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  • Effect of Road Traffic on Air Pollution. Experimental Evidence from COVID-19 Lockdown

    Riccardo Rossi; Riccardo Ceccato; Massimiliano Gastaldi (MDPI AG, 2020-10-01)
    The increasing concentration of human activities in cities has been leading to a worsening in air quality, thus negatively affecting the lives and health of humans living in urban contexts. Transport is one of the main sources of pollution in such environments. Several local authorities have therefore implemented strict traffic-restriction measures. The aim of this paper is to evaluate the effectiveness and limitations of these interventions, by analyzing the relationship between traffic flows and air quality. The used dataset contains concentrations of NO, NO<sub>2</sub>, NOx and PM<sub>10</sub>, vehicle counts and meteorology, all collected during the COVID-19 lockdown in the city of Padova (Italy), in which severe limitations to contain the spread of the virus simulated long and large-scale traffic restrictions in normal conditions. In particular, statistical tests, correlation analyses and multivariate linear regression models were applied to non-rainy days in 2020, 2018 and 2017, in order to isolate the effect of traffic. Analysis indicated that vehicle flows significantly affect NO, NO<sub>2</sub>, and NOx concentrations, although no evidence of a relationship between traffic and PM<sub>10</sub> was highlighted. According to this perspective, measures to limit traffic flows seem to be effective in improving air quality only in terms of reducing nitrogen oxide.
  • Research on the Construction of Performance Indicators for the Marketing Alliance of Catering Industry and Credit Card Issuing Banks by Using the Balanced Scorecard and Fuzzy AHP

    Jui-Te Chiang; Chei-Chang Chiou; Shuh-Chyi Doong; I.-Fang Chang (MDPI AG, 2020-10-01)
    In recent years, strategic alliances have seen explosive growth in various practical fields. Various forms of strategic alliances and cooperation models have been widely used among various organizations and have received considerable attention from academic and practical circles. However, there are many factors that affect the success of marketing alliances, and the academic community has not reached a conclusion and consensus. Among them, the establishment and monitoring of a performance evaluation mechanism is one of the key points. In the past, many academic studies have devoted themselves to the establishment of performance evaluation mechanisms for many different industries, but few of them have focused on the establishment of performance evaluation mechanisms for marketing alliances between the service industry and the banking industry. The purpose of this study is to assist in the establishment of performance evaluation indicators for marketing alliance between the catering industry and credit card issuing banks by using expert Delphi, fuzzy analytic hierarchy process and balanced scorecard methods. The main result of this study is to establish five key performance evaluation indicators including customer factors, cooperative alliance factors, financial factors, learning and growth factors, and internal process factors. In terms of secondary indicators, there are seven customer sub-factors, six cooperative alliance sub-factors, five financial sub-factors, seven internal processes sub-factors, and five learning and growth sub-factors, totaling 30 sub-factors. The research results can be used as a reference for academic and practical areas.
  • The State of the Art of Use of the Concept of Ecosystem Services within Spatial Plans in the Czech Republic

    Jiří Schneider; Hana Kubíčková (MDPI AG, 2020-10-01)
    Although the use and management of ecosystem services (ES) resources and the promotion of their provision are a standard and necessary part of spatial planning tools and documents, a direct implementation of this concept is exceptional. Researchers and entire projects have so far focused mainly on identification of ecosystem services and their resources in urban environment, or on the analysis of their occurrence in spatial planning documents. That was the goal of our research as well. Spatial planning documents, systematically and methodically re-defined using ecosystem services, are what is still lacking. Our article presents the results of the analysis of the use of ecosystem services in spatial plans of five cities, regional centers in the Czech Republic. We used a text evaluation methodology focused on the explicit and implicit expression of ecosystem services. We analyzed the overall approach to the creation of spatial plans. In addition to the spatial plans, we also analyzed their assignments (SPA). We found that the current spatial planning methodology does not work with the ecosystem services approach (ESA) systemically. It focuses mainly on ES resources and implicitly envisages their provision. SPAs are a more flexible and effective tool for enforcing ESA in spatial planning than the lengthy legislative process. However, this presupposes greater knowledge of SPA among the public and decision makers.
  • Novel Sources of Variation in Grain Yield, Components and Mineral Traits Identified in Wheat Amphidiploids Derived from <i>Thinopyrum bessarabicum</i> (Savul. & Rayss) Á. Löve (Poaceae) under Saline Soils in India

