• 대한디지털의료영상학회논문지
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• 제7권1호
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• pp.45-49
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• 2005

목적 : 기존 구내 방사선 촬영에서 사용되었던 Film에서의 노출선량과 Digital Sensor를 이용한 구내 디지털 촬영에서의 노출선량을 비교하여 현재 광범위 하게 사용 되어지고 있는 Digital Sensor가 환자의 피폭선량을 감소하는데 기여하는 정도를 알아본다. 대상 및 방법 : 치아 우식증이 없는 5개의 구치부 치아를 선택하여 석고 블럭에 매식한 후 교합면과 인접면에 우식병소들을 형성하였다. 이를 필름(Kodak Insight; IS, Kodak Co, USA)과 Digital Sensor(Kodak RVG 6000; Kodak Co, USA)에 XCP Instrument(Rinn Co, USA)를 사용하고, 전면에는 조직등가물질인 Acrylic Resin Block 20mm를 설치하였다. Acrylic Resin Block의 관구 측면 에서는 조사선량계를 부착하여 단계별로 변화시키는 노출조건에 대한 조사선량을 측정하였다. 그리고 이렇게 얻어진 영상을 3명의 방사선학 전공의와 1명 의 보존과 전공의가 평가를 하였다. 결과 : Film과 Digital Sensor를 가지고 촬영한 영상을 분석한 결과 노출선량에서도 Digital Sensor는 Film 노출선량과 비슷한 결과를 도출해 낼 수 있었다. 그러나 Digital Sensor로 촬영된 영상의 경우에는 Film 경우보다 좀더 효과적으로 조사선량을 판단 할 수 있었으며, 또한 영상 판독시 필름보다 폭 넓게 응용 할 수 있었다. 결론 : 본 연구에서는 선량 변화에만 의존하는 것이 아니라 Digital Sensor로 촬영시 영상 조절을 병행한다면 좀더 정확하고 효과적인 진단 활동에 도움이 될 수 있을 것으로 사료된다.

• Journal of information and communication convergence engineering
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• 제15권4호
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• pp.232-236
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• 2017

A digital vacuum pressure sensor is designed, fabricated, and characterized using a packaged MEMS analog Pirani gauge. The packaged MEMS analog Pirani gauge requires a current source to heat up a heater in the Pirani gauge. To investigate the feasibility of digitization for the analog Pirani gauge, its implementation is performed with a zero-temperature coefficient current source and microcontroller that are commercially available. The measurement results using the digital vacuum pressure sensor showed that its operating range is 0.05-760 Torr, which is the same as the measurement results of the packaged MEMS analog pressure sensor. The results confirm that it is feasible to integrate the analog Pirani gauge with a commercially available current source and microcontroller. The successful hybrid integration of the analog Pirani gauge and digital circuits is an encouraging result for monolithic integration with a precision current source and ADCs in the state of CMOS dies.

• 한국응급구조학회지
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• 제18권1호
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• pp.107-116
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• 2014

Purpose : The purpose of this study is to demonstrate the effectiveness of using a digital sensor device during CPR by analyzing the results from that chest compressions with a digital sensor device are applied to cardiac arrest patients. Methods : This study analyzed the results from the experiment that 42 people were selected randomly among Korean 119 rescuers, and they divided into the experimental group using a digital sensor device and the control group only using their hands, then they had been observed to conduct chest-compressions to mannequins for 10 minutes. Results : The results were found that compression depth in both the control and experimental group was gradually decreased over time, but the experimental group not only kept the depth but also maintained the speed of chest-compressions close to 100 times a minute. In addition, due to the use of the digital sensor device, the insufficient recoil ratio of chest-compressions was significantly reduced. Conclusion : The results show that conducting chest-compressions with a digital sensor device keeps the compression-death, maintains the speed of chest-compression properly and makes the insufficient relaxation ratio of chest-compressions reduce significantly.

