• Title/Summary/Keyword: Satellite Internet

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A Study on the Application Technique of 3-D Spatial Information by integration of Aerial photos and Laser data (항공사진과 레이져 데이터의 통합에 의한 3 차원 공간정보 활용기술연구)

  • Yeon, Sang-Ho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.3
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    • pp.385-392
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    • 2010
  • A LiDAR technique has the merits that survey engineers can get a large number of measurements with high precision quickly. Aerial photos and satellite sensor images are used for generating 3D spatial images which are matched with the map coordinates and elevation data from digital topographic files. Also, those images are used for matching with 3D spatial image contents through perspective view condition composed along to the designated roads until arrival the corresponding location. Recently, 3D aviation image could be generated by various digital data. The advanced geographical methods for guidance of the destination road are experimented under the GIS environments. More information and access designated are guided by the multimedia contents on internet or from the public tour information desk using the simulation images. The height data based on LiDAR is transformed into DEM, and the real time unification of the vector via digital image mapping and raster via extract evaluation are transformed to trace the generated model of 3-dimensional downtown building along to the long distance for 3D tract model generation.

A Study on Satellite Broadband Internet Services In High-Speed Vehicle (고속 이동체에서 위성 광대역 인터넷 서비스를 위한 Cross Layer 부호화 방식)

  • Park, Tae-Doo;Kim, Min-Hyuk;Kim, Nam-Soo;Kim, Chul-Sung;Jung, Ji-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.5C
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    • pp.485-497
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    • 2009
  • In this paper, we described DVB-S2 system for mobility. cross layer coding technique are needed to maintain the performance in deep fading channel. Cross layer coding is divided into two kinds of level. First level is Physical layer coding and, second layer is link layer or upper layer coding. Fixed on DVB-S2 short frame coding method as a physical layer, we simulated the various coding method as an upper layer coding. Furthermore, we analyzed the performance of each coding method on according to mobile vehicle speed, data rate, interleaving memory size, and IP packet size.

A DOUBLE-EDGED SWORD: MEDIA AND RELIGION IN THE MIDDLE EAST (WITH SPECIAL EMPHASIS ON IRAN)

  • KHANI, MOHAMMAD HASSAN
    • Acta Via Serica
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    • v.3 no.1
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    • pp.43-56
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    • 2018
  • Religion and new media are two important factors in contemporary Middle Eastern societies. Media is seen as a relatively newcomer while religion has been and remains an old and core component of the fabric of societies in this region. This article is an attempt to examine the encounter of these two phenomena in the Middle East. It will try to explore the variety of ways by which new media have served religion both positively and negatively, and how religion has taken position for and against media in Middle Eastern countries in general and in the Iranian case in particular. It is also the purpose of this article to look at the different aspects of this relationship between media and religion, analyzing how one affected the other, and how this interaction affected society. It is argued that the outcome of the interaction between religion and media has had a great impact on shaping the social and political culture of the countries in this region including Iran. The dimensions of this impact will determine the outcome of the clash between modernity and tradition in the region.

Development of HDF Browser for the Utilization of EOC Imagery

  • Seo, Hee-Kyung;Ahn, Seok-Beom;Park, Eun-Chul;Hahn, Kwang-Soo;Choi, Joon-Soo;Kim, Choen
    • Korean Journal of Remote Sensing
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    • v.18 no.1
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    • pp.61-69
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    • 2002
  • The purpose of Electro-Optical Camera (EOC), the primary payload of KOMPSAT-1, is to collect high resolution visible imagery of the Earth including Korean Peninsula. EOC images will be distributed to the public or many user groups including government, public corporations, academic or research institutes. KARI will offer the online service to the users through internet. Some application, e.g., generation of Digital Elevation Model (DEM), needs a secondary data such as satellite ephemeris data, attitude data to process the EOC imagery. EOC imagery with these ancillary information will be distributed in a file of Hierarchical Data Format (HDF) file formal. HDF is a physical file format that allows storage of many different types of scientific data including images, multidimensional data arrays, record oriented data, and point data. By the lack of public domain softwares supporting HDF file format, many public users may not access EOC data without difficulty. The purpose of this research is to develop a browsing system of EOC data for the general users not only for scientists who are the main users of HDF. The system is PC-based and huts user-friendly interface.

The Utilization of Google Earth Images as Reference Data for The Multitemporal Land Cover Classification with MODIS Data of North Korea

  • Cha, Su-Young;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.23 no.5
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    • pp.483-491
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    • 2007
  • One of the major obstacles to classify and validate Land Cover maps is the high cost of acquiring reference data. In case of inaccessible areas such as North Korea, the high resolution satellite imagery may be used for reference data. The objective of this paper is to investigate the possibility of utilizing QuickBird high resolution imagery of North Korea that can be obtained from Google Earth data via internet for reference data of land cover classification. Monthly MODIS NDVI data of nine months from the summer of 2004 were classified into L=54 cluster using ISODATA algorithm, and these L clusters were assigned to 7 classes - coniferous forest, deciduous forest, mixed forest, paddy field, dry field, water, and built-up areas - by careful use of reference data obtained through visual interpretation of the high resolution imagery. The overall accuracy and Kappa index were 85.98% and 0.82, respectively, which represents about 10% point increase of classification accuracy than our previous study based on GCP point data around North Korea. Thus we can conclude that Google Earth may be used to substitute the traditional reference data collection on the site where the accessibility is severely limited.

