The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics...The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach： One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium.展开更多
In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalit...In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalities.Then a smoothing Newton-like method is proposed for solving the reformulated system,which only needs to solve one system of linear equations and to perform one line search at each iteration. The global and local quadratic convergence are studied under appropriate assumptions. Numerical examples show that the new approach is effective.展开更多
In this paper, we establish a new type of alternation theory for more general restricted ranges Chebyshev approximation with equalities. The uniqueness and strong uniqueness theorems are given. Applying the results, w...In this paper, we establish a new type of alternation theory for more general restricted ranges Chebyshev approximation with equalities. The uniqueness and strong uniqueness theorems are given. Applying the results, we obtain the alternation theorem and uniqueness theorem for best coposilive approximation.展开更多
Let A∈C<sup>m×n</sup>,set eigenvalues of matrix A with |λ<sub>1</sub> （A）|≥|λ<sub>2</sub>（A）|≥…≥|λ<sub>n</sub>（A）|,write A≥0 if A is a positive semid...Let A∈C<sup>m×n</sup>,set eigenvalues of matrix A with |λ<sub>1</sub> （A）|≥|λ<sub>2</sub>（A）|≥…≥|λ<sub>n</sub>（A）|,write A≥0 if A is a positive semidefinite Hermitian matrix, and denote∧<sub>k</sub> （A）=diag （λ<sub>1</sub>（A）,…,λ<sub>k</sub>（A））,∧<sub>(</sub>（n-k）.（A）=diag (λ<sub>k+1</sub>（A）,…,λ<sub>n</sub>（A）)for any k=1, 2,...,n if A≥0. Denote all n order unitary matrices by U<sup>n×n</sup>.Problem of equalities to hold in eigenvalue inequalities for products of matrices展开更多
In quantitative decision analysis, an analyst applies mathematical models to make decisions. Frequently these models involve an optimization problem to determine the values of the decision variables, a system </spa...In quantitative decision analysis, an analyst applies mathematical models to make decisions. Frequently these models involve an optimization problem to determine the values of the decision variables, a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> of possibly non</span></span><span style="font-family:Verdana;">- </span><span style="font-family:Verdana;">li</span><span style="font-family:Verdana;">near inequalities and equalities to restrict these variables, or both. In this</span><span style="font-family:""><span style="font-family:Verdana;"> note, </span><span style="font-family:Verdana;">we relate a general nonlinear programming problem to such a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> in</span><span style="font-family:Verdana;"> such </span><span style="font-family:Verdana;">a way as to provide a solution of either by solving the other—with certain l</span><span style="font-family:Verdana;">imitations. We first start with </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> and generalize phase 1 of the two-phase simplex method to either solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> or establish that a solution does not exist. A conclusion is reached by trying to solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by minimizing a sum of artificial variables subject to the system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> as constraints. Using examples, we illustrate </span><span style="font-family:Verdana;">how this approach can give the core of a cooperative game and an equili</span><span style="font-family:Verdana;">brium for a noncooperative game, as well as solve both linear and nonlinear goal programming problems. Similarly, we start with a general nonlinear programming problem and present an algorithm to solve it as a series of systems </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by generalizing the </span></span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">sliding objective</span><span style="font-family:Verdana;"> function </span><span style="font-family:Verdana;">method</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> for</span><span style="font-family:Verdana;"> two-dimensional linear programming. An example is presented to illustrate the geometrical nature of this approach.展开更多
We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks ...We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks equality, the evolution equations governing the characteristic functions of the probability density functions for the quantum work, and recent experimental verifications. Some resultsare given here for the first time. We particularly emphasize the formally structural consistence between these quantum equalities and their classical counterparts, which are useful for understanding the existing equalities and pursuing new fluctuation relations in other complex quantum systems.展开更多
Some rank equalities are established for anti-involutory matrices. In particular, we get the formulas for the rank of the difference, the sum and the commutator of anti-involutory matrices.
