This paper explores the potential to use accurate but outdated channel estimates for adaptive modulation. The work is novel in that the research is conditioned on block by block adaptation. First,we define a new quant...This paper explores the potential to use accurate but outdated channel estimates for adaptive modulation. The work is novel in that the research is conditioned on block by block adaptation. First,we define a new quantity,the Tolerable Average Use Delay (TAUD),which can indicate the ability of an adaptation scheme to tolerate the delay of channel estimation results. We find that for the variable-power schemes,TAUD is a constant and dependent on the target Bit Error Rate (BER),average power and Doppler frequency; while for the constant-power schemes,it depends on the ad-aptation block length as well. At last,we investigate the relation between the delay tolerating per-formance and the spectral efficiency and give the system design criterion. The delay tolerating per-formance is improved at the price of lower data rate.展开更多
The Eastern Guangxi area locates in the southwestern part of the transition zone between Yangtze and Cathaysia blocks, which is an important region because the boundary between two blocks probablycrosses there. We det...The Eastern Guangxi area locates in the southwestern part of the transition zone between Yangtze and Cathaysia blocks, which is an important region because the boundary between two blocks probablycrosses there. We determined LA-ICPMS U-Pb ages for detrital zircons extracted from three sandstone samples in the Sinian-Cambrian strata in this region. The resulting ages are in the range of the Archeozoic and Neoproterozoic, with three notable concentrates at 991 Ma, 974 Ma, and 964 Ma, all of which are coeval to the Grenvillian magmatic activity. The new age distribution is similar to the data reported in the Precambrian strata of the adjacent southwestern Cathaysia Block, suggesting that most of our detrital zircons are likely derived from the Cathaysia Block. Combined with others＇ research, we are more inclined to accept the opinion that there was not an ocean basin between the two blocks during the Sinian-Cambrian period in Eastern Guangxi area if the timing of collision is the Early Neoproterzoic. But if the timing of collision is the Early Paleozoic, we conclude that Luzhai uplift（i.e., the uplift between Guilin-Yongfu faultand Lipu fault） beyond the west of Dayaoshan regoin might be one part of southwestern sedimentation boundary of Cathaysia Block and Yangtze Block. We also get a few of detrital zircons with ages of ~590 Ma which probably sourced from northeastern Gondwana and 13 detrital zircons with over 3 000 Ma U-Pb ages which record the early formation of the earth.展开更多
In this paper,we propose a shear high-order gradient(SHOG)operator by combining the shear operator and high-order gradient(HOG)operator.Compared with the HOG operator,the proposed SHOG operator can incorporate more di...In this paper,we propose a shear high-order gradient(SHOG)operator by combining the shear operator and high-order gradient(HOG)operator.Compared with the HOG operator,the proposed SHOG operator can incorporate more directionality and detect more abundant edge information.Based on the SHOG operator,we extend the total variation(TV)norm to shear high-order total variation(SHOTV),and then propose a SHOTV deblurring model.We also study some properties of the SHOG operator,and show that the SHOG matrices are Block Circulant with Circulant Blocks(BCCB)when the shear angle isπ/4.The proposed model is solved efficiently by the alternating direction method of multipliers(ADMM).Experimental results demonstrate that the proposed method outperforms some state-of-the-art non-blind deblurring methods in both objective and perceptual quality.展开更多
In this paper, we propose a novel shear gradient operator by combining the shear and gradient operators. The shear gradient operator performs well to capture diverse directional information in the image gradient domai...In this paper, we propose a novel shear gradient operator by combining the shear and gradient operators. The shear gradient operator performs well to capture diverse directional information in the image gradient domain. Based on the shear gradient operator, we extend the total variation(TV) norm to the shear total variation(STV) norm by adding two shear gradient terms. Subsequently, we introduce a shear total variation deblurring model. Experimental results are provided to validate the ability of the STV norm to capture the detailed information. Leveraging the Block Circulant with Circulant Blocks(BCCB) structure of the shear gradient matrices, the alternating direction method of multipliers(ADMM) algorithm can be used to solve the proposed model efficiently. Numerous experiments are presented to verify the performance of our algorithm for non-blind image deblurring.展开更多
Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear...Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel＇s face. In this context, intact as well as rock mass strength and deformation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method（FEM） is used for stability analysis purpose by parametrically varying rock joint persistence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.展开更多
