• Title/Summary/Keyword: diversity combining

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Performance Analysis of Cooperative Diversity on the Usage of Opportunistic Relay (기회주의적인 중계기 사용에 대한 협력 다이버시티의 성능 분석)

  • Kim, Tae-Wook;Kong, Hyung-Yun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.7-12
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    • 2014
  • The data forwarding transmission is an important function of the relay in cooperative communication in wireless communication systems. However, additional relay cause the waste of power consumption and cost. Therefore, in this paper, we consider how to use the user mobile devices in stead of relays to deal with this problem. In this paper, we proposed the protocol that divide each relay into two states of idle and non-idle. The receiver has two functions of base station and user mobile device. In this case, it is possible that no additional cost, and improve the spectral efficiency and network capacity. We verified BER performance for the proposed protocol over Rayleigh fading through Monte-Carlo simulation.

A Study on Mixed RP/SP Models of Demand Forecasting for Rail Rapid Transit (급행철도 수요예측을 위한 RP와 SP 결합모형에 관한 연구)

  • Bae, Choon Bong;Jung, Byung Doo;Hwang, Young Ki;Kim, Hyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.5D
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    • pp.671-677
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    • 2011
  • A diversity of railway network function enhancement projects such as the double tracking, electrification, and direct operation have been actively executed to improve the railway service. When the new rapid transit is provided, how many people will use it instead of other transports? How will the railway choice behavior be changed? Accordingly, in this paper, the applicability of diverted travel demand forecast methods, by Revealed Preference(RP) and Stated Preference(SP) data was reviewed for Daegu metropolitan rail rapid transit service. As the result of combining RP and SP data, including the sequential and simultaneous approach, the total travel time and travel cost parameters are of the right sign and are highly significant. The simultaneous approach is more efficient in terms of the estimation of coefficients. In particular, methods to improve validity of the Mixed RP/SP models, when RP data is used proportionally, the diverted travel demand can be easily identified by railway fare and travel time service level. Therefore, it is considered that this will practically apply even in other regions as well as Daegu metropolitan railway.

Comparison of Different PCR-Based Genotyping Techniques for MRSA Discrimination Among Methicillin-Resistant Staphylococcus aureus Isolates

  • Kim, Keun-Sung;Seo, Hyun-Ah;Oh, Chang-Yong;Kim, Hong
    • Journal of Microbiology and Biotechnology
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    • v.11 no.5
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    • pp.788-797
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    • 2001
  • The usefulness of three PCR methods were evaluated for the epidemiological typing of Staphylococcus aureus: an enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), repetitive extragenic palindromic element PCR (REP-PCR), and 16S-23S intergenic spacer PCR (ITS-PCR). The analysis was performed using a collection of S. aureus strains comprised of 6 reference and 79 isolates from patients with various diseases. Among the 85 S. aureus strains tested, 6 references and 6 isolates were found to be susceptible to methicillin, whereas the remaining 73 isolates were resistant to it. PCR methods are of special concern, as conventional phenotypic methods are unable to clearly distinguish among methicillin-resistant S. aureus (MRSA) strains. The ability of the techniques to detect different unrelated types was found to be as follows: ERIC-PCR, 19 types; REP-PCR, 36 types; and ITS-PCR, 14 types. On the basis of combining the ERIC, REP, and ITS fingerprints, the 85 S. aureus strains were grouped into 56 genetic types (designated G1 to G56). The diversities for the 85 S. aureus strains, calculated according to Simpson\`s index, were 0.88 for an ERIC-PCR, 0.93 for a REP-PCR, and 0.48 for an ITS-PCR, and the diversity increased up to 0.97 when an ERIC-PCR and REP-PCR were combined. The above discrimination indices imply that the genetic heterogeneity of S. aureus strains is high. Accordingly, this study demonstrates that DNA sequences from highly conserved repeats of a genome, particularly a combination of ERIC sequences and REP elements, are a convenient and accurate tool for the subspecies-specific discrimination and epidemiologic tracking of S. aureus.

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Shore-to-sea Maritime Visible Light Communication using Color Clustered MIMO (컬러 클러스터 MIMO 기술을 적용한 해상 가시광 통신 시스템)

  • Kim, Hyeong-ji;Chung, Yeon-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.8
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    • pp.1773-1779
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    • 2015
  • Shore-to-sea visible light communication using color clustered multiple-input and multiple-output (MIMO) is presented. The proposed maritime visible light communication (MVLC) offers a low-cost, high-speed wireless link for shore-to-sea maritime communications. Each color cluster is comprised of 50 red, green and blue (RGB) light emitting diodes (LEDs) and is modulated using on-off-keying (OOK). Selection combining is performed at the receiver, producing diversity effect within that color cluster. In this paper, we employ sea states (wave height, wind speed, etc.) data from both Pierson-Moskowitz and JONSWAP spectrum models under atmospheric turbulence conditions. Based on the simulation model, the maritime link quality is analysed in terms of coverage distance and bit error rate performance. The results show that the proposed system provides an efficient MVLC, while satisfying International Association of Lighthouse Authorities (IALA) requirements for maritime buoyage system and also offering sufficient illumination from high power LEDs.

