This paper presents the design and verification of the dual-mode core driven fan stage(CDFS)and high-load compressor with a large flow regulation range.In view of the characteristics of large flow regulation range of ...This paper presents the design and verification of the dual-mode core driven fan stage(CDFS)and high-load compressor with a large flow regulation range.In view of the characteristics of large flow regulation range of the two modes and high average stage load coefficient,this paper investigates the design technology of the dual-mode high-efficiency compressor with a large flow regulation range and high-load compressor with an average stage load coefficient of 0.504.Building upon this research,the design of the dual-mode CDFS and four-stage compressor is completed,and three-dimensional numerical simulation of the two modes is carried out.Finally,performance experiment is conducted to verify the result of three-dimensional numerical simulation.The experiment results show that the compressor performance is improved for the whole working conditions by using the new design method,which realizes the complete fusion design of the CDFS and high-pressure compressor(HPC).The matching mechanism of stage characteristics of single and double bypass modes and the variation rule of different adjustment angles on performance are studied comprehensively.Furthermore,it effectively reduces the length and weight of compressor,and breaks through the key technologies such as high-load compressor with the average load factor of 0.504.These findings provide valuable data and a methodological foundation for the development of the next generation aeroengine.展开更多
This paper carefully probes into the main models of the bilingual education in the world, deeply analyses the conditions and requirements on the implementation of the bilingual education in our schools, and clearly di...This paper carefully probes into the main models of the bilingual education in the world, deeply analyses the conditions and requirements on the implementation of the bilingual education in our schools, and clearly differentiates TEFL and TESL as well as bilingual education. The writer thinks that in China we teach English as a foreign language instead of a second language, that the bilingual education is the supreme level of the foreign language acquisition, and that the final goal of the bilingual education is to make learners simultaneously think and use Chinese and English in both ways as well as communicate with one another in two languages according to the situational context. Therefore, it is not easy to practice the bilingual education in a country like China, which is still poor in the English language context. But the situation will change as China enters WTO and the globalization speeds up.展开更多
In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on al...In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.展开更多
In this paper two new species of Rondaniella Johannsen, 1909 from China are described. The type specimens are deposited in Zhejiang Forestry College, China.
A single CMOS image sensor based on a 0.35μm process along with its design and implementation is introduced. The architecture of an active pixel sensor is used in the chip. The fill factor of a pixel cell can reach 4...A single CMOS image sensor based on a 0.35μm process along with its design and implementation is introduced. The architecture of an active pixel sensor is used in the chip. The fill factor of a pixel cell can reach 43%,higher than the traditional factor of 30%. Moreover, compared with the conventional method whose fixed pattern noise （FPN） is around 0.5%, a dynamic digital double sampling technique is developed, which possesses simpler circuit architecture and a better FPN suppression outcome. The CMOS image sensor chip is implemented in the 0.35μm mixed signal process of a Chartered by MPW. The experimental results show that the chip operates welt,with an FPN of about 0.17%.展开更多
Dual-modulus prescalers （DMP） for RF receivers are studied. An improved D-latch is proposed to increase the speed and the driving capability of the DMP. A novel D-latch architecture integrated with ‘OR＇ logic is p...Dual-modulus prescalers （DMP） for RF receivers are studied. An improved D-latch is proposed to increase the speed and the driving capability of the DMP. A novel D-latch architecture integrated with ‘OR＇ logic is proposed to decrease the complexity of the circuit. A divided-by-16/17 DMP for application in a digital video broadcasting-terrestrial receiver is realized with a TSMC 0.18μm mixed-signal CMOS process. The programmable ＆ pulse swallow divider in this receiver is designed with a 0.18μm CMOS standard cell library and realized in the same process. The measured results show that the DMP has an output jitter of less than 0.03% and works well with the programmable ＆ pulse swallow divider.展开更多
Bilingual education is one of Chinese education directions in the 21st century. And constructivism is the educational foundation of bilingual education. This paper presents a study of teaching theory and the pattern o...Bilingual education is one of Chinese education directions in the 21st century. And constructivism is the educational foundation of bilingual education. This paper presents a study of teaching theory and the pattern of bilingual education. The current situation and the development of bilingual education are discussed as well.展开更多
Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+she...Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.展开更多
Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,s...Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,suchas sub-Poissonian statistics and intermode correlation.We propose schemes to generate two-mode circular states by theinteraction of a trapped ion with traveling wave lasers.展开更多
A new multi-step adaptive predictive control algorithm for a class of bilinear systems is presented. The structure of the bilinear system is converted into a simple linear model by using nonlinear support vector machi...A new multi-step adaptive predictive control algorithm for a class of bilinear systems is presented. The structure of the bilinear system is converted into a simple linear model by using nonlinear support vector machine (SVM) dynamic approximation with analytical control law derived. The method does not need on-line parameters estimation because the system’s internal model has been transformed into an off-line global model. Compared with other traditional methods, this control law reduces on-line parameter estimating burden. In addition, its overall linear behavior treating method allows an analytical control law available and avoids on-line nonlinear optimization. Simulation results are presented in the article to illustrate the efficiency of the method.展开更多
文摘This paper presents the design and verification of the dual-mode core driven fan stage(CDFS)and high-load compressor with a large flow regulation range.In view of the characteristics of large flow regulation range of the two modes and high average stage load coefficient,this paper investigates the design technology of the dual-mode high-efficiency compressor with a large flow regulation range and high-load compressor with an average stage load coefficient of 0.504.Building upon this research,the design of the dual-mode CDFS and four-stage compressor is completed,and three-dimensional numerical simulation of the two modes is carried out.Finally,performance experiment is conducted to verify the result of three-dimensional numerical simulation.The experiment results show that the compressor performance is improved for the whole working conditions by using the new design method,which realizes the complete fusion design of the CDFS and high-pressure compressor(HPC).The matching mechanism of stage characteristics of single and double bypass modes and the variation rule of different adjustment angles on performance are studied comprehensively.Furthermore,it effectively reduces the length and weight of compressor,and breaks through the key technologies such as high-load compressor with the average load factor of 0.504.These findings provide valuable data and a methodological foundation for the development of the next generation aeroengine.
