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Towards An Automated Tool Chain For Mpc In Multi-Zone Buildings, Filip Jorissen, Lieve Helsen Jan 2016

Towards An Automated Tool Chain For Mpc In Multi-Zone Buildings, Filip Jorissen, Lieve Helsen

International High Performance Buildings Conference

Heating Ventilation and Air Conditioning (HVAC) represents a large fraction of the world’s primary energy demand. Novel control strategies such as Model Predictive Control (MPC) aim to reduce energy use, while also improving occupant comfort. For MPC to be a viable alternative to classical Rule Based Control (RBC), it should be able to incorporate multiple emission and production systems, multiple zones, and aspects such as thermal comfort and indoor air quality (IAQ). Identifying grey-box or black-box MPC controller models for hybrid energy systems in multi-zone buildings has proven to be difficult. White-box models use physical knowledge of the system and …

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Analysis Of Indicator Diagrams Of A Water Injected Twin-Shaft Screw-Type Expander, Alexander Nikolov, Andreas Brümmer Jan 2016

Analysis Of Indicator Diagrams Of A Water Injected Twin-Shaft Screw-Type Expander, Alexander Nikolov, Andreas Brümmer

International Compressor Engineering Conference

Twin-shaft screw-type expanders offer a high potential for energy conversion in the lower and medium power range, for instance as expansion engines in Rankine cycles for exhaust heat recovery. With regard to minimizing internal leakages and lubricating moving machine parts, an auxiliary liquid or liquid working fluid can be fed to the screw expander. In this paper, indicator diagrams of a twin-shaft screw-type expander prototype designed at the Chair of Fluidics at TU Dortmund University are presented and analyzed in detail. The experimental investigations are carried out at a hot-air test rig with expander inlet manifold water injection. The time-dependant …

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Autonomous Optimization And Control For Central Plants With Energy Storage, Michael J. Wenzel, Robert D. Turney, Kirk H. Drees Jan 2016

Autonomous Optimization And Control For Central Plants With Energy Storage, Michael J. Wenzel, Robert D. Turney, Kirk H. Drees

International High Performance Buildings Conference

A model predictive control (MPC) framework is used to determine how to optimize the distribution of energy resources across a central energy facility including chillers, water heaters, and thermal energy storage; present the results to an operator; and execute the plan. The objective of this MPC framework is to minimize cost in real-time in response to both real-time energy prices and demand charges as well as allow the operator to appropriately interact with the system. Operators must be given the correct intersection points in order to build trust before they are willing to turn the tool over and put it …

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Development Of A General Numerical Methodology For Cfd Analyses In Sliding Vane Machines And Application On A Mid-Size Oil Injected Air Compressor, Giuseppe Bianchi, Sham Rane, Ahmed Kovacevic, Roberto Cipollone, Stefano Murgia, Giulio Contaldi Jan 2016

Development Of A General Numerical Methodology For Cfd Analyses In Sliding Vane Machines And Application On A Mid-Size Oil Injected Air Compressor, Giuseppe Bianchi, Sham Rane, Ahmed Kovacevic, Roberto Cipollone, Stefano Murgia, Giulio Contaldi

International Compressor Engineering Conference

The current work presents the development of a numerical methodology to investigate sliding vane rotary machines by means of advanced design tools such as the Computational Fluid Dynamics ones. Although highly limited in this topic, literature shows that the major constraint for the employment of such approaches is the deformation and motion of the rotor mesh, i.e. the computational grid related to the fluid volume between stator, rotor and blades of the positive displacement vane device. To address these issues, a novel grid generation approach is herein proposed and accomplished through a series of steps: geometrical 2D modeling of the …

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Prediction Of Air-Side Particulate Fouling Of Hvac&R Heat Exchangers, H. Inamdar, E. A. Groll, J. A. Weibel, S V. Garimella Jan 2016

Prediction Of Air-Side Particulate Fouling Of Hvac&R Heat Exchangers, H. Inamdar, E. A. Groll, J. A. Weibel, S V. Garimella

