The rapid growth of streaming media applications on the Internet is proposing higher requirements on energy consumption and I/O performance of the storage systems.However,the optimized I/O requests from different init...The rapid growth of streaming media applications on the Internet is proposing higher requirements on energy consumption and I/O performance of the storage systems.However,the optimized I/O requests from different initiators will be mixed disorderly when they are reaching the storage system concurrently,which leads to increasing energy consumption.This paper proposes an energy-saving scheduling scheme based on I/O Stream(ES-IOS).The ES-IOS scheme can take the advantage of the I/O characteristics of streaming media and reorganize the mixed and disordered I/O requests into "streams".Technically,The ES-IOS scheme includes two main points,a priority-based weighted stream scheduling algorithm(PWSS) and a regression-fitting-based popularity prediction algorithm(RFPP).The PWSS algorithm can schedule the I/O streams in weighted queue based on priority to limit energy consumption.The priority of each stream is determined by its popularity.According to the I/O access records over a period,the RFPP algorithm can predict the popularity of each stream via regression fitting.Based on the popularities,the PWSS algorithm assigns more continuous service time to the hot streams and reversely less service time to the cold ones.Trace-driven experiments show that the ES-IOS scheme can reduce the energy consumption by 38%and enhance the I/O throughput by 27%approximately.展开更多
Project-based learning has been in widespread use in education. However, project managers are unaware of the students’ lack of experience and treat them as if they were professional staff. This paper proposes the app...Project-based learning has been in widespread use in education. However, project managers are unaware of the students’ lack of experience and treat them as if they were professional staff. This paper proposes the application of a fuzzy failure mode and effects analysis model for project-based software engineering education. This method integrates the fuzzy rule-based system with learning agents. The agents construct the membership function from historical data. Data are processed by a clustering process that facilitates the construction of the membership function. It helps students who lack experience in risk assessment to develop their expertise in that skill. The paper also suggests a classification technique for a fuzzy rule-based system that can be used to judge risk based on a fuzzy inference system. The student project will thus be further enhanced with respect to risk assessment. We then discuss the design of experiments to verify the proposed model.展开更多
Background Autism spectrum disorder(ASD)is a pervasive developmental disorder characterized by difficulties in social communication and restricted,repetitive behaviors.Early intervention is essential to improve develo...Background Autism spectrum disorder(ASD)is a pervasive developmental disorder characterized by difficulties in social communication and restricted,repetitive behaviors.Early intervention is essential to improve developmental outcomes in children with ASD.Serious games,which combine educational objectives with game based interactions,have shown potential as tools for early intervention in patients with ASD.However,in China,the development of serious games specifically designed for children with ASD remains in its infancy,with significant gaps in technical frameworks and effective data management methods.Method This paper proposes a framework aimed at facilitating the development of multimodal serious games designed for ASD interventions.We demonstrated the feasibility of the framework by developing and integrating several components,such as web applications,mobile games,and augmented reality games.These tools are interconnected to achieve data connectivity and management.Additionally,adaptive mechanics were employed within the framework to analyze real-time player data,which allowed the game difficulty to be dynamically adjusted and provide a personalized experience for each child.Results The framework successfully integrated various multimodal games,ensuring that real-time data management supported personalized game experiences.This approach ensured that the interventions remained appropriately challenging while still achievable.Conclusion The results indicate that the proposed framework enhances collaboration among therapists,parents,and developers while also improving the effectiveness of ASD interventions.By delivering personalized gameplay experiences that are both challenging and achievable,the framework offers a scalable platform for the future development of serious games.展开更多
Social media has emerged as one of the most transformative developments on the internet,revolu-tionizing the way people communicate and interact.However,alongside its benefits,social media has also given rise to signi...Social media has emerged as one of the most transformative developments on the internet,revolu-tionizing the way people communicate and interact.However,alongside its benefits,social media has also given rise to significant challenges,one of the most pressing being cyberbullying.This issue has become a major concern in modern society,particularly due to its profound negative impacts on the mental health and well-being of its victims.In the Arab world,where social media usage is exceptionblly high,cyberbullying has become increasingly prevalent,necessitating urgent attention.Early detection of harmful online behavior is critical to fostering safer digital environments and mitigating the adverse efcts of cyberbullying.This underscores the importance of developing advanced tools and systems to identify and address such behavior efectively.This paper investigates the development of a robust cyberbullying detection and classifcation system tailored for Arabic comments on YouTube.The study explores the efectiveness of various deep learning models,including Bi-LSTM(Bidirectional Long Short Term Memory),LSTM(Long Short-Term Memory),CNN(Convolutional Neural Networks),and a hybrid CNN-LSTM,in classifying Arabic comments into binary classes(bullying or not)and multiclass categories.A comprehensive dataset of 20,000 Arabic YouTube comments was collected,preprocessed,and labeled to support these tasks.The results revealed that the CNN and hybrid CNN-LSTM models achieved the highest accuracy in binary classification,reaching an impressive 91.9%.For multiclass dlassification,the LSTM and Bi-LSTM models outperformed others,achieving an accuracy of 89.5%.These findings highlight the efctiveness of deep learning approaches in the mitigation of cyberbullying within Arabic online communities.展开更多
