A knowledge-based geometry repair system for robust parametric CAD models

In modern multi-objective design optimization (MDO) an effective geometry engine is becoming an essential tool and its performance has a significant impact on the entire MDO process. Building a parametric geometry requires difficult compromises between the conflicting goals of robustness and flexibility. This article presents a method of improving the robustness of parametric geometry models by capturing and modeling engineering knowledge with a support vector regression surrogate, and deploying it automatically for the search of a more robust design alternative while trying to maintain the original design intent. Design engineers are given the opportunity to choose from a range of optimized designs that balance the ‘health’ of the repaired geometry and the original design intent. The prototype system is tested on a 2D intake design repair example and shows the potential to reduce the reliance on human design experts in the conceptual design phase and improve the stability of the optimization cycle. It also helps speed up the design process by reducing the time and computational power that could be wasted on flawed geometries or frequent human intervention

Totems

In modern multi-objective design optimization (MDO) an effective geometry engine is becoming an essential tool and its performance has a significant impact on the entire MDO process. Building a parametric geometry requires difficult compromises between the conflicting goals of robustness and flexibility. This article presents a method of improving the robustness of parametric geometry models by capturing and modeling engineering knowledge with a support vector regression surrogate, and deploying it automatically for the search of a more robust design alternative while trying to maintain the original design intent. Design engineers are given the opportunity to choose from a range of optimized designs that balance the ‘health’ of the repaired geometry and the original design intent. The prototype system is tested on a 2D intake design repair example and shows the potential to reduce the reliance on human design experts in the conceptual design phase and improve the stability of the optimization cycle. It also helps speed up the design process by reducing the time and computational power that could be wasted on flawed geometries or frequent human intervention

Can Performance of Indigenous Factors Influence Growth and Globalisation?"

This paper employs a total of thirty four openness factors and indigenous factors to construct two indicators for 62 world economies for the period 1998-2002. While most globalization studies concentrated on openness factors, regression estimates and simulation studies show that sound performance in indigenous factors are crucial to an economy’s growth and globalization. Empirical evidence shows that an optimal performance in indigenous factors can be identified, and that successful globalized economies are equipped with strong performance in their indigenous factors.Globalization; indigenous factors; openess; world economies

Dispersion strengthening in vanadium microalloyed steels processed by simulated thin slab casting and direct charging: Part I - Processing parameters, mechanical properties and microstructure

A study simulating thin slab continuous casting followed by direct charging into an equalisation furnace has been undertaken based on six low carbon (0.06wt-%) vanadium microalloyed steels. Mechanical and impact test data showed properties were similar or better than those obtained from similar microalloyed conventional thick cast as rolled slabs. The dispersion plus dislocation strengthening was estimated to be in the range 80-250MPa.A detailed TEM/EELS analysis of the dispersion sized sub-15nm particles showed that in all the steels, they were essentially nitrides with little crystalline carbon detected. In the Steels V-Nb, V-Ti and V-Nb-Ti, mixed transition metal nitrides were present. Modelling of equilibrium precipitates in these steels, based on a modified version of ChemSage, predicted that only vanadium rich nitrides would precipitate in austenite but that the C/N ratio would increase through the two phase field and in ferrite. The experimental analytical data clearly points to the thin slab direct charging process, which has substantially higher cooling rates than conventional casting, nucleating non-equilibrium particles in ferrite which are close to stoichiometric nitrides. These did not coarsen during the final stages of processing, but retained their highly stable average size of ~7nm resulting in substantial dispersion strengthening. The results are considered in conjunction with pertinent published literature

Мовна особистість Максима Рильського

Метою даної розвідки є спроба пізнання інтелектуального обширу мовної особистості Максима Рильського в контексті епохи

