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Research paper thumbnail of Quantifying the Enhanced Performance of Multifamily Residential Passive House over Conventional Buildings in Terms of Energy Use

Buildings, Jun 20, 2024

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Long-term application of low-cost sensors for monitoring indoor air quality and particle dynamics in a commercial building

Journal of Building Engineering, Oct 31, 2023

Research paper thumbnail of Phenomenological Understanding and Model of Fuel Bound Nitrogen Release in Coal Devolatilization and Pyrolysis

Research paper thumbnail of Effects of Pyrolysis Conditions on Coal Devolatilization

ACS Division of Fuel Chemistry, Preprints, Dec 1, 1983

The formation and evolution of PAH species in coal devolatilization is observed to be a sensitive... more The formation and evolution of PAH species in coal devolatilization is observed to be a sensitive function of the mix of molecular species present in the parent coal. Through high volatile bituminous coals and within moderate heating conditions, PAH yields increase with apparent aromaticity of the coal. Those coals having the greater aromaticity, as indicated by infrared absorption characteristics, give consistently greater tar yields than less aromatic samples. Such coals also show less variation in tar yields with changes in heating rate. For moderate heating rates to final temperatures less than 1000/sup 0/ C, the coal nitrogen evolution mirrors the parent coal evolution as char, tar or light gas species on a mass fraction basis. Heating rates of 1/sup 0/ C/sec or less are observed to lower tar yields of bituminous coals while increasing char and light gas yields. On the other hand, programmed heating rates of 10/sup 5/-10/sup 6/ /sup 0/C/sec also result in a decrease in tar yields with an increase in solid species products. A fraction of these solids appear to be soot particles. Gaseous yields of coals subjected to such high thermal fluxes show C/sub 2/H/sub 2/, CO, CH/sub 4/, HCN, C/sub 2/H/sub 4/ and polyacetylenesmore » as the predominant gas phase species.« less

Research paper thumbnail of Catalytic reaction rate enhancement at low temperatures

Research paper thumbnail of Organic Pollutant Removal System and Method

Research paper thumbnail of Inactivation of HCoV-NL63 and SARS-CoV-2 in aqueous solution by 254 nm UV-C

Journal of Photochemistry and Photobiology B: Biology

Research paper thumbnail of Detection of false data injection attacks leading to line congestions using Neural networks

Sustainable Cities and Society

Research paper thumbnail of In Situ Study of Rapid Coal Pyrolysis Using Ftir

ACS Division of Fuel Chemistry, Preprints, 1980

Research paper thumbnail of Resuspension of Bacterial Spore Particles from Duct Surfaces

Research paper thumbnail of Current Best Practices

28 A SHRA E Jou rna l ash rae.o rg A u g u s t 2 0 0 8 Ultraviolet germicidal irradiation (UVGI) ... more 28 A SHRA E Jou rna l ash rae.o rg A u g u s t 2 0 0 8 Ultraviolet germicidal irradiation (UVGI) is the use of ultraviolet (UV) energy (electromagnetic radiation with a wavelength shorter than that of visible light) to kill or inactivate viral, bacterial, and fungal species. The UV spectrum is commonly divided into UVA (wavelengths of 400 nm to 315 nm), UVB (315 nm to 280 nm), and UVC (280 nm to 200 nm). The entire UV spectrum can kill or inactivate many microorganisms, but UVC energy provides the most germicidal effect, with 265 nm being the optimum wavelength.1

Research paper thumbnail of 1 Literatur Review and Parametric Study: Indoor Particle Resuspension by Human Activity

Once an aerosol contaminant is introduced into an indoor environment, it can remain in the air, d... more Once an aerosol contaminant is introduced into an indoor environment, it can remain in the air, deposit on interior surfaces or attach to dust particles already present. Human activity, such as walking and cleaning, resuspends contaminated particles, regenerating airborne contaminants. This report is a literature review on the effects of human activity on particle re-suspension in indoor environment. A parametric investigation is also made on particle resuspension effects of potential mechanical, aerodynamic and electrostatic force components, due to human activity over the particle-containing reservoir. It is shown that combinations of mechanical-aero-electro forces from human activity, can lead to significant particle resuspension in indoor environment. Additional experimental and modeling work is recommended to quantify the influence of human activity on indoor particle resuspension. INDEX TERMS Resuspension, human activity, mechanical vibration, boundary drag force, electrostati...

