• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.03a
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• pp.161-176
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• 2002

Collision avoidance is the most important part of a small vessel. Small and mediurn sized ships are surprisingly poor targets for radar reflection and are frequently in danger of being overrun by large vessels, even under good condition of visibility. One of the best way to prevent collisions at sea is to use as large and well designed a radar reflector. Thus, RCS(Radar Cross Section) increase is key element in the design of radar reflector. Radar Reflectors are normally classified into active-type and passive-type. In this paper, the RCS increase methods for passive-type reflector through shaping are explained, and analyzed with RCS performance test by computer simulation. As results from analysis, It is shown that the effective diameter of radar reflector is over 10 λ to provide a return above the threshold RCS of 25m$^2$, lower limit of detectability using X-band radar in a moderate sea.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.2
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• pp.185-192
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• 2017

In this paper, we reviewed major design parameters for a solid type of deployable antenna and its structural design. We performed modal analysis for a single reflector panel made of aluminum and CFRP (carbon fiber reinforced plastic) to confirm the appropriateness of selected materials. We then predicted the elastic modulus of CFRP using the principles of unidirectional composite elasticity stiffness predictions such as the ROM (Rule of Mixture) and HSR (Hart Smith 10% Rule). To optimize the shape of the antenna reflector, a structural stiffness analysis was performed using derived numerical optimization factors. Six structural stiffness analyses were performed using the constructed experimental design method. The resulting optimal shape conditions are proposed to meet the structural stiffness requirements while minimizing weight.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.3
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• pp.347-350
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• 2009

In this study, it was studied about the improved road light design for drivers and pedestrians using forward or reverse ray-tracing method. Many of conventional road lights are not suitable for drivers and pedestrians because it has some serious problems such as glare effect or randomicity of illuminated areas. It was oriented from customary design method which was pointed at simple target such as luminance or electrical power. But it was not truth any more that the high luminance or electrical power consumption mean more bright and good road light. We studied ray-tracing method for road light reflector design to get the several goals. It means that good road light has easy for drivers and pedestrians eyes and illuminating objects on the road clearly. So, we set the design targets such as uniformity on the road area per one road light, shading angles and continuous luminance uniformity on the long distance road. We designed ideal road light conditions using ray-tracing method. We set the height of drivers and pedestrians eyes and calculated design guideline to make above design targets. Then we designed road light reflector using reverse ray-tracing method. And we achieved same luminance on the road almost half power consumption because we reduced loss of light. We achieved ideal design guide as 75 degrees of shading angles and 0.5 of luminance uniformity on the road area. It is superior than conventional road light ability such as 0.35 of luminance uniformity of 400 watts power consumption lamp. Finally, we suggested reflector design for 250 watts power consumption CDM Iight source.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.1
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• pp.97-104
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• 2014

Recently infrared cameras have been widely used to diagnosis degradation status of the power substitution system. At the place of high magnetic field, however, electronic parts of infrared camera take a place problem that is not reasonable working due to high magnetic field. In this paper, technique of design for reflector is proposed to perform degradation diagnosis without damage of infrared camera in a power substation system including the rectifier that is able to impact to the infrared camera by high magnetic field.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1178-1182
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• 2011

The best methods for distribution controled of LED lighting fixtures is control to designed LED chip array, lens and reflector. However, lens design need distribution design to reflector for low-wattage LED lighting because of difficulty of production and reduction of light efficiency. In addition, it needs maximize of thermal performance to improve the efficiency and reliability of device. As a result, for the height of reflector 40[mm] and Inclination 25[$^{\circ}$], we can see the best distribution properties, and, in the thermal properties, junction temperature MCPCB 62.9 [$^{\circ}C$], FR4 PCB 89.6 [$^{\circ}C$], FR4 PCB from Via-hole is 63.1 [$^{\circ}C$]. it may improve for thermal properties for makes the Via-hole.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1780-1785
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• 2015

In this paper, the adaptive particle swarm optimization (APSO) algorithm is employed to design a gain-enhanced antenna with a reflector for energy harvesting. We placed the reflector below the main radiating element. Its back-radiated field is reflected and added to the forward radiated field, which could increase the antenna gain. We adopt the adaptive particle swarm optimization (APSO) algorithm, which improves the speed of convergence with a high frequency solver. The result shows that performance of the optimized design successfully satisfied the design goal of the frequency band, gain and axial ratio.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1497-1498
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• 2008

LED 조명기구의 최적 배광제어를 위한 방법으로 Reflector 와 Lens를 설계하여 빛을 제어한다. 그러나 Lens설계는 제작의 어려움과 광효율의 감소로 인하여 2차적으로 사용되는 방법이다. 이를 해결하기 위하여 본 논문에서는 Reflector를 이용한 배광 설계를 최적화하여 경제적인 제작이 가능 하도록 Photopia2.0을 이용하여 설계하였다. LED 각각의 개별 반사판과 모듈 전체 적용된 반사판을 적용하여 각 형태별 특징을 도출하였다.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.315-316
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• 2006

The modulation bandwidth, wavelength chirp of directly modulated coupled-ring reflector laser diode have been investigated using time-domain modeling. For a specific design, the modulation frequency could be 6 GHz and the frequency chirp could be in the range of $120^{\sim}200$ MHz/mA.

• Korean Journal of Optics and Photonics
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• v.30 no.5
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• pp.197-203
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• 2019

In this paper, we studied a reflector design that can improve the illuminance uniformity when using a xenon flash lamp in the photonic sintering process. To achieve complete sintering of substrates in the irradiated area, the light efficiency and illuminance uniformity were set to target performance. Existing elliptical reflectors or parabolic reflectors make it easy to satisfy the target light efficiency, but have difficulty satisfying the illuminance uniformity. In this paper, a twin-concave feature has been added to the center of the parabolic reflector to satisfy the illuminance uniformity. It was confirmed that the illuminance uniformity of the parabolic reflector with a twin-concave feature was improved, compared to that of the traditional reflector.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.3
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• pp.1-6
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• 1999

SpeROD, the optical design program. is developed far specular reflectors of fluorescent luminaries. SpeROD can save much tirre when to design specular reflectors. SpeROD calculates conditions 2-dimensionally. The conditions for designing reflectors considered in this program are the intensity distribution, reflector type, and Tangent Spiral Design method. Using SpeROD, uniform intensity distribution type and bat-wing type reflectors are simulated in this paper, and alrrnn(T8) diarreter fluorescent lamp and lmnm width reflector are used for the setting. The sarre setting was simulated in FIElD, the intensity distribution prediction program. and the' result represented the intensity distribution and the efficacy simulated in SpeROD were satisfactory.actory.