Oscar Lau - Academia.edu (original) (raw)
Papers by Oscar Lau
Cornell University - arXiv, Jan 3, 2017
For nanotechnology, the semiconductor device is scaled down dramatically with additional strain e... more For nanotechnology, the semiconductor device is scaled down dramatically with additional strain engineering for device enhancement, the overall device characteristic is no longer dominated by the device size but also circuit layout. The higher order layout effects, such as well proximity effect (WPE), oxide spacing effect (OSE) and poly spacing effect (PSE), play an important role for the device performance, it is critical to understand Design for Manufacturability (DFM) impacts with various layout topology toward the overall circuit performance. Currently, the layout effects (WPE, OSE and PSE) are validated through digital standard cell and analog differential pair test structure. However, two analog layout structures: the guard ring and dummy fill impact are not well studied yet, then, this paper describes the current mirror test circuit to examine the guard ring and dummy fills DFM impacts using TSMC 28nm HPM process.
Three essays in applied economic theory
A disturbing feature of the conventional objective function for intertemporal decisions under unc... more A disturbing feature of the conventional objective function for intertemporal decisions under uncertainty is that the agent’s attitudes toward intertemporal substitution and risk aversion are entangled. This paper shows that, in contrast to common perception, the two attitudes can be completely disentangled under the expected utility theorem (EUT) by modeling each of them successively in two steps. The conventional form is nested as a special case where the functions describing the two attitudes are identical. The proposed framework requires only the standard axioms of the EUT, in addition to a regulatory assumption. It is flexible in accommodating different combinations of the two attitudes, indifferent to the timing of resolution of uncertainty, intuitive to interpret, and extendable to multiple goods. The objective function under the proposed framework is time inconsistent according to Strotz’s (1955) definition. I argue that Strotz’s notion of time consistency is misguided. It i...
Value in Health, 2021
Objectives: Emergence of severe acute respiratory syndrome coronavirus 2 infections and the resul... more Objectives: Emergence of severe acute respiratory syndrome coronavirus 2 infections and the resultant disease, COVID-19 led the world into 238 million cases and 4.8 million deaths over the first 22 months of the pandemic. While numerous vaccines have been developed to combat this pandemic, limited literature is available regarding the comparison of these vaccines. This study aims to systematically review and evaluate the immunogenicity and safety of COVID-19 vaccines compared with control arms in the healthy adult population. Methods: A literature search was conducted in PubMed, MEDLINE, Embase, and Cochrane up to July 4, 2021. Randomized controlled trials assessing the immunogenicity of any dose of COVID-19 vaccine in adults by anti-severe acute respiratory syndrome coronavirus 2 immunoglobulin G antibodies geometric mean titers (GMTs) and neutralizing antibodies GMT response at 28 days postimmunization compared with the control groups in the healthy adults were considered for inclusion. Groups at day 28 with the highest GMT were further examined for their adverse events. Results: Of the 341 citations retrieved, 19 were included. This covered a total of 16 vaccines involving 8342 subjects aged between 30.8 and 69.7 years, comprising 52.13% females. All studies reported GMT at or close to 28 days postvaccination compared with placebo and comparator, and 13 of 19 studies reported seroconversion rates. While 15 of 16 vaccines reported adverse events that ranged from mild to severe, 1 of 16 (AD26.COV2.S) noted 1 case of a vaccine-related serious adverse event-high fever 6 hours after vaccination. Local reactions (such as redness, pain, and swelling) and systematic reactions (such as fatigue, fever, and headache) were commonly noted. Safety between vaccines was similar; however, higher rates of severe adverse events were noted in Ad5-vectored COVID-19, AD26.COV2.S, ChAdOx nCoV-19, and mRNA-1273. No allcause mortality was documented in any vaccines. Conclusions: All 16 vaccines elicited an immune response substantially higher than the control groups while maintaining tolerable safety profiles.
Volume 5B: 41st Mechanisms and Robotics Conference, Aug 6, 2017
Soft actuators have drawn significant attentions from researchers with an inherently compliant de... more Soft actuators have drawn significant attentions from researchers with an inherently compliant design to address the safety issues in physical human-robot interactions. However, they are also vulnerable and pose new challenges in the design, fabrication, and analysis due to their inherent material softness. In this paper, a novel hybrid actuator design is presented with bio-inspirations from the lobster, or crustaceans in a broader perspective. We enclose a soft chamber with rectangular crosssection using a series of articulated rigid shells to produce bending under pneumatic input. By mimicking the shell pattern of lobsters' abdomen, foldable rigid shells are designed to provide the soft actuator with full protection throughout the motion range. The articulation of the rigid shells predefines the actuator's bending motions. As a result, the proposed design enables one to analyze this hybrid actuator with simplified quasi-static models and rigid-body kinematics, which are further validated by mechanical tests. This paper demonstrates that the proposed hybrid actuator design is capable of bridging the major design drawbacks of the entirely rigid and soft robots while preserving their engineering merits in performance.