CTRC Research Publications

Air-to-refrigerant heat exchangers used in heating, ventilation, air-conditioning, and refrigeration systems routinely experience air-side fouling due to the presence of particulates in outdoor and indoor environments. The influence on the performance of the heat exchanger, in terms of heat transfer efficiency and pressure drop imposed, depends on the extent of air-side fouling. Fouling of a heat exchanger is determined by a variety of parameters such as the dimensions of the heat exchanger, physical properties of the airborne particulates, and airflow conditions over the heat exchange surfaces. A comprehensive model is developed to deterministically calculate the extent of fouling of a …

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Missing Gene Identification Using Functional Coherence Scores, Meghana Chitale, Ishita K. Khan, Daisuke Kihara Jan 2016

Missing Gene Identification Using Functional Coherence Scores, Meghana Chitale, Ishita K. Khan, Daisuke Kihara

Department of Biological Sciences Faculty Publications

Reconstructing metabolic and signaling pathways is an effective way of interpreting a genome sequence. A challenge in a pathway reconstruction is that often genes in a pathway cannot be easily found, reflecting current imperfect information of the target organism. In this work, we developed a new method for finding missing genes, which integrates multiple features, including gene expression, phylogenetic profile, and function association scores. Particularly, for considering function association between candidate genes and neighboring proteins to the target missing gene in the network, we used Co-occurrence Association Score (CAS) and PubMed Association Score (PAS), which are designed for capturing functional …

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Sparse Non-Negative Matrix Factorization For Mesh Segmentation, Tim Mcgraw, Jisun Kang, Donald Herring Jan 2016

Sparse Non-Negative Matrix Factorization For Mesh Segmentation, Tim Mcgraw, Jisun Kang, Donald Herring

Computer Graphics Technology Faculty Publications

We present a method for 3D mesh segmentation based on sparse non-negative matrix factorization (NMF). Image analysis techniques based on NMF have been shown to decompose images into semantically meaningful local features. Since the features and coefficients are represented in terms of non-negative values, the features contribute to the resulting images in an intuitive, additive fashion. Like spectral mesh segmentation, our method relies on the construction of an affinity matrix which depends on the geometric properties of the mesh. We show that segmentation based on the NMF is simpler to implement, and can result in more meaningful segmentation results than …

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Identified Research Directions For Using Manufacturing Knowledge Earlier In The Product Lifecycle, Thomas D. Hedberg Jr, Nathan W. Hartman, Phil Rosche, Kevin Fischer Jan 2016

Identified Research Directions For Using Manufacturing Knowledge Earlier In The Product Lifecycle, Thomas D. Hedberg Jr, Nathan W. Hartman, Phil Rosche, Kevin Fischer

Computer Graphics Technology Faculty Publications

Design for manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within computer-aided design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customisation on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge …

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The New Eduspace Lernwerkstatt In The Library - A Collaboration Project Between The Faculty Of Education And The Library, Ulrike Stadler-Altmann, Gerda Winkler Jan 2016

The New Eduspace Lernwerkstatt In The Library - A Collaboration Project Between The Faculty Of Education And The Library, Ulrike Stadler-Altmann, Gerda Winkler

Proceedings of the IATUL Conferences

No abstract provided.

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Designing Rich Information Experiences To Shape Learning Outcomes, Clarence Maybee, Christine Susan Bruce, Mandy Lupton, Kristen Rebmann Jan 2016

Designing Rich Information Experiences To Shape Learning Outcomes, Clarence Maybee, Christine Susan Bruce, Mandy Lupton, Kristen Rebmann

Libraries Faculty and Staff Scholarship and Research

Students in higher education typically learn to use information as part of their course of study, which is intended to support ongoing academic, personal and professional growth. Informing the development of effective information literacy education, this research uses a phenomenographic approach to investigate the experiences of a teacher and students engaged in lessons focused on exploring language and gender topics by tracing and analyzing their evolution through scholarly discourse. The findings suggest that the way learners use information influences content-focused learning outcomes, and reveal how teachers may enact lessons that enable students to learn to use information in ways that …