    Jaswant Singh Khokhar; Sindhu Sareen; Bhudeva Singh Tyagi; Lolita Wilson; Scott Young; Julie King; Ian King; Martin R. Broadley (MDPI AG, 2020-10-01)
    Salt-affected soils constrain wheat production globally. A wild wheat species, <i>Thinopyrum bessarabicum</i> (Savul. & Rayss) Á. Löve (Poaceae)<i>,</i> and its derivatives are tolerant of high external NaCl concentrations but have not been tested yet in field conditions. The aim of this study was to study the performance of amphidiploids derived from <i>T. bessarabicum</i> for grain yield (GYD), yield components and grain mineral composition traits under normal and saline soil conditions. Field experiments were conducted at Karnal (pH<sub>(water)</sub> = 7.3) and Hisar (pH<sub>(water)</sub> = 8.3) sites in 2014–2015 and 2015–2016 in India. Grain samples were analysed using inductively coupled plasma–mass spectrometry (ICP-MS). Yield and yield component traits of amphidiploids were typically greater at Karnal than Hisar. The GYD was greater at Karnal (1.6 t ha<sup>−1</sup>) than Hisar (1.2 t ha<sup>−1</sup>) in 2014–2015. However, GYD was greater at Hisar (1.7 t ha<sup>−1</sup>) than Karnal (1.1 t ha<sup>−1</sup>) in 2015–2016. Mean grain zinc (Zn) concentration of eight amphidiploids, averaged across sites and years, varied from 36 to 43 mg kg<sup>−1</sup>. Some amphidiploids derived from <i>T. bessarabicum</i> showed greater GYD and grain Zn concentration under saline soils (Hisar) than normal soils (Karnal). These might be potential new sources for the development of salt-tolerant wheat varieties with increased grain Zn concentration under salt-affected soils.
  • COVID-19: Risk Factors and Protective Role of Resilience and Coping Strategies for Emergency Stress and Secondary Trauma in Medical Staff and Emergency Workers—An Online-Based Inquiry

    Tiziana Maiorano; Monia Vagni; Valeria Giostra; Daniela Pajardi (MDPI AG, 2020-10-01)
    The COVID-19 crisis has placed a heavy burden on medical staff and emergency workers, who may be at risk of developing psychological distress and secondary trauma. Coping and resilience to stress during a pandemic are protective factors that can mitigate the potential adverse psychological effects. Here, we investigated the direct and mediated effects of coping strategies and hardiness on secondary trauma among Italian medical staff (physicians and nurses, <i>n</i> = 140) and emergency workers (firefighters, civil protection, and ambulance personnel, <i>n</i> = 100) involved in the first phase of the pandemic. For this purpose, we collected data from participants through online questionnaires to measure emergency stress, coping strategies, hardiness, and secondary trauma. Other variables analyzed were age, sex, direct contact with COVID-19 patients, and use of personal protective equipment (PPE). We performed a correlational analysis, regressions, and a mediation analysis. The results show that nurses and physicians experienced higher levels of emergency stress than emergency workers. Direct contact with COVID-19 patients, female sex, unexpected events, and lack of PPE were risk factors for emergency stress, while resilience and coping strategies played a protective role. Mediation analysis shows that coping strategies and hardiness are protective factors and reduce the effect of stress on secondary trauma.
  • Advancement of Green Public Purchasing by Category: Do Municipality Green Purchasing Policies Have Any Role in Japan?

    Takuro Miyamoto; Naonari Yajima; Takahiro Tsukahara; Toshi H. Arimura (MDPI AG, 2020-10-01)
    The aim of this paper is to identify (1) the categories in which it is easier or more difficult for local municipalities to implement green purchasing and (2) the role and extent of green purchasing policy (GPP) in promoting green purchasing. To characterize the green purchasing potential of different categories, we examine the green purchasing rate, or the ratio of green products/services to total products/services purchased, of 21 categories of items. We employ data from a unique survey conducted by the Japanese Ministry of the Environment, which provides data on green procurement in municipalities. We observe that air conditioners suffer from low green purchasing rates, whereas most municipalities purchase green products in the paper products and stationery categories. We also examine the relationship between green purchasing rates and GPPs to identify the role and extent of GPPs. Our regression analyses reveal that the presence of a GPP is associated with higher implementation and measurement rates of green purchasing. This pattern is particularly evident for the categories in which many municipalities without GPPs purchase green products but, in most cases, do not measure their green purchasing rate.
  • Soil Contamination in Areas Impacted by Military Activities: A Critical Review

