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Khumlumlert T.,Naresuan University | Kanjanapa W.,Naresuan University | Aiemsa-Ad N.,Rajanagarindra Rajabhat University
Advanced Science Letters | Year: 2017

Propagation of the solar particles and its interplanetary environment of an impulsive flare on November 3, 2013 and gradual flares on August 9, 2011 were studied. The impulsive flare and the gradual flare had the X-ray classes of M5.0 and X6.9 at the position on the Sun of S12W16 and N17W69, with the solar wind speed 387.8 km/s. and 600 km/s respectively. The shock wave after the explosion from the gradual flare was found. The propagation of the solar particles were simulated by the Ruffolo 1995, 1998 transport equation and solved by finite different method. The injection duration was estimated by the curve-fitting technique of piecewise-linear least square with the simulated results and the data from spacecraft. The solar particles with high energy transported along the interplanetary magnetic field line longer than that of the low energy solar particles. The injection duration of solar particles with high energy from the Sun to the Earth is shorter than that of the low energy. Shock wave affected on the particle acceleration after explosion in the interplanetary medium, corresponding to the long injection time. The violent explosion of these solar flares didn’t affect on the Earth’s magnetic field, because their Kp-index values were less <3. © 2017 American Scientific Publishers All rights reserved.


Pukkasenung P.,Rajanagarindra Rajabhat University | Pukkasenung P.,Mahanakorn University of Technology | Chokngamwong R.,Mahanakorn University of Technology
Lecture Notes in Electrical Engineering | Year: 2016

Mobile phones are getting smarter and people have been using them for many different proposes. Recently, more and more people have begun using their mobile phones as a method of payment for online shopping and banking. Mobile payments have become easier than ever. Present security issues of mobile payments, however, still require improvement. This paper aims to summarize the idea of mobile payments and analyze the research of existing secure mobile payment protocols by using MPPS (Mobile Payment Protocol Security) framework. As a result, this paper will give researchers tools to standardize current protocol and share new developments. © Springer Science+Business Media Singapore 2016.


Khancome C.,Rajanagarindra Rajabhat University | Boonjing V.,King Monkuts Institute of Technology at Ladkrabang | Chanvarasuth P.,Thammasat University
Proceedings of the 2013 10th International Conference on Information Technology: New Generations, ITNG 2013 | Year: 2013

Multiple string pattern matching is one of many approaches to simultaneously search occurrences of a large number of patterns in a given text. In this paper, a new solution to this problem is presented by using two-hashing tables to minimize attempting times. This solution, called Two-Hashing Table Multiple String Patterns Matching Algorithm (Two-HT-MSPMA), is suitable for very long length of minimum pattern length. Its time complexity is more efficient than classic algorithms. Empirical results showed that its attempting times were less than of traditional algorithms. © 2013 IEEE.


Jettanasen C.,King Mongkut's University of Technology Thonburi | Thongsuk S.,Rajanagarindra Rajabhat University
2013 International Conference on Electrical Machines and Systems, ICEMS 2013 | Year: 2013

This paper focuses on attenuation of high-frequency (HF) electromagnetic noise commonly caused by high-frequency switching devices. A full bridge single-phase SPWM inverter switched by IGBT is employed to drive an ac motor, which is usually widely used in many domestic and industrial applications. More the switching frequency is high more electromagnetic interference (EMI) is considerably generated. That is why an EMI reduction method is necessary to be applied in the system. The proposed method herein is passive low-pass EMI filtering that can reduce noise in machine drive in order to prevent device damage and improve the efficiency of overall motor drive system. © 2013 IEEE.


Chongsri K.,Rajanagarindra Rajabhat University | Pecharapa W.,King Mongkut's University of Technology Thonburi | Pecharapa W.,ThEP Center
Energy Procedia | Year: 2014

Aluminum doped zinc oxide (AZO) thin films were studied as an UV photodetector devices. The AZO thin films were prepared on FTO substrates by spin coating technique. All samples exhibit prominent optical absorption edge with high optical transparency in visible range and significant blue-shift in optical band gap with increasing Al composition. The photoilluminated current increases linearly with increasing bias voltage reflecting ohmic contact behavior. The detectors have excellent ultraviolet response in wavelength region of 250-380 nm suggesting that tunable wavelength response can be obtained by increasing Al composition. © 2014 Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.


Surapanich N.,Rajanagarindra Rajabhat University | Chaisuwan P.,Suranaree University of Technology | Kuhakarn C.,Mahidol University | Reutrakul V.,Mahidol University
Synlett | Year: 2016

A formal [3+2] cycloaddition of triphenylcarbenium tetrafluoroborate with structurally different styrene derivatives has been developed. A combination of benzophenone and Et3N is key for promoting a formal [3+2] cycloaddition of triphenylcarbenium tetrafluoroborate with styrenes affording 1,1-diphenyl-3-arylindanes in moderate to good yields. The reaction mechanism of this transformation is also discussed. Copyright © 2016, Georg Thieme Verlag. All rights reserved.


