Kun Mean Hou | ISIMA (original) (raw)

Papers by Kun Mean Hou

Sensors

For the next coming years, metaverse, digital twin and autonomous vehicle applications are the le... more For the next coming years, metaverse, digital twin and autonomous vehicle applications are the leading technologies for many complex applications hitherto inaccessible such as health and life sciences, smart home, smart agriculture, smart city, smart car and logistics, Industry 4.0, entertainment (video game) and social media applications, due to recent tremendous developments in process modeling, supercomputing, cloud data analytics (deep learning, etc.), communication network and AIoT/IIoT/IoT technologies. AIoT/IIoT/IoT is a crucial research field because it provides the essential data to fuel metaverse, digital twin, real-time Industry 4.0 and autonomous vehicle applications. However, the science of AIoT is inherently multidisciplinary, and therefore, it is difficult for readers to understand its evolution and impacts. Our main contribution in this article is to analyze and highlight the trends and challenges of the AIoT technology ecosystem including core hardware (MCU, MEMS/NE...

IEEE Transactions on Reliability

To adapt to the uncertain environment smartly and timely, cyber physical systems (CPSs) have to i... more To adapt to the uncertain environment smartly and timely, cyber physical systems (CPSs) have to interact with the physical world in a decentralized but rigorous, organized way. Guaranteeing the timing reliability is key to achieve consensus on the order of distributed events, as well as dependable cooperative decision processing. Based on our hierarchically decentralized compositional self-adaptive framework, we propose a formal compositional reliability-contract-based solution to guarantee the timing reliability of event observation and decision processing in a large-scale, geographically distributed CPS. As the prophetic decision may not fit the local situation well because of the uncertainties, we propose a gradual contract optimization solution to refine the dependability, timeliness, and energy consumption. Following the seven proposed composition schemes, we employ the nondominated sorting genetic algorithm II (NSGA-II) algorithm to optimize arrangement of decision. Moreover, a topology-aware time reserving solution is applied to improve the resilience of processing time and to tolerance timing failures. Both simulation results and real-world testing are introduced to evaluate the efficacy of our proposal. We believe that the formal compositional contract will be a competitive CPS solution to analyze requirements and optimize the self-adaptation decision at runtime.

Cyber Physical Systems (CPS) has been a popular research area in the last decade. The dependabili... more Cyber Physical Systems (CPS) has been a popular research area in the last decade. The dependability of CPS is still a critical issue, and rare survey has been published in this domain. CPS is a dynamic complex system, which involves various multidisciplinary technologies. To avoid human error and to simplify management, self-management CPS (SCPS) is a wise choice. And to achieve dependable self-management, systematic solution is necessary to verify the design and to guarantee the safety of self-adaptation decision, as well as to maintain the health of SCPS. This survey first recalls the concepts of dependability, and proposes a generic environment-in-loop processing flow of self-management CPS, and then analyzes the error sources and challenges of self-management through the formal feedback flow. Focus on reducing the complexity, we first survey the self-adaptive architecture approaches and applied dependability means; then we introduce a hybrid multi-role self-adaptive architecture...

Managing the Internet of Things: Architectures, Theories and Applications, 2000

Sensors, 2016

The worldwide economic cost of road crashes and injuries is estimated to be US$518 billion per ye... more The worldwide economic cost of road crashes and injuries is estimated to be US$518 billion per year and the annual congestion cost in France is estimated to be €5.9 billion. Vehicular Ad hoc Networks (VANETs) are one solution to improve transport features such as traffic safety, traffic jam and infotainment on wheels, where a great number of event-driven messages need to be disseminated in a timely way in a region of interest. In comparison with traditional wireless networks, VANETs have to consider the highly dynamic network topology and lossy links due to node mobility. Inter-Vehicle Communication (IVC) protocols are the keystone of VANETs. According to our survey, most of the proposed IVC protocols focus on either highway or urban scenarios, but not on both. Furthermore, too few protocols, considering both scenarios, can achieve high performance. In this paper, an infrastructure-less Traffic Adaptive data Dissemination (TrAD) protocol which takes into account road traffic and network traffic status for both highway and urban scenarios will be presented. TrAD has double broadcast suppression techniques and is designed to adapt efficiently to the irregular road topology. The performance of the TrAD protocol was evaluated quantitatively by means of realistic simulations taking into account different real road maps, traffic routes and vehicular densities. The obtained simulation results show that TrAD is more efficient in terms of packet delivery ratio, number of transmissions and delay in comparison with the performance of three well-known reference protocols. Moreover, TrAD can also tolerate a reasonable degree of GPS drift and still achieve efficient data dissemination.

