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Virginia Tech Comprehensive Power-based Fuel Consumption Model(VT-CPFM):Model Validation and Calibration Considerations
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作者 Sangjun Park Hesham A.Rakha +1 位作者 Kyoungho Ahn Kevin Moran 《International Journal of Transportation Science and Technology》 2013年第4期317-336,共20页
A power-based vehicle fuel consumption model,entitled the Virginia Tech Comprehensive Power-based Fuel Consumption Model(VT-CPFM)that was developed in an earlier publication is validated against in-field fuel consumpt... A power-based vehicle fuel consumption model,entitled the Virginia Tech Comprehensive Power-based Fuel Consumption Model(VT-CPFM)that was developed in an earlier publication is validated against in-field fuel consumption measurements.The study demonstrates that the VT-CPFMs calibrated using the EPA city and highway fuel economy ratings generally provide reliable fuel consumption estimates with a coefficient of determination in the range of 0.96.More importantly,both estimates and measurements produce very similar behavioral changes depending on engine load conditions.The VT-CPFMs are demonstrated to be easily calibrated using publically available data without the need to gather in-field instantaneous data. 展开更多
关键词 CONSUMPTION POWER ESTIMATES
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Use of gene-editing technology to introduce targeted modifications in pigs 被引量:7
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作者 Junghyun Ryu Randall S.Prather Kiho Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第2期268-277,共10页
Pigs are an important resource in agriculture and serve as a model for human diseases. Due to their physiological and anatomical similarities with humans, pigs can recapitulate symptoms of human diseases, making them ... Pigs are an important resource in agriculture and serve as a model for human diseases. Due to their physiological and anatomical similarities with humans, pigs can recapitulate symptoms of human diseases, making them a useful model in biomedicine. However, in the past pig models have not been widely used partially because of the difficulty in genetic modification. The lack of true embryonic stem cells in pigs forced researchers to utilize genetic modification in somatic cells and somatic cell nuclear transfer(SCNT) to generate genetically engineered(GE) pigs carrying site-specific modifications. Although possible, this approach is extremely inefficient and GE pigs born through this method often presented developmental defects associated with the cloning process. Advancement in the gene-editing systems such as Zinc-Finger Nucleases(ZFNs), Transcription activator-like effector nucleases(TALENs), and the Clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associated 9(Cas9) system have dramatically increased the efficiency of producing GE pigs. These gene-editing systems, specifically engineered endonucleases, are based on inducing double-stranded breaks(DSBs) at a specific location, and then site-specific modifications can be introduced through one of the two DNA repair pathways: non-homologous end joining(NHEJ) or homology direct repair(HDR).Random insertions or deletions(indels) can be introduced through NHEJ and specific nucleotide sequences can be introduced through HDR, if donor DNA is provided. Use of these engineered endonucleases provides a higher success in genetic modifications, multiallelic modification of the genome, and an opportunity to introduce site-specific modifications during embryogenesis, thus bypassing the need of SCNT in GE pig production. This review will provide a historical prospective of GE pig production and examples of how the gene-editing system, led by engineered endonucleases, have improved GE pig production. We wil also present some of our current progress related to the optimal use of CRISPR/Cas9 system during embryogenesis. 展开更多
关键词 CRISPR/Cas9 Gene-editing Genetic engineering KNOCK-IN KNOCKOUT Pig TALEN ZFN
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The State-of-the-Art Review on Applications of Intrusive Sensing,Image Processing Techniques,and Machine Learning Methods in Pavement Monitoring and Analysis 被引量:23
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作者 Yue Hou Qiuhan Li +5 位作者 Chen Zhang Guoyang Lu Zhoujing Ye Yihan Chen Linbing Wang Dandan Cao 《Engineering》 SCIE EI 2021年第6期845-856,共12页
