Seol Young Jeong

Fully Distributed Monitoring Architecture Supporting Multiple Trackees and Trackers in Indoor Mobile Asset Management Application

A tracking service like asset management is essential in a dynamic hospital environment consisting of numerous mobile assets (e.g., wheelchairs or infusion pumps) that are continuously relocated throughout a hospital. The tracking service is accomplished based on the key technologies of an indoor location-based service (LBS), such as locating and monitoring multiple mobile targets inside a building in real time. An indoor LBS such as a tracking service entails numerous resource lookups being requested concurrently and frequently from several locations, as well as a network infrastructure requiring support for high scalability in indoor environments. A traditional centralized architecture needs to maintain a geographic map of the entire building or complex in its central server, which can cause low scalability and traffic congestion. This paper presents a self-organizing and fully distributed indoor mobile asset management (MAM) platform, and proposes an architecture for multiple trackees (such as mobile assets) and trackers based on the proposed distributed platform in real time. In order to verify the suggested platform, scalability performance according to increases in the number of concurrent lookups was evaluated in a real test bed. Tracking latency and traffic load ratio in the proposed tracking architecture was also evaluated.

Remote service discovery and binding architecture for soft real-time QoS in indoor location-based service

Indoor location-based service (LBS) is generally distinguished from web services that have no physical location and user context. In particular, various resources have dynamic and frequent mobility in indoor environments. In addition, an indoor LBS includes numerous service lookups being requested concurrently and frequently from several locations, even through a network infrastructure requiring high scalability in indoor environments. The traditional centralized LBS approach needs to maintain a geographical map of the entire building or complex in its central server, which can cause low scalability and traffic congestion. This paper presents a self-organizing and fully distributed indoor LBS platform with regional cooperation among devices. A service lookup algorithm based on the proposed distributed architecture searches for the shortest physical path to the nearest service resource. A continuous service binding mechanism guarantees a probabilistic real-time QoS regardless of dynamic and frequent mobility in a soft real-time system such as an indoor LBS. Performance evaluation of the proposed algorithm and platform is compared to the traditional centralized architecture in the experimental evaluation of scalability and real test bed environments.

Self-Organizing Wearable Device Platform for Assisting and Reminding Humans in Real Time

Most older persons would prefer “aging in my place,” that is, to remain in good health and live independently in their own home as long as possible. For assisting the independent living of older people, the ability to gather and analyze a user’s daily activity data would constitute a significant technical advance, enhancing their quality of life. However, the general approach based on centralized server has several problems such as the usage complexity, the high price of deployment and expansion, and the difficulty in identifying an individual person. To address these problems, we propose a wearable device platform for the life assistance of older persons that automatically records and analyzes their daily activity without intentional human intervention or a centralized server (i.e., cloud server). The proposed platform contains self-organizing protocols, Delay-Tolerant Messaging system, knowledge-based analysis and alerting for daily activities, and a hardware platform that provides low power consumption. We implemented a prototype smart watch, called Personal Activity Assisting and Reminding (PAAR), as a testbed for the proposed platform, and evaluated the power consumption and the service time of example scenarios.

Self-organizing distributed architecture supporting dynamic space expanding and reducing in indoor LBS environment.

Indoor location-based services (iLBS) are extremely dynamic and changeable, and include numerous resources and mobile devices. In particular, the network infrastructure requires support for high scalability in the indoor environment, and various resource lookups are requested concurrently and frequently from several locations based on the dynamic network environment. A traditional map-based centralized approach for iLBSs has several disadvantages: it requires global knowledge to maintain a complete geographic indoor map; the central server is a single point of failure; it can also cause low scalability and traffic congestion; and it is hard to adapt to a change of service area in real time. This paper proposes a self-organizing and fully distributed platform for iLBSs. The proposed self-organizing distributed platform provides a dynamic reconfiguration of locality accuracy and service coverage by expanding and contracting dynamically. In order to verify the suggested platform, scalability performance according to the number of inserted or deleted nodes composing the dynamic infrastructure was evaluated through a simulation similar to the real environment.

Proximity-Based Asynchronous Messaging Platform for Location-Based Internet of Things Service

The Internet of Things (IoT) opens up tremendous opportunities to provide location-based applications. However, despite the services around a user being physically adjacent, common IoT platforms use a centralized structure, like a cloud-computing architecture, which transfers large amounts of data to a central server. This raises problems, such as traffic concentration, long service latency, and high communication cost. In this paper, we propose a physical distance-based asynchronous messaging platform that specializes in processing personalized data and location-based messages. The proposed system disperses traffic using a location-based message-delivery protocol, and has high stability.

