The awareness of applying genre in teaching and learning language has been aroused recently, and the choices of genres are connected closely with teachers' teaching goals and the needs of students. This paper whic...The awareness of applying genre in teaching and learning language has been aroused recently, and the choices of genres are connected closely with teachers' teaching goals and the needs of students. This paper which holds certain pedagogic purpose, analyzes genre-based teaching approach via an analysis on an English text book named Changes (level 1), aiming to help EFL teachers cultivate their genre awareness.展开更多
During recent years,some notions about tasks have been considered as the major part of analysis in different teaching approaches and teachers are being more interested in the use of taskbased approach both in foreign ...During recent years,some notions about tasks have been considered as the major part of analysis in different teaching approaches and teachers are being more interested in the use of taskbased approach both in foreign and in second language teaching.The main goal of this article is to introduce and discuss some major principles of task-based language teaching and indicates how teachers can apply them in their curriculum.展开更多
There are several teaching approaches being used to instruct the reading and writing teaching, such as the product approach, the process approach and the genre approach. In a long period, the product approach and the ...There are several teaching approaches being used to instruct the reading and writing teaching, such as the product approach, the process approach and the genre approach. In a long period, the product approach and the process approach dominate the field of writing teaching. With the development of genre and genre-analysis theory, we begin to realize that genre-based approach is effective in improving students ’ reading comprehension and writing. Based on the analysis of the theory and on the present situations of college English teaching and personal teaching experience, the genre-based teaching approach is introduced to the writing and reading comprehension teaching.展开更多
Task-based language teaching approach(TBLTA), which lays stress on "learning by doing", gained increasing popularity in English teaching in recent years. The design of phonetic teaching calls for more emphas...Task-based language teaching approach(TBLTA), which lays stress on "learning by doing", gained increasing popularity in English teaching in recent years. The design of phonetic teaching calls for more emphasis from English educators since it is one of the basic rounds of English teaching. This paper made a trial on the utilization of TBLTA in the English phonetic teaching context and designed a TBLTA model for English phonetic teaching based on discussions about model and merits of TBLTA.展开更多
Insufficient vocabulary has become a barrier to reading comprehension and translation in the process of ME (medical English) study to the third-year students at medical universities or colleges. The current study was ...Insufficient vocabulary has become a barrier to reading comprehension and translation in the process of ME (medical English) study to the third-year students at medical universities or colleges. The current study was designed to investigate corpus-based teaching ap-proach to enlarging students'vocabulary in the course of higher learning of ML (medical literature). The study was carried out from 2006.9 to 2008.9 among third-year medical students in our college. Students were encouraged to augment their vocabulary by active practice,intensive learning,and comprehensive learning respectively through discovering study by using self-made ME corpuses (90,000 words). In doing so,their vocabulary was enlarged by actively using the essential vocabulary,attaching more attention to the difficult technical vocabulary,and getting familiar with medical terms,which eliminated their language barrier,improved their integrated language proficiency,and developed their sense of achievement.展开更多
This paper presents a Model-Based Design(MBD)approach for the design and control of a customized manipulator intended for drilling and position-ing of dental implants accurately with minimal human intervention.While p...This paper presents a Model-Based Design(MBD)approach for the design and control of a customized manipulator intended for drilling and position-ing of dental implants accurately with minimal human intervention.While performing an intra-oral surgery for a prolonged duration within a limited oral cavity,the tremor of dentist's hand is inevitable.As a result,wielding the drilling tool and inserting the dental implants safely in accurate position and orientation is highly challenging even for experienced dentists.Therefore,we introduce a customized manipulator that is designed ergonomically by taking in to account the dental chair specifications and anthropomorphic data such that it can be readily mounted onto the existing dental chair.The manipulator can be used to drill holes for dental inserts and position them with improved accuracy and safety.Further-more,a thorough multi-body motion analysis of the manipulator was carried out by creating a virtual prototype of the manipulator and simulating its controlled movements in various scenarios.The overall design was prepared and validated in simulation using Solid works,MATLAB and Simulink through Model Based Design(MBD)approach.The motion simulation results indicate that the manipulator could be built as a prototype readily.展开更多
