With the rapid advancement in exploring perceptual interactions and digital twins,metaverse technology has emerged to transcend the constraints of space-time and reality,facilitating remote AI-based collaboration.In t...With the rapid advancement in exploring perceptual interactions and digital twins,metaverse technology has emerged to transcend the constraints of space-time and reality,facilitating remote AI-based collaboration.In this dynamic metasystem environment,frequent information exchanges necessitate robust security measures,with Authentication and Key Agreement(AKA)serving as the primary line of defense to ensure communication security.However,traditional AKA protocols fall short in meeting the low-latency requirements essential for synchronous interactions within the metaverse.To address this challenge and enable nearly latency-free interactions,a novel low-latency AKA protocol based on chaotic maps is proposed.This protocol not only ensures mutual authentication of entities within the metasystem but also generates secure session keys.The security of these session keys is rigorously validated through formal proofs,formal verification,and informal proofs.When confronted with the Dolev-Yao(DY)threat model,the session keys are formally demonstrated to be secure under the Real-or-Random(ROR)model.The proposed protocol is further validated through simulations conducted using VMware workstation compiled in HLPSL language and C language.The simulation results affirm the protocol’s effectiveness in resisting well-known attacks while achieving the desired low latency for optimal metaverse interactions.展开更多
Background: When continuous scale measurements are available, agreements between two measuring devices are assessed both graphically and analytically. In clinical investigations, Bland and Altman proposed plotting sub...Background: When continuous scale measurements are available, agreements between two measuring devices are assessed both graphically and analytically. In clinical investigations, Bland and Altman proposed plotting subject-wise differences between raters against subject-wise averages. In order to scientifically assess agreement, Bartko recommended combining the graphical approach with the statistical analytic procedure suggested by Bradley and Blackwood. The advantage of using this approach is that it enables significance testing and sample size estimation. We noted that the direct use of the results of the regression is misleading and we provide a correction in this regard. Methods: Graphical and linear models are used to assess agreements for continuous scale measurements. We demonstrate that software linear regression results should not be readily used and we provided correct analytic procedures. The degrees of freedom of the F-statistics are incorrectly reported, and we propose methods to overcome this problem by introducing the correct analytic form of the F statistic. Methods for sample size estimation using R-functions are also given. Results: We believe that the tutorial and the R-codes are useful tools for testing and estimating agreement between two rating protocols for continuous scale measurements. The interested reader may use the codes and apply them to their available data when the issue of agreement between two raters is the subject of interest.展开更多
Internet of Medical Things(IoMT)plays an essential role in collecting and managing personal medical data.In recent years,blockchain technology has put power in traditional IoMT systems for data sharing between differe...Internet of Medical Things(IoMT)plays an essential role in collecting and managing personal medical data.In recent years,blockchain technology has put power in traditional IoMT systems for data sharing between different medical institutions and improved the utilization of medical data.However,some problems in the information transfer process between wireless medical devices and mobile medical apps,such as information leakage and privacy disclosure.This paper first designs a cross-device key agreement model for blockchain-enabled IoMT.This model can establish a key agreement mechanism for secure medical data sharing.Meanwhile,a certificateless authenticated key agreement(KA)protocol has been proposed to strengthen the information transfer security in the cross-device key agreement model.The proposed KA protocol only requires one exchange of messages between the two parties,which can improve the protocol execution efficiency.Then,any unauthorized tampering of the transmitted signed message sent by the sender can be detected by the receiver,so this can guarantee the success of the establishment of a session key between the strange entities.The blockchain ledger can ensure that the medical data cannot be tampered with,and the certificateless mechanism can weaken the key escrow problem.Moreover,the security proof and performance analysis are given,which show that the proposed model and KA protocol are more secure and efficient than other schemes in similar literature.展开更多
With the exponential growth of intelligent Internet of Things(IoT)applications,Cloud-Edge(CE)paradigm is emerging as a solution that facilitates resource-efficient and timely services.However,it remains an underlying ...With the exponential growth of intelligent Internet of Things(IoT)applications,Cloud-Edge(CE)paradigm is emerging as a solution that facilitates resource-efficient and timely services.However,it remains an underlying issue that frequent end-edgecloud communication is over a public or adversarycontrolled channel.Additionally,with the presence of resource-constrained devices,it’s imperative to conduct the secure communication mechanism,while still guaranteeing efficiency.Physical unclonable functions(PUF)emerge as promising lightweight security primitives.Thus,we first construct a PUF-based security mechanism for vulnerable IoT devices.Further,a provably secure and PUF-based authentication key agreement scheme is proposed for establishing the secure channel in end-edge-cloud empowered IoT,without requiring pre-loaded master keys.The security of our scheme is rigorously proven through formal security analysis under the random oracle model,and security verification using AVISPA tool.The comprehensive security features are also elaborated.Moreover,the numerical results demonstrate that the proposed scheme outperforms existing related schemes in terms of computational and communication efficiency.展开更多
In order to make the quantum key agreement process immune to participant attacks, it is necessary to introduce the authentication in the communication process. A quantum key agreement protocol with identity authentica...In order to make the quantum key agreement process immune to participant attacks, it is necessary to introduce the authentication in the communication process. A quantum key agreement protocol with identity authentication that exploits the measurement correlation of six-particle entangled states is proposed. In contrast to some recently proposed quantum key agreement protocols with authentication, this protocol requires neither a semi-trusted third party nor additional private keys in the authentication process. The entire process of authentication and key agreement can be achieved using only n six-particle entangled states, which saves communication costs and reduces the complexity of the authentication process.Finally, security analysis shows that this scheme is resistant to some important attacks.展开更多
