Taking technology to the field: hardware challenges in developing countries

A great deal has been written about the various socio-political, economic, and cultural reasons that information and communications technologies (ICTs) fail to achieve the potential they represent. Far less attention has been paid to the technology itself, and the role that the hardware plays in the success or failure of ICT4D. Along these lines, we find a disconnect between much of the scholarly ICT4D research and many of the needs and concerns of practitioners and intended beneficiaries. Using interviews and surveys, this article asks ICT4D practitioners and end-users about the technology and hardware needs and challenges they face in the field. These practitioners consistently suggest that electricity is the most important hardware-related concern, followed closely by cost, robustness/ruggedness, and ease of maintenance/repair. We argue for the inclusion of hardware and technology considerations in the planning and implementation of ICT4D projects. Failure to address these concerns may account for the underperformance of many technologies in the development context.     

The challenges of technology research for developing regions

The work we've done in the world's developing regions has been immensely rewarding and helped make us all strong advocates for technology. The first reward is simply the experience of these countries, their surprising happiness, and the technology insights that come from being there. The deeper reward is of course actually helping people by creating new options through technology. However, we encountered a wide range of technical, environmental, and cultural challenges that are outside the scope of typical computer science research. In this article, we share some of our experiences with the hope of increasing understanding of these issues. We also hope to help others, particularly researchers from outside these regions, to avoid our mistakes. We document real challenges, try to generalize them, and suggest steps that might at least mitigate the problems.     

基于DSP控制的能量再生回馈电网研究

利用电力电子技术中的整流、逆变，以及与能量回馈相关的信号反馈控制、数字信号处理（DSP）等控制技术，通过跟踪捕获电网电源信号，将伺服电机在运行过程中快速制动和频繁正反转时所产生的再生能量以SPWM波的形式．转变为与电网电源信号同步的电能信号。同时滤除再生电能SPWM渡中的谐波干扰成分，提高功率因数，将再生能量反馈回电网，予以优化回收。     

Applying a socially inspired technique (tags) to improve cooperation in P2P networks

In this paper, we focus on the problem of maintaining significant levels of cooperation in peer-to-peer (P2P) networks of selfish adaptive peers. We propose a simple algorithm that maintains high levels of cooperation in such a network while performing the collective task of file sharing. The algorithm is adapted from novel "tag" models of cooperation that do not rely on explicit reciprocity, reputation or trust mechanisms. A sequence of three simulation models is presented-starting with an abstract model of tag-based cooperation (TagWorld) and finishing with a P2P file-sharing model (FileWorld) that puts the technique to work. From analysis of extensive computer simulations, we demonstrate the technique to be scalable, robust, and decentralized; it requires no central servers or authorities. The algorithm is relatively simple: peers do not need to store additional trust information about other nodes or to perform significant additional processing.     

Socially inspired search and ranking in mobile social networking: concepts and challenges

In this paper, we provide an overview of challenges in mobile search and ranking, and envision the fundamental features that should be satisfied. We argue that two principles will help improve the relevance and quality of mobile search and ranking: the first one is to examine both intrinsic content features and context of items (usage statistics and social features, etc.); and the second one lies in that no algorithms can replace the objectivity of a human being—let users define the sites that they feel are relevant, leverage their social networks, and over time see their results become highly personalized. Specifically, wireless-virtualcommunity-based mobile search and ranking architecture is proposed in this paper, in which communities act as a first class abstraction for information sharing. Then, we introduce briefly the potential procedures of achieving high relevance and quality in mobile search and ranking based on wireless virtual community.     

Socially inspired search and ranking in mobile social networking: concepts and challenges

In this paper, we provide an overview of challenges in mobile search and ranking, and envision the fundamental features that should be satisfied. We argue that two principles will help improve the relevance and quality of mobile search and ranking: the first one is to examine both intrinsic content features and context of items (usage statistics and social features, etc.); and the second one lies in that no algorithms can replace the objectivity of a human being—let users define the sites that they feel are relevant, leverage their social networks, and over time see their results become highly personalized. Specifically, wireless-virtualcommunity- based mobile search and ranking architecture is proposed in this paper, in which communities act as a first class abstraction for information sharing. Then, we introduce briefly the potential procedures of achieving high relevance and quality in mobile search and ranking based on wireless virtual community.     

Prompting,feedback and error correction in the design of a scenario machine

A scenario machine limits the user to a single action path through system functions and procedures. Four scenario machines were designed to embody different approaches to prompting, feedback, and automatic error correction for a “learning-by-doing” training simulator for a commercial, menu-based word processor. Compared with users trained directly on the commercial system, scenario machine users demonstrated an overall advantage in the “getting started” stage of learning. Initial training on a “prompting + automatic correction” system was particularly efficient, encouraging a DWIM (or “do what I mean”) approach to training system design. Curiously, training on a “prompting + feedback” system led to relatively impaired performance on a set of transfer of learning tasks. It was suggested that too much training information support may obscure the task coherence of the action scenario itself relative to a design that provides less explicit direction.     

