The dynamic load distribution within in-service axlebox bearings of high-speed trains is crucial for the fatigue reliability assessment and forward design of axlebox bearings. This paper presents an in situ measuremen...The dynamic load distribution within in-service axlebox bearings of high-speed trains is crucial for the fatigue reliability assessment and forward design of axlebox bearings. This paper presents an in situ measurement of the dynamic load distribution in the four rows of two axlebox bearings on a bogie wheelset of a high-speed train under polygonal wheel–rail excitation. The measurement employed an improved strain-based method to measure the dynamic radial load distribution of roller bearings. The four rows of two axlebox bearings on a wheelset exhibited different ranges of loaded zones and different means of distributed loads. Besides, the mean value and standard deviation of measured roller–raceway contact loads showed non-monotonic variations with the frequency of wheel–rail excitation. The fatigue life of the four bearing rows under polygonal wheel–rail excitation was quantitatively predicted by compiling the measured roller–raceway contact load spectra of the most loaded position and considering the load spectra as input.展开更多
Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai...Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges.展开更多
Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pP...Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison.展开更多
Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stre...Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.展开更多
The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a pati...The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a patient's health status directly from their perspective,encompassing various domains such as symptom severity,functional status,and overall quality of life.By integrating PROMs into routine clinical practice and research,healthcare providers can achieve a more nuanced understanding of patient experiences and tailor treatments accordingly.The deployment of PROMs supports dynamic patient-provider interactions,fostering better patient engagement and adherence to tre-atment plans.Moreover,PROMs are pivotal in clinical settings for monitoring disease progression and treatment efficacy,particularly in chronic and mental health conditions.However,challenges in implementing PROMs include data collection and management,integration into existing health systems,and acceptance by patients and providers.Overcoming these barriers necessitates technological advancements,policy development,and continuous education to enhance the acceptability and effectiveness of PROMs.The paper concludes with recommendations for future research and policy-making aimed at optimizing the use and impact of PROMs across healthcare settings.展开更多
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ...In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice.展开更多
Based on two dimensions of supply and demand,we use six indicators to establish a rural inclusive financial development index and evaluate the development of China's rural inclusive finance. We use spatial panel d...Based on two dimensions of supply and demand,we use six indicators to establish a rural inclusive financial development index and evaluate the development of China's rural inclusive finance. We use spatial panel data model to examine the relationship between financial inclusion and rural poverty. Results show that:( i) both the rural inclusive finance and rural residents' per capita consumption present spatial clustering feature and show significant spatial correlation;( ii) the development of rural inclusive finance has significant spatial effect on poverty alleviation along time and space dimensions. In this study,the paper puts forward policy recommendations on strengthening the rural financial resources flow and constructing diversified rural inclusive financial system.展开更多
The tooth surface shape of hypoid gear is very complicated, and tooth surface accuracy of hypoid gear can be measured by using the latticed measurement and scanning measurement. Advantages and disadvantages of the two...The tooth surface shape of hypoid gear is very complicated, and tooth surface accuracy of hypoid gear can be measured by using the latticed measurement and scanning measurement. Advantages and disadvantages of the two measurement patterns are compared and application of their measurement data on hypoid gear's quality management is analyzed. How to use these measurement data to simulate the dynamical performance of hypoid gear is researched, and the intelligent predicton of the dynamical performance indexes of contact spot, root stress, vibration exciting forces and load distribution and hertz contact stress on the tooth surface are carried out. This research work has an important guiding sense to design and ma- chine hypoid gear with low vibration and noise.展开更多
Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general c...Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion.展开更多
An infrared colorimetric radiation thermometrical system was established based on the theory of optical radiation. The dynamic temperature history of fuel air explosive (FAE) was measured to obtain the temperature res...An infrared colorimetric radiation thermometrical system was established based on the theory of optical radiation. The dynamic temperature history of fuel air explosive (FAE) was measured to obtain the temperature responses of primary initiation FAE and secondary initiation FAE in real time. And the characteristics of their temperature history curves were compared and analyzed. The results show that the primary initiation FAE has higher explosion temperature and longer duration compared to the secondary initiation FAE.展开更多
