Tangible geospatial modeling for collaborative solutions to invasive species management

Managing landscape-scale environmental problems, such as biological invasions, can be facilitated by integrating realistic geospatial models with user-friendly interfaces that stakeholders can use to make critical management decisions. However, gaps between scientific theory and application have typically limited opportunities for model-based knowledge to reach the stakeholders responsible for problem-solving. To address this challenge, we introduce Tangible Landscape, an open-source participatory modeling tool providing an interactive, shared arena for consensus-building and development of collaborative solutions for landscape-scale problems. Using Tangible Landscape, stakeholders gather around a geographically realistic 3D visualization and explore management scenarios with instant feedback; users direct model simulations with intuitive tangible gestures and compare alternative strategies with an output dashboard. We applied Tangible Landscape to the complex problem of managing the emerging infectious disease, sudden oak death, in California and explored its potential to generate co-learning and collaborative management strategies among actors representing stakeholders with competing management aims.     

Simplicity in cognitive assistive technology: a framework and agenda for research

Technology offers substantial benefits to the many people with some form of cognitive disability. But the power of technology often comes in a package whose complexity is a barrier to many users, leading to calls for designs, and especially designs for user interfaces, that are “simple”. This paper analyzes the idea of simplicity, and suggests (a) that simplicity in a user interface is not a unified concept, but rather has distinguishable facets, and (b) that simplicity must be defined in terms of the cognitive capabilities of a user, so that what is “simpler” for one user may be “more complex” for another. Despite (b), the prospects for universal design in this area are good, in that interface technology with the flexibility needed to produce “simple” interfaces for a range of users with different cognitive strengths will be of value in addressing the overall design space of interfaces for a broad audience. While it is possible to sketch the outlines of a useful theory of simplicity, the sketch reveals much that is not fully understood. It also reveals opportunities to rethink the architecture of user interfaces in a way that will benefit user interface development generally.     

无线认知传感器网络的研究

在无线传感器网络中引入认知无线电技术,构成无线认知传感器网络,可以减少ISM频段干扰,提高数据传输率。对无线认知传感器网络的研究目前已成为一个新的研究领域。介绍了无线认知传感器网络的概念,从无线认知传感器网络的节点、频谱感知、频谱决策、频谱共享、频谱迁移、网络层、传输层、应用层等方面综述了现有的研究成果,讨论了目前存在的问题和需要进一步研究的方向。     

A game-based approach to the teaching of object-oriented programming languages

Students often have difficulties when trying to understand the concepts of object-oriented programming (OOP). This paper presents a contribution to the teaching of OOP languages through a game-oriented approach based on the interaction with tangible user interfaces (TUIs). The use of a specific type of commercial distributed TUI (Sifteo cubes), in which several small physical devices have sensing, wireless communication and user-directed output capabilities, is applied to the teaching of the C# programming language, since the operation of these devices can be controlled by user programs written in C#. For our experiment, we selected a sample of students with a sufficient knowledge about procedural programming, which was divided into two groups: The first one had a standard introductory C# course, whereas the second one had an experimental C# course that included, in addition to the contents of the previous one, two demonstration programs that illustrated some OOP basic concepts using the TUI features. Finally, both groups completed two tests: a multiple-choice exam for evaluating the acquisition of basic OOP concepts and a C# programming exercise. The analysis of the results from the tests indicates that the group of students that attended the course including the TUI demos showed a higher interest level (i.e. they felt more motivated) during the course exposition than the one that attended the standard introductory C# course. Furthermore, the students from the experimental group achieved an overall better mark. Therefore, we can conclude that the technological contribution of Sifteo cubes – used as a distributed TUI by which OOP basic concepts are represented in a tangible and a visible way – to the teaching of the C# language has a positive influence on the learning of this language and such basic concepts.     

From turtles to Tangible Programming Bricks: explorations in physical language design

This article provides a historical overview of educational computing research at MIT from the mid-1960s to the present day, focusing on physical interfaces. It discusses some of the results of this research: electronic toys that help children develop advanced modes of thinking through free-form play. In this historical context, the article then describes and discusses the authors own research into tangible programming, culminating in the development of the Tangible Programming Bricks system—a platform for creating microworlds for children to explore computation and scientific thinking.

