Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the ...Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the joint is influenced by infilled concrete, stiffener length and relative dimensions of column and beam. It is found that the hysteresis curves obtained in the experiment are full and the joints have a good energy dissipation capacity. The nonlinear finite element models are also used to analyze the hysteresis behavior of the joints under reversed cyclic loads using ANSYS 8.0. The influences of the stiffener length and the infilled concrete are analyzed. Analytical results show that the stiffener length and the infilled concrete are critical for the joints. Furthermore, the skeleton curves of the finite element models are in good agreement with those of experiments.展开更多
Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages ...Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages were treated with 3D conformal radiotherapy to minimize the dose to bladder,rectum and head of both femora using four fields (4F),five fields (5F),six fields (6F) and ARC techniques to minimize the risk of over dose to bladder,rectum and femoral heads.Patients received a total dose between 76 to 78 Gy given in 38 to 39 fractions over 7.5 to 8 weeks.Results:It was observed that V95,D95,D50 and D5 values for planning target volume (PTV) were comparatively higher when planned by 5 fields technique than when planned by fixed field technique (91%,91%,90% and 91.4% for skip-scan technique versus 85%,87%,86% and 88% by fixed field).The organs like rectum and urinary bladder get much higher dose when treated by fixed field techniques than rotation or 5 fields technique,when comparison was made for V95,V50 and DM values for rectum and urinary bladder obtained by 5 fields technique planning and 4/6 field planning,the value for 5 fields technique was found to be lower than 4/6 field technique (1%,70% and 51% versus 13%,91% and 55% for rectum and 4%,25% and 51% versus 16%,38% and 56% for urinary bladder respectively).Conclusion:Similarly for femoral heads,planning by full rotational technique had been observed to be beneficial as compared to when planning was done by fixed field technique (0%,0% and 29% versus 0%,1% and 28%).展开更多
基金Supprorted by the Science and Technology Foundation of Jiangsu Construction Committee(JS200214)the Science Research Foundation of Nanjing Institute of Technology(KXJ08122)~~
文摘Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the joint is influenced by infilled concrete, stiffener length and relative dimensions of column and beam. It is found that the hysteresis curves obtained in the experiment are full and the joints have a good energy dissipation capacity. The nonlinear finite element models are also used to analyze the hysteresis behavior of the joints under reversed cyclic loads using ANSYS 8.0. The influences of the stiffener length and the infilled concrete are analyzed. Analytical results show that the stiffener length and the infilled concrete are critical for the joints. Furthermore, the skeleton curves of the finite element models are in good agreement with those of experiments.
文摘Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages were treated with 3D conformal radiotherapy to minimize the dose to bladder,rectum and head of both femora using four fields (4F),five fields (5F),six fields (6F) and ARC techniques to minimize the risk of over dose to bladder,rectum and femoral heads.Patients received a total dose between 76 to 78 Gy given in 38 to 39 fractions over 7.5 to 8 weeks.Results:It was observed that V95,D95,D50 and D5 values for planning target volume (PTV) were comparatively higher when planned by 5 fields technique than when planned by fixed field technique (91%,91%,90% and 91.4% for skip-scan technique versus 85%,87%,86% and 88% by fixed field).The organs like rectum and urinary bladder get much higher dose when treated by fixed field techniques than rotation or 5 fields technique,when comparison was made for V95,V50 and DM values for rectum and urinary bladder obtained by 5 fields technique planning and 4/6 field planning,the value for 5 fields technique was found to be lower than 4/6 field technique (1%,70% and 51% versus 13%,91% and 55% for rectum and 4%,25% and 51% versus 16%,38% and 56% for urinary bladder respectively).Conclusion:Similarly for femoral heads,planning by full rotational technique had been observed to be beneficial as compared to when planning was done by fixed field technique (0%,0% and 29% versus 0%,1% and 28%).
