Browse
Subjects
Records with Subject: Environment
Showing records 545 to 569 of 3422. [First] Page: 1 19 20 21 22 23 24 25 26 27 Last
Utility Method as an Instrument of the Quality of Life Assessment Using the Examples of Selected European Cities
Piotr Przybyłowski, Adam Przybyłowski, Agnieszka Kałaska
April 20, 2023 (v1)
Subject: Environment
Keywords: ISO 37120 indicators, Sustainability, urban quality of life assessment, utility method
Improving quality of life still remains the main goal of strategic documents and is promoted by leaders on the global, national, regional, and local levels. Moreover, this ambitious challenge should be consistent with the principles of sustainable development, including the social, economic, and environmental aspects. The ISO 37120 indicators within the World Council on City Data (WCCD) database may be used to monitor the urban performance over time. However, the interpretation of the results is not always easy and sometimes requires a complex analysis. The aim of this paper was to investigate the possibility of illustrating in a transparent way the urban quality of life using the utility method. This study also presents that this method may facilitate making data-driven decisions on urban management, planning and investment. Thus, it may be useful for decision makers and help cities and communities of all sizes to become more sustainable, safe and resilient, prosperous, inclusive, and... [more]
Numerical and Experimental Analysis of the Effect of a Swirler with a High Swirl Number in a Biogas Combustor
Marco Osvaldo Vigueras-Zúñiga, Carlos Augusto Ramírez-Ruíz, Agustín L. Herrera-May, María Elena Tejeda-del-Cueto
April 20, 2023 (v1)
Subject: Environment
Keywords: biogas, combustion chamber, optimized swirler, pollutant emissions, strong swirl
Climate change as a worldwide phenomenon is the cause of multinational agreements such as the Kyoto Protocol and the Paris Agreement with the goal of reducing greenhouse gas emissions. Biogas is one of the most promising biofuels for the integration of clean energy sources; however, biogas has the disadvantage of a low calorific value. To overcome this problem, mechanical devices such as swirlers are implemented in combustion chambers (CCs) to increase their combustion efficiencies. A swirler induces rotation in the airstream that keeps a constant re-ignition of the air−fuel mixture in the combustion. We present the numerical modeling using computational fluid dynamics (CFD) and experimental testing of combustion with biogas in a CC, including an optimized swirler in the airstream with a swirl number (Sn) of 2.48. A turbulence model of the renormalization group (RNG) was used to analyze the turbulence. Chemistry was parameterized using the laminar flamelet model. The numerical model al... [more]
Extended Exergy Analysis (EEA) of Italy, 2013−2017
Alfonso Biondi, Enrico Sciubba
April 20, 2023 (v1)
Subject: Environment
Keywords: exergy analysis, exergy footprint, extended exergy accounting, sustainability indicators
In recent years, many studies have been published on the applications of exergy analyses to complex systems, including entire countries. Oddly, the results, although consistent, appear to lead to divergent conclusions. The underlying problem is that in a “pure” thermodynamic analysis, the so-called “externalities”, i.e., labor, capital, and environmental costs, are often neglected or only approximately included in the picture. In 1998, an extension of the theory that included the exergy content of the externalities was introduced, called “extended exergy accounting” (EEA). Its novelty consisted of the explicit inclusion of the exergy embodied in the externalities. The aim of this work is to use the results of the extended exergy accounting to obtain an indicator that can be used to assess the sustainable development of a country. First, a novel methodological approach to the theory is presented, based on the exploitation of a very large dataset obtained from several national and Europe... [more]