Opodis, 1998

ABSTRACT We present a new and simple topology named HCN, which is well adapted to distributed sha... more ABSTRACT We present a new and simple topology named HCN, which is well adapted to distributed shared MIMD. The HCN may be modelled by a regular oriented symmetric graph, where each node corresponds to the vertex and the connection corresponds to the arc. The HCN has a fixed degree (Δ=c) where c also defines the number of nodes in a SMIMD cluster. The graph order is c n , where n is the hierarchical level and each node is identified by nlog 2 c bit. The HCN is partitionable and recursive, its diameter is D n =2D n-1 +1. A connection function is defined permitting to implement efficiently the routing algorithm. The collective communication of HCN such as broadcasting will be compared with the well know topology hypercube. The HCN is well adapted for a large field of application and it may be built easily by using of-the-shelf processor (ADSP-2106X SHARC...).

DREAM is a super small distributed hard real-time micro-kernel based on LINDA concept. The key fe... more DREAM is a super small distributed hard real-time micro-kernel based on LINDA concept. The key features of DREAM are: pseudo process and tuple migration, DSP hardware tuning and ease fault-tolerant applications implementation by using different approaches such as PB, DMR, TMR. In this paper, we present the basic concepts of DREAM that allow pseudo process and tuple migration. A case study of fault -tolerance (P/B approach) is implemented on TMS320C31 starter&#x27;s kits. Keys word: Super small distributed hard real-time micro-kernel, Fault-tolerance, Dynamic reconfiguration, LINDA, Pseudo process and tuple migration.

Sensors (Basel, Switzerland), Jan 10, 2015

In recent years, IoT (Internet of Things) technologies have seen great advances, particularly, th... more In recent years, IoT (Internet of Things) technologies have seen great advances, particularly, the IPv6 Routing Protocol for Low-power and Lossy Networks (RPL), which provides a powerful and flexible routing framework that can be applied in a variety of application scenarios. In this context, as an important role of IoT, Wireless Sensor Networks (WSNs) can utilize RPL to design efficient routing protocols for a specific application to increase the ubiquity of networks with resource-constrained WSN nodes that are low-cost and easy to deploy. In this article, our work starts with the description of Agricultural Low-power and Lossy Networks (A-LLNs) complying with the LLN framework, and to clarify the requirements of this application-oriented routing solution. After a brief review of existing optimization techniques for RPL, our contribution is dedicated to a Scalable Context-Aware Objective Function (SCAOF) that can adapt RPL to the environmental monitoring of A-LLNs, through combinin...

Les dernières avancées technologiques dans le domaine des capteurs et des réseaux sans fil sont c... more Les dernières avancées technologiques dans le domaine des capteurs et des réseaux sans fil sont capitales pour la surveillance et la gestion d'environnement pour soutenir le développement durable. L'évolution des technologies telles que les circuits intégrés, les communications sans fil, permettent aujourd'hui une intégration avancée des techniques de contrôle environnemental. Les réseaux de capteurs sans fil se sont développés dans un premier temps grâce aux applications militaires, mais ils peuvent maintenant se démocratiser aux applications environnementales. Le domaine des réseaux de capteurs sans fil est en expansion, mais les plateformes actuelles ne répondent pas entièrement à toutes les contraintes imposées par les nouvelles applications agri-environnementales. Le développement d'un module appelé LiveNode a été effectué pour permettre le déploiement de tel réseau. Un autre objectif est de diminuer le coût de ces réseaux en utilisant des composants électroniqu...

The Wireless Sensor Networks (WSN) with their constant evolution, need new management methods to ... more The Wireless Sensor Networks (WSN) with their constant evolution, need new management methods to be monitored efficiently by taking into account their constraints such as energy consumption, reliability and remote monitoring. Note that WSN has diverse application domains: smart home, smart care, environmental data collection etc. In order to manage a large scale WSN, some Wireless sensor network Management Tools (WMTs) are developed. Some of them use SNMP protocol but it is impossible to implement the full classical SNMP standard on each node. Therefore, it is important to develop a new WMT with a restricted SNMP standard dedicated to WSN applications. In this paper, we present a new WMT named LiveNCM: LiveNode Non invasive Context-aware, and modular Management tool. LiveNCM is divided into two main parts: one is centralized on the fixed network structure and another one, distributed on each node. Each part introduces the concept of non-invasive context aware to reduce data exchange...

