Hideki Sunahara

• PhD.
• Professor (Full) at Keio University

Internet-native audio-visual services are witnessing rapid development. Among these services, object-based audio-visual services are gaining importance. In 2014, we established the Software Defined Media (SDM) consortium to target new research areas and markets involving object-based digital media and Internet-by-design audio-visual environments. I...

This paper introduces the concept of "Social Thing" where things have unique personalities and autonomously build network to cooperate with each other as if they are living entities. In this context, each thing has its goal and different level of smartness. They autonomously cooperate to achieve their goals through inter-thing communication. This p...

This paper provides a design of scalable and simple remote security exercise system and its performances. Serious understaffing problem in security area. Basic security skills are necessary to all people these days. We have two fundamental problems to solve this problem.

In this study, we focus on the accurate and early prediction of Localized Heavy Rain (LHR) using multiple sensors. Traditional sensors, such as rain gauges and radar, cannot detect LHR until cumulonimbus clouds cover the sensors. In contrast, Surface Meteorological Monitoring Networks (SMMNs) can accurately measure rainfall in the vicinity of the s...

hough there are many examples of attempts to create interactive lighting installations in urban public space, its meaning for urbanites has not been fully explored and defined. What could interactive lighting contribute to urban public space? Using the concept of Third Place, this research focuses on the social potential of urban public space using...

Resource discovery is an essential function for distributed mobile applications integrated in vehicular communication systems. Key requirements of the mobile resource discovery are wide-area geographic-based discovery and scalable resource discovery not only inside a vehicular ad-hoc network but also through the Internet. While a number of resource...

This paper presents theoretical and experimental study on feasibility of public service for DTV idle space called DTV white space in Korea. We conducted the in-depth interview of the experts who work for the stakeholders at the related fields, such as government, broadcaster, Telco, and academia. Through the interview, we achieved the research purp...

The continuous balancing of energy demand and supply is a fundamental prerequisite for the stability of energy grids. Photovoltaic power generation (PV) is one of the key components. Therefore, it is important to know 1) in what way and how much electricity can be generated by PV at real-time, and 2) how households' behavior can be changed by displ...

Some idle spaces in the TV band, the so-called Digital Dividend have emerged through the TV channel rear- rangement process as the one of the activities for DTV transition. Various wideband services including spectrum sensing application are currently being reviewed as DTV White Space application in order to cope with the wireless internet envi- ro...

In this paper, a DTV interference test was performed in order to measure the affected ranges of the DTV service that result from the operating of a narrowband system as a DTV White Space Service under severe environmental conditions. The DTV coexistence testing was performed in order to review the degree of DTV signal degradation depending on the b...

In recent years home gardening is becoming popular in Japan. In contrast to the popularity, the percentage of the beginners who are unsatisfied with growing vegetables is high. There are two reasons for this problem. One is the conditions of individual environment for home gardening are not fulfilled. The other issue is that the beginners do not fu...

Efficient use of digital TV spectrum is becoming one of global issues when the transition to DTV is completed. Various wideband services including spectrum sensing application are mainly discussed currently. However, there are critical issues with broadcasters as incumbent users in the DTV band. Therefore, the narrowband applications should also be...

Under the Web 2.0 movement, situational applications are now developed by 'mushup' technique. Then, open standard protocol to authorize delegeted access by a web servise to protected resoueces on other web server became required. We will explain about the evolution prcess of OAuth protocol specification. Viewpoints of security and that of easy impl...

As sensor and wireless network technologies are developed, it is expected that we will be able to gather lots of sensor data from various sensors on globe. Combining/ aggregating these sensor data, many useful applications could be developed. However, it is difficult to aggregate sensor data and secure scalability, because in some case too much sen...

This paper proposes a direction for a White Space management scheme to enhance spectrum efficiency by considering unoccupied channel conditions according to the density of DTV transmitters and relays. Unoccupied channels are predicted to foresee White Space within three pilot areas, Uljin, Gangjin and Danyang, in Korea. We considered two DTV servic...

In recent years, everybody can get many kinds of real-time digital information easily, especially by using API as an infrastructure system which provides information data sets via the Internet. This system has changed a style of spreading information on the Internet. In a case of web developers, they utilize the real-time data sets which are create...

Recently, Cloud computing has emerged as a new computing paradigm on the Internet. Cloud computing facilitates flexible and efficient computer resource management via virtualization technologies at anytime and from anywhere, so that users can add and/or delete IT resources. Users can set up and boot the required resources and they have to pay only...