SSRN Electronic Journal, 2016
A disturbing feature of the conventional objective function for intertemporal decisions under unc... more A disturbing feature of the conventional objective function for intertemporal decisions under uncertainty is that the agent's attitudes toward intertemporal substitution and risk aversion are entangled. This paper shows that, in contrast to common perception, the two attitudes can be completely disentangled under the expected utility theorem (EUT) by modeling each of them successively in two steps. The conventional form is nested as a special case where the functions
Tourism Economics, 2017
Business tourism has brought significant benefits to New Zealand’s tourism industry and economy. ... more Business tourism has brought significant benefits to New Zealand’s tourism industry and economy. This study aims to provide a better understanding of the impact of economic uncertainty on New Zealand’s business tourism. The panel data gravity model and the maximally correlated portfolio are used to investigate the impacts of economic policy uncertainty (EPU) indices of New Zealand and its key trading partners, along with tourism and aviation-related factors, on New Zealand’s business tourist flows from 2008 to 2015. The findings suggest that two economic factors (New Zealand’s EPU index and bilateral trade volumes) and two noneconomic factors (flying distance and total direct flight seats) are statistically significant in explaining some of the variations in business tourism flows. The results have important policy implications for New Zealand’s policymakers in understanding business visitor demands and planning their tourism strategies.
Journal of Economic Behavior & Organization, 2017
This paper considers "soft debt" as a social convention that facilitates long-term reciprocal rel... more This paper considers "soft debt" as a social convention that facilitates long-term reciprocal relationships. A player is said to follow a soft debt strategy if his decisions depend on the entire history with his counterpart only through their accrued soft debt balance. Under discrete benefits, there exist equilibria in which the players keep reciprocating as long as the debt balance does not exceed a certain limit.
Design of a single layer programmable Structured ASIC library
13th IEEE Symposium on Design and Diagnostics of Electronic Circuits and Systems, 2010
... Issue Date: 2010. Citation: CHAU CP Thomas, LEONG PH W, HO Man HO, CHAN Pui Wai, YUEN Chi Lap... more ... Issue Date: 2010. Citation: CHAU CP Thomas, LEONG PH W, HO Man HO, CHAN Pui Wai, YUEN Chi Lap, PUN Kong Pang, CHOY Chiu Sing Oliver, WU Yu Liang. 13th IEEE International Symposium on Design and Diagnosis of Electronic Circuits and Systems, 2010, p.. ...
2010 15th Asia and South Pacific Design Automation Conference (ASP-DAC), 2010
2017 IEEE International Conference on Robotics and Automation (ICRA), 2017
This paper presents preliminary results of the design, development, and evaluation of a hand reha... more This paper presents preliminary results of the design, development, and evaluation of a hand rehabilitation glove fabricated using lobster-inspired hybrid design with rigid and soft components for actuation. Inspired by the bending abdomen of lobsters, hybrid actuators are built with serially jointed rigid shells actuated by pressurized soft chambers inside to generate bending motions. Such bio-inspiration absorbs features from the classical rigid-bodied robotics with preciselydefined motion generation, as well as the emerging soft robotics with lightweight , physically safe, and adaptive actuation. The fabrication procedure is described, followed by experiments to mechanically characterize these actuators. Finally, an openpalm glove design integrated with these hybrid actuators are presented for a qualitative case study. A hand rehabilitation system is developed by learning patterns of the sEMG signals from the users forearm to train the assistive glove for hand rehabilitation exercises.
Lobster-inspired hybrid actuator
2017 IEEE International Conference on Robotics and Automation (ICRA), 2017
Classical rigid-bodied robotic systems are presented with proven success in theoretical developme... more Classical rigid-bodied robotic systems are presented with proven success in theoretical development and industrial applications, are recently challenged by the emergence of soft robotics due to a growing need in physical human-robot interactions (pHRI), such as wearable devices, medical robots, personal robots, etc. In this paper, we present the design and fabrication of a robust, hybrid bending actuator build from both rigid and soft components inspired by crustaceans, where its bending radius and axis can be mechanically programmed through the selective activation of the rigid exterior joints, actuated by the soft actuators inside. The hybrid actuator was experimentally measured in terms of bending and force tests to demonstrate the utility of this design. Finally, a case study was presented to demonstrate its capacity to adapt to specific objects geometry, anticipating its potential application in situations where compliance is the priority.