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E-Book Reading Practices In Different Subject Areas: An Exploratory Log Analysis, Robert S. Freeman, E. Stewart Saunders Jan 2016

E-Book Reading Practices In Different Subject Areas: An Exploratory Log Analysis, Robert S. Freeman, E. Stewart Saunders

Libraries Faculty and Staff Scholarship and Research

Print books pose inherent difficulties for researchers who want to observe users’ natural in-book reading patterns. With e-books and logs of their use it is now possible to track several aspects of users’ interactions inside e-books, including the number and duration of their sessions with an e-book and the order in which pages are viewed. This chapter reports on a study of one-year of EBL user log data from Purdue University to identify different reading patterns or ways in which users navigate within different types of e-books—authored monographs vs. edited collections--and in e-books in different subject areas. The analysis of …

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Get A Grip: A Graduate Student Research Information Portal, Program, And Plan. Presentation, Great Lakes Science Boot Camp., Nastasha E. Johnson, Dave Zwicky Jan 2016

Get A Grip: A Graduate Student Research Information Portal, Program, And Plan. Presentation, Great Lakes Science Boot Camp., Nastasha E. Johnson, Dave Zwicky

Libraries Faculty and Staff Presentations

No abstract provided.

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Effect Of Cooling Pad Installation On Indoor Airflow Distribution In A Tunnel-Ventilated Laying-Hen House, Hui Xue, Zhu Qiang, Ji-Qin Ni, Li Baoming, Shi Zhengxiang, Zhao Shumei, Wang Yu Jan 2016

Effect Of Cooling Pad Installation On Indoor Airflow Distribution In A Tunnel-Ventilated Laying-Hen House, Hui Xue, Zhu Qiang, Ji-Qin Ni, Li Baoming, Shi Zhengxiang, Zhao Shumei, Wang Yu

School of Agricultural & Biological Engineering Faculty Publications

Extra cooling pads on the sidewalls are needed for larger poultry houses using tunnel ventilation system. Preliminary study showed that the airflow velocity going through different aisles varies greatly when the extra pads are installed at the end of sidewalls, making a “[”-shape air inlet. Combined with field tests, the CFD (computational fluid dynamics) technology was used to study the uniformity of airflow distribution in a tunnel-ventilated laying-hen house. The air distribution was first monitored in a layer house to find the main reason resulting in the variations of airflows in different aisles. Then CFD simulations were carried out with …

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Numerical Simulation On Heat Transfer Performance Of Silicon Carbide/ Nitrate Composite For Solar Power Generation, Ruixin Zhou, Xiaole Chen, Yang Lu, Bei Guo Jan 2016

Numerical Simulation On Heat Transfer Performance Of Silicon Carbide/ Nitrate Composite For Solar Power Generation, Ruixin Zhou, Xiaole Chen, Yang Lu, Bei Guo

International Refrigeration and Air Conditioning Conference

KNO3 was used as the phase change material (PCM), but its thermal conductivity is too low to transfer heat between the PCM and conduction oil efficiently. In this thesis, on the basis of the previous studies (Yong Li, 2015), the solar power generation efficiency is enhanced with high temperature interval (280℃—400℃), and the new composite which are composed by the SiC honeycomb (SCH) frame and infiltrated KNO3 is simulated by using Fluent software. The results show that the new composite of the KNO3 +30%SCH suit for the requirement of the charging time and capacity in the design of the thermal …

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Nano Roughness, Tamara J. Moore Jan 2016

Nano Roughness, Tamara J. Moore

School of Engineering Education Working Papers

No abstract provided.

