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1.
Three plain weave fabric composite analysis models are presented for the prediction of the on-axes thermal expansion coefficients. These are two-dimensional models in the sense that the actual strand cross-sectional geometry, strand undulation and the presence of a gap between the adjacent strands are taken into account. In the first two models, termed refined models, the representative unit cell is discretised into slices and elements and analysed. In the third method, a closed-form solution is presented. In this case, the representative unit cell is idealised as a crossply laminate and analysed. The relative merits and demerits of the models are also discussed. The predicted results are compared with the experimental values. A good correlation is observed. 相似文献
2.
Ganesh Thiagarajan 《Canadian Metallurgical Quarterly》2003,7(1):64-72
This paper presents the results of an experimental and analytical comparison of a study on the flexural behavior of concrete beams reinforced with sandblasted carbon fiber-based composite rods. Twelve beams, including three control beams reinforced with steel, were tested for strength, deformation, and failure characteristics. Analytical comparisons included the generation of the theoretical strength and moment curvature relations. Experimental data from pullout tests indicated that bonding of sandblasted rods is not a major concern. However, excessive deformation in achieving the predicted moment capacity could be a limiting factor in the design of these beams. 相似文献
3.
Probabilistic reliable dissemination in large-scale systems 总被引:2,自引:0,他引:2
Kermarrec A.-M. Massoulie L. Ganesh A.J. 《Parallel and Distributed Systems, IEEE Transactions on》2003,14(3):248-258
The growth of the Internet raises new challenges for the design of distributed systems and applications. In the context of group communication protocols, gossip-based schemes have attracted interest as they are scalable, easy to deploy, and resilient to network and process failures. However, traditional gossip-based protocols have two major drawbacks: 1) they rely on each peer having knowledge of the global membership; and 2) being oblivious to the network topology, they can impose a high load on network links when applied to wide-area settings. In this paper, we provide a theoretical analysis of gossip-based protocols which relates their reliability to key system parameters (the system size, failure rates, and number of gossip targets). The results provide guidelines for the design of practical protocols. In particular, they show how reliability can be maintained while alleviating drawback by: 1) providing each peer with only a small subset of the total membership information and drawback; and 2) organizing members into a hierarchical structure that reflects their proximity according to some network-related metric. We validate the analytical results by simulations and verify that the hierarchical gossip protocol considerably reduces the load on the network compared to the original, non-hierarchical protocol. 相似文献
4.
5.
The influence of black pepper (Piper nigrum L.) and its active principle, piperine on the secretion and composition of bile was investigated in the rat. They were administered by gavage (black pepper at 250 or 500 mg and piperine at 12.5 or 25 mg/kg body wt.) or fed in the diet for 4 weeks (black pepper at 0.2 and 0.4%, piperine at 0.01 and 0.02%). The lower dose by gavage of black pepper caused an increase in bile solids while with other treatments bile secretion or dry matter in bile was not changed. Dietary feeding of black pepper caused an increase in bile flow with a concomitant decrease in bile solids -- a hydrocholagoguic effect. Cholesterol and bile acid output were not affected by black pepper or piperine at either level irrespective of the mode of administration; in contrast, the secretion of uronic acids in bile was enhanced by both levels of pepper as also of piperine indicating possible excretion of some of the components of black pepper or of piperine as glucuronides. 相似文献
6.
The position control system of an electro-hydraulic actuator system (EHAS) is investigated in this paper. The EHAS is developed by taking into consideration the nonlinearities of the system: the friction and the internal leakage. A variable load that simulates a realistic load in robotic excavator is taken as the trajectory reference. A method of control strategy that is implemented by employing a fuzzy logic controller (FLC) whose parameters are optimized using particle swarm optimization (PSO) is proposed. The scaling factors of the fuzzy inference system are tuned to obtain the optimal values which yield the best system performance. The simulation results show that the FLC is able to track the trajectory reference accurately for a range of values of orifice opening. Beyond that range, the orifice opening may introduce chattering, which the FLC alone is not sufficient to overcome. The PSO optimized FLC can reduce the chattering significantly. This result justifies the implementation of the proposed method in position control of EHAS. 相似文献
7.