SIC-Aware Relay Transceiving Filter Design for Multiuser Two-way Relaying Systems (다중 사용자 양방향 릴레이 시스템을 위한 자가 간섭 소거 인지 릴레이 송수신 필터 설계)

  • Park, Jin-Bae;Wang, Jin-Soo;Kim, Yun-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.1A
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    • pp.64-72
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    • 2012
  • We consider multiuser multiple antenna two-way relaying systems in which all users exchange their data with their counterparts with the help of a relay. The systems complete all data exchanges in two time phases called multiple access phase and broadcasting phase for spectral efficiency and therby require an effective scheme reducing self-interference (SI) and multiuser interference (MUI). Different from the conventional scheme suppressing both SI and MUI at the relay, the proposed scheme adopts SI cancelation (SIC) at the users and renders the relay to suppress the MUI mainly considering the SIC output. We analyze the symbol error rate (SER) and the achievable diversity order of the proposed scheme when the multiple access phase is dominant in the performance and obtain simulation results on the SER and the sum rate under various conditions. The results show that the proposed scheme improves the symbol error rate and the sum rate remarkably at the cost of complexity increase.

A Study on Oriental Images of Modern Fashion in the New Paradigm (뉴 패러다임을 통해 나타난 현대 패션 동양적 이미지 연구)

  • Ko, Myung-Sin;Chae, Keum-Seok
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.5
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    • pp.704-716
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    • 2008
  • This study aims to explore the creation of fashion design that embraces the diversity of human culture by examining oriental images that appear in the modern fashion with a focus on new paradigms that significantly affect human life as the latest trends, and by reflecting the trends of the times. The results of this study are as follows: First, this study examined that with regard to paradigm, a theoretical frame to view universe, the dichotomous, determinist, mechanism, linear paradigm collapsed to convert to undetermined, exoteric, pluralistic, indeterministic, organic, and holistic paradigm. The new paradigm is identified to have emerged before and after 1950s, and through the new paradigm, the characteristics of postmodernism such as historicality, popularity, locality, folkways and the characteristics of deconstructionism, internally mutual text, post phenomenon, undeterminability and externally exposure, destruction, poverty, decomposition and analysis, were identified. Second, the Orient is defined as the generic term referring to the entire Asian areas east of Turkey. Through the developmental process of oriental images, it was converted from the Oriental image, which mysteriously and romantically represents oriental elements, into the ethnic image that represents long time oriental traditions and indigenous culture together with the characteristics of the new paradigm. Third, the artistic characteristics of the Oriental costumes presented by Korea, China and Japan are expressed in developmental types, T-type plane structure, layered style, asymmetrical adjustment and easy silhouette, and they show indigenous characteristics of each country, for example, Chinese styles in dragon pattern, red and yellow, Japanese styles in flower design and achromatic color. Fourth, the Oriental Image, combined with the postmodernism and deconstructionism through the new paradigm, has two: one Oriental image highlights traditional elements by creating new Oriental image such as natural image, folk image, hybrid image and deconstruction image; and another is undetermined and vague by combining or decomposing Oriental or Western elements. It is expected that fashion designs that reflect these contexts of the times will contribute to the strengthening of international competitiveness.

Flexural Vibration of Stiffened Plates in Contact with Water (보강판(補剛板)의 접수진동(接水振動))

