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See detailExperimental alternatives in inducing systems of behavior classifications from everyday language
Krolak-Schwerdt, Sabine UL

in International Journal of Small Group Research (1987), 3

Detailed reference viewed: 14 (1 UL)
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See detailExperimental analysis of eGLOSA and eGLODTA transit control strategies
Giorgione, Giulio UL; Viti, Francesco UL; Rinaldi, Marco UL et al

in Proceedings of the 5th IEEE International Conference on Models and Technologies for Intelligent Transportation Systems, MT-ITS 2017 (2017)

Battery powered electric buses have higher energy efficiency, lower emissions and noise when compared to buses with internal combustion engines. However, due to battery charging requirements, their large ... [more ▼]

Battery powered electric buses have higher energy efficiency, lower emissions and noise when compared to buses with internal combustion engines. However, due to battery charging requirements, their large-scale integration into public transport operations is more complex. This study proposes a novel concept supporting said integration via new control strategies, dubbed e-GLOSA and e-GLODTA. These strategies extend the existing Green Light Optimal Speed and Dwell Time Systems (GLOSA/GLODTA) to account for the specific needs of electric buses. That is, they include the goals of minimizing the energy consumption between charging stations, and maximizing available charging time. At the same time, interference with schedule requirements is minimized. The formulated heuristics are tested on a Bus Rapid Transit (BRT) corridor case study, where different scenarios—such as placement of charging stations and bus regularity—are studied to assess under which conditions each action (maintain speed, accelerate or dwell for a longer time at a stop) is beneficial. Results show that eGLOSA contributes to schedule adherence while eGLODTA allows satisfying charging time constraints. [less ▲]

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See detailAn Experimental Analysis of Fraud Detection Methods in Enterprise Telecommunication Data using Unsupervised Outlier Ensembles
Kaiafas, Georgios UL; Hammerschmidt, Christian UL; Lagraa, Sofiane UL et al

in Kaiafas, Georgios; Hammerschmidt, Christian; State, Radu (Eds.) 16th IFIP/IEEE Symposium on Integrated Network and Service Management (IM 2019) (2019)

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See detailAn Experimental Analysis of Optimal Renewable Resource Management:The Fishery
Neugebauer, Tibor UL; Hey, John D; Sadrieh, Abdolkarim

E-print/Working paper (2008)

Detailed reference viewed: 63 (1 UL)
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See detailExperimental and analytical analysis of the load-bearing capacity Pu of improved dry-stacked masonry
Chewe Ngapeya, Gelen Gael UL; Waldmann, Danièle UL

in Journal of Building Engineering (2020), 27

Dry-Stacked Masonry (DSM) as structural load-bearing element is still unexploited because of many factors including the early face-shell cracking, the impacts of the block imperfections on the wall load ... [more ▼]

Dry-Stacked Masonry (DSM) as structural load-bearing element is still unexploited because of many factors including the early face-shell cracking, the impacts of the block imperfections on the wall load-bearing capacity (Pu) and the lack of design code safely predicting Pu. Through experimental tests, this paper investigates a strategy for improving Pu of DSM by placing an additional horizontal contact layer on the top face of raw DSM blocks. The effect of four mixtures used to improve the raw DSM blocks has been investigated. Further, a mathematical model predicting Pu is proposed which takes into account the effects of the block imperfections. In the course of the investigation, 20 DSM wallets and 25 DSM prisms built with raw and improved DSM blocks were tested to failure under axial compression. In the former, the face-shell cracking load (Pcrack) and the load-bearing capacity (Pu) were recorded, while in the latter, the actual contact area was recorded in hundred full bed-joints using Prescale Fujifilm strips. The results showed that a contact layer of well-defined properties increased the actual contact area from 23% to 55% and improved Pu by 31,9%. The mathematical model for the raw DSM blocks predicts Pu with a mean accuracy of 93% and a standard deviation of 12% where the standards EN 1996-1-1 for mortared masonry exhibited a mean accuracy of 137% and a standard deviation of about 29%. Concerning the improved DSM blocks, the proposed model predicts Pu with a mean accuracy of 106% and a standard deviation of 10%, whereas the standards EN 1996-1-1 presents a mean accuracy of 124% and a standard deviation of 9%. [less ▲]

