In this study,we fabricate Si/SiGe core-shell Junctionless accumulation mode(JAM)FinFET devices through a rapid and novel process with four main steps,i.e.e-beam lithography definition,sputter deposition,alloy combina...In this study,we fabricate Si/SiGe core-shell Junctionless accumulation mode(JAM)FinFET devices through a rapid and novel process with four main steps,i.e.e-beam lithography definition,sputter deposition,alloy combination annealing,and chemical solution etching.The height of Si core is 30 nm and the thickness of Si/SiGe core-shell is about 2 nm.After finishing the fabrication of devices,we widely studied the electrical characteristics of poly Si/SiGe core-shell JAM FinFET transistors from a view of different Lg and Wch.A poly-Si/SiGe core-shell JAMFETs was successfully demonstrated and it also exhibits a superior subthreshold swing of 81mV/dec and high on/off ratio>10^5 when annealing for 1hr at 600℃.The thermal diffusion process condition for this study are 1hr at 600℃ and 6hr at 700℃ for comparison.The annealing condition at 700oC for 6 hours shows undesired electrical characteristics against the other.Results suggests that from over thermal budget causes a plenty of Ge to precipitate against to form SiGe thin film.Annealing JAMFETs at low temperature shows outstanding Subthreshold swing and better swing condition when compared to its counterpart i.e.at higher temperature.This new process can still fabricate a comparable performance to classical planar FinFET in driving current.展开更多
The authors fulfilled calculations of the total energy and electronic states of Cd_(n)Se_(n) nanoparticle:“wurzite”,“sphalerite”and“rock-salt”types of the structure.It was shown that at n≤72 the“rock-salt”typ...The authors fulfilled calculations of the total energy and electronic states of Cd_(n)Se_(n) nanoparticle:“wurzite”,“sphalerite”and“rock-salt”types of the structure.It was shown that at n≤72 the“rock-salt”type is the most favorable energetically.However the extrapolation of the behavior of the energy per Cd-Se atomic pair shows that for n>130(corresponding to a size of about 2 nm),particles with a“wurtzite”structure can be more advantageous.Particles of the“wurtzite”and“rock-salt”types have an electronic structure with an energy gap.For particles with the“wurtzite”structure,the gap width decreases with increasing particle size:from 3.3 eV to 2.2 eV as the particle increases from 0.5 nm to 1.5 nm.For particles of the“rock-salt”type,the gap width grows slightly,remaining about 3 eV.“Sphalerite”-type particles have a metal-like electronic structure.展开更多
The proliferation of cloud computing and internet of things has led to the connectivity of states and nations(developed and developing countries)worldwide in which global network provide platform for the connection.Di...The proliferation of cloud computing and internet of things has led to the connectivity of states and nations(developed and developing countries)worldwide in which global network provide platform for the connection.Digital forensics is a field of computer security that uses software applications and standard guidelines which support the extraction of evidences from any computer appliances which is perfectly enough for the court of law to use and make a judgment based on the comprehensiveness,authenticity and objectivity of the information obtained.Cybersecurity is of major concerned to the internet users worldwide due to the recent form of attacks,threat,viruses,intrusion among others going on every day among internet of things.However,it is noted that cybersecurity is based on confidentiality,integrity and validity of data.The aim of this work is make a systematic review on the application of machine learning algorithms to cybersecurity and cyber forensics and pave away for further research directions on the application of deep learning,computational intelligence,soft computing to cybersecurity and cyber forensics.展开更多
This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that fol...This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.展开更多
Detecting the presence of a valid signal is an important task of a telecommunication receiver.When the receiver is unable to detect the presence of a valid signal,due to noise and fading,it is referred to as an erasur...Detecting the presence of a valid signal is an important task of a telecommunication receiver.When the receiver is unable to detect the presence of a valid signal,due to noise and fading,it is referred to as an erasure.This work deals with the probability of erasure computation for orthogonal frequency division multiplexed(OFDM)signals used by multiple input multiple output(MIMO)systems.The theoretical results are validated by computer simulations.OFDM is widely used in present day wireless communication systems due to its ability to mitigate intersymbol interference(ISI)caused by frequency selective fading channels.MIMO systems offer the advantage of spatial multiplexing,resulting in increased bit-rate,which is the main requirement of the recent wireless standards like 5G and beyond.展开更多
