A cognitive radio transmitted reference ultra-wideband（CR-TR-UWB） system is proposed to improve the performance of TR-UWB systems with narrowband interference（NBI） from primary users（PU）.The transmitter of the C...A cognitive radio transmitted reference ultra-wideband（CR-TR-UWB） system is proposed to improve the performance of TR-UWB systems with narrowband interference（NBI） from primary users（PU）.The transmitter of the CR-TR-UWB system detects the band of PU,and then sends prolate spheroidal wave functions（PSWF） pulses with the same limited band as PU＇s to reduce interference with PU.The receiver uses a notch filter before autocorrelation to eliminate NBI from PU.The simulation results show that the bit error rate（BER） performance of the CR-TR-UWB system is close to that of TR-UWB systems without NBI when the system is interfered by single or double NBIs with a signal to interference ratio（SIR） of 0 dB,and if the signal to noise ratio（SNR） is 10 dB and the SIR varies from-20 to 10 dB,BER performance varies no more than an order of magnitude.The system has excellent resistance to NBI,strong robustness BER performance at different SNRs,and smaller interference with the same frequency band PU.展开更多
[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlatio...[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation（AC） as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter（WNPBF） based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric（PN）,Electron-ion Interaction Potential（EIIP） and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods.展开更多
Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communicatio...Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communication network. It works by injecting a modulated carrier wave into the electric cables from one transceiver to another. But still, the noise level and impedance mismatch are still the main concern of this technology, particularly in the low voltage network in residential area. Power line has additive non-white noise and extremely harsh environment for communication. At the same time, there is signal attenuation along the power line caused by the impedance mismatch in the power line network. Even though these problems can be controlled using a band-pass filter and an impedance matching circuit respectively, but the impedances in the power line are time and location variant and it is rather difficult to design a circuit that allows maximum power transfer in the system all the time. Thus in this paper, a new adaptive impedance matching circuits is proposed for narrowband power line communication. This methodology is derived based on the RLC band-pass filter circuit. This concept is designed to achieve simpler configuration and higher matching resolution.展开更多
目的在高清非放大结肠镜下观察大肠息肉表面形态特点,与病理组织学诊断进行对照研究,评价息肉黏膜表面形态特点对大肠息肉病理类型的预判能力。方法对142例结直肠息肉患者330枚息肉样病变进行高清结肠镜检查并观察黏膜腺管开口形态,采...目的在高清非放大结肠镜下观察大肠息肉表面形态特点,与病理组织学诊断进行对照研究,评价息肉黏膜表面形态特点对大肠息肉病理类型的预判能力。方法对142例结直肠息肉患者330枚息肉样病变进行高清结肠镜检查并观察黏膜腺管开口形态,采用窄波带成像技术(narrow band imaging,NBI)观察黏膜表面血管形态(capillary pattern,CP),与息肉病理结果对照判定其敏感性、特异性及准确率。结果高清非放大结肠镜下联合黏膜腺管开口形态及黏膜表面血管形态判定息肉表面形态特点对鉴别肿瘤性与非肿瘤性病变的敏感性为88.2%,特异性为83.6%,阳性预测值为95.5%,阴性预测值为64.4%,准确度为87.3%,阳性相似比为5.4,阴性相似比为0.1。结论高清非放大结肠镜下贴近观察结合NBI显像观察息肉表面形态对于鉴别大肠息肉是否为肿瘤性有重要价值,与病理诊断有较好的符合率,有助于决定进一步治疗及随访方案。展开更多
基金The National Research and Development Program of China(863 Program)(No.2007AA12Z238)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No. 12KJD510008)
文摘A cognitive radio transmitted reference ultra-wideband（CR-TR-UWB） system is proposed to improve the performance of TR-UWB systems with narrowband interference（NBI） from primary users（PU）.The transmitter of the CR-TR-UWB system detects the band of PU,and then sends prolate spheroidal wave functions（PSWF） pulses with the same limited band as PU＇s to reduce interference with PU.The receiver uses a notch filter before autocorrelation to eliminate NBI from PU.The simulation results show that the bit error rate（BER） performance of the CR-TR-UWB system is close to that of TR-UWB systems without NBI when the system is interfered by single or double NBIs with a signal to interference ratio（SIR） of 0 dB,and if the signal to noise ratio（SNR） is 10 dB and the SIR varies from-20 to 10 dB,BER performance varies no more than an order of magnitude.The system has excellent resistance to NBI,strong robustness BER performance at different SNRs,and smaller interference with the same frequency band PU.
基金Supported by Ningxia Natural Science Foundation (NZ1024)the Scientific Research the Project of Ningxia Universities (201027)~~
文摘[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation（AC） as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter（WNPBF） based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric（PN）,Electron-ion Interaction Potential（EIIP） and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods.
文摘Power line communication technology is used in various applications, from high voltage network to the low voltage network, as it is the only wired communication technology that is comparable with wireless communication network. It works by injecting a modulated carrier wave into the electric cables from one transceiver to another. But still, the noise level and impedance mismatch are still the main concern of this technology, particularly in the low voltage network in residential area. Power line has additive non-white noise and extremely harsh environment for communication. At the same time, there is signal attenuation along the power line caused by the impedance mismatch in the power line network. Even though these problems can be controlled using a band-pass filter and an impedance matching circuit respectively, but the impedances in the power line are time and location variant and it is rather difficult to design a circuit that allows maximum power transfer in the system all the time. Thus in this paper, a new adaptive impedance matching circuits is proposed for narrowband power line communication. This methodology is derived based on the RLC band-pass filter circuit. This concept is designed to achieve simpler configuration and higher matching resolution.
文摘目的在高清非放大结肠镜下观察大肠息肉表面形态特点,与病理组织学诊断进行对照研究,评价息肉黏膜表面形态特点对大肠息肉病理类型的预判能力。方法对142例结直肠息肉患者330枚息肉样病变进行高清结肠镜检查并观察黏膜腺管开口形态,采用窄波带成像技术(narrow band imaging,NBI)观察黏膜表面血管形态(capillary pattern,CP),与息肉病理结果对照判定其敏感性、特异性及准确率。结果高清非放大结肠镜下联合黏膜腺管开口形态及黏膜表面血管形态判定息肉表面形态特点对鉴别肿瘤性与非肿瘤性病变的敏感性为88.2%,特异性为83.6%,阳性预测值为95.5%,阴性预测值为64.4%,准确度为87.3%,阳性相似比为5.4,阴性相似比为0.1。结论高清非放大结肠镜下贴近观察结合NBI显像观察息肉表面形态对于鉴别大肠息肉是否为肿瘤性有重要价值,与病理诊断有较好的符合率,有助于决定进一步治疗及随访方案。
