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Full-Text Articles in Engineering

Development Of The New Educational Content "Small Uas In Civil Engineering Application Scenarios", E. Levin, K. Vach, R. Shults Dec 2017

Development Of The New Educational Content "Small Uas In Civil Engineering Application Scenarios", E. Levin, K. Vach, R. Shults

Michigan Tech Publications

The key point of this paper is presentation of the main idea and some results of the project "Small UAS in civil engineering application scenarios" (SUAS-CAS). This project was proposed by newly established in 2016 ISPRS WG V/7: "Innovative Technologies in Training Civil Engineers and Architects". Here we are presenting our experience in using low-cost UAS in training architects at Kyiv National University of Construction and Architecture, which was chosen as basic for this project. In the first part of paper, the project outline is presented. Then the first and possible follow project outcomes were described. In some details is …


Wearete: A Scalable Wearable E-Textile Triboelectric Energy Harvesting System For Human Motion Scavenging, Xian Li, Ye Sun Nov 2017

Wearete: A Scalable Wearable E-Textile Triboelectric Energy Harvesting System For Human Motion Scavenging, Xian Li, Ye Sun

Michigan Tech Publications

In this paper, we report the design, experimental validation and application of a scalable, wearable e-textile triboelectric energy harvesting (WearETE) system for scavenging energy from activities of daily living. The WearETE system features ultra-low-cost material and manufacturing methods, high accessibility, and high feasibility for powering wearable sensors and electronics. The foam and e-textile are used as the two active tribomaterials for energy harvester design with the consideration of flexibility and wearability. A calibration platform is also developed to quantify the input mechanical power and power efficiency. The performance of the WearETE system for human motion scavenging is validated and calibrated …


Preparation And Properties Of Asphalt Binders Modified By Thfs Extracted From Direct Coal Liquefaction Residue, Jie Ji, Hui Yao, Wenhua Zheng, Zhi Suo, Yuefeng Shi, Ying Xu, Hao Wu, Zhanping You Nov 2017

Preparation And Properties Of Asphalt Binders Modified By Thfs Extracted From Direct Coal Liquefaction Residue, Jie Ji, Hui Yao, Wenhua Zheng, Zhi Suo, Yuefeng Shi, Ying Xu, Hao Wu, Zhanping You

Michigan Tech Publications

This paper aims to study the preparation and viscoelastic properties of asphalt binder modified by tetrahydrofuran soluble fraction (THFS) extracted from direct coal liquefaction residue. The modified asphalt binders, which blended with SK-90 (control asphalt binder) and 4%, 6%, 8% and 10% THFS (by weight of SK-90), were fabricated. The preparation process for asphalt binder was optimized in terms of the orthogonal array test strategy and gray correlation analysis results. The properties of asphalt binder were measured by applying Penetration performance grade and Superpave performance grade specifications. In addition, the temperature step and frequency sweep test in Dynamic Shear Rheometer …


Early Warning System For Shallow Landslides Using Rainfall Threshold And Slope Stability Analysis, Shruti Naidu, K. S. Sajinkumar, Thomas Oommen, V.J. Anuja, Rinu Samuel, C. Muraleedharan Oct 2017

Early Warning System For Shallow Landslides Using Rainfall Threshold And Slope Stability Analysis, Shruti Naidu, K. S. Sajinkumar, Thomas Oommen, V.J. Anuja, Rinu Samuel, C. Muraleedharan

Michigan Tech Publications

A combined cluster and regression analysis were performed for the first time to identify rainfall threshold that triggers landslide events in Amboori, Kerala, India. Amboori is a tropical area that is highly vulnerable to landslides. The 2, 3, and 5-day antecedent rainfall data versus daily rainfall was clustered to identify a cluster of critical events that could potentially trigger landslides. Further, the cluster of critical events was utilized for regression analysis to develop the threshold equations. The 5-day antecedent (x-variable) vs. daily rainfall (y-variable) provided the best fit to the data with a threshold equation of …


Evaluation Of Five Dry Particle Deposition Parameterizations For Incorporation Into Atmospheric Transport Models, Tanvir Khan, Judith Perlinger Oct 2017

Evaluation Of Five Dry Particle Deposition Parameterizations For Incorporation Into Atmospheric Transport Models, Tanvir Khan, Judith Perlinger

