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VR-based digital twin for remote monitoring of mining equipment:Architecture and a case study

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 100-112页

作者： Jovana PLAVŠIĆ Ilija MIŠKOVIĆnorman BKeevil norman B.Keevil Institute of Mining Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada

Background Traditional methods for monitoring mining equipment rely primarily on visual inspections,which are time-consuming,inefficient,and *** article introduces a novel approach to monitoring mission-critical systems and services in the mining industry by integrating virtual reality(VR)and digital twin(DT)***-based DTs enable remote equipment monitoring,advanced analysis of machine health,enhanced visualization,and improved decision *** This article presents an architecture for VR-based DT development,including the developmental stages,activities,and stakeholders involved.A case study on the condition monitoring of a conveyor belt using real-time synthetic vibration sensor data was conducted using the proposed *** study demonstrated the application of the methodology in remote monitoring and identified the need for further development for implementation in active mining *** article also discusses interdisciplinarity,choice of tools,computational resources,time and cost,human involvement,user acceptance,frequency of inspection,multiuser environment,potential risks,and applications beyond the mining *** The findings of this study provide a foundation for future research in the domain of VR-based DTs for remote equipment monitoring and a novel application area for VR in mining.

关键词： Virtual reality Digital twin Condition monitoring Mining equipment

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： Olga Nabochenko Mykola Sysyn norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa Deutschland GmbH BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

Diet variability of snappers(Teleostei:Lutjanidae)in a bay-to-reef ecosystem of the Mexican Caribbean

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Water Biology and Security 2024年第1期3卷 53-59页

作者： Leon Felipe Martínez-Juarez Juan J.Schmitter-Soto Nancy Cabanillas-Teran norman Mercado-Silva El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Centro de Investigacion en Biodiversidad y Conservacion Universidad Autonoma del Estado de Morelos62209CuernavacaMorelosMexico

Fishes use environmental resources *** ontogenic movements among coastal habitats lead to diverse *** investigated the diets of seven snapper species(Lutjanus apodus,***,***,***,***,***,and Ocyurus chrysurus)in three interconnected coastal environments in the western Caribbean:Río Huach channel,Chetumal/Corozal bay,and the adjacent Xcalak reef *** three encompass all habitats used by the seven species in the study *** diets were mostly composed of fish and crustaceans,but dominance of either group varied among the studied habitats;for example,fish were the main prey for *** from the reef lagoon zone,but second in the *** are piscivorous-invertivorous mesopredators;the species that relied the most on fishes were *** and ***,whereas *** preferred *** content results revealed a high degree of dietary overlap among *** findings suggested a tradeoff in relative weight between fish and crustaceans as the main food source of snappers at these connected areas,supporting the hypothesis of niche *** results can be used as a baseline to further our understanding of the ecology and differences in resource use by snapper species in an area undergoing important anthropogenic changes.

关键词： Resource partitioning Chetumal/Corozal bay Quintana Roo Trophic ecology

Genetic and Agronomic Parameter Estimates of Growth, Yield and Related Traits of Maize (Zea mays L.) under Different Rates of Nitrogen Fertilization

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American Journal of Plant Sciences 2024年第4期15卷 274-291页

作者： Prince Emmanuel norman Lansana Kamara Aloysius Beah Kelvin Sahr Gborie Francess Sia Saquee Sheku Alfred Kanu Fayia Augustine Kassoh Yvonne Sylvia Gloria Ethel norman Abdul Salaam Kargbo Sierra Leone Agricultural Research Institute (SLARI) Freetown Sierra Leone School of Agriculture Njala University Njala Campus Njala Sierra Leone School of Natural Resources Management Njala University Njala Campus Njala Sierra Leone Department of Agro Biotechnology Institute of Agriculture RUDN University Moscow Russia Faculty of Development Agriculture & Natural Resources Management Eastern Technical University of Sierra Leone Kenema Sierra Leone

