In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries a...In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries across the world is gathered with their reported settlements. The results showed that the GP model is able to estimate the dam settlement properly based on four properties, void ratio of dam’s body (e), height (H), vertical deformation modulus (Ev) and shape factor (Sc) of the dam. For verification of the model applicability, obtained results compared with other research methods such as Clements’s formula and the finite element model. The comparison showed that in all cases the GP model led to be more accurate than those of performed in literature. Also a proper compatibility between the GP model and the finite element model was perceived.展开更多
Black fungus derived carbonaceous aerogel (BFA) was prepared via a convenient and energy efficient ultrasonic disposal process. The adsorption experiments of atmospheric pollutants demonstrated the superior adsorbabil...Black fungus derived carbonaceous aerogel (BFA) was prepared via a convenient and energy efficient ultrasonic disposal process. The adsorption experiments of atmospheric pollutants demonstrated the superior adsorbability of black fungus aerogel on PM2.5, PM10 and formaldehyde. More importantly, black fungus aerogel (BFA) exhibited intriguing double-faced properties. We explored properties of each side of the black fungus from three aspects: water contact angle measurements, liquid selective absorption capacity and air pollutant adsorption abilities. The subsequent modification of ZnO nanosheets endowed the prepared black fungus aerogel with several valuable properties, including broad-spectrum antibacterial capability and high-efficient adsorption ability. These valuable characters implied the BFA to be a promising bacteriostat and cleaner for air and water pollution treatment.展开更多
Double - faced iso - object embroidery is carried out byusing the uneven intercalated stitch crafts of the parallel- lines stitch as a main body, being accompanied by oth-er stitch crafts and miscellaneous stitches, d...Double - faced iso - object embroidery is carried out byusing the uneven intercalated stitch crafts of the parallel- lines stitch as a main body, being accompanied by oth-er stitch crafts and miscellaneous stitches, done on thesame textile material. This paper deals with the flower -bird double - faced embroidery fan of the Qing Dynasty,from pattern design, stitching formation and techniqueof color arrangement, describes the possible way of mak-ing double - faced embroidery with iso - object effectboth in the front and in the back.展开更多
Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presen...Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presents the following characteristics:1.The understanding of life was deepened to the molecule level.展开更多
State-owned enterprises’(SOE) greater independence from government offices as well as property rights reform have optimized SOEs’ shareholding structure. But the reform has to clear several hurdles before it can be ...State-owned enterprises’(SOE) greater independence from government offices as well as property rights reform have optimized SOEs’ shareholding structure. But the reform has to clear several hurdles before it can be fully realized. In 1998, the central government dismantled ministries that had been the direct administrators of large SOEs. Most functions of those ministries were transferred to industry associations. Only a few considered indispensable were taken over by other government offices. The move has pushed forward the SOE reform to some extent. On the other hand, being State-owned, those enterprises have to find new links with the government.展开更多
Under over 50 years' development, Chinese rare earth magnetic industry developed into the global AINiCo, ferrite permanent magnets and NdFeB magnets manufacturing center, and average consumption of magnets per per...Under over 50 years' development, Chinese rare earth magnetic industry developed into the global AINiCo, ferrite permanent magnets and NdFeB magnets manufacturing center, and average consumption of magnets per person in China increased to 1.026 tons in 2003 from 0.217 ton in 1990. Although China has been the large producing country of rare earth permanent magnetic materials, to be the strongest one, there are many problems to solve. Main Problems Faced By Chinese Permanent Magnet展开更多
Owing to the stochastic behavior of earthquakes and complex crustal structure,wave type and incident direction are uncertain when seismic waves arrive at a structure.In addition,because of the different types of the s...Owing to the stochastic behavior of earthquakes and complex crustal structure,wave type and incident direction are uncertain when seismic waves arrive at a structure.In addition,because of the different types of the structures and terrains,the traveling wave effects have different influences on the dynamic response of the structures.For the tall concrete-faced rockfill dam(CFRD),it is not only built in the complex terrain such as river valley,but also its height has reached 300 m level,which puts forward higher requirements for the seismic safety of the anti-seepage system mainly comprising concrete face slabs,especially the accurate location of the weak area in