Engineering Commons^™

Heat Pump Cooling And Greenhouse Microclimates In Open And Confined Greenhouse Systems, Ilhami Yildiz, D. P. Stombaugh

BioResource and Agricultural Engineering

The purpose of this study was to determine and compare the performances of conventional and heat pump systems for cooling open and closed loop (confined) greenhouse systems. A dynamic simulation model was developed and validated to predict energy and mass exchanges in a greenhouse as a function of dynamic environmental factors. The model has options to evaluate the effects of location, time of the year, orientation, single and double polyethylene glazings, conventional and heat pump heating and cooling systems, CO₂ enrichment, ventilation, variable shading, and the use of night curtains in open and confined greenhouse environments. Variable shading, ventilation …

Osteonal Effects On Elastic Modulus And Fatigue Life In Equine Bone, V. A. Gibson, S. M. Stover, J. C. Gibeling, S. J. Hazelwood, R. B. Martin

Biomedical Engineering

We hypothesized that recently formed, incompletely mineralized, and thus, relatively deformable osteons in the equine third metacarpus enhance in vitro load-controlled fatigue life in two ways. Macroscopically, there is a compliance effect, because reduced tissue elastic modulus diminishes the stress required to reach a given strain. Microscopically, there is a cement line effect, in which new osteons and their cement lines more effectively serve as barriers to crack propagation. We studied 18 4×10×100 mm beams from the medial, lateral, and dorsal cortices of metacarpal bones from 6 thoroughbred racehorses. Following load-controlled fatigue testing to fracture in 4 point bending, a …

Recombinant Human Bmp-7 Effectively Prevents Non-Union In Both Young And Old Rats, David J. Hak, Takeshi Makino, Takahiro Niikura, Scott J. Hazelwood, Shane Curtiss, A. Hari Reddi

Biomedical Engineering

The purpose of this study was to evaluate the influence of age on the effectiveness of rhBMP-7 treatment in a fracture with severe periosteal damage that is known to result in non-union formation. Closed stabilized femur fractures were produced in 3-month-old and 18-month-old rats. The fracture site was exposed and 2 mm of the periosteum cauterized circumferentially to impair normal fracture healing. The cauterized fracture site was immediately treated with either 100 mg rhBMP-7 (BMP-7 group), or with 25 xL of vehicle alone (control group). Fracture healing was evaluated with radiographs taken at 3 and 6 weeks. Animals were sacrificed …

Effect Of Time-Based Parameters On The Agility Of A Dynamic Mpc System, A. M. Deif, W. H. Elmaraghy

Industrial Technology and Packaging

This paper presents a dynamic manufacturing planning and control (MPC) system that can maintain agility through the ability to dynamically switch between different policies due to varying market strategies. The dynamic behavior of the developed system is investigated by studying the effect of the time based parameters on responsiveness and cost effectiveness of the system reflected in the natural frequency and the damping of its different configurations. Results showed that the agility requirements are directly affected by the time based parameters of the MPC system: production lead time, capacity scalability delay, and shipment time. This resulted in a better understanding …

A Control Approach To Explore The Dynamics Of Capacity Scalability In Reconfigurable Manufacturing Systems, Ahmed M. Deif, Waguih H. Elmaraghy

Industrial Technology and Packaging

This paper presents a dynamic model and analysis for one of the major characteristics of reconfigurable manufacturing systems (RMSs) capacity scalability. The dynamic model is analyzed using its transfer function. Dynamic characteristics associated with the delay in capacity scalability and how to minimize this delay are discussed using control approaches. The problem of how to supply exact capacity in response to market changes is also examined by solving the dynamic problem of the production offset phenomenon in RMSs. The effect of work in process as a damping factor for production disturbances during capacity scalability is addressed. Finally, a general capacity …

Injection-Locking In Fabry-Perot Quantum-Well Lasers, Xiaomin Jin, Shun-Lien Chuang

Electrical Engineering

No abstract provided.

