运载火箭测发控技术未来发展与展望

工业电子、测试、测控、仪表、大数据、云平台等技术的发展,为运载火箭测发控技术的发展提供了先进的技术途径;运载火箭箭上电气系统一体化设计,火箭快速测发、健康管理、子级独立测试、异地远程测试发射支持等需求,给测发控系统研制及更新换代提出更高的要求;通过对运载火箭地面测控系统供配电、有线测控、无线测控、数传通信、测发控软件5个组成部分的演变及发展方向进行了论证分析,并提出了后续测发控系统技术发展的规划路线;同时结合未来运载火箭的发展需求和目前测发控系统现状提出了测发控系统后续发展的可实施途径;最后提出顶层规范技术路径;从型号牵引转变为装备化研制;规范型谱产品研制、箭上地面同步发展的测发控系统设计新思路;为未来运载火箭测发控系统研制提供方向。     

基于数字孪生的火箭测试与发射过程健康管理技术研究

为了解决运载火箭对地面测试与发射过程中对数据综合分析能力,飞行过程的故障诊断和预测能力,以及故障处理措施的快速决策等能力的迫切需求,提出一种基于数字孪生技术的火箭测试与发射过程健康管理系统设计方案;该方案通过建立运载火箭测试与发射阶段数字孪生模型,实现对火箭测试和发射过程的天地镜像仿真,依托数字孪生模型,对运载火箭健康管理功能进行了设计和优化;利用真实火箭和数字孪生火箭的信息交互,可有效实现火箭测试过程数据分析、飞行过程协同诊断,以及故障处理决策支持等功能;该系统提高了火箭发射的可靠性,为火箭可靠飞行提供了技术保障;同时,该技术在运载火箭健康管理上的应用也面临一些关键技术还需要进一步突破和发展.     

BIT技术在运载火箭测试系统中的研究与应用

对BIT技术在运载火箭测试发射控制系统测试领域中的应用进行了研究。从BIT技术的设计原则、设计原理和工作模式等方面进行分析,设计了BIT测试流程并将其应用在运载火箭测试系统中,利用大数据降低了BIT系统虚警率,对于运载火箭测试领域提高测试可靠性,提高故障检测、故障隔离及排除效率对于火箭测发过程具有重要意义。     

防空导弹发控装置测试诊断系统设计

研制一套针对某型防空导弹地面发控装置的通用测试设备,用于部队防空导弹维修线,实现对防空导弹地面发控装置的自动化检测和诊断,达到降低维修成本．节约经费,提高部队维修效率和作战能力的目的;系统采用了基于VXI总线技术的测控仪器组合,实现了对防空导弹发控装置内部所有信号的仿真和测试,通过对被测对象的详细测试需求分析．针对防空导弹发控装置不同单元的测试特点来编制各自的测试与诊断流程,实现了测试和故障诊断一体化的要求。     

面向火箭数据分析和故障诊断的数据仓库设计

针对运载火箭测试发射数据分散存储且数据利用不充分的问题,提出了以数据仓库技术对火箭的测试发射数据进行组织和存储管理,实现对火箭数据价值的深层次发掘。根据运载火箭数据的特点,提出了数据仓库基础层、源数据层、数据交互层、数据架构层、应用层、显示层六个层次的框架设计;通过面向火箭数据分析和故障诊断的数据清洗规则设计,对不同来源、不同格式的数据进行清洗和加载;对火箭的数据应用方向进行了探索,设计了包络分析、相关性分析、故障诊断等数据分析模块。用某型号火箭测试发射数据进行了验证,结果表明,数据仓库方案切实可行,为后续火箭数据的持续性管理和分析奠定了基础。     

适用于新型运载火箭的快速测试发射技术研究

运载火箭测试发射系统对数据处理能力、数据通信能力的要求越来越高,提高发射效率、缩短测试时间、优化测试流程是航天发射任务长期的需求;为了适应新型运载火箭快速测试发射的需求,提高我国地面测试发射系统整体水平,在借鉴和继承国内外成熟型号地面测试发控系统优秀设计思想的基础上,概要介绍了新型运载火箭测发控网络的特点,提出了一种适用于新型运载火箭地面测试发射系统框架和快速测试发射工艺流程,给出了最少发射条件的建议,为新型运载火箭机动快速发射测试方法和测试流程的制定提供了参考依据。     

运载火箭一体化综合测控技术研究

新一代运载火箭对测发控系统的自动化、智能化,以及未来产品化的测试数据管理和批量并行测试需求提出了更高的要求,本文以运载火箭地面测控一体化及信息综合管理系统为背景,对火箭的组件、部段级批量并行测试及整箭测发控技术进行了研究,提出了分布式实时综合测控技术,将动力、测量、控制等多个分系统以及部段测试统一到本系统中,对系统数据传输的实时性和可靠性进行了研究。搭建了基于上述新型测发模式的联动试验系统,包括前端分布式节点系统、后端统一测发系统及远端云服务支持管理系统等,对一体化综合测控技术进行了验证。     