    Parya Broomandi; Mert Guney; Jong Ryeol Kim; Ferhat Karaca (MDPI AG, 2020-10-01)
    Military activities drastically affect soil properties mainly via physical/chemical disturbances during military training and warfare. The present paper aims to review (1) physical/chemical disturbances in soils following military activities, (2) approaches to characterization of contaminated military-impacted sites, and (3) advances in human health risk assessment for evaluating potential adverse impacts. A literature search mainly covering the period 2010–2020 but also including relevant selected papers published before 2010 was conducted. Selected studies (more than 160) were grouped as follows and then reviewed: ~40 on the presence of potentially toxic elements (PTEs), ~20 on energetic compounds (ECs) and chemical warfare agents (CWAs), ~40 on human health risk assessment, and generic limits/legislation, and ~60 supporting studies. Soil physical disturbances (e.g., compaction by military traffic) may drastically affect soil properties (e.g., hydraulic conductivity) causing environmental issues (e.g., increased erosion). Chemical disturbances are caused by the introduction of numerous PTEs, ECs, and CWAs and are of a wide nature. Available generic limits/legislation for these substances is limited, and their contents do not always overlap. Among numerous PTEs in military-impacted zones, Pb seems particularly problematic due to its high toxicity, abundance, and persistence. For ECs and CWAs, their highly variable physiochemical properties and biodegradability govern their specific distribution, environmental fate, and transport. Most site characterization includes proper spatial/vertical profiling, albeit without adequate consideration of contaminant speciation/fractionation. Human health risk assessment studies generally follow an agreed upon framework; however, the depth/adequacy of their use varies. Generic limits/legislation limited to a few countries do not always include all contaminants of concern, their content doesn’t overlap, and scientific basis is not always clear. Thus, a comprehensive scientific framework covering a range of contaminants is needed. Overall, contaminant speciation, fractionation, and mobility have not been fully considered in numerous studies. Chemical speciation and bioaccessibility, which directly affect the results for risk characterization, should be properly integrated into risk assessment processes for accurate results.
  • Prediction of Coding Intricacy in a Software Engineering Team through Machine Learning to Ensure Cooperative Learning and Sustainable Education

    Mehwish Naseer; Wu Zhang; Wenhao Zhu (MDPI AG, 2020-10-01)
    Coding deliverables are vital part of the software project. Teams are formed to develop a software project in a term. The performance of the team for each milestone results in the success or failure of the project. Coding intricacy is a major issue faced by students as coding is believed to be a complex field demanding skill and practice. Future education demands a smart environment for understanding students. Prediction of the coding intricacy level in teams can assist in cultivating a cooperative educational environment for sustainable education. This study proposed a boosting-based approach of a random forest (RF) algorithm of machine learning (ML) for predicting the coding intricacy level among software engineering teams. The performance of the proposed approach is compared with viable ML algorithms to evaluate its excellence. Results revealed promising results for the prediction of coding intricacy by boosting the RF algorithm as compared to bagging, J48, sequential minimal optimization (SMO), multilayer perceptron (MLP), and Naïve Bayes (NB). Logistic regression-based boosting (LogitBoost) and adaptive boosting (AdaBoost) are outperforming with 85.14% accuracy of prediction. The concerns leading towards high coding intricacy level can be resolved by discussing with peers and instructors. The proposed approach can ensure a responsible attitude among software engineering teams and drive towards fulfilling the goals of education for sustainable development by optimizing the learning environment.
  • Questionnaire for Adolescents to Evaluate Their Attitudes towards Disability

