An Analysis of Average Pulsar Profiles and A Study of the ρ-P relation of Pulsars

Using the method of Gaussian Fit Separation of Average Profile (GF-SAP), we re-examine the average profiles of nine pulsars at several frequencies, ranging from 408-1642 MHz. This method enables us to obtain the number of components for each pulsar, and the parameters for each component, the width, position and amplitude. The ρ-P relation for the inner cone and outer cone are studied separately, and the results are, respectively, ρ = p-0.51±0.05 and ρ= p-0.42±0.06 The results can be interpreted as a confirmation of the double-cone structure of pulsar emission beams. The altitudes of emission region, and the radius-to-frequency-map (RFM) are also examined; for the outer cone, we obtained γ(v) ∝v-0.19±0.09.

An Integrated Analysis Method for miRNA, lncRNA and mRNA Profiles Based on Their Functional and Positional Relationships

ncRNAs have been identified as potential regulatory molecules and have multiple biological roles. Aberrant expression of specific ncRNAs contributes to multiple biological processes and many human diseases. Herein, we simultaneously profiled miRNA, lncRNA and mRNA in human HepG2 and L02 cells applying high-throughput sequencing and micro-array technologies. Abnormal miRNA, lncRNA and mRNA profiles were assessed through fold change filtering. A cross-platform integrated analysis method was developed to analyze differentially expressed miRNA, lncRNA and mRNA profiles. miRNA-mRNA interaction was analyzed according to their functional relationships. Target mRNAs of aberrantly expressed miRNAs were obtained from experimentally validated datasets or predicted using some programs. Generally, multiple target mRNAs were involved, and they have versatile roles by functional enrichment analysis. Ac-cording to actual expression datasets in the study, compared to deregulated miRNAs, these theoretical target mRNAs showed various expression patterns. The consistent or inconsistent expression was mainly derived from complex, mul-tiple, flexible and alternative regulatory relationships between miRNA and mRNA. Further, miRNA/mRNA and lncRNA were completely surveyed based on their location distributions on human chromosomes. Many miRNA-lncRNA and mRNA-lncRNA pairs always were located on the same strand or different strands in the specific genomic region. Due to the location distributions, they might have partly or completely overlapped regions or they could be reverse complementarily binding. These miRNA/mRNA-lncRNA pairs showed consistent or inconsistent expression pat-terns, although they might have functional relationships through reverse complementarily binding events. Moreover, we also detected and analyzed various isomiRs from a given miRNA locus, including those isomiRs with 3’ additional non-template nucleotides. These isomiRs, especially for those 5’ isomiRs with the new “seed sequences” through “seed shifting” events, maybe have potential biological roles as well as isomiR repertoire and their expression patterns. The integrative analysis provides potential functional relationships between miRNA, lncRNA and mRNA across different datasets. The complex and various expression patterns suggest a robust regulatory network across different regulatory molecules and their targets.

铝合金型材挤压弯曲一体化成形技术研究进展

相比于直型材,铝合金弯曲型材更适用于日益复杂的部件形状并能更好地满足轻量化需求,具有提升部件结构强度和刚度、节约空间及增加工业设计自由度等优点,在汽车、高铁和航空航天等领域具有广泛用途。相较于传统冷弯成形技术,挤压弯曲一体化成形技术在生产弯曲型材方面具有流程短、精度高、缺陷少等优点,因而受到广泛关注。重点综述了基于外部弯曲装置和材料差速流动的挤压弯曲一体化成形技术的研究进展,分析并总结了不同挤压弯曲一体化成形技术的原理及发展现状,对比了不同挤压弯曲一体化成形技术的优缺点,最后展望未来发展趋势及其研究方向。

