ABSTRACT
In recent years, the production and consumption of fossil jet fuel have increased as a consequence of a rise in the number of passengers and goods transported by air. Despite the low demand caused by the coronavirus 2019 pandemic, an increase in the services offered by the sector is expected again. In an economic context still dependent on scarce oil, this represents a problem. There is also a problem arising from the fuel's environmental impact throughout its life cycle. Given this, a promising solution is the use of biojet fuel as renewable aviation fuel. In a circular economy framework, the use of lignocellulosic biomass in the form of sugar-rich crop residues allows the production of alcohols necessary to obtain biojet fuel. The tools provided by process intensification also make it possible to design a sustainable process with low environmental impact and capable of achieving energy savings. The goal of this work was to design an intensified process to produce biojet fuel from Mexican lignocellulosic biomass, with alcohols as intermediates. The process was modeled following a sequence of pretreatment/hydrolysis/fermentation/purification for the biomass-ethanol process, and dehydration/oligomerization/hydrogenation/distillation for ethanol-biojet process under the concept of distributed configuration. To obtain a cleaner, greener, and cheaper process, the purification zone of ethanol was intensified by employing a vapor side stream distillation column and a dividing wall column. Once designed, the entire process was optimized by employing the stochastic method of differential evolution with a tabu list to minimize the total annual cost and with the Eco-indicator-99 to evaluate the sustainability of the process. The results show that savings of 5.56% and a reduction of 1.72% in Eco-indicator-99 were achieved with a vapor side stream column in comparison with conventional distillation. On the other hand, with a dividing wall column, savings of 5.02% and reductions of 2.92% in Eco-indicator-99 were achieved. This process is capable of meeting a demand greater than 266 million liters of biojet fuel per year. However, the calculated sale price indicates that this biojet fuel still does not compete with conventional jet fuel produced in Mexico. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.
ABSTRACT
In the United States, public transit vehicles have a very low average load factor (10.1-12.4%), resulting in an excessive waste of seat capacity and poor fuel economy per passenger mile served. This problem is gravely exacerbated by the COVID-19 pandemic, which at its peak had caused more than 70% reduction in transit ridership nationwide. On the other hand, the rapid uptake of e-commerce, also accelerated by the pandemic, has put tremendous pressure on last-mile delivery. A co-modality system that integrates transit services with last-mile logistics offers a promising solution to better utilization/sharing of vehicle capacity and supporting infrastructure. Here we show such a system may be implemented based on Autonomous Modular Vehicle Technology (AMVT). At the core of AMVT is the ability to operate a fleet of modular autonomous vehicles or pods that can be moved, stationed, joined, and separated in real time. Coupling modularity with autonomy is poised to enable co-modality and beyond. We describe an AMVT bimodality system that provides integrated public transit and last-mile logistics services with a fleet of pods and discuss relevant research challenges and opportunities, research approaches, and real-world adoption issues. © 2009-2012 IEEE.
ABSTRACT
Despite its efficiency in reducing the impact of pandemics (e.g., the COVID-19), whether to introduce telemedicine as an additional way to serve chronically ill patients remains controversial for hospitals in many countries. This paper builds a stylized model to investigate a hospital's telemedicine strategy and the corresponding impacts on its operations regarding outpatient management of chronic diseases. We implement our analysis from three key concerns of the hospital in the presence of a pandemic: the differences in medical consumption and reimbursement between in-person and telemedicine modalities and the effort cost of infection reduction resulting from the pandemic. We find that in the absence of the pandemic, the hospital prefers to introduce telemedicine when the differences in medical consumption and reimbursement are both small. In the presence of the pandemic, we find that the introduction of telemedicine does not always benefit the hospital and that it is better not to introduce telemedicine in some cases since it may exacerbate the negative influence of the pandemic on the hospital's total costs. Furthermore, we surprisingly find that the hospital may set greater in-person capacity but less telemedicine capacity in response to the outbreak of the pandemic under certain conditions, which contradicts public beliefs. Finally, we show that social welfare can be improved by introducing telemedicine when the effort cost of infection reduction and the difference in reimbursement are both of moderate size. The condition under which social welfare is improved tightens with a greater difference in medical consumption. © 2021 Elsevier B.V.