Possibility of Hydropower Development: A Simple-to-Use Index
Agnieszka Operacz
April 20, 2023 (v1)
Subject: Environment
Keywords: hydropower plant, hydropower potential, possibility assessment, renewable sources of energy, sustainable development
A standardized range system based on carefully selected multi-criteria is proposed in this work to assess the feasibility of hydropower implementation. A thought process has been developed as a simple-to-use and easy-to-understand methodology. Today, due to the broad concern for the natural environment, the use of renewable energy sources has become globally popular. Subsequently, such solutions as the application of renewable energy for electricity generation are often considered the most environmentally friendly installations. Unfortunately, no methodology to assess the possibility of hydropower plant realization in either scientific or industry literature has been put forward, and this constitutes a blatant failure. The proposed range system has been designed to use selected information (head, available flow, fish migration, hydrotechnical infrastructure, protected areas, environmental flow, status of surface water body), which is available through a variety of sources that are easy... [more]
Implementation of QR Code Recognition Technology Using Smartphone Camera for Indoor Positioning
Ji-In Kim, Hui-Seon Gang, Jae-Young Pyun, Goo-Rak Kwon
April 20, 2023 (v1)
Subject: Environment
Keywords: camera calibration, indoor positioning, QR code recognition
Numerous studies on positioning technology are ongoing for recognizing the positions of objects accurately. Vision-, sensor-, and signal-based technologies are combined for recognizing the positions of objects outdoors and indoors. While positioning technologies involving wireless communication based on sensors and signals are commonly used in outdoor environments, the performance becomes degraded in indoor environments. Therefore, a vision-based indoor positioning method using a QR code is proposed in this study. A user’s position is measured by determining the current position of a smartphone device accurately based on the QR code recognized with a smartphone camera. The direction, distance, and position are acquired using the relationship between the three-dimensional spatial coordinate information of the camera and the center point coordinates of a two-dimensional planar QR code obtained through camera calibration.
Directional Bending Performance of 4-Leg Jacket Substructure Supporting a 3MW Offshore Wind Turbine
Thanh-Tuan Tran, Sangkyun Kang, Jang-Ho Lee, Daeyong Lee
April 19, 2023 (v1)
Subject: Environment
Keywords: critical directionality, Design Load Cases (DLC), environmental loads, jacket substructure, modal analysis, offshore wind turbine, percentage contribution, polar diagram, Pratt bracing system
A comprehensive investigation of the directional bending performance of a 4-leg jacket substructure, supporting a 3 MW offshore wind turbine, has been carried out in this study. The jacket substructure with a Pratt bracing system which is already installed in the southwest offshore wind farm in South Korea has been chosen as a reference support structure. A numerical model of the 3MW support structure (i.e., tower, transition piece, and jacket structure) is configured, and its structural performances are evaluated under the conditions of (1) extreme environmental loads (Env), (2) critical Design Load Cases (DLCs), and (3) a total of 288 combined load cases (CBs). For the case of Env (i.e., wind, wave, and current loads), loading directions varying from 0° to 360° at intervals of 15° are considered. The DLCs are provided from the 3 MW wind turbine manufacturer, in a 6 × 12 matrix format. The selected 4-leg jacket substructure in this study showed the smallest bending stiffness at the lo... [more]
The Power of Electricity: How Effective Is It in Promoting Sustainable Development in Rural Off-Grid Islands in the Philippines?
