Intangible cultural heritage is given new life as antique books,paintings,and calligraphies get restored.Acrucial reason that traditions and cultures can be passed down from generation to generation is because tangibl...Intangible cultural heritage is given new life as antique books,paintings,and calligraphies get restored.Acrucial reason that traditions and cultures can be passed down from generation to generation is because tangible cultural products such as paintings,calligraphies,and展开更多
第一部分语言基础(共两节,满分24分)第一节单句填空(共15小题;每小题1分,满分15分)1. One interesting aspect of this bilingual series is that it caters to both the domestic and foreign markets, especially in reading for both...第一部分语言基础(共两节,满分24分)第一节单句填空(共15小题;每小题1分,满分15分)1. One interesting aspect of this bilingual series is that it caters to both the domestic and foreign markets, especially in reading for both____(pleasant) and language learning.2. As is known to us,____(curtain) are large pieces of material which hang from the top of a window.展开更多
1Art Market Issue 5,2023 Interpreting the Guqin Cultural Code This year marks the 20th anniversary of the inclusion of the Chinese Guqin art in the Masterpieces of the Oral and Intangible Heritage of Humanity. At pres...1Art Market Issue 5,2023 Interpreting the Guqin Cultural Code This year marks the 20th anniversary of the inclusion of the Chinese Guqin art in the Masterpieces of the Oral and Intangible Heritage of Humanity. At present, with the rise of "guochao" (the rising cultural tide in China) in Chinese society, learning Guqin has become a fashion.展开更多
The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social lands...The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social landscapes over the 600 years.展开更多
New techniques and designs rejuvenate the traditional Tibetan tapestry-weaving craft Apiece of Tibetan tapestry with images of three angels stood out when Tanzin Chinleh live-streamed to introduce the products in his ...New techniques and designs rejuvenate the traditional Tibetan tapestry-weaving craft Apiece of Tibetan tapestry with images of three angels stood out when Tanzin Chinleh live-streamed to introduce the products in his store on February 11.“It is a tailored handmade product we are going to promote this year,”the 32-year-old told viewers.展开更多
In this article, researches on improvement of 1RX regenerator used in cleaning processes of cotton ginning enterprises were carried out. The effect of changing the parameters of the new working body—rubber-plate drum...In this article, researches on improvement of 1RX regenerator used in cleaning processes of cotton ginning enterprises were carried out. The effect of changing the parameters of the new working body—rubber-plate drum and machine inlet on the efficiency of cotton separation was studied in the research, and the maximum level of efficiency of separation was determined. In this paper work, the main factors affecting the efficient operation of the regenerator were identified, their value limits were determined, and research was conducted using the mathematical planning method. As a result, effective operation of the improved 1RX cotton regenerator was observed at the value of the given factors, that is, the separation efficiency was 99.5%, the cleaning efficiency was higher than 88.7%, and the amount of seed cotton in the waste was reduced lower than 2.5%.展开更多
In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining ope...In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.展开更多
Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the...Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the drug spot check of Chinese herbal pieces based on the data of drug quality published by the National Medical Products Administration from 2013 to 2021,combined with the current provisions and implementation of drug spot check management in China.Results and Conclusion At present,there are some problems in the drug spot check of Chinese herbal pieces,such as fewer varieties of Chinese herbal pieces in the national drug spot check,the unreasonable sampling links,the insufficient territorial management in some areas,and error-prone sample extraction.It is suggested that the actual quantity and overall quality of Chinese herbal pieces should be fully considered in the formulation of sampling plan.Besides,the variety coverage of drug spot check of traditional Chinese medicine should be strengthened.In the planning,the sampling links shall be made as a whole,and the credit rating and distribution of drug production,operation and use units within the jurisdiction shall be fully combined.While strengthening the sampling management at the production end in areas with concentrated industries,regional special drug spot check should be carried out or the administrative forces at the provincial,municipal and county levels should be fully mobilized to avoid local protection.In the assigned tasks,the name of Chinese herbal pieces should be accurately expressed to avoid the sampling errors of Chinese herbal pieces with the same original medicinal materials and different processing methods.展开更多
