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Initial conditions of trajectory calculation in studies of atmospheric transport are often arbitrary, leading to questions on applying trajectories to atmospheric observations of green house gases. We used observed methane on Hateruma Island in 1996–2000 as a tracer to investigate the quality of variety length of trajectories obtained from a three-dimensional (3D) and an isentropic (IS) model with different starting altitudes. The trajectory altitude is also considered in trajectory quality analysis. Our approach is to analyze the correlation between methane variation and the displacement of trajectory pairs. The study shows that the 3D model gives more accurate trajectories than the IS model, especially when long trajectories with high-altitude endpoints are to be used; and that a low starting altitude should be used for trajectory calculation by the IS model; however, for the 3D model a starting altitude close to the surface may affect trajectory quality due to the effect of zero vertical wind on the surface. The appropriate trajectory length for Hateruma Island is 78 h when the 3D model is used and 54 h when the IS model is used.

In situ measurement of atmospheric nitrous oxide (N 2 O) has been carried out at Hateruma monitoring station (lat 24°03 ′ N, long 123°48 ′ E) since March 1996 by the National Institute for Environmental Studies (NIES). A fully automated gas chromatograph equipped with an electron capture detector (ECD) measures the N 2 O concentrations at a frequency of 3 air samples per hour. Details of the experimental methods and procedures are presented in this paper. The N 2 O concentrations observed from March 1996 to February 1999 increased at an average rate of 0.64 ppb/yr. The observed data also suggest that there is a weak annual cycle of N 2 O concentration, increasing in autumn and winter and decreasing in spring and summer, with a peak-to-peak amplitude of at most 0.3 ppb. The N 2 O mixing ratios, smoothed with the 24-h running average, clearly showed short-term variability with synoptic timescales and had peak-to-peak amplitudes of about 1 ppb or less. These short-term variations correlated positively with the short-term variations of CO 2 during the period from winter to early spring when the air masses arriving at Hateruma are dominantly transported from the Asian continent. The ΔN 2 O/ΔCO 2 ratios could be used to constrain the relative strengths of these fluxes on a regional scale.

Raman spectroscopy and GC-MS analysis have been employed to examine the role of HCl and NH4 OH as a catalyst at the initial stage of the hydrolysis of Si(OCH3)4. Under the condition that the hydrolysis proceeded under the presence of amount of water less than theoretically required for the complete hydrolysis of Si(OCH3)4, H2O/Si(OCH3)4

In response to development of the communication environment, this, we previously developed a software-based real-time MPEG (Moving Picture Experts Group) system for streaming live video. We are now implementing this system in a videoconference system in our laboratory. For this system, we proposed a VOP decision-making algorithm that can adaptively choose the arrangement of VOPs (Video Object Planes) according to the CPU power of a terminal. When live movies from video cameras are streamed in real-time environments, such as a videoconference system, low latency is necessary so that users are not bothered by system latency. This means that the total latency of the system must be estimated, and the display time must be set accurately. In this paper, we report how to estimate the cost for time of encoding and communication when transmitting MPEG-4 objects in a real-time videoconference system using Gigabit Ethernet. For experiments, our results showed that our method can accurately estimate the encoding and communication latency.

We develop novel layer-3 (L3) Internet protocol (IP) packet switches to connect 80 Gbps WDM-based optical packet switching (OPS) networks with 10 Gbps Ethernet (10GbE). A L3 switch, which is the ingress edge node of the OPS network, generates an optical label according to a look-up table and the destination address of an IP packet, and then encapsulates the almost 10 Gbps IP packet into an 80 Gbps (8-wavelength x 10 Gbps) optical packet Another type of L3 switch, which is the egress edge node of the OPS network, decapsulates the IP packet from the optical packet and generates a lOGbE frame accommodating the IP packet according to a look-up table. We achieve the transmission of 7.2-Gbps IP packets throughput with a packet loss rate under 10-6 and demonstrate smooth UDP/IP-based 3D high-definition television (HDTV) video-streaming via the L3 switches and 80 Gbps WDM-based OPS system.

