Effects Of Building Mechanical System Noise On Worker Performance And Perception,
2010
University of Nebraska - Lincoln
Effects Of Building Mechanical System Noise On Worker Performance And Perception, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
This paper presents results from a number of studies that investigated the effects of noise from building mechanical systems on human task performance and perception. Three phases of research were conducted, each of which utilized a different set of noise signals produced by building mechanical systems: (1) broadband noise at different levels and spectral qualities; (2) tonal noise conditions; and (3) noise conditions with time-varying fluctuations. In each phase, at least six different noise signals (many based on in-situ measurements) were reproduced in an office-like setting. Thirty participants completed tasks (e.g. typing, grammatical reasoning, math) plus subjective questionnaires, while exposed …
Breaking The Mould 5 : Comparative Simulation Of Internal Insulation Systems,
2010
Technological University Dublin
Breaking The Mould 5 : Comparative Simulation Of Internal Insulation Systems, Joseph Little
Articles
In the last edition of Construct Ireland ‘Breaking the Mould IV’ established the standard that should be used to evaluate thermal upgrades of single leaf walls, described steps to physically prepare the wall, explained some of the mechanisms that affect the likelihood of mould and gave criteria for judging the simulations outputs. The next step is to simulate a number of permutations of typical internal insulation systems using WUFI Pro under IS EN 15026.
Investigation Of The Thermal Conductivity Of Compacted Silts And Its Correlation To The Elastic Modulus,
2010
Missouri University of Science and Technology
Investigation Of The Thermal Conductivity Of Compacted Silts And Its Correlation To The Elastic Modulus, Robert D. Hotz, Louis Ge
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Thermal conductivity measurement is a quick and easy test for compacted soils. This study presents the results of thermal conductivity testing on silt compacted under standard and modified Proctor efforts. a comparison of moisture content measurements from both lab oven and field oven is also presented and discussed. Measured thermal conductivity was correlated to the bulk density and water content. It is further correlated to Young's modulus and Shear modulus of the compacted silt, which were determined through ultrasonic pulse velocity measurements. Several trends were observed which may be used to correlate soil thermal conductivity of the compacted silt to …
How And What To Communicate For Efficient Joist Design,
2010
California Polytechnic State University - San Luis Obispo
How And What To Communicate For Efficient Joist Design, John Lawson, Bruce Brothersen
Architectural Engineering
No abstract provided.
On The Turbulent Prandtl Number In Homogeneous Stably Stratified Turbulence,
2010
Missouri University of Science and Technology
On The Turbulent Prandtl Number In Homogeneous Stably Stratified Turbulence, Subhas K. Venayagamoorthy, Derek D. Stretch
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
In this paper, we derive a general relationship for the turbulent Prandtl number Prt for homogeneous stably stratified turbulence from the turbulent kinetic energy and scalar variance equations. A formulation for the turbulent Prandtl number, Prt, is developed in terms of a mixing length scale LM and an overturning length scale LE, the ratio of the mechanical (turbulent kinetic energy) decay time scale TL to scalar decay time scale Tp and the gradient Richardson number Ri. We show that our formulation for Prt is appropriate even for non-stationary (developing) stratified flows, since it does not include the reversible contributions in …
Identification Of Physical Changes To A Steel Frame,
2010
California Polytechnic State University, San Luis Obispo
Identification Of Physical Changes To A Steel Frame, Daniel Eric Means
Master's Theses
The thesis utilized physical testing and computer modeling to determine the feasibility of identifying a change to the mass or stiffness of a steel frame. Physical testing was performed using an accelerometer, linear shaker, and arbitrary function generator. Two methods of laboratory testing were developed: ambient vibration testing (AVT) and forced vibration testing (FVT). AVT was able to preliminarily identify the natural frequencies and mode shapes of the frame. FVT was able to precisely identify four distinct natural frequencies, mode shapes, and damping ratios. The baseline frame then underwent two physical changes: the addition of mass to its roof, and …
A Solution To Seismic Bracing Restrictions,
2010
California Polytechnic State University - San Luis Obispo
A Solution To Seismic Bracing Restrictions, John W. Lawson
Architectural Engineering
No abstract provided.
Breaking The Mould 4 : Condensation Risk Analysis – The Standards And The Issues,
2010
Technological University Dublin
Breaking The Mould 4 : Condensation Risk Analysis – The Standards And The Issues, Joseph Little
Articles
The ‘Breaking the Mould’ series of articles was written to explore the range of issues associated with upgrading single leaf walls with a focus on occupant and building health as much as energy, just as the Home Energy Saving Scheme was launched. A year on from the first article the need for greater understanding and clear guidance for the Industry is greater than ever. This is because the Government’s ‘Energy Demand Reduction Target’ (EDRT), under the 2006 EU ‘Energy Services Directive’, is bringing energy utilities (e.g. ESB, Bord Gáis) into the refurbishment market.