In modern transportation,pavement is one of the most important civil infrastructures for the movement of vehicles and pedestrians.Pavement service quality and service life are of great importance for civil engineers a... In modern transportation,pavement is one of the most important civil infrastructures for the movement of vehicles and pedestrians.Pavement service quality and service life are of great importance for civil engineers as they directly affect the regular service for the users.Therefore,monitoring the health status of pavement before irreversible damage occurs is essential for timely maintenance,which in turn ensures public transportation safety.Many pavement damages can be detected and analyzed by monitoring the structure dynamic responses and evaluating road surface conditions.Advanced technologies can be employed for the collection and analysis of such data,including various intrusive sensing techniques,image processing techniques,and machine learning methods.This review summarizes the state-ofthe-art of these three technologies in pavement engineering in recent years and suggests possible developments for future pavement monitoring and analysis based on these approaches. 展开更多
关键词 Pavement monitoring and analysis The state-of-the-art review Intrusive sensing Image processing techniques Machine learning methods
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Mercury concentrations in blood and feathers of nestling Bald Eagles in coastal and inland Virginia 被引量:2
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作者 David E.Kramar Bill Carstensen +1 位作者 Steve Prisley Jim Campbell 《Avian Research》 CSCD 2019年第1期36-42,共7页
Background:Mercury(Hg) and methylmercury are widely considered significant issues for wildlife,and in particular,piscivorous birds due to their widespread availability and neurotoxic properties.Whereas a substantial n... Background:Mercury(Hg) and methylmercury are widely considered significant issues for wildlife,and in particular,piscivorous birds due to their widespread availability and neurotoxic properties.Whereas a substantial number of studies of Hg contamination of Bald Eagles(Haliaeetus leucocephalus) have been conducted throughout the east coast of the United States,little has been done that directly addresses Hg contamination in Bald Eagles in Virginia,particularly the inland population.Methods:We collected blood and feather samples from nestling Bald Eagles in the coastal plain,piedmont,and western regions of Virginia in an effort to determine which areas of the state were more likely to contain populations showing evidence of Hg toxicity.We analyzed the samples for total Hg using a Milestone DMA-80.Results:Samples collected from individuals located in the coastal region exhibited low concentrations of Hg compared to those further inland located on freshwater rivers and reservoirs.Samples collected from the inland population exhibited levels in some areas that are approaching what may be considered to be sub-lethal to avian health(blood:mean 0.324 mg/kg,SE = 0.13,range = 0.06-0.97 mg/kg;feather:mean = 8.433 mg/kg,SE = 0.3,range = 3.811-21.14 mg/kg).Conclusions:Even after accounting for known point-sources of Hg,the inland eagle population in Virginia is susceptible to concentrations of Hg that are significantly higher than their coastal counterparts.Moreover,several locations besides those currently known to be impacted by point-sources are exhibiting concentrations that are approaching a sub-lethal level. 展开更多
关键词 Bald EAGLE Haliaeetus leucocephalus MERCURY Methyl-mercury VIRGINIA
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Hypothetical Commercialization of Biotech Soybeans in China: Impacts on Domestic Markets and International Trade 被引量:3
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作者 Francis Tuan James Hansen +3 位作者 Agapi Somwaru Mary Marchant Nicholas Kalaitzandonakes Funing Zhong 《Journal of Life Sciences》 2010年第3期52-60,共9页
China is the leading importer of soybeans in the world. If China adopts high yield biotech soybean varieties, China's soybean production would increase significantly and this would impact global soybean markets. This... China is the leading importer of soybeans in the world. If China adopts high yield biotech soybean varieties, China's soybean production would increase significantly and this would impact global soybean markets. This paper assesses the possible effects of adoption of herbicide-tolerant, biotech soybeans in China and its impact on the world soybean trade. Results indicate that under a low technology fee and high adoption rate, China would be able to satisfy its soybean food demand. Urban consumers' strong preference for non-biotech soybean oil may lead to increase in imports of non-biotech soybeans. 展开更多
关键词 China biotech soybeans partial equilibrium model trade effect.
