基于串口通信的PTB220气压传感器误差自动调整系统设计

为进一步提升自动气象站计量检定工作的自动化水平,简化气压传感器示值超差调整工作,通过对PTB220气压传感器工作原理的分析与研究,利用省级气象计量检定业务系统(3MS)的部分硬件,采用串口通信自动应答技术,在原有3MS系统自动化检定的基础上实现了PTB220气压传感器数字量及模拟量示值超差的自动调整。文中详细阐述了数字量及模拟量调整的原理及操作流程,给出了串口通信参数配置及自动调整软件部分代码示例,并通过实际业务验证了系统设计思路的可行性。     

在VB6．0中利用通信控件通过Modem拨号实现远程通信的原理与方法

本对如何在VB6．0中利用Mscomm32.ocx通信控件通过Modem拨号实现远程通信的原理与方法进行了论述。     

基于Linux系统的串口服务器设计与实现

1引言随着气象观测业务的快速发展,越来越多的气象设备投入到业务中,设备之间的互联要求变得越来越高。在各种传感器中,以RS-232、RS485、RS422为代表的串行通信方式因其易于实现和维护,得到广泛应用。观测到的气象数据从业务台站发送到省级或者国家级中心站,需要在业务台站安装应用软件,通过应用软件将数据发送到省级或者国家级中心站。现有气象业务体制改革,很多业务台站观测场与值班室分离,不方便安装应用软件,串行通信方式逐渐暴露出其传输距离近、网络化实现复杂的缺点。     

CAWS600-B型自动气象站的串口连接与保护

在分析RS232C标准和光电隔离器件的基础上,给出了CAWS600-B自动气象站技术手册未能详尽提供的串口连接图,为台站维护CAWS600-B自动气象站及光电隔离器用于防雷工程提供了参考。     

气象部门"GRPA++财务处理系统"功能实现与应用

2010年气象部门开始使用"GRPA++财务处理系统".系统主要包括财务人员在线建立账套、账务日常业务处理和填报电子报表及上报,主管单位在线远程查询其下级单位某个会计期间或某几个连续会计期间各会计科目本期借/贷方发生额及期末余额、并对总分类账用于统计汇总某单位某个会计期间或某几个连续会计期间内各会计科目的总账情况."G...     

基于VB通信控制技术的气象短信服务

气象短信业务是GSM运营商与气象部门合作开展的面向群体和公众的一种服务。文中介绍了如何利用Visual Basic 6.0通信技术,实现PC机与GSM模块之间的通信,开展气象决策短信服务。主要对短信编辑、短信发送、系统管理和一些关键技术作了较为详细的阐述,可为其他地市级气象局设计出有自己特色的气象决策短信服务平台系统提供技术借鉴和参考。该系统设计过程中强化信息的发布权威,对外发布的内容必须经过审阅和签名,对用户号码实行授权管理等。     

基于TMS320VC5402的RS_485通信设计

完成了基于TMS320VC5402 DSP的RS_485通信的硬件设计和软件编程.基于美国TI公司TMS320VC5402 DSP芯片的多通道缓冲口(McBSP)进行适当的硬件扩展,以SPI方式直接和MAXIM公司的MAX3100通用异步串行收发器接口,然后经Linear Technology公司的LTC1480超低功耗RS_485收发器,从而实现了一种新的基于RS_485标准接口串行通讯的数据传输,充分利用了DSP的片上资源,使硬件和软件结构尽量简单化.     

基于MICAPS系统数据接口的0℃和-20℃层高度计算方法

多普勒雷达冰雹指标的识别为预报员在短时临近预报中的冰雹警报、预警信息的发布提供了可靠依据,多普勒雷达冰雹指标的识别是雷达RPG基于0℃和-20℃层高度得出的,这样每天0℃和-20℃高度的输入就是必需的。本文介绍基于MICAPS数据接口,使用VC＋＋6．0语言编写程序自动计算0℃和-20℃层高度的一种近似计算方法,完全可以满足日常业务使用需要。     