seism.Considering the limitations of the traditional uniform vibration analysis method,we implemented an efficient dynamic interaction analysis between a tall CFRD and its foundation using a non-uniform wave input method with a viscous-spring artificial boundary and equivalent nodal loads.This method was then applied to investigate the dynamic stress distribution on the concrete face slabs for different seismic wave types and incident directions.The results indicate that dam-foundation interactions behave differently at different wave incident angles,and that the traveling wave effect becomes more evident in valley topography.Seismic wave type and incident direction dramatically influenced stress in the face slab,and the extreme stress values and distribution law will vary under oblique wave incidence.The influence of the incident direction on slab stress was particularly apparent when SH-waves arrived from the left bank.Specifically,the extreme stress values in the face slab increased with an increasing incident angle.Interestingly,the locations of the extreme stress values changed mainly along the axis of the dam,and did not exhibit large changes in height.The seismic safety of CFRDs is therefore lower at higher incident angles from an anti-seepage perspective.Therefore,it is necessary to consider both the seismic wave type and incident direction during seismic capacity evaluations of tall CFRDs.展开更多
Demand for simple and effective gas sensing sensors is growing rapidly due to the growing threat of triethylamine(TEA).Semiconductor tin oxide(SnO_(2))is one of the most widely used sensing materials for metal oxide g...Demand for simple and effective gas sensing sensors is growing rapidly due to the growing threat of triethylamine(TEA).Semiconductor tin oxide(SnO_(2))is one of the most widely used sensing materials for metal oxide gas sensors.In recent years,a lot of binary ternary compound researches have been carried out.In this paper,five different SnO_(2) samples were synthesized by simple synthesis method to understand the internal relationship and obtain different gas sensing characteristics.Based on the low temperature nitrogen adsorption tests and the atomic arrangement model,it can be inferred that different exposed surfaces play a key role in TEA sensing properties.In addition,the TEA sensing activity relationship of SnO_(2) exposed crystal faces is proposed as listed:(200)>(101)>(110).展开更多
In recent years, China's economic development has driven the development of the construction industry. The project cost consulting business has developed rapidly, creating a good environment for local economic dev...In recent years, China's economic development has driven the development of the construction industry. The project cost consulting business has developed rapidly, creating a good environment for local economic development. Project cost consulting management can effectively improve the scientificity of project decision-making and maximize economic and social benefits. In the process of this work, we should pay attention to risk prevention and control measures to give full play to its value. Next, the article discusses the risks and preventive countermeasures faced by the project cost consulting management.展开更多
Considering the complex nonlinear relationship between the material parameters of a concrete faced rock-fill dam(CFRD) and its displacements, the harmony search(HS) algorithm is used to optimize the back propagation n...Considering the complex nonlinear relationship between the material parameters of a concrete faced rock-fill dam(CFRD) and its displacements, the harmony search(HS) algorithm is used to optimize the back propagation neural network(BPNN), and the HS-BPNN algorithm is formed and applied for the inversion analysis of the parameters of rock-fill materials. The sensitivity of the parameters in the Duncan and Chang's E-B model is analyzed using the orthogonal test design. The case study shows that the parameters φ0, K, Rf, and Kb are sensitive to the deformation of the rock-fill dam and the inversion analysis for these parameters is performed by the HS-BPNN algorithm. Compared with the traditional BPNN, the HS-BPNN algorithm exhibits the advantages of high convergence precision, fast convergence rate, and strong stability.展开更多
This paper summarizes the main technical points related to 100 m-height-scale concrete faced rock-fill dams and analyzes the main problems and their causes occurring during construction of 200 m-height-scale concrete ...This paper summarizes the main technical points related to 100 m-height-scale concrete faced rock-fill dams and analyzes the main problems and their causes occurring during construction of 200 m-height-scale concrete faced rock-fill dams. This paper has raised the key technical problems which need to study for construction of 300 m-height-scale concrete faced rock-fill dams based on the main experiences on the extra-high concrete faced rock-fill dams built after the year of 2000.展开更多
