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Design of an Efficient and Provable Secure Key Exchange Protocol for HTTP Cookies
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作者 Waseem Akram Khalid Mahmood +3 位作者 Hafiz Burhan ul Haq muhammad asif Shehzad Ashraf Chaudhry Taeshik Shon 《Computers, Materials & Continua》 SCIE EI 2024年第7期263-280,共18页
Cookies are considered a fundamental means of web application services for authenticating various Hypertext Transfer Protocol(HTTP)requests andmaintains the states of clients’information over the Internet.HTTP cookie... Cookies are considered a fundamental means of web application services for authenticating various Hypertext Transfer Protocol(HTTP)requests andmaintains the states of clients’information over the Internet.HTTP cookies are exploited to carry client patterns observed by a website.These client patterns facilitate the particular client’s future visit to the corresponding website.However,security and privacy are the primary concerns owing to the value of information over public channels and the storage of client information on the browser.Several protocols have been introduced that maintain HTTP cookies,but many of those fail to achieve the required security,or require a lot of resource overheads.In this article,we have introduced a lightweight Elliptic Curve Cryptographic(ECC)based protocol for authenticating client and server transactions to maintain the privacy and security of HTTP cookies.Our proposed protocol uses a secret key embedded within a cookie.The proposed protocol ismore efficient and lightweight than related protocols because of its reduced computation,storage,and communication costs.Moreover,the analysis presented in this paper confirms that proposed protocol resists various known attacks. 展开更多
关键词 COOKIES authentication protocol impersonation attack ECC
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A Novel Compact Highly Isolated UWB MIMO Antenna with WLAN Notch 被引量:1
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作者 muhammad Awais Shahid Bashir +3 位作者 Awais Khan muhammad asif Nasim Ullah Hend I.Alkhammash 《Computers, Materials & Continua》 SCIE EI 2023年第4期669-681,共13页
This paper presents a compact Multiple Input Multiple Output(MIMO)antenna with WLAN band notch for Ultra-Wideband(UWB)applications.The antenna is designed on 0.8mmthick low-cost FR-4 substrate having a compact size of... This paper presents a compact Multiple Input Multiple Output(MIMO)antenna with WLAN band notch for Ultra-Wideband(UWB)applications.The antenna is designed on 0.8mmthick low-cost FR-4 substrate having a compact size of 22mm×30 mm.The proposed antenna comprises of two monopole patches on the top layer of substrate while having a shared ground on its bottom layer.The mutual coupling between adjacent patches has been reduced by using a novel stub with shared ground structure.The stub consists of complementary rectangular slots that disturb the surface current direction and thus result in reducing mutual coupling between two ports.A slot is etched in the radiating patch for WLAN band notch.The slot is used to suppress frequencies ranging from 5.1 to 5.9 GHz.The results show that the proposed antenna has a very good impedance bandwidth of|S11|<−10 dB within the frequency band from 3.1–14 GHz.A low mutual coupling of less than−23 dB is achieved within the entire UWB band.Furthermore,the antenna has a peak gain of 5.8 dB,low ECC<0.002 and high Diversity Gain(DG>9.98). 展开更多
关键词 Multiple input multiple output(MIMO) ultra-wide band(UWB) defected ground structure envelope correlation coefficient diversity gain
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An Innovative Technique for Constructing Highly Non-Linear Components of Block Cipher for Data Security against Cyber Attacks 被引量:1
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作者 Abid Mahboob muhammad asif +4 位作者 Rana muhammad Zulqarnain Imran Siddique Hijaz Ahmad Sameh Askar Giovanni Pau 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2547-2562,共16页
The rapid advancement of data in web-based communication has created one of the biggest issues concerning the security of data carried over the internet from unauthorized access.To improve data security,modern cryptos... The rapid advancement of data in web-based communication has created one of the biggest issues concerning the security of data carried over the internet from unauthorized access.To improve data security,modern cryptosystems use substitution-boxes.Nowadays,data privacy has become a key concern for consumers who transfer sensitive data from one place to another.To address these problems,many companies rely on cryptographic techniques to secure data from illegal activities and assaults.Among these cryptographic approaches,AES is a well-known algorithm that transforms