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Full-Text Articles in Mechanical Engineering

Effect Of A Geothermal Heat Pump System On Cooling Residential Buildings In A Hot, Dry Climate, Rania Rushdy Moussa, Ayman H. Mahmoud Dec 2023

Effect Of A Geothermal Heat Pump System On Cooling Residential Buildings In A Hot, Dry Climate, Rania Rushdy Moussa, Ayman H. Mahmoud

Architectural Engineering

ABSTRACT In the last century, electricity demand has doubled due to urban expansion, which has contributed to the formation of more urban heat islands (UHI) and the appearance of environmental hazards such as the global climate change phenomenon. Since residential buildings are considered the main electricity consumer sector in Egypt, they consume up to 42% of total energy consumption, which contributes to increasing temperatures and constitutes UHI in cities. In this context, the research aims to examine the effectiveness of using the closed vertical loop geothermal system (GSHPCV) for cooling residential buildings in a hot, dry climate, such as Cairo, …


Addressing Low Heat Pump Heating System Sales In The Uk, Ben Costelloe Jun 2023

Addressing Low Heat Pump Heating System Sales In The Uk, Ben Costelloe

Articles

The replacement of existing fossil fuel boilers with heat pumps is seen as a key measure in the decarbonisation of heating systems and addressing climate change. This policy however, is currently failing in many Western European states, particularly in the UK. The many reasons for this situation are examined. However, the age of UK housing stock and particularly the high number of dwellings built prior to the introduction of building insulation regulations in 1980, are key. To maintain the running cost of air source heat pumps competitive with those of the gas boilers they generally replace the heat pump lift …


Using Bim To Increase The Efficiency Of Energy-Driven Retrofitting Projects, Anne Grego, Shannon Chance, Barry Mcauley May 2023

Using Bim To Increase The Efficiency Of Energy-Driven Retrofitting Projects, Anne Grego, Shannon Chance, Barry Mcauley

Conference Papers

The building sector is responsible for nearly 40% of global energy consumption. Many existing buildings have poor thermal insulation and low energy performance, hindering sustainability goals. Energy-driven building retrofitting could address this issue and implementing Building Information Modelling (BIM) in retrofitting can reduce process time, costs, and waste associated with such undertakings. Yet, there is a lack of research and insufficient guidance for implementing BIM in energy-driven retrofitting. A BIM framework is presented to enhance decision-making processes during retrofitting. The aims of this study were to (1) identify BIM technologies and methodologies that could address existing barriers and improve efficiency …


Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert May 2023

Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here we present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. The storm surge depth, beach slope, and wave amplitude are varied to study the dependence of energy dissipation in the breaker on wave and bathymetric parameters. We classify wave breaker types and find a separation between …


Building Performance - Societal Drive, Programme And Symposium, Joseph Little, Patrick Daly Jan 2022

Building Performance - Societal Drive, Programme And Symposium, Joseph Little, Patrick Daly

Articles

Society is increasingly looking at the construction industry to mitigate the environmental crisis and solve the housing crisis through wholesale embrace of three broad sets of challenges. The MSc in Building Performance (Energy Efficiency in Design) (MSc BP(EED)) was created in 2017 to provide significant upskilling in the knowledge, skills, and software applications of building design professionals so that they can meet these challenges, while creating compliant, sustainable, super-low energy, new and renovated buildings. The delivery of the programme supports upskilling of employed building design professionals at Masters level, encouraging a minority to develop their capacity and interest in research …


Investigation Of The Prevalence Of Faults In The Heating, Ventilation, And Air-Conditioning Systems Of Commercial Buildings, Amir Ebrahimifakhar Nov 2021

Investigation Of The Prevalence Of Faults In The Heating, Ventilation, And Air-Conditioning Systems Of Commercial Buildings, Amir Ebrahimifakhar