Poverty eradication is an important goal of African social development.China has always attached great importance to exchanges and cooperation with African countries in the field of poverty reduction and with the deep...Poverty eradication is an important goal of African social development.China has always attached great importance to exchanges and cooperation with African countries in the field of poverty reduction and with the deepening of the practice and understanding of China-Africa anti-poverty cooperation,industrial-capacity cooperation has become a new theme of poverty reduction and development in China-Africa cooperation at the 2016 Forum on China Africa Cooperation(FOCAC)—Africa-China Poverty Reduction and Development Conference.Through combing and analysis of relevant literature and data,we found that China-Africa industrial-capacity cooperation,which is based on infrastructure construction,industrial park construction and trade exchanges,has played an important role in poverty reduction and development in African countries by facilitating industrialization and agricultural modernization,enhancing endogenous motivation for poverty alleviation,and improving the sustainable livelihood of poor people.At present,in the practice of anti-poverty industrial-capacity cooperation between China and Africa,there are still difficulties such as weak anti-poverty foundation and cooperation paths yet to be optimized.Meanwhile,it is also faced with a series of risks and challenges such as intensified international competition.In order to improve the cooperation between China and Africa,promote anti-poverty benefits,optimize the implementation paths,and better solve the dilemma of cooperation,we put forward relevant countermeasures and suggestions from the four dimensions of government,enterprises,think tanks and people.展开更多
We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on t...We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels.The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path.It can reverse the perturbed entanglement intensity evolution to its original state.Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly.In the process we can get the classical information described by information gain from the quantum system through weak measurement operation.On the other hand,in order to realize complete reversibility,the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process.展开更多
This study was designed to measure the performance of county health systems in central and western China utilizing routine healthcare data.Drawing on a literature review and expert consultation,the study established a...This study was designed to measure the performance of county health systems in central and western China utilizing routine healthcare data.Drawing on a literature review and expert consultation,the study established a theoretical framework and an indicator system for performance review.Questionnaires were designed and disseminated to collect empirical data on health system performance in four counties of two central and western provinces.Quantitative data were subjected to descriptive statistical analysis through SPSS12.0.Three dimensions were introduced in the performance review framework—health outcomes,financial risk protection and consumer and provider satisfaction.Health outcomes were assessed from four secondary indicators:infant mortality rate;maternal mortality rate;under-5 child mortality rate;and the incidence of Class A and Class B notifiable diseases.Financial risk was assessed using two secondary indicators:the proportion of the cost of inpatient care that was reimbursed under the New Cooperative Medical System(NCMS) insurance scheme,and the rate of NCMS funds utilization.The assessment of satisfaction was made using two secondary indicators:the overall satisfaction of local residents with healthcare services,and the satisfaction of health practitioners at the township and village level.The study indicated better health system performance in the two counties in Chongqing than those in Shanxi.It was concluded that outcome framework scores can fairly reveal performance differences among county health systems in central and western China,and can provide practical evidence for optimizing the operation and inputs of county health systems.Caution needs to be exercised in generalizing such performance outcomes as many factors such as spending and organization that contribute to county health system performance were not included in the study.展开更多
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R...The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters.展开更多
We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states....We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states. We conclude that the condition of higher order squeezing for quadrature components of the field is order independent and the fluctuations of measured phase operators are temperature independent.展开更多
The variation of air temperature measurement errors using two different radiation shields (DTR502B Vaisala,Finland,and HYTFZ01,Huayun Tongda Satcom,China) was studied.Datasets were collected in the field at the Daxi...The variation of air temperature measurement errors using two different radiation shields (DTR502B Vaisala,Finland,and HYTFZ01,Huayun Tongda Satcom,China) was studied.Datasets were collected in the field at the Daxing weather station in Beijing from June 2011 to May 2012.Most air temperature values obtained with these two commonly used radiation shields were lower than the reference records obtained with the new Fiber Reinforced Polymers (FRP) Stevenson screen.In most cases,the air temperature errors when using the two devices were smaller on overcast and rainy days than on sunny days; and smaller when using the imported rather than the Chinese shield.The measured errors changed sharply at sunrise and sunset,and reached maxima at noon.Their diurnal variation characteristics were,naturally,related to changes in solar radiation.The relationships between the record errors,global radiation,and wind speed were nonlinear.An improved correction method was proposed based on the approach described by Nakamura and Mahrt (2005) (NM05),in which the impact of the solar zenith angle (SZA) on the temperature error is considered and extreme errors due to changes in SZA can be corrected effectively.Measurement errors were reduced significantly after correction by either method for both shields.The error reduction rate using the improved correction method for the Chinese and imported shields were 3.3% and 40.4% higher than those using the NM05 method,respectively.展开更多
