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Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei ZHANG Peng WANG Yongfeng DONG Linhao LI Xin LI School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

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Jumping droplets

Droplet 2024年第2期3卷 3-33页

作者： Jonathan B.Boreyko department of Mechanical Engineering Virginia TechBlacksburgVirginiaUSA

When microdroplets with quasi-spherical contact angles coalesce together on a low-adhesion substrate,the capillary-inertial expansion of the liquid bridge induces a dramatic out-of-plane jumping event due to symmetry *** the onset of merging,droplet jumping initiates after a capillary-inertial time scale of tci∼1–100μs with characteristic jumping speeds of order vj∼0.1m/*** coalescenceinduced jumping-droplet effect is most commonly observed among a population of growing dew droplets on a superhydrophobic condenser,but can also occur by colliding deposited droplets together or during droplet sliding on fog *** this review,we cover the historical development of capillary-inertial jumping droplets,summarize the decade-long effort to rationalize the ultra-low energy conversion efficiency and critical droplet size of the phenomenon,and then present 15 variations on a theme of ***-inertial jumping droplets are not only a visceral illustration of the surprising power of surface tension at the microscale but they also have the potential to enhance phase-change heat transfer,enable selfcleaning surfaces,combat frost formation,harvest energy,and govern the rate of disease spread for wheat crops.

关键词： capillary illustration rational

Generating synthetic as-built additive manufacturing surface topography using progressive growing generative adversarial networks

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Friction 2024年第6期12卷 1283-1298页

作者： Junhyeon SEO Prahalada RAO Bart RAEYMAEKERS department of Mechanical Engineering Virginia TechBlacksburgVA 24061USA Grado department of Industrial and Systems Engineering Virginia TechBlacksburgVA 24061USA

Numerically generating synthetic surface topography that closely resembles the features and characteristics of experimental surface topography measurements reduces the need to perform these intricate and costly ***,existing algorithms to numerically generated surface topography are not well-suited to create the specific characteristics and geometric features of as-built surfaces that result from laser powder bed fusion(LPBF),such as partially melted metal particles,porosity,laser scan lines,and ***,we present a method to generate synthetic as-built LPBF surface topography maps using a progressively growing generative adversarial *** qualitatively and quantitatively demonstrate good agreement between synthetic and experimental as-built LPBF surface topography maps using areal and deterministic surface topography parameters,radially averaged power spectral density,and material ratio *** ability to accurately generate synthetic as-built LPBF surface topography maps reduces the experimental burden of performing a large number of surface topography ***,it facilitates combining experimental measurements with synthetic surface topography maps to create large data-sets that facilitate,*** as-built surface topography to LPBF process parameters,or implementing digital surface twins to monitor complex end-use LPBF parts,amongst other applications.

关键词： additive manufacturing surface topography synthetic surface topography generative adversarial networks

Condition indices for rigid pavements: A comparative analysis of state DOTs using Michigan PMS data

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Journal of Road Engineering 2024年第3期4卷 348-360页

作者： Rahul Raj Singh Mumtahin Hasnat Muhammed Emin Kutay Syed Waqar Haider James Bryce Bora Cetin department of Civil and Environmental Engineering Michigan State UniversityEast LansingMI 48824USA Wadsworth department of Civil and Environmental Engineering West Virginia UniversityMorgantownWV 26506USA

Pavement infrastructure is vital in providing services and links between various sectors of society. Therefore, thepreservation and maintenance of these roads are critical to attaining a pavement network in good conditionthroughout its service life. Various performance indicators like the international roughness index (IRI), pavementcondition index (PCI), and present serviceability rating (PSR) have been used by the state department of transportation (DOT) and highway agencies for evaluating pavement surface conditions and planning future maintenance strategies. Limited data availability, multiple distresses depending on region, lack of correlation of thesecondition indices to maintenance strategies, and data collection limitations pose a challenge for applying theseindices to local conditions. This paper compares condition indices of different states for rigid pavements. Further,using a specific condition index for local conditions is also highlighted. For this purpose, five states and theircorresponding condition indices were evaluated and compared to the Michigan DOT distress index (DI). Thesestates include virginia, Minnesota, North Dakota, Louisiana, and Oregon. The corresponding distresses of eachcondition index were converted to make them compatible with the MDOT DI. This study used the MDOT'spavement management system (PMS) database to evaluate each condition index for 433 rigid pavement *** distress index was plotted against MDOT DI and compared using a paired t-test. Results show that thecondition indices of virginia and Minnesota are comparable to DI in terms of the Spearman correlation value. Thet-test results show that except for Virgina, condition indices from other states statistically differ from ***, one can't use those directly for local conditions in Michigan. This paper presents the evaluation anddata requirements for each condition index and its impact on selecting a maintenance treatment.

