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Risks and governance of heavy metals in European soil applied phosphate fertilizers 被引量:1
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作者 Lian-kai Zhang Xiang Liu +5 位作者 Ya-jie Sun Bernd G.Lottermoser Roland Bol Heike Windmann Silvia H.Haneklaus Ewald Schnug 《China Geology》 2025年第3期560-572,共13页
Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of ... Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of the 150 phosphate fertilizers stored at the Institute for Crop and Soil Science in Germany has been conducted,supplemented by previously published data.The elements Cd,Bi,U,Cr,Zn,Tl,As,B,Sb,Ni,and Se are found in higher concentrations in sedimentary derived phosphates compared to igneous derived phosphates.Mineral fertilizers contain more than ten times the amount of U,Cd,B,and As compared to farmyard manure.Principal component analyses(PCA)indicate that U,Cd,Be,and Cr are primarily present in sedimentary derived phosphates and their concentrations are 2 to 10 times higher than those in igneous derived phosphates.Regarding heavy metal contamination,over 1000 potential combinations were identified;36% of these were significant but weak(>0.1).It is estimated that approximately 707 t of uranium enter farmland annually through the application of mineral phosphate fertilizers in European countries.This contribution addresses environmental issues related to the utilization of rock phosphate as well as alternative production methods for cleaner and safer phosphate fertilizers while presenting a roadmap with measures for mitigation. 展开更多
关键词 Phosphorus fertilizer Heavy metals U-Cd-Cr-Tl SOIL Mitigation Sustainable measures EUROPE Sustainable Development Goals(SDG 3) Environmental geological survey engineering
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Exploration of Diversified Talent Training and Collaborative Innovation Models from the Perspective of Scientific Research Team Construction and Collaborative Management Mechanism in Applied Undergraduate Universities
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作者 Yuanmin Gao Hejian Liu +1 位作者 Yonggang Wang Luyao Dong 《Journal of Contemporary Educational Research》 2024年第12期1-8,共8页
This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collabo... This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collaborative innovation models.By forming an interdisciplinary scientific research team and recording in detail the team’s performance,problems encountered,and solutions during the collaborative innovation process,the study found that interdisciplinary team construction significantly improved scientific research timeliness,which was 29.33%higher than that of traditional single-disciplinary teams.Therefore,the construction of interdisciplinary scientific research teams and collaborative management mechanisms are effective ways for applied undergraduate universities to promote diversified talent training and collaborative innovation. 展开更多
关键词 Applied undergraduate Scientific research team construction Collaborative management mechanism Diversified talent training Educational model exploration
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Semi-analytical finite element method applied for characterizing micropolar fibrous composites
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作者 J.A.OTERO Y.ESPINOSA-ALMEYDA +1 位作者 R.RODRIGUEZ-RAMOS J.MERODIO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第12期2147-2164,共18页
A semi-analytical finite element method(SAFEM),based on the two-scale asymptotic homogenization method(AHM)and the finite element method(FEM),is implemented to obtain the effective properties of two-phase fiber-reinfo... A semi-analytical finite element method(SAFEM),based on the two-scale asymptotic homogenization method(AHM)and the finite element method(FEM),is implemented to obtain the effective properties of two-phase fiber-reinforced composites(FRCs).The fibers are periodically distributed and unidirectionally aligned in a homogeneous matrix.This framework addresses the static linear elastic micropolar problem through partial differential equations,subject to boundary conditions and perfect interface contact conditions.The mathematical formulation of the local problems and the effective coefficients are presented by the AHM.The local problems obtained from the AHM are solved by the FEM,which is denoted as the SAFEM.The numerical results are provided,and the accuracy of the solutions is analyzed,indicating that the formulas and results obtained with the SAFEM may serve as the reference points for validating the outcomes of experimental and numerical computations. 展开更多
关键词 semi-analytical approach fiber-reinforced composite(FRC) effective property finite element method(FEM) asymptotic homogenization method(AHM) micropolar elasticity
