10.1 INTRODUCTION [LO1]

There are many applications where structures or machine parts are subjected to significant changes in temperature, for example, turbine blades, high-speed rotating machinery, and boilers in thermal power plants. Large thermal stresses may be developed in such applications, and sometimes such stresses may exceed the yield limit. It is therefore necessary to make provisions in the design of components to avoid failure due to thermal stresses. If the ends of a rod or any other machine parts are rigidly fixed such that the expansion or compression is prevented and the temperature is changed, tensile or compressive stress would be set up, and in simple terms, these stresses are called thermal stresses. In a long steam pipe, expansion joints are sometimes inserted, and in bridges, one end may be rigidly fastened to the main structure while the other end rests on rollers to avoid thermal stresses. In simple terms, this may be demonstrated considering a rod of length l and cross-sectional area A fixed at both ends (Figure 10.1) and temperature is raised by ΔT. This would produce a thermal strain ∈t in the rod such that

where a is the coefficient of thermal expansion. Since the rod is not free to expand, a compressive stress σc would be developed in the rod, and this is given by

If the rise in temperature is significant, the rod may buckle, which is of serious consideration in the design of machine parts or structures. To avoid this, we need to find the critical force Pcr for buckling. Using the basic buckling criterion, this can be given for a column pin ended at both ends, by

where I is the least moment of inertia of the constant cross-section column (rod) and A is the cross-sectional area of the column.

The economic reforms of China in 1978 and Vietnam in 1986 have spurred the emergence of privately owned enterprises, leading to increased competition across state-owned and privately owned enterprises under communist authoritarian regimes. Upon joining the World Trade Organization (WTO), both countries faced unavoidable international competition, particularly excelling in labor-intensive manufacturing industries due to low labor costs. China’s pragmatic approach to market-oriented forces has resulted in a growth gap favoring China over Vietnam. Despite this, both nations have made significant economic strides, transitioning to fast-growing middle-income countries and reducing global inequality. The onset of the US–China trade war in 2018 has seen Vietnam emerge as a major beneficiary, challenging China’s dominance in labor-intensive manufacturing industries. This shift highlights the potential for hegemonic transitions in competition dynamics. Additionally, this chapter illuminates pre-reform competition in both countries, where shortages of goods led to resource competition among citizens – an aspect often overlooked in existing literature focused on market competition post-reform.

Little is known about how competitive attitudes differ between refugees and their host citizens. Study 1 investigated the relationship between refugee background and competitive attitudes, alongside demographic characteristics, social comparison concerns, and exposure to competition, using data from 190 North Korean refugees (NKRs) and 445 South Koreans (SKs). Refugee background and social comparison concerns had significantly more effect on competitive attitudes compared to other demographic characteristics and the ranking variable. In Study 2, cultural scores based on Hofstede’s theory were examined, alongside demographic factors, refugee background, and social comparison concerns. Refugee background and social comparison concerns showed stronger associations with competitive attitudes than cultural scores. Study 3 divided the sample into NKRs and SKs, revealing social comparison concerns’ predominant influence on competitive attitudes in both groups. However, the impact of the ranking variable varied between NKRs and SKs. These findings underscore the importance of understanding the experiences of refugees in shaping their competitive attitudes, from migration to resettlement.

Summarising how economists have historically studied families from the nineteenth century to the present, we recall that economists developed methodologies in response to how they imagined and constituted the problem of family poverty in different periods. In contemporary times, concerns for poverty-alleviation have increasingly featured concerns for justice across gender, race, and ethnicity. We also recall how family economists prioritised some social and political problems over others, leaving significant injustices uncontested. These findings encourage reflection on how we define the social problems of families today. Describing the small body of economics on the relation between family behaviour and a sustainable biosphere, the book closes with a provocation. If each period of family economics has relied on an act of imagination to formulate the family-relevant social problems worthy of consideration, how might we constitute the problem of family poverty today, consistent with justice across gender, race, and ethnicity, while also tackling the very urgent need for a biosphere capable of supporting human life? How might we imagine living well and dying well today, on a damaged planet undergoing ecosystem collapse? And how might economists assist families to tackle this problem, today?

Using the World Value Survey from Wave 2 (1989–1993) to Wave 7 (2017–2020), Study 1 demonstrates that individuals in individualistic regions exhibit more anti-competition attitudes compared to those in collectivist regions. Additionally, individuals in authoritarian, socialist, and collectivist Asian regions show the highest level of pro-competition attitudes, followed by those in democratic, capitalist, and individualistic Western regions and those in democratic, capitalist, and collectivist Asian regions. Study 2 reveals that competition is more likely to be endorsed by individuals who prioritize the individual’s responsibility over the government’s responsibility, value private ownership of businesses over government ownership of businesses, emphasize hard work for success, and prefer income incentives over income equality. Moreover, individuals with higher levels of materialism and self-determination are also inclined to endorse competition. Notably, variations exist in the relationship between individual difference variables and attitudes toward competition among the regions.

Why and how economists have historically studied families is not well understood, neither by those in the discipline, nor by scholars studying families in neighbouring fields like sociology, anthropology, and philosophy. This lack derives from a mistaken view that family economics began in the 1960s when price theory was applied to family behaviour. It is also due to the narrowing of economics from the 1940s in the US, when social reform and advocacy work shifted to the discipline’s periphery. Affirming a contemporary need for gender-inclusive language, while using terms that access historical understandings, the book’s first goal is to show that economists developed methodologies for studying families as a function of how they conceptualised family poverty in different periods. Four historical phases are identified, with economists studying nineteenth-century deficits in family labour productivity in Britain and Europe, inadequacies in low-income family consumption in interwar America, underinvestment in human capital by a post-war ‘underclass’, and gendered injustices in resource distribution experienced by lone mothers, by women and girls in poor global South families, and by queer families. The book’s second goal is to show how family economists prioritised some social problems over others, allowing certain injustices to remain uncontested.