plain text into cipher text by employing substitution box(S-box).The S-box disguises the relationship between cipher text and the key to guard against cipher attacks.The security of a cipher using an S-box depends on the cryptographic strength of the respective S-box.Therefore,various researchers have employed different techniques to construct high order non-linear S-box.This paper provides a novel approach for evolving S-boxes using coset graphs for the action of the alternating group A5 over the finite field and the symmetric group S256.The motivation for this work is to study the symmetric group and coset graphs.The authors have performed various analyses against conventional security criteria such as nonlinearity,differential uniformity,linear probability,the bit independence criterion,and the strict avalanche criterion to determine its high cryptographic strength.To evaluate its image application performance,the proposed S-box is also used to encrypt digital images.The performance and comparison analyses show that the suggested S-box can secure data against cyber-attacks. 展开更多
关键词 Block cipher coset graphs S-BOX triangular group
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Blockchain and IIoT Enabled Solution for Social Distancing and Isolation Management to Prevent Pandemics
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作者 muhammad Saad Maaz Bin Ahmad +4 位作者 muhammad asif muhammad Khalid Khan Toqeer Mahmood Elsayed Tag Eldin Hala Abdel Hameed 《Computers, Materials & Continua》 SCIE EI 2023年第7期687-709,共23页
Pandemics have always been a nightmare for humanity,especially in developing countries.Forced lockdowns are considered one of the effective ways to deal with spreading such pandemics.Still,developing countries cannot ... Pandemics have always been a nightmare for humanity,especially in developing countries.Forced lockdowns are considered one of the effective ways to deal with spreading such pandemics.Still,developing countries cannot afford such solutions because these may severely damage the country’s econ-omy.Therefore,this study presents the proactive technological mechanisms for business organizations to run their standard business processes during pandemic-like situations smoothly.The novelty of this study is to provide a state-of-the-art solution to prevent pandemics using industrial internet of things(IIoT)and blockchain-enabled technologies.Compared to existing studies,the immutable and tamper-proof contact tracing and quarantine management solution is proposed.The use of advanced technologies and information security is a critical area for practitioners in the internet of things(IoT)and corresponding solutions.Therefore,this study also emphasizes information security,end-to-end solution,and experimental results.Firstly,a wearable wristband is proposed,incorporating 4G-enabled ultra-wideband(UWB)technology for smart contact tracing mechanisms in industries to comply with standard operating procedures outlined by the world health organization(WHO).Secondly,distributed ledger technology(DLT)omits the centralized dependency for transmitting contact tracing data.Thirdly,a privacy-preserving tracing mechanism is discussed using a public/private key cryptography-based authentication mechanism.Lastly,based on geofencing techniques,blockchain-enabled machine-to-machine(M2M)technology is proposed for quarantine management.The step-by-step methodology and test results are proposed to ensure contact tracing and quarantine management.Unlike existing research studies,the security aspect is also considered in the realm of blockchain.The practical implementation of the proposed solution also obtains the results.The results indicate the successful implementation of blockchain-enabled contact tracing and isolation management using IoT and geo-fencing techniques,which could help battle pandemic situations.Researchers can also consider the 5G-enabled narrowband internet of things(NB-IoT)technologies to implement contact tracing solutions. 展开更多
关键词 Blockchain contact tracing distributed ledger technology geo-fencing internet of things industrial internet of things isolation management social distancing ULTRA-WIDEBAND
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Aspect Level Songs Rating Based Upon Reviews in English
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作者 muhammad Aasim Qureshi muhammad asif +4 位作者 Saira Anwar Umar Shaukat Atta-ur-Rahman muhammad Adnan Khan Amir Mosavi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2589-2605,共17页
