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Portland State University

2017

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Articles 1 - 30 of 161

Full-Text Articles in Engineering

Microstructure And Mechanical Properties Of Additive Manufacturing Titanium Alloys After Thermal Processing, Ahmet Alptug Tanrikulu Dec 2017

Microstructure And Mechanical Properties Of Additive Manufacturing Titanium Alloys After Thermal Processing, Ahmet Alptug Tanrikulu

Dissertations and Theses

Titanium alloys are widely used for aerospace and biomaterial applications since their high specific strength, and high corrosion resistivity. Besides these properties, titanium is an excellent biocompatible material widely used for internal body implants. Because the products have complex geometries in both applications, Additive Manufacturing (AM) methods have been recently applied for production. AM methods can process a direct 3-D shape of the final product, decrease total production time and cost. However, high residual stress of the final product limits the application of AM components, especially the ones that are exposed to cyclic loading. In the present study, the initial ...


Spatial Transferability Assessment Of A Composite Walkability Index: The Pedestrian Index Of The Environment (Pie), Gabriel Lefebvre-Ropars, Catherine Morency, Patrick A. Singleton, Kelly J. Clifton Dec 2017

Spatial Transferability Assessment Of A Composite Walkability Index: The Pedestrian Index Of The Environment (Pie), Gabriel Lefebvre-Ropars, Catherine Morency, Patrick A. Singleton, Kelly J. Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

This paper analyzes the transferability of a composite walkability index, the Pedestrian Index of the Environment (PIE), to the Greater Montréal Area (GMA). The PIE was developed in Portland, Oregon, and is based on proprietary data. It combines six urban form variables into a score ranging from 20 to 100. The measure introduces several methodological refinements which have not been applied concurrently in previous efforts: a wide coverage of the different dimensions of the urban form, together with the use of a distance-based decay function and modelling-based weighing of the variables.


Structural Behavior Of Lap Shear Connections With Thermally Insulating Filler Plates, Salih Qasim Mahmood Dec 2017

Structural Behavior Of Lap Shear Connections With Thermally Insulating Filler Plates, Salih Qasim Mahmood

Dissertations and Theses

This research consists of experimental load tests and numerical simulations of structural steel connections with various filler materials to study the effect of non-steel fillers on the connection strength. Non-steel fillers are used in the steel connections to provide thermal insulation by reducing thermal bridging. Eight specimens having steel and polypropylene filler plates of various thicknesses were tested in the laboratory. The collected data were compared to a Finite Element Analysis (FEA) using ABAQUS to validate the numerical results. After validation, three parametric studies were conducted using ABAQUS to provide insight into general behavior of connections with a variety of ...


Technology Planning For Aligning Emerging Business Models And Regulatory Structures: The Case Of Electric Vehicle Charging And The Smart Grid, Kelly R. Cowan Dec 2017

Technology Planning For Aligning Emerging Business Models And Regulatory Structures: The Case Of Electric Vehicle Charging And The Smart Grid, Kelly R. Cowan

Dissertations and Theses

Smart grid has been described as the Energy Internet: Where Energy Technology meets Information Technology. The incorporation of such technology into vast existing utility infrastructures offers many advantages, including possibilities for new smart appliances, energy management systems, better integration of renewable energy, value added services, and new business models, both for supply- and demand-side management. Smart grid also replaces aging utility technologies that are becoming increasingly unreliable, as the average ages for many critical components in utility systems now exceed their original design lives. However, while smart grid offers the promise of revolutionizing utility delivery systems, many questions remain about ...


Utilizing High-Resolution Archived Transit Data To Study Before-And-After Travel-Speed And Travel-Time Conditions, Travis Bradley Glick Dec 2017

Utilizing High-Resolution Archived Transit Data To Study Before-And-After Travel-Speed And Travel-Time Conditions, Travis Bradley Glick

Dissertations and Theses

Travel times, operating speeds, and service reliability influence costs and service attractiveness. This paper outlines an approach to quantify how these metrics change after a modification of roadway design or transit routes using archived transit data. The Tri-County Metropolitan Transportation District of Oregon (TriMet), Portland's public transportation provider, archives automatic vehicle location (AVL) data for all buses as part of their bus dispatch system (BDS). This research combines three types of AVL data (stop event, stop disturbance, and high-resolution) to create a detailed account of transit behavior; this probe data gives insights into the behavior of transit as well ...