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Sine Cosine Optimization with Deep Learning-Based Applied Linguistics for Sentiment Analysis on COVID-19 Tweets 被引量:1
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作者 Abdelwahed Motwakel Hala J.Alshahrani +5 位作者 Abdulkhaleq Q.A.Hassan Khaled Tarmissi Amal S.Mehanna Ishfaq Yaseen Amgad Atta Abdelmageed Mohammad Mahzari 《Computers, Materials & Continua》 SCIE EI 2023年第6期4767-4783,共17页
Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19)... Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19),has severely affected the everyday life of people all over the world.Specifically,since there is insufficient access to vaccines and no straight or reliable treatment for coronavirus infection,the country has initiated the appropriate preventive measures(like lockdown,physical separation,and masking)for combating this extremely transmittable disease.So,individuals spent more time on online social media platforms(i.e.,Twitter,Facebook,Instagram,LinkedIn,and Reddit)and expressed their thoughts and feelings about coronavirus infection.Twitter has become one of the popular social media platforms and allows anyone to post tweets.This study proposes a sine cosine optimization with bidirectional gated recurrent unit-based senti-ment analysis(SCOBGRU-SA)on COVID-19 tweets.The SCOBGRU-SA technique aimed to detect and classify the various sentiments in Twitter data during the COVID-19 pandemic.The SCOBGRU-SA technique follows data pre-processing and the Fast-Text word embedding process to accomplish this.Moreover,the BGRU model is utilized to recognise and classify sen-timents present in the tweets.Furthermore,the SCO algorithm is exploited for tuning the BGRU method’s hyperparameter,which helps attain improved classification performance.The experimental validation of the SCOBGRU-SA technique takes place using a benchmark dataset,and the results signify its promising performance compared to other DL models. 展开更多
关键词 Applied linguistics deep learning sentiment analysis COVID-19 pandemic sine cosine optimization TWITTER
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Improved Attentive Recurrent Network for Applied Linguistics-Based Offensive Speech Detection
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作者 Manar Ahmed Hamza Hala J.Alshahrani +5 位作者 Khaled Tarmissi Ayman Yafoz Amira Sayed A.Aziz Mohammad Mahzari Abu Sarwar Zamani Ishfaq Yaseen 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期1691-1707,共17页
Applied linguistics is one of the fields in the linguistics domain and deals with the practical applications of the language studies such as speech processing,language teaching,translation and speech therapy.The ever-... Applied linguistics is one of the fields in the linguistics domain and deals with the practical applications of the language studies such as speech processing,language teaching,translation and speech therapy.The ever-growing Online Social Networks(OSNs)experience a vital issue to confront,i.e.,hate speech.Amongst the OSN-oriented security problems,the usage of offensive language is the most important threat that is prevalently found across the Internet.Based on the group targeted,the offensive language varies in terms of adult content,hate speech,racism,cyberbullying,abuse,trolling and profanity.Amongst these,hate speech is the most intimidating form of using offensive language in which the targeted groups or individuals are intimidated with the intent of creating harm,social chaos or violence.Machine Learning(ML)techniques have recently been applied to recognize hate speech-related content.The current research article introduces a Grasshopper Optimization with an Attentive Recurrent Network for Offensive Speech Detection(GOARN-OSD)model for social media.The GOARNOSD technique integrates the concepts of DL and metaheuristic algorithms for detecting hate speech.In the presented GOARN-OSD technique,the primary stage involves the data pre-processing and word embedding processes.Then,this study utilizes the Attentive Recurrent Network(ARN)model for hate speech recognition and classification.At last,the Grasshopper Optimization Algorithm(GOA)is exploited as a hyperparameter optimizer to boost the performance of the hate speech recognition process.To depict the promising performance of the proposed GOARN-OSD method,a widespread experimental analysis was conducted.The comparison study outcomes demonstrate the superior performance of the proposed GOARN-OSD model over other state-of-the-art approaches. 展开更多
关键词 Applied linguistics hate speech offensive language natural language processing deep learning grasshopper optimization algorithm
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Applied Linguistics with Mixed Leader Optimizer Based English Text Summarization Model
