To study the energy evolution and failure characteristics of saturated sandstone under unloading conditions,rock unloading tests under different stress paths were conducted.The energy evolution mechanism of the unload...To study the energy evolution and failure characteristics of saturated sandstone under unloading conditions,rock unloading tests under different stress paths were conducted.The energy evolution mechanism of the unloading failure of saturated sandstone was systematically explored from the perspectives of the stress path,the initial confining pressure,and the energy conversion rate.The results show that(1)before the peak stress,the elastic energy increases with an increase in deviatoric stress,while the dissipated energy slowly increases first.After the peak stress,the elastic energy decreases with the decrease of deviatoric stress,and the dissipated energy suddenly increases.The energy release intensity during rock failure is positively correlated with the axial stress.(2)When the initial confining pressure is below a certain threshold,the stress path is the main factor influencing the total energy difference.When the axial stress remains constant and the confining pressure is unloading,the total energy is more sensitive to changes in the confining pressure.When the axial stress remains constant,the compressive deformation ability of the rock cannot be significantly improved by the increase in the initial confining pressure.The initial confining pressure is positively correlated with the rock's energy storage limit.(3)The initial confining pressure increases the energy conversion rate of the rock;the initial confining pressure is positively correlated with the energy conversion rate;and the energy conversion rate has a high confining pressure effect.The increase in the axial stress has a much greater impact on the elastic energy than the confining pressure.(4)When the deviatoric stress is small,the confining pressure mainly plays a protective role.Compared with the case of triaxial compression paths,the rock damage is more severe under unloading paths,and compared with the case of constant axial stress,the rock damage is more severe under increasing axial stress.展开更多
In view of the series of problems found in the rural collective economic audit in Zhangdian District of Zibo City in the past five years,this study used empirical research methods to deeply analyze the current situati...In view of the series of problems found in the rural collective economic audit in Zhangdian District of Zibo City in the past five years,this study used empirical research methods to deeply analyze the current situation and existing problems of the village collective audit work.On this basis,typical cases were selected for in-depth analysis,the effects of different audit modes were compared,and the reliable paths to improve the efficiency of village collective audit were studied and considered.The results show that the social governance strategy plays a positive role in improving the efficiency of village collective audit.This study is expected to provide a reference for the improvement of village collective audit efficiency,and is of great significance to improve the village collective financial management and promote the improvement of the rural governance system.展开更多
The prioritization of financial infrastructure construction serves as a crucial guarantee for the high-quality development of small and micro enterprises.However,resolving the financing challenges of small and micro e...The prioritization of financial infrastructure construction serves as a crucial guarantee for the high-quality development of small and micro enterprises.However,resolving the financing challenges of small and micro enterprises is not a task to be accomplished overnight.It necessitates the establishment of a long-term mechanism,the acceleration of financial innovation,the gradual enhancement of the vitality of micro-entities,and the creation of a stable and healthy economic development environment.Therefore,the author first analyzes the current financing situation of small and micro enterprises,as well as the problems they face during the process of financial innovation enabling small and micro enterprises to access financing and solve their financing difficulties,such as insufficient technical support,an imperfect risk control system,incomplete information disclosure,and a lack of credit data.Subsequently,targeted paths for financial innovation are proposed,aiming to offer suggestions for solving the financing problems of small and micro enterprises.展开更多
With the deep integration of digitization and intelligence,smart teaching has become an important trend in the field of education.As a key link in cultivating professional nursing talents,higher nursing education face...With the deep integration of digitization and intelligence,smart teaching has become an important trend in the field of education.As a key link in cultivating professional nursing talents,higher nursing education faces new opportunities and challenges in the context of smart teaching.This article deeply explores the necessity of innovating higher nursing education in the context of smart teaching,analyzes the current problems in higher nursing education,and proposes specific innovation paths from the aspects of teaching philosophy,teaching mode,teaching resources,teacher team building,and evaluation system.The aim is to improve the quality of higher nursing education and provide theoretical references for cultivating high-quality nursing talents that meet the needs of smart healthcare.展开更多
