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TABS: Transforming automatically BPMN models into blockchain smart contracts

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Blockchain(Research and Applications) 2023年第1期4卷 90-115页

作者： Peter Bodorik Christian Gang Liu Dawn Jutla Faculty of Computer Science Dalhousie UniversityHalifaxNS B3H 4R2Canada Sobey School of Business Saint Mary's UniversityHalifaxNS B3H 3C3Canada

Research on blockchains addresses multiple issues,with one being the automated creation of smart *** smart contract methods is more difficult than mainstream software development as the underlying blockchain infrastructure poses additional *** report on a new approach to developing smart contracts with the objective of automating the process to increase developer efficiency and reduce the risk of errors introduced by software *** support industry adoption,we use Business Process Model and Notation(BPMN)modeling to describe an application while targeting applications in the trade *** describe a system that transforms a BPMN model into a multi-modal model that combines Discrete Event(DE)modeling for concurrency with Hierarchical State Machines(HSMs)to represent application ***,further transformations are used to transform the DE-HSM model into methods in smart *** system lets the modeler decide which of the independent patterns should be transformed into methods of a separate smart contract that is deployed on a sidechain for the purpose of(i)reducing processing costs and/or(ii)providing privacy so that other participants in the smart contract do not have visibility into the processing of the *** also briefly describe a proof-of-concept tool we built to demonstrate the feasibility of our approach.

关键词： Blockchain Business processes modeling notation(BPMN) Discrete event(DE)modeling Finite state machine(FSM) Hierarchical state machines(HSM) Smart contract Off-chain computation Privacy Smart contract interoperability

Estimates for the local permeability of the Cobourg limestone

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第6期10卷 1009-1019页

作者： A.P.S.Selvadurai A.Glowacki Department of Civil Engineering and Applied Mechanics McGill UniversityMontréalQCH3A 0C3Canada

Argillaceous limestone formations are being proposed as sites suitable for constructing a deep geologic repository for storing low-to intermediate-level nuclear waste in southern Ontario, Canada. The Cobourg limestone is characterized by a visual appearance of heterogeneity resulting from light gray calcite nodular regions interspersed with dark gray calcite-dolomite-quartz partings containing a clay component. This paper presents the results of experiments conducted to determine the permeability of both the light gray and the dark gray species of the Cobourg limestone. The permeabilities were successfully estimated from both steady state and hydraulic pulse tests conducted using specially designed miniature water entry ports, which were epoxied to the surface of the rock sample containing cavities drilled into the rock species of interest. The results show that the dark gray species of the Cobourg limestone has a permeability that is roughly one order of magnitude greater than the light gray calcite species.

关键词： Cobourg limestone Permeability Steady state tests Hydraulic pulse tests

Effect of concentration quenching on the spectroscopic properties of Er^(3+)/Yb^(3+) co-doped AlF_3-based glasses

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Chinese Optics Letters 2004年第10期2卷 600-603页

作者：张军杰戴世勋徐时清汪国年张丽艳胡丽丽 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 series of highly Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption emission and upconversion spectra have been performed to examine the effect of Er~(3+)/Yb~(3+) concentration quenching on spectroscopic properties. In the glasses with Er~(3+) concentrations below 10 mol% concentration quenching is very low and the Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have stronger fluorescence of 1.54μm due to the ~4I_(13/2)→~4I_(15/2) transition than that of Er~(3+) singly-doped glasses. As Er~(3+) concentrations above 10 mol% in the Er~(3+)/Yb~(3+) co-doped samples concentration quenching of 1.54μm does obviously occur as a result of the back energy transfer from Er~(3+) to Yb~(3+). To obtain the highest emission efficiency at 1.54μm the optimum doping-concentration ratio of Er~(3+)/Yb~(3+) was found to be approximately 1:1 in mol fraction when the Er~(3+) concentration is less than 10 mol%.

A series of highly Er^(3+)/Yb^(3+) co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and upconversion spectra have been performed to examine the effect of Er^(3+)/Yb^(3+) concentration quenching on spectroscopic properties. In the glasses with Er^(3+) concentrations below 10 mol%, concentration quenching is very low and the Er^(3+)/Yb^(3+) co-doped fluoroaluminate glasses have stronger fluorescence of 1.54μm due to the ~4I_(13/2)→~4I_(15/2) transition than that of Er^(3+) singly-doped glasses. As Er^(3+) concentrations above 10 mol% in the Er^(3+)/Yb^(3+) co-doped samples, concentration quenching of 1.54μm does obviously occur as a result of the back energy transfer from Er^(3+) to Yb^(3+). To obtain the highest emission efficiency at 1.54μm, the optimum doping-concentration ratio of Er^(3+)/Yb^(3+) was found to be approximately 1:1 in mol fraction when the Er^(3+) concentration is less than 10 mol%.

关键词： Yb co-doped AlF3-based glasses Effect of concentration quenching on the spectroscopic properties of Er

Ehrhart Polynomials of 3-Dimensional Simple Integral Convex Polytopes

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1345-1352页

作者： Yusuke SUYAMA Department of Mathematics Graduate School of ScienceOsaka City University3=3-138 SugimotoSumiyoshi=kuOsaka 558-8585Japan.

The author gives an explicit formula on the Ehrhart polynomial of a 3-dimensional simple integral convex polytope by using toric geometry.

