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同步数据流语言可信编译器的研究进展 预览 被引量:1
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作者 杨萍 王生原 《计算机科学》 CSCD 北大核心 2019年第5期21-28,共8页
同步数据流语言(如Lustre,Signal)近年来在航空、高铁、核电等安全关键领域得到了广泛应用,因此与这类语言相关的开发工具本身的安全性问题受到高度关注.同步数据流语言到串行命令式语言的可信编译器是此类工具的典型代表(如Scade).构... 同步数据流语言(如Lustre,Signal)近年来在航空、高铁、核电等安全关键领域得到了广泛应用,因此与这类语言相关的开发工具本身的安全性问题受到高度关注.同步数据流语言到串行命令式语言的可信编译器是此类工具的典型代表(如Scade).构造可信编译器的途径可分为两大类:一类是传统的方法,例如通过大量测试和严格的过程管理等手段来实现;另一类是通过形式化方法,例如直接对编译器本身进行形式化证明,采用翻译确认的方法等.近年来,形式化方法作为构造和验证可信编译器的关键途径而得到广泛的重视,有望最大限度地解决“误编译”问题,因而成为新的研究热点.文章在介绍可信编译器的形式化构造和验证方法的基础上,特别聚焦于同步数据流语言可信编译器的相关研究工作,对其现状进行综述和分析. 展开更多
关键词 同步数据流语言 经过验证的编译器 翻译确认 LUSTRE SIGNAL
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Preliminary analysis of echolocation signals produced by fleeing Irrawaddy dolphins (Orcaella brevirostris) 预览
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作者 Ying Jiang Xuelei Zhang +4 位作者 Zhiguo Yang Saifullah Arifin Jaaman Qinzeng Xu Azmi Marzuki Muda Hairul Masrini Muhamad 《海洋学报:英文版》 SCIE CAS CSCD 2019年第1期85-89,共5页
In this study, echolocation signals were recorded from a wild Irrawaddy dolphin (Orcaella brevirostris) in shallow water in the Bay of Brunei. During sound recording, a small fishing boat engine startled a nearby Irra... In this study, echolocation signals were recorded from a wild Irrawaddy dolphin (Orcaella brevirostris) in shallow water in the Bay of Brunei. During sound recording, a small fishing boat engine startled a nearby Irrawaddy dolphin and began chasing it on two occasions. Variations in the acoustic parameters were detected. When the Irrawaddy dolphin was startled and chased, the sound pressure level, number of click trains per minute, pulse number, and average inter-pulse interval (PI) per click train were all affected. The PI increased and exhibited a slight downward trend during the chase. The increase in PI indicated an increase in the inspection distance as the dolphin escaped. Thus, Irrawaddy dolphins may adapt their echolocation signals to stand out from ambient noise in the wild and to improve their search efforts in potentially risky situations. Appropriate management of the burst noise around the dolphins is important. 展开更多
关键词 CLICK TRAIN ECHOLOCATION SIGNAL Irrawaddy DOLPHIN SIGNAL change
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Effects of astragalus injection on the skin lesion degree and Caspase-14,SOCS1 and STAT3 levels of psoriasis model in Balb/c nude mice
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作者 Jin He Heng-Guang Zhao +2 位作者 Xian-Zhi Ren Ya-Ting Chen Yan-Xia Tao 《海南医科大学学报(英文版)》 2019年第6期11-14,共4页
Objective: To investigate the effect of Astragalus Injection on the Skin Lesion Degree and Caspase-14, SOCS1 and STAT3 Levels of Psoriasis Model in Balb/c Nude Mice. Methods:Sixty Balb/c nude mice were randomly divide... Objective: To investigate the effect of Astragalus Injection on the Skin Lesion Degree and Caspase-14, SOCS1 and STAT3 Levels of Psoriasis Model in Balb/c Nude Mice. Methods:Sixty Balb/c nude mice were randomly divided into groups A, B and C with 20 mice in each group. Group A mice were used as blank control, group B mice as model group and group C mice as treatment group. The PASI score of psoriasis, skin thickness, inflammatory factors, serum levels of Caspase-14, SOCS1 and STAT3 in three groups of mice were analyzed after 2 weeks of treatment. Result: After treatment, the P ASI score of group B was significantly higher than that of group C, with statistical significance (P < 0.05);there was statistical significance in the measurements of lesion skin of three groups of mice after treatment (P <0.05). Compared with the blank control group, the thickness of lesion skin in group B and C was significantly higher, and the thickness of lesion skin in treatment group was significantly lower than that in control group (P < 0.05). Compared with the blank control group, the inflammatory factors IL-17, IL-22 and IL-23 in the B and C groups were significantly increased, and the inflammatory factors IL-17, IL-22 and IL-23 in the treatment group were significantly lower than those in the model group. The levels of serum C aspase-14, SOCS1 and STAT3 in three groups of mice were significantly different after treatment (P < 0.05). Compared with the blank control group, the levels of serum C aspase-14 and SOCS1 in B and C groups were significantly lower and the levels of STAT3 were significantly higher, and the levels of inflammatory factors aspase-14 and SO in treatment group were significantly higher than those in control group. The level of CS1 was significantly lower than that of model group, and the level of STAT3 was significantly higher than that of model group (P <0.05). Conclusion: Astragalus membranaceus injection can effectively improve the degree of psoriasis in Balb/c nude mice. Its possible mechanism is that it can 展开更多