This paper covers an experimental study on vocational students' participation in the class under task-based approach and traditional grammar-translation teaching method.As vocational colleges in China have develop...This paper covers an experimental study on vocational students' participation in the class under task-based approach and traditional grammar-translation teaching method.As vocational colleges in China have developed rapidly,teachers are still exploring and experimenting with different teaching approaches in order to find the suitable one(s).Using the theory of task-based approach,the grammartranslation method,the author conducts an experiment by recording.The following key issue has been addressed and some conclusive results have been made.The paper intends to find an answer to the following question:Under which teaching approach can students participate in the class more actively? Based on the above research work,the following result has been reached:Task-based approach can promote students' mastering of vocabulary and grammar,and students participate in the class more actively.The author would like to share her experiences with others in pedagogical studies of teaching vocational college students English.展开更多
A teaching experiment was conducted to investigate the feasibility and effectiveness of applying of Task-based approach(TBA) to business oral English teaching in higher vocational college.Instruments are tests and que...A teaching experiment was conducted to investigate the feasibility and effectiveness of applying of Task-based approach(TBA) to business oral English teaching in higher vocational college.Instruments are tests and questionnaire for the experimental participants.Based on the data analysis,it can be concluded that TBA proves to be more effective especially compared with PPP approach.展开更多
The traditional teaching approach is teacher-oriented,giving priority to grammar and lexical usage and neglecting the development of students’linguistic ability.The task-based approach is based on tasks and its promi...The traditional teaching approach is teacher-oriented,giving priority to grammar and lexical usage and neglecting the development of students’linguistic ability.The task-based approach is based on tasks and its prominent feature is"learning by doing and learning by using".By accomplishing tasks in target language,students can obtain linguistic knowledge and improve linguistic ability.This thesis is based on task-based approach,referring to English compulsory textbooks in senior middle school,exploring the application of task-based approach in intensive reading classes and providing case studies.展开更多
With the rapid development of economy and society,more and more people pay attention to English teaching.Vocabulary,the basic unit of language,is regarded as the center of language teaching by many linguists and educa...With the rapid development of economy and society,more and more people pay attention to English teaching.Vocabulary,the basic unit of language,is regarded as the center of language teaching by many linguists and educators.For Chinese students,vocabulary learning is also the most difficult and important problem in language learning.Unlike that in English-speaking countries,there is an absence of a foreign language environment for Chinese students,and most of their vocabulary is derived from classroom learning.Thus it is necessary to find an effective method to deal with vocabulary teaching.It analyzes college English vocabulary teaching,as college students have formed the corresponding language skills with more suitability.For a long time,students develop the habit of memorizing words repeatedly,consuming a lot of time,but the result is not satisfactory.Faced with this phenomenon,this paper analyzes the problems existing in College English vocabulary teaching and explores the reasons of the problems.Then it analyzes the application of task-based approach in college English vocabulary teaching.展开更多
The previous studies show that the major problems faced by the students in writing can be classified into two categories, that is, they don't know"what to write"and"how to write". The researche...The previous studies show that the major problems faced by the students in writing can be classified into two categories, that is, they don't know"what to write"and"how to write". The researchers found that the specific problems existing in their writings are identified as poor content, incomplete generic structure and misuse of cohesive devices. Therefore, on the basis of the previous studies, this study attempts to use Martin's genre theory to resolve the existed problems of the Professional College English major's students in writing and enhance students' discourse writing ability. Meanwhile, this study tries to answer the following questions:(1) Compared with the traditional writing teaching methods, whether the genre-based writing method has a significant effect to improve students' writing skills;(2) Whether the genre-based writing method is possible to increase students' interest in writing. The experimental result and the questionnaire show that genre-based approach in ESL writing teaching really can improve students' writing achievement and enhance students' interest in English writing.展开更多
