Search

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have emerged as a promising therapy for diabetes and CKD patients. However, the pros and cons of SGLT2i in Type2 diabetes patients with CKD stage 5 remained largely unexplored. By using Taiwan's national health insurance research database (NHIRD), this observational cohort study enrolled T2DM patients with newly identified as having CKD5, and the index date defined as the date of CKD5 identification. The enrollees were divided into 2 groups depending on whether SGLT2 inhibitors were used for more than 3 months or not following the index date. A 1:4 propensity score matching was performed to balance characteristics between two groups. The SGLT2-inhibitor group exhibited significantly lower risks of new-onset ESRD (35.9% vs. 58.2%, hazard ratio [HR] 0.59, 95% confidence interval [CI]: 0.59–0.74). For the risks of MACCEs (16.72% vs. 17.66%, HR 0.84, 95% CI: 0.62–1.15), infections related hospitalization (2.4% vs. 2.61%, HR:1.02, 95% CI:0.80–1.31), Infection-associated mortality (3.45% vs. 4.18% HR:0.80, 95% CI:0.41–1.56) and all-cause mortality (13.79% vs. 13.83%, HR:0.95, 95% CI:0.68–1.32), no significant differences were observed between two groups. In conclusion, we provide evidence suggesting that SGLT2 inhibitors may offer renal protection and did not increase infection risks for CKD5 patients with type2 diabetes. [ABSTRACT FROM AUTHOR]

Public libraries are an invaluable institution in the United States, and the digital revolution has posed many challenges for them. With the American Library Association's updated "Library Bill of Rights" and public library services increasingly moving online in response to the COVID-19 pandemic, the protection of patron privacy in public libraries is an important and timely topic of study. However, there is a lack of empirical data regarding privacy practices and the challenges that public libraries face. To fill this gap, we conducted an online survey that was sent to more than 12,500 public librarians across the country to study the state of patron privacy practices and challenges in public libraries. This study is the first of its kind on this topic. Our results show that patron privacy protections vary drastically depending on the library's size and service area. This study provides essential knowledge for administrators and policy makers in public libraries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic hepatitis B and C infections are major causes of morbidity and mortality in end-stage kidney disease (ESKD) patients on hemodialysis (HD). The Fibrosis-4 (FIB-4) score is a non-invasive method to evaluate chronic liver disease. However, it is unclear whether there is a connection between the FIB-4 score and major adverse cardiovascular events (MACEs) and mortality in patients on HD. This study investigates the relationship between FIB-4 scores, MACEs, and mortality in HD patients. METHODS: A 5-year retrospective study included 198 HD patients with chronic hepatitis B and C from Chang Gung Memorial Hospital. FIB-4 scores were categorized into high (>2.071), middle (1.030~2.071), and low (<1.030) tertiles for cross-sectional analyses. MACEs and mortality were tracked longitudinally. RESULTS: Patients with high FIB-4 scores had lower hemoglobin and albumin levels. Cox multivariate analysis showed that high FIB-4 scores (aHR: 1.589) and diabetes mellitus (aHR: 5.688) were significant factors for all-cause mortality. The optimal FIB-4 score for 5-year mortality was 2.942. FIB-4 scores were not significant for predicting 5-year MACEs. CONCLUSIONS: High FIB-4 scores are associated with increased 5-year all-cause mortality risk in HD patients with chronic hepatitis virus infection. [ABSTRACT FROM AUTHOR]

Public libraries serve as crucial resources for the public to access information, with the safeguarding of patrons’ privacy being a longstanding and essential mission. This study builds on a previous survey that delved into the perspectives of public librarians and administrators on patron privacy protection. Our specific goal in this study was to identify the practices employed by Information Technology (IT) professionals and the challenges they face in safeguarding patrons’ privacy within public libraries. Conducting a comprehensive focus group study involving 33 IT professionals across 10 sessions, we sought to gain insights into their experiences and perspectives on protecting patrons’ privacy. Our findings reveal that IT professionals express concerns about patrons’ lack of awareness regarding the significance of privacy protection, placing staff in the challenging position of balancing convenient customer service with the imperative to protect patron privacy. Moreover, a notable challenge faced by IT professionals in libraries is the lack of training and technical knowledge among library staff to optimize technologies for ensuring patrons’ privacy. The study also highlights IT professionals’ reservations about the collection of patrons’ data by libraries or vendors, prompting a desire for a deeper understanding of both technical and nontechnical measures to enhance privacy protection. While our research sheds light on the concerns and practices of library IT professionals, we believe the insights gained can provide library administrators and policymakers to gauge the critical role of technology in privacy protection. By understanding these challenges, policymakers can modify and implement policies and practices to effectively enhance the protection of patrons’ privacy in public libraries. [ABSTRACT FROM AUTHOR]

Different from other high cardiovascular (CV) risks populations, the evidence supporting the CV protective effect of LDL-C reduction with statins in chronic kidney disease (CKD) patients is comparatively scarce. This study is aimed to investigate the role of maintaining lower LDL-C level in advanced CKD patients. By using Chang Gung Research Database, on the basis of Taiwan's largest healthcare group, a total of 5367 adult patients newly-diagnosed with stage 4 CKD and receiving statin were extracted and further categorized into three groups based on their LDL-C levels: <70 mg/dL, 70–100 mg/dL, and ≥100 mg/dL. The main outcome is major adverse cardiac and cerebrovascular events (MACCEs), a composite of cardiovascular death, myocardial infarction, and stroke. The inverse probability of treatment weighting was performed to achieve balance of baseline characteristics. At 5-year follow-up, the LDL-C < 70 mg/dL group exhibited significantly lower risks of MACCEs (14.3 % vs. 18.7 %, hazard ratio [HR]: 0.77, 95 % CI: 0.69–0.86), cardiovascular death (7.1 % vs. 9.7 %, subdistribution HR [SHR]: 0.75, 95 % CI: 0.65–0.88), ischemic stroke (4.1 % vs. 5.4 %, [SHR]: 0.65, 95 % CI: 0.54–0.79), and new-onset end-stage renal disease requiring chronic dialysis (25.6 % vs. 29.4 %, SHR: 0.87, 95 % CI: 0.80–0.91) compared to LDL-C > 100 mg/dL group. In contrast, the group with LDL-C levels between 70 and 100 did not significantly differ from the group with LDL-C > 100 mg/dL in study outcomes. Maintaining LDL-C lower than 70 mg/dL may be beneficial for cardiovascular protection in advanced CKD patients and a lower LDL-C treatment target may be required as CKD progression. [Display omitted] • No direct evidence is available from randomized control trials to support the current target LDL-C levels in patients with different CKD stages. • This cohort study suggests that statin users with LDL-C < 70 mg/dL have relatively favorable 5-year CV and renal outcomes in advanced CKD patients. • LDL-C at lower levels may be beneficial for CV protection as CKD progression; however, further randomized control trials are warranted. [ABSTRACT FROM AUTHOR]