为了改善软件的质量和生产性,注目于与其密切相关的软件结构.首先,讨论了现有方法中软件结构分析和设计的问题;然后根据质量设计中的质量屋HOQ(house of quality)与产品设计中的工程图之间的相似性,将质量功能展开QFD(quality function ...为了改善软件的质量和生产性,注目于与其密切相关的软件结构.首先,讨论了现有方法中软件结构分析和设计的问题;然后根据质量设计中的质量屋HOQ(house of quality)与产品设计中的工程图之间的相似性,将质量功能展开QFD(quality function deployment)中的质量屋HOQ概念扩展成一种软件描述工具,并引入H.A.西蒙的系统准分解可能性原理,提出了基于数量化理论3类QMT3(quantification method of type 3)的软件定量结构化方法,再通过与现有方法的比较分析,阐明了该方法的特点;最后,通过应用实例验证了该方法对软件结构分析和设计的有效性.因而为软件质量保证提供了有力的支持.展开更多
Multi-faults detection is a challenge for rolling bearings due to the mode mixture and coupling of multiple fault features,as well as its easy burying in the complex,non-stationary structural vibrations and strong bac...Multi-faults detection is a challenge for rolling bearings due to the mode mixture and coupling of multiple fault features,as well as its easy burying in the complex,non-stationary structural vibrations and strong background noises.In this paper,a method based on the flexible analytical wavelet transform(FAWT)possessing fractional scaling and translation factors is proposed to identify multiple faults occurred in different components of rolling bearings.During the route of the proposed method,the proper FAWT bases are constructed via genetic optimization algorithm(GA)based on maximizing the spectral correlated kurtosis(SCK)which is firstly presented and proved to be efficient and effective in indicating interested fault mode.Via using the customized FAWT bases for each interested fault mode,the original vibration measurements are decomposed into fine frequency subbands,and the sensitive subband which enhances the signal-to-noise ratio(SNR)is selected to exhibit the fault signature on its envelope spectrum.The proposed method is tested via simulated signals,and applied to analyze the experimental vibration measurements from the running roller bearings subjected to outrace,inner-race and roller defects.The analysis results validate the effectiveness of the proposed method in identifying multi-faults occurred in different components of rolling bearings.展开更多
Global environmental problems have been increasing with the growth of the world economy and have become a crucial issue.To replace fossil fuels,sustainable and eco-friendly catalysts are required for the removal of or...Global environmental problems have been increasing with the growth of the world economy and have become a crucial issue.To replace fossil fuels,sustainable and eco-friendly catalysts are required for the removal of organic pollutants.In this study,nickel ferrite(NiFe_(2)O_(4))was prepared using a simple wet-chemical synthesis,followed by calcination;bismuth phosphate(BiPO_(4))was also prepared using a hydrothermal method.Further,NiFe_(2)O_(4)/BiPO_(4)nanocomposites were prepared using a hydrothermal technique.Numerous characterization studies,such as structural,morphology,surface area,optical,photoluminescence,and photoelectrochemical investigations,were used to analyze NiFe_(2)O_(4)/BiPO_(4)nanocomposites.The morphology analysis indicated a successful decoration of BiPO_(4)nanorods on the surface of Ni Fe_(2)O_(4)nanoplate.Further,the bandgap of the NiFe_(2)O_(4)/BiPO_(4)nanocomposites was modified owing to the formation of a heterostructure.The as-prepared NiFe_(2)O_(4)/BiPO_(4)nanocomposite exhibited promising properties to be used as a novel heterostructure for tetracycline(TC)and Rhodamine B(Rh B)removal.The NiFe_(2)O_(4)/BiPO_(4)nanocomposite degrades TC(98%)and Rh B(99%)pollutants upon solar-light irradiation within 100 and 60 min,respectively.Moreover,the trapping experiments confirmed the Z-scheme approach of the prepared nanocomposites.The efficient separation and transfer of photogenerated electron-hole pairs rendered by the heterostructure were confirmed by utilizing electrochemical impedance spectroscopy,photocurrent experiments,and photoluminescence.Mott–Schottky measurements were used determine the positions of the conduction and valence bands of the samples,and the detailed mechanism of photocatalytic degradation of toxic pollutants was projected and discussed.展开更多
In network service systems,satisfying quality of service(QoS)is one of the main objectives.Admission control and resource allocation strategy can be used to guarantee the QoS requirement.Based on partially observable ...In network service systems,satisfying quality of service(QoS)is one of the main objectives.Admission control and resource allocation strategy can be used to guarantee the QoS requirement.Based on partially observable Markov decision processes(POMDPs),this paper proposes a novel admission control model for video on demand(VOD)service systems with elastic QoS.Elastic QoS is also considered in resource allocation strategy.Policy gradient algorithm is often available to find the solution of POMDP problems,with a satisfactory convergence rate.Through numerical examples,it can be shown that the proposed admission control strategy has better performance than complete admission control strategy.展开更多
The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit...The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit competitive fluorescence detection performance of chloride ion(Cl)in aqueous solutio n.Under the optimized conditions,the concentration of Cl could be quantitative analyzed with the Ag-PCN in a wide detection range from 0.5 mmol/L to 0.1 mol/L,with a low detection limitation of 0.06 mmol/L.It is confirmed that the fluorescence of PCN could be effectively decayed by the photoinduced charge transfer via the adsorbed Cl for trapping holes,mainly by means of the time-resolved fluorescence and surface photo voltage spectra.The porous structure and modified Ag promote the adsorption of Cl on resulting Ag-PCN,leading to excellent fluorescence detection for Cl.This work provides a feasible route to develop a fluorescence detection of Cl with g-C_(3)N_(4) nanosheets in environment water.展开更多
