• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.1679-1684
• /
• 2004

This paper introduces a novel approach that can provide the three dimensional information on the movement of a spreader by using two CCD cameras and a laser distance sensor, which enables an ALS (Automatic Landing System) to be used for yard cranes at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as corner detectors for the geometrical matching between the spreader and a container, which provides only 2D information which is not enough for an accurate and fast ALS system required presently. In addition to this deficiency in performance, the price for the system is too high to be adopted widely for the ALS. Therefore, to overcome these defects, a novel method to acquire the three dimensional information for the movement of a spreader including skew and sway angles is proposed using two CCD cameras and a laser distance sensor. To show the efficiency of proposed algorithm, real experiments are performed to show the accuracy improvement in distance measurement by fusing the sensory information of CCD camera and laser distance sensor.

• 한국공작기계학회논문집
• /
• 제14권3호
• /
• pp.67-73
• /
• 2005

An accuracy of theodolite system may be affected by a measurement environment and a measurement distance change from theodolite to scale bar and/or targets. This study was performed for measuring an accuracy when the distance from thodolite system to scale bar was changed $2\~6m$ on the distance 4m between two theodolites. The results showed that an accuracy was ${\pm}0.025mm$ or better when the distance from theodolite system to targets was 3, 4 and 5m. According to the results, it was found that the best distance from theodolite system to scale bar was $3\~4m$ when the collimation distance was $3\~4m$.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.266-268
• /
• 2004

In this study, on-line measuring system were developed to verify performances and functions of traction system that are used in KTX(Korea Train eXpress) synthetically and efficiently, and have been measuring electric signals of vehicle as well as mechanical signals up to the present. Running-braking measuring equipment was constructed in vehicle to optimize signal acquisition and analysis ability of the measuring system. Measurement data of signal were performed acquisition, analysis and evaluation using this equipment. KRRI(Korea Railroad Research Institute) described about main specifications of measuring equipment. Also, the structure and principles as well as main circuit system were explained in brief. KRRI analyzed the characteristics comparing design values with experimental values about running distance, running time and positive acceleration for KTX is running in full traction. We analyzed the distance and time according to number of motor block. In result, running characteristics of traction system in KTX were verified and could be evaluated.

• 센서학회지
• /
• 제22권6호
• /
• pp.387-392
• /
• 2013

Camera rigs for shooting 3D video are classified as manual, motorized, or fully automatic. Even in an automatic camera rig, the process of Stereoscopic 3D (S3D) video capture is very complex and time-consuming. One of the key time-consuming operations is capturing the distance parameters, which are near distance, far distance, and convergence distance. Traditionally these distances are measured by tape measure or triangular indirect measurement methods. These two methods consume a long time for every scene in shot. In our study, a compact laser distance sensing system with long range distance sensitivity is developed. The system is small enough to be installed on top of a camera and the measuring accuracy is within 2% even at a range of 50 m. The shooting time of an automatic camera rig equipped with the laser distance sensing system can be reduced significantly to less than a minute.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.132.1-132
• /
• 2001

In this paper, we have studied for development of unmanned remote supervisory system using mobile communication network, not wire network, not to be affected by space or distance. The unmanned remote supervisory system consists of data processing unit main part and measuring systems (modules part)-temperature measuring module, humidity measuring module and human body sensing module. The data processing unit to collect and process informations of each measuring module has the functions of data communication between a mobile cellular telephone and measuring systems. Each measuring module has supervisory and warning functions for a target of supervision. And then we have designed each system and evaluated accuracy and reliability of the combined total system.

• 한국임상수의학회지
• /
• 제13권2호
• /
• pp.140-143
• /
• 1996

In this paper the development of an automatic body temperature measuring system which can be attached to the milking machine has been studied. Since the disease is highly related to the body temperature of the cattle, early detection of the abnormal temperature would prevent the severe problems which may occur in dairy farms. The electronic component AD590 is used as a temperature sensor for the system. The device is highly robust against the noise since the output signal is the current. So it can be applied to the long distance sensing. The resolution of the signal is $0.1{\circ}C$ and the current is 10 mV. Also the A/D converter is designed for interfacing the sensor with a computer. A temperature measuring experiment using the developed system has been done for measuring the temperature of human beings and the system was proven to be useful for measuring the body temperature of the dairy cattle properly.