Michigan Tech Publications

Despite considerable effort to develop mechanistic dry particle deposition parameterizations for atmospheric transport models, current knowledge has been inadequate to propose quantitative measures of the relative performance of available parameterizations. In this study, we evaluated the performance of five dry particle deposition parameterizations developed by Zhang et al. (2001) ("Z01"), Petroff and Zhang (2010) ("PZ10"), Kouznetsov and Sofiev (2012) ("KS12"), Zhang and He (2014) ("ZH14"), and Zhang and Shao (2014) ("ZS14"), respectively. The evaluation was performed in three dimensions: model ability to reproduce observed deposition velocities, Vd (accuracy); the influence of imprecision in input parameter values on the modeled Vd …


All-Dielectric Metamaterials: Irrelevance Of Negative Refraction To Overlapped Mie Resonances, Navid Gandji, George Semouchkin, Elena Semouchkina Oct 2017

All-Dielectric Metamaterials: Irrelevance Of Negative Refraction To Overlapped Mie Resonances, Navid Gandji, George Semouchkin, Elena Semouchkina

Michigan Tech Publications

All-dielectric metamaterials comprised of identical resonators draw a lot of attention as low-loss media providing for negative refraction, which is commonly attributed to the double negativity of effective material parameters caused by overlapping of Mie resonances. We study dispersion diagrams of such metamaterials composed of dielectric rod arrays and show that bandwidths of positive and negative refraction and its type are irrelevant to the negativity of effective parameters; instead, they are unambiguously defined by the shape and the location of the second transmission branch in dispersion diagrams and thus can be controlled by the lattice constants.


Towards An Alternate Evaluation Of Moisture-Induced Damage Of Bituminous Materials, Aboelkasim Diab, Zhanping You, Xu Yang, Mohd Rosli Mohd Hasan Oct 2017

Towards An Alternate Evaluation Of Moisture-Induced Damage Of Bituminous Materials, Aboelkasim Diab, Zhanping You, Xu Yang, Mohd Rosli Mohd Hasan

Michigan Tech Publications

Moisture-induced damage is widely known to cause multiple distresses that affect the durability of constructed pavements and eventually lead to the costly maintenance of pavement structures. The reliability and practicality of the assessment protocol to evaluate moisture susceptibility of flexible pavements presents a dilemma within the asphalt community that arises from the complexity and interrelation of moisture mechanisms in the asphalt–aggregate system. Researchers worldwide are continuously trying to develop suitable evaluation methods to simulate the combined destructive field-induced effects of moisture in the laboratory to help practitioners identify and alleviate this complex problem. The main objective of this article is …


The Prospects Of Zinc As A Structural Material For Biodegradable Implants—A Review Paper, Galit Katarivas Levy, Jeremy Goldman, Eli Aghion Oct 2017

The Prospects Of Zinc As A Structural Material For Biodegradable Implants—A Review Paper, Galit Katarivas Levy, Jeremy Goldman, Eli Aghion

Michigan Tech Publications

In the last decade, iron and magnesium, both pure and alloyed, have been extensively studied as potential biodegradable metals for medical applications. However, broad experience with these material systems has uncovered critical limitations in terms of their suitability for clinical applications. Recently, zinc and zinc-based alloys have been proposed as new additions to the list of degradable metals and as promising alternatives to magnesium and iron. The main byproduct of zinc metal corrosion, Zn2+, is highly regulated within physiological systems and plays a critical role in numerous fundamental cellular processes. Zn2+ released from an implant may suppress …


Rarefication Effects On Jet Impingement Loads, Shiying Cai, Chunpei Cai, Kai Zhang, Jun Li Sep 2017

Rarefication Effects On Jet Impingement Loads, Shiying Cai, Chunpei Cai, Kai Zhang, Jun Li

Michigan Tech Publications

Rarefication effects on jet impingement loads are studied by comparing recent new formulas at the collisionless flow limit and numerical simulations. The jet exit size is finite, and can be either planar or round. In the simulations, the jets have different degrees of rarefication, with a Knudsen (Kn) number ranging from 0 to infinity; i.e., the jet flows can be continuum, collisional, or collisionless. The comparison results indicate that (1) the new surface load formulas are accurate at the collisionless flow limit; (2) in general, the formulas offer upper limits for the peak loads; (3) however, it is improper to …


Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption, Fred Prata, Mark Woodhouse, Herbert E. Huppert, Andrew Prata, Thor Thordarson, S. Carn Sep 2017

Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption, Fred Prata, Mark Woodhouse, Herbert E. Huppert, Andrew Prata, Thor Thordarson, S. Carn

Michigan Tech Publications

The separation of volcanic ash and sulfur dioxide (SO2) gas is sometimes observed during volcanic eruptions. The exact conditions under which separation occurs are not fully understood but the phenomenon is of importance because of the effects volcanic emissions have on aviation, on the environment, and on the earth's radiation balance. The eruption of Grímsvötn, a subglacial volcano under the Vatnajökull glacier in Iceland during 21-28 May 2011 produced one of the most spectacular examples of ash and SO2 separation, which led to errors in the forecasting of ash in the atmosphere over northern Europe. Satellite data from several sources …


Cross-Correlation-Based Structural System Identification Using Unmanned Aerial Vehicles., Hyungchul Yoon, Vedhus Hoskere, Jong-Woong Park, Billie F. Spencer Sep 2017

Cross-Correlation-Based Structural System Identification Using Unmanned Aerial Vehicles., Hyungchul Yoon, Vedhus Hoskere, Jong-Woong Park, Billie F. Spencer

Michigan Tech Publications

Computer vision techniques have been employed to characterize dynamic properties of structures, as well as to capture structural motion for system identification purposes. All of these methods leverage image-processing techniques using a stationary camera. This requirement makes finding an effective location for camera installation difficult, because civil infrastructure (i.e., bridges, buildings, etc.) are often difficult to access, being constructed over rivers, roads, or other obstacles. This paper seeks to use video from Unmanned Aerial Vehicles (UAVs) to address this problem. As opposed to the traditional way of using stationary cameras, the use of UAVs brings the issue of the camera …


A Novel Applications Of Photogrammetry For Retaining Wall Assessment, Renee Oats, Rudiger Escobar-Wolf, Thomas Oommen Aug 2017

A Novel Applications Of Photogrammetry For Retaining Wall Assessment, Renee Oats, Rudiger Escobar-Wolf, Thomas Oommen

Michigan Tech Publications

Retaining walls are critical geotechnical assets and their performance needs to be monitored in accordance to transportation asset management principles. Current practices for retaining wall monitoring consist mostly of qualitative approaches that provide limited engineering information or the methods include traditional geodetic surveying, which may provide high accuracy and reliability, but is costly and time-consuming. This study focuses on evaluating failure modes of a 2.43 m × 2.43 m retaining wall model using three-dimensional (3D) photogrammetry as a cost-effective quantitative alternative for retaining wall monitoring. As a remote sensing technique, photogrammetry integrates images collected from a camera and creates a …


Effect Of Label Noise On The Machine-Learned Classification Of Earthquake Damage, Jared Frank, Umaa Rebbapragada, James Bialas, Thomas Oommen, Timothy C. Havens Aug 2017

Effect Of Label Noise On The Machine-Learned Classification Of Earthquake Damage, Jared Frank, Umaa Rebbapragada, James Bialas, Thomas Oommen, Timothy C. Havens

Michigan Tech Publications

Automated classification of earthquake damage in remotely-sensed imagery using machine learning techniques depends on training data, or data examples that are labeled correctly by a human expert as containing damage or not. Mislabeled training data are a major source of classifier error due to the use of imprecise digital labeling tools and crowdsourced volunteers who are not adequately trained on or invested in the task. The spatial nature of remote sensing classification leads to the consistent mislabeling of classes that occur in close proximity to rubble, which is a major byproduct of earthquake damage in urban areas. In this study, …


Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset, Colleen B. Mouw, Audrey B. Ciochetto, Brice Grunert, Angela W. Yu Jul 2017

Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset, Colleen B. Mouw, Audrey B. Ciochetto, Brice Grunert, Angela W. Yu

Michigan Tech Publications

Lake Superior is one of the largest freshwater lakes on our planet, but few optical observations have been made to allow for the development and validation of visible spectral satellite remote sensing products. The dataset described here focuses on coincidently observing inherent and apparent optical properties along with biogeochemical parameters. Specifically, we observe remote sensing reflectance, absorption, scattering, backscattering, attenuation, chlorophyll concentration, and suspended particulate matter over the ice-free months of 2013-2016. The dataset substantially increases the optical knowledge of the lake. In addition to visible spectral satellite algorithm development, the dataset is valuable for characterizing the variable light field, …


