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Economic and Political Studies 2023年第3期11卷 334-349页

作者： Stephan Muehlbacher Andre Hartmann Erich Kirchler James Alm Department of Psychology and Psychodynamics Karl Landsteiner University of Health SciencesKremsAustria Department of Occupational Economic and Social PsychologyUniversity of ViennaViennaAustria Institute for Advanced Studies ViennaAustria Department of Economics Tulane UniversityNew OrleansLAUSA

laboratory experiments are frequently criticised,in part because of the sensitivity of the results to specific features of the *** paper addresses an important question regarding the key aspect of the experimental environment:How should the dependent variable–participants’choices–be operationalised?For the specific context of laboratory research on income tax compliance,we compare the effects of the two most common operationalisation types:the declaration of gross income versus the declaration of tax *** is found that compliance is higher when participants indicate their tax payment than when they declare their *** is also discovered that the effects of the three policy parameters of the economic model(the tax rate,audit probability and fine rate)are stronger when participants declare their taxes than when they declare their *** results are relevant for interpreting prior and future experimental evidence on tax compliance and can explain some contradictory previous *** broadly,this study suggests that the results of laboratory experiments may depend on specific features of the experimental design,which proposes a strong need for more systematic methodological research.

关键词： laboratory experiments experimental design tax compliance tax rate audit probability fine rate

3D Mobile Augmented Reality Interface for laboratory experiments

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International Journal of Communications, Network and System Sciences 2016年第4期9卷 67-76页

作者： Clement Onime Olatunde Abiona Information and Communication Technology Section Abdus Salam International Centre for Theoretical Physics Trieste Italy Department of Computer Information Systems Indiana University Northwest Gary IN USA

In fields such as science and engineering, virtual environment is commonly used to provide replacements for practical hands-on laboratories. Sometimes, these environments take the form of a remote interface to the physical laboratory apparatus and at other times, in the form of a complete software implementation that simulates the laboratory apparatus. In this paper, we report on the use of a semi-immersive 3D mobile Augmented Reality (mAR) interface and limited simulations as a replacement for practical hands-on laboratories in science and engineering. The 3D-mAR based interfaces implementations for three different experiments (from micro-electronics, power and communications engineering) are presented;the discovered limitations are discussed along with the results of an evaluation by science and engineering students from two different institutions and plans for future work.

关键词： Mobile Augmented Reality laboratory experiments 3D

Hydrodynamic modelling of flow impact on structures under extreme flow conditions

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Journal of Hydrodynamics 2016年第2期28卷 267-274页

作者： Qiuhua LIANG 陈恺翠 Jingming HOU 熊焱王岗羌娟 Key laboratory of Coastal Disaster and Protection Ministry of Education Hohai University School of Civil Engineering and Geosciences Newcastle University Newcastle upon Tyne England

Apart from the direct threat to human lives, the flood waves as a result of the rapid catchment response to intense rainfall, breaches of flood defences, tsunamis or storm surges may induce huge impact forces on structures, causing structural damage or even failures. Most existing design codes do not properly account for these impact forces due to the limited understanding of the underlying physical processes and the lack of reliable empirical formulae or numerical approaches to quantifying them. This paper presents laboratory experiments to better understand the interaction between the extreme flow hydrodynamics and the hydraulic structures and uses the measured data to validate a numerical model. The model solves the two-dimensional shallow water equations using a finite volume Godunov-type scheme for the reliable simulation of complex flow hydrodynamics. New model components are developed for estimating the hydrostatic and hydrodynamic pressure to quantify the flow impact on structures. The model is applied to reproduce two selected experiment tests with different settings and satisfactory numerical results are obtained, which confirms its predictive capability. The model will therefore provide a potential tool for wider and more flexible field-scale applications.

关键词： wave-structure interaction extreme flow conditions flood hazards shallow flow model laboratory experiments

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experiments and calculations of wave breaking and evolution of wave groups with high steepness

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Journal of Hydrodynamics 2022年第5期34卷 975-980页

作者： Wen-yang Duan Kun Zheng Bin-bin Zhao College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

The evolution of the nonlinear wave groups in deep water is investigated through laboratory measurements and numerical *** experiments are conducted in deep-water wave tank,focusing on the characteristics of breaking waves arising from the evolved wave *** quantitative results are obtained for the significant breaking wave train,including the surface elevation time series,the local geometry,and the energy dissipation.A nonlinear model for the evolution of the wave groups in deep water is developed by adding eddy viscosity dissipation terms in the High Level Irrotational Green-Naghdi(HLIGN)*** results of the simulation are compared with the laboratory measurements,and good agreement is observed for the evolved wave train.

