• Title/Summary/Keyword: Distance Sensing

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FORMOSAT-2'S EFFECTIVENESS TO TAIWAN'S PUBLIC EDUCATION

  • Chern, Jeng-Shing;Wu, Lance;Liou, Yuei-An
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.959-962
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    • 2006
  • Public education is undoubtedly a very important aspect for a country to develop space program. People have the rights to understand how the tax they paid is being used. This paper addresses the effectiveness of FORMOSAT-2 on public education in Taiwan. As the first remote sensing satellite of the National Space Organization (NSPO) of Taiwan, FORMOSAT-2 is a small satellite of 746 kg mass for two remote sensing missions: Earth and upward lightning observations. The mission orbit is sun-synchronous of 888 km altitude for exactly 14 revolutions per day. For earth observation, the payload is an advanced high resolution remote sensing instrument (RSI) with ground sampling distance (GSD) 2 m in panchromatic (PAN) band and 8 m in four multi-spectral (MS) bands. For upward lightning observation, the payload is an imager of sprites and upper atmospheric lightning (ISUAL). After more than two years of Earth observation started in June 2004, the effectiveness of FORMOSAT-2 images on public education in Taiwan is very promised. Five domestic universities and one private company in Taiwan have signed contracts respectively with NSPO to take the roles of satellite image investigator and distributor. A private company has signed contract with NSPO to generate and provide URMAP (= your map) in its website for general public applications by using FORMOSAT-2 images. The Newtonkids Book Company used FORMOSAT-2 images to publish a kind of calendar for children education purpose. Besides, a science team in National Cheng Kung University (NCKU) is doing the research work on the 3820 (up to 30 June 2006) transient luminous events (TLEs) observed by FORMOSAT-2.

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Improved Algorithm of Hybrid c-Means Clustering for Supervised Classification of Remote Sensing Images (원격탐사 영상의 감독분류를 위한 개선된 하이브리드 c-Means 군집화 알고리즘)

  • Jeon, Young-Joon;Kim, Jin-Il
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.3
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    • pp.185-191
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    • 2007
  • Remote sensing images are multispectral image data collected from several band divided by wavelength ranges. The classification of remote sensing images is the method of classifying what has similar spectral characteristics together among each pixel composing an image as the important algorithm in this field. This paper presents a pattern classification method of remote sensing images by applying a possibilistic fuzzy c-means (PFCM) algorithm. The PFCM algorithm is a hybridization of a FCM algorithm, which adopts membership degree depending on the distance between data and the center of a certain cluster, combined with a PCM algorithm, which considers class typicality of the pattern sets. In this proposed method, we select the training data for each class and perform supervised classification using the PFCM algorithm with spectral signatures of the training data. The application of the PFCM algorithm is tested and verified by using Landsat TM and IKONOS remote sensing satellite images. As a result, the overall accuracy showed a better results than the FCM, PCM algorithm or conventional maximum likelihood classification(MLC) algorithm.

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Sensing Technologies for Grain Crop Yield Monitoring Systems: A Review

  • Chung, Sun-Ok;Choi, Moon-Chan;Lee, Kyu-Ho;Kim, Yong-Joo;Hong, Soon-Jung;Li, Minzan
    • Journal of Biosystems Engineering
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    • v.41 no.4
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    • pp.408-417
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    • 2016
  • Purpose: Yield monitoring systems are an essential component of precision agriculture. They indicate the spatial variability of crop yield in fields, and have become an important factor in modern harvesters. The objective of this paper was to review research trends related to yield monitoring sensors for grain crops. Methods: The literature was reviewed for research on the major sensing components of grain yield monitoring systems. These major components included grain flow sensors, moisture content sensors, and cutting width sensors. Sensors were classified by sensing principle and type, and their performance was also reviewed. Results: The main targeted harvesting grain crops were rice, wheat, corn, barley, and grain sorghum. Grain flow sensors were classified into mass flow and volume flow methods. Mass flow sensors were mounted primarily at the clean grain elevator head or under the grain tank, and volume flow sensors were mounted at the head or in the middle of the elevator. Mass flow methods used weighing, force impact, and radiometric approaches, some of which resulted in measurement error levels lower than 5% ($R^2=0.99$). Volume flow methods included paddle wheel type and optical type, and in the best cases produced error levels lower than 3%. Grain moisture content sensing was in many cases achieved using capacitive modules. In some cases, errors were lower than 1%. Cutting width was measured by ultrasonic distance sensors mounted at both sides of the header dividers, and the errors were in some cases lower than 5%. Conclusions: The design and fabrication of an integrated yield monitoring system for a target crop would be affected by the selection of a sensing approach, as well as the layout and mounting of the sensors. For accurate estimation of yield, signal processing and correction measures should be also implemented.

