Studies on the Effect of Radio Frequency Field in a Cusp-Type Charge Separation Device for Direct Energy Conversion

In D-3He fusion power generation, an application of direct energy conversion is expected in which separation of charged particles is necessary. A cusp-type direct energy converter (CuspDEC) was proposed as a charge separation device, but its performance was degraded for a high density plasma. The goal of the present study is to establish an additional method to assist charge separation by using a nonlinear effect of a radio frequency (rf) electric field. Following to the previous study, we experimentally examine the effect of an rf field to electron motion in a CuspDEC device. Two ring electrodes were newly installed in a CuspDEC simulator and the current flowing into the electron collector located in the line cusp region was measured on an rf field application. The significant variation in the current was found, and an improvement of the charge separation can be expected by using the phenomenon appropriately

Deep-vein thrombosis detection rates and consideration of the living environment in a tsunami disaster area during the disaster reconstruction phase: A cross-sectional study

Introduction: Tsunami victims of the Great East Japan Earthquake were screened for deep-vein thrombosis(DVT) in order to compare the DVT incidence rates between temporary and non-temporary housing residentgroups. Material and methods: Lower extremity venous ultrasonography was performed on 290 subjects (64 menand 226 women; mean age = 71.9 ± 7.9 years) at 44 months after the disaster. All subjects completedquestionnaires to gather information about their background factors which included the Kessler PsychologicalDistress Scale: K6. Results: The DVT detection rate was 10.7% in the temporary group. In the non-temporary group, it was 11.3%among the subjects who previously lived in temporary housing. For the subjects who were living in their own homes it was 9.2%. Psychological distress levels measured by K6 were significantly higher in the temporary housinggroup than in the non-temporary housing group. The multivariate analysis showed that the background factorassociated with DVT risk was SV (soleal vein) dilatation in all subjects as well as in the non-temporary housinggroup, while hypertension and use of sleeping pills were found to be the factors in the temporary housing group. Conclusions: DVT detection rates were similar between the temporary and non-temporary housing groups,and were higher than that in the Japanese general population. The psychological distress level of the tsunamivictims measured by K6 was also higher in the temporary housing group than in the non-temporary housinggroup. It is necessary to establish a long-term and awareness-raising disaster victim support system

Recent Advancement of Research on Plasma Direct Energy Conversion

Present plasma direct energy conversion (DEC) system has been developed since proposal of ARTEMIS. The system for D-3He reactor is composed of cusp-type DEC (CuspDEC) for particle discrimination, traveling wave DEC (TWDEC) for recovery of high energy protons, and secondary electron DEC (SEDEC) for recovery of extremely accelerated protons. Studies on each device are in the third stage, where higher capability of each device will be derived. Various proposals and examinations were reported and the present paper treats the researches comprehensively and shows explanation and discussion for some researches: separation of high density plasma and ion-ion separation in CuspDEC, studies on modulation in TWDEC, and improvement of electron collection in SEDEC