The ultimate strength of platings under compression is one of the most important factors to be addressed in the ship design.Current Rules for ship structural design generally provide explicit strength check criteria a...The ultimate strength of platings under compression is one of the most important factors to be addressed in the ship design.Current Rules for ship structural design generally provide explicit strength check criteria against buckling for simply supported and clamped platings.Nevertheless,ship platings generally exhibit an intermediate behaviour between the simple support and the clamped conditions,which implies that the torsional stiffness of supporting members should be duly considered.Hence,the main aim of this study is the development of new design formulas for the ultimate strength of platings under uniaxial compression,with short and/or long edges elastically restrained against torsion.In this respect,two benchmark studies are performed.The former is devoted to the development of new equations for the elastic buckling coefficients of platings with edges elastically restrained against torsion,based on the results of the eigenvalue buckling analysis,performed by Ansys Mechanical APDL.The latter investigates the ultimate strength of platings with elastically restrained edges,by systematically varying the plate slenderness ratio and the torsional stiffness of supporting members.Finally,the effectiveness of the new formulation is checked against a wide number of finite element(FE)simulations,to cover the entire design space of ship platings.展开更多
The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismi...The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismic response of building structures is examined. Three multi-story RC buildings, representing a very common structural typology in Italy, are used as case studies for the evaluation. They are, respectively, a rectangular plan shape, an L plan shape and a rectangular plan shape with courtyard buildings. Nonlinear static and dynamic analyses are performed by considering different seismic levels, characterized by peak ground acceleration on stiff soil equal to 0.35 g, 0.25 g and 0.15 g. Nonlinear dynamic analyses are carried out by considering twelve different earthquake directions, and rotating the direction of both the orthogonal components by 30° for each analysis(from 0° to 330°). The survey is carried out on the L plan shape structure. The results show that the angle of the seismic input motion signifi cantly infl uences the response of RC structures; the critical seismic angle, i.e., the incidence angle that produces the maximum demand, provides an increase of up to 37% in terms of both roof displacements and plastic hinge rotations.展开更多
The paper focuses on the assessment of the hull girder ultimate strength,combined with random pitting corrosion wastage,by the incremental-iterative method.After a brief review about the state of art,the local ultimat...The paper focuses on the assessment of the hull girder ultimate strength,combined with random pitting corrosion wastage,by the incremental-iterative method.After a brief review about the state of art,the local ultimate strength of pitted platings under uniaxial compression is preliminarily outlined and subsequently a closed-form design formula is endorsed in the Rule incremental-iterative method,to account for pitting corrosion wastage in the hull girder ultimate strength check.The ISSC bulk carrier is assumed as reference ship in a benchmark study,devoted to test the effectiveness of the incremental-iterative method,by a comparative analysis with a set of FE simulations,performed by Ansys Mechanical APDL.Four reference cases,with different locations of pitting corrosion wastage,are investigated focusing on nine combinations of pitting and corrosion intensity degrees.Finally,a comparative analysis between the hull girder ultimate strength,combined with pitting corrosion wastage,and the relevant values,complying with the Rule net scantling approach,is performed.Based on current results,the modified incremental-iterative method allows efficiently assessing the hull girder ultimate strength,combined with pitting corrosion wastage,so revealing useful both in the design process of new vessels and in the structural health monitoring of aged ships.展开更多
The aim of the paper is to select the most economically advantageous routes for a shipowner. The paper describes a method to select the most economically advantageous routing for oil product traders. The methodology u...The aim of the paper is to select the most economically advantageous routes for a shipowner. The paper describes a method to select the most economically advantageous routing for oil product traders. The methodology uses an expert system model integrated by MNL （multinomial logit） application. The expert system to solve routing problems in the presence of trade uncertainty. The MNL model database, on leader shipping companies of the oil derivates sector, based on choice of the route with main parameters as distance, cost of transport and terminal accessibility. The method consists in simulating routing in a discrete domain of routes served by ships calling at MED （Mediterranean） ports.展开更多
