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Research on the Structure Model and Mining Algorithm for Knowledge Discovery Based on Knowledge Base (KDK)

Yang Bingru,Shen Jiangtao,Chen Hongjie

Strategic Study of CAE 2003, Volume 5, Issue 6,   Pages 49-54

Abstract:

Knowledge discovery in knowledge base (KDK) is a brand-new task. Its success will directly act on the construction of large knowledge base, and, at present, it is important to the solving of the bottleneck of machine study—discovering knowledge. The main work of this paper is： The inductive structure of KDK based on the facts in knowledge base, and its algorithm and experimental verification; The inductive structure algorithm of KDK for the rules in knowledge base and its experimental verification.

Keywords： knowledge discovery based on knowledge base     induction logic of Carnap     induction logic of L. J.Cohen     evaluation of hypothesis    

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Measurement and correlation of supercritical CO

Hiroshi MACHIDA, Ryosuke TAGUCHI, Yoshiyuki SATO, Louw J. FLOURUSSE, Cor J. PETERS, Richard L. SMITH

Frontiers of Chemical Science and Engineering 2009, Volume 3, Issue 1,   Pages 12-19 doi: 10.1007/s11705-009-0151-3

Abstract: Ionicliquids combined with supercritical fluid technology hold great promise as working solvents for developing compact processes. Ionic liquids, which are organic molten salts, typically have extremely low volatility and high functionality, but possess high viscosities, surface tensions and low diffusion coefficients, which can limit their applicability. CO , on the other hand, especially in its supercritical state, is a green solvent that can be used advantageously when combined with the ionic liquid to provide viscosity and surface tension reduction and to promote mass transfer. The solubility of CO in the ionic liquid is key to estimating the important physical properties that include partition coefficients, viscosities, densities, interfacial tensions, thermal conductivities and heat capacities needed in contactor design. In this work, we examine a subset of available high pressure pure component ionic liquid PVT data and high pressure CO - ionic liquid solubility data and report new correlations for CO -ionic liquid systems with equations of state that have some industrial applications including: (1) general, (2) fuel desulfurization, (3) CO capture, and (4) chiral separation. New measurements of solubility data for the CO and 1-butyl-3-methylimidazolium octyl sulfate, [bmim][OcSO ] system are reported and correlated. In the correlation of the CO ionic liquid phase behavior, the Peng-Robinson and the Sanchez-Lacombe equations of state were considered and are compared. It is shown that excellent correlation of CO solubility can be obtained with either equation and they share some common characteristics regarding interaction parameters. In the Sanchez-Lacombe equation, parameters that are derived from the supercritical region were found to be important for obtaining good correlation of the CO -ionic liquid solubility data.

Keywords： compact processes     chiral ionic liquids     separations     thermodynamic properties     equations of state    

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Heat transfer and fluid flow analysis of an artificially roughened solar air heater: a CFD based investigation

Anil Singh YADAV,J. L. BHAGORIA

Frontiers in Energy 2014, Volume 8, Issue 2,   Pages 201-211 doi: 10.1007/s11708-014-0297-7

Abstract: In this paper, the effect of rib (circular sectioned) spacing on average Nusselt number and friction factor in an artificially roughened solar air heater (duct aspect ratio, AR= 5:1) is studied by adopting the computational fluid dynamics (CFD) approach. Numerical solutions are obtained using commercial software ANSYS FLUENT v12.1. The computations based on the finite volume method with the semi-implicit method for pressure-linked equations (SIMPLE) algorithm have been conducted. Circular sectioned transverse ribs are applied at the underside of the top of the duct, i.e., on the absorber plate. The rib-height-to-hydraulic diameter ratio ( ) is 0.042. The rib-pitch-to-rib-height ( ) ratios studied are 7.14, 10.71, 14.29 and 17.86. For each rib spacing simulations are executed at six different relevant Reynolds numbers from 3800 to 18000. The thermo-hydraulic performance parameter for = 10.71 is found to be the best for the investigated range of parameters at a Reynolds number of 15000.

