• Korean Journal of Materials Research
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• v.10 no.7
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• pp.505-514
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• 2000

The carburizing behavior and fatigue properties of the plasma carburized low carbon Cr-Mo steel(0.176C-1.014Cr-0.387Mo) have been investigated. The effective case depth in plasma carburized steel increased up to 50% in comparison with that of gas carburizing, and this case depth increased with the increasing surface carbon content. With increasing time in plasma carburizing, the surface carbon content increased but its increasing rate decreased. Fatigue properties were studied in terms of microstructure, case depth, retained austenite and residual stress near the surface. The fatigue limit of the plasma carburized steel was higher than that of gas carburized one. The initiation of microcracks and initial crack propagation were retarded due to a relatively little surface and internal oxidation layer in plasma carburized steel. Fractography showed the crack initiated at the surface, and transgranular fracture at surface layer was more predominant in plasma carburized steel compared to that of gas carburized steel.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.1
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• pp.23-33
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• 2023

Purpose: The incidence and prevalence of inflammatory bowel disease (IBD) are increasing along with an increasing number of patients with comorbid conditions like psychiatric and behavioral disorders, which are independent predictors of quality of life. Methods: Non-overlapping years (2003-2016) of National Inpatient Sample and Kids Inpatient Database were analyzed to include all IBD-related hospitalizations of patients less than 21 years of age. Patients were analyzed for a concomitant diagnosis of psychiatric/ behavioral disorders and were compared with IBD patients without psychiatric/behavioral disorder diagnoses for outcome variables: IBD severity, length of stay and inflation-adjusted hospitalization charges. Results: Total of 161,294 IBD-related hospitalizations were analyzed and the overall prevalence rate of any psychiatric and behavioral disorders was 15.7%. Prevalence rate increased from 11.3% (2003) to 20.6% (2016), p<0.001. Depression, substance use, and anxiety were the predominant psychiatric disorders. Regression analysis showed patients with severe IBD (odds ratio [OR], 1.57; confidence interval [CI], 1.47-1.67; p<0.001) and intermediate IBD (OR, 1.14; CI, 1.10-1.28, p<0.001) had increased risk of associated psychiatric and behavioral disorders than patients with a low severity IBD. Multivariate analysis showed that psychiatric and behavioral disorders had 1.17 (CI, 1.07-1.28; p<0.001) mean additional days of hospitalization and incurred additional $8473 (CI, 7,520-9,425; p<0.001) of mean hospitalization charges, independent of IBD severity. Conclusion: Prevalence of psychiatric and behavioral disorders in hospitalized pediatric IBD patients has been significantly increasing over the last two decades, and these disorders were independently associated with prolonged hospital stay, and higher total hospitalization charges.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.267-275
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• 2023

The cement industry has been contributing to solve the wastes problem by using various combustible wastes as alternative fuel to replace natural coal. To use more alternative fuels such as waste plastics, in the cement manufacturing process, it is necessary to stably burn alternative fuels and reduce air emissions such as NOx. This study is a case study on the multi-stage combustion calciner process, which is a technology that decreases the amount of NOx while increasing the use of alternative fuels. This study is a case study on the multi-stage combustion process, a technology that reduces the amount of harmful air emissions such as NOx while increasing the use of alternative fuels. Along results of comparing before and after applying the technology to actual cement manufacturing facilities, the amount of coal consumption decreased by 38 %, waste plastics consumption increased by 122 %, and NOx emissions decreased by 17 %. Results show that increasing the use of alternative fuels and reducing NOx emissions by multi-stage combustion is effective.

• Journal of the Korean Society for Nondestructive Testing
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• v.11 no.1
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• pp.38-43
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• 1991

The relationship between eddy current response and case hardening depth has been studied on SM40C(KS D-3752) and SCM440(KS D-3711) steels which were surface hardened by high frequency induction hardening. The results obtained in this study were as follows ; 1) Case hardening depth was successfully measured by observing the eddy current impedance changes of each steel. The impedance decreased linearly with increasing case hardening depth. 2) For large impedance gradient between the hardened surface and core metal, the eddy current response was more sensitive to case hardening depth than for low impedance gradient.

