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Motion visualization and estimation for flapping wing systems

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Acta Mechanica Sinica 2017年第2期33卷 327-340页

作者： Tzu-Sheng shane Hsu Timothy Fitzgerald Vincent Phuc Nguyen Trisha Patel Balakumar Balachandran Department of Mechanical Engineering University of Maryland College Park MD 20742 USA

Studies of fluid-structure interactions associated with flexible structures such as flapping wings require the capture and quantification of large motions of bodies that may be opaque. As a case study, motion capture of a free flying Manduca sexta, also known as hawkmoth, is considered by using three synchronized high-speed cameras. A solid finite element (FE) representation is used as a reference body and successive snapshots in time of the displacement fields are reconstructed via an optimization procedure. One of the original aspects of this work is the formulation of an objective function and the use of shadow matching and strain-energy regularization. With this objective function, the authors penalize the projection differences between silhouettes of the captured images and the FE representation of the deformed body. The process and procedures undertaken to go from high-speed videography to motion estimation are discussed, and snapshots of representative results are presented. Finally, the captured free-flight motion is also characterized and quantified.

关键词： Insect flight Deformable body High-speed videography Motion estimation

IAVcEI cEV-cVS field workshop： Phreatomagmatic volcanoes of Jeju Island, Korea

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Episodes 2008年第3期31卷 358-360页

作者： Nemeth, Karoly cronin, shane J. Massey Univ Volcan Risk Solut Inst Nat Resources Palmerston North New Zealand

A scientific field workshop sponsored by two commissions （commission on Explosive Volcanism -- cEV and commission on Vol- canogenic Sediments-cVS） of the Interna- tional Association of Volcanology and chemistry of the Earth Interior （IAVcEI） took place in Jeju Island, South Korea from 13-17 November 2007. This was organised by Prof. Dr. Young Kwan Sohn （Gyeongsan National University, Jinju） and Dr. Ki Hwa Park （Korea Institute of Geoscience and Mineral Resources, Daejon）. The ＂Phreato- magmatic volcanoes of Jeju Island,

关键词：地理学潜水岩浆互相作用韩国岛屿

Kinematic error modeling and error compensation of desktop 3D printer

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Nanotechnology and Precision Engineering 2018年第3期1卷 180-186页

作者： shane Keaveney Pat connolly Eoin D.O'cearbhaill School of Mechanical and Materials Engineering UCD Engineering and Materials Science CentreDublin 4Ireland

Desktop 3D printers have revolutionized how designers and makers prototype and manufacture certain *** popular fuse deposition modeling(FDM)desktop printers have enabled a shift to low-cost consumer goods markets,through reduced capital equipment investment and consumable material ***,with this drive to reduce costs,the computer numerical control(cNc)systems implemented in FDM printers are often compromised by poor accuracy and contouring *** condition is most critical as users begin to use 3D-printed components in load-bearing applications or to perform mechanical *** methods of low-cost 3D printer calibration are needed before their open-design potential can be realized in applications,including 3D-printed orthotics and *** paper applies methodologies associated with high-precision cNc machining systems,namely,kinematic error modeling and compensation coupled with standardized test methods from ISO230-4,such as the ballbar for kinematic and dynamic error measurements,to examine the influence and feasibility for use on low-cost cNc/3D printing ***,the *** and Drug Administration's"Technical considerations for additive manufactured medical devices"highlighted the need to develop standards specific to additive manufacturing in regulated manufacturing *** paper shows the benefits of the methods described within ISO230-4 for error assessment,alongside applying kinematic error modeling and compensation to the popular kinematic configuration of an Ultimaker 3D printer.A Renishaw ballbar Qc10 is used to quantify the Ultimaker's errors and thereby populate the error *** method quantifies machine errors and populates these in a mathematical model of the cNc ***,a post-processor can be used to compensate the printing ***,the ballbar is used to demonstrate the dramatic impact of the error compensation model on the accuracy and contouring of the Ultimaker pr

关键词： 3D printing accuracy Kinematic error modeling Kinematic error compensation Ballbar FDM3D printing ISO230-4

