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As a special activity of the Student Cluster Competition at SC19 conference, we made an attempt to reproduce the scalability evaluations of a highly paralleled polynomial filtering eigensolver for computing planetary interior normal modes. Our experiments were conducted on a Mars dataset using a small scale 4-node cluster with Intel Skylake CPU architecture, while the original article’s were conducted on a Moon dataset using a large scale 256-node supercomputer with Intel CPU Skylake and KNL architectures. This article shares our experiences and observations from our reproducibility activity and discusses our findings on three main sections: the weak scalability, the strong scalability, and the relationships between variables. The results of weak scalability and strong scalability were successfully reproduced. But due to the differences on the problem scale, input dataset, and system architecture, different behaviors regarding the polynomial degree were observed.

The empirical attenuation functions for Local Magnitude (ML) currently used in Taiwan have been known for overestimated magnitudes around 0.2 compared with moment magnitude (MW) for shallow earthquakes (depths ≤ 35 km). Moreover, for deep earthquakes (depths > 35 km), ML (> 6) can be larger than MW around 0.5. Based on global observations and seismological theory, ML is equal to MW for magnitudes 4 - 6, whereas ML is smaller than MW for magnitudes > 6. This indicates that the attenuation functions for the Taiwan region need to be re-calculated. In this study, we used the new data set collected at the upgraded Central Weather Bureau Seismic Network (CWBSN24) from January 2012 to April 2019 and totally there are 692 events with ML ≥ 3 and 35228 amplitude data used for analysis. To accommodate the complicated tectonic environment in Taiwan, there are four attenuation functions, logA0(Δ), based on the focal depths and hypocentral distances, which are: http://tao.cgu.org.tw/images/docimage/2020061601T_Eq1.png for shallow earthquakes (focal depth, h ≤ 35 km), and http://tao.cgu.org.tw/images/docimage/2020061601T_Eq2.png for deep earthquakes (h > 35 km) where Δ is epicentral distances, R (= http://tao.cgu.org.tw/images/docimage/2020061601T_Eq3.png) is hypocentral distance. ML calculated by using the old attenuation functions for deep and large (ML > 5.5) earthquakes is larger than that by using the new ones about 0.4. With the new empirical attenuation functions, the relationship between ML and MW follows the global observations and also the new ML avoids the confusion for the public when releasing the official earthquake reports.

In the Hualien area, two Mw6.4 and Mw6.2 earthquakes, 20 km apart, occurred in February 2018 and April 2019 respectively. The former to the northeast, located offshore to ​​the Liwu river, triggered several earthquake clusters along the Milun fault and southward to the Longitudinal Valley, the suture of the Eurasian and the Philippine Sea plates; the latter to the southwest, located in the Central Range, also triggered several seismic swarms in the Central Range, along the Liwu river to the northeast and at Ji'an to the southeast. Except for the Milun fault, neither GPS nor InSAR observations detects significant surface deformation after the occurrence of these two main shocks, indicating that the earthquake ruptures mainly developed within the crust. Therefore, seismic observation becomes an efficient tool for revealing the seismotectonics of the two earthquake sequences. For monitoring the aftershock sequences, two days after the main shocks, we deployed two geophone arrays, 70 Z-component RefTek 125A TEXANs for two weeks in 2018 and 47 three-component Fairfield Nodal Z-Lands for one month in 2019, with 1-5 km station spacing around the Hualien City. These earthquake swarms were well recorded and analyzed through the dense seismic networks. The numbers of aftershock sequences manually identified are two-fold more than that issued by the Central Weather Bureau, Taiwan. The seismicity of the 2018 aftershock sequence, to depths of between 5-15 km, was significantly reduced within 10 days after the main shock. however, the seismicity of the 2019 aftershock sequence, to depths of between 2-50 km, was still above background seismicity rate 30 days after the main shock. The spatial distribution of the 2018 aftershock sequence could be related to a fault zone of the plate boundary, but that of the 2019 and the relocated 1986 aftershock sequences show a conjugate thrust fault pair beneath the eastern Central Range. Our results clearly depict several local tectonic structures that have not been observed at the northern tip of the Longitudinal Valley, not only a suture but also a transitional area from collision to subduction.

