Through the Latour concept of philosophy of science of laboratory life,the life course of a(geo)ethnographer researcher is analyzed,in order to establish the emotional or more personal dimensions that do not usually a...Through the Latour concept of philosophy of science of laboratory life,the life course of a(geo)ethnographer researcher is analyzed,in order to establish the emotional or more personal dimensions that do not usually appear in research papers,but that have notable relevance in qualitative research.The text is structured in three large parts:A conceptual vision of the new experimental geography;the experimental geo-ethnography in old social,new social and place scenarios;and finally,the most personal and emotional dimension of the research.The first part establishes the geo-ethnographic experimental context and the assumptions in fieldwork,in addition to the geo-ethnographic reconciliation process.In the second part,the main qualitative research problems related to mobility,resistance and dynamics in place are established.Finally,in the third part the research perceptions,the personal experiences,and the emotional dimension of the research in remote rural areas are established.The laboratory life of a researcher,allows one to establish scalar conclusions and rigor in qualitative research.展开更多
In view of the importance of gas-liquid two-phase spiral flow and the few research reports at home and abroad,the gas-liquid two-phase spiral flow patterns have been researched in a horizontal pipe with different para...In view of the importance of gas-liquid two-phase spiral flow and the few research reports at home and abroad,the gas-liquid two-phase spiral flow patterns have been researched in a horizontal pipe with different parameters investigated by means of observation and a high-speed camera.Since the appearance of spiral flow makes the distribution of twophase flow more complicated,the flow patterns appearing in the experiments were divided into the Spiral Wavy Stratified Flow(SWS),the Spiral Bubble Flow(SB),the Spiral Slug Flow(SS),the Spiral Linear Flow(SL),the Spiral Axial Flow(SA),and the Spiral Dispersed Flow(SD) by the observations and with reference to the predecessors' research achievements.A flow pattern map has been drawn up.The influence of velocity,vane angle and vane area on flow pattern conversion boundary and pressure drop has been studied,with a solid foundation laid for the future research work.展开更多
The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendlin...The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendliness.The heat storage process of the Ca(OH)_(2)/CaO TCES system in a mixed heating reactor was evaluated in this study,by employing a combination of direct and indirect heating modes.The dehydration process was studied experimentally,and a numerical model was established and verified based on the experimental results.The dehydration behavior of 500 g of Ca(OH)_(2) powder was investigated in a fixed-bed reactor with mixed heating.The experimental and simulation results indicated that mixed heating causes combined centripetal and horizontal propulsion.Heat input is the main limiting factor in the heat storage process,because the radial advance of the reaction is hindered by the low thermal conductivity of the solid reactant particles.Heat transmission partitions were added to enhance the performance of the reactor.The performance of the modified reactor was compared with that of a conventional reactor.The radial heat transmission partitions in the modified reactor effectively enhance the energy storage rate and reduce the reaction time by 59.5%compared with the reactor without partitions.展开更多
The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, d...The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, distance of fin space, frost, and velocity of air flow etc. They mainly influence the thermal efficiency of an evaporator, and therefore its thermal efficiency has direct relationship with the whole efficiency of the quick freeze plant. Evaporators with different structural types have different heat transfer efficiency, in order to obtain high efficiency structure of evaporator, 8 evaporator models with different fin shape, tube diameter and tube arrangement are analyzed and compared. The calculation results show that the integral waved fins, equilateral-triangle arranged small diameter tubes and varying fin-spacing has the highest heat transfer coefficient. The experimental result also shows that the evaporator with this type of structure has better thermal efficiency. The experimental result is in good agreement with the calculation result, it can instruct engineering design for usual designer. A real quick-freeze equipment is designed and put into production. The result shows that, compared with traditional domestic quick-freeze equipments, this equipment decreases by 40% in size and by 20% in energy consumption.展开更多