The measurement and prediction of gas pulsations are performed along the discharge pipeline of a reciprocating compressor for a refrigerator. A regression based experimental model of the one-dimensional acoustic field...The measurement and prediction of gas pulsations are performed along the discharge pipeline of a reciprocating compressor for a refrigerator. A regression based experimental model of the one-dimensional acoustic field is developed. First, the conventional method for gas pulsation measurement and prediction, which separates the incident and reflected wave of acoustic waves traveling in the frequency domain, is discussed. Then, regression based on our proposed simple model, which is able to predict gas pulsation compared to the conventional method, is introduced for the analysis of a reciprocating compressor(The conventional method requires the value of sound speed in the piping line for the reciprocating compressor). A numerical prediction is made for the regression method. Three power spectrum values along the discharge pipeline are used for analysis, and two values are used for verification. Our results are in a good agreement with the conventional method.展开更多
With no annealing treatment, cathodic polarization trends in 5083F A1 alloy revealed concentration polarization and activation polarization. However, the annealed specimens have lower current densities at corrosion pr...With no annealing treatment, cathodic polarization trends in 5083F A1 alloy revealed concentration polarization and activation polarization. However, the annealed specimens have lower current densities at corrosion protection potential compared to the non-annealed specimen. The results of SSRTs conducted in seawater at the applied potential range of-l.8 V to -0.5 V indicated that the maximum tensile strength, elongation, and time-to-fracture had high values at applied potentials of -0.7 to -1.4 V. The maximum tensile strength, elongation, and time-to-f？acture decreased when the potential values were beyond this range in either anodic or cathodic direction. In general, the increased shear lip caused by annealing treatment indicates elongation. Time-to-fracture would likely increase with elongation. Potentials between -0.5 V to -0.6 V were found to be in the region of stress corrosion cracking. The corrosion protection zone was determined to be -0.7 V to -J,4 V because these potential ranges produced good mechanical properties. Potential less than -1.4 V produced a fractured surface with a mixture of dimples （ductile fractures） and a quasi-cleavage pattern resulting from the effects of hydrogen gas.展开更多
Steel applied in ocean environment is exposed to corrosion and cavitation and is subject to increasing damages. To prevent this, anti-corrosion thermal spray coating technique is widely used. The low-temperature therm...Steel applied in ocean environment is exposed to corrosion and cavitation and is subject to increasing damages. To prevent this, anti-corrosion thermal spray coating technique is widely used. The low-temperature thermal spray coating was performed with 85%Al-14.5%Zn-0.5%Zr for ship materials and various sealing materials were applied to improve its durability, and the electrochemical behavior and cavitation characteristics were observed. The results show that the sealing improves all the properties of the materials. Hybrid ceramic and fluoro-silicon sealing materials show good electrochemical characteristics, and the fluoro-silieon sealing material shows the best anti-cavitation characteristics.展开更多
Redox flow batteries offer a potential solution to an increase in renewable energy generation on the grid by offering long-term, large-scale storage and regulation of power. However, they are currently un- derutilised...Redox flow batteries offer a potential solution to an increase in renewable energy generation on the grid by offering long-term, large-scale storage and regulation of power. However, they are currently un- derutilised due to cost and performance issues, many of which are linked to the microstructure of the porous carbon electrodes used. Here, for the first time, we offer a detailed study of the in situ effects of compression on a commercially available carbon felt electrode. Visualisation of electrode structure us- ing X-ray computed tomography shows the non-linear way that these materials compress and various metrics are used to elucidate the changes in porosity, pore size distribution and tortuosity factor under compressions from 0%-90%.展开更多
An integrated implementation framework of an intelligent recommendation system for outdoor video advertising is proposed, which is based on the analysis of audiences＇ characteristics. Firstly, the images of the scene...An integrated implementation framework of an intelligent recommendation system for outdoor video advertising is proposed, which is based on the analysis of audiences＇ characteristics. Firstly, the images of the scene and the people who view the video advertisements are captured by the net- work camera deployed on the video advertising terminal side. Then audiences＇ characteristics can be obtained by applying computer vision technologies ： face detection, face tracking, gender recogni- tion and age estimation. Finally, an intelligent recommendation algorithm is designed to decide the most fitting video ads for each terminal according to multi-dimensional statistical information of its reover, a novel face detection method and a new face tracking method have been proposed to meet the practical requirements of the system, of which the average Fl-score is O. 988 and 0. 951 respec- tively.展开更多
The corrosions resulting from defects in painting layers frequently occur in Al alloys, so the application of corrosion preventing systems is also very important. Optimum conditions in terms of electrochemistry in rel...The corrosions resulting from defects in painting layers frequently occur in Al alloys, so the application of corrosion preventing systems is also very important. Optimum conditions in terms of electrochemistry in relation to solution treatment, quenching and artificial aging treatment were established in order to optimize precipitation strengthening conditions intended to enhance the strength of Al alloys. Slow strain rate tests （SSRT） at various applied potentials were conducted in potential range from -1.8 to 0.5 V. The results show that the maximum tensile strengths, elongations and time-to-fracture are shown to be high values. After precipitation strengthening heat treatment, a tendency appear that time-to-fracture increases as elongation increases. In the potential range from -1.3 V to -0.7 V, the specimens show excellent mechanical properties, and thus this range is considered to be a corrosion prevention range.展开更多