As representatives of emerging economies,BRICS countries are increasingly prominent in global governance.The rapid economic development of BRICS countries is accompanied by a significant increase in greenhouse gas(GHG...As representatives of emerging economies,BRICS countries are increasingly prominent in global governance.The rapid economic development of BRICS countries is accompanied by a significant increase in greenhouse gas(GHG)emissions,and BRICS countries are paying increasing attention to climate change issues and actively participating in the construction of the international climate regime.The Paris Agreement was a historic breakthrough in international climate negotiations,and since then BRICS countries have strengthened multilateral and bilateral cooperation in energy efficiency,agricultural emission reduction and climate governance financing.Due to the constraints of technology,cooperation mechanism construction,financing,and other objective conditions,BRICS countries still face some challenges to further advance the global climate governance agenda with their group power in the short term.Whether BRICS countries can further advance the global climate governance agenda as a group in the post-Paris Agreement era depends on whether they can improve energy efficiency and optimize their energy mix,and whether they can deepen cooperation in agricultural emission reduction and climate finance.BRICS countries need to continue to promote clean energy development and low-carbon economic transformation,deepen the potential of climate cooperation in agricultural emission reduction,and give full play to the climate financing role of the New Development Bank,so as to further enhance the level of climate cooperation.At the same time,BRICS countries can widely involve developing countries in climate governance cooperation and strengthen dialogue and exchanges with other countries,so as to promote global climate governance in the post-Paris Agreement era.展开更多
At present,the biggest obstacle that growing enterprises may encounter in their development process is insufficient funds.Private equity financing does not only solve the capital problem of enterprises,but also provid...At present,the biggest obstacle that growing enterprises may encounter in their development process is insufficient funds.Private equity financing does not only solve the capital problem of enterprises,but also provide enterprises with professional management concepts and even help growing enterprises to go public in advance.However,high returns must be accompanied by high risks.For example,private equity financing has information asymmetry risks,principal-agent risks,etc.,and these risks make it impossible to maximize the advantages of private equity financing.Therefore,in order to reduce the risks brought by financing,investment and financing parties should choose to sign gambling contracts to reduce the risk.In recent years,the use of VAM agreements has become more in China.However,according to incomplete statistics,less than 30%of VAM agreements are successful,and this result is mainly due to the insufficient depth and breadth of research on VAM agreements.Therefore,this article will comprehensively analyze the problems that need to be paid attention to when signing a gambling agreement by introducing the case of Anda Technology,and the issue of targeted risk prevention will also be discussed in this paper.展开更多
AIM:To evaluate the repeatability of central corneal thickness(CCT) measurement by entacam,and agreement of CCT measured by Pentacam and ultrasound pachymetry(USP) in Chinese myopia.Thereby investigate the possibility...AIM:To evaluate the repeatability of central corneal thickness(CCT) measurement by entacam,and agreement of CCT measured by Pentacam and ultrasound pachymetry(USP) in Chinese myopia.Thereby investigate the possibility of Pentacam as a substitute for USP in CCT measurement before refractive surgery.The effects of corneal curvature measured by Pentacam on CCT were also evaluated.· METHODS:One hundred and forty-eight right eyes of 148 individual with myopia were included in this study.Three successive Pentacam CCT measurements followed by 10 successive ultrasound pachymetry were carried out in the 148 eyes.Mean of CCT taken by each device was calculated for comparison.According to the CCT measured by USP,all the 148 eyes were divided into 3 groups:<520μm,520-560μm,>560μm.For all eyes and each group the CCT obtained by Pentacam and USP were compared.Anterior corneal curvature of the 148 eyes was also adopted for correlation analysis with CCT obtained by ultrasound pachymetry.In addition,CCT measurement using 60 random selected Scheimpflug images was performed by 3 skilled investigators at different time,and this was repeated for 3 times by a forth investigator to assess repeatability of Pentacam CCT measurement using Scheimpflug images.· RESULTS:Intraclass correlation coefficient(ICC) analysis revealed high intraobserver repeatability(ICC=0.994,F = 158.60,P <0.001) for CCT measurement by Pentacam.The interobserver(ICC=0.998,F =494.73,P <0.001) and intraobserver(ICC=0.997,F=383.98,P <0.001) repeatability for Pentacam CCT measurements using Scheimpflug images were also excellent.There was high positive correlation between the CCT values measured by Pentacam and ultrasound pachymetry(r =0.963,P <0.001).Bland-altman plots showed that the Pentacam underestimate the CCT by 8.02μm compared with ultrasouond pachymetry.The differences between Pentacam and USP increased as the CCT readings by USP increased(Pentacam vs USP:slope=-0.04,P < 0.05).The 95% upper and lower limits of agreement between CCT values obtained from the two devices were +9.33μm and-25.37μm.No significant association could be found between CCT and anterior corneal curvature.· CONCLUSION:Inter-and intraobserver variability for CCT measurements by Pentacam was considerably below clinically significant levels.CCT of myopia obtained by Scheimpflug camera,Pentacam,were highly correlated to that by ultrasound pachymetry.However,the values obtained are not directly interchangeable between Pentacam and ultrasound pachymetry as the 95% limits of agreement are relatively wide.Pentacam can be a useful instrument for measuring CCT in candidates to refractive surgery in clinic.展开更多
The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused ...The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance.展开更多
There are various challenges that are faced in group communication, so it is necessary to ensure session key. Key agreement is the fundamental cryptographic primitive for establishing a secure communication. It is a p...There are various challenges that are faced in group communication, so it is necessary to ensure session key. Key agreement is the fundamental cryptographic primitive for establishing a secure communication. It is a process of computing a shared secret contributed by two or more entities such that no single node can predetermine the resulting value. An authenticated key agreement is attained by combining the key agreement protocol with digital signatures. After a brief introduction to existing key agreement in group communication, Making use of the additive-multiplicative homomorphism in the integer ring defined by Sander and Tschudin: A new protocols, called the homomorphism key agreement, was designed, which can be self-contributory, robust, scalable and applicable in group communication.展开更多