In this paper,a novel capacitor-inductor integrated structure was proposed.The dielectric material BaTiO3(BTO)and ferromagnetic material Ni0.5Zn0.5Fe2O4(NZFO)was prepared by sol-gel method.Phase composition and morpho...In this paper,a novel capacitor-inductor integrated structure was proposed.The dielectric material BaTiO3(BTO)and ferromagnetic material Ni0.5Zn0.5Fe2O4(NZFO)was prepared by sol-gel method.Phase composition and morphology of the thin films were characterized by XRD,SEM and AFM.The effect of annealing temperature on film crystallinity,surface morphology,dielectric properties and ferromagnetism was investigated.When the annealing temperature was 700°C,the BTO film and the NZFO film got the better dielectric properties and ferromagnetic properties.Then the BTO thin film was spin-coated on the substrate,and the NZFO thin film was in-situ sintered on the BTO thin film.The composite film possessed both ferromagnetism and dielectric properties.Finally,an inductive coil was fabricated on the BTO/NZFO composite film to produce a capacitance and inductance integrated device.展开更多
This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that fol...This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.展开更多
In this study,the impacts of internal heat generation on heat transfer enhancement of porous fin is theoretical investigated using differential transform method.The parametric studies reveal that porosity enhances the...In this study,the impacts of internal heat generation on heat transfer enhancement of porous fin is theoretical investigated using differential transform method.The parametric studies reveal that porosity enhances the fin heat dissipating capacity but the internal heat generation decreases the heat enhancement capacity of extended surface.Also,it is established that when the internal heat parameter increases to some certain values,some negative effects are recorded where the fin stores heat rather than dissipating it.This scenario defeats the prime purpose of the cooling fin.Additionally,it is established in the present study that the limiting value of porosity parameter for thermal stability for the passive device increases as internal heat parameter increases.This shows that although the internal heat parameter can help assist higher range and value of thermal stability of the fin,it produces negative effect which greatly defeats the ultimate purpose of the fin.The results in the work will help in fin design for industrial applications where internal heat generation is involved.展开更多
There’s a lot of value in data.The collection,fusion and mining of multi-source data will release the potential of data and bring into play the value of data.At the same time,due to their respective interests and ris...There’s a lot of value in data.The collection,fusion and mining of multi-source data will release the potential of data and bring into play the value of data.At the same time,due to their respective interests and risks of privacy exposure,there are obstacles in the development of multi-data fusion,and the phenomenon of“isolated data island”is common,which hinders the development of data fusion.展开更多
We report intrinsic photoconductivity studies on one of the least examined layered compounds,ZrS2.Few-atomic layer ZrS2 field-effect transistors were fabricated on the Si/SiO2 substrate and photoconductivity measureme...We report intrinsic photoconductivity studies on one of the least examined layered compounds,ZrS2.Few-atomic layer ZrS2 field-effect transistors were fabricated on the Si/SiO2 substrate and photoconductivity measurements were performed using both two-and four-terminal configurations under the illumination of 532 nm laser source.We measured photocurrent as a function of the incident optical power at several source-drain(bias)voltages.We observe a significantly large photoconductivity when measured in the multiterminal(four-terminal)configuration compared to that in the two-terminal configuration.For an incident optical power of 90 nW,the estimated photosensitivity and the external quantum efficiency(EQE)measured in two-terminal configuration are 0.5 A/W and 120%,respectively,under a bias voltage of 650 mV.Under the same conditions,the four-terminal measurements result in much higher values for both the photoresponsivity(R)and EQE to 6 A/W and 1400%,respectively.This significant improvement in photoresponsivity and EQE in the four-terminal configuration may have been influenced by the reduction of contact resistance at the metal-semiconductor interface,which greatly impacts the carrier mobility of low conducting materials.This suggests that photoconductivity measurements performed through the two-terminal configuration in previous studies on ZrS2 and other 2D materials have severely underestimated the true intrinsic properties of transition metal dichalcogenides and their remarkable potential for optoelectronic applications.展开更多
