• Title/Summary/Keyword: DMO

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Algorithm of Channel Selection for DMO Communication in TETRA System (TETRA 시스템에서 DMO 통신을 위한 채널 선택 알고리즘)

  • Lee, Soon-Hwa;Kim, Chang-Bock
    • Journal of Advanced Navigation Technology
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    • v.17 no.5
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    • pp.497-505
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    • 2013
  • In TETRA(TErrestrial Trunked RAdio) standard, TMO(Trunked Mode Operation) communicates with the UE through the base station and it has a higher priority than DMO(Direct Mode Operation) which communicates with UE directly for channel allocation. As a result, the UE needs an algorithm which restricts the frequency allocation by TMO so that DMO can have a successful communication within the network. However, the TETRA DMO standard does not consider this issue. In this paper, we propose an active DMO channel selection algorithm which allocates a channel based on some additional information such as channel usage state of TMO and channel utilization of DMO. The experimental results show that the proposed algorithm outperforms existing DMO channel allocation scheme in terms of the transmission efficiency.

Radio Coverage Prediction of DMO Terminal in TETRA TRS (TETRA TRS에서 DMO 단말기의 전파도달범위 예측)

  • Lee, Soon-Hwa;Kim, Chang-Bock
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.51-56
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    • 2014
  • TETRA(TErrestrial Trunked RAdio) provide specialized disaster radio communication services as a standard European for digital TRS(Trunked Radio System). Especially, DMO(Direct Mode Operation) feature is used effectively in the radio shadow areas which base station does not propagate radio signal because it can communicate directly with terminal to terminal without base station's relay function. However, to effectively used DMO feature, radio coverage prediction information should be provided to users. Therefore in this paper, we were calculated link budget of TETRA DMO terminals which were distributing and operating in the country and then predicted reaching distance about radio propagation to be applied with path loss model.

A Study on Dip-Moveout of Seismic Reflection Data (탄성파반자료자료의 경사보정 연구)

  • 양승진
    • Economic and Environmental Geology
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    • v.32 no.5
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    • pp.495-502
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    • 1999
  • Common-mid-point (CMP) seismic data on a dipping layer have have a stacking different from a horizontal layer velocity and the reflection points on data are dispersed to many positions. Therefore, the CMP data are not stacked well by the conventional stacking method using the horizontal layer velocity. The CMP gather can ideally stacked by applying dip-moveout(DMO) processing. Hence, modern seismic processing indludes DMO as an essential routine step. DMO processing techniques are broadly categorized by two, Fourier transform and integral methods, each of which has many different computational schemes. In this study, the dip-decomposition technique of the Fourier transform method is used to test the DMO effect on the synthetic scismic data generated for dipping structures. Each of constnat offset sections NMO corrected by using the layer velocity of the model and DMO processed. The resulting zero-offset sections for many offsets are stacked. The stacked sections with DMO processing show the structural boundaries of the models much better than those without DMO processing.

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Teaching the Derivation of Area Formulas for Polygonal Regions through Dissection-Motion-Operations (DMO): A Visual Reasoning Approach

  • Rahim, Medhat H.
    • Research in Mathematical Education
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    • v.14 no.3
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    • pp.195-209
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    • 2010
  • Utilizing a structure of operations known as Dissection-Motion-Operations (DMO), a set of mathematics propositions or area-formulas in school mathematics will be introduced through shape-to-shape transforms. The underlying theme for DMO is problem-solving through visual reasoning and proving manipulatively or electronically vs. rote learning and memorization. Visual reasoning is the focus here where two operations that constitute DMO are utilized. One operation is known as Dissection (or Decomposition) operation that operates on a given region in 2D or 3D and dissects it into a number of subregions. The second operation is known as Motion (or Composition) operation applied on the resultant sub-regions to form a distinct area (or volume)-equivalent region. In 2D for example, DMO can transform a given polygon into a variety of new and distinct polygons each of which is area-equivalent to the original polygon (cf [Rahim, M. H. & Sawada, D. (1986). Revitalizing school geometry through Dissection-Motion Operations. Sch. Sci. Math. 86(3), 235-246] and [Rahim, M. H. & Sawada, D. (1990). The duality of qualitative and quantitative knowing in school geometry, International Journal of Mathematical Education in Science and Technology 21(2), 303-308]).

Chemical Factors on the Homogeneous Precipitation of Barium Titanyl Oxalate by Dimethyl Oxalate and Their Effects on the Charateristics of Barium Titanate (Dimethyl oxalate에 의한 barium titanyl oxalate의 균일 침전에 미치는 화학적 인자와 이들이 티탄산 바륨의 특성에 미치는 영향)

  • Ryu, Kyoungyoul;Huh, Wooyoung;Lee, Chul
    • Analytical Science and Technology
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    • v.12 no.3
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    • pp.230-234
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    • 1999
  • Barium titanyl oxalates (BTO) has been homogeneously prepared by thermal decomposition of dimethyl oxalate (DMO) in hydrochloric solution containing $Ba^{2+}$ and $Ti^{4+}$. Particles of BTO settled on the bottom of the beaker were collected at the aging time of 120 min using hydroxy propyl cellulose (HPC) as a dispersant. The reaction temperature, the concentration ratio of $[DMO]_0/([Ba^{2+}]_0+[Ti^{4+}]_0)$ and the existence of HPC were found to influence on morphologies of BTO, chemical yields and characteristics of barium titanates formed from their precursors.

