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Visual analysis tasks, including crowd management, often require resource-intensive machine learning models, posing challenges for deployment on edge hardware. Consequently, cloud computing emerges as a prevalent solution. To address privacy concerns associated with offloading video data to remote cloud platforms, we present a novel approach using adversarial training to develop a lightweight obfuscator neural network. Our method focuses on pedestrian detection as an example of visual analysis, allowing the transformation of video frames on the camera itself to retain only essential information for pedestrian detection while preserving privacy. Importantly, the obfuscated data remains compatible with publicly available object detectors, requiring no modifications or significant loss in accuracy. Additionally, our technique overcomes the common limitation of relying on labeled sensitive attributes for privacy preservation. By demonstrating the inability of pedestrian attribute recognition models to detect attributes in obfuscated videos, we validate the efficacy of our privacy protection method. Our results suggest that this scalable approach holds promise for enabling camera usage in video analytics while upholding personal privacy. [ABSTRACT FROM AUTHOR]

Two capacitive sensing units were designed, fabricated, and embedded into two corresponding fingerstalls through microelectronic and additive manufacturing with flexible materials and ergonomic considerations in this study. The sensing units were routed to an adaptor, which in turn was routed to a transmission port (comprising a signal converter and a Bluetooth module), realizing a wearable and wireless force sensing system for sports science applications as the objective. The collected capacitive signals were converted through a preliminarily established database, indicating local force distributions on finger segments. Practical examinations with badminton actions (forehand cross-net shots) were conducted by players to show the effectiveness of the proposed system as an application example. Statistical and quantified results reflected the visual observations on valid shots (67% and 39% for the professional and amateur players, respectively) and well-controlled racket-holding attitude (19.69% and 35.31% force application difference between the first two segments of the index finger of the professional and amateur player, respectively). These proved that the proposed system outperforms existing similar systems in the market and is able to not only classify players with different skill levels but also distinguish attitude stability and controllability, showing scientific evidence in sports science for the first time. [ABSTRACT FROM AUTHOR]

The present study aimed to explore the value of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in differentiating hepatocellular carcinoma (HCC) from intrahepatic cholangiocarcinoma (ICC). This study included 65 patients with malignant hepatic nodules (55 with HCC, 10 with ICC), and 17 control patients with normal livers. All patients underwent IVIM-DWI scans on a 3.0 T magnetic resonance imaging (MRI) scanner. The standard apparent diffusion coefficient (ADC), pure diffusion coefficient (Dslow), pseudo-diffusion coefficient (Dfast), and perfusion fraction (f) were obtained. Differences in the parameters among the groups were analysed using one-way ANOVA, with p < 0.05 indicating statistical significance. Receiver operating characteristic (ROC) curve analysis was used to compare the efficacy of each parameter in differentiating HCC from ICC. ADC, Dslow, Dfast, f significantly differed among the three groups. ADC and Dslow were significantly lower in the HCC group than in the ICC group, while Dfast was significantly higher in the HCC group than in the ICC group; f did not significantly differ between the HCC and ICC groups. When the cut-off values of ADC, Dslow, and Dfast were 1.27 × 10−3 mm2/s, 0.81 × 10−3 mm2/s, and 26.04 × 10−3 mm2/s, respectively, their diagnostic sensitivities for differentiating HCC from ICC were 98.18%, 58.18%, and 94.55%, their diagnostic specificities were 50.00%, 80.00%, and 80.00%, and their areas under the ROC curve (AUCs) were 0.687, 0.721, and 0.896, respectively. Dfast displayed the largest AUC value. IVIM-DWI can be used to differentiate HCC from ICC. [ABSTRACT FROM AUTHOR]

