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effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah C.Keles W.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

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Modelling the brittle rock failure by the quaternion-based bonded-particle model in DeM

Rock Mechanics Bulletin

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Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao Philip e.f.Collins Department of Civil and environmental engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DeM).Unlike traditional approaches that utilize euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplifies the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(UCS)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** UCS was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DeM bonded model Uniaxial compression test Rate dependent Internal damage

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Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.eggleton Cody J.Salzmann Joseph e.Kaiser Shannon C.f.Smith Department of Aquaculture and fisheries University of Arkansas at Pine Bluff Arkansas Game and fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P e post-carp period as reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species fish assemblage Oxbow lake Large river

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乳腺数字化体层融合成像全自动定量估测乳腺体积密度:数字化钼靶成像和MR成像比较的初步研究结果

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国际医学放射学杂志 2016年第3期 310-310页

作者： S.Pertuz e.S.McDonald S.P.Weinstein e.f.conant D.Kontos 孔祥 Department of Radiology Perelman School of MedicineUniversity of Pennsylvania

摘要目的评估乳腺数字化体层融合技术(DBT)中乳腺体积密度(VBD)全自动化定量方法,并比较全数字化乳腺钼靶成像(ffDM)和MR成像的结果。方法本研究经伦理委员会批准并符合HIPAA要求,回顾性收集了2011年10月—2012年9月进行乳腺癌筛查的68... 详细信息

摘要目的评估乳腺数字化体层融合技术(DBT)中乳腺体积密度(VBD)全自动化定量方法,并比较全数字化乳腺钼靶成像(ffDM)和MR成像的结果。方法本研究经伦理委员会批准并符合HIPAA要求,回顾性收集了2011年10月—2012年9月进行乳腺癌筛查的68例女性的双侧乳腺DBT影像、ffDM影像以及矢状面乳腺MR影像。DBT成像中VBD作为一种全自动化的计算机算法被开发用于定量评

关键词：乳腺 DBT VBD 乳房 ffDM MR 体层体积密度

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A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa f.Soliman fatma e.fadl-Allah Walid el-Shafai Mahmoud I.Aly Maali Alabdulhafith fathi e.Abd el-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of electronics and electrical Communications engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier frequency Division Multiple Access(SC-fDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-fDMA systemas an adopted communication *** introduces a robust image communication framework over SC-fDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-fDMA *** linearMinimumMean Square error(MMSe)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-fDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

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数字化乳腺X线摄影中采集剂量对乳腺密度定量评估的影响:ACRIN PA 4006结果

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国际医学放射学杂志 2016年第6期 675-675页

作者： L.Chen S.Ray B.M.Keller S.Pertuz e.S.McDonald e.f.conant 汪洋 Department of Radiology Perelman School of Medicine at the University of Pennsylvania

摘要目的探索数字化乳腺X线摄影中采集剂量对乳腺密度评估的影响。方法回顾性分析美国放射学会宾夕法尼亚成像网络4006号实验对女性乳腺的群体研究,该研究

关键词：乳腺密度 ACRIN PA 4006 剂量用药量定量评估摄影美术

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enhancing early Detection of Lung Cancer through Advanced Image Processing Techniques and Deep Learning Architectures for CT Scans

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Computers, Materials and Continua 2024年第1期81卷 271-307页

作者： Tawfik N. emara H.M. el-Shafai W. Soliman N.f. Algarni A.D. Abd el-Samie f.e. Computers and Systems Department Electronics Research Institute El Nozha Huckstep Cairo 12622 Egypt Department of electronics and electrical Communications engineering Faculty of Electronic Engineering Menoufia University Menouf 32952 Egypt Security engineering Lab Computer Science Department Prince Sultan University Riyadh 11586 Saudi Arabia Department of Information Technology College of Computer and Information Sciences Princess Nourah bint Abdulrahman University Riyadh 84428 Saudi Arabia

Lung cancer remains a major concern in modern oncology due to its high mortality rates and multifaceted origins, including hereditary factors and various clinical changes. It stands as the deadliest type of cancer and a significant cause of cancer-related deaths globally. early diagnosis enables healthcare providers to administer appropriate treatment measures promptly and accurately, leading to improved prognosis and higher survival rates. The significant increase in both the incidence and mortality rates of lung cancer, particularly its ranking as the second most prevalent cancer among women worldwide, underscores the need for comprehensive research into efficient screening methods. Advances in diagnostic techniques, particularly the use of computed tomography (CT) scans, have revolutionized the identification of lung cancer. CT scans are renowned for their ability to provide high-resolution images and are particularly effective in detecting small, calcified areas, crucial for identifying early-stage lung cancer. Consequently, there is growing interest in enhancing computer-aided detection (CAD) systems. These algorithms assist radiologists by reducing false-positive interpretations and improving the accuracy of early cancer diagnosis. This study aims to enhance the effectiveness of CAD systems through various methods. Initially, the Contrast Limited Adaptive Histogram equalization (CLAHe) algorithm is employed to preprocess CT scan images, thereby improving their visual quality. further refinement is achieved by integrating different optimization strategies with the CLAHe method. The CutMix data augmentation technique is applied to boost the performance of the proposed model. A comparative analysis is conducted using deep learning architectures such as Inception-V3, ResNet101, Xception, and efficientNet. The study evaluates the performance of these architectures in image classification tasks, both with and without the implementation of the CLAHe algorithm. The em

