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Neural Regeneration Research 2025年第6期20卷 1699-1700页

作者： Seyed Mojtaba Hosseini Soheila Karimi-Abdolrezaee Department of Physiology and Pathophysiology Spinal Cord Research CentreRady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada manitoba Multiple Sclerosis Research Center WinnipegMBCanada Children Hospital Research Institute of manitoba WinnipegMBCanada

Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).

关键词： peroxidation Fischer injury

An experimental study on the effects of physical,mechanical,and electrochemical properties of natural cohesive soils on critical shear stress and erosion rate

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International Journal of Sediment Research 2016年第01期31卷 1-15页

作者： Navid Kimiaghalam Shawn P.Clark Habib Ahmari Department of Civil Engineering University of Manitoba Water Resources Department Manitoba Hydro

The field of cohesive sediment erosion is still not fully understood,in large part due to the many soil parameters that affect cohesive sediment *** this study several undisturbed natural soil samples were taken from different river banks in manitoba,*** samples mainly contained clay and silt with 24-94%clay content,thus the study covered a wide range of cohesive *** each sample13 different physical,mechanical,and electrochemical properties were *** shear stress of erosion and erosion rate were quantified using an Erosion Measurement Device(EMD).Stepwise regression was used to find the variables most significantly correlated to critical shear stress and erosion rate,which led to the development of a new empirical equation to estimate the critical shear stress of cohesive *** was found that the critical shear stress is highly correlated with cohesion,while both cohesion and sodium adsorption ratio(SAR)had significant influence on the erosion rate.

关键词： Cohesive sediment Critical shear stress Erosion rate

Brain age estimation:premise,promise,and problems

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Neural Regeneration Research 2025年第8期20卷 2313-2314页

作者： Jarrad Perron Ji Hyun Ko Graduate Program in Biomedical Engineering Price Faculty of EngineeringUniversity of ManitobaWinnipegMBCanada PrairieNeuro Research Centre Kleysen Institute for Advanced MedicineHealth Sciences CentreWinnipegMBCanada Department of Human Anatomy and Cell Science Rady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada

Premise:The com bined effects of modern healthcare practices which prolong lifespan and declining birthrates have created unprecedented changes in age demographics worldwide that are especially pronounced in Japan,South Korea,Europe,and North *** old age is the most significant predictor of dementia,global healthcare systems must rise to the challenge of providing care for those with neurodegenerative disorders.

关键词： estimation providing birth

New experimental study on the DC flashover voltage of polymer insulators:combined effect of surface charges and air humidity

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High Voltage 2019年第4期4卷 316-323页

作者： Mohammed Amer Jeff Laninga William McDermid David R.Swatek Behzad Kordi Department of Electrical and Computer Engineering University of Manitoba75 Chancellor's CircleWinnipegManitobaCanada R3T 5V6 manitoba hydro WinnipegManitobaCanada R3M 3T1

This research provides conclusions that can partially cover the lack of knowledge related to the effects of ambient atmospheric conditions on DC electric power *** polymer insulating materials are used for completing this research *** a climate chamber,the relative humidity is controlled and adjusted from 20%to 80%***,the samples are charged with positive or negative charges by applying±20 kV to the corona-generating ring of *** surface potential is measured using an electrostatic voltmeter and is converted into surface charge density later by applying the probe response matrix *** pre-charged samples are then stressed with high-voltage negative or positive DC values inside the climate chamber over a range of controlled values of the surrounding air humidity until flashover takes *** space charges,which can drift in the air gap to reach the solid surface,are highly affected by the level of the relative humidity of the surrounding ***,increasing humidity results in a reduction of the DC flashover inception voltage and a shorter time to flashover regardless of the voltage ***,the positive or negative flashover inception voltage of both materials increases with pre-deposited negative charges while it decreases with pre-deposited positive charges.

