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This study aims to outline the current challenges in ultrasonic additive manufacturing (AM). AM has revolutionized manufacturing and offers possible solutions when conventional techniques reach technological boundaries. Ultrasonic additive manufacturing (UAM) uses mechanical vibrations to join similar or dissimilar metals in three-dimensional assemblies. This hybrid fabrication method got attention due to minimum scrap and near-net-shape products.

This paper reviews significant UAM areas in process parameters such as pressure force, amplitude, weld speed and temperature. These process parameters used in different studies by researchers are compared and presented in tabular form. UAM process improvements and understanding of microstructures have been reported. This review paper also enlightens current challenges in the UAM process, process improvement methods such as heat treatment methods, foil-to-foil overlap and sonotrode surface roughness to increase the bond quality of welded parts.

Results showed that UAM could solve various problems and produce net shape products. It is concluded that process parameters such as pressure, weld speed, amplitude and temperature greatly influence weld quality by UAM. Post-weld heat treatment methods have been recommended to optimize the mechanical strength of ultrasonically welded joints process parameters. It has been found that the tension force is vital for the deformation of the pre-machined structures and for the elongation of the foil during UAM bonding. It is recommended to critically investigate the mechanical properties of welded parts with standard test procedures.

This study compiles relevant research and findings in UAM. The recent progress in UAM is presented in terms of material type, process parameters and process improvement, along with key findings of the particular investigation. The original contribution of this paper is to identify the research gaps in the process parameters of ultrasonic consolidation.

The authors present the impact of the coronavirus disease 2019 (COVID-19) pandemic on community lifelines. The state machinery has several departments to secure essential lifelines during disasters and epidemics. Many countries have formed national disaster management authorities to deal with manmade and natural disasters. Typical lifelines include food, water, safety and security, continuity of services, medicines and healthcare equipment, gas, oil and electricity supplies, telecommunication services, transportation means and education system. Supply chain systems are often affected by disasters, which should have alternative sources and routes. Doctors, nurses and medics are front-line soldiers against diseases during pandemics.

The COVID-19 pandemic has revealed how much we all are connected yet unprepared for natural disasters. Political leaders prioritize infrastructures, education but overlook the health sector. During the recent pandemic, developed countries faced more mortalities, fatalities and casualties than developing countries. This work surveys the impact of the COVID-19 pandemic on health, energy, environment, industry, education and food supply lines.

The COVID-19 pandemic caused 7% reductions in greenhouse gas (GHG) emissions during global lockdowns. In addition, COVID-19 has affected social fabric, behaviors, cultures and official routines. Around 2.84 bn doses have been administrated, with approximately 806 m people (10.3% of the world population) are fully vaccinated around the world to date. Most developed vaccines are being evaluated for new variants like alpha, beta, gamma, epsilons and delta first detected in the UK, South Africa, Brazil, USA and India. The COVID-19 pandemic has affected all sectors in society, yet this paper critically reviews the impact of COVID-19 on health and energy lifelines.

This paper critically reviews the health and energy lifelines during pandemic COVID-19 and explains how these essential services were interrupted.

This paper critically reviews the health and energy lifelines during pandemic COVID-19 and explains how these essential services were interrupted.

The purpose of this paper is to optimize the processing conditions of ready-to-eat (RTE) milk “coagulum” rings.

Milk “coagulum” rings were prepared from milk coagulum. Milk at four different level of milk fat (0.1, 1.5, 3 and 4.5 percent) were used to obtain milk coagulum of four different fat level for preparing milk “coagulum” rings. Unripe banana powder (UPB) and banana peel powder (BPP) were incorporated at three different levels separately. The incorporation levels were also optimized to be 11 percent for UPB and 6 percent for BPP on the basis of sensory evaluation.

The yield, ash, moisture and total dietary fiber content of products with optimized level of UPB and BPP were significantly higher as compared to control while the protein and fat contents were lower. Incorporation of extenders resulted in a significant reduction in the color value of the treated products. The water activity was highest for T₂ and lowest for control at the end of 42 days. TBARS as lipid oxidation parameter was highest for control and the microbial count was comparable in T₁ and T₂ where as it was higher in control. The sensory scores of the control was higher than the two treated products during the entire storage period.