    Julián Álvarez-Delgado; Benito León-del-Barco; María- Isabel Polo-del-Río; Santiago Mendo-Lázaro (MDPI AG, 2020-10-01)
    The purpose of this article is to create and validate a brief instrument to evaluate attitudes towards persons with disabilities among the adolescent population between 12 and 16 years of age. Disability is currently understood from a contextual perspective (ecological model of disability), as the interaction of a person with her/his surroundings. As part of this interaction, the negative attitudes and expectations towards those with disabilities is still a reason for analysis, as it constitutes one of the main barriers to their inclusion in society. The evaluation of these attitudes in different age groups, using new analytical tools and instruments, is essential for the subsequent design and implementation of intervention measures in order to reverse the said attitudes and improve the collective’s place in society. In this study, there were 1282 participants, students between 12 and 16 years of age. A random selection was carried out, choosing fourteen educational centers in order to analyze the students’ attitudes towards persons with disabilities. The final result was the creation of the CBAD-12A questionnaire, made up of 12 Likert-type items, grouped into three factors: acceptance/rejection, competence/limitation, and equal opportunities. It has been demonstrated that the questionnaire possesses adequate psychometric characteristics, providing research with a new instrument to measure attitudes towards disability. The said questionnaire is useful as a diagnostic and/or predictive measure, allowing us to discover and generate interventions aimed at improving the attitudes of the adolescent population towards those with a disability<b>.</b>
  • A Research on the Relationship between Environmental Sustainability Management and Human Development

    Sue Ling Lai; Du-Nin Chen (MDPI AG, 2020-10-01)
    The study explores the relationship between environmental performance and human development. A canonical correlation analysis was conducted to discover the maximum correlation between environmental performance and human development with the optimal estimated weights for indicators as constituting the composite indices. The results show that environmental health—being the most decisive—and ecosystem vitality are important indicators for representing the environmental performance. Other important indicators, in declining order, for constituting the human development index are mean years of schooling, expected years of schooling, and life expectancy at birth, with gross national income (GNI) being the last with relatively low weight. The canonical environmental performance index has utmost effect on mean years of schooling, then expected years of schooling, with explanatory power of more than 70% for both. Effect on life expectancy at birth is more than 60%, but only less than 30% on GNI. The canonical human development index has the highest explanatory power with nearly 80% for environmental health, but only 40% for ecosystem vitality. Both canonical composite indices reach a high correlation of 91% and the mutual explanatory power is 83%, confirming that environmental performance and human development are indeed positively and highly correlated.
  • Applying the Depreciated Replacement Cost Method When Assessing the Market Value of Public Property Lacking Comparables and Income Data

    Enrico Fattinnanzi; Giovanna Acampa; Fabrizio Battisti; Orazio Campo; Fabiana Forte (MDPI AG, 2020-10-01)
    The growing interest in the enhancement, management, and sale of public building stock has increased the importance of their valuation and, as a result, the need to identify suitable methods for estimating value that take into account their peculiarities. They often boast architectural features (interfloor distance, layout, finishings, types of wiring/heating systems, etc.) that make them ‘extraordinary’ assets; in some cases, these features also endow them with monumental and/or historical importance. Thus, when valuating, it is necessary to adopt suitable methods. Where comparable examples or income-based parameters specifically concerning buildings with special features are lacking, the Depreciated Replacement Cost (DRC) method is the only system that can be used to estimate their market value. This paper aims to show how the DRC method can be applied in this specific market. The theoretical part will be coupled with a practical section where the DRC method will be used to estimate the market value of an extraordinary landmark building in Rome (Italy), the Palazzo degli Archivi di Stato (the State Archives building), in the EUR district, sold by EUR S.p.A. group (formerly known as Ente EUR) in 2015.
  • Inorganic and Organic Amendments Affect Soil Fertility, Nutrition, Photosystem II Activity, and Fruit Weight and May Enhance the Sustainability of <i>Solanum lycopersicon</i> L. (cv. ‘Mountain Fresh’) Crop

    Theocharis Chatzistathis; Vasileios Tzanakakis; Anastasia Giannakoula; Polyxeni Psoma (MDPI AG, 2020-10-01)
    One of the most important issues for modern agriculture is how to decrease fertilization rates and enhance the sustainability of crops, without decreasing yields. Two inorganic (zeolite—zeo; vermiculite—ver) amendments and their mixtures with an organic soil amendment (goat manure) (i.e., zeo + ver, manure + ver, manure + zeo) were tested, and compared to the application of a controlled release fertilizer (CRF), in order to investigate if they were able to satisfy the nutritional needs of <i>Solanum lycopersicon</i> L. plants. For this purpose, a 112-day pot experiment was performed. After zeo and manure application, exchangeable K was increased from 16.5 times to 37.5 times. At the end of the experiment, total plant biomass was significantly higher in the CRF treatment, compared to the ver treatments (ver, ver + manure). Leaf K concentration was significantly higher in the zeo treatment (5.93% dw), compared to those determined in the CRF, ver, and ver + manure. In contrast, significantly higher foliar N was found in the CRF (4.83% dw) and zeo + ver (4.24% dw) treatments, compared to manure + ver. Finally, photosystem II (PSII) activity was significantly higher in ver, and this was ascribed to the optimum foliar Mn found in this treatment (138 mg kg<sup>−1</sup> dw). It is expected that these data will provide a thorough insight towards decreasing chemical fertilization inputs and enhancing the sustainability of <i>Solanum lycopersicon</i> L. crop.
  • A Causal Model of the Sustainable Use of Resources: A Case Study on a Woodworking Process

