PFYOLOv4: An Improved Small Object Pedestrian Detection Algorithm

With the development of deep convolutional neural networks, the effect of pedestrian detection has been rapidly improved. However, there are still many problems in small target pedestrian detection, for example noise (such as light) interference, target occlusion, and low detection accuracy. In order to solve the above problems, based on YOLOv4 algorithm, this paper proposes an improved small target pedestrian detection algorithm named PF_YOLOv4. The algorithm is improved in three aspects on the basis of the YOLOv4 algorithm: firstly, a soft thresholding module is added to the residual structure of the backbone network to perform noise reduction process on interference factors, such as light to enhance the robustness of the algorithm; secondly, the depthwise separable convolution replaces the traditional convolution in the YOLOv4 residual structure, to reduce the number of network model parameters; finally, the Convolutional Block Attention Module (CBAM) is added after the output feature map of the backbone network to enhance of the network feature expression. Experimental results show that the PF_YOLOv4 algorithm outperforms most of the state-of-the-art algorithms in detecting small target pedestrians. The mean Average Precision (mAP) of the PF_YOLOv4 algorithm is 2.35% higher than that of the YOLOv4 algorithm and 9.67% higher than that of the YOLOv3 algorithm, while the detection speed is slightly higher than that of YOLOv4 algorithm

Industrial robot selection using a multiple criteria group decision making method with individual preferences.

This paper proposes a multiple criteria group decision making with individual preferences (MCGDM-IP) to address the robot selection problem (RSP). Four objective criteria elicitation approaches, namely, Shannon entropy approach, CRITIC approach, distance-based approach, and ideal-point approach, are proposed to indicate individual decision makers. A preliminary group decision matrix is therefore formulated. Both preferential differences representing the preference degrees among different robots, and preferential priorities representing the favorite ranking of robots for each individual decision maker, are analyzed to propose a revised group decision matrix. A satisfaction index is developed to manifest the merits of the proposed MCGDM-IP. An illustrative example using the data drawn from previous literature is conducted to indicate the effectiveness and validity of MCGDM-IP. The results demonstrate that the MCGDM-IP could generate a more satisfactory scheme to evaluate and select industrial robots, with an improvement of group satisfactory level as 2.12%

Resistive Switching of Plasma–Treated Zinc Oxide Nanowires for Resistive Random Access Memory

ZnO nanowires (NWs) were grown on Si(100) substrates at 975 °C by a vapor-liquid-solid method with ~2 nm and ~4 nm gold thin films as catalysts, followed by an argon plasma treatment for the as-grown ZnO NWs. A single ZnO NW–based memory cell with a Ti/ZnO/Ti structure was then fabricated to investigate the effects of plasma treatment on the resistive switching. The plasma treatment improves the homogeneity and reproducibility of the resistive switching of the ZnO NWs, and it also reduces the switching (set and reset) voltages with less fluctuations, which would be associated with the increased density of oxygen vacancies to facilitate the resistive switching as well as to average out the stochastic movement of individual oxygen vacancies. Additionally, a single ZnO NW–based memory cell with self-rectification could also be obtained, if the inhomogeneous plasma treatment is applied to the two Ti/ZnO contacts. The plasma-induced oxygen vacancy disabling the rectification capability at one of the Ti/ZnO contacts is believed to be responsible for the self-rectification in the memory cell

Clinical evidence on the efficacy and safety of an antioxidant optimized 1.5% salicylic acid (SA) cream in the treatment of facial acne: an open, baseline-controlled clinical study