Based on the Computable General Equilibrium (CGE) model and scenario analysis, the impacts of the U.S. withdrawal from the Paris Agreement on the carbon emission space and mitigation cost in China, European Union (EU)...Based on the Computable General Equilibrium (CGE) model and scenario analysis, the impacts of the U.S. withdrawal from the Paris Agreement on the carbon emission space and mitigation cost in China, European Union (EU), and Japan are assessed under Nationally Determined Contributions (NDCs) and 2 C scenarios due to the changed emission pathway of the U.S. The results show that, under the condition of constant global cumulative carbon emissions and a fixed burden-sharing scheme among countries, the failure of the U.S. to honor its NDC commitment to different degrees will increase the U.S. carbon emission space and decrease its mitigation cost. However, the carbon emission space of other parties, including China, EU, and Japan, will be reduced and their mitigation costs will be increased. In 2030, under the 2 C target, the carbon price will increase by 4.4e14.6 US$ t1 in China, by 9.7e35.4 US$ t1 in the EU, and by 16.0e53.5 US$ t1 in Japan. In addition, China, EU, and Japan will incur additional Gross Domestic Production (GDP) loss. Under the 2 C target, the GDP loss of China would increase by US$22.0e71.1 billion (equivalent to 16.4e53.1 US$ per capita), the EU's GDP loss would increase by US$9.4e32.1 billion (equivalent to 20.7e71.1 US$ per capita), and Japan's GDP loss will increase by US$4.1e13.5 billion (equivalent to 34.3e111.6 US$ per capita).展开更多
AIM: To evaluate the intra-operator repeatability of time domain and swept-source Fourier domain anterior segment optical coherence tomography(AS-OCT), namely, Visante ASOCT and Casia SS-1000 OCT, in measuring the pre...AIM: To evaluate the intra-operator repeatability of time domain and swept-source Fourier domain anterior segment optical coherence tomography(AS-OCT), namely, Visante ASOCT and Casia SS-1000 OCT, in measuring the preoperative parameters of implantable collamer lens(ICL) in myopic eyes, as well as the agreement between the two devices.METHODS: A total of 97 eyes from 49 myopes were investigated in this prospective case series study. The anterior chamber depth(ACD), angle-to-angle distance(ATA), pupil diameter(PD) and crystalline lens rise(CLR) in all subjects were measured for three times during one session by the same operator. The repeatability was evaluated using the within-subject standard deviation(Sw), repeatability limits and intraclass correlation coefficients(ICC). The agreement between the two systems was evaluated using the Bland-Altman plots and 95% limits of agreement(Lo A).RESULTS: The repeatability limits of Visante AS-OCT in measuring ACD, ATA, PD and CLR were 0.099, 0.141, 0.304, and 0.079 mm, respectively. The repeatability limits of Casia SS-1000 OCT in measuring ACD, ATA, PD, and CLR were 0.105, 0.127, 0.357, and 0.082 mm, respectively. Excellent repeatability could be attained in both devices, with the ICC>0.8 for all the measured variables. The interdevice agreement was excellent(P>0.05) for ACD and ATA, but poor(P<0.05) for PD and CLR.CONCLUSION: Good repeatability can be attained by time domain and swept-source Fourier-domain OCT for all the measured variables. Moreover, interdevice agreement analysis suggests that interchangeable measurements between two devices can be achieved for ACD and ATA, but not for PD and CLR;but the differences in measurements were not clinically significant.展开更多
A new efficient two-party semi-quantum key agreement protocol is proposed with high-dimensional single-particle states.Different from the previous semi-quantum key agreement protocols based on the two-level quantum sy...A new efficient two-party semi-quantum key agreement protocol is proposed with high-dimensional single-particle states.Different from the previous semi-quantum key agreement protocols based on the two-level quantum system,the propounded protocol makes use of the advantage of the high-dimensional quantum system,which possesses higher efficiency and better robustness against eavesdropping.Besides,the protocol allows the classical participant to encode the secret key with qudit shifting operations without involving any quantum measurement abilities.The designed semi-quantum key agreement protocol could resist both participant attacks and outsider attacks.Meanwhile,the conjoint analysis of security and efficiency provides an appropriate choice for reference on the dimension of single-particle states and the number of decoy states.展开更多
AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus.METHODS: Stereoacuity was measured in two different...AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus.METHODS: Stereoacuity was measured in two different sessions separated by a time interval of at least 24 h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular vision.RESULTS: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability(COR): ±13 and±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was noted.In the subjects with abnormal binocular vision, best repeatability was shown by the Frisby(COR: ±69s arc)and Randot(COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other tests.CONCLUSION:Therepeatabilityofstereoacuitymeasures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.展开更多
BACKGROUND Hepatocellular carcinoma is the most common primary liver malignancy.From the results of previous studies,Liver Imaging Reporting and Data System(LIRADS)on contrast-enhanced ultrasound(CEUS)has shown satisf...BACKGROUND Hepatocellular carcinoma is the most common primary liver malignancy.From the results of previous studies,Liver Imaging Reporting and Data System(LIRADS)on contrast-enhanced ultrasound(CEUS)has shown satisfactory diagnostic value.However,a unified conclusion on the interobserver stability of this innovative ultrasound imaging has not been determined.The present metaanalysis examined the interobserver agreement of CEUS LI-RADS to provide some reference for subsequent related research.AIM To evaluate the interobserver agreement of LI-RADS on CEUS and analyze the sources of heterogeneity between studies.METHODS Relevant papers on the subject of interobserver agreement on CEUS LI-RADS published before March 1,2020 in China and other countries were analyzed.The studies were filtered,and the diagnostic criteria were evaluated.The selected references were analyzed using the“meta”and“metafor”packages of R software version 3.6.2.RESULTS Eight studies were ultimately included in the present analysis.Meta-analysis results revealed that the summary Kappa value of included studies was 0.76[95%confidence interval,0.67-0.83],which shows substantial agreement.Higgins I2 statistics also confirmed the substantial heterogeneity(I2=91.30%,95%confidence interval,85.3%-94.9%,P<0.01).Meta-regression identified the variables,including the method of patient enrollment,method of consistency testing,and patient race,which explained the substantial study heterogeneity.CONCLUSION CEUS LI-RADS demonstrated overall substantial interobserver agreement,but heterogeneous results between studies were also obvious.Further clinical investigations should consider a modified recommendation about the experimental design.展开更多