2011 IEEE 7th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2011

Wireless sensor networks (WSNs) will play a significant role in precision agriculture to support ... more Wireless sensor networks (WSNs) will play a significant role in precision agriculture to support sustainable development. Since it's a more economic and practical solution to deploy reprogrammable sensor nodes than non-reprogrammable ones, sensor node reprogramming technique becomes a key issue. Currently, the challenge of sensor node reprogramming mainly results from the resource constraint and diverse platforms in WSNs. In our work, we firstly ported a small footprint Java Virtual Machine simpleRTJ to wireless sensor nodes based on AT91SAM7S256 microcontroller for a reprogramming task. This method not only facilitates the application development but also shows its advantage in heterogeneous environments. However, the high memory resource requirement of simpleRTJ makes it inappropriate for some ultra low power 8-bit microcontrollers, such as ATMEGA1281, which has particularly constrained resource. Thus we propose a new efficient and portable reprogramming method (EPRM) by using pre-linked native code to reduce memory footprint and by the way to reduce energy consumption. To validate this new approach, EPRM is implemented on two platforms (32-bit and 8-bit cores) and its efficiency in terms of resource consumption (memory and energy) is evaluated by comparing with simpleRTJ ones. The obtained results show that EPRM is well adapted to high resource-constraint wireless sensor nodes.

2011 International Conference on Wireless Communications and Signal Processing (WCSP), 2011

Nowadays to diagnose cardiac arrhythmias Holter device is used to record 1 or 2 ECG leads during ... more Nowadays to diagnose cardiac arrhythmias Holter device is used to record 1 or 2 ECG leads during 24 or 48h. Power consumption limitations determine that the amount of data needs to be diminished without damaging the quality of information. To get a solution, we introduce a novel method based on Compressed Sensing (CS) technique to the Wearable ECG sensor (WES). The main principle underlying this framework is to sample analog signals at sub-Nyquist rate at the analog-digital converters (ADCs) and to classify directly compressed measurement into normal and abnormal state. Those compressed measurements which imply a risk of cardiac anomaly will be stored in a multimedia flash memory card or be transferred to the terminal of the network for a cardiologist to make an off-line diagnosis of cardiac arrhythmias using the reconstructed signals from the compressed measurements. In this paper we propose a scheme to directly classify compressed ECG samples into normal or abnormal states, thus avoiding reconstruction of the entire signal to perform this task. Our algorithm takes advantage of estimating parameters directly from the compressed measurements; thereby eliminating the reconstruct stage and reducing the computational complexity in WES. Direct cardiac arrhythmia detection based on CS reduces 34% energy consumption and 90% storage in WES for the reconstructed performance of 41dB.

Wireless Sensor Network, 2009

Recent developments of the wireless sensor network will revolutionize the way of remote monitorin... more Recent developments of the wireless sensor network will revolutionize the way of remote monitoring in different domains such as smart home and smart care, particularly remote cardiac care. Thus, it is challenging to propose an energy efficient technique for automatic ECG diagnosis (AED) to be embedded into the wireless sensor. Due to the high resource requirements, classical AED methods are unsuitable for pervasive cardiac care (PCC) applications. This paper proposes an embedded real-time AED algorithm dedicated to PCC systems. This AED algorithm consists of a QRS detector and a rhythm classifier. The QRS detector adopts the linear time-domain statistical and syntactic analysis method and the geometric feature extraction modeling technique. The rhythm classifier employs the self-learning expert system and the confidence interval method. Currently, this AED algorithm has been implemented and evaluated on the PCC system for 30 patients in the Gabriel Monpied hospital (CHRU of Clermont-Ferrand, France) and the MIT-BIH cardiac arrhythmias database. The overall results show that this energy efficient algorithm provides the same performance as the classical ones.

International Journal of Computer Applications, 2012

The IEEE 802.15.4 standard is one of the main communication protocols proposed for wireless senso... more The IEEE 802.15.4 standard is one of the main communication protocols proposed for wireless sensor networks, IoT 'Internet of Things' and WoT 'Web of Things'. This protocol provides a flexible MAC layer designed to meet a variety of applications. Since WSN is application-specific, it's very difficult to provide a generic solution for all types of applications and topologies. In this work we focus on delay sensitive applications in star networks. This topology is used in wireless sensor networks for monitoring and control applications. The IEEE 802.15.4 standard provides some quality of service features for real-time data transmission. We identified some limitations of this standard and we proposed an improvement to provide a lower end-to-end delay with respect to energy consumption constraint by optimizing MAC layer. The experimentations are done using the NS-2 simulator. The results show the improvements expected by our approach among the IEEE 802.15.4 MAC standard.