ABSTRACT
The paper considers the problems of exporting organic products from Russia. It has been shown that the product of wild plants is a positive direction of export growth. About a fifth of the area of all forests of the world is located in Russia. This determines the huge potential for developing non-timber forest products—wild berries, nuts, fruits, mushrooms, birch juice, etc. Consumer societies of Centrosoyuz carry out the main collection of organic products. However, only about 20–30% of the possible volumes are of commodity value. The COVID-19 pandemic increased the demand for organic products to restore natural immunity. This fact creates good prerequisites for developing Russian exports. It is necessary to develop a concept for promoting organic products in foreign markets—support measures, compensation of costs for certification, reduction of tariffs and elimination of non-tariff restrictions, development of infrastructure, and support for promotion in foreign markets. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
Simulations incorporating economic input/output models have been applied recently to assess the extent of labor shocks from COVID 19 and their impact on supply chains at the macro level. Research is being done to extend these simulations for application to other scenarios of economic shocks beyond what was triggered through COVID related labor reductions. The problem of foreign supply chain dependency is of particular concern to localized regions as a significant portion of their economy is dependent on supplies from overseas. The extended simulation approach proposed here aims to optimize the degree to which the increased inventory supply targets allow for improved economic productivity and the ideal allocation per industry which most efficiently achieves this mitigation. This paper considers the application of the proposed simulation framework to study the regional dependence on the Asian supply chain. The case study presented in this paper demonstrates the economic insight that can be obtained through simulation analysis to support regional government decision making for the state of Alabama. © 2022 Society for Modeling & Simulation International (SCS)
ABSTRACT
Coronavirus disease 2019 (SARS-CoV-2) is an infectious disease which is caused by the severe acute respiratory syndrome (SARS) coronavirus. It was discovered in the city of Wuhan, China in late December 2019 and was later declared as a pandemic by the World Health Organization (WHO). The first case in India was reported in Kerala state when the affected person had returned from China. As a result, cases started increasing readily to all the surrounding states due to unprotected contact. In this regard, India imposed various lockdown measures to keep the spread of the disease under control by restricting people gatherings. These lockdown measures improved considerably in the air quality of the states/cities, especially in polluted industrial states, and turned out to be an important benefit. This study aims to assess and compare the impact of major air quality parameters (PM2.5, PM10, CO, NOx, Ozone) on Four major polluted Industrial states of India (Gujarat, Rajasthan, Maharashtra and Uttar Pradesh). The timeline taken for this study is taken for three phases namely: Pre-Covid (March to June of 2019);The strongly affected months of wave 1 of Covid (March to June of 2020) and wave 2 of Covid (March to June of 2021). The results highlighted the following trends during the three phases considered in this study. PM 2.5 showed a reduction of almost 35.65 percent during wave 1 and showed an increase of 7.5 percent during wave 2. PM 10 showed a reduction of almost 38.94 percent during wave 1 and showed an increase of 1.25 percent during wave 2. NOx showed a reduction of almost 54.92 percent during wave 1 and showed a reduction of 3.1 percent during wave 2. CO showed a reduction of almost 26.96 percent during wave 1 and showed a reduction of 7.38 percent during wave 2. Ozone showed a reduction of almost 16.76 percent during wave1 and showed a reduction of 38.5 percent during wave 2. © 2022 IEEE.
