• 대한전기학회논문지
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• 제38권7호
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• pp.481-491
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• 1989

A compensation strategy for the phase-difference control method, which has been reported as a new driving method of a 2-phase inverter-fed induction motor, is proposed. The phase-difference control method extends the control range of the speed and eliminates the harmonic contents of the output voltage of the 2-phase inverter-fed induction motor. However, the phase-difference angle becomes narrower, motor efficiency deceases more and pulsating torque increases more. As the counterplan for these shortcomings of the phase-difference control method, a hybrid control method which combines the phase-difference control with the voltage control is proposed. The algorithm to realize a hybrid method is presented. As an example, a model composed of 5 regions has been analyzed by computer simulation in terms of motor performance and the results have been compared with experimental results.

• 한국세라믹학회지
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• 제36권8호
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• pp.871-875
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• 1999

Theoretical equation to calculate thermal fatigue life was derived in which slow crack growth theory was adopted. The equation is function of crack growth exponent n. Cyclic thermal fatigue tests were performed at temperature difference of 175, 187 and 200$^{\circ}C$ respectively. At each temperature difference critical thermal fatigue life cycles of the alumina ceramics were 180,37 and 7 cycles. And theoretical thermal fatigue life cycles were calculated as 172, 35 and 7 cycles at the same temperature difference conditions. Therefore thermal fatigue behavior of alumina ceramics can be represented by derived equation. Also theoretical single cycle critical thermal shock temperature difference can be calculated by this equation and the result was consistent with the experimental result well.

• Journal of Applied and Pure Mathematics
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• 제4권1_2호
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• pp.51-61
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• 2022

Let G be a graph. Let f : V (G) → {0, 1, 2, …, k-1} be a map where k ∈ ℕ and k > 1. For each edge uv, assign the label |f(u) - f(v)|. f is called k-total difference cordial labeling of G if |t_df (i) - t_df (j) | ≤ 1, i, j ∈ {0, 1, 2, …, k - 1} where t_df (x) denotes the total number of vertices and the edges labeled with x. A graph with admits a k-total difference cordial labeling is called k-total difference cordial graphs. In this paper we investigate the 4-total difference cordial labeling behaviour of shell butterfly graph, Lilly graph, Shackle graphs etc..

• 대한약침학회지
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• 제2권1호
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• pp.63-71
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• 1999

Counts of RBC and proportion of packed cell volume(PCV) showdc no difference among treatment groups. the values of hemoglobin in rat showed a tendeuy to increase in herbal-acupuncture group, however the values of hemoglobin in guineapig and rabbit showed no significant difference in the treatnent groups. the count of WBC showed high in the chishiI(BL52) herbal-acupuncture group. The proprtion of neutrophils showed no significant difference in rabbit, however the values in guinea-pig and rat showed a tendency to increased in herbal-acupuncture groups. The proportion of lymphocytes in rabbit and guinea-pig showed a tendency to decreast in herbal-acupuncture groups, however the values in rat showed no significant difference. The proportion of Eosinophils and monocytes showed no significant difference in all the treated groups. Results from this study indicated that shinsu(BL23) and chishil(BL52) herbal-acupuncture with palmijihwangtang elivate the biglogical function in Rabbit Guinea-pig and Rat.

• 한국치위생학회지
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• 제7권1호
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• pp.15-30
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• 2007

