Crystal Structure Transformation and Dielectric Properties of Polymer Composites Incorporating Zinc Oxide Nanorods

Zinc oxide (ZnO) nanorods were synthesized using a modified wet chemical method. Poly(vinylidene fluoride-co-hexafluoropropylene), P(VDF-HFP), nanocomposites with different ZnO nanorods loadings were prepared via a solution blend route. Field emission scanning electron microscopic (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) were used to investigate the structure and morphology of the nanocomposites. XRD and FTIR data indicate that the incorporation of ZnO nanorods promote the crystalline structure transformation of P(VDF-HFP). As the content of ZnO nanorods increases, the β phase structure increases while the α phase decreases. In addition, the dielectric properties of the P(VDF-HFP) and its composites were systematically studied

Subaru Imaging of Asymmetric Features in a Transitional Disk in Upper Scorpius

We report high-resolution (0.07 arcsec) near-infrared polarized intensity images of the circumstellar disk around the star 2MASS J16042165-2130284 obtained with HiCIAO mounted on the Subaru 8.2 m telescope. We present our $H$-band data, which clearly exhibits a resolved, face-on disk with a large inner hole for the first time at infrared wavelengths. We detect the centrosymmetric polarization pattern in the circumstellar material as has been observed in other disks. Elliptical fitting gives the semimajor axis, semiminor axis, and position angle (P.A.) of the disk as 63 AU, 62 AU, and -14 $^{\circ}$, respectively. The disk is asymmetric, with one dip located at P.A.s of $\sim85^{\circ}$. Our observed disk size agrees well with a previous study of dust and CO emission at submillimeter wavelength with Submillimeter Array. Hence, the near-infrared light is interpreted as scattered light reflected from the inner edge of the disk. Our observations also detect an elongated arc (50 AU) extending over the disk inner hole. It emanates at the inner edge of the western side of the disk, extending inward first, then curving to the northeast. We discuss the possibility that the inner hole, the dip, and the arc that we have observed may be related to the existence of unseen bodies within the disk.Comment: 21 pages, 3 figures, published 2012 November 7 by ApJL, typo correcte

べルンシュタイン文庫を彩る仏革命の世界

departmental bulletin pape

子どもの価値意識を生かした追究活動

論文departmental bulletin pape

Approaching Movement-Aware Satellite Selection Method for Low-Earth-Orbit Satellite Networks

In recent years, Low-Earth-Orbit (LEO) satellite networks, such as Starlink, have been advancing rapidly. However, it has been shown that Starlink may experience frequent variations in link quality due to handovers and other factors. Furthermore, since the communication process in Starlink is proprietary, only end-to-end verification has been conducted. The method used for satellite selection is still unclear. Therefore, this study simulates the current and future Starlink environments using the ns-3 LEO module and evaluates the effect of the satellite selection method on the communication performance in LEO satellite networks. We propose two satellite selection methods that lengthen communication time by considering the movement of available satellites. Simulation results demonstrate that the proposed methods effectively increase the communication time provided by the selected satellite. The evaluation results indicate that the connected satellite should be selected by considering both the satellite altitude and the application requirements.journal articl

Experimental Evaluation of Application Traffic Characteristics on WLANs in the IoT Era

Wireless LANs (WLANs) are mainly used as access networks in the Internet of Things (IoT) era, and the latest standard IEEE802.11ax requires WLANs to communicate with multiple stations simultaneously. As IoT devices proliferate, the number of stations connected to a WLAN will significantly increase, and thus WLANs will need to accommodate IoT traffic with new characteristics totally different from those of traditional traffic, such as rich content. Because our previous study showed that the performance of an IEEE802.11ax WLAN depends on the number of stations and traffic characteristics, a new traffic control scheme becomes essential for the coexistence of rich content and IoT traffic. Therefore, we investigated the traffic characteristics of IoT devices to clarify their differences. Based on these considerations, we concluded that a real-time traffic estimation and classification method is necessary for real-time traffic control on WLANs in the IoT era.The 15th International Conference on Intelligent Networking and Collaborative Systems (INCoS-2023), 6-8 September., 2023, Chiang Mai University, Thailandjournal articl

「うそをつく」の語彙史

application/pdfdepartmental bulletin pape

MPEG Frame Priority and Radio congestion-aware dynamic frame transmission control method

In recent years, wireless LANs have become widely adopted as a communication infrastructure. Wireless communication quality fluctuates due to factors like obstacles and coexisting communications, which in turn affect application quality. However, applications continue to send data without considering these fluctuations and wireless congestion, thereby further degrading application quality. Moreover, the physical/MAC layers transmit data uniformly regardless of its value to the application. As a result, the loss of high-value data can lead to a significant deterioration in application quality. In response to this issue, our research aims to mitigate application quality degradation and make efficient use of wireless resources by selecting and transmitting only the critical data to maintain application quality, based on the priority of the MPEG frames and the wireless congestion status.conference pape

Method for Transparent Transformation of Monolithic Programs into Microservices for Effective Use of Edge Resources

A lot of research has recently been conducted on edge computing. Since edge servers have relatively small computational resources, it is necessary to perform processing by utilizing the resources of multiple servers for effective resource utilization at each edge server. Conventional technologies for improving the efficiency of computational processing, such as the Message Passing Interface, often require the development of programs to optimize computational processing for dedicated execution environments and are thus unsuitable for edge environments where the server environment is diverse and the load status changes over time. Our research group has studied data processing at edge servers and proposed a method for performing data processing by repeating small processes and data transfers among multiple general-purpose servers. However, we have not developed a concrete method for partitioning a program and combining the parts into a set of small processes. In this paper, we propose a method for transparently creating microservices by automatically partitioning a monolithic program into small processes, which can be executed and transfer data among themselves, without considering the optimization of the processes during program development. A sample program is partitioned using the proposed method to demonstrate that the partitioning of functions and establishment of flexible communication connections among the partitioned functions can be realized.journal articl

A Transparent Method of Microservices for Monolithic Programs toward Effective Utilization of Edge Resources

There has recently been a lot of research and development on edge computing technology. As the number of servers in an edge network is limited, efficient management of computational resource utilization is important. To address the issues, our research group has been developing a method that partitions a program into small processes and executes each process on a different edge server to maximize edge resource utilization [1]. However, this research assumes that a program is developed as a set of small processes. We did not consider how to create specific that processes. In this study, to maximize the efficiency of resource utilization in edge networks, we propose a method for partitioning a single (monolithic) program into small processes (called unit processes) and providing them as microservices by embedding a communication function into each unit process.conference pape