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Pseudo static tests of four full-scale edge joint specimens are implemented to study the seismic performance of joint in panelised modular steel structure. The hysteretic behavior, bearing capacity, deformation and energy dissipation capacity of joints are evaluated based on the measured load-displacement data. Furthermore, the failure modes and the effect of different variables on seismic performance of joint are analyzed. The test results show that failure modes of the joint include column wall bulge, connector deformation and beam flange local buckling. The hysteresis curves of CT2, CT3 and CT4 exhibit plump shuttle shape, the maximum equivalent viscous damping coefficients are 0.21～0.25, the ultimate storey drift angle reaches 0.07～0.09 rad, indicating the joint has excellent seismic performance and rotation capacity. Thickness of column wall in panel zone and angle steels would affect the seismic performance of joint significantly, vertical-splicing bolt type has a remarkable effect on the hysteretic performance and initial flexural stiffness of joint. The results provide technical support for the engineering application of the joint in panelised modular steel structure. [ABSTRACT FROM AUTHOR]

Objects: Mountain peak extraction technology determines the accuracy of the hill position classification and the efficiency of automatic classification of micro-landform. Because of the limitations of elevation and contour lines, such as loss of local mountain peaks and incomplete removal of false mountain peaks, other landform factors could be used to express the distribution feature around the mountain peaks. Methods: Based on the uniform distribution feature of the aspect around the mountain peaks, this paper proposes an efficient mountain peak extraction model, in which the aspect is centered on the mountain peak and gradually increases clockwise. Moreover, according to the ridge line fitting method and the recursive thought of depth first search algorithm, the false mountain peaks in the extraction results are removed, while the real mountain peaks are retained. Considering the negative influences of the terrain fragmentation of the entity digital elevation model(DEM), this paper experiments and analyzes with simulated DEM and entity DEM respectively. Results:The results show that the method overcomes the uncertainty of subjective threshold based on closed contour lines. The mountain peak extraction accuracy of simulated DEM can achieve 100% due to its continuity and smoothness. Considering the terrain fragmentation of entity DEM will make it ill-posed, we improve it by adjusting the aspect distribution constraint condition and obtain average extraction accuracy of 96.1%. Conclusions: An efficient mountain peak extraction model is proposed based on the digital terrain analysis technology and the uniform distribution feature of the aspect around the mountain peaks, and the topographic feature points are extracted from the perspective of terrain geometry. Compared with the traditional mountain peak extraction methods, the proposed method is relatively accurate and simple, and can effectively reduce the false mountain. [ABSTRACT FROM AUTHOR]

Objective　To explore the association between gene single nucleotide polymorphisms of SLC2A9 and susceptibility to pyrazinamide induced hyperuricemia （ PIHU） in Yunnan Han population. Methods　The polymorphisms of SLC2A9 gene rs2280205, rs3733591, rs3775948 and rs10939650 were detected by Mass ARRAY method. Genotype and allele frequency distribution were compared between the test group （n = 294） and the control group （n = 220） and analyzing the association between the polymorphisms of SLC2A9 with susceptibility to PIHU in different genetic models. Results　There were significant differences in genotype frequency and allele frequency distribution of rs2280205 between the two groups （P < 0.05). Patients carrying allele A had an increased risk of PIHU； rs2280205 polymorphism was significantly correlated with PIHU in co-dominant, dominant and recessive models （all P < 0.05). rs3733591 genotype frequency and allele frequency distribution between the two groups, the difference was statistically significant （P < 0.05), the patients with allele T increased the risk of PIHU. rs3733591 polymorphism was significantly correlated with PIHU in co-dominant, dominant and recessive models （all P < 0.05). rs3775948 genotype frequency and allele frequency distribution between the two groups, the difference was statistically significant （ all P < 0.001), the patients with allele C of PIHU increased risk； rs3775948 polymorphism was significantly associated with PIHU in both co-dominant and dominant models （P < 0.05). rs10939650 genotype frequency and allele frequency distribution between the two groups, the difference was statistically significant （ all P < 0.001), the patients with allele C of PIHU increased risk； rs10939650 polymorphism was significantly associated with PIHU in both co-dominant and recessive models (P < 0.05). Conclusion　SLC2A9 gene polymorphisms rs2280205, rs3733591, rs3775948 and rs10939650 may be associated with the susceptibility to PIHU in Yunnan Han population, and allele A of rs2280205, allele T of rs3733591, allele C of rs3775948 and allele T of rs10939650 may be risk factors for PIHU. [ABSTRACT FROM AUTHOR]