On the efficiency of estimating penetrating rank on large graphs

P-Rank (Penetrating Rank) has been suggested as a useful measure of structural similarity that takes account of both incoming and outgoing edges in ubiquitous networks. Existing work often utilizes memoization to compute P-Rank similarity in an iterative fashion, which requires cubic time in the worst case. Besides, previous methods mainly focus on the deterministic computation of P-Rank, but lack the probabilistic framework that scales well for large graphs. In this paper, we propose two efficient algorithms for computing P-Rank on large graphs. The first observation is that a large body of objects in a real graph usually share similar neighborhood structures. By merging such objects with an explicit low-rank factorization, we devise a deterministic algorithm to compute P-Rank in quadratic time. The second observation is that by converting the iterative form of P-Rank into a matrix power series form, we can leverage the random sampling approach to probabilistically compute P-Rank in linear time with provable accuracy guarantees. The empirical results on both real and synthetic datasets show that our approaches achieve high time efficiency with controlled error and outperform the baseline algorithms by at least one order of magnitude

Polydimethylsiloxane (PDMS)-based microfluidic channel with integrated commercial pressure sensors

The precise characterisation of boiling in microchannels is essential for the optimisation of applications requiring two phase cooling. In this paper polydimethylsiloxane (PDMS) is employed to make microchannels for characterising microboiling. In particular the material properties of PDMS facilitate rapid prototyping and its optical transparency provides the capability to directly view any fluid flow. The production of microchannels is complicated by the need to integrate custom made sensors. This paper presents a PDMS microfluidic device with integrated commercial pressure sensors, which have been used to perform a detailed characterisation of microboiling phenomena. The proposed approach of integrating commercial pressure sensors into the channel also has potential applications in a range of other microsystems

Slope stability analysis for cohesive materials filled on purely cohesive undrained clay

Stability charts for soil slopes were first produced by Taylor in 1937 and they continue to be used extensively as design tools and draw the attention of many investigators. From a review of literature, it was found that there is no convenient solution has been provided for cohesive materials filled on purely cohesive undrained clay. A recent study revealed that the embankment slope which has two-layered clays failed in an undrained state which shows the importance of this study. In order to obtain the solutions for this type of fill slope. A number of numerical method are employed, namely the finite element upper and lower bound limit analysis methods and limit equilibrium method. The numerical upper and lower bound limit analysis method can bracket true solutions within a small range (6%). The solutions of limit equilibrium analysis are used for comparison purpose

Using GIS and Multi-criteria Decision Analysis for Conflict Resolution in Land Use Planning

AbstractBased on the principles of sustainable development, land use planning often requires the compromise between economic development and environmental conservation while advocating social justice. Given that ideas, values, and attitudes vary among the stakeholders involved, land use planning inevitably incurs a variety of conflicts. The conflicts in land use planning can be described from the perspective of the conflicts among land use types and the conflicts among stakeholders. Accordingly, land use planning can be conceived as the process of dealing with conflicts among different land use types through resolving the conflicts among stakeholders. This study centers around two important issues in land use planning: land use allocation and specific land use proposal deliberation. A Conflict Resolution Framework was proposed based on GIS and Multi-criteria Decision Analysis techniques. A Consensus Building Model was established to address the conflicts among different stakeholders with competing interests in the process of land use allocation. A Spatial Conflict Resolution Strategy was developed to help stakeholders and planners formulate specific land use proposals through an iterative modification process. The both models were tested and evaluated in the context of Lantau, Island Hong Kong. Moreover, the challenges of this research and future work are also covered in this paper

Role of inertia in two-dimensional deformation and breakup of a droplet

We investigate by Lattice Boltzmann methods the effect of inertia on the deformation and break-up of a two-dimensional fluid droplet surrounded by fluid of equal viscosity (in a confined geometry) whose shear rate is increased very slowly. We give evidence that in two dimensions inertia is {\em necessary} for break-up, so that at zero Reynolds number the droplet deforms indefinitely without breaking. We identify two different routes to breakup via two-lobed and three-lobed structures respectively, and give evidence for a sharp transition between these routes as parameters are varied.Comment: 4 pages, 4 figure