Outer-independent Roman domination on graphs originates from the defensive strategy of Ancient Rome,which is that if any city without an army is attacked,a neighboring city with two armies could mobilize an army to su...Outer-independent Roman domination on graphs originates from the defensive strategy of Ancient Rome,which is that if any city without an army is attacked,a neighboring city with two armies could mobilize an army to support it and any two cities that have no army cannot be adjacent.The outer-independent Roman domination on graphs is an attractive topic in graph theory,and the definition is described as follows.Given a graph G=(V,E),a function f:V(G)→{0,1,2}is an outer-independent Roman dominating function(OIRDF)if f satisfies that every vertex v∈V with f(v)=0 has at least one adjacent vertex u∈N(v)with f(u)=2,where N(v)is the open neighborhood of v,and the set V0={v|f(v)=0}is an independent set.The weight of an OIRDF f is w(f)=∑_(v∈V)f(v).The value of minf w(f)is the outerindependent Roman domination number of G,denoted asγoiR(G).This paper is devoted to the study of the outer-independent Roman domination number of the Cartesian product of paths P_(n)□P_(m).With the help of computer,we find some recursive OIRDFs and then we present an upper bound ofγoiR(P_(n)□P_(m)).Furthermore,we prove the lower bound ofγoiR(P_(n)□P_(m))(n≤3)is equal to the upper bound.Hence,we achieve the exact value ofγoiR(P_(n)□P_(m))for n≤3 and the upper bound ofγoiR(P_(n)□P_(m))for n≥4.展开更多
With the rapid development of private higher education,the construction of counselor teams in private universities has become increasingly important.This paper focuses on outstanding counselors in private universities...With the rapid development of private higher education,the construction of counselor teams in private universities has become increasingly important.This paper focuses on outstanding counselors in private universities,delving into their growth patterns and proposing targeted training paths based on this analysis.By reviewing relevant theories and analyzing case studies of excellent counselors,it is found that outstanding counselors in private universities exhibit stage-specific characteristics during their development,influenced by personal traits,school environment,career progression,and other factors.In terms of training approaches,efforts should be made to improve selection mechanisms,strengthen training systems,provide career development support,and create a positive work atmosphere,all aimed at enhancing the overall quality of the counselor team in private universities and better serving student growth and institutional development.展开更多
While Western modernization is often regarded as a dominant model of linear progress,existing theories frequently overlook the diversity of modernization paths and the underlying commonalities shared across them.The r...While Western modernization is often regarded as a dominant model of linear progress,existing theories frequently overlook the diversity of modernization paths and the underlying commonalities shared across them.The rise of alternative models,exemplified by Chinese path to modernization,underscores the potential for multiple trajectories of modernization and reveals three core elements that define these paths:building consensus on development,generating momentum for growth,and enhancing resilience to challenges.The success of Chinese path to modernization can be attributed to several key factors:the establishment of a national development consensus driven by the leadership of the Communist Party of China;the creation of development momentum through endogenous growth,optimal resource allocation,and a sustained commitment to reform and opening-up;and the strengthening of resilience via economic diversification,gradual reforms,and robust risk management strategies.In contrast,African nations present a distinct mix of traditional consensus governance and modern democratic practices,while actively engaging in development-security-governance nexus management and refining early warning and crisis management systems.These countries are exploring their own paths to modernization,informed by their unique socio-political contexts.Despite many differences in national conditions,exchanges of experiences between China and African countries-focused on development consensus,momentum,and resilience-can break the myth that“modernization equals Westernization”.Such exchanges can empower developing nations to pursue their own,independent,and context-specific routes toward modernization.展开更多
Synergistic reduction of carbon emissions and air pollution is the core means to address the two major strategic tasks of fundamentally improving the ecological environment and the‘Dual-carbon target’.The issue of s...Synergistic reduction of carbon emissions and air pollution is the core means to address the two major strategic tasks of fundamentally improving the ecological environment and the‘Dual-carbon target’.The issue of synergistic reduction at the provincial level needs to be addressed as a matter of urgency.Taking Henan Province,the largest economy in central China,as an example,this study uses environmentally extended input-output analysis and structural path analysis to identify the key sectors that contribute to CO_(2),SO_(2),and total particulate matter(TPM)emissions,and to sort out key emission pathways(e.g.,Final Demand→Sector…).The results indicate that S2(Mining of Fossil Energy),S10(Nonmetal Mineral Products),S11(Metal Smelting),S13(Power and Heat)and S17(Transportation)are mainly responsible for CO_(2),SO_(2),and TPM direct emissions on the production side,while S16(Construction),S12(Equipment)and S18(Services)account for more than 45%of CO_(2),SO_(2),and TPM embodied emissions on the consumption side.32 shared emission pathways are extracted from the top 100 pathways for CO_(2),SO_(2),and TPM emissions,which account for 27%-51%of total emissions in Henan Province.P9(Export→Nonmetal Mineral Products),P10(Export→Metal Smelting)and P21(Gross Capital Formation→Construction→Nonmetal Mineral Products)are the leading paths responsible for embodied emissions.The research results provide the foundation and guidance for well-designed mitigation policies,as well as a reference for better synergistic control in provinces facing similar situations.展开更多