Keywords： heat transfer     pressure drop     thermo-hydraulic performance parameter    

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Effects of fiber curvature on the microstructure of the interfacial transition zone in fresh concrete

CHEN Huisu, SUN Wei, ZHAO Qingxin, L. J. Sluys, P. Stroeven

Frontiers of Structural and Civil Engineering 2007, Volume 1, Issue 1,   Pages 99-106 doi: 10.1007/s11709-007-0010-6

Abstract: The study on the interfacial transition zone (ITZ) of concrete has received lots of attention in the last decade. However, no information is available on the influence of the curvature of a rigid surface on the microstructure of ITZ. This paper employed computer simulation technology to study the influence of fiber curvature on the initial microstructure of ITZ in concrete. For the sake of simplification, the investigation was first focused on the mono-size spherical particle packing system around a cylindrical fiber with different diameters. An algorithm of serial cylindrical sectioning was developed. The curve of the solid volume fraction versus the distance to the surface of the fiber was used as a parameter to characterize the microstructure of the ITZ. Then, the influence of the ratio of fiber diameter to particle diameter on the initial ITZ s microstructure was studied. These curves were compared with the ones from flat aggregate surface on which mono-size spherical particles were packed. Furthermore, the multi-size spherical particles system was further investigated. The simulation results demonstrate that no matter whether the spherical particles system is mono-size or multi-size, the fresh ITZ s microstructure is irrelevant to the curvature of the fiber. The shape of the curve of solid volume fraction versus the distance from the surface of the fiber is similar to that around a flat aggregate surface. In all cases, the horizontal coordinates of the first peak of the curves are located at around half the mean weight diameter of the particles. The thickness of ITZ reduces slightly with the decrease in water/cement ratio. Therefore, one may use the ITZ s microstructure around a flat aggregate surface to represent the ITZ s microstructure around a cylindrical fiber in the fresh state, and vice versa.

Keywords： diameter     initial microstructure     influence     surface     spherical particle    

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A regularization scheme for explicit level-set XFEM topology optimization

Markus J. GEISS, Jorge L. BARRERA, Narasimha BODDETI, Kurt MAUTE

Frontiers of Mechanical Engineering 2019, Volume 14, Issue 2,   Pages 153-170 doi: 10.1007/s11465-019-0533-2

Abstract: Regularization of the level-set (LS) field is a critical part of LS-based topology optimization (TO) approaches. Traditionally this is achieved by advancing the LS field through the solution of a Hamilton-Jacobi equation combined with a reinitialization scheme. This approach, however, may limit the maximum step size and introduces discontinuities in the design process. Alternatively, energy functionals and intermediate LS value penalizations have been proposed. This paper introduces a novel LS regularization approach based on a signed distance field (SDF) which is applicable to explicit LS-based TO. The SDF is obtained using the heat method (HM) and is reconstructed for every design in the optimization process. The governing equations of the HM, as well as the ones describing the physical response of the system of interest, are discretized by the extended finite element method (XFEM). Numerical examples for problems modeled by linear elasticity, nonlinear hyperelasticity and the incompressible Navier-Stokes equations in two and three dimensions are presented to show the applicability of the proposed scheme to a broad range of design optimization problems.

Keywords： level-set regularization     explicit level-sets     XFEM     CutFEM     topology optimization     heat method     signed distance field     nonlinear structural mechanics     fluid mechanics    

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A perspective on the promoting effect of Ir and Au on Pd toward the ethanol oxidation reaction in alkaline media

WEI, L. X. LUO, F. LI, J. L. ZHANG

Frontiers in Energy 2018, Volume 12, Issue 4,   Pages 501-508 doi: 10.1007/s11708-018-0586-7

Abstract: There remain great challenges in developing highly efficient electrocatalysts with both high activity and good stability for the ethanol oxidation reaction in alkaline media. Herein, two architectures of tri-metallic PdIrAu/C electrocatalysts are designed and the promoting effect of Au and Ir on Pd toward the ethanol oxidation reaction (EOR) in alkaline media is investigated in detail. On the one hand, the tri-metallic Pd Au Ir/C electrocatalyst with a solid solution alloy architecture is less active relative to Pd Ir/C and Pd/C while the stabilizing effect of Au leads to both a higher activity and a lower degradation percentage after 3000 cycles of the accelerated degradation test (ADT) on Pd Au Ir/C than those on Pd Ir/C. On the other hand, the tri-metallic Pd Ir@(1/3Au)/C electrocatalyst with a near surface alloy architecture delivers a much higher activity with an improvement up to 50.4% compared to Pd Ir/C. It is speculated that for the tri-metallic Pd Ir@(1/3Au)/C electrocatalyst, certain Au atoms are well designed on surfaces to introduce an electronic modification, thus leading to an anti-poisoning effect and improving the EOR activity.