Estimation Of Flight Delay Costs For U.S. Domestic Air Passengers,
2010
Missouri University of Science and Technology
Estimation Of Flight Delay Costs For U.S. Domestic Air Passengers, Hojong Baik, Tao Li, Naveen K. Chintapudi
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Evaluating the economic value of flight delays has always been a keen interest of research groups as well as of federal agencies such as the U.S. Department of Transportation and FAA. However, because of the complexity of the question as well as the incompleteness of available data sets, the estimation of flight delay costs is considered a challenging task in practice. This paper presents a method for estimating domestic air passengers' delay costs incurred by flight delays in U.S. airports. a unique feature of the method is that the costs incurred by flight delays relative to the original flight schedules …
Some Comments On The Protection Of Lunar Habitats Against Damage From Meteoroid Impacts,
2010
Missouri University of Science and Technology
Some Comments On The Protection Of Lunar Habitats Against Damage From Meteoroid Impacts, William P. Schonberg, F. Schäfer, R. Putzar
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The establishment of human habitats on the Moon and on Mars will require protecting them from the hazards of near-Earth and interplanetary space. in addition to solar radiation, another hazard to be faced by these habitats is the damage that can result from the high-speed impact of a meteoroid on a critical structural component. Therefore, lunar habitats and their accompanying support facilities need to be designed with adequate levels of protection that will allow them to also withstand the damage that can result from a meteoroid impact. in this paper we discuss some approaches to shielding for lunar habitats, focusing …
Ralph Bunche Agape Neighborhood Vision Plan,
2010
Community Design Center
Ralph Bunche Agape Neighborhood Vision Plan, Community Design Center
Community Design Center Project Reports
The Ralphe Bunche Neighborhood Vision Plan provides a general design framework to spur reinvestment in this 100-year old historic African-American neighborhood in Benton, AR. The plan aggregates attainable housing (under $100,000/unit) around two neighborhood parks―one existing, and one proposed. Since the city cannot afford comprehensive street and drainage improvements to accommodate redevelopment, the proposal retrofits streets and open space with Low Impact Development (LID) landscapes to remediate urban stormwater runoff. Housing unit types between 1,000 and 1,750 square feet are amassed around these LID landscapes and amenitized with screened rooms, balconies, terraces, and multiple-height living spaces.
A Study Of The Economical Feasibility Of Installing Heating, Ventilation, And Air-Conditioning Condensate Recovery System,
2010
North Carolina Agricultural and Technical State University
A Study Of The Economical Feasibility Of Installing Heating, Ventilation, And Air-Conditioning Condensate Recovery System, Rafid M. Kully
Theses
The objective of this study is to establish a guide line or an analytical frame work to predetermine the economic benefits associated with the installation of Heating, Ventilation, and Air-Conditioning (HVAC) condensate recovery systems to capture the air-handler’s condensate water and use it as makeup water for the cooling tower. Some factors should be considered such as; the location, building operation, amount of outside air required, type of energy recovery system, and indoor conditions setup. Experimental data was used from Emory University in Georgia, where a condensate recovery system was installed and the condensate water from four air-handler units at …
Ua3/3/4 President's Office-Thompson Construction File,
2010
Western Kentucky University
Ua3/3/4 President's Office-Thompson Construction File, Wku Archives
WKU Archives Collection Inventories
Construction file regarding construction of new buildings, renovation of existing buildings and bond issues during Kelly Thompson's tenure as WKU President.
