The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- serve...The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon ( including top-, web- and bottom plate tendons) on the stress and deflection of the main beam, and find out the optimal position of post tendon.展开更多
For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflect...For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.展开更多
BACKGROUND Percutaneous hepatobiliary drainage(PTCD)is an effective method for the treatment of biliary obstruction and other diseases,but postoperative complications are still one of the important problems faced by p...BACKGROUND Percutaneous hepatobiliary drainage(PTCD)is an effective method for the treatment of biliary obstruction and other diseases,but postoperative complications are still one of the important problems faced by patients.Continuous nursing is a comprehensive nursing model that plays an important role in postoperative recovery.The purpose of this study was to investigate the effect of continuous nursing on the incidence of complications in patients after PTCD surgery through meta-analysis and to evaluate its efficacy and safety.AIM To evaluate the effect of extended nursing on the incidence of complications in discharged patients after percutaneous transhepatic biliary drainage(PTBD).METHODS Randomized controlled studies on PTBD postdischarge extended care were identified in the CNKI,Wanfang,VIP,CBM,PubMed,Cochrane Library,Embase,Web of Science,and other databases.The quality of the included studies was evaluated using the Joanna Briggs Institute of Australia literature quality evaluation tool,and a meta-analysis of the included studies was performed with RevMan 5.4 software.RESULTS Finally,9 studies were included,with a total sample size of 854 patients(425 patients in the control group and 429 patients in the intervention group).Meta-analysis revealed that extended care effectively reduced biliary tract infection(RR:0.42,95%CI:0.30-0.57),puncture wound infection(RR:0.19,95%CI:0.06-0.65),catheter protrusion or displacement in discharged patients after PTBD(RR:0.31,95%CI:0.18-0.54),catheter blockage(RR:0.23,95%CI:0.13-0.42),skin infection around the drainage tube(RR:0.30,95%CI:0.12-0.77),and catheter-related readmissions(RR:0.34,95%CI:0.18-0.65)(P<0.05).CONCLUSION Compared with conventional discharge care,extended care can effectively reduce the occurrence of complications such as biliary tract infection,puncture wound infection,catheter prolapse or displacement,catheter blockage,skin infection around the drainage tube,and catheter-related readmission in discharged patients after PTBD.展开更多
Cambodia,funded and developed by China National Heavy Machinery Corporation(CHMC).This project has an installed capacity of 150 MW.Having completed its water storage in 2023,the plant,once operational,will provide Cam...Cambodia,funded and developed by China National Heavy Machinery Corporation(CHMC).This project has an installed capacity of 150 MW.Having completed its water storage in 2023,the plant,once operational,will provide Cambodia with a stable power supply.Moreover,CHMC has signed a Memorandum of Understanding to develop the 1,000 MW Upper Stung Tatay Pumped Storage Power Station-a key project,and the signing was witnessed by leaders of both countries.It will serve as a critical reserve and regulating power source in Cambodia,laying a foundation for subsequent renewable energy development in the country.展开更多
In response to the severe challenges posed by global climate change and the sustainable development goals of reaching peak carbon emissions and achieving carbon neutrality, green development has become a shared object...In response to the severe challenges posed by global climate change and the sustainable development goals of reaching peak carbon emissions and achieving carbon neutrality, green development has become a shared objective and necessity for economic growth and social transformation worldwide. China and the ASEAN countries share extensive common interests and positions on addressing climate change. Both have consistently emphasized green and sustainable development in their pursuit of shared prosperity. They have engaged in extensive practical cooperation in areas such as ecological conservation and clean energy.展开更多
On May 30,t he Ch ina Council for the Promotion of International Trade(CCPIT)held a regular press conference.Zhao Ping,the spokesperson for the CCPIT,said that since the beginning of this year,the number of issued ATA...On May 30,t he Ch ina Council for the Promotion of International Trade(CCPIT)held a regular press conference.Zhao Ping,the spokesperson for the CCPIT,said that since the beginning of this year,the number of issued ATA Carnets has increased significantly,reflecting the fact that China’s foreign trade policy portfolio is taking effect,foreign trade enterprises have been more active,and their motivation and enthusiasm for expanding the international market have continued to rise.展开更多
In 2023, the global economy faced multiple challenges and opportunities. It was pummeled by inflation, geopolitical tensions, and trade conflict while structural changes took place with a transition from old to new dr...In 2023, the global economy faced multiple challenges and opportunities. It was pummeled by inflation, geopolitical tensions, and trade conflict while structural changes took place with a transition from old to new drivers of growth, the mushrooming emerging industries, and the reshaping of the global value chains.展开更多