The absence of effective therapies for castration-resistant prostate cancer(CRPC) establishes the need to develop novel therapeutic modality, such as targeted gene therapy, which is ideal for the treatment of CRPC. Bu...The absence of effective therapies for castration-resistant prostate cancer(CRPC) establishes the need to develop novel therapeutic modality, such as targeted gene therapy, which is ideal for the treatment of CRPC. But its application has been limited due to lack of favorable gene vector and the reduction of "bystander effect". Consequently, scientists all over the world focus their main experimental research on the following four aspects: targeted gene, vector, transfer means and comprehensive therapy. In this paper, we reviewed the latest advances of experimental research on targeted gene therapy for prostate cancer.展开更多
Polysocoharibe-peptide of Coriolus Versicolor (PSP) is a new anti-cancer immunomodulative drug. The present paper reports on the experimental research done with this drug. It was found that PSP had the ability to reco...Polysocoharibe-peptide of Coriolus Versicolor (PSP) is a new anti-cancer immunomodulative drug. The present paper reports on the experimental research done with this drug. It was found that PSP had the ability to recover hemolysin HC50, to increase the weight of the thymus, and increase the alexin of serum C3 and the IgG content of tumor bearing mice. FSP also significantly raised the pha-gocytic activity of macrophages in normal mice. PSP had a significant inhibitory effect on P38S and S180 cells. At the concentration of 1 mg/ml, PSP inhibited the proliferating activity of some human tumor call lines, such as SGC 7901, SPC, SLY and Mei. It had a direct toxic effect on SPC cells. PSP significantly inhibited the synthesis of nucleic acids of Ehrlich ascites carcinoma cells. In addition, PSP was antagonistic to the side effects of chemotherapy and radiotherapy.展开更多
?Fundamental experiments on lower hybrid current drive (LHCD) have been undertaken on HT-7 superconducting tokamak. The experiments on LHCD efficiency reveal its depen- deuce on plasma density and the toroidal magnet...?Fundamental experiments on lower hybrid current drive (LHCD) have been undertaken on HT-7 superconducting tokamak. The experiments on LHCD efficiency reveal its depen- deuce on plasma density and the toroidal magnetic field. Furthermore, the experiments on HT-7 successfully demonstrate the ability for LHCD to sustain long pulse tokamak discharges, such as discharges with full non-inductive current drive for several seconds. The experimental study to improve plasma confinements by LHCD suggests that the improvement should be due to the change o f current profile. It has also been demonstrated by the experiments that the lower hybrid wave may lead to an enhanced ionization of particles in the region where the wave is deposited.展开更多
The calculated and experimental research of sheet resistances of crystalline silicon solar cells by dry laser doping is investigated. The nonlinear numerical model on laser melting of crystalline silicon and liquid-ph...The calculated and experimental research of sheet resistances of crystalline silicon solar cells by dry laser doping is investigated. The nonlinear numerical model on laser melting of crystalline silicon and liquid-phase diffusion of phosphorus atoms by dry laser doping is analyzed by the finite difference method implemented in MATLAB. The melting period and melting depth of crystalline silicon as a function of laser energy density is achieved. The effective liquid-phase diffusion of phosphorus atoms in melting silicon by dry laser doping is confirmed by the rapid decrease of sheet resistances in experimental measurement. The plateau of sheet resistances is reached at around 15 Ω/. The calculated sheet resistances as a function of laser energy density is obtained and the calculated results are in good agreement with the corresponding experimental measurement. Due to the successful verification by comparison between experimental measurement and calculated results, the simulation results could be used to optimize the virtual laser doping parameters.展开更多
In order to study the propagation mechanism of continuous rotating detonation wave,the H2/air continuous rotating detonation engine ignited by tangentially installed H2/O2pre-detonation tube is studied experimentally ...In order to study the propagation mechanism of continuous rotating detonation wave,the H2/air continuous rotating detonation engine ignited by tangentially installed H2/O2pre-detonation tube is studied experimentally using a tilt slot injector structure.The experimental results show that the stable rotating detonation wave can be gained successfully with the equivalent ratio of 0.93.The propagation frequency and velocity of rotating detonation wave range from 5200 to 5500 Hz and from 1518.5 to 1606.1 m/s,respectively.Three propagation modes,such as rotation,reversal and bifurcation,of detonation wave are verified through the analysis of propagation mechanism of rotating detonation wave.展开更多
