Search results
1 – 10 of 627Lijie Ma, Xinhui Mao, Chenrui Li, Yu Zhang, Fengnan Li, Minghua Pang and Qigao Feng
The purpose of this study is to reveal the friction reduction performance and mechanism of granular flow lubrication during the milling of difficult-to-machining materials and…
Abstract
Purpose
The purpose of this study is to reveal the friction reduction performance and mechanism of granular flow lubrication during the milling of difficult-to-machining materials and provide a high-performance lubrication method for the precision cutting of nickel-based alloys.
Design/methodology/approach
The milling tests for Inconel 718 superalloy under dry cutting, flood lubrication and granular flow lubrication were carried out, and the milling force and machined surface quality were used to evaluate their friction reduction effect. Furthermore, based on the energy dispersive spectrometer (EDS) spectrums and the topographical features of machined surface, the lubrication mechanism of different granular mediums was explored during granular flow lubrication.
Findings
Compared with flood lubrication, the granular flow lubrication had a significant force reduction effect, and the maximum milling force was reduced by about 30%. At the same time, the granular flow lubrication was more conducive to reducing the tool trace size, repressing surface damage and thus achieving better surface quality. The soft particles had better friction reduction performance than the hard particles with the same particle size, and the friction reduction performance of nanoscale hard particles was superior to that of microscale hard particles. The friction reduction mechanism of MoS2 and WS2 soft particles is the mending effect and adsorption film effect, whereas that of SiO2 and Al2O3 hard particles is mainly manifested as the rolling and polishing effect.
Originality/value
Granular flow lubrication was applied in the precision milling of Inconel 718 superalloy, and a comparative study was conducted on the friction reduction performance of soft particles (MoS2, WS2) and hard particles (SiO2, Al2O3). Based on the EDS spectrums and topographical features of machined surface, the friction reduction mechanism of soft and hard particles was explored.
Details
Keywords
Safiya Sinclair and Gregory B. Fairchild
Jason has had a string of bad luck: he was fired from his job, his car got repossessed, he had to move back in with his mother when he was unable to make rent on his apartment…
Abstract
Jason has had a string of bad luck: he was fired from his job, his car got repossessed, he had to move back in with his mother when he was unable to make rent on his apartment, and his girlfriend dumped him. He is feeling unmotivated and discouraged, but also recognizes—at his mother's insistence—that he needs to start contributing to the household. Following his mother's orders, he heads to the local strip mall seeking employment.
How hard could it be to get a job, anyway?
Details
Keywords
Lars Mjøset, Roel Meijer, Nils Butenschøn and Kristian Berg Harpviken
This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial…
Abstract
This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial, populist and democratic pacts, suitable for analysis of state formation and nation-building through to the present period. The framework relies on historical institutionalism. The methodology, however, is Rokkan's. The initial conceptual analysis also specifies differences between European and the Middle Eastern state formation processes. It is followed by a brief and selective discussion of historical preconditions. Next, the method of plotting singular cases into conceptual-typological maps is applied to 20 cases in the Greater Middle East (including Afghanistan, Iran and Turkey). For reasons of space, the empirical analysis is limited to the colonial period (1870s to the end of World War 1). Three typologies are combined into one conceptual-typological map of this period. The vertical left-hand axis provides a composite typology that clarifies cultural-territorial preconditions. The horizontal axis specifies transformations of the region's agrarian class structures since the mid-19th century reforms. The right-hand vertical axis provides a four-layered typology of processes of external intervention. A final section presents selected comparative case reconstructions. To the authors' knowledge, this is the first time such a Rokkan-style conceptual-typological map has been constructed for a non-European region.
Details
Keywords
While most West European nations were formed around pre-existing entities that could be called “countries” before the modern age, this was not the case in the Middle East. Some…
Abstract
While most West European nations were formed around pre-existing entities that could be called “countries” before the modern age, this was not the case in the Middle East. Some entities, like Egypt, did have a clear political and cultural identity before colonialism, others, like Algeria, did not. This chapter discusses the four states of the Maghreb: Morocco, Algeria, Tunisia and Libya, through the perspective of “country creation” going into and coming out of colonial rule. We can see here two “models” of fairly similar types of historical development, one showing a gradual process through a protectorate period to relatively stable modern nations, another through violent conquest and direct colonization ending in violent liberation and military and wealthy but fragile states. The article asks whether these models for the history of country creation and the presence or absence of pre-colonial identities can help explain the modern history and nature of these states in the Arab Spring and the years thereafter. Then, a more tentative attempt is made to apply these models to two countries of the Arab east, Syria and Iraq. While local variations ensure that no model can be transferred directly, it can show the importance of studying the historical factors that go into the transition from geographical region to a country with people that can form the basis of a nation.