Keywords： fuel cells     catalysts     ethanol oxidation     alkaline media     solid solution alloy     near surface alloy    

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Seismic performance of composite moment-resisting frames achieved with sustainable CFST members

JIANG,L. MACEDO,J. M. CASTRO,R. MONTEIRO,N. SILVESTRE

Frontiers of Structural and Civil Engineering 2016, Volume 10, Issue 3,   Pages 312-332 doi: 10.1007/s11709-016-0345-y

Abstract: The main objective of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube (CFST) columns made with Rubberized Concrete (RuC), and to assess the seismic performance of moment-resisting frames with these structural members. The paper describes an experimental campaign where a total of 36 specimens were tested, resorting to a novel testing setup, aimed at reducing both the preparation time and cost of the test specimens. Different geometrical and material parameters were considered, namely cross-section type, cross-section slenderness, aggregate replacement ratio, axial load level and lateral loading type. The members were tested under both monotonic and cyclic lateral loading, with different levels of applied axial loading. The test results show that the bending behaviour of CFST elements is highly dependent on the steel tube properties and that the type of infill does not have a significant influence on the flexural behaviour of the member. It is also found that Eurocode 4 is conservative in predicting the flexural capacity of the tested specimens. Additionally, it was found that the seismic design of composite moment-resisting frames with CFST columns, according to Eurocode 8, not only leads to lighter design solutions but also to enhanced seismic performance in comparison to steel frames.

Keywords： concrete filled steel tubes     rubberized concrete     composite frames     seismic performance assessment    

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Modeling process-structure-property relationships for additive manufacturing

Wentao YAN, Stephen LIN, Orion L.KAFKA, Cheng YU, Zeliang LIU, Yanping LIAN, Sarah WOLFF, Jian CAO, Gregory J. WAGNER, Wing Kam LIU

Frontiers of Mechanical Engineering 2018, Volume 13, Issue 4,   Pages 482-492 doi: 10.1007/s11465-018-0505-y

Abstract:

This paper presents our latest work on comprehensive modeling of process-structure-property relationships for additive manufacturing (AM) materials, including using data-mining techniques to close the cycle of design-predict-optimize. To illustrate the process-structure relationship, the multi-scale multi-physics process modeling starts from the micro-scale to establish a mechanistic heat source model, to the meso-scale models of individual powder particle evolution, and finally to the macro-scale model to simulate the fabrication process of a complex product. To link structure and properties, a high-efficiency mechanistic model, self-consistent clustering analyses, is developed to capture a variety of material response. The model incorporates factors such as voids, phase composition, inclusions, and grain structures, which are the differentiating features of AM metals. Furthermore, we propose data-mining as an effective solution for novel rapid design and optimization, which is motivated by the numerous influencing factors in the AM process. We believe this paper will provide a roadmap to advance AM fundamental understanding and guide the monitoring and advanced diagnostics of AM processing.

Keywords： additive manufacturing     thermal fluid flow     data mining     material modeling    

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Data-Driven Microstructure and Microhardness Design in Additive Manufacturing Using a Self-Organizing Map Article

Zhengtao Gan, Hengyang Li, Sarah J. Wolff, Jennifer L. Bennett, Gregory Hyatt, Gregory J.

Engineering 2019, Volume 5, Issue 4,   Pages 730-735 doi: 10.1016/j.eng.2019.03.014

Abstract:

To design microstructure and microhardness in the additive manufacturing (AM) of nickel (Ni)-based superalloys, the present work develops a novel data-driven approach that combines physics-based models, experimental measurements, and a data-mining method. The simulation is based on a computational thermal-fluid dynamics (CtFD) model, which can obtain thermal behavior, solidification parameters such as cooling rate, and the dilution of solidified clad. Based on the computed thermal information, dendrite arm spacing and microhardness are estimated using well-tested mechanistic models. Experimental microstructure and microhardness are determined and compared with the simulated values for validation. To visualize process–structure–properties (PSP) linkages, the simulation and experimental datasets are input to a data-mining model—a self-organizing map (SOM). The design windows of the process parameters under multiple objectives can be obtained from the visualized maps. The proposed approaches can be utilized in AM and other data-intensive processes. Data-driven linkages between process, structure, and properties have the potential to benefit online process monitoring control in order to derive an ideal microstructure and mechanical properties.

Keywords： Additive manufacturing     Data science     Multiphysics modeling     Self-organizing map     Microstructure     Microhardness     Ni-based superalloy    

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REINTEGRATION OF CROP-LIVESTOCK SYSTEMS IN EUROPE: AN OVERVIEW

J. VAN DE VEN, Davey L. JONES, David R. CHADWICK

Frontiers of Agricultural Science and Engineering 2021, Volume 8, Issue 1,   Pages 111-129 doi: 10.15302/J-FASE-2020373