关键词 ASTRAGALUS membranaceus injection PSORIASIS CYSTEINE ASPARTATE protease 14 Cytokine SIGNAL TRANSDUCTION inhibitor 1 SIGNAL TRANSDUCTION and transcription activation factor 3
Breast Lump Recognition Algorithms Based on Ultrasound Radio‑Frequency Signals 预览
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作者 YAN Yu CAI Xiaowei +2 位作者 ZHU Wei CAI Runqiu WU Yiyun 《南京航空航天大学学报:英文版》 EI CSCD 2019年第4期635-640,共6页
A method for evaluating the benign and malignant breast tumors based on radio‑frequency(RF)data was explored by extracting the characteristic parameters of breast ultrasound RF signals.The breast biopsy data were used... A method for evaluating the benign and malignant breast tumors based on radio‑frequency(RF)data was explored by extracting the characteristic parameters of breast ultrasound RF signals.The breast biopsy data were used as the reference data for judging the lump benign or malignant.The extracted ultrasound RF data were reconstructed and segmented by computer aided method to obtain the breast tumor region of interest(ROI)and its characteristic parameters(entropy and standard deviation).The characteristic parameters were statistically analyzed to evaluate the relationship between characteristic parameters and benign or malignant breast tumors.The results indicate the entropy and standard deviation of normal region is much higher than that of lump region,which shows that the standard deviation and entropy characteristic parameters of ultrasonic RF signals are meaningful in the diagnosis of breast tumors.The proposed method provides a new direction for computer‑aided diagnosis of benign and malignant breast tumors. 展开更多
关键词 ultrasound radio‑frequency signal breast lump signal processing standard deviation ENTROPY
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Automatic de-noising and recognition algorithm for drilling fluid pulse signal 预览
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作者 HU Yongjian HUANG Yanfu LI Xianyi 《石油勘探与开发:英文版》 2019年第2期393-400,共8页
Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and ins... Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and instruction signal. Two-stage de-noising processing can reduce the impact of baseline drift and determine automatic peak detection threshold range for signal recognition by distinguishing different features of frame synchronization pulse and instruction pulse. Rising and falling edge relative protruding threshold is defined for peak detection in signal recognition, which can make full use of the degree of the signal peak change and detect peaks flexibly with rising and falling edge relative protruding threshold combination. A synchronous decoding method was designed to reduce position uncertainty of the frame synchronization pulse and eliminate the accumulative error of time base drift, which determines the first instruction pulse position according to position of the frame synchronization pulse and decodes subsequent instruction pulse by taking current instruction pulse as new bit synchronization pulse. Special tool software was developed to tune algorithm parameters, which has a decoding success rate of about 95% for the universal coded signals. For the special coded signals with check byte, decoding success rate using the automatic threshold adjustment algorithm is as high as 99%. 展开更多
关键词 drilling fluid pulse SIGNAL SIGNAL processing DECODING success rate AUTOMATIC DE-NOISING and recognition wavelet FORCED DE-NOISING peak detection SYNCHRONOUS DECODING
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The Seasonal Variation of Large Volume Airgun Signals in Hutubi,Xinjiang 预览
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作者 SU Jinbo WANG Qiong +3 位作者 ZHANG Wenxiu WEI Yunyun CHEN Hao WANG Haitao 《中国地震研究:英文版》 CSCD 2019年第2期186-194,共9页