The Taiwan orogeny is forming along a complex plate boundary in which the Eurasian Plate (EUP) is subducting eastward beneath the Philippine Sea Plate (PSP). This complex plate boundary is situated in eastern Taiwan and results in large earthquakes occurred frequently in this region. For instance, in 1951, 1972, 1986, 2003, 2006, 2013, 2018, and 2019, earthquakes with magnitude greater than 6 occurred near or along the plate boundary and most of them caused serious damages. However, due to the complexity of the plate boundary from south to north of eastern Taiwan, the seismogenic structures for those events are very different. In order to understand the tectonic structures thoroughly in eastern Taiwan, we planned a integrated geophysical experiment, including seismic reflection, dense seismic array deployments, and magnetic survey from 2016 to 2020. There are 8 seismic reflection profiles along the Longitudinal valley from north to south. As a result, the seismic images show that the sedimentary deposits can reach ~1 km thickness in the northern part and is shallower toward to the southern part. The rocks below the sedimentary deposits are from the east flank of the Longitudinal valley, which belongs to the Eurasian plate. The dense array deployments from 2016-2019 around eastern Taiwan with 1-5 km spacing and totally more than 300 short-period stations deployed. During the deployments, we have captured two aftershock sequences in the north of eastern Taiwan in 2018 and 2019. The seismogenic zones with high-resolution tomography from dense seismic array data sets reveal that the plate interaction between the EUP and PSP. The physical behaviors of the seismogenic zones are related to the collision to subduction along the plate boundary from south to north. Also, the results of the magnetic survey in eastern Taiwan show that the high magnetic anomalies only sparsely distribute, which indicates the volcanic arc may not widely occupy than previous geological investigation. The results of this experiment provide a new thought of the tectonic processes along the plate boundary in eastern Taiwan.

The February 2018 M(w )6.4 earthquake in eastern Taiwan caused extensive damage in Hualien City. Although damaging earthquakes are common in this region, there are relatively few permanent seismic stations deployed. Two days after the main- shock, we deployed 70 temporary seismic stations around Hualien City for 12 days (8-19 February), and station spacing was 1-5 km. During this time, 2192 aftershocks were located from which 580 focal mechanisms were determined. The aftershock sequence extended about 25 km southwestward from the epicenter of the mainshock into the Longitudinal Valley and to depths between 5 and 15 km. Earthquake hypocenters indicate that the aftershocks took place along a near-vertical to steeply west-dipping plane in the north that becomes more diffuse in the south. Focal mechanisms are predominantly extensional, different than the left-lateral strike slip with thrust-component faulting of the mainshock. Very few events occurred in the uppermost crust at depths of less than 5 km, and their focal mechanisms are left-lateral strike-slip faulting. From the mainshock to the aftershocks, the stress changed rapidly from a north-northwest-oriented compressional axis (P axis) to the same direction for the extensional axis (T axis)., The authors thank Wen‐Yen Chang of National Dong Hua University, Yu‐Ting Kuo and Mr. Chin‐Shang Ku of the Insitute of Earth Sciences (IES), Academia Sinica, and Hsuan‐Yu Kuo of the National Central University for the assistance of the field deployment. H. K.‐C. is supported by MOST (MOST 104‐2628‐M‐008‐005‐MY3 and MOST 107‐2628‐M‐008 ‐004 ‐MY3).

Mw 6.4 Meinong earthquake occurred on 6 February 2016 in southern Taiwan, resulting in more than one hundred casualties and several collapsed buildings. The aftershocks occurred mostly at mid-to-lower crustal depths (10 - 30 km), related to a blind fault system. However, several centimeters of cosesimic surface uplift within the Liushuang, Erhchungli, and GutingKeng Formations, composed mainly of mudstone, was recorded from the InSAR results. The uplifted pattern is similar to that of GPS and leveling data from 2000 - 2010, which indicates the deformation is accomplished by creeping due to the shallow mudstone structure related to mud diapir. Previous studies have shown limited information about the shallow structure in this region due to few deployed seismic stations. We deployed 36 temporary seismic stations (~5 km spacing) in this study around one month after the main shock to obtain a 3-D shear wave shallow crustal velocity structure using ambient noise tomography. The reliable periods of group and phase velocities from Rayleigh waves were 0.6 - 5 s, corresponding to around 0 - 5 km at depths. As a result, the low S-wave pattern speeds at 0 - 4 km depths correspond to the uplift region from both InSAR data for the coseismic period and GPS and leveling data for the interseismic period. The results from this study are compatible with the reflected seismic profile. The results show that with dense seismic array deployment we can obtain high subsurface image resolution to link the relationship between the surface observations to the subsurface structures.