The main objective of this study is to investigate the improvement of the quality of dental health based on the dental service satisfaction factors of the old dental prosthesis patients of more than 60 years of age who use the dental institutes including dental hospital, clinic, and public health center and to identify the interest in the dental prosthesis as changing paint. Across the country through a questionnaire survey of a question and answer type conducted by the trained dental hygienists or dentist's. Major results of the empirical analysis are as follows. 1. looking at variation of the variables of socio-demographic features of the respondents, the group of female, age distribution of 60-65, average monthly income of 0.5-1 million Won, and schooling background of college showed significant difference. And the prosthesis treatment in terms of the purpose of isiting a dental institute, and the dental clinic in terms of the type of visiting dental institute showed a remarkably significant difference. 2. looking at variation of variables of the general features of the respondents, a prosthesis satisfaction service in terms of age showed significant difference: a prosthesis satisfaction service, dental staffs' service and dental facilities' service in terms of average monthly income showed significant difference: the entire conditions except for the dental facilities' service in terms of schooling and general features showed significant difference: and in terms of the purpose of visiting dental institute, it showed no significant difference. In terms of a visiting dental institute, the prosthesis satisfaction service, dental facilities, overall level of satisfaction, result of treatment, word of mouth and revisit showed significant difference. 3. looking at variation of the variables of post-installation prosthesis satisfaction of the respondents, the prosthesis satisfaction service, dentist's dental service, staffs' service, dental facilities' service and revisit in terms of the prosthesis type: and the prosthesis satisfaction service, word of mouth, revisit and overall level of satisfaction from the perspective of serious concern showed significant difference. The prosthesis satisfaction service and dentist's service in terms of the solving the economic burden: and the entire variables in terms of dissatisfaction elements showed a similar level of significant difference 4. in regard to the satisfaction of dental service and the change of the recognition of prosthesis patients, it was revealed that the level of dental prosthesis satisfaction of the respondents was closely related to the dentist's service, staffs' service, and dental facilities' service. Finally, looking at the influence of the dental service on the treatment result, satisfaction, word of mouth, revisit and the overall satisfaction level, it was revealed that they had a great impact on the prosthesis satisfaction service.

• 한국보건간호학회지
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• 제5권2호
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• pp.27-35
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• 1991

This study was conducted to provide information of effective student guidance in nursing education. The sample consisted of 103 nursing students in the area of Seoul and 143 students in Cholla Province. Data were collected by using a questionnaire, which consisted of items about personnal campus life and their major. The results are summarized as follows: 1. There was on significant difference in campus life adaptation on nursing students between Seoul and local areas. 2. In Seoul area, there was no significant difference in campus life adaptation according to academic years. In local area, significant difference was revealed in the academic years. The scores of campus life adaptation were possitively correlated with their academic years. 3. The variables which can be explained in the regional difference were social recognition of nursing and a family atmosphere. In conclusion, the results of the study indicate that, in Seoul and local areas, the personal and educational backgrounds of campus life adaptation were equalized. In addition, it is very important that the counselling on choice of major should be provided to high school students.

• The Journal of Korean Physical Therapy
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• 제25권5호
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• pp.266-272
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• 2013

Purpose: The purpose of this study was to determine the influence of whole body vibration (WBV) exercise on balance and lower extremity muscle activity according to different intensity of vibration in stroke patients. Methods: Thirty subjects were randomly divided into three groups: experimental group II (n=10), III (n=10), and control group I (n=10). Each subject was exposed to three WBV conditions, as follows: 1. no WBV (group I), 2. 10 Hz (group II), 3. 30 Hz (group III) in semi squat position. The exercise program was conducted for six weeks (five times per week; 16 minutes per day). Subjects were measured on balance (limited of stability: LOS) and lower extremity muscle activity. Results: Significant difference in balance and lower extremity muscle activity was observed in the experimental group (II, III), compared with the control group (I). Results of post-hoc analysis, showed a significant difference in balance (LOS) in on group II and group III compared with group I, but no significant difference in on group II compared with group III, and a significant difference in lower extremity muscle activity in on group II and group III compared with group I, and a significant difference on in group II compared with group III. Conclusion: WBV exercise may be helpful in improvement of balance and lower extremity muscle activity in stroke patients.