The global tectonics of Mercury is dominated by contractional features mainly represented by lobate scarps,high relief ridges,and wrinkle ridges.These structures are the expression of thrust faults and are linear or a...The global tectonics of Mercury is dominated by contractional features mainly represented by lobate scarps,high relief ridges,and wrinkle ridges.These structures are the expression of thrust faults and are linear or arcuate features widely distributed on Mercury.Locally,these structures are arranged in long systems characterized by a preferential orientation and non-random spatial distribution.In this work we identified five thrust systems,generally longer than 1000 km.They were named after the main structure or crater encompassed by the system as:Thakur,Victoria,Villa Lobos,Al-Hamadhani,and Enterprise.In order to gain clues about their formation,we dated them using the buffered crater counting technique,which can be applied to derive the ages of linear landforms such as faults,ridges and channels.To estimate the absolute age for the end of the thrust system's activity,we applied both Le Feuvre and Wieczorek Production Function and Neukum Production Functions.Moreover,to further confirm the results obtained with the buffered crater counting method,the classic stratigraphic approach has been adopted,in which a faulted and an unfaulted craters were dated for each system.The results gave consistent ages and suggested that the most movements along major structures all over Mercury most likely ended at about 3.6-3.8 Ga.This gives new clues to better understand the tectonics of the planet and,therefore,its thermal evolution.Indeed,the early occurrence of tectonic activity in the planet's history,well before than predicted by the thermophysical models,coupled with the orientation and spatial distribution of the thrust systems,suggests that other processes beside global contraction,like mantle downwelling or tidal despinning,could have contributed to the first stage of the planet's history.展开更多
The global economic crisis that blew up at the end of 2006 in the United States has had extremely negative impacts on the social, political, and economic fields. The countries operating in the most affected macro area...The global economic crisis that blew up at the end of 2006 in the United States has had extremely negative impacts on the social, political, and economic fields. The countries operating in the most affected macro areas---the United States and Europe---have put through the wringer the domestic trade relationships as well as the international ones, by injecting a chain reaction into the global economic scenario. However, there are countries that seem to be free from the economic and financial contagion overflowing over the past years, as they are moved by an ＂invincible projection toward the growth＂. The present study aims to analyze how much the main emerging market of China has been effectively involved in this vicious circle. More specifically, the study intends to propose an empirical analysis on the real connection between the macroecnnomic data and the strong structure of the Chinese publicly listed companies. This paper investigates the prediction of failure among 3,220 Chinese publicly traded companies （listed companies） during the global crisis period. By analysing the financial accounting data over the past seven years （2008 to 2014）, the emerging market score （EMS） has been adopted in order to investigate the impact of the crisis on financial distress in the main emerging market of China. The results confirm the following hypotheses： On one hand, the great majority of companies have not been suffering the downturn, since 71.93% of the entire samples present no risk of financial distress during the global crisis; on the other hand, only 6.18% have a reasonable risk of financial distress.展开更多
This paper, which is to be collocated with international research studies of the historical origins of corporate social responsibility （CSR）, deals with both the theme of CSR itself and the topics related to it thro...This paper, which is to be collocated with international research studies of the historical origins of corporate social responsibility （CSR）, deals with both the theme of CSR itself and the topics related to it through an examination of the key characteristics of the theories of the master in the field of Italian Economia Aziendale, Paolo Emilio Cassandro （1910-2004）, who wrote an impressive number of works on numerous subjects that are of notable current relevance, including the social role of business, the concept of added value, and the role of the social report in the process of providing information for external purposes. Through an analytical-descriptive approach, our work will focus in particular on certain aspects of his life and works, which show beyond doubt the great value of his contribution to the advancement, at both national and international levels, of research into CSR. The main aim of what follows is to highlight not only the innovative nature of Cassandro＇s studies of the subject when compared with other research carried out in Italy in the second half of the 20th century but also how strikingly relevant they are to CSR as a topic for international scholars today.展开更多
Aim: Exposure to the ubiquitous endocrine disrupter Bisphenol A (BPA) has been associated, in pregnancy, with low birth weight. The aim of our study is the identification of the damage caused by Bisphenol A on placent...Aim: Exposure to the ubiquitous endocrine disrupter Bisphenol A (BPA) has been associated, in pregnancy, with low birth weight. The aim of our study is the identification of the damage caused by Bisphenol A on placental tissue through the evaluation of its effects on micro-vessel density and apoptosis. Methods: After fertilization, we exposed 3 female rats to oral BPA, by means of a free access to a beverage solution containing 100 μg/L of BPA. Three female rats were used as controls. Placentas underwent histological examination and immunohistochemistry for von Willebr and factor (F-VIII) and caspase-9. Results: Sixty-seven fetuses have been produced, 30 from control rats and 37 from exposed rats. Exposed fetuses showed a lower longitudinal/transverse diameter ratio than controls (2.57 ± 0.29 vs. 2.78 ± 0.38, p < 0.05). Also, exposed fetuses showed a significant reduction in the number of placental vessels per field (124.86 ± 19.15 vs. 143.54 ± 22.09, p < 0.05). On the other hand, apoptosis is not increased by exposure, as shown by caspase-9 levels. Conclusion: Exposure to BPA during pregnancy may affect placental vascularization, and this phenomenon may explain the lower birth weight reported. However, our results do not show the increase in apoptosis observed in vitro.展开更多