关键词： Wave group evolution wave breaking High-Level Irrotational Green-Naghdi(HLIGN)equations laboratory experiments

Experimental arena settings might lead to misinterpretation of movement properties

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Insect Science 2024年第1期31卷 271-284页

作者： Inon Scharf Kimberley Hanna Daphna Gottlieb The George S.Wise Faculty of Life Sciences School of ZoologyTel Aviv UniversityTel AvivIsrael Department of Food Science Institute of Post-Harvest and Food ScienceVolcani CenterARORishon LeZionIsrael

Movement is an important animal behavior contributing to reproduction and *** movement is often examined in arenas or enclosures under laboratory *** used the red flour beetle(Tribolium castaneum)to examine here the effect of the arena size,shape,number of barriers,access to the arena's center,and illumination on six movement *** demonstrate great differences among *** example,the beetles moved over longer distances in clear arenas than in obstructed *** along the arena's perimeter was greater in smaller arenas than in larger *** was more directional in round arenas than in rectangular *** general,the beetles stopped moving closer to the perimeter and closer to corners(in the square and rectangular arenas)than expected by *** some cases,the arena properties interacted with the beetle sex to affect several movement *** these suggest that arena properties might also interact with experimental manipulations to affect the outcome of studies and lead to results specific to the arena *** other words,instead of examining animal movement,we in fact examine the animal interaction with the arena *** is therefore advised in interpreting the results of studies on movement in arenas under laboratory conditions and we recommend paying attention also to barriers or obstacles in field *** instance,movement along the arena's perimeter is often interpreted as centrophobism or thigmotaxis but the results here show that such movement is arena dependent.

关键词： activity centrophobism correlated random walk laboratory experiments movement ecology wall-following behavior

Pyrite-hydrocarbon Interaction under Hydrothermal Conditions: an Alternative Origin of H_2S and Organic Sulfur Compounds in Sedimentary Environments

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 2133-2148页

作者： DING Kangle MEI Ping LUO Yue Key laboratory of Exploration Technologies for Oil and Gas Resources of Ministry of Education Yangtze University State Key laboratory of Petroleum Resources and Prospecting China University of Petroleum School of Chemistry and Environmental Engineering Yangtze University

Sulfate rocks and organic sulfur from sedimentary organic matter are conventionally assumed as the original sulfur sources for hydrogen sulfide （H2S） in oil and gas reservoirs. However, a few recent experiments preliminarily indicate that the association of pyrite and hydrocarbons may also have implications for H2S generation, in which water effects and natural controls on the evolution of pyrite sulfur into OSCs and H2S have not been evaluated. In this study, laboratory experiments were conducted from 200 to 450°C to investigate chemical interactions between pyrite and hydrocarbons under hydrothermal conditions. Based on the experimental results, preliminary mechanism and geochemical implications were tentatively discussed. Results of the experiments showed that decomposition of pyrite produced H2S and thiophenes at as low as 330°C in the presence of water and n-pentane. High concentrations of H2S were generated above 450°C under closed pyrolysis conditions no matter whether there is water in the designed experiments. However, much more organic sulfur compounds （OSCs） were formed in the hydrous pyrolysis than in anhydrous pyrolysis. Generally, most of sulfur liberated from pyrite at elevated temperatures was converted to H2S. Water was beneficial to breakdown of pyrite and to decomposition of alkanes into olefins but not essential to formation of large amounts of H2S, given the main hydrogen source derived from hydrocarbons. In addition, cracking of pyrite in the presence of 1-octene under hydrous conditions was found to proceed at 200°C, producing thiols and alkyl sulfides. Unsaturated hydrocarbons would be more reactive intermediates involved in the breakdown of pyrite than alkanes. The geochemistry of OSCs is actually controlled by various geochemical factors such as thermal maturity and the carbon chain length of the alkanes. This study indicates that the scale of H2S gas generated in deep buried carbonate reservoirs via interactions between pyrite and natural

关键词： laboratory experiments pyrite hydrocarbon H2S OSCs geochemical implications

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laboratory Observations on Internal Solitary Wave Evolution over A Submarine Ridge

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China Ocean Engineering 2006年第1期20卷 61-72页

作者： Chen-Yuan CHEN John Rong-Chung HSU Ching-Feng KUO Hsin-Hsun CHEN Min-Hung CHENG Department of Marine Environment and Engineering National Sun Yat-sen University Kaohsiung 80424 Taiwan China Honorary Research Fellow School of Civil and Resource Engineering University of Western Australia WA 6009 Australia Institute of Physical Oceanography National Sun Yat-sen University Kaohsiung 80424 Taiwan China

laboratory experiments were conducted in a wave flume on internal solitary wave （ISW） of depression and elevation types propagating over a submarine ridge in semicircular/triangular shape. Tests were arranged in series for combinations of submarine ridges of different heights and ISW of different amplitudes. The resuhant wave motions were found differing from thee of surface gravity waves. In deeper water, where an ISW of depression-type prevailed, the process of wave breaking displayed downward motion with continuous eddy on the front face of the ridge followed by upward motion towards the apex of the obstacle. Experimental results also suggested that blockage parameter ξ could be applied to classify various degrees of ISW-ridge interaction, i.e., ξ 〈 0.5 for weak interaction, 0.5 〈 ξ 〈 0.7 for moderate interaction, and 0.7 〈 ξ for wave breaking.