Ganesh R. Baliga Anil M. Shende 《Annals of Mathematics and Artificial Intelligence》1996,17(2):177-187
A class of recursive functionsC islimiting standardizable, in a programming system , iff there is an effective procedure which, given any -program (in the -system), synthesizes in the limit acanonical -program which is equivalent to the former. It can arguably be expected that notions similar to the above one would be relevant toGold-style function learning, which features, among other things, the effective limiting synthesis of programs for input recursive functions. Many learning classes have been characterized in terms of variants of the above notion. In this paper, we focus on the limiting standardizability of the entire class of recursive functions inEffective programming systems. To start with, we prove the independence of this notionvis-à-vis finitary recursion theorems. Secondly, we show that this motion does not entail acceptability, in the spirit of the results of Case, Riccardi and Royer on characterizations of the samevis-à-vis programming language control structures. 相似文献
8.
This work describes initial efforts to incorporate affinity ligands within an environmentally responsive hydrogel. Metal affinity ligands were chosen as model affinity groups and thermally responsive N‐isopropyl acrylamide/acrylamide copolymers were used as the base hydrogels. The ? NH2 group of the acrylamide serves as a reactive group for functionalization with metal affinity ligands. The gels were synthesized by free radical polymerization and Cu2+ was bound to the gel via 1,4‐butanediol diglycidyl ether (BDE) as a linker and iminodiacetic acid (IDA) as a chelating ligand. The base acrylamide gels were also functionalized with metal affinity ligands to allow for comparison with thermally responsive affinity gels. The results show the effectiveness of this technique for both these types of gels, and an improved method to immobilize metal affinity groups on to thermally sensitive N‐isopropyl acrylamide gels was also developed. It was seen that the yields for the reaction with BDE decreased with increased reaction time in both kinds of gels, whereas reaction with IDA showed a decrease in yields with increase in temperature for N‐isoporpyl acrylamide gels and increase in yields for acrylamide gels. Further techniques were developed to overcome diffusional resistances and stresses in the thermally responsive N‐isopropyl acrylamide gels so as to improve the distribution of Cu2+ ions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
9.
Rajamani Ganesh Kuriacose Joseph Newman D. Wilson Dipankar Raychaudhuri 《International Journal of Wireless Information Networks》1994,1(3):199-222
This paper presents a simulation-based study of cellular packet CDMA systems operating in an integrated voice/data traffic scenario. Spread-spectrum CDMA provides a suitable framework for resource-shared packet transport capable of combining isochronous (voice, ISDN) and bursty data services. In this work, a general network model for cellular packet CDMA with mixed voice/data traffic is described and used to evaluate the capacity/performance impact of several key system parameters. First, the effect of spreading factor (N) and forward error correction (FEC) rate are studied, confirming earlier work indicating a weak dependence onN and a well-defined optimum code rate in the range of 0.5–0.7 (with BCH coding). Next, the effect of propagation loss coefficient () on network capacity is investigated over a range of possible assumptions for, including both constant and distance-dependent models. The results show that system capacity depends strongly on, varying by as much as a factor of 2 over the range of parameters considered. For a given distance-dependent assumption, performance results are also obtained for different cell sizes in order to understand the overall spatial reuse efficiency achievable in different cellular and microcellular scenarios. This is followed by an investigation of traffic source model effects: first the capacity improvement from voice activity detection VAD) is presented, showing the expected 21 gains. Results for varying proportions of voice and data traffic intensities indicate that the operating efficiency does not change significantly as the proportion of bursty data relative to voice is varied. 相似文献
10.
Ganesh Swain Ravi Kumar Sonwani Balendu Shekhar Giri Ram Sharan Singh Ravi Prakash Jaiswal Birendra Nath Rai 《Water and Environment Journal》2021,35(1):285-294
The impact of external mass transport on the biodegradation rate of phenol in a packed bed bioreactor (PBBR) was studied. A potential bacterial species, Bacillus flexus GS1 IIT (BHU), was isolated from the petroleum‐contaminated soil. Low‐density polyethylene (LDPE) immobilized with the B. flexus GS1 IIT (BHU) was used as packing material in the PBBR. The PBBR was operated by varying the inlet feed flow rate from 4 to 10 mL/min, and the corresponding degradation rate coefficients were found to be in the range of 0.119–0.157 L/g h. In addition, the highest removal rate of phenol was obtained to be 1.305 mg/g h at an inlet feed rate of 10 mL/min. The external mass transfer was studied using the model . A new empirical correlation for the biodegradation of phenol in the PBBR was developed after the evaluation at various values of K and n. 相似文献