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See detailAn experimental and computational study of laminated paperboard creasing and folding
Beex, Lars UL; Ron, Peerlings

in International Journal of Solids and Structures (2009)

Laminated paperboard is often used as a packaging material for products such as toys, tea and frozenfoods. To make the paperboard packages appealing for consumers, the fold lines must be both neat and ... [more ▼]

Laminated paperboard is often used as a packaging material for products such as toys, tea and frozenfoods. To make the paperboard packages appealing for consumers, the fold lines must be both neat and undamaged. The quality of the folds depends on two converting processes: the manufacture of fold lines (creasing) and the subsequent folding. A good crease contains some delamination, initiated during creasing, to reduce the bending stiffness and to prevent the board from breaking during folding. However, for boards of high grammage breaking of the top layer is nevertheless a frequent problem. The mechanisms that operate in the creasing zone during creasing and folding, and that may thus result in breaking of the top layer, are studied in this contribution on the basis of idealized small-scale creasing and folding experiments. However, since experimental observations are only limited means to study the paperboard’s behavior, a mechanical model is proposed to obtain more detailed insight. Although the material and delamination descriptions used in the mechanical model are both relatively straightforward, comparisons between the model and the experimental data show that the model predicts the paperboard’s response well. The mechanical model shows – in combination with experimental strain fields – that multiple delaminations are initiated in the shear regions. Moreover, only the mechanical model reveals the mechanism that is responsible for the failure of the top layer if a crease is too shallow. Finally, the model also demonstrates that not only delamination but also plastic behavior must occur during creasing if breaking of the top layer is to be avoided. [less ▲]

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See detailExperimental and numerical analysis of early age behavior in non-reinforced concrete
Nguyen, Thanh Tung UL; Weiler, Michael UL; Waldmann, Danièle UL

in Construction and Building Materials (2019), 210

An approach combining numerical simulations and experimental techniques is proposed to investigate the early-age properties of non-reinforced concrete. Both thermo-mechanical and fracture behaviors are ... [more ▼]

An approach combining numerical simulations and experimental techniques is proposed to investigate the early-age properties of non-reinforced concrete. Both thermo-mechanical and fracture behaviors are studied, providing a deep insight into the hydration process. This work makes an important step in understanding the effects of hydration on the performance of cement-based materials. More specifically, in the first part, the shrinkage and fracture properties of a non-reinforced concrete have been experimentally considered, along with the characterization of several material parameters. The experimental results exhibit a high risk of early-age cracking for this kind of concrete. Especially, the fracture phenomena are complex, including multi-evolution-stages, initiation, propagation, stop-growing, and re-growing. In the second part, the computational modeling based on the phase field method of failure mechanism is applied to simulate the thermal, mechanical and fracture behavior due to early-age hydration. A detailed discussion on the identification of model/material parameters and the construction of numerical model including the boundary conditions is given. We provide the following comparison between predictions of the numerical simulation with the experimental observations. An excellent predictive capability of the computational model is noted. More importantly, this work demonstrates the performance of the proposed approach, which requires only a few tests to identify the model inputs. Most of the chemo-thermal parameters can be theoretically determined based on the concrete mix and the chemical/mineral compositions of the cement. [less ▲]

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See detailExperimental and numerical assessment of the mechanics of keloid-skin composites undergoing large deformations
Sensale, Marco UL; Chambert, Jerome; Chouly, Franz et al

Scientific Conference (2017, August)

Detailed reference viewed: 96 (9 UL)
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See detailExperimental and Numerical Evaluation of the Residence Time Characteristics on a Forward Acting Grate
Peters, Bernhard UL; Dziugys, A.; Hunsinger, H.

in Condensed Matter 2014 (2014)

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See detailExperimental and numerical evaluation of the transport behaviour of moving bed on a forward acting grate
Peters, Bernhard UL; Dziugys, Algis; Hunsinger, Hans et al

in Granular Matter (2007), 9

Detailed reference viewed: 35 (1 UL)
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See detailExperimental and numerical investigation into iron ore reduction in packed beds
Peters, Bernhard UL; Hoffmann, F.; Senk, D. et al

in Chemical Engineering Science (2015)

