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91.
Social online communities and platforms play a significant role in the activities of software developers either as an integral part of the main activities or through complimentary knowledge and information sharing. As such techniques become more prevalent resulting in a wealth of shared information, the need to effectively organize and sift through the information becomes more important. Top-down approaches such as formal hierarchical directories have shown to lack scalability to be applicable to these circumstanes. Light-weight bottom-up techniques such as community tagging have shown promise for better organizing the available content. However, in more focused communities of practice, such as software engineering and development, community tagging can face some challenges such as tag explosion, locality of tags and interpretation differences, to name a few. To address these challenges, we propose a semantic tagging approach that benefits from the information available in Wikipedia to semantically ground the tagging process and provide a methodical approach for tagging social software engineering content. We have shown that our approach is able to provide high quality tags for social software engineering content that can be used not only for organizing such content but also for making meaningful and relevant content recommendation to the users both within a local community and also across multiple social online communities. We have empirically validated our approach through four main research questions. The results of our observations show that the proposed approach is quite effective in organizing social software engineering content and making relevant, helpful and novel content recommendations to software developers and users of social software engineering communities. 相似文献
92.
This study aimed to evaluate the cytotoxicity effects of various polyethylene glycols (PEGs), and construction and characterization of polybutylcyanoacrylate (PBCA) nanoparticles. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on rat glioma C6 cell line, and PBCA nanoparticles were prepared by emulsion polymerization method. Also, the nanoparticles were characterized by dynamic light scattering and scanning electron microscopy. The findings showed that PEGs were approximately safe and cytotoxicity was inversely proportional with their molecular weights. In addition, the size of nanoparticles were increased with reducing molecular weights of PEGs. PEGs with negligible cytotoxicity and stabilizing functionality were demonstrated in this study. 相似文献
93.
Influences of nonassociated flow rules on three-dimensional seismic stability of loaded slopes 总被引:1,自引:1,他引:0
The influences of soil dilatancy angle on three-dimensional (3D) seismic stability of locally-loaded slopes in nonassociated flow rule materials were investigated using a new rotational collapse mechanism and quasi-static coefficient concept. Extended Bishop method and Boussinesq theorem were employed to establish the stress distribution along the rupture surfaces that are required to obtain the rate of internal energy dissipation for the nonassociated flow rule materials in rotational collapse mechanisms. Good agreement was observed by comparing the current results with those obtained using the translational or rotational mechanisms and numerical finite difference method. The results indicate that the seismic stability of slopes reduces by decreasing the dilatancy angle for nonassociated flow rule materials. The amount of the mentioned decrease is more significant in the case of mild slopes in frictional soils. A nearly infinite slope under local loading, whether its critical failure surface is 2D or 3D, not only depends on the magnitude of the external load, but also depends on the dilatancy angle of soil and the coefficient of seismic load. 相似文献
94.
Faezeh Farivar Mahdi Aliyari Shoorehdeli Mohammad Ali Nekoui Mohammad Teshnehlab 《Expert systems with applications》2011,38(5):4714-4726
This paper proposes the generalized projective synchronization (GPS) of uncertain chaotic systems with external disturbance via Gaussian radial basis adaptive sliding mode control (GRBASMC). A sliding surface is adopted to ensure the stability of the error dynamics in sliding mode control. In the neural sliding mode controller, a Gaussian radial basis function is utilized to online estimate the system dynamic function. The adaptation law of the control system is derived in the sense of Lyapunov function, thus the system can be guaranteed to be asymptotically stable.The proposed method allows us to arbitrarily adjust the desired scaling by controlling the slave system. It is not necessary to calculate the Lyapunov exponents and the eigen values of the Jacobian matrix, which makes it simple and convenient. Also, it is a systematic procedure for GPS of chaotic systems and it can be applied to a variety of chaotic systems no matter whether it contains external excitation or not. Note that it needs only one controller to realize GPS no matter how much dimensions the chaotic system contains and the controller is easy to be implemented.The proposed method is applied to three chaotic systems: Genesio system, Lur’e like system and Duffing system. 相似文献
95.
