• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.95-97
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• 2007

Large area flicker is one of the most annoying image defects, and it is an inherent characteristic of impulsively driven displays such as CRTs. Recently, LCDs have also adopted impulsive driving methods for improved motion picture quality, therefore LCDs can also show large area flicker. Existing metrics do not account for the non-linearity of human brightness perception. This paper presents an improved large area flicker metric to more accurately quantify large area display flicker performance.

• Bulletin of the Korean Chemical Society
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• 제16권3호
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• pp.256-260
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• 1995

Laser induced fluorescence spectra of OH produced from photodissociation of $H_2O_2$ at 280-290 nm in the gas phase have been observed. By analyzing the Doppler profiles, the anisotropy parameter($\beta$ =-0.7) and the center of mass translational energy of the fragments have been measured. The measured energy distribution is well described by an impulsive model. The excited state leading to dissociation is found to be of 1Au symmetry. The dissociation from this state is prompt and direct with the fragment OH rotating in the plane perpendicular to the O-O bond axis.

• 한국정밀공학회지
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• 제22권4호
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• pp.107-112
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• 2005

In this study, the dynamic analysis is performed fur predicting the transmitted force to flexible human body induced by prototype HIF(High Impulsive force) device operation, which is partially assembled by major parts. A beam-mass model and a shear-structure model are used for the flexible mount structure and their dynamic behavior are investigated by experimental results under rigid/flexible mount conditions using a general purpose device. From the test result of prototype device in rigid mount condition, the transmitted force to human body which can not be measured directly, is estimated based on the proved mount structure model.

• 한국해안·해양공학회논문집
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• 제33권6호
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• pp.257-264
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• 2021

본 연구는 완전비선형 Boussinesq 방정식 모델인 FUNWAVE-TVD 모델을 이용하여 비선형 불규칙파에 의한 해안구조물의 월파량을 산정할 수 있는 수치모형을 수립한 것이다. 여기서는 EurOtop(2018)의 월파량 산정 식 및 Goda(2009)의 경험식을 코딩하여 FUNWAVE-TVD 모델의 서브루틴으로 추가하고 수치모형을 수립하였다. 모형의 검증은 직립구조물에 대한 비선형 불규칙파의 월파량을 수치계산하고 EurOtop(2018)에 제시된 실험 결과와 비교하여 수행하였다. EurOtop 식에 의한 수치계산 결과는 비쇄파 조건의 경우 모든 상대여유고(Rc/Hmo) 구간에서 실험결과와 매우 잘 일치하였으며, 경험식에 의한 수치계산 결과는 R_c/H_mo < 0.8 구간에서는 실험 결과보다 과소평가 되었고 R_c/H_mo < 0.8의 구간에서는 실험 결과보다 과대평가 되었다. 쇄파조건의 경우 본 모형의 결과는 R_c/H_mo ≤ 1.35의 exponential curve나 R_c/H_mo > 1.35의 power curve 구간 모두에서 실험 결과를 잘 재현하였다. 따라서 본 수치모형은 직립구조형식의 호안구조물에서 비선형 불규칙파에 의한 월파량을 정도 높게 모의할 수 있음을 확인하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.719-724
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• 2002

Impact hammer is widely used as a convenient excitation tool in structural modal testing though, little is known about the dynamic characteristics of its impulse mechanism. Transmission of the impulsive force to the structure depends m the dynamic properties of the impact hammer as well as the stiffness of the tip. In this study an improved dynamic model of the impact hammer is proposed with the consideration of structure to be tested. The deformation masses of hammer tip and structure are as well as their contact stiffness. Numerical results show that this model is useful for the prediction of the impulse duration and the condition of rebounce..

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.731-736
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• 2002

Impact is the most common type of dynamic loading conditions that give rise to impulsive forces and affects the vibrational characteristics of mechanical systems . Since the real impact force and acceleration at the contact surface are measured indirectly through the sensors, the measured outputs can be a little different from the real impact responses. In this study, the contact force model based on the Hertz law is proposed in order to predict the impact force correctly. To investigate the influence of the position of the sensor attached to the impacting bodies, the two kinds of sensors were used. Finally, the contact force model obtained by drop test was applied to predict the impact force between the moving part and the stopper in magnetic contactor.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 추계학술발표논문집 2부
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• pp.785-787
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• 2010

It is well known that most power steering systems obtain the power by a hydraulic mechanism. Therefore, it consumes more energy because the oil power should be sustained all the times. Recently, to solve this problem the Electric Power System(EPS) or Motor Driven Power System(MDPS) has widely equipped in passenger vehicles. In this research the concurrent simulation technique for an EPS system with MATLAB/SIMULINK and a full vehicle model has been developed. The dynamic responses of vehicle chassis and steering system are evaluated. Then, a full vehicle model interacted with EPS control is concurrently simulated with an impulsive steering wheel torque input to analyze the stability of 'free control' or hands free motion for SUV. This integrated method allows engineers to reduce the prototype testing cost and to shorten the developing period.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.69-74
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• 1997

In this paper we derive relations which describe the geometry and kinematics of contact between the travelling wheel and stepped comb joint. From which we can obtain the impulse, impulsive force and its time interval due to travelling wheel impact which can not be taken from Carter's model or Newland and Cassidy's. The calculated transient responses of the comb joint structure to travelling wheel impact reveals that the proposed wheel contact model and Carter's give very similar results but Newland Cassidy's model make a quite different results from the others.

• 대한의용생체공학회:의공학회지
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• 제16권4호
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• pp.491-498
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• 1995

A numerical human head/neck model was constructed for analyzing the implication in decleration injuries. This model consists of nine rigid bodies representing the head, cervical vertebrae C1-C7, and T1. These rigid bodies were connected by intervertebral disks described by massless beam elements. Muscles and ligaments were also incoperated in the model represented by nonlinear spring and viscoblastic element respectively Agreement of the analytical kinematic response with the results of experimental data from a volunteer run was satisfactory. Moreover, possible injury estimation from the calculated moment, force variations in the disc, and force variation in ligaments matched well with clinical observations.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.88-91
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• 2009

For lightning currents, a grounding system shows the transient grounding impedance characteristics. A grounding system for protection against lightning should be evaluated by the transient grounding impedance, not it's ground resistance. The transient grounding impedance varies with the shape of ground electrode and earth characteristics as well as the waveform of lightning surge current. For the analysis and practical use of transient grounding impedance, the characteristics of transient grounding impedance should be analyzed theoretically and this paper suggests the theoretical analysis for the transient grounding impedance of counterpoise by using the distributed parameter circuit model. EMTP and Matlab are used to simulate the distributed parameter circuit model of counterpoise and the adequacy of the distributed parameter model of counterpoise is examined by comparing the simulated results with the measured results.