In order to study the seasonal variation of large volume airgun signals in Hutubi,Xinjiang,we analyzed 2,936 signals of airgun source excitations during 2015-2016 received by a seismograph on the bank of the excitatio... In order to study the seasonal variation of large volume airgun signals in Hutubi,Xinjiang,we analyzed 2,936 signals of airgun source excitations during 2015-2016 received by a seismograph on the bank of the excitation pool.Firstly,the RMS value of the signal amplitude and the daily average temperature were compared after linearly superimposing the signal in days,to analyze the influence of the surface ice cover on the excitation energy release of the airgun source.The result shows that the ice cover will reduce the excitation energy,and the thicker the ice cover is,the more obvious the excitation energy reduces.Secondly,the time-frequency analysis method was used to analyze the influence of the surface ice cover on the signal frequency.It is concluded that the existence of the ice cover has little effect on the signal frequency,but it will affect the intensity of the signal around 4 Hz between 1-2 s after excitation.The cause of these phenomena is that the ice cover affects the bubble oscillation,which in turn affects the energy conversion.The study shows that when using the cross-correlation delay method to calculate the wave velocity,the signals can be divided into two periods according to the daily average temperature:with or without ice cover on the upper surface of the excitation pool.This can help eliminate the influence of the source variation and improve the accuracy of the monitoring results. 展开更多
关键词 airgun source SEASONAL VARIATION SIGNAL energy SIGNAL FREQUENCY
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Effects of winter weather on traffic operations and optimization of signalized intersections
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作者 Zhengyang Lu Tae J.Kwon Liping Fu 《交通运输工程学报(英文版)》 CSCD 2019年第2期196-208,共13页
Adverse winter weather has always been a cause of traffic congestion and road collisions.To mitigate the negative impacts of winter weather, transportation agencies are under increasing pressure to introduce weather r... Adverse winter weather has always been a cause of traffic congestion and road collisions.To mitigate the negative impacts of winter weather, transportation agencies are under increasing pressure to introduce weather responsive traffic management strategies.Currently, most traffic signal control systems are designed for normal weather conditions and are therefore suboptimal regarding efficiency and safety for controlling traffic during winter snow events due to changes in traffic patterns and driver behaviors. The main objective of this research is to explore how to modify pre-timed traffic signal control parameters under adverse weather conditions to increase traffic efficiency and road safety.This research consists of two main components. First, we examine the impacts of winter weather on three key traffic parameters, i.e., saturation flow rate, start-up lost time, and free flow speed. Secondly, we investigate the potential benefits of implementing weatherspecific signal control plans for uncoordinated intersections as well as coordinated corridors. Two case studies are conducted, each with varying levels of traffic demand and winter event severity, to compare the performance of different signal plans. Evaluation results from both Synchro and VISSIM show that implementing such signal plans is most beneficial for intersection with a medium level of traffic demand. It is also found that the benefit of implementing weather-responsive plans was more compelling at a coordinatedcorridor level than at an uncoordinated-intersection level. 展开更多
关键词 SIGNAL OPTIMIZATION Inclement WEATHER TRAFFIC simulation SIGNAL COORDINATION
Quality monitoring and biases estimation of BOC navigation signals 预览
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作者 ZHAO Hongwei ZHANG Zichun +1 位作者 LUO Xianzhi WANG Qiuping 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第3期474-484,共11页
Many safety-critical applications that utilize the global navigation satellite system (GNSS) demand highly accurate positioning information, as well as highly integrity and reliability. Due to GNSS signals are easily ... Many safety-critical applications that utilize the global navigation satellite system (GNSS) demand highly accurate positioning information, as well as highly integrity and reliability. Due to GNSS signals are easily distorted by the interferences or disturbances, the signal quality monitoring (SQM) is necessary to detect the presence of dangerous signal distortions. In this paper, we developed an SQM software for binary offset carrier (BOC) modulated navigation signals. Firstly, the models of BOC signal