  • K.C.,Kim;K.P.,Rhee;H.Y.,Lee
    • Bulletin of the Society of Naval Architects of Korea
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    • v.17 no.2
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    • pp.11-16
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    • 1980
  • For vibration analysis of stiffened plates the orthotropic plate analogy is commonly accepted. As to stiffened plates in contact with water, however, there is still much uncertainty in estimation of the added mass because of the lack of direct methods. The authors, considering that for added mass of plates there are many reliable data derived theoretically or experimentally available, suggest a method to estimate the added mass of a stiffened plate by combining the mass increase factor, $\beta$, of an equivalent orthotropic plate and the correction factor, $\kappa$, for the effects of stiffeners. The latter is to be derived from systematic experimental investigations. Then, the natural frequency in water, f', can be calculated from that in air, f, by the equation $f'=f/\sqrt{1+\kappa\beta}$. To investigate practical applicability of this method, a systematic experiment was carried out with five uniaxially stiffened plates. Each of them had a plate of same size, $600mm{\times}600mm{\times}3.2mm$, but stiffeners of different size in the web-depth, 41.6mm, 51.2mm or 66.8mm and of different spacing 75mm, 100mm, or 150mm. Natural frequencies were measured under simply supported-edge conditions in both air and water, and corresponding $\kappa$ values derived. In spite of wide variations of web-depth and spcae of stiffeners, the experimental results show that the diversity of $\kappa$ values is not remarkable; mean values of $\kappa$ are 1.31 with standard deviation of 0.025 for the first modes and 1.27 with that 0.077 for the second modes. Hence, the authors concluded that the above $\kappa$ values can be used generally for the cases of uniaxially stiffened plates both sides of which contact with water, and that $\kappa$ values of general use for the cases of cross-stiffened plates may also be obtainable from similar experiments.

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Performances of wireless ATM cell transmission with partial concatenated coding (무선 ATM셀 전송을 위한 부분 연쇄 부호화 기법의 성능분석)

  • 이진호;김태중;이동도;안재영;황금찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.2014-2026
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    • 1997
  • In this paper, the performances of wireless asynchronous transfer mode (ATM) cell transmission in mobile work are analyzed. We adopt 16Star QAM as amodulation technique in wireless channel and considered Reed-Solomon, convolutional, and concatenated coding to improve the error rate performances, and also proposed the Partial Concatenated Coding (PCC) technique as UEP(unequal error protection) code for efficient transmission of ATM cell in the air interface. We consider Doppler's effect, Rician fading, and diversity technique of maximal-ratio combining (MRC) for mobile channel model. For performance measure, we analyze bit error rate, ATM cell loss probability, ATM cell error probability, and network performances of ATM cell transmission delay and throughput. The numerical results show that the adoption of PCC is a prospective way for the evolution of future wireless ATM network on mobile environment.

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A Study on Using Gray Color Dyeing from Gallapple (오배자에 의한 회색계열 염색에 관한 연구)

  • Shin, Nam-Hee;Kim, Sung-Yeon;Cho, Kuyung-Rae
    • Fashion & Textile Research Journal
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    • v.7 no.5
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    • pp.547-552
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    • 2005
  • The study has objective in raising value of the gray color as a meaningful color suiting sentiments of modern people by expressing the gray color in various perspective utilizing natural dyes that is natural at the same time having aesthetic color tones. For example, the main ingredient used for coloring black and gray color is the pyrogallol tannin and the gray tone dye can be acquired by combining the tannin with iron. In order to find the suitable condition for processing tannin, UV-Vis part absorption spectrum of Gallapple pyrogallol tannin, dye ability based on temperature and time, reflection rate based on concentration, color changes based on acid treatment and alkali treatment, changes on surface based on concentration or metal mordant condition, and lightfastness were measured. Maximum absorption wavelength (${\lambda}_{max}$) of Gallapple tannin was at around 273 nm, while strong absorption was also observed at below 350 nm. Dye ability of Gallapple tannin is done more easily on silk rather than cellulose fibers such as cotton, while the optimum condition for dyeing was observed to be at $60^{\circ}C$, for 20 minutes. As a result of acid treatment, the color of dye material consist highly of gray tones and showed red tone after the alkali treatment. While it was observed that as dye concentration and metal mordant concentration increased the color changed at counter-clockwise direction on the Y-scale of Munsell's scale of colors. Lightfastness was more on a normal fading. I hope this study opens up possibilities towards presenting gray color expressed from tannin as color with diversity and aesthetic value. In future, comparative study between dye expressed from catechol tannin dye materials will be helpful.

Legal and Regulating Improvement for Distribution of Used Medical Equipments (중고 의료기기의 유통에 대한 법적 규제 개선)

  • Choi, Yong Jeon;Kwon, Jun Cheol;Jung, Yong Gyu
    • Journal of Service Research and Studies
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    • v.4 no.1
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    • pp.109-121
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    • 2014
  • Used medical equipment utilized in medical technology, most are not human or environmental risks likely to in normal medical technology. Therefore, the risk is close to zero so that medical devices are classified into Class 1 medical device, such as little or no risk by treating. It can be minimized without arising unnecessary and waste of time. As handlers in the medical device vendors are expanding the area of the business, we can uplift operators' commitment to the business and for the people's choice. In this paper, our research are presented to improve the legal and regulatory directions for the distribution of used medical devicesin in order to establish and promote a fair deal of diversity.

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