• 한국정밀공학회지
• /
• 제17권8호
• /
• pp.60-70
• /
• 2000

In this paper a 3D position measuring device that finds the 3D position of an arbitarily placed object using a camersa system is introduced. The camera system consists of three stepping motors and a CCD camera and a laser. The viewing direction of the camera is controlled by two stepping motors (pan and tilt motors) and the direction of a laser is also controlled by a stepping motors(laser motor). If an object in a remote place is selected from a live video image the x,y,z coordinates of the object with respect to the reference coordinate system can be obtained by calculating the distance from the camera to the object using a structured light scheme and by obtaining the orientation of the camera that is controlled by two stepping motors. The angles o f stepping motors are controlled by a SGI O2 workstation through a parallel port. The mathematical model of the camera and the distance measuring system are calibrated to calculate an accurate position of the object. This 3D position measuring device can be used to acquire information that is necessary to monitor a remote place.

• 한국공작기계학회논문집
• /
• 제14권2호
• /
• pp.48-54
• /
• 2005

The theodolite system consists of two theodolites, a scale bar and a target bu. A measurement accuracy of theodolite system is affected by a measurement distance of each equipment. This study was performed fir measuring an accuracy when the distance from theodolite to scale bar was changed 2~ 6 m on two theodolites distance 3 a The results showed thai the measurement accuracy could be $\pm$0.021 mm when the distance from theodolite to target was 2,3 and 6 n Specially, it was found that the maximum measurement accuracy was 10.017mm on theodolite collimation distance 3m and the distance 4 m of the theodolite and scale bar.

• 환경영향평가
• /
• 제21권3호
• /
• pp.391-407
• /
• 2012

The loss of connectivity and fragmentation of forest landscapes are seriously hindering dispersal of many forest-dwelling species, which may be critical for their viability and conservation by decreasing habitat area and increasing distance among habitats. For understanding their environmental impacts, numerous spatial models exist to measure landscape connectivity. However, general relationships between functional connectivity and landscape structure are lacking, there is a need to develop landscape metrics that more accurately measure landscape connectivity in whole landscape and individual patches. We reviewed functional and structural definition of landscape connectivity, explained their mathematical connotations, and applied representative 13 indices in 3 districts of Seoul having fragmented forest patches with tits, the threshold distance was applied 500m by considering the dispersal of tits. Results of correlation and principal component analysis showed that connectivity indices could be divided by measurement methods whether they contain the area attribute with distance or not. Betweenness centrality(BC), a representative index measuring distance and distribution among patches, appreciated highly stepping stone forest patches, and difference of probability of connectivity(dPC), an index measuring including area information, estimated integrated connectivity of patches. Therefore, for evaluating landscape connectivity, it is need to consider not only general information of a region and species' characteristics but also various measuring methods of landscape connectivity.

• 한국안전학회지
• /
• 제27권4호
• /
• pp.33-37
• /
• 2012

This paper describes the characteristics for ground impedance of counterpoise according to position of auxiliary probe and frequency using the fall-of-potential method and the testing techniques to minimize the measuring errors are proposed. The fall-of-potential method is theoretically based on the potential and current measuring principle and the measuring error is primarily caused by the position of auxiliary probes. In order to analyze the effects of ground impedance due to the distance of the current probe and frequency, ground impedances were measured in case that the distance of current probe was located from 10[m] to 100[m] and the measuring frequency was ranged in 55 [Hz], 128[Hz], 342[Hz], and 513[Hz]. The results could be help to determine the position of auxiliary probe when the ground impedance was measured at grounding system.