This study examines the reliability and validity of AI-generated scoring for continuation writing tasks.By comparing GPT-4 with eight experienced human raters across 21 student responses,it evaluates AI’s consistency...This study examines the reliability and validity of AI-generated scoring for continuation writing tasks.By comparing GPT-4 with eight experienced human raters across 21 student responses,it evaluates AI’s consistency,severity,and alignment with human scoring criteria.Results show that AI exhibits high self-consistency and adapts effectively to different scoring roles(e.g.,teacher vs.highstakes rater).However,AI scores were more lenient than human raters and demonstrated divergent evaluation focuses—prioritizing narrative coherence and emotional depth,while teachers emphasized linguistic accuracy and richness of detail.The findings suggest AI’s potential as a supplementary assessment tool,offering rapid,holistic feedback,but highlight the need for further calibration to align with educational standards.Implications include exploring hybrid evaluation models that leverage the strengths of both AI and human raters to achieve more equitable,efficient,and pedagogically meaningful writing assessments.展开更多
The iterative continuation task(ICT)requires English as a foreign language(EFL)learners to read a segment and write a continuation that aligns with the preceding segment of an English novel with successive turns,offer...The iterative continuation task(ICT)requires English as a foreign language(EFL)learners to read a segment and write a continuation that aligns with the preceding segment of an English novel with successive turns,offering exposure to diverse grammatical structures and opportunities for contextualized usage.Given the importance of integrating technology into second language(L2)writing and the critical role that grammar plays in L2 writing development,automated written corrective feedback provided by Grammarly has gained significant attention.This study investigates the impact of Grammarly on grammar learning strategies,grammar grit,and grammar competence among EFL college students engaged in ICT.This study employed a mixed-methods sequential exploratory design;56 participants were divided into an experimental group(n=28),receiving Grammarly feedback for ICT,and a control group(n=28),completing ICT without Grammarly feedback.Quantitative results revealed that both groups showed improvements in L2 grammar learning strategies,grit and competence.For the experimental group,significant differences were observed across all variables of L2 grammar learning strategies,grit,and competence between pre-and post-tests.For the control group,significant differences were only observed in the affective dimension of grammar learning strategies,Consistency of Interest(COI)of grammar grit,and grammar competence.However,the control group presented a significantly higher improvement in grammar competence.Qualitative analysis showed both positive and negative perceptions of Grammarly.The pedagogical implications of integrating Grammarly and ICT for L2 grammar development are discussed.展开更多
This study investigated the effects of xu-argument-based continuation writing on learners’processing of source texts.Seventy-five participants were randomly assigned to three conditions:(1)continuation writing,(2)sum...This study investigated the effects of xu-argument-based continuation writing on learners’processing of source texts.Seventy-five participants were randomly assigned to three conditions:(1)continuation writing,(2)summary writing,or(3)reading comprehension.Eye-tracking data were collected during reading,measuring early(first fixation duration,first pass duration)and late(go-past time,total fixation duration)eye movements.During writing,source-text rereading was tracked via fixation counts and durations.Results showed that task type did not affect initial lexical access,as first fixation duration showed no group differences.However,both production groups exhibited significantly longer first pass durations than the reading comprehension group.Late measures revealed a gradient pattern:the continuation writing group spent significantly longer gopast time and total fixation duration than the summary writing group,which exceeded the reading comprehension group.This indicates that continuation tasks promoted deeper cognitive engagement during reading.During writing,the continuation writing group spent more time rereading the source text with higher fixation counts than the summary writing group.These findings suggest that continuation writing triggers more intensive reader-text interaction during pre-writing and enhances comprehension-production coupling through sustained attention to input during writing.This study sheds light on the cognitive mechanisms underlying the theoretical and pedagogical value of xu-argument.展开更多