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Studying Structural Evaluation of Web Link Structure and Performance in Destination Marketing Organizations (웹링크 구조와 웹사이트 성과간의 구조적 평가에 관한 연구: 컨벤션비지터뷰로(CVB)를 대상으로)

  • Joun, Hyo-Jae;Cho, Nam-Jae
    • Journal of Digital Convergence
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    • v.5 no.2
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    • pp.91-98
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    • 2007
  • Destination marketing organizations (DMO) have been building up the cyber city in the WWW. Website for DMO is a core channel to promote regional attractions. This research suggests the issue of criteria for evaluating DMO's performance in the Internet. The method of evaluation focuses on the structure in perspective of linkage based on small world theory and direct network. Convention & Visitors & Bureau (CVB) in tourism and travel industry playa role to promote and held the international meeting and exhibitions. CVB's websites evaluated according to web link structure and performance.

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Morphology of Barium Titanyl Oxalate Produced by Homogeneous Precipitation from Acidic Solution of Dimethyl Oxalate (Dimethyl Oxalate에 의한 균일 침전법으로 생성된 Barium Titanyl Oxalate의 형태학적 연구)

  • Min, Chonkyu;Lee, Chul
    • Analytical Science and Technology
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    • v.10 no.3
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    • pp.203-208
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    • 1997
  • Barium titanyl oxalate(BTO) was precipatated by utilizing the thermal decomposition of dimethyl oxalate in acidic aqueous solution having $BaCl_2$ and $TiCl_4$. Particle morphology of BTO was influeneced by the various experimental factors. i.e.. the faster rate to nucleation with higher temperature and the higher ratio of [DMO]/[$Ba^{2+}+Ti^{4+}$] was found to correspond to the faster rate of transformation of particle size distribution from unimodal to broad unimodal through bimodal. The BT powder obtained by calcination at $900^{\circ}C$ in air consists of larger particles than BT generated by general coprecipitation method and shows tetragonal symmetry. The stirring during reaction was also found to have much effect upon characteristics of BTO and BT.

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Influence of modification in core building procedure on fracture strength and failure patterns of premolars restored with fiber post and composite core

  • Kim, Young-Hoi;Lee, Jong-Hyuk
    • The Journal of Advanced Prosthodontics
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    • v.4 no.1
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    • pp.37-42
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    • 2012
  • PURPOSE. The influence of the modified process in the fiber-reinforced post and resin core foundation treatment on the fracture resistance and failure pattern of premolar was tested in this study. MATERIALS AND METHODS. Thirty-six human mandibular premolars were divided into 4 groups (n = 9). In group DCT, the quartz fibre post (D.T. Light-post) was cemented with resin cement (DUO-LINK) and a core foundation was formed with composite resin (LIGHT-CORE). In group DMO and DMT, resin cement (DUO-LINK) was used for post (D.T. Lightpost) cementation and core foundation; in group DMO, these procedures were performed simultaneously in one step, while DMT group was accomplished in separated two steps. In group LCT, the glass fiber post (LuxaPost) cementation and core foundation was accomplished with composite resin (LuxaCore-Dual) in separated procedures. Tooth were prepared with 2 mm ferrule and restored with nickel-chromium crowns. A static loading test was carried out and loads were applied to the buccal surface of the buccal cusp at a 45 degree inclination to the long axis of the tooth until failure occurred. The data were analyzed with MANOVA (${\alpha}$= .05). The failure pattern was observed and classified as either favorable (allowing repair) or unfavorable (not allowing repair). RESULTS. The mean fracture strength was highest in group DCT followed in descending order by groups DMO, DMT, and LCT. However, there were no significant differences in fracture strength between the groups. A higher prevalence of favorable fractures was detected in group DMT but there were no significant differences between the groups. CONCLUSION. The change of post or core foundation method does not appear to influence the fracture strength and failure patterns.

A Framework for Systematic Management of Operational Risks

  • Akpolat, Hasan;Pitinanondha, Thitima
    • International Journal of Quality Innovation
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    • v.10 no.2
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    • pp.1-17
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    • 2009
  • This paper presents a theoretical research framework that was used to analyse operational risk management (ORM) system practices in Australia. It provides a new perspective on how to use national and international operational management system standards as a basis for systematic management of operational risks. Based on the extensive literature review and the analysis of operational risk management system practices that are common in Australian organisations, this paper identifies the critical factors for effective use of an ORM system. The proposed framework could also be used as a model to research ORM system applications in other countries.

Cognitive IoT Computing Technology Trends (인지 IoT 컴퓨팅 기술동향)

  • Bae, M.N.;Lee, K.B.;Bang, H.C.
    • Electronics and Telecommunications Trends
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    • v.32 no.1
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    • pp.54-60
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    • 2017
  • 사물인터넷은 모든 사람과 사물이 인터넷을 통해 서로 소통하고 새로운 가치를 창출할 수 있는 기술이며, 정보의 확산, 연계, 활용을 가능하게 하는 중요한 연결고리이다. 인지 IoT는 이러한 사물인터넷 인프라와 함께 인공지능 기술을 활용하여, 사물이 스스로 생각하고 판단하며, 보다 잘 연결하고 더 똑똑해지도록 하는 사물지능 실현 기술이다. 본고는 인간 두뇌의 기능을 모방하여 인식, 행동, 인지 능력을 재현해내는 대표 인지 컴퓨팅 기술인 IBM 왓슨, 딥 러닝, 뉴로모픽칩 기술을 요약하며, 또한, 사물수준 지능 실현 사례인 IBM 쿼크, CISCO DMo와 D3의 개발 현황을 소개한다.

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