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This paper aims to present a hybrid machine learning algorithm for additive manufacturing (AM) design feature recommendation during the conceptual design phase.

In the proposed hybrid machine learning algorithm, hierarchical clustering is performed on coded AM design features and target components, resulting in a dendrogram. Existing industrial application examples are used to train a supervised classifier that determines the final sub-cluster within the dendrogram containing the recommended AM design features.

Through a case study of designing additive manufactured R/C car components, the proposed hybrid machine learning method was proven useful in providing feasible conceptual design solutions for inexperienced designers by recommending appropriate AM design features.

The proposed method helps inexperienced designers who are newly exposed to AM capabilities explore and utilize AM design knowledge computationally.

This paper aims to propose methods to evaluate the characteristic length of the melt pool for accurate fabrication and to identify the optimal process parameters in the selective laser melting process.

Specimens with the types of the scans by controlling the degree of the overlap with hatch spacing are fabricated. The scan modes are classified by statistically analyzing the results of hardness tests. According to the classification of the scans, the evaluation methods are proposed based on the observation of the shape of the solidified melt pool.

The control of the hatch spacing can reproduce all modes of the scan conditions, and hardness can be used to classify the scan modes.

The proposed evaluation methods are based on the analysis of the experimental observation so that they can be easily used for the real evaluation.

Springs are an integral part of mechanisms and can benefit from additive manufacturing’s (AM) increased design freedom. Given the limited literature on the subject, the purpose of this paper is to develop guidelines for fabricating helical springs using three-dimensional (3D) printing.

Polylactic acid (PLA) is the main material investigated, with ULTEM™ 9085 used as a comparison. The experimental procedure is to vary the spring parameters, print the springs and test them in tension or compression using constant velocity. Plots of the force and displacement are used to measure the linear and post-deformation spring constants. Loading of the springs is done both to breakage and cyclically. Cyclic loading is also used to observe the plastic behaviour of the springs. Parameters that are varied include wire and coil diameters, pitch, wire cross-section, in-fill and layer height.

A square wire cross-section is used, instead of a circle because it produces more consistent coils. In-fills make no significant difference in the elastic stiffness of the springs but the mono in-fill breaks at a greater extension, so it is recommended. Tension and compression springs are confirmed to behave the same when in the elastic regime. ULTEM™ 9085 produces consistently weaker springs compared to PLA. Variation of layer height shows that thinner layers increase the stiffness of the springs.

This study investigates the behaviour of 3D printed helical springs in tension and compression. Three guidelines are created: square wire cross-section, mono-directional in-fill and thin layers are recommended.

The 1997-98 financial crisis has had a profound effect on how East Asian economies the role of the IMF and its strategic interests relative to those of the United States in the international financial regime. It has prompted them to create a regional mechanism for financial and monetary cooperation, ranging from deeper policy dialogue and surveillance, to a system of financial cooperation, and common exchange rate arrangements. This paper analyses the economic and strategic motivations behind this and outlines recent developments in financial cooperation in East Asia to provide possible directions for the future.

A network of bilateral swap arrangements under the Chiang Mai Initiative(CMI) needs stronger policy dialogue and surveillance to develop into a regional financing facility, a sort of East Asian IMF. The facility plays a role as an regional lender of last resort, providing short-term funds to a member country facing a temporary liquidity shortage and for market intervention to stabilize foreign exchange rate. East Asian countries need to achieve regional exchange rate stability. In the long run, the region may develop a common currency arrangement, but it cannot be expected in the very near future because there is no convergence of macroeconomic conditions, economic structure and systems. A realistic approach would be for East Asian developing countries to adopt a currency basket system to minimize the impact of dollar/yen exchange rate volatility on their economies. Strong political will and a vision for regional integration will be required to introduce it.

The purpose of this paper is to understand how Design for Additive manufacturing Knowledge has been developing and its significance to both academia and industry.

In this paper, the authors use a bibliometric approach to analyse publications from January 2010 to December 2020 to explore the subject areas, publication outlets, most active authors, geographical distribution of scholarly outputs, collaboration and co-citations at both institutional and geographical levels and outcomes from keywords analysis.

The findings reveal that most knowledge has been developed in DfAM methods, rules and guidelines. This may suggest that designers are trying to learn new ways of harnessing the freedom offered by AM. Furthermore, more knowledge is needed to understand how to tackle the inherent limitations of AM processes. Moreover, DfAM knowledge has thus far been developed mostly by authors in a small number of institutional and geographical clusters, potentially limiting diverse perspectives and synergies from international collaboration which are essential for global knowledge development, for improvement of the quality of DfAM research and for its wider dissemination.

A concise structure of DfAM knowledge areas upon which the bibliometric analysis was conducted has been developed. Furthermore, areas where research is concentrated and those that require further knowledge development are revealed.

This study examines the role of meaningful work in mediating the relationship between employees’ perceptions of corporate social responsibility (CSR) and innovative behavior. This study further examines how co-worker support, both instrumental and emotional, moderates the meaningful work–innovative behavior relationship.

Utilizing survey data from 355 employees in South Korea with a two-wave longitudinal design, path modeling with the M-plus PROCESS macro was performed to analyze the mediation and second-stage moderated mediation effects.

The results showed that the relationship between employee CSR perceptions and innovative behavior was mediated by meaningful work. Co-worker instrumental support strengthened the meaningful work–innovative behavior relationship, whereas co-worker emotional support had no significant moderating effect. The three-way interaction analysis indicated that the meaningful work–innovative behavior relationship was weakest when co-worker instrumental support was low. Additionally, instrumental support by co-workers moderated the indirect effect of CSR perceptions on innovative behavior via meaningful work.