Detailed reference viewed: 85 (1 UL)
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See detailExperimental and numerical investigation into the residence time distribution of granular particles on forward and reverse acting grate
Samiei, Kasra UL; Peters, Bernhard UL

in Chemical Engineering Science (2013)

Forward andreverseactinggratesarewidelyemployedinwaste-to-energyplants.Inordertopredict the motionofsolidgranularparticlesandoptimisethedesignofsuchsystems,DiscreteElement Method(DEM)isincreasinglyused ... [more ▼]

Forward andreverseactinggratesarewidelyemployedinwaste-to-energyplants.Inordertopredict the motionofsolidgranularparticlesandoptimisethedesignofsuchsystems,DiscreteElement Method(DEM)isincreasinglyused.Theobjectiveofthispaperistopredictthedynamicsofgranular particlesonforwardandreverseactinggratesbyapplyingDEM.Theresidencetimedistributionofsolid particlesisanalysedbyDEMandcomparedwithexperimentalresultsinapilotplantexcluding combustion.TheresultsindicateaverygoodconsistencybetweenDEMandexperimentalresults, highlightingthepromisingcapabilitiesofDEMinpredictingthedynamicsofgranularparticlesingrate systems.CouplingDEMwithcomputationalfluiddynamicstechniquescanfurtheradvancethemethod to accountforthermalconversionofsolidfuelsinfuturework. [less ▲]

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See detailExperimental and numerical investigation into the softening Behavior of a packed bed of iron ore pellets
Baniasadi, Mehdi UL; Peters, Bernhard UL

in Powder Technology (2018), 339

In this contribution, the softening process of a packed bed of pre-reduced pellets is investigated numerically and experimentally. For this purpose, pellets were reduced to different reduction degrees in ... [more ▼]

In this contribution, the softening process of a packed bed of pre-reduced pellets is investigated numerically and experimentally. For this purpose, pellets were reduced to different reduction degrees in a reduction apparatus. The range of reduction degree (RD) was selected 50 − 80%, which is an acceptable range for iron-bearing materials reaching the cohesive zone. Then, softening experiments under load for a packed bed of pre-reduced pellets in a lab-scale furnace at a temperature range of 800oC to initial melt formation point were carried out. For the modeling part, the newly developed eXtended Discrete Element Method (XDEM) is used. This method is able to predict the deformation of particles over temperature which needs an extension to include heat transfer to DEM. Heat transfer between particle-particle, particle-wall, and particle-gas is considered. To validate the XDEM results with the measurements, an appropriate relationship between Young's modulus of the pellet versus temperature has been estimated. The effect of load on the bed shrinkage is also discussed. FactSage version 7.0 software was used to compute the initial melt point with the phase equilibrium for a 5-component FeO − SiO2 − CaO − MgO − Al2O3 system. [less ▲]

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See detailExperimental and Numerical Investigation on Postcracking Behavior of Steel Fiber Reinforced Concrete
Michels, Julien; Christen, Christen; Waldmann, Danièle UL

in Engineering Fracture Mechanics (2012) (2012)

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See detailAn experimental approach to the dynamics of nuclear polarisation
van den Brandt, B.; Glättli, H.; Grillo, I. et al

in Nuclear Instruments & Methods in Physics Research Section A (2004), 526

In the past 3 years a series of experiments have shed new light on the mechanism of dynamic nuclear polarisation (DNP). Time-resolved polarised small-angle neutron scattering and nuclear magnetic ... [more ▼]

In the past 3 years a series of experiments have shed new light on the mechanism of dynamic nuclear polarisation (DNP). Time-resolved polarised small-angle neutron scattering and nuclear magnetic resonance have been used simultaneously to study the nuclear polarisation build-up around paramagnetic centres during DNP. This approach, which aims at visualising the nuclear polarisation process on a microscopic scale, shall be exemplified and the experimental techniques used described in some detail. [less ▲]

