• 아동학회지
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• 제35권2호
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• pp.63-84
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• 2014

The purpose of this study was to explore the effects of parental differential treatment and social support perceived by adolescents with siblings with special needs on their self-esteem and internalized problems. The subjects comprised one hundred 12- to 18-year-old adolescents with siblings with special needs. The major results of this study were as follows. First, there were significant differences in adolescents' self-esteem by participation in support programs for siblings of children with special needs. Second, there was no significant effect of parental differential treatment on adolescents' self-esteem. Third, there was a significant effect of social support (family, friends, and teachers) on adolescents' self-esteem. Fourth, there was no effects of paternal differential parenting on adolescents' internalized problems. However, there was a significant effect of differential maternal affection on adolescents' internalized problems. Fifth, there was a significant effect of social support, especially in terms of support provided by friends, on adolescents' internalized problems. In conclusion, social support and differential maternal affection both have an important role in adolescents' self-esteem and internalized problems.

• 한국전산구조공학회논문집
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• 제33권4호
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• pp.237-244
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• 2020

본 논문에서는 포스트 텐션으로 보강된 아웃리거 벽체의 부등기둥축소량 저감 효과를 확인하였다. 아웃리거 벽체 시스템을 사용할 경우 콘크리트 부재를 아웃리거로 사용하기 때문에 아웃리거 벽체의 장기거동도 고려해야 한다. 아웃리거 벽체은 깊은 보의 형태로 전단 응력이 지배적이기 때문에 전단 응력을 받는 콘크리트의 장기거동에 대한 이론 연구를 수행하였고 그 결과를 유한요소해석에 적용하였다. 아웃리거의 장기거동 고려 시 부등기둥축소량과 아웃리거에 작용하는 전단력을 확인하였으며, 설계 변수인 아웃리거의 두께를 변경해가며 해석하였다. 해석 결과 부등기둥축소량은 증가하고 아웃리거에 작용하는 전단력은 감소함을 밝혔으며 아웃리거의 강성이 작을수록 그 효과가 크다는 것을 밝혔다. 이후 아웃리거의 장기거동으로 인해 증가한 부등기둥축소량을 감소시키기 위해 포스트 텐션 공법으로 보강하는 방법을 제안하고 그 효과를 확인하였다. 프리스트레스 도입 직후의 프리스트레스 손실과 장기거동에 의한 프리스트레스 손실을 모두 고려하였다. 해석 결과 포스트 텐션 공법의 뛰어난 부등기둥축소량 저감 효과를 확인하였으며, 프리스트레스의 크기가 증가할수록 그 효과가 증가함을 밝혔다.

• 대한기계학회논문집A
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• 제31권2호
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• pp.231-236
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• 2007

This paper presents the effect of the center of the series on convergence in solving vibration problems by Differential Transformation Method(DTM) to the transverse vibration of the Euler-Bernoulli beam under varying axial force. The governing differential equation of the transverse vibration of the Euler-Bernoulli beam under varying axial force is derived. The concepts of DTM were briefly introduced. Numerical calculations are carried out and compared with previously published results. The effect of the center of the series on convergence in solving the problem by DTM is discussed.

• 대한수학회논문집
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• 제33권1호
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• pp.171-177
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• 2018

In this research paper considering a differential equation with impulsive effect and dependent delay and applied Banach fixed point theorem using the impulsive condition to the impulsive fractional functional differential equation of an order ${\alpha}{\in}(1,2)$ to get an uniqueness solution. At last, theorem is verified by using a numerical example to illustrate the uniqueness solution.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.141-148
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• 2000

In this study, differential settlements of adjacent structure and behaviour of ground during tunnel excavation and the effect of micropile installed to preserve differential settlement of structure are measured and analyzed by model test. In the test results, the effective range of reinforcement is suggested.