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作者 Hala J.Alshahrani Khaled Tarmissi +5 位作者 Ayman Yafoz Abdullah Mohamed Manar Ahmed Hamza Ishfaq Yaseen Abu Sarwar Zamani Mohammad Mahzari 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3203-3219,共17页
The term‘executed linguistics’corresponds to an interdisciplinary domain in which the solutions are identified and provided for real-time language-related problems.The exponential generation of text data on the Inte... The term‘executed linguistics’corresponds to an interdisciplinary domain in which the solutions are identified and provided for real-time language-related problems.The exponential generation of text data on the Internet must be leveraged to gain knowledgeable insights.The extraction of meaningful insights from text data is crucial since it can provide value-added solutions for business organizations and end-users.The Automatic Text Summarization(ATS)process reduces the primary size of the text without losing any basic components of the data.The current study introduces an Applied Linguistics-based English Text Summarization using a Mixed Leader-Based Optimizer with Deep Learning(ALTS-MLODL)model.The presented ALTS-MLODL technique aims to summarize the text documents in the English language.To accomplish this objective,the proposed ALTS-MLODL technique pre-processes the input documents and primarily extracts a set of features.Next,the MLO algorithm is used for the effectual selection of the extracted features.For the text summarization process,the Cascaded Recurrent Neural Network(CRNN)model is exploited whereas the Whale Optimization Algorithm(WOA)is used as a hyperparameter optimizer.The exploitation of the MLO-based feature selection and the WOA-based hyper-parameter tuning enhanced the summarization results.To validate the perfor-mance of the ALTS-MLODL technique,numerous simulation analyses were conducted.The experimental results signify the superiority of the proposed ALTS-MLODL technique over other approaches. 展开更多
关键词 Text summarization deep learning hyperparameter tuning applied linguistics multi-leader optimizer
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Radiation synthesis and characteristics of PTFE-g-PSSA ion exchange membrane applied in vanadium redox battery 被引量:4
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作者 PENG Jinfen QIU Jinyi NI Jiangfeng ZHAI Maolin XU Peng PENG Jing ZHOU Henghui LI Jiuqiang WEI Genshuan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第1期50-54,共5页
Radiation-induced grafting of styrene onto polytetrafluoroethylene (PTFE) membranes was studied by a simultaneous irradiation technique.Grafting was carded out usingγ-radiation from a ^(60)Co source at room temperatu... Radiation-induced grafting of styrene onto polytetrafluoroethylene (PTFE) membranes was studied by a simultaneous irradiation technique.Grafting was carded out usingγ-radiation from a ^(60)Co source at room temperature. Effects of absorbed dose,atmosphere,dose rate,and the concentration of initial monomer on the degree of grafting (DOG) were investigated and the most appropriate grafting condition was obtained.Subsequently,sulphonation of the grafted PTFE membrane (PTFE-g-PS) was carried out and a series of ion exchange membranes (PTFE-g-PSSA) was prepared.Further characterizations of FTIR,TGA,and SEM testified that grafting and sulphonation of the membranes were successfully processed;moreover,grafting of styrene not only occurred in the surface of PTFE membrane,but also in the micropores of the membrane.Ion exchange capacity (IEC) and conductivity were found increase with the grafting yield.The results suggest that at a low dose,such as 17 kGy,the ion exchange membrane (IEM) which will be suitable for vanadium redox battery (VRB) use can be obtained. 展开更多
关键词 PTFE-g-PSSA离子交换膜 辐射合成 性质 钒氧化还原电池
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Pollutant and Soil Types Influence Effectiveness of Soil-Applied Absorbents in Reducing Rice Plant Uptake of Persistent Organic Pollutants 被引量:8
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作者 LIU Cuiying JIANG Xin +1 位作者 MA Yuchun Barbara J.CADE-MENUN 《Pedosphere》 SCIE CAS CSCD 2017年第3期537-547,共11页