The shelf stable RTE milk coagulum-based snack using 1.5 percent fat can provide a nutritious, palatable and healthy product to the consumers.

Pakistan's present war against extremists has many folds and sheds. The country's initial participation in the Afghan War in 1979 later gave birth to different extremist trends in the country. State patronage of the extremist Wahabi Islamists during the Afghan jihad opened another conflict in Pakistan, and things became more complicated. The combination of external and internal factors gave birth to the worst kind of conflict, which now has not only become dangerous for the country's own existence but also a major threat for global peace. The Afghan jihad initially started as a war against Soviet occupation and later became the hub of global jihad-war against infidels.

This chapter analyzes how external factors promoted internal contradictions in Pakistan due to which the country became not only an exporter of jihadis for the world but also the worst kind of sectarian conflicts, including. Shia–Sunni, Deobandi–Wahabi clashes, entered into in the past two decades. Such a strong link exists with Pakistan's official support to global jihad. Draft sectarian groups now head to head with their opponents have killed thousands of members of rival sectors, have strong support from external sympathizers, and have spread in the country. The well planned terrorist activities of these groups reflect the fact that support to these groups in the past is now leading to a severe crisis in Pakistan. The nexuses of these indigenous extremists like Lashkar-e-Jhangvi, Lashkar-e-Taiba, Tehrik-e-Taliban Pakistan, and Hizb-ul-Mujahideen with external terrorist organizations like Al-Qaeda, the Taliban, and Islamic Movement of Uzbekistan of Tahir Yuldasher Chechen Guerilla War has led to several bloody clashes in the country and outside.

Despite the spread in usage and ownership of credit cards, few studies have examined its effect on consumer debt in developing nations. The main purpose of this paper is to understand consumers' attitude and spending behavior using credit cards.

This study is based on a questionnaire survey conducted in Malaysia. Based on an extensive review of literature, a model is developed to identify the psychographic factors that influence the consumer attitudes toward using credit cards.

The paper found support for some of the theoretical expectations and lends support to some of the earlier deviations reported in the literature.

The findings are likely to be important to banks and financial institutions issuing credit cards, as they help managers to have a better understanding of cardholders in Malaysia and their attitude and behavior toward usage of credit cards.

This paper makes a valuable contribution given the fact that there is a dearth of empirical studies of this nature focusing on Malaysia.

This paper aims to identify the unidimensionality and reliability of 84 factors that influence the performance of construction projects and develop a confirmatory factor analysis (CFA) model.

The study adopted a deductive research approach and started by identifying the positive factors that influence construction project performance. This was followed by the modification of the identified factors. After that, a questionnaire was developed out of the factors for data collection. Exploratory factor analysis was used to establish the factor structure of the positive factors, and this was verified using CFA afterwards. A model fit analysis was performed to determine the goodness of fit of the hypothesised model, followed by the development of the confirmatory model.

The study demonstrated substantial correlation in the data, sufficient unidimensionality and internal reliability. In addition, the estimated fit indices suggested that the postulated model adequately described the sample data.

The paper revealed that performance can be enhanced if stakeholders identify and leverage the positive factors influencing performance. The paper suggests that project stakeholders, particularly government, project owners, consultants and construction firms, can improve project performance by critically examining economic and financial systems (EFS), regulation and policy-making systems (RPS), effective management practices (EMP) and project implementation strategies (PIS).

The contribution of this paper to the present literature is identifying the positive factors and developing the confirmatory factor model. The model comprised 42 positive variables under four indicators: EMP, RPS, PIS and EFS.

Work–family conflict (WFC) is rife among construction professionals, leading to a significant negative impact on their work engagement. Building on an extant body of research, this study provides nuanced insights into the link between WFC, work–life balance (WLB) and work engagement and identifies the boundary conditions of these relationships.

Data were collected from 257 dyads of construction professionals and their immediate supervisors from a sample of five construction firms based in India using an online survey.

The results found that WLB mediates the relationship between WFC and work engagement, and the relationship is controlled by professionals' gender and perceptions of psychological contract breach (PCB). An important finding is that PCB accentuates the negative influence of WFC on work engagement via WLB. The study also reveals that the negative impact of WFC on WLB is stronger for women.

