1,651 research outputs found
Smart technology for healthcare: Exploring the antecedents of adoption intention of healthcare wearable technology
© The Author(s), 2019. Technological advancement and personalized health information has led to an increase in people using and responding to wearable technology in the last decade. These changes are often perceived to be beneficial, providing greater information and insights about health for users, organizations and healthcare and government. However, to date, understanding the antecedents of its adoption is limited. Seeking to address this gap, this cross-sectional study examined what factors influence users’ adoption intention of healthcare wearable technology. We used self-administrated online survey to explore adoption intentions of healthcare wearable devices in 171 adults residing in Hong Kong. We analyzed the data by Partial least squares – structural equation modelling (PLS-SEM). The results reveal that perceived convenience and perceived irreplaceability are key predictors of perceived useful ness, which in turn strengthens users’ adoption intention. Additionally, the results also reveal that health belief is one of the key predictors of adoption intention. This paper contributes to the extant literature by providing understanding of how to strengthen users’ intention to adopt healthcare wearable technology. This includes the strengthening of perceived convenience and perceived irreplaceability to enhance the perceived usefulness, incorporating the extensive communication in the area of healthcare messages, which is useful in strengthening consumers’ adoption intention in healthcare wearable technology
Race and the Victim: An Examination of Capital Sentencing and Guilt Attribution Studies
This article examines the effect of the race of the victim on legal decision making in capital and non-capital criminal cases. A large body of research on race and capital sentencing indicates that the crime victim\u27s race affects the prosecutor\u27s decision to seek, and the jury\u27s decision to recommend, the death penalty. The most well known of these is undoubtedly the Baldus study, which provided the data underlying the defendant\u27s challenge to the Georgia death penalty regime in McCleskey v. Kemp. Less well known are empirical analyses conducted since the Supreme Court rejected McCleskey\u27s challenge. The article reviews several of these studies, virtually all of which find the victim\u27s race continues to matter to death penalty sentencing. The author also reviews the results of experiments on jury decisionmaking in non-capital cases, which reach conflicting results on the significance of juror-victim racial similarity and guilt attribution. Although an experimental design allows researchers to hold constant every variable other than race, the juries in these experiments often differ significantly from real world juries, thereby limiting the confidence one may have in the applicability of those results outside the laboratory. The article concludes by noting where additional study would be useful
Large Extra Dimensions at Linear Colliders
In this talk, I first present the motivation for theories wherein extra
spacetime dimensions can be compactified to have large magnitudes. In
particular, I discuss the Arkani-Hamed, Dimopoulos, Dvali (ADD) scenario. I
present the constraints that have been derived on these models from current
experiments and the expectations from future colliders. I concentrate
particularly on the possibilities of probing these extra dimensions at future
linear colliders.Comment: Talk given at the Third International Workshop on Electron-Electron
Interactions at TeV Energies (e- e- 99), Santa Cruz, California, 10-12 Dec
1999. 7 pages, LaTeX, style files attache
Optical properties of the pseudogap state in underdoped cuprates
Recent optical measurements of deeply underdoped cuprates have revealed that
a coherent Drude response persists well below the end of the superconducting
dome. In addition, no large increase in optical effective mass has been
observed, even at dopings as low as 1%. We show that this behavior is
consistent with the resonating valence bond spin-liquid model proposed by Yang,
Rice, and Zhang. In this model, the overall reduction in optical conductivity
in the approach to the Mott insulating state is caused not by an increase in
effective mass, but by a Gutzwiller factor, which describes decreased coherence
due to correlations, and by a shrinking of the Fermi surface, which decreases
the number of available charge carriers. We also show that in this model, the
pseudogap does not modify the low-temperature, low-frequency behavior, though
the magnitude of the conductivity is greatly reduced by the Gutzwiller factor.
Similarly, the profile of the temperature dependence of the microwave
conductivity is largely unchanged in shape, but the Gutzwiller factor is
essential in understanding the observed difference in magnitude between ortho-I
and -II YBaCuO.Comment: 9 pages, 6 figures, submitted to Eur. Phys. J.