The Potential For Real-Time Traffic Crash Prediction, Mohamed Abdel-Aty, Anurag Pande, Liang Y. Hsia, Fathy Abdalla

Civil and Environmental Engineering

The development of freeway crash prediction models using intelligent transportation systems (ITS) archived data could be a substantial advancement in the field of real-time traffic management. Such models not only are expected to improve safety but also may go a long way to improve freeway operations by reducing incident-related congestion.

Because there is a need to use real-time traffic data emanating from loop detectors, the approach differs distinctly from previous studies estimating crash frequencies or rates on a certain freeway section through aggregate measures of flow (such as average daily traffic or hourly volumes).

Although the authors try to establish …

Leaching Of Accumulated Soil Salinity Under Drip Irrigation, Charles M. Burt, Brett Isbell

BioResource and Agricultural Engineering

Conducted a reclamation leaching experiment in a drip-irrigated pistachio orchard south of Huron, California, during the winter of 2002-2003. The study was conducted to quantify the leaching water required to remove salts from the effective root zone of trees. This experiment tested a new reclamation leaching technique: multiple lines of low-flow drip tape were used to apply water to the area of salinity accumulation along a tree row. This new technique allows water to be applied where there is salt accumulation along the tree row, as opposed to putting water on the entire area of the field. Since reclamation leaching …

Role Of Higher-"Mode" Pushover Analyses In Seismic Analysis Of Buildings, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

The role of higher-“mode” pushover analyses in seismic analysis of buildings is examined in this paper. It is demonstrated that the higher-“mode” pushover curves reveal plastic hinge mechanisms that are not detected by the first-“mode” or other FEMA-356 force distributions, but these purely local mechanisms are not likely to develop during realistic ground motions in an otherwise regular building without a soft and/or weak story. Furthermore, the conditions necessary for “reversal” of a higher-“mode” pushover curve are examined. It is shown that “reversal” in a higher-“mode” pushover curve occurs after formation of a mechanism if the resultant force above the …

Heat Generation In Municipal Solid Waste Landfills, Nazli Yesiller, James Hanson, Wei-Lien Liu

Civil and Environmental Engineering

This study was conducted to investigate thermal aspects of municipal solid waste landfills as a function of operational conditions and climatic region. Spatial and temporal distributions of waste temperatures were determined at four landfills located in North America (Michigan, New Mexico, Alaska, and British Columbia). Temperatures of wastes at shallow depths (extending to 6 to 8 m depth) and near the edges of a cell (within approximately 20 m) conformed to seasonal temperature variations, whereas steady elevated temperatures (23 to 57°C) with respect to air and ground temperatures were reached at depth and at central locations. Waste temperatures decreased from …

Evaluation Of Cost Effective Sensor Combinations For A Vehicle Precrash Detection System, John Carlin, Charles Birdsong, Peter Schuster, William Thompson, Daniel Kawano

Mechanical Engineering

The future of vehicle safety will benefit greatly from precrash detection -the ability of a motor vehicle to predict the occurrence of an accident before it occurs. There are many different sensor technologies currently available for pre-crash detection. However no single sensor technology has demonstrated enough information gathering capability within the cost constraints of vehicle manufacturers to be used as a stand alone device. A proposed solution consists of combining information from multiple sensors in an intelligent computer algorithm to determine accurate precrash information. In this paper, a list of sensors currently available on motor vehicles and those that show …

Measurement Sensitivity And Accuracy Verification For An Antenna Measurement System, Newlyn Hui, Aloysius Aragon Lubiano, Christopher R. Brito, Dean Arakaki

Electrical Engineering

An antenna measurement system was developed to complement a new rectangular anechoic chamber (20’L x 10’W x 9’7”H) that has been established at California Polytechnic State University (Cal Poly) through donations and financial support from industry and Cal Poly departments and programs. Software algorithms were written to provide four data acquisition methods: continual sweep and step mode for both single and multiple frequencies. Log magnitude and phase information for an antenna under test is captured over a user-specified angular position range and the antenna's radiation pattern is obtained after post processing. Pattern comparisons against theoretical predictions are performed. Finally an …