This study integrates explicit input enhancement into comparative continuation writing,defined as a task in which learners produce a continuation by comparing their own expression with an input text,aligning with its ...This study integrates explicit input enhancement into comparative continuation writing,defined as a task in which learners produce a continuation by comparing their own expression with an input text,aligning with its discourse structure and linguistic features,while developing their own ideas.It aims to examine whether English as a Foreign Language(EFL)learners in China exhibit differences in discourse competence and writing performance when completing comparative continuation writing combined with different input enhancement techniques,and whether the alignment effect occurs at the discourse level.Sixty first-year Chinese senior middle school students were divided into four groups:three groups engaged in comparative continuation writing with varying input enhancement,achieved by combining different techniques,while a control group performed a designated-topic writing task.The results revealed that three comparative continuation writing groups outperformed the designated-topic writing group in discourse competence,particularly in the use of temporal connectives.However,differences and some inconsistencies were observed among the comparative continuation writing groups across individual indices.The study highlights effective ways to incorporate comparative continuation writing into English instruction and demonstrates how explicit input enhancement can complement the task,simultaneously activating the alignment effect proposed by the xu-argument and enhancing discourse competence in writing.展开更多
This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants...This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs.展开更多
This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a con...This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a continuation group, a MAFW group, and a control group, each with30 learners. A pretest and a posttest were used to gauge L2 writing development. Results showedthat the continuation task outperformed the MAFW task not only in enhancing the overall qualityof L2 writing, but also in promoting the quality of three components of L2 writing, namely, content,organization, and language. The finding has important implications for L2 writing teaching andlearning.展开更多
Rhetorical devices are a kind of language expression often seen in articles.With the development of the new era,the requirements for listening,speaking,reading and writing in today's English education are graduall...Rhetorical devices are a kind of language expression often seen in articles.With the development of the new era,the requirements for listening,speaking,reading and writing in today's English education are gradually increasing,and the requirements for writing are also getting higher and higher.In the English curriculum standards for senior high schools(2017 edition),the Ministry of Education also further improved the requirements of high school students'listening,speaking,reading and writing skills.In high school English textbooks,each unit of the article often contains a variety of rhetorical devices,but high school students cannot skillfully use rhetorical devices in the continuation writing.Therefore,it is necessary to explore the use of rhetorical devices in post reading continuation.This paper analyzes the application of rhetorical devices in the continuation of high school reading.Using the output oriented teaching method in teaching to help students understand and apply.The purpose is to let high school students understand the embodiment of rhetorical devices in English articles;Be able to master and skillfully use rhetorical devices in the continuation writing.This paper decides to explore and study rhetorical sentence patterns to help students increase their ability to write English and improve their appreciation of the beauty of the English language.展开更多
The analytic continuation serves as a crucial bridge between quantum Monte Carlo calculations in imaginary-time formalism,specifically the Green's functions,and physical measurements(the spectral functions)in real...The analytic continuation serves as a crucial bridge between quantum Monte Carlo calculations in imaginary-time formalism,specifically the Green's functions,and physical measurements(the spectral functions)in real time.Various approaches have been developed to enhance the accuracy of analytic continuation,including the Padéapproximation,the maximum entropy method,and stochastic analytic continuation.In this study,we employ different deep learning techniques to investigate the analytic continuation for the quantum impurity model.A significant challenge in this context is that the sharp Abrikosov-Suhl resonance peak may be either underestimated or overestimated.We fit both the imaginary-time Green's function and the spectral function using Chebyshev polynomials in logarithmic coordinates.We utilize Full-Connected Networks(FCN),Convolutional Neural Networks(CNNs),and Residual Networks(ResNet)to address this issue.Our findings indicate that introducing noise during the training phase significantly improves the accuracy of the learning process.The typical absolute error achieved is less than 10-4.These investigations pave the way for machine learning to optimize the analytic continuation problem in many-body systems,thereby reducing the need for prior expertise in physics.展开更多
Continuation method solving forward kinematics problem of parallel robot was discussed. And through a coefficient-parameter continuation method the efficiency and feasibility of continuation method were improved. Usin...Continuation method solving forward kinematics problem of parallel robot was discussed. And through a coefficient-parameter continuation method the efficiency and feasibility of continuation method were improved. Using this method all forward solutions of a new parallel robot model which was put forward lately by Robot Open Laboratory of Science Institute of China were obtained. Therefore it provided the basis of mechanism analysis and real-time control for new model.展开更多
