• Title/Summary/Keyword: Divided Channel

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Effect of Electroacupuncture at GB14 on Brain Activity (양백(GB14) 전침자극이 뇌파 변화에 미치는 영향)

  • Kang, Tae-Ri
    • Korean Journal of Acupuncture
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    • v.36 no.4
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    • pp.241-251
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    • 2019
  • Objectives : The purpose of this study was to examine the effects of electroacupuncture at GB14, on brain activity assessed on an electroencephalogram(EEG). Methods : (1) Thirty-four healthy participants were randomly divided into two groups, receiving either real acupuncture or non-penetrating sham acupuncture at GB14. (2) EEG measurements were conducted simultaneously before and after a 5-minute electroacupuncture stimulation, and the differences in the resulting EEG parameters were compared between the test and control groups. Results : (1) Absolute power increased significantly in the theta-wave channel of the occipital region and in the entire alpha-wave channel. (2) Relative power decreased significantly in the theta-wave channels of the frontal and occipital regions. (3) Coherence decreased significantly in the theta- and beta-wave channels of the parietal and occipital regions, and increased significantly in the alpha-wave channels of most areas. Conclusions : This study shows that electroacupuncture stimulation at GB14 activates the alpha frequency band in particular.

The Analysis of an Opportunistic Spectrum Access with a Strict T-preemptive Priority Discipline (엄격한 T-축출 우선순위 대기행렬을 이용한 기회 주파수 접근 방식의 성능 분석)

  • Kim, Kilhwan
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.4
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    • pp.162-170
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    • 2012
  • We propose a new priority discipline called the strict T-preemptive priority discipline, and derive the waiting time distributions of each class in the strict T-preemptive priority M/G/1 queue. Using this queueing analysis, we evaluate the performance of an opportunistic spectrum access in cognitive radio networks, where a communication channel is divided into time slots, a licensed primary user is assigned to one channel, and multiple unlicensed secondary users may opportunistically exploit time slots unused by the primary user. We also present a numerical example of the analysis of the opportunistic spectrum access where the arrival rates and service times distributions of each users are identical.

Research Trends on Physical Layers in Wireless Communications Using Machine Learning (무선 통신 물리 계층의 기계학습 활용 동향)

  • Choi, Y.H.;Kang, H.D.;Kim, D.Y.;Lee, J.H.;Park, Y.O.
    • Electronics and Telecommunications Trends
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    • v.33 no.2
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    • pp.39-47
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    • 2018
  • The fundamental problem of communication is that of transmitting a message from a source to a destination over a channel through the use of a transmitter and receiver. To derive a theoretically optimal solution, the transmitter and receiver can be divided into several processing blocks, with each component analyzed and optimized. The idea of machine learning (or deep learning) communications systems goes back to the original definition of the communi-cation problem, and optimizes the transmitter and receiver jointly. Although today's systems have been optimized over the last decades, and it seems difficult to compete with their performance, deep learning based communication is attractive owing to its simplicity and the fact that it can learn to communicate over any type of channel without the need for mathematical modeling or analysis.

Development of ZigBee Wireless Communication System for Remote Diagnosis in Distribution Power Lines (배전선로 원격 진단을 위한 ZigBee 무선통신 시스템 개발)

  • Lee, Kyeong-Seob;Chung, Dong-Hyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.28 no.9
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    • pp.602-606
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    • 2015
  • This paper presents a ZigBee wireless communication system for remote diagnosis in overhead distribution power lines. The system is divided in three parts in the functional aspect - a host computer module, a remote controller module and a diagnostic system module. The host computer module designed as USB interface transmits control signals and receive data measured by sensor. The remote controller module operates the diagnostic system. Diagnostic system module communicates with internal main controller and host computer USB. Multiple communication channel is adopted for simultaneous operations of several diagnostic system. Dedicated protocol for each module is developed. The system is designed with a focus on low cost and small size suitable for lightweight and small diagnostic system.

