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Development of a Bayesian inference model for assessing ventilation condition based on CO_(2)meters in primary schools

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Building Simulation 2023年第1期16卷 133-149页

作者： Danlin Hou Liangzhu(Leon)Wang Ali Katal Shujie Yan Liang(Grace)Zhou Vicky Wang Mark Vuotari Ethan Li Zihan Xie Centre for Zero Energy Building Studies Department of BuildingCivil and Environmental EngineeringConcordia University1455 de Maisonneuve Blvd.WestMontrealQuebecH3G 1M8Canada Construction Research Centre Engineering DivisionNational Research Council of CanadaM-241200 Montreal RoadOttawaOntario K1A 0R6Canada

Outdoor fresh air ventilation plays a significant role in reducing airborne transmission of diseases in indoor *** classrooms are considerably challenged during the COVID-19 pandemic because of the increasing need for in-person education,untimely and incompleted vaccinations,high occupancy density,and uncertain ventilation *** schools started to use CO_(2)meters to indicate air quality,but how to interpret the data remains *** uncertainties are also involved,including manual readings,student numbers and schedules,uncertain CO_(2)generation rates,and variable indoor and ambient *** study proposed a Bayesian inference approach with sensitivity analysis to understand CO_(2)readings in four primary schools by identifying uncertainties and calibrating key *** outdoor ventilation rate,CO_(2)generation rate,and occupancy level were identified as the top sensitive parameters for indoor CO_(2)*** occupancy schedule becomes critical when the CO_(2)data are limited,whereas a 15-min measurement interval could capture dynamic CO_(2)profiles well even without the occupancy *** CO_(2)recording should be avoided because it failed to capture peak values and overestimated the ventilation *** the four primary school rooms,the calibrated ventilation rate with a 95%confidence level for fall condition is 1.96±0.31 ACH for Room#1(165 m^(3)and 20 occupancies)with mechanical ventilation,and for the rest of the naturally ventilated rooms,it is 0.40±0.08 ACH for Room#2(236 m^(3)and 21 occupancies),0.30±0.04 or 0.79±0.06 ACH depending on occupancy schedules for Room#3(236 m^(3)and 19 occupancies),0.40±0.32,0.48±0.37,0.72±0.39 ACH for Room#4(231 m^(3)and 8–9 occupancies)for three consecutive days.

关键词： COVID-19 Bayesian calibration Markov Chain Monte Carlo ventilation rate school CO_(2)

Path Following Control for UAV Using Deep Reinforcement Learning Approach

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Guidance, Navigation and Control 2021年第1期1卷 91-108页

作者： Yintao Zhang Youmin Zhang Ziquan Yu Department of Mechanical Industrial and Aerospace EngineeringConcordia University1455 De Maisonneuve Boulevard WestMontrealQuebec H3G 1M8Canada College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China

Unmanned aerial vehicles(UAVs)have been extensively used in civil and industrial applications due to the rapid development of the guidance,navigation and control(GNC)***,using deep reinforcement learning methods for motion control acquires a major progress recently,since deep Q-learning algorithm has been successfully applied to the continuous action domain *** paper proposes an improved deep deterministic policy gradient(DDPG)algorithm for path following control problem of UAV.A speci-c reward function is designed for minimizing the cross-track error of the path following *** the training phase,a double experience replay bu®er(DERB)is used to increase the learning e±ciency and accelerate the convergence ***,the model of UAV path following problem has been *** that,the framework of DDPG algorithm is *** the state space,action space and reward function of the UAV path following algorithm are *** is proposed to accelerate the training ***,simulation results are carried out to show the e®ectiveness of the proposed DERB–DDPG method.