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Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,Virginia,USA
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作者 Lauren V.Austin Alexander Silvis +1 位作者 W.Mark Ford Karen E.Powers 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1255-1270,共16页
Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire... Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat populations.Historic wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn programs.To examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),Virginia,USA.There was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)occupancy.Overall,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy approach.Our results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians. 展开更多
关键词 Appalachian mountains Bats False-positive occupancy Prescribed fire WILDFIRE
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Persistent diarrhea with petechial rash-unusual pattern of light chain amyloidosis deposition on skin and gastrointestinal biopsies:A case report
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作者 Shawna E Bilton Nikhil Shah +4 位作者 Diana Dougherty Sarah Simpson Alex Holliday Farhad Sahebjam Douglas J Grider 《World Journal of Clinical Cases》 SCIE 2022年第28期10252-10259,共8页
BACKGROUND Amyloidosis is a rare disease characterized by extracellular deposition of misfolded protein aggregated into insoluble fibrils.Gastrointestinal involvement in systemic amyloidosis is common,but is often sub... BACKGROUND Amyloidosis is a rare disease characterized by extracellular deposition of misfolded protein aggregated into insoluble fibrils.Gastrointestinal involvement in systemic amyloidosis is common,but is often subclinical or presents as vague and nonspecific symptoms.It is rare for gastrointestinal symptoms to be the main presenting symptom in patients with systemic amyloidosis,causing it to be undiagnosed until late-stage disease.CASE SUMMARY A 53 year-old man with diarrhea,hematochezia,and weight loss presented to a community hospital.Colonoscopy with biopsy at that time was suspicious for Crohn disease.Due to worsening symptoms including nausea,vomiting,and a new petechial rash,an abdominal fat pad biopsy was done.The biopsy showed papillary and adnexal dermal amyloid deposition,in a pattern usually seen with cutaneous amyloidosis.However,Cytokeratin 5/6 was negative,excluding cutaneous amyloidosis.The patterns of nodular amyloidosis,subcutaneous amyloid deposits and perivascular amyloid were not seen.Periodic Acid-Schiff stain was negative for lipoid proteinosis,Congo red was positive for apple green birefringence on polarization and amyloid typing confirmed amyloid light chain amyloidosis.Repeat endoscopic biopsies of the gastrointestinal tract showed amyloid deposition from the esophagus to the rectum,in a pattern usually seen in serum amyloid A in the setting of chronic inflammatory diseases,including severe inflammatory bowel disease.Bone marrow biopsy showed kappa-restricted plasma cell neoplasm.CONCLUSION Described is an unusual presentation of primary systemic amyloidosis,highlighting the risk of misdiagnosis with subsequent significant organ dysfunction and high mortality. 展开更多
关键词 Light chain amyloidosis DIARRHEA Endoscopy Petechial rash Plasma cell dyscrasia Case report
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Grain Consumption and Production in Virginia: A Trend and Spatial Examination
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作者 Peter Caffarelli Gustavo Ferreira +1 位作者 Gordon Groover Kathryn Boys 《Agricultural Sciences》 2016年第4期250-269,共20页