with ideal and distortion are presented respectively. Then the architecture of SQM software is proposed. Moreover, the effect of the white gaussian noise (WGN) and the front-end filter on the correlation peak of the receiver is analyzed. Finally, the biases induced by the signal distortion are evaluated. The experiments simulate the relationships between the code phase shift and the normalized correlation value in the case of the signal digital distortion and the analog distortion. The simulation results demonstrate that the proposed SQM method can effectively monitor the signal distortion and accurately estimate the correlation peak deviation caused by the distortion. 展开更多
关键词 SIGNAL quality monitoring (SQM) binary OFFSET carrier (BOC) modulation biases estimation SIGNAL DISTORTION correlation peak
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Weak Seismic Signal Extraction Based on the Curvelet Transform 预览
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作者 TAN Junqing YANG Runhai +1 位作者 WANG Bin XIANG Ya 《中国地震研究:英文版》 CSCD 2019年第2期220-234,共15页
Seismic signal denoising is a key step in seismic data processing.Airgun signals are easy to be interfered with by noise when it travels a long distance due to the weak energy of active source signal of the airgun.Aim... Seismic signal denoising is a key step in seismic data processing.Airgun signals are easy to be interfered with by noise when it travels a long distance due to the weak energy of active source signal of the airgun.Aiming to solve this problem,and considering that the conventional Curvelet transform threshold processing method does not use the seismic spectrum information,we independently process the Curvelet scale layer corresponding to valid data based on the characteristics of the Curvelet transform of multi-scale,multi-direction and capable of expressing the sparse seismic signals in order to fully excavate the information features.Combined with the Curvelet adaptive threshold denoising the algorithm,we apply the Curvelet transform to denoising seismic signals while retaining the weak information in the signal as much as possible.The simulation experiments show that the improved threshold denoising method based on Curvelet transform is superior to the frequency domain filtering,wavelet denoising and traditional Curvelet denoising method in detailed information extraction and signal denoising of low SNR signals.The calculation accuracy of the relative wave velocity variation of underground medium is improved. 展开更多
关键词 Seismic SIGNAL DENOISING Airgun active source SIGNAL CURVELET TRANSFORM The velocity of the UNDERGROUND medium
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Improving Airgun Signal Detection with Small-Aperture Seismic Array in Yunnan 预览
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作者 WANG Weijun ZHOU Qingyun +3 位作者 KOU Huadong LIU Guiping ZHU Hongbo YAN Kun 《中国地震研究:英文版》 CSCD 2019年第2期248-264,共17页
Repeating airgun sources are eco-friendly sources for monitoring the changes in the physical properties of subsurface mediums,but their signals decay quickly and are buried in the noises soon after traveling short dis... Repeating airgun sources are eco-friendly sources for monitoring the changes in the physical properties of subsurface mediums,but their signals decay quickly and are buried in the noises soon after traveling short distances.Stacking waveforms from different airgun shots recorded by a single seismic station(shot stacking)is the most popular technique to detect weak signals from noisy backgrounds,and has been widely used to process the data of Fixed Airgun Signal Transmission Stations(FASTS)in China.However,shot stacking sacrifices the time resolution in monitoring to recover a qualified airgun signal by stacking many shots at distance stations,and also suffers from persistent local noises.In this paper,we carried out several small-aperture seismic array experiments around the Binchuan FAST Station(BCFASTS)in Yunnan Province,China,and applied the array technique to improve airgun signal detection.The results show that seismic array processing combining with shot stacking can suppress seismic noises more efficiently,and provide better signal-to-noise ratio(SNR)and coherent airgun signals with less airgun shots.This work suggests that the array technique is a feasible and promising tool in FAST to increase the time resolution and reduce noise interference on routine monitoring. 展开更多