Cornell University - arXiv, Jan 3, 2017
For nanotechnology, the semiconductor device is scaled down dramatically with additional strain e... more For nanotechnology, the semiconductor device is scaled down dramatically with additional strain engineering for device enhancement, the overall device characteristic is no longer dominated by the device size but also circuit layout. The higher order layout effects, such as well proximity effect (WPE), oxide spacing effect (OSE) and poly spacing effect (PSE), play an important role for the device performance, it is critical to understand Design for Manufacturability (DFM) impacts with various layout topology toward the overall circuit performance. Currently, the layout effects (WPE, OSE and PSE) are validated through digital standard cell and analog differential pair test structure. However, two analog layout structures: the guard ring and dummy fill impact are not well studied yet, then, this paper describes the current mirror test circuit to examine the guard ring and dummy fills DFM impacts using TSMC 28nm HPM process.
Three essays in applied economic theory
A disturbing feature of the conventional objective function for intertemporal decisions under unc... more A disturbing feature of the conventional objective function for intertemporal decisions under uncertainty is that the agent’s attitudes toward intertemporal substitution and risk aversion are entangled. This paper shows that, in contrast to common perception, the two attitudes can be completely disentangled under the expected utility theorem (EUT) by modeling each of them successively in two steps. The conventional form is nested as a special case where the functions describing the two attitudes are identical. The proposed framework requires only the standard axioms of the EUT, in addition to a regulatory assumption. It is flexible in accommodating different combinations of the two attitudes, indifferent to the timing of resolution of uncertainty, intuitive to interpret, and extendable to multiple goods. The objective function under the proposed framework is time inconsistent according to Strotz’s (1955) definition. I argue that Strotz’s notion of time consistency is misguided. It i...
Value in Health, 2021
Objectives: Emergence of severe acute respiratory syndrome coronavirus 2 infections and the resul... more Objectives: Emergence of severe acute respiratory syndrome coronavirus 2 infections and the resultant disease, COVID-19 led the world into 238 million cases and 4.8 million deaths over the first 22 months of the pandemic. While numerous vaccines have been developed to combat this pandemic, limited literature is available regarding the comparison of these vaccines. This study aims to systematically review and evaluate the immunogenicity and safety of COVID-19 vaccines compared with control arms in the healthy adult population. Methods: A literature search was conducted in PubMed, MEDLINE, Embase, and Cochrane up to July 4, 2021. Randomized controlled trials assessing the immunogenicity of any dose of COVID-19 vaccine in adults by anti-severe acute respiratory syndrome coronavirus 2 immunoglobulin G antibodies geometric mean titers (GMTs) and neutralizing antibodies GMT response at 28 days postimmunization compared with the control groups in the healthy adults were considered for inclusion. Groups at day 28 with the highest GMT were further examined for their adverse events. Results: Of the 341 citations retrieved, 19 were included. This covered a total of 16 vaccines involving 8342 subjects aged between 30.8 and 69.7 years, comprising 52.13% females. All studies reported GMT at or close to 28 days postvaccination compared with placebo and comparator, and 13 of 19 studies reported seroconversion rates. While 15 of 16 vaccines reported adverse events that ranged from mild to severe, 1 of 16 (AD26.COV2.S) noted 1 case of a vaccine-related serious adverse event-high fever 6 hours after vaccination. Local reactions (such as redness, pain, and swelling) and systematic reactions (such as fatigue, fever, and headache) were commonly noted. Safety between vaccines was similar; however, higher rates of severe adverse events were noted in Ad5-vectored COVID-19, AD26.COV2.S, ChAdOx nCoV-19, and mRNA-1273. No allcause mortality was documented in any vaccines. Conclusions: All 16 vaccines elicited an immune response substantially higher than the control groups while maintaining tolerable safety profiles.
Volume 5B: 41st Mechanisms and Robotics Conference, Aug 6, 2017
Soft actuators have drawn significant attentions from researchers with an inherently compliant de... more Soft actuators have drawn significant attentions from researchers with an inherently compliant design to address the safety issues in physical human-robot interactions. However, they are also vulnerable and pose new challenges in the design, fabrication, and analysis due to their inherent material softness. In this paper, a novel hybrid actuator design is presented with bio-inspirations from the lobster, or crustaceans in a broader perspective. We enclose a soft chamber with rectangular crosssection using a series of articulated rigid shells to produce bending under pneumatic input. By mimicking the shell pattern of lobsters' abdomen, foldable rigid shells are designed to provide the soft actuator with full protection throughout the motion range. The articulation of the rigid shells predefines the actuator's bending motions. As a result, the proposed design enables one to analyze this hybrid actuator with simplified quasi-static models and rigid-body kinematics, which are further validated by mechanical tests. This paper demonstrates that the proposed hybrid actuator design is capable of bridging the major design drawbacks of the entirely rigid and soft robots while preserving their engineering merits in performance.