At present,rail transit is developing rapidly in the world,and this means new and changing requirements for the training of talents in railway engineering experiments.Given the current problems of limited laboratory/f...At present,rail transit is developing rapidly in the world,and this means new and changing requirements for the training of talents in railway engineering experiments.Given the current problems of limited laboratory/field instruments for railway engineering experimentsand the safety/administrative difficulties of going to the frontline of railway lines to teach railway engineering experiemnts in the field,the Department of Railway Engineering of Central South University tried to introduce virtual reality(VR)technology to teach students experiments in the field of railway engineering.Through the virtualized experimental methods,students can carry out railway engineering experiments such as;vehicle wheel pair off-axis experiments,track geometry and position detection,etc.by immersive means.It was observed that after performing virtual simulation experiments,students appeared conversant in subsequent field experiments.Thus,VR greatly improves the teaching efficiency of railway engineering experiments.展开更多
This paper introduces a new kind of armour block - hexagon multihole block on sloping breakwater. It has great characteristics such as good interlocking, strong resistance against waves and saving concrete. Through th...This paper introduces a new kind of armour block - hexagon multihole block on sloping breakwater. It has great characteristics such as good interlocking, strong resistance against waves and saving concrete. Through the hydraulic model test, the mechanism of stability of the block has been proved and the relations between stability and wave height, wave period, water depth, slope, laying method, porosity and cushion have been found. The effect of weight on steadiness have also been discovered. Finally, the method of design and some formulas are given.展开更多
To provide hexapod robots with strategies of locomotion planning, observation experiments were operated on a kind of ant with the use of high speed digital photography and computer assistant analysis. Through digitali...To provide hexapod robots with strategies of locomotion planning, observation experiments were operated on a kind of ant with the use of high speed digital photography and computer assistant analysis. Through digitalization of original analog video, locomotion characters of ants were obtained, the biomimetic foundation was laid for polynomial trajectory planning of multi-legged robots, which was deduced with mathematics method. In addition, five rules were concluded, which apply to hexapod robots marching locomotion planning. The first one is the fundamental strategy of multi-legged robots' leg trajectory planning. The second one helps to enhance the static and dynamic stability of multi-legged robots. The third one can improve the validity and feasibility of legs' falling points. The last two give criterions of multi-legged robots' toe trajectory figures and practical recommendatory constraints. These five rules give a good method for marching locomotion planning of multi-legged robots, and can be expended to turning planning and any other special locomotion.展开更多
AbstractBoth theoretical and experimental investigations are performed for a scheme for“ flutter taming”- semi-active control of structural nonlinear flutter. For atwo-dimensional nonlinear flutter system, a digital...AbstractBoth theoretical and experimental investigations are performed for a scheme for“ flutter taming”- semi-active control of structural nonlinear flutter. For atwo-dimensional nonlinear flutter system, a digital simulation method is used to verify theprinciple of semi-active flutter control and to study the response characteristics of theclosed loop flutter system. Simulation results show that by adjusting automatically thenonlinear stiffness parameter of the flutter system, the amphtude of the flutter responsecan be suppressed. In accordance with the theoretical analysis, a wind tunnel test model forsemi-active flutter control is designed. A micromotor-slide block system serves as theparameter control executive element with the monitoring of respf,are signal and the con-trolling of micromotor performed by a microcomputer. Wind tunnel tests confirm that thenonlinear flutter can be controlled effectively by this technique.展开更多