Lorafe Lozano, Evelyn B. Taboada
April 19, 2023 (v1)
Subject: Environment
Keywords: electricity access, energy trilemma, multi-tier framework, rural electrification, sustainable development assessment
Electrification plays a crucial role in the advancement of rural communities but establishing its impact to the communities’ sustainable development remains a challenge. This paper presents a pragmatic framework for assessing how electrification affects sustainable development at the grassroots level with eight indicators in the economic, technical, social, and environmental dimensions highlighted. An exploratory factor analysis approach is applied to determine how these dimensions contribute to the community’s overall sustainable development. The framework is applied in two islands in the Philippines of less than 500 households and varying electrification levels. Results indicate that Gilutongan Island, which has less than 24-h electricity access rarely find productive uses of electricity and still make use of conventional fuels for lighting. Meanwhile, Cobrador Island, which has 24-h access see improvements in almost all aspects, although they are slightly burdened by the unaffordabi... [more]
Analyzing Characteristics of Particulate Matter Pollution in Open-Pit Coal Mines: Implications for Green Mining
Huaiting Luo, Wei Zhou, Izhar Mithal Jiskani, Zhiming Wang
April 19, 2023 (v1)
Subject: Environment
Keywords: dust pollution, environment, environmental factors, open-pit, particulate pollution, PM
The particulate pollution in the open-pit coal mines of China is particularly severe in winter. The aim of this study is to understand the pollution characteristics of particulate matter (PM) in winter and provide a basis for the prevention and control of particulate pollution. We took the problem of PM concentration at the bottom of the Haerwusu Open-pit Coal Mine (HOCM) as the research object. Dust monitoring equipment at two measurement points at different heights were positioned for continuous monitoring of the PM concentration. The data for three months were gathered. Statistical analyses were performed to analyze the variation characteristics of the PM and its relationship with meteorological factors. The results show that the average PM concentration in the study area is below the average daily limit of the China National Ambient Air Quality Standard (GB 3095-2012). However, the average concentration of PM10 exceeded the national limit in December. The order of PM concentration... [more]
The Relationship between ROP Funds and Sustainable Development—A Case Study for Poland
Łukasz Mach, Karina Bedrunka, Ireneusz Dąbrowski, Paweł Frącz
April 19, 2023 (v1)
Subject: Environment
Keywords: determinants of sustainable development, European Union funds, regional operational programmes, sustainable development
The aim of this research is to analyse the correlation between public intervention in Poland within the Regional Operational Programmes and the key macroeconomic variables for the sustainable development of regions, i.e., the labour market, with particular emphasis on the unemployment rate and the level of employment; the average monthly remuneration; the residential construction market, with particular emphasis on the number of permits issued for the construction of apartments and the number of apartments under construction. The research and the analyses carried out on the basis of the above-mentioned aspects made it possible to indicate the relations between the studied macroeconomic indicators and the EU funds spending in Polish provinces, which will enable the implementation of the sustainable development policy. The capitals used in the research process are very important components of the region’s and country’s sustainable development. In the research, a calculation methodology w... [more]
Energy Efficient Parallel Configuration Based Six Degree of Freedom Machining Bed
Zareena Kausar, Muhammad Faizan Shah, Zeeshan Masood, Hafiz Zia Ur Rehman, Sardor Khaydarov, Muhammad Tallal Saeed, Omid Razmkhah, Haseeb Yaqoob
April 19, 2023 (v1)
Subject: Environment
Keywords: computation time, control, energy consumption, Energy Efficiency, error, inverse kinematics, machining bed, parallel manipulator, sustainable development
The process of material removal from a workpiece to obtain the desired shape is termed machining. Present-day material removal technologies have high spindle speeds and thus allow quick material removal. These high-speed spindles are highly exposed to vibrations and, as a result, the accuracy of the final workpiece’s dimensions is compromised. To overcome this problem, the motion of the tool is restricted, and multiple degrees of freedom are given through the motion of the workpiece in different axes. A machining bed configured as a parallel manipulator capable of giving six degrees of freedom (DOF) to the workpiece is proposed in this regard. However, the proposed six DOF machining bed should be energy efficient to avoid an increase in machining cost. The benefit of using the proposed configuration is a reduction in dimensional error and computational time which, as a result, reduces the energy utilization, vibrations, and machining time in practice. This paper presents kinematics, dy... [more]
An Environmental and Societal Analysis of the US Electrical Energy Industry Based on the Water−Energy Nexus