关键词 Airgun SIGNAL Detection Small-Aperture SEISMIC Array Binchuan Fixed Airgun SIGNAL Transmission Stations(BCFASTS)
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Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico
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作者 Pedro PONCE Therese PEFFER Arturo MOLINA 《能源前沿:英文版》 CSCD 2019年第3期522-538,共17页
It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. ... It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids. 展开更多
关键词 THERMOSTATS PERCEPTIONS BELIEFS SIGNAL DETECTION THEORY (SDT) fuzzy SIGNAL DETECTION THEORY (FSDT) chi-square (CS) test
A Frequency Domain Based Signal Combining Method for Distributed Antenna Arraying 预览
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作者 Chaowei Duan Yafeng Zhan Qian Kong 《中国通信:英文版》 SCIE CSCD 2019年第8期176-184,共9页
Distributed antenna arraying is a promising technology for weak signal reception. The received signals from different antennas are aligned and combined to improve the receiving signal-to-noise ratio(SNR). However, the... Distributed antenna arraying is a promising technology for weak signal reception. The received signals from different antennas are aligned and combined to improve the receiving signal-to-noise ratio(SNR). However, the combining performance is serious degraded by the difference of sampling frequency between antennas. In this paper, a frequency domain based signal combining method is proposed to solve this problem. The unaligned sampled data in time domain of the received signals are transformed to frequency domain using fast Fourier transform(FFT). The received signals can be aligned in frequency domain when their spectrum resolutions are the same. Therefore the received signals with the same total sampling time can be aligned and combined in frequency domain and then the combined signal is recovered using inverse fast Fourier transform(IFFT). Numerical simulations with two typical modulation types, i.e., PSK and PCM/BPSK/PM, prove the validity and robustness of this method. 展开更多
关键词 WEAK SIGNAL RECEPTION DISTRIBUTED antenna arraying SIGNAL combining fast FOURIER TRANSFORM
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High Resolution Radar Real-Time Signal and Information Processing 预览
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作者 Teng Long Tao Zeng +8 位作者 Cheng Hu Xichao Dong Liang Chen Quanhua Liu Yizhuang Xie Zegang Ding Yang Li Yanhua Wang Yan Wang 《中国通信:英文版》 SCIE CSCD 2019年第2期105-133,共29页
Radar is an electronic device that uses radio waves to determine the range,angle,or velocity of objects.Real-time signal and information processor is an important module for real-time positioning,imaging,detection and... Radar is an electronic device that uses radio waves to determine the range,angle,or velocity of objects.Real-time signal and information processor is an important module for real-time positioning,imaging,detection and recognition of targets.With the development of ultra-wideband technology,synthetic aperture technology,signal and information processing technology,the radar coverage,detection accuracy and resolution have been greatly improved,especially in terms of one-dimensional(1D)high-resolution radar detection,tracking,recognition,and two-dimensional(2D)synthetic aperture radar imaging technology.Meanwhile,for the application of radar detection and remote sensing with high resolution and wide swath,the amount of data has been greatly increased.Therefore,the radar is required to have low-latency and real-time processing capability under the constraints of size,weight and power consumption.This paper systematically introduces the new technology of high resolution radar and real-time signal and information processing.The key problems and solutions are discussed,including the detection and tracking of 1D high-resolution radar,the accurate signal modeling and wide-swath imaging for geosynchronous orbit synthetic aperture radar,and real-time signal and information processing architecture and efficient algorithms.Finally,the latest research progress and representative results are presented,and the development trends are prospected. 展开更多
关键词 1D high RESOLUTION RADAR geosynchronous SYNTHETIC APERTURE RADAR REAL-TIME SIGNAL and information processing
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Weak signal direction of arrival estimation for colocated multiple-input multiple-output sonar array
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作者 CHENG Xue WANG Yingmin 《声学学报:英文版》 CSCD 2019年第3期253-272,共20页