关键词： Path following deep deterministic policy gradient double experience replay bu®er

Effect of Oocyte Recovery Techniques on in Vitro Production of Swine Embryos

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Open Journal of Animal Sciences 2015年第4期5卷 467-473页

作者： Mariana Groke Marques Flavia Regina Oliveira de Barros Marcelo Demarchi Goissis Mariana Ianello Giassetti Mayra Elena Ortiz D’Avila Assumpcao Jose Antonio Visintin EMBRAPA Swine and Poultry Research Center ConcordiaBrazil Department of Animal Reproduction School of Veterinary Medicine and Animal SciencesUniversity of Sao PauloSao PauloBrazil

In Vitro production of swine embryos is a valuable tool to generate clones and genetically modified pigs during a short period of time. However, the efficiency of the existing methods is extremely low and the oocyte quality and quantity represent important obstacles on the success of in Vitro production of embryos. Therefore, the aim of this study was to compare the in Vitro maturation, fertilization and subsequent embryo development rates of oocytes recovered by ovary slicing or follicular aspiration. The oocyte recovery rate (grade 1 COC/ovary) was higher (p = 0.0083) in the slicing group when compared to the aspiration group. No differences were observed between groups regarding in Vitro maturation and early cleavage rates. A higher percentage of oocytes recovered by follicular aspiration reached the blastocyst stage after IVF when compared to the ovary slicing method (p = 0.0395). However, no difference on blastocyst cell number was observed. Although the recovery of oocytes using the slicing technique yielded more grade 1 oocytes per ovary than the aspiration method, the number of oocytes that reached the blastocyst stage after IVF by the slicing method was lower when compared with oocytes obtained by aspiration, as observed by lower blastocyst rates. In conclusion, the follicular aspiration is the method of choice for porcine in Vitro embryo production.

关键词： Oocyte Recovery Oocyte Maturation HSP70 Embryo Development Swine

Aerial refueling scheduling of multi-receiver and multi-tanker under spatial-temporal constraints for forest firefighting

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Chinese Journal of Aeronautics 2024年第5期37卷 71-91,I0001页

作者： Jing HUANG Jiaqi XING Jinrui REN Quan QUAN Youmin ZHANG Department of Information and Control Engineering Xi’an University of TechnologyXi’an 710048China Jiujiang Measuring Test Technology Research Institute Jiujiang 332000China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Automation Xi’an University of Posts&TelecommunicationsShaanxiXi’an 710121China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontreal H3G 1M8Canada

Forest fires pose a significant threat to human life and property,so the utilization of unmanned aircraft systems provides new ways for forest *** the constrained load capacities of these aircraft,aerial refueling becomes crucial to extend their operational time and *** order to address the complexities of firefighting missions involving multi-receiver and multi-tanker deployed from various airports,first,a fuel consumption calculation model for aerial refueling scheduling is established based on the receiver ***,two distinct methods,including an integrated one and a decomposed one,are designed to address the challenges of establishing refueling airspace and allocating tasks for *** methods aim to optimize total fuel consumption of the receivers and tankers within the aerial refueling scheduling *** optimization problem is established as nonlinear optimization models along with *** integrated method seamlessly combines refueling rendezvous point scheduling and tanker task allocation into unified *** has a complete solution space and excels in optimizing total fuel *** decomposed method,through the separation of rendezvous point scheduling and task allocation,achieves a reduced computational ***,this comes at the cost of sacrificing optimality by excluding specific feasible ***,numerical simulations are carried out to verify the feasibility and effectiveness of the proposed *** simulations yield insights crucial for the practical engineering application of both the integrated and decomposed methods in real-world *** comprehensive approach aims to enhance the efficiency of forest firefighting operations,mitigating the risks posed by forest fires to human life and property.