The effect of concrete creep on the pre-camber of a long-span pre-stressed concrete continuous rigid-frame bridge constructed by cantilever casting method was investigated.The difference of creep coefficients calculat...The effect of concrete creep on the pre-camber of a long-span pre-stressed concrete continuous rigid-frame bridge constructed by cantilever casting method was investigated.The difference of creep coefficients calculated with two Chinese codes was discussed.Based on the calculations,the pre-camber of a pre-stressed concrete continuous rigid-frame box bridge was computed for construction control purpose.The results show that the short-term creep coefficient and long-term creep coefficient calculated with the CC-1985 are larger than those calculated with the CC-2004,while the medium-term creep coefficient calculated with the CC-1985 is smaller than that calculated with the CC-2004.The difference of creep deformation calculated with these two codes is small,and the influences of concrete creep on the pre-camber for most of the segments are negligible.The deflections and stresses of the box girder measured during the construction stages agree very well with the predictions.展开更多
Bangladeshi textile and garment sectors defied the global challenges over the last five years and continued to grow although the growth momentum was not so strong before the COVID-19 pandemic.Before the start of the p...Bangladeshi textile and garment sectors defied the global challenges over the last five years and continued to grow although the growth momentum was not so strong before the COVID-19 pandemic.Before the start of the pandemic,both the textile and garment sectors were growing at a higher rate because of rising demand from the international clothing retailers and brands because of two main reasons including the trade war between USA and China and competitive prices of locally made garment.展开更多
The central bank data shows Bangladesh's import of RMG raw materials such as raw cotton,yarn,fabric and dyeing materials was US$7.92 billion in the first half of FY'24.The BGMEA reports Bangladesh's appare...The central bank data shows Bangladesh's import of RMG raw materials such as raw cotton,yarn,fabric and dyeing materials was US$7.92 billion in the first half of FY'24.The BGMEA reports Bangladesh's apparel exports are 71 per cent cotton-based.The country,however,meets 99 per cent of its cotton demand through imports.After Brazil,India is the second la rgest cotton supplier to Bangladesh and holds a 12 per cent market share,according to United States Department of Agriculture (USDA).展开更多
With the current rapid development of urbanization in China,people's living standards have been greatly improved.In the context of such a development background,the requirements for road traffic are getting more s...With the current rapid development of urbanization in China,people's living standards have been greatly improved.In the context of such a development background,the requirements for road traffic are getting more stringent,especially for bridge projects.The arched continuous rigid-frame bridge was developed under this social background.The advantage of the bridge lies in the design of a bridge model that integrates various functions such as transportation,landscape,and sightseeing.Based on the above,this paper first refers to the case to analyze the design and construction strategy of the arched continuous rigid-frame bridge,in hope of providing a valuable reference for relevant personnel.展开更多
In this study a 3D numerical analysis approach is developed to predict the ground vibration around rigid-frame viaducts induced by running high-speed trains. The train-bridge-ground interaction system is divided into ...In this study a 3D numerical analysis approach is developed to predict the ground vibration around rigid-frame viaducts induced by running high-speed trains. The train-bridge-ground interaction system is divided into two subsystems: the train-bridge interaction and the soil-structure interaction. First, the analytical program to simulate bridge vibration with consideration of train-bridge interaction is developed to obtain the vibration reaction forces at the pier bottoms. The high- speed train is described by a multi-DOFs vibration system and the rigid-frame viaduct is modeled with 3D beam elements. Second, applying these vibration reaction forces as input external excitations, the ground vibration is simulated by using a general-purpose program that includes soil-structure interaction effects. The validity of the analytical procedure is confirmed by comparing analytical and experimental results. The characteristics of high-speed train-induced vibrations, including the location of predominant vibration, are clarified. Based on this information a proposed vibration countermeasure using steel strut and new barrier is found effective in reducing train-induced vibrations and it satisfies environmental vibration requirements. The vibration screening efficiency is evaluated by reduction VAL based on 1/3 octave band spectral analysis.展开更多
There are many accelerating convergence factors (ACFs) for limit periodic continued fraction K(an/1)(an→a≠0). In this paper, some characteristics and comparative theorems are ob tained on ACFs. Two results are given...There are many accelerating convergence factors (ACFs) for limit periodic continued fraction K(an/1)(an→a≠0). In this paper, some characteristics and comparative theorems are ob tained on ACFs. Two results are given for most frequently used ACFs.展开更多