With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after ... With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after the use of the item.The enormous increase in these reviews has raised the need for an automated system to analyze these reviews to rate these items.Sentiment Analysis(SA)is a technique that performs such decision analysis.This research targets the ranking and rating through sentiment analysis of these reviews,on different aspects.As a case study,Songs are opted to design and test the decision model.Different aspects of songs namely music,lyrics,song,voice and video are picked.For the reason,reviews of 20 songs are scraped from YouTube,pre-processed and formed a dataset.Different machine learning algorithms—Naïve Bayes(NB),Gradient Boost Tree,Logistic Regression LR,K-Nearest Neighbors(KNN)and Artificial Neural Network(ANN)are applied.ANN performed the best with 74.99%accuracy.Results are validated using K-Fold. 展开更多
关键词 Machine learning natural language processing songs reviews:sentiment analysis songs rating aspect level sentiment analysis reviews analysis text classification MUSIC
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Zinc oxide nanoparticles accelerate the healing of methicillin-resistant Staphylococcus aureus(MRSA)-infected wounds in rabbits
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作者 muhammad asif Ayesha Safdar Chaudhry +4 位作者 Ambreen Ashar Hamad Bin Rashid muhammad Hassan Saleem Hassaan Bin Aslam Abdul Aziz 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第11期488-496,I0002,共10页
Objective:To synthesize zinc oxide nanoparticles(ZnONPs)and evaluate their antibacterial and wound healing effects against wounds infected with methicillin-resistant Staphylococcus aureus(MRSA).Methods:ZnONPs were pre... Objective:To synthesize zinc oxide nanoparticles(ZnONPs)and evaluate their antibacterial and wound healing effects against wounds infected with methicillin-resistant Staphylococcus aureus(MRSA).Methods:ZnONPs were prepared by sol-gel method and characterized by X-ray diffraction(XRD)analysis and scanning electron microscopy(SEM).A total of 18 rabbits were divided into three groups:the ZnONPs group,the gentamicin group and the control group.A wound of 3 cm^(2) was inflicted on each rabbit and contaminated with MRSA inoculum.Treatment was started from the fourth day post-surgery.Wound healing,microbiological analysis,and histopathological analysis were performed to assess the efficacy of ZnONPs ointment.Results:XRD analysis confirmed the hexagonal wurtzite structure of the ZnONPs with an average crystallite size of 29.23 nm.SEM revealed discoid-shaped ZnONPs with a rough surface and an average size of 48.36 nm.Energy-dispersive X-ray analysis confirmed the purity of ZnONPs.Moreover,the particle size ranged from 100-700 nm with a high agglomeration trend.Treatment with ZnONPs promoted MRSA-infected wound healing.In addition,ZnONPs showed a good antibacterial effect as evidenced by a dose-dependent increase in the zone of inhibition.Conclusions:ZnONPs accelerate the healing of MRSA-infected wounds.Therefore,it can be explored for the treatment of MRSA infection. 展开更多
关键词 MRSA Wound healing ZnO NANOPARTICLES OINTMENT
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A Mathematical Approach for Generating a Highly Non-Linear Substitution Box Using Quadratic Fractional Transformation
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作者 Abid Mahboob muhammad asif +3 位作者 Rana muhammad Zulqarnain Imran Saddique Hijaz Ahmad Sameh Askar 《Computers, Materials & Continua》 SCIE EI 2023年第11期2565-2578,共14页
Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illeg... Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illegal activities and assaults.Modern cryptographic ciphers use the non-linear component of block cipher to ensure the robust encryption process and lawful decoding of plain data during the decryption phase.For the designing of a secure substitution box(S-box),non-linearity(NL)which is an algebraic property of the S-box has great importance.Consequently,the main focus of cryptographers is to achieve the S-box with a high value of non-linearity.In this suggested study,an algebraic approach for the construction of 16×16 S-boxes is provided which is based on the fractional transformation Q(z)=1/α(z)^(m)+β(mod257)and finite field.This technique is only applicable for the even number exponent in the range(2-254)that are not multiples of 4.Firstly,we choose a quadratic fractional transformation,swap each missing element with repeating elements,and acquire the initial S-box.In the second stage,a special permutation of the symmetric group S256 is utilized to construct the final S-box,which has a higher NL score of 112.75 than the Advanced Encryption Standard(AES)S-box and a lower linear probability score of 0.1328.In addition,a tabular and graphical comparison of various algebraic features of the created S-box with many other S-boxes from the literature is provided which verifies that the created S-box has the ability and is good enough to withstand linear and differential attacks.From different analyses,it is ensured that the proposed S-boxes are better than as compared to the existing S-boxes.Further these S-boxes can be utilized in the security of the image data and the text data. 展开更多
