EmbraceNet for Activity: A Deep Multimodal Fusion Architecture for Activity Recognition

Human activity recognition using multiple sensors is a challenging but promising task in recent decades. In this paper, we propose a deep multimodal fusion model for activity recognition based on the recently proposed feature fusion architecture named EmbraceNet. Our model processes each sensor data independently, combines the features with the EmbraceNet architecture, and post-processes the fused feature to predict the activity. In addition, we propose additional processes to boost the performance of our model. We submit the results obtained from our proposed model to the SHL recognition challenge with the team name "Yonsei-MCML."Comment: Accepted in HASCA at ACM UbiComp/ISWC 2019, won the 2nd place in the SHL Recognition Challenge 201

The influence of surface residual stress on fatigue crack growth.

Residual stress exists in most structures and although it has been recognised for a long time, its complex mechanism and characteristics are still being intensively studied. Residual stress can be stratified into damaging residual stress and beneficial residual stress. Surface tensile residual stresses are generally known to reduce the mechanical properties of materials while compressive residual stresses improve the fatigue performance of components. This Ph.D. thesis reports the analytical and experimental work conducted to investigate both the damaging and beneficial effects of residual stress on fatigue crack growth in structural components. The detrimental effect of tensile residual stresses is studied through large scale fatigue testing of T-butt welded plates fabricated from High Strength Steels (HSS). Despite the growing use of HSSs in the offshore industry, the fatigue performance and corrosion resistance of welded joints made from such steels are still not clear. Due to their complex metallurgy and relatively poor weldability, there is still a lack of understanding of the residual stresses that arise from the welding process. This study involved modification and development conducted on a variable amplitude (VA) load-time sequence generator for the investigation of long life fatigue performance of HSS. Emphasis was given to the generation of a stationary load-time history and numerous analyses were presented to demonstrate the importance of the long term statistical nature of the load-time sequence on fatigue testing. Fatigue test results obtained were extensively compared with previous HSS corrosion fatigue studies. The effect of tensile residual stress on fatigue crack growth was investigated using a SIF weight function-based fatigue crack growth model. Two newly developed preferential cold working techniques termed stitch cold rolling and stitch shot peening were explored to investigate the beneficial effect of surface compressive residual stress on fatigue crack growth in mild steel plates. One of the main objectives of this study was to control the fatigue crack shape by the manipulation of surface residual stress fields. The stitch cold rolling technique was implemented using a custom-built cold rolling jig. The feasibility of preferential cold working techniques was further investigated by the fatigue testing of stitch shot peened specimens. Both experimental programmes yielded unprecedented fatigue crack growth results. A residual stress monitoring programme was conducted to study the residual stress relaxation behaviour under cyclic loading. The experimental test results enabled the investigation of SIF solutions in non-uniform stress fields. A novel fatigue crack growth evolution model, which takes into account residual stress relaxation effects, was developed using the powerful SIF weight function methods

An investigation of physics instructors\u27 beliefs and students\u27 beliefs, goals and motivation for studying physics in Thai Rajabhat universities

Students\u27 interest in physics seems to be decreasing at all levels of education in most countries including Thailand. This problem is likely to be influenced by physics teaching and learning processes. Instructors\u27 beliefs influence teaching strategies whereas students\u27 beliefs, goals and motivation influence learning strategies. The investigation of factors influencing teaching and learning will provide useful information for improving the teaching and learning of physics. This research aims to explore physics instructors\u27 beliefs about teaching and learning physics, students\u27 beliefs, goals and motivation for studying physics in Thai Rajabhat universities. A questionnaire was administered to instructors who teach introductory physics courses in Rajabhats throughout Thailand at the beginning of second semester in 2002. Questionnaires were administered to first year students who enrolled in introductory physics courses at two Rajabhat universities in the south of Thailand at the beginning and the end of that semester. Four case studies were conducted with instructors and students at the two Rajabhats during the semester

Thailand’s Digital Economy Transformation: Rectifying the Middle-Income Trap by Leveraging Digital Capabilities in the Agriculture Industry