关键词： Integral convex polytopes Ehrhart polynomials Toric geometry

Mining Object Similarity for Predicting Next Locations

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Journal of Computer Science & Technology 2016年第4期31卷 649-660页

作者： Meng Chen Xiaohui Yu Yang Liu School of Computer Science and Technology Shandong University Jinan 250101 China School of Information Technology York University Toronto M3J1P3 Canada

Next location prediction is of great importance for many location-based applications. With the virtue of solid theoretical foundations, Markov-based approaches have gained success along this direction. In this paper, we seek to enhance the prediction performance by understanding the similarity between objects. In particular, we propose a novel method, called weighted Markov model （weighted-MM）, which exploits both the sequence of just-passed locations and the object similarity in mining the mobility patterns. To this end, we first train a Markov model for each object with its own trajectory records, and then quantify the similarities between different objects from two aspects： spatial locality similarity and trajectory similarity. Finally, we incorporate the object similarity into the Markov model by considering the similarity as the weight of the probability of reaching each possible next location, and return the top-rankings as results. We have conducted extensive experiments on a real dataset, and the results demonstrate significant improvements in prediction accuracy over existing solutions.

关键词： weighted Markov model next location prediction object similarity

Effects of coal seam dip angle on the outburst in coal roadway excavation

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International Journal of Mining Science and Technology 2019年第5期29卷 757-764页

作者： Cheng Hou Yinghua Zhang Yi Yan University of Science and Technology Beijing Beijing 100083China Department of Mechanical Engineering McGill UniversityMontrealQC H3A 0C3Canada

The prevention and forecast of coal and gas outburst has always been one of the key issues in coal mining *** simulating the process of tunneling in coal seam with different dip angle through FLAC3D software,the dangerous zone in which outburst may occur and the probability of outburst near the working face were predicted through the distribution of stress,displacement and plastic *** we discussed the size of unstable area in the surrounding rock through the distribution of stress and the variation curve of the displacement on the roadway *** results show that,with an increase of the coal seam dip angle,the risk of outburst in the working face rises *** the dangerous areas in which may outburst occur moves to the upper part of coal *** size of unstable area in the surrounding rock increases with the increase of coal seam dip angle.

关键词： Dip angle Stress concentration Plastic zone Displacement Coal and gas outburst

Thermodynamic database development—modeling and phase diagram calculations in oxide systems

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Rare Metals 2006年第5期25卷 473-480页

作者： Arthur D.Pelton Center for Research in Computational Thermochemistry Ecole PolytechniqueP.O.Box 6079Station "Downtown"MontrealQuebec H3C 3A7Canada

The databases of the FactSage thermodynamic computer system have been under development for 30 years. These databases contain critically evaluated and opthnized data for thousands of compounds and hundreds of multicomponent solutions of solid and liquid metals, oxides, salts, sulfides, etc. The databases are automatically accessed by user-friendly software that calculates complex multiphase equilibria in large multicomponent systems for a wide variety of possible input/output constraints. The databases for solutions have been developed by critical evaluation/optimization of all available phase equilibrium and thermodynamic data. The databases contain parameters of models specifically developed for different types of solutions involving sublattices, ordering, etc. Through the optimization process, model parameters are found which reproduce all thermodynamic and phase equilibrium data within experimental error limits and permit extrapolation into regions of tempea＇ature and composition where data are unavailable. The present article focuses on the databases for solid and liquid oxide phases involving 25 elements. A short review of the available databases is presented along with the models used for the molten slag and the solid solutions such as spinel, pyroxene, olivine, monoxide, corundum, etc. The critical evaluation/optimization procedure is outlined using examples from the Al203-SiO2-CaO-FeO-Fe2O3 system. Sample calculations are presented in which the oxide databases are used in conjunction with the FactSage databases for metallic and other phases. In particular, the use of the FactSage module for the calculation of multicomponent phase diagrams is illustrated.

关键词： thermodynamics oxides databases phase diagrams

Continuous-wave optical enhancement cavity with 30-kW average power

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Chinese Physics B 2023年第3期32卷 258-261页

作者：柳兴陆心怡王焕颜立新李任恺黄文会唐传祥 Ronic Chiche Fabian Zomer Department of Engineering Physics Tsinghua UniversityBeijing 100084China UniversitéParis-Saclay CNRS/IN3 P3IJCLab91405 OrsayFrance

Optical enhancement cavity(OEC)is a powerful tool for fundamental research and *** this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-state microbunching(SSMB)mechanism,is *** efficiently suppressing all external noise and optimizing the alignment,mode-matching,and polarization matching,stable and long-term locking is achieved with the help of two feedback *** modal instability phenomenon caused by the surface thermoelastic deformation is observed.A pair of D-shape mirrors are utilized to remove the high-order ***,an intra-cavity average power of 30 kW is reached.

关键词： optical enhancement cavity continuous-wave laser modal instability high power cavity

A review of rapid transport of pesticides from sloping farmland to surface waters: Processes and mitigation strategies

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Journal of Environmental Sciences 2012年第3期24卷 351-361页

作者： Xiangyu Tang Bo Zhu Hidetaka Katou Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China National Institute for Agro-Environmental Sciences Kannondai 3-1-3Tsukuba 305-8604Japan

Pesticides applied to sloping farmland may lead to surface water contamination through rapid transport processes as influenced by the complex topography and high spatial variability of soil properties and land use in hilly or mountainous regions. However, the fate of pesticides applied to sloping farmland has not been sufficiently elucidated. This article reviews the current understanding of pesticide transport from sloping farmland to surface water. It examines overland flow and subsurface lateral flow in areas where surface soil is underlain by impervious subsoil or rocks and tile drains. It stresses the importance of quantifying and modeling the contributions of various pathways to rapid pesticide loss at catchment and regional scales. Such models could be used in scenario studies for evaluating the effectiveness of possible mitigation strategies such as constructing vegetated strips, depressions, wetlands and drainage ditches, and implementing good agricultural practices. Field monitoring studies should also be conducted to calibrate and validate the transport models as well as biophysical-economic models, to optimize mitigation measures in areas dominated by sloping farmland.

关键词： pesticide rapid transport sloping farmland overland flow subsurface flow