In recent years, unmanned aerial vehicles (UAVs) have been applied in many fields owing to their mature flight control technology and easy-to-operate characteristics. No doubt, these UAV-related applications rely heavily on location information provided by the positioning system. Most UAVs nowadays use a global navigation satellite system (GNSS) to obtain location information. However, this outside-in 3rd party positioning system is particularly susceptible to environmental interference and cannot be used in indoor environments, which limits the application diversity of UAVs. To deal with this problem, in this paper, a stereo-based visual simultaneous localization and mapping technology (vSLAM) is applied. The presented vSLAM algorithm fuses onboard inertial measurement unit (IMU) information to further solve the navigation problem in an unknown environment without the use of a GNSS signal and provides reliable localization information. The overall visual positioning system is based on the stereo parallel tracking and mapping architecture (S-PTAM). However, experiments found that the feature-matching threshold has a significant impact on positioning accuracy. Selection of the threshold is based on the Hamming distance without any physical meaning, which makes the threshold quite difficult to set manually. Therefore, this work develops an online adaptive matching threshold according to the keyframe poses. Experiments show that the developed adaptive matching threshold improves positioning accuracy. Since the attitude calculation of the IMU is carried out based on the Mahony complementary filter, the difference between the measured acceleration and the gravity is used as the metric to online tune the gain value dynamically, which can improve the accuracy of attitude estimation under aggressive motions. Moreover, a static state detection algorithm based on the moving window method and measured acceleration is proposed as well to accurately calculate the conversion mechanism between the vSLAM system and the IMU information; this initialization mechanism can help IMU provide a better initial guess for the bundle adjustment algorithm (BA) in the tracking thread. Finally, a performance evaluation of the proposed algorithm is conducted by the popular EuRoC dataset. All the experimental results show that the developed online adaptive parameter tuning algorithm can effectively improve the vSLAM accuracy and robustness. [ABSTRACT FROM AUTHOR]

This article explores how mindfulness-based interventions (MBIs) are applicable to practicing Muslims in the U.S. who are seeking mental health treatment. A close comparison of the mindfulness approach and Islamic tenets indicates that the mindfulness techniques of consciousness, mindful observation, acting with awareness, intention, acceptance, positive reframing, and cognitive reflection are applicable to practicing Muslim clients, because these techniques share core similarities with their religious coping strategies. However, some mindfulness techniques, such as accepting one's psychological problem without judgment and drawing on one's own wisdom to address psychological problems may be challenging for practicing Muslims due to conflicts with their religious beliefs and coping strategies. Based on the review of religious compatibility and empirical studies on the efficacy of MBIs, this article explores how MBIs can be best adapted for Muslim clients based on the clients' religiosity and individual preference. In addition, this article includes specific religious considerations for four programs: Mindfulness-Based Stress Reduction, Mindfulness-Based Cognitive Therapy, Mindfulness-Based Relapse Prevention (MBRP), and Dialectical Behavior Therapy (DBT). With religious adaptations, MBIs can work in tandem with Muslim clients' religious beliefs and coping strategies, and possibly increase clients' likelihood to invest in and adhere to MBIs and effectively improve their mental health. [ABSTRACT FROM AUTHOR]

The choriocapillaris (CC) plays an essential role in maintaining the normal functions of the human eye. There is increasing interest in the community to develop an imaging technique for visualizing the CC, yet this remains underexplored due to technical limitations. We propose an approach for the visualization of the CC in humans via a complex signal-based optical microangiography (OMAG) algorithm, based on commercially available spectral domain optical coherence tomography (SD-OCT). We show that the complex signal-based OMAG was superior to both the phase and amplitude signal-based approaches in detailing the vascular lobules previously seen with histological analysis. With this improved ability to visualize the lobular vascular networks, it is possible to identify the feeding arterioles and draining venules around the lobules, which is important in understanding the role of the CC in the pathogenesis of ocular diseases. With built-in FastTrac™ and montage scanning capabilities, we also demonstrate wide-field SD-OCT angiograms of the CC with a field of view at 9 × 11 mm2 [ABSTRACT FROM AUTHOR]

In the new-generation wearable Electrocardiogram (ECG) system, signal processing with low power consumption is required to transmit data when detecting dangerous rhythms and to record signals when detecting abnormal rhythms. The QRS complex is a combination of three of the graphic deflection seen on a typical ECG. This study proposes a real-time QRS detection and R point recognition method with low computational complexity while maintaining a high accuracy. The enhancement of QRS segments and restraining of P and T waves are carried out by the proposed ECG signal transformation, which also leads to the elimination of baseline wandering. In this study, the QRS fiducial point is determined based on the detected crests and troughs of the transformed signal. Subsequently, the R point can be recognized based on four QRS waveform templates and preliminary heart rhythm classification can be also achieved at the same time. The performance of the proposed approach is demonstrated using the benchmark of the MIT-BIH Arrhythmia Database, where the QRS detected sensitivity (Se) and positive prediction (+P) are 99.82% and 99.81%, respectively. The result reveals the approach's advantage of low computational complexity, as well as the feasibility of the real-time application on a mobile phone and an embedded system. [ABSTRACT FROM AUTHOR]

