单模-多模光纤产生系列Bottle beam

提出一种利用多模光纤的多模干涉效应在自由空间中获得多个局域空心光(Bottle beam)的新方法。单模-多模光纤结构是一段多模光纤无偏心地连接到一段单模光纤上,光由单模光纤传输到多模光纤激发产生一系列的LP0,n模,由于多模干涉效应在多模光纤中相互叠加,当入射到自由空间后形成了多个Bottle beam。文中对光束传输过程进行理论分析并利用Matlab进行仿真实验,结果表明在自由空间中可以获得系列Bottle beam。当多模光纤纤芯直径分别为45μm,60μm和90μm时所选择的光场段内的Bottle beam的尺寸大小基本相同(约400μm×20μm),而第一个空间暗域沿轴向两侧相对光强差值分别为0.62,0.41和0.11,可见当多模光纤的纤芯直径越大时所得到的Bottle beam暗域的轴向两侧光强越相近,因此也越有利于囚禁微粒。

Simulation Model of Mechanical Properties of Point - Bonded Nonwovens

A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical properties of fibers, the arrangement of bond points in the fibrous web and specimen size are inputted into the computer. Relaxation method and relevant algorithms of computer simulation are described in detail. The validity of the model is also demonstrated.

GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——

By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points.

Coupled Fixed Point for (<i>&alpha;</i>, <i>&Psi;</i>)-Contractive in Partially Ordered Metric Spaces Using Compatible Mappings

In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result.

Epidemio-Clinical, Therapeutic and Evolutive Aspects of Pulmonary Embolism in Young Subject in the Cardiology Department in Point “G” Hospital University Center Bamako

Objective: The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of the University Hospital Center (CHU) Point G in Bamako-Mali. Methodology: This was an analytical study from January 01, 2018 to December 31, 2018 in the CHU Point G cardiology department, including all patients hospitalized during this period. Results: Of 1379 hospitalized patients, 19 patients were concerned by pulmonary embolism of the young person. The prevalence of pulmonary embolism of the young person was 1.37%. The most affected age group was 21 - 30 (47.4%) of patients. The predominance was female (89.47%) with a gender ratio of 0.11 in favour of women. The average age in the series was 29.79 years with extremes of 16 years and 40 years. Factors predisposing to pulmonary embolism were dominated by peri partum, cardiomyopathy and obesity with 47.3%, 31.57% and 21.1%, respectively. The dominant signs were chest pain and dyspnea in 94.7% and 89.5% of cases respectively. Pulmonary embolism was unlikely in 60.52% according to the Geneva and Wells score simplified. At the thoracic angioscanner, the embolism was bilateral in 52.6% of cases and distal in 36.8% of patients;in 10 patients who performed cardiac ultrasound, pulmonary arterial hypertension (70%), dilation of the right ventricle (20%) and left ventricular dilation (40%). Hyper leucocytosis (47.4%), anemia and low prothrombin rate (TP) (22.2%) were the most found biological abnormalities. More than 2/3 (68.5%) our patients had an intermediate mortality risk according to the PESI (Pulmonary Embolism Severity Index) score. The average hospital stay was 10 days. Hospital mortality was 10.5%. Conclusion: The pulmonary embolism of the young person is a frequent, serious and multifactorial pathology and the female sex is most affected especially during peri partum periods, hence the need for preventive measures. Clinical signs are not specific and based on the assessment of clinical probability. Pulmonary angioscanner remains the confirmation review in our context.

Cross-Correlation Detection of Point Sources in the WMAP First Year Data

We apply a Cross-Correlation （CC） method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources.

CAS 132-2006 Standard for Flat Panel Display TV Set Installation Service Formulating and Enforcing Main Point Explanation and Analysis

CAS 132-2006 formulation background and work courses Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower and lower. Flat panel display TV sets have begun entering the mainstream and are now the first choice of some consumers when making new TV purchases.Display TV Set Installation Service Point Explanation and AnalysisRepair, Retreat and Change Duty Stipulations. Peculiar use conditions, usage environments, and the practical circumstances of user consumption service requirements, etc., were also taken into account on the basis of extensive investigation, testing, and verification.……