Stability is the key to inverse Q-filtering. In this paper we present a stable approach to inverse Q-filtering, based on the theory of wavefield downward continuation. It is implemented in a layered manner, assuming a...Stability is the key to inverse Q-filtering. In this paper we present a stable approach to inverse Q-filtering, based on the theory of wavefield downward continuation. It is implemented in a layered manner, assuming a layered-earth Q model. For each individual constant Q layer, the seismic wavefield recorded at the surface is first extrapolated down to the top of the current layer and a constant Q inverse filter is then applied to the current layer. When extrapolating within the overburden, a stable wavefield continuation algorithm in combination with a stabilization factor is applied. This avoids accumulating inverse Q-filter errors within the overburden. Within the current constant Q layer, we use Gabor spectral analysis on the signals to pick time-variant gain-constrained frequencies and then deduce the corresponding gain-constrained amplitudes to stabilize the inverse Q-filtering algorithm. The algorithm is tested and verified application to field data.展开更多
Based on the preferential continuation method proposed by Pawlowski （1995）, we propose a method and procedure for gravity anomaly separation with the preferential upward continuation operator in the case that the va...Based on the preferential continuation method proposed by Pawlowski （1995）, we propose a method and procedure for gravity anomaly separation with the preferential upward continuation operator in the case that the various sources are uncorrelated with one another and the continuation height is enough large. We also present a method for estimating optimum upward-continuation height, based on analyzing the characteristics of the preferential upward continuation operators of a synthesized gravity anomaly varying with different continuation heights. The method is tested on the raw Bouguer gravity data over an iron deposit. The result shows that the method separates the data into regional anomaly and residual anomaly efficiently and clearly.展开更多
In order to eliminate the effect of ocean bottom topography on seismic wave field,we transformed curved（x,z）coordinate system grids into rectangular（ξ,η）coordinate system grids and derived a 2-D scalar acoustic ...In order to eliminate the effect of ocean bottom topography on seismic wave field,we transformed curved（x,z）coordinate system grids into rectangular（ξ,η）coordinate system grids and derived a 2-D scalar acoustic wave equation in theξ,ηdomain.The seismic wave field collected at the sea surface was downward continued to the ocean bottom by the inverse finite difference method with the water velocity and then was reversely continued to the ocean surface by the finite difference method using the layer velocity from just below the ocean bottom in the（ξ,η）domain.Simulation calculations and practical application show that this method can not only remove the reflection travel time distortion but also correct the dynamic parameter changes caused by the ocean bottom topography.The inverted velocity after wave field continuation is much more accurate than before continuation and the image section was greatly improved compared to the original wave field.展开更多
This paper presents the flight dynamical behavior of the thrust vectoring aircraft with extended bifurcation and continuation methods. In contrast to the standard bifurcation and continuation methods, the extended met...This paper presents the flight dynamical behavior of the thrust vectoring aircraft with extended bifurcation and continuation methods. In contrast to the standard bifurcation and continuation methods, the extended methods are capable of calculating the continuation curves of the equilibrium points for the particular type of trimming flight. Therefore, these methods can not only give the performance measures of aircraft, but also determine the stability of trimming points. In this paper, the methods are used to verify the effectiveness of the thrust vectoring control law, to define the flight envelope boundary, to analyze the stability and controllability of trimming flight, and to predict the departures of the instable flight. The result shows that the extended methods provide more flight dynamic information and are useful in preliminary design of the thrust vectoring aircraft.展开更多
In this article, the unique continuation and persistence properties of solutions of the 2-component Degasperis-Procesi equations are discussed. It is shown that strong solutions of the 2-component Degasperis-Procesi e...In this article, the unique continuation and persistence properties of solutions of the 2-component Degasperis-Procesi equations are discussed. It is shown that strong solutions of the 2-component Degasperis-Procesi equations, initially decaying exponentially together with its spacial derivative, must be identically equal to zero if they also decay exponentially at a later time.展开更多
This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construct...This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity.展开更多