With apparent size and weight advantages,on-chip spectrometer could be a good choice for the spectrum analysis application which has been widely used in numerous areas such as optical network performance monitoring,ma...With apparent size and weight advantages,on-chip spectrometer could be a good choice for the spectrum analysis application which has been widely used in numerous areas such as optical network performance monitoring,materials analysis and medical research.In order to realize the broadband and the high resolution simultaneously,we propose a new on-chip spectrometer structure,which is a two-stage structure.The coarse wavelength division is realized by the cascaded Mach-Zehnder interferometers,which is the first stage of the spectrometer.The output of the Mach-Zehnder interferometers are further dispersed by the second stage structure,which can be realized either by arrayed waveguide gratings or by digital Fourier transform spectrometer structure.We further implemented the thermo-optic modulation for the arrayed waveguide gratings to achieve a higher spectral resolution.The output channel wavelengths of the spectrometer are modulated by the embedded heater to obtain the first order derivative spectra of the input optical signal to obtain a 2nm resolution.With respect to the computer simulation and device characterization results,the 400nm spectral range and the nanoscale resolution have been demonstrated.展开更多
Non-orthogonal multiple access(NOMA)represents the latest addition to the array of multiple access techniques,enabling simultaneous servicing of multiple users within a singular resource block in terms of time,frequen...Non-orthogonal multiple access(NOMA)represents the latest addition to the array of multiple access techniques,enabling simultaneous servicing of multiple users within a singular resource block in terms of time,frequency,and code.A typical NOMA configuration comprises a base station along with proximate and distant users.The proximity users experience more favorable channel conditions in contrast to distant users,resulting in a compromised performance for the latter due to the less favorable channel conditions.When cooperative communication is integrated with NOMA,the overall system performance,including spectral efficiency and capacity,is further elevated.This study introduces a cooperative NOMA setup in the downlink,involving three users,and employs dynamic power allocation(DPA).Within this framework,User 2 acts as a relay,functioning under the decode-and-forward protocol,forwarding signals to both User 1 and User 3.This arrangement aims to bolster the performance of the user positioned farthest from the base station,who is adversely affected by weaker channel conditions.Theoretical and simulation outcomes reveal enhancements within the system’s performance.展开更多
Due to the complexity of data,interpretation of pattern or extraction of information becomes difficult;therefore application of machine learning is used to teach machines how to handle data more efficiently.With the i...Due to the complexity of data,interpretation of pattern or extraction of information becomes difficult;therefore application of machine learning is used to teach machines how to handle data more efficiently.With the increase of datasets,various organizations now apply machine learning applications and algorithms.Many industries apply machine learning to extract relevant information for analysis purposes.Many scholars,mathematicians and programmers have carried out research and applied several machine learning approaches in order to find solution to problems.In this paper,we focus on general review of machine learning including various machine learning techniques.These techniques can be applied to different fields like image processing,data mining,predictive analysis and so on.The paper aims at reviewing machine learning techniques and algorithms.The research methodology is based on qualitative analysis where various literatures is being reviewed based on machine learning.展开更多
Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(...Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(ML)thickness,were carried out.Calculations showed that band gaps of 1.02 eV,0.98 eV and 0.5 eV,respectively,appear in the densities of electronic states when the thickness of Li,Be and Al coverings is one ML.These gaps disappear with increasing thickness of the metal layers:first in the Li-Si system(for two ML),then in the Al-Si system(for three ML)and then in the Be-Si system(for four ML).This behavior of the band gap can be explained by the passivation of the substrate surface states and the peculiarities of the electronic structure of the adsorbed metals.In common the results can be interpreted as describing the possibility of the formation of a two-dimensional silicide with semiconducting properties in Li-Si(100),Be-Si(100)and Al-Si(100)systems.展开更多