Novel Durable Antimicrobial Ceramic With Embedded Copper Sub-Microparticles For A Steady-State Release Of Copper Ions, Adam J. Drelich, Jessie Miller, Robert Donofrio, Jaroslaw Drelich Jul 2017

Novel Durable Antimicrobial Ceramic With Embedded Copper Sub-Microparticles For A Steady-State Release Of Copper Ions, Adam J. Drelich, Jessie Miller, Robert Donofrio, Jaroslaw Drelich

Michigan Tech Publications

Using pottery clay, porous ceramic stones were molded and then decorated with copper sub-microparticles inside the pores. Copper added antimicrobial functionality to the clay-based ceramic and showed ability in disinfecting water. Populations of both Staphylococcus aureus and Klebsiella pneumoniae in contaminated water were reduced by >99.9% in 3 h when exposed to an antimicrobial stone. This antimicrobial performance is attributed to a slow release of copper into water at both room and elevated temperatures. Copper is leached by water to produce ion concentrations in water at a level of 0.05–0.20 ppm after 24 to 72 h immersion tests. This concentration …


Harmonic Distortion Minimization In Power Grids With Wind And Electric Vehicles, Ritam Misra, Sumit Paudyal, Oguzhan Ceylan, Paras Mandal Jul 2017

Harmonic Distortion Minimization In Power Grids With Wind And Electric Vehicles, Ritam Misra, Sumit Paudyal, Oguzhan Ceylan, Paras Mandal

Michigan Tech Publications

Power-electronic interfacing based devices such as wind generators (WGs) and electrical vehicles (EVs) cause harmonic distortions on the power grid. Higher penetration and uncoordinated operation of WGs and EVs can lead to voltage and current harmonic distortions, which may exceed IEEE limits. It is interesting to note that WGs and EVs have some common harmonic profiles. Therefore, when EVs are connected to the grid, the harmonic pollution EVs impart onto the grid can be reduced to some extent by the amount of wind power injecting into the grid and vice versa. In this context, this work studies the impact of …


Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates, Norbert Pirk, Jakob Sievers, Jordan Mertes, Frans Jan W. Parmentier, Mikhail Mastepanov, Torben R. Christensen Jun 2017

Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates, Norbert Pirk, Jakob Sievers, Jordan Mertes, Frans Jan W. Parmentier, Mikhail Mastepanov, Torben R. Christensen

Michigan Tech Publications

The large spatial variability in Arctic tundra complicates the representative assessment of CO2 budgets. Accurate measurements of these heterogeneous landscapes are, however, essential to understanding their vulnerability to climate change. We surveyed a polygonal tundra lowland on Svalbard with an unmanned aerial vehicle (UAV) that mapped ice-wedge morphology to complement eddy covariance (EC) flux measurements of CO2. The analysis of spectral distributions showed that conventional EC methods do not accurately capture the turbulent CO2 exchange with a spatially heterogeneous surface that typically features small flux magnitudes. Nonlocal (low-frequency) flux contributions were especially pronounced during snowmelt and introduced a large bias …


Effects Of Short Term Hypoxia-Preconditioning On Glial Phenotype Induction Of Human Mesenchymal Stem Cells, Zichen Qian, Qi Xing, Corey Fase, Kyle Jansen, Feng Zhao Jun 2017

Effects Of Short Term Hypoxia-Preconditioning On Glial Phenotype Induction Of Human Mesenchymal Stem Cells, Zichen Qian, Qi Xing, Corey Fase, Kyle Jansen, Feng Zhao

Michigan Tech Publications

Development of successful clinical treatments for peripheral nerve injury is limited due to the complications behind neural physiology. Human mesenchymal stem cells (hMSCs) have the ability to directly promote tissue repair and protect cells at the injury site. Studies have shown that hMSCs can be transplanted to improve nerve regeneration. Hypoxic culture condition has been proven to maintain the stemness of hMSCs for later differentiation. In this study, we investigated the effects of low oxygen (O2) (2% and 5% O2) pre-treatment and initial seeding density (500, 1000, and 2000 cells/cm2) on glial protein expression …


