<span>A dc-dc zeta converter is a switch mode dc-dc converter that can either step-up or step-down dc input voltage. In order to regulate the dc output voltage, a control subsystem needs to be deployed for the dc-dc zeta converter. This paper presents the dc-dc zeta converter control. Unlike conventional dc-dc zeta converter control which produces a controller based on the nominal value model, we propose a convex polytope model of the dc-dc zeta converter which takes into account parameter uncertainty. A linear matrix inequality (LMI) is formulated based on the linear quadratic regulator (LQR) problem to find the state-feedback controller for the convex polytope model. Simulation results are presented to compare the control performance between the conventional LQR and the proposed LMI based controller on the dc-dc zeta converter. Furthermore, the reduction technique of the convex polytope is proposed and its effect is investigated.</span>

No abstract

Dr. Masao Ikeda, stated that the journal promotes the policy of SICE to expand the international cooperation. The Editorial Board makes efforts for swift publications. One year to go to the tenth anniversary of the journal, it is my great pleasure to publish the fi rst issue of Volume 10. To prepare the celebration, the journal will publish several invited papers by world-renowned researchers covering various areas of SICE during this year. The invited papers will be important contributions to the research community from wider viewpoints of the subjects. For the past nine years, SICE JCMSI has been trying to make the activities of SICE visible. Along this policy, the journal published several special issues featuring major symposiums organized by divisions of SICE. These included the special issue on Frontiers in

Malignant Fibrous Histiocytoma with diver's bone infarct is rarely reported. 51 year old man, engaged in diving for about twenty three years. He was treated operativery, bone grafting in the head of right femur and left humerus, under a diagnosis of diver disease when he was age of thirty two. He was admitted with a pain in right thigh in January 1978.Tumor was palpated in right thigh with local heatness and swelling. Roentgenogram in right distal end femur and bone scintigram revealed a high concentration at the site of the lesion. Arteriogram showed a hypervascularity at the site of same lesion.Amputation and infusion of anticancers was performed. However it is interesting whether there is relation shiip between bone infrartcion and tumor or not.