ESP teachers teaching English for mixed subject -specialist groups meet problems such as selecting teach-ing materials,dealing with the subject matter,and teaching methods.The experience in the ATTSR(Advanced Teacher ...ESP teachers teaching English for mixed subject -specialist groups meet problems such as selecting teach-ing materials,dealing with the subject matter,and teaching methods.The experience in the ATTSR(Advanced Teacher Training in Specialist Reading)project may be a reference point for colleagues whomeet with the same problems.In this paper the author will suggest methods to solve these problems intraining this group:using different subject展开更多
Subject Code:A04With the financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics,Tsinghua University recently publishe...Subject Code:A04With the financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics,Tsinghua University recently published their seminal work in Nature(2017,546:124—128).The work,titled“Electric-field control展开更多
With financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics in Tsinghua University published their seminal work recen...With financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics in Tsinghua University published their seminal work recently in the prestigious journal Nature(2017,546:124-128).The work。展开更多
Jade was considered an elegant stone in ancient China. People began wearing jade ornaments as decorations as early as the Neolithic Period. This grey jade ornament, two centimeters long, was made during the third cult...Jade was considered an elegant stone in ancient China. People began wearing jade ornaments as decorations as early as the Neolithic Period. This grey jade ornament, two centimeters long, was made during the third cultural period展开更多
Estimating the cracking capacity of the face slab and recommending effective crack-control measures are important for the anti-seismic safety of concrete-faced rockfill dams(CFRDs). In this paper, two-dimensional anal...Estimating the cracking capacity of the face slab and recommending effective crack-control measures are important for the anti-seismic safety of concrete-faced rockfill dams(CFRDs). In this paper, two-dimensional analyses of CFRDs are performed to simulate the seismic cracking behavior of conventional reinforced concrete(RC) face slab and a type of composite face slab. The composite face slab is composed of a ductile fiber-reinforced cement-based composite(DFRCC) layer and an RC substrate. For this purpose, a co-axial rotating smeared crack model for concrete and DFRCC is coupled with the generalized plasticity model for the rockfill material, and then implemented in a finite element program. The results show that during strong earthquakes,an RC slab is more likely to develop a penetrating macro-crack in its thickness dimension. In contrast, the crack-controlling composite slab demonstrates excellent resistance to seismic cracking, and no penetrating macro-cracks are observed. Major harmful cracks that form in the concrete substrate are stopped by the DFRCC layer in composite slabs.展开更多
1.Limited land resources restrict de-velopmentThe natural rubber sector is a typicalresource-constrained sector.The landarea suitable for rubber planting isvery limited in China-only 970 thou-sand hectares-and 70% of ...1.Limited land resources restrict de-velopmentThe natural rubber sector is a typicalresource-constrained sector.The landarea suitable for rubber planting isvery limited in China-only 970 thou-sand hectares-and 70% of it is alreadyin use.The remaining area is mostlyalready in productive use,plantedwith other tropical crops.It is there-fore not very feasible to increase theoutput of natural rubber by expand-ing the planting area.展开更多
文摘In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries across the world is gathered with their reported settlements. The results showed that the GP model is able to estimate the dam settlement properly based on four properties, void ratio of dam’s body (e), height (H), vertical deformation modulus (Ev) and shape factor (Sc) of the dam. For verification of the model applicability, obtained results compared with other research methods such as Clements’s formula and the finite element model. The comparison showed that in all cases the GP model led to be more accurate than those of performed in literature. Also a proper compatibility between the GP model and the finite element model was perceived.
基金the National Natural Science Foundation of China(Nos. 21461015, 31860263 to Xiaolei Wang No. 91639106 to Hongbo Xin)+1 种基金Science Foundation of Jiangxi Provincial Department of Education(Nos. KJLD14010, 20153BCB23035, 20161ACB21002, 20165BCB19002 to Xiaolei Wang)Nanchang University Seed Grant for Biomedicine
文摘Black fungus derived carbonaceous aerogel (BFA) was prepared via a convenient and energy efficient ultrasonic disposal process. The adsorption experiments of atmospheric pollutants demonstrated the superior adsorbability of black fungus aerogel on PM2.5, PM10 and formaldehyde. More importantly, black fungus aerogel (BFA) exhibited intriguing double-faced properties. We explored properties of each side of the black fungus from three aspects: water contact angle measurements, liquid selective absorption capacity and air pollutant adsorption abilities. The subsequent modification of ZnO nanosheets endowed the prepared black fungus aerogel with several valuable properties, including broad-spectrum antibacterial capability and high-efficient adsorption ability. These valuable characters implied the BFA to be a promising bacteriostat and cleaner for air and water pollution treatment.