Sedimentation is thought to be one of the mechanisms of microbial reduction from wetlands used for wastewater treatment. This study compared the occurrence and survival of enteric indicator microorganisms and pathogens in the water column and sediments of two constructed surface flow wetlands in Arizona. On a volume/wet weight basis the concentration of fecal coliforms and coliphage in the water column and sediment was similar. However, on a volume/dry weight basis the numbers were one to two orders of magnitude higher in the sediment. Giardia cyst and Cryptosporidium oocyst concentrations were one to three orders of magnitude greater in the sediment compared to the water column. The die-off rates of all the bacteria and coliphage were greater in the water column than the sediment. The die-off rates of fecal coliforms in the water and sediment were 0.256log(10)day(-1) and 0.151log(10)day(-1), respectively. The die-off rates of Salmonella typhimurium in the water and sediment were 0.345log(10)day(-1) and 0.312log(10)day(-1), respectively. The die-off rates of naturally occurring coliphage in water column and sediment were 0.397log(10)day(-1) and 0.107log(10)day(-1), respectively, and the die-off rates of and PRD-1 in water and sediment were 0.198log(10)day(-1) and 0.054log(10)day(-1), respectively. In contrast Giardia die-off in the sediment was greater compared to the water column. The die-off rates of Giardia in water and sediment were 0.029log(10)day(-1) and 0.37log(10)day(-1), respectively. Coliphage survived the longest of any group of organisms in the sediment and the least in the water column. In contrast Giardia survived best in the water column and least in the sediment. 相似文献
96.
Mohammad Taghi Taghizadeh Faezeh Nejhad-babaie Kheljan Morteza Vatanparast 《Journal of Materials Science: Materials in Electronics》2018,29(2):978-984
In the present study, a facile ultrasonic-assisted method was developed for the synthesis of ZnO/NiO nanocomposites. The X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, diffuse reflectance spectroscopy and Fourier transform infrared spectroscopy techniques was applied for characterization of structure, purity, morphology and optical properties of the resultant samples. The photocatalytic performance of the synthesized ZnO/NiO nanocomposites was evaluated by monitoring the photodegradation of Rhodamine B (RhB) under UV light irradiation. Moreover, the influence of various parameters, such as molar percentage of NiO to ZnO, initial RhB concentration, pH of solution and photocatalyst weight was studied. The results show that the photocatalytic activity of the ZnO/NiO nanocomposite was higher than that of pure ZnO and NiO. 相似文献
97.
Faezeh Ebrahimzadeh Min-Ching Chung Ying Ting Liao Leang-San Shieh 《International journal of systems science》2017,48(2):397-416
Contrastive to Part 1, Part 2 presents a generalised optimal linear quadratic digital tracker (LQDT) with universal applications for the discrete-time (DT) systems. This includes (1) a generalised optimal LQDT design for the system with the pre-specified trajectories of the output and the control input and additionally with both the input-to-output direct-feedthrough term and known/estimated system disturbances or extra input/output signals; (2) a new optimal filter-shaped proportional plus integral state-feedback LQDT design for non-square non-minimum phase DT systems to achieve a minimum-phase-like tracking performance; (3) a new approach for computing the control zeros of the given non-square DT systems; and (4) a one-learning-epoch input-constrained iterative learning LQDT design for the repetitive DT systems. 相似文献
98.
99.
Yadollah Farzaneh Alireza Akbarzadeh Ali Akbar Akbari 《Intelligent Service Robotics》2012,5(3):169-177
In this paper, we suggest a new supervised learning method called Fourier based automated learning central pattern generators (FAL-CPG), for learning rhythmic signals. The rhythmic signal is analyzed with Fourier analysis and fitted with a finite Fourier series. CPG parameters are selected by direct comparison with the Fourier series. It is shown that the desired rhythmic signal is learned and reproduced with high accuracy. The resulting CPG network offers several advantages such as, modulation and robustness against perturbation. The proposed learning method is simple, straightforward and efficient. Furthermore, it is suitable for on-line applications. The effectiveness of the proposed method is shown by comparison with four other supervised learning methods as well as an industrial robotic trajectory following application. 相似文献
100.
Farzaneh Aminpour Payam Kabiri Mohammad Ali Boroumand Abbas Ali Keshtkar Seyed Shamsoddin Hejazi 《Scientometrics》2010,85(1):53-63
Patenting and licensing is not only a significant method of university knowledge transfer, but also an important indicator
for measuring academic R&D strength and knowledge utilization. The methodologies of quantitative and qualitative analysis,
including a special patent h-index indicator to assess patenting quality, were used to examine university patenting worldwide. Analysis of university
patenting from 1998 to 2008 showed a significant overall global increase in which Chinese academia stands out: most of the
top 20 universities in patenting in 2008 were in China. However, a low rate of utilization of Chinese academic patents may
have roots in: (1) university research evaluation system encourages the patent production more, rather than the utilization;
(2) problems in the formal mechanisms for university technology transfer and licensing, (3) industry’s limited expectation
and receptive capabilities and/or (4) a mismatch between the interests of the two institutional spheres. The next action to
be taken by government, university and industry in China will be to explore strategies for improving academic patent quality
and industry take-up. 相似文献