Novel InGaP/GaAsSb/GaAs DHBTs

A study of the InGaP/GaAsSb/GaAs double heterojunction bipolar transistor (DHBT) is presented. Novel device structure is designed. A fully strained pseudomorphic GaAsSb with 8.0% Sb composition is used as the base layer, while an InGaP layer as the emitter which both eliminates the misfit dislocations and increases the valence band discontinuity at the InGaP/GaAsSb interface. A current gain of 22.6 has been obtained from the InGaP/GaAsSb/GaAs DHBT. Typical turn-on voltage of the device is 0.973 V which is 0.116V lower than that of traditional InGaP/GaAs HBT. Moreover, the current transport mechanism of the InGaP/GaAsSb/GaAs DHBTs is investigated. These results show that GaAsSb is a promising base material for reducing the turn-on voltage of GaAs HBTs.published_or_final_versio

Framework for Promoting Women's Career Development across Career Stages in the Construction Industry

Despite efforts to promote gender diversity, the construction industry in Australia remains one of the most male-dominated industries. Women, compared to their male counterparts, progress more slowly and encounter major obstacles to career development in the construction industry. Existing research tends to focus on broad factors that impact women's career development in all career stages despite the fact that women's career priorities often change as they progress through different career stages. This study applied Super's career development model to investigate the influential factors on women's career development across four career stages: explore (precareer), establishment (early career), midcareer, and late career. By conducting a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this research identified influential factors related to women's career development in the construction industry, namely, attitude, capability, interest, past experiences, family responsibilities, parental influences, role models, support, culture, organizational practice, and policies and regulations. Based on the women's empowerment framework, the identified factors were coded and synthesized into three dimensions: individual, relational, and environmental. The research finds there is a significant focus on providing relational and environmental support to women in construction, and less attention is given to individual factors. The review revealed that personal interest and parental perceptions in construction influence women's career development in precareer and early career stages, while masculine culture significantly impacts women's career development in all career stages. This study also summarizes the theoretical contributions and practical implications drawn from existing research on different stages of women's career development and provides guidance for further research

Thermal stability of current gain in InGaP/GaAsSb/GaAs double-heterojunction bipolar transistors

The thermal stability of current gain in InGaP/GaAsSb/GaAs double-heterojunction bipolar transistors (DHBTs) is investigated. The experimental results show that the current gain in the InGaP/GaAsSb/GaAs DHBTs is nearly independent of the substrate temperature at collector current densities > 10 A/cm2, indicating that the InGaP/GaAsSb/GaAs DHBTs have excellent thermal stability. This finding suggests that the InGaP/GaAsSb/GaAs DHBTs have larger emitter-base junction valence-band discontinuity than traditional GaAs-based HBTs. © 2004 American Institute of Physics.published_or_final_versio

Low turn-on voltage InGaP/GaAsSb/GaAs double HBTs grown by MOCVD

A novel InGaP/GaAs0.92Sb0.08/GaAs double heterojunction bipolar transistor (DHBT) with low turn-on voltage has been fabricated. The turn-on voltage of the DHBT is typically 150 mV lower than that of the conventional InGaP/GaAs HBT, indicating that GaAsSb is a suitable base material for reducing the turn-on voltage of GaAs HBTs. A current gain of 50 has been obtained for the InGaP/GaAs0.92Sb0.08/GaAs DHBT. The results show that InGaP/GaAsSb/GaAs DHBTs have a great potential for reducing operating voltage and power dissipation.published_or_final_versio

Current transport mechanism in InGaP/GaAsSb/GaAs double-heterojunction bipolar transistors

We have developed InGaP/GaAsSb/GaAs double-heterojunction bipolar transistors (DHBTs) with low turn-on voltage and high current gain by using a narrow energy bandgap GaAsSb layer as the base and an InGaP layer as the emitter. The current transport mechanism is examined by measuring both of the terminal currents in forward and reverse mode. The results show that the dominant current transport mechanism in the InGaP/GaAsSb/GaAs DHBTs is the transport of carriers across the base layer. This finding suggests that the bandgap offset produced by incorporating Sb composition into GaAs mainly appears on the valence band and the conduction-band offset in InGaP/GaAsSb heterojunction is very small. © 2004 American Institute of Physics.published_or_final_versio

High efficiency, low offset voltage InGaP/GaAs power heterostructure-emitter bipolar transistors with advanced thermal management

High efficiency, low offset voltage InGaP/GaAs power heterostructure-emitter bipolar transistors (HEBTs) have been demonstrated. The large signal performance of the HEBTs is characterized. Output power of 0.25 W with power added efficiency (PAE) of 63.5% at 1.9 GHz has been achieved from a 26-finger HEBT with total emitter area of 873.6 μm2. Output power of 1.0 W with PAE of 63% has been obtained from the composition of four above-mentioned power cells at the optimum conditions of impedance matching. The thermal performance of HEBT is presented and the results show better thermal management than conventional HBT. The experimental results demonstrate good power performance and capability of HEBTs.published_or_final_versio

Impaired vowel discrimination in Mandarin-speaking congenital amusics

2015-2016 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

InGaP/GaAsSb/GaAs DHBTs with low turn-on voltage and high current gain

An InGaP/GaAsSb/GaAs double heterojunction bipolar transistor (DHBT) is presented. It features the use of a fully strained pseudomorphic GaAsSb (Sb composition: 10.4%) as the base layer and an InGaP layer as the emitter, which both eliminates the misfit dislocations and increases the valence band discontinuity at the InGaP/GaAsSb interface. A current gain of 200 has been obtained from the InGaP/GaAsSb/GaAs DHBT, which is the highest value obtained from GaAsSb base GaAs-based HBTs. The turn-on voltage of the device is typically 0.914 V for the 10.4% Sb composition, which is 0.176V tower than that of traditional InGaP/GaAs HBT. The results show that GaAsSb is a suitable base material for reducing the turn-on voltage of GaAs HBTs.published_or_final_versio

SSN: Shape Signature Networks for Multi-class Object Detection from Point Clouds

Multi-class 3D object detection aims to localize and classify objects of multiple categories from point clouds. Due to the nature of point clouds, i.e. unstructured, sparse and noisy, some features benefit-ting multi-class discrimination are underexploited, such as shape information. In this paper, we propose a novel 3D shape signature to explore the shape information from point clouds. By incorporating operations of symmetry, convex hull and chebyshev fitting, the proposed shape sig-nature is not only compact and effective but also robust to the noise, which serves as a soft constraint to improve the feature capability of multi-class discrimination. Based on the proposed shape signature, we develop the shape signature networks (SSN) for 3D object detection, which consist of pyramid feature encoding part, shape-aware grouping heads and explicit shape encoding objective. Experiments show that the proposed method performs remarkably better than existing methods on two large-scale datasets. Furthermore, our shape signature can act as a plug-and-play component and ablation study shows its effectiveness and good scalabilityComment: Code is available at https://github.com/xinge008/SS

The use of tibial Less Invasive Stabilization System (LISS) plate [AO-ASIF] for the treatment of paediatric supracondylar fracture of femur: a case report

Paediatric supracondylar fractures of the femur are not common. The treatment options depend on the age of child, the site of the fracture, the pattern of injury and the surgeon's preference. We report a case of an 11-year old boy who sustained a comminuted displaced supracondylar fracture of the femur and was treated with indirect reduction and internal fixation with the Less Invasive Stabilization System (LISS) tibial plate