A novel Lyapunov-based three-axis attitude intelligent control approach via allocation scheme is considered in the proposed research to deal with kinematics and dynamics regarding the unmanned aerial vehicle systems.T...A novel Lyapunov-based three-axis attitude intelligent control approach via allocation scheme is considered in the proposed research to deal with kinematics and dynamics regarding the unmanned aerial vehicle systems.There is a consensus among experts of this field that the new outcomes in the present complicated systems modeling and control are highly appreciated with respect to state-of-the-art.The control scheme presented here is organized in line with a new integration of the linear-nonlinear control approaches,as long as the angular velocities in the three axes of the system are accurately dealt with in the inner closed loop control.And the corresponding rotation angles are dealt with in the outer closed loop control.It should be noted that the linear control in the present outer loop is first designed through proportional based linear quadratic regulator(PD based LQR) approach under optimum coefficients,while the nonlinear control in the corresponding inner loop is then realized through Lyapunov-based approach in the presence of uncertainties and disturbances.In order to complete the inner closed loop control,there is a pulse-width pulse-frequency(PWPF) modulator to be able to handle on-off thrusters.Furthermore,the number of these on-off thrusters may be increased with respect to the investigated control efforts to provide the overall accurate performance of the system,where the control allocation scheme is realized in the proposed strategy.It may be shown that the dynamics and kinematics of the unmanned aerial vehicle systems have to be investigated through the quaternion matrix and its corresponding vector to avoid presenting singularity of the results.At the end,the investigated outcomes are presented in comparison with a number of potential benchmarks to verify the approach performance.展开更多
We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifte...We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.展开更多
To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-lev...To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-level data set of Beijing and employs a distance-based approach, which considers space as continuous. Unlike previous studies, we set two sets of references for service and manufacturing industries respectively to adapt to the investigation in the intra-urban area. Comparing among eight types of industries and different firm sizes, we find that: 1) producer service, high-tech industries and labor-intensive manufacturing industries are more likely to cluster, whereas personal service and capital-intensive industries tend to be randomly dispersed in Beijing; 2) the spillover of the co-location of firms is more important to knowledge-intensive industries and has more significant impact on their allocation than business-oriented services in the intra-urban area; 3) the spatial agglomeration of service industries are driven by larger establishments, whereas manufacturing industries are mixed.展开更多
Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil...Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil texture, soil salinity varies with short-term time. Thus, how to choose powerful environmental predictors is especially important for soil salinity. This paper presents a similarity-based prediction approach to map soil salinity and detects powerful environmental predictors for the Huanghe(Yellow) River Delta area in China. The similarity-based approach predicts the soil salinities of unsampled locations based on the environmental similarity between unsampled and sampled locations. A dataset of 92 points with salt data at depth of 30–40 cm was divided into two subsets for prediction and validation. Topographical parameters, soil textures, distances to irrigation channels and to the coastline, land surface temperature from Moderate Resolution Imaging Spectroradiometer(MODIS), Normalized Difference Vegetation Indices(NDVIs) and land surface reflectance data from Landsat Thematic Mapper(TM) imagery were generated. The similarity-based prediction approach was applied on several combinations of different environmental factors. Based on three evaluation indices including the correlation coefficient(CC) between observed and predicted values, the mean absolute error and the root mean squared error we found that elevation, distance to irrigation channels, soil texture, night land surface temperature, NDVI, and land surface reflectance Band 5 are the optimal combination for mapping soil salinity at the 30–40 cm depth in the study area(with a CC value of 0.69 and a root mean squared error value of 0.38). Our results indicated that the similarity-based prediction approach could be a vital alternative to other methods for mapping soil salinity, especially for area with limited observation data and could be used to monitor soil salinity distributions in the future.展开更多
