• 제목/요약/키워드: FSO

검색결과 63건 처리시간 0.019초

러시아 연방법령 고찰을 통한 경호총국 소개 (Introduction of the FSO Through the Examination of Russia's Federal Law)

  • 김창호;오재환;박준호
    • 한국콘텐츠학회논문지
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    • 제10권10호
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    • pp.286-293
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    • 2010
  • 러시아 경호총국은 2004년 8월 7일 러시아연방 대통령령 No. 1013에 의해 해당 조직의 편성 및 지위를 체계적으로 구성하였다. 또한 경호총국 산하 특수통신 및 정보국의 창설과 경호총국 아카데미 신설을 통해 조직의 정보력과 교육훈련의 강화하고 있다. 또한 2005년 말 경호총국 역사상 처음으로 인터넷 홈페이지를 구축한 점과 최근 들어 잦은 언론자료 배포로 어둠속에 숨겨진 비밀조직에서 국가운영의 한 축을 담당하는 기관으로서 자신을 드러내고자 노력하고 있다. 이의 일환으로 러시아 경호총국은 2004년과 2005년에 대한민국 경호처와 대표단 교환을 통해 상호 이해의 폭을 넓히고자 노력하고 있다. 따라서 본 글에서는 전 세계적 변화에 대응하고자 노력하는 러시아 경호총국의 역사와 그 구조, 법적지위 등을 관련 법령을 중심으로 살펴보고, 나아가 이러한 모델이 우리나라의 공경호의 발전을 위해 적용가능한가를 살펴보도록 하겠다.

패션 쇼핑성향이 모바일 구매의도에 미치는 영향 - 성별/구매빈도에 따른 차이 - (The effect of fashion shopping orientation on consumer's purchase intention in a mobile shopping mall - The differences of groups according to gender and purchase frequency -)

  • 채진미
    • 복식문화연구
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    • 제24권4호
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    • pp.457-470
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    • 2016
  • The purposes of this study were to: 1) identify sub-factors of fashion shopping orientation (FSO) in adults aged 20 through 39, and analyze the differences among those FSO factors according to classified groups, which were based on gender and purchase frequency in a mobile shopping mall, and 2) to investigate the effects of FSO factors on mobile purchase intention according to the same classified groups. The questionnaire was conducted from November 10, 2015 to November 20, 2015 and its 432 respondents were classified into four groups, which were male/heavy purchaser, male/light purchaser, female/heavy purchaser, and female/light purchaser. The results of this study were as follows: First, fashion shopping orientation consisted of five sub-factors, which included "conspicuous brand pursuit", "economic pursuit", "pleasure/trend pursuit", "impulse shopping", and "convenience pursuit". Second, There were significant differences in three factors of FSO between male purchasers and female purchasers. Male purchasers showed higher tendency than female purchasers in "conspicuous brand pursuit", while female purchasers showed higher tendency than male purchasers in "economic pursuit" and "convenience pursuit". All the factors of FSO showed significant differences among the classified groups. Third, "economic pursuit", "pleasure/trend pursuit" and "convenience pursuit" affected mobile purchase intention in the case of male purchasers while "economic pursuit" and "conspicuous brand pursuit" had a influence on mobile purchase intention in the case of female purchasers. Fourth, the factors of FSO affected mobile purchase intention partly in each group. In conclusion. "economic pursuit" was proven to be the main influential factor to induce consumers to have a mobile purchase intention.

반 잠수식 복수부선의 진수설계 (Development of float off Operation Design for Mdlti Semi-submersible Barges with Symmetrical Stability Casings)

  • 양영태;최문길;이춘보;박병남;성석부
    • 한국해양공학회지
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    • 제17권2호
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    • pp.72-76
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    • 2003
  • This paper presents the design concept and operation results of float-off for FSO (340,000 DWT Class, ELF AMENAM KPONO Project) built on the ground, without dry dock facilities. It was the first attempt to build FSO, completely, on the ground and launch it using DBU (Double Barge Unit, which was connected by rigid frame structure.) The major characteristics of FSO, which are similar to general VLCC type hull, including topside structure, weigh 51,000 metric ton. In order to have sufficient stability during the deck immersion of DBU, while passing through a minimum water plane area zone, proper trim control was completed with LMC (Load Master Computer). The major features of the monitoring system include calculation for transverse bending moment, shear force, local strength check of each connector, based on component stress, and deformation check during the load-out and float-off. Another major concern during the operation was to avoid damages at the bottom and sides of FSO, due to motion & movement after free-floating; therefore, adequate clearances between DBU and FSO were to be provided, and guide posts were installed to prevent side damage of the DBU casings. This paper also presents various measures that indecate the connector bending moment, damage stability analysis, and mooring of DBU during float off.