The treatment of advective fluxes in high-order finite volume models is well established, but this is not the case for diffusive fluxes, due to the conflict between the discontinuous representation of the solution and...The treatment of advective fluxes in high-order finite volume models is well established, but this is not the case for diffusive fluxes, due to the conflict between the discontinuous representation of the solution and the continuous structure of analytic solutions. In this paper, a derivative reconstruction approach is proposed in the context of spectral volume methods, for the approximation of diffusive fluxes, aiming at the reconciliation of this conflict. Two different reconstructions are used for advective and diffusive fluxes： the advective reconstruction makes use of the information contained in a spectral cell, and allows the formation of discontinuities at the spectral cells boundaries; the diffusive reconstruction makes use of the information contained in contiguous spectral cells, imposing the continuity of the reconstruction at the spectral cells boundaries. The method is demonstrated by a number of numerical experiments, including the solution of shallow-water equations, complemented with the advective-diffusive transport equation of a conservative substance, showing the promising abilities of the numerical scheme proposed.展开更多
Nowadays alternative and innovative energy recovery solutions are adopted on board ships to reduce fuel consumption and harmful emissions.According to this,the present work compares the engine exhaust gas waste heat r...Nowadays alternative and innovative energy recovery solutions are adopted on board ships to reduce fuel consumption and harmful emissions.According to this,the present work compares the engine exhaust gas waste heat recovery and hybrid turbocharger technologies,which are used to improve the efficiency of a dual-fuel four-stroke(DF)marine engine.Both solutions aim to satisfy partly or entirely the ship’s electrical and/or thermal loads.For the engine exhaust gas waste heat recovery,two steam plant schemes are considered:the single steam pressure and the variable layout(single or dual steam pressure plant).In both cases,a heat recovery steam generator is used for the electric power energy generation through a steam turbine.The hybrid turbocharger is used to provide a part of the ship’s electric loads as well.The thermodynamic mathematical models of DF engines,integrated with the energy recovery systems,are developed in a Matlab-Simulink environment,allowing the comparison in terms of performance at different engine loads and fuels,which are Natural Gas(NG)and High Fuel Oil(HFO).The use of NG always involves better efficiency of the system for all the engine working conditions.It results that the highest efficiency value achievable is 56%at 50%maximum continuous rating(MCR)engine load.展开更多
Can peer-to-peer lending platforms mitigate fraudulent behaviors?Or have lending players been acting similar to free-riders?This paper constructs a new proxy to investigate lending platform misconduct and compares the...Can peer-to-peer lending platforms mitigate fraudulent behaviors?Or have lending players been acting similar to free-riders?This paper constructs a new proxy to investigate lending platform misconduct and compares the FICO score and the LendingClub credit grade.To examine whether the lack of verification by the Fintech platform affects lenders’collection performance,I explore the recovery rate(RR)of non-performing loans through a mixed-continuous model.The regression results show that the degree of prudence taken by the lending platform in the pre-screening activity negatively affects the detection of some misreporting borrowers.I also find that the Fintech platform’s missing verification information(e.g.,annual income and employment length)affects the RR of non-performing loans,thereby hampering lenders’collection performance.展开更多
The main objective of this paper is that of surveying both theoretic and econometric models exploring the existence of knowledge spillovers and quantifying firm＇s ability to identify, assimilate, and exploit existing...The main objective of this paper is that of surveying both theoretic and econometric models exploring the existence of knowledge spillovers and quantifying firm＇s ability to identify, assimilate, and exploit existing information （absorptive capacity）. In so doing, we explore different methodologies through which we may analyze the knowledge transmission： both the production function approach and the knowledge function approach. In order to construct the spillover stocks, different dimensions are considered： geographic and technological.展开更多