关键词： Rigid pavement Pavement management Condition index Distress index

Advancing respirable coal mine dust source apportionment:a preliminary laboratory exploration of optical microscopy as a novel monitoring tool

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International Journal of Coal Science & Technology 2024年第2期11卷 222-233页

作者： Nestor Santa Emily Sarver department of Mining and Minerals Engineering Virginia TechBlacksburgVA 24061USA

Exposure to respirable coal mine dust(RCMD)can cause chronic and debilitating lung ***-time monitoring capabilities are sought which can enable a better understanding of dust components and *** many underground mines,RCMD includes three primary components which can be loosely associated with three major dust sources:coal dust from the coal seam itself,silicates from the surrounding rock strata,and carbonates from the inert‘rock dust’products that are applied to mitigate explosion hazards.A monitor which can reliably partition RCMD between these three components could thus allow source *** tracking silicates,specifically,could be valuable since the most serious health risks are typically associated with this component-particularly if abundant in crystalline *** a monitoring concept based on field microscopy,and following up on prior research using polarized light,the aim of the current study was to build and test a model to classify respirable-sized particles as either coal,silicates,or *** model development,composite dust samples were generated in the laboratory by successively depositing dust from high-purity materials onto a sticky transparent substrate,and imaging after each deposition event such that the identity of each particle was known a *** testing followed a similar approach,except that real geologic materials were used as the source for each dust *** showed that the model had an overall accuracy of 86.5%,indicating that a field-microscopy based moni-tor could support RCMD source apportionment and silicates tracking in some coal mines.

关键词： Polarized light microscopy Image processing Dust monitoring Respirable silica Coal mining

Patients’experiences with‘sludge’(administrative burden)in the cancer screening process and its relationship with screening completion,experience and health system distrust

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Family Medicine and Community Health 2024年第S2期12卷 8-17页

作者： Michelle S Rockwell Brianna Chang Vivian Zagarese Jamie K Turner Ally Southworth YingXing Wu Paul Yeaton Li Li Jeffrey S Stein Sarah H Parker John W Epling department of Family and Community Medicine Virginia Tech Carilion School of MedicineRoanokeVirginiaUSA department of Family and Community Medicine Carilion ClinicRoanokeVirginiaUSA virginia Tech Carilion School of Medicine RoanokeVirginiaUSA department of Health Systems and Implementation Science Virginia Tech Carilion School of MedicineRoanokeVirginiaUSA Graduate Program in Translational Biology Medicineand HealthVirginia TechRoanokeVirginiaUSA Health Analytics Research Team Carilion ClinicRoanokeVirginiaUSA Division of Gastroenterology Department of Internal MedicineCarilion ClinicRoanokeVirginiaUSA department of Family Medicine University of Virginia School of MedicineCharlottesvilleVirginiaUSA Center for Health Behaviors Research Fralin Biomedical Research Institute at VTCRoanokeVirginiaUSA

Objective‘Sludge’refers to administrative burdens or frictions that preclude people from getting what they want or need(eg,duplicative forms,complicated instructions,long waiting times).This mixed methods study evaluated patients’perceptions of sludge in the colorectal cancer(CRC)screening process and some impacts of this *** We employed an exploratory sequential mixed methods study design that comprised patient interviews and a patient *** interviews informed final survey revisions and captured contextual data about patients’experiences with *** transcripts were inductively and deductively analysed to identify overarching *** survey quantified sludge,delayed or forgone screenings,screening experience(Net Promoter Score)and health system distrust(Health System Distrust Scale).We usedχ2 or t-tests for univariable comparisons and logistic or linear regressions to evaluate the association between cumulative sludge score and delayed or forgone screenings,screening experience and health system *** were integrated for *** Southeastern United *** Patients who were 45–75 years of age,at average risk for CRC and had either completed or been referred for CRC screening(colonoscopy or stool-based test)within the previous 12 *** 22 interview participants and 255 survey participants completed the study.38(15%)survey participants rated their screening experience as poor(Net Promoter Score=0–7 out of 10).The mean(SD)Health System Distrust Scale score was 22.4(6.3)out of 45 possible points(higher score=greater distrust).Perceptions of sludge in the CRC screening process varied,with long waiting times and burdensome communication being the most common sources(58%and 35%of participants,respectively).Sludge was positively associated with delayed or forgone screenings(OR=1.42,95%CI 1.28,1.57,p<0.001),poor screening experience(OR=1.15,95%CI 1.04,1.28,p=0.009)and health system distrust(β=0.47,p

