Patient privacy and data protection have been crucial concerns in Ehealthcare systems for many years.In modern-day applications,patient data usually holds clinical imagery,records,and other medical details.Lately,the ...Patient privacy and data protection have been crucial concerns in Ehealthcare systems for many years.In modern-day applications,patient data usually holds clinical imagery,records,and other medical details.Lately,the Internet of Medical Things(IoMT),equipped with cloud computing,has come out to be a beneficial paradigm in the healthcare field.However,the openness of networks and systems leads to security threats and illegal access.Therefore,reliable,fast,and robust security methods need to be developed to ensure the safe exchange of healthcare data generated from various image sensing and other IoMT-driven devices in the IoMT network.This paper presents an image protection scheme for healthcare applications to protect patients’medical image data exchanged in IoMT networks.The proposed security scheme depends on an enhanced 2D discrete chaotic map and allows dynamic substitution based on an optimized highly-nonlinear S-box and diffusion to gain an excellent security performance.The optimized S-box has an excellent nonlinearity score of 112.The new image protection scheme is efficient enough to exhibit correlation values less than 0.0022,entropy values higher than 7.999,and NPCR values around 99.6%.To reveal the efficacy of the scheme,several comparison studies are presented.These comparison studies reveal that the novel protection scheme is robust,efficient,and capable of securing healthcare imagery in IoMT systems.展开更多
Single or multiple S-boxes are widely used in image encryption schemes, and in many image encryption schemes the asynchronous encryption structure is utilized, which separates the processes of substitution and diffusi...Single or multiple S-boxes are widely used in image encryption schemes, and in many image encryption schemes the asynchronous encryption structure is utilized, which separates the processes of substitution and diffusion. In this paper, we analyze the defects of this structure based on the example of an article and crack it using a simpler method. To address the defects of the asynchronous encryption structure, a novel encryption scheme is proposed, in which the structure of synchronous substitution and diffusion based on double S-boxes is utilized, so the processes of substitution and diffusion are combined together and the attackers cannot crack the cryptosystem by any of the processes. The simulation results and security analysis show that the proposed encryption scheme is safer and more efficient to expediently use in the real-time system.展开更多
Nuclear Magnetic inversion is the basis of NMR Resonance （NMR） T2 logging interpretation. The regularization parameter selection of the penalty term directly influences the NMR T2 inversion result. We implemented b...Nuclear Magnetic inversion is the basis of NMR Resonance （NMR） T2 logging interpretation. The regularization parameter selection of the penalty term directly influences the NMR T2 inversion result. We implemented both norm smoothing and curvature smoothing methods for NMR T2 inversion, and compared the inversion results with respect to the optimal regular- ization parameters （（Xopt） which were selected by the dis- crepancy principle （DP）, generalized cross-validation （GCV）, S-curve, L-curve, and the slope of L-curve methods, respectively. The numerical results indicate that the DP method can lead to an oscillating or oversmoothed solution which is caused by an inaccurately estimated noise level. The （Xopt selected by the L-curve method is occa- sionally small or large which causes an undersmoothed or oversmoothed T2 distribution. The inversion results from GCV, S-curve and the slope of L-curve methods show satisfying inversion results. The slope of the L-curve method with less computation is more suitable for NMR T2 inversion. The inverted T2 distribution from norm smoothing is better than that from curvature smoothing when the noise level is high.展开更多
Being as unique nonlinear components of block ciphers,substitution boxes（S-boxes） directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes th...Being as unique nonlinear components of block ciphers,substitution boxes（S-boxes） directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion（SAC）,bits independence criterion（BIC）,differential probability（DP） and linear probability（LP）.To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm（CSABC） is designed.It uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their performance.In addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other algorithms.Simulation results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria.展开更多