In this work,the thermal behavior of fin made of palladium material under the influences of thermal radiation and internal heat generation is investigated.The thermal model for the extended surface made of palladium a...In this work,the thermal behavior of fin made of palladium material under the influences of thermal radiation and internal heat generation is investigated.The thermal model for the extended surface made of palladium as the fin material is first developed and solved numerically using finite difference method.The influences of the thermal model parameters on the heat transfer behaviour of the extended surface are investigated.The results show that the rate of heat transfer through the fin and the thermal efficiency of the fin increase as the thermal conductivity of the fin material increases.This shows that fin is more efficient and effective for a larger value of thermal conductivity.However,the thermal conductivity of the fin with palladium material is low and constant at the value of approximately 75 W/mK in a wider temperature range of-100℃and 227℃.Also,it is shown that the thermal efficiencies of potential materials(except for stainless steel and brass)for fins decrease as the fin temperatures increase.This is because the thermal conductivities of most of the materials used for fins decreases as temperature increases.However,keeping other fin properties and the external conditions constant,the thermal efficiency of the palladium is constant as the temperature of the fin increases within the temperature range of-100℃and 227℃.And outside the given range of temperature,the thermal conductivity of the material increases which increases the efficiency of the fin.The study will assist in the selection of proper material for the fin and in the design of passive heat enhancement devices under different applications and conditions.展开更多
Copper Zinc Antimony Sulfide(CZAS)is derived from Copper Antimony Sulfide(CAS),a famatinite class of compound.In the current paper,the first step for using Copper,Zinc,Antimony and Sulfide as materials in manufacturin...Copper Zinc Antimony Sulfide(CZAS)is derived from Copper Antimony Sulfide(CAS),a famatinite class of compound.In the current paper,the first step for using Copper,Zinc,Antimony and Sulfide as materials in manufacturing synchrotronic biosensor-namely increasing the sensitivity of biosensor through creating Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor and using it instead of Copper Tin Sulfide,CTS(Cu2SnS3)for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells,is evaluated.Further,optimization of tris(2,2'-bipyridyl)ruthenium(II)(Ru(bpy)32+)concentrations and Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor as two main and effective materials in the intensity of synchrotron for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells are considered so that the highest sensitivity obtains.In this regard,various concentrations of two materials were prepared and photon emission was investigated in the absence of cancer cells.On the other hand,ccancer diagnosis requires the analysis of images and attributes as well as collecting many clinical and mammography variables.In diagnosis of cancer,it is important to determine whether a tumor is benign or malignant.The information about cancer risk prediction along with the type of tumor are crucial for patients and effective medical decision making.An ideal diagnostic system could effectively distinguish between benign and malignant cells;however,such a system has not been created yet.In this study,a model is developed to improve the prediction probability of cancer.It is necessary to have such a prediction model as the survival probability of cancer is high when patients are diagnosed at early stages.展开更多
Multi-factor Authentication(MFA)often referred to as Two-factor Authentication(2FA),which is a subset of MFA,is the practice of implementing additional security methods on top of a standard username and password...Multi-factor Authentication(MFA)often referred to as Two-factor Authentication(2FA),which is a subset of MFA,is the practice of implementing additional security methods on top of a standard username and password to help authenticate the identity of a user and increase the security of data.This chapter will investigate the problem with username and password logins,the different types of authentication,current best practice for multi-factor authentication and interpretations about how the technology will grow in the upcoming years.展开更多
This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that fol...This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.展开更多