This research contributes to the literature on CSR perceptions and meaningful work. Our focus on meaningful work as a key psychological mechanism provides insights into how and why employee CSR perceptions promote desirable outcomes including innovative behavior, an underexplored yet important outcome. Furthermore, by identifying co-worker instrumental support as a significant boundary condition, this study contributes to a more nuanced understanding of the social context that promotes innovative behavior.

While the origin of Korean Industrial Relations goes back 150 years when the country opened its seaports to foreign countries, it didn’t emerge as a field of study until 1950s when academics began to write books and papers on the Korean labor movement, labor laws, and labor economics. In this paper, we sketch this history and describe important events and people that contributed to the development of industrial relations in Korea. Korean industrial relations in the early 20th century were significantly distorted by the 35-year-Japanese colonial rule (1910–1945). After regaining its independence, the U.S. backed, growth-oriented, military-based, authoritarian Korean government followed suit and consistently suppressed organized labor until 1987. Finally, the 1987 Great Labor Offensive allowed the labor movement to flourish in a democratized society. Three groups were especially influential in the field of industrial relations in the early 1960s: labor activists, religious leaders, and university faculty. Since then, numerous scholars have published books and papers on Korean industrial relations, whose perspectives, goals, and processes are still being debated and argued. The Korean Industrial Relations Association (KIRA) was formed on March 25, 1990 and many other academic and practitioner associations have also come into being since then. The future of industrial relations as a field of study in Korea does not seem bright, however. Issues regarding organized labor are losing attention because of a steadily shrinking unionization rate, changing societal attitude toward labor unions, and the enactment of new and improved laws and regulations regarding employment relationships more broadly. Thus, we suggest that emerging issues such as contingent workers, works councils and tripartite partnership, conflict management, and human rights will be addressed by the field of industrial relations in Korea only if this field breaks with its traditional focus on union and union–management relations.

After the Korean War, South Korean politics was dominated by national security concerns. Reversing Carl von Clausewitz's well-known dictum, in South Korea, “politics is the continuation of war by other means.” Until the late 1980s, politics in South Korea was far from democratic. South Korea had five direct presidential elections (1987, 1992, 1997, 2002, and 2007) and six national assembly elections (1988, 1992, 1996, 2000, 2004, and 2008) after the democratic transition of 1987. In 1992, a civilian candidate, Young Sam Kim, was elected president. Young Sam Kim (1993–1998) prosecuted and punished former generals turned presidents Doo Hwan Chun (1980–1988) and Tae Woo Roh (1988–1993) for corruption, mutiny and treason in 1995. Dae Jung Kim (1998–2003) was elected president in 1997. For the first time in South Korean political history, regime change occurred between a ruling party and an opposition party.

In this chapter, the change and continuity of civil–military relations through the fluctuating dynamics of the democratic transition and consolidation in South Korea is examined. A positive consolidation of democratic reform is one that, while securing indisputable civilian supremacy, grants the military enough institutional autonomy for the efficient pursuit of its mission. Civilian supremacy should be institutionalized not only by preventing military intervention in civilian politics but also by ensuring civilian control over the formation and implementation of national defense policy.

In sum, despite three terms of civilian presidency, civilian supremacy has not yet fully institutionalized. Although significant changes in civil-military relations did occur after the democratic transition, they were not initiated by elected leaders with the intention of establishing a firm institutional footing for civilian supremacy. South Korea's political leaders have not crafted durable regulations and institutions that will sustain civilian control over the military.

More than six decades, Korea is still divided. The most highly militarized zone in the world lies along the demilitarized zone. How to draw the line prudently between seeking national security and promoting democracy shall be the most delicate task facing all the civilian regimes to come in South Korea. That mission will remain challenging not only for civilian politicians but also for military leaders.

This study examined the effects of organizational justice and citizen respect to support for democratic policing through self-legitimacy among South Korean police officers.

The authors used survey data from 467 South Korean police officers in 2022. Structural equation model analysis was used to examine relationships between each variable.

This study found a positive relationship between organizational justice and self-assessed legitimacy. Also, citizen respect had a positive relationship with both police officers' self-assessed legitimacy and audience legitimacy. Self-assessed legitimacy had a significant effect on support for democratic policing, while perceived-audience legitimacy did not have a significant effect on support for democratic policing.

The current study provides evidence that self-legitimacy affects supporting democratic policing in a non-Western democracy. Additionally, to the best of our knowledge, this study is the first to examine the role of police self-legitimacy as a link between organizational justice and citizen respect and the intended behaviors of police officers toward citizens.

The purpose of this paper is to examine how the risk of war aroused by North Korea’s threatening actions trigger strategic responses from US multinational enterprises (MNEs) operating in South Korea. The authors compare two competing perspectives of real options and risk diversification to see which prevails when US MNEs are facing risk of war.

The authors hand collected news articles regarding North Korea’s threatening actions that may trigger strategic responses from MNEs operating in South Korea. The authors use archival data of US MNEs to verify our results.

Empirical tests of the two competing perspectives reveal that US MNEs adopt the risk diversification strategy when threatened by the risk of war. However, as MNEs have more available foreign markets outside the host country that is at risk of war, MNEs tend to take an operational flexibility approach more seriously and shift their productions to the remaining global operations. The ownership structure of the subsidiary does not appear to have significant effect on US MNEs’ strategic risk management.

This paper compares two perspectives, namely, real options and risk diversification, to observe how US MNEs treat their subsidiaries when facing risk of war in South Korea.