Research paper thumbnail of Advancing from the current state of energy retrofits to the future state

Research paper thumbnail of Business Development in Small Commercial Building Energy Retrofit Projects—A Review on Current Industry Practices

Research paper thumbnail of UVC output dependence of low pressure mercury vapor lamps in parallel and cross flow on air temperature and velocity

Research paper thumbnail of Development of a Control Platform for a Building-Scale Hybrid Solar PV-Natural Gas Microgrid

Energies, 2019

Building-scale microgrids are a type of behind-the-meter microgrids where the building operator h... more Building-scale microgrids are a type of behind-the-meter microgrids where the building operator has control of the distributed energy resources, including, in this case, a natural gas-fired microturbine in addition to solar PV and battery energy storage systems. There is a growing trend in deploying behind-the-meter microgrids due to their benefits including the resiliency of serving critical loads, especially in regions with abundant natural gas. In order to ensure distributed energy resources are dispatched optimally for the desired mode of operation, a hierarchical control platform including a centralized controller was developed and installed. The platform includes communication and control infrastructure that interface with controllers for distributed energy resources and the building automation system of a recently built energy efficient commercial building. Based on desirable outcomes under different grid and building conditions, operational modes were defined for the microgr...

Research paper thumbnail of Uncertainty analysis of energy and economic performances of hybrid solar photovoltaic and combined cooling, heating, and power (CCHP + PV) systems using a Monte-Carlo method

Applied Energy, 2019

Impacts of uncertainties on CCHP + PV's energy and economic performance are examined. • Uncertain... more Impacts of uncertainties on CCHP + PV's energy and economic performance are examined. • Uncertainties marginally influence energy performance of CCHP + PV systems. • Uncertainties significantly influence operating costs of CCHP + PV systems. • Increasing demand charges can reduce the economic feasibility of CCHP + PV systems.

Research paper thumbnail of A statistical study on energy performance of U.S. convenience stores: Investigation of factors and bench marking on store energy use

Energy and Buildings, 2019

Research paper thumbnail of Inverse energy model development via high-dimensional data analysis and sub-metering priority in building data monitoring

Energy and Buildings, 2018

In the US, building sector consumes approximately 41% of all U.S. primary energy and 70% of all g... more In the US, building sector consumes approximately 41% of all U.S. primary energy and 70% of all generated electricity. Office building uses the largest percentage of primary and derived energy in the commercial buildings sector. Therefore, energy saving is the primary target of building renovation and equipment retrofit. To estimate energy savings after a renovation or equipment retrofit, measurement and verification (M&V) must be conducted based on energy use models or benchmark tools to track and assess savings. Although some methods and modeling tools are applied more often, there is no well-accepted model formulation methodology and some methods have high uncertainty. This paper discusses a method to formulate the energy use model as an inverse regression model via an advanced and robust high-dimensional data analysis method. According to the inverse regression model, independent variables determined to be most influential to the energy consumption should be metered prior to building retrofit or audit. To select the most influential variables, this research considers a comprehensive set of potential key variables to avoid underspecified model issue. The models established by this method are observed to have great power in predicting the building energy consumption. More importantly, through the variable selection procedure, the method identifies key variables that should be monitored to continuously improve the building energy performance. A simulation study and a case study are presented to show the effectiveness of the new approach.

Research paper thumbnail of Evaluation of a low-cost optical particle counter (Alphasense OPC-N2) for ambient air monitoring

Atmospheric Measurement Techniques Discussions, 2017

A fast growing area of research is the development of low-cost sensors for measuring air pollutan... more A fast growing area of research is the development of low-cost sensors for measuring air pollutants. The affordability and size of low-cost particle sensors makes them an attractive option for use in experiments requiring a number of instruments such as high density spatial mapping. However, for these low-cost sensors to be useful for these types of studies their accuracy and precision needs to be quantified. We evaluated the Alphasense OPC-N2, a promising low-cost miniature optical particle counter, for monitoring ambient airborne particles at typical urban background sites in the UK. The precision of the OPC-N2 was assessed by co-locating 14 instruments at a site to investigate the variation in measured concentrations. Comparison to two different reference optical particle counters as well as a TEOM-FDMS enabled the accuracy of the OPC-N2 to be evaluated. Comparison of the OPC-N2 to the reference optical instruments demonstrated reasonable agreement for the measured mass concentra...