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

This dissertation describes a large-scale investigation of heating, ventilation, and air-conditioning (HVAC) fault prevalence in commercial buildings in the United States. A multi-year dataset with 36,556 pieces of HVAC equipment including air handling units (AHUs), air terminal units (ATUs), and packaged rooftop units (RTUs) was analyzed to determine values for several HVAC fault prevalence metrics. The primary source of data for this study comes from three commercial fault detection and diagnostics (FDD) providers. Since each FDD provider uses different terms to refer to the same fault in an HVAC system, a mapping function was created for each FDD provider’s dataset, …


Effectiveness Of Building Systems Strategies For Mitigation Of Airborne Transmission Of Sars-Cov-2, Meng Kong, Jialei Shen, Bing Dong, Jianshun Jensen Zhang Nov 2020

Effectiveness Of Building Systems Strategies For Mitigation Of Airborne Transmission Of Sars-Cov-2, Meng Kong, Jialei Shen, Bing Dong, Jianshun Jensen Zhang

Mechanical and Aerospace Engineering - All Scholarship

Airborne transmission has been recognized as a major transmission pathway for the infectious disease COVID-19. This study investigated the effectiveness of several indoor air quality (IAQ) control strategies on the mitigation of airborne transmission of SARS-CoV-2, the virus that causes COVID-19. The well-known airborne disease infection risk model (Wells-Riley equation) was used to estimate the infection risk of the SARS-CoV-2 in seven (7) different types of spaces including conference center/ballrooms, hotel bistro//cafeteria, hotel lobby, classrooms (lecture), conference room/small classroom, hotel or cruise ship guest rooms and open plan offices. The IAQ control strategies included increased ventilation rate, improved air distribution …


Leveraging Abet Accreditation To Promote Inclusion Of Noise Control Engineering Concepts In Engineering Programs, Lily M. Wang, Bryan Beamer Nov 2020

Leveraging Abet Accreditation To Promote Inclusion Of Noise Control Engineering Concepts In Engineering Programs, Lily M. Wang, Bryan Beamer

Durham School of Architectural Engineering and Construction: Faculty Publications

Accreditation Board for Engineering and Technology, Inc. (ABET) accreditation is an internationally recognized system ensuring consistency and quality in engineering education programs. As a part of ABET accreditation, there is no set requirement for any general engineering program to include noise control engineering concepts in their curricula. However, one of the seven student outcomes that each ABET accredited engineering program must document is their students’ “ability to apply engineering design to produce solutions that meet specified needs with consideration of public health, safety, and welfare…” Controlling noise in the authors’ view is a fundamental strategy for protecting workers from occupational …


Semi Open Partitions: A Defense Strategy For Airborne Disease, Kerrie Marshall, Arik Palileo, Eric A. Schiff Oct 2020

Semi Open Partitions: A Defense Strategy For Airborne Disease, Kerrie Marshall, Arik Palileo, Eric A. Schiff

SyracuseCoE Research Brief Series

This brief summarizes research on two measures that reduce the risk of transmitting COVID-19 from an infected person to a virus-free individual. Semi-partitioned spaces can reduce airborne disease transmission when combined with a proper ventilation flow pattern in a room. With advanced displacement ventilation risk can be reduced by at least 4 times.


Quantification Of Heat Flows Through Building Entrance Doors On A Winter Day, Daeho Kang Sep 2019

Quantification Of Heat Flows Through Building Entrance Doors On A Winter Day, Daeho Kang

Publications and Research

The current methods for the prediction of the heat flow through building entrance doors have been used for years while involved with a certain degree of uncertainty. This paper describes an experimental method that accurately quantified such heat flow. The experiment monitored local environmental parameters in a college building on a cold winter day. The results of the experiment demonstrated that the experimental method is viable to accurately estimate the heat flow throughout the entrance doors and the presence of a vestibule moderated heat losses from the conditioned area. The results will be used for validating the existing methods.