关键词 Block cipher S-BOX data security fractional transformation
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Appearance Based Dynamic Hand Gesture Recognition Using 3D Separable Convolutional Neural Network
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作者 muhammad Rizwan Sana Ul Haq +4 位作者 Noor Gul muhammad asif Syed Muslim Shah Tariqullah Jan Naveed Ahmad 《Computers, Materials & Continua》 SCIE EI 2023年第7期1213-1247,共35页
Appearance-based dynamic Hand Gesture Recognition(HGR)remains a prominent area of research in Human-Computer Interaction(HCI).Numerous environmental and computational constraints limit its real-time deployment.In addi... Appearance-based dynamic Hand Gesture Recognition(HGR)remains a prominent area of research in Human-Computer Interaction(HCI).Numerous environmental and computational constraints limit its real-time deployment.In addition,the performance of a model decreases as the subject’s distance from the camera increases.This study proposes a 3D separable Convolutional Neural Network(CNN),considering the model’s computa-tional complexity and recognition accuracy.The 20BN-Jester dataset was used to train the model for six gesture classes.After achieving the best offline recognition accuracy of 94.39%,the model was deployed in real-time while considering the subject’s attention,the instant of performing a gesture,and the subject’s distance from the camera.Despite being discussed in numerous research articles,the distance factor remains unresolved in real-time deployment,which leads to degraded recognition results.In the proposed approach,the distance calculation substantially improves the classification performance by reducing the impact of the subject’s distance from the camera.Additionally,the capability of feature extraction,degree of relevance,and statistical significance of the proposed model against other state-of-the-art models were validated using t-distributed Stochastic Neighbor Embedding(t-SNE),Mathew’s Correlation Coefficient(MCC),and the McNemar test,respectively.We observed that the proposed model exhibits state-of-the-art outcomes and a comparatively high significance level. 展开更多
关键词 3D separable CNN computational complexity hand gesture recognition human-computer interaction
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NewBee: Context-Free Grammar (CFG) of a New Programming Language for Novice Programmers
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作者 muhammad Aasim Qureshi muhammad asif Saira Anwar 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期439-453,共15页
Learning programming and using programming languages are the essential aspects of computer science education.Students use programming languages to write their programs.These computer programs(students or practitioners... Learning programming and using programming languages are the essential aspects of computer science education.Students use programming languages to write their programs.These computer programs(students or practitioners written)make computers artificially intelligent and perform the tasks needed by the users.Without these programs,the computer may be visioned as a pointless machine.As the premise of writing programs is situated with specific programming languages,enormous efforts have been made to develop and create programming languages.However,each program-ming language is domain-specific and has its nuances,syntax and seman-tics,with specific pros and cons.These language-specific details,including syntax and semantics,are significant hurdles for novice programmers.Also,the instructors of introductory programming courses find these language specificities as the biggest hurdle in students learning,where more focus is on syntax than logic development and actual implementation of the program.Considering the conceptual difficulty of programming languages and novice students’struggles with the language syntax,this paper describes the design and development of a Context-Free Grammar(CFG)of a programming language for the novice,newcomers and students who do not have computer science as their major.Due to its syntax proximity to daily conversations,this paper hypothesizes that this language will be easy to use and understand by novice programmers.This paper systematically designed the language by identifying themes from various existing programming languages(e.g.,C,Python).Additionally,this paper surveyed computer science experts from industry and academia,where experts self-reported their satisfaction with the newly designed language.The results indicate that 93%of the experts reported satisfaction with the NewBee for novice,newcomer and non-Computer Sci-ence(CS)major students. 展开更多
