• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.2
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• pp.217-225
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• 2010

Most of the steel bridges in Korea are being currently designed by the allowable stress design method that uses the conventional deterministic factors of safety. However the limit state design based on the concept of probability, statistics and reliability engineering is becoming very popular as a global standard deign method, leading the rational and economic bridge design. As part of the fundamental research to establish the load and resistance factor design(LRFD) of steel bridges considering domestic environmental conditions and regional characteristics, an experimental design is conducted by applying AASHTO-LRFD specification especially to a steel closed-box girder, which occupies relatively a large portion of steel bridges in Korea. Throughout the experimental design according to various sectional changes, some of the issues to be considered in the LRFD design of a composite steel closed-box girder bridge are examined. In this process, an Excel-based design verification program is developed for easy computation and prevention of errors. Quantitative reliability levels of the bridge sections designed by LRFD are also estimated using a reliability analysis method, and compared with the target reliability indexes applied in the LRFD design to verify the validity of the procedure and methodology used in this study.

• Sleep Medicine and Psychophysiology
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• v.22 no.1
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• pp.20-24
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• 2015

Objectives: Restless legs syndrome (RLS) is a common sleep disorder in adults with diabetes. This study investigated the frequency of RLS and clinical correlations in children and adolescents with type 1 diabetes. Methods: This study included 55 consecutive patients (21 males, age $12.6{\pm}3.4years$) with type I diabetes that were regularly treated at the Department of Pediatric Endocrinology. RLS was diagnosed by intensive interviews which also included the Epworth Sleepiness Scale (ESS) and International RLS Rating Scale (IRLSRS). Patients also received neurological examinations and laboratory tests for diabetes, iron metabolism and renal function. Results: Thirteen patients (23.6%, 6 males) were compatible for the diagnostic criteria of RLS. None of the RLS patients showed abnormal findings in neurological evaluations and 7 patients had familial history of RLS. Demographic and laboratory findings were not different between the patients with or without RLS. The RLS group showed significantly increased ESS and IRLSRS scores. Conclusion: RLS was prevalent in children and adolescents with type 1 diabetes. The association between RLS and diabetes-related laboratory findings requires further investigation.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.15 no.1
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• pp.75-81
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• 2004

Objectives：This study was designed to compare the emotional/behavioral characteristics between the siblings of children with autism and normally developing children. Methods：The subjects were 34 children between 10 and 16 years of age, 17 siblings of children with autism, 17 siblings of nonhandicapped children. Both groups performed CDI(Kovacs' Children Depression Inventory), RCMAS(Revised Chidren's Manifest Anxiety Scale), SPPC(Self-Perception Profile for Children), Self-esteem scale. Their mothers performed K-CBCL(Korean -Child Behavior Checklist). The results of those test were analysed by Student's-test. Results：Both social competence and total social competence subsclae scores were significantly lower in sibling group of children with autism than in control group. However, each group was not significantly different on the scores of internalizing symptom, externalizing symptom subscale of CBCL, CDI, RCMAS, Self-Perception Profile and Self-esteem scale. Conclusion : Siblings of children with autism had a lower social competence than normal control group. Group comparisons indicated that siblings of children with autism and normal children did not differ on any self-report measures such as anxiety, depression, self-concept and self-esteem. Further research using more subjects will be needed.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.87-93
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• 2010

Purpose: The purpose of this study was to compare the retention of the two denture adhesives with a silicone edentulous model and a resin denture base in vitro study. Material and methods: The experimental groups were used two denture adhesives and classified into 5 subgroups each. Subgroups were divided by the number of times the saliva sprayed. The control group was used synthetic saliva only. Dislodging tensile strengths were applied to the resin denture base using Instron in 3 directions ; vertical, lateral, and anterior-posterior. Results: The retention of two denture adhesives was increased significantly than saliva alone (P <.05). In each denture adhesives, the retention of saliva sprayed first was decreased than denture adhesive alone, but it didn't have significant differences. Whenever saliva sprayed repeated, the retention was decreased significantly than saliva sprayed first (P <.05). In each denture adhesives, vertical retentive force was highest than lateral and anterior-posterior retentive forces, and anterior-posterior retentive force was higher than lateral retentive force. This results were significantly different (P < .05). Significant differences of the retentive ability among two denture adhesives were not observed. Conclusion: From the results, use of the denture adhesives resulted in improved retentive ability of denture. Especially retentive force was highest in vertical direction.

• Sleep Medicine and Psychophysiology
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• v.18 no.1
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• pp.29-34
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• 2011

Objectives: The purposes of this study were to estimate the effect of mandibular advancement device (MAD) and to evaluate the influence of the advancement amount of mandible in the application of MAD for obstructive sleep apnea (OSA) patients. Methods: From the patients who were diagnosed as OSA by polysomnographic study at Seoul National University Bundang Hospital from January 2007 to February 2009, the patients who chose MAD as treatment option were included in this study. All the patients’ data including clinical records and polysomnographic studies (both pre- and post-treatment) were reviewed and analyzed. Results: Successful results were obtained in 65 patients of 86 patients (75.6%). In the follow-up period, mild discomfort of anterior teeth or temporomandibular joint (TMJ) were described in 28 patients, especially in the cases the amount of mandibular advancement were more than 7.0 mm. There was no direct relationship between the amount of mandibular advancement and clinical outcome. Conclusion: MAD was effective treatment option for the OSA patients regardless of severity. For the prevention of potential dental complications, the amount of mandibular advancement should be considered at the time of MAD treatment.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1571-1576
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• 2002