This article couples an examination of grain production with Virginia’s livestock and poultry sector to analyze the overall magnitude and distribution of grain consumption in Virginia. Specifically, this paper descri... This article couples an examination of grain production with Virginia’s livestock and poultry sector to analyze the overall magnitude and distribution of grain consumption in Virginia. Specifically, this paper describes the sources and trends over time of grain production and consumption;identifies grain surplus (and deficit) areas across Virginia’s counties;describes and applies a methodology to quantify livestock and poultry consumption requirements at the state- and county-levels;provides an updated assessment of Virginia’s ability to meet its feed grain needs;and discusses implications on the overall distribution system. Important results of the analysis reveal that grain consumption in Virginia is due mainly to demand in the poultry sector (primarily broilers and chickens). Furthermore, grain consumption in this state has generally declined over the last twenty years, due to decreasing livestock population numbers. Coupled with a slight upward trend in grain production, Virginia appears to be increasingly capable of meeting its grain needs. There is, however, an important east-west divide in the state, with western counties requiring more grain than they produce. Since grain does not appear to move from the relatively “production-rich” eastern counties, transportation infrastructure is important to bring in grain from outside the state. 展开更多
关键词 Animal Feed-Grain COUNTY Grain Consuming Animal Unit
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功率模块多物理场快速求解技术综述
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作者 祝令瑜 唐义政 +3 位作者 占草 康子章 王伟丞 汲胜昌 《高电压技术》 北大核心 2025年第10期4881-4899,共19页
功率模块作为电能变换系统的核心组件,其可靠性直接决定着新能源发电、高压直流输电等系统的安全稳定性。多物理场建模与分析是揭示功率模块运行状态与劣化机理的核心手段,然而传统数值计算方法存在计算效率瓶颈,难以满足新型电力系统... 功率模块作为电能变换系统的核心组件,其可靠性直接决定着新能源发电、高压直流输电等系统的安全稳定性。多物理场建模与分析是揭示功率模块运行状态与劣化机理的核心手段,然而传统数值计算方法存在计算效率瓶颈,难以满足新型电力系统对设备状态实时感知与智能诊断的需求。为此,该文总结了焊接型和压接型功率模块封装形式与多物理场建模方法;从物理模型降阶、投影降阶和深度学习降阶3个方面总结功率模块快速求解技术的研究现状,讨论了多物理场耦合模型的局部降阶方法,对比分析了各种快速求解技术的优缺点。在此基础上,进一步探讨目前迫切需要研究的重点,对进一步深入多物理场快速求解、数字孪生、智慧运维等研究具有重要的参考价值。 展开更多
关键词 功率模块 多物理场耦合 快速求解 物理模型降阶 投影降阶 深度学习
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Evaluation of Two Methods of Production and Release of the Parasitoid Habrobracon hebetor Say (Hymenoptera: Braconidae) for the Control of Pearl Millet Head Miner Heliocheilus albipunctella (de Joannis) (Lepidoptera: Noctuidae) in Maradi (Niger)
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作者 Laouali Amadou Mahaman Nassirou Oumarou +5 位作者 Ousseina Abdoulaye Souleymane Laminou Issa Yacouba Ibrahim Baoua Malick N. Ba Rangaswamy Muniappan 《Advances in Entomology》 2025年第1期126-138,共13页
Pearl millet, Pennisetum glaucum (Leeke) R. Br, is the main cereal crop in Niger. This crop is seriously attacked by the millet Head miner (MHM), Heliocheilus albipunctella (de Joannis) (Lepidoptera, Noctuidae) causin... Pearl millet, Pennisetum glaucum (Leeke) R. Br, is the main cereal crop in Niger. This crop is seriously attacked by the millet Head miner (MHM), Heliocheilus albipunctella (de Joannis) (Lepidoptera, Noctuidae) causing significant yield losses. This study to optimize biological control of this pest was carried out in Niger in the laboratory and in a farming environment. In the laboratory, the larval paralysis and emergence of the parasitoid Habrobracon hebetor Say (Hymenoptera: Braconidae) were compared between release jute bags, plastic boxes and cardboard boxes. In a farming environment, direct releases were carried out with plastic boxes and releases with jute bags in 12 villages of the Maradi region during the cropping seasons of 2021 and 2022. The results indicated that 25 larvae of Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) in the boxes were all paralyzed by 2 females of H. hebetor within 7 hours 30 minutes. The emergence of adults began on the 7th day after the beginning of the experiment for a period of two weeks and three weeks respectively in the boxes and jute bags. The production varied from 107.08 to 110.17 parasitoids and was comparable between the Jute bags, plastic boxes and cardboard boxes. In Farmers’ fields, the parasitoid release with the two methods caused the parasitism rates that varied from 64.32 to 66.52% depending on the year but in 2022 the rate of parasitism was higher in the fields with direct releases using plastic boxes (72.66%) compared to those released with jute bags (56.35%). Plastic boxes and cardboard boxes can be used for the production of the H. hebetor parasitoids. These results can be recommended to the cottage industries in the Sahel in order to improve the production and release methods of H. hebetor and make them more adapted to farmers’ fields. 展开更多