Tensile properties with different thermoforming conditions and deformation mechanism at thermoforming temperatures of automotive needlepunched carpets made up of three layers of different materials were reported.Inves...Tensile properties with different thermoforming conditions and deformation mechanism at thermoforming temperatures of automotive needlepunched carpets made up of three layers of different materials were reported.Investigations on the tensile properties were performed as a function of thermoforming temperature,extensile speed and fiber orientation based on an orthogonal experiment design.The experimental results show that the automotive carpets are rate-dependent anisotropic one and very sensitive to the forming temperature.The tensile properties are strongly depended on the forming temperature when compared with the extensile speed and the fiber orientation.Experiments only varying with the temperature were performed because of the dominative effect of the temperature.Different deformation performances were observed with different temperatures.Deformation mechanisms at the thermoforming temperatures were presented to explain the nonlinear trend of the ultimate elongation with the temperatures based on the combination of the experimental observations and the corresponding polymer theories.展开更多
Reburning technology is one of the most cost-effective NOx reduction strategies for coal combustion systems. In this paper, a nitric oxide submodel incorporated into a comprehensive coal combustion model was developed...Reburning technology is one of the most cost-effective NOx reduction strategies for coal combustion systems. In this paper, a nitric oxide submodel incorporated into a comprehensive coal combustion model was developed for predicting NOx reduction in a 93 kW laboratory-scale coal combustion furnace by reburning. This NO submodel, including reburning mechanism, requires the solution of only two transport equations to model the behavior of NO reduction in the reburning process. A number of experiments have been performed in the same furnace, and the experimental data obtained from the optimized reburn configuration was used to validate the model. Measurements and predictions both show above 50% reduction of NO emissions for the optimized reburning process. Profile comparisons show that the predicted temperature and oxygen concentration match well with the measurements, and the general trend of predicted NO concentration is very similar to that measured. The results of this study show that the present nitric oxide submodel depicts quite well the observed behaviour of NO annihilation in the reburning process. It is expected that this usable and computationally economic model represents a useful tool to simulate the gaseous fuel reburning process for the researchers concerned with practical combustors.展开更多
If the microcontrollers are devices quite easy to use for experts in electronics, a scientist devoted to different research topics from digital electronics is generally totally unable to develop and use these complex ...If the microcontrollers are devices quite easy to use for experts in electronics, a scientist devoted to different research topics from digital electronics is generally totally unable to develop and use these complex components. Most of the time, the researcher is looking for simple devices able to control different parameters during his experimentation. He is obliged in this case to request the intervention of an expert in electronics to develop such a device and the result is sometimes different from the precise initial requirement. Nowadays, it is possible to find on the market, simple units able to satisfy the requirements of the scientist and easy enough to be manipulated by him in specific applications. The purpose of this paper is to present some of these devices and to compare their possibilities and the ways to use them. These devices are compared in optically stimulated dosimetry with applications found in external dosimetry, interventional radiology, nuclear medicine and space dosimetry.展开更多
Three logarithmic linear equations between D_(Me)^(V/L) and [m_(NaCl)], and the relationship of D_(Me)^(V/L) versus F/Cl or K/Na mole ratios have been established by the experiments of the partitioning of Pb and Zn be...Three logarithmic linear equations between D_(Me)^(V/L) and [m_(NaCl)], and the relationship of D_(Me)^(V/L) versus F/Cl or K/Na mole ratios have been established by the experiments of the partitioning of Pb and Zn between granitic silicate melt and aqueous fluid. These results have been used to quantitatively study some essential problems, such as the possibility and degree of Pb-Zn mineralization in the system of granitic magma and hydrothermal fluid, and the influence of the relative contents of alkali and volatiles on the Pb-Zn mineralization in the same system. Some new points have been put forward in this paper.展开更多
