水下报文通信抗干扰方法

针对水声通信中的衰减信道和多途效应对报文通信的影响,利用混沌编码方式以获取处理增益,并利用拷贝相关器对信道进行估值的基础上,提出了用相干重置的方法对多途效应加以利用,以降低误码率.仿真结果表明,相干重置的方法相对于直接相关解码方法具有更低的误码率.由此可见,以上的方法对减少多途干扰的影响是有明显的效果的.水声通信一般部...     

单片机心电呼吸通气量监测系统

介绍一种由单片机实现的心电呼吸通气量监测系统的硬件构成和软件设计。该系统基于阻抗法,实现了对呼吸潮气量的无创连续测量,并具有心电监测功能。系统采用先进的数字存储示波技术,其硬件构成模块化,通过引入逐个定标的方法,克服了测量呼吸潮气量的个体差异,使阻抗法测量呼吸通气量成为实际可行。     

Sea surface wind speed and sea state retrievals from dual-frequency altimeter and its preliminary application in global view of wind-sea and swell distributions

Altimeter radar backscatter intensity, in terms of the normalized radar cross section (NRCS), is known to be modulated by surface wind forcing and the state of wind-sea development. Based on a data set of collocated altimeters (including Topex/Poseidon, Jason-1 and Jason-2) and in situ measurements, different responses to various wind speeds and wave ages (i.e. the state of wind-sea development) were illustrated for altimeter dual-frequency NRCSs (K_u-band at 13.6 Hz and C band at 5.4 Hz), which can facilitate the retrieval of wind speed and wave age parameters. A statistical parametric algorithm was developed to retrieve the two dynamic parameters from the altimeter dual-frequency NRCSs using the neutral network method. The wind-sea significant wave height (SWH) was estimated from wind speed and wave age parameters, which partitions the swell SWH from the altimeter SWH measurement. All newly derived parameters were well validated by comparison against in situ buoy measurements. A preliminary application of the method in examining the swell or wind-sea contributions to global waves was performed; it was found the swell dominance in an open ocean, and the wind-sea dominance in marginal and semi-enclosed seas. The methods would benefit other applications such as studies of air–sea interactions, validation of wave model, determination of swell decay rate and studies of wave climate.     

无线镀膜玻璃色差数据实时监测系统的设计

针对玻璃生产线布线困难、电磁干扰强、数据处理效率低的状况,设计了无线镀膜玻璃色差数据实时监测系统;介绍了无线射频收发芯片nRF2401AG的原理及特点,采用了无线通信技术和数据库技术,阐述了将Visual C++6.0作为开发平台,镀膜玻璃色差数据无线收发、实时监测、实时存储、动态显示等实现过程;经实际验证:该系统无线通信稳定可靠、数据处理效率高;满足了工程实际应用需求,具有很好的实用性和推广价值。     

软PLC控制系统实现

以Visual C 6.0作为开发工具,介绍了软PLC控制系统的软、硬件结构,详细叙述了其具体实施方案,并给出实际运用,验证了它的正确性.     

New robust exponential stability analysis for uncertain neural networks with time-varying delay

In this paper, the global robust exponential stability is considered for a class of neural networks with parametric uncer-tainties and time-varying delay. By using Lyapunov functional method, and by resorting to the new technique for estimating the upper bound of the derivative of the Lyapunov functional, some less conservative exponential stability criteria are derived in terms of linear matrix inequalities (LMIs). Numerical examples are presented to show the effectiveness of the proposed method.     

汽车失效催化剂预处理方法研究

系统研究了原料粒度、品位、酸度、液固比、浸出温度、浸出时间、氧化剂用量及溶液电势、预处理方法对汽车失效催化剂中铂族金属浸出率的影响。结果表明,在粒度-0.074mm、液固比L/S=5/1、90~100℃、控制溶液电势1.0~1.2V氯化浸出8h,原料品位愈高,渣率愈低,浸出率愈高;随着盐酸和硫酸混合酸浓度的增加,铂族金属的浸出率急剧升高并且均高于单一的盐酸和硫酸介质。添加硫酸氢钠焙烧预处理(300℃,3h)能显著提高铂族金属尤其是铑的浸出率,铂、钯的浸出率大于99%,铑的浸出率大于97%。     

An Efficient WRF Framework for Discovering Risk Genes and Abnormal Brain Regions in Parkinson’s Disease Based on Imaging Genetics Data

As an emerging research field of brain science,multimodal data fusion analysis has attracted broader attention in the study of complex brain diseases such as Parkinson's disease (PD).However,current studies primarily lie with detecting the association among different modal data and reducing data attributes.The data mining method after fusion and the overall analysis framework are neglected.In this study,we propose a weighted random forest (WRF) model as the feature screening classifier.The interactions between genes and brain regions are detected as input multimodal fusion features by the correlation analysis method.We implement sample classification and optimal feature selection based on WRF,and construct a multimodal analysis framework for exploring the pathogenic factors of PD.The experimental results in Parkinson's Progression Markers Initiative (PPMI) database show that WRF performs better compared with some advanced methods,and the brain regions and genes related to PD are detected.The fusion of multi-modal data can improve the classification of PD patients and detect the pathogenic factors more comprehensively,which provides a novel perspective for the diagnosis and research of PD.We also show the great potential of WRF to perform the multimodal data fusion analysis of other brain diseases.     

Detecting Vulnerability on IoT Device Firmware: A Survey

Internet of things (IoT) devices make up 30%of all network-connected endpoints,introducing vulnerabilities and novel attacks that make many companies as primary targets for cybercriminals.To address this increasing threat surface,every organization deploying IoT devices needs to consider security risks to ensure those devices are secure and trusted.Among all the solutions for security risks,firmware security analysis is essential to fix software bugs,patch vulnerabilities,or add new security fea...