Conducted Emissions Testing For Electromagnetic Compatibility, Maximilian Moy, Dean Arakaki

Electrical Engineering

Operating frequencies in the gigahertz range is creating an increased need for electromagnetic compatibility (EMC) testing. In the United States, FCC regulations require conformance to radiated and conducted emissions specifications. An EMC laboratory was established at Cal Poly San Luis Obispo (screen room, test instrumentation, and software) and an experiment was developed to explore conducted emissions effects. This paper will describe the test configuration, explain the calibration procedure needed to acquire accurate measurements, and illustrate measurement techniques applied to two example systems. In addition, the data collection process is illustrated through software donated by CKC Laboratories (EMC specialists). To verify …

Work In Progress - An Investigation Into The Effect Of An Institutional Honor Code Policy On Academic Behavior, Donald D. Carpenter, Trevor S. Harding, Cynthia J. Finelli, Matthew Mayhew

Materials Engineering

Research indicates significant cheating at institutions of higher learning; however, evidence indicates that a well-designed and clearly-communicated campus honor code might have a mitigating effect. This is the impetus behind the implementation of an Academic Honor Code Policy at a private university beginning in the fall of 2004. This situation presented a unique opportunity to investigate the potential of an academic honor code to change the culture and behavior at a university. This investigation will involve conducting a longitudinal study on the academic habits of students as they progress through the curriculum and include students whose academic careers began under …

The Ballet Model In Engineering Classes – What Works, What Doesn't, And What's New, Blair London, Lisa Deyo

Materials Engineering

Six different engineering courses were taught using aspects of the classical ballet instruction model in organization, teaching methods, and learning strategies. There was a strong focus on performance. The courses spanned sophomore to senior levels. Some aspects of the ballet model worked well: setting rules for the Sacred Space for learning, the beginning activity (“stretch”), the overall organization of the class session, communicating the known ideal, including historical background, and using demonstrations. Some aspects did not work (thus far): exams are not yet performances on stage, little practice or rehearsal occurs, little competition between students occurs, asking students questions in …

A Case Study On Research In Engineering Education: Designing, Testing, And Administering The Paces-2 Survey On Academic Integrity, Cynthia J. Finelli, Jamie L. Szwalek, Donald D. Carpenter, Trevor S. Harding

Materials Engineering

Most engineering educators excel at planning and conducting technical research in their field, but few are proficient doing this for a project in engineering education. Recently, however, there has been increased emphasis on conducting rigorous research in engineering education. This paper provides practical advice for planning and conducting such research. The authors use their long term project to predict academic dishonesty in engineering college students as a case study representing one approach to research in engineering education. In particular, the authors present the design, testing, and administration of a two-part survey instrument to collect information from college students about their …

Plasma Deposition Of Spin Chucks To Reduce Contamination Of Silicon Wafers, Emir Gurer, Ed C. Lee, Richard Savage

Materials Engineering

An apparatus for delivering a fluidic media to a wafer includes a housing defining a process chamber. A fluidic media delivery member is coupled to the process chamber. A rotatable chuck is positioned in the process chamber. The rotatable chuck has a wafer support surface coated with a coating material. A vacuum supply line is coupled to the rotatable chuck.

Cm Facilities Update, Construction Management Department

Construction Management

No abstract provided.

Proactive Real-Time Traffic Safety Implementation Strategy On Freeways, Mohamed Abdel-Aty, Anurag Pande, Nizam Uddin

Civil and Environmental Engineering

Reactive traffic management strategies such as incident detection are becoming less relevant with the advancement of mobile phone usage. Freeway management in the 21^st century needs to shift focus toward proactive strategies that include anticipating incidents such as the crashes. Predicting crash occurrences would also be the key to traffic safety. A two-step approach to identify freeway locations with high probability of crashes through real-time traffic surveillance data is presented here. For this study historical crash and corresponding traffic data from loop detectors were gathered from a 58-km (36-mile) corridor of Interstate-4. Following an exploratory analysis two types of …

