Moleculardynamics (Md) was used to simulate dissociative adsorption of a hydrogen molecule on the Pt(111) surface considering the movement of the surface atoms and gas molecules. The Embedded Atom Method (EAM) was ap...
Moleculardynamics (Md) was used to simulate dissociative adsorption of a hydrogen molecule on the Pt(111) surface considering the movement of the surface atoms and gas molecules. The Embedded Atom Method (EAM) was applied to represent the interaction potential. The parameters of the EAM potential were determined such that the values of the dissociation barrier at different sites estimated by the EAM potential agreed with that of dFT calculation results. A number of Md simulations of gas molecules impinging on a Pt(111) surface were carried out randomly changing initial orientations, incident azimuth angles, and impinging positions on the surface with fixed initial translational energy, initial rotational energy, and incident polar angle. The number of collisions in which the gas molecule was dissociated were counted to compute the dissociation probability. The dissociation probability was analyzed and expressed by a mathematical function involving the initial conditions of the impinging molecule, namely the translational energy, rotational energy, and incident polar angle. Furthermore, the utility of the model was verified by comparing its results with raw Md simulation results of molecular beam experiments.
The original online version of this article （Journal of Electronics （China）, Vol. 28, No.3, May 2011, pp.389-395; dOI： 10.1007/s11767-011-0549-1） unfortunately contains a mistake on the author affiliation of Page...
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The original online version of this article （Journal of Electronics （China）, Vol. 28, No.3, May 2011, pp.389-395; dOI： 10.1007/s11767-011-0549-1） unfortunately contains a mistake on the author affiliation of Page 389. The correct form is given below：
This paperdescribes implementation of the expert system on estimating fatigue properties from simple tensile data or hardness data. The fatigue properties are usually obtained by performing fatigue tests. However, as...
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This paperdescribes implementation of the expert system on estimating fatigue properties from simple tensile data or hardness data. The fatigue properties are usually obtained by performing fatigue tests. However, as fatigue test requires time and high cost, many methods have been proposed to estimate the strain-life curves from monotonic mechanical properties including hardness. Though many useful estimation methods have been proposed and they afford every facility, a mechanical designer has some difficulties in making a decision to select the best method among the several methods for the fatigue strength design or assessment under given conditions. And then several researchers including authors evaluated the methods and proposed the best method according to material. In spite of those guidelines, it does not seem to be always easy for ordinary mechanical designer to apply. In this study, an expert system was developed to facilitate it. A commercial expert system shell, Acquire, was used and the user interfaces of the expert system were developed using Visual Basic. The expert system helps mechanical designer to select the best estimation method among methods for estimating fatigue properties from monotonic mechanical properties including hardness, depending on his or her knowledge level of fatigue and has some special functions to describe recommendation andremarks in detail anddisplay the accuracy and predictability of estimation method.
Microphase separated structures of block copolymer, polystyrene-b-polyisoprene (PS-b-PI, PS = 14%) including non-volatile selective solvent thin films were investigated using grazing incidence small angle X-ray scatte...
Microphase separated structures of block copolymer, polystyrene-b-polyisoprene (PS-b-PI, PS = 14%) including non-volatile selective solvent thin films were investigated using grazing incidence small angle X-ray scattering technique. The diethyl phthalate (dEP) was used as a non-volatile selective solvent which solves PS only. The dEP swelled PS phase selectively and the microphase separated structure transited from the PS spherical domain to the lamellardomain with an increase in dEP content in the bulk state. Similarly, the phase separated structure in the thin film prepared by spin cast on a silicon wafer from the mixture of toluene/dEP and block copolymer changed according to the initial dPE concentration. However, the morphologies developed in the thin film were shifted to the structures at lowerdEP concentration than that expected from the initial concentration. Moreover, the cylindrical and lamellardomains were aligned parallel and perpendicularly to the substrate, respectively.
Available bandwidth estimation is a vital component of admission control for quality-of-service (QoS) in networks, it seek to provide an accurate estimation of available bandwidth such that network applications can ad...
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Available bandwidth estimation is a vital component of admission control for quality-of-service (QoS) in networks, it seek to provide an accurate estimation of available bandwidth such that network applications can adjust their behavior accordingly. Wireless ad hoc networks employing the IEEE 802.11 protocol in distributedcoordination Function (dCF) mode are becoming increasingly popular. In this paper, an available bandwidth estimation scheme for IEEE 802.11- based ad hoc network is presented. Our scheme does not modify the CSMA/CA MAC protocol in any manner, but gauges the effect of phenomena such as medium contention, channel interference, which influence the available bandwidth, on it. Based on the effect of the phenomena on the working of the medium-access scheme, we estimate the available bandwidth of a wireless host to each of its neighbors. The result of simulation shows that the scheme is efficiently.
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