During the development blasting of circular tunnels, the detonation of multiple blastholes arranged onconcentric circles induces a complex dynamic response in the surrounding rocks. This process involvesmultiple blast...During the development blasting of circular tunnels, the detonation of multiple blastholes arranged onconcentric circles induces a complex dynamic response in the surrounding rocks. This process involvesmultiple blast loadings, static stress unloadings, and stress redistributions. In this study, the dynamicstresses of the surrounding rocks during development blasting, considering multiple blasting-unloadingstages with exponential paths and triangular paths (linear simplified paths of exponential paths), aresolved based on the dynamic theory and the Fourier transform method. Then, a corresponding discreteelement model is established using particle flow code (PFC). The multiple-stage dynamic stress andfracture distribution under different in situ stress levels and lateral coefficients are investigated. Theoreticalresults indicate that the peak compressive stresses in the surrounding rocks induced by bothtriangular and exponential paths are equal, while the triangular path generates greater additional dynamictensile stresses, particularly in the circumferential direction, compared to the exponential path.Numerical results show that the exponential path causes less dynamic circumferential tensile damageand forms fewer radial fractures than the triangular path in the first few blast stages;conversely, itexacerbates the damage and instability in the final blasting-unloading stage and forms more circumferentialfractures. Furthermore, the in situ stress determines which of the two opposite effects isdominant. Therefore, when using overly simplified triangular paths to evaluate the stability of surroundingrocks, potential overestimation or underestimation caused by different failure mechanismsshould be considered. Specifically, under high horizontal and vertical stresses, the static stress redistributionwith layer-by-layer blasting suppresses dynamic circumferential tensile and radial compressivedamage. The damage evolution of surrounding rocks in multi-stage blasting under different in situstresses is summarized and classified according to the damage mechanism and characteristics, which canguide blasting and support design.展开更多
The Wiener index of a graph is defined to be the sum of the distances of all pairs of vertices in the graph.The kth power G^(k) of a graph G is the graph on V(G)and two vertices are adjacent if and only if their dista...The Wiener index of a graph is defined to be the sum of the distances of all pairs of vertices in the graph.The kth power G^(k) of a graph G is the graph on V(G)and two vertices are adjacent if and only if their distance in G is less or equal to k.In this paper,we computed the Wiener index of the kth power of paths and cycles for any k≥2.展开更多
Rapidly-exploring Random Tree(RRT)and its variants have become foundational in path-planning research,yet in complex three-dimensional off-road environments their uniform blind sampling and limited safety guarantees l...Rapidly-exploring Random Tree(RRT)and its variants have become foundational in path-planning research,yet in complex three-dimensional off-road environments their uniform blind sampling and limited safety guarantees lead to slow convergence and force an unfavorable trade-off between path quality and traversal safety.To address these challenges,we introduce HS-APF-RRT*,a novel algorithm that fuses layered sampling,an enhanced Artificial Potential Field(APF),and a dynamic neighborhood-expansion mechanism.First,the workspace is hierarchically partitioned into macro,meso,and micro sampling layers,progressively biasing random samples toward safer,lower-energy regions.Second,we augment the traditional APF by incorporating a slope-dependent repulsive term,enabling stronger avoidance of steep obstacles.Third,a dynamic expansion strategy adaptively switches between 8 and 16 connected neighborhoods based on local obstacle density,striking an effective balance between search efficiency and collision-avoidance precision.In simulated off-road scenarios,HS-APF-RRT*is benchmarked against RRT*,GoalBiased RRT*,and APF-RRT*,and demonstrates significantly faster convergence,lower path-energy consumption,and enhanced safety margins.展开更多
Based on energy theory and tests of rocks with initial confining pressures of 10, 20 and 30 MPa under different unloading paths, the processes of strain energy conversion were investigated. The absorbing strain energy...Based on energy theory and tests of rocks with initial confining pressures of 10, 20 and 30 MPa under different unloading paths, the processes of strain energy conversion were investigated. The absorbing strain energy for axial compression, the dissipating strain energy for plastic deformation and cracks propagation, the expending strain energy for circumferential deformation, and the storing and releasing elastic strain energy were considered. Unloading paths included the condition of fixing axial pressure and unloading axial pressure, increasing axial pressure and unloading confining pressure, as well as unloading axial pressure and confining pressure simultaneously. Results show that expending strain energy for circumferential deformation has mainly evolved from absorbing strain energy for axial compression in three unloading paths during unloading processes. Dissipating strain energy is significantly increased only near the peak point. The effect of initial confining pressure on strain energy is significantly higher than that of unloading path. The strain energy is linearly increased with increasing initial confining pressure. The unloading path and initial confining pressure also have great influence on the energy dissipation. The conversion rate of strain energy in three paths is increased with increasing initial confining pressure, and the effect of initial confining pressure on conversion rate of strain energy is related with the unloading paths.展开更多