Medical image segmentation has consistently been a significant topic of research and a prominent goal,particularly in computer vision.Brain tumor research plays a major role in medical imaging applications by providin...Medical image segmentation has consistently been a significant topic of research and a prominent goal,particularly in computer vision.Brain tumor research plays a major role in medical imaging applications by providing a tremendous amount of anatomical and functional knowledge that enhances and allows easy diagnosis and disease therapy preparation.To prevent or minimize manual segmentation error,automated tumor segmentation,and detection became the most demanding process for radiologists and physicians as the tumor often has complex structures.Many methods for detection and segmentation presently exist,but all lack high accuracy.This paper’s key contribution focuses on evaluating machine learning techniques that are supposed to reduce the effect of frequently found issues in brain tumor research.Furthermore,attention concentrated on the challenges related to level set segmentation.The study proposed in this paper uses the Population-based Artificial Bee Colony Clustering(P-ABCC)methodology to reliably collect initial contour points,which helps minimize the number of iterations and segmentation errors of the level-set process.The proposed model measures cluster centroids(ABC populations)and uses a level-set approach to resolve contour differences as brain tumors vary as they have irregular form,structure,and volume.The suggested model comprises of three major steps:first,pre-processing to separate the brain from the head and improves contrast stretching.Secondly,P-ABCC is used to obtain tumor edges that are utilized as an initial MRI sequence contour.The level-set segmentation is then used to detect tumor regions from all volume slices with fewer iterations.Results suggest improved model efficiency compared to state-of-the-art methods for both datasets BRATS 2019 and BRATS 2017.At BRATS 2019,dice progress was achieved for Entire Tumor(WT),Tumor Center(TC),and Improved Tumor(ET)by 0.03%,0.03%,and 0.01%respectively.At BRATS 2017,an increase in precision for WT was reached by 5.27%.展开更多
Previously we have designed and implemented new image browsing facilities to support effective offiine image contents on mobile devices with limited capabilities： low bandwidth, small display, and slow processing. In...Previously we have designed and implemented new image browsing facilities to support effective offiine image contents on mobile devices with limited capabilities： low bandwidth, small display, and slow processing. In this letter, we fulfill the automatic production of cartoon contents fitting small-screen display, and introduce a clustering method useful for various types of cartoon images as a prerequisite stage for preserving semantic meaning. The usage of neural networks is to properly cut the various forms of pages. Texture information that is useful for grayscale image segmentation gives us a good clue for page layout analysis using the multilayer perceptron （MLP） based x-y recursive algorithm. We also automatically frame the segment MLP using agglomerative segmentation. Our experimental results show that the combined approaches yield good results of segmentation for several cartoons.展开更多
We consider the(2+1)-dimensional nonlinear Schrodinger equation with power-law nonlinearity under the parity-time-symmetry potential by using the Crank-Nicolson alternating direction implicit difference scheme,which c...We consider the(2+1)-dimensional nonlinear Schrodinger equation with power-law nonlinearity under the parity-time-symmetry potential by using the Crank-Nicolson alternating direction implicit difference scheme,which can also be used to solve general boundary problems under the premise of ensuring accuracy.We use linear Fourier analysis to verify the unconditional stability of the scheme.To demonstrate the effectiveness of the scheme,we compare the numerical results with the exact soliton solutions.Moreover,by using the scheme,we test the stability of the solitons under the small environmental disturbances.展开更多
To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating l...To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating layers by atmospheric pressure plasma spray coating process.By evaluating the corrosion resistance of these materials,their applicability to environmentally friendly power generation equipment such as blades of tidal current turbines was examined.According to the Tafel analysis for micro-areas including the coating layer,the coating/metal interlayer and the base metal,the Al2O3-3TiO2 coating layer and the CoNiCrAlY coating layer show markedly lower corrosion current density than the base metal.The corrosion current density of the CoNiCrAlY coating layer (9.75316×10-8A/cm2) is about 1.6 times more than that of the Al2O3-3TiO2 coating layer (6.13139×10-8A/cm2).展开更多
基金Supported by the National High Technology Research and Development Programme of China(No.2011AA01A102)
文摘The rapid growth of streaming media applications on the Internet is proposing higher requirements on energy consumption and I/O performance of the storage systems.However,the optimized I/O requests from different initiators will be mixed disorderly when they are reaching the storage system concurrently,which leads to increasing energy consumption.This paper proposes an energy-saving scheduling scheme based on I/O Stream(ES-IOS).The ES-IOS scheme can take the advantage of the I/O characteristics of streaming media and reorganize the mixed and disordered I/O requests into "streams".Technically,The ES-IOS scheme includes two main points,a priority-based weighted stream scheduling algorithm(PWSS) and a regression-fitting-based popularity prediction algorithm(RFPP).The PWSS algorithm can schedule the I/O streams in weighted queue based on priority to limit energy consumption.The priority of each stream is determined by its popularity.According to the I/O access records over a period,the RFPP algorithm can predict the popularity of each stream via regression fitting.Based on the popularities,the PWSS algorithm assigns more continuous service time to the hot streams and reversely less service time to the cold ones.Trace-driven experiments show that the ES-IOS scheme can reduce the energy consumption by 38%and enhance the I/O throughput by 27%approximately.