OCT has revolutionized the practice of ophthalmology over the past 10-20 years. Advances in OCT technology have allowed for the creation of novel OCT-based methods. OCT-Angiography (OCTA) is one such method that has rapidly gained clinical acceptance since it was approved by the FDA in late 2016. OCTA images are based on the variable backscattering of light from the vascular and neurosensory tissue in the retina. Since the intensity and phase of backscattered light from retinal tissue varies based on the intrinsic movement of the tissue (e.g. red blood cells are moving, but neurosensory tissue is static), OCTA images are essentially motion-contrast images. This motion-contrast imaging provides reliable, high resolution, and non-invasive images of the retinal vasculature in an efficient manner. In many cases, these images are approaching histology level resolution. This unprecedented resolution coupled with the simple, fast and non-invasive imaging platform have allowed a host of basic and clinical research applications. OCTA demonstrates many important clinical findings including areas of macular telangiectasia, impaired perfusion, microaneurysms, capillary remodeling, some types of intraretinal fluid, and neovascularization among many others. More importantly, OCTA provides depth-resolved information that has never before been available. Correspondingly, OCTA has been used to evaluate a spectrum of retinal vascular diseases including diabetic retinopathy (DR), retinal venous occlusion (RVO), uveitis, retinal arterial occlusion, and age-related macular degeneration among others. In this review, we will discuss the methods used to create OCTA images, the practical applications of OCTA in light of invasive dye-imaging studies (e.g. fluorescein angiography) and review clinical studies demonstrating the utility of OCTA for research and clinical practice. [ABSTRACT FROM AUTHOR]

Background: Schizophrenia is a neurological disease characterized by alterations to patients' cognitive functions and emotional expressions. Relevant studies often use magnetic resonance imaging (MRI) of the brain to explore structural differences and responsiveness within brain regions. However, as this technique is expensive and commonly induces claustrophobia, it is frequently refused by patients. Thus, this study used non-contact infrared thermal facial images (ITFIs) to analyze facial temperature changes evoked by different emotions in moderately and markedly ill schizophrenia patients. Methods: Schizophrenia is an emotion-related disorder, and images eliciting different types of emotions were selected from the international affective picture system (IAPS) and presented to subjects during ITFI collection. ITFIs were aligned using affine registration, and the changes induced by small irregular head movements were corrected. The average temperatures from the forehead, nose, mouth, left cheek, and right cheek were calculated, and continuous temperature changes were used as features. After performing dimensionality reduction and noise removal using the component analysis method, multivariate analysis of variance and the Support Vector Machine (SVM) classification algorithm were used to identify moderately and markedly ill schizophrenia patients. Results: Analysis of five facial areas indicated significant temperature changes in the forehead and nose upon exposure to various emotional stimuli and in the right cheek upon evocation of high valence low arousal (HVLA) stimuli. The most significant P-value (lower than 0.001) was obtained in the forehead area upon evocation of disgust. Finally, when the features of forehead temperature changes in response to low valence high arousal (LVHA) were reduced to 9 using dimensionality reduction and noise removal, the identification rate was as high as 94.3%. Conclusions: Our results show that features obtained in the forehead, nose, and right cheek significantly differed between moderately and markedly ill schizophrenia patients. We then chose the features that most effectively distinguish between moderately and markedly ill schizophrenia patients using the SVM. These results demonstrate that the ITFI analysis protocol proposed in this study can effectively provide reference information regarding the phase of the disease in patients with schizophrenia. [ABSTRACT FROM AUTHOR]

Lattice Boltzmann simulation of convective heat transfer of non-Newtonian fluids in an impeller stirred tank is performed. The curved and moving boundary methods combined with the unknown-index algorithm are used to solve the flow and thermal fields induced in a cold tank by an oscillating hot impeller. For a given maximum radius of the blades, the simulation results show that a rectangular impeller of large aspect ratio induces stronger heat transfer effect on the tank walls than the small aspect ratio. This is because the latter would cause worse field synergy than the former, i.e. the induced local velocities of fluid are mostly perpendicular to the temperature gradients. The convection effects on the tank walls are also improved as the oscillation amplitude of impeller increases until the swept areas of impeller are close to whole azimuth of the tank, i.e., oscillation amplitude of 90°. The maximum Nusselt number on the tank walls for power-law fluid flows of n = 0.7, 1 and 1.5 occurs at oscillation amplitude of 75°. Finally, it is found that the heat transfer effect on the tank walls is reduced as the power-law index of fluid increases. [ABSTRACT FROM AUTHOR]

Optical coherence tomography angiography (OCTA) has increasingly become a clinically useful technique in ophthalmic imaging. We evaluate the repeatability and reproducibility of blood perfusion in the optic nerve head (ONH) measured using optical microangiography (OMAG)-based OCTA. Ten eyes from 10 healthy volunteers are recruited and scanned three times with a 68-kHz Cirrus HD-OCT 5000-based OMAG prototype system (Carl Zeiss Meditec Inc., Dublin, California) centered at the ONH involving two separate visits within six weeks. Vascular images are generated with OMAG processing by detecting the differences in OCT signals between consecutive B-scans acquired at the same retina location. ONH perfusion is quantified as flux, vessel area density, and normalized flux within the ONH for the prelaminar, lamina cribrosa, and the full ONH. Coefficient of variation (CV) and intraclass correlation coefficient (ICC) are used to evaluate intravisit and intervisit repeatability, and interobserver reproducibility. ONH perfusion measurements show high repeatability [CV ≤ 3.7% (intravisit) and ≤ 5.2% (intervisit)] and interobserver reproducibility (ICC ≤ 0.966) in all three layers by three metrics. OCTA provides a noninvasive method to visualize and quantify ONH perfusion in human eyes with excellent repeatability and reproducibility, which may add additional insight into ONH perfusion in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Design: Cross-sectional, observational study. Subjects: Twenty-eight normal, 30 POAG, and 31 NTG subjects. Methods: One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. Main Outcome Measures: Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH. Results: Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes. Conclusions: Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for diagnosis and monitoring of glaucoma. [ABSTRACT FROM AUTHOR]

This paper performs the lattice Boltzmann simulation combined with unknown-index algorithm for the convective heat transfer problems of an impeller stirred tank. Three types of motion of the heating impeller are adopted in this study, including rotation with constant angular velocity, oscillation and oscillating rotation, which are denoted as Types I, II, and III stirrings respectively. Because the flow structures in rotation stirring case are concentric vertical, the heat transfer efficiency of the tank walls is lower than those of the other two types of stirrings. The other two types of stirrings, the flow structures include complex vortices and present better field synergy of the fluid velocity and temperature gradient, which positively contributes to the convective heat transfer efficiency. The results also indicate that a large swing process angle of the impeller with oscillating rotation stirring does not have significant advantage, because the flow phenomena would be similar to that of constant angular velocity stirring case. Basically, the Type III stirred tank can be considered as an improved Type II stirred tank by choosing appropriate process angle. [ABSTRACT FROM AUTHOR]