In this paper, we have investigated the possibility of coexistence of terrestrial truncated radio (TETRA) as a narrow band system with digital television (DTV) in TV white spaces. Based on the system operation mode of a TETRA system, trunked mode operation (TMO) and direct mode operation (DMO), the interoperable power range of fixed and mobile term...

Some countries have already finished or are progressing toward a transition to Digital Television (DTV). In particular, the US and UK have conducted technical analyses of white space, and its management strategy is under review. They are also working on determining what kind of service could be used for white space. According to this trend, a speci...

We already know that a total solar eclipse show at July 22th 2009 will be one of the most-watched events in our lifetime. There were some kinds of event and trials of video transmission for the total solar eclipse. We were involved in joint research for IP network transmission experimentation of a whole sky 4K Ultra High Definition image between NA...

We have designed and developed MetaFa as the metadata management system on wide-area network. The MetaFa offers the data access method for desired data using the metadata. In this paper, we propose "personal view namespace file system" (PVN-FS) which is enable to flexible data access based on characteristics and semantics of data. The PVN-FS is ena...

We add data processing components onto content-based networks. Content-based networks provide publish/subscribe system in distributed environment and appropriate for notifications and alerts. If content-based networks process published data and create meaningful information, this system enhance the application fields in ubiquitous sensing environme...

This research develops an Autonomous Distributed and Cooperative disaster information system based on the Internet technologies which distribute sensor information such as meteorological information. It is essential that disaster prevention systems collect and classify information or deliver to local residents rapidly. However, there are some probl...

Due to the global spread of the Internet and the rapidly diminishing price of wireless sensors, a large number of heterogeneous sensor networks have been developed and interconnected around the globe for the sharing of sensing data on a global scale. Such data greatly affect our daily lives, such as environmental issues and business development. A...

Structured overlay networks are widely used as platforms for distributed systems. However, in a high churn situation, it is highly costly to maintain the structure and service availability of an overlay network because there is a limitation in churn handling. Several cooperation mechanisms among overlay networks are proposed to improve service avai...

In this paper we describe a smooth switching mechanism for enhancing the performance and low-waste traffic of distributed peer-to-peer video streaming. The mechanism was designed for when streaming topology set up a backup link and a predicted link to avoid being congested link each nodes. Furthermore this provides a Dominant Keyword procedure whic...

Many development tools for P2P applications are proposed, but do not address a problem of connection between unconnectable nodes. The problem is that, IPv4 nodes and IPv6 nodes cannot be directly connected. We propose a development tool with ReverseLink and RelayLink. For example, with our tool, NATed node can connect other NATed node throught a IP...

In recent years, sensors have become smaller, more affordable, and widely used. Also, Internet spreads all over the globe, and made possible transfer large data instantly. Thereby, large scale weather sensor networks have been constructible. In this kind of sensor network, we need to consider load balancing, network redundancy, and reliability of s...

Video conferencing in mobile environments involves real time streaming information among mobile nodes connected within a wireless environment. This kind of framework is difficult to deal with, because of its concrete requirements. In this paper, we propose an architecture based on adaptive applications that will change their behavior depending on t...

In this paper, we propose the wireless LAN system using the airship. The wireless LAN system on the airship is tracked by the image processing automatically and provided the Internet connectivity to users on the ground in our proposed system. We describe the requirements of the wireless LAN system for the airship and design the architecture. To est...

The data-intensive applications are naturally executed on the Internet and generate a huge amount of data. The generated data would be stored distributed storages. In such environments, a user cannot easily find the target data by only filenames. The metadata is very useful to represent the characteristics and semantics of data. If users can specif...

Interaction between emergency medical technicians (EMTs) and doctors is essential in emergency medical care. Doctors require diverse information related to a patient to provide efficient aid. In 2005, we started the Ikoma119 project and have developed a ubiquitous communication platform for emergency medical care called Mobile ER. Our platform, whi...

There are various kinds of learning systems in the world and quite a lot of them are using video sources. Also, those video sources have many kinds according to the content of learning and aim. In this paper, I'd like to describe the usability of learning systems by using a super high definition video source focusing on making handling of video sou...

Distributed hash table (DHT) is a specialized distributed system that aims to lookup hashed identifiers efficiently in order to route messages to and from the corresponding nodes and objects. However DHTs are mechanisms sensitive to churn (the continuous and interleaved process of arrival / departure of nodes). As a result, they often cause loss of...

In this paper, we propose a new architecture for optimizing the traffic of video streams in wireless mobile environments by providing environmental information locally to the application running on each mobile node. With such information, the application can adapt the quality of video streams.