文摘Project-based learning has been in widespread use in education. However, project managers are unaware of the students’ lack of experience and treat them as if they were professional staff. This paper proposes the application of a fuzzy failure mode and effects analysis model for project-based software engineering education. This method integrates the fuzzy rule-based system with learning agents. The agents construct the membership function from historical data. Data are processed by a clustering process that facilitates the construction of the membership function. It helps students who lack experience in risk assessment to develop their expertise in that skill. The paper also suggests a classification technique for a fuzzy rule-based system that can be used to judge risk based on a fuzzy inference system. The student project will thus be further enhanced with respect to risk assessment. We then discuss the design of experiments to verify the proposed model.
基金Supported by the Public Welfare Technology Application Research Project of Zhejiang Province(No.LTGY23F020001)the Provincial Construction Programme for First-Class Online and Offline Blended Courses(No.Z202Y22513)the Higher Education Teaching Reform Research Programme of Communication University of Zhejiang“Research on Contextualized Teaching Mode for the New Generation of Engineering Students Based on Convergence Media”。
文摘Background Autism spectrum disorder(ASD)is a pervasive developmental disorder characterized by difficulties in social communication and restricted,repetitive behaviors.Early intervention is essential to improve developmental outcomes in children with ASD.Serious games,which combine educational objectives with game based interactions,have shown potential as tools for early intervention in patients with ASD.However,in China,the development of serious games specifically designed for children with ASD remains in its infancy,with significant gaps in technical frameworks and effective data management methods.Method This paper proposes a framework aimed at facilitating the development of multimodal serious games designed for ASD interventions.We demonstrated the feasibility of the framework by developing and integrating several components,such as web applications,mobile games,and augmented reality games.These tools are interconnected to achieve data connectivity and management.Additionally,adaptive mechanics were employed within the framework to analyze real-time player data,which allowed the game difficulty to be dynamically adjusted and provide a personalized experience for each child.Results The framework successfully integrated various multimodal games,ensuring that real-time data management supported personalized game experiences.This approach ensured that the interventions remained appropriately challenging while still achievable.Conclusion The results indicate that the proposed framework enhances collaboration among therapists,parents,and developers while also improving the effectiveness of ASD interventions.By delivering personalized gameplay experiences that are both challenging and achievable,the framework offers a scalable platform for the future development of serious games.
基金financed by the European Union-NextGenerationEU,through the National Recowery and Resilience Plan of the Republic of Bulgaria,Project No.BG-RRP-2.013-0001-C01.
文摘Social media has emerged as one of the most transformative developments on the internet,revolu-tionizing the way people communicate and interact.However,alongside its benefits,social media has also given rise to significant challenges,one of the most pressing being cyberbullying.This issue has become a major concern in modern society,particularly due to its profound negative impacts on the mental health and well-being of its victims.In the Arab world,where social media usage is exceptionblly high,cyberbullying has become increasingly prevalent,necessitating urgent attention.Early detection of harmful online behavior is critical to fostering safer digital environments and mitigating the adverse efcts of cyberbullying.This underscores the importance of developing advanced tools and systems to identify and address such behavior efectively.This paper investigates the development of a robust cyberbullying detection and classifcation system tailored for Arabic comments on YouTube.The study explores the efectiveness of various deep learning models,including Bi-LSTM(Bidirectional Long Short Term Memory),LSTM(Long Short-Term Memory),CNN(Convolutional Neural Networks),and a hybrid CNN-LSTM,in classifying Arabic comments into binary classes(bullying or not)and multiclass categories.A comprehensive dataset of 20,000 Arabic YouTube comments was collected,preprocessed,and labeled to support these tasks.The results revealed that the CNN and hybrid CNN-LSTM models achieved the highest accuracy in binary classification,reaching an impressive 91.9%.For multiclass dlassification,the LSTM and Bi-LSTM models outperformed others,achieving an accuracy of 89.5%.These findings highlight the efctiveness of deep learning approaches in the mitigation of cyberbullying within Arabic online communities.
