基于Laplace机制的普适运动传感器侧信道防御方案

针对移动设备中运动传感器侧信道的防御研究面临很多困难，已有的解决方案无法有效实现用户体验与防御能力之间的平衡，也难以覆盖各种类型的运动传感器侧信道.为了解决上述问题，系统地分析了运动传感器侧信道攻击的通用模型，针对侧信道构建过程，提出了一种基于差分隐私Laplace机制的传感器信号混淆方案.该方案实施于系统框架层，通过无差别地向传感器信号中实时注入少量受控噪声，干扰侧信道学习"用户行为-设备状态-传感器读数"之间的映射关系.构建了侧信道的通用模型，结合典型的侧信道，从理论层面详细地分析了信号混淆抵抗传感器侧信道攻击的原理，证明防御方案具有优异的普适性、可用性和灵活性，能够有效地对抗实验以外的已知或未知运动传感器侧信道攻击.最后，筛选出11种典型的运动传感器侧信道进行对抗实验，验证了该防御方案对抗实际攻击的有效性.     

Exploiting linked data to create rich human digital memories

Memories are an important aspect of a person’s life and experiences. The area of human digital memories focuses on encapsulating this phenomenon, in a digital format, over a lifetime. Through the proliferation of ubiquitous devices, both people and the surrounding environment are generating a phenomenal amount of data. With all of this disjointed information available, successfully searching it and bringing it together, to form a human digital memory, is a challenge. This is especially true when a lifetime of data is being examined. Linked Data provides an ideal, and novel, solution for overcoming this challenge, where a variety of data sources can be drawn upon to capture detailed information surrounding a given event. Memories, created in this way, contain vivid structures and varied data sources, which emerge through the semantic clustering of content and other memories. This paper presents DigMem, a platform for creating human digital memories, based on device-specific services and the user’s current environment. In this way, information is semantically structured to create temporal “memory boxes” for human experiences. A working prototype has been successfully developed, which demonstrates the approach. In order to evaluate the applicability of the system a number of experiments have been undertaken. These have been successful in creating human digital memories and illustrating how a user can be monitored in both indoor and outdoor environments. Furthermore, the user’s heartbeat information is analysed to determine his or her heart rate. This has been achieved with the development of a QRS Complex detection algorithm and heart rate calculation method. These methods process collected electrocardiography (ECG) information to discern the heart rate of the user. This information is essential in illustrating how certain situations can make the user feel.     

Multisensor based security robot system for intelligent building

Intelligent building can provide safety, convenience, efficiency and entertainment for life in the 21st century. The most importance role of the intelligent building is the security system. We develop a multi sensor-based intelligent security robot (ISR) that is widely employed in intelligent buildings. The intelligent security robot can detect abnormal and dangerous situations and notify users. The robot has the shape of cylinder and its diameter, height, and weight are 50 cm, 130 cm and 100 kg respectively. The function of the ISR contains six parts. There is the software development system; avoiding obstacle and motion planning system, image system, sensor system, remote supervise system and other systems. We develop a multi sensor-based sensor system in the ISR. We use multiple multisensor fusion algorithms to get an exact decision in the detection subsystem of the sensor system. There is an adaptive fusion method, a rule based method, and a statistical signal method. We demonstrate the remote supervisory system to control the ISR using a direct control mode and a behavior control mode. We think that the man–machine interface in a security robot system must have mobility and convenience. Therefore, we use a touch screen to display the system state, and design a general user interface (GUI) to service the user and visitors. The user can remotely control the appliance using a cell phone through a GSM modem, too. The appliance module can feedback reaction results to the user through a cell phone. Finally, we implement the fire detection system in the intelligent security robot (Chung-Cheng-I). If a fire occurs, the intelligent security robot can find out the fire source using the fire detection system. In intruder detection, we program the same scenario to detect the intruder using the intelligent security robot. The intelligent security robot transmits the message of the detection result to the user using a GSM modem for a fire event or intruder, and transmits the detection result to a client computer through the internet.     

Hollnagel’s test: being ‘in control’ of highly interdependent multi-layered networked systems

Advances in technologies for networking, sensing, and automation have resulted in multi-layered networked systems that extend information gathering, interactions across roles, and the potential for control over wider ranges. But these systems also represent a scale shift in complexity in terms of the density of interdependencies across processes and activities. In the new systems, coupling has run amok introducing new challenges about how to control processes when they are part of such highly interdependent webs. Based on the joint cognitive systems perspective, Hollnagel examines, or tests, technology changes by asking two key questions: what does it mean to be in control and how can control be amplified? Hollnagel has shown that the answers to these questions are not inherent in technology itself but rather point to emergent system properties that can and should be supported to produce success and avoid failures. This paper applies Hollnagel’s test to the reverberations of technology change that are producing multi-layered networked systems. The paper shows how being ‘in control’ of multi-layered networked systems requires the ability to navigate interdependencies and shows how ‘amplifying control’ then consists of tools that help reveal/track relevant interdependencies and help anticipate how projected actions will propagate (resonate) across interdependencies relative to goals. The end result is that a shift is underway from supervisory control to polycentric control architectures.     

