• Title/Summary/Keyword: Coverage Planning

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WCDMA Radio Network Planning Issues

  • 임종태
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.4
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    • pp.25-32
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    • 2002
  • 우리의 이동통신 시장은 초기 AMPS를 거쳐 IS-95 A/B, CDMA2000 1X 그리고, EV-DO까지 많은 관심과 기술의 발전 속에 진화되어왔다. 이제, 2, 3 세대 이동통신 시스템을 발판으로 다양한 멀티 미디어 서비스를 선보일 WCDMA 시스템을 상용화하기에 이르렀다. 따라서, 추후 시장의 요구에 발맞추어 신뢰성 있는 고속 데이터 서비스를 구현할 수 있도록, WCDMA 관련 기술들에 관한 중점적인 논의가 이루어져야 할 것이다. 본 고에서는 WCDMA의 망 성능(coverage, capacity, quality of service)을 향상시키기 위한 망 설계 주요 사항에 대하여 기술하고자 한다.

Comparison of Radio Wave Propagation Models for Mobile Networks

  • Altayeva, Aigerim Bakatkaliyevna;Cho, Young Im
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.15 no.3
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    • pp.192-199
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    • 2015
  • Heterogeneous cellular networks are gaining momentum in industry and the research community, and are attracting the attention of standard bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are to increase the capacity and coverage of cellular networks. In this article, we provide an overview of expansion strategies, optimal locations of base stations with different characteristics, and radio-planning models.

KOMPSAT - Urban Application Center

  • Kressler F.P.;Kim Y.S.;Steinnocher K.;Triebnig G.
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.158-161
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    • 2004
  • KOMPSAT-2, to be launched in 2005, will be a long awaited addition to the existing high-resolution satellite sensors. The use of download facilities in Europe will greatly increase its capacity without loosing any coverage over Korea. In this paper the concept for an Urban Application Center is presented. It is part of the proposed Regional Application Center which is dedicated to archiving and distributing KOMPSAT-2 images. The Urban Application Center will offer services derived from KOMPSAT-2. Its aim is to promote the use of KOMPSAT-2 data and increase the general awareness and acceptance of satellite data.

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Dose Planning Study of Target Volume Coverage with Intensity-Modulated Radiotherapy for Nasopharyngeal Carcinoma: Penang General Hospital Experience

  • Vincent Phua, Chee Ee;Tan, Boon Seang;Tan, Ai Lian;Eng, Kae Yann;Ng, Bong Seng;Ung, Ngie Min
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2243-2248
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    • 2013
  • Background: To compare the dosimetric coverage of target volumes and organs at risk in the radical treatment of nasopharyngeal carcinoma (NPC) between intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT). Materials and Methods: Data from 10 consecutive patients treated with IMRT from June-October 2011 in Penang General Hospital were collected retrospectively for analysis. For each patient, dose volume histograms were generated for both the IMRT and 3DCRT plans using a total dose of 70Gy. Comparison of the plans was accomplished by comparing the target volume coverage (5 measures) and sparing of organs at risk (17 organs) for each patient using both IMRT and 3DCRT. The means of each comparison target volume coverage measures and organs at risk measures were obtained and tested for statistical significance using the paired Student t-test. Results: All 5 measures for target volume coverage showed marked dosimetric superiority of IMRT over 3DCRT. V70 and V66.5 for PTV70 showed an absolute improvement of 39.3% and 24.1% respectively. V59.4 and V56.4 for PTV59.4 showed advantages of 18.4% and 16.4%. Moreover, the mean PTV70 dose revealed a 5.1 Gy higher dose with IMRT. Only 4 out of 17 organs at risk showed statistically significant difference in their means which were clinically meaningful between the IMRT and 3DCRT techniques. IMRT was superior in sparing the spinal cord (less 5.8Gy), V30 of right parotid (less 14.3%) and V30 of the left parotid (less 13.1%). The V55 of the left cochlea was lower with 3DCRT (less 44.3%). Conclusions: IMRT is superior to 3DCRT due to its dosimetric advantage in target volume coverage while delivering acceptable doses to organs at risk. A total dose of 70Gy with IMRT should be considered as a standard of care for radical treatment of NPC.

