• Title/Summary/Keyword: network-selection

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Prioritized Channel Contention Access Method for TDMA based MAC Protocol in Wireless Mesh Network (WMN에서 TDMA 기반 MAC Protocol을 위한 우선순위 채널 경쟁 접근 방법)

  • Yun, Sang-Man;Lee, Soon-Sik;Lee, Sang-Wook;Jeon, Seong-Geun;Lee, Woo-Jae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.9
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    • pp.1883-1890
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    • 2009
  • Existing MAC protocol can not show good performance in WMN environment. New MAC protocols is proposed because of Mobile Point's mobility, entire distributed environment, heavy traffic problems. This thesis proposes new channel contention method fur Mesh DCF. Mesh DCF uses ACH phase in TDMA frame to perform selection and elimination. Prioritized phases's count m and Fair Elimination phases's count n is determine contention level and make string probability to only one win the contention. Contention Number group's count K to determine the contention level in Fair Elimination Phase gives Fairness but make low probability to only one win the contention. It is sure that enough size of n and K can improve entire performance as result.

A Study on the Location Analysis of Public Service Facilities Considering Spatial Efficiency and Equity (효율성과 형평성을 고려한 공공시설 입지분석에 관한 연구 - 금산군 문화시설을 대상으로 -)

  • Yun, Jeong-Mi;Lee, Shin-Hoon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.2
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    • pp.1-10
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    • 2010
  • The purpose of this research is to establish location models for public service facilities considering efficiency as well as equity. And it suggests the method of spatial evaluation reflected the real world. Finally, this research is applied to the analysis on the optimum location of cultural facilities in Geumsan. This research adopts the expert survey for site selection factors and applys AHP for the relative weights. Secondly, it assorts the urban area by satellite image for the spatial analysis on the real world. Next, it adopts the Location-Allocation Model for the location evaluation and embodies the unequal population distribution according to the location model establishment. Finally, it conducts the more specific spatial analysis reflected the real world through the two methods applications; both spatial analysis(Grid analysis) and Network analysis.

QoS Enhancement Based on Link Quality in Tactical Data Link of KVMF (KVMF 전술네트워크에서 링크 품질에 기반한 QoS 향상 방안)

  • Kwon, Koo-Hyung;Jeong, Hyun-Sook;Lim, Won-Gi;Yoon, Young-Deuk;Kim, Sang-Soo;Lee, Sang-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.2
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    • pp.139-150
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    • 2014
  • This paper suggests an algorithm to improve QoS by using DTR bit employed in the MIL-STD-188-220 protocol, when there is a multi-path between source and destination in the environment of KVMF tactical network supporting NCW. The MIL-STD-188-220 protocol can evaluate the link quality relatively but it cannot support optimal path selection for QoS. In order to solve this problem, we design an algorithm for selecting path using topology table which reflects measured DTR of path after the completion of transmission. The performance of the proposed algorithm has been evaluated by OPNET simulator. As a result of the simulation, it is found that QoS of proposed algorithm is enhanced higher than that of the MIL-STD-188-220 in the aggravated communication environment.

Multiple-inputs Dual-outputs Process Characterization and Optimization of HDP-CVD SiO2 Deposition

  • Hong, Sang-Jeen;Hwang, Jong-Ha;Chun, Sang-Hyun;Han, Seung-Soo
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.11 no.3
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    • pp.135-145
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    • 2011
  • Accurate process characterization and optimization are the first step for a successful advanced process control (APC), and they should be followed by continuous monitoring and control in order to run manufacturing processes most efficiently. In this paper, process characterization and recipe optimization methods with multiple outputs are presented in high density plasma-chemical vapor deposition (HDP-CVD) silicon dioxide deposition process. Five controllable process variables of Top $SiH_4$, Bottom $SiH_4$, $O_2$, Top RF Power, and Bottom RF Power, and two responses of interest, such as deposition rate and uniformity, are simultaneously considered employing both statistical response surface methodology (RSM) and neural networks (NNs) based genetic algorithm (GA). Statistically, two phases of experimental design was performed, and the established statistical models were optimized using performance index (PI). Artificial intelligently, NN process model with two outputs were established, and recipe synthesis was performed employing GA. Statistical RSM offers minimum numbers of experiment to build regression models and response surface models, but the analysis of the data need to satisfy underlying assumption and statistical data analysis capability. NN based-GA does not require any underlying assumption for data modeling; however, the selection of the input data for the model establishment is important for accurate model construction. Both statistical and artificial intelligent methods suggest competitive characterization and optimization results in HDP-CVD $SiO_2$ deposition process, and the NN based-GA method showed 26% uniformity improvement with 36% less $SiH_4$ gas usage yielding 20.8 ${\AA}/sec$ deposition rate.

