The in-band full-duplex(IBFD)mechanism is of interest in beyond 5 G systems due to its potential to enhance spectral efficiency and reduce delay.To achieve the maximum gain of IBFD systems,the significant self-interfe...The in-band full-duplex(IBFD)mechanism is of interest in beyond 5 G systems due to its potential to enhance spectral efficiency and reduce delay.To achieve the maximum gain of IBFD systems,the significant self-interference(SI)must be efficiently suppressed.The challenges of wideband selfinterference cancellation(SIC)lie in the radio frequency(RF)domain,where the performance will be limited by the hardware.This paper reviews current RF cancellation mechanisms and investigates an efficient mechanism for future wideband systems with minimum complexity.The working principle and implementation details of multi-tap cancellers are first introduced,then an optical domain-based RF canceller is reviewed,and a novel low-cost design is proposed.To minimize the cost and complexity of the canceller,the minimum required number of taps are analyzed.Simulation results show that with the commonly used 12-bits analog-to-digital converter(ADC)at the receiver,the novel optical domain-based canceller can enable efficient SIC in the 3 GPP LTE specifications compatible system within 400 MHz bandwidth.展开更多
Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspe...Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspectives. Existing domain-based methods to predict PPIs typically infer domain interactions from known interacting sets of proteins. However,these methods are costly and complex to implement. In this paper, a simple and effective prediction model is proposed. In this model,an improved multiinstance learning( MIL) algorithm( MilCaA) is designed that doesn't need to take the domain interactions into consideration to construct MIL bags. Then, the pseudo-amino acid composition( PseAAC) transformation method is used to encode the instances in a multi-instance bag and the principal components analysis( PCA) is also used to reduce the feature dimension. Finally, several traditional machine learning and MIL methods are used to verify the proposed model. Experimental results demonstrate that MilCaA performs better than state-of-the-art techniques including the traditional machine learning methods which are widely used in PPIs prediction.展开更多
In this work,we present a domain-based algorithm to simulate the propagation of a plane-strain hydraulic fracture in a zero-toughness permeable elastic medium.The algorithm utilizes a domain-based method to solve the ...In this work,we present a domain-based algorithm to simulate the propagation of a plane-strain hydraulic fracture in a zero-toughness permeable elastic medium.The algorithm utilizes a domain-based method to solve the elasticity equation and integrates a multi-scale tip asymptote,which is particular to hydraulic fractures,into this framework.This integration is key to accurately model the energy dissipation and the fluid leak-off in the fracture tip region.The algorithm combines a 2D finite volume method(FVM)for solving the elasticity equation with a 1D FVM for solving the nonlinear lubrication equation.Incorporating the far-field asymptotics and using a moving-mesh scheme reduces the computational burden while improving the accuracy of the scheme.The paper concludes with an analysis of the numerical results.This study demonstrates the potential of this domain-based approach for modeling hydraulic fractures in poroelastic media.展开更多
This paper describes a numerical algorithm for solving the classic problem of a plane strain(KGD)fracture propagating in an impermeable elastic medium with zero toughness.The method,which takes advantage of the self-s...This paper describes a numerical algorithm for solving the classic problem of a plane strain(KGD)fracture propagating in an impermeable elastic medium with zero toughness.The method,which takes advantage of the self-similar nature of the solution,combines a domain-based scheme to solve the elasticity equations and a finite volume method to solve the nonlinear lubrication equation.This work represents a first step towards developing a model able to account for pore pressure diffusion in the medium and corresponding poroelastic effects,noting that these processes are more efficiently solved using a domain-based rather than a boundary integral method.To enhance the efficiency and accuracy of the numerical scheme,the far-field crack asymptotics is embedded in the discretized elastic relationship between the fluid pressure and the crack opening,while the coupled fluid-solid tip asymptote is enforced in a weak form when solving the nonlinear lubrication equation.The proposed technique yields results that closely match the analytical solution,even with a coarse mesh.This approach offers potential for addressing more complex hydraulic fracturing problems in the future.展开更多
Protein evolution proceeds by two distinct processes： 1） individual mutation and selection for adaptive mutations and 2） rearrangement of entire domains within proteins into novel combinations, producing new protei...Protein evolution proceeds by two distinct processes： 1） individual mutation and selection for adaptive mutations and 2） rearrangement of entire domains within proteins into novel combinations, producing new protein families that combine functional properties in ways that previously did not exist. Domain rearrangement poses a challenge to sequence alignment-based search methods, such as BLAST, in predicting homology since the methodology implicitly assumes that related proteins primarily differ from each other by individual mutations. Moreover, there is ample evidence that the evolutionary process has used （and continues to use） domains as building blocks, therefore, it seems fit to utilize computational, domain-based methods to reconstruct that process. A challenge and opportunity for computational biology is how to use knowledge of evolutionary domain recombination to characterize families of proteins whose evolutionary history includes such recombination, to discover novel proteins, and to infer protein-protein interactions. In this paper we review techniques and databases that exploit our growing knowledge of “horizontal” protein evolution, and suggest possible areas of future development. We illustrate the power of the domain-based methods and the possible directions of future development by a case history in progress aiming at facilitating a particular approach to understanding microbial pathogenicity.展开更多
