $2.19{\pm}0.21$, $2.52{\pm}0.21$ and $2.74{\pm}0.40$ in the same order. And for lung, values of $SUV_{max}$ were $0.69{\pm}0.33$, $0.54{\pm}0.17$, $0.62{\pm}0.23$, $0.83{\pm0.29}$, $1.03{\pm}0.30$. Conclusion: By comparing and analyzing the differences between $SUV_{bw}$ and $SUV_{bsa}$ in this study, it was found that the differences between $SUV_{bw}$ and $SUV_{bsa}$ increased as patient's BMI increased. Thus, there is room for error in the values of SUV depending on the methods of calculations, and appropriate methods must be applied according to the circumstances in clinical settings.

• Geophysics and Geophysical Exploration
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• v.19 no.1
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• pp.1-10
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• 2016

The hypocenter distribution of microseismic events generated by hydraulic fracturing for shale gas development provides essential information for understanding characteristics of fracture network. In this study, we evaluate how inaccurate velocity models influence the inversion results of two widely used location programs, hypoellipse and hypoDD, which are developed based on an iterative linear inversion. We assume that 98 stations are densely located inside the circle with a radius of 4 km and 5 artificial hypocenter sets (S0 ~ S4) are located from the center of the network to the south with 1 km interval. Each hypocenter set contains 25 events placed on the plane. To quantify accuracies of the inversion results, we defined 6 parameters: difference between average hypocenters of assumed and inverted locations, $d_1$; ratio of assumed and inverted areas estimated by hypocenters, r; difference between dip of the reference plane and the best fitting plane for determined hypocenters, ${\theta}$; difference between strike of the reference plane and the best fitting plane for determined hypocenters, ${\phi}$; root-mean-square distance between hypocenters and the best fitting plane, $d_2$; root-mean-square error in horizontal direction on the best fitting plane, $d_3$. Synthetic travel times are calculated for the reference model having 1D layered structure and the inaccurate velocity model for the inversion is constructed by using normal distribution with standard deviations of 0.1, 0.2, and 0.3 km/s, respectively, with respect to the reference model. The parameters $d_1$, r, ${\theta}$, and $d_2$ show positive correlation with the level of velocity perturbations, but the others are not sensitive to the perturbations except S4, which is located at the outer boundary of the network. In cases of S0, S1, S2, and S3, hypoellipse and hypoDD provide similar results for $d_1$. However, for other parameters, hypoDD shows much better results and errors of locations can be reduced by about several meters regardless of the level of perturbations. In light of the purpose to understand the characteristics of hydraulic fracturing, $1{\sigma}$ error of velocity structure should be under 0.2 km/s in hypoellipse and 0.3 km/s in hypoDD.

• Sijohaknonchong
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• v.22
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• pp.195-223
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• 2005

The Younsijo is a stream of Korean poem. not simply an aggregate of stanzas, but an organic structure. Younsijo was an appeared in the 16th century. The 16th century was focused on the literature of Sadaebu (noble family, 사대부). And the make an appearance is Danhyungsijo (simply-sijo, 단형시조), Yonsijo and Kasa(가사). In that case, a social stratum is why does singing each other form. The 16th century set metaphysics(성리학) as the national ideology. Metaphysics became most prevalent at the end of the 16th century. Yonsijo also appreared during the 16th century and was closeiy related to the idea of metaphysics. Both Younsijo and metaphysics were formulated by noble family, The Yonsijo was Formed in 16th century. And the 17th century was succession. The Yonsijo in 16th century is devide to Kanghosijo (강호시조) and Hunminsijo (훈민시조). Also, Kanghosijo is devide to Youkgaline Younsijo (육가계 연시조) and Sasigaline Yonsijo (사시가계 연시조). Hunminsijo used an expressive on the order of Oryoun(오륜). Therefore, this study is forced on , , and . These things, all of the end of the utility. This paper deals with Danhyungsijo and Kasa with main emphasis on works of Songgang(송강) Jungcheol(정철). The reason for dealing one writer's works is the discussion needs consistent standard. In analyzing Songgang's Danhyungsijo, Younsijoand and Kasa, one would discern the differences among three. As a result, one could conclude that both Danhyungsijo and Kasa mainly projects individual's emotional esthetic feeling, particularly, Danhyungsijo for emotional implication, and for in-depth emotional revealing. Younsijo were chosen as it supplements the shortcoming of Sijo(as it consists of three-line only) to effectively contain the ideas of metaphysics.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.104-111
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• 2009