Gabriela Shirkey, Megan Belongeay, Susie Wu, Xiaoguang Ma, Hassan Tavakol, Annick Anctil, Sandra Marquette-Pyatt, Rodney A. Stewart, Parikith Sinha, Richard Corkish, Jiquan Chen, Ilke Celik
April 19, 2023 (v1)
Subject: Environment
Keywords: electricity generation, employee welfare, Renewable and Sustainable Energy, water–energy nexus
To meet rising energy demands, power plant operations will expand, influencing the interactions between the water−energy nexus and society. However, a major challenge is integration of social dimensions within electricity generation. To address this, we generate a baseline dataset using US public data (2014−2019) from the Energy Information Administration and US Bureau of Labor Statistics. We identify the rate of energy consumed, CO2, SO2 and NOx emissions generated, and water used per MWh net electricity as well as employee wellbeing per unit MW capacity during electricity generation. Rates of energy consumption (MMBtu/MWh) decreased 4.9%, but water consumption and withdrawal (m3/MWh) both increased 0.93% and 0.31%, respectively. Emissions of CO2, SO2 and NOx decreased 22.64%, 75% and 25% MT/MWh, respectively. Thermoelectric cooling withdrawal and consumption is led by natural gas (50.07%, 38.31%), coal (29.61%, 25.07%), and nuclear energies (13.55%, 18.99%). Electric power generation... [more]
Research on Crop Growing Factory: Focusing on Lighting and Environmental Control with Technological Proposal
Ki-Youn Kim, Jun-Ho Huh, Han-Jong Ko
April 19, 2023 (v1)
Subject: Environment
Keywords: IoT energies, LED energies, lettuce, particulate pollutant, plant factory, smart farm, smart LED farm, smart LED farm algorithm, wavelength
Recently, the interest in the plant factory-based crop production technologies is rising following the application of the smart farm technology to the agricultural arena. A lettuce production system platform is proposed in this study considering the effects of indoor environmental conditions and artificial light sources. The spectral characteristics of a visible ray according to growth performances were analyzed first to develop a control algorithm that can stimulate the plant’s growth for the proposal. Secondly, an imaging system was designed to analyze the plant’s growth characteristics based on the images and set up the system configuration. Lastly, a crop production system was proposed by using an experimental crop production group for environmental control and monitoring.
Historical Development of Thermal Protection of Prefab Residential Housing and Its Future, an Example of the Czech Republic
Darja Kubečková, Magdaléna Vrbová
April 19, 2023 (v1)
Subject: Environment
Keywords: development, energy and thermal technique, history, interaction, legislation, prefab residential housing
The paper focuses on the development of a thermal protection and energy requirements in relation to the issue of prefab residential housing buildings and prefab housing estates while emphasizing the need for a conceptual approach and environmental considerations. The development is recapitulated with examples of compositional sets of prefab residential housing on selected sites in the Czech Republic. Based on the comparison of archival documents and results of a long-term observation of the prefab residential housing resources, it outlines the direction of further expected development of prefab housing estates within a social context. The comparison also takes into account the impact of the European Union energy strategy and the implementation of directives into the legal rules and standards of the member states. The aim of the paper is to show the negatives and positives of current political and social strategies in relation to the thermal protection of buildings, the energy managemen... [more]
A Synthetic Approach for Datacenter Power Consumption Regulation towards Specific Targets in Smart Grid Environment
Mengmeng Zhao, Xiaoying Wang
April 19, 2023 (v1)
Subject: Environment
Keywords: datacenter, demand response (DR), energy storage devices, operating cost, power regulation, smart grid
With the large-scale grid connection of renewable energy sources, the frequency stability problem of the power system has become increasingly prominent. At the same time, the development of cloud computing and its applications has attracted people’s attention to the high energy consumption characteristics of datacenters. Therefore, it was proposed to use the characteristics of the high power consumption and high flexibility of datacenters to respond to the demand response signal of the smart grid to maintain the stability of the power system. Specifically, this paper establishes a synthetic model that integrates multiple methods to precisely control and regulate the power consumption of the datacenter while minimizing the total adjustment cost. First, according to the overall characteristics of the datacenter, the power consumption models of servers and cooling systems were established. Secondly, by controlling the temperature, different kinds of energy storage devices, load characteri... [more]
A Novel Hybrid GWO-LS Estimator for Harmonic Estimation Problem in Time Varying Noisy Environment
Muhammad Abdullah, Tahir N. Malik, Ali Ahmed, Muhammad F. Nadeem, Irfan A. Khan, Rui Bo
April 19, 2023 (v1)
Subject: Environment
Keywords: electrical harmonics, grey wolf optimizer, harmonic estimation, total harmonic distortion
