• Title/Summary/Keyword: Selection efficiency

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Plant Species Selection Program for Ecological Restoration of Coastal Reclaimed Land -Focused on the Dumped Soil Area at Inchon Airport- (해안간척지의 생태적 환경복원을 위한 식물 선정에 관한 연구 -인천공항 사토장지역을 중심으로-)

  • Bae, Young-Hun;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.3
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    • pp.66-74
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    • 2001
  • The main purpose of this thesis is to select the appropriate plants for the ecological restoration of coastal land. The soil and vegetation environment survey of the beach where the halophytes live now was executed for the sake. Firstly, the soil survey was done by the physical and chemical survey of beach soil and dumped soil. The soil is mostly sandy loam and sandy clay loam which has silty much. The beach soil where the salt plants live has more organic matters in the content than dumped soil because of the influx of the dead halophytes, a pioneer plant to this area. Secondly the vegetation survey was executed by the halophytes survey in the beach area in order to select the appropriate plants for ecological restoration. The shows two different areas in the vegetation divided by the salt density of soil. Artemisia fukudo, Juncus haenkei, Carex pumila, Silene armeia, Polyponum aviculare etc live in the less salt density area and it doesnt show collected. Salicornia herbacea, Suaeda asparagoides, Aster tripolium, Limonium tetragonum, Suaeda maritima, Scirus fluvitilis, Phragmtes communis, Suaeda japonica, Zoysia sinica etc halophytes live in the more salt density area and there are a few advent plant but many collected. So the salt density of soil limits the vegetation. The selection of appropriate plants for the ecological restoration programs was designed with 3 different standards considering the salt density of soil in the dumped soil area. The plan selection guidelines of thick salt density due to the salt density of soil, and economical efficiency and maintenance because the area is large. The guidelines of middle salt density area were made considering economical efficiency and maintenance because there are salt as well, and it is effective for the scenery if they have normal ecology but their leaves have good color and the flowers are beautiful. However I suggest beautiful flowery plants for the neutral plan area because this area is the entry point of the airport so the view is very important.

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Dynamic States Consideration for Next Hop Nodes Selection Method to Improve Energy Efficiency in LEAP based Wireless Sensor Networks (LEAP기반의 무선 센서 네트워크에서 가변적 상태를 고려한 에너지 효율적 다음 홉 노드 선택 기법)

  • Nam, Su-Man;Cho, Tae-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.23 no.6
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    • pp.558-564
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    • 2013
  • Wireless sensor networks (WSNs) contain limited energy resources and are left in open environments. Since these sensor nodes are self-operated, attacks such as sinkhole attacks are possible as they can be compromised by an adversary. The sinkhole attack may cause to change initially constructed routing paths, and capture of significant information at the compromised node. A localized encryption and authentication protocol (LEAP) has been proposed to authenticate packets and node states by using four types of keys against the sinkhole attack. Even though this novel approach can securely transmits the packets to a base station, the packets are forwarded along the constructed paths without checking the next hop node states. In this paper, we propose the next hop node selection method to cater this problem. Our proposed method evaluates the next hop node considering three factors (i.e., remaining energy level, number of shared keys, and number of filtered false packets). When the suitability criterion for next hop node selection is satisfied against a fix threshold value, the packet is forwarded to the next hop node. We aim to enhance energy efficiency and a detour of attacked areas to be effectively selected Experimental results demonstrate validity of the proposed method with up to 6% energy saving against the sinkhole attack as compared to the LEAP.

A Study on The Major Environmental Effecting Factors for The Selection Environment-Friendly Railway Corridor (환경 친화적 철도노선대 선정을 위한 주요환경 영향인자에 관한 연구)

  • Kim, Dong-Ki
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.2
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    • pp.132-138
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    • 2009
  • The energy efficiency and environment-friendly aspect of the railway system would be superior to other on-land transportation systems. In a preliminary feasibility study stage and selection of optimal railway corridor, the energy efficiency and problems related to environment are usually not considered. For the selection of optimal railway corridor, geographical features and facility of management are generally considered. Environment effect factors for the selection of environment-friendly railway corridor are focused and studied in this paper. In this study, various analysis of opinion of specialists (railway, environment, transport, urban planning, survey) and the guideline for construction of environment-friendly railway were accomplished. From these results of various analysis, 7 major categories (topography/geology, flora and fauna, Nature Property, air quality, water quality, noise/vibration, visual impact/cultural assets) were extracted. To select environment friendly railway corridors, many alternatives should be compared optimal corridor must be selected by a comprehensive assessment considering these 7 categories. The investment for railway systems can be encouraged by the considering of main environmental effect factor evaluated with the modified environmental weight factors for environment-friendly railway construction.

