Kenya Sato

Content Sharing Among UPnP Gateways on Unstructured P2P Network Using Dynamic Overlay Topology Optimization

Such home networking technologies as UPnP have become common for users to connect their devices at home. In this paper, we propose Dynamic Overlay Topology Optimizing Content Search (DOTOCS) that enables flexible content searches while optimizing P2P overlay networks. DOTOCS allows nodes to change their logical links to reach other nodes that have frequent data transfers in fewer hops, providing users with a better chance of finding their desired contents in quicker downloading time. For this reason, DOTOCS is useful to establish efficient connections among UPnP gateways on unstructured P2P networks for content sharing. We implemented DOTOCS using a P2P simulator to evaluate and measure its performance. The simulation results proved that DOTOCS increases search performance by 30 to 40% compared with a simple content search method that omits optimization.

Implementation and Evaluation of Data Management Methods for Vehicle Control Systems

Vehicle control systems have recently emerged to provide drivers with safe driving and warnings of potential danger. Such systems are capable of determining the risk of collision with other vehicles and obstacles based on information from on-board sensors. These systems are often composed of many kinds of sensors whose data must be handled by on-board applications. Reusability and substitutability of these applications may be affected by data formatting dependencies, and the design and development of such systems is usually complex. In this study, we propose data management methods to reduce application complexity in vehicle control systems. To verify the feasibility of the methods, we implemented applications on the two types of data management methods: a database management method and a data stream management method. Both implementations were evaluated and discussed, we concluded that various queries were required by combining these two methods for vehicle control systems.

Routing and Address Assignment Using Lane/Position Information in a Vehicular Ad Hoc Network

Connection stability is important in vehicle-to-vehicle communication for applications that exchange messages for collision warning, cooperative driving, and other high-urgency purposes. Many of the existing communication protocols for mobile ad hoc networks assume the use of, portable gaming players, PDAs and other general-purpose devices, thus reducing the reliability of connection stability and communication. Therefore, greater efficiency can be expected by specializing systems for vehicle-to-vehicle communication using position information. To improve connection stability, we propose a method for constructing network groups according to lane position and evaluate the proposed method by simulation. We also describe a method of automatic assignment of IP addresses using IPv6 and a combination of network addresses defined for each lane and a specific host address for each vehicle.

Transparent upnp interactions over global network

Universal Plug and Play (UPnP) 1 has been proposed by Microsoft for realization of interactions among home appliances (e.g., TVs, air conditioners, and lighting devices) and information devices (e.g., PCs and PDAs) on a home local network. UPnP assumes to be used on a local network. Difficulties exist when establishing a communication link between two local networks across the Internet. In this paper, we propose a new device interaction method across the Internet with web service technology. We implement prototype system and make evaluation about latency.

AEDSMS: Automotive Embedded Data Stream Management System

Data stream management systems (DSMSs) are useful for the management and processing of continuous data at a high input rate with low latency. In the automotive domain, embedded systems use a variety of sensor data and communications from outside the vehicle to promote autonomous and safe driving. Thus, the software developed for these systems must be capable of handling large volumes of data and complex processing. At present, we are developing a platform for the integration and management of data in an automotive embedded system using a DSMS. However, compared with conventional DSMS fields, we have encountered new challenges such as precompiling queries when designing automotive systems (which demands time predictability), distributed stream processing in in-vehicle networks, and real-time scheduling and sensor data fusion by stream processing. Therefore, we developed an automotive embedded DSMS (AEDSMS) to address these challenges. The main contributions of the present study are: (1) a clear understanding of the challenges faced when introducing DSMSs into the automotive field; (2) the development of AEDSMS to tackle these challenges; and (3) an evaluation of AEDSMS during runtime using a driving assistance application.

