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The purpose of this paper is to gain a better understanding on how metasurfaces behave, in terms of currents in each unit cell. A better knowledge of their behavior could lead to an ad-hoc design for specific applications.

The methodology used is both theoretical and numerical; it is based on circuit theory and on an optimization procedure.

The results show that when the knowledge of the current in each unit cell of a metasurface is needed, the most common approximations currently used are often not accurate. Furthermore, a procedure for the termination of a metasurface, with application-driven goals, is given.

This paper investigates the distribution of the currents in a 2D metamaterial realized with magnetically coupled resonant coils. Different models for the analysis of these structures are illustrated, and the effects of the approximations they introduce on the current values are shown and discussed. Furthermore, proper terminations of the resonators on the boundaries have been investigated by implementing a numerical optimization procedure with the purpose of achieving a uniform distribution of the resonator currents. The results show that the behavior of a metasurface (in terms of currents in each single resonator) depends on different properties; as a consequence, their design is not a trivial task and is dependent on the specific applications they are designed for. A design strategy, with lumped impedance termination, is here proposed.

This study aims to analyse the non-linear losses of a porous media (stack) composed by parallel plates and inserted in a resonator tube in oscillatory flows by proposing numerical correlations between pressure gradient and velocity.

The numerical correlations origin from computational fluid dynamics simulations, conducted at the microscopic scale, in which three fluid channels representing the porous media are taken into account. More specifically, for a specific frequency and stack porosity, the oscillating pressure input is varied, and the velocity and the pressure-drop are post-processed in the frequency domain (Fast Fourier Transform analysis).

It emerges that the viscous component of pressure drop follows a quadratic trend with respect to velocity inside the stack, while the inertial component is linear also at high-velocity regimes. Furthermore, the non-linear coefficient b of the correlation ax + bx² (related to the Forchheimer coefficient) is discovered to be dependent on frequency. The largest value of the b is found at low frequencies as the fluid particle displacement is comparable to the stack length. Furthermore, the lower the porosity the higher the Forchheimer term because the velocity gradients at the stack geometrical discontinuities are more pronounced.

The main novelty of this work is that, for the first time, non-linear losses of a parallel plate stack are investigated from a macroscopic point of view and summarised into a non-linear correlation, similar to the steady-state and well-known Darcy–Forchheimer law. The main difference is that it considers the frequency dependence of both Darcy and Forchheimer terms. The results can be used to enhance the analysis and design of thermoacoustic devices, which use the kind of stacks studied in the present work.

The electrical properties of piezoelectric vibrators have a crucial influence on the operating state of ultrasonic motors. In order to solve the problem that the current piezoelectric vibrator generates a large amount of heat during vibration to degrade its performance, which in turn affects the normal operation of ultrasonic motors, this paper prepares a novel piezoelectric vibrator and tests its maximum vibration velocity under the working condition, which is more than twice as much as that of the current commercial PZT-8.

The crystal structures of the samples were analyzed by using an X-ray diffractometer. For microstructure observation, samples were observed by scanning electron microscope (SEM). The quasi-static piezoelectric coefficient meter (ZJ-3AN) was used for piezoelectric measurement. Dielectric properties were measured by utilizing an impedance analyzer (Agilent 4294A) with a laboratory heating unit. Ferroelectric hysteresis loops were obtained using a ferroelectric analyzer (Radiant, Multiferroic 100). A Doppler laser vibrometer (Polytec PSV-300F, Germany) and a power amplifier were used for piezoelectric vibration measurements, during which the temperature rise was determined by an infrared radiation thermometer (Victor 303, China).

The ceramics exhibit enhanced piezoelectric performance at 0.1–0.4 mol% of Yb doping contents. The ceramic of 0.4 mol% Yb reaches the maximal internal bias field and presents a larger mechanical quality factor of 1,692 compared with that of 0.2 mol% Yb-doped ceramic, in spite of a slightly decreased dielectric constant of 439 pC/N, the unit of the piezoelectric constant, which is the ratio of the local charge (pC) to the frontal force (N) and electromechanical coupling coefficient of 0.63. The vibrator with this large mechanical quality factor ceramic displays a vibration velocity of up to 0.81 m/s under the constraint of 20 °C temperature rising, which is much higher than commercial high-power piezoelectric ceramics PZT-8.