• 한국화재소방학회논문지
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• 제22권3호
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• pp.194-200
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• 2008

고층건물에서 급기가압 제연시스템과 같이 연기제어를 위해 제연구역에서의 압력차를 이용하는 제연시스템을 성공적으로 설계하고 운영하기 위해서는 건물내 압력형성에 영향을 미치는 건축적 요인들을 검토해야 하며 그중 큰 영향을 발휘하는 요인이 연돌효과이다. 본 연구에서는 고충건물의 피난환경과 제연시스템에 대해 연돌효과가 미치는 영향을 검토하기 위해서 여름과 겨울철에 각각국내 고층건물을 대상으로 급기가압 제연시스템을 가동하면서 피난계단, 부속실 및 거실에서의 압력변화를 측정하고 분석하였다. 연돌효과의 영향이 커지는 겨울철의 경우 급기가압 제연시스템이 가동되면 부속실에서 계단쪽으로의 누기현상과 연돌효과가 합쳐지면서 고층부의 계단실내 압력이 크게 상승하여 재실자가 대피를 위해 피난문을 열고자 할 때 문제가 발생할 수 있다.

• Structural Engineering and Mechanics
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• 제80권5호
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• pp.491-501
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• 2021

A difference in subgrade settlement between two rails of a track manifests as lateral differential subgrade settlement. This settlement causes unsteadiness in the motion of trains passing through the corresponding area. To illustrate the effect of lateral differential subgrade settlement on the dynamic response of a vehicle-track coupling system, a three-dimensional vehicle-track-subgrade coupling model was formulated by combining the vehicle-track dynamics theory and the finite element method. The wheel/rail force, car body acceleration, and derailment factor are chosen as evaluation indices of the system dynamic response. The effects of the amplitude and wavelength of lateral differential subgrade settlement as well as the driving speed of the vehicle are analyzed. The study reveals the following: The dynamic responses of the vehicle-track system generally increase linearly with the driving speed when the train passes through a lateral subgrade settlement area. The wheel/rail force acting on a rail with a large settlement exceeds that on a rail with a small settlement. The dynamic responses of the vehicle-track system increase with the amplitude of the lateral differential subgrade settlement. For a 250-km/h train speed, the proposed maximum amplitude for a lateral differential settlement with a wavelength of 20 m is 10 mm. The dynamic responses of the vehicle-track system decrease with an increase in the wavelength of the lateral differential subgrade settlement. To achieve a good operation quality of a train at a 250-km/h driving speed, the wavelength of a lateral differential subgrade settlement with an amplitude of 20 mm should not be less than 15 m. Monitoring lateral differential settlements should be given more emphasis in routine high-speed railway maintenance and repairs.

• 정보저장시스템학회논문집
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• 제2권1호
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• pp.85-90
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• 2006

In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential $3\omega$ method. Also, verification of differential $3\omega$ method has been accomplished with various proposed criteria. The target film for the measurement is 300 nm thick silicon dioxide which is covered with upper protective layer of various thicknesses. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. Since the verification of differential $3\omega$ method has not been conducted yet, we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential $3\omega$ method is verified to be reliable as long as the proposed preconditions of the samples are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between thickness of the upper protective layer and width of the heater line due to heat spreading effect.

• 한국항공우주학회지
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• 제49권7호
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• pp.589-592
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• 2021

프리코더와 CPM 변조기로 구성된 SOQPSK-TG는 수신기 구조를 단순화하기 위해 송신기에 차등 부호기를 추가한 차등 프리코더 방식이 텔레메트리 표준으로 채택되었다. 본 논문에서는 낮은 Eb/No에서 차등 부호기가 수신기 성능에 미치는 영향을 평가하였는데 컴퓨터 모의 실험한 결과에 의하면 차등 부호기가 없는 경우가 AWGN 채널에서 Eb/No 성능이 BER이 10^-1일 때 약 2dB, 10^-2일 때 약 1dB 더 우수하다.

• ETRI Journal
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• 제21권3호
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• pp.41-48
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• 1999

We have calculated differential reflection coefficient for isolated well structure of micro-scale, etched on dielectric surface. The differential reflection coefficient is computed using Green's second integral theorem. The purpose of our computation is to find a class of well profiles which give maximal diffusive scattering. To have such a maximal effect, we have concluded that the waist radius of Gaussian beam and its wavelength should be comparable to the well width and that well depth has to be larger than a wavelength. Exact calculation of differential reflection coefficients of dielectric surface with isolated structure on it may be used for the examination of dielectric surfaces and also in making simple but efficient diffuser.