The power quality of the Electrical Power System (EPS) is greatly affected by electrical harmonics. Hence, accurate and proper estimation of electrical harmonics is essential to design appropriate filters for mitigation of harmonics and their associated effects on the power quality of EPS. This paper presents a novel statistical (Least Square) and meta-heuristic (Grey wolf optimizer) based hybrid technique for accurate detection and estimation of electrical harmonics with minimum computational time. The non-linear part (phase and frequency) of harmonics is estimated using GWO, while the linear part (amplitude) is estimated using the LS method. Furthermore, harmonics having transients are also estimated using proposed harmonic estimators. The effectiveness of the proposed harmonic estimator is evaluated using various case studies. Comparing the proposed approach with other harmonic estimation techniques demonstrates that it has a minimum mean square error with less complexity and better... [more]
Energy Efficiency Retrofits in Commercial Buildings: An Environmental, Financial, and Technical Analysis of Case Studies in Thailand
Christopher Charles Seeley, Shobhakar Dhakal
April 19, 2023 (v1)
Subject: Environment
Keywords: building retrofits, commercial buildings, Energy Efficiency, MAC curve, marginal abatement cost curve
In the rapidly growing economies of Southeast Asia, energy consumption and energy costs in buildings continue to increase. Over the past decade, energy consumption from the commercial building sector in Thailand has increased at an average of 4% per annum and currently represents over 30% of total electricity consumption, second only to the industrial sector. Buildings that exist today will continue to represent most of both energy and greenhouse gas (GHG) emissions from the built environment, with newly constructed buildings representing only a small additional portion. This paper analyzes the environmental, technical, and financial characteristics of energy efficiency retrofit activities in commercial buildings in Thailand through detailed case studies of forty-two projects undertaken over the past 8 years. Our findings suggest that retrofits provide significant opportunities to reduce energy use, energy costs, and GHG emissions while also validating the economic feasibility of inves... [more]
Vitalization Strategies for the Building Energy Management System (BEMS) Industry Ecosystem Based on AHP Analysis
Eunji Kim, Yoonhee Ha
April 19, 2023 (v1)
Subject: Environment
Keywords: AHP, BEMS, climate change, energy conservation, Fourth Industrial Revolution, industrial ecosystem, technology
The combination of building energy management technology and technology of the Fourth Industrial Revolution has a significant potential for reducing energy consumption and, hence, CO2 emissions. However, numerous studies have indicated barriers preventing market growth. These challenges are mainly attributed to characteristics of the ecosystem of the building energy management systems (BEMS) industry. Thisstudy aimed to identify the major challenges hindering the deployment of BEMS in combination with Fourth Industrial Revolution technologies and to derive policies conducive to the achievement of the effective BEMS industry ecosystem. An analytic hierarchy process (AHP) survey was conducted on key players in the ecosystem to achieve this. The main elements of the ecosystem, economic, institutional, technology, and social system that earned weight, followed a decreasing trend in this order. Among the sub-elements, the payback period, upfront cost, electricity pricing scheme, energy cons... [more]
Decarbonization of Residential Building Energy Supply: Impact of Cogeneration System Performance on Energy, Environment, and Economics
Praveen K. Cheekatamarla
April 19, 2023 (v1)
Subject: Environment
Keywords: building thermal load, carbon dioxide emissions, cogeneration, demand response, electrical efficiency, grid efficiency, heat pump, onsite power, primary energy, return on investment
Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a... [more]
Case Study of Pollution with Particulate Matter in Selected Locations of Polish Cities
Remigiusz Jasiński, Marta Galant-Gołębiewska, Mateusz Nowak, Monika Ginter, Paula Kurzawska, Karolina Kurtyka, Marta Maciejewska
April 19, 2023 (v1)
Subject: Environment
Keywords: particle emission sources, PM10, PM2.5, urban air quality
Despite the introduction of increasingly restrictive regulations, the air quality in Poland is still considered one of the worst in Europe. Two cities (Wroclaw and Cracow) were selected for this study, so they represent a pair of Polish cities with poor air quality, and at the same time are academic cities, popular with tourists. The article focuses on the emission of particulate matter, which is one of the most dangerous components of air pollution. The focus was on particles less than 10 µm in diameter which are most often neglected at measuring stations. We have identified the sources of particulate emissions in selected locations in Wroclaw and Cracow, and then measured particles in terms of their mass and number distribution. It was noted that the PM10 emission values obtained as a result of the measurements were different from the value specified by the Inspectorate of the Environmental Protection in Poland.
