• 대한기계학회논문집
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• 제6권4호
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• pp.346-352
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• 1982

The vibration characteristics of hyoid gears are experimentally investigated with backlash and tooth mesh frequency varied. Experiments are performed with two types of gear sets; well-machined and over-lapped gears. Through the experimental works, a constant torque 0.8kg.m is applied to th gears and a pulse type of trigger signal synchronizing tooth contact is used to measure the tooth mesh frequency and to average the gear vibration signal in the time domain. The time averaged vibration signals are frequency analyzed by a digital signal analyzer. The experimental results show the vibration characteristics of the two different types of gears in relation to backlash amount and mesh frequency variations are well differentiated by harmonic amplitudes and their ratios, and peak-to-peak amplitude of the gear vibration.

• Journal of Power Electronics
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• 제8권1호
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• pp.35-50
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• 2008

A zero-voltage-transition (ZVT) pulse width modulated (PWM) converter is a PWM converter with a single main power switch that has an auxiliary circuit to help it turn on with zero-voltage switching (ZVS). There have been many ZVT-PWM converters proposed in the literature as they are the most popular type of ZVS-PWM converters. In this paper, the properties and characteristics of several types of ZVT-PWM converters are reviewed. A new type of ZVT-PWM converter is then introduced, and the operation of a sample converter of this type is explained and analyzed in detail. A procedure for the design of the converter is presented and demonstrated experimentally. The feasibility of the new converter is confirmed with results obtained from an experimental prototype. Conclusions on the performance of ZVT-PWM converters in general are made based on the efficiency results obtained from the experimental prototypes of various ZVT-PWM converters of different types.

• 동력기계공학회지
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• 제12권1호
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• pp.58-65
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• 2008

A method to test thin-walled tubes by guided ultrasonic wave is reported. The principle is that applicate two types of axially symmetric ultrasonic tube modes and "longitudinal" modes with particle displacement, which is coupled in axial and radial directions for transverse failures and torsional modes, oscillating in the circumferential direction only, for longitudinal failures. Both types of modes propagate along the tube in the axial direction. Therefore, a pulse-echo technique is possible. The pulses are excited and received at one end of the tube without contact electro-dynamic transducers. As soon as the tubes is put into a transducer coil at one end, the test of the whole tube can be accomplished in a few milliseconds. It is not necessary to rotate and transport the tubes during the test.

• 한국한의학연구원논문집
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• 제5권1호
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• pp.101-110
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• 1999

In Sasang constitutional medicine, the classification of Sasang constitutional types (Tae-Yang, Tae-Eum, So-Yang, and So-Eum) is important for the treatment. There are some problems with the methods used for classifying Sasang constitutional types; old methods such as pulse-palpation are not considered objective and recent methods such as immunohematology are considered expensive, painful and time-consuming. To overcome these problems, a body measurement and finger prints analysis were performed. The purpose of this study was to determine whether the palm prints and the palm creases could be helpful in classifying Sasang constitutional types. Thus, we looked for characteristics of the palm prints and the palm creases according to Sasang constitutional types. Before analyzing the palm prints and palm creases, 760 Korean (465 males, 295 females) were surveyed using two kinds of questionnaires for classifying Sasang constitutional types. As there were no Tae-Yang individuals, we were only able to identify the characteristics of the palm prints and the palm creases for Tae-Eum (288 persons), So-Yang (193 persons), and So-Eum (279 persons) individuals. In this study, the terminal points of D, closed crease, and open crease seemed to be helpful in classifying Tae-Eum and So-Eum individuals. Terminal point 11 and closed crease were frequent in Tae-Eum individuals; whereas, terminal point 7 and open crease were frequent in So-Eum individuals. Therefore, the palm prints and the palm creases seem to contribute to the classification of Sasang constitutional types.

• 응용통계연구
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• 제19권2호
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• pp.203-215
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• 2006

최근 한의학에서는 인체를 8가지 체질로 나누는 8체질의학에 대한 관심이 높아지고 있다. 그런데 8체질은 맥진에 근거하여 판별되므로, 8체질의 판별 및 병증의 치료를 표준화시키기 위해서는 객관적인 8체질의 특성을 찾아내어 이것을 표준화시키는 일이 절실하다. 본 연구에서는 맥진을 통하여 8체질로 분류된 후 8체질 침법에 따라 치료 중인 남자 환자들의 신체적 특징과 증후 등을 설문을 통하여 문진하였다. 그리고 일원배치 분산분석법에서 유의한 문항들에 대하여 다중비교법을 이용하여 8체질 사이의 평균 차이를 표로 나타내었다. 이 분석에서 유의하게 나타난 문항들은 실제의 진단 및 치료에서 관찰되어온 8체질 특성과 잘 일치하고 있었다.