河套盆地北缘色尔滕山河流地貌参数特征及其成因分析

地貌形态是构造和地表过程相互作用的复杂产物,主要通过构造活动和岩石的抗侵蚀能力等来调节。构造活动相对较弱的古老造山带往往可以忽略构造驱动的岩石抬升,使得研究岩石抗侵蚀能力对其地貌雕刻的贡献成为可能。但是目前大多数活动造山带地貌研究的结果显示地貌主要受控于活动构造,关于岩性对地貌演化影响的报道较少。色尔滕山山前断裂为河套盆地北缘的一条重要控盆断裂,全新世以来该断裂的活动性较强,曾发生过两次较大震级地震(M6.4和M5.9)。前人活动构造研究表明该断裂的活动性具有空间差异,中部乌加河镇活动性最强,两端逐渐减弱。但相对河套盆地北缘其他大型断裂(如狼山山前断裂、乌拉山北缘断裂和大青山山前断裂),该断裂的地貌参数研究较少。同时其地貌演化特征及发育机理仍然不清楚,这些均制约了对该断裂的变形动力学理解。本文基于30 m分辨率的DEM数据对该断裂进行详细的河流地貌学参数研究,包括使用Arcgis和Matlab脚本提取色尔滕山山前33条河流的子流域盆地面积-高程积分(HI)和相应河道陡峭指数(K_(sn))、河道纵剖面及其裂点等地貌学参数。结果表明研究区河流HI值大部分处于0.40~0.66之间,其中乌加河镇附近具有高值,流域盆地处于发育的壮年期。瞬态河道和稳态河道均沿着色尔滕山山前断裂走向分布,可能表明色尔滕山山前大部分河道目前处于瞬时地貌向均衡地貌演化阶段,并且通过对比发现瞬态河道裂点成因存在岩性和构造共同控制的现象。河道陡峭指数空间分布差异性较大,乌加河镇附近(S13~S20)陡峭指数较大,向两边陡峭指数逐渐减小,在S8河流以西又有增大的趋势。通过结合岩性和降雨情况分析发现,河道陡峭指数除了受岩性抗侵蚀能力影响外,其分布还与色尔滕山山前断裂垂直滑移速率分布和垂直位错分布基本一致。综合来看,地貌参数的空间分布是岩性差异和色尔滕山山前断裂活动分段差异性共同控制的结果,表明该地区岩性和构造对地貌的协同塑造作用。

剖面浮标变体积油囊式浮力调节系统设计

为精准控制剖面浮标的垂向运动,提出一种可精确控制油量的变体积油囊式浮力调节系统,包含外油囊、增压油箱、密封性能良好的电磁球阀和可调节转速的液压泵等组件。采用拉线位移传感器实时采集增压油箱液面位置实现油量监控,并对外油囊体积进行高精度闭环反馈控制;设计极低泄漏量的液压系统,实现系统在待机状态下浮力保持长期稳定。为精确控制浮力调节系统,构建控制系统数学模型,引入比例积分微分(Proportional Integral Differential,PID)控制算法,并采用Simulink进行稳定性仿真。试验结果表明,系统可实现浮力精确控制,最大超调量低于1%,稳定性与响应速度均符合预期,验证了控制策略的可靠性。

不同排放标准下汽油车和柴油车挥发性有机物(VOCs)成分谱的建立

挥发性有机物(VOCs)是臭氧和二次有机气溶胶的重要前体物,道路移动源是我国大气VOCs的重要来源之一。本文在调研文献基础上,总结国内道路移动源VOCs成分谱建立方法,包括成分谱实测方法和成分谱整合方法。针对现阶段道路移动源VOCs排放已发展至在燃料的基础上区分排放标准,本文阐述实测条件下不同排放标准汽油车和柴油车的VOCs成分谱,指出现有成分谱的不足之处;对比基于实测数据和基于数据整合的道路移动源VOCs的差异,提出当前需建立统一的采样分析方法,更新现有道路移动源VOCs成分谱数据库。