Abstract: Ongoing specialization of crop and livestock systems provides socioeconomic benefits to the farmer but has led to greater externalization of environmental costs when compared to mixed farming systems. Better integration of crop and livestock systems offers great potential to rebalance the economic and environmental trade-offs in both systems. The aims of this study were to analyze changes in farm structure and review and evaluate the potential for reintegrating specialized intensive crop and livestock systems, with specific emphasis on identifying the co-benefits and barriers to reintegration. Historically, animals were essential to recycle nutrients in the farming system but this became less important with the availability of synthetic fertilisers. Although mixed farm systems can be economically attractive, benefits of scale combined with socio-economic factors have resulted in on-farm and regional specialization with negative environmental impacts. Reintegration is therefore needed to reduce nutrient surpluses at farm, regional and national levels, and to improve soil quality in intensive cropping systems. Reintegration offers practical and cost-effective options to widen crop rotations and promotes the use of organic inputs and associated benefits, reducing dependency on synthetic fertilisers, biocides and manure processing costs. Circular agriculture goes beyond manure management and requires adaptation of both food production and consumption patterns, matching local capacity to produce with food demand. Consequently, feed transport, greenhouse gas emissions, nutrient surpluses and nutrient losses to the environment can be reduced. It is concluded that reintegration of specialized farms within a region can provide benefits to farmers but may also lead to further intensification of land use. New approaches within a food system context offer alternatives for reintegration, but require strong policy incentives which show clear, tangible and lasting benefits for farmers, the environment and the wider community.

Keywords： circular agriculture     coupled farming systems     mixed farming     specialised farming systems     GHG    

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Determination of selected semi-volatile organic compounds in water using automated online solid-phase extraction with large-volume injection/gas chromatography/mass spectrometry

Yongtao LI, Christina L. MCCARTY, Ed J. GEORGE

Frontiers of Environmental Science & Engineering 2011, Volume 5, Issue 3,   Pages 417-425 doi: 10.1007/s11783-011-0310-x

Abstract: For a sample volume of 10 mL, the linear calibrations ranged from 0.01 or 0.05 to 2.5μg·L , and the methoddetection limits were less than 0.1μg·L .For the reagent water samples fortified at 1.0μg·L and 2.0?μg·L , the obtained mean absolute recoveries were 70%–130% with relative standard deviations of lessFor the drinking water, groundwater, and surface water samples fortified at 1.0μg·L , the obtained mean

Keywords： automated solid-phase extraction     programmed-temperature vaporization     large-volume injection     gas chromatography/mass spectrometry     semi-volatile organic compounds     water analysis    

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Purification of

PIETZSCH, J. ULRICH

Frontiers of Chemical Science and Engineering 2013, Volume 7, Issue 1,   Pages 37-42 doi: 10.1007/s11705-013-1303-z

Abstract: All crystallizations were performed in tris-acetate buffer (50 mmol·L , pH 5.1).

Keywords： protein crystallization     L-asparaginase II     purification    

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Plated contacts for solar cells with superior adhesion strength to screen printed solar cells

YOUNG,J. JI,M. EDWARDS,A. SUGIANTO,L. MAI,S. WENHAM,C. CHONG

Frontiers in Energy 2017, Volume 11, Issue 1,   Pages 72-77 doi: 10.1007/s11708-016-0428-4

Abstract: The improvement of adhesion strength and durability of plated contacts is required for cell manufacturers to gain confidence for large-scale manufacturing. To overcome weak adhesion at the metal/Si interface, new approaches were developed. These involve the formation of laser-ablated anchor points, or grooves in the extreme case of overlapping anchor points, in the heavily doped silicon surface. When plated, these features greatly strengthen the mechanical adhesion strength of the metal. A stylus-based adhesion tester was developed specifically for evaluating the effectiveness of plated contacts to smooth silicon surfaces. The use of such a tester was also extended in this work to textured and roughened surfaces to allow evaluation of different metal contacting approaches. The adhesion strengths for various metal contacting schemes were evaluated, including screen-printed silver contacts, nickel/copper (Ni/Cu) light-induced plated (LIP) contacts for laser-doped selective emitter (LDSE) cells, buried-contact solar cells (BCSCs), and Ni/Cu LIP contacts formed with laser-ablated anchoring points in selective emitter (LAASE) cells. The latter has superior adhesion strength. The standard “peel test” of the industry was compared to the stylus-based adhesion testing, with the latter shown value for testing metal contacts on smooth surfaces but with caution needed for use with textured or roughened surfaces.