The data-intensive computing generates a huge number of data in wide area network. The DataGrid technology tries to manage such distributed data on the Internet to provide the quick and efficient data search/access mechanism. The difficulties of the data access on DataGrid systems is caused from the differences in the data management manner and pol...

Narcolepsy patients often access the Internet using key words mostly consisting of common symptoms in order to further learn about their disease. Although information from diverse sources floods the Internet, the quality of narcolepsy-related information appears to have improved, and harmful information does not often enter the top access rankings....

The Probe Vehicle Information system is as system that collects information from cars equipped with sensors. Usually, various information is collected and transferred to a server, at frequent intervals. The information includes when and where the information was collected, which could lead to privacy problems. One way to solve these problems, is to...

To handle ubiquitous sensor data, we have been developing a geographicallocation- based P2P network called “Mill”. In a ubiquitous sensing environment, data manipulation by users and sensing devices may have some characteristics. For example, sensor data are constantly generated and users keep getting these data in a particular region. When handlin...

Location based services attract a great deal of attention. Existing location based service, however, rely on the dedicated positioning devices and location representations although people use several kinds of location representations such as the room number, the shop name, and latitude/longitude. This paper proposes universal location platform (ULP...

There have been many wireless sensors equipped IEEE 802.15.4. ZigBee, the most representative upper layer protocol of IEEE 802.15.4 is non-IP-based. However an IPv6 protocol called 6LoWPAN is currently being discussed by the IETF. Until now, IP stacks have generally been too large for sensor devices, which have weak calculating ability. Thus, most...

Conventional Peer-to-peer networks have been focusing on managing large size files, such as musics, movies, or DVD images. On the other hand, huge numbers of tiny data are generated by sensing devices existing all over the globe. To manage these types of data, P2P networks should shift the strategy to construct an overlay and process queries, becau...

To enable an outdoor user to acquire mobile specific information, an information retrieval system should provide contents that reflect user's circumstance such as user's position and time. There are a lot of information services that can provide contents based on geographical location. But, about temporal information, there is few works, because th...

The Mobile environment has been improved in this decade with technologies of mobility transparency such as Mobile IP (MIP) and Network Mobility (NEMO), plus there has been progress in wireless and device technologies. Mobility transparency makes it possible for a mobile node to change its upstream data-link without any disruption of existing TCP co...

In this paper, the authors propose a high-speed implementation of a parameter filter, using a multidimensional space search algorithm with the introduction of virtual bounding rectangles. The authors have proposed and implemented a KUPF architecture for the problem of packet classification reflecting the complex policies of a router. Because parame...

SUMMARY With the rapid rise in the demand for location related service, communication devices such as PDAs or cellar phones must be able to search and manage information related to the geographical location. To leverage location-related infor- mation is useful to get an in-depth perspective on environmental circumstances, such as trac conditions or...

Nowadays, automobiles have a role as a sensor aggregation which is used to grasp the circumstance and its location information. The value from vehicle sensors on each vehicle is called probe data. Organically-consolidated probe data which make social seminal information is deserving of societal expectation. These probe vehicle system also known as...

The Live E! project is an open research consortium among industry and academia to explore the platform to share the digital information related with the Earth and our living environment. We have getting a lot of low cost sensor nodes with Internet connectivity. The deployment of broadband and ubiquitous networks will enable autonomous and global di...

The availability of cheap and smart wireless sensing devices provides unprecedented possibilities to monitor the physical world. On the technical side these devices introduce several original research problems, many of them related to the integration ...

Development of sensor technology enables us to use lots of and detailed information. Then, it is difficult to deal with the vast number of information generated by sensors by client server model. In order to deal with data generated by sensors, we build a new information infrastructure on overlay network. In this paper, we propose an overlay networ...

Nowadays, automobiles have a role as a sensor aggregation which is used to grasp the circumstance and its locational information. The value from sensors on each vehicle is called probe data. Organically-consolidated probe data which make social seminal information is deserving of societal expectation. These probe vehicle systems also known as float...

The Live E! project, www.live-e.org, is an open research consortium among industry and academia to explore the platform to share the digital information related with the Earth and our living environment. We have getting a lot of low cost sensor nodes with Internet connectivity. The deployment of broadband and ubiquitous networks will enable autonom...

The Live E! project is an open research consortium among industry and academia to explore the platform to share the digital information related with the earth and our living environment. We have getting a lot of low cost sensor nodes with Internet connectivity. The deployment of broadband and ubiquitous networks will enable autonomous and global di...

Recently, Technology of sensor networks develops rapidly. In addition, people have started utilizing many kinds of sensors. Sensors independently collect environmental information all over the world. Unfortunately those sensed data are not shared and open to the public. Therefore, we have constructed super-large-scale sensor network system to share...