文摘为了改善软件的质量和生产性,注目于与其密切相关的软件结构.首先,讨论了现有方法中软件结构分析和设计的问题;然后根据质量设计中的质量屋HOQ(house of quality)与产品设计中的工程图之间的相似性,将质量功能展开QFD(quality function deployment)中的质量屋HOQ概念扩展成一种软件描述工具,并引入H.A.西蒙的系统准分解可能性原理,提出了基于数量化理论3类QMT3(quantification method of type 3)的软件定量结构化方法,再通过与现有方法的比较分析,阐明了该方法的特点;最后,通过应用实例验证了该方法对软件结构分析和设计的有效性.因而为软件质量保证提供了有力的支持.
基金co-supported by the Fundamental Research Funds for the Central Universities of China,China Postdoctoral Science Foundation(No.2018M631196)the National Natural Foundation of China(No.51705420).
文摘Multi-faults detection is a challenge for rolling bearings due to the mode mixture and coupling of multiple fault features,as well as its easy burying in the complex,non-stationary structural vibrations and strong background noises.In this paper,a method based on the flexible analytical wavelet transform(FAWT)possessing fractional scaling and translation factors is proposed to identify multiple faults occurred in different components of rolling bearings.During the route of the proposed method,the proper FAWT bases are constructed via genetic optimization algorithm(GA)based on maximizing the spectral correlated kurtosis(SCK)which is firstly presented and proved to be efficient and effective in indicating interested fault mode.Via using the customized FAWT bases for each interested fault mode,the original vibration measurements are decomposed into fine frequency subbands,and the sensitive subband which enhances the signal-to-noise ratio(SNR)is selected to exhibit the fault signature on its envelope spectrum.The proposed method is tested via simulated signals,and applied to analyze the experimental vibration measurements from the running roller bearings subjected to outrace,inner-race and roller defects.The analysis results validate the effectiveness of the proposed method in identifying multi-faults occurred in different components of rolling bearings.
基金supported by the National Research Foundation of Korea(NRF)funded by the Korean Government,Republic of Korea(Nos.2020R1A2C1012439,2020R1A4A1019227,and 2018R1A2B6002849)。
文摘Global environmental problems have been increasing with the growth of the world economy and have become a crucial issue.To replace fossil fuels,sustainable and eco-friendly catalysts are required for the removal of organic pollutants.In this study,nickel ferrite(NiFe_(2)O_(4))was prepared using a simple wet-chemical synthesis,followed by calcination;bismuth phosphate(BiPO_(4))was also prepared using a hydrothermal method.Further,NiFe_(2)O_(4)/BiPO_(4)nanocomposites were prepared using a hydrothermal technique.Numerous characterization studies,such as structural,morphology,surface area,optical,photoluminescence,and photoelectrochemical investigations,were used to analyze NiFe_(2)O_(4)/BiPO_(4)nanocomposites.The morphology analysis indicated a successful decoration of BiPO_(4)nanorods on the surface of Ni Fe_(2)O_(4)nanoplate.Further,the bandgap of the NiFe_(2)O_(4)/BiPO_(4)nanocomposites was modified owing to the formation of a heterostructure.The as-prepared NiFe_(2)O_(4)/BiPO_(4)nanocomposite exhibited promising properties to be used as a novel heterostructure for tetracycline(TC)and Rhodamine B(Rh B)removal.The NiFe_(2)O_(4)/BiPO_(4)nanocomposite degrades TC(98%)and Rh B(99%)pollutants upon solar-light irradiation within 100 and 60 min,respectively.Moreover,the trapping experiments confirmed the Z-scheme approach of the prepared nanocomposites.The efficient separation and transfer of photogenerated electron-hole pairs rendered by the heterostructure were confirmed by utilizing electrochemical impedance spectroscopy,photocurrent experiments,and photoluminescence.Mott–Schottky measurements were used determine the positions of the conduction and valence bands of the samples,and the detailed mechanism of photocatalytic degradation of toxic pollutants was projected and discussed.
基金supported by National Natural Science Foundation of China(Nos.61174124,61233003 and 60935001)National High Technology Research and Development Program of China(863 Program)(No.2011AA01A102)
文摘In network service systems,satisfying quality of service(QoS)is one of the main objectives.Admission control and resource allocation strategy can be used to guarantee the QoS requirement.Based on partially observable Markov decision processes(POMDPs),this paper proposes a novel admission control model for video on demand(VOD)service systems with elastic QoS.Elastic QoS is also considered in resource allocation strategy.Policy gradient algorithm is often available to find the solution of POMDP problems,with a satisfactory convergence rate.Through numerical examples,it can be shown that the proposed admission control strategy has better performance than complete admission control strategy.
