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91.
Trend Assessment by the Innovative-Şen Method 总被引:1,自引:0,他引:1
İsmail Dabanlı Zekai Şen Mehmet Öner Yeleğen Eyüp Şişman Bülent Selek Yavuz Selim Güçlü 《Water Resources Management》2016,30(14):5193-5203
Hydro-meteorological time series may include trend components mostly due to climate change since about three to four decades. Trend detection and identification in a better and refined manner are among the major current research topics in water resources domain. Even though different methodologies can be found for trend detection in literature, two well-known procedures are the Mann-Kendall (MK) trend test and recently innovative-?en trend method, which provides different aspects of the trend. The theoretical basis and application of these two methods are completely different. The MK test gives a holistic monotonic trend without any categorization of the time series into a set of clusters, but the innovative-?en method is based on cluster and provides categorical trend behavior in a given time series. The main purpose of this paper is to provide important differences between these two approaches and their possible similarities. The applications of the two approaches are given for hydro-meteorological records including relative humidity, temperature, precipitation and runoff from Ergene drainage basin in the north-western part of Turkey. It is observed that although MK trend test does not show significant trend almost in all the cases, the innovative-?en approach yields trend categorizations as “very low”, “low”, “medium” “high” and “very high”, which should be taken into consideration in future flood (“very high”) and drought (“very low”) studies. 相似文献
92.
Kurtulus Kullu Uğur Güdükbay Dinesh Manocha 《Autonomous Agents and Multi-Agent Systems》2017,31(6):1403-1423
Behavioral plausibility is one of the major aims of crowd simulation research. We present a novel approach that simulates communication between the agents and assess its influence on overall crowd behavior. Our formulation uses a communication model that tends to simulate human-like communication capability. The underlying formulation is based on a message structure that corresponds to a simplified version of Foundation for Intelligent Physical Agents Agent Communication Language Message Structure Specification. Our algorithm distinguishes between low- and high-level communication tasks so that ACMICS can be easily extended and employed in new simulation scenarios. We highlight the performance of our communication model on different crowd simulation scenarios. We also extend our approach to model evacuation behavior in unknown environments. Overall, our communication model has a small runtime overhead and can be used for interactive simulation with tens or hundreds of agents. 相似文献
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Betül Sen Sultan Kuzu Enes Demir Tuğba Önal Fatih Şen 《International Journal of Hydrogen Energy》2021,46(24):13510-13514
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Kilicaslan M. Fatih Altaib Salaheddin Salem Vurdu Can Doğan 《Metals and Materials International》2019,25(6):1457-1466
Metals and Materials International - In this project the morphology and microstructure of both conventional cast and melt spun of Al–20Si–9Fe–1.2Nb and... 相似文献
96.
Zarife Sibel Şahin Mehmet Demir Tuğrul Yıldırım Ömer Yurdakul Dursun Ali Köse 《International Journal of Hydrogen Energy》2021,46(54):27631-27642
Four novel metal organic framework (MOF) structures containing acesulfame (ace) and 1,10-phenanthroline (phen) ligands of Co2+, Ni2+, Cu2+ and Zn2+ metal cations were synthesized. The crystal structure analysis of three compounds (1, 2, and 3) was also performed. The structural formula for complex 4 is proposed based on spectroscopic and thermal analysis data. It has been determined that structures 1, 2, and 4 are in a distorted octahedral geometry. It has been suggested that the charge balance of the coordination sphere with 2+ is provided by two monoanionic ace ligands located outside the coordination sphere as counter-ion. In structure 3, there are two CuII metal cations, two phen ligands coordinated as bidentate to each metal cation and ace ligand that provides monoanionic-monodentate coordination. The Cu2+ cation has distorted bipyramidal geometry. The maximum hydrogen gas adsorption has been found 1.4575 mL/g (0.046 wt%) for the Ni complex. 相似文献
97.
Polycrystalline samples of Y0.6Gd0.4Ba2?x Nb x Cu3O7?δ and Y0.6Gd0.4Ba2Cu3?x Nb x O7?δ with different Nb contents (x=0.025, 0.075, 0.125, 0.175 and 0.225) were prepared using the solid state reaction method. Structural and electrical properties of new compounds were investigated with optical microscope, scanning electron microscopy (SEM), X-ray diffraction (XRD), Four Point Probe (FPP). The results indicated that Nb constituted YBa2NbO6 structure instead of substituting to the Y0.6Gd0.4Ba2Cu3O7?δ structure. YBa2NbO6 structures gathered between grains. Transition temperature did not change significantly, but critical current (J c) values decreased with increase of Nb concentration. The underlying reason is that the oxygen concentration of compounds remained unchanged due to Gd; thus, T c values did not change significantly. 相似文献
98.
We present a semiempirical theory of the effects of an orientation dependence of the surface free energy of interphase boundaries (interphase boundary anisotropy) on lamellar eutectic growth in thin samples. We show that, to a good approximation, thin lamellar eutectic patterns with a strong interphase boundary anisotropy travel along the growth front at such a velocity – or, equivalently, at such an inclination angle of the lamellae left behind in the solid – that the surface tension force of the interphase boundary is nearly parallel to the applied thermal gradient. This explains, among other things, the crystallographic locking of lamellar eutectic patterns that occurs in those eutectic grains, which have cusp singularities in the Wulff plot of the interphase boundary. Based on this theory, we show that the rotating directional solidification method, by which a thin sample is rotated with respect to a fixed unidirectional thermal gradient, must yield eutectic lamellae whose trajectories are nearly homothetic to the two-dimensional Wulff form of the interphase boundary. This opens up new possibilities for the experimental study of interphase boundary anisotropy in eutectic alloys. 相似文献
99.
Adil Baykasoğlu Zeynep D. U. Durmuşoğlu 《The International Journal of Advanced Manufacturing Technology》2012,58(5-8):693-707
It has been essential to include flexibility in manufacturing policy making since variability in demand and products are considerably increasing. However, it is important to know and to monitor the proper level and type of flexibility that is required to obtain full benefits from it. This paper analyses the effects of flexibility on flow time performance of a simulated job shop. For that purpose, several scenarios are developed under four flexibility levels with two different machine selection rule and three types of dispatching rules. Furthermore, effect of jockeying as a queuing policy on the flow time performance is also investigated through simulation modeling. Results indicated that full flexibility is a preferable state for most of the cases. However, in some cases, chain configurations perform similar results since it combines the benefits of pooling and specialization. In addition, it is observed that a queue control mechanism like jockeying is an effective way to improve performance even though it may increase complexity of controlling policy. 相似文献
100.