By using the theory of measured phase operator proposed by Barnett and Pegg, dynamic properties of the phase of a field are studied. The time evolution and squeezing of measured phase operators of a coherent field int...By using the theory of measured phase operator proposed by Barnett and Pegg, dynamic properties of the phase of a field are studied. The time evolution and squeezing of measured phase operators of a coherent field interacting with a two-level atom in the cavity with or without the Kerr medium are investigated. The influences of virtual cavity field on squeezing of measured phase operator are studied. Our numerical results show that the squeezing effects are clearly influenced by Kerr medium parameters, the field intensity, and the detuning. Moreover, the influence of the virtual-photon field makes more quantum noise in the evolution of measured phase operators. Key words Jaynes-Cummings model (JCM) - Kerr medium - measured phase operator - squeezing - virtual photon PACS 2001 4250Dv展开更多
Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for ev...Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for evaluating the O_(3)production rate.Furthermore,O_(x)has proved to be a more representative indicator and can serve as a reflection of pollution prevention efficacy.A portable instrument for measuring atmospheric O_(x)and NO_(2)based on cavity ring-down spectroscopy(O_(x)/NO_(2)-CRDS)was developed in this work.The NO_(2)concentration is accurately mea-sured according to its absorption characteristic at 407.86 nm.Ambient O_(3)is converted into NO_(2)by chemical titration of high concentrations of nitrogen oxide(NO),and the O_(3)conversion efficiencies obtained are nearly 99%.The detection limit of the O_(x)/NO_(2)-CRDS system for O_(x)is 0.024 ppbv(0.1 s),and the overall uncertainty of the instrument is±6%.Moreover,the Kalman filtering technique was applied to improve the measurement accuracy of O_(x)/NO_(2)-CRDS.The system was applied in a comprehensive field observation campaign at Hefei Sci-ence Island from 26 to 30 September 2022,and the time concentration series and change characteristics of O_(x)and NO_(2)were obtained for five days.The measured O_(x)concentrations were compared with those of two com-mercial instruments,and the consistency was good(R^(2)=0.98),indicating that this system can be deployed to accurately and rapidly obtain the concentrations of atmospheric O_(x)and NO_(2).It will be a useful tool for assessing the atmospheric oxidation capacity and controlling O_(3)pollution.展开更多
Measured surface localization (MSL) is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search betw...Measured surface localization (MSL) is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search between two surfaces, the performance improvement of localization algorithms and the uncertainty analysis of localization. However, low efficiency, limitation of localization algo- rithms and mismatch of multiple similarities of feature points with no prior are the common disadvantages for MSL. In order to match feature points quickly and fulfill MSL efficiently, this paper presents a new localization approach for measured surfaces by extracting the generic umbilics and estimating their single complex variables, describing the match methods of ambiguous relation at umbilics, presenting the initial localization process of one pair matched points, refining MSL on the basis of obtained closet points for some measured points by the improvement directed projection method. In addition, the proposed algorithm is simulated in two different types of surfaces,two different localization types and multiple similar sur- faces, also tested with the part of B-spline surface machined and bottle mould with no knowledge, finally the initial and accurate rigid body transformation matrix, localization errors between two surfaces and execution time are got. The experimental results show that the pro- posed method is feasible, more accurate in localization and high in efficiency. The proposed research can not only improve the accuracy and performance of form error assessment, but also provide an effective guideline for the integration of different types of measured surfaces.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 12302238)the National Key Research and Development Program of China (Grant Nos. 2021YFB3400701, 2022YFB3402904)。
文摘The dynamic load distribution within in-service axlebox bearings of high-speed trains is crucial for the fatigue reliability assessment and forward design of axlebox bearings. This paper presents an in situ measurement of the dynamic load distribution in the four rows of two axlebox bearings on a bogie wheelset of a high-speed train under polygonal wheel–rail excitation. The measurement employed an improved strain-based method to measure the dynamic radial load distribution of roller bearings. The four rows of two axlebox bearings on a wheelset exhibited different ranges of loaded zones and different means of distributed loads. Besides, the mean value and standard deviation of measured roller–raceway contact loads showed non-monotonic variations with the frequency of wheel–rail excitation. The fatigue life of the four bearing rows under polygonal wheel–rail excitation was quantitatively predicted by compiling the measured roller–raceway contact load spectra of the most loaded position and considering the load spectra as input.
基金Project(2017G006-N)supported by the Project of Science and Technology Research and Development Program of China Railway Corporation。
文摘Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges.