• 로봇학회논문지
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• 제2권3호
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• pp.205-211
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• 2007

In this paper, the prototype of surface EMG (ElectroMyoGram) sensor is developed for the robotic rehabilitation applications, and the developed sensor is composed of the electrodes, analog signal amplifiers, analog filters, ADC (analog to digital converter), and DSP (digital signal processor) for coding the application example. Since the raw EMG signal is very low voltage, it is amplified by about one thousand times. The artifacts of amplified EMG signal are removed by using the band-pass filter. Also, the processed analog EMG signal is converted into the digital form by using ADC embedded in DSP. The developed sensor shows approximately the linear characteristics between the amplitude values of the sensor signals measured from the biceps brachii of human upper arm and the joint angles of human elbow. Finally, to show the performance of the developed EMG sensor, we suggest the application example about the real-time human elbow motion acquisition by using the developed sensor.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.137-140
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• 2002

This paper is proposed a 8-bit anolog to digital converter for CMOS image sensor. A anolog to digital converter for CMOS image sensor is required function to control gain. Proposed anolog to digital converter is used frequency divider to control gain. At 3.3 Volt power supply, total static power dissipation is 8mW and programmable gain control range is 30dB. The gain control range can be easily increased with insertion of additional flip-flop at divided-by-N frequency divider circuit.

• 대한전자공학회논문지
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• 제24권4호
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• pp.590-596
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• 1987

In this paper, it was studied on the design of a sun sensor which is able to sense the declinations of an azimuth angle and a zenith angle for a digital sun seeker control system so that it will seek the sun accurately. And, it was considered the construction of digital controllable algorithms through experiments. Peculiar design method of the sun sensor is that sensor box was constructed with three square silicon solar cells and that the three cells were mounted unsymmetrical forming the

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.566-569
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• 2006

The purpose of this study is to develop digital air meter used pressure sensor for measurement of air content in freshly mixed concrete by pressure method. The digital air meter can enhanced measurement accuracy and uniformity of air content in freshly concretes, according to use of pressure sensor and measuring process automation. Finally, the digital air meter in this study is improved reproducibility and reliability of measurement compared with analog air meter.

• 센서학회지
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• 제26권3호
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• pp.155-159
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• 2017

The analog-to-digital converter (ADC) is an important component in various fields of sensor signal processing. This paper presents an expandable flash analog-to-digital converter (E-flash ADC) for sensor signal processing using a comparator, a subtractor, and a multiplexer (MUX). The E-flash ADC was simulated and designed in $0.35-{\mu}m$ standard complementary metal-oxide semiconductor (CMOS) technology. For operating the E-flash ADC, input voltage is supplied to the inputs of the comparator and subtractor. When the input voltage is lower than the reference voltage, it is outputted through the MUX in its original form. When it is higher than the reference voltage, the reference voltage is subtracted from the input value and the resulting voltage is outputted through the MUX. Operation of the MUX is determined by the output of the comparator. Further, the output of the comparator is a digital code. The E-flash ADC can be expanded easily.

• Nuclear Engineering and Technology
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• 제33권5호
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• pp.514-525
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• 2001

Optimum characteristics of digital X-ray sensor components were analyzed to develop intra- oral dental digital X-ray image sensor using indirect method. Parametric analysis was carried out to optimize the phosphor thickness and the fiber optic plate (FOP) coupling to charge coupled device (CCD). X-ray absorption and light diffusion in the phosphor layer were analyzed by the Monte Carlo method. Real time X-ray image was obtained with prototype X- ray image sensor using general CCD camera with 1∼10 Ip/mm resolution. It has been previously shown that large resolution degradation in X-ray images was caused by miss alignment of FOP to CCD and optical adhesive selection. In this study, we reported that X-ray image quality was greatly improved by using optimized characteristics of alignment device and phosphor thickness.

• 디지털산업정보학회논문지
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• 제5권2호
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• pp.87-93
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• 2009

In this paper, we propose and evaluate the availability of single sensor node using a hierarchial modeling approach. We divides a sensor node into a software and hardware and analyze failures of each component. We construct Markov chains to represent the components of a sensor node, and then we construct a hierarchical model which use fault tree in upper level and Markov chains in lower level. We evaluate the availability and down of single sensor node.