• Title/Summary/Keyword: 지연 공간

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The Enhancement of the Acoustic Image by Combining Bases of Support for SFR (Spatial Frequency Response) (공간주파수응답의 기저대역 확장에 의한 초음파영상의 개선)

  • Song, Dae-Geon;Oh, Tong-In;Kim, Hyun;Jun, Kye-Suk
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.5
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    • pp.408-417
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    • 2003
  • In this paper, we have studied the enhancement of the acoustic image by combining bases of support for SFR (Spatial Frequency Response) taken at multi-frequencies. The scanning acoustic microscope system have been constructed using the quadrature detector that is able to measure the amplitude and phase of the reflected signal simultaneously. Both real and quadrature components of reflected signal have been acquired at 4.4 ㎒ to 5.6 ㎒ reliably and accurately. In this experimental result, better depth resolution can be obtained by numerically combining images taken at several different frequencies. Image intensity have been better about 3.4 times at multi-frequency than one at a single frequency.

A Study on the Group Routing Algorithm in DHT-based Peer-to-Peer System (DHT 기반 P2P 시스템을 위한 그룹 라우팅 알고리즘에 관한 연구)

  • Park, Yong-Min
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.12
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    • pp.111-120
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    • 2012
  • As the P2P System is a distributed system that shares resources of nodes that participate in the system, all the nodes serve as a role of server and client. Currently, although systematic, structured P2P systems such as Chord, Pastry, and Tapestry were suggested based on the distributed hash table, these systems are limited to $log_2N$ for performance efficiency. For this enhanced performance efficiency limited, the article herein suggests group routing algorithm. The suggested algorithm is a node-to-group routing algorithm which divides circular address space into groups and uses a concept of pointer representing each group, which is an algorithm where routing is performed based on pointer. To evaluate algorithm performance, a comparative analysis was conducted on average hops, routing table size, and delayed transmission for chord and routing, a signature algorithm in P2P systems. Therefore, enhanced performance is verified for comparative items from the simulation results.

Design of MSB-First Digit-Serial Multiplier for Finite Fields GF(2″) (유한 필드 $GF(2^m)$상에서의 MSB 우선 디지트 시리얼 곱셈기 설계)

  • 김창훈;한상덕;홍춘표
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.6C
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    • pp.625-631
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    • 2002
  • This paper presents a MSB-first digit-serial systolic array for computing modular multiplication of A(x)B(x) mod G(x) in finite fields $GF(2^m)$. From the MSB-first multiplication algorithm in $GF(2^m)$, we obtain a new data dependence graph and design an efficient digit-serial systolic multiplier. For circuit synthesis, we obtain VHDL code for multiplier, If input data come in continuously, the implemented multiplier can produce multiplication results at a rate of one every [m/L] clock cycles, where L is the selected digit size. The analysis results show that the proposed architecture leads to a reduction of computational delay time and it has much more simple structure than existing digit-serial systolic multiplier. Furthermore, since the propose architecture has the features of unidirectional data flow and regularity, it shows good extension characteristics with respect to m and L.

A Scalable Content-Sharing Architecture for High-quality TV Programs (확장 가능한 실시간 고화질 TV 컨텐츠 공유 아키텍처)

  • Chung, Sungwook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2651-2657
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    • 2014
  • It can be organized with PVRs and FC-AL for a high-quality TV content-sharing architecture. It is, however, not easy to configure a large community network with the FC-AL since it has a 7-bit address space with supporting up to 127 users. We, therefore, propose a novel scalable FC-AL multiple-loop architecture using shared disks, which does not need to use expensive and load-concentrated switches. In this article, our suggested architecture shows a superb startup delay, such as less than 20msec. In addition, it demonstrates outstanding scalability, such that the number of accomodable users increases almost linearly according to adding loops. Lastly, it reveals exceptional time-shifting hours, that is, which supports more than 140 hours with 1000 users.