The data and internet are highly growing which causes problems in management of the big-data.For these kinds of problems,there are many software frameworks used to increase the performance of the distributed system.Th...The data and internet are highly growing which causes problems in management of the big-data.For these kinds of problems,there are many software frameworks used to increase the performance of the distributed system.This software is used for the availability of large data storage.One of the most beneficial software frameworks used to utilize data in distributed systems is Hadoop.This paper introduces Apache Hadoop architecture,components of Hadoop,their significance in managing vast volumes of data in a distributed system.Hadoop Distributed File System enables the storage of enormous chunks of data over a distributed network.Hadoop Framework maintains fsImage and edits files,which supports the availability and integrity of data.This paper includes cases of Hadoop implementation,such as monitoring weather,processing bioinformatics.展开更多
In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is g...In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is given,the structure of the information process,and the phases,which are the basis for the evolution of the information space and the universe of human activity,are considered.展开更多
文摘In this study,we fabricate Si/SiGe core-shell Junctionless accumulation mode(JAM)FinFET devices through a rapid and novel process with four main steps,i.e.e-beam lithography definition,sputter deposition,alloy combination annealing,and chemical solution etching.The height of Si core is 30 nm and the thickness of Si/SiGe core-shell is about 2 nm.After finishing the fabrication of devices,we widely studied the electrical characteristics of poly Si/SiGe core-shell JAM FinFET transistors from a view of different Lg and Wch.A poly-Si/SiGe core-shell JAMFETs was successfully demonstrated and it also exhibits a superior subthreshold swing of 81mV/dec and high on/off ratio>10^5 when annealing for 1hr at 600℃.The thermal diffusion process condition for this study are 1hr at 600℃ and 6hr at 700℃ for comparison.The annealing condition at 700oC for 6 hours shows undesired electrical characteristics against the other.Results suggests that from over thermal budget causes a plenty of Ge to precipitate against to form SiGe thin film.Annealing JAMFETs at low temperature shows outstanding Subthreshold swing and better swing condition when compared to its counterpart i.e.at higher temperature.This new process can still fabricate a comparable performance to classical planar FinFET in driving current.
文摘The authors fulfilled calculations of the total energy and electronic states of Cd_(n)Se_(n) nanoparticle:“wurzite”,“sphalerite”and“rock-salt”types of the structure.It was shown that at n≤72 the“rock-salt”type is the most favorable energetically.However the extrapolation of the behavior of the energy per Cd-Se atomic pair shows that for n>130(corresponding to a size of about 2 nm),particles with a“wurtzite”structure can be more advantageous.Particles of the“wurtzite”and“rock-salt”types have an electronic structure with an energy gap.For particles with the“wurtzite”structure,the gap width decreases with increasing particle size:from 3.3 eV to 2.2 eV as the particle increases from 0.5 nm to 1.5 nm.For particles of the“rock-salt”type,the gap width grows slightly,remaining about 3 eV.“Sphalerite”-type particles have a metal-like electronic structure.
文摘The proliferation of cloud computing and internet of things has led to the connectivity of states and nations(developed and developing countries)worldwide in which global network provide platform for the connection.Digital forensics is a field of computer security that uses software applications and standard guidelines which support the extraction of evidences from any computer appliances which is perfectly enough for the court of law to use and make a judgment based on the comprehensiveness,authenticity and objectivity of the information obtained.Cybersecurity is of major concerned to the internet users worldwide due to the recent form of attacks,threat,viruses,intrusion among others going on every day among internet of things.However,it is noted that cybersecurity is based on confidentiality,integrity and validity of data.The aim of this work is make a systematic review on the application of machine learning algorithms to cybersecurity and cyber forensics and pave away for further research directions on the application of deep learning,computational intelligence,soft computing to cybersecurity and cyber forensics.
文摘This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.
文摘Detecting the presence of a valid signal is an important task of a telecommunication receiver.When the receiver is unable to detect the presence of a valid signal,due to noise and fading,it is referred to as an erasure.This work deals with the probability of erasure computation for orthogonal frequency division multiplexed(OFDM)signals used by multiple input multiple output(MIMO)systems.The theoretical results are validated by computer simulations.OFDM is widely used in present day wireless communication systems due to its ability to mitigate intersymbol interference(ISI)caused by frequency selective fading channels.MIMO systems offer the advantage of spatial multiplexing,resulting in increased bit-rate,which is the main requirement of the recent wireless standards like 5G and beyond.