The main factors affecting seismic exploration is the propagation velocity of seismic waves in the medium. In the past, during marine seismic data processing, the propagation velocity of sea water was generally taken ...The main factors affecting seismic exploration is the propagation velocity of seismic waves in the medium. In the past, during marine seismic data processing, the propagation velocity of sea water was generally taken as a constant 1500 m/s. However, for deep water exploration, the sound velocity varies with the season, time, location, water depth, ocean currents, and etc.. It also results in a layered velocity distribution, so there is a difference of seismic traveltime, ray paths, and amplitude, which affect the migration imaging results if sea water propagation velocity is still taken as constant for the propagation wavefield. In this paper, we will start from an empirical equation of seismic wave velocity in seawater with changes of temperature, salinity, and depth, consider the variation of their values, build a seawater velocity model, and quantitatively analyze the impact of seawater velocity variation on seismic traveltime, ray paths, and amplitude in the seawater velocity model.展开更多
Understanding of hydrological processes in caves is important to help us interpret paleoclimate records from speleothems. In this study, we integrated hydrogeological and hydrogeochemical properties to characterize th...Understanding of hydrological processes in caves is important to help us interpret paleoclimate records from speleothems. In this study, we integrated hydrogeological and hydrogeochemical properties to characterize the hydraulic behavior of karst waters in the Heshang Cave, Central China. Using geological and topographical analyses, we identified regional watershed boundaries and hydrogeological connections that were controlled by anticlinal geometry and faults. Water samples were collected from the Heshang Cave and potential recharge sites. Geochemical data of c（Sr^2＋）/c（Ca^2＋） and c（Mg^2＋）/c（Ca^2＋） ratios suggest that the drainage system in Heshang Cave consists of two flow paths. For vadose waters, including drip water and rimstone pool water, c（Sr^2＋）/c（Ca^2＋） ratio ranges from 0.000 6 to 0.001 1, and c（Mg^2＋）/c（Ca^2＋） ratio ranges from 0.97 to 1.1, indicating that recharge was mainly from rainfall infiltration through the overlying Cambrian dolomite stratum. In contrast, slope current and underground river waters have higher c（Sr^2＋）/c（Ca^2＋） ratios （values from 0.002 2 to 0.002 8）, and lower c（Mg2＋）/c（Ca^2＋） ratios （values from 0.50 to 0.64）. These waters show homogeneous isotopic composition （δ^18O： -7.15‰- -6.95‰; δD： -52.73‰- -51.31‰）, implying recharge of allogeneic water from the Xiaocr River via karst conduits that pass through Ordovician limestone and Cambrian dolomite stratum.展开更多
Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via ...Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ18O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the δ18O in the rainy season smaller than in,the dry season. The δ18O values in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ18O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ18O in precipitation reaches its minimum at Urumqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ18O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ18O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ18O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season, but δ18O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ18O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ18O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.展开更多
The current research of the 5-axis tool positioning algorithm mainly focuses on searching the local optimal tool position without gouging and interference at a cutter contact（CC） point,while not considering the smoo...The current research of the 5-axis tool positioning algorithm mainly focuses on searching the local optimal tool position without gouging and interference at a cutter contact（CC） point,while not considering the smoothness and continuity of a whole tool path.When the surface curvature varies significantly,a local abrupt change of tool paths will happen.The abrupt change has a great influence on surface machining quality.In order to keep generated tool paths smooth and continuous,a five-axis tool positioning algorithm based on smooth tool paths is presented.Firstly,the inclination angle,the tilt angle and offset distance of the tool at a CC point are used as design variables,and the machining strip width is used as an objective function,an optimization model of a local tool positioning algorithm is thus established.Then,a vector equation of tool path is derived by using the above optimization model.By analyzing the equation,the main factors affecting the tool path quality are obtained.Finally,a new tool position optimization model is established,and the detailed process of tool position optimization is also given.An experiment is conducted to machine an aircraft turbine blade by using the proposed algorithm on a 5-axis blade grinding machine,and the machined blade surface is measured with a coordinate measuring machine（CMM）.Experimental and measured results show that the proposed algorithm can ensure tool paths are smooth and continuous,improve the tool path quality,avoid the local abrupt change of tool paths,and enhance machining quality and machining efficiency of sculptured surfaces.展开更多
基金Anhui Natural Science Foundation Youth Program,Grant/Award Number:2208085QE142National Natural Science Foundations of China,Grant/Award Numbers:52004003,52304073Opening Foundation of Anhui Province Key Laboratory of Building Structure and Underground Engineering,Grant/Award Number:KLBSUE-2022-04。