A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that th...A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that the new insights may be taken into account as decision points to outperform the available materials. It is to note that the traditional control approaches may generally be upgraded, as long as a number of modifications are made with respect to state-of-the-art, in order to propose high-precision outcomes. Regarding the investigated issues, the robust sliding mode finite-time control approach is first designed to handle three-axis angular rates in the inner control loop, which consists of the pulse width pulse frequency modulations in line with the control allocation scheme and the system dynamics. The main subject to employ these modulations that is realizing in association with the control allocation scheme is to be able to handle a class of overactuated systems, in particular. The proportional derivative based linear quadratic regulator approach is then designed to handle three-axis rotational angles in the outer control loop, which consists of the system kinematics that is correspondingly concentrated to deal with the quaternion based model. The utilization of the linear and its nonlinear terms, simultaneously, are taken into real consideration as the research motivation, while the performance results are of the significance as the improved version in comparison with the recent investigated outcomes. Subsequently, there is a stability analysis to verify and guarantee the closed loop system performance in coping with the whole of nominal referenced commands. At the end, the effectiveness of the approach considered here is highlighted in line with a number of potential recent benchmarks.展开更多
In order to command a foreign language, it requires a balanced development in listening, speaking, reading and writing,which are four essential skills of language competence. Listening is not only a vital approach to ...In order to command a foreign language, it requires a balanced development in listening, speaking, reading and writing,which are four essential skills of language competence. Listening is not only a vital approach to acquire language, but also an important way to communicate with others in our daily life. The Task-based Approach(TBA) focuses on the specific task, which is the learning motivation. The process of finishing the task is the process of learning. The teaching result is judged by the task performed or not. This research discusses the application of TBA in English Listening Teaching at Middle Schools in order to improve the students listening ability. In the first part, the author introduces the background and significance of the research. In the second part, it states the definition of listening comprehension, the characteristics of listening process, three models of listening processing. In the third part, it introduces the definition of Task, characteristics of task, and the principles of designing a task. Finally, it introduces the Task-based Approach. In the fourth part, discusses the current situation of English teaching at middle school,and the elaboration on the task-based model of English listening teaching. All in all, the research is to make the audience to understand the application of Task-based Approach in English listening teaching at middle schools so as to improve the students' English listening ability.展开更多
Task-based teaching approach(TBTA) is widely accepted and plays a more important role in foreign language teach ing.This paper is aimed at analyzing specific task design and the application of task-based teaching appr...Task-based teaching approach(TBTA) is widely accepted and plays a more important role in foreign language teach ing.This paper is aimed at analyzing specific task design and the application of task-based teaching approach to business oral Eng lish teaching.It briefly introduces what the task-based teaching approach is and Willis'model for TBTA.Based on this model,it probes deeply into the teaching tasks design and teaching procedures.By applying the task-based teaching approach in business oral English teaching,teachers can assign students various tasks in the class to not only arose students'interest in English but also develop their communicative competence of business English.展开更多
文摘The awareness of applying genre in teaching and learning language has been aroused recently, and the choices of genres are connected closely with teachers' teaching goals and the needs of students. This paper which holds certain pedagogic purpose, analyzes genre-based teaching approach via an analysis on an English text book named Changes (level 1), aiming to help EFL teachers cultivate their genre awareness.
文摘During recent years,some notions about tasks have been considered as the major part of analysis in different teaching approaches and teachers are being more interested in the use of taskbased approach both in foreign and in second language teaching.The main goal of this article is to introduce and discuss some major principles of task-based language teaching and indicates how teachers can apply them in their curriculum.
文摘There are several teaching approaches being used to instruct the reading and writing teaching, such as the product approach, the process approach and the genre approach. In a long period, the product approach and the process approach dominate the field of writing teaching. With the development of genre and genre-analysis theory, we begin to realize that genre-based approach is effective in improving students ’ reading comprehension and writing. Based on the analysis of the theory and on the present situations of college English teaching and personal teaching experience, the genre-based teaching approach is introduced to the writing and reading comprehension teaching.
