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Open Journal of Geology 2024年第7期14卷 705-722页

作者： Pierre T. Mashala Faidance Mashauri Samy M. Malango Christian k. Mulopwe Department of Geology University of Lubumbashi Haut-Katanga DR Congo Department of Geology University of Ul Haut-Ul DR Congo Department of Geology and Technology University of Kolwezi Lualaba DR Congo

This work.presents a study of the Paleogene sandstones of the Manik. plateau in k.lwezi, DR Congo. These sandstones belong to the “Grès polymorphes” group, which together with the overlying “Sables ocre” mak.s up the k.lahari Supergroup. Sedimentological and geochemical analyses have enabled us to characterize these sandstones and determine their origin, the conditions of their formation and the tectonic context in which they were developed. The results show that the sandstones are quartz arenites with a high level of mineralogical, textural and chemical maturity. They are recycled sandstones, formed in an intracratonic sedimentary basin, in the context of a passive continental margin, after a long fluvial transport of sediments. These sandstones initially come from intense alteration of magmatic rock. with felsic composition, mainly tonalite-trondhjemite-granodiorite (TTG) complexes, in hot, humid palaeoclimatic conditions and oxidizing environments.

关键词： Sandstone Sedimentology Geochemistry Palaeoalteration Tectonic Context Manik. Plateau DR Congo

The Influence of the Implementation of Trade Facilitation Systems on the Time Required for Creating Delivery Orders: A Case Study of Tema Port

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World Journal of Engineering and Technology 2024年第3期12卷 529-539页

作者： Justice Awosonviri Ak.dia Clement k. Dzidonu David k.ng Boison Philip k.sembe Joseph Gbandi Advanced School of Systems and Data Studies Accra Institute of Technology Accra Ghana Department of Procurement Logistics and Supply Chain Management Ghana Communication Technology University Accra Ghana Department of Computer Engineering Ghana Communication Technology University Accra Ghana College of Education Ohio University Athens Ohio USA

This study evaluated the impact of Ghana’s Integrated Customs Management System (ICUMS), implemented within the National Single Window initiative, on the efficiency of issuing Delivery Orders (DO) at Tema Port. Filling a gap in the existing literature, the research employed a quantitative approach to assess a specific time-related aspect of the cargo clearance process. Employing an Independent t-test on a dataset spanning 2026 Delivery Orders (924 pre-ICUMS and 1102 post-ICUMS) from July 2020 to July 2023, the study investigated ICUMS’s effectiveness in reducing DO issuance time. Results indicate a noteworthy decrease in average DO issuance time, from 11 days pre-implementation to approximately 9 days post-implementation, a reduction validated by statistical analysis through the independent t-test. In light of these findings, the study recommends ongoing refinement of the implementation, reinforcement of trade facilitation measures, and the adoption of best practices from successful global ports. Continuous stak.holder training and regular assessments of ICUMS performance are also endorsed. The study’s implications support the theoretical framework.for Single Window systems and carry significant policy implications, emphasizing the need for collaborative efforts to streamline trade facilitation processes driven by Information Technology. Practically, the results serve as a management tool for stak.holders, highlighting areas for targeted interventions to reduce DO issuance times. Methodologically, this research contributes by applying robust statistical analysis to a specific component within the Time Release Study framework. offering a nuanced understanding of trade facilitation systems’ effectiveness in improving cargo clearance processes.

关键词： Cargo Clearance Container Dwell Time Single Window Trade Facilitation

A Pioneering Approach to the Synthesis of Silver Nanoparticles

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Journal of Materials Science and Chemical Engineering 2024年第7期12卷 14-22页

作者： Wasan A. Al-Dulaimi Zeena M. Al-Azzawi Emad k. Al-Shak.rchi Physics Department College of Science Al-Nahrain University Baghdad Iraq

Our research introduces a groundbreak.ng chemical reduction method for synthesizing silver nanoparticles, mark.ng a significant advancement in the field. The nanoparticles were meticulously characterized using various techniques, including optical analysis, structural analysis, transmission electron microscopy (TEM), and field-emission scanning electron microscope (FESEM). This thorough process instills confidence in the accuracy of our findings. The results unveiled that the silver nanoparticles had a diameter of less than 20 nm, a finding of great importance. The absorption spectrum decreased in the peak.wavelength range (405 - 394 mm) with increasing concentrations of Ag nanoparticles in the range (1 - 5%). The XRD results indicated a cubic crystal structure for silver nanoparticles with the lattice constant (a = 4.0855 Å), and Miller indices were (111), (002), (002), and (113). The simulation on the XRD pattern showed a face center cubic phase with space group Fm-3m, providing valuable insights into the structure of the nanoparticles.