STMAD: sensor-based threat’s mitigation on smartphones using allowlist and denylist

Sensors play a vital role in the smartphone for sensing-enabled mobile activities and applications. Different sources, like mobile applications and websites, access the sensors and use them for various purposes. The user needs permission to access the permission-imposed sensors. Using the generic sensor application programming interface, the user can access the no-permission-imposed sensors directly without any permission. Attackers target these sensors and make the smartphones vulnerable at the application, device and network levels. The attackers access the sensor’s information and use it for different purposes like personal identification number identification and user personal information theft. This paper presents STMAD, a novel allowlist-based intrusion prevention system to mitigate sensor-based threats on smartphones by detecting malicious access of an attacker through different channels. STMAD functions as a lightweight preventive mechanism for all sensors on the smartphone and preventing attackers from accessing sensors maliciously. The experimental results show that the proposed defense mechanism is more efficient and consumes minimal overhead. An informal security analysis also proved that the STMAD protects against various attacks.

     

Review Article A review of multi-channel indices of class separability

Abstract

An increasingly common question arising in processing digital multi-channel data from spacecraft and aircraft scanner systems is “which channels contain the best information to separate the classes of interest to the user?”. This may be to identify the best single channel for separating classes in a black and white photographic or line printer output product, or the best three channels for a colour photographic presentation of the data, or the best ‘n’ channels to enter into a classification (being mindful of the ‘trade off’ between improved sub-class separability and increasing usage of computer space and time resources). The only valid way to approach separability using more than one channel is to consider it in multi-channel space utilizing the inter-channel relationship terms. Having defined the classes using some form of hierarchical ordering approach, such as that proposed by Anderson et al. (1972), the user may compile the statistical profiles of the classes of interest from the sensor multi-channel data. Based on these statistics a number of multi-channel separability indices may be derived. Each of these indices quantifies, on the basis of the user-defined multi-channel statistics, the degree of inter-class separability the user can expect as a function of subsets of channels drawn from the overall sensor channel set. This review considers some of the more common multi-channel indices of separability and presents the links between them. Their various properties, and some limitations, are also presented as is an operational approach to their use.     

Bridging the Information Transfer Gap: Measuring Goodness of Information Fit

The ability to determine, a priori, how well an interface design meets the information needs of a user—that is, to ‘bridge the information transfer gap’—is a critical component of any intelligent interface design system. Yet most current approaches either sidestep the problem of computationally measuring ‘goodness of fit’ by compiling design knowledge into a set of pattern matching rules or, at best, use a very limited set of parameters in scoring. We describe a formal representation for capturing the information needs associated with user tasks and the information conveying capabilities of interface elements. A multifaceted scoring technique, using this representation, is presented for assessing a design's goodness of fit against current user requirements. The hallmarks of this approach are the explicit representation of the goals of good user interface design, evaluation of a proposed design against these goals and a computational approach to performing tradeoffs among these goals when incompatible. Finally, we report on the implementation and user acceptance of this design in an adaptive interface application for military attack/scout helicopters.     

Innovation as Improvisation ‘In The Shadow’

In this article, we explore processes of innovation – which are inherently uncertain – from a complexity perspective, in which they are understood as new patterns of experiences as they emerge in human conversational interaction. We reflect on local interactions between people involved in emerging processes of innovation, with a particular emphasis on the improvisational nature of interaction. Through an abductive approach, by iterating actual experiences and our understanding of them, we show that such processes are collective efforts that take place as informal, highly improvised conversations — happening ‘below the radar’ — which may unpredictably offer windows of opportunity to enable change. We show that innovation often emerges as ‘shadow themes’, experienced as subversive by those involved in the moments of interaction. While these themes are embedded in informal conversations and processes, they can be induced by invitations – conscious or unconscious moves that encourage those involved to make spontaneous moves together in a mutually improvised context. Our experience shows that the emergence of shadow themes can have a long‐term impact on the organization and the people involved, and that managers may be ‘in charge but not in control’ of such innovation processes.     