Off-Line Handwritten Signature Recognition By Wavelet Entropy And Neural Network, Khaled Daqrouq, Husam Sweidan, Ahmad Balamesh, Mohammed N. Ajour May 2017

Off-Line Handwritten Signature Recognition By Wavelet Entropy And Neural Network, Khaled Daqrouq, Husam Sweidan, Ahmad Balamesh, Mohammed N. Ajour

Michigan Tech Publications

Handwritten signatures are widely utilized as a form of personal recognition. However, they have the unfortunate shortcoming of being easily abused by those who would fake the identification or intent of an individual which might be very harmful. Therefore, the need for an automatic signature recognition system is crucial. In this paper, a signature recognition approach based on a probabilistic neural network (PNN) and wavelet transform average framing entropy (AFE) is proposed. The system was tested with a wavelet packet (WP) entropy denoted as a WP entropy neural network system (WPENN) and with a discrete wavelet transform (DWT) entropy denoted …


Analysis Of Preparation And Properties On Shape Memory Hydrogenated Epoxy Resin Used For Asphalt Mixtures, Biao Ma, Xueyan Zhou, Kun Wei, Yanzhen Bo, Zhanping You May 2017

Analysis Of Preparation And Properties On Shape Memory Hydrogenated Epoxy Resin Used For Asphalt Mixtures, Biao Ma, Xueyan Zhou, Kun Wei, Yanzhen Bo, Zhanping You

Michigan Tech Publications

The objective of this investigation is to prepare the shape memory hydrogenated epoxy resin used for asphalt mixtures (SM-HEP-AM) and study its properties. The shape memory hydrogenated epoxy resin (SM-HEP) is prepared using hydrogenated bisphenol A epoxy resin (AL-3040), polypropylene glycol diglycidylether diacrylate (JH-230), and isophorone diamine (IPDA). The formulations of the SM-HEP-AM are obtained by the linearly fitted method. The thermo-mechanical property, molecular structure, and shape-memory performance of the SM-HEP-AM are studied. The glass-transition temperature (Tg) is determined using the differential scanning calorimeter (DSC). The results proved that the Tg level increased when the JH-230 content …


Gradient-Enriched Finite Element Methodology For Axisymmetric Problems, C. Bagni, H. Askes, E. C. Aifantis Apr 2017

Gradient-Enriched Finite Element Methodology For Axisymmetric Problems, C. Bagni, H. Askes, E. C. Aifantis

Michigan Tech Publications

Due to the axisymmetric nature of many engineering problems, bi-dimensional axisymmetric finite elements play an important role in the numerical analysis of structures, as well as advanced technology micro/nano-components and devices (nano-tubes, nano-wires, micro-/nano-pillars, micro-electrodes). In this paper, a straightforward C0-continuous gradient-enriched finite element methodology is proposed for the solution of axisymmetric geometries, including both axisymmetric and non-axisymmetric loads. Considerations about the best integration rules and an exhaustive convergence study are also provided along with guidances on optimal element size. Moreover, by applying the present methodology to cylindrical bars characterised by a circumferential sharp crack, the ability of the present …


An Improved Electron Pre-Sheath Model For Tss-1r Current Enhancement Computations, Chunpei Cai Mar 2017

An Improved Electron Pre-Sheath Model For Tss-1r Current Enhancement Computations, Chunpei Cai

Michigan Tech Publications

This report presents improvements of investigations on the Tethered Satellite System (TSS)-1R electron current enhancement due to magnetic limited collections. New analytical expressions are obtained for the potential and temperature changes across the pre-sheath. The mathematical treatments in this work are more rigorous than one past approach. More experimental measurements collected in the ionosphere during the TSS-1R mission are adopted for validations. The relations developed in this work offer two bounding curves for these data points quite successfully; the average of these two curves is close to the curve-fitting results for the measurements; and an average of 2.95 times larger …


The Influence Of Bmss On The Characterization And Modeling Of Series And Parallel Li-Ion Packs, Sandra Castano-Solis, Daniel Serrano-Jimenez, Lucia Gauchia, Javier Sanz Feb 2017

The Influence Of Bmss On The Characterization And Modeling Of Series And Parallel Li-Ion Packs, Sandra Castano-Solis, Daniel Serrano-Jimenez, Lucia Gauchia, Javier Sanz