文摘Task-based language teaching approach(TBLTA), which lays stress on "learning by doing", gained increasing popularity in English teaching in recent years. The design of phonetic teaching calls for more emphasis from English educators since it is one of the basic rounds of English teaching. This paper made a trial on the utilization of TBLTA in the English phonetic teaching context and designed a TBLTA model for English phonetic teaching based on discussions about model and merits of TBLTA.
文摘Insufficient vocabulary has become a barrier to reading comprehension and translation in the process of ME (medical English) study to the third-year students at medical universities or colleges. The current study was designed to investigate corpus-based teaching ap-proach to enlarging students'vocabulary in the course of higher learning of ML (medical literature). The study was carried out from 2006.9 to 2008.9 among third-year medical students in our college. Students were encouraged to augment their vocabulary by active practice,intensive learning,and comprehensive learning respectively through discovering study by using self-made ME corpuses (90,000 words). In doing so,their vocabulary was enlarged by actively using the essential vocabulary,attaching more attention to the difficult technical vocabulary,and getting familiar with medical terms,which eliminated their language barrier,improved their integrated language proficiency,and developed their sense of achievement.
文摘This paper presents a Model-Based Design(MBD)approach for the design and control of a customized manipulator intended for drilling and position-ing of dental implants accurately with minimal human intervention.While performing an intra-oral surgery for a prolonged duration within a limited oral cavity,the tremor of dentist's hand is inevitable.As a result,wielding the drilling tool and inserting the dental implants safely in accurate position and orientation is highly challenging even for experienced dentists.Therefore,we introduce a customized manipulator that is designed ergonomically by taking in to account the dental chair specifications and anthropomorphic data such that it can be readily mounted onto the existing dental chair.The manipulator can be used to drill holes for dental inserts and position them with improved accuracy and safety.Further-more,a thorough multi-body motion analysis of the manipulator was carried out by creating a virtual prototype of the manipulator and simulating its controlled movements in various scenarios.The overall design was prepared and validated in simulation using Solid works,MATLAB and Simulink through Model Based Design(MBD)approach.The motion simulation results indicate that the manipulator could be built as a prototype readily.
文摘This paper covers an experimental study on vocational students' participation in the class under task-based approach and traditional grammar-translation teaching method.As vocational colleges in China have developed rapidly,teachers are still exploring and experimenting with different teaching approaches in order to find the suitable one(s).Using the theory of task-based approach,the grammartranslation method,the author conducts an experiment by recording.The following key issue has been addressed and some conclusive results have been made.The paper intends to find an answer to the following question:Under which teaching approach can students participate in the class more actively? Based on the above research work,the following result has been reached:Task-based approach can promote students' mastering of vocabulary and grammar,and students participate in the class more actively.The author would like to share her experiences with others in pedagogical studies of teaching vocational college students English.
文摘A teaching experiment was conducted to investigate the feasibility and effectiveness of applying of Task-based approach(TBA) to business oral English teaching in higher vocational college.Instruments are tests and questionnaire for the experimental participants.Based on the data analysis,it can be concluded that TBA proves to be more effective especially compared with PPP approach.
文摘The traditional teaching approach is teacher-oriented,giving priority to grammar and lexical usage and neglecting the development of students’linguistic ability.The task-based approach is based on tasks and its prominent feature is"learning by doing and learning by using".By accomplishing tasks in target language,students can obtain linguistic knowledge and improve linguistic ability.This thesis is based on task-based approach,referring to English compulsory textbooks in senior middle school,exploring the application of task-based approach in intensive reading classes and providing case studies.