View planning for exploration via maximal C-space entropy reduction for robot mounted range sensors

We introduced the concept of C-space entropy recently as a measure of knowledge of configuration space (C-space) for sensor-based exploration and path planning for general robot–sensor systems. The robot plans the next sensing action to maximally reduce the expected C-space entropy, also called the Maximal expected Entropy Reduction (MER) criterion. The resulting view planning algorithms showed significant improvement of exploration rate over physical space-based criteria. However, this expected C-space entropy computation made two idealized assumptions: (i) that the sensor field of view (FOV) is a point and (ii) that there are no occlusion (or visibility) constraints, i.e., as if the sensor can sense through the obstacles. We extend the expected C-space entropy formulation where these two assumptions are relaxed, and consider a range sensor with non-zero volume FOV and occlusion constraints, thereby modeling a realistic range sensor. Planar simulations and experimental results on the SFU Eye-in-Hand system show that the new formulation results in further improvement in C-space exploration efficiency over the point FOV sensor-based MER formulation.     

Designing for uncertain,asymmetric control: Interaction design for brain–computer interfaces

Designing user interfaces which can cope with unconventional control properties is challenging, and conventional interface design techniques are of little help. This paper examines how interactions can be designed to explicitly take into account the uncertainty and dynamics of control inputs. In particular, the asymmetry of feedback and control channels is highlighted as a key design constraint, which is especially obvious in current non-invasive brain–computer interfaces (BCIs). Brain–computer interfaces are systems capable of decoding neural activity in real time, thereby allowing a computer application to be directly controlled by thought. BCIs, however, have totally different signal properties than most conventional interaction devices. Bandwidth is very limited and there are comparatively long and unpredictable delays. Such interfaces cannot simply be treated as unwieldy mice. In this respect they are an example of a growing field of sensor-based interfaces which have unorthodox control properties. As a concrete example, we present the text entry application “Hex-O-Spell”, controlled via motor-imagery based electroencephalography (EEG). The system utilizes the high visual display bandwidth to help compensate for the limited control signals, where the timing of the state changes encodes most of the information. We present results showing the comparatively high performance of this interface, with entry rates exceeding seven characters per minute.     

A tale of two coalitions – marginalising the users while successfully implementing an enterprise resource planning system

Classic analyses of system implementations view user participation as a key element for successful implementation. However, under some conditions, avoiding user participation offers an alternative route to a successful implementation; this is advisable especially when the user network is weak and aligning user needs with the technological capabilities will take too much resource. To illustrate such situation, we analyse how a successful implementation outcome of an enterprise resource planning (ERP) system emerged in a recently established conglomeration of two previously independent universities. The ERP was used to replace several legacy student administration systems for both political and functional reasons. It was deemed successful by both project consultants and the new university's management while the users were marginalised (‘black boxed’) and left to ‘pick up the pieces’ of an incomplete system using traditional methods such as shadow systems and work‐a‐rounds. Using a process approach and an actor–network theory ‘reading’ of related socio‐technical events, we demonstrate how three networks of actors – management, the project team and the administrative users – collided and influenced the implementation outcome and how the management and project network established the ERP as a reliable ally while at the same time the users – while being enrolled in the network – were betrayed through marginalisation. Our analysis also suggests a useful way to conduct a ‘follow the network’ analysis explaining and accounting for the observed implementation outcome. We illustrate the benefits of using a socio‐technical processual analysis and show how stable actor networks must be constructed during large‐scale information technology change and how different actor groups perceive and influence differently the implementation outcome.     

Adaptive data acquisition strategies for energy-efficient, smartphone-based, continuous processing of sensor streams

There is a growing interest in applications that utilize continuous sensing of individual activity or context, via sensors embedded or associated with personal mobile devices (e.g., smartphones). Reducing the energy overheads of sensor data acquisition and processing is essential to ensure the successful continuous operation of such applications, especially on battery-limited mobile devices. To achieve this goal, this paper presents a framework, called ACQUA, for ‘acquisition-cost’ aware continuous query processing. ACQUA replaces the current paradigm, where the data is typically streamed (pushed) from the sensors to the one or more smartphones, with a pull-based asynchronous model, where a smartphone retrieves appropriate blocks of relevant sensor data from individual sensors, as an integral part of the query evaluation process. We describe algorithms that dynamically optimize the sequence (for complex stream queries with conjunctive and disjunctive predicates) in which such sensor data streams are retrieved by the query evaluation component, based on a combination of (a) the communication cost & selectivity properties of individual sensor streams, and (b) the occurrence of the stream predicates in multiple concurrently executing queries. We also show how a transformation of a group of stream queries into a disjunctive normal form provides us with significantly greater degrees of freedom in choosing this sequence, in which individual sensor streams are retrieved and evaluated. While the algorithms can apply to a broad category of sensor-based applications, we specifically demonstrate their application to a scenario where multiple stream processing queries execute on a single smartphone, with the sensors transferring their data over an appropriate PAN technology, such as Bluetooth or IEEE 802.11. Extensive simulation experiments indicate that ACQUA’s intelligent batch-oriented data acquisition process can result in as much as 80 % reduction in the energy overhead of continuous query processing, without any loss in the fidelity of the processing logic.     