A famous theorem of Szemer'edi asserts that any subset of integers with posi- tive upper density contains arbitrarily arithmetic progressions. Let Fq be a finite field with q elements and Fq((X^-1)) be the power ...A famous theorem of Szemer'edi asserts that any subset of integers with posi- tive upper density contains arbitrarily arithmetic progressions. Let Fq be a finite field with q elements and Fq((X^-1)) be the power field of formal series with coefficients lying in Fq. In this paper, we concern with the analogous Szemeredi problem for continued fractions of Laurent series: we will show that the set of points x ∈ Fq((X-1)) of whose sequence of degrees of partial quotients is strictly increasing and contain arbitrarily long arithmetic progressions is of Hausdorff dimension 1/2.展开更多
The significant increase in the number of older adults in China,coupled with continuing industrialization and urbanization,has profound social and economic ramifications,including the evolution of major challenges to ...The significant increase in the number of older adults in China,coupled with continuing industrialization and urbanization,has profound social and economic ramifications,including the evolution of major challenges to public health,elder care services,policy-making,and the nation’s healthcare system.While the unprecedented changes in political and economic structures have obviously increased China’s productivity and revenues,what is less well understood is how they展开更多
We consider the block matrices and 3-dimensional graph manifolds associated with a special type of tree graphs. We demonstrate that the linking matrices of these graph manifolds coincide with the reduced matrices obta...We consider the block matrices and 3-dimensional graph manifolds associated with a special type of tree graphs. We demonstrate that the linking matrices of these graph manifolds coincide with the reduced matrices obtained from the Laplacian block matrices by means of Gauss partial diagonalization procedure described explicitly by W. Neumann. The linking matrix is an important topological invariant of a graph manifold which is possible to interpret as a matrix of coupling constants of gauge interaction in Kaluza-Klein approach, where 3-dimensional graph manifold plays the role of internal space in topological 7-dimensional BF theory. The Gauss-Neumann method gives us a simple algorithm to calculate the linking matrices of graph manifolds and thus the coupling constants matrices.展开更多
For a univariate function given by its Taylor series expansion, a continued fraction expansion can be obtained with the Viscovatov's algorithm, as the limiting value of a Thiele interpolating continued fraction or by...For a univariate function given by its Taylor series expansion, a continued fraction expansion can be obtained with the Viscovatov's algorithm, as the limiting value of a Thiele interpolating continued fraction or by means of the determinantal formulas for inverse and reciprocal differences with coincident data points. In this paper, both Viscovatov-like algorithms and Taylor-like expansions are incorporated to yield bivariate blending continued expansions which are computed as the limiting value of bivariate blending rational interpolants, which are constructed based on symmetric blending differences. Numerical examples are given to show the effectiveness of our methods.展开更多
Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=in...Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=inf{s≥0:∑n≥1an^(-s)(x)<∞}.展开更多
Modem and efficient methods focus on signal analysis and have drawn researchers' attention to it in recent years. These methods mainly include Continuous Wavelet and Wavelet Packet transforms. The main advantage of t...Modem and efficient methods focus on signal analysis and have drawn researchers' attention to it in recent years. These methods mainly include Continuous Wavelet and Wavelet Packet transforms. The main advantage of the application of these Wavelets is their capacity to analyze the signal position in different occasions and places. However, in sites with high frequencies its resolution becomes much more difficult. Wavelet packet transform is a more advanced form of continuous wavelets and can make a perfect level by level resolution for each signal. Although very few studies have been done in the field. In order to do this, in the present study, f^st there was an attempt to do a modal analysis on the structure by the ANSYS finite elements software, then using MATLAB, the wavelet was investigated through a continuous wavelet analysis. Finally the results were displayed in 2-D location-coefficient figures. In the second form, transient-dynamic analysis was done on the structure to find out the characteristics of the damage and the wavelet packet energy rate index was suggested. The results indicate that suggested index in the second form is both practical and applicable, and also this index is sensitive to the intensity of the damage.展开更多
文摘The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon ( including top-, web- and bottom plate tendons) on the stress and deflection of the main beam, and find out the optimal position of post tendon.