文摘With the rapid development of economy and society,more and more people pay attention to English teaching.Vocabulary,the basic unit of language,is regarded as the center of language teaching by many linguists and educators.For Chinese students,vocabulary learning is also the most difficult and important problem in language learning.Unlike that in English-speaking countries,there is an absence of a foreign language environment for Chinese students,and most of their vocabulary is derived from classroom learning.Thus it is necessary to find an effective method to deal with vocabulary teaching.It analyzes college English vocabulary teaching,as college students have formed the corresponding language skills with more suitability.For a long time,students develop the habit of memorizing words repeatedly,consuming a lot of time,but the result is not satisfactory.Faced with this phenomenon,this paper analyzes the problems existing in College English vocabulary teaching and explores the reasons of the problems.Then it analyzes the application of task-based approach in college English vocabulary teaching.
文摘The previous studies show that the major problems faced by the students in writing can be classified into two categories, that is, they don't know"what to write"and"how to write". The researchers found that the specific problems existing in their writings are identified as poor content, incomplete generic structure and misuse of cohesive devices. Therefore, on the basis of the previous studies, this study attempts to use Martin's genre theory to resolve the existed problems of the Professional College English major's students in writing and enhance students' discourse writing ability. Meanwhile, this study tries to answer the following questions:(1) Compared with the traditional writing teaching methods, whether the genre-based writing method has a significant effect to improve students' writing skills;(2) Whether the genre-based writing method is possible to increase students' interest in writing. The experimental result and the questionnaire show that genre-based approach in ESL writing teaching really can improve students' writing achievement and enhance students' interest in English writing.
基金the Islamic Azad University (IAU),South Tehran Branch,Tehran,Iran in support of the present research
文摘A novel Lyapunov-based three-axis attitude intelligent control approach via allocation scheme is considered in the proposed research to deal with kinematics and dynamics regarding the unmanned aerial vehicle systems.There is a consensus among experts of this field that the new outcomes in the present complicated systems modeling and control are highly appreciated with respect to state-of-the-art.The control scheme presented here is organized in line with a new integration of the linear-nonlinear control approaches,as long as the angular velocities in the three axes of the system are accurately dealt with in the inner closed loop control.And the corresponding rotation angles are dealt with in the outer closed loop control.It should be noted that the linear control in the present outer loop is first designed through proportional based linear quadratic regulator(PD based LQR) approach under optimum coefficients,while the nonlinear control in the corresponding inner loop is then realized through Lyapunov-based approach in the presence of uncertainties and disturbances.In order to complete the inner closed loop control,there is a pulse-width pulse-frequency(PWPF) modulator to be able to handle on-off thrusters.Furthermore,the number of these on-off thrusters may be increased with respect to the investigated control efforts to provide the overall accurate performance of the system,where the control allocation scheme is realized in the proposed strategy.It may be shown that the dynamics and kinematics of the unmanned aerial vehicle systems have to be investigated through the quaternion matrix and its corresponding vector to avoid presenting singularity of the results.At the end,the investigated outcomes are presented in comparison with a number of potential benchmarks to verify the approach performance.
基金Supported by the National Natural Science Foundation of China under Grant No F050306
文摘We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.
基金State Key Program of National Natural Science of China(No.41230632)National Natural Science Foundation of China(No.41301123,41201169)
文摘To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-level data set of Beijing and employs a distance-based approach, which considers space as continuous. Unlike previous studies, we set two sets of references for service and manufacturing industries respectively to adapt to the investigation in the intra-urban area. Comparing among eight types of industries and different firm sizes, we find that: 1) producer service, high-tech industries and labor-intensive manufacturing industries are more likely to cluster, whereas personal service and capital-intensive industries tend to be randomly dispersed in Beijing; 2) the spillover of the co-location of firms is more important to knowledge-intensive industries and has more significant impact on their allocation than business-oriented services in the intra-urban area; 3) the spatial agglomeration of service industries are driven by larger establishments, whereas manufacturing industries are mixed.