文摘Double - faced iso - object embroidery is carried out byusing the uneven intercalated stitch crafts of the parallel- lines stitch as a main body, being accompanied by oth-er stitch crafts and miscellaneous stitches, done on thesame textile material. This paper deals with the flower -bird double - faced embroidery fan of the Qing Dynasty,from pattern design, stitching formation and techniqueof color arrangement, describes the possible way of mak-ing double - faced embroidery with iso - object effectboth in the front and in the back.
文摘Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presents the following characteristics:1.The understanding of life was deepened to the molecule level.
文摘State-owned enterprises’(SOE) greater independence from government offices as well as property rights reform have optimized SOEs’ shareholding structure. But the reform has to clear several hurdles before it can be fully realized. In 1998, the central government dismantled ministries that had been the direct administrators of large SOEs. Most functions of those ministries were transferred to industry associations. Only a few considered indispensable were taken over by other government offices. The move has pushed forward the SOE reform to some extent. On the other hand, being State-owned, those enterprises have to find new links with the government.
文摘Under over 50 years' development, Chinese rare earth magnetic industry developed into the global AINiCo, ferrite permanent magnets and NdFeB magnets manufacturing center, and average consumption of magnets per person in China increased to 1.026 tons in 2003 from 0.217 ton in 1990. Although China has been the large producing country of rare earth permanent magnetic materials, to be the strongest one, there are many problems to solve. Main Problems Faced By Chinese Permanent Magnet
基金supported by the National Natural Science Foundation of China(Nos.52192674,U1965206,U2240211)the Fundamental Research Funds for the Central Universities(No.DUT21TD106)。
文摘Owing to the stochastic behavior of earthquakes and complex crustal structure,wave type and incident direction are uncertain when seismic waves arrive at a structure.In addition,because of the different types of the structures and terrains,the traveling wave effects have different influences on the dynamic response of the structures.For the tall concrete-faced rockfill dam(CFRD),it is not only built in the complex terrain such as river valley,but also its height has reached 300 m level,which puts forward higher requirements for the seismic safety of the anti-seepage system mainly comprising concrete face slabs,especially the accurate location of the weak area in seism.Considering the limitations of the traditional uniform vibration analysis method,we implemented an efficient dynamic interaction analysis between a tall CFRD and its foundation using a non-uniform wave input method with a viscous-spring artificial boundary and equivalent nodal loads.This method was then applied to investigate the dynamic stress distribution on the concrete face slabs for different seismic wave types and incident directions.The results indicate that dam-foundation interactions behave differently at different wave incident angles,and that the traveling wave effect becomes more evident in valley topography.Seismic wave type and incident direction dramatically influenced stress in the face slab,and the extreme stress values and distribution law will vary under oblique wave incidence.The influence of the incident direction on slab stress was particularly apparent when SH-waves arrived from the left bank.Specifically,the extreme stress values in the face slab increased with an increasing incident angle.Interestingly,the locations of the extreme stress values changed mainly along the axis of the dam,and did not exhibit large changes in height.The seismic safety of CFRDs is therefore lower at higher incident angles from an anti-seepage perspective.Therefore,it is necessary to consider both the seismic wave type and incident direction during seismic capacity evaluations of tall CFRDs.
基金financially supported by Shandong Provincial Key R&D Plan Program(No.2017GGX10135)Shandong Provincial Science Foundation(No.ZR2018LF013)。
文摘Demand for simple and effective gas sensing sensors is growing rapidly due to the growing threat of triethylamine(TEA).Semiconductor tin oxide(SnO_(2))is one of the most widely used sensing materials for metal oxide gas sensors.In recent years,a lot of binary ternary compound researches have been carried out.In this paper,five different SnO_(2) samples were synthesized by simple synthesis method to understand the internal relationship and obtain different gas sensing characteristics.Based on the low temperature nitrogen adsorption tests and the atomic arrangement model,it can be inferred that different exposed surfaces play a key role in TEA sensing properties.In addition,the TEA sensing activity relationship of SnO_(2) exposed crystal faces is proposed as listed:(200)>(101)>(110).
