630 research outputs found

    Drive care: System for monitoring driver’s concentration and consciousness using consumer grade electonnencephalogram (EEG) headset 護駕: 利用消費級可裝載腦波監測儀實現實時監控駕駛者專注度系統

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    As people increasingly drive cars for both work and personal purposes, the dangers posed by drug driving, drink driving or sleep-deprived driving are growing threats to society. Highly dangerous driving behaviour and numerous traffic accidents occur because drivers are insufficiently conscious or inadequately focused while driving... 不論是為了工作還是個人需要,不少人都愛自行駕車,但藥後駕駛、醉酒駕駛、或駕駛前睡眠不足,往往容易對巿民的安全構成威脅。司機無法保持清醒或專注地駕駛而導致高危駕駛行為或交通意外,屢見不鮮... Award: Silver奬項: 銀

    ECONOMIC RECOVERY OF PYRIDINE AND 3-METHYLPYRIDINE

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    The goal of this design project was to find the most cost effective way of recovering pyridine and 3-methylpyridine from a given impurity stream with a specific finished goods quality. Due to the multiple azeotropes that the organic components in the feed had with water, we had to first explore different methods of removing water. We explored two different approaches in depth – pervaporation and azeotropic distillation. Both processes allowed us to break the azeotropes with water by removing at least 98 wt% of the water and recover at least 88 wt% of pyridine. To get a 15% return on investments (ROI) by the third year of production, we found that the pervaporation method allowed us to pay up to 0.71/lbforthenecessaryfeedstream,whiletheazeotropicdistillationmethodgaveusaflexibilityofupto0.71/lb for the necessary feed stream, while the azeotropic distillation method gave us a flexibility of up to 0.82/lb. Using a feed value of 0.71/lbforbothprocesses,thetotalcapitalinvestment(TCI)forthepervaporationprocessis0.71/lb for both processes, the total capital investment (TCI) for the pervaporation process is 10.7 million with a net present value (NPV) of 1.8million,whiletheTCIforazeotropicdistillationis1.8 million, while the TCI for azeotropic distillation is 7.0 million with a NPV of $6.4 million. Taking both the finished goods quality specifications and economic profitability into account for our design project, we would recommend the azeotropic distillation process in recovering the most purified product

    Effects of Infrared Radiation and Heat on Human Skin Aging in vivo

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    Sunlight damages human skin, resulting in a wrinkled appearance. Since natural sunlight is polychromatic, its ultimate effects on the human skin are the result of not only the action of each wavelength separately, but also interactions among the many wavelengths, including UV, visible light, and infrared (IR). In direct sunlight, the temperature of human skin rises to about 40°C following the conversion of absorbed IR into heat. So far, our knowledge of the effects of IR radiation or heat on skin aging is limited. Recent work demonstrates that IR and heat exposure each induces cutaneous angiogenesis and inflammatory cellular infiltration, disrupts the dermal extracellular matrix by inducing matrix metalloproteinases, and alters dermal structural proteins, thereby adding to premature skin aging. This review provides a summary of current research on the effects of IR radiation and heat on aging in human skin in vivo

    What do we know about Housing Supply? The case of Hong Kong

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    The house price in Hong Kong is well-known to be "unaffordable." This paper relates the macroeconomy and the housing market of Hong Kong and argues that the housing supply plays a vital role in explaining the phenomenon. This paper also shows that there are some practical challenges in understanding the housing supply of Hong Kong, including the potentially complicated ownership structure of real estate development. While the discussion centers on the situation of Hong Kong, its lesson may also apply to the housing markets in other small open economies

    What do we know about Housing Supply? The case of Hong Kong

    Get PDF
    The house price in Hong Kong is well-known to be "unaffordable." This paper relates the macroeconomy and the housing market of Hong Kong and argues that the housing supply plays a vital role in explaining the phenomenon. This paper also shows that there are some practical challenges in understanding the housing supply of Hong Kong, including the potentially complicated ownership structure of real estate development. While the discussion centers on the situation of Hong Kong, its lesson may also apply to the housing markets in other small open economies

    Does an Oligopolistic Primary Market Matter? The Case of an Asian Housing Market

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    This paper takes advantage of the oligopolistic structure of the Hong Kong primary housing market and examines whether the time-variations of the market concentration are caused by or cause the variations of the local economic factors. The analysis also takes into consideration of the changes of the U.S. variables and commodity prices, which arguably may represent changes in the construction cost. We find clear evidence of time-varying responses of housing market variables to macroeconomic variables. Policy implications and directions for future research are also discussed

    Risk of thyroid dysfunction associated with mRNA and inactivated COVID-19 vaccines: a population-based study of 2.3 million vaccine recipients

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    Background: In view of accumulating case reports of thyroid dysfunction following COVID-19 vaccination, we evaluated the risks of incident thyroid dysfunction following inactivated (CoronaVac) and mRNA (BNT162b2) COVID-19 vaccines using a population-based dataset. / Methods: We identified people who received COVID-19 vaccination between 23 February and 30 September 2021 from a population-based electronic health database in Hong Kong, linked to vaccination records. Thyroid dysfunction encompassed anti-thyroid drug (ATD)/levothyroxine (LT4) initiation, biochemical picture of hyperthyroidism/hypothyroidism, incident Graves’ disease (GD), and thyroiditis. A self-controlled case series design was used to estimate the incidence rate ratio (IRR) of thyroid dysfunction in a 56-day post-vaccination period compared to the baseline period (non-exposure period) using conditional Poisson regression. / Results: A total of 2,288,239 people received at least one dose of COVID-19 vaccination (57.8% BNT162b2 recipients and 42.2% CoronaVac recipients). 94.3% of BNT162b2 recipients and 92.2% of CoronaVac recipients received the second dose. Following the first dose of COVID-19 vaccination, there was no increase in the risks of ATD initiation (BNT162b2: IRR 0.864, 95% CI 0.670–1.114; CoronaVac: IRR 0.707, 95% CI 0.549–0.912), LT4 initiation (BNT162b2: IRR 0.911, 95% CI 0.716–1.159; CoronaVac: IRR 0.778, 95% CI 0.618–0.981), biochemical picture of hyperthyroidism (BNT162b2: IRR 0.872, 95% CI 0.744–1.023; CoronaVac: IRR 0.830, 95% CI 0.713–0.967) or hypothyroidism (BNT162b2: IRR 1.002, 95% CI 0.838–1.199; CoronaVac: IRR 0.963, 95% CI 0.807–1.149), GD, and thyroiditis. Similarly, following the second dose of COVID-19 vaccination, there was no increase in the risks of ATD initiation (BNT162b2: IRR 0.972, 95% CI 0.770–1.227; CoronaVac: IRR 0.879, 95%CI 0.693–1.116), LT4 initiation (BNT162b2: IRR 1.019, 95% CI 0.833–1.246; CoronaVac: IRR 0.768, 95% CI 0.613–0.962), hyperthyroidism (BNT162b2: IRR 1.039, 95% CI 0.899–1.201; CoronaVac: IRR 0.911, 95% CI 0.786–1.055), hypothyroidism (BNT162b2: IRR 0.935, 95% CI 0.794–1.102; CoronaVac: IRR 0.945, 95% CI 0.799–1.119), GD, and thyroiditis. Age- and sex-specific subgroup and sensitivity analyses showed consistent neutral associations between thyroid dysfunction and both types of COVID-19 vaccines. / Conclusions: Our population-based study showed no evidence of vaccine-related increase in incident hyperthyroidism or hypothyroidism with both BNT162b2 and CoronaVac
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