Search

Hybrid electrical vehicles and electrical vehicles are being actively developed. A hybrid electric vehicle motor design requires high efficiency, high power/weight ratio, and reliability from low rotor speed to high rotor speed. The permanent-magnet synchronous motor is used in order to fulfill these requirements. The purpose of this paper is to develop a permanent-magnet synchronous motor control method for all rotor speeds. This method increases the torque and the efficiency at high speed when compared to the ordinary current error feedback method. A method composed of two compensators is proposed to achieve this objective. One of the compensators controls the torque using the voltage phases. The other one is the ordinary current error feedback. Several correcting methods for the voltage phase compensator have been proposed for the compensator for many control demands. The validity of the proposed method was confirmed using simulation and experimental evaluations. Index Terms--AC motors drive, permanent-magnet motors, road vehicles, torque control, voltage control.

Byline: Atsunori Yoshino (1,3,5), Masataka Honda (3), Masahiro Ikeda (3), Satoko Tsuchida (3), Hiroshi Hataya (3), Satoru Sakazume (3), Yuriko Tanaka (3), Seiichiro Shishido (4), Hideo Nakai (2) Keywords: Peritoneal dialysis; Tenckhoff catheter; Outer cuff shaving; Tunnel infection; Therapy; Replacement therapy Abstract: Catheter replacement and cuff-shaving are performed as a surgical treatment against tunnel infection (TI) in patients on chronic peritoneal dialysis. The efficacy of catheter replacement is well established, but that of cuff-shaving is not. For the purpose of evaluating the efficacy of cuff-shaving, we compared the time interval between each procedure and subsequent TI. In order to perform this comparison, we reviewed data from 32 cuff-shaving procedures and 29 catheter replacement procedures at Tokyo Metropolitan Kiyose Children's Hospital in the period from 1 March 1991 to 1 May 2001, retrospectively. There was no significant difference in the time interval between each procedure and subsequent TI ( P =0.284). The incidence of recurrence was no more than 12.5% for the cuff-shaving procedures. The incidence of peritonitis due to post-surgery TI with the cuff-shaving procedures was 9.3% and 6.8% with the replacement procedure ( P =0.725). There was no significant variation in time interval to post-cuff-shaving TI according to the reason for the cuff-shaving procedure. In conclusion, cuff-shaving may be worth considering for TI in adequately selected patients. Author Affiliation: (1) Department of Pediatrics, Dokkyo University School of Medicine, Koshigaya Hospital, Saitama, Japan (2) Department of Urology, Dokkyo University School of Medicine, Koshigaya Hospital, Saitama, Japan (3) Department of Nephrology, Tokyo Metropolitan Kiyose Children's Hospital, Tokyo, Japan (4) Department of Urology, Tokyo Metropolitan Kiyose Children's Hospital, Tokyo, Japan (5) Department of Pediatrics, Dokkyo University, School of Medicine, Koshigaya Hospital, 2--1-50 Minamikoshigaya, Saitama 343--8555, Koshigaya, Japan Article History: Registration Date: 23/07/2004 Received Date: 20/02/2004 Accepted Date: 06/07/2004 Online Date: 17/09/2004

Chondroitin sulfate C (sodium salt) and heparin (sodium salt), which are both mucopolysaccharides and natural components, have been employed as chiral selectors in electrokinetic chromatography (EKC) for the separation of enantiomers of drugs. These additives are charged, linear, sulfated polysaccharides having large mass. Ionic and hydrophobic interactions are probably the bases for the separation. Among tested drugs that are electrically neutral or basic, trimetoquinol, diltiazem, and their related compounds were successfully enantioseparated by EKC with mucopolysaccharides, especially with chondroitin sulfate C. The choices of pH and the concentration of mucopolysaccharides were found to be important for improvement of enantioselectivity. The acidic buffer solutions were effective for enantioseparation of the solutes in the chondroitin sulfate C system, although no migration of the basic drugs was observed in the heparin system. The results were compared with the enantiomeric separation by EKC with dextran surfate (sodium salt). The method using chondroitin surfate C was successfully applied to the optical purity testing of the drug substances.