Details
Keywords
Diego Biondo, Dalton Alexandre Kai, Edson Pinheiro de Lima and Guilherme Brittes Benitez
While previous operations management literature acknowledges the positive influence of Lean and Industry (I4.0) on performance, recent studies examining the synergy between these…
Abstract
Purpose
While previous operations management literature acknowledges the positive influence of Lean and Industry (I4.0) on performance, recent studies examining the synergy between these two factors have produced inconsistent and contradictory results. Therefore, this study aims to provide a comprehensive understanding of the effect of Lean and I4.0 synergy on firm performance.
Design/methodology/approach
This study utilised a meta-analysis approach, examining 23 empirical studies exploring multiple effects of the Lean and I4.0 synergy on firm performance. Multiple subgroup analyses were conducted to assess the contradictory outcomes and identify in what conditions such synergy may achieve performance.
Findings
The results affirm the prevailing positivist perspective among most scholars regarding the positive influence of the Lean and I4.0 synergy on firm performance. However, the overall effect size derived from the studies indicates a weak relationship, suggesting that this synergy alone is not the sole determinant factor of firm performance. In addition, the subgroup analyses reveal the presence of contingent conditions that may affect the performance outcomes when integrating Lean and I4.0, as most effects exhibit a weak relationship.
Originality/value
This study represents the first meta-analysis investigating the relationship between the Lean and I4.0 synergy on firm performance. By shedding light on the contradictory effects often depicted in the operations management literature, this study provides a critical reflection for researchers who tend to adopt an overly optimistic view of such synergy.
Details
Keywords
Maria Krysfeldt, Jannick Friis Christensen and Thomas Burø
The paper discusses how the management of a sports and fashion company, which we refer to as NULMA, successfully applied the neo/normative control technology “karma organisation”…
Abstract
Purpose
The paper discusses how the management of a sports and fashion company, which we refer to as NULMA, successfully applied the neo/normative control technology “karma organisation” and gained employee engagement. Whereas other studies have documented employee resistance to organisational cultures when used for managerial control, our case demonstrates resistance to management practices that employees find inconsistent with the dominant karma culture.
Design/methodology/approach
The study is based on a six-year longitudinal organisational at-home ethnography conducted by one of the authors using methods of both participant and non-participant observation, semi-structured interviews and collaborative production of secondary data in the case organisation.
Findings
While our research shows that management can successfully apply neo/normative control which employees accept and support, we further show that employees mobilise the same values to resist management when it fails to deliver on the commitments and promises of the organisational culture.
Originality/value
The study contributes to the literature on organisational culture and, in particular, neo/normative control by theorising employee resistance as being by “accident”, by which we mean an inherent negative potentiality co-invented and released by managers establishing a “karma organisation”. Our theorising culminates in a discussion of the study’s implications for research and practice.
Details
Keywords
This chapter is focused on what we can learn from oppressive governance, in this case specifically relating to university governance in terms of vice chancellors and presidents…
Abstract
This chapter is focused on what we can learn from oppressive governance, in this case specifically relating to university governance in terms of vice chancellors and presidents, to the deputy vice chancellor and deputy president and down the ever-growing university hierarchy to deans and heads of schools and their deputies, from a Freirean perspective. Freire wrote at length about how leaders ‘controlled’ education and why they did so, but he also wrote at length about how governments control populations – himself being both a political prisoner and a person in exile to escape persecution. This chapter subsequently examines Freire's ideas around what techniques people employ to control populations and applies them to a higher education setting because the similarities are numerous and the tactics familiar.
In 2017, it was a challenge to assess the future of global trade. It was an open question whether the US financial crisis and the recession that it triggered would mark a turning…
Abstract
In 2017, it was a challenge to assess the future of global trade. It was an open question whether the US financial crisis and the recession that it triggered would mark a turning point for the liberal post–World War II world order. If one looked toward Europe, China, Latin America, and Japan, there was a flurry of activity. New trade agreements were being completed and pursued. In Washington, DC, on the other hand, President Donald Trump seemed set on ripping apart and/or renegotiating any trade deal the United States was ever part of.
This case explores Trump's opinions and emerging policy stance on trade, bilateralism, and the global economy, among others. It also gives an overview of the World Trade Organization (WTO) and the General Agreement on Tariffs and Trade (GATT) and asks whether the Trump presidency would constitute a major challenge to the WTO and what it stood for in 2017.
Details
Keywords
Yeva Nersisyan and L. Randall Wray
In this paper, the authors examine the causes of 2021–2023 inflation and evaluate whether raising interest rates is the right solution.
Abstract
Purpose
In this paper, the authors examine the causes of 2021–2023 inflation and evaluate whether raising interest rates is the right solution.
Design/methodology/approach
The authors evaluate both the macroeconomic (too much demand) and microeconomic (monopoly pricing and supply chains) explanations for the causes of inflation.
Findings
The authors argue that the spike in inflation is due to disrupted supply chains and corporations taking advantage of the situation to raise their prices. The aggregate demand stimulus from fiscal policy had all but played out by the time inflation arose, making it an unlikely cause of said inflation.
Originality/value
The authors' paper demonstrates that raising interest rates is the wrong solution to tackling the problem of inflation, especially since it's coming from the supply side.
Details