This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stoppi...This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stopping on the quay. Using a case study methodology and focusing on the Italian context, this exploratory study, through a qualitative approach, interviewed two main cruise terminal concessionaires and indirectly observed events planned by cruise companies in sea ports selected for outlining the role of control systems, coordination, and knowledge sharing between the players in cruise events decision-making processes. The first results show that the cruise event management processes on ship berthing and on terminal are separated. The cruise companies don＇t involve terminal concessionaires in the event organization considering them only service suppliers Also, the concessionaires conceive the events planned in the cruise infrastructures as a business unit to optimize the space use, without any forms of coordination or control with cruise companies. Knowledge sharing, coordination, and control among the two players could support the planning, and management of ＂new cruise events＂ in which the visitors may be led from the infrastructure to the ships stopped on the quay. This study offers a set of key performance indicators to support the management, control, and coordination of each inter-organizational relationship identified. Managerial implications and suggestions for improving cruise events management have been provided.展开更多
The interest in Self-Sovereign Identity(SSI)in research,industry,and governments is rapidly increasing.SSI is a paradigm where users hold their identity and credentials issued by authorized entities.SSI is revolutioni...The interest in Self-Sovereign Identity(SSI)in research,industry,and governments is rapidly increasing.SSI is a paradigm where users hold their identity and credentials issued by authorized entities.SSI is revolutionizing the concept of digital identity and enabling the definition of a trust framework wherein a service provider(verifier)validates the claims presented by a user(holder)for accessing services.However,current SSI solutions primarily focus on the presentation and verification of claims,overlooking a dual aspect:ensuring that the verifier is authorized to access the holder’s claims.Addressing this gap,this paper introduces an innovative SSI-based solution that integrates decentralized wallets with Ciphertext-Policy Attribute-Based Proxy Re-Encryption(CP-ABPRE).This combination effectively addresses the challenge of verifier authorization.Our solution,implemented on the Ethereum platform,enhances accountability by notarizing key operations through a smart contract.This paper also offers a prototype demonstrating the practicality of the proposed approach.Furthermore,it provides an extensive evaluation of the solution’s performance,emphasizing its feasibility and efficiency in real-world applications.展开更多
This work is concerned with the modelling of the interaction of fluid flow with flexibly supported rigid bodies.The fluid flow is modelled by Lattice-Boltzmann Method,coupled to a set of ordinary differential equation...This work is concerned with the modelling of the interaction of fluid flow with flexibly supported rigid bodies.The fluid flow is modelled by Lattice-Boltzmann Method,coupled to a set of ordinary differential equations describing the dynamics of the solid body in terms its elastic and damping properties.The time discretization of the body dynamics is performed via the Time Discontinuous Galerkin Method.Several numerical examples are presented and highlight the robustness and efficiency of the proposed methodology,by means of comparisons with previously published results.The examples show that the present fluid-structure method is able to capture vortexinduced oscillations of flexibly-supported rigid body.展开更多
The onset of cavitating conditions inside the nozzle of liquid injectors is known to play a major role on spray characteristics,especially on jet penetration and break-up.In this work,we present a Direct Numerical Sim...The onset of cavitating conditions inside the nozzle of liquid injectors is known to play a major role on spray characteristics,especially on jet penetration and break-up.In this work,we present a Direct Numerical Simulation(DNS)based on the Lattice Boltzmann Method(LBM)to study the fluid dynamic field inside the nozzle of a cavitating injector.The formation of the cavitating region is determined via a multi-phase approach based on the Shan-Chen equation of state.The results obtained by the LBM simulation show satisfactory agreement with both numerical and experimental data.In addition,numerical evidence of bubble break-up,following upon flow-induced cavitation,is also reported.展开更多
This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China＇s provinces. Using data provided by the Nationa...This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China＇s provinces. Using data provided by the National Bureau of Statistics of China we propose two fiscal residuum indexes for China＇s provinces over the period 1998-2004. According to Buchanan＇s original definition of fiscal residuum a first index is given by the difference between government expenditure and revenue. A second index measures enterprises＇ net fiscal benefit and is calculated as the difference between public expenditure that affect business activities and taxes paid by enterprises. We found that the first index does not significantly affect the FDI localization choice while the second one positively affects it. When looking at different subsets of provinces we found that for eastern provinces the first index has a positive and significant effect. These results confirm the role of the net fiscal benefit as a determinant of FDI inflows at the provincial level.展开更多
