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This paper aims to present a novel adaptive sliding mode control (ASMC) method based on the predefined performance barrier function for reusable launch vehicle under attitude constraints and mismatched disturbances.

A novel ASMC based on barrier function is adopted to deal with matched and mismatched disturbances. The upper bounds of the disturbances are not required to be known in advance. Meanwhile, a predefined performance function (PPF) with prescribed convergence time is used to adjust the boundary of the barrier function. The transient performance, including the overshoot, convergence rate and settling time, as well as the steady-state performance of the attitude tracking error are retained in the predetermined region under the barrier function and PPF. The stability of the proposed control method is analyzed via Lyapunov method.

In contrast to conventional adaptive back-stepping methods, the proposed method is comparatively simple and effective which does not need to disassemble the control system into multiple first-order systems. The proposed barrier function based on PPF can adjust not only the switching gain in an adaptive way but also the convergence time and steady-state error. And the efficiency of the proposed method is illustrated by conducting numerical simulations.

A novel barrier function based ASMC method is proposed to fit in the amplitude of the mismatched and matched disturbances. The transient and steady-state performance of attitude tracking error can be selected as prior control parameters.

The purpose of this paper is to analyze the impact of the coronavirus (COVID-19) pandemic on participation and time allocated to work from home (WFH) by ethnic/racial group.

The authors employ USA time-use data [American Time Use Survey (ATUS)] for the 2017–2020 period and a parametric approach in their analysis.

Estimates show that the time allocated to WFH increased during COVID-19, especially for women. This increase is likely driven by more workers shifting to WFH (higher participation) rather than by longer hours worked by those who already teleworked. The authors also find relevant differences in the impact of COVID-19 on WFH by ethnic/racial group. Among ethnic/racial groups, only Asians increased WFH compared to White Americans. Within this ethnic group, the authors find significant differences across genders. Asian men increased participation in WFH, whereas Asian women increased both participation and hours worked, compared to White American women. Differences in this racial/ethnic group could be explained by previous research, which demonstrates a higher ability of Asians to perform job tasks remotely. However, this finding could also be attributed to an increase in discrimination during the COVID-19 pandemic.

This paper contributes to the recent and limited literature exploring the heterogeneous impact of COVID-19 on participation and time allocated to WFH by ethnic/racial group. Understanding the mechanisms driving vulnerable populations' abilities to work during socioeconomic downturns is of high policy importance.

This paper explores the development of microcredentials (MCs) through a regional lens, considering their implications for lifelong learning and skilled labour mobility in Asia and the Pacific. It also examines recent global initiatives led by the United Nations Educational, Scientific and Cultural Organization (UNESCO).

The study reviews recent global initiatives aimed at developing shared definitions and principles for MCs, as led by UNESCO, taking into account the importance of existing initiatives such as the pilot project launched by the Australian government in 2022. The formalization of MCs within national education systems is also examined, with reference to frameworks developed by organizations like the European Union (EU), Australia and the Malaysia Qualifications Agency (MQA, 2020).

The paper underscores the increasing attention from international organizations and governments to the development and recognition of MCs, with significant efforts in countries like Australia and pilot initiatives in New Zealand and Malaysia. However, it also highlights that many MC projects in Asia are still in their early developmental stages, emphasizing the need for further progress and formalization.

This paper offers a unique perspective on the development of MCs in the Asia–Pacific region and their potential role in international education. It explores the prospects for MCs in international education, including student mobility and cross-border online courses. The challenge of integrating MCs into existing systems for recognizing international qualifications is discussed. Overall, the paper contributes to the understanding of MC frameworks as essential tools in the formalization of lifelong learning in the region, supported by the provided citations (OECD, 2021).

Islanding detection has become a serious concern due to the extensive integration of renewable energy sources. The non-detection zone (NDZ) and system-specific applicability, which are the two major issues with the islanding detection methods, are addressed here. The purpose of this paper is to devise an islanding detection method with zero NDZ and, which will be applicable to all types of renewable energy sources using the sequence components of the point of common coupling voltage.

Here, a parameter using the sequence components is derived to devise an islanding detection method. The parameter derived from the sequence components of point of common coupling voltage is analysed using wavelet transform. Various operating conditions, such as islanding and non-islanding, are considered for several test systems to evaluate the performance of the proposed method. All the simulations are carried out in Simulink/MATLAB environment.

The results showed that the proposed method has zero NDZ for both inverter- and synchronous generator-based renewable energy sources. In addition, the proposed method works satisfactorily as per the IEEE 1547 standards requirement.

Performance of the proposed method has been tested in several test systems and is found to be better than some conventional methods.

One of the major goals of sustainable development is creating employment opportunity among all. Despite its largest demographic dividends, the whole world faces challenges in employment generation among youth. The growing number of unemployed youths is one of the important problems faced by developed as well-developing countries. Youth unemployment is the situation of young people who are looking for a job but cannot find a job in the age between 15 and 24. Mismatch between education and employability resulted in high unemployment rates among the youth. A key research question is that how we can bridge the gap and equip the youth for job field. Although eminent economists, newspapers, international statistical bodies continuously put fingers towards this vulnerability, research work in this field is really scant. On this backdrop, this chapter wants to explore the intensity of youth unemployment in India; keeping in mind, India has the largest youth population in the world. Based on data sources from World Development Indicators, the chapter studies the time series since globalisation to COVID periods. This chapter also tries to search the macroeconomic variables related anyway to the youth unemployment rate. As research methodology, we use vector autoregressive (VAR) Granger causality test. Based on our results, the author has concluded that human development index in India and GDP both ways causes each other. And youth unemployment rate in India causes HDI. However, our econometric investigations can be useful to better assessment of youth unemployment in India from liberalisation to pandemic. At the end of this chapter, some final considerations and policy implications on youth labour market dynamics are analysed and discussed.