Lump localisation through a deformation-based tactile feedback system using a biologically inspired finger sensor

The ability to localise harder areas in soft tissues is often desired during robot-assisted surgical operations. A deformation-based tactile feedback system was tested for the detection of objects within soft tissues, after being chosen over common pressure-based designs. This system uses a biologically inspired sensor that offers a new finger-like approach to tactile sensing. A tactile shape display developed from previous successful designs was used to output the sensed tactile information. Using the tactile feedback system on a mechanical teleoperated device, test subjects palpated a number of artificial tissue models to locate objects of varying stiffness. The addition of the tactile feedback system improved the detection of the objects from 64% to 98%, reduced the localisation error from 18 to 11 mm, and also decreased the time the users spent palpating the tissue from 55 to 37 s. This demonstrates that a deformation-based tactile feedback system can be used to successfully locate hard embedded objects within soft tissue, with a significant improvement over force and visual feedback alone. During testing, it was found that the users were able to more accurately locate the softest embedded objects compared to stiffer ones. Reasons for this observation are discussed.     

A biologically inspired active compliant joint using local positive velocity feedback (LPVF).

Starting from studies which revealed that positive feedback is found in the control system for walking in arthropods, we have constructed a new positive feedback driven joint that can be used for solving compliant motion tasks. We propose two different joint constructions each of which shows passive compliance. Based on these joints we introduce three different local positive velocity feedback (LPVF) controllers and discuss their properties in the context of motion generation in closed kinematic chains. The third circuit named undelayed dLPVF is used for the control of a compliant planar manipulator which turns a crank. Our concept is of highly decentralized nature and follows the idea of embodiment. In our case this means that a process which is controlled by LPVF controllers reveals its nature when the controllers interact with this process.     

Successes and challenges in developing a hybrid approach to sentiment analysis

This article covers some success and learning experiences attained during the developing of a hybrid approach to Sentiment Analysis (SA) based on a Sentiment Lexicon, Semantic Rules, Negation Handling, Ambiguity Management and Linguistic Variables. The proposed hybrid method is presented and applied to two selected datasets: Movie Review and Sentiment Twitter datasets. The achieved results are compared against those obtained when Naïve Bayes (NB) and Maximum Entropy (ME) supervised machine learning classification methods are used for the same datasets. The proposed hybrid system attained higher accuracy and precision scores than NB and ME, which shows its superiority when applied to the SA problem at the sentence level. Finally, an alternative strategy to calculating the orientation polarity and polarity intensity in one step instead of the two steps method used in the hybrid approach is explored. The analysis of the yielded mixed results achieved with this alternative approach shows its potential as an aid in the computation of semantic orientations and produced some lessons learnt in developing a more effective mechanism to calculating the orientation polarity and polarity intensity.     

Coping with information technology challenges to identity: A theoretical framework

Drawing on ideas from identity control theory and coping theory and on a diverse range of social psychology literature, we propose an integrative theoretical framework that unpacks and traces the processes by which information technology comes to affect users’ identity. We define four types of strategies (acting on the situation, adjusting the self, cathartic practices and distancing) through which people cope with technological challenges to the self. We suggest that these strategies may lead to four individual-level outcomes, namely reinforced identity, redefined identity, ambivalent identity and anti-identity. The model is provided with a preliminary support through reference to real life situations, carefully selected from extant empirical IS enquiries.     

微弱能量收集电路技术的研究现状与发展趋势

随着物联网的发展和无线传感器网络的广泛使用,以电池为主的供能方式弊端日渐显露,微弱能量收集因其诸多优点而得到了极大重视.介绍了目前微弱能量收集电路技术研究的现状,对目前的微弱能量收集电路技术进行了分析,阐述了多种微弱能量的收集,介绍了目前高效率的微弱能量收集电路的设计模式.结合目前微弱能量收集电路的优缺点,展望了能量收集电路技术未来的研究趋势和方向.     

Information technology in developing countries: A need for theory building∗

Abstract

The use of information technology (IT) in developing countries has attracted a considerable amount of attention in recent years. However, the research in this area is largely fragmented, and there is a need to consolidate efforts in order to make research more effective. Theory can provide a basis for this consolidation process by allowing communication between different researchers and also between researchers and practitioners. The primary objective of this paper is to describe aspects of the state of existing theory in the field of IT in developing countries, and discuss possible research directions for the future. A total of 199 articles were analyzed to describe existing research themes, and future directions are discussed in terms of level of analysis, research methods, and research reports.     