Research paper thumbnail of Quantifying the Enhanced Performance of Multifamily Residential Passive House over Conventional Buildings in Terms of Energy Use

Buildings, Jun 20, 2024

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Long-term application of low-cost sensors for monitoring indoor air quality and particle dynamics in a commercial building

Journal of Building Engineering, Oct 31, 2023

Research paper thumbnail of Phenomenological Understanding and Model of Fuel Bound Nitrogen Release in Coal Devolatilization and Pyrolysis

Research paper thumbnail of Effects of Pyrolysis Conditions on Coal Devolatilization

ACS Division of Fuel Chemistry, Preprints, Dec 1, 1983

The formation and evolution of PAH species in coal devolatilization is observed to be a sensitive... more The formation and evolution of PAH species in coal devolatilization is observed to be a sensitive function of the mix of molecular species present in the parent coal. Through high volatile bituminous coals and within moderate heating conditions, PAH yields increase with apparent aromaticity of the coal. Those coals having the greater aromaticity, as indicated by infrared absorption characteristics, give consistently greater tar yields than less aromatic samples. Such coals also show less variation in tar yields with changes in heating rate. For moderate heating rates to final temperatures less than 1000/sup 0/ C, the coal nitrogen evolution mirrors the parent coal evolution as char, tar or light gas species on a mass fraction basis. Heating rates of 1/sup 0/ C/sec or less are observed to lower tar yields of bituminous coals while increasing char and light gas yields. On the other hand, programmed heating rates of 10/sup 5/-10/sup 6/ /sup 0/C/sec also result in a decrease in tar yields with an increase in solid species products. A fraction of these solids appear to be soot particles. Gaseous yields of coals subjected to such high thermal fluxes show C/sub 2/H/sub 2/, CO, CH/sub 4/, HCN, C/sub 2/H/sub 4/ and polyacetylenesmore » as the predominant gas phase species.« less

Research paper thumbnail of Catalytic reaction rate enhancement at low temperatures

Research paper thumbnail of Organic Pollutant Removal System and Method

Research paper thumbnail of Inactivation of HCoV-NL63 and SARS-CoV-2 in aqueous solution by 254 nm UV-C

Journal of Photochemistry and Photobiology B: Biology

Research paper thumbnail of Detection of false data injection attacks leading to line congestions using Neural networks

Sustainable Cities and Society

Research paper thumbnail of In Situ Study of Rapid Coal Pyrolysis Using Ftir

ACS Division of Fuel Chemistry, Preprints, 1980

Research paper thumbnail of Resuspension of Bacterial Spore Particles from Duct Surfaces

Research paper thumbnail of Current Best Practices

28 A SHRA E Jou rna l ash rae.o rg A u g u s t 2 0 0 8 Ultraviolet germicidal irradiation (UVGI) ... more 28 A SHRA E Jou rna l ash rae.o rg A u g u s t 2 0 0 8 Ultraviolet germicidal irradiation (UVGI) is the use of ultraviolet (UV) energy (electromagnetic radiation with a wavelength shorter than that of visible light) to kill or inactivate viral, bacterial, and fungal species. The UV spectrum is commonly divided into UVA (wavelengths of 400 nm to 315 nm), UVB (315 nm to 280 nm), and UVC (280 nm to 200 nm). The entire UV spectrum can kill or inactivate many microorganisms, but UVC energy provides the most germicidal effect, with 265 nm being the optimum wavelength.1

Research paper thumbnail of 1 Literatur Review and Parametric Study: Indoor Particle Resuspension by Human Activity

Once an aerosol contaminant is introduced into an indoor environment, it can remain in the air, d... more Once an aerosol contaminant is introduced into an indoor environment, it can remain in the air, deposit on interior surfaces or attach to dust particles already present. Human activity, such as walking and cleaning, resuspends contaminated particles, regenerating airborne contaminants. This report is a literature review on the effects of human activity on particle re-suspension in indoor environment. A parametric investigation is also made on particle resuspension effects of potential mechanical, aerodynamic and electrostatic force components, due to human activity over the particle-containing reservoir. It is shown that combinations of mechanical-aero-electro forces from human activity, can lead to significant particle resuspension in indoor environment. Additional experimental and modeling work is recommended to quantify the influence of human activity on indoor particle resuspension. INDEX TERMS Resuspension, human activity, mechanical vibration, boundary drag force, electrostati...