关键词 Programming language formal language computer language language grammar simple syntax programming language novice programmer
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Identification and Visualization of Spatial and Temporal Trends in Textile Industry
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作者 Umair Yousaf muhammad asif +6 位作者 Shahbaz Ahmed Noman Tahir Azeem Irshad Akber Abid Gardezi muhammad Shafiq Jin-Ghoo Choi Habib Hamam 《Computers, Materials & Continua》 SCIE EI 2023年第2期4165-4181,共17页
The research volume increases at the study rate,causing massive text corpora.Due to these enormous text corpora,we are drowning in data and starving for information.Therefore,recent research employed different text mi... The research volume increases at the study rate,causing massive text corpora.Due to these enormous text corpora,we are drowning in data and starving for information.Therefore,recent research employed different text mining approaches to extract information from this text corpus.These proposed approaches extract meaningful and precise phrases that effectively describe the text’s information.These extracted phrases are commonly termed keyphrases.Further,these key phrases are employed to determine the different fields of study trends.Moreover,these key phrases can also be used to determine the spatiotemporal trends in the various research fields.In this research,the progress of a research field can be better revealed through spatiotemporal bibliographic trend analysis.Therefore,an effective spatiotemporal trend extraction mechanism is required to disclose textile research trends of particular regions during a specific period.This study collected a diversified dataset of textile research from 2011–2019 and different countries to determine the research trend.This data was collected from various open access journals.Further,this research determined the spatiotemporal trends using quality phrasemining.This research also focused on finding the research collaboration of different countries in a particular research subject.The research collaborations of other countries’researchers show the impact on import and export of those countries.The visualization approach is also incorporated to understand the results better. 展开更多
关键词 Text mining spatiotemporal trend research collaboration
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Sustainable Learning of Computer Programming Languages Using Mind Mapping
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作者 Shahla Gul muhammad asif +6 位作者 Zubair Nawaz muhammad Haris Aziz Shahzada Khurram muhammad Qaiser Saleem Elturabi Osman Ahmed Habib muhammad Shafiq Osama E.Sheta 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1687-1697,共11页
In the current era of information technology,students need to learn modern programming languages efficiently.The art of teaching/learning program-ming requires many logical and conceptual skills.So it’s a challenging ... In the current era of information technology,students need to learn modern programming languages efficiently.The art of teaching/learning program-ming requires many logical and conceptual skills.So it’s a challenging task for the instructors/learners to teach/learn these programming languages effectively and efficiently.Mind mapping is a useful visual tool for establishing ideas and connecting them to solve problems.This research proposed an effective way to teach programming languages through visual tools.This experimental study uses a mind mapping tool to teach two programming environments:Text-based Programming and Blocks-based Programming.We performed the experiments with one hundred and sixty undergraduate students of two public sector universities in the Asia Pacific region.Four different instructional approaches,including block-based language(BBL),text-based languages(TBL),mind map with text-based language(MMTBL)and mind mapping with block-based(MMBBL)are used for this purpose.The results show that instructional approaches using a mind mapping tool to help students solve given tasks in their critical thinking are more effective than other instructional techniques. 展开更多
关键词 Text programming blocks programming novice programmer
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Effect of SiN:H_x passivation layer on the reverse gate leakage current in GaN HEMTs
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作者 张昇 魏珂 +9 位作者 肖洋 马晓华 张一川 刘果果 雷天民 郑英奎 黄森 汪宁 muhammad asif 刘新宇 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期540-544,共5页
