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ELECTRONIC sTATEs AND HYDROGEN EMBRITTLEMENTIN TRANsITION METALs

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Acta Metallurgica sinica(English Letters) 1997年第3期10卷 271-275页

作者： s. Tanimori and s. shimamura(Department of Applied science, Faculty of Engineering, Yamaguchi University, Ube 755, Japan) Yamaguchi Univ Ube Japan

An electronic approach to the mechanism of hydrogen embrittlement in metals is pre-sented and discussed. some problems of the mechanism of hydrogen embrittlement are pointed out from an electronic point of view. Electronic structure calculations in a periodically cleaved or slipped lattice are developed in orker to identofy deformation-sensitive electronic states in the absence of hydrogen. The calculational results are given and discussed for a trunsition metal, Pd. Electronic structure calculations in the presence of hydrogen are outlined and hydrogen embrittlement in transition metals is discussed in terms of electronic states.

关键词： hydrogen embrittlement transition metal electronic structure,electron energy

Demand and deterioration of items per unit time inventory models with shortages using genetic algorithm

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Journal of Management Analytics 2021年第3期8卷 502-529页

作者： sandesh s.Kurade Raosaheb Latpate Department of statistics MES Abasaheb Garware CollegePuneIndia Department of statistics Savitribai Phule Pune UniversityPuneIndia

Inventory management is a crucial task for any *** this paper,we have determined the optimum profit and economical order quantity under variety of assumptions such as the demand per unit time follows either a log-normal or a generalized exponential *** relationship between these two distributions,the proposed models become *** modeling,we consider the expected demand and variable *** these probabilistic assumptions,inventory models are developed for situations like no,complete and partial *** methods are unable to solve these situations under these *** genetic algorithm is proposed to solve these *** order quantity is obtained for maximizing the total profit for the respective demand per unit time distributions.A real-world case study of a deteriorated product is presented to illustrate the procedures of the proposed inventory models.

关键词： backlogging demand per unit time generalized exponential distribution genetic algorithm log-normal distribution variable deterioration

Photoelectrocatrocatalytic hydrolysis of starch by using sprayed ZnO thin films

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Journal of semiconductors 2013年第5期34卷 13-15页

作者： R.T.sapkal s.s.shinde K.Y.Rajpure C.H.Bhosale Electrochemical Materials Laboratory Department of PhysicsShivaji UniversityKolhapur-416004India

： Thin films of zinc oxide have been deposited onto glass/FTO substrates at optimized 400 ℃ by using a chemical spray pyrolysis technique. Deposited films are characterized for their structural, morphological optical and photocatalytic activity by using XRD, an sEM, a UV-vis spectrophotometer, and a PEC single-cell reactor. Films are polycrystalline and have a hexagonal （wurtzite） crystal structure with c-axis （002） orientation growth perpendicular to the substrate surface. The observed direct band gap is about 3.22 eV for typical films prepared at 400 ℃. The photocatalytic activity of starch with a ZnO photocatalyst has been studied by using a novel photoelectrocatalytic process.

关键词： photoelectrocatalysis hydrolysis starch DNsA

Comparison of linear and nonlinear aerodynamic parameter estimation approaches for an unmanned aerial vehicle using unscented Kalman filter

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Journal of Beijing Institute of Technology 2011年第3期20卷 339-344页

作者：李蒙刘莉 s.M.VEREs school of Aerospace Engineering Beijing Institute of Technology school of Engineering sciences University of Southampton

Aerodynamic parameter estimation provides an effective way for aerospace system modeling using measured data from flight tests, especially for the purpose of developing elaborate simulation environments and designing control systems of unmanned aerial vehicle （UAV） with short design cycles and reduced cost. However, parameter identification of airplane dynamics by nonlinear mod- els is complicated because of the noisy and biased sensor measurements. Using linear models for system identification is an alternative way if the fidelity can be guaranteed, as control design procedures are better established in linear systems. This paper considers the application and comparison of linear as well as nonlinear aerodynamic parameter estimation approaches of an UAV using unscented Kalman filter （UKF）. It also highlights the degree of deterioration of the linear model in the UKF identification process. The results show that both the linear and nonlinear methodologies can accurately estimate the control system design. Furthermore, considering loss of accuracy to be negligible, the linear model can be employed for control design of the UAV as presented here.