Competence Of A Spray Passive Down-Draft Evaporative Cooling (Pdec) System For Space Cooling, Daeho Kang, Richard K. Strand Sep 2019

Competence Of A Spray Passive Down-Draft Evaporative Cooling (Pdec) System For Space Cooling, Daeho Kang, Richard K. Strand

Publications and Research

A spray PDEC system has been relatively less considered than other passive cooling strategies as one of the viable low-energy solutions in the cooling of buildings while having a great potential in energy savings. This study is intended to evaluate the capability of a spray PDEC system for space cooling. It comprises four simulation scenarios to see the system response and influence of indoor thermal environment when a spray PDEC system is adopted as a primary cooling system in two different climates. The simulation results show that a spray PDEC system causes a substantial variation in the indoor thermal environment …


Analysis Of The System Response Of A Spray Passive Downdraft Evaporative Cooling System, Daeho Kang, Richard K. Strand Jun 2019

Analysis Of The System Response Of A Spray Passive Downdraft Evaporative Cooling System, Daeho Kang, Richard K. Strand

Publications and Research

A spray Passive Downdraft Evaporative Cooling (PDEC) system achieves great savings for space cooling and improves indoor environmental quality by supplying a large amount of fresh outdoor air. As previous studies heavily focused on the energy saving capability of a spray PDEC system due to lack of methods for a detailed analysis, the influence of cool humid supply air from a spray PDEC system in a space in buildings has not been comprehensively studied. This study is intended to evaluate the competence of a spray PDEC system as a primary cooling system in typical spaces in a primary school building …


Ua66/1/5 Ogden College Of Science & Engineering Dean's Office Centers, Wku Archives Jan 2019

Ua66/1/5 Ogden College Of Science & Engineering Dean's Office Centers, Wku Archives

WKU Archives Collection Inventories

Records created by and about centers associated with the Dean's office in the Ogden College of Science & Engineering.


Development Of A Model To Predict The Likelihood Of Complaints Due To Assorted Tone-In-Noise Combinations, Joonhee Lee, Lily M. Wang May 2018

Development Of A Model To Predict The Likelihood Of Complaints Due To Assorted Tone-In-Noise Combinations, Joonhee Lee, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper develops a model to predict if listeners would be likely to complain due to annoyance when exposed to a certain noise signal with a prominent tone, such as those commonly produced by heating, ventilation, and air-conditioning systems. Twenty participants completed digit span tasks while exposed in a controlled lab to noise signals with differing levels of tones, ranging from 125 to 1000 Hz, and overall loudness. After completing the digit span tasks under each noise signal, from which task accuracy and speed of completion were captured, subjects were asked to rate level of annoyance and indicate the likelihood …


Performance Control Of A Spray Passive Down-Draft Evaporative Cooling System, Daeho Kang, Richard K. Strand Mar 2018

Performance Control Of A Spray Passive Down-Draft Evaporative Cooling System, Daeho Kang, Richard K. Strand

Publications and Research

A spray passive down-draft evaporative cooling system has been regarded as a low-energy cooling system that leads significant energy savings in the cooling of buildings. While the energy saving capability of the system has been proven, the ability to control a comfortable indoor environment is still inadequate due to strong climatic dependency. This study seeks viable solutions to advance the control competence of the system by mitigating critical problems of the system to be a reliable cooling application in the cooling of buildings. It proposes potential control strategies for the system and alternative operations. It develops a control algorithm for …


Case Study Of Quantifying Energy Loss Through Ceiling-Attic Recessed Lighting Fixtures Through 3d Numerical Simulation, Ri Na, Shengmao Lin, Zhigang Shen, Linxia Gu Sep 2016

Case Study Of Quantifying Energy Loss Through Ceiling-Attic Recessed Lighting Fixtures Through 3d Numerical Simulation, Ri Na, Shengmao Lin, Zhigang Shen, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Abstract Air leakage through recessed lighting fixtures has been identified as a common issue that causes extra energy consumption in residential buildings. However, few quantitative studies in this area were found. As such, a preliminary assessment of the magnitude of this type of energy loss was conducted by using three-dimensional (3D) transient computational fluid dynamics (CFD) models. A hypothetical layout of recessed lighting fixtures was designed with boundary conditions of four different seasons, which were obtained from recorded roof/attic temperature data sets. The results of the study indicate that leakage of recessed lighting fixtures could be a significant channel of …