Design and Evaluation of Fast-Handover Mechanism Between Hetrogeneous Networks Considering the Location Management in PMIPv6 (PMIPv6에서의 위치관리기법을 고려한 이 기종 망간의 Fast Handover 기법 설계 및 평가)

  • Shim, JaeSung;Park, SeokCheon
    • KIPS Transactions on Computer and Communication Systems
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    • v.1 no.3
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    • pp.219-228
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    • 2012
  • As the wireless Internet become more widely accessible, variety of Internet services can be used without limitation of location. However, existing mobility management methods such as MIP and PMIP of IETF requires the load of heavy protocol stack on the mobile nodes or the addition of components such as LMA and MAG. In this paper, we proposed the location management technique in the PMIPv6 and Fast Handover technique. according to the moving pattern of the node, the location management technique proposed in order to adjust the paging area dynamically. The Fast Handover technique applied MIH technology and it reduced the handover signal processing time between heterogeneous network. The location management cost in the environment which the node moves in order to evaluate this and handover delay time was calculate. The proposal technique was efficiently more evaluated than PMIPv6 with the smallest 29% and maximum 83%.

A Study on the Principle of F.O.A Construction Space Creation Viewed from the Discussion of Otherness (타자성의 담론으로 본 F.O.A 건축 공간생성 원리에 관한 연구)

  • Lee, Ji-Yeon
    • Korean Institute of Interior Design Journal
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    • v.17 no.3
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    • pp.86-93
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    • 2008
  • The purpose of this study is to find out how the otherness philosophy reveals itself in the principle of F.O.A construction space creation. The traditional philosophy of totality is self-centered and thoughts are based on the subject. It couldn't escape from the world associated with the self, and has subordinated the other to the main body. But the philosophy of otherness transcends the subject, to the open, creative way of thinking which acknowledges deconstruction, decentralization, and non-hierarchy. This is very similar to contemporary architecture, which pursuits change, and also to the current state of society. In construction by the construction group F.O.A, which is doing notable activity this generation, there is an attempt to transcend the fixed subject which is seen in the otherness discussion, and realize recategorization by overcoming the boundaries of subject and object. First, by the realization of landscape architecture using a topographical folding technique, boundaries of the subject and object are demolished in the relationship of the landscape construction, and recategorization. Second, by breaking up the meaning of the surface which is a visual and physical boundary for both the internal and external, recategorization is being done. Third, by making the boundary between the interior and exterior indistinct, cognitive threshold is dissolved, and the relationship between the subject and object is being recategorization. In conclusion, we can see that the many recategorization phenomenons that are happening in the F.O.A construction show the otherness that escapes from the conventional and stationary relationship, and recognizes each other at the same time, forming new relationships.

A Case Study of Minimizing Construction Time in Long and Large Twin Tube Tunnel (대단면 장대터널 공기단축 사례연구)

  • No Sang-Lim;Noh Seung-Hwan;Lee Sang-Pil;Kim Moon-Ho;Seo Jung-Woo
    • Tunnel and Underground Space
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    • v.15 no.3 s.56
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    • pp.177-184
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    • 2005
  • The Sapaesan tunnel, the longest twin tube tunnel (4km) in Korea with 4 lanes each, is under construction with two years of delayed schedule because of the strong opposition from environmental bodies. Therefore, maximizing the construction efficiency was needed in tunnel project to compensate for time delay. This study includes improvements in the construction of the Sapaesan tunnel such as increasing excavation length and changing excavation sequence. In this paper the system for predicting tunnel face ahead is also introduced. Bulk-Emulsion explosive and Cylinder-Cut method were adopted in tunnel blasting to increase the excavation length. Optimum tunnel excavation step was designed to make up delayed time. Tunnel foe mapping, TSP survey and geological prediction system using computerized jumbo-drill were performed fnr safe construction of long and large twin tube tunnel.

A Study on the relationship of between meteo-hydrological characteristics and malaria - case of korea - (수문 기상학적 환경특성과 말라리아 발생간의 상관관계에 관한 연구 -한반도를 사례로-)