关键词： sludge screening burden

Implementation of Fuzzy Logic Control into an Equivalent Minimization Strategy for Adaptive Energy Management of A Parallel Hybrid Electric Vehicle

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Journal of Transportation Technologies 2024年第1期14卷 88-118页

作者： Jared A. Diethorn Andrew C. Nix Mario G. Perhinschi W. Scott Wayne department of Mechanical and Aerospace Engineering West Virginia University Morgantown WV USA

As government agencies continue to tighten emissions regulations due to the continued increase in greenhouse gas production, automotive industries are seeking to produce increasingly efficient vehicle technology. Hybrid electric vehicles (HEVs) have been introduced to mitigate problems while improving fuel economy. HEVs have led to the demand of creating more advanced controls software to consider multiple components for propulsive power in a vehicle. A large section in the software development process is the implementation of an optimal energy management strategy meant to improve the overall fuel efficiency of the vehicle. Optimal strategies can be implemented when driving conditions are known a prior. The Equivalent Consumption Minimization Strategy (ECMS) is an optimal control strategy that uses an equivalence factor to equate electrical to mechanical power when performing torque split determination between the internal combustion engine and electric motor for propulsive and regenerative torque. This equivalence factor is determined from offline vehicle simulations using a sensitivity analysis to provide optimal fuel economy results while maintaining predetermined high voltage battery state of charge (SOC) constraints. When the control hierarchy is modified or different driving styles are applied, the analysis must be redone to update the equivalence factor. The goal of this work is to implement a fuzzy logic controller that dynamically updates the equivalence factor to improve fuel economy, maintain a strict charge sustaining window of operation for the high voltage battery, and reduce computational time required during algorithm development. The adaptive algorithm is validated against global optimum fuel economy and charge sustaining results from a sensitivity analysis performed for multiple drive cycles. Results show a maximum fuel economy improvement of 9.82% when using a mild driving style and a 95% success rate when maintaining an ending SOC within 5% of th

关键词： Hybrid Electric Vehicle Fuzzy Logic Adaptive Control Charge Sustainability

Robotic-assisted versus laparoscopic repair of type II, III and IV hiatal hernias: A retrospective study comparing adverse outcomes

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第1期7卷 11-15页

作者： Payton Kooiker Shane Monnett Stephanie Thompson Bryan Richmond west virginia School of Osteopathic Medicine LewisburgWV24901United States department of Surgery Charleston Area Medical CenterCharlestonWV25304United States

Objective:Robotic-assisted surgery(RAS)is continuing to expand in use in surgical specialties,including foregut *** available data on its use in large hiatal hernia(HH)repair are limited and *** study sought to determine whether there are significant differences in adverse outcomes following HH repair performed with a robotic approach vs.a laparoscopic *** study was limited to outcomes in patients with type II,III,and IV HHs,as these hernias are typically more challenging to ***:A retrospective analysis was performed from data obtained from TriNetX,a large deidentified clinical database,over a 10-year *** patients who underwent type II,III,or IV HH repair were included in the *** with robotic repair was compared to laparoscopic *** were propensity score matched for demographic information and *** ratios,risk differences(RDs)with 95%confidence intervals(CIs),and t test for each examined adverse outcome were used to estimate the effects of robotic repair *** ***:In total,20,016 patients who met the inclusion criteria were identified;1,515 patients utilized RAS,and 18,501 used *** to matching,there were significant differences in age,sex,comorbidity,and BMI between the two *** 1:1 propensity score matching,analyses of 1,514 well-matched patient pairs revealed no significant differences in demographics or *** who underwent robotic repair were more likely to experience major complications,including venous thromboembolism(RD:0.007,95%CI:0.003,0.011;p?0.002),critical care(RD:0.023,95%CI:0.007,0.039;p?0.004),urinary/renal complications(RD:0.027,95%CI:0.014,0.041;p<0.001),and respiratory complications(RD:0.046,95%CI:0.028,0.064;p<0.001).RAS was associated with a significantly shorter length of stay(32.4±27.5 h vs.35.7±50.1 h,p?0.031),although this finding indicated a reduction in the length of stay of less than 4 *** statist

关键词： Hiatal hernia Robotic-assisted surgery Laparoscopic surgery Adverse outcomes

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 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