文摘In recent years, China's economic development has driven the development of the construction industry. The project cost consulting business has developed rapidly, creating a good environment for local economic development. Project cost consulting management can effectively improve the scientificity of project decision-making and maximize economic and social benefits. In the process of this work, we should pay attention to risk prevention and control measures to give full play to its value. Next, the article discusses the risks and preventive countermeasures faced by the project cost consulting management.
基金supported by the National Natural Science Foundation of China(Grant Nos.51579086,51479054,51379068&51139001)Jiangsu Natural Science Foundation(Grant No.BK20140039)the Priority Academic Program Development of Jiangsu Higher Education Institutions(Grant No.YS11001)
文摘Considering the complex nonlinear relationship between the material parameters of a concrete faced rock-fill dam(CFRD) and its displacements, the harmony search(HS) algorithm is used to optimize the back propagation neural network(BPNN), and the HS-BPNN algorithm is formed and applied for the inversion analysis of the parameters of rock-fill materials. The sensitivity of the parameters in the Duncan and Chang's E-B model is analyzed using the orthogonal test design. The case study shows that the parameters φ0, K, Rf, and Kb are sensitive to the deformation of the rock-fill dam and the inversion analysis for these parameters is performed by the HS-BPNN algorithm. Compared with the traditional BPNN, the HS-BPNN algorithm exhibits the advantages of high convergence precision, fast convergence rate, and strong stability.
文摘This paper summarizes the main technical points related to 100 m-height-scale concrete faced rock-fill dams and analyzes the main problems and their causes occurring during construction of 200 m-height-scale concrete faced rock-fill dams. This paper has raised the key technical problems which need to study for construction of 300 m-height-scale concrete faced rock-fill dams based on the main experiences on the extra-high concrete faced rock-fill dams built after the year of 2000.
文摘ESP teachers teaching English for mixed subject -specialist groups meet problems such as selecting teach-ing materials,dealing with the subject matter,and teaching methods.The experience in the ATTSR(Advanced Teacher Training in Specialist Reading)project may be a reference point for colleagues whomeet with the same problems.In this paper the author will suggest methods to solve these problems intraining this group:using different subject
文摘Subject Code:A04With the financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics,Tsinghua University recently published their seminal work in Nature(2017,546:124—128).The work,titled“Electric-field control
文摘With financial support from the National Natural Science Foundation of China,a research team led by Associate Professor Yu Pu(于浦)at the Department of Physics in Tsinghua University published their seminal work recently in the prestigious journal Nature(2017,546:124-128).The work。
文摘Jade was considered an elegant stone in ancient China. People began wearing jade ornaments as decorations as early as the Neolithic Period. This grey jade ornament, two centimeters long, was made during the third cultural period
基金supported by the National Natural Science Foundation of China(Grant Nos.51379028,51421064&51279025)
文摘Estimating the cracking capacity of the face slab and recommending effective crack-control measures are important for the anti-seismic safety of concrete-faced rockfill dams(CFRDs). In this paper, two-dimensional analyses of CFRDs are performed to simulate the seismic cracking behavior of conventional reinforced concrete(RC) face slab and a type of composite face slab. The composite face slab is composed of a ductile fiber-reinforced cement-based composite(DFRCC) layer and an RC substrate. For this purpose, a co-axial rotating smeared crack model for concrete and DFRCC is coupled with the generalized plasticity model for the rockfill material, and then implemented in a finite element program. The results show that during strong earthquakes,an RC slab is more likely to develop a penetrating macro-crack in its thickness dimension. In contrast, the crack-controlling composite slab demonstrates excellent resistance to seismic cracking, and no penetrating macro-cracks are observed. Major harmful cracks that form in the concrete substrate are stopped by the DFRCC layer in composite slabs.
文摘1.Limited land resources restrict de-velopmentThe natural rubber sector is a typicalresource-constrained sector.The landarea suitable for rubber planting isvery limited in China-only 970 thou-sand hectares-and 70% of it is alreadyin use.The remaining area is mostlyalready in productive use,plantedwith other tropical crops.It is there-fore not very feasible to increase theoutput of natural rubber by expand-ing the planting area.