• 한국초전도ㆍ저온공학회논문지
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• 제7권2호
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• pp.11-15
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• 2005

The I$_{c}$ degradation behavior of Bi-2223 tapes bent at RT and 77K were investigated using the bending device invented by Goldacker. Test results on fixing the tape at RT and 17K showed no difference. At 17K and RT bending, the critical strain was 0.67 and 0.50$\%$, respectively, for the VAM-l tape. For the AMSC tape, it was 0.94 and 0.88$\%$, respectively. These results show that there is additional residual stress in the superconducting filaments to be bent at 17K which shifts the formation of cracks into smaller bending radii. This was proved by computational analysis based on the mixture rule of composites. For the VAM-l tape, the Ie degradation behavior using the Goldacker type device shifted to higher strain levels at about 0.5$\%$, as compared with the FRP sample holders which have a critical bending strain of about 0.24$\%$. Also, for the externally reinforced AMSC tape, Ie degradation using the Goldacker type device begins at a higher strain level, at 0.88$\%$ as compared with using FRP sample holders, at 0.74$\%$. The difference between both cases can be explained by the tensile' and thermal stresses that the tapes were subjected to during fixing (soldering) when the FRP sample holders were used.

• 한국응급구조학회지
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• 제10권3호
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• pp.5-20
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• 2006

Purpose: This study examines the degree of empowerment recognized by the 1st paramedics and the trend of their critical thinking, analyzes correlations between empowerment and critical thinking to reveal whether there is statistically significant difference between them and then is to provide basic materials necessary for research on empowerment and critical thinking. Method: This study distributes 105 structured self-report questionnaires to the 1st emergency medical technicians working at fire fighting police boxes, general hospitals, clinics and emergency medical information centers in G Metropolitan City and J province from April 29 to May 28, 2006, collects their responses directly and analyzes results with t-test, F-test(ANOVA) and Pearson's Correlation Coefficient. Result: 1. First, average score of empowerment of subjects was 4.68 out of 6 and according to scores by area, capacity 5.98 was highest, followed by significance 5.41, self- determination 4.44 and effectiveness 3.79. 2. degree of empowerment according to general characteristics of subjects showed statistically significant differences in final education(F=2.714, p= .049), level of salary (F=3.298, p= .014) and satisfaction of current job (F=5.399, p= .001). 3. average score of critical thinking of subjects was 3.28 out of 7 and according to areas, no bias 3.95 was highest, followed by maturity 3.68, structure 3.35, inquisitiveness 3.11, pursuit of truth 3.07, critical thinking and self-confidence 3.00, analyticity 2.98. 4. degree of critical thinking by general characteristics of subjects showed statistically significant differences in age(F=2.577, p= .041), final education (F=7.877, p= .000), current workplace (F=3.513, p= .018), level of salary(F=4.628, p= .002), satisfaction with current job(F=6.879, p= .000) and intention to transfer current job(t=15.21, p=.000). 5. as a result of correlations between empowerment and critical thinking of subjects, Pearson correlation coefficients between whole empowerment and critical thinking were r= .21, p=.013. Conclusion: It is considered that the 1st paramedic managers must seek how to keep and manage empowerment and development of education and training program which can enhance critical thinking is needed. Further, emergency educators must develop educational program based on the concept of empowerment to establish early awareness of a desirable organization culture and increase understanding of empowerment in the process of education.

• 대한교통학회지
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• 제19권6호
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• pp.195-205
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• 2001

본 연구는 고속도로 합류부의 교통 특성 분석을 목적으로 한다. 합류부가 기본구간과 구별되는 가장 큰 특징은 연결로 차량의 본선합류이며, 이로 인해 합류부의 교통 특성은 기본구간과 크게 대별된다. 이러한 합류부의 교통 특성을 파악하기 위하여 본 연구에서는 합류 시 요구되는 임계차두간격과 이로 인해 결정되는 최대 진입가능 교통량이라는 두 요소에 초점을 맞추었다. 본 연구에서는 확률 모형을 통해 합류 용량 산정 시 임계차간간격(Critical time gap)대신 임계차두간격(Critical time headway)이 적용될 수 있도록 모형을 구축하였다. 기존 연구에서는 합류 용량 산정시 합류하고자 하는 진입 차량은 본선을 주행하는 차량들 사이의 차간간격이 임계차간간격 이상이면 모두 진입하는 것으로 간주되어왔다. 또한 임계차간간격은 교통류 상태와는 관계없이 항상 동일한 값으로 적용되었다. 그러나, 합류 과정에서 필요한 차간간격은 동일한 운전자에 대해서도 다른 교통류 상태 예를 들어, 교통류의 상대속도 차이 등에 따라 다르게 나타날 수 있으므로 정해진 임계차간간격이 합류 과정 시불충분한 값으로 인식될 수도 있게 된다. 따라서, 본 연구에서는, 먼저 모든 교통류 상태에 대한 임계차두간격 산출 원리를 제시하였다. 또한 도출된 임계차두간격을 통해 최대 진입가능 교통량 및 합류부의 최대 통과 교통량을 산출하였다.