Fast algorithms for reducing encoding complexity of fractal image coding have recently been an important research topic. Search of the best matched domain block is the most computation intensive part of the fractal en...Fast algorithms for reducing encoding complexity of fractal image coding have recently been an important research topic. Search of the best matched domain block is the most computation intensive part of the fractal encoding process. In this paper, a fast fractal approximation coding scheme implemented on a personal computer based on matching in range block's neighbours is presented.Experimental results show that the proposed algorithm is very simple in implementation, fast in encoding time and high in compression ratio while PSNR is almost the same as compared with Barnsley's fractal block coding .展开更多
In this paper,potential use of perfect but delayed channel estimates for variable-power discrete-rate adaptive modulation is explored.Research is concentrated on block by block adaptation.At first,a new quantity-TAUD(...In this paper,potential use of perfect but delayed channel estimates for variable-power discrete-rate adaptive modulation is explored.Research is concentrated on block by block adaptation.At first,a new quantity-TAUD(Tolerable Average Use Delay)is defined,it quantifies the performance of an adaptation scheme in tolerating the delay of channel estimates.Then,the research on TAUD shows that the delay tolerating performance declines with the increase in average power,the scheme working with more modulation modes can tolerate a longer delay,and such improvement will be more significant with the increase of average power.Finally,it shows that,as the delay tolerating performance determines the maximum block length,it has a great effect on the maximum spectral efficiency.The criterion for determining the block length appropriate for the target BER is described and a simple method of calculating the maximum block length is presented.展开更多
In this paper, we propose a product image retrieval method based on the object contour corners, image texture and color. The product image mainly highlights the object and its background is very simple. According to t...In this paper, we propose a product image retrieval method based on the object contour corners, image texture and color. The product image mainly highlights the object and its background is very simple. According to these characteristics, we represent the object using its contour, and detect the corners of contour to reduce the number of pixels. Every corner is described using its approximate curvature based on distance. In addition, the Block Difference of Inverse Probabilities (BDIP) and Block Variation of Local Correlation (BVLC) texture features and color moment are extracted from image's HIS color space. Finally, dynamic time warping method is used to match features with different length. In order to demonstrate the effect of the proposed method, we carry out experiments in Mi-crosoft product image database, and compare it with other feature descriptors. The retrieval precision and recall curves show that our method is feasible.展开更多
基金Supported by the National Natural Science Foundation of China (No.60496311).
文摘This paper explores the potential to use accurate but outdated channel estimates for adaptive modulation. The work is novel in that the research is conditioned on block by block adaptation. First,we define a new quantity,the Tolerable Average Use Delay (TAUD),which can indicate the ability of an adaptation scheme to tolerate the delay of channel estimation results. We find that for the variable-power schemes,TAUD is a constant and dependent on the target Bit Error Rate (BER),average power and Doppler frequency; while for the constant-power schemes,it depends on the ad-aptation block length as well. At last,we investigate the relation between the delay tolerating per-formance and the spectral efficiency and give the system design criterion. The delay tolerating per-formance is improved at the price of lower data rate.
基金jointly supported by the National Natural Science Foundation of China (No.41102131)the Fundamental Research Funds for the Central Universities of China (No.12lgpy22)+3 种基金Guangdong Natural Science Foundation (No.2015A030313193)China Geological Survey (No.1212011121064)Chinese Association for science and technology project (No.2014XSJLW01-02)China Scholarship Council
文摘The Eastern Guangxi area locates in the southwestern part of the transition zone between Yangtze and Cathaysia blocks, which is an important region because the boundary between two blocks probablycrosses there. We determined LA-ICPMS U-Pb ages for detrital zircons extracted from three sandstone samples in the Sinian-Cambrian strata in this region. The resulting ages are in the range of the Archeozoic and Neoproterozoic, with three notable concentrates at 991 Ma, 974 Ma, and 964 Ma, all of which are coeval to the Grenvillian magmatic activity. The new age distribution is similar to the data reported in the Precambrian strata of the adjacent southwestern Cathaysia Block, suggesting that most of our detrital zircons are likely derived from the Cathaysia Block. Combined with others＇ research, we are more inclined to accept the opinion that there was not an ocean basin between the two blocks during the Sinian-Cambrian period in Eastern Guangxi area if the timing of collision is the Early Neoproterzoic. But if the timing of collision is the Early Paleozoic, we conclude that Luzhai uplift（i.e., the uplift between Guilin-Yongfu faultand Lipu fault） beyond the west of Dayaoshan regoin might be one part of southwestern sedimentation boundary of Cathaysia Block and Yangtze Block. We also get a few of detrital zircons with ages of ~590 Ma which probably sourced from northeastern Gondwana and 13 detrital zircons with over 3 000 Ma U-Pb ages which record the early formation of the earth.