The Thai government has been attempting to move the country out of the middle-income trap through digital economy strategies. Among these strategies, digital innovation is the most central. Leveraging digital capabilities in the agriculture industry, a sector that a large number of low-income farmers work in, conveys digital innovations to farmers. Digital innovation is expected to increase farmer incomes and ultimately help the country step out of the middle-income trap. This dissertation aimed to 1) identify the major challenges of digital economy transformation, 2) develop a model that explains digital agriculture innovations, 3) apply the model to real use cases of digital transformation, and 4) identify a set of lessons learned from the entire research model that can guide policymakers to leverage digital capabilities to advance the agriculture industry. The dissertation identified how digital capabilities might improve farmer welfare by using multiple case studies. Three cases were studied individually and then synthesized into a data model. The participants covered five groups of stakeholders: developers, government officers, mid-tier employees, user farmers, and non-user farmers. The findings provide a data model explaining the practices of digital agriculture innovations. Moreover, the results guide policymakers to invest in and implement digital strategies to advance the agriculture industry and help lift the middle-class economy. Digital policies, strategies, and investment programs can be implemented in the agriculture sector and applied to other industries such as automobile, healthcare, and tourism

People Living With, Not Dying From Disease: Patient Empowerment Through Anti-Retroviral Therapy and Possibilities for Social Change

In South Africa today, it is estimated that there are 6.5 million people living with HIV/AIDS, at least half a million of whom require urgent treatment. On the continent of Africa as a whole the numbers are even more startling. Unfortunately, although the South African government has now committed itself to rolling out anti-retroviral therapy through the public healthcare system, progress has been slower than expected. Yet in numerous sites around South Africa, rollout centres have been established successfully, even in the most rural parts of the country. These programmes rely on existing community initiatives, community health workers and volunteers, and positive people themselves to educate, counsel, and monitor ARV patients. In this study I suggest that this model of care can be extremely empowering for the patient and reconceptualises healthcare as a path to social change. Drawing primarily from the examples of Madwaleni Hospital in the Eastern Cape, and the Edendale community in KwaZulu-Natal. I examine the dynamics of ARV programmes and the ways in which they create the empowered patient -- one who is knowledgeable, articulate, and motivated to effect change in his/her personal life and the social conditions under which he/she lives. Finally, I relate the idea of patient empowerment to a philosophy of primary healthcare and analyse the potential of primary healthcare to improve health in communities through permanent social transformation

Contributions of Familiarity and Chunking to Visual Working Memory Capacity

Visual working memory (VWM) is responsible for the temporary storage of visual information required for perception and cognition. The capacity of VWM is surprisingly limited to three or four items. Despite decades of research, the nature of the capacity limit is still unclear, in part due to uncertainty about the main factors contributing to this limit. We approached this issue by exploring two instances in which memory performance is enhanced. Firstly, while controlling stimulus complexity and similarity, familiarity produced significant increases in both encoding rate and capacity. However, familiarity gained from training observers to simply recognise the stimuli did not produce any benefits for change detection. Secondly, the inclusion of statistical regularities in the displays produced significantly improved recall. However, only subjects with explicit awareness of the statistical regularities showed improvement, whereas unaware subjects showed no change in their recall performance. We extended this result by observing whether contralateral delay activity (CDA), a neural marker of the number of item-based representations held in VWM, reduces with explicit chunking. Although recall performance was significantly better, the CDA did not appear to index equivalent number of chunks, suggesting that online representations do not change with the use of explicit chunking. Instead, the behavioural benefit appears to rely on retrieval of a long-term memory representation (LTM) when recall is tested. These results indicate a major influence of LTM in guiding VWM performance. Behavioural data collected at the end of the trial, such as change detection or probed recall, appear inadequate for fully examining the nature of VWM. An embedded-process framework, in which activated LTM representations can fluidly shift into the focus of attention, is useful in interpreting these results and understanding the cognitive processes involved in memory