in this paper, an experimental research the effect of ablating material on the reflection and the transmission of microwaves in arc-heated plasma flow is presented by using the C band microwave measuring system. The ...in this paper, an experimental research the effect of ablating material on the reflection and the transmission of microwaves in arc-heated plasma flow is presented by using the C band microwave measuring system. The results show that the ablating material with accidented surface and its high temperature have remarkably affected the reflection and the transmission of microwaves. The experiment proves that the system has outstanding precision and reliability.展开更多
With China’s entry into WTO and the opening-up of China’s economy to outside world,more foreign companies have flooded into China.And then English is playing a more and more important role in the world and in China....With China’s entry into WTO and the opening-up of China’s economy to outside world,more foreign companies have flooded into China.And then English is playing a more and more important role in the world and in China.ESP(English for Specific Purposes)also goes to the fastest growing area of English in China.Therefore,an experimental research on societal needs of EGP and ESP is conducted in this essay,whose results the teachers of ESP and EGP(English for General Purposes)can benefit from,such as designing syllabus and the courses,adopting and adapting materials,operating the classroom teaching,and evaluating the teaching process.Correspondingly,only by way of combining specific knowledge with learning skills can the students’English learning be really improved to sow the seeds of benefits for their future work and learning.展开更多
文摘Through the Latour concept of philosophy of science of laboratory life,the life course of a(geo)ethnographer researcher is analyzed,in order to establish the emotional or more personal dimensions that do not usually appear in research papers,but that have notable relevance in qualitative research.The text is structured in three large parts:A conceptual vision of the new experimental geography;the experimental geo-ethnography in old social,new social and place scenarios;and finally,the most personal and emotional dimension of the research.The first part establishes the geo-ethnographic experimental context and the assumptions in fieldwork,in addition to the geo-ethnographic reconciliation process.In the second part,the main qualitative research problems related to mobility,resistance and dynamics in place are established.Finally,in the third part the research perceptions,the personal experiences,and the emotional dimension of the research in remote rural areas are established.The laboratory life of a researcher,allows one to establish scalar conclusions and rigor in qualitative research.
基金supported by the National Natural Science Foundation of China (Grant number 51776015)
文摘In view of the importance of gas-liquid two-phase spiral flow and the few research reports at home and abroad,the gas-liquid two-phase spiral flow patterns have been researched in a horizontal pipe with different parameters investigated by means of observation and a high-speed camera.Since the appearance of spiral flow makes the distribution of twophase flow more complicated,the flow patterns appearing in the experiments were divided into the Spiral Wavy Stratified Flow(SWS),the Spiral Bubble Flow(SB),the Spiral Slug Flow(SS),the Spiral Linear Flow(SL),the Spiral Axial Flow(SA),and the Spiral Dispersed Flow(SD) by the observations and with reference to the predecessors' research achievements.A flow pattern map has been drawn up.The influence of velocity,vane angle and vane area on flow pattern conversion boundary and pressure drop has been studied,with a solid foundation laid for the future research work.
文摘The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendliness.The heat storage process of the Ca(OH)_(2)/CaO TCES system in a mixed heating reactor was evaluated in this study,by employing a combination of direct and indirect heating modes.The dehydration process was studied experimentally,and a numerical model was established and verified based on the experimental results.The dehydration behavior of 500 g of Ca(OH)_(2) powder was investigated in a fixed-bed reactor with mixed heating.The experimental and simulation results indicated that mixed heating causes combined centripetal and horizontal propulsion.Heat input is the main limiting factor in the heat storage process,because the radial advance of the reaction is hindered by the low thermal conductivity of the solid reactant particles.Heat transmission partitions were added to enhance the performance of the reactor.The performance of the modified reactor was compared with that of a conventional reactor.The radial heat transmission partitions in the modified reactor effectively enhance the energy storage rate and reduce the reaction time by 59.5%compared with the reactor without partitions.
基金This project is supported by National Key Technologies R&D Programme,China (No.2001BA501A22).