Since the North Korean Famine in the mid-1990s, survivors have turned to cross-border activities for sustenance, evolving into commercial activities in black markets known as jangmadang. With the collapse of the socialist Public Distribution System, the majority of North Koreans now rely on these black markets to earn money and meet their basic needs. However, such commercial activities for personal gain are illegal in the country, symbolizing the emergence of North Korea’s hidden market economy. This hidden economy is characterized by various types of “shadowy private enterprises (SPEs),” ranging from entities officially registered as state-owned enterprises but run by private individuals to home-based enterprises. These SPEs sustain their operations and evade punishment by bribing bureaucrats. However, systematic corruption poses threats to the survival, safety, and well-being of marginalized groups who struggle to pay bribes, exacerbating inequality between privileged and unprivileged segments of society. Consequently, the hidden economy engenders various forms of competition, spanning from market competition to an invisible competition for safety and wellbeing.

12.1 INTRODUCTION [LO1]

There are in general two approaches to solving equilibrium problems in solid mechanics: Eulerian and Lagrangian. The first approach deals with vectors such as force and moments, and considers the static equilibrium and compatibility equations to solve the problems. In the second approach, scalars such as work and energy are used, and here solutions to problems are based on the principle of conservation of energy. There are many situations where the second approach is more advantageous, and here some powerful methods, such as the method of virtual work, based on this approach, are used.

Eulerian and Lagrangian approaches to solving solid mechanics problems are much more involved. However, here we have chosen to describe these in a simplified manner, which is suitable as a prologue to the present discussion on energy methods.

In mechanics, energy is defined as the capacity to do work, and this may exist in different forms. We are concerned here with elastic strain energy, which is a form of potential energy stored in a body on which some work is done by externally applied forces. Here it is assumed that the material remains elastic when work has been done so that all the energy is recoverable and no permanent deformation occurs. This means that strain energy U = work done. If the load is applied gradually in straining, the material load–extension graph is as shown in Figure 12.1, and we may write U = ½ Pδ.

The hatched portion of the load–extension graph represents the strain energy and the unhatched portion ABD represents the complementary energy that is utilized in some advanced energy methods of solution.

Physical education in the Soviet Union, initially focused on health and military readiness, shifted toward producing athletes for international competitions by the early 1950s, peaking in the 1970s/1980s. This shift led to increased investment in sport psychology. To analyze this history, particularly the use of sports to promote communist values, and challenge other political systems, I synthesized peer-reviewed articles using keywords like "Soviet Union," "sport(s) psychology," and "Puni." As social scientists, we decided to analyze this specific history with an emphasis on psychological theories to better understand how the Soviet Union’s communist ideology impacted scientific study within the Soviet Union and sports competition abroad. Thus, I explored the life of the most prominent sports psychologist in the Soviet Union, Avksenty Cezarevich Puni, and his theory of Psychological Preparation for Competition (PPC), which serves as an example of the Soviet Union’s approach to applied sports. Additionally, I examined how Soviet Olympic successes spurred investment in sports and sport psychology, reflecting efforts to compete with the West and asserting the superiority of communism.

The dominant assumptions positing a linear relationship among individualism, capitalism, competition, and inequality are often rooted in the perspectives of social scientists, whose focus is frequently confined to the West in modern times. I argue that these dominant assumptions have been formulated without sufficient opportunities or willingness to consider societies with cultures and systems different from those of the West. In this regard, this book challenges these dominant assumptions by presenting compelling counter-evidence that (1) competition occurs in every society throughout history whenever humans seek to survive and thrive; and (2) competition does not necessarily lead to inequality, but often serves as a tool to mitigate it, as competitions prevent absolute hegemony and allow individuals to challenge incumbent powers or privileged groups across cultures, systems, and eras. This closing chapter encourages readers to reassess their existing beliefs about the sources and consequences of competition and to strive for a deep understanding of competition arenas that they may choose to enter or inadvertently launch.

In the early twentieth century, changes in production targeted low-income family consumption with labour-saving domestic appliances and factory-produced clothing and shoes. Employment of maids declined. Women’s factory work increased. After the Great War, governments and housing producer groups tamed male-worker unrest with low-interest housing loans. Working-class families left shoddy inner-city tenement abodes for bright, practical homes in Midwest suburbs. White mothers returned to household production. Non-English-speaking families migrated into rural areas. Consequently, family economists like Hazel Kyrk, Elizabeth Hoyt, Margaret Reid, and others studied how to improve the consumption activities of low-income and farming families, a problem that intensified during the Great Depression. Methods included studies of family expenditure, calculations of the value of household production for family income, and the development of consumer price indices. Their pragmatism produced policies to secure adequate family budgets and consumer-friendly markets. However, they accepted gendered divisions of household–market labour, distancing themselves from the feminist organisations that had supported women through war with cooperative domestic labour. Differences in living standards between urban and rural families, and between white and non-white families, were mostly viewed as outcomes of family preference, and not as injustices. Methodologies did not reach the family consumption of Dustbowl evacuees.