Based on the students' capability of assessing peers' essays, this paper attempts to analyze the effectiveness of peer feed-back in EFL writing. Significant improvements can be made in writing proficiency, esp...Based on the students' capability of assessing peers' essays, this paper attempts to analyze the effectiveness of peer feed-back in EFL writing. Significant improvements can be made in writing proficiency, especially for the students who review others' essays. The reviewers may not only improve their peer's papers but also improve general writing skills and learn to self-evaluatetheir own writing.展开更多
Since the result of effect comparison is important for teacher's decision making,roles teacher feedback and peer review play respectively and collaboratively in tertiary-level EFL writing context should be address...Since the result of effect comparison is important for teacher's decision making,roles teacher feedback and peer review play respectively and collaboratively in tertiary-level EFL writing context should be addressed via quantitative study as this paper proposed.Quantitative data should be collected from students'first drafts,second drafts and written comments from teachers and peers.Gains for overall scores between the first and second drafts and correlation between suggestions and gains should be examined.展开更多
Satisfactory simulation of negative shortwave（SW） radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes...Satisfactory simulation of negative shortwave（SW） radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes in the atmospheric and/or oceanic model, but the coupling process in coupled models has not received much attention. To investigate the coupling effect on SW feedback, two versions of an AGCM and their corresponding coupled models are analyzed. Results indicate that the effects of the coupling process in the two versions lead to weakening and enhancement of the negative feedback in the earlier and new versions, respectively, mainly due to their different changes in cloud fraction feedback and dynamical feedback. Further examination of the nonlinearity of the feedback reveals that the opposite coupling effects in the two versions originate from their different responses to El Nio and to La Nia.展开更多
We consider the impulsive effect on the exponential synchronization of neural networks with leakage delay under the sampled-data feedback control. We use an appropriate Lyapunov-Krasovskii functional combined with the...We consider the impulsive effect on the exponential synchronization of neural networks with leakage delay under the sampled-data feedback control. We use an appropriate Lyapunov-Krasovskii functional combined with the input delay approach and some inequality techniques to derive sufficient conditions that ensure the exponential synchronization of the delayed neural network. The conditions are formulated in terms of the leakage delay, the sampling period, and the exponential convergence rate. Numerical examples are given to demonstrate the usefulness and the effectiveness of the results.展开更多
Vector analysis technique and ecological sequential comparison methods were adopted to study tree growth response to the micronutrients, B, Mo, Cu, Zn, Fe, and Mn, in soils derived from various parent materials in the...Vector analysis technique and ecological sequential comparison methods were adopted to study tree growth response to the micronutrients, B, Mo, Cu, Zn, Fe, and Mn, in soils derived from various parent materials in the forest area of Taihu Lake region in southeast China. The results showed that the dry weight of individual current-year needle of Chinese fir (Cunninghamia lanceolata) grown on the soi1 derived from granite parent rock was increased by 8% and 13% in comparison with that grown on the soils derived from sandstone and ash-tuff parent rock, respectively. And such dry weight of loblolly pine (Pinus taeda) grown on the soil derived from sandstone parent rock was increased by 21% in comparison with that on the soil derived from ash-tuff parent rock. One of the reasons for those results was that micronutrients content in the soil derived from ash-tuff parent rock were not sufficient to meet the requirement of the growth of Chinese fir and loblolly pine, i.e., micronutrients in soil were deficient and/or induced deficient. The amounts of Cu, Zn, Fe, and Mn uptake by Chinese fir and loblolly pine were in agreement with the contents of available micronutrients in soil respectively, except for B and Mo. Meanwhile, there might exist an "antagonism" between the uptake of B versus Mo by trees, although more studies are needed to confirm it. Regression analysis indicated that amount of a soil available micronutrient was correlated to the type of parent material and its total amount in the forest floor, except for B. The F test identified that the correlation of each equation reached the significant level to different extents, respectively. The t test confirmed that amount of available forms was mainly depended on the type of parent material for Mo, Cu, Zn and Mn but on the forest floor for Fe. There was a feedback effect of forest stand on the amount of soil available micronutrients. The ability of accumulating available micronutrients in soil was better by the sawtooth oak (Quercus acutissima) stand than by the Chinese fir stand (except for B). The ability of accumulating available Zn, Fe, Mn and Mo in soil was better by the Chinese fir stand than by the loblolly pine stand, while as for available B and Cu, by the latter was better than by the former. When discussing the effect of forest stand on the amount of soil available micronutrients, not only the amount of micronutrient in the forest floor and the parent materials but also the amount of micronutrient taken up by current-year needles have to be considered.展开更多
