Signal Integrity Analysis for High Speed Digital Circuit

This dissertation report marks the commencement of the Final Year Project (FYP) titled Signal Integrity Analysis for High Speed Digital Circuit. This project is a study on various signal integrity (SI) issues that could possibly come into play on Printed Circuit Boards (PCBs). This project is conducted to analyze and grasp a better understanding on the nature of the problem, how the problem is manifested in circuits and what design solutions can be employed to minimize its effects. Such a study is not something new but is definitely getting more crucial as the vast improvement in chip fabrication technology leads to logic families operating at a much higher speed, resulting to a faster rise time which will worsen the noise phenomena, i. e. reflection, crosstalk, and power system stability during component switching. Several causes to signal integrity issues on the printed circuit boards are analyzed and both proper and improper circuit design techniques are implemented on the Advanced Design System (ADS) software for data collection and analysis. Deliverables at the end this project would be the simulation results to support the study, whereby several simulations are conducted to demonstrate and verify the theoretical study of signal integrity issues. Besides that, the designs will then be fabricated on a two-layer microstrip board and tested on the Digital Communication Analyzer (DCA) to obtain more practical results. A project Gantt chart is attached in the appendix to illustrate the work flow and anticipated progress

Oestrogen and thyroid hormone interactions in the regulation of bone mass

Osteoporosis is characterised by low bone mass, reduced bone mineral density and a deterioration of bone microarchitecture, resulting in increased susceptibility to fragility fractures. Oestrogen deficiency and thyrotoxicosis are established risk factors for osteoporosis. Oestrogen and thyroid hormone have opposing actions on adult bone and I hypothesise that accelerated bone loss at the menopause is due to unopposed actions of thyroid hormone on the skeleton. To test this hypothesis, I investigated the effect of altered thyroid status on the skeleton in adult sham-operated and ovariectomised wild type and thyroid hormone receptor (TR) α and β knockout mice (TRα0/0 and TRβ-/-). Skeletal phenotype analysis included determination of structural, densitometric, histomorphometric and biomechanical parameters. Skeletal phenotypes of euthyroid wild type mice were compared to hypothyroid and thyrotoxic wild type as well as TRα0/0and TRβ-/- mice. Bone mass was elevated in TRα0/0and reduced in TRβ-/- mice despite similar bone formation rates. These data suggest that the differences in bone mass are due to differing osteoclast activity. The skeletal phenotypes of TRα0/0 and TRβ-/- mice following manipulation of thyroid status were then described in detail. TRβ-/- and wild type mice rendered hypothyroid, had significantly lower bone formation than hypothyroid TRα0/0 mice suggesting that, in the absence of thyroid hormone, TRα may inhibit bone formation. Finally, the effect of oestrogen withdrawal in each of these groups of mice was also investigated. These studies demonstrate oestrogen deficiency bone loss was greater in hypothyroid compared to hyperthyroid mice, indicating that accelerated bone loss following oestrogen withdrawal cannot result from unopposed actions of thyroid hormones. Nevertheless, the studies contained in this thesis provide new insight regarding the roles of TRα and TRβ in bone maintenance and the effects of interactions between oestrogen and thyroid hormones on the regulation of bone mass.Open Acces

STUDY ON THE INFLUENCE OF SAFETY EDUCATION ON THE WILLINGNESS OF CONSTRUCTION WORKERS TO HABITUAL SAFETY BEHAVIOUR

In order to explore the impact of safety education on the willingness of construction workersto habitual safety behaviours, the relevant literatures are analysed, relevant research hypothesesare proposed, and the theoretical model of habitual safety behaviour willingness influencing factorsis established, and the verification and analysis are carried out by means of inter-groupexperiments. The results show that different types of safety education have different influences onthe willingness of construction workers to habitual safety behaviours under the mediating role oftime scale adjustment and perceptual behaviour control

Northwestern Pacific typhoon intensity controlled by changes in ocean temperatures.

Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate [that is, Representative Concentration Pathway (RCP) 4.5] climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100

Vocabulary Learning Activities Employed by Chinese English-Major Undergraduates and Their Reflections on the Activities

Chinese English-major undergraduates face ademanding task regarding English vocabulary learning. Previousstudies have focused on vocabulary learning strategies. Fewstudies have examined what learners actually do to tacklevocabulary learning tasks. The current study adopted qualitativeresearch methods. Findings are reported in the following aspects:1) what vocabulary learning activities do Chinese English-majorundergraduates employ regarding English vocabulary learningtasks? 2) What measurements do they use to evaluate theirlearning results? And 3) what difficulties do these learnersencounter

Therapeutic potential of a combination of recombinant human growth hormone (r-hGH) and vitamin D in children with idiopathic short stature

Purpose: To study the effectiveness and clinical significance of recombinant human growth hormone (rhGH) in combination with vitamin D in the treatment of idiopathic short-stature children.Methods: A total of 90 idiopathic short-stature children admitted at Children Health Care Center of Shiyan Maternal and Child Health Care Hospital, Shiyan between March 2017 and March 2020 were assigned to three groups: A, B and C, based on dose of r-hGH given. Group A received r-hGH at a dose of 0.26 mg/kg/week, while groups B and C received r-hGH at doses of 0.35 and 0.42mg/kg/week, respectively. All the patients were given vitamin D along with the r-hGH doses administered. Height, growth rate, bone age, height standard deviation score, fasting blood glucose, thyroid function and treatment effectiveness were determined and compared among the three groups before treatment, and one year after treatment.Results: Significantly higher height standard deviation score, growth rate, bone age, and height were observed in the three groups of patients after one year of treatment than before treatment, with group A < group B < group C (p < 0.05). Fasting blood glucose and thyroid function were not significantly different amongst the three groups after treatment (p < 0.05). Group C showed the highest treatment effectiveness, followed by group B, and then group A (p < 0.05).Conclusion: The use of a combination of r-hGH and vitamin D produces a favorable treatment effectiveness in idiopathic short-stature children. However, further clinical trials are required to validate this treatment strategy

Thermal diffusion in fabrics and a graphics algorithm for apparel pattern reconstruction

This paper proposes a new apparel pattern-reconstruction method, which breaks sets of patterns into multiple parts according to special thermal characteristics in different parts of human body

Multivariate adaptive regression splines for estimating riverine constituent concentrations

Regression-based methods are commonly used for riverine constituent concentration/flux estimation, which is essential for guiding water quality protection practices and environmental decision making. This paper developed a multivariate adaptive regression splines model for estimating riverine constituent concentrations (MARS-EC). The process, interpretability and flexibility of the MARS-EC modelling approach, was demonstrated for total nitrogen in the Patuxent River, a major river input to Chesapeake Bay. Model accuracy and uncertainty of the MARS-EC approach was further analysed using nitrate plus nitrite datasets from eight tributary rivers to Chesapeake Bay. Results showed that the MARS-EC approach integrated the advantages of both parametric and nonparametric regression methods, and model accuracy was demonstrated to be superior to the traditionally used ESTIMATOR model. MARS-EC is flexible and allows consideration of auxiliary variables; the variables and interactions can be selected automatically. MARS-EC does not constrain concentration-predictor curves to be constant but rather is able to identify shifts in these curves from mathematical expressions and visual graphics. The MARS-EC approach provides an effective and complementary tool along with existing approaches for estimating riverine constituent concentrations