This paper concentrates on the impact of SiN passivation layer deposited by plasma-enhanced chemical vapor deposition(PECVD) on the Schottky characteristics in GaN high electron mobility transistors(HEMTs). Three ... This paper concentrates on the impact of SiN passivation layer deposited by plasma-enhanced chemical vapor deposition(PECVD) on the Schottky characteristics in GaN high electron mobility transistors(HEMTs). Three types of SiN layers with different deposition conditions were deposited on GaN HEMTs. Atomic force microscope(AFM), capacitance-voltage(C-V), and Fourier transform infrared(FTIR) measurement were used to analyze the surface morphology, the electrical characterization, and the chemical bonding of SiN thin films, respectively. The better surface morphology was achieved from the device with lower gate leakage current. The fixed positive charge Qf was extracted from C-V curves of Al/SiN/Si structures and quite different density of trap states(in the order of magnitude of 1011-1012 cm^(-2)) was observed.It was found that the least trap states were in accordance with the lowest gate leakage current. Furthermore, the chemical bonds and the %H in Si-H and N-H were figured from FTIR measurement, demonstrating an increase in the density of Qf with the increasing %H in N-H. It reveals that the effect of SiN passivation can be improved in GaN-based HEMTs by modulating %H in Si-H and N-H, thus achieving a better Schottky characteristics. 展开更多
关键词 SiN passivation the gate leakage current QF FTIR
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Forensics Issues in Cloud Computing
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作者 Aqil Burney muhammad asif Zain Abbas 《Journal of Computer and Communications》 2016年第10期63-69,共7页
Cloud computing is an emerging technology that is being widely adopted throughout the world due to its ease-of-use. Organizations of all types can use it without pre-requisites such as IT infra-structure, technical sk... Cloud computing is an emerging technology that is being widely adopted throughout the world due to its ease-of-use. Organizations of all types can use it without pre-requisites such as IT infra-structure, technical skills, managerial overload, storage capacity, processing power, and data recovery or privacy setup. It can be availed by all clients as per their needs, expectations and budget. However, cloud computing introduces new kinds of security vulnerabilities that need to be ad-dressed. Traditional “Computer Forensics” deals with detection, preemption and prevention of IT triggered frauds and crimes but it lacks the ability to deal with cybercrimes pertaining to cloud computing environment. In this paper, we focus on forensics issues in cloud computing, assess limitations of forensic team and present the obstacles faced during investigation. 展开更多
关键词 Computer Forensics Cloud Computing Cybercrimes Cloud Security Cloud Service Provider
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W波段InP DHBT宽带高功率压控振荡器(英文) 被引量:2
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作者 王溪 姚鸿飞 +5 位作者 苏永波 丁武昌 阿瑟夫 丁芃 童志航 金智 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2019年第1期27-31,43,共6页
成功实现了一款具有高输出功率和宽频率调谐范围的基波压控振荡器.其制作工艺为0. 8μm InP DH-BT工艺,晶体管的最大fT和fmax分别为170和250 GHz.电路核心部分采用了为高频应用改进的平衡式考毕兹拓扑,在后面添加一级缓冲放大器来抑制... 成功实现了一款具有高输出功率和宽频率调谐范围的基波压控振荡器.其制作工艺为0. 8μm InP DH-BT工艺,晶体管的最大fT和fmax分别为170和250 GHz.电路核心部分采用了为高频应用改进的平衡式考毕兹拓扑,在后面添加一级缓冲放大器来抑制负载牵引效应,并提升了输出功率. DHBT的反偏CB结作为变容二极管来实现频率调谐.芯片测试结果表明,压控振荡器的频率调谐范围为81~97. 3 GHz,相对带宽为18. 3%.在调谐频率范围内最大输出功率为10. 2 dBm,输出功率起伏在3. 5 dB以内.在该压控振荡器的最大调谐频率97. 3 GHz处相位噪声为-88 dBc/Hz@1MHz. 展开更多
关键词 压控振荡器 磷化铟双异质结晶体管 宽调谐范围 高输出功率
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Effect of graphene nanoplatelets(GNPs)addition on strength and ductility of magnesium-titanium alloys 被引量:10
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作者 muhammad Rashad Fusheng Pan +6 位作者 Aitao Tang Yun Lu muhammad asif Shahid Hussain Jia She Jun Gou Jianjun Mao 《Journal of Magnesium and Alloys》 SCIE EI CAS 2013年第3期242-248,共7页
Effect of graphene nanoplatelets(GNPs)addition on mechanical properties of magnesium–10wt%Titanium(Mg–10Ti)alloy is investigated in current work.The Mg-(10Ti+0.18GNPs)composite was synthesized using the semi powder ... Effect of graphene nanoplatelets(GNPs)addition on mechanical properties of magnesium–10wt%Titanium(Mg–10Ti)alloy is investigated in current work.The Mg-(10Ti+0.18GNPs)composite was synthesized using the semi powder metallurgy method followed by hot extrusion.Microstructural characterization results revealed the uniform distribution of reinforcement(Ti+GNPs)particles in the matrix,therefore(Ti+GNPs)particles act as an effective reinforcing filler to prevent the deformation.Room temperature tensile results showed that the addition of Ti+GNPs to monolithic Mg lead to increase in 0.2%yield strength(0.2%YS),ultimate tensile strength(UTS),and failure strain.Scanning Electron Microscopy(SEM),Energy-Dispersive X-ray Spectroscopy(EDS)and X-Ray Diffraction(XRD)were used to investigate the surface morphology,elemental dispersion and phase analysis,respectively. 展开更多
