• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.80-83
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• 1994

A Littman type dye laser oscillator inserted a wedge prism was constructed. Accurate frequency tuning was achieved by the rotation of the wedge prism instead of the tuning mirror. Frequency tuning rate was about 20 GHz/deg. and the synchronous tuning of 70 GHz without mode-hop was achieved. ieved.

• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.295-302
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• 2022

In this paper, a wedge prism application method was studied to design a full-high-definition (FHD)-class high-resolution flexible endoscope. In the case of the conventional flexible endoscope optical system, the F number is made large or a liquid lens is applied to obtain the same imaging performance in a wide depth of field. However, there is a problem in that the diameter of the optical system increases because an additional light guide and equipment are required. To solve this problem, two wedge prisms were applied to the flexible endoscope optical system to adjust the image distance for each object distance. First, two wedge prisms were symmetrically placed on the designed endoscopic optical system. An image distance satisfying the target imaging performance according to each objective distance was derived. Next, the wedge prism decenter value for controlling the image distance was derived. By combining these two data, a wedge prism decenter value that satisfied the target imaging performance at each object distance was applied in multi configurations. As a result of the optimal design applied with the wedge prism, a target imaging performance of more than 20% of the modulation transfer function for a resolution of 178 cycles/mm was satisfied in the entire depth of field of 100 mm-7 mm.

• Laser Solutions
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• v.10 no.3
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• pp.11-14
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• 2007

A trepanning optics is the optical system which makes focus laser beam rotate and incline to the material processing surface. The trepanning optics is used in order to improve the quality of laser drilling process and control the taper of drilling diameter. In order to make trepanning optics, we can use the eccentricity of lens, scanner using two mirror, dove prism, or wedge. Among these method, in this paper wedge is used for trepanning optics. The wedge trepanning optics has advantage on the high speed of rotation. In this paper, we design the wedge trepanning optics using ray tracing. ements and engine design variables of system to satisfy the customer's requirements.

• Therapeutic Science for Rehabilitation
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• v.6 no.2
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• pp.37-45
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• 2017

Background: The presence of visuospatial impairment can make patients slow functional recovery and impede the rehabilitation process in TBI patients. Objective: The aim of this study is to investigate effects of prism adaptation treatment for functional outcomes in patients following traumatic brain injury. Methods: The subject received prism adaptation treatment for 2 weeks additionally during traditional rehabilitation for 4 weeks. The Patient has prism adaptation treatment while wearing wedge prisms that shift the external environment about $12^{\circ}$ leftward. The patient received 10 sessions, 15-20min each session. Outcome measures were visuospatial deficit(line bisection, latter cancellation), Visual and spatial perception(LOTCA-visual perception and spatial perception), motor function of upper extremity(FMA U/E; Fugl-Meyer motor assessment upper extremity, ARAT; Action research arm test), balance(BBS; Berg Balance Scale), mobility(FAC; Functional ambulation classification) and functional level(FIM; Functional independent measure). All Assessments took place on study entry and post-treatment assessments were performed at discharge from the hospital. Results: After prism adaptation, the visuospatial impairment scores improved as indicated in the line bisection(-15.2 to -6.02), latter cancellation(2 to 0) and LOTCA- spatial perception scores(7 to 9). The upper motor function improved as indicated in the scores of affected FMA U/E(21 to 40) and ARAT(4 to 22). Ambulation and balance improved as indicated in the BBS scores(25 to 38) and FAC scores(0 to 4). ADL function improved as indicated in the FIM total scores 54 to 70(motor 34 to 61, cognition 20 to 29). Conclusion: Prism adaptation did improve functional level such as motor functions and ADL abilities in TBI patient. Further research is recommended.

