Kalibrace modelu pro optimalizaci systému vytápění a chlazení s akumulací energie do spodní vody

Building performance simulation (BPS) is a powerful tool to support building and system designers in emulating how orientation, building type, HVAC system etc. interacts the overall building performance. Currently BPS is used only for code compliance in the detailed design, neither to make informed choices between different design options nor for building and/ or system optimization [Wilde, 2004].BPS could/ should be used in a way of indicating design solutions, introducing an uncertainty and sensitivity analysis and building and/ or system optimization. This research is about enhancing the use of BPS in the detailed design by supporting design and system optimization

Free-energy functional for freezing transitions: Hard sphere systems freezing into crystalline and amorphous structures

A free-energy functional that contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the freezing of a system of hard spheres into crystalline and amorphous structures. The freezing parameters for fluid-crystal transition have been found to be in very good agreement with the results found from simulations. We considered amorphous structures found from the molecular dynamics simulations at packing fractions $\eta$ lower than the glass close packing fraction $\eta_{J}$ and investigated their stability compared to that of a homogeneous fluid. The existence of free-energy minimum corresponding to a density distribution of overlapping Gaussians centered around an amorphous lattice depicts the deeply supercooled state with a heterogeneous density profile

Combining point cloud and surface methods for modeling partial shading impacts of trees on urban solar irradiance

Although trees and urban vegetation have a significant influence on solar irradiation in the built environment, their impact on daylight and energy consumption is often not considered in building performance and urban environment simulation studies. This paper presents a novel method for comprehensive solar irradiance assessment that considers the dynamic partial shading impacts from trees. The proposed method takes urban point clouds as input and consists of three subsequent steps: (a) DGCNN-based segmentation, (b) fusion model generation, (c) matrix-based irradiance calculation. The method is validated by comparing model outputs with field measurement data, and an inter-model comparison with eleven state-of-the-art tree shading modeling approaches. Analyses carried out on daily and long-term basis show that the proposed fusion model can significantly reduce simulation errors compared to alternative approaches, while limiting the required input data to a minimum. The primary source of uncertainty stems from mismatches between tree morphology in the fusion model and reality, attributable to phenological growth and seasonal variations.</p

Project for the analysis of technology transfer Quarterly report, 1 Apr. 1969 - 30 Jun. 1969

Patterns, statistical analyses, and case studies of transfer and utilization of NASA generated technolog

Capability and deficiency of the simplified model for energy calculation of commercial buildings in the Brazilian regulation

This paper provides a preliminary assessment on the accuracy of the Brazilian regulation simplified model for commercial buildings. The first step was to compare its results with BESTEST. The study presents a straightforward approach to apply the BESTEST in other climates than the original one (Denver, Colorado, USA). The second step consisted on applying the simplified model for common buildings, and compare the results with those obtained using a state of the art building energy simulation (BES) program. Significant errors were found when comparing the simplified model with BESTEST and the common buildings analyzed

Modeling and identification of an RRR-robot

A dynamic model of a robot with 3 rotational degrees of freedom is derived in closed form. A systematic procedure for estimation of model dynamic parameters is suggested. It consists of the following steps: (i) identification of friction model parameters for each joint; (ii) calculation of optimal exciting trajectories, required for estimation of the remaining dynamic model parameters; (iii) estimation of these parameters using a least-squares method. The estimated model satisfactory reconstructs experimental control signals, justifying its use in model-based nonlinear control