The enhanced high-power properties of the piezoelectric vibrator by Yb doping may provide a potential application for the high-performance USM and offer the possibility of long-term stable operation under high power for special equipment like USM. In the subsequent phase of research, the novel PZT-based high-power piezoelectric vibrator can be utilized in the USM, and the motor's performance will be evaluated under aerospace conditions to objectively assess the reliability of the piezoelectric vibrator.

The purpose of the article is to outline the insights provided by Alan Fox in Man Mismanagement in relation to the rise of the New Right political economy and the spread of unitarist managerialism. The article assesses the contemporary work and employment relations implications of mismanagement arising from a “second wave” of the New Right ideology from 2010 in the UK.

Responding to the Special Issue on Alan Fox, the article focuses on Alan Fox's book Man Mismanagement, considering industrial relations developments arising between the 1st (1974b) and 2nd (1985) editions relating to the political rise of the New Right. It reviews various literature that illustrates the contemporary IR relevance of the book and Fox's insights.

The New Right’s ideology has further fragmented work, disjointed labour rights and undermined collective industrial relations institutions, and macho mismanagement praxis is even more commonplace, compared to when Fox wrote Man Mismanagement. The stripping away of the institutional architecture of IR renders the renewal of pluralist praxis, like collective bargaining and other forms of joint regulation of work, a formidable task.

The value of the article relates to the identification of dramatic historical industrial relations events and change in the UK in Alan Fox's book Man Mismanagement, most notably relating to the rise to power of the Thatcherite New Right in 1979. Originality is evidenced by the authors’ drawing on Fox's ideas and assessing the implications of the “second wave” of the New Right in the contemporary industrial relations (IR) context of the 2020s under the conceptual themes of fragmented work, disjointed labour rights and undermined collectivism.

The purpose of this paper is to analyze numerically the blowup in finite time of the solutions to a one-dimensional, bidirectional, nonlinear wave model equation for the propagation of small-amplitude waves in shallow water, as a function of the relaxation time, linear and nonlinear drift, power of the nonlinear advection flux, viscosity coefficient, viscous attenuation, and amplitude, smoothness and width of three types of initial conditions.

An implicit, first-order accurate in time, finite difference method valid for semipositive relaxation times has been used to solve the equation in a truncated domain for three different initial conditions, a first-order time derivative initially equal to zero and several constant wave speeds.

The numerical experiments show a very rapid transient from the initial conditions to the formation of a leading propagating wave, whose duration depends strongly on the shape, amplitude and width of the initial data as well as on the coefficients of the bidirectional equation. The blowup times for the triangular conditions have been found to be larger than those for the Gaussian ones, and the latter are larger than those for rectangular conditions, thus indicating that the blowup time decreases as the smoothness of the initial conditions decreases. The blowup time has also been found to decrease as the relaxation time, degree of nonlinearity, linear drift coefficient and amplitude of the initial conditions are increased, and as the width of the initial condition is decreased, but it increases as the viscosity coefficient is increased. No blowup has been observed for relaxation times smaller than one-hundredth, viscosity coefficients larger than ten-thousandths, quadratic and cubic nonlinearities, and initial Gaussian, triangular and rectangular conditions of unity amplitude.

The blowup of a one-dimensional, bidirectional equation that is a model for the propagation of waves in shallow water, longitudinal displacement in homogeneous viscoelastic bars, nerve conduction, nonlinear acoustics and heat transfer in very small devices and/or at very high transfer rates has been determined numerically as a function of the linear and nonlinear drift coefficients, power of the nonlinear drift, viscosity coefficient, viscous attenuation, and amplitude, smoothness and width of the initial conditions for nonzero relaxation times.

This study aims to determine how the most sustainable brands in Italy and Spain developed communication and awareness-raising actions during the COVID-19 pandemic and whether these companies were truly involved in raising public awareness of the pandemic. The authors specifically focus on sustainable companies, as health communication is considered to be an important corporate social responsibility task.

To answer these questions, the authors have used data on the social media activity (Twitter and Instagram) of these brands in Spain and Italy, extracting the posts and associated hashtags that each of them has published throughout the pandemic to be processed using social network analysis and visualization techniques.

The detailed analysis of both the levels of activity and the content of the messages provides interesting insights into the communication models of the companies and the influence of factors such as time, country and the specific social media platform used.

The authors analyze the communication of the most sustainable businesses on social media during the pandemic, adopting a highly innovative approach. The particular originality of this study lies in the parallel analysis of two different countries that were simultaneously shaken by the pandemic in very similar circumstances. This study also presents a novel use of graphical representation tools in terms of companies’ behavior for health communication on social media.