We perform a systematic detection of deep tectonic tremor beneath the southern Central Range in Taiwan using a dense, small‐aperture seismic array. Deployed in February 2011, the array has been recording tectonic tremor nearly continuously for 134 days, including tremor triggered by the 2011 M w 9.0 Tohoku‐Oki earthquake. We use broadband frequency–wavenumber beamforming and moving‐window grid‐search methods to compute array parameters for all continuous data and identify tremor as coherent nonimpulsive seismic signals with deep incidence angles. The obtained array parameters closely match with those of relocated local earthquakes and triggered tremor bursts located by the waveform envelope correlation and clustering (WECC) method, indicating the robustness of our array technique. During the 134‐day study period, we detect tremor for 44 days, with a total duration of 1481 min, three to six times as long as the detection of tremor by the WECC method. We find a relative quiescence in ambient tremor activity for about 20 days following the 2011 Tohoku‐Oki earthquake, suggesting that dynamic stresses from the distant mainshock triggered most tremor close to failure, resulting in a temporary lack of tremor activity. In some cases, we observe rapid tremor migration with a speed at the order of 40–50 km/hr that is similar to the speed of fast tremor migration along dip on narrow streaks in Japan and Cascadia. Our results suggest that dense array techniques are capable of capturing detailed spatiotemporal evolutions of tremor behaviors in southern Taiwan. Online Material: Tables of station coordinates and tremor event parameters, and figures of the moving‐window grid‐search test with local earthquakes, tremor triggered by the 2011 Tohoku‐Oki earthquake, and additional examples of detected ambient tremors.

Somewhere on the specific geological conditions of surrounding rock, adopt the different method, calculates the thickness of immediate roof in the area, the thickness of immediate roof was got, which to explore the suitable method for formation conditions of pressure control method, good effects have been achieved.

The slider-crank mechanism is a special case of the four bar linkage which is widely used in reciprocating machines. Flexible multi-body mechanisms that gain some motion through the deflection of flexible elements are classified as compliant mechanisms. Dynamics of flexible slider-crank mechanisms is presented in this paper. Both rigid and flexible parts are included in the slider-crank mechanisms. As one of the widely accepted dynamic analytical method for the multi-body system modeling, floating frame reference formulation has been applied to derive dynamic formulations. Simulations of dynamics of flexible slider-crank mechanisms have been carried out using Matlab. It was shown that flexibility of parts has a certain extent effects on mechanical properties of flexible system that disagree with that of rigid ones. Keywords: Floating frame reference formulation; Slider-crank; Deformation; Flexible multi-body

To investigate the relationship between serum level of bone morphogenetic proteins-2 (BMP-2) and heterotopic ossification (HO) in traumatic brain injury (TBI) and fractures patients, providing the theoretical evidence for the clinical prevention of HO.From December 2007 to January 2009, 145 with trama patients were selected. There were 96 closed primary traumatic brain injury patients, 1 penetrating primary traumatic brain injury, 29 fractures of the radius and ulna, 11 fractures of the humerus, 32 fractures of the tibia and fibula, 27 fractures of the femur. All patients were divided into three groups (i.e., group A, group B and group C) by the type of fracture. Fifty-seven patients in group A (TBI only), including 37 males and 20 females, ranged in the age from 29 to 61 years, with an average age of (43.91 +/- 11.09) years. The disease course was from 13 to 67 d, with an average duration of (18.96 +/- 10.46) d. Forty-eight patients in group B (fractures only), 25 males and 23 females, ranged in age from 31 to 54 years, with an average age of (41.73 +/- 8.41) years. The disease course was from 6 to 48 d, with an average duration of (16.02 +/- 8.71) d. Forty patients in group C (TBI combined with extremities fractures), including 23 males and 17 females, ranged in age from 30 to 60 years, with an average age of (45.87 +/- 14.15) years. The disease course was from 18 to 76 d, with an average of (21.28 +/- 13.02) d. Thirty-one extremities fractures with no significant separations or displacements of fragments were treated with traction reductions, cast immobilization or splint fixations. Sixty-eight fractures with significant separations and displacements of fragments were treated with intramedullary nail fixations or screw internal fixations. Sixty-three TBI patients were treated with open-skull surgeries immediately while 34 TBI patients were treated with stanching bleeding, reducing intracranial pressure and improving cerebral blood circulation. All patients were also divided into two groups (group D and group E) according to the 14-to 16-month follow-up X-ray film results. Seventeen patients in group D (HO had been found), including 11 males and 6 females, ranged in age from 29 to 55 years old, with an average age of (46.88 +/- 7.13) years. The disease course was from 6 to 30 d, with an average of (20.18 +/- 9.78) d. All 128 patients in group E (HO had been not found), including 74 males and 54 females, ranged in age from 33 to 61 years, with an average age of (43.31 +/- 12.94) years. The disease course was from 15 to 76 d, with an average of (18.42 +/- 11.58) d. The 49 subjects in group F (normal controls), 29 males and 20 females, ranged in age from 31 to 60 years, average (43.50 +/- 14.40) years. Peripheral blood samples were taken for the determination of BMP-2 in blood serum on 0.5, 3, 15 d and 30 d after fractures by enzyme-linked immunosorbent assay (ELISA). Analysis of variance and least significant difference test were done with the help of SPSS 13.0 statistic software.The incidence rates of HO between the TBI only patients (21.05%, 12/57) and the fractures only patients(4.17%, 2/48) were significant different (chi2=5.05, P0.05). Serum levels of BMP-2 at 0.5, 3 d and 15 d between group A and group B were significant different. Serum levels of BMP-2 at 0.5, 3, 15 d and 30 d between group D and group E were significant different. Serum levels of BMP-2 at each time in each group were higher than the control group (51.30 +/- 23.41 ng/L) (P0.01).High serum levels of BMP-2 in TBI only group is one of factors in causing HO. Serum level of BMP-2 at 15 d since fractures may be the obvervational index of HO prevention.