Significance Of Parameters Affecting The Performance Of A Passive Down-Draft Evaporative Cooling (Pdec) Tower With A Spray System, Daeho Kang, Richard K. Strand Jun 2016

Significance Of Parameters Affecting The Performance Of A Passive Down-Draft Evaporative Cooling (Pdec) Tower With A Spray System, Daeho Kang, Richard K. Strand

Publications and Research

PDEC towers with spray systems are known to achieve substantial energy savings. Various parameters such as the wet-bulb depression, the tower height, and the wind speed have been known to be key factors affecting the performance of the system. To date, the significance of these parameters and other important factors have not been adequately treated in the literature. There also has been a lack of models that can successfully investigate potential benefits of the system under various conditions where this particular system could be applicable. To address these critical issues, this study performed a parametric analysis by using a FLUENT …


Effects Of Noise, Reverberation And Foreign Accent On Native And Non-Native Listeners’ Performance Of English Speech Comprehension, Zhao Ellen Peng, Lily M. Wang May 2016

Effects Of Noise, Reverberation And Foreign Accent On Native And Non-Native Listeners’ Performance Of English Speech Comprehension, Zhao Ellen Peng, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

A large number of non-native English speakers may be found in American classrooms, both as listeners and talkers. Little is known about how this population comprehends speech in realistic adverse acoustical conditions. A study was conducted to investigate the effects of background noise level (BNL), reverberation time (RT), and talker foreign accent on native and non-native listeners' speech comprehension, while controlling for English language abilities. A total of 115 adult listeners completed comprehension tasks under 15 acoustic conditions: three BNLs (RC-30, RC-40, and RC-50) and five RTs (from 0.4 to 1.2 s). Fifty-six listeners were tested with speech from native …


Design And Optimization Of Membrane-Type Acoustic Metamaterials, Matthew G. Blevins May 2016

Design And Optimization Of Membrane-Type Acoustic Metamaterials, Matthew G. Blevins

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

One of the most common problems in noise control is the attenuation of low frequency noise. Typical solutions require barriers with high density and/or thickness. Membrane-type acoustic metamaterials are a novel type of engineered material capable of high low-frequency transmission loss despite their small thickness and light weight. These materials are ideally suited to applications with strict size and weight limitations such as aircraft, automobiles, and buildings. The transmission loss profile can be manipulated by changing the micro-level substructure, stacking multiple unit cells, or by creating multi-celled arrays. To date, analysis has focused primarily on experimental studies in plane-wave tubes …


Cultural Change Through Bim: Driving Lean Transformation In Education, Avril Behan, Malachy Mathews, Kevin Furlong, Ciara Ahern, Una Beagon, Peter Brennan, Colin Conway, Lee Corcoran, Pierce Fahy, Alan Hore, Barry Mcauley, Trevor Woods Nov 2015

Cultural Change Through Bim: Driving Lean Transformation In Education, Avril Behan, Malachy Mathews, Kevin Furlong, Ciara Ahern, Una Beagon, Peter Brennan, Colin Conway, Lee Corcoran, Pierce Fahy, Alan Hore, Barry Mcauley, Trevor Woods

Conference papers

This paper presents a case study of how the adoption of BIM-based practices in the AECO industry is being reflected by cultural change in higher education in Ireland. The silo-mentality that has dominated the AECO sector for more than a century has, despite numerous reorganisations, been replicated in the structures of educational institutions, including in Dublin Institute of Technology since the inception of its founding colleges in the late 1800s. Most AECO programmes must include content that is external to the programme’s specific discipline. Through the School structures of the Institute, delivery of such content is known as "service teaching" …


Quantification And Subjective Perception Of Varying Reflection Densities In Measured Room Impulsed Responses, Hyun Hong, Lily M. Wang Jul 2015