The strict avalanche criterion(SAC)is one of the most important cryptographic criteria for substitution boxes(S-boxes)used in many symmetric encryption systems.However,there are few constructive methods for S-boxes fu...The strict avalanche criterion(SAC)is one of the most important cryptographic criteria for substitution boxes(S-boxes)used in many symmetric encryption systems.However,there are few constructive methods for S-boxes fulfilling the SAC until now.In this paper,to construct S-boxes satisfying the SAC directly,we generalize the concatenation techniques of Boolean functions to S-boxes.Using the idea of concatenating small variable S-boxes,we present a simple yet effective construction method of S-boxes satisfying the SAC.Finally,a simple example on how to construct SAC S-boxes with large input variables by small variables SAC S-boxes is given.展开更多
4-bit linear relations play an important role in cryptanalysis of 4-bit crypto S-boxes. 4-bit finite differences have also been a major part of cryptanalysis of 4-bit S-boxes. Existence of all 4-bit linear relations h...4-bit linear relations play an important role in cryptanalysis of 4-bit crypto S-boxes. 4-bit finite differences have also been a major part of cryptanalysis of 4-bit S-boxes. Existence of all 4-bit linear relations have been counted for all of 16 input and 16 output 4-bit bit patterns of 4-bit Crypto S-boxes said as S-boxes has been reported in Linear Cryptanalysis of 4-bit S-boxes. Count of existing finite differences from each element of output S-boxes to distant output S-boxes have been noted in Differential Cryptanalysis of S-boxes. In this paper a brief review of these two cryptanalytic methods for 4-bit S-boxes has been introduced in a very lucid and conceptual manner. Two new analysis techniques, one to search for the existing linear approximations among the input vectors (IPVs) and output Boolean functions (BFs) of a particular S-box has also been introduced in this paper. The search is limited to find the existing linear relations or approximations in the contrary to count the number of existent linear relations among all 16, 4-bit input and output bit patterns within all possible linear approximations. Another is to find number of balanced BFs in difference output S-boxes. Better the number of Balanced BFs, Better the security.展开更多
Substitution boxes (S-Boxes) in advanced encryption standard (AES) are vulnerable to attacks bypower analysis.The general S-Boxes masking schemes in circuit level need to adjust the design flow andlibrary databases.Th...Substitution boxes (S-Boxes) in advanced encryption standard (AES) are vulnerable to attacks bypower analysis.The general S-Boxes masking schemes in circuit level need to adjust the design flow andlibrary databases.The masking strategies in algorithm level view each S-Box as an independent moduleand mask them respectively,which are costly in size and power for non-linear characteristic of S-Boxes.The new method uses dynamic inhomogeneous S-Boxes instead of traditional homogeneous S-Boxes,andarranges the S-Boxes randomly.So the power and data path delay of substitution unit become unpre-dictable.The experimental results demonstrate that this scheme takes advantages of the circuit character-istics of various S-Box implementations to eliminate the correlation between crypto operation and power.Itneeds less extra circuits and suits resource constrained applications.展开更多
Fluorine atoms confer desirable biophysical,chemical,and biological properties to peptides/proteins by participating in various intermolecular interactions with their environment,but they are rarely used to control su...Fluorine atoms confer desirable biophysical,chemical,and biological properties to peptides/proteins by participating in various intermolecular interactions with their environment,but they are rarely used to control supramolecular chirality and functional.Herein,to identify the effects of fluorine substitution on the chirality and function of supramolecular assem-blies,C2-symmetric benzene-paradicarboxamide-based phenylalanine(phe)derivatives and three monofluorinated variants that had a single fluorine atom on their benzyl side chain in either the ortho,meta,or para position were synthesized.The experimental and theoretical results clearly show that the resulting assembled fibrils were supported by multiple interactions,including hydrogen bonding,π–πstacking and C/O–H…F–CAr interactions.Compared to nonfluorinated analogs,fluorine and its ring position on the aromatic side chain dictated the type and strength of the F···H interaction and then induced changes in supramolecular chirality and fiber morphology.Further studies on cell behavior showed that the order of positive interac-tion between high-order supramolecular chirality(M,P)and molecular chirality(L,D)on cell proliferation and viability is LM>DM>LP>DP.These findings provide a protocol for leveraging fluorine atoms and their positional dependence on directing chiral nanostructures with desirable handedness and creating fluorinated supramolecular hydrogels as extracellular matrix-mimetic scaffolds for cell culture and regenerative medicine.展开更多
基金funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University,through the Research Funding Program,Grant No.(FRP-1443-11).
