A5064612688- Auction Theory and Applications
- Quantum Information and Cryptography
- Consumer Market Behavior and Pricing
- Quantum Computing Algorithms and Architecture
- Wireless Communication Networks Research
- Advanced Wireless Communication Techniques
- Optimization and Search Problems
- Quantum optics and atomic interactions
- Optical Network Technologies
- Railway Systems and Energy Efficiency
- Game Theory and Applications
- Traffic Prediction and Management Techniques
- Telecommunications and Broadcasting Technologies
- Millimeter-Wave Propagation and Modeling
- Interconnection Networks and Systems
- Supply Chain and Inventory Management
- Microstructure and Mechanical Properties of Steels
- Traffic control and management
- Transportation Planning and Optimization
- Semiconductor Lasers and Optical Devices
- Game Theory and Voting Systems
- Advanced MIMO Systems Optimization
- Advanced Computational Techniques and Applications
- Anomaly Detection Techniques and Applications
- Cloud Data Security Solutions
Nihon University
2002-2024
Gunma University
2024
University of Electro-Communications
2014-2023
NEC (Japan)
1998-2016
Tokyo University of Science
2013-2016
IHI Corporation (Czechia)
2010-2014
Tokyo Institute of Technology
2013
University of Tsukuba
2008-2012
IHI Corporation (Japan)
2002-2010
The University of Tokyo
1993-2009
A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into mesh-type network. GHz-clocked links enable us to demonstrate the world-first TV conferencing over distance of 45km. The includes commercial product for long-term stable operation, and application interface mobile phones. Detection an eavesdropper, rerouting path, relay via trusted nodes demonstrated this
An efficient and low-noise 1.244-GHz gating InGaAs singlephoton avalanche photodiode (SAPD) was developed for a high-speed quantum key distribution (QKD) system.An afterpulsing probability of 0.61% dark count per gate 0.71 ×10 -6 were obtained at detection efficiency 10.9% 1.55-µm photons.Furthermore, our SAPD successfully coped with high (≤ 25%) quite low noise 3% ≤ 25% efficiency) the same time.Its potential verified using actual QKD setups installed over metropolitan area network.
Tensile tests were conducted at 650°C on five different types of austenitic stainless steels varying in grain size. Each test was terminated strain from 5 to 15 % followed by sample preparation for EBSD. Crystal direction each point measured EBSD and misorientation determined Intra-granular Distortion, GOS (Grain Orientation Spread) KAM (Kernel Average Misorientation). Plastic found be correlated with the results obtained these methods, despite differences size material type. At a certain...
Secure networks composed of optical and quantum key distribution (QKD) are considered in this paper. A network layer structure is defined to focus on issues important with respect the QKD that controls links supplies a secure for message transmission. multiple-user can be constructed timing synchronization, sharing between indirectly connected nodes switched systems relays, management control volume generation supply response demand from nodes.
We discuss our estimates of the performance a superconducting single photon detector (SSPD) in high speed quantum key distribution (QKD) system.We find that at repetition operation reflections from readout circuit room temperature causes an afterpulse-like phenomenon, and drastically increases bit error rate (QBER).Such effects are not seen during low frequency operation.By using amplifier with small reflection coefficient S11, we succeed reducing phenomenon increasing secure rate.
Secret sharing schemes have recently been considered to apply for cloud computing in which many users distribute multiple data servers. However, when Shamir's (k, n) secret is applied systems, the amount of share increases more than n times secret. Therefore, this paper we propose a new scheme that can reduce different from Ramp type sharing, suitable and prove it computationally secure.
Virtual Machine(VM)-based flexible capacity management is an effective scheme to reduce total power consumption in the data centers. However, there remain following issues, trade-off between power-saving and user experience, decision on VM packing plans within a feasible calculation time, collision avoidance for multiple live migration processes. In order resolve these we propose two algorithms, matching-based (MBA) greedy-type heuristic (GREEDY). MBA enables decide optimal plan polynomial...
Positional MEDLINE (PosMed; http://biolod.org/PosMed) is a powerful Semantic Web Association Study engine that ranks biomedical resources such as genes, metabolites, diseases and drugs, based on the statistical significance of associations between user-specified phenotypic keywords connected directly or inferentially through biological databases MEDLINE, OMIM, pathways, co-expressions, molecular interactions ontology terms. Since 2005, PosMed has long been used for in silico positional...