• 대한간호학회지
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• 제5권2호
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• pp.29-37
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• 1975

The purpose of this study was to measure the extent of stress existing in hospitalized patients which might play an important part in delaying recovery of patients. The study was conducted July l0th through 16th, 1975; a total of 146 patients from 2 general hospitals in Seoul were sampled. Questionnaire, formulated by the researcher, were used to gather necessary information concerning stress in accordance with the physical, psychological, economical and social variables. Data were analysed by mean stress score, and the significances were tested by Critical Ratio. The results were as follows ; 1. No significant difference was revealed in accordance with sex, however, male patients showed higher stress scores on the economic variables. 2. No. significant difference was apparent in accordance with marital status, however, the unmarried showed a tendency of higher stress scores at all variables. 3. Significant difference was revealed between the age group of 35-49 years and that of over 50 years; the age group of 18-34, and 35-49 years showed higher stress scores. 4. No. significant difference was revealed in accordance with previous experience of hospitalization, however, the group with previous experience tends to show higher stress scores in all variables. 5. No significant difference was revealed in accordance with the types of admission, however, group admitted on emergency showed higher stress scores compared to the group admitted plained in advance at social and economic variables. 6. No significant difference was revealed in accordance with the length of hospitalization, however, tendencies were apparent that the longer the length of hospitalization, the lower the mean stress scores.

• 한국과학교육학회지
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• 제12권3호
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• pp.49-59
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• 1992

New-Piagetian theory has proposed that mental capacity and mental demand do a critical role in human cognitive processes. In this study, the students' mental capacity and the mental demand of the given problems were examined. The principal findings of the study are as follows; (1) There was no significant difference among achievement scores of subjects (3rd grade students of middle school, 2nd grade students of high school, 3rd grade students of high school) in the items of balance that needed specific content knowledge. But, in the Newton's 2nd law items that needed specific content knowledge, there was significant difference be ween3rd grade students of middle school and high school students(2nd, 3rd). According to increase of mental demand, middle school students' achievement score appeared to decrease linearly. However high school students' achievement score didn't change untill they faced the items of critical mental demand. When mental demand was beyond critical mental demand,their score was decreased rapidly. (2) According to hierchical analysis of items, the more mental demand an item needed, the higher or at least the same hierachical item was. These results showed that mental demand was the main factor which decided diffculties of problem solving (3) It was possible for students to solve the newton's 2nd law item that had one or two more mental demand relative to balance beam item. Although the item needed the same mental demand.students recognized that the Newton's 2nd law items were easier than the balance beam items.

• 한국초전도ㆍ저온공학회논문지
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• 제22권2호
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• pp.38-43
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• 2020

This paper presents comparative research on characteristics of air-cored and iron-cored high-temperature superconductor (HTS) field winding synchronous motors. The 100 kW air-cored model is designed analytically by Spatial Harmonic Method, and based on this model, the iron-cored model having the same output power is designed for comparison. Due to the substantial difference of permeability property between air and iron-core, there is a difference of magnetic field magnitude and angle with respect to the HTS tape c-axis, resulting in a different critical current of the field winding considering the anisotropic property of HTS tape. For a detailed comparison between two models, the following key motor characteristics are calculated through the Finite Element Method (FEM) simulation: 1) critical current; 2) HTS wire length; and 3) torque characteristics. From the simulation results, it can be confirmed that the critical current value of the iron-cored model increases by 33 %. Also, in the case of the superconducting wire consumption, those of the iron-cored and air-cored models are 95.3 m and 815.6 m, respectively. So the wire usage can be reduced to about 88 % by using iron core. However, in terms of torque characteristics, the torque ripple of the iron-cored model is about twice as large as that of the air-cored model, which may be a disadvantage on vibration and acoustic noise.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권4호
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• pp.456-459
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• 2008