TCP Congestion Control Algorithm using TimeStamp (TimeStamp를 이용한 TCP 혼잡제어 알고리즘)

  • 김노환
    • Journal of the Korea Society of Computer and Information
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    • v.5 no.3
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    • pp.126-131
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    • 2000
  • Through many users employ TCP of which the performance has been proved in Internet, but many papers Proposed to improve TCP performance according to varying network architecture. In Particular, BWDP(bandwidth-delay Product) grew larger because of the increasing delay in satellite link and the network's speed-up. To consider these increased bandwidth-delay product, it is suggested that TCP options include Window Scale option. TimeStamp option, and PAWS. Because TCP window size should be commonly high in the network with these increased bandwidth-delay product, the multiple decrease and linear increase scheme of current TCP would cause underflow and instability within network. Then TCP performance is reduced as a result. Thus, to improve TCP congestion control algorithm in the network which has large sized window, this paper proposes the congestion control scheme that controls window size by using TimeStamp option.

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Distributed beamforming with one-bit feedback and clustering for multi-node wireless energy transfer

  • Lee, Jonghyeok;Hwang, SeongJun;Hong, Yong-gi;Park, Jaehyun;Byun, Woo-Jin
    • ETRI Journal
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    • v.43 no.2
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    • pp.221-231
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    • 2021
  • To resolve energy depletion issues in massive Internet of Things sensor networks, we developed a set of distributed energy beamforming methods with one-bit feedback and clustering for multi-node wireless energy transfer, where multiple singleantenna distributed energy transmitters (Txs) transfer their energy to multiple nodes wirelessly. Unlike previous works focusing on distributed information beamforming using a single energy receiver (Rx) node, we developed a distributed energy beamforming method for multiple Rx nodes. Additionally, we propose two clustering methods in which each Tx node chooses a suitable Rx node. Furthermore, we propose a fast distributed beamforming method based on Tx sub-clustering. Through computer simulations, we demonstrate that the proposed distributed beamforming method makes it possible to transfer wireless energy to massive numbers of sensors effectively and rapidly with small implementation complexity. We also analyze the energy harvesting outage probability of the proposed beamforming method, which provides insights into the design of wireless energy transfer networks with distributed beamforming.

Software Library Design for GNSS/INS Integrated Navigation Based on Multi-Sensor Information of Android Smartphone

  • Kim, Youngki;Fang, Tae Hyun;Seo, Kiyeol
    • Journal of Positioning, Navigation, and Timing
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    • v.11 no.4
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    • pp.279-286
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    • 2022
  • In this paper, we designed a software library that produces integrated Global Navigation Satellite System (GNSS) / Inertial Navigation System (INS) navigation information using the raw measurements provided by the GNSS chipset, gyroscope, accelerometer and magnetometer embedded in android smartphone. Loosely coupled integration method was used to derive information of GNSS /INS integrated navigation. An application built in the designed library was developed and installed on the android smartphone. And we conducted field experiments. GNSS navigation messages were collected in the Radio Technical Commission for Maritime Service (RTCM 3.0) format by the Network Transport of RTCM via Internet Protocol (NTRIP). As a result of experiments, it was confirmed that design requirements were satisfied by deriving navigation such as three-dimensional position and speed, course over ground (COG), speed over ground (SOG), heading and protection level (PL) using the designed library. In addition, the results of this experiment are expected to be applicable to maritime navigation applications using smart device.

Implementation of pressure monitoring system(PMS) for ship's engine performance analysis(SEPA) based on the web (웹기반 선박엔진 성능분석용 압력모니터링 시스템 구현)

  • Yang, Hyun-Suk;Kwon, Hyuk-Joo;Lee, Sung-Geun
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.7
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    • pp.929-935
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    • 2014
  • This paper is study on the pressure monitoring system(PMS) for ship's engine performance analysis( SEPA) based on web, with high speed and accuracy. This system is composed of pressure sensor, monitoring module with multi channel A/D converter, TCP/IP and satellite internet communication system. Existing domestic products measure cylinder pressure when piston of first explosive cylinder reached TDC(the top dead center) point and then measure next cylinder pressure manually each angle divided by a constant rotating interval. But presented system monitors in the local and web computer, using pressure information transmitted from pressure sensor installed on each engine. In this system, it is possible to increase the accuracy of the engine performance analysis because not only each TDC points but cylinder pressures synchronized with the TDC points could be measured in real time, accurately. And therefore, it may be used in a various diagnosis of main engines, such as deviations of each cylinder maximum pressures(Pmax) and the TDC firing positions and combustion conditions.

Development of Spatial Landslide Information System and Application of Spatial Landslide Information (산사태 공간 정보시스템 개발 및 산사태 공간 정보의 활용)

  • 이사로;김윤종;민경덕
    • Spatial Information Research
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    • v.8 no.1
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    • pp.141-153
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    • 2000
  • The purpose of this study is to develop and apply spatial landslide information system using Geographic information system (GIS) in concerned with spatial data. Landslide locations detected from interpretation of aerial photo and field survey, and topographic , soil , forest , and geological maps of the study area, Yongin were collected and constructed into spatial database using GIS. As landslide occurrence factors, slope, aspect and curvature of topography were calculated from the topographic database. Texture, material, drainage and effective thickness of soil were extracted from the soil database, and type, age, diameter and density of wood were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the Landsat TM satellite image. In addition, landslide damageable objects such as building, road, rail and other facility were extracted from the topographic database. Landslide susceptibility was analyzed using the landslide occurrence factors by probability, logistic regression and neural network methods. The spatial landslide information system was developed to retrieve the constructed GIS database and landslide susceptibility . The system was developed using Arc View script language(Avenue), and consisted of pull-down and icon menus for easy use. Also, the constructed database can be retrieved through Internet World Wide Web (WWW) using Internet GIS technology.

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