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The assessment of heavy metal pollution in river sands of Jalingo,Nigeria using magnetic proxy parameters,pollution,and ecotoxicological indices

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Acta Geochimica 2022年第6期41卷 1083-1103页

作者： maxwell O.Kanu Augustine A.Abong Department of Physics Faculty of ScienceTaraba State UniversityP.M.B.1167JalingoTaraba StateNigeria Department of Physics Faculty of ScienceCross River University of TechnologyP.M.B.1123CalabarNigeria

The measurement of environmental magnetic properties and metal contents of sands from Nukkai(NKR),Mayo-Gwoi(RMYG)and Lamurde(LR)rivers located in Jalingo,Nigeria are *** seek to determine the extent of anthropogenic impact on the river sands using magnetic-proxy-parameters,pollution and ecotoxicological indices and multivariate *** of magnetic susceptibilityχ,frequency-dependentsusceptibilityχfd%,anhystericremanent magnetization,isothernal remanent magnetization and X-ray fluorescence were *** average values of theχ(in×10^(-8)m^(3)kg^(-1))were 24.53,12.76 and 39.27 for NKR,RMYG and LR sites respectively,implying that the magnetic minerals in the sands were mostly *** meanχfd%value of 2.64%,4.85%and 3.53%for NKR,RMYG and LR respectively suggest that the study area was dominated by multi-domain magnetic grain *** value of the S-ratio is~1 in all river samples,suggesting that low coercivity magnetic minerals(e.g.,magnetite)dominated the *** mean concentrations of Ti,Zr,Sn,ba and Pb were higher than the background values in the studied *** the estimated pollution indices puts the level of pollution of the river sands between low and moderate pollution with Sn,ba and Pb as the elements of *** sources of metal contents such as fertilizers,pesticides,waste dumps and vehicular sources *** *** positive correlations between magnetic parameters(particularly,SIRM)and some heavy metals and pollution/ecotoxicological indices were obtained,showing that magnetic methods could be used as a geochemical proxy for pollution assessment.

关键词： Magnetic susceptibility Ecotoxicological risk index Pollution index Heavy metals pollution River

Accuracy of common stem volume formulae using terrestrial photogrammetric point clouds:a case study with savanna trees in benin

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Journal of Forestry Research 2021年第6期32卷 2415-2422页

作者： Hospice A.Akpo Gilbert Atindogbe maxwell C.Obiakara Arios b.Adjinanoukon Madai Gbedolo Noel H.Fonton Laboratoire d’Etudes et de Recherche en Statistiques et biométrie Appliquee FSAUniversite D’Abomey-Calavi01 BP 526CotonouBenin Ecology Unity Department of BotanyUniversity of IbadanIbadan 20084Nigeria

Recent applications of digital photogrammetry in forestry have highlighted its utility as a viable mensuration ***,in tropical regions little research has been done on the accuracy of this approach for stem volume *** this study,the performance of Structure from Motion photogrammetry for estimating individual tree stem volume in relation to traditional approaches was *** selected 30 trees from five savanna species growing at the periphery of the W National Park in northern benin and measured their circumferences at different heights using traditional tape and *** volumes of sample trees were estimated from the measured circumferences using nine volumetric formulae for solids of revolution,including cylinder,cone,paraboloid,neiloid and their respective *** tree was photographed and stem volume determined using a taper function derived from tri-dimensional stem *** reference volume was compared with the results of formulaic *** stem profiles were further decomposed into different portions,approximately corresponding to the stump,butt logs and logs,and the suitability of each solid of revolution was assessed for simulating the resulting *** volumes calculated using the fustrums of paraboloid and neiloid formulae were the closest to reference volumes with a bias and root mean square error of 8.0%and 24.4%,*** closely resembled fustrums of a paraboloid and a *** stem portions assumed different solids as follows:fustrums of paraboloid and neiloid were more prevalent from the stump to breast height,while a paraboloid closely matched stem shapes beyond this ***,a more accurate stem volumetric estimate was attained when stems were considered as a composite of at least three geometric solids.

关键词： Structure from motion photogrammetry Point cloud data Stem volume Savanna species benin

Offshoring and Reshoring： The Roles of Incomplete Contracts and Relative bargaining Power

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2018年第1期13卷 32-51页

作者： Ngo Van Long maxwell Tuuli Department of Economics McGill University Montreal Quebec H3A 2T7 Canada Peter b. Gustavson School. of business University of Victoria Victoria BC V8P 5C2 Canada

This paper demonstrates that an increase in bargaining power of Northern firms relative to that of their Southern contractors can trigger reshoring if the North- South wage differential is moderate, such that only industries with a high share of unskilled labor find outsourcing profitable. However, such an increase in Northern bargaining power can increase offshoring if the wage differential is so high that even industries with a low share of unskilled labor also offshore.

