• Title/Summary/Keyword: real time systems

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Automatic Generation Method of Road Data based on Spatial Information (공간정보에 기반한 도로 데이터 자동생성 방법)

  • Joo, In-Hak;Choi, Kyoung-Ho;Yoo, Jae-Jun;Hwang, Tae-Hyun;Lee, Jong-Hun
    • Journal of Korea Spatial Information System Society
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    • v.4 no.2 s.8
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    • pp.55-64
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    • 2002
  • VEfficient generation of road data is one of the most important issues in GIS (Geographic Information System). In this paper, we propose a hybrid approach for automatic generation of road data by combining mobile mapping and image processing techniques. Mobile mapping systems have a form of vehicle equipped with CCD camera, GPS, and INS. They can calculate absolute position of objects that appear in acquired image by photogrammetry, but it is labor-intensive and time-consuming. Automatic road detection methods have been studied also by image processing technology. However, the methods are likely to fail because of obstacles and exceptive conditions in the real world. To overcome the problems, we suggest a hybrid method for automatic road generation, by exploiting both GPS/INS data acquired by mobile mapping system and image processing algorithms. We design an estimator to estimate 3-D coordinates of road line and corresponding location in an image. The estimation process reduces complicated image processing operations that find road line. The missing coordinates of road line due to failure of estimation are obtained by cubic spline interpolation. The interpolation is done piecewise, separated by rapid change such as road intersection. We present experimental results of the suggested estimation and interpolation methods with image sequences acquired by mobile mapping system, and show that the methods are effective in generation of road data.

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A Micro Solar Energy Harvesting Circuit with MPPT Control (MPPT 제어기능을 갖는 마이크로 빛에너지 하베스팅 회로)

  • Yoon, Eun-Jung;Park, Jong-Tae;Yu, Chong-Gun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.105-113
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    • 2013
  • In this paper a micro solar energy harvesting system with MPPT(Maximum Power Point Tracking) control using a miniature PV(photovoltaic) cell of which the output is less than 0.5V is proposed. The MPPT control is implemented using linear relationship between the open-circuit voltage of a PV cell and its MPP(Maximum Power Point) voltage such that a pilot PV cell can track the MPP of the main PV cell in real time. The proposed circuit is designed in 0.18um CMOS process. The designed chip area is $900um{\times}1370um$ including a load charge pump and pads. Measured results show that the designed system can track the MPP voltage changes with variations of light intensity. The designed circuit with MPPT control delivers MPP voltages to load even though the load is heavy such that it can supply more power when the MPPT control is applied. The proposed circuit does not require any precharged battery resulting in more suitability for miniaturized self-powered systems compared to the existing works.

Dynamic Power Management Framework for Mobile Multi-core System (모바일 멀티코어 시스템을 위한 동적 전력관리 프레임워크)

  • Ahn, Young-Ho;Chung, Ki-Seok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.7
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    • pp.52-60
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    • 2010
  • In this paper, we propose a dynamic power management framework for multi-core systems. We reduced the power consumption of multi-core processors such as Intel Centrino Duo and ARM11 MPCore, which have been used at the consumer electronics and personal computer market. Each processor uses a different technique to save its power usage, but there is no embedded multi-core processor which has a precise power control mechanism such as dynamic voltage scaling technique. The proposed dynamic power management framework is suitable for smart phones which have an operating system to provide multi-processing capability. Basically, our framework follows an intuitive idea that reducing the power consumption of idle cores is the most effective way to save the overall power consumption of a multi-core processor. We could minimize the energy consumption used by idle cores with application-targeted policies that reflect the characteristics of active workloads. We defined some properties of an application to analyze the performance requirement in real time and automated the management process to verify the result quickly. We tested the proposed framework with popular processors such as Intel Centrino Duo and ARM11 MPCore, and were able to find that our framework dynamically reduced the power consumption of multi-core processors and satisfied the performance requirement of each program.