Segmentation by Benefit Sought in Marketing Channel : A Sequential Approach (추구혜택에 의한 유통시장의 시장세분화 : 순차적 접근)

  • Yi, Seong-Keun;Kim, Jae-Wook;Lee, Seo-Koo
    • Journal of Distribution Research
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    • v.10 no.3
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    • pp.87-101
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    • 2005
  • Market segmentation has been an important issue in marketing for a long time. Many models and statistical methods have been developed by many scholars. The purpose of this research provides one insight for market segmentation based on clustering technique in channel benefit sought. We proposed a sequential approach in market segmentation. A sequential approach means that we do market segmentation by multi-stage method based on the benefits sought in marketing channel. To achieve this approach, we divided the main benefits sought into subcategories. That is to say, after dividing each benefit sought into more detailed concepts, we did market segmentation sequentially.

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The Rearch of the Young-su(迎隨) (영수보사(迎隨補瀉) 연구(硏究))

  • Im, Jin-Seok
    • Journal of Korean Medical classics
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    • v.12 no.2
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    • pp.282-292
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    • 1999
  • In oriental medicine Acupuncture treatment is one of the most valuable therapy. Through the acupuncture humen have been healed many diseaes with his own natural therapic power, without medicine or surgery ect. But there have not formed a clear definition on the supplement & eradication(補瀉). I recognised the difference between the original meaning of Young-su(迎隨) mentioned in $\ll$Whang-Je-Nae-Kyung(黃帝內經)$\gg$ and Young-su-Bo-Sa(迎隨補瀉) that are recently used. The results were summerized as follow; 1. In the $\ll$Whang-Je-Nae-Gyung$\gg$, when they give medical teatment, they have totally used all methods of the supplement & eradication(補瀉). Therefore as now divided into respiration, speed, rotation and close-open supplement & eradication(補瀉) have many problomes. And Young-su(迎隨) did not mean the treatement of supplement and eradication which go with or against the flowing of channel energy(經氣). Young-su(迎隨) is not a simple technique of treatment, but is the totall principle of the supplement and eradication. 2. The direction of channel energy(經氣) connected with the O-su point (五輸穴) is from extremities to the trunk of body, therefore the direction of supplement is to the trunk of body and the direction of eradication is to extermities. 3. In the case of using the treatment which go with or against the flowing of channel energy(經氣), in oder to avoid the confusion of term, it must be defined another term. 4. It is necessary that we must define the procedure of supplement & eradication, and the objective indication that ascertain whether the doctor's purposes are really obtained.

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Three Dimensional FEM Simulation for Spinning of Non-circular Fibers

  • Kim, Heejae;Chung, Kwansoo;Youn, Jae-Ryoun
    • Fibers and Polymers
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    • v.1 no.1
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    • pp.37-44
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    • 2000
  • A finite element method is employed fer a flow analysis of the melt spinning process of a non-circular fiber, a PET(polyethylene terephthalate) filament. The flow field is divided into two regions of die channel and spin-line. A two dimensional analysis is used for the flow within the die channel and a three dimensional analysis fur the flow along the spin-line. The Newtonian fluid is assumed for the PET melt and material properties are considered to be constant except for the viscosity. Effects of gravitation, air drag force, and surface tension are neglected. Although the spin-line length is 4.5 m only five millimeters from the spinneret are evaluated as the domain of the analysis. Isothermal and non-isothermal cases are studied fer the flow within the die channel. The relationship between the mass flow rate and the pressure gradient is presented for the two cases. Three dimensional flow along the spin-line is obtained by assuming isothermal conditions. It is shown that changes in velocity and cross-sectional shape occur mostly in the region of 1mm from the die exit.

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Finite element analysis of the fluid-structure interaction in a compliant vessel (유연 혈관에서 유체-고체 상호작용에 대한 유한요소 해석)