Photovoltaic(PV)systems are widely spread across MV and LV distribution systems and the penetration of PV generation is solidly growing.Because of the uncertain nature of the solar energy resource,PV power forecasting...Photovoltaic(PV)systems are widely spread across MV and LV distribution systems and the penetration of PV generation is solidly growing.Because of the uncertain nature of the solar energy resource,PV power forecasting models are crucial in any energy management system for smart distribution networks.Although point forecasts can suit many scopes,probabilistic forecasts add further flexibility to an energy management system and are recommended to enable a wider range of decision making and optimization strategies.This paper proposes methodology towards probabilistic PV power forecasting based on a Bayesian bootstrap quantile regression model,in which a Bayesian bootstrap is applied to estimate the parameters of a quantile regression model.A novel procedure is presented to optimize the extraction of the predictive quantiles from the bootstrapped estimation of the related coefficients,raising the predictive ability of the final forecasts.Numerical experiments based on actual data quantify an enhancement of the performance of up to 2.2%when compared to relevant benchmarks.展开更多
文摘The ultimate strength of platings under compression is one of the most important factors to be addressed in the ship design.Current Rules for ship structural design generally provide explicit strength check criteria against buckling for simply supported and clamped platings.Nevertheless,ship platings generally exhibit an intermediate behaviour between the simple support and the clamped conditions,which implies that the torsional stiffness of supporting members should be duly considered.Hence,the main aim of this study is the development of new design formulas for the ultimate strength of platings under uniaxial compression,with short and/or long edges elastically restrained against torsion.In this respect,two benchmark studies are performed.The former is devoted to the development of new equations for the elastic buckling coefficients of platings with edges elastically restrained against torsion,based on the results of the eigenvalue buckling analysis,performed by Ansys Mechanical APDL.The latter investigates the ultimate strength of platings with elastically restrained edges,by systematically varying the plate slenderness ratio and the torsional stiffness of supporting members.Finally,the effectiveness of the new formulation is checked against a wide number of finite element(FE)simulations,to cover the entire design space of ship platings.
基金partially funded by Italian Department of Civil Protection in the frame of the National ReLUIS Project 2005-2008 line 2-Theme 2
文摘The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismic response of building structures is examined. Three multi-story RC buildings, representing a very common structural typology in Italy, are used as case studies for the evaluation. They are, respectively, a rectangular plan shape, an L plan shape and a rectangular plan shape with courtyard buildings. Nonlinear static and dynamic analyses are performed by considering different seismic levels, characterized by peak ground acceleration on stiff soil equal to 0.35 g, 0.25 g and 0.15 g. Nonlinear dynamic analyses are carried out by considering twelve different earthquake directions, and rotating the direction of both the orthogonal components by 30° for each analysis(from 0° to 330°). The survey is carried out on the L plan shape structure. The results show that the angle of the seismic input motion signifi cantly infl uences the response of RC structures; the critical seismic angle, i.e., the incidence angle that produces the maximum demand, provides an increase of up to 37% in terms of both roof displacements and plastic hinge rotations.
基金Open access funding provided by Universita Parthenope di Napoli within the CRUI-CARE Agreement.
文摘The paper focuses on the assessment of the hull girder ultimate strength,combined with random pitting corrosion wastage,by the incremental-iterative method.After a brief review about the state of art,the local ultimate strength of pitted platings under uniaxial compression is preliminarily outlined and subsequently a closed-form design formula is endorsed in the Rule incremental-iterative method,to account for pitting corrosion wastage in the hull girder ultimate strength check.The ISSC bulk carrier is assumed as reference ship in a benchmark study,devoted to test the effectiveness of the incremental-iterative method,by a comparative analysis with a set of FE simulations,performed by Ansys Mechanical APDL.Four reference cases,with different locations of pitting corrosion wastage,are investigated focusing on nine combinations of pitting and corrosion intensity degrees.Finally,a comparative analysis between the hull girder ultimate strength,combined with pitting corrosion wastage,and the relevant values,complying with the Rule net scantling approach,is performed.Based on current results,the modified incremental-iterative method allows efficiently assessing the hull girder ultimate strength,combined with pitting corrosion wastage,so revealing useful both in the design process of new vessels and in the structural health monitoring of aged ships.
文摘The aim of the paper is to select the most economically advantageous routes for a shipowner. The paper describes a method to select the most economically advantageous routing for oil product traders. The methodology uses an expert system model integrated by MNL （multinomial logit） application. The expert system to solve routing problems in the presence of trade uncertainty. The MNL model database, on leader shipping companies of the oil derivates sector, based on choice of the route with main parameters as distance, cost of transport and terminal accessibility. The method consists in simulating routing in a discrete domain of routes served by ships calling at MED （Mediterranean） ports.