El objetivo de esta investigación es determinar cómo las marcas reconocidas como las más sostenibles en Italia y España han desarrollado acciones de comunicación durante la pandemia del Covid-19 y si estas empresas se han involucrado realmente en la sensibilización pública de la pandemia. Nos centramos específicamente en las empresas sostenibles dado que la Comunicación en Salud se considera una tarea importante de responsabilidad social corporativa.

Para responder a estas preguntas, hemos utilizado datos de actividad en medios sociales (Twitter e Instagram) de estas marcas en España e Italia, extrayendo los posts y hashtags asociados que cada una ha publicado a lo largo de la pandemia para procesarlos usando técnicas de análisis y visualización de redes sociales.

El análisis detallado tanto de los niveles de actividad como del contenido de los mensajes permite obtener conclusiones interesantes sobre los modelos de comunicación de las empresas y la influencia de factores como el tiempo, el país y el medio social concreto utilizado.

Analizamos la comunicación realizada por las compañías más sostenibles en medios sociales durante la pandemia, adoptando un enfoque muy innovador. La particularidad de este estudio radica en el análisis paralelo de dos países diferentes que fueron sacudidos simultáneamente por la pandemia en circunstancias muy similares. Este estudio también conlleva un uso novedoso de herramientas de representación gráfica en términos del comportamiento de las empresas para Comunicación en Salud en medios sociales.

本研究的目的是确定在意大利和西班牙被认为是最可持续发展的品牌在Covid-19大流行期间是如何开展传播行动的, 以及这些公司是否真正参与了提高公众对该大流行病的认识。我们特别关注可持续发展的公司, 因为健康传播被认为是企业社会责任的一项重要任务。

为了回答这些问题, 我们使用了这些品牌在西班牙和意大利的社交媒体活动数据（Twitter和Instagram）, 提取了每个品牌在整个大流行期间发布的帖子和相关标签, 并使用社交网络分析和可视化技术进行处理。

通过对活动水平和信息内容的详细分析, 可以得出关于这些公司的传播模式以及诸如时间、国家和所使用的特定社交媒体等因素的影响的有趣结论。

我们分析了最可持续的公司在大流行期间在社交媒体上进行的传播, 采取了一种非常创新的方法。这项研究的特殊性在于对两个不同国家的平行分析, 这两个国家在非常相似的情况下同时受到大流行病的冲击。这项研究还包括在社交媒体上对公司健康传播行为的图形表示工具的新颖使用。

This paper aims to examine the regional dynamics that further consolidated Israel’s national security in the Middle East in the aftermath of the Arab Spring, reflecting upon the nuclear challenge between Iran and Israel and Iran's expanding activities in the region.

To prove the central argument, the study uses a conceptual framework that centers on deterrence as the main approach used by states to consolidate their influence in the Middle East region.

Iran's nuclear progress and influence in the region has strengthened Israel’s security and fostered an unprecedented open rapprochement led by USA efforts with the Gulf regimes.

The paper draws particular attention to the Iran–Israel nuclear competency, and the Israeli preferred policy options regarding Iranian activities in the region amid turbulent Middle East. In addition, the paper offers insight to the regional dynamics that further consolidated Israel’s national security in the region while maintaining a status of Arab vulnerability and backwardness.

The purpose of this study is to investigate the concept of vicarious moral cleansing and scrutinize whether unethical behavior of leaders initiate moral cleansing in subordinates or not. This study also highlights a boundary condition under which employees are motivated to cleanse their moral self-image through increased organizational citizenship behaviors and decreased counterproductive work behaviors.

The study is quantitative based on hypothesis testing. By adopting convenience sampling technique, employees working at all managerial levels of service sector organizations were asked to fill out the questionnaires. Being a time-lagged study, data for independent variable (unethical leadership) and moderator (relational self-construal) were collected at T1, data for mediator (moral self-image) were collected at T2 and data for outcomes (OCBs, CWBs) were collected at T3 from same respondents. To rule out the possibility of common method bias and social desirability bias, a multi-wave design was adopted and respondents were asked to provide unique keys/IDs instead of their names.