In China, it is widely believed that teacher feedback plays a crucial role in EFL writing course, exerting a great impact on the improvement of Chinese EFL students＇ writing abilities so that teachers have been requi...In China, it is widely believed that teacher feedback plays a crucial role in EFL writing course, exerting a great impact on the improvement of Chinese EFL students＇ writing abilities so that teachers have been required to deliver feedback on students＇ writings. Teachers, consequently, spare no pains to give feedback, expecting their students would make progress in their writing, but it seems that things go contrary to their wishes. Although there are various complicated factors contributing to the situation, one of the important factors lies in the teachers, a number of whom do not grasp a systematic and effective mechanism of delivering feedback on EFL student writing. Much importance has been attached to Chinese EFL student writing, however, rare attention has been paid to conducting research on concrete ways of delivering feedback on Chinese EFL student writing in China. Therefore, this paper serves to fill the gap, mainly devoting itself to exploring concrete methods of delivering teacher feedback on EFL student writing.展开更多
Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB b...Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB bandwidth of the TS-DFB laser is increased to 17.6 GHz and that chirp parameter can be reduced to 2.24.Compared to the absence of a detuned loading effect,there is a 4.6 GHz increase and a 2.45 reduction,respectively.After transmitting a 10 Gb/s non-return-to-zero(NRZ)signal through a 5-km fiber,the modulation eye diagram still achieves a large opening.Eight-channel laser arrays with precise wavelength spacing are fabricated.Each TS-DFB laser in the array has side mode suppression ratios(SMSR)>49.093 dB and the maximum wavelength residual<0.316 nm.展开更多
文摘Based on the students' capability of assessing peers' essays, this paper attempts to analyze the effectiveness of peer feed-back in EFL writing. Significant improvements can be made in writing proficiency, especially for the students who review others' essays. The reviewers may not only improve their peer's papers but also improve general writing skills and learn to self-evaluatetheir own writing.
文摘Since the result of effect comparison is important for teacher's decision making,roles teacher feedback and peer review play respectively and collaboratively in tertiary-level EFL writing context should be addressed via quantitative study as this paper proposed.Quantitative data should be collected from students'first drafts,second drafts and written comments from teachers and peers.Gains for overall scores between the first and second drafts and correlation between suggestions and gains should be examined.
基金supported by the National Basic Research Program of China[973 Program,grant number 2015CB954102]the National Natural Sciences Foundation of China[grant number41205079]the China Postdoctoral Science Foundation[grant number 2016M591234]
文摘Satisfactory simulation of negative shortwave（SW） radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes in the atmospheric and/or oceanic model, but the coupling process in coupled models has not received much attention. To investigate the coupling effect on SW feedback, two versions of an AGCM and their corresponding coupled models are analyzed. Results indicate that the effects of the coupling process in the two versions lead to weakening and enhancement of the negative feedback in the earlier and new versions, respectively, mainly due to their different changes in cloud fraction feedback and dynamical feedback. Further examination of the nonlinearity of the feedback reveals that the opposite coupling effects in the two versions originate from their different responses to El Nio and to La Nia.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(Grant No.2013R1A1A2A10005201)the UAE University(Grant No.NRF Project UAEU-NRF-7-20886)
文摘We consider the impulsive effect on the exponential synchronization of neural networks with leakage delay under the sampled-data feedback control. We use an appropriate Lyapunov-Krasovskii functional combined with the input delay approach and some inequality techniques to derive sufficient conditions that ensure the exponential synchronization of the delayed neural network. The conditions are formulated in terms of the leakage delay, the sampling period, and the exponential convergence rate. Numerical examples are given to demonstrate the usefulness and the effectiveness of the results.