The meaning of experience and immersion to the diffusion of digital contents and consumption behavior based on arousal (디지털 콘텐츠의 확산과 공감 기반 소비행동에서의 경험과 몰입의 의미)

  • Kim, Yeonjeong
    • Journal of Digital Convergence
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    • v.11 no.12
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    • pp.387-392
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    • 2013
  • The purpose of this study investigate the main factors of the diffusion of digital contents and consumer's participation behavior, consumption culture and examine the experiential perspective to consumer's information selection behavior. In digital network, the social presence, challenge, self-presentation, arousal and emotional feeling were significant variables to flow experience. Experiential perspectives focused on the search of identity and self-determination were main basic perspective to explain the diffusion of digital contents, consumer participation. This research result applied to media and device strategy to up-coming digital convergence and adapted to product planning and development, user friendly navigation and emotional human-centered service module.

A Current Research Insight into Function and Development of Adjuvants (면역보조제의 작용 및 개발)

  • Sohn, Eun-Soo;Son, EunWha;Pyo, SuhkNeung
    • IMMUNE NETWORK
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    • v.4 no.3
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    • pp.131-142
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    • 2004
  • In recent years, adjuvants have received much attention because of the development of purified subunit and synthetic vaccines which are poor immunogens and require adjuvants to evoke the immune response. Therefore, immunologic adjuvants have been developed and testing for most of this century. During the last years much progress has been made on development, isolation and chemical synthesis of alternative adjuvants such as derivatives of muramyl dipeptide, monophosphoryl lipid A, liposomes, QS-21, MF-59 and immunostimulating complexes (ISCOMS). Biodegradable polymer microspheres are being evaluated for targeting antigens on mucosal surfaces and for controlled release of vaccines with an aim to reduce the number of doses required for primary immunization. The most common adjuvants for human use today are aluminum hydroxide and aluminum phosphate. Calcium phosphate and oil emulsions have been also used in human vaccination. The biggest issue with the use of adjuvants for human vaccines is the toxicity and adverse side effects of most of the adjuvant formulations. Other problems with the development of adjuvants include restricted adjuvanticity of certain formulations to a few antigens, use of aluminum adjuvants as reference adjuvant preparations under suboptimal conditions, non-availability of reliable animal models, use of non-standard assays and biological differences between animal models and humans leading to the failure of promising formulations to show adjuvanticity in clinical trials. The availability of hundreds of different adjuvants has prompted a need for identifying rational standards for selection of adjuvant formulations based on safety and sound immunological principles for human vaccines. The aim of the present review is to put the recent findings into a broader perspective to facilitate the application of these adjuvants in general and experimental vaccinology.

Highly Efficient Gene Expression in Rabbit Synoviocytes Using EBV-Based Plasmid (가토 윤활막 세포에서 EBV-Based 플라스미드를 사용한 효율적인 유전자 발현)

