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Ogino T.,Okinawa National College of Technology
Advances in Intelligent Systems and Computing | Year: 2015

The network intrusion is becoming a big threat for a lot of companies, organization and so on. Recent intrusions are becoming more clever and difficult to detect. Many of today's intrusion detection systems are based on signature-based. They have good performance for known attacks, but theoretically they are not able to detect unknown attacks. On the other hand, an anomaly detection system can detect unknown attacks and is getting focus recently. In this paper, we study the effectiveness and the performance experiments of one of the major anomaly detection scales, LOF, on distributed online machine learning framework, Jubatus. © Springer International Publishing Switzerland 2015.

Makishi O.,Okinawa National College of Technology | Honda H.,Kyushu University
International Journal of Heat and Mass Transfer | Year: 2012

Previously proposed theories of the minimum-heat-flux-point (MHF-point) condition were examined using available experimental data obtained from the immersion cooling of spheres in water. The sphere diameter ranged from 9.5 to 30 mm and the liquid subcooling from 0 to 85 K. The limiting liquid superheat predicted by the Lienhard equation was compared with the liquid-solid interface superheat at the instant of liquid-solid contact at the MHF-point. The results showed that the liquid-solid interface superheat was not limited by the limiting liquid superheat and its value was connected with the collapse mode of vapor film. The collapse mode was a coherent collapse at a low interface superheat and the mode changed to a propagative collapse as the interface superheat increased. The critical vapor film thickness obtained from the linear stability analysis of vapor film was compared with the calculated value of average vapor film thickness at the MHF-point. For all data, the ratio of the average vapor film thickness to the critical vapor film thickness was correlated well as a function of liquid subcooling. The ratio decreased with increasing liquid subcooling and tended to about 0.8 to 1 depending on the experiments. This indicated that the MHF-point at a high liquid subcooling was determined by the critical vapor film thickness. A physical consideration was given to the effect of liquid-solid contact that occurred in the film boiling region on the calculated value of the vapor film thickness and the stability of vapor film. © 2012 Elsevier Ltd. All rights reserved.

Iguchi A.,Okinawa National College of Technology
Current Bioinformatics | Year: 2014

Many aspects of the reproductive biology of scleractinian corals remain unknown. External fertilisation during broadcast spawning events generates the potential for interspecific hybridisation, yet whilst efficient cross-fertilisation often occurs in vitro and species boundaries are blurred due to introgression, in nature hybridisation happens rarely even between sympatric and highly cross-fertile species. One potential explanation of the discrepancy between the observed and potential level of hybridisation is temporal partitioning. An essential first step towards resolving this apparent paradox is an understanding of the molecular basis of fertilisation premise that these may provide insight into the mechanisms dictating fertilisation in spawning corals. This leads to propose that interactions involving integrins, ADAM family proteins and modifiers/co-receptors may underlie gamete interactions in corals. The identification of fast-evolving genes such as ADAMs also promises to provide candidates for roles in coral fertilisation. Overall in this review I describe how new genomic information can shed light on the molecular basis of coral fertilisation and this will help progress our understanding of the reproductive systems in this keystone group of reef-building organisms. © 2014 Bentham Science Publishers.

Sugimoto K.,Okinawa National College of Technology
Proceedings - Frontiers in Education Conference, FIE | Year: 2015

In this paper, the effectiveness of our approach for engineering education at an early stage is presented. It is designed for 15 or 16-year-old students who have just begun to take lectures for a specific specialized field of engineering in our college of technology. Here, how to encourage their learning motivation for various fields of engineering becomes important. Therefore, our program was designed by focusing on skills for communication, writing reports and making presentation through an engineering education practice as a project based learning by 4 or 5 students a group. The decision was made through discussion by the group unit. In order to check presence of the difference between generations, the investigation with a program of the same contents has been carried out for three years. By analyzing the answer to the questionnaire and impression in free form answering from 160 students in total every year for inspection of effectiveness, we conclude that our approach is effective not only for the enhancement of student's learning motivation in the engineering education program but their recognition for importance of the skill acquirement was confirmed. © 2014 IEEE.

Chinen K.,Okinawa National College of Technology
Technical Digest - 2012 17th Opto-Electronics and Communications Conference, OECC 2012 | Year: 2012

The dominant cause of the increase of the Relative Constellation Error (RCE) when the DFB-LD is largely modulated in the WiMAX-RoF is not the current clipping around the threshold current but the optical multi-mode oscillation. © 2012 IEEE.

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