The Song of Solomon is a series of love poems which contain 6 pieces of love poems and most part in the form of songs addressed by a man to a woman, and by the woman to the man, in order to express the love between th...The Song of Solomon is a series of love poems which contain 6 pieces of love poems and most part in the form of songs addressed by a man to a woman, and by the woman to the man, in order to express the love between them.Figures of speech are ways of making our language figurative. They can be divided into three parts, they are syntactical, semantic and phonetic rhetorical devices. These rhetorical devices can help us to heighten effect and to make the writing figuratively and vividly.These figures of speech used in the Song of Solomon make great contribution to the success description of these long songs.This essay will center on the figures of speech in the Song of Solomon.展开更多
This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybr...This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybrid calibration method for laser scanning is proposed to improve convenience and precision.This method includes an integrative method for data collection and a hybrid algorithm for data processing.The integrative method conveniently collects a substantial number of calibrating points with a stepped gauge and a pattern for both the translation and rotation scans.The hybrid algorithm,which consists of a basic model and a compensation network,achieves strong stability with a small degree of errors.The experiments verified the hybrid calibration method and the scanner application for the measurement of dental pieces.Two typical dental pieces were measured,and the experimental results demonstrated the validity of the measurement that was performed using the dual-platform scanner.This method is effective for the 3D reconstruction of dental pieces,as well as that of objects with irregular shapes in engineering fields.展开更多
Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and c...Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.展开更多
The heat transfer theory is used to set up the mathematical model to calculate the process thermal cycle of steel ingot, steel slab and steel piece. The finite difference method is used to set up difference equation t...The heat transfer theory is used to set up the mathematical model to calculate the process thermal cycle of steel ingot, steel slab and steel piece. The finite difference method is used to set up difference equation to calculate the heat transfer process. Using initial condition and boundary condition during thermal cycle, the iteration method is used to calculate the difference equation The varying law of temperature distribution with furnace temperature and heating time are obtained in the heating process of steel ingot, steel slab and in the annealing process of steel piece. The heating process of GCr15 steel ingot, M2 steel slab in re-heating furnace and the annealing process of H13 steel piece in the roller bottom furnace are designed. The new process is already used in production. Comparing with old process, practice has proved that the new process is scientific and reasonable, and meets the requirements of production. The new process can save energy and raise the productivity. The new processes win eulogy of the producer.展开更多
In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without ...In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.展开更多
文摘Intangible cultural heritage is given new life as antique books,paintings,and calligraphies get restored.Acrucial reason that traditions and cultures can be passed down from generation to generation is because tangible cultural products such as paintings,calligraphies,and
文摘第一部分语言基础(共两节,满分24分)第一节单句填空(共15小题;每小题1分,满分15分)1. One interesting aspect of this bilingual series is that it caters to both the domestic and foreign markets, especially in reading for both____(pleasant) and language learning.2. As is known to us,____(curtain) are large pieces of material which hang from the top of a window.
文摘1Art Market Issue 5,2023 Interpreting the Guqin Cultural Code This year marks the 20th anniversary of the inclusion of the Chinese Guqin art in the Masterpieces of the Oral and Intangible Heritage of Humanity. At present, with the rise of "guochao" (the rising cultural tide in China) in Chinese society, learning Guqin has become a fashion.
文摘The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social landscapes over the 600 years.
文摘New techniques and designs rejuvenate the traditional Tibetan tapestry-weaving craft Apiece of Tibetan tapestry with images of three angels stood out when Tanzin Chinleh live-streamed to introduce the products in his store on February 11.“It is a tailored handmade product we are going to promote this year,”the 32-year-old told viewers.
文摘In this article, researches on improvement of 1RX regenerator used in cleaning processes of cotton ginning enterprises were carried out. The effect of changing the parameters of the new working body—rubber-plate drum and machine inlet on the efficiency of cotton separation was studied in the research, and the maximum level of efficiency of separation was determined. In this paper work, the main factors affecting the efficient operation of the regenerator were identified, their value limits were determined, and research was conducted using the mathematical planning method. As a result, effective operation of the improved 1RX cotton regenerator was observed at the value of the given factors, that is, the separation efficiency was 99.5%, the cleaning efficiency was higher than 88.7%, and the amount of seed cotton in the waste was reduced lower than 2.5%.