  • Choi, Don-Jeong;Park, Kyung-Won;Suh, Yong-Cheol
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.457-457
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    • 2012
  • 말라리아는 매개체에 의한 전염병으로써 국내에서는 이미 1970년대에 사라진 것으로 알려져 있다. 하지만 1990년대에 재발생하여 2000년대 초반까지 경기도와 강원도 북부지역에서 환자가 증가하는 양상을 보였다. 사람에게서 발병하는 말라리아는 4종으로 알려져 있으나 우리나라의 경우 이 중 오로지 삼일열 원충감염에 의한 것으로 밝혀졌다(질병관리 본부, 2010). 기후변화는 질병의 발생에 영향을 미칠 수 있는 중요한 요인 중 하나로써 매개체에 의한 질병의 경우 기후요소는 매개체의 번식과 활동에 적지않은 영향을 미친다. 특히 말라리아의 경우 병원균을 가진 개체수와 모기에 물리는 횟수, 감염된 모기의 수, 그 모기에 사람이 물리는 횟수와 관계가 있으나 기온과 강수량, 습도의 변화 등 기후 및 수문학적 요소와도 밀접한 관계를 가지는 것으로 밝혀졌다(Lindsay & Birley, 1996; 박윤형 외, 2006; 신호성, 2011 재인용). 본 연구의 목적은 한반도 기후-수문학적 환경특성 및 변화를 파악하고 지역적 말라리아 발생과의 상관관계를 도출하며 이를 기반으로 하여 말라리아 발생의 변동을 예측하는 것이다. 분석에 사용된 데이터는 말라리아 발생자료의 경우, 질병관리 본부에서 제공하는 2001년 1월~2011년 12월 까지의 약 16000건의 발병자료가 포함 되었고 분석의 시간 단위는 2WEEKS 이며 전국 251개의 시군구에서 발생한 전염병을 합산하였다. 기상자료의 경우 기상청 기후자료 관리 시스템에서 제공하는 동일 기간대의 평균기온, 최고(최저)기온, 강수량, 신적설, 평균 해면기압, 평균 이슬점 온도, 평균 상대습도, 평균풍속, 평균운량, 일조시간 자료를 활용하였다. 본 연구에 사용된 AWS(Automatic Weather Station)자료의 경우 기본적으로 point 형태의 관측자료이고, 분석기간 동안의 개수에서도 차이가 있기 때문에 공간 내삽기법인 kriging을 활용하여 행정구역과 zonal하는 방법으로 재가공 하였다. 지역의 수문학적 특성의 경우 10*10 DEM을 기반으로 ESRI ArcGIS 소프트웨어의 ArcHydro 기능을 이용 하여 유역을 생성하는 방법을 채택하였다. 본 연구에서는 통계적 모형을 기본으로 기후 및 수문 특성과 말라리아 발생간의 상관관계를 분석하였으며 시계열 자료의 특성상 포아송 분포의 Generalized Estimation Equation 과 Generalized Linear Model을 이용한다(Baccini 외, 2008; 신호성, 2011). 또한 말라리아 잠복시간의 지연효과 및 전염병의 계절 영향을 반영하기 위하여 Fourier transform 을 적용 하였다.

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Quantitative Method to Measure Thermal Conductivity of One-Dimensional Nanostructures Based on Scanning Thermal Wave Microscopy (주사탐침열파현미경을 이용한 1 차원 나노구조체의 정량적 열전도도 계측기법)

  • Park, Kyung Bae;Chung, Jae Hun;Hwang, Gwang Seok;Jung, Eui Han;Kwon, Oh Myoung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.12
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    • pp.957-962
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    • 2014
  • We present a method to quantitatively measure the thermal conductivity of one-dimensional nanostructures by utilizing scanning thermal wave microscopy (STWM) at a nanoscale spatial resolution. In this paper, we explain the principle for measuring the thermal diffusivity of one-dimensional nanostructures using STWM and the theoretical analysis procedure for quantifying the thermal diffusivity. The SWTM measurement method obtains the thermal conductivity by measuring the thermal diffusivity, which has only a phase lag relative to the distance corresponding to the transferred thermal wave. It is not affected by the thermal contact resistances between the heat source and nanostructure and between the nanostructure and probe. Thus, the heat flux applied to the nanostructure is accurately obtained. The proposed method provides a very simple and quantitative measurement relative to conventional measurement techniques.

Integration of Application Program for Dementia Diagnosis using Biometric Sensor and Oxygen Chamber (치매의 진단, 예방 및 완화를 위한 스마트폰용 게임 애플리케이션 개발)

  • Yun, Seong-Min;Choi, Hyo Sun;Cho, Myeon-Gyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.5
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    • pp.2953-2961
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    • 2014
  • Dementia once occurred is known to be mostly irreversible but can be treated only if it is detected early; especially vascular Dementia. Thus, in this paper we have developed Dementia diagnosis and care application through inter-working between biometric sensors and smart phone. With developing serious game for the demented elderly, we proposed ons-stop solution for Dementia; smart-phone application with diagnosis, prevention and mitigation of Dementia. Since the proposed game for mitigating Dementia requires sense of space and balance using both arms instead of operating simple arrow button, a treatment effect for Dementia will be doubled. If we tried to forestall, ease and cure Dementia with the proposed application. the social losses from Dementia would be minimized as a result.