关键词： CLAHe algorithm classification deep learning feature extraction healthcare applications Lung cancer detection optimization

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Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(english edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDeLAN M.MOHAMMADIMeHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

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乳腺数字化断层摄影分析乳腺实质结构评估罹患乳腺癌风险:与乳腺数字化摄影比较

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国际医学放射学杂志 2011年第6期 587-587页

作者： D.Kontos L.C.Ikejimba P.R.Bakic A.B.Troxel e.f.conant A.D.A.Maidment 张小玲 Department of Radiology University of Pennsylvania Health System1 Silverstein Bldg HUP3400 Spruce StPhiladelphia PA 19104-4206

目的乳腺密度百分比(PD)是已被确认的罹患乳腺癌的风险因子,本研究目的是在筛查人群中评估数字化乳腺断层摄影(DBT)与数字化乳腺摄影显示的乳腺实质结构特征与PD的相关性。材料与方法本研究经专业委员会核准,受试者均签署书面知情同意... 详细信息

目的乳腺密度百分比(PD)是已被确认的罹患乳腺癌的风险因子,本研究目的是在筛查人群中评估数字化乳腺断层摄影(DBT)与数字化乳腺摄影显示的乳腺实质结构特征与PD的相关性。材料与方法本研究经专业委员会核准,受试者均签署书面知情同意书。回顾性分析2007年7月—2008年3月进行的一项经专业委员会批准的DBT筛查

关键词：乳腺癌 DBT 乳腺肿瘤乳腺实质数字化乳腺摄影断层摄影

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Prospective cohort study on facial profile changes in infants with Robin sequence and healthy controls

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World Journal of Pediatrics 2024年第6期20卷 581-589页

作者： Cornelia Wiechers Julian Sowula Karen Kreutzer Christoph e.Schwarz Christina Weismann Michael Krimmel Christian f.Poets Bernd Koos Department of Neonatology Tuebingen University HospitalCalwerstrasse 772076 TuebingenGermany Center for Cleft Lip Palate and Craniofacial MalformationsTuebingen University HospitalTuebingenGermany Department of Orthodontics Tuebingen University HospitalTuebingenGermany Department of Oral and Maxillofacial Surgery Tuebingen University HospitalTuebingenGermany

Background Various conservative and surgical approaches exist to treat Robin sequence(RS),but their effects on facial profile and mandibular catch-up growth are unclear.A functional treatment concept,used in our centre for 25 years,includes an individualized palatal plate with a velo-pharyngeal extension and intensive feeding *** We performed a prospective study to objectively describe facial profiles in infants with RS treated with the above *** with isolated RS were admitted to our tertiary perinatal and national referral centre for craniofacial malformations between May 2018 and Nov *** with RS received 3D-photographs during clinically indicated *** controls were recruited from Dec 2018 to Sep 2019 and received 3D-photographs every 3 *** digitally measured jaw index(JI),defined as alveolar overjet(O)x maxillary arch(U)/mandibular arch(L),and the soft tissue reference points A’-point,Nasion’,B’-point angle(ANB’),describing the relative position of maxilla to mandible,were *** mixed models were used to examine time trajectories in JI and ANB’.Results A total of 2073D images,obtained in 19 infants with RS and 32 controls,were *** and ANB’decreased over time in both groups[for JI−0.18(95%CI−0.25 to−0.10);for ANB’:−0.40°per month[(95%CI−0.48 to−0.32)]]but remained lower in controls[for JI−2.5(95%CI−3.2 to−1.8);for ANB’-1.7°(95%CI−2.4 to−1.0)].Also,the ANB’model showed a significant effect of the interaction term diagnosis x *** Based on longitudinal 3D images,we describe changes in objective parameters of facial profile in infants with and without RS during the first year of *** findings indicate catch-up growth in infants treated for RS.

关键词： Infant Mandibular catch-up growth Pre-epiglottic Baton Plate Robin sequence Three-dimensional photography

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