Purpose : Recently, clinical trials of steroid add-on therapy were reported with variable results in Kawasaki disease. We analyzed the clinical outcomes of patients at high risk of with Kawasaki disease(${\geq}4$ points of Harada score) treated by three commonly used different treatment regimens, with or without corticosteroids. Methods : Medical records of 96 children with Kawasaki disease treated with one of the threee regimens were reviewed retrospectively. Regimen 1 was aspirin(100 mg/kg/day) plus intravenous gamma globulin 2 g/kg single dose; regimen 2, aspirin(100 mg/kg/day) plus intravenous gamma globulin 1 g/kg single dose; regimen 3, regimen 2 plus prednisolone(2 mg/kg/day), followed by tapering two weeks and pulse therapy of methyl prednisolone performed in cases of retreatment. Also low dose aspirin was given in all three regimens for eight weeks after the acute phase. The cardiovascular and laboratory evaluations were performed on acute phase, immediate after acute phase, and subacute phase, eight weeks after treatment. Results : The frequency of coronary artery lesions and laboratory findings in the three different regimens were similar. The more rapid control of fever after treatment was noted in regimen 3. Furthermore the frequency of retreatment was decreased in regimen 3 compared to the other two regimens. Conclusion : Steroid add-on therapy showed some beneficial outcome compared to conventional treatment regimens. The role of steroid in the treatment of Kawasaki disease should be reassessed in systemic manner.

• Journal of the Korea Society of Computer and Information
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• v.5 no.4
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• pp.41-47
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• 2000

In modern dynamic management environment, there is growing recognition that information & knowledge management systems are essential for CEO's efficient/effective decision making. As a key component to cope with this current, we suggest the management performance data-mining system based on IT(Information Technology). This system measures management performance that is considered with both VA(Value-Added), which represents stakeholder's point of view and EVA(Economic Value-Added), which represents shareholder's point of view. The relationship between management performance and 85 financial ratios is analyzed, and then important financial ratios are drawn out. In analyzing the relationship, we applied the explanation-based Gas(Genetic Algorithms) that consider predictability, understanability (lucidity) and reasonability factors simultaneously. To demonstrate the performance of the system, we conducted a case study using financial data over the 16-years from 1981 to 1996 of Korean automobile industry which is taken from database of KISFAS(Korea Investors Services Financial Analysis System).

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.3
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• pp.121-134
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• 2017

With rapid increasing the development and use of IoT Devices, requirements for safe IoT devices and services such as reliability, security are also increasing. In Security engineering, SDLC (Secure Development Life Cycle) is applied to make the trustworthy system. Secure Development Life Cycle has 4 big steps, Security requirements, Design, Implementation and Operation and each step has own goals and activities. Deriving security requirements, the first step of SDLC, must be accurate and objective because it affect the rest of the SDLC. For accurate and objective security requirements, Threat modeling is used. And the results of the threat modeling can satisfy the completeness of scope of analysis and the traceability of threats. In many countries, academic and IT company, a lot of researches about drawing security requirements systematically are being done. But in domestic, awareness and researches about deriving security requirements systematically are lacking. So in this paper, I described about method and process to drawing security requirements systematically by using threat modeling including DFD, STRIDE, Attack Library and Attack Tree. And also security requirements are described via Common Criteria for delivering objective meaning and broad use of them.

• Pediatric Infection and Vaccine
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• v.9 no.1
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• pp.74-78
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• 2002

Purpose : Proper diagnosis of group A streptococcal pharyngitis that may cause chronic diseases in childhood is not easy because its signs and symptoms would be nonspecific. Because results of classical throat culture delays for one to two days, we'd like to determine whether early antibiotics would be introduced with according to the clinical score system. This study was undertaken to evaluate of clinical usefulness of scoring system based on the clinical and laboratory findings. Methods : From Jan. 1998 to Dec. 2000, 10 clinical items based on modified 9 items by Breese in 1977 were checked in patients with pharyngitis who visited on outpatients clinic of pediatrics, Kyunghee University Hospital. We compared the results of throat culture with the points of clinical score system. Results : Out of 45 cases, the positive culture for Group A Streptococcus was 20 and negative culture was 25. When we applied more than 30 points of score, which correspond to 70 percentile of study population, the sensitivity and specificity were 35.0% and 96.0%, respectively. Conclusion : Although sensitivity was relatively low this scoring system, but the high specificity may be useful diagnostic tool in the areas where the rate of isolation of Group A Streptococcus is low.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.1
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• pp.11-20
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• 2008

In probabilistic seismic analysis of nonlinear structural system, dynamic analysis is performed to obtain the distribution of the response estimate using input ground motion time histories which correspond to a given seismic hazard level. This study investigates the differences in the distribution of the responses and the failure probability according to input ground motion models. Two types of input ground motion models are considered: real earthquake records scaled to specified intensity level and artificial input ground motion fitted to design response spectrum. Simulation results fir a nonlinear SDOF system demonstrate that the spectrum matched input ground motion produces larger failure probability than those of scaled input ground motion due to biased responses. Such tendency is more remarkable in the site of soft soil conditions. Analysis results show that such difference of failure probability is due to the conservative estimation of design response spectrum in the range of long period of ground motion.