• 한국공작기계학회논문집
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• 제16권6호
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• pp.231-236
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• 2007

In this paper, we studied the possibility of non-contact bill counting method using optical fiber sensor instead of traditionally used friction counting method. To implement non-contact counting, we designed and made optical fiber sensor and related parts. optical fiber sensor is made of optical fiber of 1mm diameter, photo diode and laser diode. Based on the conclusion which derived from preliminary experiment, instrument part is designed to make unevenness on the surface of bill paper and to stay parallel with optical fiber section. By analyzing the signal of optical sensor, we made counting program. Experimental instrument is composed of sensor part, instrument part, signal handling part. We checked the possibility of non-contact counting method after implementing experiment by using optical fiber sensor and instrument part.

• 한국정밀공학회지
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• 제14권11호
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• pp.110-117
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• 1997

This paper discusses numerically and experimenally several design parameters for the plate- type capacitive displacement sensor. The influenences of shape of this sensor on the sensitivity are numerically analyzed with the charge density method. Using many test sensor plates of different shape for verifing the validity of this method can not guarantee the repetibility of experiments. Therefore we made specially the test sensor plate so that experiments of effects of shape of this sensor on sensitivity can be done with only that plate. Results from these experiments agree well with those from numerical analysis.

• Smart Structures and Systems
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• 제2권2호
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• pp.189-208
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• 2006

Monitoring large-scale civil engineering structures such as offshore platforms and high-large buildings requires a large number of sensors of different types. Innovative sensor data information technologies are very extremely important for data transmission, storage and retrieval of large volume sensor data generated from large sensor networks. How to obtain the optimal sensor set and placement is more and more concerned by researchers in vibration-based SHM. In this paper, a method of determining the sensor location which aims to extract the dynamic parameter effectively is presented. The method selects the number and place of sensor being installed on or in structure by through the tolerance domain statistical inference algorithm combined with second order sensitivity technology. The method proposal first finds and determines the sub-set sensors from the theoretic measure point derived from analytical model by the statistical tolerance domain procedure under the principle of modal effective independence. The second step is to judge whether the sorted out measured point set has sensitive to the dynamic change of structure by utilizing second order characteristic value sensitivity analysis. A 76-high-building benchmark mode and an offshore platform structure sensor optimal selection are demonstrated and result shows that the method is available and feasible.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.103-109
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• 2001

Soft sensor is an effective method to deal with the estimation of variables, which are difficult to measure because of the reasons of economy or technology. Fuzzy logic system can be used to develop the soft sensor model by infinite rules, but the fuzzy dividing of variable sets is a key problem to achieve an accurate fuzzy logic model, In this paper, we proposed a new method to develop soft sensor model based on fuzzy neural network. First, using a novel method to divide the variable fuzzy sets by the process input and output data. Second, developing the fuzzy logic model based on that fuzzy set dividing. After that, expressing the fuzzy system with a fuzzy neural network and getting the initial soft sensor model based FNN. Last, adjusting the relative parameters of soft sensor model by the BP learning method. The effectiveness of the method proposed and the preferable generalization ability of soft sensor model built are demonstrated by the simulation.

• 한국통신학회논문지
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• 제35권9B호
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• pp.1322-1329
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• 2010

As body sensor network (BSN) research becomes mature, the need for managing power consumption of sensor nodes has become evident since most of the applications are designed for continuous monitoring. Real time Electrocardiograph (ECG) analysis on sensor nodes is proposed as an optimal choice for saving power consumption by reducing data transmission overhead. Smart sensor nodes with the ability to categorize lately detected ECG cycles communicate with base station only when ECG cycles are classified as abnormal. In this paper, ECG classification algorithms are described, which categorize detected ECG cycles as normal or abnormal, or even more specific cardiac diseases. Our Euclidean distance (ED) based classification method is validated to be most power efficient and very accurate in determining normal or abnormal ECG cycles. A close comparison of power efficiency and classification accuracy between our ED classification algorithm and generalized linear model (GLM) based classification algorithm is provided. Through experiments we show that, CPU cycle power consumption of ED based classification algorithm can be reduced by 31.21% and overall power consumption can be reduced by 13.63% at most when compared with GLM based method. The accuracy of detecting NSR, APC, PVC, SVT, VT, and VF using GLM based method range from 55% to 99% meanwhile, we show that the accuracy of detecting normal and abnormal ECG cycles using our ED based method is higher than 86%.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.434-439
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• 1993