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Final Project Report, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical Deliverables, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Analysis Of Driver Response To Caws Warning Messages, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical And Operational Assessment, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Executive Summary, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Evaluation Of Traffic Safety Influence Based On Historical Collision Data, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

Identification Of Rear-End Crash Patterns On Instrumented Freeways: A Data Mining Approach, A. Pande, M. Abdel-Aty

Civil and Environmental Engineering

Data mining is the analysis of large “observational” datasets to find unsuspected relationships that might be useful to the data owner. It typically involves analysis where objectives of the mining exercise have no bearing on the data collection strategy. Freeway traffic surveillance data collected through underground loop detectors is one such “observational” database maintained for various ITS (Intelligent Transportation Systems) applications such as travel time prediction etc. In this research data mining process is used to relate this surrogate measure of traffic conditions (data from freeway loop detectors) with occurrence of rear-end crashes on freeways. The results from this analysis …

Traffic Surveillance From A Safety Perspective: An Its Data Application, M. Abdel-Aty, A. Pande, N. Uddin

Civil and Environmental Engineering

Reactive traffic management strategies such as incident detection are becoming less relevant with the advancement of mobile phone usage. Freeway management in the 21^st century needs to shift focus toward proactive strategies that include anticipating incidents such as the crashes. “Predicting” crash occurrences would also be the key to traffic safety. A two-step approach to identify freeway locations with high probability of crashes through real-time traffic surveillance data is presented here. For this study historical crash and corresponding traffic data from loop detectors were gathered from a 58-km (36-mile) corridor of Interstate-4. Following an exploratory analysis two types of …

Integrated Temperature And Gas Analysis At A Municipal Solid Waste Landfill, James L. Hanson, Nazli Yesiller, Laurel A. Kendall

Civil and Environmental Engineering

This study is conducted to investigate heat and gas production at a municipal solid waste landfill. Periodic temperature and gas measurements have been taken at approximately 140 locations within the waste mass, liner systems, and cover systems at a midwestern U.S.A. landfill since 1999. Increasing temperatures (1 to 15°C/a) were observed for newly placed wastes whereas steady elevated temperatures (50 to 60°C) were observed in older wastes. Liner temperatures increased at a rate of approximately 2 to 4°C/a and stable elevated temperatures in excess of 30°C were observed after 5.5 years and under 42 m of waste height. Anaerobic decomposition …

Optimization Of The Fuzzy Logic Controller For An Autonomous Uav, Jon C. Ervin, Sema E. Alptekin, Dianne J. Deturris

Industrial and Manufacturing Engineering

In this paper, we describe the optimization of membership functions in an application employing a hierarchical Fuzzy Logic Controller. The size of the rule base is made manageable by using a unique formulation, known as Combs method, to help control the problem of ‘exponential rule expansion’. The optimization is performed using a steady state genetic algorithm with a dynamic fitness function. The controller being developed is designed to fly a small, autonomous parafoil, suitable for short-range reconnaissance and land survey applications. The optimization process is performed in the Matlab/Simulink software environment and incorporates fuzzy logic modules developed in the Matlab …

Coronal Fractures Of The Distal Femoral Condyle: A Biomechanical Evaluation Of Four Internal Fixation Constructs, David J. Hak, James Nguyen, Shane Curtiss, Scott Hazelwood

Biomedical Engineering

This study evaluated different fixation methods in posterior femoral condyle coronal fractures. A standardised osteotomy was created in synthetic composite femurs and fixed with one of four methods (one 3.5 mm diameter screw, two 3.5 mm screws, one 6.5 mm screw, two 6.5 mm screws). The stiffness and mean loads to specified displacements were measured. The stiffness of two 6.5 mm screws was significantly greater than both single 3.5 mm screw (3567 versus 2584 N/mm; p = 0.0075) and double 3.5 mm screws (3567 versus 2080 N/mm; p = 0.003). There was no statistical difference in the stiffness of one …