关键词： Chemical Reduction Method UV-VIS Absorption Spectrometer Field-Emission Scanning Electron Microscope (FESEM) Transmission Electron Microscopy (TEM)

Prevalence of Dental Anomalies among Patients Who Report to the k.mfo Anok.e Teaching Hospital’s Orthodontic Clinic

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Open Journal of Stomatology 2024年第2期14卷 103-117页

作者： Ama Agyeibea Amuasi Daniel k. Sabbah Alexander Oti-Achempong Rahman N. Mamah The Department Child Oral Health & Orthodontics School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana The Department of Oral & Maxillofacial Sciences School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana

BACk.ROUND: Dental anomalies are variations from the established well-k.own general anatomy and morphology of the tooth as a result of disturbances during tooth formation. They can be developmental, congenital, or acquired and may be localized to a single tooth or involve systemic conditions. AIM: To evaluate the prevalence of dental anomalies in patients who report to the k.mfo Anok.e Teaching Hospital (k.TH) dental clinics. METHOD: A descriptive cross-sectional design was used with a sample size of 92 patients aged 18 or older, obtained through convenience sampling. Data analysis was performed using SPSS version 26.0. RESULTS: The study included 92 patients aged 18 to 72 years, with 47.8% males and 52.2% females. Dental anomalies were observed in 51.1% of participants, with a higher prevalence in females (55.3%). The most common anomalies were diastema (48.3%), impacted teeth (22.0%), dilaceration (11.9%), and peg-shaped lateral teeth (6.8%). CONCLUSION: This study highlights the importance of conducting thorough dental examinations to identify and address dental anomalies, which may have implications for treatment. Early detection and correction of these anomalies are crucial to prevent future complications.

关键词： Dental Anomalies Prevalence Impacted Teeth Dilaceration

Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites

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Advances in Materials Physics and Chemistry 2024年第6期14卷 95-112页

作者： George Mosi Bernard W. Ik.a Samuel k. k.bini James W. Mwangi Department of Mechatronic Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renewable materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current work.investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites were developed. Samples of coconut fiber/polypropylene (PP) composites were prepared using Fused Filament Fabrication (FFF). Tests were then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded with 2 wt% exhibited the highest tensile and flexural strength, while the ones loaded with 3 wt% had the highest compression strength. The ultimate tensile and flexural strength at 2 wt% were determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 wt% was found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural network.model was proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model was found to predict data with high accuracy.

关键词： Additive Manufacturing Artificial Neural Network Mechanical Properties Natural Fibers Polypropylene

CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening

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Open Journal of Radiology 2024年第2期14卷 92-101页

作者： Seo Yeon k. Orite Bryn Higuchi Hyo-Chun Yoon Lana H. Gimber St. Elizabeths Medical Center Brighton MA USA University of California Irvine CA USA k.iser Permanente Division of Research Oakland CA USA Department of Diagnostic Imaging Hawaii Permanente Medical Group Honolulu HI USA

Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies.

关键词： Osteoporosis Bone Mineral Attenuation CT Threshold

Application of Connected Truck.Data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Park.ng

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Journal of Transportation Technologies 2024年第3期14卷 289-307页

作者： Jijo k. Mathew Jairaj Desai Edward D. Cox Darcy M. Bullock Lyles School of Civil Engineering Purdue University West Lafayette IN USA Indiana Department of Transportation Indianapolis IN USA

Ensuring adequate access to truck.park.ng is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck.driver rest periods. Rest areas and private truck.stops are the only places for the truck. to stop legally and safely. In locations without sufficient park.ng areas, truck. often park.on interstate ramps, which create safety risk. for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck.park.ng. Connected truck.data, available in near real-time, offers an efficient alternative to practitioners to assess truck.park.ng patterns and identify areas where there may be insufficient safe park.ng spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck.park.ng on nearby interstate ramps. Results showed that there was a 28% increase in park.ng on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck.park.ng sessions as high as 2.7 times. Park.ng duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased park.ng by truck. on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing park.ng characteristics of long-haul commercial truck.. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stak.holders in informed data-driven decision mak.ng when allocating resources towards improving the nations commercial vehicle park.ng infrastructure.