关键词： unmanned aerial vehicle aerodynamic parameter estimation unscented Kalman filter

Performance effects of feed-borne Fusarium mycotoxins on broiler chickens: Influences of timing and duration of exposure

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Animal Nutrition 2019年第1期5卷 32-40页

作者： Anhao Wang Natacha s.Hogan Department of Animal and Poultry science College of Agriculture and Bioresources University of Saskatchewan Toxicology Centre University of Saskatchewan

In commercial practice, broiler chickens may be exposed to Fusarium mycotoxins either during specific growth stages or throughout the entire production cycle. A 34-day feeding trial was conducted to identify sensitive periods for mycotoxin effects during the growth cycle of broiler chickens. A total of 420 newly-hatched Ross 308 male broilers were randomly assigned to 60 cages with 7 birds/cage. sources of clean wheat(sarium-contaminated wheat(11.4 mg/kg DON)were used to formulate the starter diets(0.41 and 6.62 mg/kg DON) provided from 1 to 21 d of age and the grower diets(0.54 and 7.90 mg/kg DON) provided from 22 to 34 d. Control and DON diets were provided to broilers according to treatments(control, DON 1 to 14 d, DON 15 to 21 d, DON 22 to 34 d and DON 1 to 34 d). Birds were monitored daily for morbidity or mortality. Broiler growth performance(body weight, average daily gain, average daily feed intake and feed to gain ratio) was measured *** of duodenum, jejunum and ileum were collected at 21 and 34 d and morphometric parameters(villus height, crypt depth, villus width, muscularis thickness and villi:crypt ratio) were measured. Birds fed the DON starter diet during the first 14 d did not exhibit any changes in growth performance;however, growth performance was suppressed in birds fed DON-contaminated diets during the grower period(22 to 34 d). At 34 d, birds that received the DON grower diet(DON 22 to 34 d and DON 1 to 34 d)were lighter(1,433 vs. 1,695 g) than birds fed the control diet. Feed to gain ratio was higher in birds fed the DON grower diet from 22 to 28 d(1.77 vs. 1.56) and 28 to 34 d(2.24 vs. 1.85) compared with corresponding controls. These results suggest that providing older broiler chicks(22 to 34 d) feed contaminated with Fusarium mycotoxins(specifically DON) may result in production losses. Histopathological analysis of the ileum region revealed that birds provided the DON diets throughout the

关键词： Deoxynivalenol Chicken sensitive period Feed contamination Intestine

A Hybrid Deep Learning Model for Real Time Hand Gestures Recognition

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Intelligent Automation & soft Computing 2023年第4期36卷 1105-1119页

作者： s.Gnanapriya K.Rahimunnisa Department of Information Technology Easwari Engineering CollegeChennai600089India Department of Electronics and Communication Engineering Easwari Engineering CollegeChennai600089India

The performance of Hand Gesture Recognition(HGR)depends on the hand *** helps in the recognition of hand gestures for more accuracy and improves the overall performance compared to other existing deep neural *** crucial segmentation task is extremely complicated because of the background complexity,variation in illumination *** proposed mod-iﬁed UNET and ensemble model of Convolutional Neural Networks(CNN)undergoes a two stage process and results in proper hand gesture ***ﬁrst stage is segmenting the regions of the hand and the second stage is ges-ture identiﬁ*** modiﬁed UNET segmentation model is trained using resized images to generate a cost effective semantic segmentation *** Central Processing Unit(CPU)utilization and training time taken by these models with respect to three public benchmark datasets are also *** is carried out with the ensemble learning model consisting of EfﬁcientNet B0,Efﬁ-cientNet B4 and ResNet *** on NUs hand posture dataset-II,OUHANDs and HGRI benchmark datasets show that our architecture achieves a maximum recognition rate of 99.07%through semantic segmentation and the Ensemble learning model.