In this paper, the lattice Boltzmann method is applied to investigate the natural and mixed convection of Al 2 O 3 /water nanofluids in a square enclosure. The Rayleigh number is considered from 10 3 to 10 6 to present the buoyancy effects. In mixed convection problems, the Richardson number representing the importance of natural convection relative to the forced convection is set to Ri = 1, 5, and 10. Numerical results show that the convective heat transfer effects of nanofluids are higher than that of the base fluid. Increasing the nanoparticle volume fraction up to 4% can cause the averaged Nusselt number of the hot wall an increase about 5–7% in natural convection and 9–13% in mixed convection respectively. In natural convection, the streamlines and temperature contours are found to be slightly changed by adding nanoparticles into water. But in mixed convection, significant differences are obtained because the influence of adding nanoparticles on the properties of nanofluids is enlarged by the force convection effects. [ABSTRACT FROM AUTHOR]

To study the emotional responses of subjects to the International Affective Picture System (IAPS), infrared thermal facial image sequence is preprocessed for registration before further analysis such that the variance caused by minor and irregular subject movements is reduced. Without affecting the comfort level and inducing minimal harm, this study proposes an infrared thermal facial image sequence registration process that will reduce the deviations caused by the unconscious head shaking of the subjects. A fixed image for registration is produced through the localization of the centroid of the eye region as well as image translation and rotation processes. Thermal image sequencing will then be automatically registered using the two-stage genetic algorithm proposed. The deviation before and after image registration will be demonstrated by image quality indices. The results show that the infrared thermal image sequence registration process proposed in this study is effective in localizing facial images accurately, which will be beneficial to the correlation analysis of psychological information related to the facial area. [ABSTRACT FROM AUTHOR]

Numerical simulations are performed to investigate the natural convection heat transfer performance of non-Newtonian power-law fluids in a cavity bounded by wavy vertical walls with different temperatures and flat horizontal walls under adiabatic conditions. The results show that for Rayleigh numbers greater than 10³, the mean Nusselt number has a significantly increase as the flow behavior index is decreased. Moreover, it is shown that in the convection-dominated regime, the mean Nusselt number increases with an increasing Rayleigh number, while in the conduction-dominated regime, the mean Nusselt number remains approximately constant. Finally, it is shown that for a given fluid, the heat transfer performance can be optimized via an appropriate tuning of the wavelength and amplitude of the wavy surface depending on the Rayleigh number. [ABSTRACT FROM AUTHOR]

Abstract: A numerical investigation is performed into the mixed convection heat transfer characteristics of water-based nanofluids confined within a lid-driven cavity. In modeling the cavity, it is assumed that the left and right walls have a wavy surface, while the upper and lower walls are both flat. In addition, it is assumed that the left wavy-wall has a constant heat flux, the right wavy-wall is maintained at a low temperature, and the upper and lower walls are both insulated and move horizontally. The analysis considers three different nanofluids, namely Cu–water, Al2O3–water and TiO2–water. In performing the analysis, the governing equations are modeled using the Boussinesq approximation and are solved numerically using the finite-volume method. The simulations focus on the respective effects of the nanoparticle volume fraction, the type of nanofluid, the Richardson number, the Grashof number and the wavy surface geometry parameters on the mean Nusselt number. The results show that for all considered values of the Richardson number, the mean Nusselt number increases with an increasing volume fraction of nanoparticles. In addition, it is shown that the Cu–water nanofluid yields the best heat transfer performance of the three nanofluids. Furthermore, it is shown that the mean Nusselt number increases with an increasing Grashof number given a constant Richardson number. Finally, the results show that for a given nanofluid, the mean Nusselt number can be optimized via an appropriate tuning of the wavy surface geometry parameters. [Copyright &y& Elsevier]

Abstract: A numerical investigation is performed into the natural convection heat transfer characteristics and entropy generation of water-based nanofluids in an enclosure bounded by wavy vertical walls and flat upper and lower surfaces. In performing the analysis, it is assumed that the left wall is heated by a constant heat flux while the right wall is maintained at a constant low temperature. In addition, the upper and lower walls are both assumed to be insulated. The analysis considers three different nanofluids, namely Cu–water, Al2O3–water and TiO2–water. The governing equations are modeled using the Boussinesq approximation and are solved using the finite-volume numerical method. The analysis examines the effects of the nanoparticle volume fraction, the type of nanofluid, the Rayleigh number and the wavy surface geometry parameters on the mean Nusselt number and total entropy generation. The results show that for all values of the Rayleigh number considered in the present study (Ra =104∼106), the mean Nusselt number increases and the total entropy generation reduces as the volume fraction of nanoparticles increases. In addition, it is shown that the Cu–water nanofluid yields the best heat transfer performance and the lowest total entropy generation of the three nanofluids. Finally, it is shown that for a given nanofluid, the mean Nusselt number can be maximized and the total entropy generation minimized via an appropriate tuning of the wavy surface geometry parameters. Overall, the results presented in this study provide a useful source of reference for enhancing the natural convection heat transfer performance in wavy-wall enclosures while simultaneously reducing the entropy generation. [Copyright &y& Elsevier]

Abstract: This paper analyzes the electroosmotic flow fields in heterogeneous microchannels by applying the lattice Poisson–Boltzmann equation. The influences of surface potential, ionic molar concentration, channel height, and driving force fields on fluid velocity are discussed in detail. A scheme for producing vortexes in a straight channel by adjusting the heterogeneous surface potentials and phase angles of the periodic driving force fields is introduced. By distributing the heterogeneous surface potentials at particular positions, we can create vortexes near walls or in the center of the channel. The size, strength, and rotational direction of vortexes are further variable by introducing appropriate phase angles for a single driving force field or for the phase differences between combined driving force fields, such as electric/pressure fields. These obstacle-like vortexes perturb fluids and hinder flow, and thus, may be useful for enhancing micromixer performance. [Copyright &y& Elsevier]

