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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

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Progesterone modulates m TOR in the hippocampus of mice after traumatic brain injury

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Neural Regeneration Research 2018年第3期13卷 434-439页

作者： Richard Justin Garling Lora Talley Watts shane Sprague Murat Digicaylioglu Department of Neurosurgery Wayne State University Detroit MI USA School of Medicine The University of Texas Health Science Center at San Antonio San Antonio TX USA Department of Neurosurgery The University of Texas Health Science Center at San Antonio San Antonio TX USA

Spinal cord injury results in the loss of motor and sensory pathways and spontaneous regeneration of adult mammalian spinal cord neurons is limited. Chitosan and sodium alginate have good biocompatibility, biodegradability, and are suitable to assist the recovery of damaged tissues, such as skin, bone and nerve. Chitosan scaffolds, sodium alginate scaffolds and chitosan-sodium alginate scaffolds were separately transplanted into rats with spinal cord hemisection. Basso-Beattie-Bresnahan locomotor rating scale scores and electrophysiological results showed that chitosan scaffolds promoted recovery of locomotor capacity and nerve transduction of the experimental *** days after surgery, chitosan scaffolds retained the original shape of the spinal cord. Compared with sodium alginate scaffolds- and chitosan-sodium alginate scaffolds-transplanted rats, more neurofilament-H-immunoreactive cells （regenerating nerve fibers） and less glial fibrillary acidic protein-immunoreactive cells （astrocytic scar tissue） were observed at the injury site of experimental rats in chitosan scaffold-transplanted rats. Due to the fast degradation rate of sodium alginate, sodium alginate scaffolds and composite material scaffolds did not have a supporting and bridging effect on the damaged tissue. Above all, compared with sodium alginate and composite material scaffolds, chitosan had better biocompatibility, could promote the regeneration of nerve fibers and prevent the formation of scar tissue,and as such, is more suitable to help the repair of spinal cord injury.

关键词： nerve regeneration spinal cord injury chitosan sodium alginate functional recovery scaffold neurofilament-H glial fibrillary acidic protein scar tissue locomotor capacity neural regeneration

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Signaling Product Quality by Price

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2012年第3期7卷 363-372页

作者： shane Parendo Cheng-Zhong Qin Department of Economics University of California Santa Barbara CA 93106 USA

This paper analyzes the role of price as a signal of the quality of a monopoly firm＇s new product. The quality of the goods is drawn from a continuum and is unknown to consumers. We establish a unique separating equilibrium using equilibrium characterization results for signaling games. The equilibrium price monotonically increases with quality levels and exceeds the complete-information monopoly price for all quality levels but the lowest one. However, the upward distortion decreases as the proportion of pre-informed consumers increases. These results extend both the signaling role of price and characteristics of the separating equilibrium as established in Bagwell and Riordan （1991）.

关键词： separating equilibrium price distortion signaling game

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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

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Review on Recent Developments of Fluorescent Oxygen and Carbon Dioxide Optical Fiber Sensors

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Photonic Sensors 2011年第3期1卷 234-250页

作者： Cheng-shane CHU Yu-Lung LO Ti-Wen SUNG Department of Mechamcal Engmeermg Ming Chi University of Technology Taishan District New Taipei City TaiwanChina Department of Mechanical Engineering National Cheng Kung University Tainan Taiwan China

Oxygen and carbon dioxide sensors are involved in many chemical and biochemical reactions. Consequently, considerable efforts over years have been devoted to discover and improve suitable techniques for measuring gas concentrations by optical fiber sensors. Optical gas sensors consist of a gas-sensitive dye entrapped in a matrix with a high permeability to gas. With such sensors, gas concentration is evaluated based upon the reduction in luminescence intensity caused by gas quenching of the emitting state. However, the luminescence quenching effect of oxygen is highly sensitive to temperature. Thus, a simple, low-cost plastic optical fiber sensor for dual sensing of temperature and oxygen is presented. Also, a modified Stern-Volmer model is introduced to compensate for the temperature drift while the temperature is obtained by above dual sensor. Recently, we presented highly-sensitive oxygen and dissolved oxygen sensors comprising an optical fiber coated at one end with platinum （II） meso-tetrakis（pentafluorophenyl）porphyrin （PtTFPP） and PtTFPP entrapped core-shell silica nanoparticles embedded in an n-octyltriethoxysilane（Octyl-triEOS）/tetraethylorthosilane （TEOS） composite xerogel. Also, two-dimensional gas measurement for the distribution of chemical parameters in non-homogeneous samples is developed and is of interest in medical and biological researches.

关键词： Oxygen carbon dioxide fluorescent dye optical fiber temperature effect modified Stem-Volmermodel core-shell silica nanoparticles

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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

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Adherence to treatment guidelines in the pharmacological management of chronic heart failure in an Australian population

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Journal of Geriatric Cardiology 2011年第2期8卷 88-92页

作者： Dao-Kuo Yao Le-Xin Wang shane Curran Patrick Ball Department of Cardiology Beijing Friendship Hospital Capital Medical University Beijing 100050 China School of Biomedical Sciences and Centre for Inland Health Charles Sturt University Wagga Wagga NSW2678 Australia Department of Emergency Medicine Wagga Wagga Base Hospital and Rural Clinical School University of New South Wales Wagga Wagga NSW 2650 Australia

Background To document the pharmacotherapy of chronic heart failure （CHF） and to evaluate the adherence to treatment guidelines in Australian population. Methods The pharmacological management of 677 patients （female 46.7%, 75.5 ±11.6 years） with CHF was retrospectively analyzed. Results The use of angiotensin converting enzyme （ACE） inhibitors/angiotensin receptor blockers （ARB） and β-blockers were 58.2 % and 34.7 %, respectively. Major reasons for non-use of ACE inhibitors/ARBs were hyperkalemia and elevated serum creatinine level. For patients who did not receive β-blockers, asthma and chronic obstructive pulmonary disease were the main contraindications. Treatment at or above target dosages for ACE inhibitors/ARBs and β-blockers was low for each medication （40.3% and 28.9%, respectively）. Conclusions Evidenced-based medical therapies for heart failure were under used in a rural patient population. Further studies are required to develop processes to improve the optimal use of heart failure medications.

关键词： heart failure ACE inhibitors angiotensin receptor β-blockers prognosis

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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

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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

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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

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