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Nitrated Polymeric carbohydrates are not very pure when used, as their physical constants are neither sharp nor unique for positive identification purposes. The ingredients of explosives are so numerous and it was considered beyond the scope of this investigation to include them. 相似文献
3.
In light of current calls by medical professionals to confront the global issue of obesity and related illnesses, we developed a mobile application called STEP UP that monitors physical activity and provides data that can be easily shared within a social network. We then conducted an exploratory, theoretical study based on the theory of reasoned action (TRA) followed by an experimental trial and user study. The purpose of the studies was to explore the effect of persuasive technology on physical activity behavior and to investigate its effectiveness in motivating users to use the technology to be more physically active. The application was found to have a positive effect on the participants and their level of physical activity. They enjoyed using the application and were motivated to walk more, especially when enabled to share their step counts with their friends. The social component of the application clearly enhanced users’ walking experience, as the atmosphere of friendly competition motivated them to walk more. Based on user responses, we conclude that a further enhanced application that includes chat functionality may be even more successful in supporting increased physical activity and thus healthier lifestyle. 相似文献
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Hussein Khalid F. A. Helmy Asmaa O. Mohra Ashraf S. 《Wireless Personal Communications》2022,126(1):871-893
Wireless Personal Communications - This paper proposes a novel design of a software-defined matched filter (MF) for digital receivers of synthetic aperture radar (SAR). The block diagram of the... 相似文献
6.
Ahmed F. Sayed Fathy M. Mustafa Ashraf A.M. Khalaf Moustafa H. Aly 《International Journal of Communication Systems》2020,33(14)
In this paper, a postdispersion compensation unit is proposed leading to a better performance for the optical communication systems. This unit utilizes a chirped fiber Bragg grating (CFBG). For enhanced performance of the CFBG, a proper apodization function is chosen to improve the quality factor (Q‐factor) and the bit error rate (BER) of the system. A 110‐km wavelength division multiplexing (WDM) optical link is investigated. The system performance is evaluated through its Q‐factor, eye diagram, and BER showing best performance when using the Hamming apodization function. 相似文献
7.
Remika Ngangbam Ashraf Hossain Alok Shukla 《International Journal of Electronics》2020,107(3):390-402
ABSTRACTWireless sensor networks (WSNs) play a vital role in present-day world, which are being used in different types of applications and occupy an important part in networking domain. The main objective of WSNs is to sense and collect the information from a given area of interest and provide the gathered data to the sink. WSN comprises of number of sensor nodes with batteries of limited energy for communication and computational activities, which are not possible to recharge the batteries after their deployment in the region of interest. Therefore, saving battery energy and utilising the limited power to the optimum level for extending network lifetime became the main factor of WSN. Hence, optimum cluster head (CH) selection will make the network to support longer lifetime and balanced energy consumption during its lifetime. Our proposed protocol selects the optimum CH and found out to be more efficient than the existing low energy adaptive clustering hierarchy. The simulated output shows better network lifetime and in some other performance metric. 相似文献
8.
Anwar Ghani Khwaja Mansoor Shahid Mehmood Shehzad Ashraf Chaudhry Arif Ur Rahman Malik Najmus Saqib 《International Journal of Communication Systems》2019,32(16)
Wireless sensor networks (WSN) consist of hundreds of miniature sensor nodes to sense various events in the surrounding environment and report back to the base station. Sensor networks are at the base of internet of things (IoT) and smart computing applications where a function is performed as a result of sensed event or information. However, in resource‐limited WSN authenticating a remote user is a vital security concern. Recently, researchers put forth various authentication protocols to address different security issues. Gope et al presented a protocol claiming resistance against known attacks. A thorough analysis of their protocol shows that it is vulnerable to user traceability, stolen verifier, and denial of service (DoS) attacks. In this article, an enhanced symmetric key‐based authentication protocol for IoT‐based WSN has been presented. The proposed protocol has the ability to counter user traceability, stolen verifier, and DoS attacks. Furthermore, the proposed protocol has been simulated and verified using Proverif and BAN logic. The proposed protocol has the same communication cost as the baseline protocol; however, in computation cost, it has 52.63% efficiency as compared with the baseline protocol. 相似文献
9.