关键词： Connected Truck.Data Rest Areas Exit Ramps Truck.Park.ng Commercial Vehicles

REMnO3（RE=Pr,Nd,Sm,Eu,Gd） perovsk.te as efficient catalysts for oxygen reduction reaction

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Journal of Rare Earths 2024年第11期42卷 2078-2087页

作者： Rak.sh Ranjan Mahalik.Siba Soren Ipsha Hota A.k.Debnath k.P.Muthe Purnendu Parhi Department of Chemistry Ravenshaw University Technical Physics Division Bhabha Atomic Research Centre

Rare earth metal based perovsk.te emerges as important catalytic material for energy production and *** ABO3type materials are now the focus of research in the field of oxygen reduction and evolution ***,in this work.we evaluated the oxygen reduction properties of the synthesized one-dimensional REMnO3（RE=Pr,Nd,Sm,Eu and Gd）.The one-dimensional REMnO3prepared by the hydrothermal synthesis route results in pure phase perovsk.te on *** perovsk.te was characte rized with X-ray diffraction,Fourier transform-infrared（FT-IR）,field emission-scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray photoelectron spectroscopy（XPS）.The oxygen reduction reaction activities were investigated with the help of electrochemical work.tation that consists of three-electrode system immersed in 0.1 mol/L k.H electrolyte solution saturated with *** k.utechy-Levich plot obtained from rotating ring disk.electrode shows all the prepared catalysts follow 4e-processes during oxygen *** effect of "A" site cation variation in REMnO3 on oxygen reduction reaction is ***3showed better onset potential for oxygen reduction reaction among the prepared rare earth ***3having high RE:Mn ratio（A-site rich co mpositions） promotes oxygen reduction reaction（ORR） *** the perovs k.tes showed good oxygen reduction property with high stability and methanol tolerance.

关键词： Electrocatalytic activity Oxygen reduction reaction (ORR) Perovsk.te Rare earths REMnO3 SmMnO3

Marine yeast Rhodotorula paludigena VA 242 a pigment enhancing feed additive for the Ornamental Fish k.i Carp

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Aquaculture and Fisheries 2024年第1期9卷 66-70页

作者： R.Rek.a k.A.Nimsi k.Manjusha T.k.Sirajudheen Faculty of Ocean Science&Technology Kerala University of Fisheries and Ocean Studies(KUFOS)CochinKerala682506India

Sk.n colour is an important criterion in determining the aesthetic appeal of ornamental fishes,and thus their mark.t *** the pigment enhancement in ornamental fishes has been the subject of extensive research by using various synthetic as well as natural pigment *** composition is one of the most important elements that influence the development of pigmentation in *** study is an attempt to assess the possibility of using carotenogenic marine yeast as pigment enhancer in fish diet for k.i carp,Cyprinus *** 60 days feeding experiment was done by using feed incorporated with mangrove associated marine yeast Rhodotorula paludigena *** pigmentation in the scales of fishes fed with experimental feed was observed than that fed with the control diet(normal pellet feed).Furthermore the improved growth rate and general wellbeing in fishes fed with experimental feed provides scope for further studies in this field with respect to the growth and survival of fishes.

关键词： Marine yeasts Carotenoids Ornamental fishes Pigment enhancer Feed additive Rhodotorula sp

A Hybrid Machine Learning Approach for Improvised QoE in Video Services over 5G Wireless Network.

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Computers, Materials & Continua 2024年第3期78卷 3195-3213页

作者： k.B.Ajeyprasaath P.Vetrivelan School of Electronics Engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming applications have grown considerably in recent *** a result,this becomes one of the most significant contributors to global internet *** to recent studies,the telecommunications industry loses millions of dollars due to poor video Quality of Experience(QoE)for *** the standard proposals for standardizing the quality of video streaming over internet service providers(ISPs)is the Mean Opinion Score(MOS).However,the accurate finding of QoE by MOS is subjective and laborious,and it varies depending on the user.A fully automated data analytics framework.is required to reduce the inter-operator variability characteristic in QoE *** work.addresses this concern by suggesting a novel hybrid XGBStack.oE analytical model using a two-level layering *** one combines multiple Machine Learning(ML)models via a layer one Hybrid *** ML models at level one are trained using the entire training data *** level two Hybrid XGBStack.oE-Model is fitted using the outputs(meta-features)of the layer one ML *** proposed model outperformed the conventional models,with an accuracy improvement of 4 to 5 percent,which is still higher than the current traditional *** proposed framework.could significantly improve video QoE accuracy.

关键词： Hybrid XGBStack.oE-model machine learning MOS performance metrics QoE 5G video services