关键词： Aerial refueling Scheduling Planning Spatial-temporal constraint Firefighting

Preparation of Fe-As alloys by mechanical alloying and vacuum hot-pressed sintering:microstructure evolution,mechanical properties,and mechanisms

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Rare Metals 2024年第8期43卷 3876-3892页

作者： Fei Chai Fei-Ping Zhao Zhan Hu Shi-Yi Wen Ben-Hammouda Samia Ze-Lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo Min Li-Yuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Institute of Environmental EngineeringCentral South UniversityChangsha 410083HunanChin State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Building Civiland Environmental EngineeringConcordia UniversityMontreal H3G 1M8Canada

Arsenic materials have attracted great attention due to their unique ***,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting point of ***,a new Fe-As alloy was obtained by mechanical alloying(MA) followed by vacuum hot-pressed sintering(VHPS).Moreover,a systematic study was carried out on the microstructural evolution,phase composition,leaching toxicity of As,and physical and mechanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed metallic powders(PAMPs) have a fine grain size and specific supersaturated solid solution after MA,which could effectively improve the mechanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm^(-3)),low toxicity,and excellent mechanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate amount of As,which is more valuable than commercial Fe-As *** Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm^(-3)) provides an ultra-high compressive strength(1989.19 MPa),while the Fe-65% As alloy owns the maximum Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still maintain good mechanical performance,and the strengthening mechanisms of Fe-As alloys before and after leaching were *** in the grain size,micro structure,and phase distribution induced significant differences in the compressive strength and hardness.

关键词： Mechanical alloying Vacuum hot-pressed sintering High-pressure Arsenic-iron alloys Mechanical properties

Adaptive Consensus Quantized Control for a Class of High-Order Nonlinear Multi-Agent Systems With Input Hysteresis and Full State Constraints

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IEEE/CAA Journal of Automatica Sinica 2022年第9期9卷 1574-1589页

作者： Guoqiang Zhu Haoqi Li Xiuyu Zhang Chenliang Wang Chun-Yi Su Jiangping Hu the School of Automation Engineering Northeast Electric Power UniversityJilin 132012 the Jilin Province International Research Center of Precision Drive and Intelligent Control Jilin 132012China the School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China the Department of Mechanical and Industrial Engineering Concordia UniversityQCMontrealH3B 1R6Canada the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China(

For a class of high-order nonlinear multi-agent systems with input hysteresis,an adaptive consensus output-feedback quantized control scheme with full state constraints is *** major properties of the proposed control scheme are:1)According to the different hysteresis input characteristics of each agent in the multi-agent system,a hysteresis quantization inverse compensator is designed to eliminate the influence of hysteresis characteristics on the system while ensuring that the quantized signal maintains the desired value.2)A barrier Lyapunov function is introduced for the first time in the hysteretic multi-agent *** constructing state constraint control strategy for the hysteretic multi-agent system,it ensures that all the states of the system are always maintained within a predetermined range.3)The designed adaptive consensus output-feedback quantization control scheme allows the hysteretic system to have unknown parameters and unknown disturbance,and ensures that the input signal transmitted between agents is the quantization value,and the introduced quantizer is implemented under the condition that only its sector bound property is *** stability analysis has proved that all signals of the closed-loop are semi-globally uniformly *** Star Sim hardware-in-the-loop simulation certificates the effectiveness of the proposed adaptive quantized control scheme.

关键词： Adaptive quantized control barrier Lyapunov function input hysteresis multi-agent systems

Mismatch between calf paternity and observed copulations between male and female reindeer:Multiple mating in a polygynous ungulate?

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Current Zoology 2023年第4期69卷 377-384页

作者： Keenin R.Coombs Robert B.Weladji Ostein Holand Knut H.Rodc Department of Biology Concordia University7141 Sherbrooke St.WestMontrealQCH4B1R6Canada Department of Animal and Aquacultural Sciences Norwegian University of Life SciencesOluf Thesens vei 61433ÅsNorway Faculty of Veterinary Medicine Norwegian University of Life SciencesVeterinærbygningenElizabeth Stephansens vei 15N-1430ÅsNorway