文摘To study the energy evolution and failure characteristics of saturated sandstone under unloading conditions,rock unloading tests under different stress paths were conducted.The energy evolution mechanism of the unloading failure of saturated sandstone was systematically explored from the perspectives of the stress path,the initial confining pressure,and the energy conversion rate.The results show that(1)before the peak stress,the elastic energy increases with an increase in deviatoric stress,while the dissipated energy slowly increases first.After the peak stress,the elastic energy decreases with the decrease of deviatoric stress,and the dissipated energy suddenly increases.The energy release intensity during rock failure is positively correlated with the axial stress.(2)When the initial confining pressure is below a certain threshold,the stress path is the main factor influencing the total energy difference.When the axial stress remains constant and the confining pressure is unloading,the total energy is more sensitive to changes in the confining pressure.When the axial stress remains constant,the compressive deformation ability of the rock cannot be significantly improved by the increase in the initial confining pressure.The initial confining pressure is positively correlated with the rock's energy storage limit.(3)The initial confining pressure increases the energy conversion rate of the rock;the initial confining pressure is positively correlated with the energy conversion rate;and the energy conversion rate has a high confining pressure effect.The increase in the axial stress has a much greater impact on the elastic energy than the confining pressure.(4)When the deviatoric stress is small,the confining pressure mainly plays a protective role.Compared with the case of triaxial compression paths,the rock damage is more severe under unloading paths,and compared with the case of constant axial stress,the rock damage is more severe under increasing axial stress.
文摘In view of the series of problems found in the rural collective economic audit in Zhangdian District of Zibo City in the past five years,this study used empirical research methods to deeply analyze the current situation and existing problems of the village collective audit work.On this basis,typical cases were selected for in-depth analysis,the effects of different audit modes were compared,and the reliable paths to improve the efficiency of village collective audit were studied and considered.The results show that the social governance strategy plays a positive role in improving the efficiency of village collective audit.This study is expected to provide a reference for the improvement of village collective audit efficiency,and is of great significance to improve the village collective financial management and promote the improvement of the rural governance system.
文摘The prioritization of financial infrastructure construction serves as a crucial guarantee for the high-quality development of small and micro enterprises.However,resolving the financing challenges of small and micro enterprises is not a task to be accomplished overnight.It necessitates the establishment of a long-term mechanism,the acceleration of financial innovation,the gradual enhancement of the vitality of micro-entities,and the creation of a stable and healthy economic development environment.Therefore,the author first analyzes the current financing situation of small and micro enterprises,as well as the problems they face during the process of financial innovation enabling small and micro enterprises to access financing and solve their financing difficulties,such as insufficient technical support,an imperfect risk control system,incomplete information disclosure,and a lack of credit data.Subsequently,targeted paths for financial innovation are proposed,aiming to offer suggestions for solving the financing problems of small and micro enterprises.
文摘With the deep integration of digitization and intelligence,smart teaching has become an important trend in the field of education.As a key link in cultivating professional nursing talents,higher nursing education faces new opportunities and challenges in the context of smart teaching.This article deeply explores the necessity of innovating higher nursing education in the context of smart teaching,analyzes the current problems in higher nursing education,and proposes specific innovation paths from the aspects of teaching philosophy,teaching mode,teaching resources,teacher team building,and evaluation system.The aim is to improve the quality of higher nursing education and provide theoretical references for cultivating high-quality nursing talents that meet the needs of smart healthcare.
文摘Outer-independent Roman domination on graphs originates from the defensive strategy of Ancient Rome,which is that if any city without an army is attacked,a neighboring city with two armies could mobilize an army to support it and any two cities that have no army cannot be adjacent.The outer-independent Roman domination on graphs is an attractive topic in graph theory,and the definition is described as follows.Given a graph G=(V,E),a function f:V(G)→{0,1,2}is an outer-independent Roman dominating function(OIRDF)if f satisfies that every vertex v∈V with f(v)=0 has at least one adjacent vertex u∈N(v)with f(u)=2,where N(v)is the open neighborhood of v,and the set V0={v|f(v)=0}is an independent set.The weight of an OIRDF f is w(f)=∑_(v∈V)f(v).The value of minf w(f)is the outerindependent Roman domination number of G,denoted asγoiR(G).This paper is devoted to the study of the outer-independent Roman domination number of the Cartesian product of paths P_(n)□P_(m).With the help of computer,we find some recursive OIRDFs and then we present an upper bound ofγoiR(P_(n)□P_(m)).Furthermore,we prove the lower bound ofγoiR(P_(n)□P_(m))(n≤3)is equal to the upper bound.Hence,we achieve the exact value ofγoiR(P_(n)□P_(m))for n≤3 and the upper bound ofγoiR(P_(n)□P_(m))for n≥4.