文摘The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, distance of fin space, frost, and velocity of air flow etc. They mainly influence the thermal efficiency of an evaporator, and therefore its thermal efficiency has direct relationship with the whole efficiency of the quick freeze plant. Evaporators with different structural types have different heat transfer efficiency, in order to obtain high efficiency structure of evaporator, 8 evaporator models with different fin shape, tube diameter and tube arrangement are analyzed and compared. The calculation results show that the integral waved fins, equilateral-triangle arranged small diameter tubes and varying fin-spacing has the highest heat transfer coefficient. The experimental result also shows that the evaporator with this type of structure has better thermal efficiency. The experimental result is in good agreement with the calculation result, it can instruct engineering design for usual designer. A real quick-freeze equipment is designed and put into production. The result shows that, compared with traditional domestic quick-freeze equipments, this equipment decreases by 40% in size and by 20% in energy consumption.
文摘The absence of effective therapies for castration-resistant prostate cancer(CRPC) establishes the need to develop novel therapeutic modality, such as targeted gene therapy, which is ideal for the treatment of CRPC. But its application has been limited due to lack of favorable gene vector and the reduction of "bystander effect". Consequently, scientists all over the world focus their main experimental research on the following four aspects: targeted gene, vector, transfer means and comprehensive therapy. In this paper, we reviewed the latest advances of experimental research on targeted gene therapy for prostate cancer.
文摘Polysocoharibe-peptide of Coriolus Versicolor (PSP) is a new anti-cancer immunomodulative drug. The present paper reports on the experimental research done with this drug. It was found that PSP had the ability to recover hemolysin HC50, to increase the weight of the thymus, and increase the alexin of serum C3 and the IgG content of tumor bearing mice. FSP also significantly raised the pha-gocytic activity of macrophages in normal mice. PSP had a significant inhibitory effect on P38S and S180 cells. At the concentration of 1 mg/ml, PSP inhibited the proliferating activity of some human tumor call lines, such as SGC 7901, SPC, SLY and Mei. It had a direct toxic effect on SPC cells. PSP significantly inhibited the synthesis of nucleic acids of Ehrlich ascites carcinoma cells. In addition, PSP was antagonistic to the side effects of chemotherapy and radiotherapy.
文摘?Fundamental experiments on lower hybrid current drive (LHCD) have been undertaken on HT-7 superconducting tokamak. The experiments on LHCD efficiency reveal its depen- deuce on plasma density and the toroidal magnetic field. Furthermore, the experiments on HT-7 successfully demonstrate the ability for LHCD to sustain long pulse tokamak discharges, such as discharges with full non-inductive current drive for several seconds. The experimental study to improve plasma confinements by LHCD suggests that the improvement should be due to the change o f current profile. It has also been demonstrated by the experiments that the lower hybrid wave may lead to an enhanced ionization of particles in the region where the wave is deposited.
基金Supported by the National Natural Science Foundation of China under Grant No 61306076
文摘The calculated and experimental research of sheet resistances of crystalline silicon solar cells by dry laser doping is investigated. The nonlinear numerical model on laser melting of crystalline silicon and liquid-phase diffusion of phosphorus atoms by dry laser doping is analyzed by the finite difference method implemented in MATLAB. The melting period and melting depth of crystalline silicon as a function of laser energy density is achieved. The effective liquid-phase diffusion of phosphorus atoms in melting silicon by dry laser doping is confirmed by the rapid decrease of sheet resistances in experimental measurement. The plateau of sheet resistances is reached at around 15 Ω/. The calculated sheet resistances as a function of laser energy density is obtained and the calculated results are in good agreement with the corresponding experimental measurement. Due to the successful verification by comparison between experimental measurement and calculated results, the simulation results could be used to optimize the virtual laser doping parameters.