Global Navigation Satellite System precise positioning using carrier phase measurements requires reliable ambiguity resolution.It is challenging to obtain continuous precise positions with a high ambiguity fixing rate...Global Navigation Satellite System precise positioning using carrier phase measurements requires reliable ambiguity resolution.It is challenging to obtain continuous precise positions with a high ambiguity fixing rate under a wide range of dynamic scenes with a single base station,thus the positioning accuracy will be degraded seriously.The Forward-Backward Combination(FBC),a common post-processing smoothing method,is simply the weighted average of the positions of forward and backward filtering.When the ambiguity fixing rate of the one-way(forward or backward)filter is low,the FBC method usually cannot provide accurate and reliable positioning results.Consequently,this paper proposed a method to improve the accuracy of positions by integrating forward and backward AR,which combines the forward and backward ambiguities instead of positions-referred to as ambiguity domain-based integration(ADBI).The purpose of ADBI is to find a reliable correct integer ambiguities by making full use of the integer nature of ambiguities and integrating the ambiguities from the forward and backward filters.Once the integer ambiguities are determined correctly and reliably with ADBI,then the positions are updated with the fixing ambiguities constrained,in which more accurate positions with high confidence can be achieved.The effectiveness of the proposed approach is validated with airborne and car-borne dynamic experiments.The experimental results demonstrated that much better accuracy of position and higher ambiguity-fixed success rate can be achieved than the traditional post-processing method.展开更多
基金supported by the research grant from Huawei Technologies(Sweden)ABsupported by the U.K.Engineering and Physical Sciences Research Council(EPSRC)under Grant EP/P009549/1。
文摘The in-band full-duplex(IBFD)mechanism is of interest in beyond 5 G systems due to its potential to enhance spectral efficiency and reduce delay.To achieve the maximum gain of IBFD systems,the significant self-interference(SI)must be efficiently suppressed.The challenges of wideband selfinterference cancellation(SIC)lie in the radio frequency(RF)domain,where the performance will be limited by the hardware.This paper reviews current RF cancellation mechanisms and investigates an efficient mechanism for future wideband systems with minimum complexity.The working principle and implementation details of multi-tap cancellers are first introduced,then an optical domain-based RF canceller is reviewed,and a novel low-cost design is proposed.To minimize the cost and complexity of the canceller,the minimum required number of taps are analyzed.Simulation results show that with the commonly used 12-bits analog-to-digital converter(ADC)at the receiver,the novel optical domain-based canceller can enable efficient SIC in the 3 GPP LTE specifications compatible system within 400 MHz bandwidth.
基金National Natural Science Foundations of China(Nos.61503116,61402007)Foundation for Young Talents in the Colleges of Anhui Province Committee,China(No.2013SQRL097ZD)+1 种基金Natural Science Foundation of Anhui Educational Committee,China(No.KJ2014A198)Natural Science Foundation of Anhui Province,China(No.1408085QF108)
文摘Domain-based protein-protein interactions( PPIs) is a problem that has drawn the attentions of many researchers in recent years and it has been studied using lots of computational approaches from many different perspectives. Existing domain-based methods to predict PPIs typically infer domain interactions from known interacting sets of proteins. However,these methods are costly and complex to implement. In this paper, a simple and effective prediction model is proposed. In this model,an improved multiinstance learning( MIL) algorithm( MilCaA) is designed that doesn't need to take the domain interactions into consideration to construct MIL bags. Then, the pseudo-amino acid composition( PseAAC) transformation method is used to encode the instances in a multi-instance bag and the principal components analysis( PCA) is also used to reduce the feature dimension. Finally, several traditional machine learning and MIL methods are used to verify the proposed model. Experimental results demonstrate that MilCaA performs better than state-of-the-art techniques including the traditional machine learning methods which are widely used in PPIs prediction.
基金support from the Center on Geo-process in Mineral Carbon Storage,an Energy Frontier Research Center funded by the U.S.Department of Energy(DOE),Office of Science,Basic Energy Sciences(BES),under award#DE-SC0023429the National Natural Science Foundation of China under awards#42320104003 and#42077247the International Exchange Program for Graduate Students,Tongji University(NO.2023020010).