We propose a new generation mobile communication system that can realize 100 Mbps carrier bit rate under high mobility environment and access the IP network easily. The is based on dynamic parameter controlled orthogonal frequency time division multiple (DPC-OF/TDMA) in which users share "slots" use certain number of subcarriers OFDM symbols. To slots, stations packet-reservation-based protocol: packet reservation time-slotted (PR-DSMA). In addition, to avoid cochannel interference from...
Debugging techniques and tools that draw on both the high-level concepts (defined as functions) used in formal specifications abstraction information-hiding constructs modern languages are described. The technique is based two components. One a novel specification language with support tools. Ada programs specified authors created called Anna. Their tool set to check program's runtime behavior for consistency Anna specifications. other uses find missing by comparing program prototypes test...
A novel secure communication network with quantum key distribution in a metropolitan area is reported. Different QKD schemes are integrated to demonstrate TV conferencing over distance 45km, stable long-term operation, and application mobile phones.
The effect of alloying to TiPd and TiPt on phase transformation temperature, equilibria, shape recovery were investigated for base high-temperature memory alloys. Ru, Ir, Co Zr chosen additional elements was found as the most effective element improve TiPt.
A sensor network system has been developed for tracking people's locations in workplaces as part of a ubiquitous providing context-aware services daily activities. Since the installation such is desired any place within its target domain with few limitations, it must operate by battery relatively long time, e.g., one month. To satisfy this requirement, we designed battery-operated node based on ZigBee technology and extended operation period developing flexible sleep control protocol...
In this paper, we propose an augmented reality (AR) system with a laser projection device as hands-on display at science museum. The AR provides virtual information, which learners can control for visual explanation about exhibited item. Learners develop their knowledge and understanding through the without any modification to item and/or existing displayed explanation. We conducted experiment using system, child visitors Gamagori Museum of Earth, Life Sea. systems should meet following...
This paper introduces robust optimization models for minimization of the network congestion ratio that can handle fluctuation in traffic demands between nodes. The simplest and widely used model to minimize ratio, called pipe model, is based on precisely specified demands. However, practice, operators are often unable estimate exact as they fluctuate due unpredictable factors. To overcome this weakness, we apply problem minimizing ratio. First, review existing counterparts certain...
Computerized interlocking systems have been studied for many years. Available mainly are centralized control systems. The great progress of distributed technology and intelligent terminals make it possible developing distribute system. In this research, a system its logic put forward. As the most important property system, safety has verified by using Petri net. result shows that new is safe correct
A packet/cell-based optical switch-fabric demonstrator has been successfully developed that is upgradable to 2.56 Tb/s throughput. The number of components in a 256/spl times/256 dramatically reduced one-eighth conventional switch-fabric.
We investigated the characteristics of shared keys obtained through quantum key distribution (QKD) from viewpoint application in cipher communication. demonstrated that at each stage QKD satisfy criteria determined by a standardized randomness test physically compensating for degrading factors. also examined increase error rate produced privacy amplification, and succeeded suppressing applying new amplification scheme, which yielded sufficiently low final keys. These investigations showed...
This paper describes offset optimization for the fluctuations of traffic flow using a genetic algorithm (GA). An offset, which is target signal control parameters this study, difficult to optimize because its variety combinations. Traffic GAs has been investigated in previous studies, most focused on without considering flow. In practical situation, rate changes as time passes, so that these required. As case an urban route city Chubu region Japan, with twenty-one signalized intersections,...
Abstract Recently it has become a common practice to construct 3D coreflooding simulation model interpret water displacement experiments conducted under X-ray CT scanning. The unknown grid block parameters i.e. kro/krw and Pc curves are required be optimized get reasonable matching with experimental data such as changes of saturation. In order evaluate the process efficiently new automated history-matching program been developed. This applies Genetic Algorithm optimize several coefficients...
A secure communication network with novel quantum key distribution systems in a metropolitan area (very center of Tokyo) is reported. Different QKD schemes are integrated to demonstrate relay for TV conferencing over distance 45 km, stable long-term operation.