title: Noise considerations when determining phase of large-signal microwave measurements

authors: Blockley, Peter Stuart

subjects: intermodulation distortion

abstract: Advances in microwave instrumentation now make it feasible to accurately measure not only the magnitude spectrum, but also the phase spectrum of wide-bandwidth signals. In a practical measurement, the spectrum is measured over a finite window of time. The phase spectrum is related to the position of this window, causing the spectrum to differ between measurements of an identical waveform. It is difficult to compare multiple measurements with different window positions or to incorporate them into a model. Several methods have been proposed for determining the phase spectrum such that multiple measurements can be effectively compared and utilized in models. The methods are reviewed in terms of the information required to determine the phase and compared in terms of their robustness in the presence of measurement noise.

text: Noise considerations when determining phase of large-signal microwave measurements Advances in microwave instrumentation now make it feasible to accurately measure not only the magnitude spectrum, but also the phase spectrum of wide-bandwidth signals. In a practical measurement, the spectrum is measured over a finite window of time. The phase spectrum is related to the position of this window, causing the spectrum to differ between measurements of an identical waveform. It is difficult to compare multiple measurements with different window positions or to incorporate them into a model. Several methods have been proposed for determining the phase spectrum such that multiple measurements can be effectively compared and utilized in models. The methods are reviewed in terms of the information required to determine the phase and compared in terms of their robustness in the presence of measurement noise.

year: 2006

title: Accelerating the XGBoost algorithm using GPU computing

authors: Mitchell, Rory

subjects: computer science

abstract: We present a CUDA-based implementation of a decision tree construction algorithm within the gradient boosting library XGBoost. The tree construction algorithm is executed entirely on the graphics processing unit (GPU) and shows high performance with a variety of datasets and settings, including sparse input matrices. Individual boosting iterations are parallelised, combining two approaches. An interleaved approach is used for shallow trees, switching to a more conventional radix sort-based approach for larger depths. We show speedups of between 3x and 6x using a Titan X compared to a 4 core i7 CPU, and 1.2x using a Titan X compared to 2x Xeon CPUs (24 cores). We show that it is possible to process the Higgs dataset (10 million instances, 28 features) entirely within GPU memory. The algorithm is made available as a plug-in within the XGBoost library and fully supports all XGBoost features including classification, regression and ranking tasks.

text: Accelerating the XGBoost algorithm using GPU computing We present a CUDA-based implementation of a decision tree construction algorithm within the gradient boosting library XGBoost. The tree construction algorithm is executed entirely on the graphics processing unit (GPU) and shows high performance with a variety of datasets and settings, including sparse input matrices. Individual boosting iterations are parallelised, combining two approaches. An interleaved approach is used for shallow trees, switching to a more conventional radix sort-based approach for larger depths. We show speedups of between 3x and 6x using a Titan X compared to a 4 core i7 CPU, and 1.2x using a Titan X compared to 2x Xeon CPUs (24 cores). We show that it is possible to process the Higgs dataset (10 million instances, 28 features) entirely within GPU memory. The algorithm is made available as a plug-in within the XGBoost library and fully supports all XGBoost features including classification, regression and ranking tasks.

year: 2017

title: Journeys of Māori women in engineering and engineering trades: Navigating challenges and embracing identity

authors: Moridnejad, Maryam

subjects: engineering

abstract: CONTEXT 
This paper reports a study that explores the lived experiences of five Māori women in New Zealand who are engaged in engineering and engineering trades, aiming to inspire more Māori women to join these fields. Through in-depth interviews, three key phases of their lives are examined: upbringing, educational experiences, and professional encounters. The research identifies barriers and strategies these women employed, revealing themes such as identity development, stereotyping, cultural identity, determination, and support.  

PURPOSE OR GOAL
Diversity remains a persistent concern within traditionally male-dominated fields such as engineering and trades. Literature underscores the invaluable contributions of a diverse workforce, including fresh perspectives, insights, and innovative problem-solving approaches. Efforts to enhance diversity in engineering education must address systemic barriers across all levels of education. The aim of this study is to give voice to Māori women in engineers and engineering trades. The study explores participants' career choices, childhood, schooling, tertiary education, and workplace experiences.

APPROACH OR METHODOLOGY/METHODS
The study is underpinned by a feminist poststructuralist conceptual framework, emphasizing that knowledge is constructed rather than discovered, and power relations are shaped within cultural and societal contexts. Data collection involved an initial short questionnaire and two semi-structured interviews. Qualitative inductive analysis was used. Early thematic coding occurred during the analysis of initial questionnaires to identify key themes for the interviews. Interview data were coded inductively by research assistants and cross-checked by the main researchers to find common themes. In a further analysis phase, interview transcripts were loaded into ChatGPT to identify key commonalities, which were compared with researchers’ codes to finalize the themes. These themes framed the discussion and provided a basis for understanding the lived experiences of Māori women in engineering and engineering trades.

