This paper deals with the temperature correlation of gray scale of B-mode ultrasound image from heated tissue. In this study, many in-vitro fresh pig livers are heated in a temperature range from 28 ℃ to 45℃, from w...This paper deals with the temperature correlation of gray scale of B-mode ultrasound image from heated tissue. In this study, many in-vitro fresh pig livers are heated in a temperature range from 28 ℃ to 45℃, from which a series of B-mode ultrasonic images of livers were obtained. The gray-value is evaluated from the ultrasound images respectively. A correlation of the mean gray value of the selected regions (12×12 pixels) in B-mode ultrasonic images of liver and its temperature was pointed out. And the experiment results agreed the evaluation well. And it is possible to monitor the tissue temperature changing in hyperthermia using this correlation.展开更多
To decrease the computational complexity of adaptive inter-layer prediction and improve the encoding efficiency in sealable video coding, a mode decision algorithm is proposed by exploiting the part of used candidate ...To decrease the computational complexity of adaptive inter-layer prediction and improve the encoding efficiency in sealable video coding, a mode decision algorithm is proposed by exploiting the part of used candidate modes of the co-located reference macrobloeks for Hierarchical-B pictures. This scheme reduces the amount of the candidate modes to generate a dynamic list for the current encoding macroblock according to the statistical information derived from the co-located reference macroblocks in different temporal levels. The experimental results show that this fast algorithm reduces approximately 31% encoding time on average with the negligible loss of encoding performance.展开更多
广播式自动相关监视(ADS-B)报头检测方法的优劣直接决定着接收机的性能。为了解决脉冲匹配检测方法受脉冲能量影响较大的不足,提出了一种基带归一化的互相关报头检测方法。首先将基带信号根据动态门限进行归一化,然后将其与标准报头作...广播式自动相关监视(ADS-B)报头检测方法的优劣直接决定着接收机的性能。为了解决脉冲匹配检测方法受脉冲能量影响较大的不足,提出了一种基带归一化的互相关报头检测方法。首先将基带信号根据动态门限进行归一化,然后将其与标准报头作互相关,最后通过相关峰检测来判定信号的存在和到达时间。与主流基于脉冲位置和上升沿的检测方法相比,该方法隐含地利用了脉冲位置、上升沿、下降沿、脉冲宽度、非脉冲区等多个信息用于检测报头,且无需进行下行格式(DF)认证。仿真结果表明:该方法在信噪比大于2 d B时检测性能略优,在信噪比小于2 d B时检测性能与主流检测方法相差1 d B。在实际接收实验中,以该方法为基础的信号接收效果良好,在视距内可以形成稳定连续的航迹,证明了该方法的实用性。展开更多
基金The research was supported by National Nature Science Foundation (30470450) Education Committee Foundation( KP0608200201 ) Elitist Foundation( KW5800200351 ) from Beijing City,China.
文摘This paper deals with the temperature correlation of gray scale of B-mode ultrasound image from heated tissue. In this study, many in-vitro fresh pig livers are heated in a temperature range from 28 ℃ to 45℃, from which a series of B-mode ultrasonic images of livers were obtained. The gray-value is evaluated from the ultrasound images respectively. A correlation of the mean gray value of the selected regions (12×12 pixels) in B-mode ultrasonic images of liver and its temperature was pointed out. And the experiment results agreed the evaluation well. And it is possible to monitor the tissue temperature changing in hyperthermia using this correlation.
基金Sponsored by the Fundamental Research Funds for the Central Universities(Grant No. HEUCF11805)
文摘To decrease the computational complexity of adaptive inter-layer prediction and improve the encoding efficiency in sealable video coding, a mode decision algorithm is proposed by exploiting the part of used candidate modes of the co-located reference macrobloeks for Hierarchical-B pictures. This scheme reduces the amount of the candidate modes to generate a dynamic list for the current encoding macroblock according to the statistical information derived from the co-located reference macroblocks in different temporal levels. The experimental results show that this fast algorithm reduces approximately 31% encoding time on average with the negligible loss of encoding performance.
文摘广播式自动相关监视(ADS-B)报头检测方法的优劣直接决定着接收机的性能。为了解决脉冲匹配检测方法受脉冲能量影响较大的不足,提出了一种基带归一化的互相关报头检测方法。首先将基带信号根据动态门限进行归一化,然后将其与标准报头作互相关,最后通过相关峰检测来判定信号的存在和到达时间。与主流基于脉冲位置和上升沿的检测方法相比,该方法隐含地利用了脉冲位置、上升沿、下降沿、脉冲宽度、非脉冲区等多个信息用于检测报头,且无需进行下行格式(DF)认证。仿真结果表明:该方法在信噪比大于2 d B时检测性能略优,在信噪比小于2 d B时检测性能与主流检测方法相差1 d B。在实际接收实验中,以该方法为基础的信号接收效果良好,在视距内可以形成稳定连续的航迹,证明了该方法的实用性。