Effect of Skin on Finite Element Modeling of Foot and Ankle During Balanced Standing

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Journal of Shanghai Jiaotong university(Science) 2018年第1期23卷 132-137页

作者：欧海华 QAISER Zeeshan 康利平 JOHNSON shane University of Michigan-Shanghai Jiao Tong University Joint Institute State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Experimental measurements of stresses and strains for lower extremity injuries(LEI) are invasive, and therefore, predictions require physiologically accurate 3D finite element(FE) models of the foot and ankle. In previous models, skin is typically neglected. However, experimental studies have shown that skin is much stiffer than soft tissue. In this study, the material sensitivity of skin on foot arch deformation is investigated. A finite element model of the foot is developed, incorporating bones, soft tissue, ligament, articulating surfaces, plantar aponeurosis, skin and plantar plate. Balanced standing is simulated without skin or with three different skin mechanical properties. By including different skin models, the foot static vertical stiffness, navicular displacement and plantar aponeurosis strain change significantly, when compared with the model without skin. The study shows that skin, showing a much stiffer behaviour than soft tissue, should not be neglected in the foot modelling. Further,the plantar plate considered in this model can give merit to modelling injuries such as plantar plate tearing.

关键词： finite element analysis foot and ankle hyperelastic material plantar plate

Effect of body mass index on functional outcome in primary total knee arthroplasty——a single institution analysis of 2180 primary total knee replacements

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World Journal of Orthopedics 2016年第10期7卷 664-669页

作者： shane c O'Neill Joseph S Butler Adam Daly Darren F Lui Patrick Kenny Department of Orthopaedics Cappagh National Orthopaedic Hospital

AIM To evaluate the effect of body mass index(BMI) on short-term functional outcome and complications in primary total knee arthroplasty. METHODS All patients undergoing primary total knee arthroplasty at a single institution between 2007 and 2013 were identified from a prospective arthroplasty database. 2180 patients were included in the study. Age, gender, BMI, pre- and post-operative functional scores [Western Ontario and Mc Master University Arthritis Index(WOMAc) and SF-36], complications and revision rate were recorded. Patients were grouped according to the WHO BMI classification. The functional outcome of the normal weight cohort(BMI compared to the overweight and obese(BMI ≥ 25) cohort. A separate sub-group analysis was performed comparing all five WHO BMI groups; Normal weight, overweight, class 1 obese, class 2 obese and class 3 *** With a mean age of 67.89(28-92), 2180 primary total knee replacements were included. 64.36%(1403) were female. The mean BMI was 31.86(18-52). Ninty-three percent of patients were either overweight or obese. Mean follow-up 19.33 mo(6-60 mo). There was no significant difference in pre or post-operative WOMAc score in the normal weight(BMI cohort compared to patients with a BMI ≥ 25(P > 0.05). Sub-group analysis revealed significantly worse WOMAc scores in class 2 obese 30.80 compared to overweight 25.80(P class 1 obese 25.50(P cantly worse SF-36 scores in class 2 obese 58.16 compared to overweight 63.93(P class 1 obese 63.65(P cial infections, 9(0.41%) deep infections and 19(0.87%) revisions overall with no complications or revisions in the normal weight cohort(BMI cONcLUSION Post-operative functional outcome was not influenced by BMI comparing normal weight individuals with BMI > 25. Patients should not be denied total knee arthroplasty based solely on weight alone.

关键词： Total knee replacement Body mass index Total knee arthroplasty

characterization of multi-scale ionospheric irregularities using ground-based and space-based GNSS observations

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Satellite Navigation 2021年第1期2卷 192-212页

作者： YuXiang Peng Wayne A Scales Michael D Hartinger Zhonghua Xu shane coyle center for Space Science and Engineering Research Virginia TechBlacksburgVA 24061USA Bradley Department of Electrical and computer Engineering Virginia TechBlacksburgVA 24061USA Space Science Institute BoulderCO 80301USA National Institute of Aerospace HamptonVA 23666USA center for Space Science and Engineering Research Virginia TechBlacksburgVA 24061USA.