BACKGROUND Data regarding the agreement among multiple operators for measurement of quadriceps muscle thickness by bedside ultrasonography(USG)are sparse.AIM To statistically assess the agreement among 5 operators for...BACKGROUND Data regarding the agreement among multiple operators for measurement of quadriceps muscle thickness by bedside ultrasonography(USG)are sparse.AIM To statistically assess the agreement among 5 operators for measurement of quadriceps muscle thickness on bedside USG.METHODS This was a cross-sectional observational study.The 5 operators of varied experience(comprised of 1 critical care consultant,2 fellows,and 2 nurses)independently measured quadriceps muscle thickness in triplicate for 45 critically ill patients each,using USG.Intra-and interrater agreement rates among the 5 operators were assessed using intraclass correlation coefficient(ICC)and expressed with 95%confidence interval(CI).RESULTS The 5 operators produced a total of 135 readings and 675 observations for ICC calculations to determine the intraoperator and interoperator variations respectively.For intraoperator agreement,the overall ICC(95%CI)was 0.998(0.997,0.999)for operator 1,0.998(0.997,0.999)for operator 2,0.997(0.995,0.999)for operator 3,0.999(0.998,0.999)for operator 4,and 0.998(0.997,0.999)for operator 5.For interoperator agreement,the overall ICC(95%CI)was 0.977(0.965,0.986;P<0.001)for reading 1,0.974(0.960,0.984;P<0.001)for reading 2,and 0.975(0.961,0.985;P<0.001)for reading 3.CONCLUSION USG measurement of quadriceps muscle thickness was not dependent on clinical experience,supporting training for nurses in it.展开更多
As the third legally-binding instrument of the Arctic Council, the Agreement on Enhancing International Arctic Scientific Cooperation was signed in May 2017 and entered into force on 23 May 2018. The Agreement not onl...As the third legally-binding instrument of the Arctic Council, the Agreement on Enhancing International Arctic Scientific Cooperation was signed in May 2017 and entered into force on 23 May 2018. The Agreement not only reduces obstacles to the international scientific cooperation and promotes the movement of people and equipment across borders for the effective and efficient development of Arctic scientific knowledge, but also provides an improved international Arctic legal environment for conducting Arctic scientific cooperation based on UNCLOS and institutional arrangements. However, the observer states, the NGOs and IGOs, as well as Permanent Participants are rarely mentioned in this Agreement. This article chooses one group, non-Arctic states, as a case in point in order to critically discuss the influence of this new Arctic scientific cooperation agreement. It argues that the non-Arctic states are left behind at the original legal situation and trapped in an inferior status in Arctic science. Under these circumstances, this article suggests that non-Arctic states, especially those with competitive research abilities, should appeal for amendment of the Agreement to allow wider access to research areas and data sharing, especially when cooperating with the eight-member states of the Arctic Council. Also, non-Arctic states should take the Agreement as the reference when signing bilateral agreements with Arctic states so as to safeguard their interests when conducting Arctic scientific activities. Moreover, the active participation in other fora as well as various bilateral scientific projects can assist non-Arctic states to strengthen the relations with the Arctic states and build trust in the Arctic Council.展开更多
Article 6 of the Paris Agreement introduces two international carbon markets that receive extensive attention and are expected to play an important role in the post-2020 climate regime.Three key elements of the two in...Article 6 of the Paris Agreement introduces two international carbon markets that receive extensive attention and are expected to play an important role in the post-2020 climate regime.Three key elements of the two international carbon markets,including the scope,the types of tradable units and the governance,are identified,as the basis to clarify their basic forms.Based on the key issues and their different designs identified in negotiations,this study analyzes the contributions and challenges for China to participate in international carbon markets.Considering the inherent needs of climate change mitigation,climate finance,the development of a green"Belt and Road"and the China South-South cooperation in climate change,along with the existing domestic capacities on market mechanisms,this study puts forward the short-,medium-and long-term development prospects of the two international carbon markets.展开更多
Multi-server authenticated key agreement schemes have attracted great attention to both academia and industry in recent years.However,traditional authenticated key agreement schemes in the single-server environment ar...Multi-server authenticated key agreement schemes have attracted great attention to both academia and industry in recent years.However,traditional authenticated key agreement schemes in the single-server environment are not suitable for the multi-server environment because the user has to register on each server when he/she wishes to log in various servers for different service.Moreover,it is unreasonable to consider all servers are trusted since the server in a multi-server environment may be a semi-trusted party.In order to overcome these difficulties,we designed a secure three-factor multi-server authenticated key agreement protocol based on elliptic curve cryptography,which needs the user to register only once at the registration center in order to access all semi-trusted servers.The proposed scheme can not only against various known attacks but also provides high computational efficiency.Besides,we have proved our scheme fulfills mutual authentication by using the authentication test method.展开更多
During the past decade,rapid advances in wireless communication technologies have made it possible for users to access desired services using hand-held devices.Service providers have hosted multiple servers to ensure ...During the past decade,rapid advances in wireless communication technologies have made it possible for users to access desired services using hand-held devices.Service providers have hosted multiple servers to ensure seamless online services to end-users.To ensure the security of this online communication,researchers have proposed several multi-server authentication schemes incorporating various cryptographic primitives.Due to the low power and computational capacities of mobile devices,the hash-based multi-server authenticated key agreement schemes with offline Registration Server(RS)are the most efficient choice.Recently,Kumar-Om presented such a scheme and proved its security against all renowned attacks.However,we find that their scheme bears an incorrect login phase,and is unsafe to the trace attack,the Session-Specific Temporary Information Attack(SSTIA),and the Key Compromise Impersonation Attack(KCIA).In fact,all of the existing multi-server authentication schemes(hash-based with offline RS)do not withstand KCLA.To deal with this situation,we propose an improved hash-based multi-server authentication scheme(with offline RS).We analyze the security of the proposed scheme under the random oracle model and use the t4Automated Validation of Internet Security Protocols and Applications''(AVISPA)tool.The comparative analysis of communication overhead and computational complexity metrics shows the efficiency of the proposed scheme.展开更多
基金This work has received funding from National Natural Science Foundation of China(No.42275157).