关键词： charges flash humidity

THE EFFECT OF OCCUPANCY ON ELECTRICITY USE IN THREE CANADIAN SCHOOLS

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Journal of Green Building 2018年第1期13卷 95-112页

作者： Mohamed Ouf Mohamed H.Issa Phil Merkel Panos Polyzois Department of Civil Engineering University of Manitoba15 Gillson StreetWinnipeg MB R3T 5V6 Canada Customer Engineering Department Manitoba Hydro

Through building performance simulations, previous studies showed the effect of occupants on buildings’ energy consumption. To further demonstrate this effect using empirical evidence, this study analyzed the effect of occupancy on real-time electricity consumption in three case-study schools in manitoba. Within each school, one classroom as well as the gymnasium were sub-metered to collect real-time electricity consumption data at half-hourly intervals. The study focused on electricity consumption for lighting and plug loads, which make up 30% of energy consumption in Canadian commercial and institutional buildings. A comprehensive method was developed to investigate energy-related occupant behaviour in the sub-metered spaces using four different tools simultaneously: 1) gymnasium bookings after school hours over a four-month period, 2) half-hourly observations of lighting and equipment use in the sub-metered spaces in each school over a two-week period, 3) a daily survey administered to teachers in the sub-metered classrooms over a two-week period, and 4) occupancy and light sensors to evaluate actual recorded occupancy and light use durations over a four-month period. Results showed that recorded occupancy durations over a 4-month period only explained less than 10% of the variations in classrooms’ lighting electricity consumption, meaning that lights may have been used frequently while classrooms were unoccupied. Results also showed the differences in gymnasiums’ electricity consumption were still statistically significant between the three schools, even after school hours and when the gymnasiums were not used or booked for other activities. This study is the first to provide in-depth evaluation of the effect of occupancy on electricity consumption in Canadian schools.

关键词： Occupancy energy efficiency school buildings real-time electricity monitoring

高压直流换流站穿墙套管的局部放电在线测量(英文)

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高电压技术 2011年第11期37卷 2636-2642页

作者： Nathan D.Jacob William M.McDermid Behzad Kordi Department of Electrical & Computer Engineering University of ManitobaWinnipegCanada Insulation Engineering & Testing Department Manitoba HydroWinnipegCanada

An online partial discharge(PD) measurement performed on a high voltage direct current(HVDC) wall bushing successfully identified the presence of internal *** wall bushing is a sulfur hexafluoride gas-insulated bushing,rated for 500 kV dc and terminated on a thyristor-controlled HVDC converter *** measurement of PD within the HVDC station environment is particularly challenging due to the high levels of electromagnetic noise caused by thyristor switching events and external air-corona from the neighboring high-voltage *** additional challenge is the""mixed"voltage stress on the bushing insulation,which has both ac and dc high-voltage *** are also fast transients during the firing of thyristors in the HVDC conversion process that cause added stress to the *** a result,the analysis and interpretation of PD data for HVDC equipment is more complex;PD pulses may occur in response to the ac,dc,or switching transient voltage *** this paper,an online PD measurement strategy for noise filtering and isolation of PD sources within the bushing are *** PD measurement data is plotted on a phase-resolved diagram where the line supply power cord voltage was used as a reference. The phase-resolved diagram appears to suggest that the fast transients,caused during switching,trigger some PD *** were also performed with the aid of a modern PD measurement instrument having noise separation *** findings from the online PD measurements are verified with physical evidence,found after the bushing was removed from service,suggested internal PD had occurred inside the bushing.

关键词： partial discharge(PD) electrical insulation high voltage direct current(HVDC) converters SF6 electromagnetic interference electromagnetic coupling

Performance of IEEE 802.15.4 Clusters with Power Management and Key Exchange

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Journal of Computer Science & Technology 2008年第3期23卷 377-388页

作者： Fereshteh Amini Moazzam Khan Jelena Mii Hossein Pourreza Department of Computer Science University of ManitobaWinnipegManitobaCanada

The IEEE 802.15.4 specification is a recent low data rate wireless personal area network standard. While basic security services are provided for, there is a lack of more advanced techniques which are indispensable in modern personal area network applications. In addition, performance implications of those services are not known. In this paper, we describe a secure data exchange protocol based on the ZigBee specification and built on top of IEEE 802.15.4 link layer. This protocol includes a key exchange mechanism. We assume that all nodes are applying power management technique based on the constant event sensing reliability required by the coordinator. Power management generates random sleep times by every node which in average fairly distributes the sensing load among the nodes. Key exchange is initiated by a cluster coordinator after some given number of sensing packets have been received by the coordinator. We develop and integrate simulation model of the key exchange and power management technique into the cluster＇s reliable sensing function. We evaluate the impact of security function and its periodicity on cluster performance.