The findings are relevant for construction firms since they are primarily dominated by men and continue to struggle to attract more women professionals. The study insights provide avenues to expand existing research on the relationship between WFC and work engagement and offer managerial implications for improving construction professionals' work engagement in the high-pressure context of the construction industry.

The study significantly advances the underdeveloped literature on work–family interface, especially in the unique work settings of the construction industry, by establishing WFC as a predictor and revealing how engagement at work is affected. It highlights the importance of boundary conditions such as gender and PCB. It is one of the first to assess the relationship between WFC, WLB, PCB and work engagement among construction professionals in India.

The purpose of this paper is to examine the impact of transformational leadership (TL) on organizational commitment (OC) with the mediating role of organizational justice (OJ) in the higher education (HE) sector in Syria.

The data were collected from 502 employees from six HE institutions. Two measures of organizational outcomes were selected for this study, namely, job satisfaction (JS) and OC. Using structural equation modelling (SEM), the authors tested four alternative models to indicate the relationship between leadership and organizational outcomes.

TL has both direct and indirect effects on OC through interactional justice (IJ). TL has an impact on JS through procedural justice (PJ) and IJ as intermediate variables, while transactional leadership (TrL) has an impact on JS through distributive justice (DJ). The three types of OJ have an impact on OC through JS. The authors found that the national culture may not influence the impact of the leader in the current globalization context, as the results were similar to the Western studies.

The findings of the study provide managers of the HE sector with insights into the formations of employees’ fairness perceptions, and with some guidelines for managing employees by documenting OJ to draw positive attitudinal and behavioral responses from employees.

While most previous research has focused on exploring the relationship between leadership and OJ or between OJ and JS in the business sector, the study, however, seeks in addition, to pinpoint the effect of OJ as a mediate variable between the leadership and JS and OC in HE.

Due to the environmental concerns in our society, governments are moving towards green purchasing. However, public sector organizations have substantial internal problems. By using a theory of natural resource-based view, this study aimed to analyse the influence of leadership styles and innovation capabilities on green purchasing in the public sector organizations of a developing economy.

Data was collected from 199 purchasing professionals of public sector organizations, and hypotheses were tested through a quantitative method using partial least square-structural equation modelling with the help of SmartPLS version 4 to validate the measurement model.

This study identified that transformational leadership and delegation style of leadership have a significant and positive effect on innovation capability and green purchasing. Similarly, innovation capability mediates the relationship between leadership styles and green purchasing. However, transformational leadership found a more substantial effect on innovation capability and green purchasing than the delegation leadership style.

Results provide insight into the role of leadership styles in green purchasing and innovation capabilities in public sector organizations. Thus, addressing the important issues of how leadership styles and innovative capabilities (IC) can improve green culture, specifically green purchasing, to enhance ecological sustainability.

Results provide insight into the role of leadership styles in green purchasing and innovation capabilities in public sector organizations. Thus, it addresses how leadership styles and IC can improve green culture, specifically green purchasing, to enhance ecological sustainability.

The poor quality of construction work in war-affected regions is a significant issue. The large-scale destruction to the existing infrastructure from the war necessitates cost and time-efficient delivery of construction projects during and post-war to bring normalcy to affected lives and places. Consequently, there is always a tendency to finish construction projects in the shortest possible time on a limited budget without following the proper quality management processes. However, the poor quality of construction projects continues to affect the country's development, growth, credibility, reputation, and public safety for several years after the war. To this end, the present study was conducted to evaluate the significant attributes and factors contributing to the poor quality of construction projects in the war-affected Afghan construction sector.

A total of 31 attributes influencing construction project quality were ranked based on 110 completed survey responses collected from Afghan construction professionals. Moreover, independent samples t-test, Spearman's rank correlation test, and exploratory factor analysis were conducted.

The study found a moderate consensus between clients and contractors on attributes' rankings. In addition, the independent samples t-test showed statistically significant differences in means values of responses from clients and contractors for eight attributes. Based on factor analysis, 19 important attributes (median value greater than or equal to four) were classified into 4 latent factors – (1) poor-quality assurance and control, (2) unethical practices, (3) design and drawing errors, and (4) knowledge and skills gap.

Evaluating the factors affecting the quality of construction projects will help clients, government departments, and construction practitioners improve the construction quality management practices. The findings will also inform the policies and procedures of international aid providers.