ACTUAL OR ANTICIPATED OUTCOMES
The lives and experiences the five Māori women in this study illuminate the unique experiences and challenges faced by indigenous women pursuing careers in engineering and engineering trades. By amplifying their voices, this research highlights their perspectives, celebrates their agency and resilience, and showcases how they assert themselves, overcome challenges, and advocate for gender equality in their professions. Common themes such as identity development, others’ beliefs and attitudes, cultural identity, determination, and support and encouragement frame the discussion, assisting in demystifying societal realities and gaining insight into their social realities. This research aims to empower and make these women visible. The findings highlight the need for timely career guidance in schools, dismantling gender stereotypes early, and integrating Māori culture into workplaces to foster equity and inclusion.

CONCLUSIONS/RECOMMENDATIONS/SUMMARY
Collaborative efforts from educators, researchers, and policymakers are needed to address systemic barriers and create inclusive pathways for indigenous women and other underrepresented groups into engineering. Flexible support services tailored to the diverse needs are essential for facilitating success in these fields. The researchers suggest further research should focus on longitudinal studies tracking the career trajectories of minority groups, exploring how cultural and gender identities influence educational experiences, evaluating the effectiveness of existing support programmes, and examining the role of mentorship and support networks in empowering minority students to succeed in engineering and trades careers.

text: Journeys of Māori women in engineering and engineering trades: Navigating challenges and embracing identity CONTEXT 
This paper reports a study that explores the lived experiences of five Māori women in New Zealand who are engaged in engineering and engineering trades, aiming to inspire more Māori women to join these fields. Through in-depth interviews, three key phases of their lives are examined: upbringing, educational experiences, and professional encounters. The research identifies barriers and strategies these women employed, revealing themes such as identity development, stereotyping, cultural identity, determination, and support.  

PURPOSE OR GOAL
Diversity remains a persistent concern within traditionally male-dominated fields such as engineering and trades. Literature underscores the invaluable contributions of a diverse workforce, including fresh perspectives, insights, and innovative problem-solving approaches. Efforts to enhance diversity in engineering education must address systemic barriers across all levels of education. The aim of this study is to give voice to Māori women in engineers and engineering trades. The study explores participants' career choices, childhood, schooling, tertiary education, and workplace experiences.

APPROACH OR METHODOLOGY/METHODS
The study is underpinned by a feminist poststructuralist conceptual framework, emphasizing that knowledge is constructed rather than discovered, and power relations are shaped within cultural and societal contexts. Data collection involved an initial short questionnaire and two semi-structured interviews. Qualitative inductive analysis was used. Early thematic coding occurred during the analysis of initial questionnaires to identify key themes for the interviews. Interview data were coded inductively by research assistants and cross-checked by the main researchers to find common themes. In a further analysis phase, interview transcripts were loaded into ChatGPT to identify key commonalities, which were compared with researchers’ codes to finalize the themes. These themes framed the discussion and provided a basis for understanding the lived experiences of Māori women in engineering and engineering trades.

ACTUAL OR ANTICIPATED OUTCOMES
The lives and experiences the five Māori women in this study illuminate the unique experiences and challenges faced by indigenous women pursuing careers in engineering and engineering trades. By amplifying their voices, this research highlights their perspectives, celebrates their agency and resilience, and showcases how they assert themselves, overcome challenges, and advocate for gender equality in their professions. Common themes such as identity development, others’ beliefs and attitudes, cultural identity, determination, and support and encouragement frame the discussion, assisting in demystifying societal realities and gaining insight into their social realities. This research aims to empower and make these women visible. The findings highlight the need for timely career guidance in schools, dismantling gender stereotypes early, and integrating Māori culture into workplaces to foster equity and inclusion.

CONCLUSIONS/RECOMMENDATIONS/SUMMARY
Collaborative efforts from educators, researchers, and policymakers are needed to address systemic barriers and create inclusive pathways for indigenous women and other underrepresented groups into engineering. Flexible support services tailored to the diverse needs are essential for facilitating success in these fields. The researchers suggest further research should focus on longitudinal studies tracking the career trajectories of minority groups, exploring how cultural and gender identities influence educational experiences, evaluating the effectiveness of existing support programmes, and examining the role of mentorship and support networks in empowering minority students to succeed in engineering and trades careers.

year: 2024