• 제목/요약/키워드: Remote Play

검색결과 138건 처리시간 0.022초

DISCRIMINATION OF EARLY MATURING PADDY RICE CROPS USING MULTI-TEMPORAL SAR IMAGES

  • Hong, Suk-Young;Jang, Min-Won;Kim, Yi-Hyun;Park, No-Wook
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.243-245
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    • 2007
  • This study was begun to classify the paddy fields by the rice varieties and to monitor the temporal change in rice growth using SAR backscatter coefficients $({\sigma}^{circ})$. For nine fine-beam mode images of Radarsat-1 SAR, a growing period time-series of backscatter coefficients was set up from April to October in 2005, and was compared with the field-measured rice growth parameters such as LAI (leaf area index), plant height, fresh and dry biomass, and water content in grain and plant for 45 parcels in Dangjin-gun, Chungcheongnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) were ranged from -18.17dB to -6.06dB and were lower than for medium-late maturing rice varieties during most of the growing season. At around the heading stage (July 30) for early-maturing rice, both rice crops showed the highest backscatter coefficient values and the difference was the greatest before harvesting early-maturing rice. The temporal difference in backscatter coefficients between rice varieties was expected to play a key role to identify early-maturing rice fields. On the other hand, comparison with field-measured rice growth parameters showed that the backscatter coefficients decreased or stayed on the plateau after heading stage even though the growth of rice canopy advanced.

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위성 데이터에 의한 선박 탐지: RADARSAT의 대기보정과 기하보정 (Ship Detection by Satellite Data: Radiometric and Geometric Calibrations of RADARS AT Data)

  • 양찬수
    • 해양환경안전학회지
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    • 제10권1호
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    • pp.1-7
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    • 2004
  • RADARSAT 위성은 레이더센서를 가지고 있어 전천후 및 주야불문이라는 두 가지 주요 이점을 가지고 있기 때문에, 선박탐지를 포함하는 해상감시 분야에 있어서 중요한 역할을 할 수 있다 그러나, 합성개구레이더의 이미징 시에 대기의 영향은 무시될 수 없으며, 또한 다양한 형태로 기하 변형이 발생하게 된다. 본 연구에서는, 레벨 1의 georeferenced SGX 데이터를 사용해서 RADARSAT의 합성개구레이더에 대한 대기/기하 보정을 실시하였다. 동일 이미지 내에서도, near range와 far range 세션의 비교를 위해서도 이와 같은 보정이 필요하다. 대기 보정은 후방산란에 대한 국소 조사부분과 입사각의 효과를 보정하여 수행되었으며, DN값은 beta nought와 sigma nought로 변환시켰다. 마지막으로 위성자세정보에서 추정되는 4점의 위치정보를 이용하여 자동 기하보정을 실시하였으며, 그 결과를 실제 좌표 값과 비교하였다. 오차는 위도방향으로 300m, 경도방향으로 260m범위 내에 있는 것으로 확인되었다. 이것은 추가로 지상기준점을 통해 보정될 수 있으며, 외해의 경우에는 적용 가능한 것으로 판단된다.

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시간 연속적인 스크린 이미지와 오디오의 스트리밍을 위한 멀티미디어 시스템 (Multimedia System for Streaming Time-Continuous Screen Images and Audio)

  • 황기태
    • 정보처리학회논문지B
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    • 제9B권2호
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    • pp.181-190
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    • 2002
  • 본 논문에서는 컴퓨터를 이용한 원격 강의, 원격 학습, 데모 화면 제작 등의 응용들에 필요한 동영상 멀티미디어 시스템을 제안한다. 이들 멀티미디어 응용들을 지원하기 위해서는 실세계 비디오를 다루는 동영상 시스템과는 달리, 시간적으로 변하는 컴퓨터 스크린과 오디오로 구성되는 동영상을 저작하고 재생하는 멀티미디어 시스템이 요구된다. 연속적으로 변하는 컴퓨터 스크린 이미지는 실세계 비디오의 크기와 영상 특성에 있어 차이점을 가지므로 기존의 MPEG 등과 같은 압축 알고리즘이 부적합하며 따라서 본 논문에서는 새로운 압축 알고리즘을 제안하고 멀티미디어 시스템을 설계 구현한 내용을 설명한다. 또한 본 논문에서 제안된 압축 알고리즘의 성능과 시스템 전체의 성능을 평가한 결과를 보인다.