基金supported by the Deanship of Graduate Studies and Scientific Research at Qassim University(QU-APC-2024-9/1).
文摘Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison.
基金financially supported by the National Natural Science Foundation of China(No.52204084)the Open Research Fund of the State Key Laboratory of Coal Resources and safe Mining,CUMT,China(No.SKLCRSM 23KF004)+3 种基金the Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities),China(No.FRF-IDRY-GD22-002)the Fundamental Research Funds for the Central Universities and the Youth Teacher International Exchange and Growth Program,China(No.QNXM20220009)the National Key R&D Program of China(Nos.2022YFC2905600 and 2022 YFC3004601)the Science,Technology&Innovation Project of Xiongan New Area,China(No.2023XAGG0061)。
文摘Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.
文摘The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a patient's health status directly from their perspective,encompassing various domains such as symptom severity,functional status,and overall quality of life.By integrating PROMs into routine clinical practice and research,healthcare providers can achieve a more nuanced understanding of patient experiences and tailor treatments accordingly.The deployment of PROMs supports dynamic patient-provider interactions,fostering better patient engagement and adherence to tre-atment plans.Moreover,PROMs are pivotal in clinical settings for monitoring disease progression and treatment efficacy,particularly in chronic and mental health conditions.However,challenges in implementing PROMs include data collection and management,integration into existing health systems,and acceptance by patients and providers.Overcoming these barriers necessitates technological advancements,policy development,and continuous education to enhance the acceptability and effectiveness of PROMs.The paper concludes with recommendations for future research and policy-making aimed at optimizing the use and impact of PROMs across healthcare settings.
文摘In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice.
文摘Based on two dimensions of supply and demand,we use six indicators to establish a rural inclusive financial development index and evaluate the development of China's rural inclusive finance. We use spatial panel data model to examine the relationship between financial inclusion and rural poverty. Results show that:( i) both the rural inclusive finance and rural residents' per capita consumption present spatial clustering feature and show significant spatial correlation;( ii) the development of rural inclusive finance has significant spatial effect on poverty alleviation along time and space dimensions. In this study,the paper puts forward policy recommendations on strengthening the rural financial resources flow and constructing diversified rural inclusive financial system.
基金National Natural Science Foundation of China(No. 50976108)
文摘The tooth surface shape of hypoid gear is very complicated, and tooth surface accuracy of hypoid gear can be measured by using the latticed measurement and scanning measurement. Advantages and disadvantages of the two measurement patterns are compared and application of their measurement data on hypoid gear's quality management is analyzed. How to use these measurement data to simulate the dynamical performance of hypoid gear is researched, and the intelligent predicton of the dynamical performance indexes of contact spot, root stress, vibration exciting forces and load distribution and hertz contact stress on the tooth surface are carried out. This research work has an important guiding sense to design and ma- chine hypoid gear with low vibration and noise.
基金financially supported by the National Science Foundation of China (grant no. 31400542 31460196)+1 种基金Guangxi Natural Science Foundation (grant 2016GXNSFBA380233)Guangxi special fund project for innovation-driven development (AA 17204087-8)
文摘Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion.
基金Sponsored by the National Natural Science Foundation of China (10772032)
文摘An infrared colorimetric radiation thermometrical system was established based on the theory of optical radiation. The dynamic temperature history of fuel air explosive (FAE) was measured to obtain the temperature responses of primary initiation FAE and secondary initiation FAE in real time. And the characteristics of their temperature history curves were compared and analyzed. The results show that the primary initiation FAE has higher explosion temperature and longer duration compared to the secondary initiation FAE.
基金Foundation item:National Social Science Fund of China Key Project“Research on Pathway Design and Policy Coordination for Integrated Precision Poverty Alleviation and Rural Village Vitalization in Western China”(18ASH006)National Social Science Fund of China Key Project“Major Investigation on Severe Poverty in Ethnic Minority Areas and Research on Poverty Trap Transcendence Strategy”(18ZDA121)Central Higher Education Institution Fund Project“Evaluation on Current Status of Anti-poverty Capacity Cooperation between China and Africa and Research on Pathway Optimization”(SWU1809341).