文摘Patient privacy and data protection have been crucial concerns in Ehealthcare systems for many years.In modern-day applications,patient data usually holds clinical imagery,records,and other medical details.Lately,the Internet of Medical Things(IoMT),equipped with cloud computing,has come out to be a beneficial paradigm in the healthcare field.However,the openness of networks and systems leads to security threats and illegal access.Therefore,reliable,fast,and robust security methods need to be developed to ensure the safe exchange of healthcare data generated from various image sensing and other IoMT-driven devices in the IoMT network.This paper presents an image protection scheme for healthcare applications to protect patients’medical image data exchanged in IoMT networks.The proposed security scheme depends on an enhanced 2D discrete chaotic map and allows dynamic substitution based on an optimized highly-nonlinear S-box and diffusion to gain an excellent security performance.The optimized S-box has an excellent nonlinearity score of 112.The new image protection scheme is efficient enough to exhibit correlation values less than 0.0022,entropy values higher than 7.999,and NPCR values around 99.6%.To reveal the efficacy of the scheme,several comparison studies are presented.These comparison studies reveal that the novel protection scheme is robust,efficient,and capable of securing healthcare imagery in IoMT systems.
基金Project supported by the Natural Science Foundation of Shaanxi Province,China(Grant No.2014JM8322)
文摘Single or multiple S-boxes are widely used in image encryption schemes, and in many image encryption schemes the asynchronous encryption structure is utilized, which separates the processes of substitution and diffusion. In this paper, we analyze the defects of this structure based on the example of an article and crack it using a simpler method. To address the defects of the asynchronous encryption structure, a novel encryption scheme is proposed, in which the structure of synchronous substitution and diffusion based on double S-boxes is utilized, so the processes of substitution and diffusion are combined together and the attackers cannot crack the cryptosystem by any of the processes. The simulation results and security analysis show that the proposed encryption scheme is safer and more efficient to expediently use in the real-time system.
基金funded by Shell International Exploration and Production Inc.(PT45371)the National Natural Science Foundation of China-China National Petroleum Corporation Petrochemical Engineering United Fund(U1262114)the National Natural Science Foundation of China(41272163)
文摘Nuclear Magnetic inversion is the basis of NMR Resonance （NMR） T2 logging interpretation. The regularization parameter selection of the penalty term directly influences the NMR T2 inversion result. We implemented both norm smoothing and curvature smoothing methods for NMR T2 inversion, and compared the inversion results with respect to the optimal regular- ization parameters （（Xopt） which were selected by the dis- crepancy principle （DP）, generalized cross-validation （GCV）, S-curve, L-curve, and the slope of L-curve methods, respectively. The numerical results indicate that the DP method can lead to an oscillating or oversmoothed solution which is caused by an inaccurately estimated noise level. The （Xopt selected by the L-curve method is occa- sionally small or large which causes an undersmoothed or oversmoothed T2 distribution. The inversion results from GCV, S-curve and the slope of L-curve methods show satisfying inversion results. The slope of the L-curve method with less computation is more suitable for NMR T2 inversion. The inverted T2 distribution from norm smoothing is better than that from curvature smoothing when the noise level is high.
基金supported by the National Natural Science Foundation of China(6060309260975042)
文摘Being as unique nonlinear components of block ciphers,substitution boxes（S-boxes） directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion（SAC）,bits independence criterion（BIC）,differential probability（DP） and linear probability（LP）.To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm（CSABC） is designed.It uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their performance.In addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other algorithms.Simulation results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria.