중앙아시아 횡단철도의 건설과 그 현재적 함의 (The Construction of the Trans-Central Asian Railroad and Its Current Implications)

  • 이채문
    • 한국지역지리학회지
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    • 제15권1호
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    • pp.67-85
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    • 2009
  • 중앙아시아 횡단철도는 가스피해 횡단철도, 카자린스크 철도, 투르케스탄-시베리아 철도, 카자흐스탄 횡단철도 등으로 구성된다. 중앙아시아 인구의 약 1/5에 해당하는 주민들이 이 철도를 중심으로 거주하고 있으며, 중앙아시아 경제의 70%정도가 이 횡단철도를 기반으로 하고 있다. 유라시아의 심장지역으로 간주되고 있는 중앙아시아 횡단철도의 건설은 해양세력과의 지정학적 경쟁, 변경지역과 중심지역간의 연계 강화 및 중앙아시아 경제의 특성화가 주 목적이었다. 구소련의 붕괴 이후 중앙아시아 각국의 모든 철로망이 주로 러시아와 연계를 맺고 있지만, 그 외 인근국가들과의 연계망이 미흡한 상태에 있다. 장기적으로 중앙아시아 횡단철도의 발전을 위해 해결해야 할 과제가 많지만, 그럼에도 불구하고 동서로는 동아시아와 유럽을, 그리고 남북으로는 러시아/발틱해와 인도양/페르시아만을 연결하는 대륙의 교량으로서의 역할은 여전히 유효하다.

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Digital Conversion of Analogue Cadastral Maps of Kathmandu Metropolitan City

  • Baral, Toya Nath;Acharya, Babu Ram;Subedi, Nab Raj
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.973-977
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    • 2003
  • Land is the only immovable property that can be used, as a means for agricultural production as well as a means for mortgage for financing industrial or commercial enterprises. Spatial technologies play a key role in managing our land, water and natural resources. Cadastral data is a major component for the development of Land Information System. Therefore, systematic land registration system based on accurate and scientific cadastral map are found inevitable for poverty alleviation, good governance and women empowerment through security of their rights on property, as well as the planning and development of a sustainable environmental protection within Metropolitan city. Digital cadastral parcel is the fundamental spatial unit on which database is designed, created, maintained and operated. Availability of accurate and updated cadastral maps is a primary requisite for successful planning, policy formulating and maintenance of city utility services, which need cadastral and utility information together. Flawed cadastral maps can put land, revenue and taxation system at stake. Kathmandu the capital city of Nepal still is lacking utility maps combining cadastral information with the utility. There is an urgent need to have an effective, accurate and easy to access land revenue and utility services system within the urban areas which could be achieved after the production of reliable base maps and land registration system to guarantee land allocation and property rights which can well be achieved by digital conversion and correction of base cadastral maps. This paper highlights the drawbacks of the conventional cadastral maps and the possible advantages of digital cadastral maps over these. Also the problems, issues and implications during digital conversion and creating database of the same will be discussed.

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Infrared Estimation of Canopy Temperature as Crop Water Stress Indicator

  • Kim, Minyoung;Kim, Seounghee;Kim, Youngjin;Choi, Yonghun;Seo, Myungchul
    • 한국토양비료학회지
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    • 제48권5호
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    • pp.499-504
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    • 2015
  • Decision making by farmers regarding irrigation is critical for crop production. Therefore, the precision irrigation technique is very important to improve crop quality and yield. Recently, much attention has been given to remote sensing of crop canopy temperature as a crop water-stress indicator, because it is a scientifically based and easily applicable method even at field scales. This study monitored a series of time-variant canopy temperature of cucumber under three different irrigation treatments: under-irrigation (control), optimal-irrigation, and over-irrigation. The difference between canopy temperature ($T_c$) and air temperature ($T_a$), $T_c-T_a$, was calculated as an indicator of cucumber water stress. Vapor pressure deficit (VPD) was evaluated to define water stress on the basis of the temperature difference between leaf and air. The values of $T_c-T_a$ was negatively related to VPD; further, cucumber growth in the under- and over-irrigated fields showed water stress, in contrast to that grown in the optimally irrigated field. Thus, thermal infrared measurements could be useful for evaluating crop water status and play an important role in irrigation scheduling of agricultural crops.