A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relati...A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then for all r≥1. We give sharper numerical radius inequality which states that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then ?where . Moreover, we give many numerical radius inequalities which are sharper than related inequalities proved recently, and several applications are given.展开更多
We prove weighted q-variation inequalities with 2<q<∞for sharp truncations of singular integral operators in higher dimensions.The vector-valued extensions of these inequalities are also given.Parallel results ...We prove weighted q-variation inequalities with 2<q<∞for sharp truncations of singular integral operators in higher dimensions.The vector-valued extensions of these inequalities are also given.Parallel results are proven for differential operators.展开更多
In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitte...In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitter configurations,this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE.The AFE is realized by implementing source degeneration transconductance,feedforward high-pass branch and inductive feedback peaking TIA.The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain.With the pro-posed AFE,the receiver demonstrates eye opening after digital FIR equalization and achieves 6×10^(-9) BER with a 29.6 dB inser-tion loss channel.展开更多
In this paper we generalize the results of [1]and prove that,for any given 4≤k≤n,theChern classes of hypersurface V_n corresponding to the partitions of k also satisfy some equalities.Furthermore,we obtain the equal...In this paper we generalize the results of [1]and prove that,for any given 4≤k≤n,theChern classes of hypersurface V_n corresponding to the partitions of k also satisfy some equalities.Furthermore,we obtain the equalities of Chern classes concretely for k=4,5,6.展开更多
In this paper, we deal with a Dirichlet problem for linear elliptic equations related to Gauss measure. For this problem, we study the converse of some inequalities proved by other authors, in the sense that we study ...In this paper, we deal with a Dirichlet problem for linear elliptic equations related to Gauss measure. For this problem, we study the converse of some inequalities proved by other authors, in the sense that we study the case of equalities and show that equalities are achieved only in the ＂symmetrized＂ situations. In addition, under other assumptions, we give a different form of comparison results and discuss the corresponding case of equalities.展开更多
On the evening of May 3Oth,the parallel forum"Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective",as part of the 4th Dialogue on ...On the evening of May 3Oth,the parallel forum"Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective",as part of the 4th Dialogue on Exchanges and Mutual Learning among Civilisations,was held in Dunhuang.The forum was organised by the China Writers Association and co-organised by China National Publications Import&Export(Group)Corporation.展开更多
A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement a...A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement at the same time.We analyze its inter-carrier interference/inter-symbol interference(ICI/ISI)over multipath channels.Owing to the additional CP,the ISI of received symbols over multipath channels is eliminated in the proposed system,and the resulting improvement in the signal-to-interference ratio(SIR)performance is evaluated by theoretical analysis.Moreover,for the ICI caused by multipath propagation in received symbols,we develop a method that eliminates the ICI by frequency-domain channel estimation and equalization before the receiver filtering process.The proposed CP-NO-FBMC-QAM system and ICI cancellation method(ICICM)are validated by comparisons of implementation complexity,power spectral density(PSD),bit error rate(BER)and channel estimation performance with conventional CP-based orthogonal frequency division multiplexing(CP-OFDM)and FBMC-QAM systems.展开更多
Under the background of accelerated global cultural exchange and information dissemination,reading has become a crucial component of public cultural services.Public libraries in Nordic countries(Denmark,Sweden,Norway,...Under the background of accelerated global cultural exchange and information dissemination,reading has become a crucial component of public cultural services.Public libraries in Nordic countries(Denmark,Sweden,Norway,Finland,Iceland)stand out by adhering to the core philosophy of“universal sharing and equal reading”,integrating reading promotion into national strategies,and constructing extensive service networks through sound legal guarantees and adequate financial support.This study identifies four key strategies for universality and equality in Nordic public libraries:covering all age groups,eliminating group differences,integrating digital and physical resources,and ensuring the right to read through legislative,financial,and other institutional support.These provide a reference for global public cultural services.展开更多