Development of Standing and Moving Human Body Sensing Module Using a Chopper of Shutter Method (셔터방식의 쵸퍼를 이용한 정지 및 이동인체 감지 모듈 개발)

  • Cha, Hyeong-Woo;Lee, Won-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.2
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    • pp.109-116
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    • 2016
  • Sensing module of standing and moving human body using shutter method was developed. The module consists of Fresnel lens, pyroelectric infrared (PIR) sensor, interface circuit of the PIR, micro control unit(MCU), and alarm light emitting diode(LED). The principle for standing human body is chopping the thermal of human body using camera shutter. The human sensing signal in MCU by algorithm of interrupt function is detected. By unifying an apparatus and print circuit board(PCB), the developed module can be replaced as commercial moving human body detector. Experiment results show that sensing distance is about 7.0m and sensing angles is about $110^{\circ}$ at room temperature. In these condition, sending ratio was 100% and the power dissipation of the module was 100mW.

Development of Long-perimeter Intrusion Detection System Aided by deep Learning-based Distributed Fiber-optic Acoustic·vibration Sensing Technology (딥러닝 기반 광섬유 분포 음향·진동 계측기술을 활용한 장거리 외곽 침입감지 시스템 개발)

  • Kim, Huioon;Lee, Joo-young;Jung, Hyoyoung;Kim, Young Ho;Kwon, Jun Hyuk;Ki, Song Do;Kim, Myoung Jin
    • Journal of Sensor Science and Technology
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    • v.31 no.1
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    • pp.24-30
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    • 2022
  • Distributed fiber-optic acoustic·vibration sensing technology is becoming increasingly popular in many industrial and academic areas such as in securing large edifices, exploring underground seismic activity, monitoring oil well/reservoir, etc. Long-range perimeter intrusion detection exemplifies an application that not only detects intrusion, but also pinpoints where it happens and recognizes kinds of threats made along the perimeter where a single fiber cable was installed. In this study, we developed a distributed fiber-optic sensing device that measures a distributed acoustic·vibration signature (pattern) for intrusion detection. In addition, we demontrate the proposed deep learning algorithm and how it classifies various intrusion events. We evaluated the sensing device and deep learning algorithm in a practical testbed setup. The evaluation results confirm that the developed system is a promising intrusion detection system for long-distance and seamless recognition requirements.

Design of ToF-Stereo Fusion Sensor System for 3D Spatial Scanning (3차원 공간 스캔을 위한 ToF-Stereo 융합 센서 시스템 설계)

  • Yun Ju Lee;Sun Kook Yoo
    • Smart Media Journal
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    • v.12 no.9
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    • pp.134-141
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    • 2023
  • In this paper, we propose a ToF-Stereo fusion sensor system for 3D space scanning that increases the recognition rate of 3D objects, guarantees object detection quality, and is robust to the environment. The ToF-Stereo sensor fusion system uses a method of fusing the sensing values of the ToF sensor and the Stereo RGB sensor, and even if one sensor does not operate, the other sensor can be used to continuously detect an object. Since the quality of the ToF sensor and the Stereo RGB sensor varies depending on the sensing distance, sensing resolution, light reflectivity, and illuminance, a module that can adjust the function of the sensor based on reliability estimation is placed. The ToF-Stereo sensor fusion system combines the sensing values of the ToF sensor and the Stereo RGB sensor, estimates the reliability, and adjusts the function of the sensor according to the reliability to fuse the two sensing values, thereby improving the quality of the 3D space scan.

