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Sliding mode control can deal with nonlinearities of control systems and is robust. However, it has drawbacks, such as high control gain effect and control chattering. This paper proposes a method of nonlinear feedback control introducing fuzzy inference into sliding mode control. The fuzzy inference is introduced to treat nonlinearities of control systems and to reduce the control chattering. Furthermore, the stability of the system is discussed by the fuzzy stability theory based on Lyapunov's direct method. The proposed method is applied numerically to the stabilizing control of an electric power system as a nonlinear system and is shown to give a good control effect.

Adoption of magnetic levitation techniques for production lines of steel plates has many advantages such as simplification of machining processes and improvement in quality of products. However, conventional levitation [1] procedures have not solved the problem for thin steel plates of sideslipping caused by gravitational force. In this paper, the following idea is proposed in order to avoid sideslip: The gap length command between the steel plate and the electromagnet is corrected so as to levitate the plate horizontally. Various experiments are performed under the proposed control, in order to confirm the validity. Index Terms--Guide control, horizontal control, MAGLEV for thin steel plates.

To develop a rat T-cell-dependent antibody response (TDAR) model evaluating both primary and secondary antibody responses, keyhole limpet hemocyanin (KLH) was used to immunize rats twice during a 14-day course of study, a pattern closely linked to that of a short-term general toxicity study. Female rats of four representative strains (e.g., Sprague-Dawley, Wistar, Fischer, and Lewis) were immunized twice with intravenous administrations of KLH (300 µg/rat) on Days 5 and 9 during a 14-day treatment regimen with cyclophosphamide (CPA) at 1, 3, or 6 mg/kg/day. The primary and secondary immunizations of KLH markedly elevated serum anti-KLH IgM and IgG levels in all strains on Days 9 and 15. Remarkable higher levels of anti-KLH IgG (≈ 1000 µg/ml) were noted in all strains, which were more than 4-times compared with those of anti-KLH IgM levels at Day 9, indicating that predominant IgG reactions were induced by the dual immunizations. A large inter-individual variability in KLH-specific IgM and IgG production was observed in all strains. However, levels of the KLH-specific antibodies were considered sufficient for the evaluation, even in Sprague-Dawley and Wistar rats reported as strains with a wide range of variability since immunosuppression of CPA on responses in both anti-KLH IgM and IgG were observed in all strains to the same extent. In addition, the sensitivity of the KLH-ELISA assay system detecting the immunosuppressive effects of CPA was comparable to other assay systems with PFC assay or ELISA using SRBC. The results here demonstrated that these experimental designs could provide valuable information about the influence on both the primary and secondary humoral immune responses in rats when exposed to potential immunomodulatory drugs. Furthermore, the design of the presented TDAR study would support comprehensive evaluation together with the outcome of the conventional general toxicity study. [ABSTRACT FROM AUTHOR]

In the previous paper 1, a novel type of semi-active damper that is composed of a cylinder injected with Magnetic Fluid (M.F.) and a magnetic flux controller was proposed for improving the ride comfort of trains. In this paper, at first, a modified model considering nonlinear characteristic of M.F. such as a Non-Newtonian-Fluid is proposed. Next, in order to enhance the control effects, two kinds of improvements are made in the semi-active damper. One is to change the voltage control input to an electromagnet into the current control input. The other is to expand the control range for the M.F. damper by means of feeding a bias current to the electromagnet. Finally, the effects of the improved semi-active damper are shown by various digital simulations and vibration experiments. [ABSTRACT FROM AUTHOR]

Constituents in a distillation residue of Awamori (millet spirits) and their antioxidant activity are investigated in this study. The supernatant of the distillation residue obtained by centrifugation was partitioned with n-hexane, chloroform, ethyl acetate, and n-butanol against water to afford the corresponding solubles. Among them, n-hexane and chloroform solubles showed higher antioxidant potency than l-ascorbic acid by the bleomycin-Fe method. In chloroform solubles, seven cyclic dipeptides were identified along with ethyl 2-pyrrolidione-5-carboxylate, tyrosol, and ethyl p-hydoroxyphenyllactate. Antioxidant activity of ethyl p-hydoroxyphenyllactate was 4.2 times that of l-ascorbic acid, whereas cyclic dipeptides showed activity 0.89-1.29 times as strong as that of l-ascorbic acid. On the other hand, scavenging effect of cyclic dipeptides against O(2)(-.) and OH(.) by using electron spin resonance was also investigated. In the results, cyclo(l-Ile-l-Pro) showed significantly strong inhibitory effect against OH(.) (95.4% at 2.5 x 10-3 M) and cyclo(l-Phe-l-Pro), cyclo(l-Pro-l-Val), and cyclo(l-Leu-l-Pro) inhibited OH(.) 64.9, 54.1, and 51.0%, respectively, whereas alpha-tocopherol showed 37.7% inhibition, though only a few cyclic dipeptides weakly inhibited O(2)(-.).