基金the NSFC project(Nos.U1805255,11704105)Heilongjiang PostdoctoralFund(No.LBH-Z17188)the Fundamental Research Funds of University in Heilongjiang Province(No.2017-KYYWF-0465)。
文摘The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit competitive fluorescence detection performance of chloride ion(Cl)in aqueous solutio n.Under the optimized conditions,the concentration of Cl could be quantitative analyzed with the Ag-PCN in a wide detection range from 0.5 mmol/L to 0.1 mol/L,with a low detection limitation of 0.06 mmol/L.It is confirmed that the fluorescence of PCN could be effectively decayed by the photoinduced charge transfer via the adsorbed Cl for trapping holes,mainly by means of the time-resolved fluorescence and surface photo voltage spectra.The porous structure and modified Ag promote the adsorption of Cl on resulting Ag-PCN,leading to excellent fluorescence detection for Cl.This work provides a feasible route to develop a fluorescence detection of Cl with g-C_(3)N_(4) nanosheets in environment water.
基金Project supported by the 2010 Yeungnam University Research Grant,Korea
文摘The measurement and prediction of gas pulsations are performed along the discharge pipeline of a reciprocating compressor for a refrigerator. A regression based experimental model of the one-dimensional acoustic field is developed. First, the conventional method for gas pulsation measurement and prediction, which separates the incident and reflected wave of acoustic waves traveling in the frequency domain, is discussed. Then, regression based on our proposed simple model, which is able to predict gas pulsation compared to the conventional method, is introduced for the analysis of a reciprocating compressor(The conventional method requires the value of sound speed in the piping line for the reciprocating compressor). A numerical prediction is made for the regression method. Three power spectrum values along the discharge pipeline are used for analysis, and two values are used for verification. Our results are in a good agreement with the conventional method.
文摘With no annealing treatment, cathodic polarization trends in 5083F A1 alloy revealed concentration polarization and activation polarization. However, the annealed specimens have lower current densities at corrosion protection potential compared to the non-annealed specimen. The results of SSRTs conducted in seawater at the applied potential range of-l.8 V to -0.5 V indicated that the maximum tensile strength, elongation, and time-to-fracture had high values at applied potentials of -0.7 to -1.4 V. The maximum tensile strength, elongation, and time-to-f？acture decreased when the potential values were beyond this range in either anodic or cathodic direction. In general, the increased shear lip caused by annealing treatment indicates elongation. Time-to-fracture would likely increase with elongation. Potentials between -0.5 V to -0.6 V were found to be in the region of stress corrosion cracking. The corrosion protection zone was determined to be -0.7 V to -J,4 V because these potential ranges produced good mechanical properties. Potential less than -1.4 V produced a fractured surface with a mixture of dimples （ductile fractures） and a quasi-cleavage pattern resulting from the effects of hydrogen gas.
基金Project supported by the Ministry of Education,Science Technology(MEST) and Korea Industrial Technology Foundation(KOTEF) through the Human Resource Training Project for Regional Innovation
文摘Steel applied in ocean environment is exposed to corrosion and cavitation and is subject to increasing damages. To prevent this, anti-corrosion thermal spray coating technique is widely used. The low-temperature thermal spray coating was performed with 85%Al-14.5%Zn-0.5%Zr for ship materials and various sealing materials were applied to improve its durability, and the electrochemical behavior and cavitation characteristics were observed. The results show that the sealing improves all the properties of the materials. Hybrid ceramic and fluoro-silicon sealing materials show good electrochemical characteristics, and the fluoro-silieon sealing material shows the best anti-cavitation characteristics.
基金support from the EPSRC under grants EP/L014289/1 EP/N032888/1 and EP/M014045/1the STFC Global Challenges Network in Batteries and Electrochemical Energy Devices under the grant ST/N002385/1 for facilitation of travelfunding from the Royal Academy of Engineering
文摘Redox flow batteries offer a potential solution to an increase in renewable energy generation on the grid by offering long-term, large-scale storage and regulation of power. However, they are currently un- derutilised due to cost and performance issues, many of which are linked to the microstructure of the porous carbon electrodes used. Here, for the first time, we offer a detailed study of the in situ effects of compression on a commercially available carbon felt electrode. Visualisation of electrode structure us- ing X-ray computed tomography shows the non-linear way that these materials compress and various metrics are used to elucidate the changes in porosity, pore size distribution and tortuosity factor under compressions from 0%-90%.
基金Supported by the National High Technology Research and Development Program of China(No.2011AA01A102)the Important Science&Technology Project of Hainan Province(No.JDJS2013006,ZDXM2015103)the Young Talent Frontier Project of Institute of Acoustics,Chinese Academy of Sciences
文摘An integrated implementation framework of an intelligent recommendation system for outdoor video advertising is proposed, which is based on the analysis of audiences＇ characteristics. Firstly, the images of the scene and the people who view the video advertisements are captured by the net- work camera deployed on the video advertising terminal side. Then audiences＇ characteristics can be obtained by applying computer vision technologies ： face detection, face tracking, gender recogni- tion and age estimation. Finally, an intelligent recommendation algorithm is designed to decide the most fitting video ads for each terminal according to multi-dimensional statistical information of its reover, a novel face detection method and a new face tracking method have been proposed to meet the practical requirements of the system, of which the average Fl-score is O. 988 and 0. 951 respec- tively.