区域自动气象站双卡备份通信技术的实现与应用

通过对区域自动气象站无线传输双卡通讯模块试制,再通过通信软件技术,实现通信模块双卡自动备份并自适应4G、3G和2G信号,解决因单个通讯运营商基站故障导致的传输不通畅问题;提高区域自动气象站传输及时率。     

用TURBO BASIC实现国际二号码的异步串行通信

着重介绍了国际二号码与ASCII码相互转换及用TURBOBASIC实现异步串行通信时的一些关键技术的解决办法。     

移动互联网环境下终端与服务器安全交互的研究

移动互联网的飞跃式发展与智能终端成本的降低,惠及了众多的普通消费者,移动互联时代用户的隐私与信息安全变得更为重要.针对WiFi热点环境下用户隐私与数据容易泄露的环节,对比传统的常用加密算法与使用效果,提出了一种基于OAuth 协议的令牌机制的安全交互方式,它可以在保证用户相关隐私与信息安全的同时,保证服务器的响应速度,且在用户的应用存在风险或异常时,可及时提醒并引导用户进行相关安全操作.压力测试结果表明该设计是有效可行的.     

Chemical ionisation mass spectrometer for measurements of OH and Peroxy radical concentrations in moderately polluted atmospheres

A new version of an atmospheric pressure chemical ionisation mass spectrometer has been developed for ground based in situ atmospheric measurements of OH and total peroxy (HO₂ + organic peroxy) radicals. Based on the previously developed principle of chemical conversion of OH radicals to H₂SO₄ in reaction with SO₂ and detection of H₂SO₄ using an ion molecule reaction with NO₃^─, the new instrument is equipped with a turbulent chemical conversion reactor allowing for measurements in moderately polluted atmosphere at NO concentrations up to several ppb. Unlike other similar devices, where the primary NO₃^─ ions are produced using radioactive ion sources, the new instrument is equipped with a specially developed corona discharge ion source. According to laboratory measurements, the overall accuracy and detection limits are estimated to be, respectively, 25% and 2 × 10⁵ molecule cm^-3 for OH and 30% and 1 × 10⁵ molecule cm^-3 for HO₂ at 10 min integration times. The detection limit for measurements of OH radicals under polluted conditions is 5 × 10⁵ molecules cm^-3 at 10 min integration times. Examples of ambient air measurements during a field campaign near Paris in July 2007 are presented demonstrating the capability of the new instrument, although with reduced performance due to the employment of non isotopic SO₂.     

A novel high-resolution small ion spectrometer to study ion nucleation of aerosols in ambient indoor and outdoor air

An electrically based ion spectrometer is described, capable of measuring particle sizes and mobilities from molecular ions (small ions) to aerosol particles across a size range of 0.4 to 30 nm in diameter. It consists of a single cylindrical capacitor divided into three electrically insulated sections. The current arriving at the central section is measured by an electrometer and represents the ion flux over a known range of mobilities determined by the applied voltage. The applied voltage is scanned in steps to measure the ion fluxes over a large number of overlapping mobility ranges. The recorded signal and the response function of the instrument are unfolded using a maximum entropy procedure to give a high-resolution measured mobility spectrum. The maximum entropy approach offers a considerable improvement over traditional aspiration collectors and can approach the resolution of a drift tube system. In this way, the spectrometer successfully overcomes the diffusion limit to small ion resolution. Illustrative spectra are shown, demonstrating for the first time the presence of some resolved structure within the small ion spectrum at the highest mobilities. It is demonstrated that the actual mobility spectrum of small ions falls in the range 0.8–2.0 × 10⁻⁴ m² V⁻¹ s⁻¹. This represents a narrower range than that previously measured which is attributed to improved spectral resolution in the present work.     

无线温湿度采集管理系统

设计了一种无线传输温湿度采集管理系统.该系统采用数字式温湿度传感器进行温湿度数据采集,通过无线传输模块连接微处理器,微处理器使用串口与 PC 机进行通信,并通过软件编程将采集的数据存放到数据库进行数据管理、备份、存储、查询以及分析处理.     

