Other Engineering Commons^™

Fault Detection And Diagnosis Process For Oversizing Design On Multiple Packaged Air-Conditioning Units, Denchai Woradechjumroen, Haorong Li, Thanapat Promwattanapakee

Durham School of Architectural Engineering and Construction: Faculty Publications

Heating, ventilation, air-conditioning and Refrigeration (HVAC&R) systems are seldom designed or commissioned properly. The situation leads to abrupt or degradation faults resulting in inefficient energy uses, excessive energy consumption and high service costs. To solve these aforementioned problems, fault detection and diagnosis (FDD) is utilized to firstly detect any abnormal conditions of a system and then diagnoses and determines their causes. In order to apply this concept in HVAC oversizing designs, this paper proposes the state-of-art procedure of a FDD procedure for analyzing the inherently faulty design (oversizing) of multiple packaged air-conditioning units used to supply cooling for an open …

Compressor Having A Control And Dagnostic Module, Hung M. Pham, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

An apparatus includes a Voltage sensor, a current sensor, and a controller. The Voltage sensor measures Voltage values of alternating current power Supplied to a capacitor. The capaci tor is electrically coupled to a compressor. The current sensor measures current values of the alternating current power. The controller is configured to receive the Voltage values and the current values. The controller is configured to determine a first power factor value based on at least one of the voltage values and at least one of the current values. The controller is configured to selectively detect a first capacitor fault in response …

Subjective Perception Of Varying Reflection Densities In Room Impulse Responses, Hyun Hong

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Reverberation time (RT) is a metric commonly used to describe room acoustic conditions, but different rooms which have the same reverberation time can have different reflection densities. Much less is known about how humans perceive different reflection densities and how sensitive humans are to changes in reflection density. Previous investigations in the existing literature have studied the upper limit of distinguishable reflection density using artificial impulse responses, but not with more realistic impulse responses simulated in room acoustic software or measured from real rooms. The aim of this dissertation is to investigate methods for quantifying reflection density from measured impulse …

Background Differences In Baseline And Stimulated Mmp Levels Influence Abdominal Aortic Aneurysm Susceptibility, Matthew A. Dale, Melissa K. Suh, Shijia Zhao, Trevor Meisinger, Linxia Gu, Vicki J. Swier, Devendra K. Agrawal, Timothy Greiner, Jeffrey S. Carson, B. Timothy Baxter, Wanfen Xiong

Department of Mechanical and Materials Engineering: Faculty Publications

Objective: Evidence has demonstrated profound influence of genetic background on cardiovascular phenotypes. Murine models in Marfan syndrome (MFS) have shown that genetic background-related variations affect thoracic aortic aneurysm formation, rupture, and lifespan of mice. MFS mice with C57Bl/6 genetic background are less susceptible to aneurysm formation compared to the 129/SvEv genetic background. In this study, we hypothesize that susceptibility to abdominal aortic aneurysm (AAA) will be increased in 129/SvEv mice versus C57Bl/6 mice. We tested this hypothesis by assessing differences in aneurysm size, tissue properties, immune response, and MMP expression.

Methods: Mice of C57Bl/6 or 129/SvEv background underwent AAA induction …

Lessons Learned From A Simulation Project In Construction Education, Saeed Rokooei, James D. Goedert

Department of Construction Engineering and Management: Faculty Publications

Virtual Interactive Construction Education (VICE) is a simulation designed for construction education. The purpose was to provide the traditional lecture-based construction contents along with supplementary instructions in a project-based learning environment. Six modules were proposed as a curriculum delivery guideline including: single span bridge, residential building, light commercial, heavy commercial, highway, and segmental bridge. The single span bridge was the first module used for prototype development providing an opportunity to design, analyze, implement, and test for effectiveness. This paper describes the design steps and results of this three-year research project. VICE-Bridge required participants to sequentially order the construction activities and …

Should Nuclear Energy Be More Heavily Incorporated By The United States?, Matthew Romer

Nebraska College Preparatory Academy: Senior Capstone Projects

America is involved in one of the biggest races towards electrical efficiency, cleanliness, and productivity. Nuclear energy is a major part of the U.S.’s non-­‐carbon emitting electricity, and has strict regulations for management. However, this form of energy has been on the decline in the past couple decades due to cost and competition with cheaper, less clean methods. Is nuclear energy feasible enough to continue?

Air Change Rate Vs Airflow Pathway: Bioaerosol Containment And Removal In Patient Rooms, Kevin R. Grosskopf

Durham School of Architectural Engineering and Construction: Faculty Publications

Recent studies have shown that higher air change rates may have the unintended consequence of creating turbulent airflows that entrain high concentrations of infectious particles within the breathing zone, and possibly, breakdown pressure relationships necessary to contain the spread of infectious particles to other clinical spaces.