文摘With the rapid advancement in exploring perceptual interactions and digital twins,metaverse technology has emerged to transcend the constraints of space-time and reality,facilitating remote AI-based collaboration.In this dynamic metasystem environment,frequent information exchanges necessitate robust security measures,with Authentication and Key Agreement(AKA)serving as the primary line of defense to ensure communication security.However,traditional AKA protocols fall short in meeting the low-latency requirements essential for synchronous interactions within the metaverse.To address this challenge and enable nearly latency-free interactions,a novel low-latency AKA protocol based on chaotic maps is proposed.This protocol not only ensures mutual authentication of entities within the metasystem but also generates secure session keys.The security of these session keys is rigorously validated through formal proofs,formal verification,and informal proofs.When confronted with the Dolev-Yao(DY)threat model,the session keys are formally demonstrated to be secure under the Real-or-Random(ROR)model.The proposed protocol is further validated through simulations conducted using VMware workstation compiled in HLPSL language and C language.The simulation results affirm the protocol’s effectiveness in resisting well-known attacks while achieving the desired low latency for optimal metaverse interactions.
文摘Background: When continuous scale measurements are available, agreements between two measuring devices are assessed both graphically and analytically. In clinical investigations, Bland and Altman proposed plotting subject-wise differences between raters against subject-wise averages. In order to scientifically assess agreement, Bartko recommended combining the graphical approach with the statistical analytic procedure suggested by Bradley and Blackwood. The advantage of using this approach is that it enables significance testing and sample size estimation. We noted that the direct use of the results of the regression is misleading and we provide a correction in this regard. Methods: Graphical and linear models are used to assess agreements for continuous scale measurements. We demonstrate that software linear regression results should not be readily used and we provided correct analytic procedures. The degrees of freedom of the F-statistics are incorrectly reported, and we propose methods to overcome this problem by introducing the correct analytic form of the F statistic. Methods for sample size estimation using R-functions are also given. Results: We believe that the tutorial and the R-codes are useful tools for testing and estimating agreement between two rating protocols for continuous scale measurements. The interested reader may use the codes and apply them to their available data when the issue of agreement between two raters is the subject of interest.
基金supported by the National Natural Science Foundation of China under Grant 92046001,61962009,the JSPS KAKENHI Grant Numbers JP19K20250,JP20H04174,JP22K11989Leading Initiative for Excellent Young Researchers (LEADER),MEXT,Japan,and JST,PRESTO Grant Number JPMJPR21P3+1 种基金Japan.Mianxiong Dong is the corresponding author,the Doctor Scientific Research Fund of Zhengzhou University of Light Industry under Grant 2021BSJJ033Key Scientific Research Project of Colleges and Universities in Henan Province (CN)under Grant No.22A413010.
文摘Internet of Medical Things(IoMT)plays an essential role in collecting and managing personal medical data.In recent years,blockchain technology has put power in traditional IoMT systems for data sharing between different medical institutions and improved the utilization of medical data.However,some problems in the information transfer process between wireless medical devices and mobile medical apps,such as information leakage and privacy disclosure.This paper first designs a cross-device key agreement model for blockchain-enabled IoMT.This model can establish a key agreement mechanism for secure medical data sharing.Meanwhile,a certificateless authenticated key agreement(KA)protocol has been proposed to strengthen the information transfer security in the cross-device key agreement model.The proposed KA protocol only requires one exchange of messages between the two parties,which can improve the protocol execution efficiency.Then,any unauthorized tampering of the transmitted signed message sent by the sender can be detected by the receiver,so this can guarantee the success of the establishment of a session key between the strange entities.The blockchain ledger can ensure that the medical data cannot be tampered with,and the certificateless mechanism can weaken the key escrow problem.Moreover,the security proof and performance analysis are given,which show that the proposed model and KA protocol are more secure and efficient than other schemes in similar literature.
基金supported by the National Key Research and Development Program of China,“Joint Research of IoT Security System and Key Technologies Based on Quantum Key,”under project number 2020YFE0200600.
文摘With the exponential growth of intelligent Internet of Things(IoT)applications,Cloud-Edge(CE)paradigm is emerging as a solution that facilitates resource-efficient and timely services.However,it remains an underlying issue that frequent end-edgecloud communication is over a public or adversarycontrolled channel.Additionally,with the presence of resource-constrained devices,it’s imperative to conduct the secure communication mechanism,while still guaranteeing efficiency.Physical unclonable functions(PUF)emerge as promising lightweight security primitives.Thus,we first construct a PUF-based security mechanism for vulnerable IoT devices.Further,a provably secure and PUF-based authentication key agreement scheme is proposed for establishing the secure channel in end-edge-cloud empowered IoT,without requiring pre-loaded master keys.The security of our scheme is rigorously proven through formal security analysis under the random oracle model,and security verification using AVISPA tool.The comprehensive security features are also elaborated.Moreover,the numerical results demonstrate that the proposed scheme outperforms existing related schemes in terms of computational and communication efficiency.
基金the National Science Foundation of Sichuan Province, China (Grant No. 2022NSFSC0534)Major Science, and Techonolgy Application Demonstration Project in Chengdu (Grant No. 2021-YF09-0116-GX)。
文摘In order to make the quantum key agreement process immune to participant attacks, it is necessary to introduce the authentication in the communication process. A quantum key agreement protocol with identity authentication that exploits the measurement correlation of six-particle entangled states is proposed. In contrast to some recently proposed quantum key agreement protocols with authentication, this protocol requires neither a semi-trusted third party nor additional private keys in the authentication process. The entire process of authentication and key agreement can be achieved using only n six-particle entangled states, which saves communication costs and reduces the complexity of the authentication process.Finally, security analysis shows that this scheme is resistant to some important attacks.