机载设备测试性建模与应用

测试性模型是进行测试性仿真、设计、分析、评估的基础和关键。该文描述了设备测试性建模方法与测试性建模流程,为实现对复杂系统的测试性分析及故障诊断,获取有指导意义的诊断策略服务实际应用。测试性设计中采用多信号流建模技术,分层次建立某型机载音频设备的测试性模型;对设备故障模式、故障影响的分析归纳,收集各层级设备故障模式样本形成FMEA分析表;运用计算机建模仿真工具辅助,构建了定量化的测试性模型;通过模型仿真获得被测设备故障检测率、隔离率以及相关故障诊断流程;经测试性指标对比分析及测试性试验验证,发现该测试性模型中薄弱环节,经过迭代模型、改进测试性方案后,显著提高了设备的测试性指标,满足设备的应用使用需求。     

基于国产网络设备的火箭地面测发控网络平台设计

高可靠的测试网络作为运载火箭远距离测发控的基础平台,是实现运载火箭地面远距离测试发控的重要技术保障;通过对运载火箭地面测发控网络架构深入研究,采用国产商用网络设备搭建原型平台、开展原理性验证试验,经过反复试验,不断改进技术方案,解决了冗余热备网络协议选用、冗余故障切换、故障切换实时性、网络可靠性等技术难题,提出了基于国产化设备的网络架构设计方案;对网络架构的工作原理、可靠性、实时性、安全性进行了详细分析;建立的国产化高可靠网络架构,不仅能够应对复杂的火箭测试现场,使网络平台具有更好的可靠性、实时性、扩展性和灵活性,更进一步提高了网络的安全性;设计的国产化网络平台架构可用于运载火箭地面测发控网络使用。     

运载火箭一体化测发系统的并行测试研究

现役运载火箭一体化测发系统的单任务测试模式,已无法满足运载火箭的高密度、快速测发的需求。通过控制软件多线程设计实现多任务控制的并行处理;使用分布式执行终端,同步完成并行测试功能。设计具有包含多任务信息的通讯协议,实现并行测试信息的网络传输。利用软件的共享缓存技术实现多任务之间的信息交互。在信息传输中通过字节流模式进行先进先出的实时通信,保证了运载火箭测发的实时性。通过对一体化测发系统的并行测试研究,可实现一套测发控系统对箭上多个子系统同时进行测试。 并行测试技术的研究利用了计算机系统并行处理能力,通过测发软件的并行设计,实现可由用户控制的多任务并行测试系统,提高了运载火箭的测试效率和节省测试费用,是解决运载火箭高密度、低成本发射的一种技术途径。     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

Enhancing a leaf radiative transfer model to estimate concentrations and in vivo specific absorption coefficients of total carotenoids and chlorophylls a and b from single-needle reflectance and transmittance

The relative concentrations of different pigments within a leaf have significant physiological and spectral consequences. Photosynthesis, light use efficiency, mass and energy exchange, and stress response are dependent on relationships among an ensemble of pigments. This ensemble also determines the visible characteristics of a leaf, which can be measured remotely and used to quantify leaf biochemistry and structure. But current remote sensing approaches are limited in their ability to resolve individual pigments. This paper focuses on the incorporation of three pigments—chlorophyll a, chlorophyll b, and total carotenoids—into the LIBERTY leaf radiative transfer model to better understand relationships between leaf biochemical, biophysical, and spectral properties.Pinus ponderosa and Pinus jeffreyi needles were collected from three sites in the California Sierra Nevada. Hemispheric single-leaf visible reflectance and transmittance and concentrations of chlorophylls a and b and total carotenoids of fresh needles were measured. These data were input to the enhanced LIBERTY model to estimate optical and biochemical properties of pine needles. The enhanced model successfully estimated reflectance (RMSE = 0.0255, BIAS = 0.00477, RMS%E = 16.7%), had variable success estimating transmittance (RMSE = 0.0442, BIAS = 0.0294, RMS%E = 181%), and generated very good estimates of carotenoid concentrations (RMSE = 2.48 µg/cm², BIAS = 0.143 µg/cm², RMS%E = 20.4%), good estimates of chlorophyll a concentrations (RMSE = 10.7 µg/cm², BIAS = − 0.992 µg/cm², RMS%E = 21.1%), and fair estimates of chlorophyll b concentrations (RMSE = 7.49 µg/cm², BIAS = − 2.12 µg/cm², RMS%E = 43.7%). Overall root mean squared errors of reflectance, transmittance, and pigment concentration estimates were lower for the three-pigment model than for the single-pigment model. The algorithm to estimate three in vivo specific absorption coefficients is robust, although estimated values are distorted by inconsistencies in model biophysics. The capacity to invert the model from single-leaf reflectance and transmittance was added to the model so it could be coupled with vegetation canopy models to estimate canopy biochemistry from remotely sensed data.     

Mr. Twinn’s bombes

This article discusses the history and design of the special versions of the bombe key-finding machines used by Britain’s Government Code & Cypher School (GC&CS) during World War II to attack the Enigma traffic of the Abwehr (the German military intelligence service). These special bombes were based on the design of their more numerous counterparts used against the traffic of the German armed services, but differed from them in important ways that highlight the adaptability of the British bombe design, and the power and flexibility of the diagonal board. Also discussed are the changes in the Abwehr indicating system that drove the development of these machines, the ingenious ways in which they were used, and some related developments involving the bombes used by the U.S. Navy’s cryptanalytic unit (OP-20-G).