Cost and Environmental Benefits of Using Pelleted Corn Stover for Bioethanol Production
Ramsharan Pandey, Nurun Nahar, Scott W. Pryor, Ghasideh Pourhashem
April 19, 2023 (v1)
Subject: Environment
Keywords: biomass pellets, cellulosic biorefinery, Life Cycle Analysis, soaking in aqueous ammonia pretreatment, Technoeconomic Analysis
While the production costs and logistical benefits of biomass pelleting have been widely discussed in the literature, the downstream economic and environmental benefits of processing pelleted biomass have been largely neglected. To investigate those benefits, we performed a comparative techno-economic analysis and life cycle assessment of producing ethanol using loose and pelleted forms of biomass. Analyses of a 2000 metric tons (dry)/d biorefinery showed that using pelleted biomass is more economical than using loose or baled biomass. The lowest minimum ethanol selling price (MESP) for pelleted biomass was USD 0.58/gal less than the lowest MESP for loose biomass. Among all processing conditions analyzed, MESP for ethanol produced with pelleted biomass was always lower than when produced with loose biomass. Shorter pretreatment and hydrolysis times, higher pretreatment solids loadings, lower ammonia requirements, and reduced enzyme loadings were the primary factors contributing to lowe... [more]
Dynamic Prospective Average and Marginal GHG Emission Factors—Scenario-Based Method for the German Power System until 2050
Nils Seckinger, Peter Radgen
April 19, 2023 (v1)
Subject: Environment
Keywords: average emission factor, electrification, hourly emission factors, life cycle assessment, lifetime emissions, marginal emission factor, sector coupling
Due to the continuous diurnal, seasonal, and annual changes in the German power supply, prospective dynamic emission factors are needed to determine greenhouse gas (GHG) emissions from hybrid and flexible electrification measures. For the calculation of average emission factors (AEF) and marginal emission factors (MEF), detailed electricity market data are required to represent electricity trading, energy storage, and the partial load behavior of the power plant park on a unit-by-unit, hourly basis. Using two normative scenarios up to 2050, different emission factors of electricity supply with regard to the degree of decarbonization of power production were developed in a linear optimization model through different GHG emission caps (Business-As-Usual, BAU: −74%; Climate-Action-Plan, CAP: −95%). The mean hourly German AEF drops to 182 gCO2eq/kWhel (2018: 468 gCO2eq/kWhel) in the BAU scenario by the year 2050 and even to 29 gCO2eq/kWhel in the CAP scenario with 3700 almost emission-free... [more]
Co-Combustion of Biomass with Coal in Grate Water Boilers at Low Load Boiler Operation
Krzysztof Nowak, Sławomir Rabczak
April 19, 2023 (v1)
Subject: Environment
Keywords: air pollutants, Biomass, cofiring, hard coal, Polish heat market
Environmental protection, and in particular air protection against pollution, is an extremely important element of the global policy of many countries. The problem of air pollution is particularly important in Poland, where the heating market is one of the largest in Europe and is based in 74% on the use of fossil fuels, in particular hard coal. One of the technological solutions for the implementation of cleaner fuels is the co-combustion of coal and biomass. This process enables the reduction of harmful pollutants such as CO2, SO2, and can be implemented in existing boilers. Heating boilers achieve the highest design efficiency during optimal load at the level of 85−95% of nominal power. Under such conditions, heat production is most efficient. During operation, boilers are often started, extinguished or run below rated output, resulting in increased emissions. This publication presents the results of measurements of efficiency and concentrations of pollutants in the WR water boiler... [more]
