2011 MARKS the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip gave another boost...2011 MARKS the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip gave another boost to the burgeoning China-Africa ties,said Chinese Vice Foreign Minister Zhai Jun.Hui visited five African countries - Mauritius, Zambia,the Democratic Republic of the Congo,Cameroon and Senegal -from January 6 to 19.Agriculture and trade were some of the most promising areas of cooperation between China and these countries,said Zhai in a recent interview with ChinAfrica.Excerpts follow:展开更多
The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boo...The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boosted burgeoning China-Africa ties, said Chinese Vice Foreign Minister Zhai Jun.展开更多
The unique Tulou homes of the Hakka people reflect a family-based society without class boundaries It all started with a mistake that brought Fujian Province’s peculiar earthen Tulou houses to the world’s attention....The unique Tulou homes of the Hakka people reflect a family-based society without class boundaries It all started with a mistake that brought Fujian Province’s peculiar earthen Tulou houses to the world’s attention. In the 1960s, the U.S. intelligence agency found round structures that resembled a nuclear facility hidden in the mountains. On further inspection the buildings turned out to be ancient residential compounds bustling with family life.展开更多
THE year 1995 was very special for Cai Shuzhen. In addition to having net earnings of 400,000 yuan, Cai retired an outstanding loan and invested 780,000 yuan in farm machinery. Local villagers found these achievements...THE year 1995 was very special for Cai Shuzhen. In addition to having net earnings of 400,000 yuan, Cai retired an outstanding loan and invested 780,000 yuan in farm machinery. Local villagers found these achievements surprising, for Cai had over the past years become notorious for undertakings which failed despite展开更多
At the point of death,a human being only has had the experience of nonexistence before birth and the experience of having lived his/her life after they were born.In the final analysis from the perspective of strict em...At the point of death,a human being only has had the experience of nonexistence before birth and the experience of having lived his/her life after they were born.In the final analysis from the perspective of strict empiricism,the individual only has two options:the nonexistence before birth or the eventual reliving of one’s life.The return of one’s life is supported by the paradigm of a multiverse and an antimatter universe.This is atheism’s logical certainty.展开更多
Precipitation via thermal treatments is among the most effective approaches to strengthening and is widely applied in the Al industry. Thermal treatments combined with deformation are capable of finely regulating the ...Precipitation via thermal treatments is among the most effective approaches to strengthening and is widely applied in the Al industry. Thermal treatments combined with deformation are capable of finely regulating the process of precipitation and distribution of precipitates. Deformation-induced defects exert significant impacts on the precipitation and already present precipitates, which however is often overlooked. In this study, the interactions between deformation and precipitation/precipitates, and their impacts on mechanical properties were systematically investigated in the solution-treated (ST) Al-0.61Mg-1.17Si-0.5Cu (wt.%), processed by multi-pass equal channel angular pressing (ECAP) and thermal treatments. Novel deformation-mediated cyclic evolution of precipitates is discovered: ST→ (1,2 passes: deformation induced precipitation) Guinier Preston (GP) zones→ (An250/30) Q’ and L phases→ (3-pass: deformation induced fragmentation/resolution) spherical precipitates→ (4-pass: deformation induced further fragmentation/resolution) GP zones. On this basis, we extend the quasi-binary phase diagram of Al-Mg_(2)Si along deformation as the third dimension and construct an innovative defect phase diagram for the Al-Mg-Si-based system. To testify to the effect of deformation-mediated cyclic evolution of precipitation/precipitates on the optimum mechanical properties, peak-aging treatments were performed in samples of ST and 3-pass states. Based on the microscopic characterizations, a distinctive mechanism of peak-aging strengthening is proposed. Notably in the 3-pass ECAPed and peak-aged sample the dominant strengthening phases become the L precipitates that thrived from the segmented and spherical L phases, rather than β’’ precipitates in the solely peak-aged ST sample. Our work provides a feasible example for exploring the combined processing technique of multi-step deformation and thermal treatments, to optimize the mechanical properties.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
