• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.6
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• pp.27-34
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• 2011

In this paper, we propose an active 3D shape acquisition method based on photometric stereo using camera and flash on a smartphone. Two smartphones are used as the master and slave, in which the slave projects illumination from different locations while the master captures the images and processes photometric stereo algorithm to reconstruct 3D shape. In order to reduce the error, the smartphone's camera is calibrated to overcome the effect of the lens distortion and nonlinear camera sensor response. We apply 5-point algorithm to estimate the pose between smartphone cameras and then estimate lighting direction vector to run the photometric stereo algorithm. Experimental result shows that the proposed system enables us to use smartphone as a 3D camera with low cost and high quality.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.245-251
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• 2015

In this paper, we present a design of PWM-controlled driving device for backlights in LED systems. The system can control either the brightness of the entire screen of backlights of LCD driven by LED or illumination or contrast of each partial segment of the entire screen. The PWM-controlled driving device includes the shift register that shifts the series data according to the clock signal prior to the generation of parallel data. It is also is comprised of a number of registers, a number of counters, a number of comparators, and a number of synchronizing gates (producing the PWM-controlled signals). The proposed device for backlights in LED systems can generate the PWM-controlled signal with a high degree of resolution without the increase of clock frequency. It also contains the PWM-controlled circuit that disperses and restrains the quantized noise.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.128-134
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• 2015

The number of schools which have passed 30 years after the construction takes up 30% (5% falling to class D and E) in Korea. So, the offices of education across the nation conduct large works for the expansion, improvement and renovation of the school. But as the work takes a lot of time, the work is also conducted while the students are studying at the schools. The work at the school causes the noise, dust, vibration as the school often has the reinforced concrete structure. So, as the windows are closed to prevent the nuisance from hampering the education, the problems related to the illumination, ventilation, and control of humidity and temperature are give damages to students studying the school buildings. Actually, as the current renovation or expansion is conducted across the nation due to the implementation of the new education system and the resulting integration and construction of hub school, specialized school, meister school and it causes a lot of nuisance to the learning students and others, there are a lot of complaints from concerned people. Accordingly this study suggests the method of evaluating the factors which affect the learning environment such as the noise, dust or fine dust and reducing the nuisances to the level proper for the learning environment when the existing school is expanded, improved or renovated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.6
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• pp.445-454
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• 2001

The stochiometric mix of evaporating materials for the CuInSe$_2$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, CuInSe$_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy(HWE) system. The source and substrate temperature were 62$0^{\circ}C$ and 41$0^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of CuInSe$_2$ single crystal thin films measured from Hall effect fby van der Pauw method are 9.62x10$^{16}$ cm$^{-3}$ , 296$\textrm{cm}^2$/V.s at 293 K, respectively. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the CuInSe$_2$ single crystal thin film we have found that he values of spin orbit splitting ΔSo and the crystal field splitting ΔCr were 6.1 meV and 175.2 meV at 10K, respectively. From the photoluminescence measurement on CuInSe$_2$ single crystal thin film we observed free excition (Ex) existing only high quality crystal and neutral bound exiciton (D$^{\circ}$,X) having very strong peak intensity. Then, the full-width-at-half-maximum(FWHM) and binding energy of neutral donor bound excition were 7meV and 5.9meV, respectivity. by Haynes rule, an activation energy of impurity was 50 meV.

• Korean Journal of Remote Sensing
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• v.31 no.3
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• pp.255-265
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• 2015

Very high resolution (VHR) satellite imagery provide valuable information on urban change monitoring due to multi-temporal observation over large areas. Recently, there has been increased interest in the urban change detection technique using VHR Synthetic Aperture Radar (SAR) imaging system, because it can take images regardless of solar illumination and weather condition. In this paper, we proposed a texture-based urban change detection method using the VHR SAR texture features generated from Gray-Level Co-Occurrence Matrix (GLCM). In order to evaluate the efficiency of the proposed method, the result was compared, visually and quantitatively, with the result of Non-Coherent Change Detection (NCCD) which is widely used for the change detection of VHR SAR image. The experimental results showed the greater detection accuracy and the visually satisfactory result compared with the NCCD method. In conclusion, the proposed method has shown a great potential for the extraction of urban change information from VHR SAR imagery.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.5 s.108
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• pp.451-460
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• 2006

We have designed local exposure systems for long-time mice experiments in PCS and cellular frequency band(PCS: 1,762.5 MHz, cellular: 848.5 MHz). The fabricated systems are local exposure systems of carousel type, and 40 mice can be exposed at a time. In order not to give extra stress to the mice ender experiment, the systems were fabricated to meet the environmental conditions such as illumination, ventilation, noise etc. SAR measurement was performed using a temperature probe. Measurements at 3 points in the head of mouse cadaver and solid phantom were made, and it has been confirmed that the measurement results are in good agreement with the simulation results in the real exposure environment. The exposure systems are currently used for long-term mice experiments.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.1
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• pp.69-76
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• 2018

