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Incineration has become increasingly important in many large cities around the world because of fast urbanization and population growth. The benefits of energy production and large reduction in the waste volume to landfills also contribute to its growing adaptation for solid waste management for these cities. At the same time, the environmental impact of the pollutant gases emitted from the incineration process is a common concern for various stakeholders which must be properly addressed. To minimize the pollutant gas emission levels, as well as maximize the energy efficiency, it is critically important to optimize the combustion performance of an incinerator freeboard which would require the development of reliable approaches based on computational fluid dynamics (CFD) modeling. A critical task in the CFD modeling of an incinerator furnace requires the specification of waste characteristics along the moving grate as boundary conditions, which is not available in standard CFD packages at present. This study aims to address this gap by developing a numerical incinerator waste bed model.

A one-dimensional Lagrangian model for the incineration waste bed has been developed, which can be coupled to the furnace CFD model. The changes in bed mass due to drying, pyrolysis, devolatilization and char oxidation are all included in the model. The mass and concentration of gases produced in these processes through reactions are also predicted. The one-dimensional unsteady energy equations of solid and gas phases, which account for the furnace radiation, conduction, convection and heat of reactions, are solved by the control volume method.

The Lagrangian model is validated by comparing its prediction with the experimental data in the literature. The predicted waste bed height reduction, temperature profile and gas concentration are in reasonable agreement with the observations.

The simplicity and efficiency of the model makes it ideally suitable to be used for coupling with the computational furnace model to be developed in future (so as to optimize incinerator designs).

This paper aims to investigate user preferences for the information systems in order to achieve user satisfaction by using conjoint analysis.

Conjoint analysis is applied for the measurement of user preferences on information systems by seven properties and three levels for each property. To apply the approach, two surveys were designed: the first survey investigates the main properties affecting the end-users' satisfaction for using the current information systems based upon literature review and expert interview in Phase I. The second survey weighed the preferences by the virtual profiles of the information systems, which represent the ideal systems.

The results show that speed-related properties are critical to achieve the end-user satisfaction. The next important property group is related to the access control and system integration between various business modules. From the measurements, the best system file should be constructed with the highly weighed levels of the key attributes.

The virtual profiles are complex for respondents to understand the attributes and the compounds of the virtual products. Moreover, the respondents were overwhelmed by the number of virtual profiles. The attributes were required to enable communication between researchers and respondents.

Information system designers can achieve user satisfaction by combining the highest utility levels of all attributes. Nonetheless, the trade-offs between attributes and their levels should be considered in order to apply the results to the business, depending on the system environments and business practices, by updating the importance of the determinants regularly.

This study applied the conjoint analysis to information management systems in order to design and maintain user satisfaction for the targeted company. This paper will provide alternative ways for the system engineers and developers of the case company by considering the critical attributes, which will affect both user performance and satisfaction.

Following the Supreme Court’s 1988 decision in Basic, securities class plaintiffs can invoke the “rebuttable presumption of reliance on public, material misrepresentations regarding securities traded in an efficient market” [the “fraud-on-the-market” doctrine] to prove classwide reliance. Although this requires plaintiffs to prove that the security traded in an informationally efficient market throughout the class period, Basic did not identify what constituted adequate proof of efficiency for reliance purposes.

Market efficiency cannot be presumed without proof because even large publicly traded stocks do not always trade in efficient markets, as documented in the economic literature that has grown significantly since Basic. For instance, during the recent global financial crisis, lack of liquidity limited arbitrage (the mechanism that renders markets efficient) and led to significant price distortions in many asset markets. Yet, lower courts following Basic have frequently granted class certification based on a mechanical review of some factors that are considered intuitive “proxies” of market efficiency (albeit incorrectly, according to recent studies and our own analysis). Such factors have little probative value and their review does not constitute the rigorous analysis demanded by the Supreme Court.

Instead, to invoke fraud-on-the-market, plaintiffs must first establish that the security traded in a weak-form efficient market (absent which a security cannot, as a logical matter, trade in a “semi-strong form” efficient market, the standard required for reliance purposes) using well-accepted tests. Only then do event study results, which are commonly used to demonstrate “cause and effect” (i.e., prove that the security’s price reacted quickly to news – a hallmark of a semi-strong form efficient market), have any merit. Even then, to claim classwide reliance, plaintiffs must prove such cause-and-effect relationship throughout the class period, not simply on selected disclosure dates identified in the complaint as plaintiffs often do.

These issues have policy implications because, once a class is certified, defendants frequently settle to avoid the magnified costs and risks associated with a trial, and the merits of the case (including the proper application of legal presumptions) are rarely examined at a trial.

This study aims to identify supply chain (SC) management practices applied to purchasing capable of improving the resilience of the health-care SC and mitigating the effects of material and service disruption during pandemics.

The approach adopted is qualitative and is based on a systematic literature review from the ScienceDirect, Emerald, Wiley and Web of Science databases. After selecting 705 documents, filters are applied, and 52 articles present problems faced by purchasing the health-care SC during the coronavirus disease 2019 (COVID-19) pandemic.

This article suggests five propositions of resilient practices that can increase purchasing resilience in the face of pandemics such as COVID-19. The proposed practices are collaboration, flexibility, visibility, agility and information sharing, which suggest a sequence for the adoption of management practices based on the number of occurrences and importance found in the analysed studies.

This study does not find robust empirical evidence that could categorically state that the results can be replicated in organisations in general. Thus, as a continuation of research, more studies should use an empirical methodology and case analysis to organise different branches. As the human factor was decisive for the results observed in the literature, future research should dedicate part of the studies to the psychological area of professionals. Actions to combat the pandemic were implemented, impacting positively and negatively on the results obtained. Future research on combat actions could indicate which ones should be avoided.