  • Shim, Eun-Bo;Ko, Hyung-Jong;Kamm, Roger D.
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.591-596
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    • 2000
  • Flow through compliant tubes with linear taper in wall thickness is numerically simulated by finite element analysis. Two models are examined: a planar two-dimensional channel, and an axisymmetric tube. For verification of the numerical method, flow through a compliant stenotic vessel is simulated and compared to existing experimental data. Computational results for an axisymmetric tube show that as cross-sectional area falls with a reduction in downstream pressure, flow rate increases and reaches a maximum when the speed index (mean velocity divided by wave speed) is near unity at the point of minimum cross-section area, indicative of wave speed flow limitation or "choking" (flow speed equals wave speed) in previous one-dimensional studies. For further reductions in downstream pressure, flow rate decreases. Cross-sectional narrowing is significant but localized. When the ratio of downstream-to-upstream wall thickness is ${\le}$ 2 the area throat is located near the downstream end; as wall taper is increased to ${\ge}$ 3 the constriction moves to the upstream end of the tube. In the planar two-dimensional channel, area reduction and flow limitation are also observed when outlet pressure is decreased. In contrast to the axisymmetric case, however, the elastic wall in the two-dimensional channel forms a smooth concave surface with the area throat located near the mid-point of the elastic wall. Though flow rate reaches a maximum and then falls, the flow does not appear to be choked.

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A Benthic Polychaete Assemblage off the Korean South Coast(Gwangyang Bay and Yeosu Sound)

  • Kim, Yong-Hyun;Shin, Hyun-Chool
    • Fisheries and Aquatic Sciences
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    • v.13 no.2
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    • pp.157-166
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    • 2010
  • We investigated the benthic polychaete assemblage in Gwangyang Bay and Yeosu Sound in February 1997. The sediment was an almost entirely muddy facies. The benthic macrofauna comprised 295 species occurring at a mean density of 875 $indiv./m^2$. Polychaetes were the major faunal component; there were 94 species at mean density 765 $indiv./m^2$. The highest abundance and species richness occurred in the Myodo south and north channels, in the mouth of Gwangyang Bay, and in the Noryang channel mouth. The most abundant polychaete was Tharyx sp. (47.9%), followed in rank order by Heteromastus filiformis (9.6%), Melinna cristata (9.3%), and Lumbrineris longifolia (7.3%). Cluster analysis divided the study area into four station groups based on station similarities in benthic polychaete assemblages: the Glycinde-Prionospio cluster in the western inner bay, the H. filiformis cluster in the middle inner bay, the Melinna-Lumbrineris cluster in the Myodo south-north channel, and the Tharyx cluster in the eastern main channel region. The sediment type of Gwangyang Bay has changed gradually from sandy to muddy. Dominant species have also changed from Chone teres and Lagis bocki to Tharyx sp., which is a potential organic pollution indicator.

STRATIGRAPHIC ARCHITECTURE OF FLUVIAL SEQUENCES IN THE NORTHWESTERN PART OF KYONGSANG BASIN

  • Jo H. R.;Chough S. K.
    • 한국석유지질학회:학술대회논문집
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    • autumn
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    • pp.47-56
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    • 2000
  • The northwestern part of Kyongsang Basin largely comprises interbedded sandstone and mudstone with local conglomeratic deposits in the basin margin, representing marginal alluvial fans and fluvial depositional environments. The non-marine successions are divided into successive stratigraphic units, each of which is unique in facies assemblages and architecture of sandstone bodies. Two stratigraphic units, i.e., Sinpyong-Anpyong and Jotap units are examined in terms of stratigraphic architecture and its causative processes. Detailed architectural analysis reveals that the channel systems of Sinpyong-Anyong unit were of braided patterns, whereas those of Jotap unit were dominated by small-scale bedforms. The difference in fluvial styles can be attributed to the changes in amount and caliber of sediment load and water discharge, which might have been ultimately governed by basin tectonics, climate, and base level. Along with the marked change in fluvial style, the two successive units show repeated expansions of distal, water-logged floodplains and lacustrine facies in the basal and uppermost parts of Sinpyong-Anpyong unit, where the proportion of channel sandstone bodies is relatively low. These stratigraphic intervals are succeeded by the sequences with proximal, well-drained floodplain facies and relatively coarser-grained channel sandstone bodies of higher proportion, reflecting the progradation of proximal systems (the middle part of Sinpyong-Anpyong unit and Jotap unit). The overall stratigraphic architecture can be ascribed to the fluctuations in accommodation space and sediment supply induced by repeated basin subsidence.

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