In order to suppress the influence of symmetrical noise component on multiple-input multiple-output(MIMO)sonar’s direction of arrival(DOA)estimation under the condition of low signal-to-noise ratio,we propose a DOA e... In order to suppress the influence of symmetrical noise component on multiple-input multiple-output(MIMO)sonar’s direction of arrival(DOA)estimation under the condition of low signal-to-noise ratio,we propose a DOA estimation algorithm based on covariance matrix reconstruction method.Firstly,the noise field can be decomposed into symmetrical noise field and asymmetrical noise field.We utilize symmetry property of colored noise matrix and the feature that the imaginary part of covariance matrix has no relation with the symmetry noise to remove the real part of covariance matrix.This operation helps to suppress the influence of colored noise on DOA estimation accuracy.Based on the principle of the imaginary matrix part displacement and the dimension reduction transformation method,the real part of covariance matrix is reconstructed,which helps to suppress the bilateral spectrum interference.Thereafter,Toeplitz method is applied for the covariance matrix decorrelation amendment,and a noise subspace is formed by singular value decomposition(SVD).Finally,we can estimate the DOA of target signals.Both theoretical analysis results and numerical simulation results verify the symmetrical noise suppression performance of this algorithm,and the estimation performance of target azimuth is improved obviously.This method has the characteristics of lower operational complexity,higher degrees of freedom and stronger target resolution. 展开更多
关键词 DOA WEAK signal direction of ARRIVAL estimation for colocated MULTIPLE-INPUT multiple-output SONAR ARRAY
Deceptive Chinese speech detection based on sparse decomposition of cepstral feature
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作者 FAN Xiaohe ZHAO Heming +1 位作者 CHEN Xueqin ZHOU Yan 《声学学报:英文版》 CSCD 2019年第1期99-112,共14页
In order to improve the performance of deception detection based on Chinese speech signals,a method of sparse decomposition on spectral feature is proposed.First,the wavelet packet transform is applied to divide the s... In order to improve the performance of deception detection based on Chinese speech signals,a method of sparse decomposition on spectral feature is proposed.First,the wavelet packet transform is applied to divide the speech signal into multiple sub-bands.Band cepstral features of wavelet packets are obtained by operating the discrete cosine transform on logarithmic energy of each sub-band.The cepstral feature is generated by combing Mel Frequency Cepstral Coefficient and Wavelet Packet Band Cepstral Coefficient.Second,K-singular value decomposition algorithm is employed to achieve the training of an over-complete mixture dictionary based on both the truth and deceptive feature sets,and an orthogonal matching pursuit algorithm is used for sparse coding according to the mixture dictionary to get sparse feature. Finally,recognition experiments are performed with various classified modules.Experimental results show that the sparse decomposition method has better performance comparied with conventional dimension reduced methods.The recognition accuracy of the method proposed in this paper is 78.34%,which is higher than methods using other features,improving the recognition ability of deception detection system significantly. 展开更多
关键词 CEPSTRUM FEATURES VOICE DETECTION Chinese SPEECH signal
Quantum dots enhanced Cerenkov luminescence imaging 预览
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作者 Chang-Ran Geng Yao Ai +4 位作者 Xiao-Bin Tang Di-Yun Shu Chun-Hui Gong Ming-Hua Du Fa-Quan Ji 《核技术:英文版》 SCIE CAS CSCD 2019年第5期9-13,共5页
Cerenkov luminescence imaging (CLI) has been widely investigated for biological imaging. However, the luminescence generated from Cerenkov effect is relatively weak and has poor penetration ability in biological tissu... Cerenkov luminescence imaging (CLI) has been widely investigated for biological imaging. However, the luminescence generated from Cerenkov effect is relatively weak and has poor penetration ability in biological tissues. These limitations consequently hindered the clinical translation of CLI. In this study, we proposed an in vitro experimental study for the demonstration of quantum dots (QDs) configurations affected by the improvement of the signal intensity of CLI. Results revealed that the optimal concentrations were 0.1 mg/mL and 0.25 mg/mL for the studied CdSe/ZnS QDs with fluorescence emission peaks of 580 nm and 660 nm, respectively. The detected optical signal intensity with long-wavelength emission QDs were stronger than those with short-wavelength emission QDs. This study illustrates an experiment to study the effects of concentrations and fluorescence emission peaks of QDs on an enhanced optical signal for the external detection of CLI. 展开更多