关键词 MAGNESIUM Titanium Graphene nanoplatelets Alloy Composite materials Powder metallurgy Mechanical properties
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High temperature formability of graphene nanoplatelets-AZ31 composites fabricated by stir-casting method 被引量:12
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作者 muhammad Rashad Fusheng Pan +5 位作者 Yanglu Liu Xianhua Chen Han Lin Rongjian Pan muhammad asif Jia She 《Journal of Magnesium and Alloys》 SCIE EI CAS 2016年第4期270-277,共8页
Outstanding mechanical properties of graphene nanoplatelets(GNPs)make them ideal reinforcement for mass production of composites.In this research,the composites were fabricated by stir-casting method.GNPs were added i... Outstanding mechanical properties of graphene nanoplatelets(GNPs)make them ideal reinforcement for mass production of composites.In this research,the composites were fabricated by stir-casting method.GNPs were added in 1.5 and 3.0 wt.%into Mg–3wt.%Al–1wt.%Zn(AZ31)magnesium alloy.As cast ingots were preheated for one hour and extruded at 350℃ with extrusion ratio of 5.2:1.As extruded AZ31-GNPs composites were micro-structurally characterized with X-ray diffraction,optical microscopy and scanning electron microscopy.Vickers microhardness of synthesized materials was investigated both in parallel and perpendicular to extrusion directions.Room temperature mechanical testing revealed that with increasing GNP’s content,tensile fracture strain was remarkably increased without significant compromise in tensile strength.Furthermore,as extruded AZ31-3GNPs composites were subjected to tensile testing at temperatures ranging from 75℃ to 300℃ with initial strain rate of 2×10^(−3)s^(−1) to evaluate high temperature formability of composite.It was found that like CNTs,GNPs also have the potential to sustain tensile strength at high temperatures. 展开更多
关键词 Metal matrix composites Mechanical properties Stir-casting method Elevated temperatures
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Pore size distribution,their geometry and connectivity in deeply buried Paleogene Es1 sandstone reservoir,Nanpu Sag,East China 被引量:4
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作者 muhammad Kashif Yingchang Cao +5 位作者 Guanghui Yuan muhammad asif Kamran Javed Jose Nicanor Mendez Danish Khan Lin Miruo 《Petroleum Science》 SCIE CAS CSCD 2019年第5期981-1000,共20页
The study or pore characteristics is or great importance in reservoir evaluation,especially in deeply buried s andstone.It controls the storage mechanism and reservoir fluid properties of the permeable horizons.The fi... The study or pore characteristics is or great importance in reservoir evaluation,especially in deeply buried s andstone.It controls the storage mechanism and reservoir fluid properties of the permeable horizons.The first member of Eocene Shahejie Formation(Esl)sandstone is classified as feldspathic litharenite and lithic arkose.The present research investigates the pore characteristics and reservoir features of the deeply buried sandstone reservoir of Esl member of Shahejie Formation.The techniques including thin-section petrography,mercury injection capillary pressure(MICP),scanning electron microscopy and laser scanning confocal microscope images were used to demarcate the pores including primary intergranular pores and secondary intergranular,intragranular,dissolution and fracture pores.Mercury injection test and routine core analysis were led to demarcate the pore network characteristics of the studied reservoir.Pore size and pore throat size distribution are acquired from mercury injection test.Porosity values range from 0.5%to 30%,and permeability ranges 0.006-7000 mD.Pore radii of coarse-grained sandstone and fine-grained sandstone range from 0.2 to>4μm and 1 nm to 1.60μm,respectively,by MICP analysis.The mineral composition also plays an important role in protecting the pores with pressure from failure.Fractured sandstone and coarse-grained sandstone consist of large and interconnected pores that enhance the reservoir porosity and permeability,whereas fine-grained sandstone and siltstone consist of numerous pores but not well interconnected,and so they consist of high porosity with low permeability. 展开更多
关键词 Reservoir rock Pore characteristics Pore size distribution Pore throat POROSITY PERMEABILITY
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Quest for carbon and vanadium oxide based rechargeable magnesium-ion batteries 被引量:5
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作者 muhammad Rashad muhammad asif +4 位作者 Iftikhar Ahmed Zhen He Li Yin Zhou Xiao Wei Yuxin Wang 《Journal of Magnesium and Alloys》 SCIE 2020年第2期364-373,共10页