Rf-sputtered ZnO films, annealed by atmospheric pressure plasma jet (APPJ), are characterized and used for MgZnO/ZnO heterostructures. The highly reactive N2 plasma generated by APPJ allows much shorter treatment time compared with conventional thermal anneals. The APPJ treatment can increase the crystallinity of ZnO films and release the compressive residue stresses, verified by XRD and UV-Vis transmission measurements. In our previous studies, we demonstrate that thermal anneal is the critical step for the formation of two-dimensional electron gases in defective rf-sputtered MgZnO/ZnO heterostructures. This paper reports the experimental results that APPJ treatments can be used for the same purpose with a much shorter processing time. A thirty-second APPJ anneal on ZnO can be used to replace 400 °C × 30 min furnace-anneal to promote the formation of 2DEGs in MgZnO/ZnO heterostructure. The ultra-short processing time is attributed to the synergy of plasma reactivity and temperature of APPJ. [ABSTRACT FROM AUTHOR]

Abstract: A numerical investigation is performed into the flow characteristics of various electrokinetic and pressure-driven flows within microchannels with complex-wavy surfaces. Four different flows are considered, including (1) pure electroosmotic flow; (2) pure pressure-driven flow; (3) combined electroosmotic/pressure-driven flow with a favorable pressure gradient; and (4) combined electroosmotic/pressure-driven flow with an adverse pressure gradient. The effects of the wavy surface geometry parameters and the ratio of the electroosmotic flow velocity to the pressure-driven flow velocity on the fluid flow characteristics are examined. The results show that while flow recirculations are induced by pure pressure-driven flow, recirculation structures are not formed in pure electroosmotic flow. In addition, it is shown that electrokinetically induced velocity is more sensitive than pressure-induced velocity to the waveform geometry. For combined electroosmotic/pressure-driven flow with a favorable pressure gradient, the momentum of the combined flow is sufficient to prevent the formation of flow recirculations. However, for combined electroosmotic/pressure-driven flow with an adverse pressure gradient, flow recirculations are induced near the wave crest when the ratio of the electroosmotic flow velocity to the pressure-driven flow velocity falls below a certain threshold value. It is observed that the recirculation structures are longer and thinner than those that are generated near the wave trough under pure pressure-driven flow conditions. The heat transfer characteristics for various flow scenarios are also investigated in the complex-wavy surface microchannel with constant surface temperature conditions by considering the Joule heating effect. The results show that the thermal entrance length significantly depends on the ratio of the electroosmotic flow velocity to the pressure-driven flow velocity. The longest entrance length is presented in the flow scenario of the favorable pressure gradient combined flow. In a thermally fully developed region, the heat transfer performance is dependent on the magnitude of the Joule heating and the geometry structure and is independent of flow scenarios. [Copyright &y& Elsevier]

Abstract: A numerical investigation is performed into the natural convection heat transfer characteristics within an enclosed cavity filled with nanofluid. The left and right walls of the cavity have a complex-wavy geometry and are maintained at a high and low temperature, respectively. Meanwhile, the upper and lower walls of the cavity are both flat and insulated. The nanofluid comprises Al2O3 nanoparticles suspended in pure water. In performing the analysis, the governing equations are formulated using the Boussinesq approximation and the complex-wavy-surface is modeled as the superimposition of two sinusoidal functions. The simulations examine the effects of the volume fraction of nanoparticles, the Rayleigh number and the complex-wavy-surface geometry parameters on the flow streamlines, isotherm distribution and Nusselt number within the cavity. The results show that for all values of the Rayleigh number, the Nusselt number increases as the volume fraction of nanoparticles increases. In addition, it is shown that the heat transfer performance can be optimized by tuning the wavy-surface geometry parameters in accordance with the Rayleigh number. Overall, the results presented in this study provide a useful insight into potential strategies for enhancing the convection heat transfer performance within enclosed cavities with complex-wavy-wall surfaces. [Copyright &y& Elsevier]

A numerical investigation is performed into the flow characteristics and mixing performance of electrokinetically driven non-Newtonian fluid in a contraction-expansion microchannel. In the study, the rheological behavior of the fluid is characterized using a power-law model. The results show that the volumetric flow rate reduces as the flow behavior index increases, and thus an improved mixing performance is obtained. Furthermore, it is shown that for all considered values of the flow behavior index, the mixing performance can be enhanced by increasing the ratio of the main channel width to the contraction channel width, extending the length of the contraction channel, assigning a smaller value to the nondimensional Debye-Hückel parameter, and applying an appropriate electric field strength. Finally, it is shown that although the mixing efficiency reduces with a reducing flow behavior index, an acceptable mixing performance can still be obtained given an appropriate specification of the flow conditions and geometry parameters. [ABSTRACT FROM AUTHOR]

This paper investigates the optimization of the performance of a solar powered Stirling engine based on finite-time thermodynamics. Heat transference in the heat exchangers between a concentrating solar collector and the Stirling engine is studied. The irreversibility of a Stirling engine is considered with the heat transfer following Newton's law. The power generated by a Stirling engine is used as an objective function for maximum power output design with the concentrating solar collector temperature and the engine thermal efficiency as the optimization parameters. The maximum output power of engine and its corresponding system parameters are determined using a genetic algorithm. [ABSTRACT FROM AUTHOR]

Abstract: An efficient method for the N,N′-di(Boc)-protected guanidines containing piperazine and homopiperazine scaffolds has been developed under multi-step microwave irradiation. Followed by alkylation of carbamate-protected guanidines with various alkyl halides is also explored. This protocol proceeds via deprotonation of the acidic N-carbamate hydrogen of the guanidine by sodium hydride on soluble polymer support. In this manner, highly functionalized guanidines were obtained after cleavage from the support. The reaction is tolerant of a wide range of functional groups on both the alkyl halide and guanidine components. In addition, the reaction is sufficiently simple workup by precipitation in each step to yield the substituted guanidines in high purity. In conjunction with microwave irradiation and soluble polymer support, this method provides an efficient route to access highly functionalized guanidines. [Copyright &y& Elsevier]

Because of the concern with the energy crisis, solar energy is considered one of the most promising alternatives to conventional energy sources, e.g. petroleum and coal, on account of its zero greenhouse gas emission. Accordingly, making solar cells operate at the maximum power point becomes a critical issue in such a field, for the reason that the cells provide a relatively low power output. Exhibiting non-linear I–V characteristics, solar cells are operated at varying operation points, resulting in an unstabilized output power. Aiming at the design of a sliding mode controller as well as the choice of a crucial gain kf made through fuzzy logic, this paper presents a maximum power tracking system as a way of reaching a maximum output power. The controller presented is then validated, through simulation and experiment, to provide a better response than a sliding mode controller in terms of the maximum power tracking performance. [ABSTRACT FROM PUBLISHER]