International Journal of Advancements in Computing Technology, 2013

Journal of Software, 2014

Wireless sensor network (WSN) has been used in widespread domains, and the real-time response is ... more Wireless sensor network (WSN) has been used in widespread domains, and the real-time response is required by many WSN applications. However, due to the memory resources limitation on the sensor nodes, the current WSN OSs such as TinyOS, Contiki, SOS, mantisOS, etc., are not real-time ones. To achieve the objective of designing a realtime OS with low memory resource consumption, a new WSN OS named HEROS is developed and presented in this paper. For HEROS, it adopts a hybrid scheduling strategy. Both the event-driven and multithreading schedulers are implemented in parallel, and these two schedulers can switch to each other when necessary. By this means, HEROS take advantages of both the event-driven system's low memory resource consumption as well as multithreading system's high real-time performance. Besides these, HEROS uncouples the applications from the underlying systems by using the pre-linked mechanism (PLM). With this mechanism, a user-friendly development environment can be provided to the WSN users. Finally, to evaluate the performance of HEROS, it is compared with some other WSN OSs on the iLive platform (8-bit AVR microcontroller). The final experimental and evaluation results prove that HEROS is a memory resources efficient, real-time supported and user-friendly OS, and can be used on most resource-constrained sensor nodes to support the diverse kinds of WSN applications.

2012 9th International Conference on Ubiquitous Intelligence and Computing and 9th International Conference on Autonomic and Trusted Computing, 2012

ABSTRACT Wireless Sensor Networks (WSNs) have played an important role in diverse domains. Howeve... more ABSTRACT Wireless Sensor Networks (WSNs) have played an important role in diverse domains. However, programming on WSN nodes are quite hard because currently there exist no standard software and hardware platforms in WSN. Thus it's essential to build a software infrastructure that can provide a decent development environment to the users. One sound choice to achieve this objective is to deploy embedded Java virtual machine (EJVM) on the WSN nodes. However, most sensor nodes are resources-constrained devices and WSN applications have some essential performance requirements as well, the feasibility of applying any EJVM on a WSN platform should be evaluated in advance. In this paper, an EJVM simpleRTJ is researched, chosen, ported and enhanced on the Live node platform equipped with AT91SAM7S256 micro controller. The experimental work proves that simpleRTJ is an advisable method for providing a decent WSN development environment. Yet the observed drawbacks such as the non-trivial RAM resource requirement and low executive efficiency restrict its employment on the high memory and energy resources constrained sensor nodes, e.g., the ones equipped with the micro controller ATMEGA1281. To address this challenge, an efficient middleware EMIDE is implemented complementally to substitute EJVM for meeting the challenge of implementation on the high resources-constrained WSN platforms. The performance evaluation work proves that EMIDE is an effective method to provide a decent WSN development environment as well as capable to be applied on the high resources-constrained sensor platforms.

Visual Communications and Image Processing '93, 1993

Sensors (Basel, Switzerland), Jan 22, 2014

Operating system (OS) technology is significant for the proliferation of the wireless sensor netw... more Operating system (OS) technology is significant for the proliferation of the wireless sensor network (WSN). With an outstanding OS; the constrained WSN resources (processor; memory and energy) can be utilized efficiently. Moreover; the user application development can be served soundly. In this article; a new hybrid; real-time; memory-efficient; energy-efficient; user-friendly and fault-tolerant WSN OS MIROS is designed and implemented. MIROS implements the hybrid scheduler and the dynamic memory allocator. Real-time scheduling can thus be achieved with low memory consumption. In addition; it implements a mid-layer software EMIDE (Efficient Mid-layer Software for User-Friendly Application Development Environment) to decouple the WSN application from the low-level system. The application programming process can consequently be simplified and the application reprogramming performance improved. Moreover; it combines both the software and the multi-core hardware techniques to conserve t...

Bio-medical materials and engineering, 2014

As the symptoms and signs of heart diseases that cause sudden cardiac death, cardiac arrhythmia h... more As the symptoms and signs of heart diseases that cause sudden cardiac death, cardiac arrhythmia has attracted great attention. Due to limitations in time and space, traditional approaches to cardiac arrhythmias detection fail to provide a real-time continuous monitoring and testing service applicable in different environmental conditions. Integrated with the latest technologies in ECG (electrocardiograph) analysis and medical care, the pervasive computing technology makes possible the ubiquitous cardiac care services, and thus brings about new technical challenges, especially in the formation of cardiac care architecture and realization of the real-time automatic ECG detection algorithm dedicated to care devices. In this paper, a ubiquitous cardiac care prototype system is presented with its architecture framework well elaborated. This prototype system has been tested and evaluated in all the clinical-/home-/outdoor-care modes with a satisfactory performance in providing real-time c...