PubMed | Mahidol University, Umeå University, Rajanagarindra Rajabhat University and University of Heidelberg
Type: Journal Article | Journal: PloS one | Year: 2016

Dengue is an important neglected tropical disease, with more than half of the worlds population living in dengue endemic areas. Good understanding of dengue transmission sites is a critical factor to implement effective vector control measures.A cohort of 1,811 students from 10 schools in rural, semi-rural and semi-urban Thailand participated in this study. Seroconversion data and location of participants residences and schools were recorded to determine spatial patterns of dengue infections. Blood samples were taken to confirm dengue infections in participants at the beginning and the end of school term. Entomological factors included a survey of adult mosquito density using a portable vacuum aspirator during the school term and a follow up survey of breeding sites of Aedes vectors in schools after the school term. Clustering analyses were performed to detect spatial aggregation of dengue infections among participants.A total of 57 dengue seroconversions were detected among the 1,655 participants who provided paired blood samples. Of the 57 confirmed dengue infections, 23 (40.0%) occurred in students from 6 (6.8%) of the 88 classrooms in 10 schools. Dengue infections did not show significant clustering by residential location in the study area. During the school term, a total of 66 Aedes aegypti mosquitoes were identified from the 278 mosquitoes caught in 50 classrooms of the 10 schools. In a follow-up survey of breeding sites, 484 out of 2,399 water containers surveyed (20.2%) were identified as active mosquito breeding sites.Our findings suggest that dengue infections were clustered among schools and among classrooms within schools. The schools studied were found to contain a large number of different types of breeding sites. Aedes vector densities in schools were correlated with dengue infections and breeding sites in those schools. Given that only a small proportion of breeding sites in the schools were subjected to vector control measures (11%), this study emphasizes the urgent need to implement vector control strategies at schools, while maintaining efforts at the household level.


Lin A.Y.,University of Sheffield | Parinyavuttichai N.,Rajanagarindra Rajabhat University
Australasian Journal of Information Systems | Year: 2015

While the number of substantive investments in IS projects continues to grow, the number of failing projects also continues to increase at an alarming rate. Both the academic and industry literature suggests that inadequate attention to risk and its management continues to be a key factor in project failure. The typical approach taken is to identify and map potential risks, to act as a planning and diagnostic tool, and to prepare a contingency plan has been a factor- based approach. While it remains a valuable tool for mapping anticipated risks the factor- based approach is less effective when viewing project risks as emergent phenomena that un- fold during the course of the project, and require ongoing attention and risk management. In- formed by a case study of a failing university IS development project, this paper focuses on the phenomenon of risk escalation. The case findings suggest that rather than being defined ahead of the project, some project risks may emerge during the project as a consequence of escalation factors that were both antecedent to and a consequence of actual risk management decisions. The article concludes with suggestions as to how project managers can better man-age the emergent rather than static nature of risk phenomena. © 2015 Lin & Parinyavuttichai.


Pukkasenunk P.,Rajanagarindra Rajabhat University | Sukkasem S.,Rajanagarindra Rajabhat University
Proceedings - IEEE 30th International Conference on Advanced Information Networking and Applications Workshops, WAINA 2016 | Year: 2016

This paper presents a secure mobile bill payment application. It is developed from a concept of a lightweight, agent-based, secure mobile payment protocol[1]. This aspect focuses on measuring the efficiency of the application while processing on a mobile phone. We compared the performance of the proposed method and the traditional method by using three indicators of performance. These include, memory usage, time usage, and power consumption. The results revealed that the new method delivered better performance than the traditional. So, it is suitable for the lifestyle of users in 21st century because it is convenient and user-friendly. © 2016 IEEE.


Parinyavuttichai N.,Rajanagarindra Rajabhat University | Lin A.,University of Sheffield
19th Americas Conference on Information Systems, AMCIS 2013 - Hyperconnected World: Anything, Anywhere, Anytime | Year: 2013

Information Systems project failure has retained its preeminent position as one of the most important research streams in the past decades. Many studies attempt to understand what causes project failure as it is known as the first and most important step to effectively manage projects and avoid project failure. One of the most important reasons causing failure cited in IS literature and trade reports is project escalation. The phenomenon of project escalation has generally been examined from traditional perspectives and little is known about the phenomenon from an IS risk viewpoint. A qualitative case study of an IS project in Thailand is then used to illustrate the nature of project escalation and explain the relationships between project escalation and IS risks. The results of this study extend the existing body of knowledge of project escalation and describe the dynamic nature of project escalation from a nontraditional point of view. © (2013) by the AIS/ICIS Administrative Office All rights reserved.

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