文摘This paper carefully probes into the main models of the bilingual education in the world, deeply analyses the conditions and requirements on the implementation of the bilingual education in our schools, and clearly differentiates TEFL and TESL as well as bilingual education. The writer thinks that in China we teach English as a foreign language instead of a second language, that the bilingual education is the supreme level of the foreign language acquisition, and that the final goal of the bilingual education is to make learners simultaneously think and use Chinese and English in both ways as well as communicate with one another in two languages according to the situational context. Therefore, it is not easy to practice the bilingual education in a country like China, which is still poor in the English language context. But the situation will change as China enters WTO and the globalization speeds up.
文摘In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.
基金The project was supported by the Natural Science Foundation of China (30070102)
文摘In this paper two new species of Rondaniella Johannsen, 1909 from China are described. The type specimens are deposited in Zhejiang Forestry College, China.
文摘A single CMOS image sensor based on a 0.35μm process along with its design and implementation is introduced. The architecture of an active pixel sensor is used in the chip. The fill factor of a pixel cell can reach 43%,higher than the traditional factor of 30%. Moreover, compared with the conventional method whose fixed pattern noise （FPN） is around 0.5%, a dynamic digital double sampling technique is developed, which possesses simpler circuit architecture and a better FPN suppression outcome. The CMOS image sensor chip is implemented in the 0.35μm mixed signal process of a Chartered by MPW. The experimental results show that the chip operates welt,with an FPN of about 0.17%.
文摘Dual-modulus prescalers （DMP） for RF receivers are studied. An improved D-latch is proposed to increase the speed and the driving capability of the DMP. A novel D-latch architecture integrated with ‘OR＇ logic is proposed to decrease the complexity of the circuit. A divided-by-16/17 DMP for application in a digital video broadcasting-terrestrial receiver is realized with a TSMC 0.18μm mixed-signal CMOS process. The programmable ＆ pulse swallow divider in this receiver is designed with a 0.18μm CMOS standard cell library and realized in the same process. The measured results show that the DMP has an output jitter of less than 0.03% and works well with the programmable ＆ pulse swallow divider.
文摘Bilingual education is one of Chinese education directions in the 21st century. And constructivism is the educational foundation of bilingual education. This paper presents a study of teaching theory and the pattern of bilingual education. The current situation and the development of bilingual education are discussed as well.
基金Project(51874129)supported by the National Natural Science Foundation of ChinaProjects(2018JJ3115,2019JJ60049)supported by the Science Foundation of Hunan Province,ChinaProjects(19B153,19B158)supported by the Scientific Research Fund of Hunan Provincial Education Department,China。
文摘Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.
基金supported by the Natural Science Foundation of the Education Committee of Anhui Province of China under Grant No.JK2008A029
文摘Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,suchas sub-Poissonian statistics and intermode correlation.We propose schemes to generate two-mode circular states by theinteraction of a trapped ion with traveling wave lasers.
基金Project (No. 60421002) supported by the National Natural ScienceFoundation of China
文摘A new multi-step adaptive predictive control algorithm for a class of bilinear systems is presented. The structure of the bilinear system is converted into a simple linear model by using nonlinear support vector machine (SVM) dynamic approximation with analytical control law derived. The method does not need on-line parameters estimation because the system’s internal model has been transformed into an off-line global model. Compared with other traditional methods, this control law reduces on-line parameter estimating burden. In addition, its overall linear behavior treating method allows an analytical control law available and avoids on-line nonlinear optimization. Simulation results are presented in the article to illustrate the efficiency of the method.