基金The financial support of National Natural Science Foundation of China(Grant Nos.52175108,51805352)is gratefully acknowledgedWe also would like to acknowledge the Key Research and Development Project of Shanxi Province(Grant No.202102010101009).
文摘In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.
文摘Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the drug spot check of Chinese herbal pieces based on the data of drug quality published by the National Medical Products Administration from 2013 to 2021,combined with the current provisions and implementation of drug spot check management in China.Results and Conclusion At present,there are some problems in the drug spot check of Chinese herbal pieces,such as fewer varieties of Chinese herbal pieces in the national drug spot check,the unreasonable sampling links,the insufficient territorial management in some areas,and error-prone sample extraction.It is suggested that the actual quantity and overall quality of Chinese herbal pieces should be fully considered in the formulation of sampling plan.Besides,the variety coverage of drug spot check of traditional Chinese medicine should be strengthened.In the planning,the sampling links shall be made as a whole,and the credit rating and distribution of drug production,operation and use units within the jurisdiction shall be fully combined.While strengthening the sampling management at the production end in areas with concentrated industries,regional special drug spot check should be carried out or the administrative forces at the provincial,municipal and county levels should be fully mobilized to avoid local protection.In the assigned tasks,the name of Chinese herbal pieces should be accurately expressed to avoid the sampling errors of Chinese herbal pieces with the same original medicinal materials and different processing methods.
文摘The Song of Solomon is a series of love poems which contain 6 pieces of love poems and most part in the form of songs addressed by a man to a woman, and by the woman to the man, in order to express the love between them.Figures of speech are ways of making our language figurative. They can be divided into three parts, they are syntactical, semantic and phonetic rhetorical devices. These rhetorical devices can help us to heighten effect and to make the writing figuratively and vividly.These figures of speech used in the Song of Solomon make great contribution to the success description of these long songs.This essay will center on the figures of speech in the Song of Solomon.
基金the National Science Fund for Excellent Young Scholars(51722509)the National Natural Science Foundation of China(51575440)+1 种基金the National Key R&D Program of China(2017YFB1104700)the Shaanxi Science and Technology Project(2016GY-011)。
文摘This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybrid calibration method for laser scanning is proposed to improve convenience and precision.This method includes an integrative method for data collection and a hybrid algorithm for data processing.The integrative method conveniently collects a substantial number of calibrating points with a stepped gauge and a pattern for both the translation and rotation scans.The hybrid algorithm,which consists of a basic model and a compensation network,achieves strong stability with a small degree of errors.The experiments verified the hybrid calibration method and the scanner application for the measurement of dental pieces.Two typical dental pieces were measured,and the experimental results demonstrated the validity of the measurement that was performed using the dual-platform scanner.This method is effective for the 3D reconstruction of dental pieces,as well as that of objects with irregular shapes in engineering fields.
基金Supported by National Nature Science Foundation of China(Grant No.51175461)Science Fund for Creative Research Groups of National Natural Science Foundation of China(Grant No.51221004)Program for Zhejiang Leading Team of S&T Innovation of China(Grant No.2009R50008)
文摘Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.
文摘The heat transfer theory is used to set up the mathematical model to calculate the process thermal cycle of steel ingot, steel slab and steel piece. The finite difference method is used to set up difference equation to calculate the heat transfer process. Using initial condition and boundary condition during thermal cycle, the iteration method is used to calculate the difference equation The varying law of temperature distribution with furnace temperature and heating time are obtained in the heating process of steel ingot, steel slab and in the annealing process of steel piece. The heating process of GCr15 steel ingot, M2 steel slab in re-heating furnace and the annealing process of H13 steel piece in the roller bottom furnace are designed. The new process is already used in production. Comparing with old process, practice has proved that the new process is scientific and reasonable, and meets the requirements of production. The new process can save energy and raise the productivity. The new processes win eulogy of the producer.
文摘In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.