Chemical Storage Of Wind Energy By Renewable Methanol Production: Feasibility Analysis Using A Multi-Criteria Decision Matrix, Michael J. Matzen, Mahdi H. Alhajji, Yaşar Demirel

Department of Chemical and Biomolecular Engineering: Faculty Publications

This study is for the technoeconomic analysis of an integral facility consisting of wind energy-based electrolytic hydrogen production, bioethanol-based carbon dioxide capture and compression, and direct methanol synthesis. ASPEN Plus was used to simulate the facility producing 97.01 mt (metric tons) methanol/day using 138.37 mt CO₂/day and 18.56 mt H₂/day. A discounted cash flow diagram for the integral facility is used for the economic analysis at various hydrogen production costs and methanol selling prices. The feasibility analysis is based on a multi-criteria decision matrix consisting of economic and sustainability indicators comparing renewable and non-renewable methanol productions. …

Ventilation Rates And Airflow Pathways In Patient Rooms: A Case Study Of Bioaerosol Containment And Removal, Ehsan S. Mousavi, Kevin R. Grosskopf

Durham School of Architectural Engineering and Construction: Faculty Publications

Most studies on the transmission of infectious airborne disease have focused on patient room air changes per hour (ACH) and how ACH provides pathogen dilution and removal. The logical but mostly unproven premise is that greater air change rates reduce the concentration of infectious particles and thus, the probability of airborne disease transmission. Recently, a growing body of research suggests pathways between pathogenic source (patient) and control (exhaust) may be the dominant environmental factor. While increases in airborne disease transmission have been associated with ventilation rates below 2 ACH, comparatively less data are available to quantify the benefits of higher …

Adaptive Predictive Functional Controller, Fadi Alsaleem, Arvind Rao

Durham School of Architectural Engineering and Construction: Faculty Publications

A controller device and a method for controlling a system that utilizes an adaptive mechanism to self-learn the system char acteristics and incorporates this adaptive self-learning ability to predict a control parameter correctly to provide precise control of a system component.

An Adaptive Photovoltaic Topology To Overcome Shading Effect In Pv Systems, Mohamed Amer Chaaban, Lana El Chaar, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

Shading in photovoltaic systems can cause many undesired effects.When shading occurs, the power generated from the PV system is much less than nominal power, increasing the electrical mismatching losses between PV system components. Active research to address this power loss focuses on static and adaptive systems.This paper addresses an adaptive system solution and proposes a new method to adaptively overcome losses due to shading during low radiation conditions. In addition, a statistical analysis for choosing the most feasible and efficient configuration for the system size is presented. The proposed system has been validated under shade conditions in a simulation and …

Building Envelope And Interior Grading Systems And Methods, Fadi Mohammad Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A difference module determines differences between an out door ambient temperature and an indoor temperature, deter mines a first average of the differences, and determines a second average of the differences. A storing module stores a first data point, the first data point including the first average and a first total run time of a heating, ventilation, and/or air conditioning (HVAC) system, and stores a second data point, the second data point including the second average and a second total run time of the HVAC system. A fitting module fits a line to the first and second data points. An …

A Review Of Approaches For Sensing, Understanding, And Improving Occupancy-Related Energy-Use Behaviors In Commercial Buildings, Hamed Nabizadeh Rafsanjani, Changbum R. Ahn, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

Buildings currently account for 30–40 percent of total global energy consumption. In particular, commercial buildings are responsible for about 12 percent of global energy use and 21 percent of the United States’ energy use, and the energy demand of this sector continues to grow faster than other sectors. This increasing rate therefore raises a critical concern about improving the energy performance of commercial buildings. Recently, researchers have investigated ways in which understanding and improving occupants’ energy-consuming behaviors could function as a cost-effective approach to decreasing commercial buildings’ energy demands. The objective of this paper is to present a detailed, up-to-date …

Use Of Fiber-Reinforced Cements In Masonry Construction And Structural Rehabilitation, Ece Erdogmus

Durham School of Architectural Engineering and Construction: Faculty Publications

The use of fiber reinforcement in traditional concrete mixes has been extensively studied and has been slowly finding its regular use in practice. In contrast, opportunities for the use of fibers in masonry applications and structural rehabilitation projects (masonry and concrete structures) have not been as deeply investigated, where the base matrix may be a weaker cementitious mixture. This paper will summarize the findings of the author’s research over the past 10 years in these particular applications of fiber reinforced cements (FRC). For masonry, considering both mortar and mortar-unit bond characteristics, a 0.5% volume fraction of micro fibers in type …