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Psychrometric Properties Of Humid Air From Multi-Fluid Helmholtz-Energy-Explicit Models, Ian Bell, Eric Lemmon, Allan Harvey Jan 2016

Psychrometric Properties Of Humid Air From Multi-Fluid Helmholtz-Energy-Explicit Models, Ian Bell, Eric Lemmon, Allan Harvey

International Refrigeration and Air Conditioning Conference

Psychrometric properties of humid air are widely used in the analysis and modeling of thermal systems. In this work we present a method for obtaining these properties from the multi-fluid mixture formulation of the GERG mixture model. This mixture model was originally developed to model the thermodynamics of natural gas mixtures, and now has been extended to model thermodynamic properties relevant for carbon capture and storage. The primary advantage of this formulation is that the dry air composition is not fixed, and can be adjusted to suit the application, for instance in submarines, for Martian atmospheres, etc. We present an …

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A Numerical And Experimental Study On Skin Condensers Applied To Household Refrigerators, Elias Gava Colombo, Rodolfo Da Silva Espíndola, Fernando Testoni Knabben, Claudio Melo Jan 2016

A Numerical And Experimental Study On Skin Condensers Applied To Household Refrigerators, Elias Gava Colombo, Rodolfo Da Silva Espíndola, Fernando Testoni Knabben, Claudio Melo

International Refrigeration and Air Conditioning Conference

The aim of this work is to numerically and experimentally investigate the performance characteristics of skin condensers applied to a specific household refrigerator model. To this end a mathematical model which takes into account both the heat transfer to the ambient and to the refrigerated compartments was developed. The model predicts the condenser performance from the internal and external air temperatures, geometry, mass flow rate, pressure and temperature at the heat exchanger inlet. Steady-state energy consumption tests – compressor running continuously with electric heaters being used to create artificial thermal load – were carried out in different operating conditions with …

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Coupled Thermodynamic And Cfd Approaches Applied To A Supersonic Air Ejector, Sergio Croquer, Sébastien Poncet, Nicolas Galanis Jan 2016

Coupled Thermodynamic And Cfd Approaches Applied To A Supersonic Air Ejector, Sergio Croquer, Sébastien Poncet, Nicolas Galanis

International Refrigeration and Air Conditioning Conference

This paper presents a systematic comparison of ejector performance predictions by a thermodynamic and a CFD model for different operating conditions. The thermodynamic model developed by Galanis and Sorin (2015) assumes the primary flow is always choked, and irreversibilities due to viscous dissipation are taken into account through polytropic efficiencies. The CFD model developed by Croquer et al. (2015) using the software ANSYS Fluent v15.0 has already been validated for supersonic ejectors working with R134a. A standard high Reynolds number k- ω SST turbulence model coupled with the perfect gas law is used to model the turbulent air flows. The …

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Optimization Of A Residential Air Source Heat Pump Using Heat Exchangers With Small Diameter Tubes, Mohamed Beshr, Vikrant Aute, Reinhard Radermacher Jan 2016

Optimization Of A Residential Air Source Heat Pump Using Heat Exchangers With Small Diameter Tubes, Mohamed Beshr, Vikrant Aute, Reinhard Radermacher

International Refrigeration and Air Conditioning Conference

Heat exchangers play significant role in refrigeration and air conditioning systems. Ongoing research aims to improve, or at least maintain, the system performance while reducing the size, weight and cost of the heat exchangers. This in turn leads to lower system refrigerant charge and reduced environmental impact. Using heat exchangers with small tube diameters (less than 5 mm) instead of large tube diameters has been shown to be a promising solution to meet the aforementioned goals. However, shifting towards mall tube diameters requires in-depth analysis and optimization of several heat exchanger design parameters. This paper presents a multi-objective optimization of …

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Theoretical And Experimental Analysis Of Expansion Devices For Meso-Scale Cooling Systems, João Fabio Parise De Lara, Claudio Melo, Joel Boeng Jan 2016

Theoretical And Experimental Analysis Of Expansion Devices For Meso-Scale Cooling Systems, João Fabio Parise De Lara, Claudio Melo, Joel Boeng

International Refrigeration and Air Conditioning Conference

Nowadays there is a growing interest for compact cooling systems, the so-called meso-refrigerating systems, and thus there is also a need for innovative components which could be applied in these systems. The expansion device of meso-refrigerating systems must be properly sized not only to improve the system performance but also to work properly under varying load conditions. The aim of this work is to study the expansion process of HFC-134a through two distinct expansion devices in order to get a better understanding of the fluid flow phenomena and to support the development of mathematical models. To this end an experimental …