To leverage location-related information is useful to get an in-depth perspective on environmental circumstances, traffic situations and/or other problems. To handle the large number of information and queries communication devices issue, some scalable mechanism must be required. In this paper, we propose a peer-to-peer network system called "Mill"...

In recent years, simulation using computer systems has been of increasing importance in the life sciences. We have developed a system called "Rokky-G" that facilitates a protein structure prediction strategy called "Rokky" on Grid systems. Rokky-G provides the framework of protein structure prediction on the Grid. In this paper we discuss the archi...

It is vital to achieve a disaster recovery system that allows a backup site to take over a primary site's IT services while the primary site is down. We propose a flexible replication mechanism based on service requirements such as system performance, recovery time objective (RTO), and recovery point objective (RPO). For high flexibility, the mecha...

Effective management of the quality of multimedia streaming service is a challenging issue. Traditionally, many server operators rely on their intuition for the service quality management because the quantitative semantics of the server log data has not been explored. In this paper, we propose a new approach to quantitative estimation of the client...

To search the contents through WWW in consideration of user's circumstance condition, search engines should make use of some information such as current time, user's location, user's schedule and so on. We propose an information retrieval method that effectively uses both user's and content's metadata based on TPO (time, position, occasion). We imp...

Personal computing with affordable computers and their peripheral devices becomes more popular. To use such devices more efficiently and improve their usability, peo- ple want to share surrounding peripheral devices between computers without any modification of their own comput- ing environments. The recent device sharing technologies in the pervas...

The paper describes a computing system for a protein structure prediction and a case study of its system. Scientists of protein structure prediction have to do execution applications for protein structure prediction by trial-and-error process. For the purpose of doing execution applications by trial-and-error process, we propose a computing system...

As personal computing becomes more popular and affordable, the availability of peripheral devices is also increasing rapidly. However, these peripheral devices can usually only be connected to a single machine at time. The ability to share peripheral devices between computers without any modification of existing computing environments is, consequen...

In this paper, we describe a new telepresence system which enables a user to look around a virtualized real world easily in network environments. The proposed system includes omni-directional video viewers on web browsers and allows the user to look around the omni-directional video contents on the web browsers. The omni-directional video viewer is...

The Nara Institute of Science and Technology (NAIST) user Authorization management System for network accesses (NAS) was designed and developed as a campus-network management system for administrators who are not information and communications technology (ICT) experts. Student residents have successfully operated the system in the dormitory network...

In recent years, the Internet is increasing a role of the social infrastructure with maintaining of spread and communication environment. Various usages are increasing with the infrastructure. Currently, necessity is arising for system offering the service of decision of the policy with diversification and change of usages. The system is increasing...

As Internet access had spread, it has become an important potential means of lifeline communication. The Internet can fulfill a role in the everyday life of citizens by offering lifeline communication services such as the police, ambulance, gas, electricity, and water services when an emergency occurs. In these lifeline communications, a caller nee...

Recently, the telepresence which allows us to experience a remote site through a virtualized real world has been investigated. We have already proposed telepresence systems using omni-directional images which enable the user to look around a virtualized dynamic real scene. The system gives the feeling of high presence to the user. However, conventi...

The spread of the Internet has made it important as a potential means of lifeline communication. The Internet can fulfill a role in the everyday life of citizens by offering lifeline communication services such as the police, ambulance, gas, electricity, water service when an emergency occurs. In these lifeline communications, a caller needs to be...

Emergency communication support on the Internet is an important task. In the event of an emergency, such as a disaster, accepting as many VoIP calls as possible in limited bandwidth is an important requirement. Another important requirement is providing high quality service for important communications (ex. 911 services in the US). But, for non-eme...

This paper describes the system which enables the users to see outdoor scene at remote site by an omni-directional camera on a car. We had researched telepresence system using an omni-directional camera and the network. The system enables multiple users to see arbitrary direction using a fixed camera. This paper describes the improved system which...

"Campus grid" consists of a collection of computing resources distributed over a university-wide network. To use computing resources on campus grid efficiently, we propose the node selection mechanism based on the usage pattern of computational nodes in campus grid. In our node selection mechanism, we represent the usage pattern of a computational...

We envisage that most of the subway train services or roadways in the near future will provide wireless coverage to commuters. This will drive the need for content providers to offer seamless mobile web services !ilce streaming video et for mobile computers and handheld devices. We see a huge potential in providing the next generation services base...