First-generation college students in the United States are a unique demographic that is often characterized by the institutions that serve them with a risk-laden and deficit-based model. However, our analysis of the transcripts of open-ended, semi-structured interviews with 22 “first-gen” respondents suggests they are actively deft, agentic, self-determining parties to processes of identity construction that are both externally imposed and potentially stigmatizing, as well as exemplars of survivance and determination. We deploy a grounded theory approach to an open-coding process, modeled after the extended case method, while viewing our data through a novel synthesis of the dual theoretical lenses of structural and radical/structural symbolic interactionism and intersectional/standpoint feminist traditions, in order to reveal the complex, unfolding, active strategies students used to make sense of their obstacles, successes, co-created identities, and distinctive institutional encounters. We find that contrary to the dictates of prevailing paradigms, identity-building among first-gens is an incremental and bidirectional process through which students actively perceive and engage existing power structures to persist and even thrive amid incredibly trying, challenging, distressing, and even traumatic circumstances. Our findings suggest that successful institutional interventional strategies designed to serve this functionally unique student population (and particularly those tailored to the COVID-moment) would do well to listen deeply to their voices, consider the secondary consequences of “protectionary” policies as potentially more harmful than helpful, and fundamentally, to reexamine the presumption that such students present just institutional risk and vulnerability, but also present a valuable addition to university environments, due to the unique perspective and broader scale of vision their experiences afford them.

The gift-giving literature has documented several cases in which givers and recipients do not see eye-to-eye in gift-giving decisions. To help integrate this considerable segment of the gifting literature, this paper aims to develop a social norms-based framework for understanding and predicting giver-recipient asymmetries in gift selection.

Five experimental studies test the hypotheses. Participants in these studies evaluate gifts used in previous research, choose between gifts as either gift-givers or gift-recipients, and/or indicate their level of discomfort with choosing different kinds of gifts. The gifts vary in ways that allow the authors to test the social norms-based framework.

Gift-giving asymmetries tend to occur when one of the gifts under consideration is less descriptively, but not less injunctively, normative than the other. This theme holds for both asymmetries recorded in the gift-giving literature and novel ones. Indeed, the authors document new asymmetries in cases where the framework would expect asymmetries to occur and, providing critical support for the framework, the absence of asymmetries in cases where the framework would not expect asymmetries to emerge. Moreover, the authors explain these asymmetries, and lack thereof, using a mechanism that is novel to the literature on gift-giving mismatches: feelings of discomfort.

This research has multiple theoretical implications for the literatures studying gift-giving and social norms. A limitation of this work is that it left some (secondary) predictions of its model untested. Future research could test some of these predictions.

Billions of dollars are spent on gifts each year, making gift-giving a research topic of great practical importance. In addition, the research offers suggestions to consumers giving gifts, consumers receiving gifts, as well as marketers.

The research is original in that it creates a novel framework that predicts both the presence and absence of gift-giving asymmetries, introduces a psychological mechanism to the literature on giver-recipient gift choice asymmetries, and unifies many of the mismatches previously documented in this literature.

This paper aims to challenge the view of Sweden’s climate leadership by problematizing its domestic climate adaptation governance and highlighting the need for a more holistic view of adaptation. The paper highlights aspects that are troublesome for not only the built environment along coastlines but also the future of Sweden’s standing as a climate leader. The paper concludes with recommendations addressing the key areas of climate adaptation fragmentation in Sweden and calls for a more holistic view of adaptation, and one that takes into account resources, collaboration and coherence of governance vision.

The paper is a comprehensive analysis of internal governance processes in climate change adaptation. It is based on an extensive literature review and semi-structured interviews at the local level – i.e. municipalities – who have the primary responsibility for adaptation to climate change in Sweden.

Findings point to three-fold concerns. First, there is a lack of clarity on roles and responsibilities in adaptation among municipalities, regions and governmental agencies. Second, the gap between available finance and actual needs for climate change adaptation presents a major challenge when channels and pathways are not clear either. Finally, some adaptation strategies on both the local and national scales may be maladaptive in the long term.

Sweden consistently ranks highly in different climate performance indices and has acquired an international reputation as a climate leader. The paper challenges this narrative. Through a closer look the paper’s findings reveal a more fragmented picture of climate adaptation governance in the country with a myriad of unresolved questions and ad hoc solutions, where adaptation challenges are more pronounced and manifest in the built environment along the coastlines.

Many in the private and public sectors see headhunting as a “necessary evil.” A tour of investors, business schools, executive and supervisory board directors throws up unflattering descriptions. Accusations of “opacity” are probably linked to the industry’s duty of discretion. Other observers signal a need for improvement: “pumping the same names around,” “emphasis on reputation, not merit,” “lack of quality” and “low innovation.” The battle to professionalize is underway. We look at the avenues ahead for executive hiring, the demise of the “old boys’ network” and the need for diversity and sustainability in modern organizations. We present the difficulties of running a headhunting firm, and distinguishing factors of the best players. We argue that selecting a headhunter demands the same rigor as choosing a lawyer, and six areas of improvement for executive search firms. Unpacking the Spartan marathon to the boardroom, we reveal the surprising estimates of the number of new high potentials entering the market annually. We conclude by looking at possible blind spots on both sides of the hiring equation that can undermine company interests, and continue to examine the march to professionalize the executive search industry.

An earlier form of this chapter by the author was published in Dutch in “Bestemming Boardroom: over zoeken en gevonden worden” (Boom, Amsterdam, 2018) and in English (online) by the Amrop Partnership (2021) as “Destination Boardroom 3: Mapping the Executive Search World.”