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Frost Growth Investigation And Temperature Glide Refrigerants In A Fin-And-Tube Heat Exchanger, Elie Keryakos, Joseph Toubassy, Denis Clodic, Georges Descombes Jan 2016

Frost Growth Investigation And Temperature Glide Refrigerants In A Fin-And-Tube Heat Exchanger, Elie Keryakos, Joseph Toubassy, Denis Clodic, Georges Descombes

International Refrigeration and Air Conditioning Conference

Bio methane is produced by removing undesirable components such as water vapor, carbon dioxide and other pollutants in a biogas upgrading process. Frosting the water vapor contained in the biogas is one of the dehydration processes used in a biogas upgrading process. In order to simulate a frost layer on a cold plate, many models have been developed. These models are valid for a limited temperature range. In this study, heat and mass transfer equations were used in a numerical approach to model the frost growth and its densification on the external side of a fin-and-tube heat exchanger. The model …

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Steady State Modeling Of Advanced Vapor Compression Systems, Mohamed Beshr, Vikrant Aute, Reinhard Radermacher Jan 2016

Steady State Modeling Of Advanced Vapor Compression Systems, Mohamed Beshr, Vikrant Aute, Reinhard Radermacher

International Refrigeration and Air Conditioning Conference

The use of heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems is always increasing. This is because the HVACR systems are necessary for food production and ability to inhabit buildings that otherwise would be inhabitable. Thus, there is continued research focused on improving the efficiency and reducing the negative environmental impact of these systems. The basic vapor compression cycle (i.e., evaporator, condenser, expansion device and compressor), which is still the main underlying HVAC&R technology worldwide, has already reached its limits and researchers are investigating more creative and complex cycles to improve capacity and efficiency. This motivates the development of an …

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Experimentally Validated Model Of Transient Heat Transfer Between A Magnetocaloric Packed Particle Bed And Stagnant Interstitial Fluid, Michael Goodman Schroeder, Ellen Brehob, Michael Benedict Jan 2016

Experimentally Validated Model Of Transient Heat Transfer Between A Magnetocaloric Packed Particle Bed And Stagnant Interstitial Fluid, Michael Goodman Schroeder, Ellen Brehob, Michael Benedict

International Refrigeration and Air Conditioning Conference

Typical simulations of packed bed active magnetocaloric regenerators rely on correlations of Nusselt number as a function of Reynolds number. These models are well understood for large ranges of Reynolds number, but experimental data is lacking as Reynolds number approaches zero.  Within a typical magnetocaloric refrigeration cycle a zero velocity or dwell condition is present.  When a cycle is heat transfer rate limited, heat transferred during dwell represents a significant portion of total heat transferred for a full cycle and must be accurately represented. An experiment was performed in order to validate a basic heat transfer model between …

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Modelling Of An R-290/Poe Iso 22 Variable Speed Air Conditioner System Under Seer Conditions, Guilherme B. Ribeiro, Jader Riso Barbosa Jr. Jan 2016

Modelling Of An R-290/Poe Iso 22 Variable Speed Air Conditioner System Under Seer Conditions, Guilherme B. Ribeiro, Jader Riso Barbosa Jr.