Enhancing Business Continuity in the Oil and Gas Industry through Electronic Records Management System Usage to Improve Off-Site Working: A Narrative Review

  • Hawash, Burkan;Mokhtar, Umi Asma';Yusof, Zawiyah M.;Mukred, Muaadh
    • Journal of Information Science Theory and Practice
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    • 제10권2호
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    • pp.30-44
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    • 2022
  • The primary function of an electronic records management system (ERMS) is to support organisations in providing effective records management services by enabling efficient remote access to the organisations' records. This helps the organisation to continue running during emergency events, such as the COVID-19 pandemic. The need to study ERMS for accessing records remotely has increased dramatically, due to the increase in daily use. The situation arising from the COVID-19 pandemic has increased the need for implementing proper digital systems, such as ERMS, to enable efficient work processes and enhance business continuity. An ERMS has the potential to allow organisations to create records and workflows off-site. During a pandemic, the ability to structure processes digitally helps in maintaining operations remotely. This study aims to provide a narrative review of the ERMS literature with an emphasis on explaining the primary components of ERMS that act as enablers for the implementation of the system in the oil and gas sector of developing countries. The current study proposes ERMS roles and responsibilities that could enhance business continuity. The authors use a qualitative narrative review and analyse the literature related to this study and its findings. The results show that, in cases of risk or crises, staff members need to have easy access to their records and documents to remain productive. An ERMS allows professionals to remain active and work off-site. Thus, ERMS play a significant role in protecting an organisation's content through the monitoring and control over who has authorisation to access its records.

Long-term ecological monitoring in South Korea: progress and perspectives

  • Jeong Soo Park;Seung Jin Joo;Jaseok Lee;Dongmin Seo;Hyun Seok Kim;Jihyeon Jeon;Chung Weon Yun;Jeong Eun Lee;Sei-Woong Choi;Jae-Young Lee
    • Journal of Ecology and Environment
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    • 제47권4호
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    • pp.264-271
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    • 2023
  • Environmental crises caused by climate change and human-induced disturbances have become urgent challenges to the sustainability of human beings. These issues can be addressed based on a data-driven understanding and forecasting of ecosystem responses to environmental changes. In this study, we introduce a long-term ecological monitoring system in Korean Long-Term Ecological Research (KLTER), and a plan for the Korean Ecological Observatory Network (KEON). KLTER has been conducted since 2004 and has yielded valuable scientific results. However, the KLTER approach has limitations in data integration and coordinated observations. To overcome these limitations, we developed a KEON plan focused on multidisciplinary monitoring of the physiochemical, meteorological, and biological components of ecosystems to deepen process-based understanding of ecosystem functions and detect changes. KEON aims to answer nationwide and long-term ecological questions by using a standardized monitoring approach. We are preparing three types of observatories: two supersites depending on the climate-vegetation zones, three local sites depending on the ecosystem types, and two mobile deployment platforms to act on urgent ecological issues. The main observation topics were species diversity, population dynamics, biogeochemistry (carbon, methane, and water cycles), phenology, and remote sensing. We believe that KEON can address environmental challenges and play an important role in ecological observations through partnerships with international observatories.

극저전류자극이 손상된 토끼 뇌의 별아교세포 증식에 미치는 효과 (The Effects of Microcurrent Stimulation on the Astrocytes Proliferation at Injured Brain of Rabbit)