文摘As representatives of emerging economies,BRICS countries are increasingly prominent in global governance.The rapid economic development of BRICS countries is accompanied by a significant increase in greenhouse gas(GHG)emissions,and BRICS countries are paying increasing attention to climate change issues and actively participating in the construction of the international climate regime.The Paris Agreement was a historic breakthrough in international climate negotiations,and since then BRICS countries have strengthened multilateral and bilateral cooperation in energy efficiency,agricultural emission reduction and climate governance financing.Due to the constraints of technology,cooperation mechanism construction,financing,and other objective conditions,BRICS countries still face some challenges to further advance the global climate governance agenda with their group power in the short term.Whether BRICS countries can further advance the global climate governance agenda as a group in the post-Paris Agreement era depends on whether they can improve energy efficiency and optimize their energy mix,and whether they can deepen cooperation in agricultural emission reduction and climate finance.BRICS countries need to continue to promote clean energy development and low-carbon economic transformation,deepen the potential of climate cooperation in agricultural emission reduction,and give full play to the climate financing role of the New Development Bank,so as to further enhance the level of climate cooperation.At the same time,BRICS countries can widely involve developing countries in climate governance cooperation and strengthen dialogue and exchanges with other countries,so as to promote global climate governance in the post-Paris Agreement era.
文摘At present,the biggest obstacle that growing enterprises may encounter in their development process is insufficient funds.Private equity financing does not only solve the capital problem of enterprises,but also provide enterprises with professional management concepts and even help growing enterprises to go public in advance.However,high returns must be accompanied by high risks.For example,private equity financing has information asymmetry risks,principal-agent risks,etc.,and these risks make it impossible to maximize the advantages of private equity financing.Therefore,in order to reduce the risks brought by financing,investment and financing parties should choose to sign gambling contracts to reduce the risk.In recent years,the use of VAM agreements has become more in China.However,according to incomplete statistics,less than 30%of VAM agreements are successful,and this result is mainly due to the insufficient depth and breadth of research on VAM agreements.Therefore,this article will comprehensively analyze the problems that need to be paid attention to when signing a gambling agreement by introducing the case of Anda Technology,and the issue of targeted risk prevention will also be discussed in this paper.
文摘AIM:To evaluate the repeatability of central corneal thickness(CCT) measurement by entacam,and agreement of CCT measured by Pentacam and ultrasound pachymetry(USP) in Chinese myopia.Thereby investigate the possibility of Pentacam as a substitute for USP in CCT measurement before refractive surgery.The effects of corneal curvature measured by Pentacam on CCT were also evaluated.· METHODS:One hundred and forty-eight right eyes of 148 individual with myopia were included in this study.Three successive Pentacam CCT measurements followed by 10 successive ultrasound pachymetry were carried out in the 148 eyes.Mean of CCT taken by each device was calculated for comparison.According to the CCT measured by USP,all the 148 eyes were divided into 3 groups:<520μm,520-560μm,>560μm.For all eyes and each group the CCT obtained by Pentacam and USP were compared.Anterior corneal curvature of the 148 eyes was also adopted for correlation analysis with CCT obtained by ultrasound pachymetry.In addition,CCT measurement using 60 random selected Scheimpflug images was performed by 3 skilled investigators at different time,and this was repeated for 3 times by a forth investigator to assess repeatability of Pentacam CCT measurement using Scheimpflug images.· RESULTS:Intraclass correlation coefficient(ICC) analysis revealed high intraobserver repeatability(ICC=0.994,F = 158.60,P <0.001) for CCT measurement by Pentacam.The interobserver(ICC=0.998,F =494.73,P <0.001) and intraobserver(ICC=0.997,F=383.98,P <0.001) repeatability for Pentacam CCT measurements using Scheimpflug images were also excellent.There was high positive correlation between the CCT values measured by Pentacam and ultrasound pachymetry(r =0.963,P <0.001).Bland-altman plots showed that the Pentacam underestimate the CCT by 8.02μm compared with ultrasouond pachymetry.The differences between Pentacam and USP increased as the CCT readings by USP increased(Pentacam vs USP:slope=-0.04,P < 0.05).The 95% upper and lower limits of agreement between CCT values obtained from the two devices were +9.33μm and-25.37μm.No significant association could be found between CCT and anterior corneal curvature.· CONCLUSION:Inter-and intraobserver variability for CCT measurements by Pentacam was considerably below clinically significant levels.CCT of myopia obtained by Scheimpflug camera,Pentacam,were highly correlated to that by ultrasound pachymetry.However,the values obtained are not directly interchangeable between Pentacam and ultrasound pachymetry as the 95% limits of agreement are relatively wide.Pentacam can be a useful instrument for measuring CCT in candidates to refractive surgery in clinic.
文摘The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance.
基金National Natural Science Foundation of China(No.90104005)
文摘There are various challenges that are faced in group communication, so it is necessary to ensure session key. Key agreement is the fundamental cryptographic primitive for establishing a secure communication. It is a process of computing a shared secret contributed by two or more entities such that no single node can predetermine the resulting value. An authenticated key agreement is attained by combining the key agreement protocol with digital signatures. After a brief introduction to existing key agreement in group communication, Making use of the additive-multiplicative homomorphism in the integer ring defined by Sander and Tschudin: A new protocols, called the homomorphism key agreement, was designed, which can be self-contributory, robust, scalable and applicable in group communication.
基金This study was supported by the 2017 National Natural Science Foundation Project “The Impacts of U.S. Withdrawal from Paris Agreement on Global Climate Governance and China's Response”.