To improve image quality under low illumination conditions,a novel low-light image enhancement method is proposed in this paper based on multi-illumination estimation and multi-scale fusion(MIMS).Firstly,the illuminat...To improve image quality under low illumination conditions,a novel low-light image enhancement method is proposed in this paper based on multi-illumination estimation and multi-scale fusion(MIMS).Firstly,the illumination is processed by contrast-limited adaptive histogram equalization(CLAHE),adaptive complementary gamma function(ACG),and adaptive detail preserving S-curve(ADPS),respectively,to obtain three components.Then,the fusion-relevant features,exposure,and color contrast are selected as the weight maps.Subsequently,these components and weight maps are fused through multi-scale to generate enhanced illumination.Finally,the enhanced images are obtained by multiplying the enhanced illumination and reflectance.Compared with existing approaches,this proposed method achieves an average increase of 0.81%and 2.89%in the structural similarity index measurement(SSIM)and peak signal-to-noise ratio(PSNR),and a decrease of 6.17%and 32.61%in the natural image quality evaluator(NIQE)and gradient magnitude similarity deviation(GMSD),respectively.展开更多
THE world should be celebrating the creation of the United Nations(UN)80 years ago.However,its very existence is threatened.China recognizes the UN as the core of the international system.The UN Charter is a legal tre...THE world should be celebrating the creation of the United Nations(UN)80 years ago.However,its very existence is threatened.China recognizes the UN as the core of the international system.The UN Charter is a legal treaty under which national governments freely agree to uphold values and principles of behaviour.As a manifestation of the principle of“the sovereign equality of members,”each has an equal vote in the General Assembly.展开更多
Zn–Ag alloys are highly promising materials for fabricating biodegradable orthopedic implants.Nonetheless,they suffer from inferior strength.A Zn–2.5Ag alloy was alloyed with different contents of Mg(0.08,0.5,and 1 ...Zn–Ag alloys are highly promising materials for fabricating biodegradable orthopedic implants.Nonetheless,they suffer from inferior strength.A Zn–2.5Ag alloy was alloyed with different contents of Mg(0.08,0.5,and 1 wt.%)and then processed by equal channel angular pressing.Tensile tests and microstructure observation were conducted to investigate the impact of Mg addition on the microstructure and mechanical properties of Zn–2.5Ag alloy.Zn–2.5Ag alloy exhibits an ultrahigh elongation(EL)of 120.4%but a poor yield strength(YS)of 90.1 MPa,because of phase boundary sliding(PBS).Mg addition inhibits PBS and thus dramatically enhances YS but lowers EL.Specifically,YS of Zn–2.5Ag alloys containing Mg of 0.08%,0.5%,and 1%is 257.0,291.8,and 322.6 MPa,respectively.The alloys with 0.08%and 0.5%Mg possess an EL of around 30%,while the alloy with 1%Mg has an EL of only 11.0%.YS and EL of Zn–2.5Ag–0.5Mg alloy surpass that needed by orthopedic implants by 45.9%and 106.0%,respectively.Grain refinement strengthening is the main contributor to high strength.It is speculated that deformation twinning suppression and<c+a>pyramidal slip activation contribute to good ductility.展开更多
The effect of rotational-die equal channel angular pressing(RD-ECAP)temperature and deformation route on the microstructure and mechanical properties of pre-extruded Mg-5Gd-3Y-1Zn-0.5Zr(wt%)alloys were investigated.Th...The effect of rotational-die equal channel angular pressing(RD-ECAP)temperature and deformation route on the microstructure and mechanical properties of pre-extruded Mg-5Gd-3Y-1Zn-0.5Zr(wt%)alloys were investigated.The results indicate that the RD-ECAP updates both theα-Mg texture and long-period stack-ing ordered(LPSO)arrangement in the pre-extruded alloy,while theα-Mg texture is more sensitive to the change of deformation route.The LPSO streamlines modify the anisotropy of mechanical properties of the ECAP alloys via exerting different reinforcing effects and modifying the crack propagation.The lower ECAP temperature of 350℃ rather than 400℃ promotes dynamic precipitation which deteriorates the following ageing-hardening response but conduces to refining theα-Mg grains and preventing a sharp drop in elongation after peak ageing.The 350A peak-aged alloy exhibits the optimal mechanical proper-ties with the average tensile yield strength(TYS)of 311 MPa(S_(TYS)=3.7,S indicates standard deviation)and elongation of 7.6%(S_(EL)=0.7).Its higher strength should mainly be attributed to the finer grain size,and its quasi-isotropic performance should be inherited from the ECAP state induced by the rational arrangement of LPSO phases.展开更多
The Global Leaders’Meeting on Women was held in Beijing,the capital of China,on 13-14 October.South African Minister in the Presidency for Women,Youth and Persons with Disabilities Sindisiwe Chikunga,attended the eve...The Global Leaders’Meeting on Women was held in Beijing,the capital of China,on 13-14 October.South African Minister in the Presidency for Women,Youth and Persons with Disabilities Sindisiwe Chikunga,attended the event.ChinAfrica spoke with her in an exclusive interview about the messages she brought to the meeting,South Africa’s progress in women’s empowerment,how the G20 presidency can contribute to this cause,and China’s role.An edited excerpt of the interview follows.展开更多
基金The project supported in part by USA NIH Grant under HG002894
文摘The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach： One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium.