Peer-to-peer mobile video on-demand (P2MV0D) in the paper by Sato et al. (2006) showed one idea for the decentralized multimedia data distribution on the mobile environment. It allows a moving client to receive streaming data on demand from not only server but other moving clients in a peer-to-peer (P2P) manner, where video contents are divided into the same sized segment and aggregately sent and shared with as many receiving clients as possible. In this paper we discuss deploying P2MV0D under more real mobile environment, which has several delivery domains that have different amount of requests and several types of users that receive a video stream with different bandwidth. We employ the layered video cording and transmission schemes (Deering, 1993; McCanne et al., 1996; Li et al., 1998; Cheung and Zakhor, 1995) for P2MV0D to efficiently provide its service under such environment. The segment is further divided into smaller sized unit referred to as 'slice' and slicing and segmentation are carried out across the layered video streams. Mathematical analysis reveals this strategy reduces the traffic much better than simple use of P2MVOD

We demonstrate IP-packet/10-Gbit-Ethernet transporting by novel 80-Gbit/s/port optical packet switch prototype with IP/OP converters, packet-transceiver of instantaneous- locking (≪1 ns), and multiple-label-processor of ultra-fast processing (/spl Gt;100 ps) to achieve 7.2- Gbps IP-packet throughput with low packet-loss-rate (

This paper presents a new form of video on-demand called 'fragmented patching', which enables clients to move around freely even while receiving video. Patching techniques, which greatly reduce the required network bandwidth through multicasting, have potential for on-demand video distribution. However, patch-flow techniques based on unicast data are unsuitable for providing services to mobile clients because of the intricate process required for relatively short unicast flows to individually follow a moving client. In fragmented patching, however, patch flows are sent via broadcasting. In addition, to avoid increasing traffic due to broadcasting, the patch flows are broken down into segments, each of which is aggregated to be shared with as many multiple clients as possible. We compared the two techniques by using mathematical models, which present the average usage of link bandwidth with the traffic intensity (Erlang), and numerical analysis revealed the aggregation effect by segmenting patch flows countervails the increase in traffic caused by broadcasting patch flows.

The future vision distribution service (FVDS) (Sato, K. et al., Proc. 18th Int. Conf. on Advanced Inform. Networking and Application, 2004) is an innovative video delivery service concept based on the Internet ITS (intelligent transport system) area. Source mobility support multicasting (SMM) (Sato et al., IPSJ Journal, vol.45, no.2, 2004) consists of the new multicasting techniques needed to realize FVDS. However, FVDS and SMM lack sufficient application-level protocols to manage preceding and following vehicles on the same route and have a drawback of topological constraints in the access network to accommodate micro mobility. The paper presents two new protocols to solve these problems. The future vision distribution protocol (FVDP) is an application-level protocol that discovers a preceding vehicle on the same route and provides its multicast address for following vehicles by using information from the Global Positioning System (GPS) and a route guiding function. The self-organizing tree (SOT) protocol is a network-level protocol for use in the access network that organizes radio base-stations into a logical tree topology in a self-forming and self-healing manner. This eliminates the topological constraints and provides the network with robustness from failures and flexibility for network design.

Several technologies to deal with multi-object content (SMIL, MPEG-4 and so on) have been developed. A technology to control the quality of each object in multi-object content is still needed so that we can provide content that adapts to various situations. In addition, as broadband networks become increasingly sophisticated, it is more important to control content quality based on user requirements rather than just the available network bandwidth. In this paper, we propose a quality decision method based on user requirements for multi-object content delivery applications. We assume that content creators and receivers use the application and they give priorities to the objects. The proposed method evaluates the objects using evaluate functions which take the given priorities as parameters and decides the quality for each object using dynamic programming or a greedy algorithm. To show the usefulness of our method, we applied our method to MPEG-4-based application. As a result, we could control the quality within a reasonable time. We also found that we obtained different quality assignments when we used different evaluation functions, and that our method reflected the user requirements.