基金funding from the Italian Space Agency(ASI)under ASI-INAF agreement 2017-47-H.0。
文摘The global tectonics of Mercury is dominated by contractional features mainly represented by lobate scarps,high relief ridges,and wrinkle ridges.These structures are the expression of thrust faults and are linear or arcuate features widely distributed on Mercury.Locally,these structures are arranged in long systems characterized by a preferential orientation and non-random spatial distribution.In this work we identified five thrust systems,generally longer than 1000 km.They were named after the main structure or crater encompassed by the system as:Thakur,Victoria,Villa Lobos,Al-Hamadhani,and Enterprise.In order to gain clues about their formation,we dated them using the buffered crater counting technique,which can be applied to derive the ages of linear landforms such as faults,ridges and channels.To estimate the absolute age for the end of the thrust system's activity,we applied both Le Feuvre and Wieczorek Production Function and Neukum Production Functions.Moreover,to further confirm the results obtained with the buffered crater counting method,the classic stratigraphic approach has been adopted,in which a faulted and an unfaulted craters were dated for each system.The results gave consistent ages and suggested that the most movements along major structures all over Mercury most likely ended at about 3.6-3.8 Ga.This gives new clues to better understand the tectonics of the planet and,therefore,its thermal evolution.Indeed,the early occurrence of tectonic activity in the planet's history,well before than predicted by the thermophysical models,coupled with the orientation and spatial distribution of the thrust systems,suggests that other processes beside global contraction,like mantle downwelling or tidal despinning,could have contributed to the first stage of the planet's history.
文摘The global economic crisis that blew up at the end of 2006 in the United States has had extremely negative impacts on the social, political, and economic fields. The countries operating in the most affected macro areas---the United States and Europe---have put through the wringer the domestic trade relationships as well as the international ones, by injecting a chain reaction into the global economic scenario. However, there are countries that seem to be free from the economic and financial contagion overflowing over the past years, as they are moved by an ＂invincible projection toward the growth＂. The present study aims to analyze how much the main emerging market of China has been effectively involved in this vicious circle. More specifically, the study intends to propose an empirical analysis on the real connection between the macroecnnomic data and the strong structure of the Chinese publicly listed companies. This paper investigates the prediction of failure among 3,220 Chinese publicly traded companies （listed companies） during the global crisis period. By analysing the financial accounting data over the past seven years （2008 to 2014）, the emerging market score （EMS） has been adopted in order to investigate the impact of the crisis on financial distress in the main emerging market of China. The results confirm the following hypotheses： On one hand, the great majority of companies have not been suffering the downturn, since 71.93% of the entire samples present no risk of financial distress during the global crisis; on the other hand, only 6.18% have a reasonable risk of financial distress.
文摘This paper, which is to be collocated with international research studies of the historical origins of corporate social responsibility （CSR）, deals with both the theme of CSR itself and the topics related to it through an examination of the key characteristics of the theories of the master in the field of Italian Economia Aziendale, Paolo Emilio Cassandro （1910-2004）, who wrote an impressive number of works on numerous subjects that are of notable current relevance, including the social role of business, the concept of added value, and the role of the social report in the process of providing information for external purposes. Through an analytical-descriptive approach, our work will focus in particular on certain aspects of his life and works, which show beyond doubt the great value of his contribution to the advancement, at both national and international levels, of research into CSR. The main aim of what follows is to highlight not only the innovative nature of Cassandro＇s studies of the subject when compared with other research carried out in Italy in the second half of the 20th century but also how strikingly relevant they are to CSR as a topic for international scholars today.
文摘Aim: Exposure to the ubiquitous endocrine disrupter Bisphenol A (BPA) has been associated, in pregnancy, with low birth weight. The aim of our study is the identification of the damage caused by Bisphenol A on placental tissue through the evaluation of its effects on micro-vessel density and apoptosis. Methods: After fertilization, we exposed 3 female rats to oral BPA, by means of a free access to a beverage solution containing 100 μg/L of BPA. Three female rats were used as controls. Placentas underwent histological examination and immunohistochemistry for von Willebr and factor (F-VIII) and caspase-9. Results: Sixty-seven fetuses have been produced, 30 from control rats and 37 from exposed rats. Exposed fetuses showed a lower longitudinal/transverse diameter ratio than controls (2.57 ± 0.29 vs. 2.78 ± 0.38, p < 0.05). Also, exposed fetuses showed a significant reduction in the number of placental vessels per field (124.86 ± 19.15 vs. 143.54 ± 22.09, p < 0.05). On the other hand, apoptosis is not increased by exposure, as shown by caspase-9 levels. Conclusion: Exposure to BPA during pregnancy may affect placental vascularization, and this phenomenon may explain the lower birth weight reported. However, our results do not show the increase in apoptosis observed in vitro.