关键词 CERENKOV LUMINESCENCE IMAGING Quantum DOTS Optical signal WAVELENGTH shift
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Not all arrestins are created equal:Therapeutic implications of the functional diversity of the β-arrestins in the heart 预览
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作者 Anastasios Lymperopoulos Shelby L Wertz +3 位作者 Celina M Pollard Victoria L Desimine Jennifer Maning Katie A McCrink 《世界心脏病学杂志:英文版(电子版)》 2019年第2期47-56,共10页
The two ubiquitous,outside the retina,G protein-coupled receptor(GPCR)adapter proteins,β-arrestin-1 and-2(also known as arrestin-2 and-3,respectively),have three major functions in cells:GPCR desensitization,i.e.,rec... The two ubiquitous,outside the retina,G protein-coupled receptor(GPCR)adapter proteins,β-arrestin-1 and-2(also known as arrestin-2 and-3,respectively),have three major functions in cells:GPCR desensitization,i.e.,receptor decoupling from G-proteins;GPCR internalization via clathrin-coated pits;and signal transduction independently of or in parallel to G-proteins.Bothβ-arrestins are expressed in the heart and regulate a large number of cardiac GPCRs.The latter constitute the single most commonly targeted receptor class by Food and Drug Administration-approved cardiovascular drugs,with about onethird of all currently used in the clinic medications affecting GPCR function.Sinceβ-arrestin-1 and-2 play important roles in signaling and function of several GPCRs,in particular of adrenergic receptors and angiotensin II type 1 receptors,in cardiac myocytes,they have been a major focus of cardiac biology research in recent years.Perhaps the most significant realization coming out of their studies is that these two GPCR adapter proteins,initially thought of as functionally interchangeable,actually exert diametrically opposite effects in the mammalian myocardium.Specifically,the most abundant of the two β-arrestin-1 exerts overall detrimental effects on the heart,such as negative inotropy and promotion of adverse remodeling post-myocardial infarction(MI).In contrast,β-arrestin-2 is overall beneficial for the myocardium,as it has anti-apoptotic and antiinflammatory effects that result in attenuation of post-MI adverse remodeling,while promoting cardiac contractile function.Thus,design of novel cardiac GPCR ligands that preferentially activateβ-arrestin-2 overβ-arrestin-1 has the potential of generating novel cardiovascular therapeutics for heart failure and other heart diseases. 展开更多
关键词 Adverse remodeling β-arrestin Biased signaling CARDIAC MYOCYTE CARDIAC fibroblast CONTRACTILITY Functional divergence G protein-coupled receptor HEART failure Hormone Myocardial infarction Signal transducer
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Analysis of Pulse Signals Based on Array Pulse Volume
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作者 CUI Ji TU Li-ping +3 位作者 ZHANG Jian-feng ZHANG Shao-liang ZHANG Zhi-feng XU Jia-tuo 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第2期103-107,共5页
Objective: To collect and analyze multi-dimensional pulse diagram features with the array sensor of a pressure profile system(PPS) and study the characteristic parameters of the new multi-dimensional pulse diagram by ... Objective: To collect and analyze multi-dimensional pulse diagram features with the array sensor of a pressure profile system(PPS) and study the characteristic parameters of the new multi-dimensional pulse diagram by pulse diagram analysis technology. Methods: The pulse signals at the Guan position of left wrist were acquired from 105 volunteers at the Shanghai University of Traditional Chinese Medicine. We obtained the pulse data using an array sensor with 3×4 channels. Three dimensional pulse diagrams were constructed for the validated pulse data, and the array pulse volume(APV) parameter was computed by a linear interpolation algorithm. The APV differences among normal pulse(NP), wiry pulse(WP) and slippery pulse(SP) were analyzed using one-way analysis of variance. The coefficients of variation(CV) were calculated for WP, SP and NP. Results: The APV difference between WP and NP in the 105 volunteers was statistically significant(6.26±0.28 vs. 6.04±0.36, P=0.048), as well as the difference between WP and SP(6.26±0.28 vs. 6.07±0.46, P=0.049). However, no statistically significant difference was found between NP and SP(P=0.75). WP showed a similar CV(4.47%) to those of NP(5.96%) and SP(7.58%). Conclusion: The new parameter APV could differentiate between NP or SP and WP. Accordingly, APV could be considered an useful parameter for the analysis of array pulse diagrams in Chinese medicine. 展开更多