用于温度传感器原位在线校准的水三相点自动复现控制系统

温度传感器在长时间温度测量中会出现性能漂移导致测量误差,为现场实时校准温度传感器实现长期稳定的高精度测量,需要基于国际温标ITS-90规定的温度固定点,对传感器进行无人自主原位校准。水三相点是水、冰、气三相平衡共存的温度点,其温度为国际温标中的0.01℃固定点,是对传感器进行校准的最常用的固定温度点。水三相点瓶是再现水三相点的关键装置。相较于传统的玻璃外壳水三相点瓶,金属外壳的水三相点瓶更为耐用,更适用于自动原位校准。为了实现水三相点的自动浮现,根据高纯水自发相变原理,设计了一种基于半导体帕尔贴效应快速稳定复现水三相点的自动控制系统及其控制方法。利用热电制冷器(TEC)和温度控制器为金属水三相点瓶提供过冷环境,在基于模型的制冷调度算法控制下,实现了较长时间保持稳定的水三相点状态。实验室测试表明,该控制系统可以在150 min内达到0.01℃的温坪,并保持稳定的三相点温度20 min及温度波动度±1 mK。温度原位在线自动校准系统可以为深海、深空及偏远地区的高精度温度测量提供校准服务。

A new calibration model for pointing a radio telescope that considers nonlinear errors in the azimuth axis

A new calibration model of a radio telescope that includes pointing error is presented, which considers nonlinear errors in the azimuth axis. For a large radio telescope, in particular for a telescope with a turntable, it is difficult to correct pointing errors using a traditional linear calibration model, because errors produced by the wheel-on-rail or center bearing structures are generally nonlinear. Fourier expansion is made for the oblique error and parameters describing the inclination direction along the azimuth axis based on the linear calibration model, and a new calibration model for pointing is derived. The new pointing model is applied to the 40 m radio telescope administered by Yunnan Observatories, which is a telescope that uses a turntable. The results show that this model can significantly reduce the residual systematic errors due to nonlinearity in the azimuth axis compared with the linear model.

Study on the method of optimal location on explosion events at near-source site

IntroductionEarthquake location is one of the inverse problems in seismology. The accurate earthquake source location is the basis of studies of earthquake images, the relation analysis between seismicity and tectonics, and the important parameters of earthquakes. It is also the basic data used to study the space distribution of aftershocks after a strong earthquake. The earthquake location accuracy mainly depends on reliability of the velocity models for the earth￠s crust, the reasonable design of the seismograph network, the accuracy of arrival time, and the location method used (ZHAO, 1983; ZHU, ZHAO, 1997; LI, et al, 1999). The reliability of the velocity model directly influences loca-tion results. The reasonable seismograph network design can improve the location accuracy; otherwise it will in-troduce ill-conditioned equations and large location error. If arrival time is not accurate, for example, if the seismic phase is wrongly identified or the time service is inaccurate, large arrival time error will be produced, and the location results and real hypocenters will be discordant. Different location algorithms adopted will produce differ-ent location errors. The residual criterion chosen has influence on location results. Besides, whether the event is correctly associated also influences the location quality. In practice, it can often be seen that large location devia-tion introduced by wrong event association.

Exploiting Virtual Elasticity of Production Systems for Respecting OTD-Part 1: Post-Optimality Conditions for Ergodic Order Arrivals in Fixed Capacity Regimes

Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arrivals, may compromise the observance of on-time supplies for some orders. The purpose of this paper is to evaluate the conditions of post-optimality for stochastic order rate governed production systems in order to observe OTD. Instead of a heuristic or a simulative exploration, a Cartesian-based approach is applied to developing the necessary and sufficient mathematical condition to solve the problem statement. The research result demonstrates that increasing speed of throughput reveals a latent capacity, which allows arrival orders above capacity limits to be backlog-buffered and rescheduled for OTD, exploiting the virtual manufacturing elasticity inherent to all production systems to increase OTD reliability of non JIT-based production systems.

A New Thioamide Derivative for Separation and Preconcentration of Multi Elements in Aquatic Environment by Cloud Point Extraction

2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results.

Observation of a diverse deviation from macropore-formation theory in silicon electrochemistry

Via anodizing patterned and unpatterned samples with a high HF concentration （[HF]）, the degree of deviation from pore-formation theory was found to be markedly different. Based on the analysis of scanning electron microscope （SEM） micrographs and current-voltage （I - V） curves, the variation of physical and chemical parameters of patterned and unpatterned substrates was found to be crucial to the understanding of the observations. Our results indicate that the initial surface morphology of samples can have a considerable influence upon pore formation. The electric-field effect as well as current-burst-model was employed to interpret the underlying mechanism.