Ionospheric irregularities can adversely affect the performance of Global Navigation Satellite System (GNSS). How-ever, this opens the possibility of using GNSS as an effective ionospheric remote sensing tool. Despite ionospheric monitoring has been undertaken for decades, these irregularities in multiple spatial and temporal scales are still not fully understood. This paper reviews Virginia Tech’s recent studies on multi-scale ionospheric irregularities using ground-based and space-based GNSS observations. First, the relevant background of ionospheric irregularities and their impact on GNSS signals is reviewed. Next, three topics of ground-based observations of ionospheric irregulari-ties for which GNSS and other ground-based techniques are used simultaneously are reviewed. Both passive and active measurements in high-latitude regions are covered. Modelling and observations in mid-latitude regions are considered as well. Emphasis is placed on the increased capability of assessing the multi-scale nature of ionospheric irregularities using other traditional techniques (e.g., radar, magnetometer, high frequency receivers) as well as GNSS observations (e.g., Total-Electron-content or TEc, scintillation). Besides ground-based observations, recent advances in GNSS space-based ionospheric measurements are briefly reviewed. Finally, a new space-based ionospheric observa-tion technique using GNSS-based spacecraft formation flying and a differential TEc method is demonstrated using the newly developed Virginia Tech Formation Flying Testbed (VTFFTB). Based on multi-constellation multi-band GNSS, the VTFFTB has been developed into a hardware-in-the-loop simulation testbed with external high-fidelity global ionospheric model(s) for 3-satellite formation flying, which can potentially be used for new multi-scale ionospheric measurement mission design.

关键词： GNSS Ionospheric irregularities Remote sensing Active experiment Spacecraft formation flying

ANAGRAM PROBLEM-SOLVING AND LEARNING IN ANTERIOR PREFRONTAL cORTEX

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Journal of Innovative Optical Health Sciences 2008年第2期1卷 157-175页

作者： SHOKO NIOKA JOSEPH I.TRAcY shane RAINES ScOTT BUNcE BRITTON cHANcE Department of Biochemistry-Biophysics Biostatistics University of PennsylvaniaPAUSA Department of Neurology and Radiology Thomas Jefferson University§Department of PsychologyDrexel University PhiladelphiaPAUSA

We utilized Near-Infrared(NIR)spectroscopy to closely investigate the activation change in anterior prefrontal cortex(aPFc)during verbal anagram problem-solving and *** used a parametric design of anagram-solving with three difficulty levels and evaluated anagram skill with two sets of subjects and *** first protocol was a one-time evaluation of untrained subjects(n=10)and the second protocol evaluated subjects over 6 weeks of training(n=6).The untrained subjects in the first protocol demonstrated blood oxygenation corresponding to neuronal activation in the aPFc in response to medium and hard difficulty levels of the stimuli,while the easy anagram task deoxygenated the aPFc bilaterally,corresponding to *** performers have more aPFc activation than lower performers in the medium difficulty level anagram-solving *** weeks of training in the second protocol showed that training reduced oxygenation in *** particular,subjects with lower baseline skill in anagram production showed a larger reduction in oxygenation where true performance gains occurred(medium difficulty)and smaller reduction where the performance gains were limited(hard anagrams).Association of the aPFc activation with the difficulty of the complex task suggests that aPFc is a part of a circuit for execution of task *** addition,more use of aPFc by untrained high performers suggests that the role of the aPFc is to increase efficiency of a problem-solving ***,the NIR spectroscopy showed that the aPFc is a key structure in the circuit implementing the development of anagram skill.

关键词： Anagram anterior prefrontal cortex hemoglobin NIR oxygenation training effects difficulty

Is it necessary to fuse to the pelvis when correcting scoliosis in cerebral palsy?