Based on the xu-argument, this study investigated the use of translation continuation tasks in commercial translation instruction. Forty-four second-year Business English majors at a Chinese university participated in...Based on the xu-argument, this study investigated the use of translation continuation tasks in commercial translation instruction. Forty-four second-year Business English majors at a Chinese university participated in the study. They were divided into equal-sized control and experimental groups. Members of the experimental group were asked to read Chinese-English parallel texts from a user manual, while those of the control group were asked to read the Chinese text only.Subsequently, both groups were required to translate the continued Chinese text into English. The results indicated the following: 1) the experimental group’s translated text was of significantly higher quality than that of the control group;and 2) the experimental group’s translations were well-aligned with the original text in their use of terminology, sentence structure, and stylistic features. The study concludes by suggesting that translation continuation tasks can improve commercial translation instruction and hence should be further applied in practice.展开更多
For the first time,the analytical continuation in the coupling constant method has been combined with the relativistic mean field theory to study the unbound states in spherical nuclei.The 1d_(3/2) neutron state in ^(...For the first time,the analytical continuation in the coupling constant method has been combined with the relativistic mean field theory to study the unbound states in spherical nuclei.The 1d_(3/2) neutron state in ^(16)O and the 2d_(5/2) and 1g_(9/2) neutron states in ^(48)Ca are taken as examples.The calculated energies and widths are compared with available data.展开更多
The present study employed a quantitative and network approach to detect alignment effects in second language(L2) continuation tasks designed on the xu-argument(Wang, 2016). The materials used in this study were 6 sub...The present study employed a quantitative and network approach to detect alignment effects in second language(L2) continuation tasks designed on the xu-argument(Wang, 2016). The materials used in this study were 6 sub-corpora consisting of two selected input stories and two groups of L2 written production based on two continuation tasks. During continuation, the participants were required to continue in English a story with its ending removed, with one group reading and continuing the Chinese version and the other group the English version, and then switching their roles in the two tasks. Results show that the alignment effect differs across the two versions of continuation. Specifically, compared with the Chinese-version continuation, L2 learners produced more use of unigrams and bigrams similar to the input story in terms of lexical items, frequency and ranking correlations in the English-version task;on the other hand, the English-version continuation can facilitate generating linguistic networks that are much closer to the native English networks. Moreover, this research corroborates that written production in L2 continuation tasks can be influenced by input content.展开更多
When topography and low velocity zone differences vary greatly, conventional vertical static time shifts will cause wavefield distortion and influence wave equation seismic imaging for seismic data acquired on a compl...When topography and low velocity zone differences vary greatly, conventional vertical static time shifts will cause wavefield distortion and influence wave equation seismic imaging for seismic data acquired on a complex near surface. In this paper, we propose an approach to datum correction that combines a joint tomography inversion with wavefield continuation to solve the static problem for seismic data on rugged acquisition topography. First, the near surface model is obtained by refracted wave tomography inversion. Second, the wavefield of sources and receivers are continued downward and upward to accomplish datum correction starting from a flat surface and locating the datum above topography. Based on the reciprocal theorem, Huygens＇ and Fresnel principles, the location of sources and receivers, and regarding the recorded data on the surface as a secondary emission, the sources and receivers are upward-continued to the datum above topography respectively. Thus, the datum correction using joint tomography inversion and wavefield continuation with the condition of a complex near surface is accomplished.展开更多
文摘This study examines the reliability and validity of AI-generated scoring for continuation writing tasks.By comparing GPT-4 with eight experienced human raters across 21 student responses,it evaluates AI’s consistency,severity,and alignment with human scoring criteria.Results show that AI exhibits high self-consistency and adapts effectively to different scoring roles(e.g.,teacher vs.highstakes rater).However,AI scores were more lenient than human raters and demonstrated divergent evaluation focuses—prioritizing narrative coherence and emotional depth,while teachers emphasized linguistic accuracy and richness of detail.The findings suggest AI’s potential as a supplementary assessment tool,offering rapid,holistic feedback,but highlight the need for further calibration to align with educational standards.Implications include exploring hybrid evaluation models that leverage the strengths of both AI and human raters to achieve more equitable,efficient,and pedagogically meaningful writing assessments.