Persistent organic pollutants (POPs) in soils are an environmental concern due to their long-term bioavailability, which could be reduced by adding adsorbents. However, testing of these adsorbents is necessary prior... Persistent organic pollutants (POPs) in soils are an environmental concern due to their long-term bioavailability, which could be reduced by adding adsorbents. However, testing of these adsorbents is necessary prior to widespread field application. The effects of three adsorbents, nano-organic montmorillonite, nano-organic silicon dioxide (SiOs), and activated carbon, on hexachlorobenzene (HCB) and pentachlorobenzene (PeCB) accumulation in rice (Oryza sativa L.) plants were tested in a greenhouse experiment using two soils, a Hydragric Acrisol (Ac) and a Gleyi-Stagnic Anthrosol (An). The bioconcentration factors (BCFs) of HCB and PeCB to rice roots were 2.3-3.7 and 2.0 3.0 times those to rice shoots, respectively. The applications of the three adsorbents decreased HCB and PeCB extractability in Ac, while only the application of activated carbon decreased their extractability in An. The bioavailability of HCB and PeCB to rice plants in Ac was higher than that in An. In Ac, the applications of nano-organic SiOs and activated carbon decreased the BCF of HCB to rice roots by 16.1% and 26.8%, respectively, whereas only the application of activated carbon decreased the BCF of PeCB to rice roots by 31.4%, compared to the control. In An, only the application of activated carbon decreased the BCFs of HCB and PeCB to rice roots by 22.9% and 18.2%, respectively, compared to the control. However, the application of nano-organic montmorillonite inhibited rice growth in both soils. The results of this study suggested that the effectiveness of adsorbents would vary with pollutant and soil types, providing a reference point for developing efficient adsorbents to reduce the ecological risk of POPs. 展开更多
关键词 accumulation activated carbon bioconcentration factor HEXACHLOROBENZENE NANO-MATERIALS pentachlorobenzene
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Large eddy simulation of unsteady flow in gas-liquid separator applied in thorium molten salt reactor 被引量:2
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作者 Jing-Jing Li Ya-Lan Qian +3 位作者 Jun-Lian Yin Hua Li Wei Liu De-Zhong Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第5期10-18,共9页
Axial gas-liquid separators have been adopted in fission gas removal systems for the development of thorium molten salt reactors. In our previous study, we observed an unsteady flow phenomenon in which the flow patter... Axial gas-liquid separators have been adopted in fission gas removal systems for the development of thorium molten salt reactors. In our previous study, we observed an unsteady flow phenomenon in which the flow pattern is directly dependent on the backpressure in a gas-liquid separator; however, the underlying flow mechanism is still unknown. In order to move a step further in clarifying how the flow pattern evolves with a variation in backpressure, a large eddy simulation(LES) was adopted to study the flow field evolution. In the simulation, an artificial boundary was applied at the separator outlet under the assumption that the backpressure increases linearly. The numerical results indicate that the unsteady flow feature is captured by the LES approach, and the flow transition is mainly due to the axial velocity profile redistribution induced by the backpressure variation. With the increase in backpressure,the axial velocity near the downstream orifice transits from negative to positive. This change in the axial velocity sign forces the unstable spiral vortex to become a stable rectilinear vortex. 展开更多
关键词 SWIRL flow THORIUM MOLTEN SALT reactor Computational fluid dynamics Large EDDY simulation
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Hyperbranched Polyurethane Acrylate Applied to UV Curable Flame Retardant Coatings 被引量:2
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作者 ZHU Sheng-Wu SHI Wen-Fang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第3期331-333,共3页
UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyester... UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyesters for UV curing coatings by Hult and his colleagues has been reported. However, the UV cured films from those materials are all flammable when attached to fire without addition of flame retardants. 展开更多
关键词 Flame retardant Polyurethane acrylate PHOSPHORUS UV curing
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Temporal patterns of three sympatric pheasant species in the Nanling Mountains: N-mixture modeling applied to detect abundance 被引量:4
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作者 Fasheng Zou Qiang Zhang +4 位作者 Min Zhang Myung‑Bok Lee Xincai Wang Yuening Gong Changteng Yang 《Avian Research》 CSCD 2019年第4期405-414,共10页