    Tomas Macak; Jan Hron; Jaromir Stusek (MDPI AG, 2020-10-01)
    Controlling the life cycle of natural resources, from extraction within the design and the production of products to handling waste, is crucial to green growth and is a part of advancing a resource-efficient, circular economy where everything is fully utilised. One way of using resources more efficiently for a greener economy is to design a production process that takes cost and energy savings into account. From this point of view, the goal of the article is to create a causal description of sustainable woodworking—especially using renewable and non-renewable resources—in relation to changes in the concentration levels of CO<sub>2</sub> in the atmosphere. After estimating the partial parameters, this model can be used to predict or simulate different CO<sub>2</sub> concentration levels in the atmosphere—for example, based on the ratio of renewable to non-renewable sources. After a theoretical description, the subsequent practical goal is to identify the optimal settings of wood-milling process parameters for either minimising energy consumption per workpiece and unit variable costs or for maximising the overall customer benefit. For this purpose, a complete factorial design was used, and based on this, the consumption energy (direct cost) optimisation of the production process was supplemented by a profitable production calculation. The effect of reducing variability was verified using a statistical F-test. The impact of minimising energy consumption (economically expressed as the mean profit) was then validated using a Student’s <i>t</i>-test.
  • Applications of a Novel Method of Ecosystem Services Assessment into Local Policy Making in the River Blackwater Estuary, Ireland

    David Doran; Tim O’Higgins (MDPI AG, 2020-10-01)
    This article describes a method to allow for the incorporation of ecosystem services (ES) into policy, applied to the case of the River Blackwater Estuary, County Cork. The concept of ES has become mainstreamed into many country’s policies worldwide. However, practical applications of ES assessment are still far from mainstream. This paper aims to assess ES in three sites to inform site selection for conservation and enhancement measures. First, ES likely to occur in the proposed development sites were identified based on literature review, interviews and expert judgement. Second an assessment methodology involving a public survey was developed and applied. Finally, the results of the assessment were aggregated based on the use level for cultural services and the on-site area for regulating and provisioning services; the results were normalised and synthesised to produce a replicable basis for comparison across the sites. The assessment demonstrated a low-cost, practical methodology for incorporating ES into local decision-making. Regulating and cultural services were most valued at the three sites, with limited levels of provisioning services being provided. While pollination (a supporting service/intermediate regulating service) received highest overall scores, a suite of cultural services was also highly valued. The survey suggested that public engagement with ES concepts may be hampered by technical jargon, such as that employed by the Common International Classification of Ecosystem Services (CICES), and also illustrated that in this case the public engaged better with the intermediate or supporting ES of pollination than other final services that provided benefits directly to them. The implications of these findings for future applications and the assessment methodology are discussed.
  • Moisture Dry-Out Capability of Steel-Faced Mineral Wool Insulated Sandwich Panels