基金sponsored by National Defence Researching Fund(9140c300202120c30)the Fundamental Research Fund for the central Universities(30920130112007)
文摘In order to study the propagation mechanism of continuous rotating detonation wave,the H2/air continuous rotating detonation engine ignited by tangentially installed H2/O2pre-detonation tube is studied experimentally using a tilt slot injector structure.The experimental results show that the stable rotating detonation wave can be gained successfully with the equivalent ratio of 0.93.The propagation frequency and velocity of rotating detonation wave range from 5200 to 5500 Hz and from 1518.5 to 1606.1 m/s,respectively.Three propagation modes,such as rotation,reversal and bifurcation,of detonation wave are verified through the analysis of propagation mechanism of rotating detonation wave.
基金Education and Teaching Reform Project of Central South University(2019jy097).
文摘At present,rail transit is developing rapidly in the world,and this means new and changing requirements for the training of talents in railway engineering experiments.Given the current problems of limited laboratory/field instruments for railway engineering experimentsand the safety/administrative difficulties of going to the frontline of railway lines to teach railway engineering experiemnts in the field,the Department of Railway Engineering of Central South University tried to introduce virtual reality(VR)technology to teach students experiments in the field of railway engineering.Through the virtualized experimental methods,students can carry out railway engineering experiments such as;vehicle wheel pair off-axis experiments,track geometry and position detection,etc.by immersive means.It was observed that after performing virtual simulation experiments,students appeared conversant in subsequent field experiments.Thus,VR greatly improves the teaching efficiency of railway engineering experiments.
文摘This paper introduces a new kind of armour block - hexagon multihole block on sloping breakwater. It has great characteristics such as good interlocking, strong resistance against waves and saving concrete. Through the hydraulic model test, the mechanism of stability of the block has been proved and the relations between stability and wave height, wave period, water depth, slope, laying method, porosity and cushion have been found. The effect of weight on steadiness have also been discovered. Finally, the method of design and some formulas are given.
基金Sponsored by the Ministerial Level Advanced Research Foundation(65822576)
文摘To provide hexapod robots with strategies of locomotion planning, observation experiments were operated on a kind of ant with the use of high speed digital photography and computer assistant analysis. Through digitalization of original analog video, locomotion characters of ants were obtained, the biomimetic foundation was laid for polynomial trajectory planning of multi-legged robots, which was deduced with mathematics method. In addition, five rules were concluded, which apply to hexapod robots marching locomotion planning. The first one is the fundamental strategy of multi-legged robots' leg trajectory planning. The second one helps to enhance the static and dynamic stability of multi-legged robots. The third one can improve the validity and feasibility of legs' falling points. The last two give criterions of multi-legged robots' toe trajectory figures and practical recommendatory constraints. These five rules give a good method for marching locomotion planning of multi-legged robots, and can be expended to turning planning and any other special locomotion.
文摘AbstractBoth theoretical and experimental investigations are performed for a scheme for“ flutter taming”- semi-active control of structural nonlinear flutter. For atwo-dimensional nonlinear flutter system, a digital simulation method is used to verify theprinciple of semi-active flutter control and to study the response characteristics of theclosed loop flutter system. Simulation results show that by adjusting automatically thenonlinear stiffness parameter of the flutter system, the amphtude of the flutter responsecan be suppressed. In accordance with the theoretical analysis, a wind tunnel test model forsemi-active flutter control is designed. A micromotor-slide block system serves as theparameter control executive element with the monitoring of respf,are signal and the con-trolling of micromotor performed by a microcomputer. Wind tunnel tests confirm that thenonlinear flutter can be controlled effectively by this technique.
