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A Fault Detection Method for Electric Vehicle Battery System Based on Bayesian Optimization SVDD Considering a Few Faulty Samples

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Energy Engineering 2024年第9期121卷 2543-2568页

作者： Miao Li Fanyong Cheng Jiong yang Maxwell mensah Duodu Hao Tu School of Electronics and Electrical Engineering Anhui Polytechnic UniversityWuhu241000China

Accurate and reliable fault detection is essential for the safe operation of electric *** vector data description(SVDD)has been widely used in the field of fault ***,constructing the hypersphere boundary only describes the distribution of unlabeled samples,while the distribution of faulty samples cannot be effectively described and easilymisses detecting faulty data due to the imbalance of sample ***,selecting parameters is critical to the detection performance,and empirical parameterization is generally timeconsuming and laborious and may not result in finding the optimal ***,this paper proposes a semi-supervised data-driven method based on which the SVDD algorithm is improved and achieves excellent fault detection *** incorporating faulty samples into the underlying SVDD model,training deals better with the problem of missing detection of faulty samples caused by the imbalance in the distribution of abnormal samples,and the hypersphere boundary ismodified to classify the samplesmore *** Bayesian Optimization NSVDD(BO-NSVDD)model was constructed to quickly and accurately optimize hyperparameter *** the experiments,electric vehicle operation data with four common fault types are used to evaluate the performance with other five models,and the results show that the BO-NSVDD model presents superior detection performance for each type of fault data,especially in the imperceptible early and minor faults,which has seen very obvious ***,the strong robustness of the proposed method is verified by adding different intensities of noise in the dataset.

关键词： Fault detection vehicle battery system lithium batteries fault samples

Petrology and Geochemical Relationship of Birimian Gabbro-Diorite-Granodiorite Dykes in Basaltic Rocks at Butre Area, SW Ghana

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Journal of Geoscience and Environment Protection 2024年第2期12卷 107-130页

作者： Victor Graham George mensah Tetteh Department of Geological Engineering University of Mines and Technology Tarkwa Ghana

Granitoids at Butre area, south-western part of the Birimian of Ghana are gabbro to granodiorite which intruded comagmatic basalt and andesite of volcanic island arc setting. Differentiation was from probably mantle fractionates on tholeiitic basalt trend through gabbro-diorite and granodiorite. yet, the diorite intruded into the volcanic rocks prior to plate collision. Plagioclase feldspars of labradorite to andesine compositions (An52 - An48), amphibole and pyroxene are in association with accessory tourmaline, actinolite, apatite and garnet. Relict amphibolite facies metamorphism is preserved in xenoliths in gabbro to diorite which show greenschist facies. Generally, plagioclase is partially altered to fine quartz, sericite and carbonates whereas chlorite and epidote are of amphibole alteration. These alterations are typical of carbonatisation but diorite shows partial carbonate-sericite alteration. Alterations followed granodiorite emplacement. Arsenopyrite and pyrite accompanied emplacement of diorite and granodiorite respectively while amphibolite facies metamorphism introduced magnetite;haematite and pyrrhotite accompanied greenschist facies metamorphism. Earlier opaque minerals possibly were consumed to form later minerals. All the rocks are LREE depleted (La/Sm chondrite normalised ratios of basalt = 0.8 to 2.5;andesite = 2.03;diorite = 1.95 to 3.1;gabbro-diorite = 0.9 to 2.05;granodiorite = 1.66);diorite, basalt and andesite are fairly enriched in HREE. Enrichment of FeOT, MgO, SiO2, CaO and depletion of TiO2, K2O and Zr might be linked with carbonitisation, sericitisation, chloritisation, silicification and sulphidation linked to gold mineralisations in the Birimian of Ghana.

关键词： Granitoids Petrography Alteration Metamorphism Geochemistry Butre

Investigation of Acoustomagnetoelectric Effect in Bandgap Graphene by the Boltzmann Transport Equation

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World Journal of Condensed Matter Physics 2024年第1期14卷 10-20页

作者： Raymond Edziah Samuel S. Bentsiefi Kwadwo Dompreh Anthony Twum Emmanuel Kofi Amewode Patrick mensah-Amoah Ebenezer T. Tatchie Cynthia Jebuni-Adanu Samuel y. mensah Department of Physics University of Cape Coast Cape Coast Ghana Department of Physics Education University of Education Winneba Ghana

We study the acoustomagnetoelectric (AME) effect in two-dimensional graphene with an energy bandgap using the semiclassical Boltzmann transport equation within the hypersound regime, (where represents the acoustic wavenumber and is the mean free path of the electron). The Boltzmann transport equation and other relevant equations were solved analytically to obtain an expression for the AME current density, consisting of longitudinal and Hall components. Our numerical results indicate that both components of the AME current densities display oscillatory behaviour. Furthermore, geometric resonances and Weiss oscillations were each defined using the relationship between the current density and Surface Acoustic Wave (SAW) frequency and the inverse of the applied magnetic field, respectively. Our results show that the AME current density of bandgap graphene, which can be controlled to suit a particular electronic device application, is smaller than that of (gapless) graphene and is therefore, more suited for nanophotonic device applications.