Abstract: A numerical investigation is performed into the mixing characteristics of electrokinetically-driven non-Newtonian fluids in microchannels containing patterned blocks. In performing the simulations, the rheological behavior of the fluid is described using a power-law model. Two different types of patterned blocks are considered, namely rectangular and wavy. The effects of the geometry parameters of the patterned blocks and the flow behavior index in the power-law model on the mixing efficiency within the microchannel are systematically explored. The results show that the rectangular patterned blocks yield a better mixing performance than the wavy patterned blocks. However, for both types of block, the mixing efficiency can be improved by increasing the width and length of the blocks and extending the total length of the block region. In addition, the results show that the flow behavior index in the power-low model has a significant effect on the mixing performance. Specifically, the volumetric flow rate increases with a decreasing flow behavior index, and therefore results in a poorer mixing performance. It is shown that a heterogeneous patterning of the zeta potential on the upper surfaces of the rectangular and wavy blocks prompts the formation of local flow recirculations, and therefore improves the mixing efficiency. In addition, it is shown that the mixing performance improves with an increasing magnitude of the heterogeneous surface zeta potential. Overall, the results show that the mixing efficiency of non-Newtonian fluids with a low flow behavior index can be improved by utilizing blocks with an appropriate geometry, applying a heterogeneous distribution of the surface zeta potential, and increasing the magnitude of the zeta potential. [Copyright &y& Elsevier]

Abstract: A novel method is proposed for enhancing the mixing performance in a crisscross micromixer by means of aperiodic time-varying electrokinetic perturbing flows. In the proposed approach, the aperiodic oscillating source used to modulate the perturbing electric potential is derived using the Sprott system. The effects of the perturbation conditions and micromixer geometry parameters on the fluid flow characteristics and mixing performance are analyzed by means of numerical simulations. The results show that irregularly-alternating flow recirculation structures are induced within the lateral channels of the micromixer, which cause a repeated stretching and folding of the species streams in the main channel and enhance the mixing performance as a result. It is shown that an effective improvement in the mixing performance can be obtained through a suitable specification of the scaling factor in the Sprott system. Furthermore, it is shown that the mixing performance can be further enhanced by assigning suitable values to the micromixer geometry parameters or by reducing the ratio of the main channel flow velocity to the lateral channel flow velocity. Overall, the numerical results show that an average mixing efficiency of more than 90% can be obtained by specifying the scaling factor in the Sprott system as 7.5, the ratio of the main channel velocity to the lateral channel velocity as 0.25, the separation distance between the lateral channels as equal to half the width of the main channel, and the width of the lateral channels as equal to the width of the main channel. [Copyright &y& Elsevier]

Abstract: A numerical investigation is performed into the flow characteristics of electrokinetically-driven non-Newtonian fluids in rough microchannels with a complex-wavy surface. In performing the simulations, the flow behavior of the non-Newtonian fluids is characterized using a power-law model and the complex-wavy surface is modeled via the superimposition of two sinusoidal functions. The simulations examine the respective effects of the flow behavior index, the non-dimensional Debye–Huckel parameter, and the complex wavy-surface geometry parameters on the flow field characteristics, volumetric flow rate and electric field intensity. The results show that the flow behavior of non-Newtonian fluids is significantly dependent on the value of the flow behavior index in the power-law model. Specifically, the volumetric flow rate increases as the flow behavior index reduces. For a pseudoplastic fluid, the volumetric flow rate increases with an increasing value of the non-dimensional Debye–Huckel parameter due to the corresponding reduction in viscosity. By contrast, for a dilatant fluid, the volumetric flow rate reduces as the Debye–Huckel parameter increases. Finally, it is shown that the velocity profile near the complex wavy surface is more sensitive to changes in the waveform geometry than that in the center of the channel. Overall, the results presented in this study provide a useful insight into the manipulation of non-Newtonian fluids within real-world microchannels characterized by surface roughness. [Copyright &y& Elsevier]

Abstract: In this study, the residual correction method is employed to predict the temperature distribution during laser heating process. The energy transfer induced by laser irradiation in the solid is described by Fourier’s law of conduction with an energy source modeled by Beer’s law. The approximate solution of temperature field is obtained by residual correction. Using the residual correction method, the precise average value of upper and lower approximate solutions is obtained and the error range between the analytical solution and the numerical solution can be analyzed. The results reveal that this method is an effective numerical method with satisfactory accuracy. [Copyright &y& Elsevier]

Abstract: A novel technique is proposed for enhancing the mixing performance of a ‘crisscross’ microfluidic mixer by means of aperiodically-varying perturbation flows. The effects of the perturbation and geometry parameters on the fluid flow characteristics and mixing performance are analyzed numerically. In performing the simulations, the flow field and species concentration field are obtained by solving the two-dimensional time-dependent Navier–Stokes equations and the convection–diffusion equation, respectively. In addition, the oscillating source used to modulate the perturbation flows is modeled using the Sprott system. The results show that the irregularly-alternating flow perturbations cause a repeated stretching and folding of the species streams and enhance the mixing performance as a result. It is shown that an effective improvement in the mixing performance can be obtained through a suitable choice of the Sprott system scaling factor. Moreover, it is shown that having assigned an appropriate scaling factor, the mixing performance can be further improved by specifying suitable values of the geometry and perturbation parameters. [Copyright &y& Elsevier]

This paper studies the velocity distributions and diffusing behaviors of the atoms in a nano-alloy cluster. A series of ternary alloy clusters, AuCuNi, and binary alloy clusters, CuNi are introduced in the molecular dynamics simulations. The velocity distributions of different types of atoms in both static and moving clusters are found to obey the Maxwell's velocity distribution with the individual mass of atoms and the inner temperature of clusters. Furthermore, the velocity distribution of whole atoms of the cluster is obtained by synthesizing the velocity distributions of compositions in the cluster according to the proportions. The consistency of the atomic motions in a moving cluster is discussed by inspecting the backward velocities of atoms, which are correlated to the translational velocity and the inner temperature of the cluster. The diffusing behaviors of the atoms in a cluster are also investigated from a viewpoint of the interatomic interactions, i.e. Cu atoms enhance the activities of Ni atoms, or Ni atoms reduce that of Cu atoms in the alloy clusters. [ABSTRACT FROM AUTHOR]