关键词 Biological Control Parasitoid Release Hebrobracon hebetor Heliocheilus albipunctella NIGER
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Kinetic Monte Carlo modelling of nano-oxide precipitation and its associated stability under neutron irradiation for the Fe-Ti-Y-O system
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作者 Chris Nellis Céline Hin 《Journal of Materials Science & Technology》 2025年第19期40-54,共15页
While developing nuclear materials,predicting their behavior under long-term irradiation regimes span-ning decades poses a significant challenge.We developed a novel Kinetic Monte Carlo(KMC)model to explore the precip... While developing nuclear materials,predicting their behavior under long-term irradiation regimes span-ning decades poses a significant challenge.We developed a novel Kinetic Monte Carlo(KMC)model to explore the precipitation behavior of Y-Ti-O oxides along grain boundaries within nanostructured ferritic alloys(NFA).This model also assessed the response of the oxides to neutron irradiation,even up sim-ulated radiation damage levels in the desired long dpa range for reactor components.Our simulations investigated how temperature and grain boundary sinks influenced the oxide characteristics of a 12YWT-like alloy during heat treatments at 1023,1123,and 1223 K.The oxide characteristics observed in our simulations were in good agreement with existing literature.Furthermore,the impact of grain bound-aries on precipitation was found to be minimal.The resulting oxide configurations and positions were used in subsequent simulations that exposed them to simulated neutron irradiation to a total accumu-lated dose of 8 dpa at three temperatures:673,773,and 873 K,and at dose rates of 10-3,10-4,and 10-5 dpa/s.This demonstrated the expected inverse relationship between oxide size and dose rate.In a long-term irradiation simulation at 873 K and 10-3 dpa/s was taken out to 66 dpa and found the oxides in the vicinity of the grain boundary were more susceptible to dissolution.Additionally,we conducted irradia-tion simulations of a 14YWT-like alloy to reproduce findings from neutron irradiation experiments.The larger oxides in the 14YWT-like alloy did not dissolve and displayed stability similar to the experimental results. 展开更多
关键词 Ostwald ripening ODS ferritic steel Monte Carlo simulation Irradiated metals
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Cross Slip and Twinning During Torsion Around α-Axis of Magnesium
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作者 Qi Pan Shichong Zhou +1 位作者 Fangxi Wang Peng Chen 《Acta Metallurgica Sinica(English Letters)》 2025年第8期1410-1420,共11页
Magnesium(Mg)alloys are usually subjected to torsion deformation during processing or manufacturing.However,the torsional behavior remains underexplored at the atomic level compared to uniaxial deformation.In this wor... Magnesium(Mg)alloys are usually subjected to torsion deformation during processing or manufacturing.However,the torsional behavior remains underexplored at the atomic level compared to uniaxial deformation.In this work,atomistic simulations are employed to understand the deformation mechanism during torsion around <1010>and<1120>axes of Mg.We reveal that the onset of plasticity occurs near the surface due to stress-gradient effect and the deformation mechanisms are highly dependent on torsion axis.Specifically,the prismatic and basal slip dominate torsion around[1120]axis.During torsion around[1010]axis,{1121}twinning can be activated,whereas{1011}twinning is formed due to local stress but detwinned eventually.Moreover,extensive cross slip and interactions between basal and prismatic dislocations are observed and the associated mechanisms are discussed.These novel atomic-scale insights provide deeper understanding of the plastic deformation mechanisms of Mg under torsional loading. 展开更多