文摘The treatment of advective fluxes in high-order finite volume models is well established, but this is not the case for diffusive fluxes, due to the conflict between the discontinuous representation of the solution and the continuous structure of analytic solutions. In this paper, a derivative reconstruction approach is proposed in the context of spectral volume methods, for the approximation of diffusive fluxes, aiming at the reconciliation of this conflict. Two different reconstructions are used for advective and diffusive fluxes： the advective reconstruction makes use of the information contained in a spectral cell, and allows the formation of discontinuities at the spectral cells boundaries; the diffusive reconstruction makes use of the information contained in contiguous spectral cells, imposing the continuity of the reconstruction at the spectral cells boundaries. The method is demonstrated by a number of numerical experiments, including the solution of shallow-water equations, complemented with the advective-diffusive transport equation of a conservative substance, showing the promising abilities of the numerical scheme proposed.
文摘Nowadays alternative and innovative energy recovery solutions are adopted on board ships to reduce fuel consumption and harmful emissions.According to this,the present work compares the engine exhaust gas waste heat recovery and hybrid turbocharger technologies,which are used to improve the efficiency of a dual-fuel four-stroke(DF)marine engine.Both solutions aim to satisfy partly or entirely the ship’s electrical and/or thermal loads.For the engine exhaust gas waste heat recovery,two steam plant schemes are considered:the single steam pressure and the variable layout(single or dual steam pressure plant).In both cases,a heat recovery steam generator is used for the electric power energy generation through a steam turbine.The hybrid turbocharger is used to provide a part of the ship’s electric loads as well.The thermodynamic mathematical models of DF engines,integrated with the energy recovery systems,are developed in a Matlab-Simulink environment,allowing the comparison in terms of performance at different engine loads and fuels,which are Natural Gas(NG)and High Fuel Oil(HFO).The use of NG always involves better efficiency of the system for all the engine working conditions.It results that the highest efficiency value achievable is 56%at 50%maximum continuous rating(MCR)engine load.
文摘Can peer-to-peer lending platforms mitigate fraudulent behaviors?Or have lending players been acting similar to free-riders?This paper constructs a new proxy to investigate lending platform misconduct and compares the FICO score and the LendingClub credit grade.To examine whether the lack of verification by the Fintech platform affects lenders’collection performance,I explore the recovery rate(RR)of non-performing loans through a mixed-continuous model.The regression results show that the degree of prudence taken by the lending platform in the pre-screening activity negatively affects the detection of some misreporting borrowers.I also find that the Fintech platform’s missing verification information(e.g.,annual income and employment length)affects the RR of non-performing loans,thereby hampering lenders’collection performance.
文摘The main objective of this paper is that of surveying both theoretic and econometric models exploring the existence of knowledge spillovers and quantifying firm＇s ability to identify, assimilate, and exploit existing information （absorptive capacity）. In so doing, we explore different methodologies through which we may analyze the knowledge transmission： both the production function approach and the knowledge function approach. In order to construct the spillover stocks, different dimensions are considered： geographic and technological.
文摘This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stopping on the quay. Using a case study methodology and focusing on the Italian context, this exploratory study, through a qualitative approach, interviewed two main cruise terminal concessionaires and indirectly observed events planned by cruise companies in sea ports selected for outlining the role of control systems, coordination, and knowledge sharing between the players in cruise events decision-making processes. The first results show that the cruise event management processes on ship berthing and on terminal are separated. The cruise companies don＇t involve terminal concessionaires in the event organization considering them only service suppliers Also, the concessionaires conceive the events planned in the cruise infrastructures as a business unit to optimize the space use, without any forms of coordination or control with cruise companies. Knowledge sharing, coordination, and control among the two players could support the planning, and management of ＂new cruise events＂ in which the visitors may be led from the infrastructure to the ships stopped on the quay. This study offers a set of key performance indicators to support the management, control, and coordination of each inter-organizational relationship identified. Managerial implications and suggestions for improving cruise events management have been provided.