关键词 PULSE SIGNAL ARRAY PULSE VOLUME PULSE SENSOR Chinese MEDICINE
Development of readout electronics for bunch arrival-time monitor system at SXFEL 预览
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作者 Jin-Guo Wang Bo Liu 《核技术:英文版》 SCIE CAS CSCD 2019年第5期113-121,共9页
A bunch arrival-time monitor (BAM) system, based on electro-optical intensity modulation scheme, is under study at Shanghai Soft X-ray Free Electron Laser. The aim of the study is to achieve high-precision time measur... A bunch arrival-time monitor (BAM) system, based on electro-optical intensity modulation scheme, is under study at Shanghai Soft X-ray Free Electron Laser. The aim of the study is to achieve high-precision time measurement for minimizing bunch fluctuations. A readout electronics is developed to fulfill the requirements of the BAM system. The readout electronics is mainly composed of a signal conditioning circuit, field-programmable gate array (FPGA), mezzanine card (FMC150), and powerful FPGA carrier board. The signal conditioning circuit converts the laser pulses into electrical pulse signals using a photodiode. Thereafter, it performs splitting and low-noise amplification to achieve the best voltage sampling performance of the dual-channel analog-to-digital converter (ADC) in FMC150. The FMC150 ADC daughter card includes a 14-bit 250 Msps dual-channel high-speed ADC, a clock configuration, and a management module. The powerful FPGA carrier board is a commercial high-performance Xilinx Kintex-7 FPGA evaluation board. To achieve clock and data alignment for ADC data capture at a high sampling rate, we used ISERDES, IDELAY, and dedicated carry-in resources in the Kintex-7 FPGA. This paper presents a detailed development of the readout electronics in the BAM system and its performance. 展开更多
关键词 BUNCH arrival-time monitor (BAM) Shanghai Soft X-ray Free Electron Laser (SXFEL) Fieldprogrammable gate array (FPGA) Signal CONDITIONING High-speed analog-to-digital converter (ADC)
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A dispersion flattened fiber front-haul transmission system with high bitrate signal at low input optical power
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作者 王潇 朱龙洋 +4 位作者 郑宏军 黎昕 白成林 胡卫生 许恒迎 《光电子快报:英文版》 EI 2019年第1期31-34,共4页
We propose a dispersion flattened fiber (DFF) front-haul transmission system with high bitrate, polarization multiplexing (PM) and quadrature amplitude modulation (QAM) signal at low input optical power. The modulatio... We propose a dispersion flattened fiber (DFF) front-haul transmission system with high bitrate, polarization multiplexing (PM) and quadrature amplitude modulation (QAM) signal at low input optical power. The modulation format of the system is PM-16 QAM, and the bitrate is 256 Gbit/s. The transmission characteristics over DFF link system are experimentally studied, which are compared with those over non-zero dispersion shifted fiber (NZDSF) link and standard single mode fiber (SSMF) link. The experimental results show that the error vector magnitude(EVM) of 256 Gbit/s and PM-16 QAM signal over 25 km DFF link is 0.75% better than that over 25 km NZDSF link at least, and the bit error rate (BER) and Q-factor are much better than those of NZDSF. Their EVM and BER are both decreased with the increase of input optical power, and the Q-factor is increased. Those characteristics over 25 km SSMF are the worst at the same case. The larger the dispersion is, the more the constellation points are deviated from their respective centers and the worse the constellation characteristics are. The greater the attenuation of the DFF is, the smaller the input power of the DFF is, the more the constellation points are deviated from their centers and the worse the constellation characteristics are. This study provides a new idea and experimental support for long span front-haul propagation in mobile communication. 展开更多
关键词 DISPERSION transmission SIGNAL
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