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51.
N. Emrahoğlu İ. Yeğingil V. Peştemalci O. Şenkal H. M. Kandirmaz 《International journal of remote sensing》2013,34(4):649-655
In this study, a new classification algorithm in which only the selected pixels have been attempted to be classified (selected pixels classification: SPC) has been introduced and compared with the well known supervised classification methods such as maximum likelihood, minimum distance, nearest neighbour and condensed nearest neighbour. To examine the algorithm, Landsat Thematic Mapper (TM) data have been used to classify the crop cover in the selected region. It is clearly demonstrated that the SPC method has the higher accuracy with comparable CPU times. 相似文献
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Neural Computing and Applications - In this paper, we consider a system of nonlinear delay integro-differential equations with convolution kernels, which arises in biology. This problem... 相似文献
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Maikel Kishna Simona Negro Floortje Alkemade Marko Hekkert 《Industry and innovation》2017,24(3):263-279
This paper focuses on the strategies of incumbents that seek to develop discontinuous innovations within the boundaries of a mature innovation system. Mature innovation systems do not provide support for these discontinuous innovations. This article focuses on exploring why incumbents in these setting engage in discontinuous innovation and what strategies they deploy to become successful. We analyse 10 cases of incumbents developing discontinuous innovations in the mature Dutch greenhouse horticulture sector. The results of our analysis show that the incumbents are primarily triggered by dissatisfaction with the current way of doing business and that the existing institutions are the main barrier to discontinuous innovation. In response, the incumbents try to circumvent the existing innovation system in their innovation process, but when successful also engage in changing the existing innovation system. This paper contributes to the understanding of the role of incumbents as source of discontinuous innovation in mature innovation systems. 相似文献
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Investigating the effect of production process of ball mill refiner on some physical quality parameters of compound chocolate: response surface methodology approach 下载免费PDF全文
Omer Said Toker Fatma Tugce Zorlucan Nevzat Konar Orhan Dağlıoğlu Osman Sagdic Dilek Şener 《International Journal of Food Science & Technology》2017,52(3):788-799
Chocolate compound was produced using ball mill refiner, and the effect of agitator shaft speed and refining time on the physical quality parameters (particle size, colour and steady‐state rheology) of compound chocolate was determined using response surface methodology. The shaft speed and refining time range were selected between 40–60 r.p.m. and 10–30 min, respectively. Determination coefficient of the models established for particle size, Newtonian viscosity and colour parameters (brightness, chroma and hue angle) were found to be very close to unity. Increasing shaft speed and time induced a reduction in particle size and an increase in viscosity of the samples. Temperature sweep test was also performed, and the obtained data were successfully fitted to Arrhenius equation to calculate the corresponding parameters representing temperature dependency of the compounds. The results highlighted that the establishment of such models can provide essential information in terms of optimisation of production processes regarding usage purpose of the compound chocolate. 相似文献
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We report on an experimental study of the effects of interphase boundary anisotropy on eutectic microstructures using a new methodology called rotating directional solidification (RDS), which consists of rotating a thin sample with respect to a fixed unidirectional thermal gradient. The systems used are thin, large eutectic grains of the CBr4–C2Cl6 and In–In2Bi lamellar eutectic alloys. The shape of the observed RDS lamellar trajectories turns out to be a reproducible eutectic-grain-dependent feature, in agreement with the theoretical prediction that these trajectories are approximately homothetic to the Wulff form of the interphase boundary in the sample plane. We show that different modes of lamellar growth, ranging from quasi-isotropic to (crystallographically) locked, exist in different eutectic grains of the two alloys studied. A detailed characterisation of these modes is given, with particular attention to the as-yet poorly understood aspects of locked lamellar growth. 相似文献
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Davide Giglio Riccardo Minciardi Simona Sacone Silvia Siri 《Discrete Event Dynamic Systems》2014,24(3):339-352
A class of production systems are considered in this paper with the aim of determining closed-loop strategies providing the production effort as functions of the system state. The key feature of the considered class of systems is that the demand and the way it is satisfied are asynchronous sequences of part requests and instantaneous withdrawals, respectively, generated by discrete-event processes, whereas the production process has continuous-time dynamics. The optimization problem, whose objective is to minimize inventory and lateness costs, is restated as an optimal control problem by exploiting some structural properties of the optimal solution. Then, optimal closed-loop strategies are found with dynamic programming techniques. 相似文献