This paper present a sensor based obstacle avoidance method which is based on a VFH(Vector Field Histogram) method. The basic idea of obstacle avoidance is to find a minimum obstacle direction and distance. From the minimum sonar index and the target direction high level system determine steering angle of mobile robot. The sonar sensor system consists of 12 ultra sonic sensor, and each sensor have its direction and safety value. This method has advantage on calculation speed and small memory. This method is implemented on indoor autonomous vehicle'ALiVE-2'.

• 센서학회지
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• 제33권2호
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• pp.63-69
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• 2024

A novel method for measuring hydrogen concentration is introduced, along with its working principle and a novel detection algorithm. This configuration requires no additional reference compartment for potentiometric electrochemical measurements; therefore, it is the most suitable for measuring dissolved hydrogen in the liquid phase. The sensor's electromotive force saturates at a certain point, depending on the hydrogen concentration during the heating process of the sensor operation. This dynamic temperature scanning method provides higher sensitivity than the constant temperature measurement method.

• International Journal of Control, Automation, and Systems
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• 제1권3호
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• pp.395-400
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• 2003

A quantitative performance evaluation of a robot teaching method using a force/moment direction sensor is presented. The performance of the teaching method using the force/moment direction sensor is compared with the conventional teaching pendant method. Two types of teaching tasks were designed and the teaching times required to complete the teaching tasks were measured and compared. Task A requires a teaching motion that involves four degrees of freedom motion. Task B requires a teaching motion that involves six degrees of freedom motion. It was found that, by using the force/moment direction sensor method, the teaching times were reduced by 25% for Task A and 45% for Task B compared to the teaching pendant method.

• 제어로봇시스템학회논문지
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• 제16권5호
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• pp.420-427
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• 2010

This paper describes a localization method based on Monte Carlo Localization approach for a mobile robot. The method uses range data which are measured from ultrasound transmitting beacons whose locations are given a priori. The ultrasound receiver on-board a robot detects the range from the beacons. The method requires several beacons, theoretically over three. The method proposes a sensor model for the range sensing based on statistical analysis of the sensor output. The experiment uses commercialized beacons and detector which are used for trilateration localization. The performance of the proposed method is verified through real implementation. Especially, it is shown that the performance of the localization degrades as the sensor update rate decreases compared with the MCL algorithm update rate. Though the method requires exact location of the beacons, it doesn't require geometrical map information of the environment. Also, it is applicable to estimation of the location of both the beacons and robot simultaneously.

• 한국전자통신학회논문지
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• 제9권8호
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• pp.889-897
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• 2014

무선 통신과 센서 기술의 발달과 더불어 센서 네트워크의 응용이 다양한 분야에서 활용되고 있다. 센서 네트워크 환경에서 센서의 전력 소비를 최소화하는 것은 시스템의 수명을 연장하기 위한 중요한 요인 중의 하나이다. 센서 네트워크에서 각 센서 노드의 전력 소모는 헤드(싱크) 노드와의 통신 방법에 따라 달라 질 수 있다. 본 연구에서는 각 센서의 전력 소모를 최소하기 위한 새로운 계층적 통신 방법을 제안한다. 제안된 방법은 분할 정복 기법을 사용하여 센서 네트워크의 영역을 네 개의 영역으로 구분하고 각 영역에서 헤드 노드와 가장 가까운 노드를 그 노드의 자식 노드로 구성한다. 다음에 더 이상 영역이 분할되지 않을 때까지 같은 방법을 반복적으로 적용하여 계층적 트리를 구성한다. 각 센서 노드는 이러한 계층적 트리를 이용하여 헤드 노드와 통신을 수행한다. 본 연구에서 제안된 결과는 시뮬레이션을 통하여 기존의 방법과 비교하였으며 그 결과 센서 네트워크의 에너지 효율에서 우수한 결과가 도출됨을 보였다.