A Study on Apply of Smart Sensors for Wheelchair Balancing Control (휠체어 균형 조정을 위한 스마트 센서의 적용에 관한 연구)

  • Ma, Linh Van;Cho, Young-bin;Kim, Jinsul
    • Journal of Digital Contents Society
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    • v.19 no.8
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    • pp.1585-1592
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    • 2018
  • Due to un-balancing weight allocation on the wheelchair the existing wheelchair system are faced with the risk of flipping or falling when a wheelchair goes up to a hill. In to order to be safer during riding the wheelchair, in this paper, we proposed a real-time new solution using the integrated Gyro Sensor and Tilt Sensor for controlling the balance. Because the typical property of wheelchair is for the special user who meets the difficulty in moving on foot the maintain the balance of wheel-chair systems have become important and helpful. In our method, we calculate the seat angle using information from Tilt Sensor. However, due to the law of inertia when a wheelchair is moving there is a deviation in the output value of Tilt Sensor. Therefore, we have to optimize the value of the angle by utilizing the acceleration that is the output of the Gyro Sensor. We took the advantages by using the combination of Gyro and Tilt sensors. Moreover, we also solved the consumption issue of the whole system. Through various experimentations with usage of ZigBee sensor module, the power consumption for the balancing system is reduced significantly.

GIS Based Real-Time Transit Information Integration and Its Transit Planning Implications

  • Hwang, Da-Hae;Kim, Dong-Young;Choi, Yun-Soo;Cho, Seong-Kil
    • Journal of Korean Society for Geospatial Information Science
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    • v.15 no.2 s.40
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    • pp.87-93
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    • 2007
  • Over the years, Advanced Public Transportation System (APTS) has been implemented to manage and operate public transportation system. With the expanding mass spatio-temporal data such as comprehensive spatial information of each individual passenger and public transportation vehicle, it has been required to consolidate and analyze these multiple data sets from various sources. This paper demonstrates how GIS is utilized for the consolidation of massive transit related spatio-temporal information. And it presents effective applications to improve transit planning process and support transit related decision-making activities. GIS based system is used to combine multi-agents' data in the areas of transit operation and individual transit ride and transfer management. Due to the unique comprehensiveness and the level of detail of the data provide by the Seoul Transit system, this GIS based information consolidation is the first in its class. Based on the integrated database, this paper describes the effective and efficient GIS based analysis deployed in a transportation system planning process. The data integration systems and analytic models developed in this paper can be transferred and applied by any municipal governments provided that the appropriate data is available.

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The Study on Threats of Information Security and Their Solutions in the Fourth Industrial Revolution (4차 산업혁명 시대에 정보보안의 위협요인과 대응방안에 대한 연구)

  • Cho, Sung-Phil
    • Korean Security Journal
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    • no.51
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    • pp.11-35
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    • 2017
  • The third industrial revolution, characterized by factory automation and informatization, are moving toward the fourth industrial revolution which is the era of superintelligence and supernetworking through rapid technology innovation. The most important resources in the fourth industrial revolution are information or data since the most of industrial and economic activities will be affected by information in the fourth industrial revolution. Therefore we can expect that more information will be utilized, shared and transfered through the networks or systems in real time than before so the significance of information management and security will also increase. As the importance of information resource management and security which is the core of the fourth industrial revolution increases, the threats on information security are also growing so security incidents such as data breeches and accidents take place more often. Various and thorough solutions are highly needed to protect information resources from security risks because information accidents or breaches seriously damage brand image and cause huge financial damage to organization. The purpose of this study is to research general trends on data breaches and accident that can be serious threat of information security. Also, we will provide resonable solutions to protect data from nine attack patterns or other risk factors after figuring out each characteristic of nin attack patterns in data breaches and accidents.

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Evaluation Scheme of the GPS Positional Accuracy for Dynamic Bus Route Information using SMB(Single Buffering Method) (단일 버퍼링 기법을 이용한 동적 버스 노선 정보의 GPS 위치 정확도 평가 방안)

