Design and Collaborative Operation of Multimobile Inspection Robots in Smart Microgrids

This paper investigates the substation inspection problems of multimobile robots for large power stations in smart microgrids. Most multirobot inspection robots generally face the challenge of path planning, while the current widely used biological excitation neural network (BENN) methods often have the defect of the neuronal active field near boundaries and obstacles. To end this, we propose an improved biological excitation neural network (IBENN) method for path planning based on a detailed architecture and ontology framework, through which the single-point inspection, multipoint inspection, and full-area inspection tasks of substations in smart microgrids can be well completed. Simulation results show that the designed IBENN-based multirobot collaboration inspection (MRCI) system can effectively shorten the path as well as the number of turns and then show better performance than most existing results when implementing various substation inspection tasks.

Exploring weft knit fabric defects based on their presence and quality impact: A case study

While addressing grey fabric quality in a renowned circular weft knitting mill of Bangladesh, the authors experienced some questionable approach practiced by knitters. The subjective nature of defect detection by knitters/inspectors often time causes wrong emphasizing on frequently occurring defect(s) instead of focusing on influential defect(s) and subsequently, employing wrong quality control approach to minimize the grey fabric defects. Knit fabric defects (e.g., hole, stain, press-off, gout, miss knit, barrè, tucking, etc.) should be assessed by type, fault coverage, gravity and the frequency of occurrence instead of focusing only on frequency of occurrence in the fabric. In this study, grey weft-knitted fabric quality is investigated based on influential defects instead of frequently occurring defects. Quality data of single jersey, fleece and 1X1 rib were gathered and analyzed from an established knitting factory in Bangladesh over three months duration. A fabric inspection machine and 4-point inspection method were employed in this study. Gout was found as the most frequently occurring defect for each fabric type but not influential for rib fabric. For a significant amount of knitted fabrics, totaling of 55,524.91 m2 inspected fabric, the most occurring defects were ranked as gout, press-off, hole, miss knit, stain, and tucking and influential defects (based on inspection points) were ranked as gout, press-off, hole, stain, miss knit, and tucking (highest to lowest). In the inspection report, the knitter/inspector mistakenly categorized gout as the most occurring as well as the most influential defect for 1X1 rib fabrics and suggested remedies accordingly.

Rail Base Point Inspection Using the Mirror through Transmission Testing Technique on Multiple Reflections

Рассмотрена возможность контроля пера подошвы железнодорожного рельса Р65 для обнаружения дефектов типа 69.2. Целью данного исследования является обоснование возможности использования многократного зеркально-теневого метода для контроля пера подошвы рельса и выбора его параметров. Для этого был рассчитан акустический тракт распространения поперечных волн в рельсе с дефектами подошвы и без дефектов при различных углах ввода. Рассчитанный акустический тракт показал, что оптимальным углом ввода при установке преобразователя на шейку рельса является угол 58º, так как при данном угле ввода поперечная волна распространяется до самого края пера подошвы рельса, при этом наблюдается минимальное количество неинформативных переотражений от геометрического профиля рельса. В акустическом тракте прохождения ультразвуковой волны при наличии дефекта с диаметром 3,5 мм и глубиной 7 мм наблюдается наибольшее количество переотражений ультразвуковой волны. При увеличении размеров дефекта характер переотражений меняется – волна больше расходится, время прихода отраженного сигнала увеличивается по сравнению с лучом в бездефектном участке рельса.Для подтверждения возможности выявления дефектов в подошве рельса типа Р65 было проведено экспериментальное исследование многократным зеркально-теневым методом с использованием поперечных волн. В качестве измерительных средств использовался ультразвуковой дефектоскоп УД2-70 «Луч», для возбуждения и приема ультразвуковых волн использовался пьезоэлектрический преобразователь с переменным углом ввода. Результатами эксперимента подтверждено, что оптимальным углом ввода для обнаружения дефектов в подошве рельса является угол 58º. При выбранных параметрах наблюдается минимум неинформативных переотражений, и амплитуда многократно отраженного сигнала на бездефектном участке выше. Наличие дефекта приводит к снижению амплитуды сигнала более чем в 2 раза.

Evaluating the Efficacy of the Systems Approach at Mitigating Five Common Pests in Oregon Nurseries

In Oregon, the U.S. Nursery Certification (USNCP), Grower Assisted Inspection (GAIP), and Shipping Point Inspection (SPI) programs are used to certify nursery plants as pest free. To compare the programs' effectiveness for mitigating pest risk, potted plants grown within two USNCP, two GAIP, and two SPI nurseries were surveyed for Phytophthora root rot (Phytophthora spp.), Phytophthora foliar blight (Phytophthora spp.), bittercress (Cardamine spp.), snails and slugs (Class Gastropoda), and root weevils (Otiorhynchus spp.). A total of 1,635 plots were surveyed in the nurseries, with one or more pests detected in 1,003 plots. Based on the total percentage of plots found infested with a pest, significantly fewer were detected in the GAIP nurseries (55%) than in the USNCP nurseries (68%). However, bittercress incidence was significantly higher in GAIP nurseries (21%), while snails and slugs incidence was significantly higher in USNCP nurseries (49%), and Phytophthora root rot incidence was significantly higher in SPI nurseries (31%). Also, the plant families grown by the nurseries had a significant impact on pest incidence for two of the target pests, Phytophthora root rot and root weevils. While the GAIP seemed the best at mitigating pest incidence overall, none of the certification programs was consistently the most effective against all five target pests.

Application of Information Point Inspection System in the Modern Coal Preparation Plant

Device detection and diagnosis technology is one of the key technologies to guarantee safe, reliable and economical production, to achieve scientific management and to maximize efficiency of the equipment. Off-line diagnosis, which is also called point inspection, has been applied in most modern large-scale enterprises. According to the running state of the point inspection management system of Coal Washing and Processing in Shendong Mine Group Co…LTD, this paper mainly gives a brief introduction to information point inspection management system in modern coal preparation plant in terms of the architecture, implementation, characteristics and workflow of it, and offer the experience for other enterprises of our country to draw on.