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World Journal of Orthopedics 2022年第4期13卷 365-372页

作者： shane F Strom Matthew c Hess Achraf H Jardaly Michael J conklin Shawn R Gilbert Department of Orthopaedics University of Alabama at BirminghamBirminghamAl 35294United States Department of Orthopaedics The Hughston Clinic/Hughston FoundationColumbusGA 31908United States

BAcKGROUND Neuromuscular scoliosis is commonly associated with a large pelvic *** in children with cerebral palsy is most commonly managed with posterior spinal instrumentation and *** consensus is reached regarding the proximal starting point of fusion,controversy exists as to whether the distal level of spinal fusion should include the pelvis to correct the pelvic *** To assess the role of pelvic fusion in posterior spinal instrumentation and fusion,particularly it impact on pelvic obliquity correction,and to assess if the rate of complications differed as a function of pelvic *** This was a retrospective,cohort study in which we reviewed the medical records of children with cerebral palsy scoliosis treated with posterior instrumentation and fusion at a single *** follow-up was six *** were stratified into two groups:Those who were fused to the pelvis and those fused to L4/*** major outcomes were complications and radiographic *** former were stratified into major and minor complications,and the latter consisted of preoperative and final cobb angles,L5-S1 tilt and pelvic *** The study included 47 *** correction of the L5 tilt was 60%in patients fused to the pelvis and 67%in patients fused to L4/L5(P=0.22).The pelvic obliquity was corrected by 43%and 36%in each group,respectively(P=0.12).Regarding complications,patients fused to the pelvis had more total complications as compared to the other group(63.0%vs 30%,respectively,P=0.025).After adjusting for differences in radiographic parameters(lumbar curve,L5 tilt,and pelvic obliquity),these patients had a 79%increased chance of developing complications(Relative risk=1.79;95%cI:1.011-3.41).cONcLUSION Including the pelvis in the distal level of fusion for cerebral palsy scoliosis places patients at an increased risk of postoperative *** added value that pelvic fusion offers in terms of correcting

关键词： cerebral palsy Scoliosis Pelvic fusion Pelvic obliquity Spinal fusion Distal lumbar level

Evaluating the Impacts of Using Different Digital Surface Models to Estimate Forest Height with TanDEM-X Interferometric coherence Data

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雷达学报（中英文） 2020年第2期9卷 386-398页

作者： cHEN Hao HILL David A. WHITE Joanne c. cLOUDE shane R. canadian Forest Service 506 Burnside Road WestVictoriaBritish ColumbiaV8Z 1M5Canada Applied Electromagnetics consultants 26 Westfield AvenueCuparFifeKY155AAUK

In our previous studies, we demonstrated the usefulness of TanDEM-X interferometric bistatic mode with single polarization to obtain forest heights for the purposes of large area mapping. A key feature of our approach has been the use of a simplified Random Volume Over Ground(RVOG) model that locally estimates forest height. The model takes TanDEM-X interferometric coherence amplitude as an input and uses an external Digital Surface Model(DSM) to account for local slope variations due to terrain topography in order to achieve accurate forest height estimation. The selection of DSM for use as a local slope reference is essential, as an inaccurate DSM will result in less accurate terrain-correction and forest height estimation. In this paper, we assessed TanDEM-X height estimates associated with scale variations in different DSMs used in the model over a remote sensing supersite in Petawawa, canada. The DSMs used for assessments and comparisons included ASTER GDEM, ALOS GDSM, airborne DRAPE DSM, canadian DSM and TanDEM-X DSM. Airborne Laser Scanning(ALS) data were used as reference for terrain slope and forest height comparisons. The results showed that, with the exception of the ASTER GDEM, all DSMs were sufficiently accurate for the simplified RVOG model to provide a satisfactory estimate of stand-level forest height. When compared to the ALS 95th height percentile, the modeled forest heights had R2 values greater than 80% and Root-Mean-Square Errors(RMSE)less than 2 m. For a close similarity in slope estimation with the ALS reference, coverage across canada and open data access, the 0.75 arc-second(20 m) resolution canadian DSM was selected as a preferred choice for the simplified RVOG model to provide TanDEM-X height estimation in canada.

关键词： Interferometric cOA Digital surface model Forest height