• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.99-104
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• 2006

A semi-Lagrangian finite element scheme with objective time stepping algorithm for solving viscoelastic flow problem is presented. The convection terms in the momentum and constitutive equations are treated using a quasi-monotone semi-Lagrangian scheme, in which characteristic feet on a regular grid are traced backwards over a single time-step. Concerned with the generalized midpoint rule type of algorithms formulated to exactly preserve objectivity, we use the geometric transformation such as pull-back, push-forward operation. The method is applied to the 4:1 planar contraction problem for an Oldroyd B fluid for both creeping and inertial flow conditions.

• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.7-15
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• 1998

An upper bound elemental technique(UBET) program has been developed to analyze forging load, die-cavity filling and effective strain distribution for flash and flashless forgings. The program consists of forward and backward tracing processes. In the forward program, flash, die filling and forging load are predicted. In backward tracing process, the optimum dimensions of initial billet in conventional forging are determined from the final-shape data based on flash design. And the analysis is described for merit of flashless precision forging. Experiments are carried out with pure plasticine billets at room temperature. The theoretical predictions of forging load and flow pattern are in good agreement with the experimental results.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.70-76
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• 2000

In the charge system, a contact type-convenient-charging method is insufficient because of the contact failure around moist environment and troublesome question to put in and pull out. For the solution of this problem, an electromagnetically coupled non-contact charger for the rechargeable cell is proposed using ZVS multi-resonant forward converter with synchronous rectifier. In this paper coupling coefficient(k), leaking inductance, coupling inductance and resonant frequency are observed for the air gap. By using the observed value, this circuit is designed and implemented. This proposed circuit is simulated by the PSPICE and experimented. The stress of a main switch and the output power are measured.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.356-359
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• 2006

This paper presented the power losses comparison results with the Active clamp Forward, the Asymmetrical half bridge and the Two transistor forward converters. To estimate for conduction losses in the converters, the steady state analysis regard to parasitic resistance and current effective values for main parts of converters was derived. In addition, the theoretical efficiency for the converters with input voltage 400V, output voltage 12V and maximum power 480W was discussed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1998년도 강연회 및 연구개발 발표회 논문집
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• pp.63-72
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• 1998

This study Is on the performance prediction and design of sirocco fan. Slip coefficient is very important factor for the performance analysis of centrifugal-type fan. Because generally used slip coefficient equations of backward curved centrifugal fan are not appropriate for forward curved sirocco fan, in this study a proper slip coefficient equation for sirocco fan is suggested. Using this equation performance prediction program for sirocco fan is composed and also included the total noise prediction that include turbulent noise at the fan Inlet and boundary layer noise. A comparison between the values obtained from performance prediction program and experimental values shows that the program predicts the sirocco fan performance in a practical rate.

• The Journal of Korean Physical Therapy
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• 제12권3호
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• pp.339-347
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• 2000

To elucidate pressure pain threshold of pericranial muscle due to involuntary. the effect of 30 min or forward head position(FHP) was studied in 20 patients with episodic tension-type headache and in 20 control without headache. Pressure pain thresholds were recorded before and after the FHP. and evaluated by pressure algometry. Thresholds increased in the patients and control after FHP. Relation between thresholds in patients anf control before FHP were not significant differences, but thresholds increased in patients after FHP. So, involutary muscle contraction due to FHP may be effect pressure pain threshold or pericranial muscle.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1300-1302
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• 2000

In the charge system, a contact type-convenient-charging method is insufficient because of the contact failure around moist environment and troublesome question to put in and pull out. For the solution of this problem, an electromagnetically coupled non-contact charger for the rechargeable cell is proposed using ZVS multi-resonant forward converter. In this paper magnetizing inductance, leakage inductance and coupling coefficient, k are observed. By using the obserbed value, the proposed circuit is simulated by the PSPICE and implemented and the peak voltage of switch and output power are measured.

• 대한치과보철학회지
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• 제16권1호
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• pp.13-16
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• 1978

The author conducted an experiment of recording side shift of the lateral mandibular movement and analyzing the timing of the side shift on the twenty-two non-functioning side condyles. As a result, clinically useful informations were obtained. The findings were as follows: 1. On all the non-functioning side condyle path, during the first four millimeters of forward movement, the change in the rate of the mandibular side shift was observed. 2. Band E types of the mandibular side shift ,which have shown a distinct rate of immediate side shift were fifteen condyles, and C type of the mandibular side shift which has shown the greatest rate of the side shift occurs early in the first four millimeters of forward movement was seven condyles. 3. A and D types which have shown generally progressive and distributed nature were not observed.

• 인지과학
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• 제1권1호
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• pp.145-164
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• 1989

본 논문은 언어습득 초기단계의 아동이 모국어의 주요분기방향(principal branching direction)에따라 종응사규칙을 습득한다는 최근의 연구결과에 의거한다(Lust,1986).이 연구에 의하면,가령 한국어는 좌행 분기어임을 한국아동은 죄행생략형을 선호할 것이라고 한다.이가설을 시험하기 위해 서울에 거주하는 4:1-9:7의 96명의 아동을 모방유도실험으로 개별연구하였다.문장유형으로는 중복형,우행생략형 및 좌행생략형 등이 이용되었다.실험결과,Lust의 예측과는 달리 좌행분기어인 한국어 습득아동도 우행분기어인 영어습득아동처럼 우행 생략형을 좌행생략형보다 용이하게 일찍 습득하고 있음을 발견하였다.이것은 인간에게 분기방향과 같은 문법적 요소에 상관없이 선행사가 공조응사보다 앞서 언급되는 형태(우행생략형) 를 선호하는 인지적기재가 있음을 시사한다고 사려된다.

• 한국운동역학회지
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• 제18권3호
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• pp.71-82
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• 2008

본 연구의 목적은 $20^{\circ}$ 경사로에 서 앞 뒤 보행 동작 시 지면반력 형태를 비교 분석하고자 한다. 본 연구를 위해서 두 대의 지면 반력기를 통해 전 후, 좌 우, 수직 지면반력값, 최대값, 최소값, 평균값 압력 중심 변위, 부하율과 감소율을 측정하였다. BD보행 시 RTO 시점에서 수직 지면반력값이 FU 보행에 비해 유의하게 높은 수치를 보인 반면, $RHC_2$ 시점에서는 더 낮은 수치를 보였다. 이는 보행 동작의 차이와 보행 시 발목과 무릎의 위치 변화, 무게 중심의 변화가 지면 반력의 형태에 직접적인 영향을 미치는 것으로 판단되어진다. 전 후 압력중심변위는 하향 보행 시 상향 보행에 비해 낮은 변화를 보였는데 이는 하향 시 생기는 불안정성을 상쇄하기 위해 더 강한 제동력이 발생되어 진 것으로 사료되어 진다. BD보행 시 부하율이 다른 보행에 비해 낮은 것을 알 수 있는데 이러한 결과를 통해 등산로에서 후방 보행 동작이 하지 근골격계에 지속적인 스트레스를 감소시켜 상해를 예방할 수 있는 방법으로 제시될 수 있을 것이다.