An Adaptive Data Compression Algorithm for Video Data (사진데이타를 위한 한 Adaptive Data Compression 방법)

  • 김재균
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.2
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    • pp.1-10
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    • 1975
  • This paper presents an adaptive data compression algorithm for video data. The coling complexity due to the high correlation in the given data sequence is alleviated by coding the difference data, sequence rather than the data sequence itself. The adaptation to the nonstationary statistics of the data is confined within a code set, which consists of two constant length cades and six modified Shannon.Fano codes. lt is assumed that the probability distributions of tile difference data sequence and of the data entropy are Laplacian and Gaussion, respectively. The adaptive coding performance is compared for two code selection criteria: entropy and $P_r$[difference value=0]=$P_0$. It is shown that data compression ratio 2 : 1 is achievable with the adaptive coding. The gain by the adaptive coding over the fixed coding is shown to be about 10% in compression ratio and 15% in code efficiency. In addition, $P_0$ is found to he not only a convenient criterion for code selection, but also such efficient a parameter as to perform almost like entropy.

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A New Selection Strategy of High Redshift Quasars: Medium-Band Observation with SQUEAN

  • Jeon, Yiseul;Im, Myungshin;Pak, Soojong
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.78.3-78.3
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    • 2015
  • About 70 high redshift quasars with $z{\geq}5$ have been discovered through combinations of standard broad-band filters to distinguish them from contaminating sources. However, among the discovered quasars so far, there is a redshift gap at $5{\leq}z{\leq}6$ due to the limitation of traditional filter sets and selection techniques. To understand the early mass growth of supermassive black holes and the final stage of the cosmic reionization, it is important to find a statistically meaningful sample of quasars with various physical properties. Here we suggest a new selection technique of high redshift quasars using medium-band filters: nine filters with bandwidths of 50nm and central wavelengths from 625 to 1025nm. Photometry with these medium-bands traces the spectral energy distribution (SED) of a source, similar to spectroscopy with R~15. We installed these filters to SED camera for QUasars in EArly uNiverse (SQUEAN) on the 2.1m telescope at McDonald Observatory, and conducted test observations of known high redshift quasars at $4.7{\leq}z{\leq}6.1$ and also dwarf stars for comparison. We found differences in SED shapes between high redshift quasars and dwarf stars, determined their locations on color-color diagrams, and demonstrated that the medium-band filters can enhance the efficiency of selecting robust quasar candidates in this redshift range. In this poster, we propose an effective selection method of high redshift quasars using these medium-band filters and discuss its effect on our high redshift quasar survey.

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The Importance Analysis of the Selection Factors for IPTV using AHP (계층적 분석방법을 활용한 IPTV 선택요인의 중요도 분석)

  • Ha, Gui-Ryong;Lee, Kyung-Tak
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.814-825
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    • 2009
  • This paper is to analyze the relative weight and the priority order of the selection factors for IPTV. To obtain the goal this paper, firstly, the selecting factors for IPTV were identified and conceptualized on reviewing previous literatures. And this paper proposed the hierarchy model using the factor analysis on IPTV users. and utilized AHP in analysis method. Secondly, AHP model constructed 4 higher factors, and 15 lower factors. The higher factors were 'Quality Acceptance', 'Social Effect', 'Using Motive' and 'Individual Psychology'. Results of this study show that relative weights among factors IPTV selection were founded as 'Quality Acceptance(33.0%)', 'Utilization Motive(31.8%)', 'Individual Psychology(21.3%)' and 'Social Influence(13.9%)'. Economic efficiency takes the top rank in sub-criteria included 15 factors and than convenience, amount of information, discrimination, self-efficacy, innovation, relative advantage in order listed. For the generalization of the research results, further researchs are needed to investigate intended use of IPTV on other method of analysis.