Agricultural Industry Advanced Vehicle Technology: Benchmark Study For Reduction In Petroleum Use, Roger M. Hoy, Rodney Rohrer, Adam Liska, Joe D. Luck, Loren Isom, Deepak R. Keshwani

Adam Liska Papers

Diesel use on farms in the United States has remained relatively constant since 1985, decreasing slightly in 2009, which may be attributed to price increases and the economic recession. During this time, the United States’ harvested area also has remained relatively constant at roughly 300 million acres. In 2010, farm diesel use was 5.4% of the total United States diesel use. Crops accounting for an estimated 65% of United States farm diesel use include corn, soybean, wheat, hay, and alfalfa, respectively, based on harvested crop area and a recent analysis of estimated fuel use by crop. Diesel use in these …

Nuts & Bolts, Volume 2, Issue 2, Lance Todd, Julie Thomson, Louis Leviticus

Friends of the Larsen Tractor Museum

Museum Open House is a Success

The Passing of Museum Volunteer Larry Ehlers

Larsen Museum to Auction Twelve Tractors

Details an Estate Planning and Memorial Designation

Method And System For Optimal Coordination Control And Soft Repair Of Multiple Rooftop Heating And Cooling Units, Haorong Li

Durham School of Architectural Engineering and Construction: Faculty Publications

Techniques are described that may be implemented in an adaptive control device to regulate multiple zone environmental units based upon multiple temperature values and multiple airflow values, where each temperature value and each airflow value is related to the temperature and the airflow in a specific zone. In an implementation, the input interface of the adaptive control device is configured to receive multiple temperature values and multiple air flow values from multiple zone sensors. The adaptive control device may calculate multiple operational values based on the multiple temperature values and the multiple air flow values. An operational value indicates a …

Virtual Surface Temperature Sensor For Multi-Zone Commercial Buildings, Yuebin Yu, Denchai Woradechjumroen, Daihong Yu

Durham School of Architectural Engineering and Construction: Faculty Publications

Multi-zone structure is commonly used in small commercial office buildings, retail stores and supermarket. While there is no adjacent wall between the zones, the impact of a neighbor zone on the current zone can be approximated and analyzed through the application of virtual walls. It is critical to accurately estimate the virtual wall surface temperature in order to evaluate the model uncertainty and apply improved supervisory control on multiple rooftop air-conditioning units (RTUs). We propose an innovative virtual surface temperature sensor based on system-identification to solve this challenge. The validation of the virtual temperature model is processed by the three …

The Influence Of National Culture On Effectiveness Of Safety Trainings During Postdisaster Reconstruction, Behzad Esmaeili, Kevin Grosskopf, Amy Javernick-Will

Durham School of Architectural Engineering and Construction: Faculty Publications

Non-English speaking workers constitute a disproportionately high number of workers involved in postdisaster reconstruction. Additionally, the rate of fatality among these workers is higher than the industry average. Research shows this population is more prone to unsafe behaviors in the working environment, conceivably because many of these workers are sent into the field prior to any formalized training. Recent studies show that the native culture of construction workers can impact risk-taking behavior. While numerous researchers have attempted to develop training materials for Hispanic workers, the number of studies that consider the impact of native culture on safety behavior is minimal. …

Shallow Flat Soffit Precast Concrete Floor System, George Morcous, Maher Tadros

Durham School of Architectural Engineering and Construction: Faculty Publications

A precast concrete floor system that eliminates the need for column corbels and beam ledges while being very shallow. The main advantages of the present system include a span to-depth ratio of 30, a flat soffit, economy, consistency with prevailing erection techniques, and fire and corrosion protection. The present system consists of continuous precast columns, prestressed rectangular beams, hollow-core planks, and cast-in-place composite topping. Testing results have indicated that a 12 inch deep flat soffit precast floor system has adequate capacity to carry gravity loads (including 100 psf live load) in a 30 ft x 30 ft bay size. Testing …

Hybrid Of Natural Element Method (Nem) With Genetic Algorithm (Ga) To Find Critical Slip Surface, Shahriar Shahrokhabadi, Vahid Khoshfahm, Hamed Nabizadeh Rafsanjani

Durham School of Architectural Engineering and Construction: Faculty Publications

One of the most important issues in geotechnical engineering is the slope stability analysis for determination of the factor of safety and the probable slip surface. Finite Element Method (FEM) is well suited for numerical study of advanced geotechnical problems. However, mesh requirements of FEM creates some difficulties for solution processing in certain problems. Recently, motivated by these limitations, several new Meshfree methods such as Natural Element Method (NEM) have been used to analyze engineering problems. This paper presents advantages of using NEM in 2D slope stability analysis and Genetic Algorithm (GA) optimization to determine the probable slip surface and …