Quantification And Subjective Perception Of Varying Reflection Densities In Measured Room Impulsed Responses, Hyun Hong, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This project focuses on quantifying and testing the subjective perception of reflection densities, or the number of reflections per second, from different room impulse responses. The widely used room acoustic metric, reverberation time, is linked to the perceived reverberation in a room. Two different rooms having the same reverberation time, though, can have different reflection densities in their room impulse responses, and this difference in reflection density may affect how listeners perceive spatial impression in rooms. To investigate how sensitive humans are to a change of reflection density, this paper first reviews assorted parameters for quantifying reflection density from measured …


Room Acoustic Effects On Speech Comprehension Of English-As-Second-Language Talkers And Listeners Versus Native-English-Speaking Talkers And Listeners, Lily M. Wang Jul 2015

Room Acoustic Effects On Speech Comprehension Of English-As-Second-Language Talkers And Listeners Versus Native-English-Speaking Talkers And Listeners, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Approximately 21% of the children in the United States school system speak a language other than English at home, but are being taught in English at school. English is additionally being used more and more often as a common language in international settings, even though participants at these international events again are not native English speakers. How do adverse room acoustic environments, including higher background noise levels and longer reverberation times, impact English-as-a-Second-Language (ESL) talkers and listeners versus native English-speaking talkers and listeners? This presentation focuses on two recent studies at the University of Nebraska that investigate how assorted room …


Assessment Of Noise-Induced Annoyance By Tones In Noise From Building Mechanical Systems, Joonhee Lee, Lily M. Wang Nov 2014

Assessment Of Noise-Induced Annoyance By Tones In Noise From Building Mechanical Systems, Joonhee Lee, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Prominent tones in noise generated by mechanical equipment in buildings can cause complaints from occupants in buildings. The ISO 1996-2 and ANSI S1.13 standards describe methodologies and metrics to quantify tonality perception, but the influence of tones in noise on human annoyance and performance is not fully understood yet. This paper investigates annoyance responses of humans while exposed to background noise with tonal components. Twenty participants completed digit span tasks while exposed to noise signals with differing levels of tones and overall loudness. Subjects were also asked to rate their annoyance after completing tasks under each noise signal. The subjective …


Effects Of Room Acoustics On Comprehension Of Foreign-Accented Speech By Native And Non-Native English-Speaking Listeners, Zhao Peng, Kristin E. Hanna, Brenna N. Boyd, Lily M. Wang Nov 2014

Effects Of Room Acoustics On Comprehension Of Foreign-Accented Speech By Native And Non-Native English-Speaking Listeners, Zhao Peng, Kristin E. Hanna, Brenna N. Boyd, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

In a previous study by the authors, reverberation time (RT) and background noise level (BNL) were both found to have negative effects on native and non-native English-speaking listeners in comprehending English speech produced by native American-English-speaking talkers. Comprehension scores were adjusted for listeners’ baseline English proficiency levels. In the present study, instead of native English-speaking talkers, two native Mandarin Chinese talkers (one male, one female) with similar English spoken proficiency were recruited to produce the same speech materials used in the previous study. A similar methodology was adopted to conduct speech comprehension tests on three groups of listeners: 1) native …


The Impact Of Building Acoustics On Speech Comprehension And Student Achievement, Lily M. Wang Nov 2014

The Impact Of Building Acoustics On Speech Comprehension And Student Achievement, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

The movement for improved classroom acoustics has primarily been grounded on studies that show how building acoustics (i.e. background noise levels and room reverberation) affect speech intelligibility, as determined by speech recognition tests. What about actual student learning, though? If students do not understand each spoken word in the classroom perfectly, can they still manage to achieve high scholastic success? This presentation will review two recent studies conducted at the University of Nebraska – Lincoln, linking classroom acoustic conditions to student learning outcomes and speech comprehension (rather than simply recognition). In the first, acoustic measurements in two public school districts …


Determining Annoyance Thresholds Of Tones In Noise, Jennifer M. Francis, Joonhee Lee, Lily M. Wang Jul 2014