关键词： Convolutional neural networks EfﬁcientNet ensemble learning ResNet semantic segmentation UNet

Fuzzy Reputation Based Trust Mechanism for Mitigating Attacks in MANET

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Intelligent Automation & soft Computing 2023年第3期35卷 3677-3692页

作者： s.Maheswari R.Vijayabhasker Department of Electronics and Communication Engineering Anna University Regional CampusCoimbatore641046India

Mobile Ad-hoc Networks(MANET)usage across the globe is increas-ing by the *** a node’s trust value has signiﬁcant advantages since such network applications only run efﬁciently by involving trustable *** trust values are estimated based on the reputation values of each node in the network by using different ***,these mechanisms have various challenging issues which degrade the network ***,a novel Quality of service(Qos)Trust Estimation with Black/Gray hole Attack Detection approach is proposed in this research ***,the Qos-based trust estimation is proposed by using a Fuzzy logic *** trust value of each node is estimated by using each node’s reputation values which are deter-mined based on the fuzzy membership function values and utilizing Qos para-meters such as residual energy,bandwidth,node mobility,and *** mechanism prevents only the black hole attack in the network during ***,the gray hole attacks are not identiﬁed which in turn increases the pack-et drop rate signiﬁ***,the gray hole attack is also detected based on the Kullback-Leibler(KL)divergence method used for estimating the statistical *** Qos metrics are considered to prevent the gray hole attack,such as packet loss,packet delivery ratio,and delay for each ***,the proposed mechanism prevents both black hole and gray hole attacks ***-ly,the simulation results show that the effectiveness of the proposed mechanism compared with the other trust-aware routing protocols in MANET.

关键词： Mobile ad-hoc network trust estimation blackhole grayhole attack fuzzy logic qos parameters kullback-leibler divergence

DEPTH-AVERAGED 2-D CALCULATION OF FLOW AND sEDIMENT TRANsPORT IN CURVED CHANNELs

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International Journal of sediment Research 2004年第4期19卷 241-257页

作者： sam s. Y. WANG Director Distinguished Professor Ms 38677 National Center for Computational Hydroscience and Engineering The University of Mississippi UsA

The helical flow significantly affects the flow, sediment transport and morphological evolution in curved channels. A semi-empirical formula is proposed to determine the cross-stream distribution of the helical flow intensity in the developed regions of a channel bend. It is then used to evaluate the dispersion terms in the depth-averaged 2-D momentum equations and suspended-load transport equation as well as the bed-load transport angle, thus enhancing the depth-averaged 2-D model to account for the effect of helical flow. The tests in several experimental and field cases show that the enhanced depth-averaged 2-D model can much more reasonably predict the shifting of main flow from inner bank to outer bank, the erosion along outer bank and deposition along inner bank than the depth-averaged 2-D model without considering this effect.

关键词： secondary flow Channel bends Dispersion Unsteady flow sediment transport Two- dimensional model Finite volume method

Alginate nanobeads interspersed fibrin network as in situ forming hydrogel for soft tissue engineering

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Bioactive Materials 2018年第2期3卷 194-200页

作者： s.Deepthi R.Jayakumar Centre for Nanosciences and Molecular Medicine Amrita UniversityKochi682041India

Hydrogels are a class of materials that has the property of injectability and in situ gel *** property of hydrogels is manipulated in this study to develop a biomimetic bioresorbable injectable system of alginate nanobeads interspersed in fibrin *** nanobeads developed by calcium cross-linking yielded a size of 200e500 *** alginate nanobeads fibrin hydrogel was formed using dual syringe *** of the in situ injectable hydrogel was done by sEM,FTIR and *** developed hydrogel showed mechanical strength of 19 kPa which provides the suitable compliance for soft tissue *** studies using human umbilical cord blood derived mesenchymal stem cells showed good attachment,proliferation and infiltration within the hydrogel similar to fibrin *** developed in situ forming hydrogel could be a suitable delivery carrier of stem cells for soft tissue regeneration.

关键词： Alginate nanobeads Fibrin hydrogel soft tissue engineering