文摘Poverty eradication is an important goal of African social development.China has always attached great importance to exchanges and cooperation with African countries in the field of poverty reduction and with the deepening of the practice and understanding of China-Africa anti-poverty cooperation,industrial-capacity cooperation has become a new theme of poverty reduction and development in China-Africa cooperation at the 2016 Forum on China Africa Cooperation(FOCAC)—Africa-China Poverty Reduction and Development Conference.Through combing and analysis of relevant literature and data,we found that China-Africa industrial-capacity cooperation,which is based on infrastructure construction,industrial park construction and trade exchanges,has played an important role in poverty reduction and development in African countries by facilitating industrialization and agricultural modernization,enhancing endogenous motivation for poverty alleviation,and improving the sustainable livelihood of poor people.At present,in the practice of anti-poverty industrial-capacity cooperation between China and Africa,there are still difficulties such as weak anti-poverty foundation and cooperation paths yet to be optimized.Meanwhile,it is also faced with a series of risks and challenges such as intensified international competition.In order to improve the cooperation between China and Africa,promote anti-poverty benefits,optimize the implementation paths,and better solve the dilemma of cooperation,we put forward relevant countermeasures and suggestions from the four dimensions of government,enterprises,think tanks and people.
基金Project supported by the National Natural Science Foundation of China(Grant No.11504135)University Science and Technology Plan Project of Shandong Province,China(Grant Nos.J16LJ53).
文摘We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels.The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path.It can reverse the perturbed entanglement intensity evolution to its original state.Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly.In the process we can get the classical information described by information gain from the quantum system through weak measurement operation.On the other hand,in order to realize complete reversibility,the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process.
文摘This study was designed to measure the performance of county health systems in central and western China utilizing routine healthcare data.Drawing on a literature review and expert consultation,the study established a theoretical framework and an indicator system for performance review.Questionnaires were designed and disseminated to collect empirical data on health system performance in four counties of two central and western provinces.Quantitative data were subjected to descriptive statistical analysis through SPSS12.0.Three dimensions were introduced in the performance review framework—health outcomes,financial risk protection and consumer and provider satisfaction.Health outcomes were assessed from four secondary indicators:infant mortality rate;maternal mortality rate;under-5 child mortality rate;and the incidence of Class A and Class B notifiable diseases.Financial risk was assessed using two secondary indicators:the proportion of the cost of inpatient care that was reimbursed under the New Cooperative Medical System(NCMS) insurance scheme,and the rate of NCMS funds utilization.The assessment of satisfaction was made using two secondary indicators:the overall satisfaction of local residents with healthcare services,and the satisfaction of health practitioners at the township and village level.The study indicated better health system performance in the two counties in Chongqing than those in Shanxi.It was concluded that outcome framework scores can fairly reveal performance differences among county health systems in central and western China,and can provide practical evidence for optimizing the operation and inputs of county health systems.Caution needs to be exercised in generalizing such performance outcomes as many factors such as spending and organization that contribute to county health system performance were not included in the study.
基金supported by the National Key Research and Development Program of China(No.2023YFC2907600)the National Natural Science Foundation of China(Nos.42077267,42277174 and 52074164)+2 种基金the Natural Science Foundation of Shandong Province,China(No.ZR2020JQ23)the Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology(No.KFJJ21-02Z)the Fundamental Research Funds for the Central Universities,China(No.2022JCCXSB03).
文摘The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters.
文摘We study the higher order fluctuations and squeezing of quadrature operators in the squeezed thermal states. In terms of measured phase operators, we discuss the fluctuations and squeezing of phases in these states. We conclude that the condition of higher order squeezing for quadrature components of the field is order independent and the fluctuations of measured phase operators are temperature independent.
基金financially supported by the Meteorological Key Technology Integration and Application Project funded by the China Meteorological Administration (Grant No.CAMGJ2012M01)the Special Fund of Beijing Meteorological Bureau (Grant No.2011BMBKYZX04)the Nation Natural Science Foundation of China (Grant No.41275114)
文摘The variation of air temperature measurement errors using two different radiation shields (DTR502B Vaisala,Finland,and HYTFZ01,Huayun Tongda Satcom,China) was studied.Datasets were collected in the field at the Daxing weather station in Beijing from June 2011 to May 2012.Most air temperature values obtained with these two commonly used radiation shields were lower than the reference records obtained with the new Fiber Reinforced Polymers (FRP) Stevenson screen.In most cases,the air temperature errors when using the two devices were smaller on overcast and rainy days than on sunny days; and smaller when using the imported rather than the Chinese shield.The measured errors changed sharply at sunrise and sunset,and reached maxima at noon.Their diurnal variation characteristics were,naturally,related to changes in solar radiation.The relationships between the record errors,global radiation,and wind speed were nonlinear.An improved correction method was proposed based on the approach described by Nakamura and Mahrt (2005) (NM05),in which the impact of the solar zenith angle (SZA) on the temperature error is considered and extreme errors due to changes in SZA can be corrected effectively.Measurement errors were reduced significantly after correction by either method for both shields.The error reduction rate using the improved correction method for the Chinese and imported shields were 3.3% and 40.4% higher than those using the NM05 method,respectively.
