• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.11a
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• pp.167-172
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• 2005

This study based on the experimental data on the daylight responsive dimming systems performance. The purpose of this study increases the energy-saving effects by reducing excessive intensity of radiation of artificial lighting through analyzing incident daylight. The photosensor sends amounts of detected luminous flux to digital control unit(DCU) as a signal and then, it can decide dimming ratios, by received a proper dimming signal from DCU. Generally it is effective to control artificial lighting with the different control ratio of each row by setting a photosensor as same numbers and rows as artificial lighting. However, it is ineffective to do in initial costs of systems aspect in offices. By analyzing the data of this performance and finding regular ration between photosensors. we will execute different dimming ratios to each row of artificial lighting by a single photosensor.

• Journal of Sensor Science and Technology
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• v.3 no.3
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• pp.16-21
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• 1994

A 3-terminal pin-type photosensor with gate contrail is fabricated using standard silicon CMOS IC process. The photosensor of a $100{\mu}m{\times}120{\mu}m$ size has dark current less than 1nA and its breakdown voltage is -14V with a depletion capacitance 0.75 pF at -5V reverse bias. Responsivity at 0V gate voltage is 0.25A/W at $0.633{\mu}m$ wavelength, 0.19A/W at $0.805{\mu}m$. Responsivity increases with increasing gate voltage. The integrated circuit of photosensor and CMOS inverter shows $22K{\Omega}$ transimpedance and photocurrent of $90{\mu}A$ switchs the output state of digital inverter without additional amplifier.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.3
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• pp.231-242
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• 2011

This study examines influences of a daylight dimming control system on the variation of indoor illuminance and lighting energy savings in a small office space. Field measurements and a series of computation were performed for typical types of sky conditions in summer. Results indicate that the daylight illuminance under clear and partly-cloudy sky were close to the target illuminance during a majority of time due to a higher ratio of window to wall. However, the target illuminance was not kept successfully due to the variation of photosensor signals which were strongly influenced by desktop illuminance. The system with partially-shielded conditions succeeded to keep target illuminance under clear sky conditions. The system failed under overcast sky conditions since the electric light output from fixtures caused excessive signals to photosensors due to insufficient daylight on a desktop. Unshielded and fully-shielded conditions were not recommended for effective controls of the systems. The influence of lighting fixtures on photosensors should be minimized to achieve successful lighting controls by daylight dimming systems.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.957-960
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• 2009

Sensor applications of thin-film transistors (TFTs), such as photosensor, magnetic sensor, temperature sensor and chemical sensor, are introduced. Active-matrix circuits and amplifying circuits using poly-Si TFTs are integrated with these sensors to improve sensor performances and generate additional functions. These sensors may be promising applications after flat-panel displays (FPDs) in giant-micro electronics.

• Journal of the Korean Ceramic Society
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• v.56 no.3
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• pp.308-316
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• 2019

CdS_xSe_1-x ternary alloy nanowires (x = 0, 0.5, 1.0) were fabricated by in-situ synthesis on interdigitated electrode. Morphology analysis of the alloy nanowires according to the synthesis zone and composition analysis of the nanowires were carried out by SEM and EDX. The crystal structures of the alloy nanowires were studied by XRD analysis. The I-V characteristics of the nanowire photosensors were analyzed according to the intensity of incident light. The influence of zonal synthesis position on the photosensor response to the wavelength of incident light was also analyzed, and was found to be related to the bandgap of alloy nanowires. The analysis results indicate that photosensors with a specific photoresponse could be selected based on the composition of the source materials of nanowires as well as by controlling the in-situ synthesis zone.

• Journal of the Korean Society of Radiology
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• v.16 no.2
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• pp.157-162
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• 2022

Since preclinical positron emission tomography imaging is performed on small animals that are very small compared to the human body, a detector with excellent spatial resolution is required. For this purpose, a system was constructed using a detector using small scintillation pixels. Since the size of the currently developed and used photosensors is limited, excellent spatial resolution can be obtained when the minimum scintillation pixel and maximum array are used. In this study, the size of the photosensor is fixed and various scintillation pixel arrays are configured to match the size of the scintillation pixels, so that no overlap occurs in the flood image and the maximum scintillation pixel array in which all scintillation pixels are distinguished. For this purpose, DETECT2000, which can simulate a detector module composed of a scintillator and an photosensor, was used. A photosensor consisting of a 4 × 4 array of 3 mm × 3 mm pixels was used, and the scintillation pixel array was configured from 8 × 8 to 13 × 13, and simulations were performed. A flood image was constructed using the data obtained from the photosensor pixel, and the maximum scintillation pixel array that does not overlap the image was found through the flood image and the profile. As a result, the size of the scintillation pixel array in which all scintillation pixels are imaged without overlapping each other in the flood image was 11 × 11.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.3-3
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• 1995

• Journal of the Korean Solar Energy Society
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• v.26 no.3
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• pp.33-43
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• 2006

Daylight dimming control system was analyzed for an indirect lighting system in a small office space with a double skin envelope system. Computer simulations were performed for photosensors with three shielding conditions. The photosensors were placed on the center of ceiling, and backwall. Three sky conditions defined by CIE were considered. Overall, control performance was not very excellent for all conditions. Fully-shielded photosensor achieved good control performance for some cases, but partially-shielded and unshielded photosensors failed to achieve target illuminance. The variation in desktop illuminance due to daylight was examined for a variety of daylight conditions. Linear correlation between desktop illuminance and photosensor illuminance was analyzed using ANOVA.

• Journal of the Korea Society of Computer and Information
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• v.13 no.1
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• pp.219-226
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• 2008

The signal data from human body is very various and much. Because the signals can not occur equally to everyone, so when they analyze their signals, these signals can be used to diagnosis each health sign. In this system, human fingertips are connected with the five vital organs and the six viscera, and if we use these oriental medical diagnosis we can measure the pulse. temperature, and resistant from by reflective photosensor and interpret it's true and false.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.197-201
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• 2003

The purpose of this study is to analyze the slopes of control algorithm and dimming levels based on different inputs and parameters. Different parameters such as photosensor aiming angles, sky types, and seasonal changes were considered. To determine the slopes of control algorithm and dimming levels, photosensor signals and workplan illuminance values were simulated by DayDim program, which is a lighting calculation and analysis tool. A typical small office space was used for simulation and three different sky types in three different seasons were considered. This study shows that differences in dimming levels can occur according to different sky types, if system calibration is conducted in a particular sky type.