• 제목/요약/키워드: heterogeneous

검색결과 4,851건 처리시간 0.033초

일반 Batho방법의 부정형 이질조직에의 적용 (Application of Generalized Batho Method to Arbitrary Shape of Heterogeneous Tissues)

  • 채규영
    • Radiation Oncology Journal
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    • 제5권2호
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    • pp.165-168
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    • 1987
  • The generalized Bathe method, proposed by Webb and Fox, which is a method of calculation of dose correction factor for the purpose of heterogeneous tissue, is complex even for a few kind of tissues. The method was modified for the purpose of getting a simple method that divide the multilayer of heterogeneous tissues into some groups of adjacent-tissue pairs. This new method could reduce the number of exponential terms and the time for calculating the dose correction factors by manual and computer calculation.

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Polystyrene Supported Al(OTf)3: an Environmentally Friendly Heterogeneous Catalyst for Friedel-Crafts Acylation of Aromatic Compounds

  • Boroujeni, Kaveh Parvanak
    • Bulletin of the Korean Chemical Society
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    • 제31권11호
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    • pp.3156-3158
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    • 2010
  • Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.

이기종 환경을 위한 응용 프로그램 공유서버의 설계 및 구현 (The design and implementation of application sharing server for heterogeneous environment)

  • 이창욱;박용진
    • 전자공학회논문지B
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    • 제33B권7호
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    • pp.51-59
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    • 1996
  • The current network environment is composed of heterogeneous H/W and S/W resources. Integrating CSCW applications in such heterogeneous environments is highly complex. This paper describes the design and implementation of ASS (application sharing server) which supprot sharing of a single application between different operating systems. The ASS supports cooperative work among user group using its own window system (X-windwo or MS-windwos). We adopted improved managing heavy-weight data. ASS also provides development environment for vaious groupware application.

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불균일 촉매를 이용한 부식산의 오존 처리 (Ozonation of Humic Acid with Heterogeneous Catalysts)

  • 이동석
    • 산업기술연구
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    • 제29권A호
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    • pp.89-94
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    • 2009
  • The efficiency of heterogeneous catalysts has been investigated in ozonation process for organic removal. Heterogeneous catalytic ozonation was conducted for the degradation of humic acid in the presence of Granular Activated Carbon or Zeolite as a solid catalyst. And the results were compared to those of ozonation alone and adsorption alone without ozonation. The degradation characteristics of humic acid in each process were examined with the values of pH, TOC, $UV_{254}$ and $COD_{Cr}$.

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이종 다수의 네트워크 기반 휴머노이드를 위한 협조제어 소프트웨어 프레임워크 (Framework of a Cooperative Control Software for Heterogeneous Multiple Network Based Humanoid)

  • 임헌영;강연식;이중재;김종원;유범재
    • 로봇학회논문지
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    • 제3권3호
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    • pp.226-236
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    • 2008
  • In this paper, control software architecture is designed to enable a heterogeneous multiple humanoid robot demonstration executing tasks cooperating with each other. In the heterogeneous humanoid robot team, one large humanoid robot and two small humanoid robots are included. For the efficient and reliable information sharing between many software components for humanoid control, sensing and planning, CORBA based software framework is applied. The humanoid tasks are given in terms of finite state diagram based human-robot interface, which is interpreted into the XML based languages defining the details of the humanoid mission. A state transition is triggered based on the event which is described in terms of conditions on the sensor measurements such as robot locations and the external vision system. In the demonstration of the heterogeneous humanoid team, the task of multiple humanoid cleaning the table is given to the humanoid robots and successfully executed based on the given state diagram.

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Optimal Opportunistic Spectrum Access with Unknown and Heterogeneous Channel Dynamics in Cognitive Radio Networks

  • Zhang, Yuli;Xu, Yuhua;Wu, Qihui;Anpalagan, Alagan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권8호
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    • pp.2675-2690
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    • 2014
  • We study the problem of optimal opportunistic spectrum access with unknown and heterogeneous channel dynamics in cognitive radio networks. There is neither statistic information about the licensed channels nor information exchange among secondary users in the respective systems. We formulate the problem of maximizing network throughput. To achieve the desired optimization, we propose a win-shift lose-stay algorithm based only on rewards. The key point of the algorithm is to make secondary users tend to shift to another channel after receiving rewards from the current channel. The optimality and the convergence of the proposed algorithm are proved. The simulation results show that for both heterogeneous and homogenous systems the proposed win-shift lose-stay algorithm has better performance in terms of throughput and fairness than an existing algorithm.

A scheme on multi-tier heterogeneous networks for citywide damage monitoring in an earthquake

  • Fujiwara, Takahiro;Watanabe, Takashi;Shinozuka, Masanobu
    • Smart Structures and Systems
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    • 제11권5호
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    • pp.497-510
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    • 2013
  • Quick, accurate damage monitoring is strongly required for damage assessment in the aftermath of a large natural disaster. Wireless sensor networks are promising technologies to acquire damage information in a citywide area. The wireless sensor networks, however, would be faced with difficulty to collect data in real-time and to expand the scalability of the networks. This paper discusses a scheme of network architecture to cove a whole city in multi-tier heterogeneous networks, which consist of wireless sensor networks, access networks and a backbone network. We first review previous studies for citywide damage monitoring, and then discuss the feature of multi-tier heterogeneous networks to cover a citywide area.

Analytical Approach of Proxy-LMA Mobility System in Heterogeneous IP-based Mobile Networks

  • Cho, Chulhee;Choi, Jae-Young;Jeong, Jongpil
    • International journal of advanced smart convergence
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    • 제4권1호
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    • pp.71-87
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    • 2015
  • Mobile users want to be provided with undisrupted network services when they navigate on the Next-Generation (NG) wireless networks. For that, interlocking with a heterogeneous network is important, but there have been few studies on the method for guaranteeing global mobility. Thus, this paper proposes the Proxy-LMA technique, the mobile IP-based global inter-networking system, to enhance global mobility and interoperability within the Next-Generation (NG) network environment. The purpose of the proposed Proxy-LMA system is to expand the boundary of the mobility with regards to the existing mobility management protocol (PMIPv6 and MIPv6) in order to guarantee global mobility and interoperability within the heterogeneous network environment. The results of the performance evaluation showed that the proposed Proxy-LMA system was more efficient than other methods from the standpoint of signaling cost and delay in the heterogeneous network environment.

A Distributed Power Allocation Scheme for Base Stations Powered by Retailers with Heterogeneous Renewable Energy Sources

  • Jeon, Seung Hyun;Lee, Joohyung;Choi, Jun Kyun
    • ETRI Journal
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    • 제38권4호
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    • pp.746-756
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    • 2016
  • Owing to the intermittent power generation of renewable energy sources (RESs), future wireless cellular networks are required to reliably aggregate power from retailers. In this paper, we propose a distributed power allocation (DPA) scheme for base stations (BSs) powered by retailers with heterogeneous RESs in order to deal with the unreliable power supply (UPS) problem. The goal of the proposed DPA scheme is to maximize our well-defined utility, which consists of power satisfaction and unit power costs including added costs as a non-subscriber, based on linear and quadratic cost models. To determine the optimal amount of DPA, we apply dual decomposition, which separates the master problem into sub-problems. Optimal power allocation from each retailer can be obtained by iteratively coordinating between the BSs and retailers. Finally, through a mathematical analysis, we show that the proposed DPA can overcome the UPS for BSs powered from heterogeneous RESs.