Primary user localization using Bayesian compressive sensing and path-loss exponent estimation for cognitive radio networks

  • Anh, Hoang;Koo, Insoo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.10
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    • pp.2338-2356
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    • 2013
  • In cognitive radio networks, acquiring the position information of the primary user is critical to the communication of the secondary user. Localization of primary users can help improve the efficiency with which the spectrum is reused, because the information can be used to avoid harmful interference to the network while simultaneity is exploited to improve the spectrum utilization. Despite its inherent inaccuracy, received signal strength based on range has been used as the standard tool for distance measurements in the location detection process. Most previous works have employed the path-loss propagation model with a fixed value of the path loss exponent. However, in actual environments, the path loss exponent for each channel is different. Moreover, due to the complexity of the radio channel, when the number of channel increases, a larger number of RSS measurements are needed, and this results in additional energy consumption. In this paper, to overcome this problem, we propose using the Bayesian compressive sensing method with a calibrated path loss exponent to improve the performance of the PU localization method.

Design of an Ontology-based Autonomous Navigation System with Conceptualization of Sensing Information (감지 정보의 개념화에 의한 온톨로지 기반의 자율주행 시스템의 설계)

  • Jeong, Hye-C.;Lee, In-K.;Seo, Suk-T.;Kwon, Soon-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.5
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    • pp.579-585
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    • 2008
  • Recently, many researches on autonomous mobile system have been proposed, which are possible to recognize its surrounding environment and navigate to destination without supervisor's intervention. Various sensors are mounted on the autonomous systems in order for the systems to move to destination safely without any accident. In this paper, we design an ontology-based autonomous system mounted laser distance sensors and cameras, and propose a method to conceptualize sensing information. We show the validity of the proposed method through the experiments of the system's navigation.

AN ASSESSMENT OF LAND COVER CHANGES AND ASSOCIATED URBANIZATION IMPACTS ON AIR QUALITY IN NAWABSHAH, PAKISTAN: A REMOTE SENSING PERSPECTIVE

  • Shaikh, Asif Ahmed;Gotoh, Keinosuke
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.555-558
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    • 2006
  • In recent years, urban development has expanded rapidly in Nawabshah City of Pakistan. A major effect associated with this population trend is transformation of the landscape from natural cover types to increasingly impervious urban land. The core objective of this study are to provide time-series information to define and measure the urban land cover changes of Nawabshah, Pakistan between the years 1992 and 2002, and to examine related urbanization impacts on air quality of the study area. Two multi-temporal Landsat images acquired in 1992 and 2002 together with standard topographical maps to measure land cover changes were used in this study. The image processing and data manipulation were conducted using algorithms supplied with the ERDAS Imagine software. An unsupervised classification approach, which uses a minimum spectral distance to assign pixels to clusters, was used with the overall accuracy ranging from 84 percent to 92 percent. Land cover statistics demonstrate that during the study period (1992-2002) extensive transformation of barren and vegetated lands into urban land have taken place in Nawabshah City. Results revealed that land cover changes due to urbanization has not only contaminated the air quality of the study area but also raised the health concerns for the local residents.

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Document Clustering Scheme for Large-scale Smart Phone Sensing (대규모 스마트폰 센싱을 위한 문서 클러스터링 기법)

  • Min, Hong;Heo, Junyoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.253-258
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    • 2014
  • In smartphone sensing which monitors various social phenomena of the individuals by using embedded sensors, managing metadata is one of the important issue to process large-scale data, improve the data quality, and share collected data. In this paper, we proposed a document clustering scheme for the large-scale metadata management architecture which is designed as a hybrid back-end consisting of a cluster head and member nodes to reduce the server-side overhead. we also verified that the proposed scheme is more efficient than the distance based clustering scheme in terms of the server-side overhead through simulation results.