基金supported by the project STRIDE included in the Spoke 5(Cryptography and Distributed Systems Security)of the Re-search and Innovation Program PE00000014-H73C22000880001,“SE-curity and RIghts in the CyberSpace(SERICS)”,under the National Recovery and Resilience Plan,funded by the European Union,NextGen-erationEU.
文摘The interest in Self-Sovereign Identity(SSI)in research,industry,and governments is rapidly increasing.SSI is a paradigm where users hold their identity and credentials issued by authorized entities.SSI is revolutionizing the concept of digital identity and enabling the definition of a trust framework wherein a service provider(verifier)validates the claims presented by a user(holder)for accessing services.However,current SSI solutions primarily focus on the presentation and verification of claims,overlooking a dual aspect:ensuring that the verifier is authorized to access the holder’s claims.Addressing this gap,this paper introduces an innovative SSI-based solution that integrates decentralized wallets with Ciphertext-Policy Attribute-Based Proxy Re-Encryption(CP-ABPRE).This combination effectively addresses the challenge of verifier authorization.Our solution,implemented on the Ethereum platform,enhances accountability by notarizing key operations through a smart contract.This paper also offers a prototype demonstrating the practicality of the proposed approach.Furthermore,it provides an extensive evaluation of the solution’s performance,emphasizing its feasibility and efficiency in real-world applications.
文摘This work is concerned with the modelling of the interaction of fluid flow with flexibly supported rigid bodies.The fluid flow is modelled by Lattice-Boltzmann Method,coupled to a set of ordinary differential equations describing the dynamics of the solid body in terms its elastic and damping properties.The time discretization of the body dynamics is performed via the Time Discontinuous Galerkin Method.Several numerical examples are presented and highlight the robustness and efficiency of the proposed methodology,by means of comparisons with previously published results.The examples show that the present fluid-structure method is able to capture vortexinduced oscillations of flexibly-supported rigid body.
文摘The onset of cavitating conditions inside the nozzle of liquid injectors is known to play a major role on spray characteristics,especially on jet penetration and break-up.In this work,we present a Direct Numerical Simulation(DNS)based on the Lattice Boltzmann Method(LBM)to study the fluid dynamic field inside the nozzle of a cavitating injector.The formation of the cavitating region is determined via a multi-phase approach based on the Shan-Chen equation of state.The results obtained by the LBM simulation show satisfactory agreement with both numerical and experimental data.In addition,numerical evidence of bubble break-up,following upon flow-induced cavitation,is also reported.
文摘This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China＇s provinces. Using data provided by the National Bureau of Statistics of China we propose two fiscal residuum indexes for China＇s provinces over the period 1998-2004. According to Buchanan＇s original definition of fiscal residuum a first index is given by the difference between government expenditure and revenue. A second index measures enterprises＇ net fiscal benefit and is calculated as the difference between public expenditure that affect business activities and taxes paid by enterprises. We found that the first index does not significantly affect the FDI localization choice while the second one positively affects it. When looking at different subsets of provinces we found that for eastern provinces the first index has a positive and significant effect. These results confirm the role of the net fiscal benefit as a determinant of FDI inflows at the provincial level.
基金supported by the Swiss Federal Office of Energy(SFOE)and by the Italian Ministry of Education,University and Research(MIUR),through the ERA-NET Smart Energy Systems RegSys joint call 2018 project“DiGRiFlex-Real time Distribution GRid control and Flexibility provision under uncertainties.”。
文摘Photovoltaic(PV)systems are widely spread across MV and LV distribution systems and the penetration of PV generation is solidly growing.Because of the uncertain nature of the solar energy resource,PV power forecasting models are crucial in any energy management system for smart distribution networks.Although point forecasts can suit many scopes,probabilistic forecasts add further flexibility to an energy management system and are recommended to enable a wider range of decision making and optimization strategies.This paper proposes methodology towards probabilistic PV power forecasting based on a Bayesian bootstrap quantile regression model,in which a Bayesian bootstrap is applied to estimate the parameters of a quantile regression model.A novel procedure is presented to optimize the extraction of the predictive quantiles from the bootstrapped estimation of the related coefficients,raising the predictive ability of the final forecasts.Numerical experiments based on actual data quantify an enhancement of the performance of up to 2.2%when compared to relevant benchmarks.