文摘By using the theory of measured phase operator proposed by Barnett and Pegg, dynamic properties of the phase of a field are studied. The time evolution and squeezing of measured phase operators of a coherent field interacting with a two-level atom in the cavity with or without the Kerr medium are investigated. The influences of virtual cavity field on squeezing of measured phase operator are studied. Our numerical results show that the squeezing effects are clearly influenced by Kerr medium parameters, the field intensity, and the detuning. Moreover, the influence of the virtual-photon field makes more quantum noise in the evolution of measured phase operators. Key words Jaynes-Cummings model (JCM) - Kerr medium - measured phase operator - squeezing - virtual photon PACS 2001 4250Dv
基金supported by the National Natural Science Foundation of China[grant number 62275250]the Natural Science Foundation of Anhui Province[grant number 2008085J20]+1 种基金the National Key R&D Program of China[grant number 2022YFC3700301]the Anhui Provincial Key R&D Program[grant number 2022l07020022]。
文摘Atmospheric O_(x)(nitrogen dioxide(NO_(2))+ozone(O_(3)))can better reflect the local and regional change character-istics of oxidants compared to O_(3)alone,so obtaining O_(x)accurately and rapidly is the basis for evaluating the O_(3)production rate.Furthermore,O_(x)has proved to be a more representative indicator and can serve as a reflection of pollution prevention efficacy.A portable instrument for measuring atmospheric O_(x)and NO_(2)based on cavity ring-down spectroscopy(O_(x)/NO_(2)-CRDS)was developed in this work.The NO_(2)concentration is accurately mea-sured according to its absorption characteristic at 407.86 nm.Ambient O_(3)is converted into NO_(2)by chemical titration of high concentrations of nitrogen oxide(NO),and the O_(3)conversion efficiencies obtained are nearly 99%.The detection limit of the O_(x)/NO_(2)-CRDS system for O_(x)is 0.024 ppbv(0.1 s),and the overall uncertainty of the instrument is±6%.Moreover,the Kalman filtering technique was applied to improve the measurement accuracy of O_(x)/NO_(2)-CRDS.The system was applied in a comprehensive field observation campaign at Hefei Sci-ence Island from 26 to 30 September 2022,and the time concentration series and change characteristics of O_(x)and NO_(2)were obtained for five days.The measured O_(x)concentrations were compared with those of two com-mercial instruments,and the consistency was good(R^(2)=0.98),indicating that this system can be deployed to accurately and rapidly obtain the concentrations of atmospheric O_(x)and NO_(2).It will be a useful tool for assessing the atmospheric oxidation capacity and controlling O_(3)pollution.
基金Supported by Science and Technology Supporting Projects of China(Grant No.2015BAF27B01)Sichuan Provincial Science and Technology Supporting Program of China(Grant Nos.2014GZ0119,2017GZ0350)Open Research Fund of Key Laboratory of Manufacturing and Automation,Xihua University(Grant No.S2jj2013-042)
文摘Measured surface localization (MSL) is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search between two surfaces, the performance improvement of localization algorithms and the uncertainty analysis of localization. However, low efficiency, limitation of localization algo- rithms and mismatch of multiple similarities of feature points with no prior are the common disadvantages for MSL. In order to match feature points quickly and fulfill MSL efficiently, this paper presents a new localization approach for measured surfaces by extracting the generic umbilics and estimating their single complex variables, describing the match methods of ambiguous relation at umbilics, presenting the initial localization process of one pair matched points, refining MSL on the basis of obtained closet points for some measured points by the improvement directed projection method. In addition, the proposed algorithm is simulated in two different types of surfaces,two different localization types and multiple similar sur- faces, also tested with the part of B-spline surface machined and bottle mould with no knowledge, finally the initial and accurate rigid body transformation matrix, localization errors between two surfaces and execution time are got. The experimental results show that the pro- posed method is feasible, more accurate in localization and high in efficiency. The proposed research can not only improve the accuracy and performance of form error assessment, but also provide an effective guideline for the integration of different types of measured surfaces.