文摘Based on the Computable General Equilibrium (CGE) model and scenario analysis, the impacts of the U.S. withdrawal from the Paris Agreement on the carbon emission space and mitigation cost in China, European Union (EU), and Japan are assessed under Nationally Determined Contributions (NDCs) and 2 C scenarios due to the changed emission pathway of the U.S. The results show that, under the condition of constant global cumulative carbon emissions and a fixed burden-sharing scheme among countries, the failure of the U.S. to honor its NDC commitment to different degrees will increase the U.S. carbon emission space and decrease its mitigation cost. However, the carbon emission space of other parties, including China, EU, and Japan, will be reduced and their mitigation costs will be increased. In 2030, under the 2 C target, the carbon price will increase by 4.4e14.6 US$ t1 in China, by 9.7e35.4 US$ t1 in the EU, and by 16.0e53.5 US$ t1 in Japan. In addition, China, EU, and Japan will incur additional Gross Domestic Production (GDP) loss. Under the 2 C target, the GDP loss of China would increase by US$22.0e71.1 billion (equivalent to 16.4e53.1 US$ per capita), the EU's GDP loss would increase by US$9.4e32.1 billion (equivalent to 20.7e71.1 US$ per capita), and Japan's GDP loss will increase by US$4.1e13.5 billion (equivalent to 34.3e111.6 US$ per capita).
基金Supported by the Priming Scientific Research Foundation for the junior researcher in Beijing Tongren Hospital,Capital Medical University(No.2018-YJJ-ZZL-034)。
文摘AIM: To evaluate the intra-operator repeatability of time domain and swept-source Fourier domain anterior segment optical coherence tomography(AS-OCT), namely, Visante ASOCT and Casia SS-1000 OCT, in measuring the preoperative parameters of implantable collamer lens(ICL) in myopic eyes, as well as the agreement between the two devices.METHODS: A total of 97 eyes from 49 myopes were investigated in this prospective case series study. The anterior chamber depth(ACD), angle-to-angle distance(ATA), pupil diameter(PD) and crystalline lens rise(CLR) in all subjects were measured for three times during one session by the same operator. The repeatability was evaluated using the within-subject standard deviation(Sw), repeatability limits and intraclass correlation coefficients(ICC). The agreement between the two systems was evaluated using the Bland-Altman plots and 95% limits of agreement(Lo A).RESULTS: The repeatability limits of Visante AS-OCT in measuring ACD, ATA, PD and CLR were 0.099, 0.141, 0.304, and 0.079 mm, respectively. The repeatability limits of Casia SS-1000 OCT in measuring ACD, ATA, PD, and CLR were 0.105, 0.127, 0.357, and 0.082 mm, respectively. Excellent repeatability could be attained in both devices, with the ICC>0.8 for all the measured variables. The interdevice agreement was excellent(P>0.05) for ACD and ATA, but poor(P<0.05) for PD and CLR.CONCLUSION: Good repeatability can be attained by time domain and swept-source Fourier-domain OCT for all the measured variables. Moreover, interdevice agreement analysis suggests that interchangeable measurements between two devices can be achieved for ACD and ATA, but not for PD and CLR;but the differences in measurements were not clinically significant.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61871205 and 61561033)the Major Academic Discipline and Technical Leader of Jiangxi Province,China(Grant No.20162BCB22011).
文摘A new efficient two-party semi-quantum key agreement protocol is proposed with high-dimensional single-particle states.Different from the previous semi-quantum key agreement protocols based on the two-level quantum system,the propounded protocol makes use of the advantage of the high-dimensional quantum system,which possesses higher efficiency and better robustness against eavesdropping.Besides,the protocol allows the classical participant to encode the secret key with qudit shifting operations without involving any quantum measurement abilities.The designed semi-quantum key agreement protocol could resist both participant attacks and outsider attacks.Meanwhile,the conjoint analysis of security and efficiency provides an appropriate choice for reference on the dimension of single-particle states and the number of decoy states.
基金Supported by the Direction General of Universities and Research(DGUI)of the Community of Madrid(No.CCG10-UCM/BIO-4889)
文摘AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus.METHODS: Stereoacuity was measured in two different sessions separated by a time interval of at least 24 h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular vision.RESULTS: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability(COR): ±13 and±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was noted.In the subjects with abnormal binocular vision, best repeatability was shown by the Frisby(COR: ±69s arc)and Randot(COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other tests.CONCLUSION:Therepeatabilityofstereoacuitymeasures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.
基金Supported by Health Commission of Hubei Province,China No.WJ2019M077 and No.WJ2019H227Natural Science Foundation of Hubei Province,China No.2019CFB286and Science and Technology Bureau of Shihezi,China No.2019ZH11.
文摘BACKGROUND Hepatocellular carcinoma is the most common primary liver malignancy.From the results of previous studies,Liver Imaging Reporting and Data System(LIRADS)on contrast-enhanced ultrasound(CEUS)has shown satisfactory diagnostic value.However,a unified conclusion on the interobserver stability of this innovative ultrasound imaging has not been determined.The present metaanalysis examined the interobserver agreement of CEUS LI-RADS to provide some reference for subsequent related research.AIM To evaluate the interobserver agreement of LI-RADS on CEUS and analyze the sources of heterogeneity between studies.METHODS Relevant papers on the subject of interobserver agreement on CEUS LI-RADS published before March 1,2020 in China and other countries were analyzed.The studies were filtered,and the diagnostic criteria were evaluated.The selected references were analyzed using the“meta”and“metafor”packages of R software version 3.6.2.RESULTS Eight studies were ultimately included in the present analysis.Meta-analysis results revealed that the summary Kappa value of included studies was 0.76[95%confidence interval,0.67-0.83],which shows substantial agreement.Higgins I2 statistics also confirmed the substantial heterogeneity(I2=91.30%,95%confidence interval,85.3%-94.9%,P<0.01).Meta-regression identified the variables,including the method of patient enrollment,method of consistency testing,and patient race,which explained the substantial study heterogeneity.CONCLUSION CEUS LI-RADS demonstrated overall substantial interobserver agreement,but heterogeneous results between studies were also obvious.Further clinical investigations should consider a modified recommendation about the experimental design.