• Journal of the Optical Society of Korea
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• v.12 no.1
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• pp.25-30
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• 2008

The optical performances of 15-inch edge-lit backlight were simulated by using a Monte Carlo ray-tracing technique. The backlight model was built by combining a wedge-type light guide plate, a diffuser sheet, a tubular fluorescent lamp with a lamp reflector, and two crossed prism sheets. Angular distributions of the luminance on each optical component obtained from simulation were consistent with those obtained from experiments on a real 15-inch backlight. The constructed backlight model was used to evaluate the optical performances of a micro-pyramid film. It was found that the on-axis luminance gain on the pyramid film is higher than that on one prism film but much lower than that on the two crossed prism films. These results suggest that a reliable simulation model can be used to develop new hybrid films and to optimize the optical structure of edge-lit backlight in order to reduce the developmental period.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.2270-2275
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• 2008

수문학적 하도추적법의 하나인 Muskingum 모형은 미 육군공병단(U.S. Army Corps of Engineers)에 의해서 미국 Ohio 주의 Muskingum 유역에 홍수조절계획으로 처음 사용되었으며 모형의 구조 및 입력자료의 단순성에 비하여 비교적 우수한 결과를 모의할 수 있는 것으로 알려져 있다. 1938년 McCarthy에 의해서 개발되었고 구간내 총저류량은 prism 저류와 wedge 저류로 구분하여 prism 저류는 유출량에 wedge 저류는 유입량과 유출량의 차에 직접 비례한다는 가정하에 추적식을 개발하였다. 이후 지속적인 연구가 이뤄져 1985년 O'Donnel은 측방유입량(lateral inflow)을 상류단의 유입량에 비례하는 형태로 3-매개변수 muskingum 모형을 제안하여 추적계수의 결정을 선형대수(linear algebra)에서 동차(homogeneous)연립방정식 해를 구하는 Cramer 법칙인 matrix 기법을 적용하였다. 본 연구에서는 홍수사상으로부터 측방유입량이 고려되고 추적계수 결정에 있어서 직접 계산이 가능한 O'Donnel(1985)이 제안한 3-매개변수 muskingum 모형을 적용하였다. 추적계수들의 결정은 직접 matrix 기법을 적용하였고 적용대상은 낙동강 유역의 낙동 지점을 상류단으로 구미 지점을 하류단으로 선정하였다. 홍수사상은 낙동강 유량측정 조사사업 2005년${\sim}$2007년 보고서에 수록된 수문자료를 선정하여 관측치와 계산치를 비교하였고 홍수사상에 적용하여 수문곡선을 추정하였으며, 각각의 매개변수가 추적구간에 어떠한 영향을 미치는지 변수간의 관계를 분석하였다. 또한, 관측치와 계산치의 적합도 검증은 평균제곱근오차(root mean squar error; RMSE)와 모형 효율성 계수(model efficiency; ME)를 산정하여 분석하였으며, 하도 구간내 저류량은 대상구간에 대한 유입량과 유출량의 가중합에 비례한다는 선형모형을 적용하였다.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.457-461
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• 2012

A real-time method to measure full field retardation near quarter wavelength is proposed. The circularly polarized beam passes through a sample with a large aperture. The measuring beam then goes through a quarter-wave plate and is then split by a Wollaston prism. An image with two sub-images is then detected by a high-speed image sensor. The full field retardation near quarter wavelength can be obtained in real time by processing the image. The measured retardation is independent of the fast axis angle of the sample and the fluctuation of the initial intensity. In experiments, a wedge waveplate is measured with different fast axis angle and initial intensity, and the full field retardations are acquired. The maximum and standard deviation of the full field retardation is $1.5^{\circ}$ and $0.4^{\circ}$. The validity of the method is verified.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.120-124
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• 2011

Predictive mathematical models were developed for predicting the kinetics of growth of Listeria monocytogenes in smoked salmon, which is the popular ready-to-eat foods in the world, as a function of temperature (4, 10, 20 and $30^{\circ}C$). At these storage temperature, the primary growth curve fit well ($r^2$=0.989~0.996) to a Gompertz equation to obtain specific growth rate (SGR) and lag time (LT). The Polynomial model for natural logarithm transformation of the SGR and LT as a function of temperature was obtained by nonlinear regression (Prism, version 4.0, GraphPad Software). Results indicate L. monocytogenes growth was affected by temperature mainly, and SGR model equation is $365.3-31.94^*Temperature+0.6661^*Temperature^{\wedge^2}$ and LT model equation is $0.1162-0.01674^*Temperature+0.0009303^*Temperature{\wedge^2}$. As storage temperature decreased $30^{\circ}C$ to $4^{\circ}C$, SGR decreased and LT increased respectively. Polynomial model was identified as appropriate secondary model for SGR and LT on the basis of most statistical indices such as bias factor (1.01 by SGR, 1.55 by LT) and accuracy factor (1.03 by SGR, 1.58 by LT).