ABSTRACT
The effectiveness and cost implications are always top factors for policy makers while deciding upon the appropriate air pollution abatement measures. The present study aimed to understand the actual particulate matter (PM2.5 and PM10) patterns during different phases of COVID-19 lockdown periods and depict their spatial distributions covering the 36 major areas in Delhi, India. Drastic visible reduction in both the pollutants was found during lockdown phase 1 and 2. Average PM2.5 reductions of 41.97%, 39.24%, 56.04%, and 56.77% were recorded comparing lockdown and/or study period with the years 2018, 2019, 2021, and 2022, respectively. Similar average reduction of PM10 to the magnitude of 51.72%, 48.95%, 48.24%, and 49.00% was found for the referred years. However, the reduction during the before-lockdown period of 2018 and 2019 and the year 2020 did not follow such radical reduction returning the values for PM2.5 as 7.66-14.88% and that for PM10 as 12.86-20.67%. The geospatial maps generated for Delhi city followed the similar findings at macro level depicting huge reduction in PM distribution classes for the study period. For instance, the percent surface area under "moderately high"polluted due to PM2.5 came down to 0.61 during lockdown phase 2 from 13.96 during January 2020. Further, about 15 of the 36 locations reported compliance to the National Ambient Air Quality Standards (NAAQS) for either of the pollutants during the study period. Nevertheless, such reductions are short-lived because the levels went up again in the years 2021 and 2022 (except similar lockdowns) as the situation got back to normal daily life activities postlockdown. Although, lockdown may be imposed in case of severe ambient air quality in a densely populated megacity like Delhi, it remains a temporary or quick-fix solution, to be looked as a last line of defense. © 2023 Mary Ann Liebert, Inc., publishers.
ABSTRACT
An inversion system that uses a Bayesian approach to combine measurements and ADMS-Urban modelled data by adjusting individual source emissions, subject to estimated uncertainty in the measurements and emissions, has previously been applied to optimising road traffic emissions in Cambridge. In this study the system has been applied specifically to the impact of interventions, in particular the impact of COVID-19 lockdowns on NOX emissions from road traffic and other sources in London. The ADMS-Urban model was used to calculate a priori hourly NOX concentrations at 195 receptors in London representing 115 reference monitors and 80 Breathe London Network AQMesh sensors. Input data included hourly meteorological measurements from Heathrow Airport, hourly NOX concentrations from 4 rural background monitoring sites and buildings road centreline data from Ordnance Survey. A priori emissions were obtained from the London Atmospheric Emissions Inventory (LAEI) for 35 point sources, approximately 70,000 major road sources and 2,500 1km grid cells representing minor road, heating and other sources. The analysis period was 1 January 2020 to 30 April 2021. Estimated uncertainties of 4 and 12 µg/m3 were applied to reference and sensor measurements respectively, while emissions uncertainties of 100%, 50%, 20% were applied to road traffic, fuels and other emissions respectively. Road traffic emissions were assumed to have error covariance of 40% of their emissions uncertainty. Measured NOX concentrations in London reduced significantly during lockdown, with the greatest reduction (around 60%) at kerbside and roadside sites in Central London. However, poor dispersal conditions led to increased concentrations at times when restrictions were tightest. In contrast, inversion system results demonstrate that NOX emissions from road traffic dropped by around 60% in London compared with pre-lockdown levels and that this reduction occurred when the strictest lockdown measures were in force. The results also show that NOX road traffic emissions were still approximately 30% lower than pre-lockdown levels at the end of April 2021. This analysis demonstrates that lower cost sensors such as AQMesh can provide valuable insight into the effects of policy measures (in this case lockdown restrictions), if their increased uncertainty compared with reference monitors is accounted for. © British Crown Copyright (2022)
ABSTRACT