基金Under the auspices of Special Fund for Ocean Public Welfare Profession Scientific Research(No.201105020)National Natural Science Foundation of China(No.41471178,41023010,41431177)National Key Technology Innovation Project for Water Pollution Control and Remediation(No.2013ZX07103006)
文摘Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil texture, soil salinity varies with short-term time. Thus, how to choose powerful environmental predictors is especially important for soil salinity. This paper presents a similarity-based prediction approach to map soil salinity and detects powerful environmental predictors for the Huanghe(Yellow) River Delta area in China. The similarity-based approach predicts the soil salinities of unsampled locations based on the environmental similarity between unsampled and sampled locations. A dataset of 92 points with salt data at depth of 30–40 cm was divided into two subsets for prediction and validation. Topographical parameters, soil textures, distances to irrigation channels and to the coastline, land surface temperature from Moderate Resolution Imaging Spectroradiometer(MODIS), Normalized Difference Vegetation Indices(NDVIs) and land surface reflectance data from Landsat Thematic Mapper(TM) imagery were generated. The similarity-based prediction approach was applied on several combinations of different environmental factors. Based on three evaluation indices including the correlation coefficient(CC) between observed and predicted values, the mean absolute error and the root mean squared error we found that elevation, distance to irrigation channels, soil texture, night land surface temperature, NDVI, and land surface reflectance Band 5 are the optimal combination for mapping soil salinity at the 30–40 cm depth in the study area(with a CC value of 0.69 and a root mean squared error value of 0.38). Our results indicated that the similarity-based prediction approach could be a vital alternative to other methods for mapping soil salinity, especially for area with limited observation data and could be used to monitor soil salinity distributions in the future.
文摘A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that the new insights may be taken into account as decision points to outperform the available materials. It is to note that the traditional control approaches may generally be upgraded, as long as a number of modifications are made with respect to state-of-the-art, in order to propose high-precision outcomes. Regarding the investigated issues, the robust sliding mode finite-time control approach is first designed to handle three-axis angular rates in the inner control loop, which consists of the pulse width pulse frequency modulations in line with the control allocation scheme and the system dynamics. The main subject to employ these modulations that is realizing in association with the control allocation scheme is to be able to handle a class of overactuated systems, in particular. The proportional derivative based linear quadratic regulator approach is then designed to handle three-axis rotational angles in the outer control loop, which consists of the system kinematics that is correspondingly concentrated to deal with the quaternion based model. The utilization of the linear and its nonlinear terms, simultaneously, are taken into real consideration as the research motivation, while the performance results are of the significance as the improved version in comparison with the recent investigated outcomes. Subsequently, there is a stability analysis to verify and guarantee the closed loop system performance in coping with the whole of nominal referenced commands. At the end, the effectiveness of the approach considered here is highlighted in line with a number of potential recent benchmarks.
文摘In order to command a foreign language, it requires a balanced development in listening, speaking, reading and writing,which are four essential skills of language competence. Listening is not only a vital approach to acquire language, but also an important way to communicate with others in our daily life. The Task-based Approach(TBA) focuses on the specific task, which is the learning motivation. The process of finishing the task is the process of learning. The teaching result is judged by the task performed or not. This research discusses the application of TBA in English Listening Teaching at Middle Schools in order to improve the students listening ability. In the first part, the author introduces the background and significance of the research. In the second part, it states the definition of listening comprehension, the characteristics of listening process, three models of listening processing. In the third part, it introduces the definition of Task, characteristics of task, and the principles of designing a task. Finally, it introduces the Task-based Approach. In the fourth part, discusses the current situation of English teaching at middle school,and the elaboration on the task-based model of English listening teaching. All in all, the research is to make the audience to understand the application of Task-based Approach in English listening teaching at middle schools so as to improve the students' English listening ability.
文摘Task-based teaching approach(TBTA) is widely accepted and plays a more important role in foreign language teach ing.This paper is aimed at analyzing specific task design and the application of task-based teaching approach to business oral Eng lish teaching.It briefly introduces what the task-based teaching approach is and Willis'model for TBTA.Based on this model,it probes deeply into the teaching tasks design and teaching procedures.By applying the task-based teaching approach in business oral English teaching,teachers can assign students various tasks in the class to not only arose students'interest in English but also develop their communicative competence of business English.