Background:The reliability of long-term population estimates is crucial for conservation and management purposes.Most previous studies assume that count indices are proportionally related to abundance;however,this ass... Background:The reliability of long-term population estimates is crucial for conservation and management purposes.Most previous studies assume that count indices are proportionally related to abundance;however,this assumption may not hold when detection varies spatially and temporally.We examined seasonal variations in abundance of three bird species(Cabot’s Tragopan Tragopan caboti,Silver Pheasant Lophura nycthemera,and Whitenecklaced Partridge Arborophila gingica) along an elevational gradient,using N-mixture models that take into account imperfect detection in our bird data.Methods:Camera-trapping was used to monitor temporal activity patterns of these species at Guangdong Nanling National Nature Reserve from December 2013 to November 2017(4 seasons per year).For abundance analysis(N-mixture modeling),we divided a year into 4 seasons,i.e.3 months per season,and performed the analysis by season.Elevation was incorporated into the N-mixture model as a covariate that may affect abundance.We compared the N-mixture model with a null model(no covariate model) and selected the better model based on AIC values to make an inference.Results:From 24 sampling sites,we obtained 6786 photographs of 8482 individuals of 44 bird species and 26 mammal species.Silver Pheasant was photographed much more frequently and showed higher temporal activity frequency than White-necklaced Partridge or Cabot’s Tragopan.Silver Pheasant was camera-captured most frequently in summer,and other two species in winters.All three species had two daytime activity peaks:between 6:00 a.m.and 10:00 a.m.,and between 5:00 p.m.and 7:00 p.m.,respectively.Our estimated abundance and detection probability from the N-mixture model were variable by season.In particular,all three species showed greater abundance in summer than in winter,and estimated abundance patterns of all three species were more similar with observed cameratrapping counts in summers.Moreover,in winter,elevation had a positive impact on abundance of Silver Pheasant and Cabot’s Tragopan,but not on White-necklaced Partridge.Conclusions:Our results demonstrate that the N-mixture model performed well in the estimation of temporal popu lation abundance at local fixed permanent plots in mountain habitat in southern China,based on the modeling of repeated camera-trapping counts.The seasonal differences in abundance of the three endemic bird species and the strong effect of elevation on abundance of two species in winter were only indicative of variations in spatio-tempora distribution within species and between species.In identifying suitable habitat for endemic pheasants,the positive elevational effect also suggests that more attention should be paid to conservation of areas with higher elevation in the Nanling Mountains. 展开更多
关键词 Abundance estimation CAMERA-TRAPPING Imperfect detectability Nanling Mountains Spatio-temporal distribution Sympatric distribution
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Development and assessment of a multifunctional chitosan-based coating applied on AZ31 magnesium alloy: Corrosion resistance and antibacterial performance against Klebsiella Pneumoniae 被引量:2
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作者 Emmanuel Mena-Morcillo Lucien Veleva +3 位作者 Mariana Cerda-Zorrilla Montserrat Soria-Castro Juan C.Castro-Alcátara Rosa C.Canul-Puc 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第6期2133-2144,共12页
This work presents a simple method to functionalise the surface of AZ31 magnesium alloy by applying a duplex MgF_(2)/chitosan coating,which improves its corrosion resistance and provides it with some antibacterial per... This work presents a simple method to functionalise the surface of AZ31 magnesium alloy by applying a duplex MgF_(2)/chitosan coating,which improves its corrosion resistance and provides it with some antibacterial performance.First,the effect of three chitosan solutions with different concentrations on the growth of the bacteria Klebsiella pneumoniae in nutritive medium(TSB)was evaluated by absorbance kinetics experiments,where the chitosan solution at 2%(m/V)was selected for the coating preparation.Before coating application,the AZ31 substrate was pretreated with hydrofluoric acid for 48 hours in order to form a MgF_(2)conversion layer.Subsequently,the coating was applied to the pretreated substrate through the dry-casting method.Samples of the alloy in each surface condition(bare,pretreated,and pretreated+coated with chitosan)were exposed to simulated body fluid(SBF)for 21 days at 37°C,with the solution renewed every 24 hours and the wastes stored.The surfaces were characterised by SEM-EDS,and XPS after the immersion tests,whereas the stored solutions were employed to measure the change in the Mg-ions concentration.Electrochemical impedance spectroscopy and potentiodynamic polarisation were performed in each surface condition to compare their corrosion resistance in SBF.The antibacterial activity of the functionalised surfaces was evaluated by the plate counting method and compared with bare samples.All results were correlated and demonstrate that the modified surface of AZ31 achieved a higher corrosion resistance when it was exposed to SBF,as well as a reduction of the bacterial growth during in vitro tests. 展开更多
关键词 AZ31 Chitosan coating Simulated body fluid Corrosion Antibacterial activity