This study is to research technical measures for improving energy efficiency in the conservation and reuse of historic buildings focused on the recent research trends and case studies of the west. These measures are broadly classified into three types, the passive measures for saving energy and increasing comfort, the most cost-effective energy saving strategies, and the renewable energy sources. Firstly, the passive measures are divided into the elements and systems. The passive elements are awnings and overhanging eaves, porches, shutters, storm windows and doors, and shade trees. There are also the natural ventilation systems such as the historic transoms, roofs and attics to improve airflow and cross ventilation to either distribute, or exhaust heat. Secondly, the most cost-effective energy efficiency strategies are the interior insulation, airtightness and moisture protection, and the thermal quality improvement of windows. The energy efficiency solutions of modern buildings are the capillary-active interior insulation, the airtightness and moisture protection of interior walls and openings, and the integration of the original historic window into the triple glazing. Beyond the three actions, the additional strategies are the heat recovery ventilation, and the illumination system. Thirdly, there are photovoltaic(PV) and solar thermal energy, wind energy, hydropower, biomass, and geothermal energy in the renewable energy sources. These energy systems work effectively but it is vital to consider its visual effect on the external appearance of the building.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3C
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• pp.92-101
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• 2005

It is difficult to detect the accurate detection which leads the camera it moves follows in change of the noise or illumination and Also, it could be recognized with backgound if the object doesn't move during hours. In this paper, the proposed method is updating changed background image as much as N＊M pixel mask as time goes on after get a difference between imput image and first background image. And checking image pixel can efficiently detect moving by computing fixed distance pixel instead of operate all pixel. Also, set up minimum area of object to use boundary point of object abstracted through checking image pixel and motion detect of object. Therefore motion detection is available as is fast and correct without doing checking image pixel every Dame. From experiment, the designed and implemented system showed high precision ratio in performance assessment more than 90 percents.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.108-108
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• 2011

공동주택에서 2025년 정부가 추진하고 있는 Zero Energy 건축물 구현과 친환경에 대한 탄소배출 저감 문제로 재생에너지 생산시스템의 추가 적용은 반드시 필요하다. 따라서 공동주택 적용 및 활용성을 높일 수 있는 BIPV시스템 개발을 통하여 설치면적 확보와 세대 활용성을 높일 수 있도록 하는 것이 필요하다. 특히 거실 창호의 경우 주방향이 남향, 남동 또는 남서향으로 배치되어 태양광을 적용하기에 적합한 특성을 가지고 있다. 그러나 창호는 건물외피의 역할과 재실자가 조망과 정보취득을 얻을 수 있는 중요한 통로가 되기 때문에 단열 문제나 시야 차폐의 문제는 발생하지는 않도록 하는 것이 필요하다. 본 연구에서는 a-si타입 모듈 2개를 10% 투과율로 Bsck Coating 색상을 달리한 모듈과 c-si BIPV 모듈을 커튼월 창호시스템으로 개발, 일반 2중 창호시스템과 비교 평가를 위해 실제 Test bed 건물에 시공하여 시환경 및 실내 창측면 온도변화 측정 분석을 진행하였다. 현재 국내외 출시되고 있는 a-si see through 모듈은 10~30%의 투과율로 창 마감재로 대체가 가능하나 건축 환경(시환경,열환경)에 대한 분석은 전무한 상태이다. 본 연구에서는 시환경과 창유리면의 열 부하, 자외선, 적외선 차폐 및 가시광선의 투과율에 대한 평가와 Back Coating에 따른 색온도 평가를 통해서 a-si BIPV의 공동주택 세대 발코니 창호 적합성에 대한 검토를 진행하였다. 연구결과는 아래와 같다. ${\bullet}$ 실내조도는 청천공 정오기준 가시성 확보 모듈의 경우 2,300 ~ 3,500lx를 나타내고 있어 대비 현상이나 창측의 급격한 조도 변화가 적은 시환경 구축이 가능 ${\bullet}$ 12시경 휘도는 창측면, 실내 벽체, 코너 바닥면을 대상으로 a-si BIPV 모듈을 적용한 경우 휘도비가 12:1로 KS나 IESNA의 광원과 근접면의 비 20:1 범위에 모두 존재, 적합한 것으로 분석되었으나 c-si의 경우는 그림자로 인한 대비 현상이 발생, 작업 시환경 문제 발생. ${\bullet}$ 이중시스템 창호와 비교하여 단열 성능 떨어짐. 발전시간대 창유리 면 온도 상승 으로 하절기 냉방부하 증가. ${\bullet}$ 자외선은 100% 가까이 차단, 적외선은 13~42%만 투과되고 가시광선은 13% 투과율을 나타내어 일반 창에 칼라 코팅을 적용하는 것과 유사한 경향을 나타냄.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.113.1-113.1
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• 2011

PEMS (printed electro-mechanical system) is fabricated by means of various printing technologies. Passive and active compo-nents in 2D or 3D such as conducting lines, resistors, capacitors, inductors and TFT(Thin Film Transistor), which are printed withfunctional materials, can be classified in this category. And the issue of PEMS is applied to a R2R process in the manu-facturing process. In many electro-devices, the vacuum process is used as the manufacturing process. However, the vacuum process has a problem, it is difficult to apply to a continuous process such as a R2R(roll to roll) printing process. In this paper, we propose an ESD (electro static deposition) printing process has been used to apply an organic solar cell of thin film forming. ESD is a method of liquid atomization by electrical forces, an electrostatic atomizer sprays micro-drops from the solution injected into the capillary with electrostatic force generated by electric potential of about several tens kV. ESD method is usable in the thin film coating process of organic materials and continuous process as a R2R manufacturing process. Therefore, we experiment the thin films forming of PEDOT:PSS layer and active layer which consist of the P3HT:PCBM. The organic solar cell based on a P3HT/PCBM active layer and a PEDOT:PSS electron blocking layer prepared from ESD method shows solar-to-electrical conversion efficiency of 1.42% at AM 1.5G 1sun light illumination, while 1.86% efficiency is observed when the ESD deposition of P3HT/PCBM is performed on a spin-coated PEDOT:PSS layer.