基金Supported by the National Natural Science Foundation of China(61701004)Outstanding Young Talents Support Program of Anhui Province(gxyq2021178)+1 种基金Open Fund of Key Laboratory of Anhui Higher Education Institutes(CS2021-07)Program of University Mathematics Teaching Research and Development Center(CMC20200301)。
文摘In this paper,we propose a shear high-order gradient(SHOG)operator by combining the shear operator and high-order gradient(HOG)operator.Compared with the HOG operator,the proposed SHOG operator can incorporate more directionality and detect more abundant edge information.Based on the SHOG operator,we extend the total variation(TV)norm to shear high-order total variation(SHOTV),and then propose a SHOTV deblurring model.We also study some properties of the SHOG operator,and show that the SHOG matrices are Block Circulant with Circulant Blocks(BCCB)when the shear angle isπ/4.The proposed model is solved efficiently by the alternating direction method of multipliers(ADMM).Experimental results demonstrate that the proposed method outperforms some state-of-the-art non-blind deblurring methods in both objective and perceptual quality.
基金Supported by Open Fund of Key Laboratory of Anhui Higher Education Institutes (CS2021-07)the National Natural Science Foundation of China (61701004)Outstanding Young Talents Support Program of Anhui Province (gxyq2021178)。
文摘In this paper, we propose a novel shear gradient operator by combining the shear and gradient operators. The shear gradient operator performs well to capture diverse directional information in the image gradient domain. Based on the shear gradient operator, we extend the total variation(TV) norm to the shear total variation(STV) norm by adding two shear gradient terms. Subsequently, we introduce a shear total variation deblurring model. Experimental results are provided to validate the ability of the STV norm to capture the detailed information. Leveraging the Block Circulant with Circulant Blocks(BCCB) structure of the shear gradient matrices, the alternating direction method of multipliers(ADMM) algorithm can be used to solve the proposed model efficiently. Numerous experiments are presented to verify the performance of our algorithm for non-blind image deblurring.
基金The financial support provided by the Hydro China Scientific Research Project (GW-KJ-2013-11)
文摘Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel＇s face. In this context, intact as well as rock mass strength and deformation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method（FEM） is used for stability analysis purpose by parametrically varying rock joint persistence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.
文摘Fast algorithms for reducing encoding complexity of fractal image coding have recently been an important research topic. Search of the best matched domain block is the most computation intensive part of the fractal encoding process. In this paper, a fast fractal approximation coding scheme implemented on a personal computer based on matching in range block's neighbours is presented.Experimental results show that the proposed algorithm is very simple in implementation, fast in encoding time and high in compression ratio while PSNR is almost the same as compared with Barnsley's fractal block coding .
基金supported by National Natural Science Foundation of China(No.61071087)Chun Lei 2009BWZ037 from SDUST,China
文摘In this paper,potential use of perfect but delayed channel estimates for variable-power discrete-rate adaptive modulation is explored.Research is concentrated on block by block adaptation.At first,a new quantity-TAUD(Tolerable Average Use Delay)is defined,it quantifies the performance of an adaptation scheme in tolerating the delay of channel estimates.Then,the research on TAUD shows that the delay tolerating performance declines with the increase in average power,the scheme working with more modulation modes can tolerate a longer delay,and such improvement will be more significant with the increase of average power.Finally,it shows that,as the delay tolerating performance determines the maximum block length,it has a great effect on the maximum spectral efficiency.The criterion for determining the block length appropriate for the target BER is described and a simple method of calculating the maximum block length is presented.
基金Supported by the Major Program of National Natural Science Foundation of China (No. 70890080 and No. 70890083)
文摘In this paper, we propose a product image retrieval method based on the object contour corners, image texture and color. The product image mainly highlights the object and its background is very simple. According to these characteristics, we represent the object using its contour, and detect the corners of contour to reduce the number of pixels. Every corner is described using its approximate curvature based on distance. In addition, the Block Difference of Inverse Probabilities (BDIP) and Block Variation of Local Correlation (BVLC) texture features and color moment are extracted from image's HIS color space. Finally, dynamic time warping method is used to match features with different length. In order to demonstrate the effect of the proposed method, we carry out experiments in Mi-crosoft product image database, and compare it with other feature descriptors. The retrieval precision and recall curves show that our method is feasible.