User interface based on natural interaction design for seniors

With world population ageing, how to help seniors to adapt to technology life is an important issue. Technology is becoming life rather than resistance, because many of the technology applications are often accompanied by a lot of information to process. This makes the user interface to become an important bridge between human computer interactions. Especially the inconvenience caused by human ageing, these related issues from the cognitive and operational of products are derived. This study proposes a study of user interface design based on natural interaction to increase seniors’ usage intention. In the proposed contents, the Kinect sensor is used to retrieve seniors’ in-depth information in movements, thus the user interface of system can be operated by the gesture intuitively. In the framework of the system, in the first all, the morphology is applied to identify the features of a hand from depth values obtained from the sensor. Gesture is used to recognize operating behavior of users to implement the interactive action, and collision detection is applied to confirm effectiveness of operation. On the other hand, through interpretive structural model (ISM), each design element of interactive interface can be decomposed and realized, and the solution for target and direction of design problem is also proposed. At the meanwhile, the concept of affordance is conducted to the development of interface for graphic users that proposed in this study, and the design achievement contains operation and usability of intuition can further be acquired. Finally, based on the proposed methodology, an intuitive user interface of digital devices is constructed by Java programming language that allows for verifying the feasibility of user interface for seniors. Besides, the proposed method can be widely used to develop the user interface for various products.     

A review of information systems evaluation: content,context and process

Computer-based information systems are difficult to evaluate. The difficulties are both conceptual (what should be involved in evaluation) and operational (how to carry out evaluation). Information systems evaluation is generally taken to mean the identification and quantification of the costs and benefits of an IT investment. We maintain that this approach is too narrow, and hence problematic. A broader conceptualisation is set out, which entails management of the linkages between content, context and process: the ‘what’, ‘why’ and ‘how’ of evaluation. A categorisation of the IS evaluation literature according to its emphasis on content/context/process is used to argue that effective evaluation requires a thorough understanding of the interactions between these three elements. Implications for the practice of IS evaluation are drawn out.     

Identification and characterisation of Facebook user profiles considering interaction aspects

ABSTRACT

The great number of social network users and the expansion of this kind of tool in the last years demand the storage of a great volume of information regarding user behaviour. In this article, we utilise interaction records from Facebook users and metrics from complex networks study, to identify different user behaviours using clustering techniques. We found three different user profiles regarding interactions performed in the social network: viewer, participant and content producer. Moreover, the groups we found were characterised by the C4.5 decision-tree algorithm. The 'viewer' mainly observes what happens in the network. The ‘participant’ interacts more often with the content, getting a higher value of closeness centrality. Therefore, users with a participant profile are responsible, for example, for the faster transmission of information in the virtual environment, a crucial function for the Facebook social network. We noted too that ‘content producer’ users had a greater quantity of publications in their pages, leading to a superior degree of input interactions than the other two profiles. Finally, we also verify that the profiles are not mutually exclusive, that is, the user of a profile can at determined moment perform the behaviour of another profile.     

The effects of sensory impairments on product experience and personal well-being

To determine the roles that the sensory modalities play in user product interactions, one modality was blocked during the execution of eight simple tasks. Participants reported how they experienced the products and how they felt during the experiment. Blocking vision resulted in the largest loss of functional information, increased task difficulty and task duration, and fostered dependency. On the other hand, the other senses were used more and product experiences increased in perceived intenseness. When touch was blocked, the perceived loss of information was smaller and participants reported that familiar products felt less like their own. Blocking audition resulted in communication problems and a feeling of being cut off. Blocking olfaction mainly decreased the intenseness of the experience. These outcomes suggest that vision mainly plays a functional role in everyday user-product interactions, whereas the main role for olfaction lies in the affective domain. Sensory impairments change the way people experience products. Blocking a single modality during everyday tasks gives insight into the impact of impairments. These insights can be used to develop products for multiple user groups (inclusive design) or products used under extreme environmental conditions.     

