著者

Takaharu Yamanaka Takanori Iwai Ryogo Kubo

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Communications Express (ISSN:21870136)

巻号頁・発行日

vol.10, no.6, pp.301-306, 2021-06-01 (Released:2021-06-01)

参考文献数

8

---

In networked control systems, the quality of performance (QoP), such as in terms of consistent tracking errors, must be maintained at a constant level. A QoP-aware sleep mechanism in network interfaces can reduce the amount of traffic or the communication rate while maintaining the QoP. However, in a QoP-aware sleep mechanism with a fixed sleep period, the sleep period cannot be entered effectively when the length of the steady-state period is changed; e.g., when the command frequency is changed. This study proposes a variable sleep period control method to reduce the communication rate while adapting to the tracking error. The simulations confirm that, when compared to methods with a fixed sleep period, the proposed method reduces the communication rate regardless of the command frequency.

著者

Ryogo Kubo Mario Yokota Sadao Nakajima

出版者

一般社団法人 日本物理学会

雑誌

Journal of the Physical Society of Japan (ISSN:00319015)

巻号頁・発行日

vol.12, no.11, pp.1203-1211, 1957-11-05 (Released:2007-06-01)

参考文献数

23

被引用文献数

573

---

The possibility is examined to give rigorous expressions for kinetic coefficients such as heat conductivity, diffusion constant, thermoelectric power and so on which relate the flow of a certain kind to the generalized forces of thermal nature. We take here as the fundamental assumption Onsager’s assumption that the average regression of spontaneous fluctuation of macroscopic variables follows the macroscopic physical laws. The kinetic coefficient Gjl appearing in the phenomenological equation, \dotαj=∑Gjl(∂S⁄∂αl) is shown then to be expressed asGjl=(kβ)−1∫0∞dτ∫0β<\dotαl(−ihλ)\dotαj(τ)>dλwhere k is the Boltzmann constant and β=1⁄kT. This is the same type of formula as we have for kinetic coefficients for mechanical disturbances (Kubo, J. Phys. Soc. 12 (1957) 570). The theory is illustrated for the example of electronic transport phenomena.