文摘In this paper,a novel capacitor-inductor integrated structure was proposed.The dielectric material BaTiO3(BTO)and ferromagnetic material Ni0.5Zn0.5Fe2O4(NZFO)was prepared by sol-gel method.Phase composition and morphology of the thin films were characterized by XRD,SEM and AFM.The effect of annealing temperature on film crystallinity,surface morphology,dielectric properties and ferromagnetism was investigated.When the annealing temperature was 700°C,the BTO film and the NZFO film got the better dielectric properties and ferromagnetic properties.Then the BTO thin film was spin-coated on the substrate,and the NZFO thin film was in-situ sintered on the BTO thin film.The composite film possessed both ferromagnetism and dielectric properties.Finally,an inductive coil was fabricated on the BTO/NZFO composite film to produce a capacitance and inductance integrated device.
文摘This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.
文摘In this study,the impacts of internal heat generation on heat transfer enhancement of porous fin is theoretical investigated using differential transform method.The parametric studies reveal that porosity enhances the fin heat dissipating capacity but the internal heat generation decreases the heat enhancement capacity of extended surface.Also,it is established that when the internal heat parameter increases to some certain values,some negative effects are recorded where the fin stores heat rather than dissipating it.This scenario defeats the prime purpose of the cooling fin.Additionally,it is established in the present study that the limiting value of porosity parameter for thermal stability for the passive device increases as internal heat parameter increases.This shows that although the internal heat parameter can help assist higher range and value of thermal stability of the fin,it produces negative effect which greatly defeats the ultimate purpose of the fin.The results in the work will help in fin design for industrial applications where internal heat generation is involved.
文摘There’s a lot of value in data.The collection,fusion and mining of multi-source data will release the potential of data and bring into play the value of data.At the same time,due to their respective interests and risks of privacy exposure,there are obstacles in the development of multi-data fusion,and the phenomenon of“isolated data island”is common,which hinders the development of data fusion.
基金N.R.P.acknowledged NSF-PREM through NSFDMR-1826886,HBCU-UP Excellence in research NSFDMR-1900692A portion of this work was performed at the National High Magnetic Field Laboratory,which is supported by the National Science Foundation Cooperative Agreement No.DMR-1644779+1 种基金the State of Florida.This work was performed,in part,at the Center for Nanoscale Materials,a U.S.Department of Energy Office of Science User Facilitysupported by the U.S.Department of Energy,Office of Science,under Contract No.DE-AC02-06CH11357.
文摘We report intrinsic photoconductivity studies on one of the least examined layered compounds,ZrS2.Few-atomic layer ZrS2 field-effect transistors were fabricated on the Si/SiO2 substrate and photoconductivity measurements were performed using both two-and four-terminal configurations under the illumination of 532 nm laser source.We measured photocurrent as a function of the incident optical power at several source-drain(bias)voltages.We observe a significantly large photoconductivity when measured in the multiterminal(four-terminal)configuration compared to that in the two-terminal configuration.For an incident optical power of 90 nW,the estimated photosensitivity and the external quantum efficiency(EQE)measured in two-terminal configuration are 0.5 A/W and 120%,respectively,under a bias voltage of 650 mV.Under the same conditions,the four-terminal measurements result in much higher values for both the photoresponsivity(R)and EQE to 6 A/W and 1400%,respectively.This significant improvement in photoresponsivity and EQE in the four-terminal configuration may have been influenced by the reduction of contact resistance at the metal-semiconductor interface,which greatly impacts the carrier mobility of low conducting materials.This suggests that photoconductivity measurements performed through the two-terminal configuration in previous studies on ZrS2 and other 2D materials have severely underestimated the true intrinsic properties of transition metal dichalcogenides and their remarkable potential for optoelectronic applications.