The flow behavior of the shielding gas has been a key factor to improve the quality of products manufactured by the selective laser melting (SLM) technology as it is a major mechanism to remove the ejected metal particles away from the working plane. In this study, to obtain a proper flow field, computational fluid dynamics (CFD) with the application of the Taguchi method was employed to investigate the flow field across the working chamber, with the variations in the geometries of the blowing nozzle, the widths of the suction tunnel, the suction-to-plane distances, and the Reynolds numbers of the blowing flow. The simulation was first verified with experimental measurements. The ejecting motions of the metal powders were also taken into consideration to study the interactions between the shielding gas and the ejected particles. The results demonstrated that axis switching as well as the suction-to-plane distance are the important factors for improving the particle removal efficiency during the SLM operation. [ABSTRACT FROM AUTHOR]

This work proposes second-order and fourth-order versions of a Cartesian grid based kernel-free boundary integral (KFBI) method for the biharmonic equation on both bounded irregular domains and singly periodic irregular domains. It is further development of the previous KFBI method for second-order elliptic PDEs. It reformulates boundary value problems of the fourth-order PDE as boundary integral equations of the first kind but the solution never needs to know the fundamental solution or Green's function of the elliptic operator. Evaluation of boundary or volume integrals in the solution of boundary integral equations is made by solving equivalent interface problems on Cartesian grids with standard finite difference methods and fast Fourier transform based solvers. The work decomposes the biharmonic equation into two Poisson equations. It assumes the solution to one Poisson equation, which has no boundary conditions, as the sum of a volume integral with a double layer boundary integral, and applies Green's third identity to derive a scalar boundary integral equation from the other Poisson equation that are subject to two boundary conditions. In the solution of the scalar boundary integral equation, each volume or boundary integral is evaluated with the KFBI method. Numerical examples are presented to demonstrate the solution accuracy and algorithm efficiency. A remarkable point of the work is that the nine-point compact difference scheme in dealing with each split second-order elliptic interface problem on irregular domains yields fourth-order accurate solution for the biharmonic equation. [ABSTRACT FROM AUTHOR]

The heat transfer mechanism during laminar cooling before the down coiler of the run-out-table (ROT) process is a metallurgical key for maintaining the quality of the steel strip. Large variation of the temperature profile along the strip forms residual stress, resulting in the strip distortion. This study developed a computational model through the commercial software Simufact™ to analyze the temperature history and deformation, for the purpose of precisely predicting the behaviors of phase transformation during laminar cooling on ROT. This model simulated a specific case, HM690T, provided by the steel factory of which the mechanical properties are computed through JMatPro™. The model was first verified in accordance with the field data of temperature profile and experimental measurements of residual stress obtained from the steel company, based on the cooling process provided by the top and bottom water banks. The simulation model was then applied to predict the deformations at each cooling stage and the secondary deformations resulted from alternative cooling of water and air. In addition, the stresses, deformation, and phase transformation for various cooling patterns and cooling periods were simulated based on the developed model, and the optimal ratio of cooling periods of the top and bottom banks was determined. The analysis helps solve the problem of strip flatness during cooling stage on ROT. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) as a part of 3D printing technology has been a novel industrial manufacturing process nowadays. However, the collection of metal powders emitted from the working plane is significant for the SLM process. The uniformity of the flow passing through the SLM working chamber, which helps collect emitted powders, has been considered as a key solution. In this study, for the purpose of improving the flow uniformity, a blow-to-suction device composed of a trapezoid push nozzle, a working chamber, and a suction tunnel was applied. Various parameters, such as the width of trapezoid push nozzle, the width of suction tunnel, and the nozzle-to-plane distances, were examined experimentally and computationally. Hot-wire velocity measurement and smoke flow visualization were used to verify the reliability of the simulation. Through the results of degree of uniformity (DOU), the momentum exchange between the suction and blow sides plays an important role for producing a uniform flow through the working chamber. In addition, higher suction velocity as well as larger nozzle-to-plane distance result in relatively better uniformity of the flow. [ABSTRACT FROM AUTHOR]