BER Analysis of Coherent Free Space Optical Communication Systems with Holographic Modal Wavefront Sensor

  • Liu, Wei;Yao, Kainan;Huang, Danian;Cao, Jingtai;Wang, Liang;Gu, Haijun
    • Current Optics and Photonics
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    • 제1권1호
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    • pp.1-6
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    • 2017
  • Degradation of bit-error-rate (BER), caused by atmospheric turbulence, seriously hinders the performance of coherent Free Space Optical (FSO) communication systems. An adaptive optics system proves to be effective in suppressing the atmospheric turbulence. The holographic modal wavefront sensor (HMWFS) proposed in our previous work, noted for its fast detecting rates and insensitivity to beam scintillation, is applied to the coherent FSO communication systems. In this paper, based on our previous work, we first introduce the principle of the HMWFS in brief and give the BER of the coherent FSO with homodyne detection in theory, and then analyze the improvement of BER for a coherent FSO system based on our previous simulation works. The results show that the wavefront sensor we propose is better for weak atmospheric turbulence. The most obvious advantages of HMWFS are fast detecting rates and insensitivity to beam scintillation.

On the Performance of All-optical Amplify-and-forward Relaying with a Backup Radio-frequency Link Over Strong Atmospheric Turbulence and Misalignment Fading

  • Altubaishi, Essam Saleh
    • Current Optics and Photonics
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    • 제5권2호
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    • pp.114-120
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    • 2021
  • Free-space optical (FSO) communication is considered to be a potential solution to congestion in the radio-frequency spectrum and last-mile-access bottleneck issues in future cellular communication networks, such as 5G and beyond. However, FSO link performance may degrade significantly due to irradiance fluctuations and random temporal fluctuations from atmospheric turbulence. Therefore, in this work the main objective is to reduce the effect of the atmospheric turbulence by considering a multihop FSO communication system with amplify-and-forward relaying supported by a radio-frequency (RF) link, which form a hybrid FSO/RF communication system. The FSO link is assumed to follow the gamma-gamma fading model, which represents strong turbulence. Also, the RF link is modeled by a Rayleigh distribution. The performance of the considered system, in terms of the outage probability and average bit-error rate (BER), is investigated and analyzed under various weather conditions and pointing errors. Furthermore, the effect of the number of employed relay nodes on the performance of the system is investigated. The results indicate that the considered system reduces outage probability and average BER significantly, especially for low channel quality. Finally, the closed-form expressions derived in this work are compared to the results of Monte Carlo simulations, for verification.

Impact of Temporary Link Blockage on Ergodic Capacity of FSO System

  • Petkovic, Milica I.;Djordjevic, Goran T.
    • ETRI Journal
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    • 제40권3호
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    • pp.330-336
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    • 2018
  • Free-space optical (FSO) systems have attracted much attention from both research and application perspectives owing to their many benefits, such as license-free operation, low-cost, and high data rates. This paper investigates the ergodic capacity of FSO systems, which is an important metric of system performance. The stochastic temporary laser-beam blockage, pointing errors, and atmospheric turbulence are simultaneously considered. The results illustrate that the link blockage causes a decreased ergodic capacity. We show that to maximize the ergodic capacity, there is an optimal value of the laser-beam radius at the waist, which largely depends on pointing errors; however, it is independent of the atmospheric turbulence and the probability of link blockage.

LOADOUT DEVELOPMENT BY F.E. ANALYSIS METHODOLOGY FOR SIMILAR 300K VLCC SIZE FSO

  • 양영태;강희석
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2002년도 추계학술대회 논문집
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    • pp.51-55
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    • 2002
  • End of July. 2002 Hyundai Heavy Industries Co. Ltd. Offshore Division is successfully completed Load-out & Float-off work of "AMENAM KPONO/FSO Project" similar to 300K VLCC size. The AMENAM FSO hull and topside module built at the HHI Offshore yard using "On-Ground Building Method" developed by HHI. Various methodologies/techniques like Flexi-built FPSO Hull. Topside module erection method. Load-out Float-off methodology etc. are combined to develop a successful on-ground building method. In this paper, we described the "Hull Structural Strength Analysis Methodology" using 3-D Finite Element Analysis and results. This analysis is performed to verily the structural integrity or the AMENAM FSO hull during the main load-out on two semi-submersible barges combined together.

