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1.
Methodology of Programmable Process Structures has been implemented and applied for the flexible automatic generation and simulation of Recirculating Aquaculture Systems. First, we implemented and validated the model for a pilot unit, based on short time experiments with Common carp (Cyprinus carpio), utilizing data and functionalities from the literature. Afterwards, starting from this model we generated a hypothetical single tank model of simulated increasing volume, to demonstrate how it supports the simplified, preliminary analysis, design and control of the possible multi-stage systems. We showed that the simulation of a single tank with an appropriately increasing volume makes possible to study the various control strategies, as well as to design the structure and the grading strategy of the multi-stage systems, without an increased combinatorial complexity. In the knowledge of the simulated increasing volume, we determined the volumes of subsequent stages by equidistant partitioning of the rearing time, algorithmically. Considering the available (or planned) tank volumes, this method makes possible to design a multi-stage system that approximately corresponds to the previously optimized single tank model. This conclusion was illustrated by the generation and simulation of the model for the respective multi-stage system. 相似文献
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随机路面谱的计算机模拟 总被引:7,自引:3,他引:7
在正弦波叠加模型的基础上进行了随机路面谱的计算机模拟。从空间路面频率谱出发给出了模拟随机路面谱的方法。利用Matlab软件编制了生成任意等级三维随机路面谱的程序。最后结合多体动力学仿真软件ADAMS的虚拟样机技术对生成的随机路面谱进行了分析和讨论。结果表明,该随机路面谱的计算机模拟能够更便捷的结合相关的软件进行汽车性能的分析和评价。 相似文献
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一种车辆平顺性虚拟试验方法 总被引:3,自引:0,他引:3
探讨了一种车辆平顺性虚拟试验的方法 :利用 Multi Gen Creator工具对二维和三维图形进行绘制编辑 ,形成虚拟试验场的三维图形数据库 ,然后由 Open GVS SDK通过调用图形数据库及对 Open GVS中通道、场景、光照、相机等资源的编程 ,建立了模拟真实环境的虚拟道路试验场。研究表明 ,用 Open GVS SDK软件建立的虚拟试验场环境逼真 ,拟实效果好。在用鼠标、键盘等外部输入工具进行场景控制时 ,响应快、实时性好。该技术与虚拟样机技术相结合 ,可以在计算机上实现车辆的性能试验 相似文献
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陶瓷烧结过程显微组织演化的模型化与模拟 总被引:1,自引:0,他引:1
用一种改进的Monte Carlo potts模型二维模拟了陶瓷烧结过程中显微组织的演化,在改进模型中使用了Tikare等提出的空位湮灭算法来模拟致密化过程。结果表明,改进的Monte Carlo ports模型可以模拟固相和空位的扩散过程,很好地再现了陶瓷烧结过程中显微组织的演化和致密化过程。同时研究了晶界迁移率和空位湮灭概率对烧结致密化过程的影响。 相似文献
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Céline Leroy Sylvie Sabatier Novi Sari Wahyuni Jean-François Barczi Jean Dauzat Marilyne Laurans Daniel Auclair 《Agroforestry Systems》2009,77(1):37-47
In agroforestry systems, the distribution of light transmitted under tree canopies can be a limiting factor for the development
of intercrops. The light available for intercrops depends on the quantity of light intercepted by tree canopies and, consequently,
on the architecture of the tree species present. The influence of tree architecture on light transmission was analysed using
dynamic 3D architectural models. The architectural analysis of Acacia mangium and Tectona grandis was performed in Indonesian agroforestry systems with trees aged from 1 to 3 years. 3D virtual trees were then generated
with the AmapSim simulation software and 3D virtual experiments in which tree age, planting density, planting pattern and
pruning intensity varied were reconstructed in order to simulate light available for the crop. Canopy closure of trees was
more rapid in A. mangium than in T. grandis agroforestry systems; after 3 years the quantity of light available for A. mangium intercrops was three times lower than under T. grandis. Simulations with A. mangium showed that practices such as pruning and widening tree spacing enable to increase the total transmitted light within the
stand. On T. grandis, modification of the tree row azimuth resulted in changes in the spatial and seasonal distribution of light available for
the intercrops. These results are discussed in terms of agroforestry system management.
相似文献
Sylvie SabatierEmail: |
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Withthesmallsawlogwidespreadused,theuncut-boardsandslabsarecutbythemulti-bitrippingedgerinthejhoberindustw.AfersawingripPed,theunedgedboedaccuratelyvolumeisfAnotherparametCrsaredefinitebyadrawing,theaPProimatevolumeforn1ulateofunedgedboardistx,y,~inatC,x'… 相似文献
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This study focuses on the problem of irregular diameter structure in a silver fir–beech selection (plenter) forest with a “surplus” of large diameter trees and a lack of natural regeneration and small diameter trees. We sampled 274 plots (900 m2 each) in the Belevine research site (266.24 ha) in the mountain region Gorski Kotar (Croatia), where diameter (dbh) distribution, diameter increment, and natural regeneration were analyzed in detail. A low density of natural regeneration, weak annual recruitment of small (10 cm dbh) diameter trees (only five trees per hectare), delayed diameter growth of trees, and a low annual rate of trees reaching the next dbh class were attributed to the current irregular dbh structure. The stand development prediction for the next 50 years is based on a simulation model, which considers the current diameter structure, increment, recruitment, and future cutting regime. Intensive cutting in the first of five 10-year cutting cycles (intensity higher of 25%) is needed to initiate natural regeneration and to accelerate growth of young silver fir trees. In the next 50 years, the irregular diameter structure will be gradually improved. 相似文献