This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha−1) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p −1 plots exhibiting the lowest and highest grain yields of 1238 kg∙ha−1 and 2098 kg∙ha−1, respectively. Variety and nitrogen effects on partial factor productivity (PFPN), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p N (41.3 kg grain kg−1∙N) and AEN (29.4 kg grain kg−1∙N) were obtained in the 30 kg∙N∙ha−1 plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL−1 spent on N) were obtained in the 180 kg∙N∙ha−1. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fe

关键词： Nitrogen Rates Genetic and Agronomic Estimates Introduced Genotypes Grain Yield Zea mays

Variation in Yellow Root Cassava (Manihot esculentus Crantz) Genotypes and Phenotypic Relationship for Selected Postharvest and Morphological Traits

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Agricultural Sciences 2024年第9期15卷 993-1008页

作者： Suffian Mansaray Prince Emmanuel norman Joseph Sherman-Kamara Isata Kamanda Kadiatu Nannah Serry Post-Harvest and Nutrition Sierra Leone Agricultural Research Institute (SLARI) Tower Hill Freetown Sierra Leone Department of Agriculture Engineering School of Technology Njala University Njala Campus Bo Sierra Leone Germplasm Enhancement and Seeds System Sierra Leone Agricultural Research Institute (SLARI) Tower Hill Freetown Sierra Leone

This study evaluated the variation in yellow root cassava (Manihot esculentus Crantz) genotypes and phenotypic relationship for selected postharvest and morphological traits. The trial was established at the Njala Agricultural Research Centre experimental site, Njala, during 2017/2018 cropping season in a randomized complete block design with three replications. Findings showed that the higher the total carotene content (TCC) in yellow flesh cassava genotypes, the longer the rate of postharvest physiological deterioration (PPD). Genotypes TR-0051-TCC/17 and TR-0012-TCC/17 recorded higher TCC (18.9 µg/g and 13.6 µg/g) and longer rate of PPD (4.29 and 3.14), respectively. Genotypes TR-0051-TCC/17, TR-0016-TCC/17, TR-0028-TCC/17, TR-0012-TCC/17 and TR-0020-TCC/17 had the highest TCC values of 18.9 µg/g, 16.09 µg/g, 14.72 µg/g, 13.6 µg/g and 11.23 µg/g with corresponding higher color chart values of 6, 6, 6, 5, and 6, respectively. This suggests the direct dependence of TCC on the root parenchyma color intensity in yellow flesh cassava genotypes. Findings also show a direct relationship between morphological and postharvest traits in yellow flesh cassava genotypes that could be exploited for the genetic improvement of cassava for increased shelf life, nutrition and related quality traits, as well as conservation and utilization of the crop.

关键词： Cassava Variability Regression Correlation Postharvest and Morphological Traits

Projected Changes in Extreme Event Indices for Alaska

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Atmospheric and Climate Sciences 2024年第2期14卷 191-209页

作者： John E. Walsh Kyle Redilla norman Shippee Lukas Cheung David Bigelow Ronni Wilcock International Arctic Research Center University of Alaska Fairbanks Fairbanks USA Stantec Ottawa Canada Stantec Montreal Canada Stantec Calgary Canada Two Bears Environmental Consulting Anchorage USA