A Middleware Architecture for Dynamic Reconfiguration of Agent Collaboration Spaces in Indoor Location-Aware Applications

Recently, indoor location-aware applications that provide interactive capability with the surrounding physical environment are increasingly in demand. These applications include mobile asset management, indoor navigation, and location-based reservation systems. In many cases, these services require multiple and dynamic collaborations over a large number of service subscribers with a deterministic, fast response time. However, many studies still function primarily on client/server-based centralized architectures that are inefficient in supporting complex collaboration, due to their static organization and unpredictable network congestion. To address this problem, we propose a middleware architecture named Dynamic Reconfigurable Agent Space (DRAS), based on a collaboration of service agents that can be distributed over the requested service area. A service application can dynamically modify a service area according to the request of the service subscribers under the DRAS. To demonstrate the feasibility and performance of the DRAS, we evaluated the elapsed time for dynamic reconfiguration of the service area. Also, two general collaboration scenarios in indoor location-aware applications called voting and tracking were evaluated in the simulation and in a real environment. The evaluation shows that the proposed middleware is suitable for indoor location-aware applications that require a large number of mobile nodes and complex collaboration by the effective distribution of network traffic and processing around the service agents.

Dynamic resource look-up and discovery architecture for indoor location-based service

Recently, in the large indoor environment, such as hospital, office building and factory, there are numerous resources (e.g. wheelchair, printer, fire extinguisher, etc.). To use these resources, a user needs to search and track its location. In the legacy architecture for the location based service(LBS), its server can be unstable due to the traffic congestion as the system load increasing, which can cause a single point of failure problem. To solve these problems, we propose a dynamic resource look-up and discovery architecture with the concept of self-organizing, which occurs naturally in spontaneous environment. By applying the self-organizing feature, we can guarantee both scalability and user-friendliness in the LBS.

Actual Travel Path Based Room Connectivity Graph Generation

Indoor Location-Based Services (LBS) inevitably require the map of the target indoor environment. Manually designed map is generally used for the purpose in the legacy indoor LBS application. However, this approach is not easy to acquire the dynamic knowledge from the environment such as preferred moving path, traffic of walkers and temporal blocked area. In this paper, we proposed a new method that automatically collects the room connectivity graph with the distance and traffic factor as weight of edge. In order to achieve the dynamic information, we use the actual travel path of the mobile node worn by a resident of the indoor environment. As the experimental evaluation, our proposed method could easily achieve the dynamic indoor map information only using the self-organized interactions between stationary nodes and mobile nodes, such as watch, worn by residents.

Dynamic Reconfigurable Hub as a Stationary Node in a Hybrid Sensor Network

Sensor network systems are being expanded with the development of technology for the design of a low-power chips and for operating sensor networks. However, it is difficult to modify or change an application for a stationary sensor node after installation in the field. Furthermore, there is a limit to installation after developing and testing a new sensor node if it needs to reconfigure the software and hardware of the existing sensor node. Therefore, not only is software reconfiguration needed but also dynamic hardware reconfiguration for various changes in requirements, such as sensor type, communication bandwidth, quality of service, or reduced power consumption depending on the changing environment and requirements of users. This paper proposes a specially designed stationary node called a SMART (system management architecture for reconfigurable technology) node, which is capable of dynamic reconfiguration of the various sensing functions or communication protocols. The SMART node can provide suitable service and change the communication protocol according to various surroundings and user requirements.

Homecare kit platform supporting multiple bio-signals acquisition and analysis in daily-life

In the ageing society, medical service has changed from the “cure-service” for patients to the “care-service” for semi-healthy or healthy people. The care service for healthy people in daily-life requires using a homecare kit to measure and analyze their personal bio-signal in daily activities. The acquisition signal in daily-life can help detect early symptoms of disease and enable their cure. In this paper, we propose a homecare kit based cloud platform for the acquisition, analysis and management of the multiple bio-signals from daily-life activity, and for sending alerts to another user (guardian) or doctor when a dangerous situation occurs. In the proposed platform, the homecare kit consists of wearable devices with embedded biosensors: ACC, PPG/SpO2, Breathing, ECG, and the user can easily wear and use the homecare kit for measuring the bio-signal in daily life or while sleeping. If the user is a patient with a disease such as arrhythmias, during a dangerous situation such as breaking down or a stop in breathing, the alert messaging service can alert the asynchronous push message to the registered guardian or doctor. In the hospital, healthcare professional staff can also analyze the stacked bio-signal from a users daily life and can prescribe for personal living. For the verification of the implemented homecare kit, a sleep apnea patient actually wore our homecare kit and polysomnography equipment simultaneously in the hospital. We evaluated the equipment equivalence based on the analysis result and acquisition bio-signal.