K波段在片天线设计

基于PCB工艺设计了一款K波段在片天线,天线满足的性能指标:阻抗带宽(|S11|≤-10dB)≥15%,带内最大增益≥12dBi,3dB增益带宽≥10%,副瓣电平抑制≥13dB。提出的在片天线采用单层PCB工艺将基于CPW的馈电端口、基于微带传输线的馈电网络和基于贴片的微带寄生辐射单元集成在一起,具有集成度高、低剖面和低成本的优点,可以被广泛应用于无线局域网通信。

海上风电场地理信息综合服务关键技术

海上风电作为清洁能源,进行大力开发建设。地理信息在海上风电场建设运维、船舶航行安全方面发挥重要作用,也是海事通航尺度核定测量重要内容。海上风电场地理信息综合服务包含侧扫声呐探测、浅地层剖面探测、多波束水深测量及二三维一体化展示等关键技术。本文以粤东某风电场为例,进行了沉船扫海测量、风机基底探测、礁石浅点探测、电缆数据采集及风电场海域相关要素二三维一体化展示。结果表明,风电场地理信息数据需要结合浅地层剖面仪、侧扫声呐和多波束影像综合分析,提高数据的互补性和可靠性;基于潮汐模型与余水位监控法、海量多波束处理CUBE算法具有应用价值,磁法测量、下潜探摸和水下摄像判读可获取沉船更详细的信息。

A Novel Method for the Reconstruction of Road Profiles from Measured Vehicle Responses Based on the Kalman Filter Method

The estimation of the disturbance input acting on a vehicle from its given responses is an inverse problem.To overcome some of the issues related to ill-posed inverse problems,this work proposes a method of reconstructing the road roughness based on the Kalman filter method.A half-car model that considers both the vehicle and equipment is established,and the joint input-state estimation method is used to identify the road profile.The capabilities of this methodology in the presence of noise are numerically demonstrated.Moreover,to reduce the influence of the driving speed on the estimation results,a method of choosing the calculation frequency is proposed.A road vibration test is conducted to benchmark the proposed method.

Calibration of Soil Electromagnetic Conductivity in Inverted Salinity Profiles with an Integration Method

Various calibration methods have been propounded to determine profiles of apparent bulk soil electrical conductivity (ECa) and soil electrical conductivity of a saturated soil paste extract (ECe) or a 1:5 soil water extract (EC1:5) using an electromagnetic induction instrument (EM38). The modeled coefficients, one of the successful and classical methods hitherto, were chosen to calibrate the EM38 measurements of the inverted salinity profiles of characteristic coastal saline soils at selected sites of Xincao Farm, Jiangsu Province, China. However, this method required three parameters for each depth layer. An integration approach, based on an exponential decay profile model, was proposed and the model was fitted to all the calibration sites. The obtained model can then be used to predict EC1:5 at a certain depth from electromagnetic measurements made using the EM38 device positioned in horizontal and vertical positions at the soil surface. This exponential decay model predicted the EC1:5 well according to the results of a one-way analysis of variance, and the further comparison indicated that the modeled coefficients appeared to be slightly superior to, but not statistically different from, this exponential decay model. Nevertheless, this exponential decay model was more significant and practical because it depended on less empirical parameters and could be used to perform point predictions of EC1:5 continuously with depth.

Application of Amplitude Ratio Profiles Extracted with Prestack Kirchhoff Integral Migration

The Z component and X component profiles of seismic waves extracted with the prestack Kirchhoff integral migration could approximate to the primary wave （P wave） and converted shear wave （PS wave） profiles under certain conditions. The relative change of their reflection amplitude reflects the formation stress anomaly and subsurface media anisotropy. The principle and method for extracting amplitude ratios were studied and the application of amplitude ratio profiles was also examined when processing and interpreting actual seismic data. The amplitude ratio profile is an effective supplementary means of identifying the stratigraphic boundary and lithology.