Activity restrictions implemented to control the spread of the COVID-19 virus imposed a significant effect on the air quality of cities across the world. The initiative of the World Meteorological Organisation/Global Atmospheric Watch for studying effects of the 2020 COVID-19 lockdowns on air quality has produced two sets of analysis results for cities across the world, based on observational data and modelling, respectively. The modelling study aims to evaluate the modelling tools in a regime involving significant changes of activity, and at the same provide insights on the effect of selectively reduced emissions on the chemistry and composition of urban pollutants. For most of the cities, a reduction on NOx average concentrations between 11% and 70% was calculated for the lockdown period, while PM10 was reduced by 8% up to 35% in a good agreement with measured reductions observed during the 2020 lockdown period compared to the corresponding period of 2019. Taking advantage of an operational Air Quality Modelling System, which is in continuous application in the cities of Thessaloniki and Nicosia, the contribution of sectoral emissions and the role of meteorology over the observed concentration reductions was assessed. The study reveals that in both cities, observed reductions of urban PM2.5, PM10 and NOx concentration patterns can be mainly attributed to the corresponding emissions reductions in the transport and heating sectors, while O3 is strongly affected by titration near the city centre. At the same time, meteorological patterns appear to strongly influence and even mask these effects in terms of daily averages, while the impact of imposed large-scale boundary conditions on the modelling results can also be significant. © British Crown Copyright (2022)
ABSTRACT
In a first analysis of the impacts of the reduction of anthropogenic emissions during COVID-19 lockdown over Madrid (Spain) area, we found an important NOx level reduction but the O3 and PM concentrations were increased. In this work the causes of the increments are studied using Source Apportionment Technology (SAT) included in the Comprehensive Air Quality Model with Extensions (CAMx) model. CAMx is driven by the Weather Research and Forecasting model (WRF). Two simulations are run: one simulation considers the emission reductions during the lockdown (COVID simulation) and a second simulation,” business as usual” (BAU simulation) with an emissions scenario without restrictions. Source apportionment techniques are used to identify and quantify the contributions from main pollution sources with the purpose to provide understanding on what measures should be taken to address them and this work shows the potential of these technique. SAT was used to estimate the contributions of multiple sources, and pollutant types (NOx and VOC) to ozone and particle formation in a single model run. Differences in SAT results under baseline (BAU) and COVID scenarios are used to quantify the contributions of O3 and PM2.5 reductions associated with emissions reduction in individual sectors due to the lowered human activities with a high spatial resolution (1 km). Road transport is the main emission source reduced by the lockdown and reduction in NOx emissions (59%) is higher that VOC reduction (14%). This study helps to elucidate the complex and nonlinear response of O3 and PM concentrations after a reduction of emissions mainly from the transport sector, during the COVID-19 lockdown period, that must be taken into account in the control strategies to mitigate haze pollution. The results show that despite extreme reductions in primary emissions, current air pollution cannot be fully tackled. Further consideration needs to be given to the reorganisation of energy and industrial strategy together with trans-regional joint monitoring for a comprehensive long-term air pollution plan. Source apportionment studies can support of authorities responsible to develop air quality plans. © British Crown Copyright (2022)
ABSTRACT
The lockdown in 2020 implemented due to the SARS-CoV-2 pandemic has resulted in a significant improvement in air quality at a global scale. Nationwide lockdown also considerably improved air quality at a local scale, especially in cities which were almost completely shut down during the first coronavirus wave, with nearly no activity. We tested the hypothesis that a reduction in the intensity of vehicle traffic causes a drastic decrease in urban air pollution at a local scale. We focused on two urban agglomerations, Warsaw and Cracow, in Poland. Data of the concentrations of traffic-related sources, namely NOx, PM10, and PM2.5, obtained from two air pollution monitoring stations were analyzed for the years 2020 and 2021, during which lockdown and pandemic restrictions were in effect, and for 2019, as a reference. In the years 2020–2021, the average annual concentration of NOx was decreased by ~ 19%, PM2.5 by ~ 19%, and PM10 by ~ 18% in Warsaw, while in Cracow the average annual concentration of NOx was decreased by ~ 16%, PM2.5 by ~ 22%, and PM10 by ~ 2%, compared to 2019. The contribution from traffic-related sources to the overall level of air pollution was estimated. The results indicated that ~ 30 µg/m3 of PM10, ~ 15 µg/m3 of PM2.5, and ~ 120 µg/m3 of NOx in Cracow, and ~ 20 µg/m3 of PM2.5 in Warsaw originate from moving vehicles. The nationwide lockdown allowed us to conduct this study to understand how a reduction in local traffic emissions can decrease ambient air pollution levels. © 2022, The Author(s).