SSRN Electronic Journal, 2016
A disturbing feature of the conventional objective function for intertemporal decisions under unc... more A disturbing feature of the conventional objective function for intertemporal decisions under uncertainty is that the agent's attitudes toward intertemporal substitution and risk aversion are entangled. This paper shows that, in contrast to common perception, the two attitudes can be completely disentangled under the expected utility theorem (EUT) by modeling each of them successively in two steps. The conventional form is nested as a special case where the functions
Tourism Economics, 2017
Business tourism has brought significant benefits to New Zealand’s tourism industry and economy. ... more Business tourism has brought significant benefits to New Zealand’s tourism industry and economy. This study aims to provide a better understanding of the impact of economic uncertainty on New Zealand’s business tourism. The panel data gravity model and the maximally correlated portfolio are used to investigate the impacts of economic policy uncertainty (EPU) indices of New Zealand and its key trading partners, along with tourism and aviation-related factors, on New Zealand’s business tourist flows from 2008 to 2015. The findings suggest that two economic factors (New Zealand’s EPU index and bilateral trade volumes) and two noneconomic factors (flying distance and total direct flight seats) are statistically significant in explaining some of the variations in business tourism flows. The results have important policy implications for New Zealand’s policymakers in understanding business visitor demands and planning their tourism strategies.
Journal of Economic Behavior & Organization, 2017
This paper considers "soft debt" as a social convention that facilitates long-term reciprocal rel... more This paper considers "soft debt" as a social convention that facilitates long-term reciprocal relationships. A player is said to follow a soft debt strategy if his decisions depend on the entire history with his counterpart only through their accrued soft debt balance. Under discrete benefits, there exist equilibria in which the players keep reciprocating as long as the debt balance does not exceed a certain limit.
Design of a single layer programmable Structured ASIC library
13th IEEE Symposium on Design and Diagnostics of Electronic Circuits and Systems, 2010
... Issue Date: 2010. Citation: CHAU CP Thomas, LEONG PH W, HO Man HO, CHAN Pui Wai, YUEN Chi Lap... more ... Issue Date: 2010. Citation: CHAU CP Thomas, LEONG PH W, HO Man HO, CHAN Pui Wai, YUEN Chi Lap, PUN Kong Pang, CHOY Chiu Sing Oliver, WU Yu Liang. 13th IEEE International Symposium on Design and Diagnosis of Electronic Circuits and Systems, 2010, p.. ...
2010 15th Asia and South Pacific Design Automation Conference (ASP-DAC), 2010
2017 IEEE International Conference on Robotics and Automation (ICRA), 2017
This paper presents preliminary results of the design, development, and evaluation of a hand reha... more This paper presents preliminary results of the design, development, and evaluation of a hand rehabilitation glove fabricated using lobster-inspired hybrid design with rigid and soft components for actuation. Inspired by the bending abdomen of lobsters, hybrid actuators are built with serially jointed rigid shells actuated by pressurized soft chambers inside to generate bending motions. Such bio-inspiration absorbs features from the classical rigid-bodied robotics with preciselydefined motion generation, as well as the emerging soft robotics with lightweight , physically safe, and adaptive actuation. The fabrication procedure is described, followed by experiments to mechanically characterize these actuators. Finally, an openpalm glove design integrated with these hybrid actuators are presented for a qualitative case study. A hand rehabilitation system is developed by learning patterns of the sEMG signals from the users forearm to train the assistive glove for hand rehabilitation exercises.
Lobster-inspired hybrid actuator
2017 IEEE International Conference on Robotics and Automation (ICRA), 2017
Classical rigid-bodied robotic systems are presented with proven success in theoretical developme... more Classical rigid-bodied robotic systems are presented with proven success in theoretical development and industrial applications, are recently challenged by the emergence of soft robotics due to a growing need in physical human-robot interactions (pHRI), such as wearable devices, medical robots, personal robots, etc. In this paper, we present the design and fabrication of a robust, hybrid bending actuator build from both rigid and soft components inspired by crustaceans, where its bending radius and axis can be mechanically programmed through the selective activation of the rigid exterior joints, actuated by the soft actuators inside. The hybrid actuator was experimentally measured in terms of bending and force tests to demonstrate the utility of this design. Finally, a case study was presented to demonstrate its capacity to adapt to specific objects geometry, anticipating its potential application in situations where compliance is the priority.