Life Cycle Perspectives of Using Non-Pelleted vs. Pelleted Corn Stover in a Cellulosic Biorefinery
Nurun Nahar, Ramsharan Pandey, Ghasideh Pourhashem, David Ripplinger, Scott W. Pryor
April 19, 2023 (v1)
Subject: Environment
Keywords: biorefinery, cellulosic biomass, corn stover, densification, greenhouse gas (GHG), Life Cycle Analysis, pelleting, soaking in aqueous ammonia pretreatment, solid loadings
Cellulosic biorefineries have attracted interest due to the growing energy security and environmental concerns related to fossil fuel-based energy and chemicals. Using pelleted biomass as a biorefinery feedstock can reduce their processing inputs while improving biomass handling and transportation. However, it is still questionable whether energy and emission savings from feedstock transportation and processing can justify pelletization. A life cycle assessment approach was used to compare energy consumption and greenhouse gas (GHG) emissions from pelleted and non-pelleted corn stover as a biorefinery feedstock. Operations considered were pelleting, transportation, and soaking in aqueous ammonia (SAA) pretreatment. Despite greater GHG emissions (up to 25 times higher than the transportation) generated from the pelleting process, the model showed a significant opportunity to offset and even reduce overall GHG emissions considering the pretreatment process benefits. Our process energy an... [more]
Monitoring the Indoor Air Quality: A Case Study of Passive Cooling from Historical Hypogeal Rooms
Eleonora Laurini, Mariangela De Vita, Pierluigi De Berardinis
April 19, 2023 (v1)
Subject: Environment
Keywords: indoor air quality, natural ventilation, passive cooling, sensors, thermal comfort
Attaining a good level of internal comfort is possible by controlling various parameters. Among all, the thermo-hygrometric comfort and the indoor air quality are of fundamental importance. This research is developed with the aim of verifying the indoor air quality following the installation of a passive cooling device in a historic building located in the province of L’Aquila in the municipality of Poggio Picenze in climatic zone E. This research aims to verify the functioning of a ventilation duct installed between the hypogeal and the second level of the structure that was installed to obtain air recirculation by exploiting the inertial potential of the hypogeal room. The first phase of the research was aimed at thermo-hygrometric monitoring using sensors installed on-site and controlled remotely in order to verify the operation of the device. The second-phase object of this text was useful in investigating the acquired indoor air quality level.
Experimental Thermal Hazard Investigation of Pressure and EC/PC/EMC Mass Ratio on Electrolyte
Changcheng Liu, Kaihui Zheng, Yong Zhou, Kai Zhu, Que Huang
April 19, 2023 (v1)
Subject: Environment
Keywords: combustion characteristics, electrolyte, environmental pressure, lithium-ion battery, mass ratio
Electrolytes are involved in the thermal runaway (TR) process of cells, which is a potential hazard in lithium-ion batteries (LIBs). Therefore, the effects of different mass ratio of carbonate solvents (ethylene carbonate (EC)/propylene carbonate (PC)/ethyl methyl carbonate (EMC)) with LiBF4 and different environmental pressure on the combustion characteristics of electrolyte such as flame centerline temperature, mass loss rate (MLR) and heat release rate (HRR) were analyzed. The combustion process could be divided into four stages: ignition, stable combustion stage, stable combustion with flame color change stage and extinguishing; with the decrease of pressure, the MLR of electrolyte declined and the combustion time prolonged, while the temperature of flame centerline increased.
Showing records 545 to 569 of 3422. [First] Page: 1 19 20 21 22 23 24 25 26 27 Last
(0.04 seconds)
[Show All Subjects]

[0.05 s]