Indium phosphide (InP) quantum dots (QDs) have demonstrated great potential for light-emitting diode (LED) application because of their excellent optical properties and nontoxicity. However, the over performance of InP QDs still lags behind that of CdSe QDs, and one of main reasons is that the Zn traps in InP lattices can be formed through the cation exchange in the ZnSe shell growth process. Herein, we realized highly luminescent InP/ZnSe/ZnS QDs by constructing Se-rich shielding layers on the surfaces of InP cores, which simultaneously protect the InP cores from the invasion of Zn2+ into InP lattices and facilitate the ZnSe shell growth via the reaction between Zn2+ precursors and Se2– shielding layers. The as-synthesized green InP/ZnSe/ZnS QDs had a high photoluminescence quantum yield (PLQY) of up to 87%. The fabricated QLEDs present a peak external quantum efficiency of 6.2% with an improved efficiency roll-off at high luminance, which is 2 times higher than that of control devices.

With the various applications of the Internet of Things, research into wireless sensor networks (WSNs) has become increasingly important. However, because of their limited energy, the communication abilities of the wireless nodes distributed in the WSN are limited. The main task of WSNs is to collect more data from targets in an energy-efficient way, because the battery replacement of large amounts of nodes is a labor-consuming work. Although the life of WSNs can be prolonged through energy-harvesting (EH) technology, it is necessary to design an energy-efficient routing protocol for the energy harvesting-based wireless sensor networks (EH-WSNs) as the nodes would be unavailable in the energy harvesting phase. A certain number of unavailable nodes would cause a coverage hole, thereby affecting the WSN’s monitoring function of the target environment. In this paper, an adaptive hierarchical-clustering-based routing protocol for EH-WSNs (HCEH-UC) is proposed to achieve uninterrupted coverage of the target region through the distributed adjustment of the data transmission. Firstly, a hierarchical-clustering-based routing protocol is proposed to balance the energy consumption of nodes. Then, a distributed alternation of working modes is proposed to adaptively control the number of nodes in the energy-harvesting mode, which could lead to uninterrupted target coverage. The simulation experimental results verify that the proposed HCEH-UC protocol can prolong the maximal lifetime coverage of WSNs compared with the conventional routing protocol and achieve uninterrupted target coverage using energy-harvesting technology.

With the continuous innovation of network technology, various kinds of convenient network technologies have grown, and human dependence on network technology has gradually increased, which has resulted in the importance of network information security issues. With the continuous development of my country’s industrialization, the application of sensors is becoming more and more extensive, for example, the security vulnerabilities and defects in the operating system itself. Traditional sensors can “perceive” a certain thing or signal, convert it into an electrical signal and record it, and then use a conversion circuit to output the electrical signal into a value or other display form that is conducive to observation. Nowadays, sensors have been further developed. Based on the original “perception” function, combined with computer technology, it integrates data storage, data processing, data communication, and other functions, so that it has analysis functions and can better display information. The technical level has reached a new level. Early intelligent recognition mainly used the uniqueness of finger and palm lines to scan and contrast, but due to some weather reasons or skin texture constraints caused by skin texture, these methods showed certain limitations. This paper proposes a new computer vision-based algorithm from face detection technology and face recognition technology. In the face detection technology, it is mainly introduced from the OpenCV method. Face recognition technology is improved in practical applications through the Seetaface method and YouTu method. At the same time, using the contrast experiment, the detection and recognition rates under the three different requirements of side face detection, occlusion detection, and facial exaggerated expression are compared, and the accuracy of each method is improved. The results show that each case is compared in each case. The advantages and disadvantages of the algorithm effectively verify the effectiveness of the method.

HighlightsEffectively separating the “white pollution” from agricultural soil.Three different spades for mechanical recycling residual film were tested.All spades had a similar draft requirement and soil disturbance trend.Spade A provided a higher residual film recovery rate.Abstract. Plastic film mulching cultivation provides important support for increasing the crop yield and ensuring food security, but residual plastic film pollution has become a prominent problem affecting the sustainable development of agriculture especially in northwest China. Recovery of thicker film by residual plastic film recycling machines may represent an effective way to solve this problem. In this study, a combined implement comprising three different spades (spades A, B, and C) were tested in a cotton field to compare their performance. All three types of spades were tested at a travel speed of 4.5 kmh-1 and a working depth of 40 mm. The residual plastic film recovery rate, soil draft force, soil disturbance characteristics (furrow profile), and cotton stubble uprooting were measured. Spade B had a higher draft force than the other spades. This trend was also observed for the soil disturbance area. Spades A and C produced stubble uprooting of approximately 5%, and spade B resulted in an approximately 5.7% larger degree of uprooting. Spade A had the largest recovery rate of residual film, while spade C had the smallest one. Overall, considering both recovery rate of residual film and draft force requirement, spade A showed better performance compared to spades B and C. Keywords: Draft force, Residual plastic film, Recovery rate, Soil disturbance, Spade.

No abstract