基金supported by Guangdong Provincial Zhujiang Scholar Award Project,National Science Foundation of China(10671163,10871031)the National Basic Research Program under the Grant 2005CB321703Scientific Research Fund of Hunan Provincial Education Department(06A069,06C824)
文摘In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalities.Then a smoothing Newton-like method is proposed for solving the reformulated system,which only needs to solve one system of linear equations and to perform one line search at each iteration. The global and local quadratic convergence are studied under appropriate assumptions. Numerical examples show that the new approach is effective.
文摘In this paper, we establish a new type of alternation theory for more general restricted ranges Chebyshev approximation with equalities. The uniqueness and strong uniqueness theorems are given. Applying the results, we obtain the alternation theorem and uniqueness theorem for best coposilive approximation.
基金Supported partly by National Natural Science Foundation of China
文摘Let A∈C<sup>m×n</sup>,set eigenvalues of matrix A with |λ<sub>1</sub> （A）|≥|λ<sub>2</sub>（A）|≥…≥|λ<sub>n</sub>（A）|,write A≥0 if A is a positive semidefinite Hermitian matrix, and denote∧<sub>k</sub> （A）=diag （λ<sub>1</sub>（A）,…,λ<sub>k</sub>（A））,∧<sub>(</sub>（n-k）.（A）=diag (λ<sub>k+1</sub>（A）,…,λ<sub>n</sub>（A）)for any k=1, 2,...,n if A≥0. Denote all n order unitary matrices by U<sup>n×n</sup>.Problem of equalities to hold in eigenvalue inequalities for products of matrices
文摘In quantitative decision analysis, an analyst applies mathematical models to make decisions. Frequently these models involve an optimization problem to determine the values of the decision variables, a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> of possibly non</span></span><span style="font-family:Verdana;">- </span><span style="font-family:Verdana;">li</span><span style="font-family:Verdana;">near inequalities and equalities to restrict these variables, or both. In this</span><span style="font-family:""><span style="font-family:Verdana;"> note, </span><span style="font-family:Verdana;">we relate a general nonlinear programming problem to such a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> in</span><span style="font-family:Verdana;"> such </span><span style="font-family:Verdana;">a way as to provide a solution of either by solving the other—with certain l</span><span style="font-family:Verdana;">imitations. We first start with </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> and generalize phase 1 of the two-phase simplex method to either solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> or establish that a solution does not exist. A conclusion is reached by trying to solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by minimizing a sum of artificial variables subject to the system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> as constraints. Using examples, we illustrate </span><span style="font-family:Verdana;">how this approach can give the core of a cooperative game and an equili</span><span style="font-family:Verdana;">brium for a noncooperative game, as well as solve both linear and nonlinear goal programming problems. Similarly, we start with a general nonlinear programming problem and present an algorithm to solve it as a series of systems </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by generalizing the </span></span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">sliding objective</span><span style="font-family:Verdana;"> function </span><span style="font-family:Verdana;">method</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> for</span><span style="font-family:Verdana;"> two-dimensional linear programming. An example is presented to illustrate the geometrical nature of this approach.
基金supported by the National Natural Science Foundation of China (Grant No. 11174025)
文摘We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks equality, the evolution equations governing the characteristic functions of the probability density functions for the quantum work, and recent experimental verifications. Some resultsare given here for the first time. We particularly emphasize the formally structural consistence between these quantum equalities and their classical counterparts, which are useful for understanding the existing equalities and pursuing new fluctuation relations in other complex quantum systems.
文摘Some rank equalities are established for anti-involutory matrices. In particular, we get the formulas for the rank of the difference, the sum and the commutator of anti-involutory matrices.