• 대한한의학원전학회지
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• 제28권1호
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• pp.35-53
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• 2015

Objectives : In order to find how reference books of Yi Xue Ru Men reflect the classification and criterion for low back pain(LBP). Methods : From reference books of Yi Xue Ru Men, select the texts on classification and criterion for LBP. Results : According to the causes of LBP, Chao Yuan Fang(巢元方) in Sui Dynasty assorted to 5 types of LBP at the very first. Chen Wu Ze(陳無擇) in Song Dynasty made 7 divisions by external, internal, and non-external, non-internal causes. According to the pulse of LBP, Yan Yong He(嚴用和) first categorized 4 groups, Zhu Zhen Heng(朱震亨) added another 4 groups. Aside from this standard, Zhu(朱震亨) adopted the cause standard. Depending on Yunqi(運氣), Lou Ying(樓英) classified 5 types. But his classification had been not adopted by any TCM books. According to symptom of 6 varieties(六變), Zhang Jie Bin(張介賓) assorted external(表), internal(裏), deficiency(虛), sufficiency(實), cold(寒) and heat(熱), add 2 groups besides them. But his categorization did not reflect Yi Xue Ru Men. Li Chan(李梴), the author of this book chose causes and pulse classification standards that Zhu Zhen Heng had adopt. Conclusions : In the side of classification and criterion for LBP, Li Chan first divided 2 group, external and internal injury. After it he subdivided both groups to 10 subgroup. His classification is similar to Chen(陳無擇)'s, but actually followed the classification for external and internal injury that was invented by Li Dong Yuan(李東垣).

• 한국안전학회지
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• 제27권3호
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• pp.36-41
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• 2012

Electrical Connections often cause fires due to poor contact. Occurrence rate of these fires tends to increase annually. The reason why poor contacts occur is often because it is the low mechanical pressure at the contact points. A typical connection method using mechanical pressure is a screw terminal type. This study reviewed these poor contact cases in the screw terminals. In order to get reproduction of such cases, two types of experiments were conducted. the first one was conducted under the normal contact condition, and the other one was conducted under the poor contact condition that screw terminal of breaker was loosen and did not meet the requirements of toque value. In both types of experiments, compulsory vibration was adopted as a variable to aggravate poor contacts. Each of various current values(4.5A, 9.0A, 13.5A) is input. In these experiments, relationships of a contact, electrical signal such as current and electric pulse by ZCT and thermal characteristics according to vibration effect are analyzed. The suggested data and results in this study provide the useful resources helping to investigate fires due to poor contact, and they develop the detector for poor contact and finally reduce the electrical fire occurrence rate.

• 대한간호학회지
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• 제32권2호
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• pp.265-276
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• 2002

This study was to identify the trends and contents of imagery interventions and to evaluate the effects of imagery interventions by using meta-analysis. Method: The materials used for this study were 15 imagery intervention studies carried out from Jan. 1995 to Dec. 2001. The studies were analyzed and evaluated in different categories: 1) types of dependent variables 2) types of imagery 3) interval of imagery 4) total duration of imagery 5) sample characteristics 6) intervention method. Result: 1) Behavioral imagery was more prevalent than dynamic imagery. There were wide variations in duration, and interval of interventions. Imagery intervention had moderate effects on psychological variables (state of anxiety, depression & and stress etc.) and had moderate to large effects on physiological variable(pulse rate, cortisol etc.). Behavioral imagery had larger effects than dynamic imagery. Imagery applied to the public had larger effect on decreasing the state of anxiety and stress than applied to the patients. But imagery applied to the patients had a larger effect on decreasing depression than applied to the public. The imagery intervention method by using the individual approach had greater effect than group approach method. Conclusion: These results of this study will be used to guide the development of imagery interventions to nursing practice. Also, various types of imagery interventions need to be developed based on the characteristics of nursing practice.

• 사상체질의학회지
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• 제21권3호
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• pp.39-47
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• 2009

1. Objectives: In order to classify an individual into four constitution type, an oriental medical doctor utilizes various information such as face, pulse, voice, and questionnaire. When only one type of information is used, one's constitution may not be decided correctly. 2. Methods: In this paper, we propose a novel four constitution types classifier using facial images which classifies subjects into indecision group as well as Taeumin, Soeumin, and Soyangin. 3. Results: Experimental results show that it increases the classification rate though the decision rate is rather decreased, which is more effective and reliable than conventional classifiers without indecision. 4. Conclusion: For the effective classification, we have found that it is more useful to add an indecision group which requires more information to be properly classified into one constitution type.

• 한국초전도ㆍ저온공학회논문지
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• 제20권1호
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• pp.19-22
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• 2018

The thermal and electrical properties of the conductor are critical parametersfor the design and optimization of the superconducting magnet. This paper presents simulation code to analyze electrical and thermal stability characteristics of the second generation (2G) high-temperature superconductor (HTS) by varying copper stabilizer thickness. Two types of commercial 2G HTS coated conductor tapes, YBCO and GdBCO were used in this study. These samples were cooled by Liquid Nitrogen ($LN_2$) having boiling at 77.3 K and an equivalent electrical circuit model for them is choosen and analysed in details. Also, an over-current pulse test in which a current exceeding a critical current was performed. From the simulation results, the influences of the copper stabilizer thickness on the stability characteristics of these samples are presented.