In Taiwan, due to the limited capacity of waste cooking oil, palm oil has been viewed as the potential low-cost imported feedstock for producing biodiesel, in the way of obtaining oil feedstock in Malaysia and producing biodiesel in Taiwan. This study aims to evaluate the cradle-to-grave life cycle environmental performance of palm biodiesel within two different Asian countries, Malaysia and Taiwan. The phases of the life cycle such as direct land-use-change impact, plantation and milling are investigated based on the Malaysia case and those of refining, and fuel production as well as engine combustion is based on Taiwan case. The greenhouse gas (GHG) emission and energy consumption for the whole life cycle were calculated as −28.29 kg CO-equiv. and +23.71 MJ/kg of palm-derived biodiesel. We also analyze the impacts of global warming potential (GWP) and the payback time for recovering the GHG emissions when producing and using biodiesel. Various scenarios include (1) clearing rainforest or peat-forest; (2) treating or discharging palm-oil-milling effluent (POME) are further developed to examine the effectiveness of improving the environmental impacts [ABSTRACT FROM AUTHOR]

Investigating laminar separation over the turbine blade of a horizontal-axis wind turbine (HAWT) has been considered an important task to improve the aerodynamic performance of a wind turbine. To better understand the laminar separation phenomena, in this study, the aerodynamic forces of a SD8000 airfoil (representing the sectional blade shape) in the steady-state conditions were first predicted using an incompressible Reynolds-averaged Navier-Stokes solver with the γ- Re and k- k - ω transition models. By comparing simulation and experimental results, the k- k - ω transition model was chosen to simulate the laminar separation on three-dimensional (3D) turbine blade. Experimentally, a HAWT with three blades was then tested in a close-circuit wind tunnel between the tip speed ratios (TSRs) of 2 and 7 at the wind speed of 10 m/s. In addition, through computational fluid dynamics, the turbine performance and flow characteristics on the blade as blade is rotating were investigated. It is shown that 3D simulations agreed well with the experimental results with regard to the mechanical power of the HAWT at the testing TSRs. Moreover, the separation and reattachment lines on the suction surface of the turbine blade were also observed through the skin friction line, indicating that laminar separation moved toward the trailing edge with the increasing TSR at the blade tip region. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to develop a small-scale horizontal-axis wind turbine (HAWT) suitable for the local wind conditions of Tainan, Taiwan. The wind energy potential was first determined through the Weibull wind speed distribution and then was adapted to the design of the turbine blade. Two numerical approaches were adopted in the design and analysis of the HAWT turbine blades. The blade element momentum theory (BEMT) was used to lay out the shape of the turbine blades (S822 and S823 airfoils). The geometry of the root region of the turbine blade was then modified to facilitate integration with a pitch control system. A mathematical model for the prediction of aerodynamic performance of the S822 and S823 airfoils, in which the lift and drag coefficients are calculated using BEMT equations, was then developed. Finally, computational fluid dynamics (CFD) was used to examine the aerodynamic characteristics of the resulting turbine blades. The resulting aerodynamic performance curves obtained from CFD simulation are in agreement with those obtained using BEMT. It is also observed that separation flow occurred at the turbine blade root at the tip speed ratios of 5 and 7. [ABSTRACT FROM AUTHOR]

We report x-ray absorption near edge structure (XANES) on bulk samples of CaGdMnO with x = 0, 0.02, and 0.05. The transport properties measurements indicate that both resistivity and the absolute value of thermopower decrease with increasing x. Meanwhile, the temperature dependence of resistivity changes from non-metallic CaMnO to metallic for samples of x = 0.02 and 0.05. XANES spectra at the O K-edge, Mn L-edge, and Ca L-edge indicate that Mn 3 d-O 2 p hybridization increases considerably, and unoccupied (3 d-4 s) states of Ca decrease with increasing substitution content. The increases of Mn 3 d-O 2 p hybridization might be responsible for the decrease of the resistivity and the absolute value of thermopower upon partial Gd substitution for Ca. [ABSTRACT FROM AUTHOR]