In this paper, we propose an innovative information delivery service on intelligent transport systems (ITS), which enables users to see their future vision delivered from users at further points along the route. This service requires special multicast and mobile routing schemes. We have developed a source mobility support multicast (SMM) technique that guarantees consecutive communication in high-speed mobile environments and minimizes the overhead in reconstructing multicast trees, which is caused by a source movement. SMM is based on a new concept where multicast tree is constructed over cellular IP network according to A. G. Valko (1999), in which a source point tree and a rendezvous point tree are combined into one multicast tree. SMM provides wide operability by partitioning the network and confining protocol uniqueness and topological constraints within the local access networks. This paper shows our design of SMM architecture and its detail protocols.

In this paper, we propose a new concept for information distribution on a ubiquitous network which we call information atmosphere. Information atmosphere consists of two types of data distribution: information vapor is an active user profile that enables distribution of user profile information to other accessible devices in a way similar to how materials evaporate and spread throughout an atmosphere. Information Solidification is the opposite function. Multiple devices sharing common information might have topics of common interest on the various users' devices. When new devices are connected to the environment, these devices detect suitable information through filtering, and then request it from the other devices on the local ubiquitous network. We describe this concept in detail and discuss an implementation of our concept: atmospheric content.

This paper describes a new network scheme that minimizes the consumption of network resources for on-demand streaming-video distribution through multicasting. In general, on-demand video distribution has been realized through unicasting. Asynchronous multicast techniques that reduce the load on the on-demand video server have been studied, but there has been little consideration of ways to reduce the network load. We have developed a statistical traffic-control theory based on asynchronous multicasting that can be used to adjust traffic on the trunk and branch links along the distribution tree to meet the network bandwidth design requirements to ensure QOS. In addition, we propose a dynamic bandwidth-allocation and traffic-adaptation algorithm that allows finite resources to be shared among different video deliveries by assigning the available bandwidth for each according to request rates. To show the implementability of these ideas, we consider their operation with protocols that autonomously construct a multicast tree and guarantee the QOS. We also discuss the effects of using this scheme based on a numerical analysis and simulation results regarding real traffic traces and the service-blocking rate.

Authors have carried out research and development concerning the next generation distributed multimedia platform in order for users to easily retrieve and view multimedia information distributed over a network. We also have focused on R&D of a dynamic hypermedia system (DHS) as a general-purposed platform independent of any application. The aim of our study was to classify content data in the system through the use of kansei-words. As a consequence, this report provides an experimental result here because of successful 4-50% achievement of classification.

In order to realize the general multimedia applications such as video-on-demand, multimedia conference and electronic museum, it is required to support variety of presentation which takes account of media synchronization. So far, we suggested a unified multimedia presentation protocol architecture considering a synchronization reference model to provide various synchronization functions depending on presentations in various applications. In this paper, we implemented a multimedia conference system which concurrently provides both live and stored presentations based on our proposed architecture and evaluated performance of lip synchronization method in the prototype system. As results, our synchronization method could provide effect and correct media presentation.

We propose a real-time contents edition system that allows the input of multiple audio-visual streams and simultaneous encoding into MPEG-4 video objects, editing, and delivery. This system is designed to enable the provision of content based on live video from multiple locations. Our system consists of editing, streaming, and display modules. Streaming and display modules can join/depart from the system while it is operating. To distribute high quality live video movies in different environments, content can also be encoded adaptively in various environments. In this paper, we present an overview of our real-time contents edition system. We also describe the algorithm used to decide whether inter-frame compression should be done frame-by-frame. The suitability of our algorithm was shown in an experimental implementation of the DV-MPEG transducer.