The vehicle environment is a good testbed to investigate Internet mobility technologies. Based on testing of buildings, protocol implementation details and problems to deploy it are clarified. This paper describes them. The InternetCAR Project had already done testing to connect vehicles to the IPv6 Internet. Some applications including vehicle dia...

Internet use has expanded in both social and corporate activity and is becoming indispensable to people's lives as it gains in importance and popularity. Consequently, the demand for using the Internet as a communication lifeline is increasing. In lifeline support, emergency and/or important communication is the top priority. By transferring comple...

With the spread of IPv6 technology, we can use various IPv6 servers such as WWW and mail. Therefore, a network administrator should measure both IPv6 and IPv4 network and server. We discuss existing measurement tools to use in an IPv6 environment, considering WWW that is the most important service on the Internet. We express a new benchmark system...

With the advance of computing and internetworking technologies, various services, which need classification of data, are provided. Firewall and QoS control are typical services which classify the data flow. These services are based on two or more rules, and select a rule to classify the data. However, some of their rules may conflict with one anoth...

There are many peripheral devices attached locally to computers. These devices are controlled by device drivers in some operating systems and most of these devices do not provide functions for remote usage over the network. Several technologies allow us to trans- parently use remote devices in the kernel. However there is often a limitation on the...

A distributed WWW caching system based on Internet Cache Protocol (ICP) is a system where a cache of a single proxy server is shared by others. When a proxy server receives an HTTP request for an object but it does not store the object locally in its cache, it sends queries to other proxies. However, the system causes a problem that many ICP messag...

Internet becomes popular, and many network servers are standing up. These network servers are evolving to large scale servers, because they provide many services such as broadcast of several events, reservation of a travel ticket and so on. Server administrators should offer stable service to users. In addition, requests from clients are balanced t...

In this paper, we discuss the scalability issues arising in distributed WWW caching systems that exchange meta information among caching proxies using Internet Cache Protocol (ICP). One of the main objectives of WWW caching systems is to reduce WWW traffic on the Internet. Since the traffic generated by ICP does not usually convey WWW objects, it m...

As the Internet is becoming more popular, many network servers are emerging. These network servers are evolving to large scale servers because they provide many services such as broadcasting of several events, reservation of a travel ticket and so on. Server administrators should offer stable service to users. In addition, requests from clients are...

From the standpoint of server operation, performance measurement of the server is important. One of the major parts of the measurement is kernel monitoring, and most server administrators have been legacy tools that can influence server performance by the load itself. We describe the design and implementation of a new kernel monitoring system that...

We examine the delay performance of packets from constant-bit-rate (CBR) traffic whose delay is affected by non-real-time traffic. The delay performance is analyzed by solving the nD/D/1 queue with vacations. We obtain an exact and closed form solution, hence obviating the need of any approximations or numerical Laplace inversions. We then provide...

We examine delay performance of packets from constant bit rate (CBR) traffic whose delay is affected by non-real-time traffic. The delay performance is analyzed by solving the ΣD i/G/1 queue with vacations. Our analysis allows heterogeneous service time and heterogeneous interarrival time. Thus, we can get the impact of packet length of a stream on...

It is important to obtain the information about residual lignin (RL) in kraft pulp in order to clarify the mechanism of formation of organic chlorine compounds in the bleaching process and to develop a non-chlorine bleaching method. The RL was isolated from eucalyptus (Eucalyptus camaldulensis) kraft pulp (screened yield: 47.3%, kappa number: 14.4)...

In this paper, we report results of our study with respect to the number of wavelength division multiplexer/demultiplexers that should be provided in optical cross-connect switches (optical XCs) installed in the nodes of optical wavelength multiplexed transmission networks. Optical XCs perform the switching and add/drop operations of optical signal...

ternetworking environments. key words: mobile computing, dynamic adaptation, networking 1. Introduction In the good oldda ys, computing environment wa sta6[: Applicaq'1 prograq'1[ know b eforehaq the cha['Pq':j6KPa of the execution environment sucha s types of input devices or the resolution ofa gra11:2 displa y. Thus, they were aeP toestima: thea...

Introduction The world ent65 t6 era of global communicatOFq2 The Intq/78 is rapidly growing and has become a significant fundamentd infrast66K/q2 intq6 era. Especially, World-Wide Web (WWW) is tq most importfi t service on tq Int65K5F Therefore, providing WWW services witsqK anyt6fifiLOq becomes a more importfi t issue. To achieve WWW server operat...

In the networks of regular topology proposed in the past, such as BMSN or Shuffle Net, the number of nodes constituting the network is restricted, but GEMNET has wide expandability due to the fact that a network can have any number of nodes; it also is superior to other networks in the average hop count and throughput. However, in GEMNET, even when...