基金supported by the Scientific Research Fund of Hunan Provincial Education Department(21B0070)the Natural Science Foundation of Jiangsu Province(BK20231452)+1 种基金the Fundamental Research Funds for the Central Universities(30922010809)the National Natural Science Foundation of China(11801591,11971195,12071171,12171107,12201207,12371072)。
文摘For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.
文摘BACKGROUND Percutaneous hepatobiliary drainage(PTCD)is an effective method for the treatment of biliary obstruction and other diseases,but postoperative complications are still one of the important problems faced by patients.Continuous nursing is a comprehensive nursing model that plays an important role in postoperative recovery.The purpose of this study was to investigate the effect of continuous nursing on the incidence of complications in patients after PTCD surgery through meta-analysis and to evaluate its efficacy and safety.AIM To evaluate the effect of extended nursing on the incidence of complications in discharged patients after percutaneous transhepatic biliary drainage(PTBD).METHODS Randomized controlled studies on PTBD postdischarge extended care were identified in the CNKI,Wanfang,VIP,CBM,PubMed,Cochrane Library,Embase,Web of Science,and other databases.The quality of the included studies was evaluated using the Joanna Briggs Institute of Australia literature quality evaluation tool,and a meta-analysis of the included studies was performed with RevMan 5.4 software.RESULTS Finally,9 studies were included,with a total sample size of 854 patients(425 patients in the control group and 429 patients in the intervention group).Meta-analysis revealed that extended care effectively reduced biliary tract infection(RR:0.42,95%CI:0.30-0.57),puncture wound infection(RR:0.19,95%CI:0.06-0.65),catheter protrusion or displacement in discharged patients after PTBD(RR:0.31,95%CI:0.18-0.54),catheter blockage(RR:0.23,95%CI:0.13-0.42),skin infection around the drainage tube(RR:0.30,95%CI:0.12-0.77),and catheter-related readmissions(RR:0.34,95%CI:0.18-0.65)(P<0.05).CONCLUSION Compared with conventional discharge care,extended care can effectively reduce the occurrence of complications such as biliary tract infection,puncture wound infection,catheter prolapse or displacement,catheter blockage,skin infection around the drainage tube,and catheter-related readmission in discharged patients after PTBD.
文摘Cambodia,funded and developed by China National Heavy Machinery Corporation(CHMC).This project has an installed capacity of 150 MW.Having completed its water storage in 2023,the plant,once operational,will provide Cambodia with a stable power supply.Moreover,CHMC has signed a Memorandum of Understanding to develop the 1,000 MW Upper Stung Tatay Pumped Storage Power Station-a key project,and the signing was witnessed by leaders of both countries.It will serve as a critical reserve and regulating power source in Cambodia,laying a foundation for subsequent renewable energy development in the country.
文摘In response to the severe challenges posed by global climate change and the sustainable development goals of reaching peak carbon emissions and achieving carbon neutrality, green development has become a shared objective and necessity for economic growth and social transformation worldwide. China and the ASEAN countries share extensive common interests and positions on addressing climate change. Both have consistently emphasized green and sustainable development in their pursuit of shared prosperity. They have engaged in extensive practical cooperation in areas such as ecological conservation and clean energy.