关键词 MAGNESIUM Cross slip Torsional deformation Molecular dynamics
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Migrating Populus with climate change:Phenology,coppice management,cold spell susceptibility,leaf dynamics,and biomass production
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作者 Jiaxin Wang Randall J.Rousseau +3 位作者 Austin Himes Courtney Siegert Ying Ouyang Heidi J.Renninger 《Forest Ecosystems》 2025年第5期863-876,共14页
Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change.We investigated leaf budbreak timing,susceptibility to cold damage,le... Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change.We investigated leaf budbreak timing,susceptibility to cold damage,leaf dynamics,and biomass production of 168 Populus genotypes with diverse provenances in the southeastern United States.Our study revealed significant variation in budbreak timing across different taxa and years,with genotypes inheriting traits adapted to their parents’local climates.Temperature emerged as a key factor triggering budbreak,while leaf development depended on other environmental cues such as photoperiod.Notably,budbreak occurred approximately 20 days earlier in 2023 compared to 2022 due to higher accumulated degree days(ADDs).Short-rotation-coppice(SRC)management delayed budbreak by five to ten days.Cold damage was significant in 2023,particularly for genotypes from northern provenances and those with P.maximowiczii parentage.Severe damage was also observed in eastern cottonwood(Populus deltoides×Populus deltoides(D×D))genotypes,despite most having southeastern US parentages.Leaf dynamics,including leaf duration and leaf area index(LAI),varied across taxa and sites,with earlier budbreak correlating with extended growing seasons and increased LAI.Biomass production was intricately linked to phenological events,with earlier budbreak leading to increased biomass production and greater susceptibility to cold damage.Our findings highlight the importance of genetics,environment,and coppicing management in understanding and managing Populus phenology and biomass production.These insights provide valuable guidance for developing effective breeding,conservation,and management strategies for Populus species in the context of climate change. 展开更多
关键词 Accumulated degree days(ADDs) PHOTOPERIOD Provenance Spring budbreak Spring frost damage Short-rotation-coppice(SRC)
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Scale-invariant 3D face recognition using computer-generated holograms and the Mellin transform
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作者 Yongwei Yao Yaping Zhang +3 位作者 Huanrong He Xianfeng David Gu Daping Chu Ting-Chung Poon 《Opto-Electronic Advances》 2025年第11期43-55,共13页
We present a novel method for scale-invariant 3D face recognition by integrating computer-generated holography with the Mellin transform.This approach leverages the scale-invariance property of the Mellin transform to... We present a novel method for scale-invariant 3D face recognition by integrating computer-generated holography with the Mellin transform.This approach leverages the scale-invariance property of the Mellin transform to address challenges related to variations in 3D facial sizes during recognition.By applying the Mellin transform to computer-generated holograms and performing correlation between them,which,to the best of our knowledge,is being done for the first time,we have developed a robust recognition framework capable of managing significant scale variations without compromising recognition accuracy.Digital holograms of 3D faces are generated from a face database,and the Mellin transform is employed