文摘The iterative continuation task(ICT)requires English as a foreign language(EFL)learners to read a segment and write a continuation that aligns with the preceding segment of an English novel with successive turns,offering exposure to diverse grammatical structures and opportunities for contextualized usage.Given the importance of integrating technology into second language(L2)writing and the critical role that grammar plays in L2 writing development,automated written corrective feedback provided by Grammarly has gained significant attention.This study investigates the impact of Grammarly on grammar learning strategies,grammar grit,and grammar competence among EFL college students engaged in ICT.This study employed a mixed-methods sequential exploratory design;56 participants were divided into an experimental group(n=28),receiving Grammarly feedback for ICT,and a control group(n=28),completing ICT without Grammarly feedback.Quantitative results revealed that both groups showed improvements in L2 grammar learning strategies,grit and competence.For the experimental group,significant differences were observed across all variables of L2 grammar learning strategies,grit,and competence between pre-and post-tests.For the control group,significant differences were only observed in the affective dimension of grammar learning strategies,Consistency of Interest(COI)of grammar grit,and grammar competence.However,the control group presented a significantly higher improvement in grammar competence.Qualitative analysis showed both positive and negative perceptions of Grammarly.The pedagogical implications of integrating Grammarly and ICT for L2 grammar development are discussed.
文摘This study investigated the effects of xu-argument-based continuation writing on learners’processing of source texts.Seventy-five participants were randomly assigned to three conditions:(1)continuation writing,(2)summary writing,or(3)reading comprehension.Eye-tracking data were collected during reading,measuring early(first fixation duration,first pass duration)and late(go-past time,total fixation duration)eye movements.During writing,source-text rereading was tracked via fixation counts and durations.Results showed that task type did not affect initial lexical access,as first fixation duration showed no group differences.However,both production groups exhibited significantly longer first pass durations than the reading comprehension group.Late measures revealed a gradient pattern:the continuation writing group spent significantly longer gopast time and total fixation duration than the summary writing group,which exceeded the reading comprehension group.This indicates that continuation tasks promoted deeper cognitive engagement during reading.During writing,the continuation writing group spent more time rereading the source text with higher fixation counts than the summary writing group.These findings suggest that continuation writing triggers more intensive reader-text interaction during pre-writing and enhances comprehension-production coupling through sustained attention to input during writing.This study sheds light on the cognitive mechanisms underlying the theoretical and pedagogical value of xu-argument.
文摘This study integrates explicit input enhancement into comparative continuation writing,defined as a task in which learners produce a continuation by comparing their own expression with an input text,aligning with its discourse structure and linguistic features,while developing their own ideas.It aims to examine whether English as a Foreign Language(EFL)learners in China exhibit differences in discourse competence and writing performance when completing comparative continuation writing combined with different input enhancement techniques,and whether the alignment effect occurs at the discourse level.Sixty first-year Chinese senior middle school students were divided into four groups:three groups engaged in comparative continuation writing with varying input enhancement,achieved by combining different techniques,while a control group performed a designated-topic writing task.The results revealed that three comparative continuation writing groups outperformed the designated-topic writing group in discourse competence,particularly in the use of temporal connectives.However,differences and some inconsistencies were observed among the comparative continuation writing groups across individual indices.The study highlights effective ways to incorporate comparative continuation writing into English instruction and demonstrates how explicit input enhancement can complement the task,simultaneously activating the alignment effect proposed by the xu-argument and enhancing discourse competence in writing.
文摘This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs.
文摘This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a continuation group, a MAFW group, and a control group, each with30 learners. A pretest and a posttest were used to gauge L2 writing development. Results showedthat the continuation task outperformed the MAFW task not only in enhancing the overall qualityof L2 writing, but also in promoting the quality of three components of L2 writing, namely, content,organization, and language. The finding has important implications for L2 writing teaching andlearning.
文摘Rhetorical devices are a kind of language expression often seen in articles.With the development of the new era,the requirements for listening,speaking,reading and writing in today's English education are gradually increasing,and the requirements for writing are also getting higher and higher.In the English curriculum standards for senior high schools(2017 edition),the Ministry of Education also further improved the requirements of high school students'listening,speaking,reading and writing skills.In high school English textbooks,each unit of the article often contains a variety of rhetorical devices,but high school students cannot skillfully use rhetorical devices in the continuation writing.Therefore,it is necessary to explore the use of rhetorical devices in post reading continuation.This paper analyzes the application of rhetorical devices in the continuation of high school reading.Using the output oriented teaching method in teaching to help students understand and apply.The purpose is to let high school students understand the embodiment of rhetorical devices in English articles;Be able to master and skillfully use rhetorical devices in the continuation writing.This paper decides to explore and study rhetorical sentence patterns to help students increase their ability to write English and improve their appreciation of the beauty of the English language.