International Refrigeration and Air Conditioning Conference

Air-conditioning applications using propane (R-290) have several environmental and thermodynamic advantages over more commonly used refrigerants, such as R-410A and R-22. This paper presents the development of a mathematical model for variable capacity air conditioning systems that use R-290/POE ISO 22 as refrigerant/lubricant. The thermodynamic performance of the refrigeration system is evaluated in terms of the SEER (Seasonal Energy Efficiency Ratio). The thermodynamic properties of the refrigerant/lubricant mixture were obtained from a departure-function approach using the Peng-Robinson equation of state. The effect of the oil on the condenser and evaporator heat transfer coefficients and pressure drops was also taken into …

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Numerical Study On The Design Of Microchannel Evaporators For Ejector Refrigeration Cycles, Neal Lawrence, Stefan Elbel Jan 2016

Numerical Study On The Design Of Microchannel Evaporators For Ejector Refrigeration Cycles, Neal Lawrence, Stefan Elbel

International Refrigeration and Air Conditioning Conference

Two-phase ejectors are devices capable of improving the performance of refrigeration and air conditioning cycles by means of expansion work recovery. Ejector studies often focus on the design and performance of the two-phase ejector and the effect it can have on the performance of the ejector cycle. However, the ejector is not the only component of the system that can have a significant influence on the performance of the ejector cycle. Recent experimental work has shown that the effect of evaporator design on ejector cycle performance can be quite significant, though there is very little research available on the relation …

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A Novice Method For Calibrating The Transient Model Of An Automotive Hvac System, Zhiyu Yang, Junye Shi, Jianmin Li, Jiangping Chen Jan 2016

A Novice Method For Calibrating The Transient Model Of An Automotive Hvac System, Zhiyu Yang, Junye Shi, Jianmin Li, Jiangping Chen

International Refrigeration and Air Conditioning Conference

A novice method for calibrating the transient model of an automotive HVAC system is presented in this paper. Transient models can be of great importance in the development process of automotive HVAC control algorithms, especially model based ones, as it saves both time and effort. However, the calibration process is usually difficult and relies heavily on experience due to the complexity of the model. A set of customized measurement tools, which consists of several wireless temperature and humidity sensors and an OBD dongle, is used to capture time series data related to the HVAC system during normal driving. Parts of …

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Understanding The Home Math Environment And Its Role In Predicting Parent Report Of Children's Math Skills, Sara Ann Hart, Colleen M. Ganley, David J. Purpura Jan 2016

Understanding The Home Math Environment And Its Role In Predicting Parent Report Of Children's Math Skills, Sara Ann Hart, Colleen M. Ganley, David J. Purpura

Department of Human Development and Family Sciences Faculty Publications

There is a growing literature concerning the role of the home math environment in children's math development. In this study, we examined the relation between these constructs by specifically addressing three goals. The first goal was to identify the measurement structure of the home math environment through a series of confirmatory factor analyses. The second goal was to examine the role of the home math environment in predicting parent report of children's math skills. The third goal was to test a series of potential alternative explanations for the relation between the home math environment and parent report of children's skills, …

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What Tutor Researchers And Their Mentors Tell Us About Undergraduate Research In The Writing Center: An Exploratory Study, Christopher Ervin Jan 2016

What Tutor Researchers And Their Mentors Tell Us About Undergraduate Research In The Writing Center: An Exploratory Study, Christopher Ervin

The Writing Center Journal

No abstract provided.

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Decisions…Decisions: Who Chooses To Use The Writing Center?, Lori Salem Jan 2016

Decisions…Decisions: Who Chooses To Use The Writing Center?, Lori Salem

The Writing Center Journal

No abstract provided.

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Laser Mobile Mapping Standards And Applications In Transportation, Steven D. Johnson, James S. Bethel, Chisaphat Supunyachotsakul, Scott Peterson Jan 2016

Laser Mobile Mapping Standards And Applications In Transportation, Steven D. Johnson, James S. Bethel, Chisaphat Supunyachotsakul, Scott Peterson

JTRP Technical Reports

This report describes the work that was done to support the development of a chapter for the INDOT Survey Manual on Mobile Mapping. The work includes experiments that were done, data that was collected, analysis that was carried out, and conclusions that were drawn about accuracy of Mobile Terrestrial Laser Scanning (MTLS) systems. The resulting Manual chapter, located in the appendix, defines standards and procedures for preparing, collecting, editing, delivering, exploiting, and archiving electronic mapping data that is created for Indiana Department of Transportation (INDOT). The purpose of the standards and procedures within this manual is to obtain statewide uniformity …

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