Determining Annoyance Thresholds Of Tones In Noise, Jennifer M. Francis, Joonhee Lee, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Building services equipment often produces noise signatures with significant tones in them that can lead to complaints in the built environment. Previous studies have investigated prominence levels of assorted tonal frequencies, but it is still unclear what prominence of the tones across varying tonal frequencies can lead to human annoyance. This project seeks to apply two different methods towards defining annoyance thresholds of tones in noise at two tonal frequencies: 125 Hz and 500 Hz. In the first, subjects are asked to perform a task, while exposed to ten minutes of a broadband noise spectrum with a specific level of …


Stock Aggregation Model And Virtual Archetype For Large Scale Retrofit Modelling Of Local Authority Housing In Ireland, James Pittam, Paul D. O’Sullivan, Garrett O’Sullivan Jan 2014

Stock Aggregation Model And Virtual Archetype For Large Scale Retrofit Modelling Of Local Authority Housing In Ireland, James Pittam, Paul D. O’Sullivan, Garrett O’Sullivan

Conference Papers

Developing representative archetypes using a bottom up approach for stock modelling is an excellent tool for evaluating the overall performance of the building stock; however it requires detailed analysis of the various building types. Currently there is no detailed housing data base for Local Authority housing in Cork City, Ireland that catalogues the housing stocks geometric properties and thermal characteristics for each typology. This study details a methodology to catalogue the LAH stock and build a detailed housing data base. The GIS web based mapping application Google Street View is used to identify 20 house typologies across 36 LAH developments; …


Rating Low Levels Of Ambient Noise In Performing Arts Facilities, Lily M. Wang, Brent A. Kraay Jun 2013

Rating Low Levels Of Ambient Noise In Performing Arts Facilities, Lily M. Wang, Brent A. Kraay

Durham School of Architectural Engineering and Construction: Faculty Publications

Previous studies have indicated that common indoor noise rating metrics, such as Noise Criteria NC and Room Criteria RC, do not best correlate to human perceptions of annoyance and distraction in typical office environments. Based on investigations conducted at the University of Nebraska using noise levels between 30 – 60 dBA, the author has proposed that an effective indoor noise rating method should begin with a rating of level (either dBA or sones), then an assessment of spectral quality, tones, and fluctuations. How well would such a system work at very low levels of ambient noise, though, as found in …


Quantifying The Just Noticeable Difference Of Reverberation Time With Band-Limited Noise Centered Around 1000 Hz Using A Transformed Up-Down Adaptive Method, Matthew G. Blevins, Adam T. Buck, Zhao Peng, Lily M. Wang Jun 2013

Quantifying The Just Noticeable Difference Of Reverberation Time With Band-Limited Noise Centered Around 1000 Hz Using A Transformed Up-Down Adaptive Method, Matthew G. Blevins, Adam T. Buck, Zhao Peng, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This study seeks to quantify the just noticeable difference (JND) of reverberation time (RT) using band-limited noise. ISO 3382-1 lists the JND of reverberation metrics at 5% based on work by Seraphim (1958). However, others have found the JND of RT to be higher from 6% to 39%. Many of these studies utilized band-limited stimuli, e.g. speech, music motifs and bandlimited noise. A previous study by the authors conducted on 30 subjects using white noise demonstrated a JND of RT at 22%. To further verify these results and investigate potential upward frequency masking, the present study was conducted following the …


Effects Of Background Noise Alternating Between Two Levels At Varying Time Intervals On Human Perception And Performance, Andrew Hathaway, Lily M. Wang Jun 2013

Effects Of Background Noise Alternating Between Two Levels At Varying Time Intervals On Human Perception And Performance, Andrew Hathaway, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This research experiment aims to better quantify human perception and performance under increased background noise levels of varying intervals. Twenty-seven participants were tested over five 30 minute sessions where they were subjected to RC-29(H) and RC-47(RV) conditions created by broadband noise fluctuating on different time intervals. These intervals varied from two minutes to ten minutes, simulating the conditions of a noisy HVAC system turning on and off. The performance results of an arithmetic test dealing with short-term memory and a subjective questionnaire will be presented and compared to a similar test using broadband noise bursts and correlated to noise metrics …