关键词： incomplete contracts bargaining power offshoring reshoring

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

Optimization and kinetic studies for enzymatic hydrolysis and fermentation of colocynthis vulgaris Shrad seeds shell for bioethanol production

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Journal of bioresources and bioproducts 2021年第1期6卷 45-64页

作者： Igwilo Christopher Nnaemeka Egbuna Samuel O Onoh maxwell I Asadu OChristain Onyekwulu Chinelo S Department of Science Laboratory Technology Federal College of AgricultureP.M.BIshiaguEbonyi StateNigeria Department of Chemical Engineering Enugu State University of Science and Technology (ESUT)Nigeria Gregory University Uturu PMb 1012 Abia State Nigeria

The key process parameters for the hydrolysis and fermentation of Colocynthis vulgaris Shrad seeds shell(CVSSS)were optimized using the box-behnken Design(bbD)of Response Surface Methodology(RSM).Kinetic study was also carried *** proximate analysis of the CVSSS was done by the method of the Association of Organic and Applied Chemistry(AOAC).Enzymatic hydrolysis was experimented by using Aspergillus Niger as a crude enzyme isolated from soil at sawdust dump site and screened for cellulosic *** that affected the hydrolysis of the CVSSS were screened by using the Greco-Latin square design of ***,for Saccharomyces cerevisiae,factors that affected the fermentation of the CVSSS were screened by using the same Greco-Latin square design of ***,the result of the proximate analysis revealed that the CVSSS had 73.54%cellulose which could be converted to *** was established that temperature,pH and time had significant effect on hydrolysis,while the optimum results were obtained at 46.8℃,3.32 d,5.68 and 59.87%for temperature,time,pH and glucose yield,***,yeast dosage,pH and time had significant effect on fermentation,while the optimum results from optimization were found to be 33.58℃,7.0,3.55 d,1.65 g per 50 mL and 25.6%for temperature,pH,time,yeast dosage and ethanol yield,*** kinetics of both the enzymatic hydrolysis and fermentation agreed with the Michealis-Menten kinetic model with the correlation coefficients(R^(2))of 0.9708 and 0.8773,***,from the error analysis,the experimental and predicted values had a very good relationship as described by Michaelis-Menten model.

关键词： Ethanol Melon(Egusi)seed shell Hydrolysis Fermentation Optimization Kinetics

Effect of Nutrient Restriction on Social Transmission of Food Preferences Depends on Nutrient and Species

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Journal of behavioral and brain Science 2014年第12期4卷 590-601页

作者： Darryl J. Mayeaux maxwell b. Wallace Anne M. Young Department of Psychology St. Bonaventure University New York USA

For omnivores to determine whether an unfamiliar item is an appropriate food, they could rely on personal information from sampling it themselves or rely on less risky observation of whether other individuals eat the item. Availability of information about food from social companions in group-living species is one of the benefits of group life. Adults of solitary-living species, however, seem typically less likely to rely on social information about food choice. If an individual faced a nutritional deficit, it would seem to increase the value of public information. This study addresses whether dietary restriction from certain nutrients (sodium, potassium, protein, carbohydrates) affects reliance on information about food from conspecifics. Without nutrient restriction, group-living Norway rats (Rattus norvegicus) preferred the diet that they smelled on the breath of a conspecific demonstrator, but solitary-living Syrian hamsters (Mesocricetus auratus) avoided it. Protein restriction yielded similar results as measured one hour into a diet choice test. Potassium restriction, however, reversed the pattern: rats avoided the demonstrator’s diet but hamsters preferred it. Clearly, the valence of social information depended on the nutrient from which individuals were restricted and the species under study. This could be related to the contrasting social organization that members of each species generate. Neither species relied on social information about the availability of a nutrient from which they were restricted if they could taste that nutrient for themselves (sodium, carbohydrates).

关键词： Social Learning Dietary Preference Nutrient Restriction

Analyzing Virtual World Region Fidelity on Scalability and Simulation Performance

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Open Journal of Modelling and Simulation 2015年第3期3卷 126-135页

作者： Sean C. Mondesire Jonathan Stevens Rebecca Leis Douglas b. maxwell US Army Research Laboratory Orlando FL USA Institute for Simulation and Training University of Central Florida Orlando FL USA

Virtual world simulation offers tremendous potential opportunities to improve, and optimize, individual and collective echelon training for the military. The US Army Research Laboratory (ARL) Military Open Simulator Enterprise Strategy (MOSES) project’s charter is to investigate simulation-based training technology for use in military specific training domains. Of particular interest are attributes of virtual worlds such as geographically distributed large-scale trainee support. We have initiated a series of experiments to determine appropriate benchmarks for simulator performance and to determine appropriate independent variables in order to create a robust predictive model that will enable virtual world training scenario designers to calculate, a priori, the number of trainees that may synchronously operate in a virtual world. The present paper’s purposes were to determine the effect that virtual world region fidelity had on server performance and determine whether this independent variable would be appropriate for inclusion into our predictive model. We found that region fidelity had a statistically significant effect on the simulator’s processor memory usage but had no significant effect on the simulator’s vertical scalability, CPU usage nor network performance. In this paper, we discourse on the purpose of this research, our experimental methodology and results, and discuss the significance of our findings.