基金The Second Batch of Comprehensive Reform and Quality Construction Projects of Party Building and Ideological and Political Education in 2024“Research on the Growth Patterns and Training Path of Excellent Counselors in Private Colleges”(HKDS2024YB11)。
文摘With the rapid development of private higher education,the construction of counselor teams in private universities has become increasingly important.This paper focuses on outstanding counselors in private universities,delving into their growth patterns and proposing targeted training paths based on this analysis.By reviewing relevant theories and analyzing case studies of excellent counselors,it is found that outstanding counselors in private universities exhibit stage-specific characteristics during their development,influenced by personal traits,school environment,career progression,and other factors.In terms of training approaches,efforts should be made to improve selection mechanisms,strengthen training systems,provide career development support,and create a positive work atmosphere,all aimed at enhancing the overall quality of the counselor team in private universities and better serving student growth and institutional development.
基金This article forms part of the 2021 Major Bidding Project under the Special Research Program on Significant Historical Issues,supported by the Chinese Academy of History and funded by the National Social Science Foundation of China:“General History of Africa(Multi-Volume Edition)”(Grant No.LSYZD21022).
文摘While Western modernization is often regarded as a dominant model of linear progress,existing theories frequently overlook the diversity of modernization paths and the underlying commonalities shared across them.The rise of alternative models,exemplified by Chinese path to modernization,underscores the potential for multiple trajectories of modernization and reveals three core elements that define these paths:building consensus on development,generating momentum for growth,and enhancing resilience to challenges.The success of Chinese path to modernization can be attributed to several key factors:the establishment of a national development consensus driven by the leadership of the Communist Party of China;the creation of development momentum through endogenous growth,optimal resource allocation,and a sustained commitment to reform and opening-up;and the strengthening of resilience via economic diversification,gradual reforms,and robust risk management strategies.In contrast,African nations present a distinct mix of traditional consensus governance and modern democratic practices,while actively engaging in development-security-governance nexus management and refining early warning and crisis management systems.These countries are exploring their own paths to modernization,informed by their unique socio-political contexts.Despite many differences in national conditions,exchanges of experiences between China and African countries-focused on development consensus,momentum,and resilience-can break the myth that“modernization equals Westernization”.Such exchanges can empower developing nations to pursue their own,independent,and context-specific routes toward modernization.
基金supported by the National Natural Science Foundation of China(No.42001246)the Energy Foundation(No.G-2209-34120).
文摘Synergistic reduction of carbon emissions and air pollution is the core means to address the two major strategic tasks of fundamentally improving the ecological environment and the‘Dual-carbon target’.The issue of synergistic reduction at the provincial level needs to be addressed as a matter of urgency.Taking Henan Province,the largest economy in central China,as an example,this study uses environmentally extended input-output analysis and structural path analysis to identify the key sectors that contribute to CO_(2),SO_(2),and total particulate matter(TPM)emissions,and to sort out key emission pathways(e.g.,Final Demand→Sector…).The results indicate that S2(Mining of Fossil Energy),S10(Nonmetal Mineral Products),S11(Metal Smelting),S13(Power and Heat)and S17(Transportation)are mainly responsible for CO_(2),SO_(2),and TPM direct emissions on the production side,while S16(Construction),S12(Equipment)and S18(Services)account for more than 45%of CO_(2),SO_(2),and TPM embodied emissions on the consumption side.32 shared emission pathways are extracted from the top 100 pathways for CO_(2),SO_(2),and TPM emissions,which account for 27%-51%of total emissions in Henan Province.P9(Export→Nonmetal Mineral Products),P10(Export→Metal Smelting)and P21(Gross Capital Formation→Construction→Nonmetal Mineral Products)are the leading paths responsible for embodied emissions.The research results provide the foundation and guidance for well-designed mitigation policies,as well as a reference for better synergistic control in provinces facing similar situations.
基金supported by the National Natural Science Foundation of China(Grant Nos.51927808 and 41630642)the Postgraduate Innovation Fund Project of Hunan Province(Grant No.CX20200242).