    Kristo Kalbe; Hubert Piikov; Targo Kalamees (MDPI AG, 2020-10-01)
    Moisture dry-out from steel-faced insulated sandwich panels has previously received little attention from researchers. This paper reports the results from laboratory tests and dynamic heat, air, and moisture transport simulations of the moisture dry-out capabilities of a steel-faced sandwich panel with a mineral wool core. Three test walls (TWs) with dimensions of 1.2 m × 0.4 m × 0.23 m were put above water containers to examine the moisture transport through the TWs. A calibrated simulation model was used to investigate the hygrothermal regime of a sandwich panel wall enclosure with different initial moisture contents and panel joint tightening tapes. The moisture dry-out capacity of the studied sandwich panels is limited (up to 2 g/day through a 30-mm-wide and 3-m-long vertical joint without tapes). When the vertical joint was covered with a vapour-permeable tape, the moisture dry-out was reduced to 1 g/day and when the joint was covered with a vapour-retarding tape, the dry-out was negligible. A very small amount of rain would be enough to raise the moisture content to water vapour saturation levels inside the sandwich wall, had the rain ingressed the enclosure. The calculated time of wetness (TOW) on the internal surface of the outer steel sheet stayed indefinitely at about 5500 h/year when vapour-retarding tapes were used and the initial relative humidity (RH) was over 80%. TOW stabilised to about 2000 h/year when a vapour-permeable tape was used regardless of the initial humidity inside the panel. A vapour-permeable tape allowed moisture dry-out but also vapour diffusion from the outside environment. To minimise the risk of moisture damage, avoiding moisture ingress during construction time or due to accidents is necessary. Additionally, a knowledge-based method is recommended to manage moisture safety during the construction process.
  • Following a Step by Step Development of a Resilience Action Plan

    Maria Adriana Cardoso; Maria João Telhado; Maria do Céu Almeida; Rita Salgado Brito; Cristina Pereira; João Barreiro; Marco Morais (MDPI AG, 2020-10-01)
    According to the United Nations, by 2030, 60% of the world’s population will live in cities, and 70% by 2050. Both consolidated and fast urbanizing areas face diverse acute shocks from natural disasters and long-term stresses, such as the effects of climate change. Therefore, there is a need for cities to implement plans for increasing resilience and improving preparedness to cope with both acute shocks and long-term stresses. Development of resilience action plans (RAP) constitutes an important process for the cities to plan their resilience enhancement in the long, medium, and short terms. These are key tools for the city, considering the associated complexity, uncertainties, data scarcity, interdependencies among urban services provided in the city, as well as involved stakeholders. Herein, a framework is presented to support city resilience action planning related to climate change through a multisector approach. The framework was applied step by step to three cities—Barcelona, Bristol, and Lisbon—and their RAPs to climate change provide roadmaps for resilience, having the urban water cycle as the core. In these plans, urban services are included, given their interactions and contributions to city’s resilience. Addressed services are water supply, wastewater, storm water, waste, electric energy, and mobility.
  • “Qualifying Peripheries” or “Repolarizing the Center”: A Comparison of Gentrification Processes in Europe

    Samaneh Sadat Nickayin; Rares Halbac-Cotoara-Zanfir; Matteo Clemente; Francesco Maria Chelli; Luca Salvati; Federico Benassi; Antonio Gimenez Morera (MDPI AG, 2020-10-01)
    Reflecting a broader form of neo-liberal urban policy underlying the progressive return of capital investment, gentrification is a key issue in urban studies. Although earlier definitions of “gentrification” focused mostly on socio-cultural processes, recent works have qualified gentrification as a mixed political–economic issue. Clarifying whether inner city gentrification should be supported, controlled, constricted, or prevented is a key debate in urban sustainability and metabolism, contributing to managing and, possibly, enhancing metropolitan resilience. To define the causes and consequences of gentrification, understanding the intrinsic linkage with different social contexts is crucial. There are no universal and comprehensive gentrification processes, displaying similarities and differences at the same time. A comparative analysis of different forms of gentrification and urban change provides basic knowledge to delineate complex, non-linear paths of socioeconomic development in cities, shedding light on the increased socioeconomic complexity and the most appropriate policies to fuel metropolitan sustainability in a broader context of global change. From this perspective, our commentary focuses on the main issues at the base of gentrification in Europe, starting from basic definitions and providing a regional vision distinguishing three “gentrification ideal-types” (northern, eastern, and Mediterranean). The implications of these different socioeconomic processes for the policy and governance of sustainable and resilient cities were discussed, evidencing new lines of investigation to frame (or re-frame) the increasing complexity of urbanization patterns and processes.
  • A Comprehensive Environmental Life Cycle Assessment of the Use of Hydrochar Pellets in Combined Heat and Power Plants