  • Park, Hong-Gi;Joo, Yong-Jin
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.6
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    • pp.677-685
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    • 2011
  • In order to enhance public transportation and to maintain information credibility, improvement of accuracy regarding route and positional information of public transport is very significant. There have been a variety of methods using GPS to measure accuracy of location-based services. However, the researches of evaluation regarding kinematic position of linear objects measured by vehicle/kinematic GPS are still insufficient. That's why our paper aims to suggest method of evaluation accuracy on a real-time bus route surveyed by GPS by SBM(Single Buffering Method). To make it come true, we compared the findings on the static and dynamic positioning by using PP(Point Positioning), DGPS and GPS/INS integrated systems and analyzed the accuracy and error effects among them, focusing on Anyang city. Consequently, we can find out that in case of P.P. comparing positioning accuracy between RTK DGPS and GPS/INS, both of them have survey result within a margin of error of 5m. More importantly, we can evaluate positional accuracy of each GPS system based on the work provision of a public survey such as error for P.P.(14.5m, 18.1m), DGPS(16.9m, 18.5m), and GPS/INS(18.4m, 18.5m). We are expecting that proposed method in our paper can be utilized in a wide range of categories such as feasibility testing of GPS field survey and high accuracy of positioning for Bus Information System.

Experimental Performance Evaluation of a Fire System for Apartment Buildings (공동주택 전용화재시스템의 성능평가를 위한 실험적 연구)

  • Jung, Jong-Jin;Hong, A-Reum;Son, Bong-Sei
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.51-56
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    • 2015
  • In Korea, measures to maintain sustainable fire safety performance for apartment buildings are insufficient in terms of fire-fighting products, skilled personnel, and maintenance status. Also, because of the particular features of a fire compartment, it has structural problems that are very likely to cause damage to human life when a fire occurs. Currently, problems with the fire supervisory system installed in an apartment building cannot be checked in real time, so it is difficult to identify the location of a fire accurately. Protected areas are also not assigned to each household, and residents cannot be clearly informed of the occurrence of a fire. As a consequence, safety evacuation cannot be secured. In addition, it is impossible to test the operation performance for water detectors in sprinkler fire extinguishing systems outside of the household. Therefore, an experiment was conducted to evaluate the performance of a remote fire supervisory system. The results show that the system satisfies all performance requirements. Also, an household alarm system was installed in each household to alert of any occurrence of a fire accurately, and the performance of the alarm system was improved to ensure that residents were quickly evacuated.

Implementation of a Real-time Data Display System for a Catchment Scale Automated Weather Observation Network (집수역 규모 무인기상관측망을 위한 실황자료 표출시스템 구축)

  • Jung, Myung Ryong;Kim, Jin-Hee;Moon, Young Eel;Yun, Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.15 no.4
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    • pp.304-311
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    • 2013
  • There have been increasing cases for farmers to install automated weather stations (AWS) at their farms and orchards in order to take countermeasures to more frequent weather disasters caused by climate variability and weather extremes. Although raw data are the same, the additive values as agrometeorological information may vary depending on data processing methods. User demands on appropriate information could also be different among crop species, cropping systems and even cultivars. We designed an internet based AWS data processing and display system to help diverse users (e.g., farmers), extension workers to access their weather data on specific demands. The system was implemented at a rural catchment with 52 $km^2$ land area where 14 automated weather stations are in operation. This note introduces the system and describes the major modules in detail. By linking regional AWS networks, a feasibility for this system as an early warning system is also discussed.

Positioning Accuracy Analysis According to the Change of Blockage Location and GNSS Signal Combination (GNSS 위성신호조합과 장애물 근접에 따른 위치정확도 분석)

  • Lee, Jae One;Yun, Bu Yeol;Park, Chi Young;Choi, Hye Won
    • Journal of Korean Society for Geospatial Information Science
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    • v.22 no.3
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    • pp.39-46
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    • 2014
  • Network RTK positioning, one of GNSS positioning systems, is currently very popular due to its easy operation and low cost. However, the network RTK positioning unquestioningly accepts observation result acquired with an ambiguity fixed-solution regardless of different field conditions and situations, and then it is applied to the practice. This paper, therefore, has investigated the effects of field conditions obtained network RTK survey data for the area with obstacles on the variation of positioning accuracy. Being explained in detail, after conducting survey by GPS-only positioning and combined GPS/GLONASS observations giving changes to the distance from obstacles and elevation angles, and then accuracy results of each positioning method were compared each other. As a result, while GPS-only point positioning method showed more stable results than combined GPS/GLONASS method in the areas with no obstacles, combined method gave better result than GPS-only for the areas with presence of obstacles. Based on the results of this experiment, when the further study is conducted with a variety of different field conditions affecting the survey accuracy, it can be expected that the accuracy of network RTK survey method would become to more popular.