BACKGROUND/PURPOSE: Acne pathogenesis is multifactorial and includes inflammation. Combining active ingredients targeting multiple components of acne pathogenesis may yield optimal outcomes. This study investigates the safety and efficacy of an antioxidant optimized topical salicylic acid (SA) 1.5% cream containing natural skin penetration enhancers in combination with antioxidant activity for treatment of facial acne. METHODS: A total of 20 patients with facial acne, aged 19-32 years (2 males, 18 females; mean age 26.1 +/- 3.2), were enrolled. Patients were treated with topical 1.5% SA cream and instructed to apply the cream as a thin film over the affected area twice daily (in the morning and evening) for 4 weeks. Inflammatory severity, numbers of papules and pustules were evaluated by investigators at day 0 and weekly, and patients ranked their improvement. RESULTS: In all, 95% of patients improved: 20% had complete clearing, 30% had significantly improved, 15% had moderate improvement, 30% had mild improved, and there was no response in 5% of the patients by 4 weeks of treatment. No side effects were observed. CONCLUSION: This study demonstrates the efficacy and safety of this optimized topical 1.5% SA cream containing natural skin penetration enhancers in combination with antioxidant activity when applied twice daily for the reduction of facial acne; in particular, it is most effective for mild-to-moderate acne

Tuning of Rashba/Dresselhaus Spin Splittings by Inserting Ultra-Thin InAs Layers at Interfaces in Insulating GaAs/AlGaAs Quantum Wells

The ratio of Rashba and Dresselhaus spin splittings of the (001)-grown GaAs/AlGaAs quantum wells (QWs), investigated by the spin photocurrent spectra induced by circular photogalvanic effect (CPGE) at inter-band excitation, has been effectively tuned by changing the well width of QWs and by inserting a one-monolayer-thick InAs layer at interfaces of GaAs/AlGaAs QWs. Reflectance difference spectroscopy (RDS) is also employed to study the interface asymmetry of the QWs, whose results are in good agreement with that obtained by CPGE measurements. It is demonstrated that the inserted ultra-thin InAs layers will not only introduce structure inversion asymmetry (SIA), but also result in additional interface inversion asymmetry (IIA), whose effect is much stronger in QWs with smaller well width. It is also found that the inserted InAs layer brings in larger SIA than IIA. The origins of the additional SIA and IIA introduced by the inserted ultra-thin InAs layer have been discussed

Sunburn protection as a function of sunscreen application thickness differs between high and low SPFs

Background Sunscreens are an important component of healthy sun-protection behavior. To achieve satisfactory protection, sunscreens must be applied consistently, evenly and correctly. Consumers do not apply sunscreen properly and, therefore, do not achieve the protection indicated by the label 'sun protection factor' (SPF). The objective of the present study was to determine the actual sun(burn) protection given by a range of sunscreen application thickness levels for both low and high SPF formulas. Subjects and Methods Forty study subjects were recruited from each of three geographical regions in China. Sunscreens with label SPFs of 4, 15, 30, and 55 were tested at application levels of 0.5, 1.0, 1.5, and 2.0 mg/cm2 in three laboratories using a standard SPF protocol. Results Sunscreens with lower SPFs (4 and 15) showed a linear dose-response relationship with application level, but higher SPF (30 and 55) product protection was exponentially related to application thickness. Conclusion Sunscreen protection is not related in one uniform way to the amount of product applied to human skin. Consumers may achieve an even lower than expected sunburn protection from high SPF products than from low SPF sunscreens

Observation of Extrinsic Photo-Induced Inverse Spin Hall Effect in a GaAs/AlGaAs Two-Dimensional Electron Gas

Abstract The inverse spin Hall effect induced by circularly polarized light has been observed in a GaAs/AlGaAs two-dimensional electron gas. The spin transverse force has been determined by fitting the photo-induced inverse spin Hall effect (PISHE) current to a theoretical model. The PISHE current is also measured at different light power and different light spot profiles, and all the measurement results are in good agreement with the theoretical calculations. We also measure the PISHE current at different temperatures (i.e., from 77 to 300 K). The temperature dependence of the PISHE current indicates that the extrinsic mechanism plays a dominant role, which is further confirmed by the weak dependence of the PISHE current on the crystal orientation of the sample