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ENRICHED GOAL-ORIENTED ERROR ESTIMATION APPLIED TO FRACTURE MECHANICS PROBLEMS SOLVED BY XFEM 被引量:1
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作者 Zhijia Lin Zhuo Zhuang +2 位作者 Xiaochuan You Heng Wang Dandan Xu 《Acta Mechanica Solida Sinica》 SCIE EI 2012年第4期393-403,共11页
Based on the concept of constitutive relation error along with the residual of both origin and dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed in this paper. It lea... Based on the concept of constitutive relation error along with the residual of both origin and dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed in this paper. It leads to high quality local error bounds in the problem of fracture mechanics simulation with extended finite element method (XFEM), which involves enrichment to solve a stress singularity in the crack. Since goal-oriented error estimation with enriched degrees of freedom gives us a chance to evaluate the XFEM simulation, the stress intensity factor calculated by two kinds of XFEM programs developed by ourselves and by commercial code ABAQUS are compared in this work. By comparing the reliability of the stress intensity factor calculation, the accuracy of two programs in different cases is evaluated and the source of error is discussed. A 2-dimensional XFEM example is given to illustrate the computational procedure. 展开更多
关键词 goal-oriented error estimation extended finite element method fracture mechanics error bounds
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PSE as applied to problems of transition in compressible boundary layers 被引量:1
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作者 张永明 周恒 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第7期833-840,共8页
A new idea of using the parabolized stability equation (PSE) method to predict laminar-turbulent transition is proposed. It is tested in the prediction of the location of transition for compressible boundary layers ... A new idea of using the parabolized stability equation (PSE) method to predict laminar-turbulent transition is proposed. It is tested in the prediction of the location of transition for compressible boundary layers on fiat plates, and the results are compared with those obtained by direct numerical simulations (DNS). The agreement is satisfactory, and the reason for this is that the PSE method faithfully reproduces the mechanism leading to the breakdown process in laminar-turbulent transition, i.e., the modification of mean flow profile leads to a remarkable change in its stability characteristics. 展开更多
关键词 parabolized stability equations direct numerical simulations transition breakdown
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Hybridization of Fuzzy and Hard Semi-Supervised Clustering Algorithms Tuned with Ant Lion Optimizer Applied to Higgs Boson Search 被引量:1
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作者 Soukaina Mjahed Khadija Bouzaachane +2 位作者 Ahmad Taher Azar Salah El Hadaj Said Raghay 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第11期459-494,共36页
This paper focuses on the unsupervised detection of the Higgs boson particle using the most informative features and variables which characterize the“Higgs machine learning challenge 2014”data set.This unsupervised ... This paper focuses on the unsupervised detection of the Higgs boson particle using the most informative features and variables which characterize the“Higgs machine learning challenge 2014”data set.This unsupervised detection goes in this paper analysis through 4 steps:(1)selection of the most informative features from the considered data;(2)definition of the number of clusters based on the elbow criterion.The experimental results showed that the optimal number of clusters that group the considered data in an unsupervised manner corresponds to 2 clusters;(3)proposition of a new approach for hybridization of both hard and fuzzy clustering tuned with Ant Lion Optimization(ALO);(4)comparison with some existing metaheuristic optimizations such as Genetic Algorithm(GA)and Particle Swarm Optimization(PSO).By employing a multi-angle analysis based on the cluster validation indices,the confusion matrix,the efficiencies and purities rates,the average cost variation,the computational time and the Sammon mapping visualization,the results highlight the effectiveness of the improved Gustafson-Kessel algorithm optimized withALO(ALOGK)to validate the proposed approach.Even if the paper gives a complete clustering analysis,its novel contribution concerns only the Steps(1)and(3)considered above.The first contribution lies in the method used for Step(1)to select the most informative features and variables.We used the t-Statistic technique to rank them.Afterwards,a feature mapping is applied using Self-Organizing Map(SOM)to identify the level of correlation between them.Then,Particle Swarm Optimization(PSO),a metaheuristic optimization technique,is used to reduce the data set dimension.The second contribution of thiswork concern the third step,where each one of the clustering algorithms as K-means(KM),Global K-means(GlobalKM),Partitioning AroundMedoids(PAM),Fuzzy C-means(FCM),Gustafson-Kessel(GK)and Gath-Geva(GG)is optimized and tuned with ALO. 展开更多