Real-Time-Aware Embedded DSMS Applicable to Advanced Driver Assistance Systems

Automotive embedded systems are composed of many kinds of sensors, and it is becoming difficult to manage these data. Therefore, we define a vehicle data processing by a Stream Processing Description (SPD), which is the data processing description used in the Data Stream Management Systems (DSMS). However, because existing DSMSs run on generalpurpose systems, it is difficult to deploy DSMSs in automotive embedded systems and fulfill these performance requirements. The DSMS for automotive embedded systems (eDSMS) generates an optimized runtime from the queries defined by an SPD not dynamically (in execution) but statically (in development), which reduces the ROM/RAM usage. In this study, we extend eDSMS for real-time processing and show the extended eDSMS is applicable to the Advanced Driver Assistance Systems (ADAS).

Augmented Reality Marker for Operating Home Appliances

The popularity of network home appliances that can interconnect with other home appliances through networks increases. The operation and function of these appliances are complex since they can share contents and data with other network home appliances. However, it remains difficult for users to identify network home appliances, since their locations are not installed and cannot be displayed easily when operating them. Because these problems, more obvious and intuitive operations are needed for controlling network home appliances. For this solution, we have implemented augmented reality (AR) technology in our past proposed system for easier, intuitive operation to control multiple network home appliances connected by home networks. AR technology can provide virtual graphics and apply additional information to specific areas through camera displays. In current AR technology, an AR marker made from a graphical image (an image marker) is necessary to display the virtual AR graphics to the devicess identified location. Unfortunately, such image markers are not suitable when they are implemented on network home appliances due to poor recognition when lighting environments or distances are changed. In this paper, we explain the LED augmented reality marker (LED marker), implement a new marker, and evaluate it, and consider a collaboration system for controlling multiple network home appliances connected to home networks.

Vehicle Embedded Data Stream Processing Platform for Android Devices

Automotive information services utilizing vehicle data are rapidly expanding. However, there is currently no data centric software architecture that takes into account the scale and complexity of data involving numerous sensors. To address this issue, the authors have developed an in-vehicle data-stream management system for automotive embedded systems (eDSMS) as data centric software architecture. Providing the data stream functionalities to drivers and passengers are highly beneficial. This paper describes a vehicle embedded data stream processing platform for Android devices. The platform enables flexible query processing with a dataflow query language and extensible operator functions in the query language on the platform. The platform employs architecture independent of data stream schema in in-vehicle eDSMS to facilitate smoother Android application program development. This paper presents specifications and design of the query language and APIs of the platform, evaluate it, and discuss the results.

Visualization and control system for wireless network using augmented reality technology

There are various kinds of wireless network devices, such as cellular phone and wireless sensors, around us in a ubiquitous environment. Unlike a wired network, we cannot grasp the exact status of a wireless network in real space. Moreover, it is difficult to understand the relationships of connectivity intuitively, since network management software is used in a virtual two-dimensional space. We propose and implement EVANS (Embodied Visualization with AR for Network System) as a visualization system for wireless networks. EVANS shows the status of a wireless network on an interface that uses AR technology, which allows us to grasp the status among nodes intuitively. In addition, we can use EVANS to actually manipulate nodes in real space by manipulating the annotations on the AR interface.

Design and implementation of a vehicle interface protocol using an IEEE 1394 network

A wide variety of in-vehicle devices such as camera sensors, navigation systems, telematics and communication equipments have been incorporated into a vehicle to realize Intelligent Transport Systems (ITS) applications. Because an efficient standardized network is required, ITS Data Bus (IDB) has been discussed to carry high-speed multimedia data for audio, video and other real-time ITS applications. For connecting devices in a standardized manner, the IDB network has architecture with a gateway called vehicle interface which is located between automakers proprietary network and the standardized IDB network. IEEE 1394 (also known as iLink or FireWire), which can transport multimedia data for consumer electronics, is a good candidate for IDB network. In this paper, we analyze the issues for existing AV/C protocol (application layer protocol over IEEE 1394) to comprise the IDB network. In addition, we designed and implemented the vehicle interface protocol as a higher layer of IEEE 1394 to address the AV/C protocol issues for realizing the whole IDB network architecture.