Equipment Fragility Due To Shock Response, Christopher Y. Tuan

Department of Civil and Environmental Engineering: Faculty Publications

Because of its simplicity, the shock response spectrum has become widely used as a means of describing the shock responses and fragilities of structures and equipment. This paper focuses on the drawbacks of using the shock response spectrum for defining equipment shock tolerance. A cantilever beam with a tip mass was used to model a hypothetical piece of equipment subjected to strong ground motion such as that caused by an explosion. The exact solution from a detailed modal analysis shows that multiple modes of response were excited. Contributions from higher modes can be more predominant than that from the fundamental …

Effects Of Time Varying Background Noise Conditions On Human Perception And Performance, Andrew H. Hathaway

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This thesis was designed to study the effects of changing noise conditions on human perception and performance. In two phases, participants were exposed to a number of noise conditions and their performance on an arithmetic task involving short-term memory was monitored and their subjective perception of noise conditions was collected via questionnaires.

In the first phase, participants were tested while being subjected to RC-29(H) and RC-47(RV) conditions created by broadband noise fluctuating on different time intervals, resembling the changing noise conditions potentially found in modern HVAC systems. These intervals varied from two minutes to ten minutes. Results show a significant …

A Simple Method For Estimation Of Queue Length, S. P. Anusha, Lelitha Devi Vanajakshi, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

Urban arterials are characterized by frequent intersections. Queue length and delay are the two primary measures of performance of intersection. These measures play a primary role in determining the arterial performance. This article presents a methodology to determine the number of vehicles in queue at a signalized intersection for under saturated traffic conditions. The results obtained were validated using actual values that are manually extracted. The root-mean-square error is of the range 1.3 vehicles for estimation of number of vehicles in queue. The various aspects that have to be considered in accurate estimation of performance measures are also discussed.

Nuts & Bolts, Volume 1, Issue 4

Friends of the Larsen Tractor Museum

Splinter Gallery Construction

Restoration Club

Museum OLLI Program

Free Webinar: Ethanol in Legacy Engines

Investigation Of Sound Transmission Through An Open Window Into A Room, Caleb F. Sieck

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

In recent decades, noise levels in cities and the associated annoyance and health consequences have become regular topics of discussion. As a result, the assessment of environmental noise transmitting into buildings has received much attention. Current models of sound transmission through open windows have either neglected their thickness or the presence of a room behind on one side. The objectives of the present work were to (1) develop an accurate analytical model of sound transmission through an open window of finite thickness into a room, (2) verify the analytical model using a finite element model and experimental measurements, and (3) …

Nuts & Bolts, Volume 1, Issue 3

Friends of the Larsen Tractor Museum

Museum Open House
Calling All Tractor Clubs
Allis WC Donation
Tractor Show Information

Friends Of The Lester F. Larsen Tractor Test & Power Museum Newsletter, Spring 2013

Friends of the Larsen Tractor Museum

Membership renewal

Annual Meeting, May 17, 2013

Honoring William E. Splinter

Environmentally Friendly Sizing Agent From Corn Distillers Dried Grains, Yue Zhang

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Distillers dried grains (DDGS), the coproducts of corn ethanol production, were used as a textile sizing agent on cotton, polyester and polyester/cotton blends in an effort to find inexpensive and biodegradable alternatives to sizing agents such as poly(vinyl alcohol) that are currently used. Although DDGS is an inexpensive, biodegradable and abundant co-product, it has limited industrial applications. DDGS is a mixture of carbohydrates, proteins and oil which are used as sizing agents or as size additives. The effects of DDGS extraction conditions on sizing evaluation parameters such as fiber adhesion, film properties, viscosity and fabric abrasion were studied in comparison …

Multi-Objective Time-Cost Optimization Using Cobb-Douglas Production Function And Hybrid Genetic Algorithm, Zhigang Shen, Ashkan Hassani, Qian Shi

Durham School of Architectural Engineering and Construction: Faculty Publications

Existing research on construction time-cost tradeoff issues rarely explore the origin of the crashing cost. Crashing cost function was either assumed without much justification, or came from historical data of some real projects. As a result the conclusions of the papers can hardly be used to guide allocations of labor and equipment resources respectively. The authors believe Cobb-Douglas function provides a much-needed piece to modeling the cost functions in the construction time-cost tradeoff problem during the crashing process. We believe this new perspective fills a gap of existing time-cost tradeoff research by considering project duration, labor and equipment cost as …