to enable robust recognition across scale factors ranging from 0.4 to 2.0.Within this range,the method achieves 100%recognition accuracy,as confirmed by both simulation-based and hybrid optical/digital experimental validations.Numerical calculations demonstrate that our method significantly enhances the accuracy and reliability of 3D face recognition,as evidenced by the sharp correlation peaks and higher peak-to-noise ratio(PNR)values than that of using conventional holograms without the Mellin transform.Additionally,the hybrid optical/digital joint transform correlation hardware further validates the method's effectiveness,demonstrating its capability to accurately identify and distinguish 3D faces at various scales.This work provides a promising solution for advanced biometric systems,especially for those which require 3D scale-invariant recognition. 展开更多
关键词 3D face recognition computer-generate holography Mellin transform scale invariance BIOMETRICS
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Mesenchymal stem cell-based therapy for peripheral nerve injuries: A promise or reality?
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作者 Lucas Vinicius de Oliveira Ferreira Kelly Cristine Santos Roballo Rogerio Martins Amorim 《World Journal of Stem Cells》 2025年第6期27-44,共18页
Peripheral nerve injuries(PNI)that result in nerve gaps represent a major clinical challenge,frequently leading to long-term disability and a diminished quality of life for affected individuals.Despite advances in sur... Peripheral nerve injuries(PNI)that result in nerve gaps represent a major clinical challenge,frequently leading to long-term disability and a diminished quality of life for affected individuals.Despite advances in surgical techniques,functional recovery remains limited,highlighting the need for innovative therapeutic strategies.Mesenchymal stem cells(MSCs)have emerged as a promising avenue for nerve repair due to their regenerative,immunomodulatory,and neuropro-tective properties.Thus,this review explored current approaches utilizing MSCs in the treatment of PNI,emphasizing their potential to enhance nerve rege-neration and functional recovery.Furthermore,tissue engineering and transdiffer-entiation of MSCs into Schwann-like cells offer a versatile strategy to optimize therapeutic effects,paving the way for personalized medicine.Nevertheless,challenges persist regarding the clinical application of MSCs in PNI,including transplant safety,delivery methods,optimal dosing,and ethical considerations.A deeper understanding of the mechanisms underlying MSC action in PNI may contribute to more effective treatment protocols in the management of peripheral nerve defects. 展开更多
关键词 Cell-based therapies Extracellular vesicles Mesenchymal stem cells Nerve guidance conduits Nerve regeneration Regenerative medicine
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Acoustofluidics-Based Intracellular Nanoparticle Delivery
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作者 Zhishang Li Zhenhua Tian +18 位作者 Jason N.Belling Joseph T.Rich Haodong Zhu Zhehan Ma Hunter Bachman Liang Shen Yaosi Liang Xiaolin Qi Liv K.Heidenreich Yao Gong Shujie Yang Wenfen Zhang Peiran Zhang Yingchun Fu Yibin Ying Steven J.Jonas Yanbin Li Paul S.Weiss Tony J.Huang 《Engineering》 2025年第4期130-138,共9页
Controlled intracellular delivery of biomolecular cargo is critical for developing targeted therapeutics and cell reprogramming.Conventional delivery approaches(e.g.,endocytosis of nano-vectors,microinjection,and elec... Controlled intracellular delivery of biomolecular cargo is critical for developing targeted therapeutics and cell reprogramming.Conventional delivery approaches(e.g.,endocytosis of nano-vectors,microinjection,and electroporation)usually require time-consuming uptake processes,labor-intensive operations,and/or costly specialized equipment.Here,we present an acoustofluidics-based intracellular delivery approach capable of effectively delivering various functional nanomaterials to