基于北斗卫星的预警信息发布技术研究及实现

利用北斗卫星短报文通信功能,以广播方式发布预警信息,可提高预警信息的覆盖范围和时效性, 填补我国海洋及陆地边远地区预警信息发布空白。但北斗卫星预警信息发布存在传输速率低、冗余信息量大、长预警信息发布成功率低的问题。该文对北斗卫星预警信息发布系统的系统结构、协议体系和关键问题开展研究,通过指挥机并联、预警信息编码、影响区域识别、联合补包等方法,解决了北斗卫星预警信息发布系统建设的关键问题。在此基础上,该文设计了预警信息网络发布协议、预警信息北斗发布协议和预警信息北斗传输协议,并开发了原型系统。     

激光雨滴谱仪与自动气象站观测雨量对比分析

介绍了LNM激光雨滴谱仪的构成及原理,对由激光雨滴谱仪和自动气象站同步观测所获取的雨量资料进行对比分析,并结合新一代多普勒雷达基数据提供的反射率因子与雨量作对比分析。结果表明,两种仪器探测到的雨强随时间变化趋势较为一致,但变化幅度差异大,激光雨滴谱仪探测到的雨强最大值远大于自动气象站测得的最大值且出现时间要提早些;两种仪器观测到的雨量资料与观测点处雷达反射率因子的对比表明,激光雨滴谱仪探测到的雨量与雷达反射率因子有更好的一致性。     

基于NTP的网络对时系统设计与实现

在气象信息网络系统内,由于网络传输的延迟以及Internet传输的不安全性,导致时间的准确性难以保证,严重影响了气象报文传输的及时性和有效性。为了解决这一问题,基于NTP协议,采用client/server方式实现了系统内计算机和外部精确时钟源的主动对时,保证了系统内时间的准确性和一致性。     

基于流程控制的国际气象通信数据收集管理系统的设计与实现

近年来,天气和气候业务对国外数据种类和时效要求不断提高,为解决大量数据的收集分发压力以及管理问题,设计并实现了基于流程控制的国际气象通信数据收集管理系统。系统应用数据收集器Logstash、Inotify监听机制与分析平台Kibana等技术,支持多种通信协议,扩展Scrapy网络爬虫功能,通过流程控制、任务调度等方式实现大量数据快速高效收集和集成管理,有效提高数据并行处理能力和可扩展性,且设计了全流程监视,保障数据时效。系统已经上线提供服务,为业务/科研用户提供全球观测数据、国外卫星数据和数值预报产品等300余种,日收集数据量约2 TB。     

Drivers and dimensions of flood risk perceptions: Revealing an implicit selection bias and lessons for communication policies

Flood damages have increased in many regions around the world, and they are expected to continue to rise in the future due to climate change. To reverse this trend, awareness of flood risk among the population is required to support flood risk management policies and improve flood preparedness. However, empirical studies on the drivers of flood risk perceptions conducted thus far have reported mixed and contradictory results. The aim of this study is to provide insights into the factors that influence perceptions of various dimensions of flood risk to draw lessons to guide flood risk communication strategies. We test a variety of hypotheses of possible factors of influence on flood risk perceptions that are motivated by theoretical concepts and previous empirical studies, whilst also controlling for socio-demographic variables. A representative sample of 2,976 residents answered our survey assessing the role that past flood experiences and risk communication play in shaping flood risk perceptions. Besides exploring flood risk perceptions more robustly, this large sample also facilitates the systematic study of ‘don’t know’ answers, which are often dismissed as missing data in many studies. Rather in this study we analyze what ‘don’t know’ answers reflect in terms of knowledge about particular dimensions of flood risk. The study finds that older people, as well as those who have higher levels of income and education, are significantly more likely to express their flood risk perceptions, respondents who are unable to answer the questions on flood risk perceptions face a lower flood risk, report to have been living in their neighbourhood for a shorter period of time and have less first-hand flood experience. Previous studies might thus be biased by an implicit selection effect. Finally, we show that findings are highly dependent on other explicit choices made by researchers, including the apparently self-fulfilling impact of selecting one explanatory framework over another. New insights emerge from the role that information campaigns and social vulnerability play in the ability to answer the questions. Based on our findings, we offer recommendations for improving flood risk communication policies, specifically increasing the frequency of communication, ensuring that campaigns are focused in terms of the content they provide and the subgroups of the population they target.