关键词： Boltzmann Transport Equation Acoustomagnetoelctric Effect Surface Acoustic Wave Gapless Graphene Weiss Oscillations

家庭血压远程监测与社区卫生工作者相结合改善血压(LINK-BP)项目的设计与原理

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中华高血压杂志(中英文) 2023年第12期31卷 1284-1284页

作者： commodore-mensah y Liu X Ogungbe O Ibe C Amihere J Mensa M Martin SS Crews D Carson KA Cooper LA Himmelfarb CR 刘青练桂丽

在美国,非洲裔和西班牙裔成人以及生活贫困的人高血压结局的差异仍然存在。家庭血压远程监测与社区卫生工作者相结合改善血压(linked with com-munity health workers to improve blood pressure,LINK-BP)项目是一个多层次的干预项目,...

在美国,非洲裔和西班牙裔成人以及生活贫困的人高血压结局的差异仍然存在。家庭血压远程监测与社区卫生工作者相结合改善血压(linked with com-munity health workers to improve blood pressure,LINK-BP)项目是一个多层次的干预项目,将家庭血压监测与移动健康应用程序、社区卫生工作者的支持以及初级保健实践中的血压测量培训相结合,

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Existence of Solutions of a Convolution Integral Equation

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Journal of Applied Mathematics and Physics 2024年第5期12卷 1835-1847页

作者： Henry Otoo Benjamin Dadzie mensah Lewis Brew Mathematical Sciences Department University of Mines and Technology Tarkwa Ghana Faculty of Science and Technology University of Silesia in Katowice Sosnowiec Poland

In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined on it. An operator P was assigned to the convolution integral operator which was later expressed in terms of the superposition operator and the nonlinear operator. Given a ball Br belonging to the space L it was established that the operator P maps the ball into itself. The Hausdorff measure of noncompactness was then applied by first proving that given a set M∈ B r the set is bounded, closed, convex and nondecreasing. Finally, the Darbo fixed point theorem was applied on the measure obtained from the set E belonging to M. From this application, it was observed that the conditions for the Darbo fixed point theorem was satisfied. This indicated the presence of at least a fixed point for the integral equation which thereby implying the existence of solutions for the integral equation.

关键词： Volterra Integral Equation Convolution Fixed Point Existence Noncompactness

Antimony, Arsenic and Thallium Bioaccumulation in Asiatic Clam (Corbicula fluminea) Transplanted along the Manadas Creek, Laredo, Texas

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Journal of Environmental Protection 2024年第4期15卷 379-400页

作者： Natasha Garcia Vaughan Thomas Alfred Addo-mensah Department of Biology & Chemistry Texas A&M International University Laredo USA

Manadas Creek is an urban tributary of the Rio Grande that flows past a decommissioned antimony smelter and processing plant. This antimony plant is associated with heavy metal contamination in the creek and still poses a threat to the surrounding aquatic environment. Corbicula fluminea was used to determine bioaccumulation from the water column and sediments in Manadas Creek. The metals arsenic (As), antimony (Sb) and thallium (Tl) were analyzed in the water, sediments, gills, mantle, foot, digestive (DI) tract, gonads and shell of clams being monitored at eight sites between March and August 2013. Sediment, water, and dissected Corbicula fluminea samples from different sites in the Creek were acid-digested and analyzed by Inductively Coupled Plasma Optical Emission Spectroscopy. High levels of antimony (25.88 ug/L;75.96 mg/kg) and arsenic (8.26 ug/L;6.41 mg/kg) in the water and sediments were observed at the site downstream from the smelter. There were no detectable concentrations of arsenic, antimony, or thallium in the shell of C. fluminea. Arsenic and antimony were detected in the tissues of C. fluminea but thallium was not detected. Based on the results, the organotropism for arsenic is DI tract > gills > gonads > foot > mantle > shell and the organotropism for antimony is gills > DI tract > gonads > mantle > foot > shell. This study shows that the Asiatic clam (Corbicula fluminea) is a useful bio-monitor to provide data on the status of metal pollution in Manadas Creek, Laredo, Texas.