  • Kim, Jin Young;Oh, Sang Taek;Youn, JeeHee;Lee, Suk Kyeong
    • IMMUNE NETWORK
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    • v.4 no.3
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    • pp.190-197
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    • 2004
  • Background: Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic synovial inflammation which leads to joint destruction. Gene therapy of RA targets the players of inflammation or articular destruction. However, viral vectors have safety problems and side effects, while non-viral vectors suffer from inefficient gene transfer and fast loss of gene expression. To overcome the limits of non-vial vectors, an EBV-based plasmid which is known to exert prolonged high level gene expression can be used. Methods: pEBVGFP, pEBVIL-10, and pEBVvIL-10 were constructed by cloning GFP, IL-10, and vIL-10 genes into an EBV-based plasmid, respectively. The pGFP was used as a control plasmid. Each constructs were lipofected into HIG-82 rabbit synoviocytes. The expression of GFP was monitored by FACS and confocal microscopy. IL-10 and vIL-10 expressions were measured by ELISA. Results: GFP expression 2 days after transfection was achieved in 33.2% of cells. GFP-expressing cells transfected with pGFP decreased rapidly from 4 days after transfection and disappeared completely by 11 days. Cells transfected with pEBVGFP began to decrease slowly from 4 days. But GFP expression was detected for over 35 days. In addition, HIG-82 cells transfected with pEBVIL-10 ($44.6{\pm}1.5ng/ml$) or pEBVvIL-10 ($51.0{\pm}5.7ng/ml$) secreted these cytokines at high levels. High level cytokine production by hygromycin selection was maintained at least for up to 26 days after transfection. Conclusion: These results suggest that the EBV-based plasmid has a potential to improve non-viral gene transfer system and may be applicable to treat RA without the drawbacks of viral vectors.

Energy-efficient routing protocol based on Localization Identification and RSSI value in sensor network (센서 네트워크에서 RSSI 값과 위치 추정 기반의 에너지 효율적인 라우팅 프로토콜)

  • Kim, Yong-Tae;Jeong, Yoon-Su;Park, Gil-Cheol
    • Journal of Digital Convergence
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    • v.12 no.1
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    • pp.339-345
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    • 2014
  • This study has a purpose that improves efficiency of energy management and adaptation followed by movement of node better than the various early studied routing techniques. The purpose of this paper is the technique that uses RSSI value and location of sensor that is received by each sensor node to routing. This sduty does not save node information of 1-hop distance. And it solves energy-inefficient traffic problem that happens during data exchange process for middle node selection in close range multi hop transmission technique. The routing protocol technique that is proposed in this study selects a node relevant to the range of transmission which is set for RSSI value that is received by each node and selects the closest node as a middle node followed by location data. Therefore, it is for not exhaustion of node's energy by managing energy efficiently and cutting data transmission consuming until the destination node.

Determination of color samples uniformly distributed in printer gamut and its application to color reproduction (프린터 색역에 균등한 분포를 갖는 색표본 생성 및 색재현)

  • Lee, Cheol-Hee;Kim, Hee-Soo;Ahn, Suk-Chul;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.5
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    • pp.64-75
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    • 2000
  • This paper proposes a color sample selection method that produces a uniform distribution in the display gamut plus a color reproduction method for using a uniform color sample In contrast to the conventional method, the proposed uniform color samples are selected m CIELAB, a device-independent color space, instead of RGB (red, green, and yellow) or CMY (cyan, magenta, and yellow) space, device-dependent color spaces To evaluate the performance of the proposed color samples, they were applied to color space conversion using both a regression model and neural network As a result, in the case of a color sample of the same size, the color space conversion method using the proposed samples showed a lower color difference for color conversions using either neural or regression.

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Improved CNN Algorithm for Object Detection in Large Images

  • Yang, Seong Bong;Lee, Soo Jin
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.1
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    • pp.45-53
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    • 2020
  • Conventional Convolutional Neural Network(CNN) algorithms have limitations in detecting small objects in large image. In this paper, we propose an improved model which is based on Region Of Interest(ROI) selection and image dividing technique. We prepared YOLOv3 / Faster R-CNN algorithms which are transfer-learned by airfield and aircraft datasets. Also we prepared large images for testing. In order to verify our model, we selected airfield area from large image as ROI first and divided it in two power n orders. Then we compared the aircraft detection rates by number of divisions. We could get the best size of divided image pieces for efficient small object detection derived from the comparison of aircraft detection rates. As a result, we could verify that the improved CNN algorithm can detect small object in large images.