ABSTRACT
The paper considers the problems of exporting organic products from Russia. It has been shown that the product of wild plants is a positive direction of export growth. About a fifth of the area of all forests of the world is located in Russia. This determines the huge potential for developing non-timber forest products—wild berries, nuts, fruits, mushrooms, birch juice, etc. Consumer societies of Centrosoyuz carry out the main collection of organic products. However, only about 20–30% of the possible volumes are of commodity value. The COVID-19 pandemic increased the demand for organic products to restore natural immunity. This fact creates good prerequisites for developing Russian exports. It is necessary to develop a concept for promoting organic products in foreign markets—support measures, compensation of costs for certification, reduction of tariffs and elimination of non-tariff restrictions, development of infrastructure, and support for promotion in foreign markets. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
The global COVID-19 pandemic has had a tremendous effect on tourism industries and allied businesses, including the hotel industry. Even though in Ukraine this business does not make a major contribution to GDP, the presence of development potential, deferred demand, and performed functions makes it an important component of Ukraine, Therefore, there is a need to assess the impact of COVID-19 on the activities of hospitality entities and justify measures to restore it. The comparison of the main indicators of the functioning of the tourism and hotel business of Ukraine before and during the pandemic period demonstrates significant reductions. However, some businesses and destinations, due to the rapid response to the new reality and the reorientation to domestic tourism, on the contrary, improved pre-epidemic indicators. The unpredictability and scale of the pandemics revealed structural problems in the sector and the need for coordinated activities to address them. The review of measures accepted by the state authorities of Ukraine to minimize the effects of COVID-19 on the tourism and hotel business by 2020 revealed their fragmentation and inconsistency. For the macroeconomic level, there offered a set of institutional and state-legal measures, and there is a partnership of stakeholders at the theme level and the micro level—the systematic operation of various innovative and digital technologies (management, sanitation, technology, and communication). The partnership activities of stakeholders contribute to the innovative recovery of this field, a special place among which is the state and legal support of tourism and business: the introduction of compensation programs for owners and employees, off tax bills, reduction of individual taxes, exemption from liability and/or enforcement contractual relations due to force majeure, and the introduction of state insurance programs to protect against the risks of pandemics. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
This paper reviewed the literature on the topics of organizational redesign, digital transformation, strategic planning, process management, administrative simplification, continuous improvement, redesign and automation, and also considered the activities developed to implement organizational redesign in the quarantine declared by the Peruvian state as a result of COVID 19, with the purpose of proposing a method for organizational redesign towards digital transformation in public entities, with a strategic and operational approach. For the implementation of the strategic approach, the institutions that functionally depend on the Ministry of Education were involved, considering the current situation in relation to the operational and territorial capacities of each region, to develop the strategic and process design. Likewise, for the implementation of the operational approach, the results of the virtual course on process management for administrative simplification 2 were used, involving several institutions that proposed and implemented improvements towards the digitization of processes, promoting digital transformation. The results of the present work consider the effective time of the administrative procedures and the cost of implementation. The effective time of the procedures was reflected in a reduction of 11% and 52% in the reduction of the cost of the procedures. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
ABSTRACT
The COVID-19 pandemic has affected virtually every human activity over the past 2 years. This paper examines how the COVID-19 pandemic interfered with the business processes in Brazil's public vocational and higher education institution. Throughout the pandemic, the Organization forced the enactment of the paper-recorded processes in a virtual implementation. To unveil how the referred paper-recorded processes subset got executed during the pandemic, we conduct a process mining on the company's information system. The process mining data shows various indications of task merging, precluding, and duration modifications. The analysis of 4231 instances of administrative processes between 2019 and 2021 showed a reduction in duration times and the number of tasks. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