As a result, disruptions are expected to be reduced, and consequently, the resilience of the SC will increase. Accordingly, purchasing processes and procedures can be redefined to positively influence the resilience of the health-care SC. Resilience is related to maintaining the flow of supply, as well as systems and actions aimed at mitigating the effects of disruptions in the hospital’s core business.

Health systems need to respond to society’s needs even in the face of global crises, such as the one faced during the COVID-19 pandemic. The overload in hospitals and the exponential demand for specific medicines and services in the fight against the crisis caused by the COVID-19 pandemic require enormous coordination in procurement by the purchasing sector. This planning aims to ensure that the care provided by health services maintains the flow of value that serves hospitalised patients.

This study introduces a new approach to the recurrent problem of disruption of the health-care SC during a pandemic using a combination of five important management practices. This proves useful for mitigating disruptions and their effects on the health-care SC.

When hydrogen evolution reaction occurs on a metal surface, on the one hand, the generated hydrogen atom may penetrate into the metal that causes the hydrogen embrittlement failure of materials; on the other hand, the hydrogen generation may increase the local pressure in the coating and cause coating blistering. The purpose of this study is to study the effect of NaCl concentration and pH on hydrogen evolution reaction of X60 steel.

A cathodic polarization curve 257E-2V vs OCP and EIS was obtained by conventional three-electrode system in different NaCl concentrations, 257E3.5 and pH. Second, various parameters such as hydrogen evolution, over-potential current–density polarization resistance and capacitance of double electric layer were obtained based on fitting of the experimental data. Finally, the reaction mechanism was determined by Tafel curves.

It was concluded that in different NaCl concentrations, diffusion layer induced by concentration polarization affects the diffusion process of H+ ions, which makes over-potential increase. Under great effect of concentration polarization, the reaction is different in acid and alkaline environments, and the dielectric layer shows the characteristic of meta-alkaline adsorption, which makes difference in mechanism.

This research not only has theoretical significance but also gains utilization prospect. Ultimately, this research could be applied to clear hydrogen evolution process and protect long-distance pipeline against delamination.

The purpose of this paper is to demystify Lean for service innovation by investigating its benefits and risks. Lean innovation is a relatively new approach which is advocated in management literature. Little scientific work about its practice exists in the field. Although the Lean innovation principles are clear, there is limited evidence about their impact on service innovation processes.

From the knowledge-based view (KBV) of the firm, a framework for understanding Lean innovation is developed. Using this framework, the benefits and risks of Lean innovation are analyzed in a case study.

The case study not only shows that Lean service innovation can have many advantages, but also draws attention to the risks. The risks might result in the inability to follow Lean principles and might hamper the realization of the benefits. Using the case studies, study mitigation mechanisms are identified.

This research offers a new knowledge perspective and a better understanding of Lean service innovation. There are two main contribution of this paper. First of all, it reports on the impact of Lean innovation on a bank’s innovation processes, both its benefit and risks. This has a contribution to understanding the innovation process in service organizations. Second, this paper extends Lean innovation to a service context and contributes to the knowledge basis of Lean innovation.

This study aims to reveal how the COVID-19 vaccine was accepted in the Japanese Twitter-sphere. This study explores how the topics related to the vaccine promotion project changed on Twitter and how the topics that were likely to spread changed during the vaccine promotion project.

The computational social science methodology was adopted. This study collected all tweets containing the word “vaccine” using the Twitter API from March to October 2021 and conducted the following analysis: analyzing frequent words and identifying topics likely to spread through the cosine similarity and Tobit model.

First, vaccine hesitancy–related words were frequently mentioned during the vaccine introduction and dissemination periods and had diffusing power only during the former period. Second, vaccine administration–related words were frequently mentioned and diffused through April to May and had diffusing power throughout the period. The background to these findings is that the sentiment of longing for vaccines outweighed that of hesitancy toward vaccines during this period.

This study finds that the timing of the rise in vaccine hesitation sentiment and the timing of the start of vaccine supply were misaligned. This is one of the reasons that Japan, which originally exhibited strong vaccine hesitancy, did not face vaccine hesitancy in the COVID-19 vaccine promotion project.

This paper mentions the quick reactions of Vietnam to avoid explosive catastrophes before and during the first wave of the coronavirus pandemic. The work presented here has profound implications for future research of disaster response and preparation for future pandemics. In order to estimate the causal general effect of the pandemic, the authors have to do a quantitative survey at the end of the pandemic.

The difference in damage caused by the pandemic between the great powers and Vietnam is the quick reaction. It plays a decisive role. In attempting to tackle emerging phenomena in the pandemic, this study is deliberately broad-based. Considerable attention is given to explaining each methodological choice. It centers on a core case of Vietnam. Using data from multiple methods, it adopts publish media and contemporary research during the pandemic as a way to draw out key themes within the core case.

The paper focuses on the lessons for the post-pandemic consist of the Buddhist conception (cause and effect) based on the quick reaction of the Vietnamese government and the adaptation of Vietnamese people. This is a key success for the future anti-pandemic process.

The paper is not exploring the pandemic within a larger scale of all nations to approach a general lesson for the world.

The success of the first anti-pandemic phase does not guarantee that subsequent efforts will be successful. Respecting the “opponent” (the coronavirus) is the best way to avoid falling into the deadly subjective trap that some great powers have encountered.

This article highlights the rapid response of the Vietnamese before and during the coronavirus pandemic. From that, the article draws some lessons for the next similar disasters based on the cause and effect.

A quick reaction is one of the most important ways to deal with any disaster. After a half year of the coronavirus pandemic spread, Vietnam has 408 infectious cases and no deaths within 96,208,984 people (The Ministry of Health of Vietnam on July 22nd, 2020). Vietnam achieved success with the least expensive price that should be finding in risks and issues in the future.