Rechargeable magnesium ion batteries are potential candidates to replace the lithium ion batteries due to their high volumetric energy density,dendrite free cycling,and low costs.In present work,we have critically rev... Rechargeable magnesium ion batteries are potential candidates to replace the lithium ion batteries due to their high volumetric energy density,dendrite free cycling,and low costs.In present work,we have critically reviewed the recent advances made in the field of cathode materials development to achieve the high reversible capacities and working potentials.In first part,carbon-based cathodes such as fluorinedoped graphene nanosheets and graphite fluoride(CF0.8)are discussed in terms of compatibilities of pos让ive electrode materials and electrolyte solutions for rechargeable magnesium-ion batteries.Whereas,the second part of this review focuses on crystal structure of vanadium oxide and its capability to accommodate the Mg^2+ions.Likewise,electrochemical performance of selected vanadium oxide based cathodes including VO2(B),FeVO4.0.9H2(X Mc)2.5+yVO9+δ,RFC/V2O5 and V2O5/Graphene composite,are discussed at different temperatures.To support the future research on magnesium ion batteries,particularly positive electrode material developments,several innovative research directions are proposed. 展开更多
关键词 Magnesium-ion battery Energy storage Cathode materials Electrolytes Vanadium oxide Electrochemical properties
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Improved mechanical proprieties of“magnesium based composites”with titaniume-aluminum hybrids 被引量:5
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作者 muhammad Rashad Fusheng Pan +2 位作者 muhammad asif Jia She Ahsan Ullah 《Journal of Magnesium and Alloys》 SCIE EI CAS 2015年第1期1-9,共9页
In this study,the effect of micron-sized titanium and aluminum addition on the microstructural,mechanical and work-hardening behavior of pure Mg is investigated.Pure Mg reinforced with 10%Ti and 10%Ti-1%Al particulate... In this study,the effect of micron-sized titanium and aluminum addition on the microstructural,mechanical and work-hardening behavior of pure Mg is investigated.Pure Mg reinforced with 10%Ti and 10%Ti-1%Al particulates were synthesized through semi-powder metallurgy route followed by hot extrusion.Semi-powder metallurgy appears to be promising approach for the synthesis of Mg based composite,as it is free of ball milling.Tensile results indicate that the direct addition of micron-sized 10wt.%titanium particulates to pure Mg,caused an improvement in elastic modulus,0.2%yield strength,ultimate tensile strength,and failure strain(+72%;+41%;+29%;and+79%respectively).The addition of micron-sized 10wt.%titanium particles along with 1.0wt.%Al particles to pure Mg,resulted in an enhancement in elastic modulus,0.2%yield strength,ultimate tensile strength,and failure strain(+74%;+56%;+45%;and+241%respectively).Besides tensile test,Vickers hardness and work-hardening behavior of prepared composites were also examined.Impressive failure strain of Mg-10Ti-1Al composite can be attributed to the better compatibility of Ti particulates with Mg due to presence of alloying element Al. 展开更多
关键词 Mechanical properties MICROSTRUCTURE Powder metallurgy method Metal matrix composite
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Corrosion behavior of magnesium-graphene composites in sodium chloride solutions 被引量:4
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作者 muhammad Rashad Fusheng Pan +1 位作者 muhammad asif Xianhua Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS 2017年第3期271-276,共6页
Coating of graphene and graphene/polymer composites on metals improves the corrosion resistance of metal substrates.On other hand,graphene embedded inside metal(especially Mg)matrices increases or decreases corrosion,... Coating of graphene and graphene/polymer composites on metals improves the corrosion resistance of metal substrates.On other hand,graphene embedded inside metal(especially Mg)matrices increases or decreases corrosion,is a crucial factor and must be explored.In present study,electrochemical behaviors of magnesium alloys(AZ31 and AZ61)and their composites reinforced with graphene nanoplatelets(GNPs)were carried out in 3.5%NaCl solution by polarization method.The surface morphology of composites before and after corrosion tests were analyzed using scanning electron microscopy.Experimental results revealed that presence of graphene nanoplatelets in different matrices decrease corrosion resistance of composites.This may be attributed to presence of graphene nanoplatelets which activates the corrosion of magnesium/alloys due to the occurrence of galvanic corrosion and this effect increases with increasing graphene nanoplatelets content.Further,an appropriate model describing the corrosion mechanism was proposed. 展开更多
关键词 Metal matrix composites Electro-chemical properties Corrosion
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