Abstract: A hybrid numerical technique which combines the differential transformation and finite difference method is utilized to investigate the annular fin with temperature-dependent thermal conductivity. The exposed surfaces of the fin dissipate heat to the surroundings by convection and radiation. The influences of the convective heat transfer coefficient, absorptivity, emissivity and thermal conductivity parameter on the temperature distribution are examined. The results show that the convective heat transfer plays a dominant role for heat dissipation under the convection–radiation condition. The optimum radii ratio of fin which maximizes the heat transfer rate and fin efficiency is also discussed. [Copyright &y& Elsevier]

Abstract: This paper proposes a new method for presenting sports videos. Tennis videos are used as an example for the implementation of a viewing program called as Tennis Video 2.0. For the methods in video analysis, background generation by considering the pixels in temporal and spatial distribution is proposed; foreground segmentation combining automatic trimap generation and matting model is proposed. To provide more functions in watching videos, the rendering flow of video contents and the semantic Scalability are proposed. With the new analysis and rendering tools, the presentation of sports videos has three properties—Structure, Interactivity, and Scalability. The experiments show that several broadcasting game videos are employed to evaluate the robustness and performance of the proposed system. For user study, 20 evaluators highly identify that Tennis Video 2.0 is a new presentation of sports videos and give people better viewing experience. [Copyright &y& Elsevier]

Laser trackers are widely used in industry for tasks such as the assembly of airplanes and automobiles, contour measurement, and robot calibration. However, laser trackers are expensive, and the corresponding solution procedure is very complex. The influence of measurement uncertainties is also significant. This study proposes a three-dimensional space position measurement system which consists of two tracking modules, a zero tracking angle return subsystem, and a target quadrant photodiode (QPD). The target QPD is placed on the object being tracked. The origin locking method is used to keep the rays on the origin of the target QPD. The position of the target QPD is determined using triangulation since the two laser rays are projected onto one QPD. Modulation and demodulation are utilized to separate the coupled positional values. The experiment results show that measurement errors in the X, Y, and Z directions are less than ±0.05% when the measured object was moved by 300, 300, and 200 mm in the X, Y, and Z axes, respectively. The theoretical measurement error estimated from the measurement model is between ±0.02% and ±0.07% within the defined measurable range. The proposed system can be applied to the measurements of machine tools and robot arms. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the RGB ratio is defined according to a reference color so that an image can be transformed from a conventional color space to the RGB ratio space. Different to traditional distance measurement, a road color model is determined by an ellipse area in the RGB ratio space enclosed by the estimated boundaries. The proposed dynamic fuzzy logic, where fuzzy membership functions are defined according to estimated boundaries, is introduced to implement clustering rules, such that each pixel will have its own fuzzy membership function corresponding to its intensity. A basic neural network is trained and used to achieve parameter optimization. Experimental results for road detection demonstrate the robustness of the proposed approach to variations in intensity. To provide obstacle information, especially for visually impaired people, Musical Instrument Digital Interface (MIDI) is introduced as the sound generator, and image-to-MIDI mapping algorithm is proposed. Experimental results show that the proposed method can adapt to various road types, and the resulting audio information successfully indicates the position and size of obstacles. [ABSTRACT FROM AUTHOR]

A hybrid numerical technique which combines the differential transformation and finite difference approximation is employed to predict the laser heating problem. The energy transfer induced by laser irradiation in the solid is described by Fourier's law of conduction with an energy source modeled by Beer's law. The influences of convective boundary and dimensionless energy absorption at the surface are examined. It is found that at low Biot number, the peak temperature occurs at the surface. As the biot number increases, the location of the peak temperature moves inwards. In addition, the differential transformation results in a concise procedure than other integral transform methods. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a new color space, called the RGB color ratio space, is proposed and defined according to a reference color such that an image can be transformed from a conventional color space to the RGB color ratio space. Because a color in the RGB color ratio space is represented as three color ratios and intensity, the chrominance can be completely reserved (three color ratios) and the luminance can be de-correlated with the chrominance. Different from traditional distance measurement, a road color model is determined by an ellipse area in the RGB ratio space enclosed by the estimated boundaries. A proposed adaptive fuzzy logic in which fuzzy membership functions are defined according to estimated boundaries is introduced to implement clustering rules. Therefore, each pixel will have its own fuzzy membership function corresponding to its intensity. A basic neural network is trained and used to achieve parameters optimization. The low computation cost of the proposed segmentation method shows the feasibility for real time application. Experimental results for road detection demonstrate the robustness to intensity variation of the proposed approach. [Copyright &y& Elsevier]

This paper presents a Z-tilts compensation stage with three piezoelectric actuators and three guided hinges, which are a combination of a two-dimensional rotational hinge and a spring-type hinge. In order to reduce the nonlinearity of the three piezoelectric actuators, the capacitor insertion method was applied on each piezoelectric actuator. The relationship between the improved nonlinearity and the decreased displacement with various inserted capacitors is discussed and suitable capacitors for the stage are determined. A three-dimensional feedback measuring system composed of a laser interferometer and a quadrant photodiode detector was used to directly measure the real working position of the platform of the Z-tilts compensation stage without measuring the individual displacement of the three piezoelectric actuators. The minimum displacement and angular displacement of the Z-tilt stage were ±10 nm and ±0.1 arc sec, respectively. The error of the dynamic response of z, θx, and θy with amplitudes of 3 μm of a sine wave at 30 Hz were ±70 nm, ±0.1 arc sec, and ±0.4 arc sec, respectively, with the capacitor insertion method and a simple proportional-integral controller. [ABSTRACT FROM AUTHOR]

A novel microfluidic mixing approach is brought up in this study--the streams of species are mixed by applying harmonic or chaotic electric fields to four electrodes in the mixing chamber. For analyzing the effects of the harmonic and chaotic electric fields on the fluid flow characteristics in the microfluidic mixer, as well as evaluating the corresponding mixing performance, several numerical simulations are performed in the pursuit of the two experimental goals mentioned. In the simulation, harmonic and chaotic oscillations in the electric field are modeled by the well-known Duffing equation. Simulation results show that periodic and aperiodic perturbation effects occur within the mixing chamber when harmonic and chaotic electric fields are applied to the electrodes, respectively. These periodic and aperiodic perturbations produce strong perturbation effects, which efficiently mix species. [ABSTRACT FROM AUTHOR]