文摘On May 30,t he Ch ina Council for the Promotion of International Trade(CCPIT)held a regular press conference.Zhao Ping,the spokesperson for the CCPIT,said that since the beginning of this year,the number of issued ATA Carnets has increased significantly,reflecting the fact that China’s foreign trade policy portfolio is taking effect,foreign trade enterprises have been more active,and their motivation and enthusiasm for expanding the international market have continued to rise.
文摘In 2023, the global economy faced multiple challenges and opportunities. It was pummeled by inflation, geopolitical tensions, and trade conflict while structural changes took place with a transition from old to new drivers of growth, the mushrooming emerging industries, and the reshaping of the global value chains.
基金Project(2008047B) supported by the Funds for Youth of Control South University of Forestry and Technology
文摘The effect of concrete creep on the pre-camber of a long-span pre-stressed concrete continuous rigid-frame bridge constructed by cantilever casting method was investigated.The difference of creep coefficients calculated with two Chinese codes was discussed.Based on the calculations,the pre-camber of a pre-stressed concrete continuous rigid-frame box bridge was computed for construction control purpose.The results show that the short-term creep coefficient and long-term creep coefficient calculated with the CC-1985 are larger than those calculated with the CC-2004,while the medium-term creep coefficient calculated with the CC-1985 is smaller than that calculated with the CC-2004.The difference of creep deformation calculated with these two codes is small,and the influences of concrete creep on the pre-camber for most of the segments are negligible.The deflections and stresses of the box girder measured during the construction stages agree very well with the predictions.
文摘Bangladeshi textile and garment sectors defied the global challenges over the last five years and continued to grow although the growth momentum was not so strong before the COVID-19 pandemic.Before the start of the pandemic,both the textile and garment sectors were growing at a higher rate because of rising demand from the international clothing retailers and brands because of two main reasons including the trade war between USA and China and competitive prices of locally made garment.
文摘The central bank data shows Bangladesh's import of RMG raw materials such as raw cotton,yarn,fabric and dyeing materials was US$7.92 billion in the first half of FY'24.The BGMEA reports Bangladesh's apparel exports are 71 per cent cotton-based.The country,however,meets 99 per cent of its cotton demand through imports.After Brazil,India is the second la rgest cotton supplier to Bangladesh and holds a 12 per cent market share,according to United States Department of Agriculture (USDA).
文摘With the current rapid development of urbanization in China,people's living standards have been greatly improved.In the context of such a development background,the requirements for road traffic are getting more stringent,especially for bridge projects.The arched continuous rigid-frame bridge was developed under this social background.The advantage of the bridge lies in the design of a bridge model that integrates various functions such as transportation,landscape,and sightseeing.Based on the above,this paper first refers to the case to analyze the design and construction strategy of the arched continuous rigid-frame bridge,in hope of providing a valuable reference for relevant personnel.
基金Doctoral Scientific Research Startup Foundation of Wuhan University of Technology,China(No.40120246)Hubei Key Laboratory of Roadway Bridge and Structure Engineering(Wuhan University of Technology)(No.DQJJ201505)
文摘In this study a 3D numerical analysis approach is developed to predict the ground vibration around rigid-frame viaducts induced by running high-speed trains. The train-bridge-ground interaction system is divided into two subsystems: the train-bridge interaction and the soil-structure interaction. First, the analytical program to simulate bridge vibration with consideration of train-bridge interaction is developed to obtain the vibration reaction forces at the pier bottoms. The high- speed train is described by a multi-DOFs vibration system and the rigid-frame viaduct is modeled with 3D beam elements. Second, applying these vibration reaction forces as input external excitations, the ground vibration is simulated by using a general-purpose program that includes soil-structure interaction effects. The validity of the analytical procedure is confirmed by comparing analytical and experimental results. The characteristics of high-speed train-induced vibrations, including the location of predominant vibration, are clarified. Based on this information a proposed vibration countermeasure using steel strut and new barrier is found effective in reducing train-induced vibrations and it satisfies environmental vibration requirements. The vibration screening efficiency is evaluated by reduction VAL based on 1/3 octave band spectral analysis.