To investigate the effect of microstructure evolution on corrosion behavior and strengthening mechanism of Mg-1Zn-1Ca(wt.%)alloys,as-cast Mg-1Zn-1Ca alloys were performed by equal channel angular pressing(ECAP)with 1 ...To investigate the effect of microstructure evolution on corrosion behavior and strengthening mechanism of Mg-1Zn-1Ca(wt.%)alloys,as-cast Mg-1Zn-1Ca alloys were performed by equal channel angular pressing(ECAP)with 1 and 4 passes.The corrosion behavior and mechanical properties of alloys were investigated by optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),electrochemical tests,immersion tests and tensile tests.The results showed that mechanical properties improved after ECAP 1 pass;however,the corrosion resistance deteriorated due to high-density dislocations and fragmented secondary phases by ECAP.In contrast,synchronous improvement in the mechanical properties and corrosion resistance was achieved though grain refinement after ECAP 4 passes;fine grains led to a significant improvement in the yield strength,ultimate tensile strength,elongation,and corrosion rate of 103 MPa,223 MPa,30.5%,and 1.5843 mm/a,respectively.The enhanced corrosion resistance was attributed to the formation of dense corrosion product films by finer grains and the barrier effect by high-density grain boundaries.These results indicated that Mg-1Zn-1Ca alloy has a promising potential for application in biomedical materials.展开更多
China’s healthcare system faces increasing challenges,including surging medical costs,resource allocation imbalances favoring large hospitals,and ineffective referral mechanisms.The lack of a unified strategy integra...China’s healthcare system faces increasing challenges,including surging medical costs,resource allocation imbalances favoring large hospitals,and ineffective referral mechanisms.The lack of a unified strategy integrating standardized coverage with personalized payment compounds these issues.To this end,this study proposes a risk-sharing reform strategy that combines equal coverage for the same disease(ECSD)with an individualized out-of-pocket(I-OOP)model.Specifically,the study employs a Markov model to capture patient transitions across health states and care levels.The findings show that ECSD and I-OOP enhance equity by standardizing disease coverage while tailoring costs to patient income and facility type.This approach alleviates demand on high-tier hospitals,promoting primary care utilization and enabling balanced resource distribution.The study’s findings provide a reference for policymakers and healthcare administrators by presenting a scalable framework that is aligned with China’s development goals with the aim of fostering an efficient,sustainable healthcare system that is adaptable to regional needs.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
Thirty years ago,Beijing hosted the Fourth World Conference on Women,which adopted the landmark Beijing Declaration and Platform for Action.This milestone document proclaimed for the first time that“Women’s rights a...Thirty years ago,Beijing hosted the Fourth World Conference on Women,which adopted the landmark Beijing Declaration and Platform for Action.This milestone document proclaimed for the first time that“Women’s rights are human rights,”formally introduced“gender mainstreaming”as a global strategy to advance gender equality,and a!rmed women’s equal rights across 12 key areas including politics,the economy,and culture.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
文摘2011 MARKS the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip gave another boost to the burgeoning China-Africa ties,said Chinese Vice Foreign Minister Zhai Jun.Hui visited five African countries - Mauritius, Zambia,the Democratic Republic of the Congo,Cameroon and Senegal -from January 6 to 19.Agriculture and trade were some of the most promising areas of cooperation between China and these countries,said Zhai in a recent interview with ChinAfrica.Excerpts follow:
文摘The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boosted burgeoning China-Africa ties, said Chinese Vice Foreign Minister Zhai Jun.
文摘The unique Tulou homes of the Hakka people reflect a family-based society without class boundaries It all started with a mistake that brought Fujian Province’s peculiar earthen Tulou houses to the world’s attention. In the 1960s, the U.S. intelligence agency found round structures that resembled a nuclear facility hidden in the mountains. On further inspection the buildings turned out to be ancient residential compounds bustling with family life.
文摘THE year 1995 was very special for Cai Shuzhen. In addition to having net earnings of 400,000 yuan, Cai retired an outstanding loan and invested 780,000 yuan in farm machinery. Local villagers found these achievements surprising, for Cai had over the past years become notorious for undertakings which failed despite
文摘At the point of death,a human being only has had the experience of nonexistence before birth and the experience of having lived his/her life after they were born.In the final analysis from the perspective of strict empiricism,the individual only has two options:the nonexistence before birth or the eventual reliving of one’s life.The return of one’s life is supported by the paradigm of a multiverse and an antimatter universe.This is atheism’s logical certainty.
基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20187,52171007,52371111,and 52371177).