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See detailExperimental characterization of the effects of acute stresslike doses of hydrocortisone in human neurogenic hyperlagesia models
Michaux, Gilles; Magerl, Walter; Anton, Fernand UL et al

in Pain (2012), 153(2), 420-428

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See detailAn experimental comparison of security markets: call-auction vs. double-auction
Neugebauer, Tibor UL

Scientific Conference (2012)

Detailed reference viewed: 61 (0 UL)
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See detailAn Experimental Comparison of Two Exchange Economies: Long-Lived Asset Versus Short-Lived Asset
Neugebauer, Tibor UL; Carbone, Enrica; D. Hey, John

in Management Science (2020)

Detailed reference viewed: 50 (4 UL)
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See detailExperimental design trade-offs for gene regulatory network inference: an in silico study of the yeast Saccharomyces cerevisiae cell cycle
Markdahl, Johan UL; Colombo, Nicolo UL; Thunberg, Johan UL et al

in Proceedings of the 56th IEEE Conference on Decision and Control (2017, December)

Time-series of high throughput gene sequencing data intended for gene regulatory network (GRN) inference are often short due to the high costs of sampling cell systems. Moreover, experimentalists lack a ... [more ▼]

Time-series of high throughput gene sequencing data intended for gene regulatory network (GRN) inference are often short due to the high costs of sampling cell systems. Moreover, experimentalists lack a set of quantitative guidelines that prescribe the minimal number of samples required to infer a reliable GRN model. We study the temporal resolution of data vs.quality of GRN inference in order to ultimately overcome this deficit. The evolution of a Markovian jump process model for the Ras/cAMP/PKA pathway of proteins and metabolites in the G1 phase of the Saccharomyces cerevisiae cell cycle is sampled at a number of different rates. For each time-series we infer a linear regression model of the GRN using the LASSO method. The inferred network topology is evaluated in terms of the area under the precision-recall curve (AUPR). By plotting the AUPR against the number of samples, we show that the trade-off has a, roughly speaking, sigmoid shape. An optimal number of samples corresponds to values on the ridge of the sigmoid. [less ▲]

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See detailExperimental Evaluation of a Tool for Change Impact Prediction in Requirements Models: Design, Results, and Lessons Learned
Göknil, Arda UL; van Domburg, Roderick; Kurtev, Ivan et al

in The Fourth International Model-Driven Requirements Engineering (MoDRE) workshop (2014)

There are commercial tools like IBM Rational RequisitePro and DOORS that support semi-automatic change impact analysis for requirements. These tools capture the requirements relations and allow tracing ... [more ▼]

There are commercial tools like IBM Rational RequisitePro and DOORS that support semi-automatic change impact analysis for requirements. These tools capture the requirements relations and allow tracing the paths they form. In most of these tools, relation types do not say anything about the meaning of the relations except the direction. When a change is introduced to a requirement, the requirements engineer analyzes the impact of the change in related requirements. In case semantic information is missing to determine precisely how requirements are related to each other, the requirements engineer generally has to assume the worst case dependencies based on the available syntactic information only. We developed a tool that uses formal semantics of requirements relations to support change impact analysis and prediction in requirements models. The tool TRIC (Tool for Requirements Inferencing and Consistency checking) works on models that explicitly represent requirements and the relations among them with their formal semantics. In this paper we report on the evaluation of how TRIC improves the quality of change impact predictions. A quasi-experiment is systematically designed and executed to empirically validate the impact of TRIC. We conduct the quasi-experiment with 21 master’s degree students predicting change impact for five change scenarios in a real software requirements specification. The participants are assigned with Microsoft Excel, IBM RequisitePro or TRIC to perform change impact prediction for the change scenarios. It is hypothesized that using TRIC would positively impact the quality of change impact predictions. Two formal hypotheses are developed. As a result of the experiment, we are not able to reject the null hypotheses, and thus we are not able to show experimentally the effectiveness of our tool. In the paper we discuss reasons for the failure to reject the null hypotheses in the experiment. [less ▲]

Detailed reference viewed: 109 (4 UL)