Keywords： light-induced plating     metal adhesion strength     copper plating     metal contacts     solar cell durability     silicon solar cells    

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Application of fuzzy logic control algorithm as stator power controller of a grid-connected doubly-fedinduction generator

Ridha CHEIKH, Arezki MENACER, Said DRID, Mourad TIAR

Frontiers in Energy 2013, Volume 7, Issue 1,   Pages 49-55 doi: 10.1007/s11708-012-0217-7

Abstract: This paper discusses the power outputs control of a grid-connected doubly-fed induction generator (DFIGstrictly controlled at a required level, which, in this paper, is realized with an optimized fuzzy logic

Keywords： doubly-fed induction generator (DFIG)     vector control     fuzzy logic controller     optimization     power factor    

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Impact of Low-Impact Development Technologies from an Ecological Perspective in Different Residential Zones of the City of Atlanta, Georgia Article

Cohen, Marc J. Weissburg, Bert Bras

Engineering 2018, Volume 4, Issue 2,   Pages 194-199 doi: 10.1016/j.eng.2018.03.005

Abstract:

Low-impact development (LID) technologies have a great potential to reduce water usage and stormwater runoff and are therefore seen as sustainable improvements that can be made to traditional water infrastructure. These technologies include bioretention areas, rainwater capturing, and xeriscaping, all of which can be used in residential zones. Within the City of Atlanta, residential water usage accounts for 53% of the total water consumption; therefore, residential zones offer significant impact potential for the implementation of LID. This study analyzes the use of LID strategies within the different residential zones of the City of Atlanta from an ecological perspective by drawing analogies to natural ecosystems. The analysis shows that these technologies, especially with the addition of a graywater system, work to improve the conventional residential water network based upon these ecological metrics. The higher metric values suggest greater parity with healthy, natural ecosystems.

Keywords： Low-impact development     Ecological network analysis     Residential water consumption    

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Title Author Date Type Operation

Research on the Structure Model and Mining Algorithm for Knowledge Discovery Based on Knowledge Base (KDK)

Yang Bingru,Shen Jiangtao,Chen Hongjie

Journal Article

Measurement and correlation of supercritical CO

Hiroshi MACHIDA, Ryosuke TAGUCHI, Yoshiyuki SATO, Louw J. FLOURUSSE, Cor J. PETERS, Richard L. SMITH

Journal Article

Heat transfer and fluid flow analysis of an artificially roughened solar air heater: a CFD based investigation

Anil Singh YADAV,J. L. BHAGORIA

Journal Article

Effects of fiber curvature on the microstructure of the interfacial transition zone in fresh concrete

CHEN Huisu, SUN Wei, ZHAO Qingxin, L. J. Sluys, P. Stroeven

Journal Article

A regularization scheme for explicit level-set XFEM topology optimization

Markus J. GEISS, Jorge L. BARRERA, Narasimha BODDETI, Kurt MAUTE

Journal Article

A perspective on the promoting effect of Ir and Au on Pd toward the ethanol oxidation reaction in alkaline media

WEI, L. X. LUO, F. LI, J. L. ZHANG

Journal Article

Seismic performance of composite moment-resisting frames achieved with sustainable CFST members

JIANG,L. MACEDO,J. M. CASTRO,R. MONTEIRO,N. SILVESTRE

Journal Article

Modeling process-structure-property relationships for additive manufacturing

Wentao YAN, Stephen LIN, Orion L.KAFKA, Cheng YU, Zeliang LIU, Yanping LIAN, Sarah WOLFF, Jian CAO, Gregory J. WAGNER, Wing Kam LIU

Journal Article

Data-Driven Microstructure and Microhardness Design in Additive Manufacturing Using a Self-Organizing Map

Zhengtao Gan, Hengyang Li, Sarah J. Wolff, Jennifer L. Bennett, Gregory Hyatt, Gregory J.

Journal Article

REINTEGRATION OF CROP-LIVESTOCK SYSTEMS IN EUROPE: AN OVERVIEW

J. VAN DE VEN, Davey L. JONES, David R. CHADWICK

Journal Article

Determination of selected semi-volatile organic compounds in water using automated online solid-phase extraction with large-volume injection/gas chromatography/mass spectrometry

Yongtao LI, Christina L. MCCARTY, Ed J. GEORGE

Journal Article

Purification of

PIETZSCH, J. ULRICH

Journal Article

Plated contacts for solar cells with superior adhesion strength to screen printed solar cells

YOUNG,J. JI,M. EDWARDS,A. SUGIANTO,L. MAI,S. WENHAM,C. CHONG

Journal Article

Application of fuzzy logic control algorithm as stator power controller of a grid-connected doubly-fedinduction generator

Ridha CHEIKH, Arezki MENACER, Said DRID, Mourad TIAR

Journal Article

Impact of Low-Impact Development Technologies from an Ecological Perspective in Different Residential Zones of the City of Atlanta, Georgia

Cohen, Marc J. Weissburg, Bert Bras

Journal Article