一种基于认知无线电的无线传感器网络邻点搜索算法

为了提高无线传感器网络中节点在多个频点工作环境下的搜索效率,提出了一种基于认知无线电技术的节点搜索算法。在分析了影响节点成功搜索的各个因素并映射这些因素到算法中相应参数的基础上,通过多种方法建立了各参数之间的联系并得出了在一定使用情况下的最优配置。算法既汲取了认知无线电中对频点利用率高、抗干扰能力强和安全性好等优点,还克服了其相对于定频通信在节点搜索能力方面的不足。     

A cube to learn: a tangible user interface for the design of a learning appliance

In this paper we introduce the design and development of the Learning Cube as a novel tangible learning appliance. Using the common shape of a cube we implemented a general learning platform that supports test based quizzes where questions and answers can be text or image based. Exploiting the physical affordances of the cube and augmenting it with embedded sensors and LCD displays placed on each face, we present different learning appliances as playful learning interfaces for children. Based on the initial observations of the experience with children, we argue that breaking conventions about how a computer has to look like, and providing children with a playful interface is a promising approach to embed and integrate technology into children’s everyday context and activities.     

DynMAC: A resistant MAC protocol to coexistence in wireless sensor networks

The growth of mobile and ubiquitous computing has increased the demand for wireless communications, which in turn raises interference levels and spectrum pollution, causing problems of network coexistence. The coexistence assurance between these devices and wireless sensor networks is a big challenge. This paper proposes a new medium access protocol, DynMAC (Dynamic MAC), which uses mechanisms of dynamic channel reconfiguration, recovery from lost links and reconfiguration of transmission parameters based on the properties of the cognitive radios, to deal with this problem. Simulations and experiments using a real WSN testbed, were performed to validate our protocol. Results show that the proposed mechanisms solve the WSN configuration problems, in noisy and interference environments, and enable the coexistence with different networks and devices operating in the same frequency spectrum, while maintaining application requirements in critical deployment scenarios.     

一种新型的认知无线电网络架构

网络宽带化、业务多样化以及现有的固定频谱管理模式使无线网络面临资源日益匮乏的巨大挑战。动态变化的异构网络环境更加剧了资源紧缺和业务需求之间的矛盾,严重制约了现有和未来无线网络的部署和运行。为解决以上难题,首先对现有无线网络协议进行了详细讨论与分析,总结出其自身特点和存在的问题,包括IEEE 802.22认知功能、IEEE 1900.4认知功能和ETSI RRS(重配置无线子系统)认知功能。在深入研究无线网络中认知理论与方法的基础上,提出一种全新的认知无线网络架构模型,包括系统频谱管理、网络规划管理、重配置管理、无线资源管理、认知环处理以及认知信息承载方式。该架构能够更好地协调和支持网络的学习、推理、预测、融合、决策和重构等行为。     

A BIPMU-based network security situation assessment method for wireless network

With the rapid development of information technology, wireless network has been accepted by the public and widely used in the daily life and work. Especially with the comprehensive deployment of 5G network technology, the application scope of wireless network is continuously increasing, which can greatly reduce the IT infrastructure overhead and human resource investment. Although the tremendous advantages, wireless network inevitably suffers from some severe security challenges. For example, the network data is characterized by large volumes, variety and high dimensions, which would greatly affect the efficiency and accuracy of network security situation assessment (NSSA). To solve this problem, we first design a novel model based on parsimonious memory unit (PMU), namely, bidirectional parsimonious memory unit (BIPMU). Compared with PMU, BIPMU can not only learn and characterize data through its time series relationship, but also comprehensively and effectively manage the potential connection of long-term and short-term dependence on time series data. Subsequently, we adopt BIPMU to design a novel NSSA method to evaluate the real-time security situation of wireless network. Finally, we develop a prototype implementation of our proposed NSSA method and provide the performance evaluation. The experimental results demonstrate that compared with the previous NSSA methods, our proposed NSSA method is much more attractive in efficiency and accuracy.     

Testbeds for ubiquitous robotics: A survey

The growing interest in ubiquitous robotics has originated in the last years the development of a high variety of testbeds. This paper presents a survey on existing ubiquitous robotics testbeds comprising networked mobile robots and networks of distributed sensors, cameras and smartphones, among others. The survey provides an insight into the testbed design, internal behavior and use, identifying trends and existing gaps and proposing guidelines for testbed developers. The level of interoperability among different ubiquitous robotics technologies is used as the main conducting criterion of the survey. Other features analyzed include testbed architectures, target experiments and usability tools.     

EEPC:一种新的无线智能传感器网络组织结构与协议

提出了一种新的基于被动聚类的网络组织结构 （Energy Efficient Protocol with Passive Clustering, EEPC）.该协议克服了原有协议性能上的缺陷,具有更好的可扩展性与容错性,实现了能源的自适应管理.     