In polygynous systems,such as that exhibited by reindeer Rangifer tarandus,mate choice can be difficult to disentangle from male intrasexual competition because male behavior may constrain female *** mating may provide an avenue for female mate choice,though it is difficult to identify using behavioral estimators *** techniques address this issue by affording ecologists an opportunity to reassess mating systems from a genetic *** assessed the frequency and possible explanations for multiple mating in reindeer using a genetic approach to determine the success of observed copulations in a semi-domesticated herd in Kaamanen,*** and genetic data were synthesized with population characteristics over a 7-year period to test the hypothesis that,if present,polyandry in reindeer is driven by sexual harassment from sub-dominant *** observed multiple mating in 42%of females,with as many as 60%exhibiting multiple mating in certain *** found no evidence that multiple mating resulted from sexual harassment by sub-dominant males,suggesting that it is likely a deliberate strategy among *** rate of copulations into paternities varied with male size,with smaller males more likely to experience mismatch than larger *** preference for larger males persisted despite the occurrence of multiple mating,possibly suggesting a mechanism for cryptic post-copulatory *** suggest further research to delineate the possible influence of cryptic post-copulatory selection and multiple mating to defend against infertility in exhausted males.

关键词： female choice mate choice mating systems polyandry reproductive success sexual selection

基于STEP和XML的网络化制造系统的信息共享

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计算机集成制造系统-CIMS 2002年第7期8卷 561-564页

作者：仇晓黎易红吴锡英陈明远东南大学机械系江苏南京210096 concordia大学工业工程系

在网络化设计和制造中 ,如何通过互联网来实现异质系统之间的信息协调是需要解决的一个重要问题。本文提出了一种建立在STEP和可扩展标记语言基础上 ,可以使一个CAD系统和另一个CAx系统通过互联网而实现信息共享的方法。介绍了相关的STE... 详细信息

在网络化设计和制造中 ,如何通过互联网来实现异质系统之间的信息协调是需要解决的一个重要问题。本文提出了一种建立在STEP和可扩展标记语言基础上 ,可以使一个CAD系统和另一个CAx系统通过互联网而实现信息共享的方法。介绍了相关的STEP标准和XML概念 ,以及相对应的EXPRESS和DTD标准。同时介绍了如何将STEP和XML作为中性格式模型集成在一起的思路。最后。

关键词： STEP XML 信息共享网络化制造系统敏捷制造 CAD CIMS

Compensatory foraging in Trinidadian guppies： Effects of acute and chronic predation threats

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Current Zoology 2014年第3期60卷 323-332页

作者： Chris K. ELVIDGE Indar RAMNARINE Grant E. BROWN Department of Biology Concordia University 7141 Sherbrooke St West Montreal QC H4B 1R6 Canada Department of Life Sciences University of the West Indies St Augustine Trinidad and Tobago

In response to acute predation threats, prey may sacrifice foraging opportunities in favour of increased predator avoidance. Under conditions of high or frequent predation risk, such tradeoffs may lead to reduced fitness. Here, we test the pre diction that prey reduce the costs associated with lost opportunities following acute predation threats by exhibiting shortterm compensatory foraging responses. Under seminatural conditions, we exposed female guppies Poecilia reticulate from high and low predation risk sites to one of three levels of acute predation threat （high, intermediate or low concentrations of conspecific alarm cues）. Our results confirm previous reports, demonstrating that guppies from a high predation site were consistently ＇bolder＇（shorter escape latencies） and exhibited graded threatsensitive responses to different simulated threat levels while those from the low predation site were ＇shyer＇ and exhibited nongraded responses. Most importantly, we found that when guppies from low predation sites resumed foraging, they did so at rates significantly lower than baseline rates. However, guppies from high preda tion sites resumed foraging either at rates equal to baseline （in response to low or intemaediate risk stimuli） or significantly in creased relative to baseline rates （in response to high risk stimuli）. Together, these results highlight a complex compensatory be havioral mechanism that may allow prey to reduce the longterm costs associated with predator avoidance [Current Zoology 60 （3）： 323-332, 2014 ].

关键词： Compensatory behaviour Predator-prey interactions Personality Threat-sensitivity Trade-offs