基金Supported by the National Science Foundation of China(No.60773002,61072140)the 111 Project(No.B08038),the Doctoral Program Foundation of Institutions of Higher Education of China(No.20100203110003)+1 种基金the Fundamental Research Funds for the Central Universities(No.JY10000901034)the Anhui Provincial Natural Science Foundation(No.1208085QF119)
文摘The strict avalanche criterion(SAC)is one of the most important cryptographic criteria for substitution boxes(S-boxes)used in many symmetric encryption systems.However,there are few constructive methods for S-boxes fulfilling the SAC until now.In this paper,to construct S-boxes satisfying the SAC directly,we generalize the concatenation techniques of Boolean functions to S-boxes.Using the idea of concatenating small variable S-boxes,we present a simple yet effective construction method of S-boxes satisfying the SAC.Finally,a simple example on how to construct SAC S-boxes with large input variables by small variables SAC S-boxes is given.
文摘4-bit linear relations play an important role in cryptanalysis of 4-bit crypto S-boxes. 4-bit finite differences have also been a major part of cryptanalysis of 4-bit S-boxes. Existence of all 4-bit linear relations have been counted for all of 16 input and 16 output 4-bit bit patterns of 4-bit Crypto S-boxes said as S-boxes has been reported in Linear Cryptanalysis of 4-bit S-boxes. Count of existing finite differences from each element of output S-boxes to distant output S-boxes have been noted in Differential Cryptanalysis of S-boxes. In this paper a brief review of these two cryptanalytic methods for 4-bit S-boxes has been introduced in a very lucid and conceptual manner. Two new analysis techniques, one to search for the existing linear approximations among the input vectors (IPVs) and output Boolean functions (BFs) of a particular S-box has also been introduced in this paper. The search is limited to find the existing linear relations or approximations in the contrary to count the number of existent linear relations among all 16, 4-bit input and output bit patterns within all possible linear approximations. Another is to find number of balanced BFs in difference output S-boxes. Better the number of Balanced BFs, Better the security.
基金the National High Technology Research and Development Programme of China(No.2006AA01Z226)
文摘Substitution boxes (S-Boxes) in advanced encryption standard (AES) are vulnerable to attacks bypower analysis.The general S-Boxes masking schemes in circuit level need to adjust the design flow andlibrary databases.The masking strategies in algorithm level view each S-Box as an independent moduleand mask them respectively,which are costly in size and power for non-linear characteristic of S-Boxes.The new method uses dynamic inhomogeneous S-Boxes instead of traditional homogeneous S-Boxes,andarranges the S-Boxes randomly.So the power and data path delay of substitution unit become unpre-dictable.The experimental results demonstrate that this scheme takes advantages of the circuit character-istics of various S-Box implementations to eliminate the correlation between crypto operation and power.Itneeds less extra circuits and suits resource constrained applications.
基金supported by the National Natural Science Foundation of China(Nos.52003072,51833006)Chinese Postdoctoral Science Foundation(2021M690891)+1 种基金the GHfund B(20220202,ghfund202202021124)Key Scientific and Technological Project of Henan Province 222102310494,and Startup Fund for Young Faculty at SJTU.
文摘Fluorine atoms confer desirable biophysical,chemical,and biological properties to peptides/proteins by participating in various intermolecular interactions with their environment,but they are rarely used to control supramolecular chirality and functional.Herein,to identify the effects of fluorine substitution on the chirality and function of supramolecular assem-blies,C2-symmetric benzene-paradicarboxamide-based phenylalanine(phe)derivatives and three monofluorinated variants that had a single fluorine atom on their benzyl side chain in either the ortho,meta,or para position were synthesized.The experimental and theoretical results clearly show that the resulting assembled fibrils were supported by multiple interactions,including hydrogen bonding,π–πstacking and C/O–H…F–CAr interactions.Compared to nonfluorinated analogs,fluorine and its ring position on the aromatic side chain dictated the type and strength of the F···H interaction and then induced changes in supramolecular chirality and fiber morphology.Further studies on cell behavior showed that the order of positive interac-tion between high-order supramolecular chirality(M,P)and molecular chirality(L,D)on cell proliferation and viability is LM>DM>LP>DP.These findings provide a protocol for leveraging fluorine atoms and their positional dependence on directing chiral nanostructures with desirable handedness and creating fluorinated supramolecular hydrogels as extracellular matrix-mimetic scaffolds for cell culture and regenerative medicine.
