The agricultural land resources of China are relatively limited because of its large population.Therefore,balancing the land use for industrialization,urbanization,and food security is a big challenge.In recent years,...The agricultural land resources of China are relatively limited because of its large population.Therefore,balancing the land use for industrialization,urbanization,and food security is a big challenge.In recent years,rural hollowing in China has resulted in numerous of abandoned rural houses,and the areas with abandoned houses need to be restored into agricultural land with effective land consolidation techniques.This study used the method of benefit-cost analysis and the data collected through field surveys conducted in Yucheng City in the northwest of Shandong Province in March 2009,to examine how hollow villages (HVs) to be created and how to solve the problem.The qualitative and quantitative analyses indicate following results.1) The situation of HVs is becoming increasingly severe under rapid industrialization and urbanization in Yucheng City.2) Poor infrastructure in rural areas and incomplete urbanization are the main factors that have led to the rural hollowing in many major rural regions of China.3) In order to resolve the problem caused by HVs and increase agricultural land,reconstructing rural communities in the countryside is necessary.4) A new mechanism in the provision of compensation funds by developed regions to the villages in less-developed regions must be established.展开更多
A novel adaptive digital image watermark algorithm is proposed. Fuzzy c-means clustering （FCM） is used to classify the original image blocks into two classes based on several characteristic parameters of human visua...A novel adaptive digital image watermark algorithm is proposed. Fuzzy c-means clustering （FCM） is used to classify the original image blocks into two classes based on several characteristic parameters of human visual system （HVS）. One is suited for embedding a digital watermark, the other is not. So the appropriate blocks in an image are selected to embed the watermark. The wetermark is embedded in the middle-frequency part of the host image in conjunction with HVS and discrete cosine transform （DCT）. The maximal watermark strength is fixed according to the frequency masking. In the same time, for the good performance, the watermark is modulated into a fractal modulation array. The simulation results show that we can remarkably extract the hiding watermark and the algorithm can achieve good robustness with common signal distortion or geometric distortion and the quality of the watermarked image is guaranteed.展开更多
Intra refresh is an efficient and simple technique for suppressing temporal error propagation in video transmission over error-prone networks. However, most existing intra refresh algorithms do not make good use of th...Intra refresh is an efficient and simple technique for suppressing temporal error propagation in video transmission over error-prone networks. However, most existing intra refresh algorithms do not make good use of the visual perceptual mechanism of the Human Visual System （HVS）. This paper presents an intra refresh algorithm based on an attention model and a loss impact model. Intra refresh rates are allowed to vary for different image regions according to the HVS characteristic and the channel conditions to protect the most important macro-blocks against packet loss. A joint source-channel rate-distortion model was de- veloped taking into account the HVS characteristic to achieve an optimal end-to-end distortion for a better subjective quality. Tests demonstrate that, for the same bit rate and packet loss rate, this method provides a much better subjective feeling than existing intra refresh methods.展开更多
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-EW-304)National Natural Science Foundation of China (No.40635029,40871257)
文摘The agricultural land resources of China are relatively limited because of its large population.Therefore,balancing the land use for industrialization,urbanization,and food security is a big challenge.In recent years,rural hollowing in China has resulted in numerous of abandoned rural houses,and the areas with abandoned houses need to be restored into agricultural land with effective land consolidation techniques.This study used the method of benefit-cost analysis and the data collected through field surveys conducted in Yucheng City in the northwest of Shandong Province in March 2009,to examine how hollow villages (HVs) to be created and how to solve the problem.The qualitative and quantitative analyses indicate following results.1) The situation of HVs is becoming increasingly severe under rapid industrialization and urbanization in Yucheng City.2) Poor infrastructure in rural areas and incomplete urbanization are the main factors that have led to the rural hollowing in many major rural regions of China.3) In order to resolve the problem caused by HVs and increase agricultural land,reconstructing rural communities in the countryside is necessary.4) A new mechanism in the provision of compensation funds by developed regions to the villages in less-developed regions must be established.
基金Supported by the National Natural Science Foundation ofChina (10571127) the Doctoral Foundation of the Ministry of Educationof China (20040610004)
文摘A novel adaptive digital image watermark algorithm is proposed. Fuzzy c-means clustering （FCM） is used to classify the original image blocks into two classes based on several characteristic parameters of human visual system （HVS）. One is suited for embedding a digital watermark, the other is not. So the appropriate blocks in an image are selected to embed the watermark. The wetermark is embedded in the middle-frequency part of the host image in conjunction with HVS and discrete cosine transform （DCT）. The maximal watermark strength is fixed according to the frequency masking. In the same time, for the good performance, the watermark is modulated into a fractal modulation array. The simulation results show that we can remarkably extract the hiding watermark and the algorithm can achieve good robustness with common signal distortion or geometric distortion and the quality of the watermarked image is guaranteed.
基金Supported by the National Natural Science Foundation of China(No. 60572081)
文摘Intra refresh is an efficient and simple technique for suppressing temporal error propagation in video transmission over error-prone networks. However, most existing intra refresh algorithms do not make good use of the visual perceptual mechanism of the Human Visual System （HVS）. This paper presents an intra refresh algorithm based on an attention model and a loss impact model. Intra refresh rates are allowed to vary for different image regions according to the HVS characteristic and the channel conditions to protect the most important macro-blocks against packet loss. A joint source-channel rate-distortion model was de- veloped taking into account the HVS characteristic to achieve an optimal end-to-end distortion for a better subjective quality. Tests demonstrate that, for the same bit rate and packet loss rate, this method provides a much better subjective feeling than existing intra refresh methods.