关键词 Ant lion optimization binary clustering clustering algorithms Higgs boson feature extraction dimensionality reduction elbow criterion genetic algorithm particle swarm optimization
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Diffusion Coefficient in Silicon Solar Cell with Applied Magnetic Field and under Frequency: Electric Equivalent Circuits 被引量:3
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作者 Amadou Diao Ndeye Thiam +3 位作者 Martial Zoungrana Gokhan Sahin Mor Ndiaye Grégoire Sissoko 《World Journal of Condensed Matter Physics》 2014年第2期84-92,共9页
In this paper, a theory on the determination of the diffusion coefficient of excess minority carriers in the base of a silicon solar cell is presented. The diffusion coefficient expression has been established and is ... In this paper, a theory on the determination of the diffusion coefficient of excess minority carriers in the base of a silicon solar cell is presented. The diffusion coefficient expression has been established and is related to both frequency modulation and applied magnetic field;the study is then carried out using the impedance spectroscopy method and Bode diagrams. From the diffusion coefficient, we deduced the diffusion length and the minority carriers’ mobility. Electric parameters were derived from the diffusion coefficient equivalent circuits. 展开更多
关键词 SOLAR Cell Magnetic Field FREQUENCY MODULATION DIFFUSION COEFFICIENT
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PV-Wind-Diesel System for Energy Supply on Remote Area Applied for Telecommunication Towers in Comoros 被引量:1
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作者 Fahad Maoulida Djedjig Rabah +1 位作者 Mohammed El Ganaoui Kassim Mohamed Aboudou 《Open Journal of Energy Efficiency》 2021年第2期50-72,共23页
The Comoros is an archipelago in the Indian Ocean located in the Mozambique Channel between the African continent and Madagascar. Geographically Comoros is composed of four islands: Grande Comores, Anjouan, Mohél... The Comoros is an archipelago in the Indian Ocean located in the Mozambique Channel between the African continent and Madagascar. Geographically Comoros is composed of four islands: Grande Comores, Anjouan, Mohéli and Mayotte (under French administration). Apart from Mayotte, the others three independent islands commonly known as the Union of the Comoros are suffering from energy stress since their independence year 1975 until nowadays. The energy supplied and distributed by the national electricity company, SONELEC produced by diesel engines, is not stable with so much load shedding all the time. This instability energy leads to a lack of a phone network in some telecommunications towers connected to grid. The majority of telecommunications towers are located in rural areas not connected to grid and running on diesel generators, which once again leads to a problem with the telecommunications network when diesel engines fail. The two competing companies which operate in the field of telecommunications in the Comoros, namely Comores Télécom, a national public company and Telma, the private one, are still unable to ensure the provision of the telecommunications network on a regular basis. This is why we propose in the present work, a sizing of hybrid system composed essentially of a diesel generator, a wind turbine and a photovoltaic solar system with storage in batteries for supplying telecommunications towers in order to permanently ensure the provision of the telecommunications network for the well-being of the population. Our future energy must be based on non-polluting energies with significant resources. Renewable energies are the best candidates but with intermittent production especially in rural areas not connected to the national electricity grid whose energy demand is more important to meet the needs of the population. The aim of this work is the sizing of a hybrid system composed of a diesel generator, a wind turbine and a photovoltaic solar system with storage in batteries for supplying telecommunications towers located in rural areas in the Comoros. In fact, to verify the performance of the hybrid system, a numerical study has been carried out with the HOMER 2.68 Beta software using meteorological data from the Comoros. The results obtained show that this hybrid combination is more profitable in the margin of economic cost and environmental assessments with a less expensive investment. These results also show a better optimization of Wind/PV/Battery of the hybrid system used, satisfying the demand and contributing to the preservation of the environment to fight against climate change with a low cost of energy. 展开更多