Analytical Solutions and Computer Simulations of the Evolution of Flat Temperature Profiles in Spherical FRRPP Systems

The free-radical retrograde-precipitation (FRRPP) process was recently brought into the quantitative areas of work, based on the discovery of possibility of flat temperature profiles in spherical reactive domain systems. With an approximate decoupling analysis of the energy equation from the component-balance equations, these flat temperature profiles were found to be either stable or unstable. Moreover, resulting evolution of the flat profiles has been found to be expressed analytically through the so-called exponential Integral function, which has been shown to be quantitatively inaccurate during the early times of the process. This work tries to resolve this inaccuracy problem, by comparing the exponential integral results with polynomial approximation and numerical results. The result is that for the stable sys-tem, the linearized treatment of the evolution of flat temperature profiles is valid at the early 30% - 40% in the tem-perature axis, while the remainder of the evolution curve is well-represented by the application of the exponential integral function. For the unstable system, the only thing that can be generalized is that both linear and cubic polynomial approximations are reasonably accurate at very small times and temperatures close to initial values.

脉冲星导航试验卫星空间计时数据的初步分析

脉冲星导航试验卫星(X-ray pulsar-based navigation-1,XPNAV-1)是我国首颗致力于探索X射线脉冲星导航技术的空间试验平台,已在轨运行七年多,获得大批观测数据,本文收集了该卫星三年多的空间观测数据,开展了一些有益的技术探索.首先处理分析了卫星对Crab脉冲星观测数据,得到Crab脉冲星的每轨、每天和总脉冲轮廓,结果表明,在时间维度上脉冲轮廓是稳定的,与国内外观测结果一致性较好;其次得到Crab脉冲星不同能段脉冲轮廓,分析了脉冲轮廓随能量变化特征;在能量维度上,得到了Crab脉冲星在不同脉冲相位区间的能谱,发现能谱与相位区间的脉冲强度成正比,表明我国自主研制的聚焦型X射线探测器具备良好的技术状态,也实现了卫星精确地“看得见”脉冲星的试验目标.最后利用XPNAV-1卫星的三天观测数据,实现基于最小二乘算法的脉冲星导航试验解算,得到卫星轨道确定精度约为56.93 km,分析发现XPNAV-1星对Crab脉冲星观测误差和初始轨道误差对当前导航解算精度影响较大.

Integrative multi-omics and systems bioinformatics in translational neuroscience:A data mining perspective

Bioinformatic analysis of large and complex omics datasets has become increasingly useful in modern day biology by providing a great depth of information,with its application to neuroscience termed neuroinformatics.Data mining of omics datasets has enabled the generation of new hypotheses based on differentially regulated biological molecules associated with disease mechanisms,which can be tested experimentally for improved diagnostic and therapeutic targeting of neurodegenerative diseases.Importantly,integrating multi-omics data using a systems bioinformatics approach will advance the understanding of the layered and interactive network of biological regulation that exchanges systemic knowledge to facilitate the development of a comprehensive human brain profile.In this review,we first summarize data mining studies utilizing datasets from the individual type of omics analysis,including epigenetics/epigenomics,transcriptomics,proteomics,metabolomics,lipidomics,and spatial omics,pertaining to Alzheimer's disease,Parkinson's disease,and multiple sclerosis.We then discuss multi-omics integration approaches,including independent biological integration and unsupervised integration methods,for more intuitive and informative interpretation of the biological data obtained across different omics layers.We further assess studies that integrate multi-omics in data mining which provide convoluted biological insights and offer proof-of-concept proposition towards systems bioinformatics in the reconstruction of brain networks.Finally,we recommend a combination of high dimensional bioinformatics analysis with experimental validation to achieve translational neuroscience applications including biomarker discovery,therapeutic development,and elucidation of disease mechanisms.We conclude by providing future perspectives and opportunities in applying integrative multi-omics and systems bioinformatics to achieve precision phenotyping of neurodegenerative diseases and towards personalized medicine.

