• PNF and Movement
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• 제21권2호
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• pp.171-183
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• 2023

Purpose: The purpose of this study was to compare universal goniometry (UG), which is commonly used in clinical practice to measure the range of motion (ROM) of finger joints with a wearable soft sensor glove, and to analyze the reliability to determine its usefulness. Methods: Ten healthy adults (6 males, 4 females) participated in this study. The metacarpophalangeal joint (MCP), interphalangeal joint (IP), and proximal interphalangeal joint (PIP) of both hands were measured using UG and Mollisen HAND soft sensor gloves during active flexion, according to the American Society for Hand Therapists' measurement criteria. Measurements were taken in triplicate and averaged. The mean and standard deviation of the two methods were calculated, and the 95% limits of agreement (LOA) of the measurements were calculated using the intraclass correlation coefficient (ICC) and Bland-Altman plot to examine the reliability and discrepancies between the measurements. Results: The results of the mean values of the flexion angles for the active range of motion (AROM) of the finger joints showed large angular differences in the finger joints, except for the MCP of the thumb. In the inter-rater reliability analysis according to the measurement method, the ICC (2, 1) value showed a low level close to 0, and the mean difference by the Bland-Altman plot showed a value greater than 0, showing a pattern of discrepancy. The 95% LOA had a wide range of differences. Conclusion: This study is a preliminary study investigating the usefulness of the soft sensor glove, and the reliability analysis showed a low level of reliability and inconsistency. However, if future studies can overcome the limitations of this study and the technical problems of the soft sensor glove in the development stage, it is suggested that the measurement instrument can show more accurate measurement and higher reliability when measuring ROM with UG.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.176.2-176.2
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• 2014

In this work, we demonstrated that the fabrication of flexible graphene-based chemical sensor with heaters by soft lithographic patterning method [1]. First, monolayer and multilayer graphene were prepared by thermal chemical vapor deposition transferred onto SiO2 / Si substrate in order to fabrication of patterned-sensor and -heater. Second, patterned-monolayer and multilayer graphene were detached through soft lithography process, which was transferred on top and bottom sides of PET film. Third, Au / Ti (Thickness : 100/30 nm) electrodes were deposited end of the patterned-graphene line by sputtering system. Finally, we measured sensor properties through injection of NO2 and CO2 gas on different temperature with voltage change of graphene heater.

• Journal of Semiconductor Engineering
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• 제1권3호
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• pp.81-87
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• 2020

An instrumentation amplifier (IA) and an analog-to-digital converter (ADC) are essential circuit blocks for accurate and robust sensor readout systems. This paper introduces recent advances in radiation-hardening by design (RHBD) techniques applied for the sensor readout integrated circuits (IC), e.g., the three-op-amp IA and the successive-approximation register (SAR) ADC, operating against total ionizing dose (TID) and singe event effect (SEE) in harsh radiation environments. The radiation-hardened IA utilized TID monitoring and adaptive reference control to compensate for transistor parameter variations due to radiation effects. The radiation-hardened SAR ADC adopts delay-based double-feedback flip-flops to prevent soft errors which flips the data bits. Radiation-hardened IA and ADC were verified through compact model simulation, and fabricated CMOS chips were measured in radiation facilities to confirm their radiation tolerance.

• 전자공학회논문지 IE
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• 제43권3호
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• pp.34-40
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• 2006

일반적으로 유체나 연료 공급 장치는 모터를 제어하기 위한 특별한 센서가 필요하고, 센서를 부착하기 위한 보조 장치와 부착하기 위한 공간이 필요하다. 또한 신호선 및 기타 배선 등이 필요하여 어려운 점이 따르게 된다. 본 논문에서는, 불편함과 문제점을 해결하기 위하여 홀센서를 이용한 제어시스템을 제안하였고, 시스템의 제어원리는 모터 동작 단계에 따라 전류흐름에 차이가 발생한다는 것을 이용하였다. 또한 제어 시스템이 우수할 뿐만 아니라 센서 설치에 따른 고장을 줄일 수 있었고, 재료비 및 인건비를 절감할 수 있다. Auto-Pumping 시스템은 Soft-Ware적응용을 통해 모든 유체 공급 시스템에 적용할 수 있으며, 차후에 시스템을 이용한 여러 종류의 장치를 개발할 수 있으리라 본다.

• 센서학회지
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• 제12권2호
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• pp.79-87
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• 2003