Conditions for Selection of Targeted Colonies in the Primary Cells

  • Chang, Mi-Ra;Oh, Keon-Bong;Lee, Kyung-Kwang;Han, Yong-Mahn
    • Proceedings of the KSAR Conference
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    • 2003.06a
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    • pp.55-55
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    • 2003
  • The random insertion of useful gene in genome has been a common method to produce transgenic animals. This method is inefficient for induction of high levels gene expression in transgenic animals. To improve this limit, we tried to develop the system which target the gene at the specific genomic region. Thus, in our experiment, the vector system to target the human thrombopoietin (TPO) gene was developed. Targeting vector including TPO, neo and DT genes was transfrcted into bovine embryonic fibroblasts (bEF) or bovine ear skin fibroblasts (bESF). First of all, we determined concentration of the geneticin (G418) for selection of transfected cell lines. Our results showed that 1200 and 900 $\mu\textrm{g}$/ml of G418 were the most proper for selection of transfscted bEF and bESF cells. In this study, lipofectamine was used as a transfection reagent. Thus, the proper ratio of DNA:lipofectamine for transfection was also required to elevate targeting efficiency in primary mammalian cells. Our result indicates that the most proper ratios of DNA:lipofectamine were 4:2 and 1:2 in bEF and bESF cells. According to the optimized these conditions, single colonies were picked following transfection and were analyzed by PCR. More than 90% of the single colonies have TPO gene. However, there were no colonies with targeted TPO at the specific genomic region. Therefore, further experiments to select the specifically targeted colonies and to find more efficient methods such as reducing selection time and shortening a size of TPO gene are required.

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A Cluster Head Selection Algorithm Adopting Sensor Density on Wireless Sensor Networks (무선 센서 네트워크상에서 센서간의 밀도를 고려한 클러스터 헤드 선정 알고리즘)

  • Jung, Eui-Hyun;Lee, Sung-Ho;Park, Yong-Jin;Hwang, Ho-Young;Hur, Moon-Haeng
    • The KIPS Transactions:PartC
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    • v.13C no.6 s.109
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    • pp.741-748
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    • 2006
  • Due to the continuous development of sensor technology, Wireless Sensor Networks are rapidly growing and are expected to be applied to various applications. One of the most important factors in Wireless Sensor Networks is energy-efficient management of network resources. For this purpose, a lot of researches have been ongoing in the development of energy-efficient routing protocol. In this paper, a cluster head selection algorithm considering node density in addition to the cluster head selection algorithm of LEACH-C is proposed and simulated. This algorithm gives nearly the same computational speed compared to that of LEACH-C and shows improvement of network lifetime about 11% better than LEACH-C. The simulation result shows that consideration of density as well as distance between nodes in cluster head selection can be more energy-efficient than considering only the distance between nodes as LEACH-C in energy usage of Wireless Sensor Networks.

Channel Selection for the Coexistence of Different Bandwidth Systems in TV White Space (TV 화이트 스페이스에서 서로 다른 대역폭을 가진 시스템들의 공존을 위한 적응적 채널 선택 기법)

  • Noh, Go-San;Bang, Keuk-Joon;Hong, Dae-Sik
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.3
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    • pp.1-7
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    • 2012
  • In this paper, we consider a channel selection method for the coexistence of heterogeneous systems in the TV white space (TVWS). First, we define the target heterogeneous system structure. Then, under the defined system structure, we discuss how the heterogeneous systems share the TVWS channels. Specifically, the heterogeneous systems having different bandwidths cannot use the TVWS channels due to the lack of wideband channels when only narrowband channels are remained. Hence, in order to minimize the blocking from the different bandwidth problem, we propose a channel selection method for the narrowband systems to firstly occupy the narrowband channels rather than the wideband channels. The proposed narrowband-first channel selection is shown to enhance the spectral efficiency of the TVWS, especially in the IEEE 802.19.1 wireless coexistence system.

Antenna Selection Scheme for BD Beamforming-based Multiuser Massive MIMO Communication Systems (BD 빔포밍을 이용한 다중 사용자 기반 거대 안테나 통신 시스템용 안테나 선택 기법)

  • Ban, Tae-Won;Jung, Bang Chul;Park, Yeon-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.433-436
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    • 2013
  • Massive MIMO communication system with huge antennas has been attracting intensive attention as one of key technologies to increase the spectral efficiency. Many previous studies investigated single user Massive MIMO scheme in cellular downlink. Recently, however, intensive researches on multiuser-based Massive MIMO are performed to overcome the problem caused by the limited number of antennas in mobile stations. Although the Massive MIMO scheme based on huge number of antennas inevitably causes hardware and computational complexity in baseband and radio frequency (RF) elements, the problem can be mitigated without serious performance degradation by limiting the number of baseband and RF elements below the number of transmit antennas of base station and opportunistically selecting transmit antennas according to channel states, where the number of selected antennas corresponds to the number of baseband and RF elements in base station. Accordingly, this paper proposes a simple antenna selection scheme for multiuser-based Massive MIMO systems. Our simulation results indicate that the proposed antenna selection scheme can achieve comparable performance to the conventional scheme without antenna selection.

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