Analysis of Korean Medicine Market and Strategies after the conclusion of a Korea-China FTA through the Scenario Planning Approach (시나리오 플래닝기법을 활용한 한.중 FTA 체결이후의 한의서비스 시장 분석 및 대응전략)

  • Kim, Jung-Min;Lim, Byung-Mook;Shin, Mi-Sook
    • Journal of Society of Preventive Korean Medicine
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    • v.16 no.2
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    • pp.53-65
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    • 2012
  • Objectives : This study aimed to analyze the fundamentals of a Korea-China FTA and suggest strategies for Korean medicine market that correspond with each scenario selected from foreseen circumstances after the conclusion of the FTA through the scenario planning, which is one of management techniques. Methods : Four scenarios have been established by means of key questions : the scope of FTA, health care policies, and the combination of western medicine(WM) and Korean medicine(KM). Each scenario is defined as the Maximized Competitive Market, Neutral Market, General Completive Market, and Conservative Market. This study suggests brand marketing, extending of health insurance coverage, launching local network, and strategy for Korean medicine based health promotion programs. Results and Conclusions : Although Korean medicine could be prompted by the trade policies between countries, related studies are very limited. Therefore, more research is needed to suggest the detailed strategies for change of Korean medicine market through various strategic analysis tools.

A Study on Development of Wind-Rose software for Planning Runway Direction at an Airport (활주로 방향설정을 위한 풍배도 프로그램의 개발 연구)

  • Sin, D.J.;Kim, D.H.
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.17 no.1
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    • pp.39-45
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    • 2009
  • An Analysis of wind is essential for planning runway direction. As a general rule, the principal traffic runway at an airport should be oriented as closely as practicable in the direction of the prevailing wind. Aircraft are able to maneuver on a runway as long as the wind component at right angles to the direction of landing and taking-off, the cross wind component, is not excessive. ICAO recommends that runway be oriented so that aircraft may be landed at least 95% of the time with allowable cross wind components not exceeding specified limits based upon the airport reference field length. Based on the recommendation, the direction of the runway or runways at an airport can be determined through graphical vector analysis on wind rose. This study is to develop the wind-rose software for planning the optimum runway direction at an airport with the raw wind data based on reliable wind distribution statistics that extend over as long as a period as possible, preferably of not less than 5 years.

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Design of Smart City Considering Carbon Emissions under The Background of Industry 5.0

  • Fengjiao Zhou;Rui Ma;Mohamad Shaharudin bin Samsurijan;Xiaoqin Xie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.4
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    • pp.903-921
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    • 2024
  • Industry 5.0 puts forward higher requirements for smart cities, including low-carbon, sustainable, and people-oriented, which pose challenges to the design of smart cities. In response to the above challenges, this study introduces the cyber-physical-social system (CPSS) and parallel system theory into the design of smart cities, and constructs a smart city framework based on parallel system theory. On this basis, in order to enhance the security of smart cities, a sustainable patrol subsystem for smart cities has been established. The intelligent patrol system uses a drone platform, and the trajectory planning of the drone is a key problem that needs to be solved. Therefore, a mathematical model was established that considers various objectives, including minimizing carbon emissions, minimizing noise impact, and maximizing coverage area, while also taking into account the flight performance constraints of drones. In addition, an improved metaheuristic algorithm based on ant colony optimization (ACO) algorithm was designed for trajectory planning of patrol drones. Finally, a digital environmental map was established based on real urban scenes and simulation experiments were conducted. The results show that compared with the other three metaheuristic algorithms, the algorithm designed in this study has the best performance.

Comparison of Dosimetric Parameters Based on Beam Arrangement Changes in HA-WBRT by Using VMAT Technique: A Phantom Study (VMAT 기법을 활용한 HA-WBRT에서 빔 배열 변화에 따른 선량학적 인자 비교: 팬텀 연구)

  • Sung-Kuk Park;Dong-Hyun Kim
    • Journal of radiological science and technology
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    • v.47 no.4
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    • pp.271-278
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    • 2024
  • This study aimed to evaluate the impact of changes in beam arrangement and arc counts on dosimetric factors in volumetric modulated arc therapy (VMAT) inverse radiation therapy planning for hippocampal-avoidance whole brain radiation therapy (HA-WBRT) by using the Elekta Monaco radiation therapy planning system (RTPs). For coplanar VMAT, both the arc per beam (APB) method and the beam determined arc(BDA) method, which is determined by the number of beams, were applied. For non-coplanar VMAT, the BDA method was utilized, and a total of 9 treatment plans were established by varying the arc counts. All radiation therapy plans met the radiation oncology group (RTOG) 0933 protocol standards, and 14 dosimetric factors were compared and analyzed. The results showed that the BDA-NC VMAT method demonstrated superior performance in terms of planning target volume (PTV) coverage and protection of normal organs, while APB-VMAT was advantageous in terms of hippocampal protection, monitor unit and delivery time. This study is expected to contribute to the efficient establishment of HA-WBRT plans considering the changes in beam arrangement and rotation arc numbers in Monaco RTPs.