关键词： Region Fidelity Vertical Scaling Virtual World Simulation Performance Analysis Distributed Simulation

时间域瞬变电磁法中心方式全程视电阻率的数值计算

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地球物理学报 2003年第5期46卷 697-704页

作者：白登海 maxwell A Meju 卢健王立凤何兆海中国地震局地质研究所北京100029 Department of Environmental Science Lancaster University 大连理工大学电信学院大连116023

给出了一种时间域瞬变电磁法视电阻率的数值计算方法 ,利用该方法可以容易地求出中心方式的全程视电阻率 .根据中心方式磁场垂直分量时间变化率 bz T的核函数Y′(Z)的表现特征 ,以参数Z把整个瞬变过程分为早期阶段 (Z >1.6 )、早期到... 详细信息

给出了一种时间域瞬变电磁法视电阻率的数值计算方法 ,利用该方法可以容易地求出中心方式的全程视电阻率 .根据中心方式磁场垂直分量时间变化率 bz T的核函数Y′(Z)的表现特征 ,以参数Z把整个瞬变过程分为早期阶段 (Z >1.6 )、早期到晚期的转折点 (Z =1.6 )和晚期阶段 (Z bz 的核函数Y(Z)是参数Z的单值函数 ,但同样存在一个从早期到晚期的转折点Z =1.6 ,转换点两边仍然可以得到一条早期曲线和一条晚期曲线 .在数值计算中 ,当迭代步长ΔZ <0 .0 0 5Z时 ,视电阻率的相对误差小于 0 .5 % .理论模型和实际数据计算表明 ,与早期和晚期近似值比较 ,全程视电阻率具有更高的精度和分辨率 .

关键词：瞬变电磁法数值计算中心方式迭代步长全程视电阻率

The glutamate metabotropic receptor 5(GRM5)gene is associated with beef cattle home range and movement tortuosity

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Journal of Animal Science and biotechnology 2023年第1期14卷 72-87页

作者： Cristian A.Moreno Garcia Huitong Zhou David Altimira Robyn Dynes Pablo Gregorini Sadeepa Jayathunga Thomas M.R.maxwell Jonathan Hickford Department of Agricultural Sciences Faculty of Agriculture and Life SciencesLincoln UniversityPO Box 85084Lincoln 7647New Zealand. Exertion Games Lab 8 Scenic BoulevardClaytonVictoria 3800Australia. AgResearch Limited Lincoln Research CentreCnr Springs Road and Gerald StreetLincoln 7674New Zealand. Scion Tītokorangi Drive(formerly Long Mile Rd)Rotorua 3010New Zealand.

background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating *** this study,we investigated for first time the genetic variation within a candidate‘grazing gene',the glutamate metabotropic receptor 5 gene(GRM5),and tested associations between variation in that gene and variation in grazing personality behaviours(GP-behaviours)displayed by free-ranging cows during winter grazing in the steep and rugged rangelands of New *** beef cows(n=303,from 3 to 10 years of age)were tracked with global positioning system(GPS)and,with 5-minutes(min)relocation frequency,various GP-behaviours were *** included horizontal and vertical distances travelled,mean elevation,elevation range,elevation gain,slope,home range and movement tortuosity,variously calculated using daily relocation trajectories with repeated measurements(i.e.,7 to 24 days(d))and satellite-derived digital elevation models(DEM).The different GP-behaviours were fitted into mixed models to ascertain their associations with variant sequences and genotypes of ***:We discovered three GRM5 variants(A,b and C)and identified the six possible genotypes in the cattle *** mixed models revealed that A was significantly associated with elevation range,home range and movement ***,GRM5 genotypes were associated(Pbehaviour models were improved by correcting for cow age-class as a fixed *** analysis of GP-behaviours averaged per cow age-class suggests that grazing personality is fully established as beef cows reached 4 years of *** range and movement tortuosity were not only associated with GRM5 variation,but also negatively correlated with each other(r=-0.27,P<0.001).Conclusions:There se

关键词： Animal personality breeding programmes Genetic associations Grazing distribution Grazing patterns Steep and rugged terrain