基金This work was supported by the Chinese national found,through the pre-research project‘Research on the silicon integrated on-chip spectrometer’.
文摘With apparent size and weight advantages,on-chip spectrometer could be a good choice for the spectrum analysis application which has been widely used in numerous areas such as optical network performance monitoring,materials analysis and medical research.In order to realize the broadband and the high resolution simultaneously,we propose a new on-chip spectrometer structure,which is a two-stage structure.The coarse wavelength division is realized by the cascaded Mach-Zehnder interferometers,which is the first stage of the spectrometer.The output of the Mach-Zehnder interferometers are further dispersed by the second stage structure,which can be realized either by arrayed waveguide gratings or by digital Fourier transform spectrometer structure.We further implemented the thermo-optic modulation for the arrayed waveguide gratings to achieve a higher spectral resolution.The output channel wavelengths of the spectrometer are modulated by the embedded heater to obtain the first order derivative spectra of the input optical signal to obtain a 2nm resolution.With respect to the computer simulation and device characterization results,the 400nm spectral range and the nanoscale resolution have been demonstrated.
文摘Non-orthogonal multiple access(NOMA)represents the latest addition to the array of multiple access techniques,enabling simultaneous servicing of multiple users within a singular resource block in terms of time,frequency,and code.A typical NOMA configuration comprises a base station along with proximate and distant users.The proximity users experience more favorable channel conditions in contrast to distant users,resulting in a compromised performance for the latter due to the less favorable channel conditions.When cooperative communication is integrated with NOMA,the overall system performance,including spectral efficiency and capacity,is further elevated.This study introduces a cooperative NOMA setup in the downlink,involving three users,and employs dynamic power allocation(DPA).Within this framework,User 2 acts as a relay,functioning under the decode-and-forward protocol,forwarding signals to both User 1 and User 3.This arrangement aims to bolster the performance of the user positioned farthest from the base station,who is adversely affected by weaker channel conditions.Theoretical and simulation outcomes reveal enhancements within the system’s performance.
文摘Due to the complexity of data,interpretation of pattern or extraction of information becomes difficult;therefore application of machine learning is used to teach machines how to handle data more efficiently.With the increase of datasets,various organizations now apply machine learning applications and algorithms.Many industries apply machine learning to extract relevant information for analysis purposes.Many scholars,mathematicians and programmers have carried out research and applied several machine learning approaches in order to find solution to problems.In this paper,we focus on general review of machine learning including various machine learning techniques.These techniques can be applied to different fields like image processing,data mining,predictive analysis and so on.The paper aims at reviewing machine learning techniques and algorithms.The research methodology is based on qualitative analysis where various literatures is being reviewed based on machine learning.
文摘Within the framework of the density functional theory and the pseudopotential method,the electronic structure calculations of the“metal-Si(100)”systems with Li,Be and Al as metal coverings of one to four monolayers(ML)thickness,were carried out.Calculations showed that band gaps of 1.02 eV,0.98 eV and 0.5 eV,respectively,appear in the densities of electronic states when the thickness of Li,Be and Al coverings is one ML.These gaps disappear with increasing thickness of the metal layers:first in the Li-Si system(for two ML),then in the Al-Si system(for three ML)and then in the Be-Si system(for four ML).This behavior of the band gap can be explained by the passivation of the substrate surface states and the peculiarities of the electronic structure of the adsorbed metals.In common the results can be interpreted as describing the possibility of the formation of a two-dimensional silicide with semiconducting properties in Li-Si(100),Be-Si(100)and Al-Si(100)systems.