Purpose: Osteocalcin is also known as the bone gamma-carboxyglutamic acid (Gla) protein (BGP), is noncollagenous bone protein synthesized by osteoblasts. Serum concentrations of Osteocalcin have been used as a biochemical marker of bone turnover. The reference intervals of Osteocalcin is categorized by kit corporation according to the age. However, each laboratory should establish its own reference intervals. In this study, the variation in the serum Osteocalcin level were used to find actual standard age-specific Osteocalcin reference intervals. Materials and Methods: We have selected 864 healthy females aged 20~80 years who visited a health promotion center between Aug. 2007 and Sep. 2008. The Osteocalcin IRMA Kit (OSTEO-RIACT, CIS Bio international, Gif-sur-Yvette, France) was used for the quantification. Each results were analyzed with the SPSS 12.0 statistical software. Results: The analyzed reference intervals of Osteocalcin by using Hoffmann method are from 8.8~39.4 ng/mL to 6.3~28.8 ng/mL for the case of the age from 20 to 30, from 7.7~31.9 ng/mL to 5.9~17.4 ng/mL for the case of the age from 31 to 40, and from 8.0~36.0 ng/mL to 5.5~20.1 ng/mL for the case of the age from 41 to 50, and from 8.0~50.5 ng/mL to 6.7~27.0 ng/mL for the case of the age from 51 to 60, and from 12.9~55.9 ng/mL to 7.5~27.5 ng/mL for the case of the age from 61 to 80. Reference intervals of Osteocalcin were not in agreement with those recommended by the manufacturers. Conclusions: Osteocalcin is used as an indication of metabolic bone diseases. So in our study we wanted to provide reference intervals of Osteocalcin that can be useful to a clinical decisions. Also, previous reference intervals should not be re-used and new intervals should be set by continuous analyzing.

• Korean Security Journal
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• no.11
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• pp.21-36
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• 2006

This study aims to grasp the general conditions regarding university students in security related majors in Korea. Followings will be covered here: what motivated them to choose those majors, how much are they satisfied with major curriculum course after matriculation, whether they got jobs through the education, what is their consciousness on their majors, jobs, and courses like, and what effects their job preference. And this study also aims at helping the students with their future plans such as admission to a school of higher grade and choosing their job. For this study, we distributed 340 cpoies to the students in security related majors at 4 four-year colleges and 1 two-year college, and collected 298 copies by means of quota sampling method. For collected questionnaires, we used individual T-test verification and one-way ANOVA analysis to grasp the situation. Significance standard for the test results was set as p<0.05. Following are the test results. First, the analysis on students' satisfaction rate resulted in male students' average of 2.42, compared to female students' average of 2.10, which shows female students have higher satisfaction rate in choosing their majors than male students. Secondly, The results on analysis of satisfaction rate on their curriculums, classes, and majors show that students in security-related majors showed different satisfaction rate and different averages according to their sex and the year of the college. The study indicates that males have higher satisfaction rate on curriculum than females, with male students' average of 2.63 and female students' average 2.88. According to the year of the college, there was a significant difference statistically, Statistics show that students at two-year college have higher satisfaction rate than those at four-year college, with two-year college students' average of 2.48 and four-year college students' of 2.74. students have the average of 3.56. The higher year they were in, the more improvement the curriculum required. When it comes to convenience offer for employment, male students expected more from school than female students, with males' average of 2.74 and females' average of 4.07. Male students marked higher than female students in the extent of job information offer, with males' average of 2.96 and females' average of 2.59. Fourthly, when students in security-related majors were surveyed on their consciousness of their future plans such as getting jibs, two-year college students had more certificates of qualification for employment than four-year college students. What they do preponderantly in preparation for employment was studying foreign languages, which took up 40.4%. And when they were asked on their confidence for employment, positive answers were far more than negative ones with the percentage of 39.6%, while negative took up just 14.0%. Fifthly, when it come to the students in security-related students' job preferences, 49.2% preferred safe job conditions in public security area and 34% preferred private guard or private security organizations. And in the public security area, the highest percentage of 28.6 preferred to work in presidential security service. In the area of private security, 21.2% showed interests in private guard and private security organizations.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.139-155
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• 2009

For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

• Progress in Medical Physics
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• v.17 no.4
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• pp.232-237
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• 2006

The aim of this study was to develop the calculation algorithm of source strength of Ir-192 source In terms of the absorbed dose to water instead of an apparent activity (Ci). For this work the Multi Purpose Brachytherapy Phantom(MPBP) was developed, which was designed to locate the source and the chamber precisely at a specific position Inside the water phantom. The reference point of measurement was set at the 5 cm distance along the transverse axis of the source. For a brachytherapy source calibration, the absorbed dose to water calibration factor ($N_{D.W.Q}$) of an lonization chamber were determined and then apply standard protocols of absorbed dose to water. The calibration factor ($N_{D.W.Q}$) of the ion chamber (TM30013, PTW, Germany) was determined using the EGSnrcCPP Monte Carlo Code. The calculated calibration factor ($N_{D.W.Q}$) was 5.28 cGy/nC. The calculated factor was then used to determine the absorbed dose to water from which the air kerma strength for an Ir-192 source can be easily derived at the reference point (5 cm). The calculated air kerma strength showed discrepancies of -0.6% to +1.8% relative to the air kerma strength provided by the vendor, In this work we demonstrated that the air kerma strength ($S_k$) could be determined from the absorbed dose to water calibration factor for Ir-192 source. In audition, this source calibration method could be applied directly to the dose Calculation formalism of AAPM report TG-43.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.31
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• pp.27-56
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• 2006

