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Objective: We aimed to examine long-term survival rate andthe risk factors of poor prognosis in patients whounderwent open surgery (OS) for abdominal aorticaneurysm (AAA).Materials and Methods: We performed a retrospective analysis of thepatients who underwent elective OS for AAAbetween 2005 and 2011 at Tokyo Medical andDental University Hospital. The relations betweenmortality rate and preoperative clinical factorswere examined.Results: For this study 195 patients were identified. Themortality was significantly related to size ofaneurysm, type of aneurysm, massive bleedingduring operation, age, anemia, uncontrolledhypertension, and comorbid chronic kidneydisease. No specific leading causes of death wereidentified for these increases in the mortalityrate. Cox proportional hazard model revealed thatanemia, hypertension, and chronic kidney disease(CKD) were independent predictive factors ofhigher mortality in the patients who underwent OSfor AAA.Discussion: In our previous study, high preoperative CRPlevel was correlated to long-term death rate afterendovascular aortic aneurysm repair (EVAR) forAAA. The difference might be attributed to the factthat OS relieves the aortic wall tension and reducesthe aortic inflammation, whereas EVAR does not,because of endoleak or endotension.

The demand for improving the steam turbine economic efficiency is being expected for both GTCC and conventional power plants. MHPS suggests HP/IP/LP separate casing and one bearing/rotor (one bearing between two casings) type steam turbine to enhance the turbine efficiency and reduce the cost of construction. Separate casing is preferable for blade aerodynamic performance, and one bearing/rotor is effective to reduce turbine bearing mechanical losses and turbine length. From the view point to design this type of rotor shaft arrangement, the most important point is to apply bearing technologies to permit the higher specific load and lower mechanical loss as well as for better dynamic oil film characteristics. The new two pads tilting journal bearing has been developed, utilizing MHPS’s experience on traditional two pads bearing with direct lubrication. The bearing structure and design parameters are optimized and good static and dynamic performance are obtained. Further, as practical countermeasures for a sub-synchronous vibration, the oil supply nozzle efficiency is improved, while properly adjusting supply oil flow distribution. The 610 mm size bearing test was conducted in-house test facility. The limit of specific load was verified, the bearing loss has become less than target.

平成26年度宇宙輸送シンポジウム（2015年1月15日-16日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県, Space Transportation Symposium FY2014 (January 15-16, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000036019, レポート番号: STCP-2014-019

平成26年度宇宙輸送シンポジウム（2015年1月15日-16日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県, Space Transportation Symposium FY2014 (January 15-16, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000036020, レポート番号: STCP-2014-020

Steam turbine is now facing strict market demands for further improvements in efficiency. To meet such demands, thrust bearing with high specific load makes a huge contribution to improvements in efficiency. Because the smaller thrust dummy diameter of rotor can be adopted and leakage flow through the thrust dummy can be reduced, in case thrust bearing allows higher specific load and allowable thrust force becomes bigger. MHI developed the thrust bearing with high specific load, which PEEK (polyether-ether-ketone) resin pad is applied. Both the laboratory bearing tests and long-time operation (from 2007) in MHI’s internal combined cycle power plant have been successfully accomplished. This PEEK resin thrust bearing is going to be applied to the actual plant. This article describes the performance and characteristics of PEEK resin thrust bearing and summary of laboratory test and long-time operation.Copyright © 2014 by ASME

平成25年度宇宙輸送シンポジウム（2014年1月16日-17日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県, Space Transportation Symposium FY2013 (January 16-17, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000016038, レポート番号: STCP-2013-038