본 논문에서는 비선형 특성을 갖는 센서 배열을 사용하는 시스템에서, 센서 배열에 soft computing을 이용하여 선형적인 특성을 얻고, 배열의 특성을 이용하여 외란의 영향을 감소시켜 시스템의 성능을 향상시키는 방법을 제안한다. 대표적인 예로 배열에 사용된 광전도 센서인 CdS는 단일 CdS 셀 조차도 비선형적인 특성을 갖고 있기 때문에 비선형 특성을 소속 함수로 표현하는 퍼지 변수를 사용한다. 배열로 사용되는 센서에 각 단일 센서의 소속 함수와 특성을 이용하는 퍼지 논리를 적용하여 전체적으로 선형화된 센서 특성을 얻는다. 각 센서의 비선형적 요소를 표현하는 소속함수의 파라미터들에 유전 알고리즘을 사용하여 최적화 된 선형 특성을 얻어 시스템의 성능을 향상시킬 수 있다. 또한 보정을 위한 센서를 추가하지 않고 센서 배열의 특성을 이용하여 광전도 센서가 민감한 영향을 받는 외란을 보정하여 시스템의 외란 제거 성능을 향상시킬 수 있다. CdS 센서 배열의 자체 비선형성 뿐만 아니라 입력되는 물체의 그림자는 경계가 뚜렷하지 않고 흐릿하므로 퍼지 논리를 이용하는 방법이 거리측정과 외부 광원에 의한 외란에 대해 향상된 결과를 보인다. 제안된 방법을 적용한 센서 배열을 자기부상(Magnetic Levitation System)에서 볼의 거리 측정에 적용하여 성능을 검증한다.

• 센서학회지
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• 제25권3호
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• pp.178-183
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• 2016

Semiconductor gas sensors based on metal oxide are widely used in a number of applications, from health and safety to energy efficiency and emission control. Nanomaterials including nanowires, nanorods, and nanoparticles have dominated the research focus in this field owing to their large number of surface sites that facilitate surface reactions. Recently, metal oxide hollow structures using soft templates have been developed owing to their high sensing properties with large-area uniformity. Here, we provide a brief overview of metal oxide hollow structures and their gas-sensing properties from the aspects of template size, morphology, and additives. In addition, a gas-sensing mechanism and perspectives are presented.

• Korean Chemical Engineering Research
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• 제48권4호
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• pp.475-482
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• 2010

화상분석(image analysis)을 이용하여 제품의 외관(外觀) 품질을 정량적으로 추정할 수 있는 소프트 센서를 설계하고, 이를 제품의 품질 모니터링에 적용하는 연구를 수행하였다. 여기에 사용된 방법론은 크게 다음의 세 단계로 구성되어 있다: (1) 웨이블릿 변환(wavelet transform)을 이용한 화상으로부터의 질감(texture) 특징 추출, (2) 추출된 질감특징의 부공간 투영(projection on subspace)을 통한 제품 외관의 추정, 그리고 (3) 질감특징의 잠재변수(latent variables) 즉, 외관의 수치적 추정치를 목적에 맞게 사용. 이 방법에서는 제품의 외관을 서로 다른 불연속적인 부류로의 분류 보다는, 연속적인 외관 변화를 일관적이고 정량적으로 추정하는데 초점을 두고자 한다. 이 방법은 인조대리석 외관의 수치적 추정과 품질 모니터링 적용사례를 통해 설명되었다.

• 센서학회지
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• 제29권4호
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• pp.237-242
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• 2020

This paper deals with relative position estimation using a Kalman filter (KF) based on inertial sensors that have been widely used in various biomechanics-related outdoor applications. In previous studies, the relative position is determined using relative orientation and predetermined segment-to-joint (S2J) vectors, which are assumed to be constant. However, because body segments are influenced by soft tissue artifacts (STAs), including the deformation and sliding of the skin over the underlying bone structures, they are not constant, resulting in significant errors during relative position estimation. In this study, relative position estimation was performed using a KF, where the S2J vectors were adopted as time-varying states. The joint constraint and the variations of the S2J vectors were used to develop a measurement model of the proposed KF. Accordingly, the covariance matrix corresponding to the variations of the S2J vectors continuously changed within the ranges of the STA-causing flexion angles. The experimental results of the knee flexion tests showed that the proposed KF decreased the estimation errors in the longitudinal and lateral directions by 8.86 and 17.89 mm, respectively, compared with a conventional approach based on the application of constant S2J vectors.

• 로봇학회논문지
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• 제11권3호
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• pp.133-139
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• 2016

Increasing interest of human health, building bio-database (Bio DB) has been become a hot issue in life science. Consequently, Single Cell Analysis (SCA) which can explain biodiversity of lives has been a significant factor for building Bio DB. In numerous studies from these analyses, they have been showed that mechanical properties of cells can serve explanation of biological heterogeneity and criterion of disease states. Therefore, measuring mechanical properties of cells have great potential to be used in bio-medical applications. However, traditionally, many researchers have undergone difficult and time consuming work because handling small sized cells usually requires high-skilled technique. Thus, this paper shows robotized stiffness measurement technique using fixed ended beam sensor, precision motorized stage and substrate which have wall structure.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.51-54
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• 2000

We are concerned with processing methods of the measurement values of sensors in the control system. When some faults happen to sensor components, the measurement value of sensors cause the malfunction of the plant. So it is necessary to detect and reduce the influence of faults to control with reliability for the overall system. The sensor status must be always good for best demonstration of the controller performance. A self-validating sensor detects the sensor state from the measurement value, reconstruct a soft sensor and can improve reliability of the sensor. If sensor faults, the sensor is detected and reconstructed with the best estimate from its correlation to other sensors and historical data. It is applied to the control of a flexible link system with the sensor fault problems in the light sensor module for position to show the applicability. In this paper, we propose a digital controller which reduces deflection of the moving set-point by reconstructing output of a sensor when the sensor fault is detected.