Dynamic behavior investigations and disturbance rejection predictive control of solvent-based post-combustion CO2 capture process
Increasing demand for flexible operation has posed significant challenges to the control system design of solvent-based post-combustion CO2 capture (PCC) process: 1) the capture system itself has very slow dynamics; 2) in the case of wide range of operation, dynamic behavior of the PCC process will change significantly at different operating points; and 3) the frequent variation of upstream flue gas flowrate will bring in strong disturbances to the capture system. For these reasons, this paper provides a comprehensive study on the dynamic characteristics of the PCC process. The system dynamics under different CO2 capture rates, re-boiler temperatures, and flue gas flow rates are analyzed and compared through step-response tests. Based on the in-depth understanding of the system behavior, a disturbance rejection predictive controller (DRPC) is proposed for the PCC process. The predictive controller can track the desired CO2 capture rate quickly and smoothly in a wide operating range while tightly maintaining the re-boiler temperature around the optimal value. Active disturbance rejection approach is used in the predictive control design to improve the control property in the presence of dynamic variations or disturbances. The measured disturbances, such as the flue gas flow rate, is considered as an additional input in the predictive model development, so that accurate model prediction and timely control adjustment can be made once the disturbance is detected. For unmeasured disturbances, including model mismatches, plant behavior variations, etc., a disturbance observer is designed to estimate the value of disturbances. The estimated signal is then used as a compensation to the predictive control signal to remove the influence of disturbances. Simulations on a monoethanolamine (MEA) based PCC system developed on gCCS demonstrates the excellent effect of the proposed controller
Reinforced coordinated control of coal-fired power plant retrofitted with solvent based CO2 capture using model predictive controls
Solvent-based post-combustion CO2 capture (PCC) provides a promising technology for the CO2 removal of coal-fired power plant (CFPP). However, there are strong interactions between the CFPP and the PCC system, which makes it challenging to attain a good control for the integrated plant. The PCC system requires extraction of large amounts of steam from the intermediate/low pressure steam turbine to provide heat for solvent regeneration, which will reduce power generation. Wide-range load variation of power plant will cause strong fluctuation of the flue gas flow and brings in a significant impact on the PCC system. To overcome these issues, this paper presents a reinforced coordinated control scheme for the integrated CFPP-PCC system based on the investigation of the overall plant dynamic behavior. Two model predictive controllers are developed for the CFPP and PCC plants respectively, in which the steam flow rate to re-boiler and the flue-gas flow rate are considered as feed-forward signals to link the two systems together. Three operating modes are considered for designing the coordinated control system, which are: (1) normal operating mode; (2) rapid power load change mode; and (3) strict carbon capture mode. The proposed coordinated controller can enhance the overall performance of the CFPP-PCC plant and achieve a flexible trade-off between power generation and CO2 reduction. Simulation results on a small-scale subcritical CFPP-PCC plant developed on gCCS demonstrates the effectiveness of the proposed controller
Flexible operation of supercritical coal-fired power plant integrated with solvent-based CO2 capture through collaborative predictive control
This paper presents a controller design study for the supercritical coal fired power plant (CFPP) integrated with solvent-based post-combustion CO2 capture (PCC) system. The focus of the study is on the steam drawn-off from turbine to the re-boiler, which is the key interaction between the CFPP and PCC plants. The simulation study of a 660 MW supercritical CFPP-PCC unit model has shown that the impact of re-boiler steam change on the power generation of CFPP is more than 100 times faster than that on the PCC operation. Considering this finding, a collaborative predictive control strategy is proposed for the CFPP-PCC system where the re-boiler steam flowrate is manipulated for the CFPP load ramping and then gradually set to the required value for CO2 capture. The PCC is thereby exploited as an energy storage device, which can quickly store/release extra energy for the CFPP in addition to the primary function of carbon emission reduction. The simulation results show that the proposed collaborative predictive controller can effectively improve the load ramping performance of CFPP without much performance degradation on the PCC operation
Higher Derivative Operators from Scherk-Schwarz Supersymmetry Breaking on T^2/Z_2
In orbifold compactifications on T^2/Z_2 with Scherk-Schwarz supersymmetry
breaking, it is shown that (brane-localised) superpotential interactions and
(bulk) gauge interactions generate at one-loop higher derivative counterterms
to the mass of the brane (or zero-mode of the bulk) scalar field. These
brane-localised operators are generated by integrating out the bulk modes of
the initial theory which, although supersymmetric, is nevertheless
non-renormalisable. It is argued that such operators, of non-perturbative
origin and not protected by non-renormalisation theorems, are generic in
orbifold compactifications and play a crucial role in the UV behaviour of the
two-point Green function of the scalar field self-energy. Their presence in the
action with unknown coefficients prevents one from making predictions about
physics at (momentum) scales close to/above the compactification scale(s). Our
results extend to the case of two dimensional orbifolds, previous findings for
S^1/Z_2 and S^1/(Z_2 x Z_2') compactifications where brane-localised higher
derivative operators are also dynamically generated at loop level, regardless
of the details of the supersymmetry breaking mechanism. We stress the
importance of these operators for the hierarchy and the cosmological constant
problems in compactified theories.Comment: 23 pages, LaTeX, one figure, published version in JHE
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