多成分脉冲轮廓模版及其在脉冲星测时中的应用

部分射电脉冲星存在模式变换现象,射电脉冲轮廓的变化给脉冲星测时工作带来了一定的困难。本文介绍了对存在多种稳定成分的脉冲轮廓进行成分分离的方案,并通过模拟数据实验说明了利用多成分脉冲标准轮廓进行测时优于使用单成分标准轮廓进行测时。

Flat soliton microcomb source

Mode-locked microcombs with flat spectral profiles provide the high signal-to-noise ratio and are in high demand for wavelength division multiplexing(WDM)-based applications,particularly in future high-capacity communication and parallel optical computing.Here,we present two solutions to generate local relatively flat spectral profiles.One microcavity with ultra-flat integrated dispersion is pumped to generate one relatively flat single soliton source spanning over 150 nm.Besides,one extraordinary soliton crystal with single vacancy demonstrates the local relatively flat microcomb lines when the inner soliton spacings are slightly irregular.Our work paves a new way for soliton-based applications owing to the relatively flat spectral characteristics.

基于ALOS DEM的乌蒙山国家级自然保护区地貌特征研究

以乌蒙山国家级自然保护区为对象,融合野外地质地貌调查和ALOS DEM数字地形分析,定量与定性相结合阐述区内地形分异、地貌格局与发育演化等特征。结果表明:1)保护区基本地貌类型以大起伏中山(57.45%)为主,其次为大起伏亚高山(30.66%)和中起伏中山(11.17%),海拔、起伏度、坡度、面积-高程积分值等定量地形指标的平均值从三江口片区至朝天马、海子坪片区逐渐降低,夷平剥蚀面级数逐渐减少;2)保护区及附近地区共发育7级夷平剥蚀面,其中Ⅰ~Ⅲ级为山顶面和残余夷平面,Ⅶ级为金沙江侵蚀阶地面,Ⅳ~Ⅵ级为剥蚀面,与区域3次构造旋回相对应;3)保护区面积-高程积分值在0.197~0.815之间,平均为0.503,超过80%的区域处于地貌演化的壮年阶段,表明区域地表侵蚀动力较强,在人类活动增强背景下存在较大的生态风险,未来的保护规划应考虑各个基本地貌类型区的地表动力差异。综合而言,独特、丰富的地貌结构使得保护区生物多样性及其所依附的生态环境要素得以保存,加强地貌多样性研究有助于从整体性和系统性的角度实现保护区资源环境管理与可持续利用。

基于先验信息动态整合的软件可靠性验证仿真

高度复杂的软件嵌入到系统时,会因为多种因素影响出现软件失效的问题,给系统造成严重破坏,为解决以上问题,提出复杂软件可靠性验证测试方法。采用运行剖面方法对复杂软件可靠性验证测试用例实施分配和选择,获取效率高的测试用例,达到提升软件可靠性验证测试有效性的目的;以此为基础开展基于先验信息动态整合的软件可靠性验证测试,依据测试结果进一步实施失效概率置信度分析,确保实现可靠性验证测试时,失效次数低于接收次数,完成最终测试。仿真结果表明,通过对该方法开展验证耗时及可靠性验证对比,表明上述方法的可信性高、有效性强。

用户画像下学术期刊智能出版的融合发展及系统构建

为探讨人工智能技术、大数据及用户画像在学术期刊智能出版转型中的应用,通过分析国内外学术期刊出版系统数字化、智能化、开放化的发展状况,提出中国学术期刊智能出版融合发展的建议。首先,探讨基于数据关联的期刊用户画像构建,分为数据采集、数据处理、标签划分、用户画像标签体系构建4个步骤;其次,提出学术期刊智能出版系统内部维度出版流程的智能化重构,包含了选题策划高效化、审稿评议智能化、编排校对自动化、生产印刷按需化、营销服务精准化;再次,加快学术期刊智能出版系统外部维度知识服务的智能化转型,包括知识检索和发现服务图谱化、知识推荐和定制服务精准化、科研决策工具智能化、多媒体服务场景化、社交媒体服务网络化、开放获取服务共享化;最后,提出全流程学术期刊智能出版系统的框架设计,为学术期刊出版智能化转型提供思路。