Following Industry's Leed : Municipal Adoption Of Private Green Building Standards,
2010
University of Maine School of Law
Following Industry's Leed : Municipal Adoption Of Private Green Building Standards, Sarah B. Schindler
Faculty Publications
Local governments are beginning to require new, privately constructed and funded buildings to be “green” buildings. Instead of creating their own, locally-derived definitions of green buildings, many municipalities are adopting an existing private standard created by members of the building industry: LEED (Leadership in Energy and Environmental Design). This Article explains and assesses the privately promulgated LEED standards. It argues that the translation of LEED standards, which were intended to be voluntary, into law raises several theoretical and practical problems. Specifically, private green building ordinances that rely on LEED do not ensure a reduction in the negative local environmental impacts …
Feasibility Study Of Solar Driven Underground Cooling System,
2010
University of Nebraska-Lincoln
Feasibility Study Of Solar Driven Underground Cooling System, Michel E. Shafik
Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research
In the United States the peak electrical use occurs during the summer. In addition, the building sector consumes a major portion of the annual electrical energy consumption. One of the main energy consuming components in the building sector is the Heating, Ventilation, and Air-Conditioning (HVAC) systems. This research studies the feasibility of implementing a solar driven underground cooling system that could contribute to reducing building cooling loads. The developed system consists of an Earth-to-Air Heat Exchanger (EAHE) coupled with a solar chimney that provides a natural cool draft to the test facility building at the Solar Energy Research Test Facility …
Noise Propagation Through Open Windows Of Finite Depth Into An Enclosure,
2010
University of Nebraska-Lincoln
Noise Propagation Through Open Windows Of Finite Depth Into An Enclosure, Caleb Sieck, Siu-Kit Lau
Durham School of Architectural Engineering and Construction: Faculty Publications
Predicting the insertion loss of an opening backed with an enclosed space is important for building noise control. Recent research in sound transmission through apertures of finite depth in infinite rigid baffles has included the effects of propagating and evanescent modes within the aperture in order to extend models to higher frequencies. The present study extends the model to the case of the aperture backed by a cavity as opposed to sound radiating into half-space. The role of coupling between the aperture modes, radiation modes, and cavity modes in the transmission was investigated. The results were compared to those of …
Active Noise Barrier Minimizing Pressure Gradient,
2010
University of Nebraska-Lincoln
Active Noise Barrier Minimizing Pressure Gradient, Carl Hart, Siu-Kit Lau
Durham School of Architectural Engineering and Construction: Faculty Publications
Minimization of the sound pressure field within the shadow zone of a noise barrier is achieved by reducing the pressure gradient along a line, at the top of a barrier, via active noise control. The noise control effectiveness of a barrier is increased by this strategy, especially for specific system configurations. The proposed method was evaluated by numerical simulation. Results indicate that system orientation has little effect on minimizing the pressure gradient at the top of the barrier when the error sensors are invisible to the primary noise disturbance. Highly effective control within the shadow zone and close to the …
Guide To Stones Used For Houses Of Worship In Northeastern Ohio,
2010
Cleveland Museum of Natural History
Guide To Stones Used For Houses Of Worship In Northeastern Ohio, Joseph T. Hannibal
Cleveland Memory
The purpose of this guide is to serve as an introduction and field guide to the stone used for Northeastern Ohio’s sacred landmarks. compiling this information are noted. Both exterior and interior stones are described. Locations are given so that visitors can find various interior features. Finally, interesting facts having to do with the stones are given in a remarks section and references to sources used. Original publication date 1999.
Ab-10-C037: Effects Of Noise From Building Mechanical Systems On Elementary School Student Achievement,
2010
University of Nebraska - Lincoln
Ab-10-C037: Effects Of Noise From Building Mechanical Systems On Elementary School Student Achievement, Lauren M. Ronsse, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
This project seeks to determine what relationship, if any, exists betweenbackground noise levels in elementary classrooms due to the building mechanicalsystems and student performance on achievement tests. Previous research inclassroom acoustics has clearly identified that lower background noise levelsresult in higher speech intelligibility which is crucial for the learning process;however, there is a lack of data correlating lower noise levels to improved studentachievement scores. For this study, background noise level measurements were madein 14 elementary schools in a public school system in Council Bluffs, Iowa, USA.The measurements were made in unoccupied classrooms with the central buildingmechanical systems activated. Second and …
Optimum Absorption And Aperture Parameters For Realistic Coupled Volume Spaces Determined From Computational Analysis And Subjective Testing Results,
2010
University of Nebraska-Lincoln
Optimum Absorption And Aperture Parameters For Realistic Coupled Volume Spaces Determined From Computational Analysis And Subjective Testing Results, David T. Bradley, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
This project utilizes computational modeling to study the effects of varying two architectural parameters, absorption ratio and aperture size, in a realistic coupled volume concert hall. Coupled volumes have been shown to exhibit non-exponential sound energy decay profiles, referred to as double slope effect. A number of objective metrics (T30/T15, LDT/T10, decay ratio, and ΔL) have been used to quantify the double slope effect of the profiles generated in the virtual hall. T30/T15 and LDT/T10 showed similar trends across all hall configurations, indicating decreasing double slope effect with increasing coupled volume absorption ratio for each aperture size, and producing highest …
