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41.
The wave energy potential is directly proportional to the wave period and second power of wave height averaged over a suitable time period. The wave height and period have temporal and spatial stochastic variations. It is the main purpose of this paper to derive the most general wave energy formulation by considering simultaneously the temporal variations both in the wave height and period. The correction factor is derived explicitly in terms of cross-correlation and the coefficients of variation. The application of the methodology is performed for wave measurement stations located in the Pacific Ocean off the west coast of the US. 相似文献
42.
Scientometrics - A novel hashing algorithm is applied to match two prominent and important bibliographic databases at the paper level. In the literature, such tasks have been studied and conducted... 相似文献
43.
The Internet not only facilitates our daily activities, such as communication, entertainment and shopping but also serves as the enabling technology for many critical services, including finance, manufacturing, healthcare and transportation. On the other hand, a wide spectrum of attacks targets its communication infrastructure to disable or disrupt the network connectivity and traffic flow until recovery processes take place. Attacking all autonomous systems (ASes) in the Internet is typically beyond the capability of an adversary. Therefore, targeting a small number of ASes which results in the highest impact is the best strategy for attackers. Similarly, it is important for network practitioners to identify, fortify and secure those critical ASes to mitigate the impact of the attacks. In this study we introduce an intuitive and effective measure, IP address spatial path stress centrality, to assess and identify the critical ASes in the Internet. We compare IP address spatial path stress centrality to the three well-known and widely used centrality measures, namely customer-cone size, node degree and betweenness. We demonstrate that the proposed measure incorporates business relations and IP address spaces to achieve a better measure for identifying the critical ASes in the Internet. 相似文献
44.
In this study, experimental neutron-emission spectra produced by (n, xn) reactions on nuclei 232Th have been compared with experimental 238U(n, xn) neutron-emission spectra from 2 to 18 MeV. Angle-integrated cross-sections in neutron induced reactions on targets 238U have been calculated at the bombarding energies from 2 to 18 MeV. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach–Kerman-Koonin (FKK) fully quantum-mechanical theory. By analyzing (n, xn) reaction on 238U with the incident energy from 2 to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other. 相似文献
45.
Mehmet Kodal Hümeyra Şirin Bağdagül Karaağaç Güralp Özkoç 《Polymer Engineering and Science》2020,60(8):1958-1972
The aim of this article is to improve the interfacial adhesion between silicone rubber (SR) and Rayon fiber by the help of functional hybrid POSS nanoparticles. Two POSS types were compared, octavinyl-POSS (O-POSS) and methacryl-POSS (M-POSS), having reactive CC double bonds that can impart in peroxide crosslinking. O-POSS is nonpolar, whereas M-POSS is polar and is able to make H-bond with Rayon fibers. POSS type and their concentrations were examined as the experimental parameters. H-adhesion tests indicated that both POSS types enhanced the adhesion of SR composites to Rayon fibers compared with control recipe. Specifically, slightly higher values were obtained with the use of M-POSS. It was observed that both O-POSS and M-POSS slowed down the curing rate but increased the degree of crosslinking. The cure extent of O-POSS containing composites was found to be higher than that of M-POSS containing ones. Thermal gravimetric analyses revealed that thermal stability of SR composites was significantly improved by the addition of POSS particles. Higher char yield and degradation temperatures were obtained with O-POSS at higher loadings with respect to M-POSS. The POSS distribution at lower loading levels was found to be homogenous for both POSS types as observed from scanning electron microscope and transmission electron microscope. 相似文献
46.
47.
Anjan Biswas Sonmezoglu Abdullah Ekici Mehmet Alzahrani Abdullah Khamis Belic Milivoj R. 《Journal of Communications Technology and Electronics》2020,65(12):1384-1398
Journal of Communications Technology and Electronics - This paper implements mathematically rigorous extended trial function algorithm to address cubic–quartic optical solitons in... 相似文献
48.
49.
In this paper, sliding mode control (SMC) is designed and applied to an elastic structure to suppress some of its vibration
modes. The system is an elastic beam clamped on one end and the designed controller uses only the deflection measurement of
the free end. The infinite dimensional mathematical model of the beam is reduced to an ordinary differential equation set
to represent the behavior of required modes. Since the states of the finite dimensional model are not physically measurable
quantities, an observer is designed to estimate these states by measuring the tip deflection of the beam. The performance
of the observer is important because the observed states are used in the SMC design. In this study, by using the output information,
an observer is designed and tested to estimate the states of the finite dimensional model of the beam. Then the designed SMC
is applied to the experimental beam system which gives satisfactory suppressed vibrations. 相似文献
50.
Mehmet Erdi Korkmaz Patricia Verleysen Mustafa Günay 《Transactions of the Indian Institute of Metals》2018,71(12):2945-2952
Nimonic 80A is a nickel-chrome superalloy, commonly used due to its high resistance against creep, oxidation, and temperature corrosion. This paper presents the material constitutive models of Nimonic 80A superalloy. Johnson–Cook (JC) and modified JC model is preferred among the different material constitutive equations (Zerill Armstrong, Bodner Partom, Arrhenius type) due to its accuracy in the literature. Three different types of compression tests were applied to determine the equation parameters. Firstly, quasi-static tests were performed at room temperature. These tests were conducted at 10?3, 10?2, and 10?1 s?1 strain rates. Secondly, compression tests were performed at room temperature at high strain rates (370–954 s?1) using the Split-Hopkinson pressure bar. Finally, compression tests were performed at a temperature level from 24 to 200 °C at the reference strain rate (10?3 s?1). Johnson–Cook and modified JC model parameters of Nimonic 80A were determined with the data obtained from these tests, and they were finally verified statistically. 相似文献