基金Supported by National Natural Science Foundation of China(No.50305020)
文摘Tensile properties with different thermoforming conditions and deformation mechanism at thermoforming temperatures of automotive needlepunched carpets made up of three layers of different materials were reported.Investigations on the tensile properties were performed as a function of thermoforming temperature,extensile speed and fiber orientation based on an orthogonal experiment design.The experimental results show that the automotive carpets are rate-dependent anisotropic one and very sensitive to the forming temperature.The tensile properties are strongly depended on the forming temperature when compared with the extensile speed and the fiber orientation.Experiments only varying with the temperature were performed because of the dominative effect of the temperature.Different deformation performances were observed with different temperatures.Deformation mechanisms at the thermoforming temperatures were presented to explain the nonlinear trend of the ultimate elongation with the temperatures based on the combination of the experimental observations and the corresponding polymer theories.
基金Project 2004CB217704-4 supported by the Special Funds for Major State Basic Research Projects of China and 306012 by the Key Grant Project of Chinese Ministry of Education
文摘Reburning technology is one of the most cost-effective NOx reduction strategies for coal combustion systems. In this paper, a nitric oxide submodel incorporated into a comprehensive coal combustion model was developed for predicting NOx reduction in a 93 kW laboratory-scale coal combustion furnace by reburning. This NO submodel, including reburning mechanism, requires the solution of only two transport equations to model the behavior of NO reduction in the reburning process. A number of experiments have been performed in the same furnace, and the experimental data obtained from the optimized reburn configuration was used to validate the model. Measurements and predictions both show above 50% reduction of NO emissions for the optimized reburning process. Profile comparisons show that the predicted temperature and oxygen concentration match well with the measurements, and the general trend of predicted NO concentration is very similar to that measured. The results of this study show that the present nitric oxide submodel depicts quite well the observed behaviour of NO annihilation in the reburning process. It is expected that this usable and computationally economic model represents a useful tool to simulate the gaseous fuel reburning process for the researchers concerned with practical combustors.
文摘If the microcontrollers are devices quite easy to use for experts in electronics, a scientist devoted to different research topics from digital electronics is generally totally unable to develop and use these complex components. Most of the time, the researcher is looking for simple devices able to control different parameters during his experimentation. He is obliged in this case to request the intervention of an expert in electronics to develop such a device and the result is sometimes different from the precise initial requirement. Nowadays, it is possible to find on the market, simple units able to satisfy the requirements of the scientist and easy enough to be manipulated by him in specific applications. The purpose of this paper is to present some of these devices and to compare their possibilities and the ways to use them. These devices are compared in optically stimulated dosimetry with applications found in external dosimetry, interventional radiology, nuclear medicine and space dosimetry.
文摘Three logarithmic linear equations between D_(Me)^(V/L) and [m_(NaCl)], and the relationship of D_(Me)^(V/L) versus F/Cl or K/Na mole ratios have been established by the experiments of the partitioning of Pb and Zn between granitic silicate melt and aqueous fluid. These results have been used to quantitatively study some essential problems, such as the possibility and degree of Pb-Zn mineralization in the system of granitic magma and hydrothermal fluid, and the influence of the relative contents of alkali and volatiles on the Pb-Zn mineralization in the same system. Some new points have been put forward in this paper.
文摘in this paper, an experimental research the effect of ablating material on the reflection and the transmission of microwaves in arc-heated plasma flow is presented by using the C band microwave measuring system. The results show that the ablating material with accidented surface and its high temperature have remarkably affected the reflection and the transmission of microwaves. The experiment proves that the system has outstanding precision and reliability.
文摘With China’s entry into WTO and the opening-up of China’s economy to outside world,more foreign companies have flooded into China.And then English is playing a more and more important role in the world and in China.ESP(English for Specific Purposes)also goes to the fastest growing area of English in China.Therefore,an experimental research on societal needs of EGP and ESP is conducted in this essay,whose results the teachers of ESP and EGP(English for General Purposes)can benefit from,such as designing syllabus and the courses,adopting and adapting materials,operating the classroom teaching,and evaluating the teaching process.Correspondingly,only by way of combining specific knowledge with learning skills can the students’English learning be really improved to sow the seeds of benefits for their future work and learning.