Today's financial institutions usually take environmental issues seriously into consideration as they could not evade lender liability in an increasing number of cases. On the international scene, a brand-new concept of the "Equator Principles" in the New Millenium has driven more and more international banks to adopt these Principles in project financing. Sustainable development has been a key word in understanding new trends of the governments, financial institutions, corporations and civic groups in the 21st century. The Equator Principles are a set of voluntary environmental and social guidelines for sustainable finance. These Principles commit bank officers to avoid financial support to projects that fail to meet these guidelines. The Principles were conceived in 2002 on an initiative of the International Finance Corporation(IFC), and launched in June 2003. Since then, dozens of major banks, accounting for up to 80 percent of project loan market, have adopted the Principles. Accordingly, the Principles have become the de facto standard for all banks and investors on how to deal with potential social and environmental issues of projects to be financed. Compliance with the Equator Principles facilitates for endorsing banks to participate in the syndicated loan and help them to manage the risks associated with large-scale projects. The Equator Principles call for financial institutions to provide loans to projects under the following circumstances: - The risk of the project is categorized in accordance with internal guidelines based upon the environmental and social screening criteria of the IFC. - For Category A and B projects, borrowers or sponsors are required to conduct a Social and Environmental Assessment, the preparation of which must meet certain requirements and satisfactorily address key social and environmental issues. - The Social and Environmental Assessment report should address baseline social and environmental conditions, requirements under host country laws and regulations, sustainable development, and, as appropriate, IFC's Environmental, Health and Safety Guidelines, etc. - Based on the Social and Environmental Assessment, Equator banks then make agreements with borrowers on how they mitigate, monitor and manage the risks through a Social and Environmental Management System. Compliance with the plan is included in the covenant clause of loan agreements. If the borrower doesn't comply with the agreed terms, the bank will take corrective actions. The Equator Principles are not a mere declaration of cautious banks but a full commitment of lenders. A violation of the Principles in the process of project financing, which led to an unexpected damage to the affected community, would not give rise to any specific legal remedies other than ordinary lawsuits. So it is more effective for banks to ensure consistent implementation of the Principles and to have them take responsible measures to solve social and environmental issues. Public interests have recently mounted up with respect to environmental issues on the occasion of the Supreme Court's decision (2006Du330) on the fiercely debated reclamation project at Saemangeum. The majority Justices said that the expected environmental damages like probable pollution of water and soil were not believed so serious and that the Administration should continue to implement the project seeking ways to make it more environment friendly. In this case, though the Category A Saemangeum Project was carried out by a government agency, the Supreme Court behaved itself as a signal giver to approve or stop the environment-related project like an Equator bank in project financing. At present, there is no Equator bank in Korea in contrast to three big banks in Japan. Also Korean contractors, which are aggressively bidding for Category A-type projects in South East Asia and Mideast, might find themselves in a disadvantageous position because they are generally ignorant of the environmental assessment associated with project financing. In this regard, Korean banks and overseas project contractors should care for the revised Equator Principles and the latest developments in project financing more seriously. It's because its scope has expanded to the capital cost of US$10 million or more across all industry sectors regardless of developing countries or not. It should be noted that, for a Korean bank, being an Equator bank is more or less burdensome in a short-term period, but it must be conducive to minimizing risks and building up good reputation in the long run.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.77-84
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• 2019

Objectives : The Illness Intrusiveness Rating Scale (IIRS) is a well-validated self-report instrument for assessing negative impact of chronic illness and/or adverse effects of its treatment on everyday life domains. Although extensive literature probed its psychometric properties in medical illness, little attention was paid for its validity for psychiatric population. This study aimed to test factorial structure of the Korean Version of the IIRS (IIRS-K) in a consecutive sample of psychiatric outpatients. Methods : Data set of 307 first-visit patients of psychiatric clinic at Guri Hanyang univ. Hospital were used. Exploratory and confirmatory factor analysis, internal consistency were tested in IIRS-K. We also checked Spearman's correlation analysis between IIRS-K, Zung's self-report anxiety scale and Zung's self-report depression scale. Results : 76.9% of the patients were with anxiety disorder and depressive disorder. The principal component factor analysis of the IIRS-K extracted three-factor structure accounted for 63.2% of total variance that was contextually similar to the original English version. This three-factor solution showed the best fit when tested confirmatory factor analysis compared to the original IIRS, two-factor model of IIRS-K suggested from medical outpatients, and one-factor solution. The IIRS-K also showed good internal consistency (Cronbach's α=0.90) and good convergent validity with anxiety and depression scales. Conclusions : The IIRS-K showed the three-factor structure that was similar but not identical to original version. Overall, this study proved factorial validity of the IIRS-K and it can be used for Korean clinical population.