基于低功耗的蔬菜大棚环境监控系统的设计

为了帮助偏远落后地区实现蔬菜大棚增产增收,采用超低功耗MSP430F单片机作为控制器,设计了一种基于低功耗蔬菜大棚环境监控系统。首先介绍了监控系统的功能和结构框图,随后阐述了其硬件和软件的设计与实现。实验证明,本系统对蔬菜大棚内的温度、湿度、CO2浓度、光照等环境因素能进行很好的监测与控制,且具有简单、低功耗、低成本、高可靠性、易于实现和维护、可用电池供电等诸多优点,具有很好地推广及应用前景。     

基于STM32处理器的蔬菜大棚监测终端设计与实现

设计和实现一个基于STM32处理器的蔬菜大棚监测终端系统。该系统具备实时监测蔬菜大棚环境参数的功能,并通过通信模块将数据上传至云服务器。通过硬件设计、软件开发及数据处理和通信配置,建立了一个完整的监测系统。这个系统有望提高农户对蔬菜大棚的管理效率,促进农业生产的发展。     

蔬菜大棚的智能化管理系统

为了提高农村蔬菜大棚的科技含量,介绍了蔬菜大棚的智能化管理系统,本系统主要应用单片机实监测和控制棚内的温湿度、光照强度等参数,并将数据通过RS-485总线传输到上位PC机进行分析、管理及距离测控,构成多个蔬菜大棚的综合监控网络。本系统功能强,成本低,具有很高的实用价值。     

基于3G和ZigBee的蔬菜大棚远程无线监控系统的设计

设计一套智能蔬菜大棚远程无线实时监控系统。该系统由监控终端节点、网关节点和监控中心组成。监控终端采用以CC2533为核心的ZigBee模块,构建ZigBee星型结构的无线传感网,实现蔬菜大棚中的环境数据智能化采集;网关节点以ARM10微处理器PXA270和Linux操作系统为核心进行开发,使用ZigBee通信实现数据的汇聚和3G无线通信技术实现数据的远程传输。该系统不仅满足了数据采集和数据传输的安全和性能要求,而且很好地解决了传统的蔬菜大棚系统的布线麻烦、节点不易移动和系统维护复杂等问题,满足了智能蔬菜大棚中环境参数监测的需要。     

温室大棚温度控制系统的设计

主要介绍一种基于STC89C52单片机的温室蔬菜大棚温度检测与控制系统。系统以STC89C52单片机为基础,利用DS18B20温度传感器实现对温室大棚温度的测量,利用模糊控制算法实现对温度的控制。实验证明,该系统具有性价比高,使用寿命长,智能化程度高等优点,具有一定的实用价值。     

基于单片机的蔬菜大棚温湿度监控系统设计

针对传统大棚温湿度监控系统存在监控数据误差大的问题,笔者设计了以单片机作为控制核心的蔬菜大棚温湿度控制系统,包括单片机控制模块、温度传感器模块和湿度传感器模块,并从硬件和软件两方面介绍了单片机温度控制系统的设计思想,对硬件原理图和程序流程图进行了系统描述。实验表明,基于单片机的蔬菜大棚温湿度监控系统具有更高的准确性。     

智能蔬菜大棚环境远程监控系统设计

利用现代科学技术实现蔬菜大棚的自动化生产,可解决传统蔬菜大棚中存在检测精度不高、测控不及时等问题。采用模块化设计理念,分析了蔬菜大棚中温湿度及光照强度等因素,设计了以STC89C51单片机为控制核心的蔬菜大棚环境监控系统。通过DHT11温湿度传感器及光敏电阻实现温湿度及光照参数检测,可通过按键电路对参数上下限阈值进行调节。采用继电器作为控制输出模块对加除湿装置、升降温装置等设备进行控制。由光敏电阻及AD转换芯片组成的光照强度检测模块实现了对大棚卷帘开关的控制。采用Proteus对系统进行了软件仿真与调试,并制作完成了远程监控系统。结果表明,经调试该系统实现了对温湿度及光照强度检测与远程控制功能,实现了预期目标。     

智慧农业技术在蔬菜大棚设计中的应用

本文在介绍智慧农业和相关技术的基础上,重点介绍了智慧农业技术在蔬菜大棚中的具体应用.蔬菜大棚的智慧构建贯穿了蔬菜种植的生产、加工、流通以及消费的整个链条环节.并重点介绍了智慧蔬菜大棚建设中生产监控、安全监控、产品溯源、移动执法和电商平台的具体设计.     

基于蔬菜大棚的模糊温度控制器的设计

大棚蔬菜突破了季节的限制,能够在一年四季提供各种新鲜蔬菜,但温度的剧烈变化往往影响蔬菜的生长。针对蔬菜大棚复杂的温度环境,基于模糊控制理论,设计了一种模糊温度控制器,它通过对模糊信息的处理,实现对大棚的恒温控制,文中详细介绍了基于单片机的模糊温度控制器的硬件和软件设计。     

深度学习在多时相大棚提取应用研究

蔬菜大棚对于农业生产具有重要意义。受季节和环境影响,其在遥感影像上不同时期呈现不同形态,仅通过单时相特征提取精度不能满足要求。近几年,深度学习被证明适合遥感数据的分类,为实现深度学习在农业遥感上的有效应用,提出了一种改进的多时相语义分割模型（Multi-temporal Spatial Segmentation Network,MSSN）用于蔬菜大棚提取。提出基于补丁长短时记忆网络（Patch-LSTM）,该网络充分利用图像的空间和时序信息。采用带空洞卷积的空间金字塔池化（ASSP）解决网络对尺度敏感问题。进一步添加跳连层（Skip-layer）和反卷积层提升特征图的还原能力。选择山东高密GF-2遥感影像进行实验。结果表明,该分割模型在测试集上有0.95的Precision、0.92的F1 score以及0.93的前景IoU（Intersection Over Union）,可以实现高精度的蔬菜大棚提取,为深度学习在农业遥感的应用提供新的方法。     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.