Masugi Inoue Khaled Mahmud Homare Murakami Mikio Hasegawa Hiroyuki Morikawa 《Wireless Personal Communications》2005,35(1-2):53-70
A context-based adaptive communication system is introduced for use in heterogeneous networks. Context includes the user's
presence, location, available network interfaces, network availability, network priority, communication status, terminal features,
and installed applications. An experimental system was developed to clarify the feasibility of using context information to
flexibly control networks and applications. The system operates on a seamless networking platform we developed for heterogeneous
networks. By using contexts, the system can inform the caller and callee of applications they can access, which are available
through the network before communication occurs. Changes in contexts can switch an on-going application to another during
actual communication. These functions provide unprecedented styles of communication. A business scenario for a seamless networking
provider is also presented.
Dr. Morikawa has also been in charge of NICT's Mobile Networking Group.
Masugi Inoue received his B.E. from Kyoto University in 1992 and his M.E. and D.E. from the University of Tokyo in 1994 and 1997, all
in the field of Electrical Engineering. He is currently a senior researcher at the Yokosuka Radio Communications Research
Center under the National Institute of Information and Communications Technology (NICT), Japan, and has been engaged in R&D
on ultrahigh-speed WLANs and mobile networking. He joined the Communications Research Laboratory (CRL) of the Ministry of
Posts and Telecommunications, Japan, in 1997, which was reorganized as NICT in April 2004. He was a visiting researcher at
Polytechnic University in Brooklyn, New York in 2000.
Khaled Mahmud received his B.Sc. (Eng.) in Electrical and Electronics Engineering from the Bangladesh University of Engineering and Technology
in Dhaka in 1991. He received his M.E. and Ph.D. in the same field from Shizuoka University in Japan, in 1997 and 2000, respectively.
He was a research fellow at NICT, Japan, from 2000 to 2004. He is currently an Assistant Professor in the Department of Computer
Science and Engineering at North South University, Bangladesh. His research interests include modulation-demodulation techniques,
software radio, mobile communication systems, wireless Internet, and IP mobility technologies.
Homare Murakami received his B.E. and M.E. in Electronic Engineering from Hokkaido University in 1997 and 1999. In 2004, he received the
Young Investigators Award from IEICE. He is currently a researcher at NICT's Mobile Networking Group. He is also an industrial
PhD student in Aalborg University since 2003. His interest areas are naming scheme, wireless TCP and new transport protocol,
IP mobility, fast handover method, and location management.
Mikio Hasegawa received his B. Eng, M. Eng., and Dr. Eng. in 1995, 1997, and 2000 from Science University of Tokyo. From 1997 to 2000, he
was a Research Fellow of the Japan Society for the Promotion of Science (JSPS). He is currently a senior researcher in Mobile
Networking Group, National Institute of Information and Communications Technology, and a technical advisor in ChaosWare Inc.
His research interests include applications of chaotic dynamical theory, combinatorial optimization, mobile networks, and
ubiquitous computing.
Hiroyuki Morikawa received his B.E., M.E., and D.E. in Electrical Engineering from the University of Tokyo in 1987, 1989, and 1992. He is currently
an Associate Professor in the Department of Frontier Informatics at the University of Tokyo and is in charge of NICT's Mobile
Networking Group. His research interests are in the areas of computer networks, mobile computing/networks, ubiquitous computing,
and network services. He serves as Editor of Transactions of the IEICE and has been on the technical program committees of
IEEE/ACM conferences and workshops. He sits on numerous telecommunications advisory committees and frequently serves as a
consultant to the government. 相似文献
10.
Experimental studies have been carried out on hydrocarbon group analysis of commercial Arabian crude oil fractions corresponding to the true boiling point ranges or 200-400 ast;F, 400-500 *F 500-650 *F, 650-850 *F, and 850 *F-K The crude oils included Arab heavy (API* = 28·0), Arab medium (API* = 30·0), Arab light (API* = 33·3), and Arab Berry extra light (API* = 36*9). Waters Hydrocabon Group Analyzer (HGA) system interfaced with model 730 Data Module has been used to obtain the compositional analysis in terms of saturates, neutral aromatics, polar aromatics and asphaltcnes. 相似文献