ABSTRACT
This paper provides estimates of the impact of the COVID-19 outbreak on Brazilian Ethanol sales. To this end, weekly data on Ethanol sales volumes are analyzed through an ITS SARIMA model and a counterfactual analysis covering the 2019–2020. We find that the real effect of COVID-19 was a reduction above 77.97% in Brazil after the first COVID-19 death, in March 2020, and still a decrease of about 50.15% at the end of 2020. The empirical evidence confirms that the impact of the pandemic crisis, the counterfactual analysis allows estimating the real effect of COVID-19 is on average 3.76% greater than the observed against an index date reference. These results suggest that ethanol sales in Brazil were more affected than only when comparing previous results to the effects of the pandemic. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
ABSTRACT
The COVID-19 pandemic covers the whole world. It has affected global social and economic development, including the transport sector. To prevent the spread of COVID-19, individual states have introduced uncompromising and radical measures, including the closure of offices, schools, and businesses, which is also part of the traffic situation. Anti-pandemic measures in Slovakia resulted in a reduction in the mobility of the population in VHOD. In this paper, we will focus on changes in passenger mobility in the most frequently used public transport as well as on changing the preferences of passengers in public transport. The analysis will be carried out in the form of a questionnaire survey, and we will transform the results of the survey into proposals and recommendations for public transport companies. The aim of public passenger transport is to provide information with a quality transport service. Only the satisfied will use passenger public transport in large quantities. © 2022 Kaunas University of Technology. All rights reserved.
ABSTRACT
One of the most important events in recent years is the Covid-19 epidemic, which began in 2019 and continues to this day. The virus is transmitted in several ways, including medical waste (face masks, hand gloves, gowns, covers, etc.) Medical waste has increased, and the only successful way of treatment is incineration. The paper presents a design model of a mobile medical incinerator for Health Care Centres of Covid-19 in Baghdad. The clinical capacity of one centre is 50 beds and the amount of waste produced is 100 kg per day. The mobile incinerator presented has a capacity of 25 kg/h, has high efficiency, and eliminates the transmission of the virus from one area to another, by waste. The incineration process leads to the reduction of waste weight by 75% and waste volume by 95%. The paper presents a model to calculate the volume of the primary and secondary combustion chambers. The mass of gas fuel added to the burners, the volume of flue gases resulted from the medical waste combustion and the residence time of the resulting gases in the secondary combustion chamber are determined. © 2022, Politechnica University of Bucharest. All rights reserved.
ABSTRACT
The analysis of the interviews, conducted among the crewing agencies representatives, active seafarers and cadets, review of the instruments, developed by the International Maritime Organization (IMO), evaluation of the accidents' database, collected by the International Transport Workers' Federation (ITF) display fatigue as one of the leading factors greatly influencing upon the seafarers and effectiveness of their performance, especially due to the COVID-19 pandemic. Therefore, the aim of the proposed paper is to share the results of the implemented research, related with identification of cognitive and behavioral markers prioritization and inclusion of fatigue detection and decrease into Maritime Education and Training (MET) policy development aimed at improvement of seafarers' performance and safety of navigation. © 2022 IAMUC. All Rights Reserved.
ABSTRACT
Parallel Surrogate-Assisted Evolutionary Algorithms (P-SAEAs) are based on surrogate-informed reproduction operators to propose new candidates to solve computationally expensive optimization problems. Differently, Parallel Surrogate-Driven Algorithms (P-SDAs) rely on the optimization of a surrogate-informed metric of promisingness to acquire new solutions. The former are promoted to deal with moderately computationally expensive problems while the latter are put forward on very costly problems. This paper investigates the design of hybrid strategies combining the acquisition processes of both P-SAEAs and P-SDAs to retain the best of both categories of methods. The objective is to reach robustness with respect to the computational budgets and parallel scalability. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.