Research paper thumbnail of Advancing from the current state of energy retrofits to the future state

Research paper thumbnail of Business Development in Small Commercial Building Energy Retrofit Projects—A Review on Current Industry Practices

Research paper thumbnail of UVC output dependence of low pressure mercury vapor lamps in parallel and cross flow on air temperature and velocity

Research paper thumbnail of Development of a Control Platform for a Building-Scale Hybrid Solar PV-Natural Gas Microgrid

Energies, 2019

Building-scale microgrids are a type of behind-the-meter microgrids where the building operator h... more Building-scale microgrids are a type of behind-the-meter microgrids where the building operator has control of the distributed energy resources, including, in this case, a natural gas-fired microturbine in addition to solar PV and battery energy storage systems. There is a growing trend in deploying behind-the-meter microgrids due to their benefits including the resiliency of serving critical loads, especially in regions with abundant natural gas. In order to ensure distributed energy resources are dispatched optimally for the desired mode of operation, a hierarchical control platform including a centralized controller was developed and installed. The platform includes communication and control infrastructure that interface with controllers for distributed energy resources and the building automation system of a recently built energy efficient commercial building. Based on desirable outcomes under different grid and building conditions, operational modes were defined for the microgr...

Research paper thumbnail of Uncertainty analysis of energy and economic performances of hybrid solar photovoltaic and combined cooling, heating, and power (CCHP + PV) systems using a Monte-Carlo method

Applied Energy, 2019

Impacts of uncertainties on CCHP + PV's energy and economic performance are examined. • Uncertain... more Impacts of uncertainties on CCHP + PV's energy and economic performance are examined. • Uncertainties marginally influence energy performance of CCHP + PV systems. • Uncertainties significantly influence operating costs of CCHP + PV systems. • Increasing demand charges can reduce the economic feasibility of CCHP + PV systems.

Research paper thumbnail of A statistical study on energy performance of U.S. convenience stores: Investigation of factors and bench marking on store energy use

Energy and Buildings, 2019

Research paper thumbnail of Inverse energy model development via high-dimensional data analysis and sub-metering priority in building data monitoring

Energy and Buildings, 2018

In the US, building sector consumes approximately 41% of all U.S. primary energy and 70% of all g... more In the US, building sector consumes approximately 41% of all U.S. primary energy and 70% of all generated electricity. Office building uses the largest percentage of primary and derived energy in the commercial buildings sector. Therefore, energy saving is the primary target of building renovation and equipment retrofit. To estimate energy savings after a renovation or equipment retrofit, measurement and verification (M&V) must be conducted based on energy use models or benchmark tools to track and assess savings. Although some methods and modeling tools are applied more often, there is no well-accepted model formulation methodology and some methods have high uncertainty. This paper discusses a method to formulate the energy use model as an inverse regression model via an advanced and robust high-dimensional data analysis method. According to the inverse regression model, independent variables determined to be most influential to the energy consumption should be metered prior to building retrofit or audit. To select the most influential variables, this research considers a comprehensive set of potential key variables to avoid underspecified model issue. The models established by this method are observed to have great power in predicting the building energy consumption. More importantly, through the variable selection procedure, the method identifies key variables that should be monitored to continuously improve the building energy performance. A simulation study and a case study are presented to show the effectiveness of the new approach.

Research paper thumbnail of Evaluation of a low-cost optical particle counter (Alphasense OPC-N2) for ambient air monitoring

Atmospheric Measurement Techniques Discussions, 2017

A fast growing area of research is the development of low-cost sensors for measuring air pollutan... more A fast growing area of research is the development of low-cost sensors for measuring air pollutants. The affordability and size of low-cost particle sensors makes them an attractive option for use in experiments requiring a number of instruments such as high density spatial mapping. However, for these low-cost sensors to be useful for these types of studies their accuracy and precision needs to be quantified. We evaluated the Alphasense OPC-N2, a promising low-cost miniature optical particle counter, for monitoring ambient airborne particles at typical urban background sites in the UK. The precision of the OPC-N2 was assessed by co-locating 14 instruments at a site to investigate the variation in measured concentrations. Comparison to two different reference optical particle counters as well as a TEOM-FDMS enabled the accuracy of the OPC-N2 to be evaluated. Comparison of the OPC-N2 to the reference optical instruments demonstrated reasonable agreement for the measured mass concentra...