关键词 Hybrid System Renewable Energy HOMER Meteorological Data TELECOMMUNICATION TOWERS Rural Area
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Analytic equation of state for solids with multi-exponential potential based on analytic mean field potential approach and applied to the epsilon phase of solid oxygen
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作者 王立国 孙久勋 杨维 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2867-2873,共7页
The thermodynamic properties of the ε phase of solid oxygen are studied by using the analytic mean field approach (AMFP). Analytic expressions for the Helmholtz free energy, internal energy and equation of state of... The thermodynamic properties of the ε phase of solid oxygen are studied by using the analytic mean field approach (AMFP). Analytic expressions for the Helmholtz free energy, internal energy and equation of state of solid oxygen have been derived based on the multi-exponential potential. The formulism for the case of double-exponential (DE) model is applied to the ε phase of solid oxygen. Its four potential parameters are determined through fitting the experimental compression data of the ε phase of solid oxygen. Numerical results of the pressure dependence of the volume calculated by using the AMFP are in good agreement with the original experimental data. This suggests that the AMFP is a useful approach to study the thermodynamic properties of the ε phase of solid oxygen. Furthermore, we predict the variation of the volume, lattice parameters and intermolecular distances with pressure, and some thermodynamic quantities versus volume, at several higher temperatures. 展开更多
关键词 analytic equation of state analytic mean field approach solid oxygen ε phase
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Performance Comparison of Two Efficient Genomic Selection Methods(gsbay & MixP ) Applied in Aquacultural Organisms
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作者 SU Hailin LI Hengde +2 位作者 WANG Shi WANG Yangfan BAO Zhenmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期137-144,共8页
Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to br... Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to bring the advantages of genomic selection to scallop breeding. Two different genomic selection tools Mix P and gsbay were applied on genomic evaluation of simulated data and Zhikong scallop(Chlamys farreri) field data. The data were compared with genomic best linear unbiased prediction(GBLUP) method which has been applied widely. Our results showed that both Mix P and gsbay could accurately estimate single-nucleotide polymorphism(SNP) marker effects, and thereby could be applied for the analysis of genomic estimated breeding values(GEBV). In simulated data from different scenarios, the accuracy of GEBV acquired was ranged from 0.20 to 0.78 by Mix P; it was ranged from 0.21 to 0.67 by gsbay; and it was ranged from 0.21 to 0.61 by GBLUP. Estimations made by Mix P and gsbay were expected to be more reliable than those estimated by GBLUP. Predictions made by gsbay were more robust, while with Mix P the computation is much faster, especially in dealing with large-scale data. These results suggested that both algorithms implemented by Mix P and gsbay are feasible to carry out genomic selection in scallop breeding, and more genotype data will be necessary to produce genomic estimated breeding values with a higher accuracy for the industry. 展开更多
关键词 GENOMIC SELECTION SCALLOP BREEDING method comparison
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Goal-oriented error estimation applied to direct solution of steady-state analysis with frequency-domain finite element method
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作者 林治家 由小川 庄茁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期539-552,共14页
Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed. It lead... Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed. It leads to the high quality locM error bounds in the problem of the direct-solution steady-state dynamic analysis with a frequency-domain finite element, which involves the enrichments with plural variable basis functions. The solution of the steady-state dynamic procedure calculates the harmonic response directly in terms of the physical degrees of freedom in the model, which uses the mass, damping, and stiffness matrices of the system. A three-dimensional finite element example is carried out to illustrate the computational procedures. 展开更多
关键词 goal-oriented error estimation finite element method (FEM) direct-solutionsteady-state analysis frequency domain
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