文摘During the development blasting of circular tunnels, the detonation of multiple blastholes arranged onconcentric circles induces a complex dynamic response in the surrounding rocks. This process involvesmultiple blast loadings, static stress unloadings, and stress redistributions. In this study, the dynamicstresses of the surrounding rocks during development blasting, considering multiple blasting-unloadingstages with exponential paths and triangular paths (linear simplified paths of exponential paths), aresolved based on the dynamic theory and the Fourier transform method. Then, a corresponding discreteelement model is established using particle flow code (PFC). The multiple-stage dynamic stress andfracture distribution under different in situ stress levels and lateral coefficients are investigated. Theoreticalresults indicate that the peak compressive stresses in the surrounding rocks induced by bothtriangular and exponential paths are equal, while the triangular path generates greater additional dynamictensile stresses, particularly in the circumferential direction, compared to the exponential path.Numerical results show that the exponential path causes less dynamic circumferential tensile damageand forms fewer radial fractures than the triangular path in the first few blast stages;conversely, itexacerbates the damage and instability in the final blasting-unloading stage and forms more circumferentialfractures. Furthermore, the in situ stress determines which of the two opposite effects isdominant. Therefore, when using overly simplified triangular paths to evaluate the stability of surroundingrocks, potential overestimation or underestimation caused by different failure mechanismsshould be considered. Specifically, under high horizontal and vertical stresses, the static stress redistributionwith layer-by-layer blasting suppresses dynamic circumferential tensile and radial compressivedamage. The damage evolution of surrounding rocks in multi-stage blasting under different in situstresses is summarized and classified according to the damage mechanism and characteristics, which canguide blasting and support design.
基金Supported by National Natural Science Foundation of China(Grant No.12201471)the Special Foundation in Key Fields for Universities of Guangdong Province(Grant No.2022ZDZX1034).
文摘The Wiener index of a graph is defined to be the sum of the distances of all pairs of vertices in the graph.The kth power G^(k) of a graph G is the graph on V(G)and two vertices are adjacent if and only if their distance in G is less or equal to k.In this paper,we computed the Wiener index of the kth power of paths and cycles for any k≥2.
基金supported in part by 14th Five Year National Key R&D Program Project(Project Number:2023YFB3211001)the National Natural Science Foundation of China(62273339,U24A201397).
文摘Rapidly-exploring Random Tree(RRT)and its variants have become foundational in path-planning research,yet in complex three-dimensional off-road environments their uniform blind sampling and limited safety guarantees lead to slow convergence and force an unfavorable trade-off between path quality and traversal safety.To address these challenges,we introduce HS-APF-RRT*,a novel algorithm that fuses layered sampling,an enhanced Artificial Potential Field(APF),and a dynamic neighborhood-expansion mechanism.First,the workspace is hierarchically partitioned into macro,meso,and micro sampling layers,progressively biasing random samples toward safer,lower-energy regions.Second,we augment the traditional APF by incorporating a slope-dependent repulsive term,enabling stronger avoidance of steep obstacles.Third,a dynamic expansion strategy adaptively switches between 8 and 16 connected neighborhoods based on local obstacle density,striking an effective balance between search efficiency and collision-avoidance precision.In simulated off-road scenarios,HS-APF-RRT*is benchmarked against RRT*,GoalBiased RRT*,and APF-RRT*,and demonstrates significantly faster convergence,lower path-energy consumption,and enhanced safety margins.
基金Project(51324744)supported by the National Natural Science Foundation of ChinaProject(71380100006)supported by the Innovation Foundation of Doctoral Student in Hunan Province,China
文摘Based on energy theory and tests of rocks with initial confining pressures of 10, 20 and 30 MPa under different unloading paths, the processes of strain energy conversion were investigated. The absorbing strain energy for axial compression, the dissipating strain energy for plastic deformation and cracks propagation, the expending strain energy for circumferential deformation, and the storing and releasing elastic strain energy were considered. Unloading paths included the condition of fixing axial pressure and unloading axial pressure, increasing axial pressure and unloading confining pressure, as well as unloading axial pressure and confining pressure simultaneously. Results show that expending strain energy for circumferential deformation has mainly evolved from absorbing strain energy for axial compression in three unloading paths during unloading processes. Dissipating strain energy is significantly increased only near the peak point. The effect of initial confining pressure on strain energy is significantly higher than that of unloading path. The strain energy is linearly increased with increasing initial confining pressure. The unloading path and initial confining pressure also have great influence on the energy dissipation. The conversion rate of strain energy in three paths is increased with increasing initial confining pressure, and the effect of initial confining pressure on conversion rate of strain energy is related with the unloading paths.