文摘In this work,the thermal behavior of fin made of palladium material under the influences of thermal radiation and internal heat generation is investigated.The thermal model for the extended surface made of palladium as the fin material is first developed and solved numerically using finite difference method.The influences of the thermal model parameters on the heat transfer behaviour of the extended surface are investigated.The results show that the rate of heat transfer through the fin and the thermal efficiency of the fin increase as the thermal conductivity of the fin material increases.This shows that fin is more efficient and effective for a larger value of thermal conductivity.However,the thermal conductivity of the fin with palladium material is low and constant at the value of approximately 75 W/mK in a wider temperature range of-100℃and 227℃.Also,it is shown that the thermal efficiencies of potential materials(except for stainless steel and brass)for fins decrease as the fin temperatures increase.This is because the thermal conductivities of most of the materials used for fins decreases as temperature increases.However,keeping other fin properties and the external conditions constant,the thermal efficiency of the palladium is constant as the temperature of the fin increases within the temperature range of-100℃and 227℃.And outside the given range of temperature,the thermal conductivity of the material increases which increases the efficiency of the fin.The study will assist in the selection of proper material for the fin and in the design of passive heat enhancement devices under different applications and conditions.
文摘Copper Zinc Antimony Sulfide(CZAS)is derived from Copper Antimony Sulfide(CAS),a famatinite class of compound.In the current paper,the first step for using Copper,Zinc,Antimony and Sulfide as materials in manufacturing synchrotronic biosensor-namely increasing the sensitivity of biosensor through creating Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor and using it instead of Copper Tin Sulfide,CTS(Cu2SnS3)for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells,is evaluated.Further,optimization of tris(2,2'-bipyridyl)ruthenium(II)(Ru(bpy)32+)concentrations and Copper Zinc Antimony Sulfide,CZAS(Cu1.18Zn0.40Sb1.90S7.2)semiconductor as two main and effective materials in the intensity of synchrotron for tracking,monitoring,imaging,measuring,diagnosing and detecting cancer cells are considered so that the highest sensitivity obtains.In this regard,various concentrations of two materials were prepared and photon emission was investigated in the absence of cancer cells.On the other hand,ccancer diagnosis requires the analysis of images and attributes as well as collecting many clinical and mammography variables.In diagnosis of cancer,it is important to determine whether a tumor is benign or malignant.The information about cancer risk prediction along with the type of tumor are crucial for patients and effective medical decision making.An ideal diagnostic system could effectively distinguish between benign and malignant cells;however,such a system has not been created yet.In this study,a model is developed to improve the prediction probability of cancer.It is necessary to have such a prediction model as the survival probability of cancer is high when patients are diagnosed at early stages.
文摘Multi-factor Authentication(MFA)often referred to as Two-factor Authentication(2FA),which is a subset of MFA,is the practice of implementing additional security methods on top of a standard username and password to help authenticate the identity of a user and increase the security of data.This chapter will investigate the problem with username and password logins,the different types of authentication,current best practice for multi-factor authentication and interpretations about how the technology will grow in the upcoming years.
文摘This document provides some guidelines to authors for submission in order to work towards a seamless submission process.While complete adherence to the following guidelines is not enforced,authors should note that following through with the guidelines will be helpful in expediting the copyediting and proofreading processes,and allow for improved readability during the review process.
文摘The data and internet are highly growing which causes problems in management of the big-data.For these kinds of problems,there are many software frameworks used to increase the performance of the distributed system.This software is used for the availability of large data storage.One of the most beneficial software frameworks used to utilize data in distributed systems is Hadoop.This paper introduces Apache Hadoop architecture,components of Hadoop,their significance in managing vast volumes of data in a distributed system.Hadoop Distributed File System enables the storage of enormous chunks of data over a distributed network.Hadoop Framework maintains fsImage and edits files,which supports the availability and integrity of data.This paper includes cases of Hadoop implementation,such as monitoring weather,processing bioinformatics.
文摘In this article,the phenomenon of“information space”and its methods of study,its types,elementary structure and qualitative characteristics are discussed,the author’s definition of the concept of“information”is given,the structure of the information process,and the phases,which are the basis for the evolution of the information space and the universe of human activity,are considered.
