Browsing by Author "Wang, CF"

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An efficient multiple-path routing protocol for ad hoc networks
(2002-03-15)
Jiang, MH
;
Jan, RH
;
Wang, CF
;
資訊工程學系
;
Department of Computer Science
An ad hoc network is a cooperative engagement of a collection of mobile hosts that requires no intervening of any centralized access point or existing infrastructure, Each mobile host, operating as a specialized router, forwards packets from other mobile hosts. The possibility of fast movement of mobile hosts means network topologies may change frequently. Thus, applying traditional routing schemes to ad hoc networks is inappropriate. In this paper, we present an efficient routing protocol called the multiple next hops (MNH) routing protocol, which is based on the ad hoc on-demand distance vector (AODV) routing protocol for ad hoc networks. The proposed MNH protocol establishes multiple paths for a route discovery procedure, thus conserving network bandwidth and reducing route reconstruction times when routing paths fail. Numerical experiments are given to show the effectiveness of the MNH routing protocol. (C) 2002 Elsevier Science B.V. All rights reserved.
Fabrication of biomimetic super-amphiphobic surfaces through plasma modification of benzoxazine films
(2006-03-03)
Wang, CF
;
Chiou, SF
;
Ko, FH
;
Chou, CT
;
Lin, HC
In this study, a method for producing super-amphiphobic surfaces through plasma modification of benzoxazine films is presented. Microroughening and fluorination of the benzoxazine films occurs during the plasma treatment process and a rugged surface with a micro/nano binary structure is formed. The combined effect of low surface energy and substrate roughness results in high advancing contact angles (157 degrees for water, 152 degrees for diiodomethane) and low contact angle hysteresis.
Heuristic algorithms for packing of multiple-group multicasting
(2002-06-01)
Wang, CF
;
Liang, CT
;
Jan, RH
;
資訊工程學系
;
Department of Computer Science
Multicast communication is an efficient routing method for multimedia data distribution, since it can save network bandwidth during the communication session. Thus, the multicast routing problems have received much attention from many researchers. In this paper, we consider a multicast routing problem with multiple multicast sessions under a capacity limited constraint. This problem is formulated as a tree packing problem. We propose two heuristic algorithms, Steiner-tree-based heuristic (STH) algorithm and cut-set-based heuristic (CSH) algorithm, for solving this problem. The simulation results show that the STH algorithm can find a better approximate solution in a shorter computation time compared to CSH. In addition, if the available bandwidth for the service is just enough, the STH and CSH algorithms may fail to find a solution even if the solution exists. The simulation results also indicate that CSH has a higher probability than STH to find a solution. Thus, it is suggested that one can apply the STH algorithm first to solve the tree packing problem. In case STH fails, CSH algorithm will be used instead.
Influence of PMMA-chain-end tethered polyhedral oligomeric silsesquioxanes on the miscibility and specific interaction with phenolic blends
(2006-01-10)
Huang, CF
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Kuo, SW
;
Lin, FJ
;
Huang, WJ
;
Wang, CF
Two different molecular weights of poly(methyl methacrylate) (PMMA) and PMMA containing polyhedral oligomeric silsesquioxane (PMMA-POSS) homopolymers have been prepared via the atom transfer radical polymerization (ATRP) technique. The miscibility and specific interaction behaviors of PMMA-POSS and PMMA with phenolic resin were investigated by differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR). FTIR results reveal that at least three competing equilibriums are present in the phenolic/PMMA-POSS blend: self-association of phenolic (hydroxyl-hydroxyl), hydroxyl-siloxane interassociation between phenolic and POSS, and hydroxyl-carbonyl interassociation between phenolic and PMMA. Among these blends, single and higher T(g)s of these phenolic/PMMA-POSS blends were observed than the corresponding phenolic/PMMA blends at same composition, revealing that a stronger interassociation interaction of hydroxyl-siloxane than the hydroxyl-carbonyl interaction. Furthermore, we also found the screening effect in phenolic/LPMMA-POSS blends that tends to significantly decrease the hydrogen bond formation of the hydroxyl-carbonyl interassociation.
Low-surface-free-energy materials based on polybenzoxazines
(2006)
Wang, CF
;
Su, YC
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Kuo, SW
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Huang, CF
;
Sheen, YC
Optimum multicast of multimedia streams
(1999-04-01)
Wang, CF
;
Lai, BR
;
Jan, RH
;
資訊工程學系
;
Department of Computer Science
In a VOD system, multicast is a preferred method for saving network bandwidth. That is, customers requesting the same video program over a small time interval can be arranged in a multicast tree (group), and then the video server sends a video stream via this tree to customers. In this research, we considered how to arrange a set of multicast trees such that the number of customers served is maximized and the link capacity constraint is maintained. For a directed acyclic graph (DAG), we proposed a branch-and-bound algorithm to solve this problem and the solution method is illustrated by example. Next, we extended the algorithm to find an approximate solution for a general graph case. It is shown, through simulations on randomly generated graphs that the solution for our approximation method is very close to the optimal solution. (C) 1999 Elsevier Science Ltd. All rights reserved.
Suppression of boron penetration in BF2+-implanted poly-Si gate
(1996-12-01)
Chao, TS
;
Chu, CH
;
Wang, CF
;
Ho, KJ
;
Lei, TF
In this paper, a comprehensive study of gate engineering to suppress the penetration of boron in p-type metaloxide-semiconductor held-effect transistor (MOSFET) with the p(+)-poly-Si-gate is reported. Four types of poly-Si gate structure, two types of gate dielectrics were investigated to suppress the boron penetration. Among the different gate structures, the stacked amorphous silicon structure was found to be the most effective way to retard the boron penetration. N2O oxide exhibited a better retarding of the boron diffusion as compared with the O-2 oxide. It was found that a combination of stacked amorphous silicon with N2O oxide is the most effective way to suppress the boron penetration. Thermal stability, oxide integrity, and D-it of this sample are superior to all the other samples.
Suppression of boron penetration in BF2+-implanted poly-Si gate
(1996-12-01)
Chao, TS
;
Chu, CH
;
Wang, CF
;
Ho, KJ
;
Lei, TF
In this paper, a comprehensive study of gate engineering to suppress the penetration of boron in p-type metaloxide-semiconductor held-effect transistor (MOSFET) with the p(+)-poly-Si-gate is reported. Four types of poly-Si gate structure, two types of gate dielectrics were investigated to suppress the boron penetration. Among the different gate structures, the stacked amorphous silicon structure was found to be the most effective way to retard the boron penetration. N2O oxide exhibited a better retarding of the boron diffusion as compared with the O-2 oxide. It was found that a combination of stacked amorphous silicon with N2O oxide is the most effective way to suppress the boron penetration. Thermal stability, oxide integrity, and D-it of this sample are superior to all the other samples.