Post-operative recurrence of cystic lesion is a great concern for clinician, patients, and their family, especially in case of odontogenic keratocyst, which has aggressive behavior and high recurrence rate. The purpose of this study was to evaluation clinical characters of OKC, focusing of the recurrence rate and proposed critical follow-up period. 58 cases (aged 9 to 66, 33 males and 25 females) of OKC were reviewed for sex of patients, location, size, operative procedure type, radiographic findings, histopathologic findings, post-operative recurrence time, from 2000 to 2005 at Yonsei Medical Center, were selected. The computerized statistical analysis was carried out with SAS system. 18 of 58 cases (31.03%) were recurred and this study revealed no statistically significant difference in recurrence rate for sex, location, size, radiographic findings, histopatologic findings, operative procedure type, recurrence timing. 3 out of 18 cases (16.7%) showed one or more recurrence. This was statistically significant difference (P=.0264). In this study, 15 of 18 cases (83.3%) were observed recurrence during 4 years after removal of the OKCs, we suggest critical follow-up period during 4 years after operation.

• 한국항해항만학회지
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• 제44권1호
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• pp.10-19
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• 2020

경인항은 컨테이너 및 일반부두 시설을 갖추고 배후 관광자원 연계가 가능한 다기능 항만으로 개발되었으나, 소형항만이라는 한계와 주변 항만과 중복, 연계성 부족으로 인하여 어려움을 겪고 있다. 하지만 경인항 또는 인근에 물류거점이 필요한 입주기업은 특성상 목재류, 철재류, 공산품 등 특정 수출입 품목을 경인항을 통하여 처리하고 있다. 이러한 측면에서 볼 때 경인항 이해관계자의 효용분석을 통한 경인항 활성화 방안을 수립하는 것은 중요하다. 본 연구에서는 컨조인트 분석을 활용하여 경인항 이해관계자의 선호도를 분석하고, 각 이해관계자의 선호도 차이를 제시하는 것을 연구의 목적으로 하였다. 연구결과, 터미널 집단은 선석 접안능력을 가장 중요하게 고려하고 있으며, 선사는 인센티브 규모를, 입주기업은 항만물류비를 가장 중요한 것으로 인식했다. 경인항 관련 당사자들은 인식의 차이를 인지하고, 경인항 활성화를 위해 관계기관의 협조 및 운영사간의 상호협력 등 경인항 특성에 맞는 화주 발굴 및 제도적 정비를 갖출 필요가 있다.

• Tuberculosis and Respiratory Diseases
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• 제81권4호
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• pp.289-298
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• 2018

Background: Obstructive airway disease patients with increased variability of airflow and incompletely reversible airflow obstruction are often categorized as having asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS). ACOS is heterogeneous with two sub-phenotypes: asthma-ACOS and COPD-ACOS. The objective of this study was to determine the difference in risk of exacerbation between the two sub-phenotypes of ACOS. Methods: A total of 223 patients exhibiting incompletely reversible airflow obstruction with increased variability (spirometrically defined ACOS) were enrolled. These patients were divided into asthma-ACOS and COPD-ACOS according to their physician's diagnosis and smoking history of 10 pack-years. Within-group comparisons were made for asthma-ACOS versus COPD-ACOS and light smokers versus heavy smokers. Results: Compared to patients with COPD-ACOS, patients with asthma-ACOS experienced exacerbation more often despite their younger age, history of light smoking, and better lung function. While the light-smoking group showed better lung function, they made unscheduled outpatient clinic visits more frequently. On multivariate analysis, asthma-ACOS and poor inhaler compliance were significantly associated with more than two unscheduled clinic visits during the previous year. Conclusion: Spirometrically defined ACOS includes heterogeneous subgroups with different clinical features. Phenotyping of ACOS by physician's diagnosis could be significant in predicting future risk of exacerbation.

• 패션비즈니스
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• 제16권4호
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• pp.64-74
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• 2012

The purpose of this study would be to find out the relationship of social as a sign of fashion image and the followership. This study is classified into theoretical and experimental research. Following are the summary of the results revealed through the experimental study. First, The relationship of oneself pursuit of fashion image types and leader's favourite fashion image types for regression analysis result indicated significant difference. Second, The factor analysis of followership are used, developed by Colangeol is asking. The results of factor analysis are four types classification as to Active Participation, Convergence objective, Team Spirit, Critical Thinking. Third, The relationship of types of fashion images and factor variance of followership indicated a difference in Active Participation factors. But The relationship of types of leader's fashion images and factor variance of followership indicated a difference in Convergence objective factors. Analysis of the fashion image based on the conceptual properties of followership is to understand the characteristics of followers, and the leader's image based on research for building materials will be provided.