文摘BACKGROUND Data regarding the agreement among multiple operators for measurement of quadriceps muscle thickness by bedside ultrasonography(USG)are sparse.AIM To statistically assess the agreement among 5 operators for measurement of quadriceps muscle thickness on bedside USG.METHODS This was a cross-sectional observational study.The 5 operators of varied experience(comprised of 1 critical care consultant,2 fellows,and 2 nurses)independently measured quadriceps muscle thickness in triplicate for 45 critically ill patients each,using USG.Intra-and interrater agreement rates among the 5 operators were assessed using intraclass correlation coefficient(ICC)and expressed with 95%confidence interval(CI).RESULTS The 5 operators produced a total of 135 readings and 675 observations for ICC calculations to determine the intraoperator and interoperator variations respectively.For intraoperator agreement,the overall ICC(95%CI)was 0.998(0.997,0.999)for operator 1,0.998(0.997,0.999)for operator 2,0.997(0.995,0.999)for operator 3,0.999(0.998,0.999)for operator 4,and 0.998(0.997,0.999)for operator 5.For interoperator agreement,the overall ICC(95%CI)was 0.977(0.965,0.986;P<0.001)for reading 1,0.974(0.960,0.984;P<0.001)for reading 2,and 0.975(0.961,0.985;P<0.001)for reading 3.CONCLUSION USG measurement of quadriceps muscle thickness was not dependent on clinical experience,supporting training for nurses in it.
基金supported by the Chinese Polar National Interests Assessment Program (Grant no.1701024)
文摘As the third legally-binding instrument of the Arctic Council, the Agreement on Enhancing International Arctic Scientific Cooperation was signed in May 2017 and entered into force on 23 May 2018. The Agreement not only reduces obstacles to the international scientific cooperation and promotes the movement of people and equipment across borders for the effective and efficient development of Arctic scientific knowledge, but also provides an improved international Arctic legal environment for conducting Arctic scientific cooperation based on UNCLOS and institutional arrangements. However, the observer states, the NGOs and IGOs, as well as Permanent Participants are rarely mentioned in this Agreement. This article chooses one group, non-Arctic states, as a case in point in order to critically discuss the influence of this new Arctic scientific cooperation agreement. It argues that the non-Arctic states are left behind at the original legal situation and trapped in an inferior status in Arctic science. Under these circumstances, this article suggests that non-Arctic states, especially those with competitive research abilities, should appeal for amendment of the Agreement to allow wider access to research areas and data sharing, especially when cooperating with the eight-member states of the Arctic Council. Also, non-Arctic states should take the Agreement as the reference when signing bilateral agreements with Arctic states so as to safeguard their interests when conducting Arctic scientific activities. Moreover, the active participation in other fora as well as various bilateral scientific projects can assist non-Arctic states to strengthen the relations with the Arctic states and build trust in the Arctic Council.
基金the National Social Science Foundation of China(17ZDA077)the Ministry of Science and Technology of China(2017YFA0605304).
文摘Article 6 of the Paris Agreement introduces two international carbon markets that receive extensive attention and are expected to play an important role in the post-2020 climate regime.Three key elements of the two international carbon markets,including the scope,the types of tradable units and the governance,are identified,as the basis to clarify their basic forms.Based on the key issues and their different designs identified in negotiations,this study analyzes the contributions and challenges for China to participate in international carbon markets.Considering the inherent needs of climate change mitigation,climate finance,the development of a green"Belt and Road"and the China South-South cooperation in climate change,along with the existing domestic capacities on market mechanisms,this study puts forward the short-,medium-and long-term development prospects of the two international carbon markets.
基金This work is supported by the Sichuan education department research project(No.16226483)Sichuan Science and Technology Program(No.2018GZDZX0008)+1 种基金Chengdu Science and Technology Program(No.2018-YF08-00007-GX)the National Natural Science Foundation of China(No.61872087).
文摘Multi-server authenticated key agreement schemes have attracted great attention to both academia and industry in recent years.However,traditional authenticated key agreement schemes in the single-server environment are not suitable for the multi-server environment because the user has to register on each server when he/she wishes to log in various servers for different service.Moreover,it is unreasonable to consider all servers are trusted since the server in a multi-server environment may be a semi-trusted party.In order to overcome these difficulties,we designed a secure three-factor multi-server authenticated key agreement protocol based on elliptic curve cryptography,which needs the user to register only once at the registration center in order to access all semi-trusted servers.The proposed scheme can not only against various known attacks but also provides high computational efficiency.Besides,we have proved our scheme fulfills mutual authentication by using the authentication test method.
文摘During the past decade,rapid advances in wireless communication technologies have made it possible for users to access desired services using hand-held devices.Service providers have hosted multiple servers to ensure seamless online services to end-users.To ensure the security of this online communication,researchers have proposed several multi-server authentication schemes incorporating various cryptographic primitives.Due to the low power and computational capacities of mobile devices,the hash-based multi-server authenticated key agreement schemes with offline Registration Server(RS)are the most efficient choice.Recently,Kumar-Om presented such a scheme and proved its security against all renowned attacks.However,we find that their scheme bears an incorrect login phase,and is unsafe to the trace attack,the Session-Specific Temporary Information Attack(SSTIA),and the Key Compromise Impersonation Attack(KCIA).In fact,all of the existing multi-server authentication schemes(hash-based with offline RS)do not withstand KCLA.To deal with this situation,we propose an improved hash-based multi-server authentication scheme(with offline RS).We analyze the security of the proposed scheme under the random oracle model and use the t4Automated Validation of Internet Security Protocols and Applications''(AVISPA)tool.The comparative analysis of communication overhead and computational complexity metrics shows the efficiency of the proposed scheme.