Physics Based Approach For Seafloor Classification, Phu Duy Nguyen Dec 2017

Physics Based Approach For Seafloor Classification, Phu Duy Nguyen

Dissertations and Theses

The seafloor properties are of high importance for many applications such as marine biology, oil and gas exploration, laying cables, dredging operations and off-shore construction. Several approaches exist to classify the properties of the seabed. These include taking direct samples of the seabed (e.g., coring), however, these methods are costly and slow. Underwater acoustic remote sensing techniques are of interest because they are lower cost and faster. The information about the seabed properties can be extracted by studying the energy of single beam echo sounders (SBES). This can be done by either phenomenological or numerical methods [1], [2]. This ...


Video Frame Interpolation Via Adaptive Separable Convolution, Simon Niklaus, Long Mai, Feng Liu Dec 2017

Video Frame Interpolation Via Adaptive Separable Convolution, Simon Niklaus, Long Mai, Feng Liu

Computer Science Faculty Publications and Presentations

Standard video frame interpolation methods first estimate optical flow between input frames and then synthesize an intermediate frame guided by motion. Recent approaches merge these two steps into a single convolution process by convolving input frames with spatially adaptive kernels that account for motion and re-sampling simultaneously. These methods require large kernels to handle large motion, which limits the number of pixels whose kernels can be estimated at once due to the large memory demand. To address this problem, this paper formulates frame interpolation as local separable convolution over input frames using pairs of 1D kernels. Compared to regular 2D ...


Energy Efficiency Measures In Oregon Instructional School Facilities Implemented Under Sb 1149, And Improved Student Performance, Virginia Saraswati, Timothy Hulseman, John Bauer Dec 2017

Energy Efficiency Measures In Oregon Instructional School Facilities Implemented Under Sb 1149, And Improved Student Performance, Virginia Saraswati, Timothy Hulseman, John Bauer

Engineering and Technology Management Faculty Publications and Presentations

Energy generation, transmission, and distribution, requires a costly infrastructure to meet increasing demand. The success of energy efficiency measures (EEM's) are largely based on cumulative energy and cost savings. This research attempts to add improved student learning to the list of benefits when implementing EEM's in instructional school facilities. Our literature review of current research demonstrates that maximizing natural daylight in the design of school buildings reduces energy consumption, as well as improves student performance [1]. Additionally, EEM's can benefit student performance through direct and indirect environmental improvements that enhance usability, productivity, and comfort [2]. Through statistical ...


Technology Readiness Levels Improving R&D Management: A Grounded Theory Analysis, Joao Ricardo Lavoie, Tugrul Unsal Daim Dec 2017

Technology Readiness Levels Improving R&D Management: A Grounded Theory Analysis, Joao Ricardo Lavoie, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

The strategic management of an organization is well understood and there are several different frameworks and methodologies available to develop and implement strategies that will put the organization on the right track and make it more competitive. Nevertheless, the ability to manage technology and to assess and choose the right technologies to be used and to be invested in is not that well understood and developed. The technology readiness is important to be measured and managed, so that organizations have the chance to make better decisions on which technologies to rely on and when. Technology Readiness Levels (TRL) is a ...


A Comparison Of Two Innovation Tools: Application On Smart Kitchen Design, Burcu Taşkın Dec 2017

A Comparison Of Two Innovation Tools: Application On Smart Kitchen Design, Burcu Taşkın

Electrical and Computer Engineering Faculty Publications and Presentations

The process is one of the significant issues of companies in innovative product design. The designers and the management deal with producing high quality products with the creativity in a short-term period. The researchers developed techniques to solve that problem as TRIZ. The TRIZ-based techniques aim to recover the gaps of the creative innovation to solve specific problems of technical products and technologies. However, the traditional innovation techniques are still preferred for the design process. This study conducted a comparative research on outcomes regarding the process of two design groups. The assignment is given to ten design students to identify ...