文摘A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then for all r≥1. We give sharper numerical radius inequality which states that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then ?where . Moreover, we give many numerical radius inequalities which are sharper than related inequalities proved recently, and several applications are given.
基金supported by National Natural Science Foundation of China(Grant Nos.11671308 and 11431011)Ministerio de Economia y Competitividad/al Fondo Europeo de Desarrollo Regional(Grant No.MTM2015-66157-C2-1-P)
文摘We prove weighted q-variation inequalities with 2<q<∞for sharp truncations of singular integral operators in higher dimensions.The vector-valued extensions of these inequalities are also given.Parallel results are proven for differential operators.
基金supported by National Key R&D Program of China No.2022YFB2803401.
文摘In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitter configurations,this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE.The AFE is realized by implementing source degeneration transconductance,feedforward high-pass branch and inductive feedback peaking TIA.The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain.With the pro-posed AFE,the receiver demonstrates eye opening after digital FIR equalization and achieves 6×10^(-9) BER with a 29.6 dB inser-tion loss channel.
文摘In this paper we generalize the results of [1]and prove that,for any given 4≤k≤n,theChern classes of hypersurface V_n corresponding to the partitions of k also satisfy some equalities.Furthermore,we obtain the equalities of Chern classes concretely for k=4,5,6.
基金Supported by the National Natural Science Foundation of China (Grant No 10401009)the Program for New Century Excellent Talents in University (Grant No 060275)
文摘In this paper, we deal with a Dirichlet problem for linear elliptic equations related to Gauss measure. For this problem, we study the converse of some inequalities proved by other authors, in the sense that we study the case of equalities and show that equalities are achieved only in the ＂symmetrized＂ situations. In addition, under other assumptions, we give a different form of comparison results and discuss the corresponding case of equalities.
文摘On the evening of May 3Oth,the parallel forum"Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective",as part of the 4th Dialogue on Exchanges and Mutual Learning among Civilisations,was held in Dunhuang.The forum was organised by the China Writers Association and co-organised by China National Publications Import&Export(Group)Corporation.
文摘A new cyclic prefix(CP)-based nonoverlapping FBMC-QAM(CP-NO-FBMC-QAM)system with two prototype filters is proposed in this paper,which satisfies complex orthogonality conditions and good frequency energy confinement at the same time.We analyze its inter-carrier interference/inter-symbol interference(ICI/ISI)over multipath channels.Owing to the additional CP,the ISI of received symbols over multipath channels is eliminated in the proposed system,and the resulting improvement in the signal-to-interference ratio(SIR)performance is evaluated by theoretical analysis.Moreover,for the ICI caused by multipath propagation in received symbols,we develop a method that eliminates the ICI by frequency-domain channel estimation and equalization before the receiver filtering process.The proposed CP-NO-FBMC-QAM system and ICI cancellation method(ICICM)are validated by comparisons of implementation complexity,power spectral density(PSD),bit error rate(BER)and channel estimation performance with conventional CP-based orthogonal frequency division multiplexing(CP-OFDM)and FBMC-QAM systems.
基金This paper is a phased research outcome of the 2023 Beijing International Studies University Regional and Country Studies Special Research Project titled“Reading Promotion in Nordic Public Libraries and Its Implications for China’s National Reading Development”(Project No.QYGB23A003).
文摘Under the background of accelerated global cultural exchange and information dissemination,reading has become a crucial component of public cultural services.Public libraries in Nordic countries(Denmark,Sweden,Norway,Finland,Iceland)stand out by adhering to the core philosophy of“universal sharing and equal reading”,integrating reading promotion into national strategies,and constructing extensive service networks through sound legal guarantees and adequate financial support.This study identifies four key strategies for universality and equality in Nordic public libraries:covering all age groups,eliminating group differences,integrating digital and physical resources,and ensuring the right to read through legislative,financial,and other institutional support.These provide a reference for global public cultural services.
