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Precise levelling surveys were conducted from 2006 to 2013 on three levelling routes in the Tatun volcano group (TVG) located approximately 15 km northeast of Taipei, to detect deformation in relation to the volcano-hydrothermal activities of the TVG. Uplift was detected around the most active fumarole, Tayoukeng fumarole, throughout the period 2007 to 2011; the uplift rate throughout the period from March 2009 to March 2011 was reduced in comparison to the rate between 2007 and 2009. Following this, a dormant state or a small amount of subsidence was detected in the period March 2011 to March 2013. And throughout the period from June 2006 to March 2013, subsidence was centred on an area 0.5 km east of the summit of Mt. Cising, the highest peak in the TVG. A model of two spherical sources was therefore estimated from the deformation recorded from August 2007 to March 2011, using a genetic algorithm. A deflation source was obtained about 0.5 km northeast of Mt. Cising at a depth of 2 km; and an inflation source was situated approximately 1 km south of the Tayoukeng fumarole at a depth of 0.7 km. Based on previous seismic and AMT studies, the estimated sources are interpreted as being hydrothermal reservoirs. Because almost all the benchmarks around Mt. Cising show subsidence at a constant speed, we conclude that the deeper hydrothermal reservoir at a depth of 2 km may have been releasing hydrothermal fluid at a constant rate throughout the period from 2006 to 2013. However, it was suggested that in 2011 the shallower hydrothermal reservoir at a depth of 0.7 km changed from an inflation state to a dormant state (or small deflation) based on temporal vertical changes around Tayoukeng fumarole. A possible model for the volcano-hydrothermal system is therefore proposed. It is considered that the hydrothermal fluid may be supplied intermittently from the magma chamber to the deeper hydrothermal reservoir at a depth of 2 km (although this type of fluid input event may not have occurred during our research period), and that the hydrothermal fluid upwelling between Mt. Cising and Tayoukeng fumarole flows transversally into a highly cracked and fluid-saturated area that continues to Tayoukeng fumarole. The existence of a shallower hydrothermal reservoir at a depth of 0.7 km in the highly cracked and fluid-saturated area is therefore plausible.

Precise levelling surveys were conducted across the central Longitudinal Valley Fault, eastern Taiwan, to understand the deformation of the transition zone between the stable fault creep area and the asperity area. In order to investigate the surface relationship between the fault creep area and the geological condition of the transition zone, we established levelling routes in the Yuli, Chike-san, and Reishuei areas. The Yuli area forms the geological boundary of the Lichi Melange Formation, which is composed of chaotic mudstones containing numerous exotic blocks of various sizes and lithologies. Along the Yuli route, located on the Lichi Melange, an uplift rate of 30 mm/yr was detected during the period 2010–2012, suggesting that aseismic fault creep might be continuing with long-term stability. Along the Chike-san route, a vertical deformation rate of 8 mm/yr was detected in the period 2010–2011. However, a large deformation with an uplift rate of 40 mm/yr was detected in the period 2011–2012. Along the Reisuei route, we detected a deformation of 8 mm/yr in the period 2011–2012. A two-dimensional single-fault model was developed to discuss the slip distributions in the periods 2010–2011 and 2011–2012. Relatively large slip rates were estimated at two parts of the fault plane—one at a depth of ~ 1.5 km and another at a depth of ~ 4 km—in both periods. Because both parts of the fault plane show approximately the same slip distribution, we believe that the detected deformation resulted from an episodic acceleration event of creeping slip. The northern limit of the stable creep area may be the Yuli area. The episodic creep event occurred in the transition zone between the stable fault creep area and the asperity area. The boundary between the stable creep area and the episodic creep area is consistent with the geological boundary of the Lichi Melange Formation.

Purpose Localization of the femoral vein traditionally relies on palpation of femoral arterial pulsation. For establishing venous access under fluoroscopy guidance, we evaluated the relationship between common femoral veins (CFVs) and bony structures. Methods Sixty patients with abdominal computed tomography scans between October 2009 and May 2010 were selected randomly for inclusion in the study. We used the RaySum reconstruction technique to display the bony landmark from the iliac crest to the upper femur and the course of bilateral CFVs. Results Between the superior and middle femoral head lines, the bilateral CFV tended to locate between the inner and outer cortex lines of teardrop (68.3% on right side and 65.0% on left side). The CFV is located more laterally among people who are older than 50 years with statistical significance. Conclusion Bony structures provide reliable information for venous access of CFVs under fluoroscopy guidance. The course of bilateral CFVs is more laterally located among elder patients with statistical significance.

The thermal debinding of injection moulded silicon nitride components under nitrogen, air, and N 2 + 5% H 2 atmospheres at various temperatures was investigated. The softening points and bonding structure of binders, pore size distribution, density and strength were studied. Results indicated that a slow binder removing rate and control debinding atmosphere are essential to the sintered properties.