As climate has warmed in recent decades, Alaska has experienced a variety of high-impact extreme events that include heat waves, wildfires, coastal storms and freezing rain. Because the warming is projected to continue, it is essential to consider future changes when planning adaptation actions and building resilience. In this study, we synthesize information on future changes in extreme events in Alaska from an ensemble of regional climate model simulations performed as part of Arctic-CORDEX (Coordinated Regional Climate Downscaling Experiment). A set of 13 extreme event indices, based on those developed by the World Climate Research Programme’s Expert Team on Climate Change Detection and Indices (ETCCDI), are evaluated from the Arctic-CORDEX output for Alaska. Of the 13 indices, six pertain to temperature, five to total precipitation, one to wind and one to snow. The results for locations in seven different climate zones of Alaska include large increases (5˚C - 10˚C) in the temperature thresholds for the five hottest and coldest days of the year, and large increases in warm spell duration and decreases in cold spell duration. Changes in the cold day temperature threshold are generally larger than the changes in the hot day temperature threshold, consistent with the projections of a stronger warming in winter than in summer in Alaska yearly maximum 1-day and 5-day precipitation amounts as well as the yearly number of consecutive wet days are projected to increase at all locations. The indices for heavy snow days and high-wind days show mixed changes, although the results indicate increases in heavy snow days at the more northern locations and increases in windy days at coastal locations. The changes in the extreme event indices continue through 2100 under the higher-emission (RCP 8.5) emission scenario, while the changes generally stabilize under the lower-emission (RCP 4.5) scenario. .

关键词： Extreme Events Temperature Precipitation Alaska Climate

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真菌和花卉保护并赞颂大自然

空中英语教室（高级版．彭蒙惠英语） 2024年第8期 20-22,43-45页

作者： Mary Ann Thomas norman Winter 不详

每个人都可以是博物学家查尔斯·毕尔是那种会把蛇放进口袋里的孩子。郊区可能会很无聊。草坪和道路无法为好奇的男孩提供多样的生物。不过,不久之前退休的宾夕法尼亚州西部自然资源保护协会保护科学资深主任毕尔却找到了在野外消磨时... 详细信息

每个人都可以是博物学家查尔斯·毕尔是那种会把蛇放进口袋里的孩子。郊区可能会很无聊。草坪和道路无法为好奇的男孩提供多样的生物。不过,不久之前退休的宾夕法尼亚州西部自然资源保护协会保护科学资深主任毕尔却找到了在野外消磨时间的方式。

关键词：自然资源保护宾夕法尼亚州博物学家大自然

Oviposition Site Preference and Its Effects on Subsequent Development of Variegated Grasshopper (Zonocerus variegatus L.) under Laboratory Conditions

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Advances in Entomology 2024年第3期12卷 143-154页

作者： Saffea Joseph Torto Abu James Sundufu Alusaine Edward Samura Sahr Ngoba Fomba Dennis Peter Musa Skeku Alfred Kanu Prince Emmanuel norman Department of Crop Protection School of Agriculture and Food Sciences Njala Sierra Leone Department of Horticulture School of Natural Resources Management Njala University Njala Sierra Leone Department of Crop Science School of Agriculture and Food Sciences Njala University Njala Sierra Leone Germplasm Enhancement and Seeds Systems Sierra Leone Agricultural Research Institute Freetown Sierra Leone

Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.

关键词： Development Oviposition Oviposition Site Preference Soil Types Variegated Grasshopper

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将乐高唐话词汇

语言与文化论丛

语言与文化论丛 2024年第02期 3-82页

作者： Jerry norman 秋谷裕幸沈瑞清爱媛大学新加坡国立大学

【编者按语】2012年6月,罗杰瑞先生在临终前将他整理输入的将乐高唐话的词汇表发给了沈瑞清,这是他在晚年呼吸越来越困难的情况下却仍然坚持完成的一件“私活”。(1)2023年2月,秋谷裕幸访问新加坡国立大学期间开始本文的整理工作,沈瑞...

【编者按语】2012年6月,罗杰瑞先生在临终前将他整理输入的将乐高唐话的词汇表发给了沈瑞清,这是他在晚年呼吸越来越困难的情况下却仍然坚持完成的一件“私活”。(1)2023年2月,秋谷裕幸访问新加坡国立大学期间开始本文的整理工作,沈瑞清则做了补充与校对。我们要特别感谢罗杰瑞夫人陈恩绮女士授权我们整理发表这篇罗杰瑞先生的遗作,来表达我们对罗先生深深的怀念。

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