基金supported by the National Key R&D Program of China(No.2022YFB3205101)NSAF(No.U2230116)。
文摘To improve image quality under low illumination conditions,a novel low-light image enhancement method is proposed in this paper based on multi-illumination estimation and multi-scale fusion(MIMS).Firstly,the illumination is processed by contrast-limited adaptive histogram equalization(CLAHE),adaptive complementary gamma function(ACG),and adaptive detail preserving S-curve(ADPS),respectively,to obtain three components.Then,the fusion-relevant features,exposure,and color contrast are selected as the weight maps.Subsequently,these components and weight maps are fused through multi-scale to generate enhanced illumination.Finally,the enhanced images are obtained by multiplying the enhanced illumination and reflectance.Compared with existing approaches,this proposed method achieves an average increase of 0.81%and 2.89%in the structural similarity index measurement(SSIM)and peak signal-to-noise ratio(PSNR),and a decrease of 6.17%and 32.61%in the natural image quality evaluator(NIQE)and gradient magnitude similarity deviation(GMSD),respectively.
文摘THE world should be celebrating the creation of the United Nations(UN)80 years ago.However,its very existence is threatened.China recognizes the UN as the core of the international system.The UN Charter is a legal treaty under which national governments freely agree to uphold values and principles of behaviour.As a manifestation of the principle of“the sovereign equality of members,”each has an equal vote in the General Assembly.
基金financial support of the National Natural Science Foundation of China(Nos.52001142 and 51975263).
文摘Zn–Ag alloys are highly promising materials for fabricating biodegradable orthopedic implants.Nonetheless,they suffer from inferior strength.A Zn–2.5Ag alloy was alloyed with different contents of Mg(0.08,0.5,and 1 wt.%)and then processed by equal channel angular pressing.Tensile tests and microstructure observation were conducted to investigate the impact of Mg addition on the microstructure and mechanical properties of Zn–2.5Ag alloy.Zn–2.5Ag alloy exhibits an ultrahigh elongation(EL)of 120.4%but a poor yield strength(YS)of 90.1 MPa,because of phase boundary sliding(PBS).Mg addition inhibits PBS and thus dramatically enhances YS but lowers EL.Specifically,YS of Zn–2.5Ag alloys containing Mg of 0.08%,0.5%,and 1%is 257.0,291.8,and 322.6 MPa,respectively.The alloys with 0.08%and 0.5%Mg possess an EL of around 30%,while the alloy with 1%Mg has an EL of only 11.0%.YS and EL of Zn–2.5Ag–0.5Mg alloy surpass that needed by orthopedic implants by 45.9%and 106.0%,respectively.Grain refinement strengthening is the main contributor to high strength.It is speculated that deformation twinning suppression and<c+a>pyramidal slip activation contribute to good ductility.
基金supported by the National Natural Science Foundation of China(No.51904036)the Hunan Provincial Key Research and Development Program(No.2023GK2049).
文摘The effect of rotational-die equal channel angular pressing(RD-ECAP)temperature and deformation route on the microstructure and mechanical properties of pre-extruded Mg-5Gd-3Y-1Zn-0.5Zr(wt%)alloys were investigated.The results indicate that the RD-ECAP updates both theα-Mg texture and long-period stack-ing ordered(LPSO)arrangement in the pre-extruded alloy,while theα-Mg texture is more sensitive to the change of deformation route.The LPSO streamlines modify the anisotropy of mechanical properties of the ECAP alloys via exerting different reinforcing effects and modifying the crack propagation.The lower ECAP temperature of 350℃ rather than 400℃ promotes dynamic precipitation which deteriorates the following ageing-hardening response but conduces to refining theα-Mg grains and preventing a sharp drop in elongation after peak ageing.The 350A peak-aged alloy exhibits the optimal mechanical proper-ties with the average tensile yield strength(TYS)of 311 MPa(S_(TYS)=3.7,S indicates standard deviation)and elongation of 7.6%(S_(EL)=0.7).Its higher strength should mainly be attributed to the finer grain size,and its quasi-isotropic performance should be inherited from the ECAP state induced by the rational arrangement of LPSO phases.
文摘The Global Leaders’Meeting on Women was held in Beijing,the capital of China,on 13-14 October.South African Minister in the Presidency for Women,Youth and Persons with Disabilities Sindisiwe Chikunga,attended the event.ChinAfrica spoke with her in an exclusive interview about the messages she brought to the meeting,South Africa’s progress in women’s empowerment,how the G20 presidency can contribute to this cause,and China’s role.An edited excerpt of the interview follows.