基金Sponsored by National Natural Science Foundation of China(Grant No.12174101)Fundamental Research Funds for the Central Universities(Grant No.2022MS051).
文摘The analytic continuation serves as a crucial bridge between quantum Monte Carlo calculations in imaginary-time formalism,specifically the Green's functions,and physical measurements(the spectral functions)in real time.Various approaches have been developed to enhance the accuracy of analytic continuation,including the Padéapproximation,the maximum entropy method,and stochastic analytic continuation.In this study,we employ different deep learning techniques to investigate the analytic continuation for the quantum impurity model.A significant challenge in this context is that the sharp Abrikosov-Suhl resonance peak may be either underestimated or overestimated.We fit both the imaginary-time Green's function and the spectral function using Chebyshev polynomials in logarithmic coordinates.We utilize Full-Connected Networks(FCN),Convolutional Neural Networks(CNNs),and Residual Networks(ResNet)to address this issue.Our findings indicate that introducing noise during the training phase significantly improves the accuracy of the learning process.The typical absolute error achieved is less than 10-4.These investigations pave the way for machine learning to optimize the analytic continuation problem in many-body systems,thereby reducing the need for prior expertise in physics.
文摘Continuation method solving forward kinematics problem of parallel robot was discussed. And through a coefficient-parameter continuation method the efficiency and feasibility of continuation method were improved. Using this method all forward solutions of a new parallel robot model which was put forward lately by Robot Open Laboratory of Science Institute of China were obtained. Therefore it provided the basis of mechanism analysis and real-time control for new model.
基金This research is sponsored by the National"973"Project(No.2007CB209603)the"863"Project(No.2006AA06Z108)
文摘Stability is the key to inverse Q-filtering. In this paper we present a stable approach to inverse Q-filtering, based on the theory of wavefield downward continuation. It is implemented in a layered manner, assuming a layered-earth Q model. For each individual constant Q layer, the seismic wavefield recorded at the surface is first extrapolated down to the top of the current layer and a constant Q inverse filter is then applied to the current layer. When extrapolating within the overburden, a stable wavefield continuation algorithm in combination with a stabilization factor is applied. This avoids accumulating inverse Q-filter errors within the overburden. Within the current constant Q layer, we use Gabor spectral analysis on the signals to pick time-variant gain-constrained frequencies and then deduce the corresponding gain-constrained amplitudes to stabilize the inverse Q-filtering algorithm. The algorithm is tested and verified application to field data.
基金supported jointly by projects of the 863 Program (Grant Nos.2006AA06Z111,2006AA06A201-3,and 20060109A1002-0201-03)
文摘Based on the preferential continuation method proposed by Pawlowski （1995）, we propose a method and procedure for gravity anomaly separation with the preferential upward continuation operator in the case that the various sources are uncorrelated with one another and the continuation height is enough large. We also present a method for estimating optimum upward-continuation height, based on analyzing the characteristics of the preferential upward continuation operators of a synthesized gravity anomaly varying with different continuation heights. The method is tested on the raw Bouguer gravity data over an iron deposit. The result shows that the method separates the data into regional anomaly and residual anomaly efficiently and clearly.
基金sponsored by the National 973 Program of China(Grant No.2009CB219505)International Science&Technology Cooperation Program of China(Grant No.2010DFA21630)
文摘In order to eliminate the effect of ocean bottom topography on seismic wave field,we transformed curved（x,z）coordinate system grids into rectangular（ξ,η）coordinate system grids and derived a 2-D scalar acoustic wave equation in theξ,ηdomain.The seismic wave field collected at the sea surface was downward continued to the ocean bottom by the inverse finite difference method with the water velocity and then was reversely continued to the ocean surface by the finite difference method using the layer velocity from just below the ocean bottom in the（ξ,η）domain.Simulation calculations and practical application show that this method can not only remove the reflection travel time distortion but also correct the dynamic parameter changes caused by the ocean bottom topography.The inverted velocity after wave field continuation is much more accurate than before continuation and the image section was greatly improved compared to the original wave field.