Michigan Tech Publications

This work analyzes the effects of a BMS (battery management system) on the characterization and modeling of series and parallel connections of Li-ion cell packs. The Li-ion pack studied consists of four series modules connected in parallel. This pack has been characterized by means of charge, discharge and frequency tests. As a result of these tests, series and parallel influence on battery parameters have been determined. A model considering the effects of a BMS is established and compared with a model based on a single-cell approach. Experimental validations show that the single cell based approach gives poor results in comparison …


Adhesion Evaluation Of Asphalt-Aggregate Interface Using Surface Free Energy Method, Jie Ji, Hui Yao, Luhou Liu, Zhi Suo, Peng Zhai, Xu Yang, Zhanping You Feb 2017

Adhesion Evaluation Of Asphalt-Aggregate Interface Using Surface Free Energy Method, Jie Ji, Hui Yao, Luhou Liu, Zhi Suo, Peng Zhai, Xu Yang, Zhanping You

Michigan Tech Publications

The influence of organic additives (Sasobit and RH) and water on the adhesion of the asphalt-aggregate interface was studied according to the surface free energy theory. Two asphalt binders (SK-70 and SK-90), and two aggregate types (limestone and basalt) were used in this study. The sessile drop method was employed to test surface free energy components of asphalt, organic additives and aggregates. The adhesion models of the asphalt-aggregate interface in dry and wet conditions were established, and the adhesion work was calculated subsequently. The energy ratios were built to evaluate the effect of organic additives and water on the adhesiveness …


New-Generation Nasa Aura Ozone Monitoring Instrument (Omi) Volcanic So2 Dataset: Algorithm Description, Initial Results, And Continuation With The Suomi-Npp Ozone Mapping And Profiler Suite (Omps), Can Li, Nickolay A. Krotkov, Simon Carn, Yan Zhang, Robert J.D. Spurr, Joanna Joiner Feb 2017

New-Generation Nasa Aura Ozone Monitoring Instrument (Omi) Volcanic So2 Dataset: Algorithm Description, Initial Results, And Continuation With The Suomi-Npp Ozone Mapping And Profiler Suite (Omps), Can Li, Nickolay A. Krotkov, Simon Carn, Yan Zhang, Robert J.D. Spurr, Joanna Joiner

Michigan Tech Publications

Since the fall of 2004, the Ozone Monitoring Instrument (OMI) has been providing global monitoring of volcanic SO2 emissions, helping to understand their climate impacts and to mitigate aviation hazards. Here we introduce a new-generation OMI volcanic SO2 dataset based on a principal component analysis (PCA) retrieval technique. To reduce retrieval noise and artifacts as seen in the current operational linear fit (LF) algorithm, the new algorithm, OMSO2VOLCANO, uses characteristic features extracted directly from OMI radiances in the spectral fitting, thereby helping to minimize interferences from various geophysical processes (e.g., O3 absorption) and measurement details (e.g., wavelength shift). To solve …


Arctic Micromonas Uses Protein Pools And Non-Photochemical Quenching To Cope With Temperature Restrictions On Photosystem Ii Protein Turnover, Guangyan Ni, Gabrielle Zimbalatti, Cole D. Murphy, Audrey B. Barnett, Christopher M. Arsenault, Gang Li, Amanda M. Cockshutt, Douglas A. Campbell Feb 2017

Arctic Micromonas Uses Protein Pools And Non-Photochemical Quenching To Cope With Temperature Restrictions On Photosystem Ii Protein Turnover, Guangyan Ni, Gabrielle Zimbalatti, Cole D. Murphy, Audrey B. Barnett, Christopher M. Arsenault, Gang Li, Amanda M. Cockshutt, Douglas A. Campbell

Michigan Tech Publications

Micromonas strains of small prasinophyte green algae are found throughout the world’s oceans, exploiting widely different niches. We grew arctic and temperate strains of Micromonas and compared their susceptibilities to photoinactivation of Photosystem II, their counteracting Photosystem II repair capacities, their Photosystem II content, and their induction and relaxation of non-photochemical quenching. In the arctic strain Micromonas NCMA 2099, the cellular content of active Photosystem II represents only about 50 % of total Photosystem II protein, as a slow rate constant for clearance of PsbA protein limits instantaneous repair. In contrast, the temperate strain NCMA 1646 shows a faster clearance …


A New Gaskinetic Model To Analyze Background Flow Effects On Weak Gaseous Jet Flows From Electric Propulsion Devices, Chunpei Cai Jan 2017