Fixed Point Theorems of the Iterated Function Systems

In this paper, we present some fixed point theorems of iterated function systems consisting of α-ψ-contractive type mappings in Fractal space constituted by the compact subset of metric space and iterated function systems consisting of Banach contractive mappings in Fractal space constituted by the compact subset of generalized metric space, which is Mso extensively applied in topological dynamic system.

Population Spatial Distribution Based on Luojia 1-01 Nighttime Light Image:A Case Study of Beijing

With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban development.By mastering the refined population spatial distribution in administrative units,the quantity and agglomeration of population distribution can be estimated and visualized.It will provide a basis for a more rational urban planning.This paper takes Beijing as the research area and uses a new Luojia1-01 nighttime light image with high resolution,land use type data,Points of Interest(POI)data,and other data to construct the population spatial index system,establishing the index weight based on the principal component analysis.The comprehensive weight value of population distribution in the study area was then used to calculate the street population distribution of Beijing in 2018.Then the population spatial distribution was visualize using GIS technology.After accuracy assessments by comparing the result with the WorldPop data,the accuracy has reached 0.74.The proposed method was validated as a qualified method to generate population spatial maps.By contrast of local areas,Luojia 1-01 data is more suitable for population distribution estimation than the NPP/VIIRS(Net Primary Productivity/Visible infrared Imaging Radiometer)nighttime light data.More geospatial big data and mathematical models can be combined to create more accurate population maps in the future.

A New Critical Value Concerning the Genealogy of Long Period Families at L_4 in the Restricted Three-body Problem

We found another critical mass ratio value -↑μ between μ4 and μ5 concerning the genealogy of the long period family around the equilateral equilibrium point L4 in the restricted three-body problem. This value has not been pointed out before. We used numerical computations to show how the long period family evolves around this critical value. The case is similar to that of the critical values between μ2 and μ4, with slight difference in evolution details.

基于FAST算法的呼吸机湿化瓶异物检测技术

当采用传统的方法对呼吸机湿化瓶进行异物检测时,经常会出现判断错误的情况,为了解决这一问题,文中提出一种基于FAST的新算法对湿化瓶图像进行处理。首先对图像进行加速分割测试,对图像的特征点进行提取后挑选出优秀的特征点,然后通过采样得到特征点周围的信息,进而得到相应图像的二进制描述子,最后对相邻两帧的图像进行匹配得到其位移偏差。通过对算法进行仿真测试发现,该方法可有效降低湿化瓶图像中的位移偏差,具有较高的匹配准确率,对呼吸机湿化瓶异物检测及报警机制的构建具有一定应用价值。

带内螺纹的饮水瓶盖注射模设计

对饮水瓶盖的结构进行了分析,采用1模2腔三板模成型塑件,塑件上的内螺纹采用由液压缸、齿条、齿轮、螺纹、型芯组成的机构脱模,脱模时通过齿条和齿轮驱动内螺纹型芯旋转,内螺纹型芯一边旋转一边后退进行脱模。模具经批量生产验证:模具脱模机构运行稳定,成型的塑件合格率高,内螺纹没有损坏。

揭示中国5000年前酿造谷芽酒的配方

通过对西安米家崖遗址陶器上淀粉粒、植硅体、以及化学残留物的综合分析,本研究揭示了迄今为止中国最早的酿造谷芽酒的直接证据。结果显示,米家崖酿酒的原料包括黍、大麦、薏米、以及一些块根作物,说明在距今约5000年的仰韶文化晚期,中原地区已经发展出了较为成熟的谷芽酒酿造技术。同时,这项研究也对大麦传入中国初期的功能提出一种全新的见解。我们认为,酿酒可能是最初促使大麦从欧亚大陆西部传入中原的动因。

逆向工程技术及应用

逆向工程技术历经数十年的研究与发展,已经成为产品快速开发过程中重要支撑技术.介绍了逆向工程的基本概念、国内外的发展现状及趋势,并通过牛奶瓶逆向实例分析对数据获取、数据预处理、曲面重构等关键技术进行较详尽的阐述.