Driving simulation: challenges for VR technology

Virtual driving environments represent a challenging test for virtual reality technology. We present an overview of our work on the problems of scenario and scene modeling for virtual environments (VEs) in the context of the Iowa Driving Simulator (IDS). The requirements of driving simulation-a deterministic real-time software system that integrates components for user interaction, simulation, and scenario and scene modeling-make it a valuable proving ground for VE technologies. The goal of our research is not simply to improve driving simulation, but to develop technology that benefits a wide variety of VE applications. For example, our work on authoring high-fidelity VE databases and on directable scenarios populated with believable agents also targets applications involving interaction with simulated, walking humans and training in the operation of complex machinery. This work has benefited greatly from the experience of developing components for a full-scale operational VE system like IDS, and we believe that many other proposed VE technologies would similarly benefit from such real-world testing     

Integrative connectionist learning systems inspired by nature: current models, future trends and challenges

The so far developed and widely utilized connectionist systems (artificial neural networks) are mainly based on a single brain-like connectionist principle of information processing, where learning and information exchange occur in the connections. This paper extends this paradigm of connectionist systems to a new trend—integrative connectionist learning systems (ICOS) that integrate in their structure and learning algorithms principles from different hierarchical levels of information processing in the brain, including neuronal-, genetic-, quantum. Spiking neural networks (SNN) are used as a basic connectionist learning model which is further extended with other information learning principles to create different ICOS. For example, evolving SNN for multitask learning are presented and illustrated on a case study of person authentification based on multimodal auditory and visual information. Integrative gene-SNN are presented, where gene interactions are included in the functioning of a spiking neuron. They are applied on a case study of computational neurogenetic modeling. Integrative quantum-SNN are introduced with a quantum Hebbian learning, where input features as well as information spikes are represented by quantum bits that result in exponentially faster feature selection and model learning. ICOS can be used to solve more efficiently challenging biological and engineering problems when fast adaptive learning systems are needed to incrementally learn in a large dimensional space. They can also help to better understand complex information processes in the brain especially how information processes at different information levels interact. Open questions, challenges and directions for further research are presented.     

Knowledge management and the semantic Web: from scenario to technology

This article describes a new vision of the semantic Web as a knowledge management environment introduces new requirements, including the ability to semiautomatically learn ontologies and extract metadata. The article's general tenor, and particularly their scenario demonstrating how the semantic Web might be used, was directed toward identifying and using services on the Web. The pursuit of this vision continues.     

Perceived playfulness,gender differences and technology acceptance model in a blended learning scenario

The importance of technology for education is increasing year-by-year at all educational levels and particularly for Universities. This paper reexamines one important determinant of technology acceptance and use, such as perceived playfulness in the context of a blended learning setting and reveals existing gender differences. After a literature review on the mentioned topics, some statistical analysis, such as difference between means and structural equation modeling, were run with a sample of 484 students. The main contribution of this study is to provide evidence that there exist gender differences in the effect of playfulness in the student attitude toward a technology and the intention to use it. In females, playfulness has a direct influence on attitude toward using the system. In males, this influence is mediated by perceived usefulness. Some implications and conclusions are included.     

A noncausal framework for model-based feedback control of spatially developing perturbations in boundary-layer flow systems. Part II: numerical simulations using state feedback

We present numerical results illustrating the successful state feedback control of a spatially developing boundary-layer flow system. Control is applied using the noncausal framework developed in Part I of this study. After addressing some important regularization issues related to the proper treatment of the infinite-dimensional nature and semi-infinite spatial extent of the present system, we compute the state-feedback control gains according to the equations developed in Part I at several spanwise wavenumbers β. We then inverse transform the result to obtain spatial convolution kernels for determining the control feedback. The effectiveness of the controls computed using these feedback kernels, which are well resolved on the computational grid and spatially localized in the spanwise direction, is tested using direct numerical simulation of the boundary-layer flow system. A significant damping of the flow perturbation is observed, which is of the same order as the damping that arises when applying significantly more expensive iterative adjoint-based control optimization schemes.     

The sound of the underwater dolphin-kick: developing real-time audio feedback in swimming

One of the main factors for improving movement execution and motor performance in competitive sports is the availability of useful feedback. While coaches can communicate verbally with athletes in most sports, swimming is different. Because the swimmer is underwater most of the time, any type of real-time feedback is difficult. Since the presentation of acoustic information through sonification has proven beneficial to certain motor skills, this paper describes initial considerations for an application of interactive sonification as real-time audio feedback to provide useful information to improve motor execution in swimming. Special attention is given to the underwater dolphin-kick (UDK), which is performed by athletes after every start and every turn and is one of the critical factors for overall performance in world-class swimming. It was examined whether the characteristics of the UDK are represented in the sound in order to create congruency between sound, action and reaction.Two different sonification models were designed using data from 11 national athletes (six juniors, aged 17.0 ± 1.5 years and five seniors aged 23.6 ± 1.3 years). The sonified data were presented to sport scientists and coaches and tested in in a pilot study with three club-level swimmers (17.0 ± 0.8 years) in swimming training. The results indicate that the athletes became aware of relevant aspects of the movement with both sonification models, to which they had no access so far. In detail, the sonification provided information on forward propulsion, movement rhythm and kick frequency – all factors contributing to overall motor performance. Individual statements showed that the athletes noticed deceleration phases in the forward propulsion and the time duration in the movement execution and tried to adapt their movements accordingly. The approaches presented here could therefore serve as a useful training tool for swimmers to improve their UDK.