基金Supported by the National Natural Science Foundation of china
文摘There are many accelerating convergence factors (ACFs) for limit periodic continued fraction K(an/1)(an→a≠0). In this paper, some characteristics and comparative theorems are ob tained on ACFs. Two results are given for most frequently used ACFs.
文摘A famous theorem of Szemer'edi asserts that any subset of integers with posi- tive upper density contains arbitrarily arithmetic progressions. Let Fq be a finite field with q elements and Fq((X^-1)) be the power field of formal series with coefficients lying in Fq. In this paper, we concern with the analogous Szemeredi problem for continued fractions of Laurent series: we will show that the set of points x ∈ Fq((X-1)) of whose sequence of degrees of partial quotients is strictly increasing and contain arbitrarily long arithmetic progressions is of Hausdorff dimension 1/2.
文摘The significant increase in the number of older adults in China,coupled with continuing industrialization and urbanization,has profound social and economic ramifications,including the evolution of major challenges to public health,elder care services,policy-making,and the nation’s healthcare system.While the unprecedented changes in political and economic structures have obviously increased China’s productivity and revenues,what is less well understood is how they
文摘We consider the block matrices and 3-dimensional graph manifolds associated with a special type of tree graphs. We demonstrate that the linking matrices of these graph manifolds coincide with the reduced matrices obtained from the Laplacian block matrices by means of Gauss partial diagonalization procedure described explicitly by W. Neumann. The linking matrix is an important topological invariant of a graph manifold which is possible to interpret as a matrix of coupling constants of gauge interaction in Kaluza-Klein approach, where 3-dimensional graph manifold plays the role of internal space in topological 7-dimensional BF theory. The Gauss-Neumann method gives us a simple algorithm to calculate the linking matrices of graph manifolds and thus the coupling constants matrices.
基金The NNSF(10171026 and 60473114)of Chinathe Research Funds(2005TD03) for Young Innovation Group,Education Department of Anhui Province.
文摘For a univariate function given by its Taylor series expansion, a continued fraction expansion can be obtained with the Viscovatov's algorithm, as the limiting value of a Thiele interpolating continued fraction or by means of the determinantal formulas for inverse and reciprocal differences with coincident data points. In this paper, both Viscovatov-like algorithms and Taylor-like expansions are incorporated to yield bivariate blending continued expansions which are computed as the limiting value of bivariate blending rational interpolants, which are constructed based on symmetric blending differences. Numerical examples are given to show the effectiveness of our methods.
基金This research was supported by National Natural Science Foundation of China(11771153,11801591,11971195,12171107)Guangdong Natural Science Foundation(2018B0303110005)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515010056)Kunkun Song would like to thank China Scholarship Council(CSC)for financial support(201806270091).
文摘Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=inf{s≥0:∑n≥1an^(-s)(x)<∞}.
文摘Modem and efficient methods focus on signal analysis and have drawn researchers' attention to it in recent years. These methods mainly include Continuous Wavelet and Wavelet Packet transforms. The main advantage of the application of these Wavelets is their capacity to analyze the signal position in different occasions and places. However, in sites with high frequencies its resolution becomes much more difficult. Wavelet packet transform is a more advanced form of continuous wavelets and can make a perfect level by level resolution for each signal. Although very few studies have been done in the field. In order to do this, in the present study, f^st there was an attempt to do a modal analysis on the structure by the ANSYS finite elements software, then using MATLAB, the wavelet was investigated through a continuous wavelet analysis. Finally the results were displayed in 2-D location-coefficient figures. In the second form, transient-dynamic analysis was done on the structure to find out the characteristics of the damage and the wavelet packet energy rate index was suggested. The results indicate that suggested index in the second form is both practical and applicable, and also this index is sensitive to the intensity of the damage.