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111.
Dilan Aksoy-Yurdagul 《Industry and innovation》2015,22(1):1-17
Vendors of proprietary software products are increasingly moving to business models inspired by open source software (OSS). This study investigates sources of heterogeneity in value appropriation associated with commercializing OSS. Specifically, I suggest that the relationship between a firm's OSS releases and its value depends critically on its stocks of protection mechanisms for intellectual property rights, such as software patents and software trademarks. I find that while software patent stocks positively affect the relationship between a firm's OSS product portfolio and its value, software trademark stocks have a negative effect on this relationship. 相似文献
112.
Mert Aydın Y. Samim Ünlüsoy 《The International Journal of Advanced Manufacturing Technology》2012,60(5-8):743-754
This paper illustrates the development and implementation of a parameter optimization methodology to improve impact harshness (IH) of road vehicles. A full ADAMS model of a small commercial vehicle is used as the IH test vehicle. The methodology involves the use of design of experiments methods together with response surface methodology. Significant design parameters affecting IH of the vehicle are first determined by the screening experiments. Once the critical parameters are identified, they are optimized to achieve improvement in the IH by constructing response surface. The optimization results indicate that the selected suspension parameters are capable of improving IH performance of the full vehicle ADAMS model by minimizing longitudinal and vertical acceleration responses. The results also show that considerable improvement can be obtained by using the proposed parameter optimization methodology. 相似文献
113.
114.
This paper makes a new conceptualization on Caspian energy system and the transit routes that pass through Turkey. Firstly, it puts forward the term of “inner-Caspian”, comprising Azerbaijan, Kazakhstan and Turkmenistan. Secondly, it identifies sub-systems of “western energy corridor through Turkey” (WECT) by diversifying: (1) “WECT inner-Caspian”, which includes hydrocarbon transportation from Azerbaijan, Kazakhstan and Turkmenistan; (2) “WECT Russia”, which is currently composed of Blue Stream gas pipeline and oil transportation by tankers through Turkish straits; and (3) “WECT Middle East”, which refers to Iranian, Iraqi and Egyptian hydrocarbons. Thirdly, this paper makes a comparative analysis on WECT systems through selected economic (reserves, supply/demand, production and transportation costs), geo-political (e.g. moves of the concerned actors), political (e.g. recent developments in government structures) and security (especially in terms of transport) indicators which bring out that “it is more reasonable for the EU to first embrace WECT inner-Caspian, then develop WECT Middle-East in order to diversify its energy supply”. 相似文献
115.
Video sequences are major sources of traffic for broadband ISDN networks, and video compression is fundamental to the efficient
use of such networks. We present a novel neural method to achieve real-time adaptive compression of video. This tends to maintain
a target quality of the decompressed image specified by the user. The method uses a set of compression/decompression neural
networks of different levels of compression, as well as a simple motion-detection procedure. We describe the method and present
experimental data concerning its performance and traffic characteristics with real video sequences. The impact of this compression
method on ATM-cell traffic is also investigated and measurement data are provided. 相似文献
116.
Porous polymer composites have been synthesized by polymerizing the continuous phase of styrene/divinylbenzene high internal phase emulsions in the presence of organophilic montmorillonite clay having a novel oil‐based intercalant which is a reactive methacryl derivative of quaternized methyl oleate. The morphological features, thermal stability and mechanical properties, namely compression modulus and crush strength of the resulting composites have been investigated as a function of degree of nanoclay loading. All the composites reinforced with the clay were found to have improved thermal and mechanical properties as well as desired porous and interconnected structural morphology, as compared with the bare polyHIPE matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41333. 相似文献
117.
This study investigates the proton conductivity and characterization of nano hexagonal boron nitride–Nafion composite membranes. Proton conducting composite membranes are prepared by mixing Nafion and nano hexagonal boron nitride (NhBN) particles with 3, 5, 10, and 15% weight ratios. Particle size distribution analysis is made for BN nanoparticles and the homogeneity of the membranes is proved by SEM and AFM. FTIR confirms the interaction between NhBN and Nafion. Methanol permeation and water absorption tests are made and it shows that hydrophobic NhBN particles decrease the swelling property and methanol retention of the membranes. X‐ray investigation of the composites supports semi‐crystalline nature of the composite materials. At dry conditions, the maximum proton conductivity was measured as 0.005 S/cm at 150°C for NafBN10, which is much higher than the pure Nafion. The results confirm that boron nitride nanoparticles have high contribution on the proton transfer, which may be explained with the formation of hydrogen bonds between amine and hydroxyl groups of boron nitride and sulfonic acid groups of Nafion. POLYM. COMPOS., 37:422–428, 2016. © 2014 Society of Plastics Engineers 相似文献
118.
Open porous polyester composites were prepared by the crosslinking of unsaturated polyester resin and divinylbenzene in water‐in‐oil concentrated emulsion templates with the presence of a conventional surface modified montmorillonite nanoclay. Medium and high internal phase emulsions with either 55 or 80 wt% of internal phase were used as templates. The effect of monomer composition, emulsifier concentration, and internal phase amount on the emulsion stability and the morphology of the resulting porous composites were investigated. Moreover, the morphological properties of the resulting composites were determined depending on the amount of nanoclay loading. It was found that the morphological features, namely surface area and cell diameter, were altered dramatically with the amount of nanoclay loading. An important part of the research was focused on the variation of mechanical and thermal properties with the incorporation of nanoclay particles. The mechanical properties were improved both with the nanoclay incorporation and the use of medium internal phase emulsions. However, the used nanoclay did not have a significant effect on the thermal stability of the resulting composites. POLYM. COMPOS., 37:1531–1538, 2016. © 2014 Society of Plastics Engineers 相似文献
119.
Bülent Akbas Ülgen Mert Tugsal F. İlknur Kara 《The Structural Design of Tall and Special Buildings》2009,18(4):405-426
In the energy‐based design approach, the seismic design is performed through the balancing of the energy input and the energy dissipation of the structure. The energy dissipation is represented by the hysteretic energy dissipation capacity defined as the total area enclosed in the force–deformation curves under cyclic loading. Thus, the energy‐based design approach considers the cumulative effect of the seismic loading of the structure. The cumulative damage in the structural members can be expressed in terms of cumulative plastic rotation (CPR). The CPR capacity plays an important role in determining the hysteretic energy dissipation capacity of a steel moment connection. This study investigated the energy response and the CPR capacity and demand through dynamic pushover analyses on steel moment‐resisting frames. The results were compared with the ones obtained from the pushover analysis. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
120.
The electrochemical syntheses of polypyrrole (PPy) and poly(pyrrole-co-o-anisidine) were achieved on 3102 aluminum alloy (Al) from 0.1 M monomer (pyrrole:o-anisidine, 8:2) containing 0.4 M oxalic acid solution using the cyclic voltammetry technique. The synthesized films were characterized by FT-IR spectroscopy. The thermal stability of films was determined by thermogravimetric analysis (TGA) technique. Surface morphologies were characterized by scanning electron microscope (SEM) images. The potential of zero charge (pzc) of Al was determined using electrochemical impedance spectroscopy (EIS). The corrosion behavior of samples was investigated with open circuit potential (Eocp)–time, EIS, and anodic polarization techniques. It was found that copolymer coated Al provides better barrier property against of corrosion in 3.5% NaCl solution. 相似文献