The effect of photon energy on intensity-modulated radiation therapy (IMRT) plans for prostate cancer

  • Sung, Won-Mo;Park, Jong-Min;Choi, Chang-Heon;Ha, Sung-Whan;Ye, Sung-Joon
    • Radiation Oncology Journal
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    • v.30 no.1
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    • pp.27-35
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    • 2012
  • Purpose: To evaluate the effect of common three photon energies (6-MV, 10-MV, and 15-MV) on intensity-modulated radiation therapy (IMRT) plans to treat prostate cancer patients. Materials and Methods: Twenty patients with prostate cancer treated locally to 81.0 Gy were retrospectively studied. 6-MV, 10-MV, and 15-MV IMRT plans for each patient were generated using suitable planning objectives, dose constraints, and 8-field setting. The plans were analyzed in terms of dose-volume histogram for the target coverage, dose conformity, organs at risk (OAR) sparing, and normal tissue integral dose. Results: Regardless of the energies chosen at the plans, the target coverage, conformity, and homogeneity of the plans were similar. However, there was a significant dose increase in rectal wall and femoral heads for 6-MV compared to those for 10-MV and 15-MV. The $V_{20Gy}$ of rectal wall with 6-MV, 10-MV, and 15-MV were 95.6%, 88.4%, and 89.4% while the mean dose to femoral heads were 31.7, 25.9, and 26.3 Gy, respectively. Integral doses to the normal tissues in higher energy (10-MV and 15-MV) plans were reduced by about 7%. Overall, integral doses in mid and low dose regions in 6-MV plans were increased by up to 13%. Conclusion: In this study, 10-MV prostate IMRT plans showed better OAR sparing and less integral doses than the 6-MV. The biological and clinical significance of this finding remains to be determined afterward, considering neutron dose contribution.

Convolution-Superposition Based IMRT Plan Study for the PTV Containing the Air Region: A Prostate Cancer Case (Convolution-Superposition 알고리즘을 이용한 치료계획시스템에서 공기가 포함된 표적체적에 대한 IMRT 플랜: 전립선 케이스)

  • Kang, Sei-Kwon;Yoon, Jai-Woong;Park, Soah;Hwang, Taejin;Cheong, Kwang-Ho;Han, Taejin;Kim, Haeyoung;Lee, Me-Yeon;Kim, Kyoung Ju;Bae, Hoonsik
    • Progress in Medical Physics
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    • v.24 no.4
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    • pp.271-277
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    • 2013
  • In prostate IMRT planning, the planning target volume (PTV), extended from a clinical target volume (CTV), often contains an overlap air volume from the rectum, which poses a problem inoptimization and prescription. This study was aimed to establish a planning method for such a case. There can be three options in which volume should be considered the target during optimization process; PTV including the air volume of air density ('airOpt'), PTV including the air volume of density value one, mimicking the tissue material ('density1Opt'), and PTV excluding the air volume ('noAirOpt'). Using 10 MV photon beams, seven field IMRT plans for each target were created with the same parameter condition. For these three cases, DVHs for the PTV, bladder and the rectum were compared. Also, the dose coverage for the CTV and the shifted CTV were evaluated in which the shifted CTV was a copied and translated virtual CTV toward the rectum inside the PTV, thus occupying the initial position of the overlap air volume, simulating the worst condition for the dose coverage in the target. Among the three options, only density1Opt plan gave clinically acceptable result in terms of target coverage and maximum dose. The airOpt plan gave exceedingly higher dose and excessive dose coverage for the target volume whereas noAirOpt plan gave underdose for the shifted CTV. Therefore, for prostate IMRT plan, having an air region in the PTV, density modification of the included air to the value of one, is suggested, prior to optimization and prescription for the PTV. This idea can be equally applied to any cases including the head and neck cancer with the PTV having the overlapped air region. Further study is being under process.