Knowledge Flows And Influence In Online Social Networks: Proposing A Research Agenda, Charles M. Weber, Nitin V. Mayande Dec 2017

Knowledge Flows And Influence In Online Social Networks: Proposing A Research Agenda, Charles M. Weber, Nitin V. Mayande

Engineering and Technology Management Faculty Publications and Presentations

Online social networks, which have been defined as aggregated organizations that emerge from the Internet when people carry on public discussions, are increasingly becoming the vehicle of influence in social, political and economic discourse. Yet, despite its increasing importance, the nature of influence in online social networks is not really understood. Practitioners openly admit that they lack the experience to make sense of the phenomenon, and extant theory of influence in networks, which extrapolates from observations of the real world, is demonstrably inadequate when it comes to explaining influence online. The paper introduces a novel approach to analyzing influence online ...


Improving The Effectiveness Of Fuzzy Front End Management: Expanding Stage-Gate Methodologies Through Agile, Aruna Bhatia, Juchun Cheng, Sadaf Salek, Vidhi Chokshi, Antonie J. Jetter Dec 2017

Improving The Effectiveness Of Fuzzy Front End Management: Expanding Stage-Gate Methodologies Through Agile, Aruna Bhatia, Juchun Cheng, Sadaf Salek, Vidhi Chokshi, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

More now than ever before, product development has become more challenging and complex with all the globalization around business today. Understanding the requirements of unfamiliar markets can be very challenging for organizations trying to speed-up their innovations. Also with the advent of globalization there is pressure on everyone to perform better and roll out new products in the market. The fuzzy front end process is very dynamic and unstructured process. By taking advantage of the key characteristics of Agile and Stage-Gate model, an Integrated Agile- Stage- Gate Hybrid model was developed which could help in improving the effectiveness of the ...


Monitoring And Anticipating The Convergence Of Lighting Control Strategies, Nina Chaichi, Tugrul Unsal Daim Dec 2017

Monitoring And Anticipating The Convergence Of Lighting Control Strategies, Nina Chaichi, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

IPC co-classification in conjunction with cross impact analysis has been used to identify technology convergence and its strength over specific period of time. In this study, we tried to monitor the convergence of lighting control strategies which yields energy efficiency from 2009 to 2013. Also, we tried to anticipate the trend of impacts for near future. We take new approach to utilize detailed information including rate of change of co-classified patents, number of patents in each class, and convergence strength between two classes over time and build possible scenarios to anticipate the convergence trend. In our new approach, convergence strength ...


Contextual Differentiation Of Absorptive Capacity: Empirical And Conceptual Development, Marina Dabic, Ernest Vlačić, Tugrul Unsal Daim Dec 2017

Contextual Differentiation Of Absorptive Capacity: Empirical And Conceptual Development, Marina Dabic, Ernest Vlačić, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

This paper is focused on the research and operationalization of the absorption capacity in technology driven firms with a particular focus on their technology based innovation performances, which is widely recognised as a means of achieving and maintaining the firms' competitive advantage. Although research in the field of absorption capacity was globally initiated more than two and a half decades ago, the same was not at all the case with Eastern European firms. Considering that, the research objective of this paper arises: what is the level of the absorptive capacity in technology driven Croatian firms and how does it catalyse ...


Benchmarking Of Technology Roadmapping Process In Energy Sector: A Literature Review, Chih-Jen Yu, Tugrul Unsal Daim Dec 2017

Benchmarking Of Technology Roadmapping Process In Energy Sector: A Literature Review, Chih-Jen Yu, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

Technology roadmapping (TRM) has been recognized as an effective and flexible technology planning tool to assist company, industry, or nations to layout their strategic technology needs and align their vision and strategic objectives. Technology roadmap have been developed into various types and formats, by means of generic or customized processes, to suit specific organizational requirement in different industry settings such as energy sector. However, evaluating the effectiveness of roadmapping process remains a critical issue for roadmap updating and improvement. This paper proposes a benchmark approach based on a literature review to help develop a comparative model with required checklists.


