Abstract: A control method for an LLC resonant converter includes: dividing an input voltage into four voltage segments: a low voltage, a medium-low voltage, a medium-high voltage, and a high voltage, and correspondingly adopting a full-bridge PFM control mode, a full-bridge PWM control mode, a half-bridge PFM control mode, and a half-bridge PWM control mode respectively. This control method is applicable to a wide input voltage range to achieve steady-state control over an LLC resonant converter, and can maintain a high efficiency of the LLC resonant converter within the whole input voltage range and can also be used in scenarios where a wide output voltage occurs.

Abstract: A high-durability and long-scale-distance fiber grating sensor and a manufacturing method therefor, which relate to the technical field of fiber grating sensors. A fiber grating is disposed on the middle segment of a commercial optical fiber. A bushing, a woven fiber jacket layer, and a packaging structure are disposed on the periphery of the commercial optical fiber. The commercial optical fiber and the bushing therebetween are fixed by using fixing points in the bushing. Anchoring segments are disposed between the fixing points in the bushing and the woven fiber jacket layer. Two ends of the commercial optical fiber are sequentially connected to optical fibers on the anchoring segments and connecting optical fibers. Tail ends of the connecting optical fibers are connected to a transmission cable by using connecting flanges.

Abstract: A high-durability and long-scale-distance fiber grating sensor and a manufacturing method therefor, which relate to the technical field of fiber grating sensors. A fiber grating is disposed on the middle segment of a commercial optical fiber. A bushing, a woven fiber jacket layer, and a packaging structure are disposed on the periphery of the commercial optical fiber. The commercial optical fiber and the bushing therebetween are fixed by using fixing points in the bushing. Anchoring segments are disposed between the fixing points in the, bushing and the woven fiber jacket layer. Two ends of the commercial optical fiber are sequentially connected to optical fibers on the anchoring segments and connecting optical fibers. Tail ends of the connecting optical fibers are connected to a transmission cable by using connecting flanges.

Abstract: A concrete structure member strengthened with prestressed FRP elements includes a concrete structure body and a prestressed FRP element arranged on the former. An epoxy resin overlay surrounding the prestressed FRP element is provided to wrap it up, and a polymer concrete supplemental layer is provided outside the epoxy resin overlay. The concrete structure member can uniformly and effectively transfer the stress from the prestressed FRP element.

Abstract: A high-durability and long-scale-distance fiber grating sensor and a manufacturing method therefor, which relate to the technical field of fiber grating sensors. A fiber grating is disposed on the middle segment of a commercial optical fiber. A bushing, a woven fiber jacket layer, and a packaging structure are disposed on the periphery of the commercial optical fiber. The commercial optical fiber and the bushing therebetween are fixed by using fixing points in the bushing. Anchoring segments are disposed between the fixing points in the, bushing and the woven fiber jacket layer. Two ends of the commercial optical fiber are sequentially connected to optical fibers on the anchoring segments and connecting optical fibers. Tail ends of the connecting optical fibers are connected to a transmission cable by using connecting flanges.

Abstract: A mold and a method for integrally manufacturing a functional cored slab and a solid slab with a polygonal grid honeycomb structure. The mold for manufacturing the cored slab comprises a female mold and multiple male molds which are provided in the female mold. The male molds include polygonal cylinders capable of melting, dissolving, or vaporizing. A clearance exists between at least one pair of adjacent polygonal cylinders. The mold for manufacturing the solid slab is provided with a male mold main-body of polygonal cylinders which share the same shape and amount as the polygonal grids. The male mold main-body, which is made of one of the functional materials including sound insulating materials, flame retardant materials, and thermal insulating materials, is located in the frame-like female mold having a bottom plate. Clearances are provided between the adjacent male mold bodies. A casting method is adopted when manufacturing the slabs.

Abstract: An anchoring method for external bonding and reinforcing technique with prestressed fiber cloth mainly involves the following steps: stretching fiber cloth (1) on the surface of a reinforced member (2) firstly, and then bonding the prestressed fiber cloth (1) and the reinforced member (2) as a whole with resin. In addition, certain measures of installing a steel plate (5) for anchoring and using an anchor device (7) are applied to the anchorage end of the prestressed fiber cloth (1) on the end of the reinforced member (2). The prestress on the anchorage end of the prestressed fiber cloth (1) is partly or all released after thermosetting of the resin so as to eliminate or reduce the stress concentration on the end.

Abstract: A concrete structure member strengthened with prestressed FRP elements includes a concrete structure body and a prestressed FRP element arranged on the former. An epoxy resin overlay surrounding the prestressed FRP element is provided to wrap it up, and a polymer concrete supplemental layer is provided outside the epoxy resin overlay. The concrete structure member can uniformly and effectively transfer the stress from the prestressed FRP element.

Abstract: An inkless printing method with heating process is disclosed. In the method, a conventional printing paper (15) is used, and a printing head (4,27) contacts the printing paper directly or indirectly. A heating element (13,22) is placed in the printing head(4,27), which provides heat energy to cause a color change in a surface layer of the paper, thereby producing a character or an image. When the printing head (4,27) contacts the printing paper directly, a temperature of the printing head (4,27) is set to 100-1000° C.; and a stagnation time of the printing head (4,27) is set to 0.1-100 ms; when the printing head (4,27) contacts the printing paper indirectly, a temperature of the printing head (4,27) is set to 200-1000° C. The method does not need to use toner, ink or paint, and only needs conventional printing paper (15) and said heating process to achieve printing effect. A printing head unit to be used in said printing method is also disclosed.

Abstract: An anchoring method for external bonding and reinforcing technique with prestressed fiber cloth mainly involves the following steps: stretching fiber cloth (1) on the surface of a reinforced member (2) firstly, and then bonding the prestressed fiber cloth (1) and the reinforced member (2) as a whole with resin. In addition, certain measures of installing a steel plate (5) for anchoring and using an anchor device (7) are applied to the anchorage end of the prestressed fiber cloth (1) on the end of the reinforced member (2). The prestress on the anchorage end of the prestressed fiber cloth (1) is partly or all released after thermosetting of the resin so as to eliminate or reduce the stress concentration on the end.

Abstract: A mold and a method for integrally manufacturing a functional cored slab and a solid slab with a polygonal grid honeycomb structure. The mold for manufacturing the cored slab comprises a female mold and multiple male molds which are provided in the female mold. The male molds include polygonal cylinders capable of melting, dissolving, or vaporizing. A clearance exists between at least one pair of adjacent polygonal cylinders. The mold for manufacturing the solid slab is provided with a male mold main-body of polygonal cylinders which share the same shape and amount as the polygonal grids. The male mold main-body, which is made of one of the functional materials including sound insulating materials, flame retardant materials, and thermal insulating materials, is located in the frame-like female mold having a bottom plate. Clearances are provided between the adjacent male mold bodies. A casting method is adopted when manufacturing the slabs.