关键词： IEEE 802.15.4 security activity management simulation

Overview of SPH-ALE applications for hydraulic turbines in ANDRITZ hydro

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Journal of hydrodynamics 2018年第1期30卷 114-121页

作者： M.Rentschler J.C.Marongiu M.Neuhauser E.Parkinson R&D Department ANDRITZ Hydro

Over the past 13 years, ANDRITZ hydro has developed an in-house tool based on the SPH-ALE method for applications in flow simulations in hydraulic turbines. The initial motivation is related to the challenging simulation of free surface flows in Pelton turbines, where highly dynamic water jets interact with rotating buckets, creating thin water jets traveling inside the housing and possibly causing disturbances on the runner. The present paper proposes an overview of industrial applications allowed by the developed tool, including design evaluation of Pelton runners and casings, transient operation of Pelton units and free surface flows in hydraulic structures.

关键词： Pelton turbine two-phase folw smoothed particle hydrodynamics(SPH) arbitrary Lagrange-Euler(ALE)

裂纹和污秽瓷绝缘子的电磁场辐射信号特征(英文)

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高电压技术 2011年第11期37卷 2649-2654页

作者： Ehsan Azordegan David R Swatek Behzad Kordi Department of Electrical and Computer Engineering University of ManitobaWinnipegMBCanada Insulation Engineering and Testing Department Manitoba HydroWinnipegMBCanada

Porcelain cap and pin insulators are by far the most popular suspension insulators in high voltage(HV) distribution networks all around the *** and condition monitoring of HV insulators is also very important to the utility companies because of the critical and vital role that they play in distribution *** terms of safety, practicality and ease of use,remote detection methods are more popular among the line technicians.A new remote condition assessment method based on electromagnetic radiations from porcelain insulators is presented in this paper. In a lab environment,a string of two porcelain insulators is energized by a 45 kV *** radiations due to the partial discharge activities inside the porcelain insulator are captured by passive sensors and antennas. Two cases of defective insulators on a two insulator string are studied *** first case focuses on the effect of contaminated porcelain shells on radiation signature of partial discharges.A polluted porcelain shell with ESDD level of 0.03 mg/cm^2 was first *** second case studies the effect of cracks of an intentionally-cracked porcelain shell. The cracked insulator is also tested on a two insulator *** compare the partial discharge radiation signature of different faulty insulators,phase resolved graphs were *** electromagnetic radiated signature of a polluted insulator and a cracked insulator was calculated and compared using phase resolved graphs.

关键词： partial discharge electromagnetic radiation contamination high voltage porcelain insulator condition assessment phase resolved graph

Analyzing hydro abrasive erosion in Kaplan turbine:A case study from India

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Journal of hydrodynamics 2016年第5期28卷 863-872页

作者： Anant Kr.RAI Arun KUMAR Alternate hydro Energy Centre IIT Roorkee

Sediment flow through hydro turbine causes erosion of hydraulic components resulting in drop of turbine efficiency, parti- cularly in hydropower plants of the Himalayan region. The measurement of erosion and monitoring of sediment flow in turbine are major concerns in erosion study. Attempts have been made to study erosion mainly in Pelton and Francis turbines. In this study, a simple and effective method has been presented to measure erosion in a Kaplan turbine of a run-of-river scheme Chilla hydropower plant in foothills of Himalaya. Recent techniques were used to measure sediment parameters like concentration, size, shape and mineral content. A standard erosion model is applied to estimate the erosion in Kaplan turbine blade, runner chamber and draft tube cone. A calibration factor has been proposed to apply the erosion model for site specific conditions. It has been found that the outer trailing edges of the turbine blade and upper rtmner chamber are most erosion prone zones. Sediment analysis revealed that effective operation can reduce erosion in turbine components. The estimated erosion values from model are found to be consistent with measu- red values. Finally, suggestions for design improvements and effective operation of erosion affected hydropower plants are given.

关键词： turbine sediment erosion measurement IEC 62364 hydropower