Continuous-wave (cw) blue laser generation at 426 nm by frequency doubling with a monolithic periodically poled KTP (PPKTP) cavity is reported in this paper. Without any free mirrors, the standing-wave cavity solely consists of a monolithic PPKTP crystal, and both ends of which are spherically polished and mirror-coated. An output power of 158 mW is obtained when the pump power is 350 mW. The conversion efficiency is 45%. The dependence of the conversion efficiency on the temperature and the incident fundamental power has been discussed. Such a system is integrally stable and compact for long-time operation under temperature control. The system is much more stable than the usual servo lock system for external cavity doubling.

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According to the philosophy of “partially weaken the core element of the BRB to protect the other part”, 12 specimens of the Triple Square Steel Tube Buckling-Restrained Brace (TSST-BRB) were designed with which the core element had notched. ABAQUS finite element method was used to investigate the performance of TSST-BRB with different notched kinds, number, length and depth of the core element. The analysis results indicated that the core element with annular notch was conducive to reduce the stress concentration of ends, and dissipate energy under tiny displacement. Two notches of the core element were better to reduce the peak stress of the notched segment and the stress concentration of ends. The length of notch should be controlled on 13.3%~20.0% of the length of core element. The energy dissipation capacity, yield displacement and yield capacity of the TSST-BRB were significantly influenced by the depth of notched core element. The depth of the notch should be controlled on 10%~23.3% of the thickness of core element.

Based on the limited demand of transfer beam sectional dimension of tall building structure with transfer story in Technical Specification for Concrete Structures of Tall Building, a high-level transfer frame-shear structure with viscous dampers is presented for simulating the mechanical behavior of the key components effect with consideration the transfer beam depth with 1/6, 1/8 and 1/10 calculation span. The analysis results indicate that the internal force of the transfer beam, frame-support column of transfer story, shear wall above transfer level and base shear wall is obviously reduced, with the reduction of the transfer beam depth. Comparison with the high-level transfer frame-shear structure, the internal force of the key components of the high-level transfer frame-shear structure with viscous dampers also is reduced. Therefore, the limited demand of the transfer beam sectional dimension and the construction measure of the shear wall could be properly reduced in the high-level transfer frame-shear structure with viscous dampers.