文摘The corrosions resulting from defects in painting layers frequently occur in Al alloys, so the application of corrosion preventing systems is also very important. Optimum conditions in terms of electrochemistry in relation to solution treatment, quenching and artificial aging treatment were established in order to optimize precipitation strengthening conditions intended to enhance the strength of Al alloys. Slow strain rate tests （SSRT） at various applied potentials were conducted in potential range from -1.8 to 0.5 V. The results show that the maximum tensile strengths, elongations and time-to-fracture are shown to be high values. After precipitation strengthening heat treatment, a tendency appear that time-to-fracture increases as elongation increases. In the potential range from -1.3 V to -0.7 V, the specimens show excellent mechanical properties, and thus this range is considered to be a corrosion prevention range.
文摘Medical image segmentation has consistently been a significant topic of research and a prominent goal,particularly in computer vision.Brain tumor research plays a major role in medical imaging applications by providing a tremendous amount of anatomical and functional knowledge that enhances and allows easy diagnosis and disease therapy preparation.To prevent or minimize manual segmentation error,automated tumor segmentation,and detection became the most demanding process for radiologists and physicians as the tumor often has complex structures.Many methods for detection and segmentation presently exist,but all lack high accuracy.This paper’s key contribution focuses on evaluating machine learning techniques that are supposed to reduce the effect of frequently found issues in brain tumor research.Furthermore,attention concentrated on the challenges related to level set segmentation.The study proposed in this paper uses the Population-based Artificial Bee Colony Clustering(P-ABCC)methodology to reliably collect initial contour points,which helps minimize the number of iterations and segmentation errors of the level-set process.The proposed model measures cluster centroids(ABC populations)and uses a level-set approach to resolve contour differences as brain tumors vary as they have irregular form,structure,and volume.The suggested model comprises of three major steps:first,pre-processing to separate the brain from the head and improves contrast stretching.Secondly,P-ABCC is used to obtain tumor edges that are utilized as an initial MRI sequence contour.The level-set segmentation is then used to detect tumor regions from all volume slices with fewer iterations.Results suggest improved model efficiency compared to state-of-the-art methods for both datasets BRATS 2019 and BRATS 2017.At BRATS 2019,dice progress was achieved for Entire Tumor(WT),Tumor Center(TC),and Improved Tumor(ET)by 0.03%,0.03%,and 0.01%respectively.At BRATS 2017,an increase in precision for WT was reached by 5.27%.
基金Project partially supported by the Ministry of Knowledge Economy (MKE) of Korea under the Information Technology Research Center (ITRC) Support Programthe Basic Research Program of the Korea Science (No. R01-2006-000-11214-0)
文摘Previously we have designed and implemented new image browsing facilities to support effective offiine image contents on mobile devices with limited capabilities： low bandwidth, small display, and slow processing. In this letter, we fulfill the automatic production of cartoon contents fitting small-screen display, and introduce a clustering method useful for various types of cartoon images as a prerequisite stage for preserving semantic meaning. The usage of neural networks is to properly cut the various forms of pages. Texture information that is useful for grayscale image segmentation gives us a good clue for page layout analysis using the multilayer perceptron （MLP） based x-y recursive algorithm. We also automatically frame the segment MLP using agglomerative segmentation. Our experimental results show that the combined approaches yield good results of segmentation for several cartoons.
文摘We consider the(2+1)-dimensional nonlinear Schrodinger equation with power-law nonlinearity under the parity-time-symmetry potential by using the Crank-Nicolson alternating direction implicit difference scheme,which can also be used to solve general boundary problems under the premise of ensuring accuracy.We use linear Fourier analysis to verify the unconditional stability of the scheme.To demonstrate the effectiveness of the scheme,we compare the numerical results with the exact soliton solutions.Moreover,by using the scheme,we test the stability of the solitons under the small environmental disturbances.
基金Project supported by the Ministry of Education,Science Technology(MEST)Korea Industrial Technology Foundation(KOTEF)through the Human Resource Training Project for Regional Innovation
文摘To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating layers by atmospheric pressure plasma spray coating process.By evaluating the corrosion resistance of these materials,their applicability to environmentally friendly power generation equipment such as blades of tidal current turbines was examined.According to the Tafel analysis for micro-areas including the coating layer,the coating/metal interlayer and the base metal,the Al2O3-3TiO2 coating layer and the CoNiCrAlY coating layer show markedly lower corrosion current density than the base metal.The corrosion current density of the CoNiCrAlY coating layer (9.75316×10-8A/cm2) is about 1.6 times more than that of the Al2O3-3TiO2 coating layer (6.13139×10-8A/cm2).