关键词： internal solitary wave laboratory experiments wave dispersion energy loss profile change

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laboratory measurements of the fall velocity of fine sediment in an estuarine environment

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International Journal of Sediment Research 2020年第2期35卷 217-226页

作者： Jiaqi Yang Limo Tang Yuntong She Jiao Sun State Key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University Department of Civil and Environmental Engineering University of Alberta Zhejiang Qianjiang Science and Technology Development Company

The study of the fall velocity variation of fine sediment in estuarine areas plays an important role in determining how various factors affect the flocculation *** experimental studies have focused solely on the relation between the median fall velocity and influencing factors,while in the current study,the variation of the fall velocity in quiescent water also was *** experimental results showed that the vertical distribution of sediment concentration was more uneven,and larger variations occurred earlier during the settling process under higher salinity and/or sediment concentration *** fall velocity initially increased then decreased over time,peaking at～20 min after settling began,and stabilizing at a value similar to that in freshwater,regardless of the initial sediment concentration and salinity *** the water depth,the fall velocity increased monotonically with a gradually decreasing *** median fall velocity increased then decreased with increased *** salinity at which the peak fall velocity occurred depended on the initial sediment *** relation between the median fall velocity and initial sediment concentration displayed an obvious two-stage pattern(i.e.,accelerated flocculation and decelerated,hindered settling) at higher salinities;whereas the maximum median fall velocity was observed at two consecutive sediment concentration values under lower salinity ***,an empirical equation estimating the median fall velocity of cohesive fine sediment was formulated,incorporating the effects of both salinity and sediment concentration.

关键词： laboratory experiments Fine sediment Estuarine environment Fall velocity Salinity Sediment concentration

Erosion pattern of artificial gravel deposits

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International Journal of Sediment Research 2018年第1期33卷 57-67页

作者： Fabian Friedl Volker Weitbrecht Robert M.Boes laboratory of Hydraulics Hydrology and Glaciology (VAW)ETH Zurich

Sediment replenishment with artificial gravel deposits is an option to compensate for sediment deficits in rivers and to improve their ecological conditions. Predicting and quantifying the erosion rate of an artificial gravel deposit is important to successfully perform river restoration projects. laboratory experiments have been done to investigate the influence of various parameters on the erosion pattern of artificial gravel deposits. In the present paper the effects of deposit geometry, bulk density, grain size distribution, and hydraulic load on the erosion process are described. The temporal evolution of the deposit geometry and the corresponding mean erosion rates were studied. The mean erosion rate increases with deposit height, deposit width, and decreasing grain size. Furthermore, no significant impact of the bulk density was observed. Equations to predict the mean erosion rate are proposed. This investigation helps to determine the design frequency of gravel dumping and deposit volumes for restoration projects.

关键词： Artificial gravel deposits Bed load transport laboratory experiments Sediment replenishment

On the way to airborne gravelometry based on 3D spatial data derived from images

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International Journal of Sediment Research 2018年第1期33卷 84-92页

作者： M.Detert L.Kadinski V.Weitbrecht laboratory of Hydraulics Hydrology and Glaciology VAWETH Zurich

This paper presents basic tests to develop an airborne photogrammetric methodology that derives grain size characteristics of gravel bed rivers. The data acquisition was done using a light weight action cam and a hand-held digital single lens reflex camera. Image processing comprised the structure from motion technique and multiview-stereo algorithms to obtain digital elevation models of non-cohesive gravel beds. laboratory results indicate that the method accuracy is about four to six times lower than laserscan data when based on action cam data. The accuracy of digital elevation models computed via photos taken by the reflex camera is almost of the same range as the laser data. Field experiments were done to test the performance of image based gravelometry against manual surface sampling. For this application the action cam was mounted to a low-cost quadrocopter, while the reflex camera was operated by *** indicate that this combination has a high potential to generate data from which characteristic grain size parameters can be estimated.

关键词： Airborne photogrammetry Grain size distribution Gravel bed Field work Gravelometry Image analysis laboratory experiments Structure from motion Surface sampling