基金Project supported by the National Natural Science Foundation of China (No. 39370563)by the NationalKey Basic Research Suppor
文摘Vector analysis technique and ecological sequential comparison methods were adopted to study tree growth response to the micronutrients, B, Mo, Cu, Zn, Fe, and Mn, in soils derived from various parent materials in the forest area of Taihu Lake region in southeast China. The results showed that the dry weight of individual current-year needle of Chinese fir (Cunninghamia lanceolata) grown on the soi1 derived from granite parent rock was increased by 8% and 13% in comparison with that grown on the soils derived from sandstone and ash-tuff parent rock, respectively. And such dry weight of loblolly pine (Pinus taeda) grown on the soil derived from sandstone parent rock was increased by 21% in comparison with that on the soil derived from ash-tuff parent rock. One of the reasons for those results was that micronutrients content in the soil derived from ash-tuff parent rock were not sufficient to meet the requirement of the growth of Chinese fir and loblolly pine, i.e., micronutrients in soil were deficient and/or induced deficient. The amounts of Cu, Zn, Fe, and Mn uptake by Chinese fir and loblolly pine were in agreement with the contents of available micronutrients in soil respectively, except for B and Mo. Meanwhile, there might exist an "antagonism" between the uptake of B versus Mo by trees, although more studies are needed to confirm it. Regression analysis indicated that amount of a soil available micronutrient was correlated to the type of parent material and its total amount in the forest floor, except for B. The F test identified that the correlation of each equation reached the significant level to different extents, respectively. The t test confirmed that amount of available forms was mainly depended on the type of parent material for Mo, Cu, Zn and Mn but on the forest floor for Fe. There was a feedback effect of forest stand on the amount of soil available micronutrients. The ability of accumulating available micronutrients in soil was better by the sawtooth oak (Quercus acutissima) stand than by the Chinese fir stand (except for B). The ability of accumulating available Zn, Fe, Mn and Mo in soil was better by the Chinese fir stand than by the loblolly pine stand, while as for available B and Cu, by the latter was better than by the former. When discussing the effect of forest stand on the amount of soil available micronutrients, not only the amount of micronutrient in the forest floor and the parent materials but also the amount of micronutrient taken up by current-year needles have to be considered.
文摘In China, it is widely believed that teacher feedback plays a crucial role in EFL writing course, exerting a great impact on the improvement of Chinese EFL students＇ writing abilities so that teachers have been required to deliver feedback on students＇ writings. Teachers, consequently, spare no pains to give feedback, expecting their students would make progress in their writing, but it seems that things go contrary to their wishes. Although there are various complicated factors contributing to the situation, one of the important factors lies in the teachers, a number of whom do not grasp a systematic and effective mechanism of delivering feedback on EFL student writing. Much importance has been attached to Chinese EFL student writing, however, rare attention has been paid to conducting research on concrete ways of delivering feedback on Chinese EFL student writing in China. Therefore, this paper serves to fill the gap, mainly devoting itself to exploring concrete methods of delivering teacher feedback on EFL student writing.
文摘Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB bandwidth of the TS-DFB laser is increased to 17.6 GHz and that chirp parameter can be reduced to 2.24.Compared to the absence of a detuned loading effect,there is a 4.6 GHz increase and a 2.45 reduction,respectively.After transmitting a 10 Gb/s non-return-to-zero(NRZ)signal through a 5-km fiber,the modulation eye diagram still achieves a large opening.Eight-channel laser arrays with precise wavelength spacing are fabricated.Each TS-DFB laser in the array has side mode suppression ratios(SMSR)>49.093 dB and the maximum wavelength residual<0.316 nm.