• 한국강구조학회 논문집
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• 제12권3호통권46호
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• pp.303-315
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• 2000

본 논문에서는 일반화된 21개 강성 매트릭스의 독립 변수를 모두 사용하였고 비등방성 3차원 탄성체의 지배 방정식 및 수치 해석 근사식을 유도하였다. 일반화된 3차원 해석은 2차원 해석의 제한성을 극복하는 정밀해를 보여줄 수 있으며, 두꺼운 보나 판, 또는 쉘에서 전단 변형 효과에 의한 처짐의 증가 효과를 더욱 정밀하게 해석할 수 있다. 따라서 본 논문은 3차원 비등방성 탄성체에 대하여 다양한 경계조건에 따른 유한 차분식을 유도하였으며 이를 전산화하여 해석 프로그램을 개발하였다. 특히, 본 논문에서는 자유경계조건에 대하여 개선된 유한차분법의 적용 방식을 제시하였다. 또한 탄성체의 각 방향 자유경계면에서 경계조건을 해결할 수 있는 일반화된 방식을 제시하였다. 몇가지 수치예제를 통하여 이러한 유한차분 경계처리 방식에 의한 비등방성 3차원 탄성체 해석의 타당성 및 거동을 분석하였다.

• 감성과학
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• 제12권4호
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• pp.403-410
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• 2009

본 연구의 목적은 무선 통신 사업자 간에 휴대폰에서 제공되는 휴대폰 벨소리 사운드의 음질차이가 있는지, 있다면 어느 요소에서 발생하는지를 조사하는 것이었다. 선두 무선 통신 사업자나 휴대폰 제조사가 가지는 브랜드의 영향 요소를 배재하고 음질의 차이가 생기는 요소들을 찾아내기 위한 일련의 실험이 계획되었다. 무선 통신 사업자, 휴대폰 제조사, 휴대폰 모델, 특정 장르, 음원 콘텐츠 제작자 등 음질의 차이가 발생 할 수 있는 요소들을 테스트 하였다. 연구결과 휴대폰을 통해 제공되는 벨소리 사운드는 무선 통신 사업자별로 음질 차이가 존재하는 것으로 조사되었다. 음질의 차이는 콘텐츠 및 휴대폰의 차이에서 발생하며, 동일휴대폰 모델의 경우에도 무선 통신 사업자 모델별로 음질의 차이가 발생하는 것을 알 수 있었다. 또한 콘텐츠를 제공하는 음원 제작사 별 음질의 차이도 있는 것으로 나타났다. 음악 장르에 대한 음질의 차이는 명확하게 나타나지 않았다. 제한된 샘플을 이용한 실험의 한계를 보완하기 위하여 휴대폰 제조업체의 사운드 전문가를 통한 인터뷰가 시행되었다. 인터뷰 결과 제품 가격의 차이에서 오는 스피커 단품 및 미디, 앰프 등 하드웨어적 차이가 음질에 영향을 끼치는 것으로 조사되었고, 부품 및 기구의 튜닝 또한 중요도를 갖는 것으로 조사되었다.

• 대한통합의학회지
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• 제1권2호
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• pp.37-46
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• 2013

Purpose : The purpose of the research was to analyze foot pressure, foot temperature, and correlation between foot pressure and foot temperature to grasp impact on foot pressure and body temperature distribution chart depending on functional difference of leg length. Method : After measuring leg length, put 15 students whose functional difference of leg length was over 10mm to difference group and 15 students whose functional difference of leg length was under 5mm to normal group and categorize soles of foot into 6 sections of hallux head, 1st metatarsal head, 2-4 metatarsal head, 5 metatarsal head, lateral heel, and then measure by foot pressure analyzer to analyze characteristic of pressure distribution and classify into front of the lower leg, back of the lower leg, soles of foot and measure by body temperature analyzer to analyze by checking body temperature. Result : Weight difference depending on foot pressure and body temperature was bigger when functional difference of leg length was bigger, and it could be confirmed that foot pressure and body temperature of short leg side were higher than those of short leg side. Thus, if difference exists in leg length, weight load on short leg side increases which results in higher foot pressure and body temperature, therefore enabling an assumption that mechanical problem will occur in short leg. Conclusion : When functional leg length inequality, weight bearing and pressure was getting high as a result, temperature was getting high in short leg.