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Effect of fermented sarco oyster extract on age induced sarcopenia muscle repair by modulating regulatory T cells

  • Kyung-A Byun;Seyeon Oh;Sosorburam Batsukh;Kyoung-Min Rheu;Bae-Jin Lee;Kuk Hui Son;Kyunghee Byun
    • Fisheries and Aquatic Sciences
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    • 제26권6호
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    • pp.406-422
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    • 2023
  • Sarcopenia is an age-related, progressive skeletal muscle disorder involving the loss of muscle mass and strength. Previous studies have shown that γ-aminobutyric acid (GABA) from fermented oysters aids in regulatory T cells (Tregs) cell expansion and function by enhancing autophagy, and concomitantly mediate muscle regeneration by modulating muscle inflammation and satellite cell function. The fermentation process of oysters not only increases the GABA content but also enhances the content of branched amino acids and free amino acids that aid the level of protein absorption and muscle strength, mass, and repair. In this study, the effect of GABA-enriched fermented sarco oyster extract (FSO) on reduced muscle mass and functions via Treg modulation and enhanced autophagy in aged mice was investigated. Results showed that FSO enhanced the expression of autophagy markers (autophagy-related gene 5 [ATG5] and GABA receptor-associated protein [GABARAP]), forkhead box protein 3 (FoxP3) expression, and levels of anti-inflammatory cytokines (interleukin [IL]-10 and transforming growth factor [TGF]-β) secreted by Tregs while reducing pro-inflammatory cytokine levels (IL-17A and interferon [IFN]-γ). Furthermore, FSO increased the expression of IL-33 and its receptor IL-1 receptor-like 1 (ST2); well-known signaling pathways that increase amphiregulin (Areg) secretion and expression of myogenesis markers (myogenic factor 5, myoblast determination protein 1, and myogenin). Muscle mass and function were also enhanced via FSO. Overall, the current study suggests that FSO increased autophagy, which enhanced Treg accumulation and function, decreased muscle inflammation, and increased satellite cell function for muscle regeneration and therefore could decrease the loss of muscle mass and function with aging.

Asymptotic Performance Analysis of Free-Space Optical Links with Transmit Diversity

  • Feng, Jianfeng;Zhao, Xiaohui
    • Journal of the Optical Society of Korea
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    • 제20권4호
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    • pp.451-463
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    • 2016
  • The misalignment errors and fluctuations in irradiance due to atmospheric turbulence can severely degrade the performance of free-space optical (FSO) systems. In this paper, we investigate the asymptotic bit error rate (BER) performance and diversity orders of FSO links using parallel transmit-diversity schemes. The BER expressions of FSO links with the switch-and-examine transmit (SET), switch-and-examine transmit with post-selection (SETps), dual-branch transmit laser selection (Dual-TLS), and group transmit laser selection (Group-TLS) schemes are derived, based on an approximate channel model. Then numerical simulations for these four schemes in the region of high average signal-to-noise ratio (SNR) are presented under different channel conditions. The results show that the four transmit-diversity schemes can reduce system complexity and overcome the limitation of peak power, without much BER deterioration.

Hybrid Atmospheric Compensation in Free-Space Optical Communication

  • Wang, Tingting;Zhao, Xiaohui
    • Journal of the Optical Society of Korea
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    • 제20권1호
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    • pp.13-21
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    • 2016
  • Since the direct-gradient (DG) method uses the Shack-Hartmann wave front sensor (SH-WFS), based on the phase-conjugation principle, for atmospheric compensation in free-space optical (FSO) communication, it cannot effectively correct high-order aberrations. While the stochastic parallel gradient descent (SPGD) can compensate the distorted wave front, it requires more calculations, which is sometimes undesirable for an FSO system. A hybrid compensation (HC) method is proposed by properly using the DG method and SPGD algorithm to improve the performance of FSO communication. Simulations show that this method can well compensate wave-front aberrations and upgrade the coupling efficiency with few computations, preferable correction results, and rapid convergence rate.