文摘Precipitation via thermal treatments is among the most effective approaches to strengthening and is widely applied in the Al industry. Thermal treatments combined with deformation are capable of finely regulating the process of precipitation and distribution of precipitates. Deformation-induced defects exert significant impacts on the precipitation and already present precipitates, which however is often overlooked. In this study, the interactions between deformation and precipitation/precipitates, and their impacts on mechanical properties were systematically investigated in the solution-treated (ST) Al-0.61Mg-1.17Si-0.5Cu (wt.%), processed by multi-pass equal channel angular pressing (ECAP) and thermal treatments. Novel deformation-mediated cyclic evolution of precipitates is discovered: ST→ (1,2 passes: deformation induced precipitation) Guinier Preston (GP) zones→ (An250/30) Q’ and L phases→ (3-pass: deformation induced fragmentation/resolution) spherical precipitates→ (4-pass: deformation induced further fragmentation/resolution) GP zones. On this basis, we extend the quasi-binary phase diagram of Al-Mg_(2)Si along deformation as the third dimension and construct an innovative defect phase diagram for the Al-Mg-Si-based system. To testify to the effect of deformation-mediated cyclic evolution of precipitation/precipitates on the optimum mechanical properties, peak-aging treatments were performed in samples of ST and 3-pass states. Based on the microscopic characterizations, a distinctive mechanism of peak-aging strengthening is proposed. Notably in the 3-pass ECAPed and peak-aged sample the dominant strengthening phases become the L precipitates that thrived from the segmented and spherical L phases, rather than β’’ precipitates in the solely peak-aged ST sample. Our work provides a feasible example for exploring the combined processing technique of multi-step deformation and thermal treatments, to optimize the mechanical properties.
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.
基金financially supported by the National Natural Science Foundation of China(No.52374395)the Natural Science Foundation of Shanxi Province,China(Nos.20210302123135,202303021221143)+5 种基金the Scientific and Technological Achievements Transformation Guidance Special Project of Shanxi Province,China(Nos.202104021301022,202204021301009)the Central Government Guided Local Science and Technology Development Projects,China(No.YDZJSX20231B003)the Ministry of Science and Higher Education of the Russian Federation for financial support under the Megagrant(No.075-15-2022-1133)the National Research Foundation(NRF)grant funded by the Ministry of Science and ICT of Korea through the Research Institute of Advanced Materials(No.2015R1A2A1A01006795)the China Postdoctoral Science Foundation(No.2022M710541)the Research Project supported by Shanxi Scholarship Council of China(No.2022-038)。
文摘To investigate the effect of microstructure evolution on corrosion behavior and strengthening mechanism of Mg-1Zn-1Ca(wt.%)alloys,as-cast Mg-1Zn-1Ca alloys were performed by equal channel angular pressing(ECAP)with 1 and 4 passes.The corrosion behavior and mechanical properties of alloys were investigated by optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),electrochemical tests,immersion tests and tensile tests.The results showed that mechanical properties improved after ECAP 1 pass;however,the corrosion resistance deteriorated due to high-density dislocations and fragmented secondary phases by ECAP.In contrast,synchronous improvement in the mechanical properties and corrosion resistance was achieved though grain refinement after ECAP 4 passes;fine grains led to a significant improvement in the yield strength,ultimate tensile strength,elongation,and corrosion rate of 103 MPa,223 MPa,30.5%,and 1.5843 mm/a,respectively.The enhanced corrosion resistance was attributed to the formation of dense corrosion product films by finer grains and the barrier effect by high-density grain boundaries.These results indicated that Mg-1Zn-1Ca alloy has a promising potential for application in biomedical materials.
基金The National Natural Science Foundation of China(No.72071042)。
文摘China’s healthcare system faces increasing challenges,including surging medical costs,resource allocation imbalances favoring large hospitals,and ineffective referral mechanisms.The lack of a unified strategy integrating standardized coverage with personalized payment compounds these issues.To this end,this study proposes a risk-sharing reform strategy that combines equal coverage for the same disease(ECSD)with an individualized out-of-pocket(I-OOP)model.Specifically,the study employs a Markov model to capture patient transitions across health states and care levels.The findings show that ECSD and I-OOP enhance equity by standardizing disease coverage while tailoring costs to patient income and facility type.This approach alleviates demand on high-tier hospitals,promoting primary care utilization and enabling balanced resource distribution.The study’s findings provide a reference for policymakers and healthcare administrators by presenting a scalable framework that is aligned with China’s development goals with the aim of fostering an efficient,sustainable healthcare system that is adaptable to regional needs.
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.
文摘Thirty years ago,Beijing hosted the Fourth World Conference on Women,which adopted the landmark Beijing Declaration and Platform for Action.This milestone document proclaimed for the first time that“Women’s rights are human rights,”formally introduced“gender mainstreaming”as a global strategy to advance gender equality,and a!rmed women’s equal rights across 12 key areas including politics,the economy,and culture.
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.