This study investigated the impact that unethical leaders impose on employee self-concept. Moreover, this study also explored the motivational tendencies of moral self-image. Findings suggest that employees' desirable or undesirable behaviors against leader are dependent upon the perceptions related with their own role, self-image and perception of leader's integrity and intentions. Leader's unethicality is perceived threatening for their own moral self-image and they deal with it constructively. This study has laid the foundation for presence of vicarious moral cleansing in organizational setup, and it is advised that researchers must investigate this phenomenon in different settings to provide useful insights.

Due to lack of resources, employing a pure longitudinal research design was not feasible, and therefore a time-lagged research design was used to gather data from only two cities of Pakistan. However, authors believe that a longitudinal research design, with data collection from a larger sample, will provide more fine-grained results. Secondly, use of perceived leader's integrity scale to measure unethical leadership is another limitation. Although the authors tried to address this issue by conducting an EFA and adopting only suitable items, yet a new scale which is able to measure the true essence of unethical leadership ought to be developed.

Use of moral self-image as an indicator of moral cleansing is an additional contribution of this study, as previous studies used levels of guilt as driving force behind moral cleansing and compensatory cleansing. Most of the studies on unethical leadership as well as moral cleansing took place in the Western context and scholars' stress that culture can substantially influence outcomes of these constructs. Thus, this study extends the literature on moral cleansing and moral self-regulation by developing and testing a model in cultural settings of Pakistan.

本研究擬探討間接感受到的道德清洗 (以下簡稱間接道德清洗) 這個概念；研究亦會仔細審視領袖的不道德行為會否在其下屬間引起道德清洗。就此而言，本研究亦強調了一個邊界條件，在這邊界條件之下，僱員透過組織公民行為的增加，以及為工作目標帶來負面影響的工作行為的減少得到激勵，進而淨化他們的道德自我形象。

本研究為一個基於假設檢定的量性研究；研究採用任意抽樣方法而進行。在服務業機構內不同管理階層工作的僱員被邀回答問卷；由於這是一個時滯研究，即使是同一的答覆者，IV (不道德的領導) 和仲裁人(關係型自我建構)的數據在T1收集，調解員 (道德自我形象) 的數據在T2收集，結果 (OCBs，CWBs) 的數據在T3收集，為了排除共同方法偏差和社會期許誤差的出現，研究採用多波浪設計，而且，答覆者必須提供獨一無二的密鑰或身份證明，而不是提供他們的名字。

本研究探討了不道德的領袖對僱員自我概念的影響；研究亦探索了可能推動道德自我形象的因素。研究結果暗示、僱員會做對領袖而言可取的行為與否，全視乎他們如何看待自己的角色和自我形象，也視乎他們對領袖的誠信和動機有甚麼看法。領袖若不道德，這會被認為會對僱員的道德自我形象做成威脅，在這情況下，僱員會積極地應付這個威脅。本研究為在組織架構內存有間接道德清洗這個觀點打下基礎。今後的研究學者或許應就不同的環境、對這個現象進行探討和研究，以使我們能更深刻地瞭解這個課題。

從前的研究均採用內疚的程度、作為道德清洗和補償清洗背後的推動力 (Liao et al., 2018) 。本研究另外的貢獻在於採用了道德自我形象、作為道德清洗的指標。以前關於不道德領導以及道德清洗的研究，大多以西方國家為背景。研究學者均強調文化因素會很大程度地影響這些觀念帶來的結果；因此，本研究透過設計一個以巴基斯坦文化為背景的模型、並對其進行測試、來擴展有關道德清洗及道德自我調節的文獻。

The competition in the academe has always been tough, but today, the academe seems to be more like an industry than an academic community as academics are evaluated through quantified and economic means.

This article leans on Heidegger’s thoughts on the essence of technology and his ontological view on being to show the dangers that lie in this quantification of researchers and research.

Despite the benefits that information systems (ISs) offer to people and research, it seems that technology has made it possible to objectify researchers and research. This has a negative impact on the academe and should thus be looked into especially by the IS field, which should note the problems that exist in its core. This phenomenon of quantified academics is clearly visible at academic quantification sites, where academics are evaluated using metrics that count their output. It seems that the essence of technology has disturbed the way research is valued by emphasising its quantifiable aspects. The study claims that it is important to look for other ways to evaluate researchers rather than trying to maximise research production, which has led to the flooding of articles that few have the time or interest to read.

This paper offers new insights into the current phenomenon of quantification of academics and underlines the need for critical changes if in order to achieve the academic culture that is desirable for future academics.