An analytical study of central and in-network data processing for wireless sensor networks

This paper compares the performance of centralized and in-network data processing for wireless sensor networks (WSNs) under various deployment conditions on the real sensor hardware Sun SPOT from Sun Microsystems. We define several criteria to measure the quality of responses in WSN applications. Guided by an extensive experimental study, we discuss in detail the performance impacts of different deployment factors on algorithms that implement both centralized and in-network computing. Finally, performance guidelines are given to algorithm designers for WSN applications.     

一种混合轻量型无线传感器网络公钥密码方案

将基于身份的公钥机制与轻量级CA(Certificate Authority)思想相结合,构建了一个基于身份及轻量级CA混合模型的传感器网络密码方案。该方案既克服了基于身份公钥机制中的第三方密钥托管问题,又简化了基于传统证书机制中产生、验证及管理公钥的复杂性。分析表明,方案可使公钥产生轻量化,公钥验证轻量化,密钥管理无需证书,且安全性高,可抵御无线环境下易于实施的多种攻击,适用于保障资源受限的无线网络中数据的机密性、完整性和不可否认性。     

MFALM:一种水下动态传感器网络主动定位方法

针对水下动态传感器网络定位的特点及问题,提出了一种基于到达时间差(TDoA)的多频率主动定位方法MFALM(multi-frequency active localization method base on TDoA)。该方法将网络节点分为3组:信标节点、中继节点和普通节点。节点之间通过高、低两种频率分别进行近、远距离通信。为减少通信开销,定义了精简的报文格式和有效的通信方式。分析表明,该定位方法由于采用事件驱动、多频通信、精简报文,因此在定位过程中不但能够减少节点的定位开销,延长网络生存时间,而且还有定位精度高、节点密度可调等优点。     

Audio-augmented paper for therapy and educational intervention for children with autistic spectrum disorder

Autism affects children׳s learning and social development. Commonly used rehabilitative treatments are aimed at stimulating the social skills of children with autism. In this article, we present a prototype and a pilot study on an audio-augmented paper to support the therapy of children with autism spectrum disorder (ASD). The prototype supports audio recording with standard sheets of paper by using tangible tools that can be shared between the therapist and the child. The prototype is a tool for the therapist to engage the child in a storytelling activity. We use a progressive design method based on a dynamic process that merges concept generation, technology benchmarking and activity design into continuously enriching actions. The paper highlights the qualities and benefits of using tangible audio-augmented artefacts for therapy and educational intervention for children with ASD. The work describes three main qualities of our prototype: from building cooperation to attention control, flow control, and using the children׳s own voices to foster attention.     

基于RSSI的无线传感器网络定位技术的研究

节点定位技术是无线传感器网络(WSN)的支撑技术之一,给无线传感器网络的各种应用提供节点的位置信息,具有重要的作用。本文分析了无线传感器网络的节点定位算法的原理和分类,并着重分析了基于信号强度测距法(RSSI)的无线定位技术,提出了将信号强度理论值与经验值相融合的定位方法。     

基于能量指纹匹配的无线认知网络仿冒主用户攻击检测

频谱感知是无线认知网络有效工作的基础,现有研究主要集中在提高频谱检测的效率,对于如何保证在不可信的网络环境中实现安全可靠的频谱感知还没有理想的解决方案。针对频谱感知过程中存在的一种典型攻击行为一仿冒主用户攻击,提出了一种基于能量指纹匹配的检测方案。认知用户利用自身的位置分布特征,使用能量检测生成主用户的能量指纹,以此作为节点的身份标识,分析不同用户对频谱资源的使用方式,最终实现对仿冒行为的检测。理论分析以及模拟测试表明,该方案在误检概率较低的前提下,可以有效地检测仿冒攻击行为,提高频谱感知的准确率。     

基于无线传感网络的大体积混凝土裂缝监控技术

对大体积混凝土浇灌过程中的温度和温度应力进行监测与控制,可以有效防止裂缝的产生。在分析了大体积混凝土温度和应力常见监测方法的特点后,提出一种基于无线传感网络和移动agent技术的分布式温度和应力监控系统。系统利用无线传感器节点采集混凝土温度和应力等信号,实现并行的分布式信息采集与处理,安装布置简便;将移动agent应用于无线传感网络以解决异构系统间协作、协调及信息融合,有效降低了冗余数据的传输及节点能耗。详细分析了系统结构组成及设计方法,并利用该系统进行了现场测试,实验结果表明,该系统能够较好实现对混凝土施工过程中的温度、应变情况进行实时在线监测。