A New Gaskinetic Model To Analyze Background Flow Effects On Weak Gaseous Jet Flows From Electric Propulsion Devices, Chunpei Cai

Michigan Tech Publications

Recent work on studying rarefied background and jet flow interactions is reported. A new gaskinetic method is developed to investigate two closely related problems. The first problem is how a collisionless background flow can affect a highly rarefied jet flow. The rarefied jet and background flow conditions are assumed available and described with seven parameters. Gaskinetic theories are applied and formulas are obtained for the mixture properties. Simulations are performed to validate these expressions, and excellent agreement is obtained. The second problem is to recover the collisionless background and jet flow parameters with limited measurements. A group of linearized equations …


Property Analysis Of Exfoliated Graphite Nanoplatelets Modified Asphalt Model Using Molecular Dynamics (Md) Method, Hui Yao, Qingli Dai, Zhanping You, Andreas Bick, Min Wang, Shuaicheng Guo Jan 2017

Property Analysis Of Exfoliated Graphite Nanoplatelets Modified Asphalt Model Using Molecular Dynamics (Md) Method, Hui Yao, Qingli Dai, Zhanping You, Andreas Bick, Min Wang, Shuaicheng Guo

Michigan Tech Publications

This Molecular Dynamics (MD) simulation paper presents a physical property comparison study between exfoliated graphite nanoplatelets (xGNP) modified and control asphalt models, including density, glass transition temperature, viscosity and thermal conductivity. The three-component control asphalt model consists of asphaltenes, aromatics, and saturates based on previous references. The xGNP asphalt model was built by incorporating an xGNP and control asphalt model and controlling mass ratios to represent the laboratory prepared samples. The Amber Cornell Extension Force Field (ACEFF) was used with assigned molecular electro-static potential (ESP) charge from NWChem analysis. After optimization and ensemble relaxation, the properties of the control and …


Quantitating Active Photosystem Ii Reaction Center Content From Fluorescence Induction Transients, Cole D. Murphy, Guangyan Ni, Gang Li, Audrey Barnett, Kui Xu, Jessica Grant-Burt, Justin D. Liefer, David J. Suggett, Douglas A. Campbell Jan 2017

Quantitating Active Photosystem Ii Reaction Center Content From Fluorescence Induction Transients, Cole D. Murphy, Guangyan Ni, Gang Li, Audrey Barnett, Kui Xu, Jessica Grant-Burt, Justin D. Liefer, David J. Suggett, Douglas A. Campbell

Michigan Tech Publications

Photosystem II (PSII) is a pigment-protein complex that photochemically extracts electrons from water, generating the reductant that supports biological productivity in all biomes. Estimating the content of active PSII reaction centers in a liquid sample is a key input for estimating aquatic photosynthesis rates, as well as for analyzing phytoplankton stress responses. Established procedures for PSII content quantification based on oxygen evolution are slow, imprecise and require dense cell suspensions, and are thus inapplicable to many laboratory or field studies. A new approach uses baseline chlorophyll fluorescence emission divided by the effective absorbance cross section for PSII photochemistry, with both …


Surface Ozone And Its Precursors At Summit, Greenland: Comparison Between Observations And Model Simulations, Yaoxian Huang, Shiliang Wu, Louisa J. Kramer, Detlev Helmig, Richard E. Honrath Jan 2017

Surface Ozone And Its Precursors At Summit, Greenland: Comparison Between Observations And Model Simulations, Yaoxian Huang, Shiliang Wu, Louisa J. Kramer, Detlev Helmig, Richard E. Honrath

Michigan Tech Publications

Recent studies have shown significant challenges for atmospheric models to simulate tropospheric ozone (O3/and its precursors in the Arctic. In this study, ground-based data were combined with a global 3-D chemical transport model (GEOS-Chem) to examine the abundance and seasonal variations of O3 and its precursors at Summit, Greenland (72.34° N, 38.29° W; 3212 ma.s.l.). Model simulations for atmospheric nitrogen oxides (NOx/, peroxyacetyl nitrate (PAN), ethane (C2H6/, propane (C3H8/, carbon monoxide (CO), and O3 for the period July 2008-June 2010 were compared with observations. The model performed well in simulating certain species (such as CO and C3H8/, but some significant …