Multi-Dimensional Drought Risk Assessment Based On Socio-Economic Vulnerabilities And Hydro-Climatological Factors, Ali Ahmadalipour Nov 2017

Multi-Dimensional Drought Risk Assessment Based On Socio-Economic Vulnerabilities And Hydro-Climatological Factors, Ali Ahmadalipour

Dissertations and Theses

Drought is among the costliest natural hazards developing slowly and affecting large areas, which imposes severe consequences on society and economy. Anthropogenic climate change is expected to exacerbate drought in various regions of the globe, making its associated socioeconomic impacts more severe. Such impacts are of higher concern in Africa, which is mainly characterized by arid climate and lacking infrastructure as well as social development. Furthermore, the continent is expected to experience vast population growth, which will make it more vulnerable to the adverse effects of drought. This study provides the first comprehensive multi-dimensional assessment of drought risk across the ...


Ensemble Machine Learning And Forecasting Can Achieve 99% Uptime For Rural Handpumps, Daniel L. Wilson, Jeremy R. Coyle, Evan A. Thomas Nov 2017

Ensemble Machine Learning And Forecasting Can Achieve 99% Uptime For Rural Handpumps, Daniel L. Wilson, Jeremy R. Coyle, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Broken water pumps continue to impede efforts to deliver clean and economically-viable water to the global poor. The literature has demonstrated that customers’ health benefits and willingness to pay for clean water are best realized when clean water infrastructure performs extremely well (>99% uptime). In this paper, we used sensor data from 42 Afridev-brand handpumps observed for 14 months in western Kenya to demonstrate how sensors and supervised ensemble machine learning could be used to increase total fleet uptime from a best-practices baseline of about 70% to >99%. We accomplish this increase in uptime by forecasting pump failures and identifying ...


Analysis Of The Acid-Base Balance Of Mainstream Tobacco Smoke And Its Effect On The Gas/Particle Partitioning Of Nicotine, Amy Kathleen Devita-Mcbride Nov 2017

Analysis Of The Acid-Base Balance Of Mainstream Tobacco Smoke And Its Effect On The Gas/Particle Partitioning Of Nicotine, Amy Kathleen Devita-Mcbride

Dissertations and Theses

Tobacco smoke particulate matter (PM) is a complex mixture of condensed organic compounds, with about 5 to 10% water. Its general properties are similar in some respects to that of atmospheric organic aerosol PM and thus provides a useful surrogate when studying atmospheric PM. Due to its ability to undergo acid-base chemistry, nicotine is of particular interest in the tobacco smoke system. The gas/particle partitioning of nicotine depends on the protonation state of nicotine in the particles, so the distribution of nicotine between these phases provides a means of understanding the acid-base balance in the tobacco smoke system. The ...


Elution Tailing Of Nonaqueous Phase Liquids In Porous Media, Louisa Orr Nov 2017

Elution Tailing Of Nonaqueous Phase Liquids In Porous Media, Louisa Orr

Civil and Environmental Engineering Undergraduate Honors Theses

A variety of porous media were studied to characterize contaminant dispersion over time. This work looked at a compilation of previously published studies to investigate the dependence of long term elution tailing trends on particular soil characteristics. Recession curve analysis was conducted on existing dispersed contaminant literature, to yeild the low-concentration recession constant (K). The R2 values correlating the soil properties to contaminant concentration ranged from 0.12494 to 0.95429. The low-concentration recession constant (K) values ranged from 0.9745407 0.9999988. The relationship between K and the soil properties porosity, organic carbon, and fines fraction is increasing ...


Countywide Bluetooth System: Use Cases & Performance Measures, Shaun Quayle Nov 2017

Countywide Bluetooth System: Use Cases & Performance Measures, Shaun Quayle

TREC Friday Seminar Series

Washington County has 124 permanent roadside Bluetooth readers, which passively and in an anonymous fashion collect travel time, speed, and origin-destination information across the major arterials in the urban County. This presentation gives an overview of the program purpose, history, some interesting use cases, and the formation of comparative performance metrics to gauge the magnitude and duration of congestion across the County. These metrics and information will help planners improve travel demand models, consultants improve traffic analyses, operations staff prioritize timing, detection, and maintenance functions, agencies inform traveler information data, and leaders better communicate the story of traffic demand, delay ...