To explore the best surgical fusion level for adolescent idiopathic scoliosis (AIS) of PUMC II d(2) with finite element model (FEM).FEM (T(5)-S) of PUMC II d(2) idiopathic scoliosis was used to simulate upper thoracic curve, lower lumbar curve and double curve fusion manners. The pedicle of concave vertebral arch received 50, 100 and 150 N load respectively. Displacement of T(5) and T(11) on upper sagittal plane (displacement of Z axis positive value on upper sagittal plane, displacement of negative value on lower sagittal plane) and their different values were compared. T(5) displacement represented the outcomes of double curve orthopedics. T(11) displacement represented the outcomes of lower lumbar curve orthopedics. Their difference (T(5)-T(11)) represented the outcomes of upper thoracic curve orthopedics. Different fusion segments and displacement of T(5) and T(11) under different orthopedic forces were measured.In PUMC II d(2) lateral curvature, T(5) displacement on Z axis: fusion displacement of double curve was greater than the upper or lower curve alone (F = 8, P0.01). Difference of T(5)-T(11) displacement: double curve orthopedicsupper thoracic curve orthopedics alonelower lumbar curve orthopedics alone (F = 8, P0.01). Displacement of T(11) on Z axis: double curve orthopedicslower lumbar curve orthopedics aloneupper thoracic curve orthopedics alone (F = 8, P0.01).Fusing two curves achieves the best effect on the AIS of PUMC II d(2) in comparison with upper or lower curve fusion alone. Effects of 3 kinds of load on correction of upper thoracic curve: double curve orthopedicsupper thoracic curve orthopedics alonelower lumbar curve orthopedics alone. Effect of 3 kinds of load on correction of lower lumbar curve orthopedics alone: double curve orthopedicslower lumbar curve orthopedics aloneupper thoracic curve orthopedics alone. Three-dimensional finite element analysis is an effective method to analyze the biomechanics of scoliosis deformity correction and provides a virtually non-invasive verification manner. And it may optimize the surgical protocol.

To report the therapeutic effect of reverse fasciocutaneous flap pedicled with perforator branch of anterior medial malleolus artery for soft tissue defect on the dorsal side of foot.The perforator branch was located under the guidance of Doppler flowmeter. The flap was designed along the saphenous neurovascular axis. Then the flap was transferred reversely with the perforator branch as rotation point.From Feb. 2002 to Mar. 2008, 12 cases were treated and followed up for 6 - 18 months. All the flaps survived completely. The flap size ranged from 13.5 cm x 3.0 cm to 8 cm x 3 cm. The perforator branch located at 0.5 - 1.5 cm anterior-inferior to the medial malleolus. Both the cosmetic and functional results were satisfactory.The flap has a reliable blood supply and a flexible design. It is easily performed for soft tissue defect on the dorsal side of foot. It is a new type flap which combined neurocutaneous vascular flap with the perforator flap.