Robust position control of ultrasonic motor using VSS observer

Intrinsic properties of ultrasonic motor (high torque for low speed, high static torque, compact in size, etc.) offer great advantages for industrial applications. However, when load torque is applied, dead-zone occurs in control input. Therefore, sliding mode controller, which is a nonlinear controller, is adopted for ultrasonic motor. The state quantities, such as acceleration, speed, and position are needed to apply the sliding mode controller for position control. However, rotary encoder causes quantization errors in the speed information. This paper presents a robust position control method for ultrasonic motor by using Variable Structure System(VSS) observer. The state variables for sliding mode controller are estimated by the VSS observer. Besides, a small, low cost, and good response sliding mode controller is designed in this paper by using a micro computer that is essential in embedded system for the developments of industrial equipments. The effectiveness of the proposed method is verified by experimental results

How do socio-ecological factors shape culture? Understanding the process of micro-macro interactions

Socio-ecological environments produce certain psychological functions. that are adaptive for survival in each environment. Past evidence suggests that interdependence-related psychological features are prevalent in East Asian cultures partly due to the history of ‘rice-crop farming’ (versus herding) in those areas. However, it is unclear how and why certain functional behaviors required by the socio-ecological environment are sublimated to become cultural values, which are then transmitted and shared among people. In this paper, we conceptually review the works examining various macro sharing processes for cultural values, and focus on the use of multilevel analysis in elucidating the effect of both macro and individual level factors. Uchida et al.’s study (2019) suggests that collective activities at the macro level (community-level), which is required by a certain socio-ecological environment, promote interdependence not only among farmers but also non-farmers. The multilevel processes of how psychological characteristics are construed by macro factors will be discussed

Frequency Control by Decentralized Controllable Heating Loads with H∞ controller

Many isolated small power systems are powered by diesel generators, which results in greater operating costs than interconnected large grids. It is therefore desirable to integrate renewable energy sources such as wind power into these small grids. However, due to the fluctuating power generation from renewable energy sources, frequency deviations of power systems become problematic. Distributed intelligent load control can be used to significantly increase renewable energy penetration and cut diesel fuel consumption. This paper presents a methodology for grid frequency control by electric water heaters as controllable loads. This system consists of diesel generator, wind farm, and loads. By applying a power consumption controller adopted from H∞control theory, grid frequency deviation is maintained around rated value. In order to verify the effectiveness of the proposed system, MATLAB/Simulink is used for simulations

Robust position control of ultrasonic motor considering dead-zone

Intrinsic properties of ultrasonic motor (high torque for low speed, high static torque, compact in size, etc.) offer great advantages for industrial applications. However, when load torque is applied, dead-zone occurs in the control input. Therefore, a nonlinear controller, which considers dead-zone, is adopted for ultrasonic motor. The state quantities, such as acceleration, speed, and position are needed to apply the nonlinear controller for position control. However, rotary encoder causes quantization errors in the speed information. This paper presents a robust position control method for ultrasonic motor considering dead-zone. The state variables for nonlinear controller are estimated by a Variable Structure System (VSS) observer. Besides, a small, low cost, and good response nonlinear controller is designed by using a micro computer that is essential in embedded system for the developments of industrial equipments. Effectiveness of the proposed method is verified by the experimental results

Venture into Cross-Cultural Psychology

A peer-reviewed book based on presentations at the XXIII Congress of the International Association for Cross-Cultural Psychology, 2016, Nagoya, Japan. (c) 2018, International Association for Cross-Cultural Psychologyhttps://scholarworks.gvsu.edu/iaccp_proceedings/1001/thumbnail.jp

Improving bonding strength by non-thermal atmospheric pressure plasma-assisted technology for A5052/PEEK direct joining

The direct bonding of A5052 aluminum (Al) alloy to the engineering polymer poly(ether ether ketone) (PEEK) using an atmospheric pressure plasma-assisted process was demonstrated. The effect of plasma irradiation on the bonding surface of metal resin on the bonding strength following thermal press fitting method was investigated. Specimens bonded by plasma irradiation on the PEEK surface only showed a high tensile shear stress of 15.5 MPa. With increasing plasma irradiation time, the bond strength of the samples bonded to the PEEK surface by plasma irradiation increased. The increase in the bond strength between metals and polymers following direct bonding is caused by the addition of oxygen functional groups on the polymer. In contrast, specimens in which only the Al was exposed to the plasma showed a decrease in bond strength compared with unirradiated samples. This reduction in bond strength is attributed to the forming magnesium oxide, which forms in the early stages of participation due to plasma irradiation.The version of record of this article, first published in International Journal of Advanced Manufacturing Technology, is available online at Publisher’s website: https://doi.org/10.1007/s00170-023-12747-

Mechanical interaction between neighboring muscles in human upper limb: evidence for epimuscular myofascial force transmission in humans

To confirm the existence of epimuscular myofascial force transmission in humans, this study examined if manipulating joint angle to stretch the muscle can alter the shear modulus of a resting adjacent muscle, and whether there are regional differences in this response. The biceps brachii (BB: manipulated muscle) and the brachialis (BRA: resting adjacent muscle) were deemed suitable for this study because they are neighboring, yet have independent tendons that insert onto different bones. In order to manipulate the muscle length of BB only, the forearm was passively set at supination, neutral, and pronation positions. For thirteen healthy young adult men, the shear modulus of BB and BRA was measured with shear-wave elastography at proximal and distal muscle regions for each forearm position and with the elbow joint angle at either 100° or 160°. At both muscle regions and both elbow positions, BB shear modulus increased as the forearm was rotated from a supinated to pronated position. Conversely, BRA shear modulus decreased as function of forearm position. The effect of forearm position on shear modulus was most pronounced in the distal muscle region when the elbow was at 160°. The observed alteration of shear modulus of the resting adjacent muscle indicates that epimuscular myofascial force transmission is present in the human upper limb. Consistent with this assertion, we found that the effect of muscle length on shear modulus in both muscles was region-dependent. Our results also suggest that epimuscular myofascial force transmission may be facilitated at stretched muscle lengths

Natural polyphenols convert proteins into histone-binding ligands

peer reviewedAntioxidants are sensitive to oxidation and are immediately converted into their oxidized forms that can react with proteins. We have recently found that proteins incubated with oxidized vitamin C (dehydroascorbate) gain a new function as a histone-binding ligand. This finding led us to predict that antioxidants, through conversion to their oxidized forms, may generally have similar functions. In the present study, we identified several natural polyphenols as a source of histone ligands and characterized the mechanism for the interaction of protein-bound polyphenols with histone. Through screening of 25 plant-derived polyphenols by assessing their ability to convert bovine serum albumin into histone ligands, we identified seven polyphenols, including (-)-epigallocatechin-3-O-gallate (EGCG). Additionally, we found that the histone tail domain, which is a highly charged and conformationally flexible region, is involved in the interaction with the polyphenol-modified proteins. Further mechanistic studies showed the involvement of a complex heterogeneous group of the polyphenol-derived compounds bound to proteins as histone-binding elements. We also determined that the interaction of polyphenol-modified proteins with histones formed aggregates and exerted a protective effect against histone-mediated cytotoxicity toward endothelial cells. These findings demonstrated that histones are one of the major targets of polyphenol-modified proteins and provide important insights into the chemoprotective functions of dietary polyphenols