文摘This paper presents the flight dynamical behavior of the thrust vectoring aircraft with extended bifurcation and continuation methods. In contrast to the standard bifurcation and continuation methods, the extended methods are capable of calculating the continuation curves of the equilibrium points for the particular type of trimming flight. Therefore, these methods can not only give the performance measures of aircraft, but also determine the stability of trimming points. In this paper, the methods are used to verify the effectiveness of the thrust vectoring control law, to define the flight envelope boundary, to analyze the stability and controllability of trimming flight, and to predict the departures of the instable flight. The result shows that the extended methods provide more flight dynamic information and are useful in preliminary design of the thrust vectoring aircraft.
基金supported by NNSFC(11001219,10925104)the Scientific Research Program Funded by Shaanxi Provincial Education Department(2010JK860)
文摘In this article, the unique continuation and persistence properties of solutions of the 2-component Degasperis-Procesi equations are discussed. It is shown that strong solutions of the 2-component Degasperis-Procesi equations, initially decaying exponentially together with its spacial derivative, must be identically equal to zero if they also decay exponentially at a later time.
文摘This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity.
文摘Based on the xu-argument, this study investigated the use of translation continuation tasks in commercial translation instruction. Forty-four second-year Business English majors at a Chinese university participated in the study. They were divided into equal-sized control and experimental groups. Members of the experimental group were asked to read Chinese-English parallel texts from a user manual, while those of the control group were asked to read the Chinese text only.Subsequently, both groups were required to translate the continued Chinese text into English. The results indicated the following: 1) the experimental group’s translated text was of significantly higher quality than that of the control group;and 2) the experimental group’s translations were well-aligned with the original text in their use of terminology, sentence structure, and stylistic features. The study concludes by suggesting that translation continuation tasks can improve commercial translation instruction and hence should be further applied in practice.
基金Supported partly by the Major State Basic Research Development Program under Contract Number G2000077407the National Natural Science Foundation of China under Grant Nos.19847002 and 19935030.
文摘For the first time,the analytical continuation in the coupling constant method has been combined with the relativistic mean field theory to study the unbound states in spherical nuclei.The 1d_(3/2) neutron state in ^(16)O and the 2d_(5/2) and 1g_(9/2) neutron states in ^(48)Ca are taken as examples.The calculated energies and widths are compared with available data.
文摘The present study employed a quantitative and network approach to detect alignment effects in second language(L2) continuation tasks designed on the xu-argument(Wang, 2016). The materials used in this study were 6 sub-corpora consisting of two selected input stories and two groups of L2 written production based on two continuation tasks. During continuation, the participants were required to continue in English a story with its ending removed, with one group reading and continuing the Chinese version and the other group the English version, and then switching their roles in the two tasks. Results show that the alignment effect differs across the two versions of continuation. Specifically, compared with the Chinese-version continuation, L2 learners produced more use of unigrams and bigrams similar to the input story in terms of lexical items, frequency and ranking correlations in the English-version task;on the other hand, the English-version continuation can facilitate generating linguistic networks that are much closer to the native English networks. Moreover, this research corroborates that written production in L2 continuation tasks can be influenced by input content.
基金the National Development and Innovation Committee Program (2005) 2372the National High-tech R&D Program (863 Program) 2006AA06Z241 of ChinaYouth Innovation Fund of CNPC’ Prestack Imaging Integral Study for Complex near Surface.
文摘When topography and low velocity zone differences vary greatly, conventional vertical static time shifts will cause wavefield distortion and influence wave equation seismic imaging for seismic data acquired on a complex near surface. In this paper, we propose an approach to datum correction that combines a joint tomography inversion with wavefield continuation to solve the static problem for seismic data on rugged acquisition topography. First, the near surface model is obtained by refracted wave tomography inversion. Second, the wavefield of sources and receivers are continued downward and upward to accomplish datum correction starting from a flat surface and locating the datum above topography. Based on the reciprocal theorem, Huygens＇ and Fresnel principles, the location of sources and receivers, and regarding the recorded data on the surface as a secondary emission, the sources and receivers are upward-continued to the datum above topography respectively. Thus, the datum correction using joint tomography inversion and wavefield continuation with the condition of a complex near surface is accomplished.