  • 김지성;민경옥
    • 대한물리치료과학회지
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    • 제9권3호
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    • pp.107-119
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    • 2002
  • Astrocyte, which shares the greatest part of the brain (about 25%), is a land of glial cell that composes the central nervous system along with microglia, ependymal cell and oligodendroglia. It has 7-9nm of fibers in its cytoplasma, which are composed of glial fibrillary acidic protein (GFAP) and vimentin. As for the functions of the astrocyte, it has, so far, been supposed that the astrocyte will play a cytoskeletal role in maintaining the structure of the cerebrum, play a role as a blood-brain barrier so that it can induce migration of the neuron in its development and substances in the blood cannot go into the nervous tissue, and a role of immunology and phagocytosis. However, it was revealed today that it will be a role in preventing expansion of injury by attaching itself to the connective tissue such as the vessel and the pia mater when the nervous tissue or the arachnoid is injured. Microcurrent stimulation can control current, on the basis of A unit. That is, with such devices using it, it is possible to sense, from the outside, the injured current(wound current) of the lesion and to change it into the normal current, thereby promoting the restoration of the cells. In order to examine the effects of microcurrent stimulation on the injured astrocytes in the rabbits, this study was conducted with 24 New Zealand White Rabbit as its subjects, which were divided into 8 animals of the experiment group and 16 animals of the control group. After the animals in the experiment group were fixed to the stereotaxic apparatus, their hair was removed and their premotor area(association area) perforated by the micro-drill for skull-perforation with the depth of 8mm from the scalp. In one week after the injury, 4 animals in the control group and 8 animals in the experiment group were sacrificed and examined with immunohistochemical method. And in three weeks, the remaining 4 animals in the control group and 8 animals in the experiment group were also sacrificed and examined with the same way. The conclusion has been drawn as follows : In the control group sacrificed in one week after the injury, the astrocytes somewhat increased, compared with the normal animals, and in the group sacrificed in three weeks after the injury, they increased more (p < 0.05). The experiment group A in one week showed a little increase, but there was no significant differences, but the experiment group in three weeks showed more increase, compared with the experiment group in one week (p < 0.05). The experiment group B in one week showed more increase than the control group or the experiment group A, and the experiment group in three weeks showed more increase than the experiment group in one week (p < 0.05). Among the astrocytes, fibrous astrocytes were mostly observed, increasing as they are close to the lesion, and decreasing as they are remote from it. The findings show that microcurrent can cause the astrocytes to proliferate and that it will be more effective to stimulate the cervical part somewhat remote from the lesion rather than to directly stimulate the part of the lesion. Thus, microcurrent stimulation can be one of the methods that can activate the reaction of astrocytes, which is one of the mechanism for treating cerebral injury with hemorrhage. Therefore, this study will be used as basic research data for promoting restoration of functions in the patient with injury in the central nervous system.

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ICESat-2 고도계 자료를 활용한 여름철 북극 융빙호 탐지 (Detection of Arctic Summer Melt Ponds Using ICESat-2 Altimetry Data)

  • 한대현;김영준;정시훈;심성문;김우혁;장은나;임정호;김현철
    • 대한원격탐사학회지
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    • 제37권5_1호
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    • pp.1177-1186
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    • 2021
  • 북극의 융빙호(melt pond)는 해빙 면적 감소 및 북극 빙권 변화에 중요한 역할을 하기 때문에 융빙호의 정확한 관측이 필요하다. 미국 NASA의 차세대 고도계 위성인 Ice, Cloud, and Land elevation Satellite-2 (ICESat-2)는 532 nm의 녹색 레이저를 발사한 뒤 반사되는 광자(photon)의 이동 시간을 계산하여 전 지구적으로 고해상도 고도 정보를 관측한다. ICESat-2는 현재 널리 쓰이고 있는 고도계인 CryoSat-2에 비해 세밀한 관측이 가능하기 때문에, Cryosat-2에서 관측할 수 없는 작은 규모의 융빙호를 탐지할 수 있을 것으로 기대된다. ICESat-2의 기본적인 정보로는 표면 높이(surface height)와 반사되는 광자의 수(photon count)가 있다. 본 연구에서는 각 ICESat-2 지점을 중심으로 10 m 길이의 segment를 생성하여 segment 내의 높이 표준편차와 총 광자 수를 활용한 융빙호 탐지 알고리즘을 제시하였다. 융빙호는 표면이 해빙에 비해 매끄러워서 높이의 분산이 적으므로 높이의 표준편차를 활용하여 일차적으로 융빙호와 해빙을 분류하였다. 그 다음으로는 융빙호 중에서 표면이 물인 융빙호와 얼음 표면인 융빙호를 분류하였다. 표면이 물인 융빙호는 광자를 많이 흡수하기 때문에 단위 segment 내에서 반사되어 수집된 광자의 수가 적으며, 반대로 얼음으로 덮인 융빙호는 반사되는 광자의 수가 많다. 결과적으로 본 연구에서 제시하는 융빙호 탐지 방법을 통해 물과 얼음으로 덮인 융빙호를 구별하여 탐지할 수 있다. Sentinel-2 광학 영상을 활용하여 융빙호 탐지 결과의 정성적인 분석을 하였다. 그 결과 Sentinel-2 광학 영상으로 구분하기 어려운 표면이 물인 융빙호와 얼음인 융빙호를 ICESat-2를 활용해 효과적으로 분류하였다. 마지막으로 고도계 위성 및 광학 영상을 활용한 융빙호 탐지의 고찰을 서술하였다.