基金supported by the Major Projects of National Science and Technology Sub-topics(2011ZX05025-001-05)
文摘The main factors affecting seismic exploration is the propagation velocity of seismic waves in the medium. In the past, during marine seismic data processing, the propagation velocity of sea water was generally taken as a constant 1500 m/s. However, for deep water exploration, the sound velocity varies with the season, time, location, water depth, ocean currents, and etc.. It also results in a layered velocity distribution, so there is a difference of seismic traveltime, ray paths, and amplitude, which affect the migration imaging results if sea water propagation velocity is still taken as constant for the propagation wavefield. In this paper, we will start from an empirical equation of seismic wave velocity in seawater with changes of temperature, salinity, and depth, consider the variation of their values, build a seawater velocity model, and quantitatively analyze the impact of seawater velocity variation on seismic traveltime, ray paths, and amplitude in the seawater velocity model.
基金supported by the National Natural Science Foundation of China (Nos.91125009,91325101,and 06013024)
文摘Understanding of hydrological processes in caves is important to help us interpret paleoclimate records from speleothems. In this study, we integrated hydrogeological and hydrogeochemical properties to characterize the hydraulic behavior of karst waters in the Heshang Cave, Central China. Using geological and topographical analyses, we identified regional watershed boundaries and hydrogeological connections that were controlled by anticlinal geometry and faults. Water samples were collected from the Heshang Cave and potential recharge sites. Geochemical data of c（Sr^2＋）/c（Ca^2＋） and c（Mg^2＋）/c（Ca^2＋） ratios suggest that the drainage system in Heshang Cave consists of two flow paths. For vadose waters, including drip water and rimstone pool water, c（Sr^2＋）/c（Ca^2＋） ratio ranges from 0.000 6 to 0.001 1, and c（Mg^2＋）/c（Ca^2＋） ratio ranges from 0.97 to 1.1, indicating that recharge was mainly from rainfall infiltration through the overlying Cambrian dolomite stratum. In contrast, slope current and underground river waters have higher c（Sr^2＋）/c（Ca^2＋） ratios （values from 0.002 2 to 0.002 8）, and lower c（Mg2＋）/c（Ca^2＋） ratios （values from 0.50 to 0.64）. These waters show homogeneous isotopic composition （δ^18O： -7.15‰- -6.95‰; δD： -52.73‰- -51.31‰）, implying recharge of allogeneic water from the Xiaocr River via karst conduits that pass through Ordovician limestone and Cambrian dolomite stratum.
基金This work was supported by the National High Technology Research and Development Program of China(863 Program,Grant No.2002AA135360)the National Natural Science Foundation of China(Grant Nos.40271025 and 90302006).
文摘Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ18O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the δ18O in the rainy season smaller than in,the dry season. The δ18O values in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ18O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ18O in precipitation reaches its minimum at Urumqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ18O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ18O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ18O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season, but δ18O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ18O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ18O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.
基金supported by National Natural Science Foundation of China (Grant No. 50875012)National Hi-tech Research and Development Program of China (863 Program, Grant No. 2008AA04Z124)+1 种基金National Science and Technology Major Project of China (Grant No. 2009ZX04001-141)Joint Construction Project of Beijing Municipal Commission of Education of China
文摘The current research of the 5-axis tool positioning algorithm mainly focuses on searching the local optimal tool position without gouging and interference at a cutter contact（CC） point,while not considering the smoothness and continuity of a whole tool path.When the surface curvature varies significantly,a local abrupt change of tool paths will happen.The abrupt change has a great influence on surface machining quality.In order to keep generated tool paths smooth and continuous,a five-axis tool positioning algorithm based on smooth tool paths is presented.Firstly,the inclination angle,the tilt angle and offset distance of the tool at a CC point are used as design variables,and the machining strip width is used as an objective function,an optimization model of a local tool positioning algorithm is thus established.Then,a vector equation of tool path is derived by using the above optimization model.By analyzing the equation,the main factors affecting the tool path quality are obtained.Finally,a new tool position optimization model is established,and the detailed process of tool position optimization is also given.An experiment is conducted to machine an aircraft turbine blade by using the proposed algorithm on a 5-axis blade grinding machine,and the machined blade surface is measured with a coordinate measuring machine（CMM）.Experimental and measured results show that the proposed algorithm can ensure tool paths are smooth and continuous,improve the tool path quality,avoid the local abrupt change of tool paths,and enhance machining quality and machining efficiency of sculptured surfaces.