Gesture based human motion and game principles to aid understanding of science and cultural practices

We present a novel approach for recreating life-like experiences through an easy and natural gesture-based interaction. By focusing on the locations and transforming the role of the user, we are able to significantly maximise the understanding of an ancient cultural practice, behaviour or event over traditional approaches. Technology-based virtual environments that display object reconstructions, old landscapes, cultural artefacts, and scientific phenomena are coming into vogue. In traditional approaches the user is a visitor navigating through these virtual environments observing and picking objects. However, cultural practices and certain behaviours from nature are not normally made explicit and their dynamics still need to be understood. Thus, our research idea is to bring such practices to life by allowing the user to enact them. This means that user may re-live a step-by-step process to understand a practice, behaviour or event. Our solution is to enable the user to enact using gesture-based interaction with sensor-based technologies such as the versatile Kinect. This allows easier and natural ways to interact in multidimensional spaces such as museum exhibits. We use heuristic approaches and semantic models to interpret human gestures that are captured from the user’s skeletal representation. We present and evaluate three applications. For each of the three applications, we integrate these interaction metaphors with gaming elements, thereby achieving a gesture-set to enact a cultural practice, behaviour or event. User evaluation experiments revealed that our approach achieved easy and natural interaction with an overall enhanced learning experience.     

Learning from Workaround Practices: the Challenge of Enterprise System Implementations in Multinational Corporations

Based on a four‐year longitudinal case study of a French multinational corporation (MNC) this research explains how a global enterprise system, initially designed to provide greater control by headquarters across its MNC sites, led to the emergence of unexpected practices – known as workarounds – in its Chinese subsidiaries. Drawing on concepts from activity theory our findings provide greater theoretical understanding of workarounds in three ways. First, users are involved in collectively constructing and implementing workaround practices rather than simply being passive users or reduced to the dichotomous framing of ‘accepting’ or ‘rejecting’ an information system. Workarounds are not simple individual user improvizations but are collectively developed and become unofficial local rules. Second, workarounds are part of learning which goes beyond the view of workarounds as deviant and non‐compliant behavior. Third, learning activities are not restricted to users and their practices. Rather, as we demonstrate learning and evolution take place between the users, managers, processes and the system; that is, workarounds are not only a critical part of ‘getting work done’ but also an integral part of the institutionalization of an enterprise system.     

A Review of Eye Gaze in Virtual Agents,Social Robotics and HCI: Behaviour Generation,User Interaction and Perception

A person's emotions and state of mind are apparent in their face and eyes. As a Latin proverb states: ‘The face is the portrait of the mind; the eyes, its informers’. This presents a significant challenge for Computer Graphics researchers who generate artificial entities that aim to replicate the movement and appearance of the human eye, which is so important in human–human interactions. This review article provides an overview of the efforts made on tackling this demanding task. As with many topics in computer graphics, a cross‐disciplinary approach is required to fully understand the workings of the eye in the transmission of information to the user. We begin with a discussion of the movement of the eyeballs, eyelids and the head from a physiological perspective and how these movements can be modelled, rendered and animated in computer graphics applications. Furthermore, we present recent research from psychology and sociology that seeks to understand higher level behaviours, such as attention and eye gaze, during the expression of emotion or during conversation. We discuss how these findings are synthesized in computer graphics and can be utilized in the domains of Human–Robot Interaction and Human–Computer Interaction for allowing humans to interact with virtual agents and other artificial entities. We conclude with a summary of guidelines for animating the eye and head from the perspective of a character animator.     

Broadbutton Node Linking — A Generalised Approach to Hyperbase Navigation

Hypertext systems operate by establishing links within information, Links are normally established by an author, although some systems — GUIDE, for example — make little distinction between author and user, permitting deliberate modification of existing connections. However, linking between nodes, whether by original author or later user, is typically an active process. Producing effective hypertext links involves knowledge both of the system and of the particular data set within it.

I suggest that efficient link building might be greatly facilitated, and existing systems given greater functionality, if two related modifications could be made. Firstly, more general or ‘broad-button’ nodal links could be created; I use the phrase ‘broad button’ linking to describe ranked connections established between areas of a hyperbase. The term is defined in detail below. Intended to be easily selectable, broad-button links would offer users the choice of a ranked list of destinations from any point within any node. Secondly, were nodes to be ranked in order of probable user choice, allowing users a degree of feedback following selection of a node would permit such ranking to be dynamically organised. Feedback of this kind also has potential in assisting automatic establishment of appropriate new links between nodes.

In this paper I describe how such modifications might be organised, and describe some experiments which are currently being planned and undertaken to evaluate the ‘broad-button linking’ process.