Hypermedia systems are very important as platforms in the future multimedia information network services. In order to provide more flexible and sophisticated multimedia presentation, it is desirable to simply and efficiently transmit various media data from the databases distributed over network and present them on the user station depending on scenario so as to semantically integrate into multimedia information objects. In this paper, a new hypermedia system which is based on object-oriented structure to perform two different temporal synchronization methods, "lip synchronization" and "scene synchronization" is introduced. Lip synchronization method performs, fine-grained temporal synchronization between continuous media, such as audio and video. On the other hand in scene synchronization, coarse-grained temporal relation between continuous media and discrete media, such as image, graphics or text is maintained depending on the presentation scenario. Furthermore, several media which are semantically related to each other are unified into a Media Group (MG) to simplify its media treatment. The MGs and their involved processing functions are encapsulated into a Media Object (MO) and easily controlled by message passing procedure. In this paper, implementation of the hypermedia model which performs scene synchronization function between discrete and continuous media in the MOs depending on the presentation scenario, and context switching function between each media presentation is precisely described. Finally "Electric Museum" as a prototype application of hypermedia systems is introduced to evaluate the suggested synchronization mechanism.

We propose a distributed multimedia system based on client-agent-server architecture for next-generation distributed multimedia general-purpose platform, as well as define advanced multimedia presentation models. In order to realize the platform, we have designed and developed Video-on-Demand and Multimedia-on-Demand systems as prototype system for the platform. In this paper we will discuss design methods that are parameter and primitive for Quality-of-Services (QoS), and implementation methods of multimedia manager and hypermedia manager that are presentation management functions.

We have engaged in research and technological development concerning integration of telecommunications and broadcasting, partially of the next generation Internet technology development over high-speed networks. As one of those projects, we developed the technology of transmitting the digital video and audio non-compression D1 format, the quality of which is equivalent to that of the professional use, recognized as a digital video transmission technology over IP. We report on the video-on-demand system over high-speed networks we designed using this technology.

Experimental and theoretical investigations of dispersion properties of magnetic particles (acicular gamma -Fe/sub 2/O/sub 3/) with an adsorbed epoxy-resin layer are presented. The adsorbed polymer amount was 20-110 mg/g and the adsorbed layer thickness was 6-22 nm, depending on the preparation conditions. Dispersion of gamma -Fe/sub 2/O/sub 3/ particles was evaluated by the sedimentation rate and surface roughness of the coated film. It was clarified that dispersion was improved with increasing adsorption, increasing solvent/epoxy-resin solubility, and decreasing gamma -Fe/sub 2/O/sub 3/ particle size. Interaction energy, consisting of magnetic attraction, van der Waals attraction, and steric repulsion of the adsorbed layer between two cylindrical magnetic particles, was calculated. The interaction energy curves, which vary with the distance between two particles, had primary minimum, maximum, and secondary minimum. The maximum energy and the secondary minimum energy were strongly related to dispersion stability. Experimental results are explained by the energy curve shapes. >

[1] In situ measurements of atmospheric methane (CH4) from the monitoring stations at Cape Ochi-ishi (latitude 43°10′N, longitude 145°30′E) during the period from July 1995 to July 2000 and at Hateruma Island (latitude 24°03′N, longitude 123°48′E) during the period from January 1996 to January 2000 are presented. At each station a fully automated gas chromatograph equipped with a flame ionization detector measures the CH4 mixing ratios at a frequency of more than 82 air samples per day. Over the above observation periods, average growth rates of CH4 mixing ratios were 4.5 parts per billion (ppb) yr−1 for Ochi-ishi and 4.7 ppb yr−1 for Hateruma, but there were considerable fluctuations in the instantaneous growth rate. The peak-to-peak amplitudes in the seasonal cycles determined from the smooth curve fits were 71 ppb for Ochi-ishi and 94 ppb for Hateruma. These seasonal amplitudes are larger than those at the sampling network sites of the National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory. Analysis of the back trajectories indicated that the air masses at both sites are transported from continental Asia in winter and from the Pacific Ocean in summer. Because there are strong CH4 sources in continental Asia but no strong sources in the Pacific Ocean, the seasonality of airflow patterns can explain the enhancement of the seasonal cycles. The significantly large seasonality, especially at Hateruma, is a result of air masses originating from a wide range of latitudes, the clear seasonality of airflows, and the steep latitudinal gradient of the CH4 mixing ratio.