文摘In this work,we present a domain-based algorithm to simulate the propagation of a plane-strain hydraulic fracture in a zero-toughness permeable elastic medium.The algorithm utilizes a domain-based method to solve the elasticity equation and integrates a multi-scale tip asymptote,which is particular to hydraulic fractures,into this framework.This integration is key to accurately model the energy dissipation and the fluid leak-off in the fracture tip region.The algorithm combines a 2D finite volume method(FVM)for solving the elasticity equation with a 1D FVM for solving the nonlinear lubrication equation.Incorporating the far-field asymptotics and using a moving-mesh scheme reduces the computational burden while improving the accuracy of the scheme.The paper concludes with an analysis of the numerical results.This study demonstrates the potential of this domain-based approach for modeling hydraulic fractures in poroelastic media.
基金support from the International Exchange Program for Graduate Students,Tongji University(NO.2023020010).
文摘This paper describes a numerical algorithm for solving the classic problem of a plane strain(KGD)fracture propagating in an impermeable elastic medium with zero toughness.The method,which takes advantage of the self-similar nature of the solution,combines a domain-based scheme to solve the elasticity equations and a finite volume method to solve the nonlinear lubrication equation.This work represents a first step towards developing a model able to account for pore pressure diffusion in the medium and corresponding poroelastic effects,noting that these processes are more efficiently solved using a domain-based rather than a boundary integral method.To enhance the efficiency and accuracy of the numerical scheme,the far-field crack asymptotics is embedded in the discretized elastic relationship between the fluid pressure and the crack opening,while the coupled fluid-solid tip asymptote is enforced in a weak form when solving the nonlinear lubrication equation.The proposed technique yields results that closely match the analytical solution,even with a coarse mesh.This approach offers potential for addressing more complex hydraulic fracturing problems in the future.
基金supported by NSF of USA under Grant Nos. 0835718 and 0235792NIH under Grant Nos. 5PN2EY016570-06 and5R01NS063405-02+2 种基金the Beckman Institute for Advanced Science and Technologythe National Center for Supercomputing Applicationsthe Renaissance Computing Institute
文摘Protein evolution proceeds by two distinct processes： 1） individual mutation and selection for adaptive mutations and 2） rearrangement of entire domains within proteins into novel combinations, producing new protein families that combine functional properties in ways that previously did not exist. Domain rearrangement poses a challenge to sequence alignment-based search methods, such as BLAST, in predicting homology since the methodology implicitly assumes that related proteins primarily differ from each other by individual mutations. Moreover, there is ample evidence that the evolutionary process has used （and continues to use） domains as building blocks, therefore, it seems fit to utilize computational, domain-based methods to reconstruct that process. A challenge and opportunity for computational biology is how to use knowledge of evolutionary domain recombination to characterize families of proteins whose evolutionary history includes such recombination, to discover novel proteins, and to infer protein-protein interactions. In this paper we review techniques and databases that exploit our growing knowledge of “horizontal” protein evolution, and suggest possible areas of future development. We illustrate the power of the domain-based methods and the possible directions of future development by a case history in progress aiming at facilitating a particular approach to understanding microbial pathogenicity.
基金the National Science Fund for Distinguished Young Scholars(Grant No.41825009)the Funds for Creative Research Groups of China(Grant No.41721003)Changjiang Scholars program.
文摘Global Navigation Satellite System precise positioning using carrier phase measurements requires reliable ambiguity resolution.It is challenging to obtain continuous precise positions with a high ambiguity fixing rate under a wide range of dynamic scenes with a single base station,thus the positioning accuracy will be degraded seriously.The Forward-Backward Combination(FBC),a common post-processing smoothing method,is simply the weighted average of the positions of forward and backward filtering.When the ambiguity fixing rate of the one-way(forward or backward)filter is low,the FBC method usually cannot provide accurate and reliable positioning results.Consequently,this paper proposed a method to improve the accuracy of positions by integrating forward and backward AR,which combines the forward and backward ambiguities instead of positions-referred to as ambiguity domain-based integration(ADBI).The purpose of ADBI is to find a reliable correct integer ambiguities by making full use of the integer nature of ambiguities and integrating the ambiguities from the forward and backward filters.Once the integer ambiguities are determined correctly and reliably with ADBI,then the positions are updated with the fixing ambiguities constrained,in which more accurate positions with high confidence can be achieved.The effectiveness of the proposed approach is validated with airborne and car-borne dynamic experiments.The experimental results demonstrated that much better accuracy of position and higher ambiguity-fixed success rate can be achieved than the traditional post-processing method.