    Ali Mohammadi; G. Venkatesh; Maria Sandberg; Samieh Eskandari; Stephen Joseph; Karin Granström (MDPI AG, 2020-10-01)
    Hydrothermal carbonization (HTC) has been seen as a potentially beneficial process for converting wet biomass into value-added products. It is, however, necessary to overcome the challenges associated with handling the powdered form of hydrochar—a solid product of the HTC process—by controlling the formation of dust and facilitating smoother transportation and distribution in a potentially wide marketplace. In this paper, the authors investigate the environmental consequences of different alternatives for using hydrochar pellets produced from mixed sludges from pulp and paper mills in Sweden, using the environmental life cycle assessment (E-LCA). Two scenarios for possible end-uses of hydrochar in combined heat and power (CHP) plants as a source of energy (heat and electricity) were assessed. In these scenarios, hydrochar pellets were assumed to be combusted in CHP plants, thereby avoiding the use of combustible solid wastes (Scenario A) and coal (Scenario B), respectively, to recover energy in the form of electricity and heat. The environmental damages to Human Health, Ecosystem Quality, Climate Change, and Resources are evaluated based on 1 tonne of dry sludge as the functional unit. The results from this analysis illustrate that Scenario B, in which hydrochar replaces coal, offers the greatest reduction in all the environmental damage characterizations, except the Resources category. The displacement of energy-based coal due to hydrochar combustion contributed most significantly to the environmental damages wrought by the system—ranging from 52% in Resources to 93% in Ecosystem Quality. Overall, the results highlight that the application of hydrochar pellets for energy recovery to offset waste- and coal-based energy sources has great environmental benefits. The favorability of sludge hydrochar over solid wastes as fuel for CHP plants may be counter-intuitive at first, since HTC is an energy-intensive process, but when accounting for the necessity of dependence on imports of wastes for instance, the hydrochar pellet may well emerge as a good option for CHPs in Sweden.
  • Prediction for Overheating Risk Based on Deep Learning in a Zero Energy Building

    Yue Yuan; Jisoo Shim; Seungkeon Lee; Doosam Song; Joowook Kim (MDPI AG, 2020-10-01)
    The Passive House standard has become the standard for many countries in the construction of the Zero Energy Building (ZEB). Korea also adopted the standard and has achieved great success in building energy savings. However, some issues remain with ZEBs in Korea. Among them, this study aims to discuss overheating issues. Field measurements were carried out to analyze the overheating risk for a library built as a ZEB. A data-driven overheating risk prediction model was developed to analyze the overheating risk, requiring only a small amount of data and extending the analysis throughout the year. The main factors causing overheating during both the cooling season and the intermediate seasons are also analyzed in detail. The overheating frequency exceeded 60% of days in July and August, the midsummer season in Korea. Overheating also occurred during the intermediate seasons when air conditioners were off, such as in May and October in Korea. Overheating during the cooling season was caused mainly by unexpected increases in occupancy rate, while overheating in the mid-term was mainly due to an increase in solar irradiation. This is because domestic ZEB standards define the reinforcement of insulation and airtight performance, but there are no standards for solar insolation through windows or for internal heat generation. The results of this study suggest that a fixed performance standard for ZEBs that does not reflect the climate or cultural characteristics of the region in which a ZEB is built may not result in energy savings at the operational stage and may not guarantee the thermal comfort of occupants.
  • Psychological Safety in Aviation New Product Development Teams: Case Study of 737 MAX Airplane

    Michael Naor; Nicole Adler; Gavriel David Pinto; Alon Dumanis (MDPI AG, 2020-10-01)
    The goal of current study is to discern the antecedents of two airplane accidents involving the Boeing MAX 737. The theory of normal accidents serves as a lens to comprehend the hazard stemming from MAX design with dissonance between two critical systems: engine propulsion and flight control. Cooper’s framework further delineates lack of psychological safety during prototype development from the project’s inception along six dimensions: management/supervision, safety systems, risk, work pressure, competence, and procedures/rules. The analysis indicates dearth of leadership commitment for a safety culture under time pressure and budget constraint. Our results corroborate the paramount importance of the pilot’s extensive simulator training in order to test the interaction between the innovative Maneuvering Characteristics Augmentation System and human behavior response time. Lessons gleaned from the study include three insights. First, the importance of meticulously testing a prototype during the new product development stage and the hazard stemming from improvisation to extend the life of outdated engineering design. Second, the necessity of regulatory authorities, such as the Federal Aviation Administration, undergoing a modernization process by invigorating their ranks with data scientists attuned to 21st century skills in big data analytics. Third, FAA should diminish the delegation of self-certified permits to manufacturers.

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