multiple cell types(e.g.,adherent and suspension cancer cells).By tuning the standing acoustic waves in a glass capillary,our approach can push cells in flow to the capillary wall and enhance membrane permeability by increasing membrane stress to deform cells via acoustic radiation forces.Moreover,by coating the capillary with cargo-encapsulated nanoparticles,our approach can achieve controllable cell-nanoparticle contact and facilitate nanomaterial delivery beyond Brownian movement.Based on these mechanisms,we have successfully delivered nanoparticles loaded with small molecules or protein-based cargo to U937 and HeLa cells.Our results demonstrate enhanced delivery efficiency compared to attempts made without the use of acoustofluidics.Moreover,compared to conventional sonoporation methods,our approach does not require special contrast agents with microbubbles.This acoustofluidics-based approach creates exciting opportunities to achieve controllable intracellular delivery of various biomolecular cargoes to diverse cell types for potential therapeutic applications and biophysical studies. 展开更多
关键词 Acoustofluidics SONOPORATION NANOCARRIERS Metal-organic frameworks
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基于阻抗谱的脉冲电场诱导兔肝脏组织不可逆电穿孔程度评估新方法的实验研究 被引量:5
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作者 姚陈果 赵亚军 +5 位作者 董守龙 Suyashree Bhonsle 吕彦鹏 刘红梅 马剑豪 Rafael Davalos 《高电压技术》 EI CAS CSCD 北大核心 2017年第8期2454-2463,共10页
不可逆电穿孔肿瘤消融的有效性与安全性已经过多年的临床应用而得到验证,新近发展起来的高频不可逆电穿孔肿瘤消融新方法兼具传统不可逆电穿孔的优势和缓解肌肉收缩的长处,然而目前对其作用机理还未深入研究。为此,从阻抗谱分析角度分... 不可逆电穿孔肿瘤消融的有效性与安全性已经过多年的临床应用而得到验证,新近发展起来的高频不可逆电穿孔肿瘤消融新方法兼具传统不可逆电穿孔的优势和缓解肌肉收缩的长处,然而目前对其作用机理还未深入研究。为此,从阻抗谱分析角度分析了高频不可逆电穿孔与传统不可逆电穿孔组织消融的差异性,研究了相同剂量下高频不可逆电穿孔与传统不可逆电穿孔消融新西兰大白兔肝脏组织引起的组织阻抗谱变化,并通过等效电路的拟合提取了阻抗谱变化中的信息。研究结果表明:脉冲处理后组织阻抗谱显著变化,阻抗模在中低频段显著减小,阻抗角在中高频段从负值向零值方向变化;通过等效电路拟合发现,处理后显著变化的是细胞外液等效电阻,由于细胞膜穿孔而增加了新的与细胞外液等效电阻并联的电流通路;脉冲剂量相同条件下,传统不可逆电穿孔脉冲作用引起的细胞外液等效电阻变化最大,高频不可逆电穿孔作用下,脉冲宽度越宽,细胞外液等效电阻变化就越显著。因此,组织阻抗谱变化及由它得到的等效电路元器件值变化,可以有效地反映电穿孔程度,有望成为临床应用中检测不可逆电穿孔治疗效果的有效方式。 展开更多
关键词 高频不可逆电穿孔 组织消融 阻抗谱 肿瘤治疗 等效电路 脉冲电场
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基于定量古地理的BQART模型深时古地势重建方法——以晚二叠世峨眉山大火成岩省内带为例 被引量:3
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作者 王学天 邵龙义 +3 位作者 Kenneth A.Eriksson 胡修棉 刘钦甫 鲁静 《沉积学报》 CAS CSCD 北大核心 2022年第6期1461-1480,共20页
源—汇系统分析下的古地势重建是当前沉积学领域的一个热点方向。古地势重建对于理解区域构造演化、气候变化、地表风化、物源供给及其相互关系具有重要作用。BQART沉积通量模型提供了入海流域中沉积通量与地质背景B、水流量Q、流域面积... 源—汇系统分析下的古地势重建是当前沉积学领域的一个热点方向。古地势重建对于理解区域构造演化、气候变化、地表风化、物源供给及其相互关系具有重要作用。BQART沉积通量模型提供了入海流域中沉积通量与地质背景B、水流量Q、流域面积A、最大地势高度R、年均温度T之间的经验关系,逐渐发展为深时尺度下古流域地势重建的重要工具。本文在综合层序—古地理、旋回地层学、古水文比例关系和古地貌比例关系等方法的基础上,提出基于定量古地理的BQART模型深时古地势重建方法,结合沉积体积回填法可进一步获得构造抬升幅度与速率。通过该方法获得峨眉山大火成岩省内带古地势在晚二叠世期间持续缓慢上升,至晚二叠世末达200余米,累计构造抬升幅度约500~750 m。该深时古地势方法适用于气候温暖湿润、构造相对稳定条件下的中大型外流盆地,对能源盆地的勘探开发具有重要意义。 展开更多
关键词 BQART模型 沉积通量 定量古地理 源—汇系统 古地势 晚二叠世 峨眉山大火成岩省
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电力电子中高频软磁材料的研究进展 被引量:14
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作者 刘君昌 梅云辉 陆国权 《材料工程》 EI CAS CSCD 北大核心 2017年第5期127-134,共8页
随着电力电子行业的飞速发展,新型电磁材料的投入使用,对电子元器件的高频磁性能提出了新的要求。磁芯作为电子元器件的核心部件,其发展程度直接决定电子元器件的性能,这就要求具有优异高频软磁性能的材料发展。本文综述了四种软磁材料... 随着电力电子行业的飞速发展,新型电磁材料的投入使用,对电子元器件的高频磁性能提出了新的要求。磁芯作为电子元器件的核心部件,其发展程度直接决定电子元器件的性能,这就要求具有优异高频软磁性能的材料发展。本文综述了四种软磁材料的发展历程,对每种软磁材料的优缺点进行了归纳总结,同时指出了未来的发展方向,并重点对近年来研究热门的软磁复合材料进行了梳理。粒径大小可控、包覆层对核层的包覆均匀程度以及从实验室走向产业化的大批量制备方法是未来高频软磁复合材料的发展趋势。 展开更多
关键词 电力电子 软磁材料 高频低损 低矫顽力
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基于社交媒体分析的手机缺陷识别 被引量:6
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作者 张嵩 吴剑云 +1 位作者 樊卫国 刘树坤 《计算机集成制造系统》 EI CSCD 北大核心 2016年第9期2264-2273,共10页
为了从社交媒体中获取用户反映手机产品缺陷的数据信息,在对现有社交媒体分析框架进行改进的基础上,结合不同的平台特征,构建了基于社交媒体分析的手机产品缺陷识别框架;在综合分析比较后采用信息增益作为特征评估函数,利用支持向量机... 为了从社交媒体中获取用户反映手机产品缺陷的数据信息,在对现有社交媒体分析框架进行改进的基础上,结合不同的平台特征,构建了基于社交媒体分析的手机产品缺陷识别框架;在综合分析比较后采用信息增益作为特征评估函数,利用支持向量机分类方法对社交媒体数据进行情感识别,构建手机产品缺陷语料集;基于主题模型算法对手机产品缺陷进行聚类分析,形成不同的缺陷内容聚类。相关实验研究结果表明,该方法能够有效地识别出中文社交媒体中的手机缺陷,具有较高的准确率和召回率。 展开更多
关键词 社交媒体分析 缺陷识别 文本挖掘 手机
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