Tidal Variability Related To Sea Level Variability In The Pacific Ocean, Adam Thomas Devlin, David A. Jay, Edward Zaron, Stefan A. Talke, Jiayi Pan, Hui Lin Nov 2017

Tidal Variability Related To Sea Level Variability In The Pacific Ocean, Adam Thomas Devlin, David A. Jay, Edward Zaron, Stefan A. Talke, Jiayi Pan, Hui Lin

Civil and Environmental Engineering Faculty Publications and Presentations

Ocean tides are changing worldwide for reasons unrelated to astronomical forcing. Changes in tidal properties coupled with altered mean sea level (MSL) may yield higher peak water levels and increased occurrence of short-term exceedance events, such as storm surge and nuisance flooding. Here we investigate the hypothesis that changes in relative sea level are correlated with alterations in tidal amplitudes. Our approach focuses on the correlation between short-term (monthly to interannual) fluctuations in sea level with changes in tidal properties of major ocean tides (M2, and K1; S2 and O1) at 152 gauges. Results suggest that ...


Evaluation Of Roadway Reallocation Projects, Miguel Figliozzi Nov 2017

Evaluation Of Roadway Reallocation Projects, Miguel Figliozzi

TREC Project Briefs

This NITC study offers a new methodology for evaluating the before-and-after effects of roadway space reallocation projects.


Evaluating The Performance Of Contech’S Stormfilter With Zpg Media Under The City Of Portland’S 2016 Stormwater Management Manual Requirements For Manufactured Stormwater Treatment Technologies, Mawj T.H. Khammas Nov 2017

Evaluating The Performance Of Contech’S Stormfilter With Zpg Media Under The City Of Portland’S 2016 Stormwater Management Manual Requirements For Manufactured Stormwater Treatment Technologies, Mawj T.H. Khammas

Civil and Environmental Engineering Master's Project Reports

Stormwater runoff is the water generated from excess rainfall or snowmelt that flows over impervious surfaces such as paved roads, parking lots, and on roofs, it often carries a variety of pollutants that adversely affect water quality in that region. Portland is a well-developed city; the majority of the streets are paved and impervious and will consequently generate a tremendous amount of stormwater this creates the necessity for management to help preserve and mimic natural hydrologic cycle through improving water quality. The StormFilter® with ZPG media, manufactured by CONTECH, is a manufactured stormwater treatment technology(MSTT) in which zeolite, perlite ...


Fast On-Line Kernel Density Estimation For Active Object Localization, Anthony D. Rhodes, Max H. Quinn, Melanie Mitchell Nov 2017

Fast On-Line Kernel Density Estimation For Active Object Localization, Anthony D. Rhodes, Max H. Quinn, Melanie Mitchell

Computer Science Faculty Publications and Presentations

A major goal of computer vision is to enable computers to interpret visual situations—abstract concepts (e.g., “a person walking a dog,” “a crowd waiting for a bus,” “a picnic”) whose image instantiations are linked more by their common spatial and semantic structure than by low-level visual similarity. In this paper, we propose a novel method for prior learning and active object localization for this kind of knowledge-driven search in static images. In our system, prior situation knowledge is captured by a set of flexible, kernel-based density estimations— a situation model—that represent the expected spatial structure of the ...


Evaluation Of Roadway Reallocation Projects: Analysis Of Before-And-After Travel Speeds And Congestion Utilizing High-Resolution Bus Transit Data, Miguel A. Figliozzi, Travis B. Glick Nov 2017

Evaluation Of Roadway Reallocation Projects: Analysis Of Before-And-After Travel Speeds And Congestion Utilizing High-Resolution Bus Transit Data, Miguel A. Figliozzi, Travis B. Glick

TREC Final Reports

The traditional process of identifying corridors for road diet improvements involves selecting potential corridors (mostly based on identifying fourlane roads) and conducting a traffic impact analysis of proposed changes on a selected roadway before implementing changes. The evaluation of roadway reallocation projects should include the analysis of traffic volumes, level of service, speeds, queue lengths and bus operations. There are tools and equipment to evaluate effectively traffic volumes and level of service changes in before-and-after studies. However, the detailed evaluation of speed and queue length distributions along a segment are significantly more cumbersome. In addition, the exhaustive evaluation of bus ...