关键词： Biomarker Manadas Creek Rio Grande Heavy Metals Corbicula fluminea Biota Sediment Accumulation

An Assessment of Procurement Risks Management Systems in the Public Sector

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Chinese Business Review 2024年第2期23卷 76-86页

作者： Atoapem Frimpong Barimah Joyce-Jael Amoafoa mensah Malaysia University of Science and Technology Petaling JayaMalaysia Kwame Nkrumah University of Science and Technology KumasiGhana

Risk management in public procurement is a critical aspect that needs to be addressed in the public *** studies have been conducted to understand the challenges and factors influencing risk management in public *** studies have explored the importance of risk management principles,the role of political influence,and the need for effective risk assessment and *** research has also highlighted the need for specific risk management mechanisms and tools to be implemented in public procurement *** management reforms in the public sector are essential but often circumvented due to assorted reasons,such as political influence and the emergence of new *** research investigation employs a quantitative research design.A total of 380 questionnaires were recovered from *** study showed that the public sector has a procurement risk management system that is effective,but there may be some areas for improvement in the prequalification process,onboarding process,and support provided to newly onboarded ***,the public sector used some strategies to mitigate and control contract risks during the procurement process,but there were some areas for improvement in the review and lessons learned process,risk mitigation measures,contract monitoring and performance evaluation mechanisms,and communication and documentation ***,the results suggest that there were constraints placed on the risk management strategies currently utilized by professionals working in the public *** constraints include insufficient support and buy-in from senior management and stakeholders,bureaucratic or administrative hurdles,inadequate policies and regulations,insufficient training and skill development opportunities,and insufficient *** study highlights the significance of tackling risk management in the realm of public procurement and offers valuable perspectives on avenues for enhancement,obstacl

关键词： public sector public procurement suppliers risk management strategies

Health behavior outcomes in stroke survivors prescribed wearables for atrial fibrillation detection stratified by age

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Journal of Geriatric Cardiology 2024年第3期21卷 323-330页

作者： Joanne Mathew Jordy Mehawej Ziyue Wang Taylor Orwig Eric Ding Andreas Filippaios Syed Naeem Edith mensah Otabil Alex Hamel Kamran Noorishirazi IrinaRadu Jane Saczynski David D.McManus Khanh-Van Tran Division of Cardiovascular Medicine Department of MedicineUniversity of Massachusetts Chan Medical SchoolLake Avenue NorthWorcesterUSA Department of Internal Medicine Central Michigan UniversityMount PleasantUSA Department of Pharmacy and Health Systems Sciences School of PharmacyNortheastern UniversityBostonUSA Department of Population and Quantitative Health Sciences University of Massachusetts Chan Medical SchoolLake Avenue NorthWorcesterUSA

BACKGROUND Smartwatches have become readily accessible tools for detecting atrial fibrillation(AF).There remains limited data on how they affect psychosocial outcomes and engagement in older *** examine the health behavior outcomes of stroke survivors prescribed smartwatches for AF detection stratified by *** We analyzed data from the Pulsewatch study,a randomized controlled trial that enrolled patients(≥50 years)with a history of stroke or transient ischemic attack and CHA2DS2-VASc≥*** participants were equipped with a cardiac patch monitor and a smartwatch-app dyad,while control participants wore the cardiac patch monitor for up to 44 *** evaluated health behavior parameters using standardized tools,including the Consumer Health Activation Index,the Generalized Anxiety Disorder questionnaire,the 12-Item Short Form Health Survey,and wear time of participants categorized into three age groups:Group 1(ages 50-60),Group 2(ages 61-69),and Group 3(ages 70-87).We performed statistical analysis using a mixedeffects repeated measures linear regression model to examine differences amongst age *** Comparative analysis between Groups 1,2 and 3 revealed no significant differences in anxiety,patient activation,perception of physical health and wear *** use of smartwatch technology was associated with a decrease in perception of mental health for Group 2 compared to Group 1(β=-3.29,P=0.046).CONCLUSION Stroke survivors demonstrated a willingness to use smartwatches for AF ***,among these study participants,the majority did not experience negative health behavior outcomes or decreased engagement as age increased.

关键词： prescribed stratified wear

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Ren-integrable and ren-symmetric integrable systems

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： S y Lou School of Physical Science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is ***-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so *** and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for *** particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable *** examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry

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