Abstract: A cascade-connected boost circuit is disclosed. The cascade-connected boost circuit includes a first-stage boost circuit, a second-stage boost circuit, an output terminal and a regulation filtering capacitor. The first-stage boost circuit includes an input terminal, a PWM generator, a first inductor and a first switch. The second-stage boost circuit includes a second inductor and a second switch. The PWM generator controls the first switch and the second switch to turn on or turn off simultaneously. A power supply from the input terminal respectively charges the two inductors via two paths when the two switches are turned on. The two inductors release energy when the two switches are turned off. The two switches share the voltage of the output terminal. The cascade-connected boost circuit according to the present invention solves the issues that the withstand voltage limit of a single switch and the limit of a duty cycle.

Abstract: An acoustic diode includes a phononic crystal medium, a nonlinear acoustic medium, a aluminum tubes contain the phononic crystal medium and the nonlinear acoustic medium. The phononic crystal medium is fabricated by alternately laminating a water layers and a glass layers in a periodic manner.

Abstract: An exemplary flat type heat pipe includes a hollow, flattened casing and a first wick structure and a second wick structure received in the casing. The casing includes a top plate and a bottom plate opposite to the top plate. The first wick structure includes a plurality of spaced protruding portions and grooves between every two adjacent protruding portions. The second wick structure is made of sintered metal powder. The first and second wick structures are disposed at inner sides of the bottom and top plates of the casing, respectively. The first and second wick structures contact each other. The casing defines two vapor channels at opposite lateral sides of the combined first and second wick structures, respectively.

Abstract: An exemplary flat heat pipe includes a hollow, flattened casing and a first wick structure and a second wick structure received in the casing. The casing includes a top plate and a bottom plate opposite to the top plate. The first wick structure is folded by a steel sheet with a plurality of pores, and the second wick structure is made of sintered metal powder. The first and second wick structures are disposed at inner sides of the bottom and top plates of the casing, respectively. The first and second wick structures contact each other. The casing defines two vapor channels at opposite lateral sides of the combined first and second wick structures, respectively.

Abstract: A coupler is presented that has high-directivity and low coupling coefficient variation. The coupler includes a first trace with a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The first trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge. Further, the coupler includes a second trace, which includes a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The second trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge.

Abstract: A coupler is presented that has high-directivity and low coupling coefficient variation. The coupler includes a first trace associated with a first port and a second port. The first trace includes a first main arm, a first connecting trace connecting the first main arm to the second port, and a non-zero angle between the first main arm and the first connecting trace. Further, the coupler includes a second trace associated with a third port and a fourth port. The second trace includes a second main arm.

Abstract: A coupler is presented that has high-directivity and low coupling coefficient variation. The coupler includes a first trace associated with a first port and a second port. The first port is configured substantially as an input port and the second port is configured substantially as an output port. The coupler further includes a second trace associated with a third port and a fourth port. The third port is configured substantially as a coupled port and the fourth port is configured substantially as an isolated port. In addition, the coupler includes a first capacitor configured to introduce a discontinuity to induce a mismatch in the coupler.

Abstract: An exemplary flat heat pipe includes a hollow, flattened casing and a first wick structure and a second wick structure received in the casing. The casing includes a top plate and a bottom plate opposite to the top plate. The first wick structure is formed by weaving wires, and the second wick structure is made of sintered metal powder. The first and second wick structures are disposed at inner sides of the bottom and top plates of the casing, respectively. The first and second wick structures contact each other. The casing defines two vapor channels at opposite lateral sides of the combined first and second wick structures, respectively. A method for manufacturing the heat pipe is also provided.

Abstract: An exemplary flat heat pipe with an evaporator section and a condenser section includes a hollow casing, and a first wick structure and a second wick structure in the casing. The second structure contacts an inner surface of the casing at the evaporator section. The first structure at the evaporator section includes a first contact portion contacting an inner surface of the second structure, and a first isolated portion from the inner surface of the second structure. The first isolated portion and the inner surface of the second structure define a first channel therebetween. The first structure at the condenser section includes a second contact portion contacting the inner surface of the casing, and a second isolated portion from the inner surface of the casing. The second isolated portion and the inner surface of the casing define therebetween a second channel communicating with the first channel.

Abstract: An exemplary flat heat pipe with an evaporator section and a condenser section includes a casing, and a first wick structure and a second wick structure in the casing. The casing defines a first vapor channel within the evaporator section. The first wick structure contacts an inner surface of the casing at the condenser section. The first wick structure includes a contact portion in contact with the inner surface of the casing, and an isolated portion from the inner surface of the casing. The isolated portion and the inner surface of the casing cooperatively define therebetween a second vapor channel in communication with the first vapor channel. The second wick structure contacts the inner surface of the casing at the evaporator section. The second wick structure joins the first wick structure at a joint between the evaporator section and the condenser section.

Abstract: An exemplary flat heat pipe with an evaporator section and a condenser section at opposite ends thereof includes a hollow flat casing, a first wick structure and a solid and sintered second wick structure. The first wick structure includes a top plate and a bottom plate opposite to the top plate. The first wick structure is received in the casing, and extends from the evaporator section to the condenser section. The second wick structure is disposed in the casing at the evaporator section. The second wick structure contacts the top and bottom plates and joins the first wick structure. A method for manufacturing the heat pipe is also provided.

Abstract: Cooling devices (i.e., a heat exchanger) based on polymers which exhibits a temperature change upon application or removal of an electrical field or voltage are disclosed. Also disclosed are methods for cooling using such polymers.

Abstract: There is provided a set of methods for generating state space models of general VLSI interconnect and transmission lines, trees and nets by closed forms with exact accuracy and low computation complexity. The state space model is built by three types of models: the branch model, the connection model and the non-connection model, that are block matrices in closed forms, arranged with topology. The main features are the topology structure, simplicity and accuracy of the closed forms of the state space models {A,B,C,D} or {A,B,C}, computation complexity of O(N) in sense of scalar multiplication times, where N is the total system order, practice of the modeling, ELO model simplification, and their optimization. For evenly distributed interconnect and transmission lines, trees and nets, the closed forms of state space model have the computation complexity of O(1), i.e., only a fixed constant of scalar multiplication times.

Abstract: This invention provides a laser trimming method for tuning the frequency of a spiral resonator, and for improving the characteristics of a high temperature superconductor filter comprised of high temperature superconductor spiral resonators, by tuning the individual high temperature superconductor spiral resonators. This invention also provides a method for tuning the resonance frequency of a high temperature superconductor planar coil. This invention also provides a laser ablation process for creating high temperature superconductor circuit elements.