• Journal of Chest Surgery
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• v.15 no.1
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• pp.112-117
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• 1982

Communications of coronary arteries with the cardiac cavities have first time been described by Krause in 1865 in a case of an accessory artery draining into the pulmonary artery and later Cayla in a case of a right coronary artery entering the right ventricle. The initial cases have been found accidentally at autopsies, however In recent years after the Introduction of angiography and coronary arteriography, the malformation Is diagnosed during life and is corrected surgically. These conditions are unusual entitles since the advent of angiography they are being diagnosed with increasing frequency. Three patients who had surgical correction of coronary-cardiac chamber fistula at our hospital are presented. In the first case and second case, coronary arteriovenous fistula was corrected horizontal mattress suture ligation with pladget under the cardiopulmonary bypass and third case was corrected double ligation with cardiopulmonary bypass standby. The postoperative courses were uneventful. They discharged without any fistula related complica-tions.

• Electronics and Telecommunications Trends
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• v.33 no.2
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• pp.64-76
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• 2018

This paper addresses the antitrust case of Google's general search service to find evidence and logic used for defining markets, and the proof of dominant power and its abuse in detail. This antitrust case has certain meaning because it is not easy to apply traditional approaches to a general search service, which has two-sided market characteristics. This paper finds some implications through an analysis of the antitrust case shown below. First, for market definition, the overall qualitative analysis can be used to draw conclusions without a quantitative analysis, such as a Small but Significant and Non-transitory Increasing in Price (SSNIP) analysis. Second, the multi-homing behavior seems to be one of the key factors in judging the dominant power in Internet-based services. Lastly, the fact that the value of traffic can differ based on the traffic source needs to be considered to address the competition issue of Internet-based services.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.1
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• pp.215-228
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• 1998

The purpose of this study is analysis of 52 dissertations on assertiveness training which presented from 1982 to 1997 in Korea. It was diversified the research purpose to by 1) time of publication or presentation 2) research design, characteristics of subjects used in each study 3) related concepts, the effects of nursing interventions according to related concepts 4) the effects of nursing interventions according to the subjects 5) the effects of nursing interventions according to the frequency and the period of assertiveness training 6) the effects of nursing interventions according to the group size. 7) the effects of nursing interventions according to the necessary time per round. Findings obtained in the study were as follows : 1. At the point of the numbers of studies presented by year, the number of the studies tend to increase, especially the most plentiful papers were presented during five years from 1991 to 1995. 2. Research design of the studies belong to experimental research. The subjects of research consists of 5 Nursing related subjects and 47 Non-nursing related subjects so that Non-nursing related subjects contain much large proportion. 3. When studies were classified by the related concepts, they were classified that 17 studies were by assertiveness & assertive behaviour, 15 ones anxiety, 9 ones self & ego, 7 ones depression. It can be inferred that studies related to assertive behaviour, self & ego, sociality and power of learning were increasing. Otherwise, studies related to anxiety, depression, aggression, shyness and anguish were decreasing. 4. At the point of the nursing intervention effect by the subjects, the concepts of assertive behavior, feeling of self-respect and sociality were increasing, but the concepts of conflict and interpersonal stress were decreasing and the concepts of anxiety and sociality were ineffective in the subjects related Nursing. On the contrary, the concepts of assertive behavior, sociality and personalty were increasing, but the concepts of anxiety, depression, aggression, shyness, self-estranged feeling were decreasing and the concepts of assertive behavior, aggression, personalty, power of learning, anxiety, self-concepts and self-expression were ineffective in the subjects related Non-Nursing. 5. 18 studies can be found, which investigated 10 times for 5 weeks from the point of the nursing intervention effect by the times and the period of assertiveness training. In case of over 5 times of assertiveness training, assertiveness, assertive behavior and personality(tranquility, depression) increased. In 6 times, feeling of self-respect & egorespect increased but depression, interpersonal stress and anxiety decreased. In over 10 times, shyness, shame and feeling of self-estrangement decreased. In over 12 times, interpersonal anxiety decreased. 6. In the event of nursing intervention effect by the size of the group, it was greatest within 10 persons in 21 studies. In case of within 10 to 20, only feeling of self-expression were ineffective. Particularly, in case of over 31 persons, there were no ineffective concepts. 7. At the viewpoint of nursing intervention effect by the necessary time of one time, it was greatest within 1 to 2 hours in 32 studies. In case of within 1hour, aggression, power of learning and assertiveness were ineffective. In case of within 1 to 2 hours, assertive behavior, self-expression, personality and anxiety were ineffective. Particularly, in case of within 2 to 3 hours, there were no ineffective concepts.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.6
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• pp.527-535
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• 2019