Webinar: Transportation Benefits Of Parking Cash-Out, Pre-Tax Commuter Benefits, And Parking Surtaxes, Allen Greenberg, James Choe, Sonika Sethi, Colleen Stoll Oct 2017

Webinar: Transportation Benefits Of Parking Cash-Out, Pre-Tax Commuter Benefits, And Parking Surtaxes, Allen Greenberg, James Choe, Sonika Sethi, Colleen Stoll

TREC Webinar Series

The vast majority of employers provide their employees free parking at work, which encourages employees to drive alone. Multiple strategies exist to level the playing field between travel modes and allow employees to select the travel option most beneficial to them without suffering a financial penalty. The U.S. Department of Transportation, Federal Highway Administration sponsored a study to understand the effect parking cash out, pre-tax commuter benefits, and parking surtaxes can have on congestion, emissions, and other driving-related externalities. The study is part of the Administration’s ongoing efforts to increase awareness of solutions to address the transportation issues ...


Advisory Bike Lanes In North America, Michael Williams Oct 2017

Advisory Bike Lanes In North America, Michael Williams

TREC Friday Seminar Series

Despite being used successfully for decades in Europe, Advisory Bike Lanes are an emerging facility type in North America and can be an effective tool for communities wishing to provide bicycle lanes on streets that are otherwise too narrow to accommodate them. This talk will introduce the concept and operation of advisory bike lanes and look at some lessons learned from the early installations of this facility in the U.S. and Canada.


An Analysis Of The Optimal Mix Of Global Energy Resources And The Potential Need For Geoengineering Using The Ceagom Model, John George Anasis, M. A. K. Khalil, George G. Lendaris, Christopher L. Butenhoff, Randall Bluffstone Oct 2017

An Analysis Of The Optimal Mix Of Global Energy Resources And The Potential Need For Geoengineering Using The Ceagom Model, John George Anasis, M. A. K. Khalil, George G. Lendaris, Christopher L. Butenhoff, Randall Bluffstone

Systems Science Faculty Publications and Presentations

Humanity faces tremendous challenges as a result of anthropogenic climate change caused by greenhouse gas emissions. The mix of resources deployed in order to meet the energy needs of a growing global population is key to addressing the climate change issue. The goal of this research is to examine the optimal mix of energy resources that should be deployed to meet a forecast global energy demand while still meeting desired climate targets. The research includes the unique feature of examining the role that geoengineering can play in this optimization. The results show that some form of geoengineering is likely to ...


Safety Effectiveness Of Pedestrian Crossing Treatments, Christopher Monsere Oct 2017

Safety Effectiveness Of Pedestrian Crossing Treatments, Christopher Monsere

TREC Friday Seminar Series

Over the last decade, the transportation agencies in Oregon have systematically enhanced many pedestrian crossings at mid-block locations with Rectangular Rapid Flashing Beacons (RRFBs), Flashing Yellow Beacons (Flash), and high visibility crosswalk markings (Hi-Vis). Enhancements often included the installation of refuge medians. This study explored the safety performance of these enhanced crossings, categorized by enhancement type. Data were collected on 191 crossings that included installation year, geometric features, surrounding land use, traffic volumes, and the number of crashes. Because pedestrian volume at the locations was unavailable, a pedestrian activity level variable was developed. Target crashes for analysis were identified as ...


Optimizing Student Workforce Scheduling At Psu Office Of Information Technology (Oit), Agam Ebramsyah, Aishwarya Joy, Cody Miller, Jake Stevens, Priyanka Patil Oct 2017

Optimizing Student Workforce Scheduling At Psu Office Of Information Technology (Oit), Agam Ebramsyah, Aishwarya Joy, Cody Miller, Jake Stevens, Priyanka Patil

Engineering and Technology Management Student Projects

A significant challenge for businesses of any size, is generating a work schedule that ensures adequate personnel coverage to ensure all aspects of the business are properly staffed, while preventing waste produced from having an excess number of employees working at a given time. The decision to manually create spreadsheets and work schedules that take into account availability, staffing requirements, and cost efficiency can become overwhelming and labor intensive. For Portland State University's Office of Information Technology (OIT), there is a significant challenge in scheduling student workers, while ensuring staffing requirements are met, student work hour restrictions are observed ...