This paper proposes a new ring-based triple-push voltage-controlled oscillator (VCO) architecture to achieve a wide tuning range and high operating frequencies. Two ring-based triple-push VCOs, one with a continuous frequency tuning range of 0.2-34 GHz, fabricated in 0.13-μm CMOS, and the other with a range of 0.1-65.8 GHz, fabricated in 90-nm CMOS, are presented in this paper. These two VCOs demonstrate that the proposed VCO architecture can achieve a very wide continuous tuning range, up to millimeter-wave frequencies, without any device-switching operations. In addition to the wide tuning range, the chip area of the proposed VCO is very small, allowing integration into a phase-locked loop. The power consumptions of the 0.2-34 and 0.1-658-GHz VCOs are 2-70 mW from a 2-V supply voltage, and 1.2-26.4 mW from a 1.2-V supply voltage, respectively. The fundamental and second harmonic rejections are better than 15 dB for both VCOs. [ABSTRACT FROM AUTHOR]

Abstract: Due to nonlinear I-V characteristics of photovoltaic cells, an maximum power point tracking algorithm is adopted to maximize the output power. In this paper, an approach for peak power tracking using the sliding mode control is proposed. The proposed controller is robust to environment changes and load variations. The stability and robustness of the controller are addressed. The performance of the controller is verified through simulations and experiments. It demonstrated that the proposed approach can be implemented effectively and economically. [Copyright &y& Elsevier]

Six novel conjugated copolymers (P1−P6) containing coplanar cyclopentadithiophene (CPDT) units (incorporated with bithiazole/thienyl-based monomers) were synthesized and developed for the applications of polymer solar cells (PSCs). Copolymers P1−P6covered broad absorption ranges from UV to near-infrared (400−800 nm) with narrow optical band gaps of 1.70−1.94 eV, which are compatible with the maximum solar photon reflux. Partially reversible p- and n-doping processes of P1−P6in electrochemical experiments were observed. Compared with those previously reported CPDT-based narrow band gap polymers, the proper molecular design for HOMO/LUMO levels of P1−P6induced relatively high photovoltaic open-circuit voltages in the PSC devices. Powder X-ray diffraction (XRD) analyses suggested that these copolymers formed highly self-assembled π−π stackings. Under 100 mW/cm2of AM 1.5 white-light illumination, bulk heterojunction PSC devices containing an active layer of electron donor copolymers P1−P6blended with electron acceptor [6,6]-phenyl C61butyric acid methyl ester (PCBM) in the weight ratio of 1:1 were explored, and the external quantum efficiency (EQE) measurements showed a maximal quantum efficiency of 60%. The PSC device containing P4in the weight ratio of 1:2 with PCBM gave the best preliminary result with an overall power conversion efficiency (PCE) of 3.04%, an open-circuit voltage of 0.70 V, a short-circuit current of 8.00 mA/cm2, and a fill factor of 53.7%. [ABSTRACT FROM AUTHOR]

We tried to image obstructive cholestasis by using a newly developed imaging system to measure the alterations of hepatobiliary function in living mice with their bile ducts ligated. A hepatic imaging window was installed on the upper abdomen soon after the mice underwent ligation of the common bile duct. On the next day, the mice received intravenous injection of rhodamine B isothiocyanate-dextran and carboxyfluorescein diacetate. The later would be transformed into fluorogenic carboxyfluorescein (detected at ∼500-550 nm) by hepatocytes and then excreted into bile canaliculi. The images were acquired by multiphoton microscopy. The fluorescence intensities at ∼500-550 nm within hepatocytes or sinusoids were measured in time series. In mice with bile duct ligation, bile canaliculi failed to appear during the whole observation period over 100 mm following carboxyfluorescein diacetate injection, whereas the fluorescence was retained much longer within sinusoids. Furthermore, the fluorescence intensities in sinusoids were persistently higher than in hepatocytes during the course. Bile duct ligation impedes hepatocytes to excrete carboxyfluorescein into bile canaliculi. The kinetics of fluorescence intensities in hepatocytes and sinusoids indicated there is an active machinery operating backflow of this fluorogenic bile solute from hepatocytes into sinusoids in the liver with obstructive cholestasis. [ABSTRACT FROM AUTHOR]

Nonvanishing determinants have emerged as an attractive criterion enabling a space-time code achieve the optimal diversity-multiplexing gains tradeoff. It seems that cyclic division algebras play the most crucial role in designing a space-time code with nonvanishing determinants. In this paper, we explicitly construct space-time codes for arbitrary numbers of transmit antennas that achieve nonvanishing determinants and the optimal diversity-multiplexing gains tradeoff over Z [i]. Unlike previous methods usually arising a field compositum for two or more fields, our scheme, which only requires one simple extension, constitutes a much more efficient and feasible advancement whether in theory or practice. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the coordinate transformation method is used to analyze the aerosol particle deposition from a stagnation flow onto an axisymmetric wavy disk under to the coupling effects of Brownian diffusion, convection, sedimentation, thermophoresis and electrophoresis. The transformed governing equations obtained by coordinate transformation are solved by the spline alternating-direction implicit method. Numerical results show that electrophoresis will increase the particle deposition effect. It reveals that the thermophoresis effect of the cold wall will induce a driving effort to force particles toward the wall and accelerate the deposition onto the wall. When Brownian diffusion and thermophoresis dominate the particle deposition process, the influence of the lumpy surface geometry will become stronger with the increase of the disk radius, and the mean particle deposition effect of the wavy disk would be less than that of the flat disk. [Copyright &y& Elsevier]

The geometry of a solid model can be determined in an effective manner if sufficient spatial information of its shape and corresponding edges can be obtained. The binocular vision system, in which images are obtained from calibrated cameras, has traditionally been the most popular method. In this paper, a virtual binocular vision system, which is composed of one CCD camera and a rotary platform, is proposed as an alternative for measuring three-dimensional objects. The fundamental matrix of the virtual binocular vision system is proposed such that the coordinates of feature points can be determined through an efficient searching and matching procedure. Subsequently, point clouds of the object can be obtained to construct a solid model by utilizing CAD software, such as CATIA and Pro-E. This model can in turn serve as a basis for further analysis and extended applications. [ABSTRACT FROM AUTHOR]