Purpose: There is increasing prevalence of psychiatric disorders among inflammatory bowel Disease (IBD) population. Further, presence of psychiatric disorders has been shown as an independent predictor of quality of life among patients with IBD. We intended to explore the prevalence of various psychiatric disorders among pediatric and young adult population with IBD as a population-based analysis. Methods: We did a retrospective case control analysis using a deidentified cloud-based database including health care data across 26 health care networks comprising of more than 360 hospitals across USA. Data collected across different hospitals were classified and stored according to Systematized Nomenclature of Medicine-Clinical Terms. We preidentified 10 psychiatric disorders and the queried the database for the presence of at least one of the ten psychiatric disorders among IBD patients between 5 and 24 years of age and compared with controls. Results: Total of 11,316,450 patients in the age group between 5 and 24 years and the number of patients with a diagnosis of IBD, Crohn's disease or ulcerative colitis were 58,020. The prevalence of psychiatric disorders was 21.6% among IBD mainly comprising of depression and anxiety disorder. Multiple logistic regression analysis showed, IBD is 5 times more likely associated with psychiatric disorders than controls, p<0.001). We showed a steady increasing trend in the incidence of psychiatric disorders among IBD patients (2% in 2006 to 15% in 2017). Conclusion: Largest population-based analysis demonstrated an increased prevalence of psychiatric disorders among IBD patients. Our study emphasizes the need for psychological and mental health services to be incorporated as a part of the routine IBD clinic.

• Journal of Korean Association for Spatial Structures
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• v.2 no.1 s.3
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• pp.85-92
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• 2002

Two way grid single-layer domes are of great advantage in fabrication and construction because of the simple fact that they have only four members at each junction. But, from a point of view of mechanics, the rectangular latticed pattern gives rise to a nonuniform rigidity-distribution in the circumferential direction. If the equivalent rigidity is considered in the axial direction of members, the in-plane equivalent shearing rigidity depends only on the in-plane bending rigidity of members and its value is very small in comparison to that of the in-plane equivalent stretching rigidity. It has a tendency to decrease buckling -strength of dome considerably by external force. But it is possible to increase buckling strength by the use of roofing covering materials connected to framework. In a case like this, shearing rigidity of roofing material increases buckling strength of the overall structure and can be designed economically from the viewpoint of practice. Therefore, the purpose of this paper, in Lamella dome and rectangular latticed dome that are a set of 2-way grid dome, is to clarify the effects of roofing covering materials for increasing of buckling strength of overall dome. Analysis method is based on FEM dealing with the geometrically nonlinear deflection problems. The conclusion were given as follows: 1. In case of Lamella domes which have nearly equal rigidity in the direction of circumference, the rigidity of roofing covering materials does not have a great influence on buckling-strength, but in rectangular latticed domes that has a clear periodicity of rigidity, the value of its buckling strength has a tendency to increase considerably with increasing rigidity of roofing covering materials 2. In case of rectangular latticed domes, as rise-span-ratio increases, models which is subjected to pressure -type-uniform loading than vertical-type-uniform loading are higher in the aspects of the increasing rate of buckling- strength according to the rate of shear reinforcement rigidity, but in case of Lamella dome, the condition of loading and rise-span-ratio do not have a great influence on the increasing rate of buckling strength according to the rate of shear reinforcement rigidity.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.883-889
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• 2009

The importance of cost estimate in early stage such has been increasing due to market change and severe competition in construction industry. Because the adjustable budget is only 20% after design stage, most of the crucial decisions to influence cost is made in the early stage. However, in the early stage, the project scope is not defined completely so that estimator has inaccurate information to make critical decision. Therefore, this research suggests the cost estimate method using case-based reasoning. Case-based reasoning is appropriate for the early cost estimating, as it has the strength of rapidity and convenience in cost estimation. This research analyzes 84 actual data of public apartment on the scale of 11~15 stories. In order to extract the most similar case, at the first step this research identifies influence factors and calculates attribute similarity. In case-based reasoning, the most challenging task is determining attribute weight. At the third step, this research calculates case similarity which is aggregated attribute similarity multipled by attribute weight. Finally, extracts the most similar case which has the highest score of case similarity.