Young Jin Shin, Ebrahim Farrokh, Jaehoon Jung, Jaewon Lee and Hanbyul Kang
Despite the many advantages this type of equipment offers, there are still some major drawbacks. Linear cutting machine (LCM) cannot accurately simulate the true rock-cutting…
Abstract
Purpose
Despite the many advantages this type of equipment offers, there are still some major drawbacks. Linear cutting machine (LCM) cannot accurately simulate the true rock-cutting process as 1. it does not account for the circular path along which tunnel boring machine (TBM) disk cutters cut the tunnel face, 2. it does not accurately model the position of a disk cutter on the cutterhead, 3. it cannot perfectly replicate the rotational speed of a TBM. To enhance the knowledge of these issues and in order to mimic the real rock-cutting process, a new lab testing equipment was developed by Hyundai Engineering and Construction.
Design/methodology/approach
A new testing machine called rotary cutting machine (RCM) is designed to simulate the excavation process of hard-rock TBMs and includes features such as TBM cutterhead, RPM simulation, constant normal force mode and constant penetration rate mode. Two sets of tests were conducted on Hwandeung granite using different disk cutter sizes to analyze the cutting forces in various excavation modes. The results are analyzed using statistical analysis and dimensional analysis. A new model is generated using dimensional analysis, and its results are compared against the results of actual cases.
Findings
The effectiveness of the new RCM test was demonstrated in its ability to apply various modes of excavation. Initial analysis of chip size revealed that the thickness of the chips is largely dependent on the cutter spacing. Tests with varying RPM showed that an increase in RPM results in an increase in the normal force and rolling force. The cutting coefficient (CC) demonstrated a linear correlation with penetration. The optimal specific energy is achieved at an S/p ratio of around 15. However, a slightly lower S/p ratio can also be used in the design if the cutter specifications permit. A dimensional analysis was utilized to develop a new RCM model based on the results from approximately 1200 tests. The model's applicability was demonstrated through a comparison of TBM penetration data from 26 tunnel projects globally. Results indicated that the predicted penetration rates by the RCM test model were in good agreement with actual rates for the majority of cases. However, further investigation is necessary for softer rock types, which will be conducted in the future using concrete blocks.
Originality/value
The originality of the research lies in the development of Hyundai Engineering and Construction’s advanced full-scale laboratory rotary cutting machine (RCM), which accurately replicates the excavation process of hard-rock tunnel boring machines (TBMs). The study provides valuable insights into cutting forces, chip size, specific energy, RPM and excavation modes, enhancing understanding and decision-making in hard-rock excavation processes. The research also presents a new RCM model validated against TBM penetration data, demonstrating its practical applicability and predictive accuracy.
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Jaewon Lee and J. Martin Corbett
To examine the mechanisms through which downsizing affects employees' affective commitment to the organization in two Korean banks.
Abstract
Purpose
To examine the mechanisms through which downsizing affects employees' affective commitment to the organization in two Korean banks.
Design/methodology/approach
A total of 910 questionnaires were completed by bank employees. Data was analysed using hierarchical regression and LISREL path analysis techniques. Twenty semi‐structured interviews were also conducted.
Findings
The results show that the more severe the extent of downsizing, the lower employees' affective commitment to the organization. Moreover, downsizing has an impact on employees' affective commitment to the organization through several of the daily work experiences of employees. Thus, downsizing affects employees' affective commitment to the organization both directly and indirectly. However, its indirect impact is much stronger.
Research limitations/implications
The research was conducted in Korea and may have limited generalizability to Western cultures.
Practical implications
Sympathetic management of downsizing can minimize the negative impact on the affective commitment of surviving employees.
Originality/value
This paper offers insights into organizational commitment in a (relatively under‐researched) Korean context.
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Myoung-Soung Lee and Jaewon Yoo
This study investigated the influence of ambiguous customer expectations and customer demandingness, which reflect hindrance and challenge demands, on the boundary spanning…
Abstract
Purpose
This study investigated the influence of ambiguous customer expectations and customer demandingness, which reflect hindrance and challenge demands, on the boundary spanning behaviors (BSBs) of frontline bank employees (FBEs) through person-job fit and work engagement. It also examined the moderating effect of customer stewardship between job demands and work engagement.
Design/methodology/approach
Data of 296 FBEs in the retail banking industry in the Republic of Korea were collected through an online survey and analyzed.
Findings
Ambiguous customer expectations acted as hindrance demands and negatively affected FBEs' psychological process. Additionally, customer demandingness positively affected FBEs' psychological process as challenge demands. Moreover, person-job fit and work engagement improved the BSBs of FBEs as a psychological motivation process. Lastly, customer stewardship buffered the negative influence of ambiguous customer expectations on work engagement while strengthening the positive influence of customer demandingness on work engagement.
Originality/value
This study contributes to the marketing literature by presenting customer-related characteristics influencing the BSBs of FBEs and exploring the psychological response processes. First, this study presents empirical evidence that ambiguous customer expectations and customer demandingness play the role of hindrance and challenge demands, respectively. Second, it confirms that customer-related characteristics affect the BSBs of FBEs through psychological processes. Finally, it enriches the authors' understanding of customer stewardship as a job resource by exploring the role of customer stewardship in moderating the relationship between different types of job demands and work engagement.
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Jewon Lyu, Kim Hahn and Hyun-Joo Lee
Fashion products such as clothes, accessories, bags and footwear created using 3D printed technology are referred to as 3D printed fashion (3DPF) products. This study investigates…
Abstract
Purpose
Fashion products such as clothes, accessories, bags and footwear created using 3D printed technology are referred to as 3D printed fashion (3DPF) products. This study investigates consumers' motivation to purchase 3DPF products. In particular, this study adopts a multi-dimensional approach to explore the effects of personality-related traits such as innate, domain-specific and actualized innovativeness, as well as examine the effects of perceptions toward 3D printing technology (3DPT) (i.e. perceived security risk, performance expectancy). Based on the concepts of consumer innovativeness and the Unified Theory of Acceptance and Use of Technology (UTAUT), the authors expect the effects of consumers' innovativeness and perception of 3DPT and confirm its significant effects on a positive attitude toward 3DPF products and future purchase intention of 3DPF products.
Design/methodology/approach
A quantitative research design (i.e. survey) is utilized to examine the suggested relationships and application of existing theory in this study. All measurement items are adapted from previous literature and use a Likert-scale. The authors examined a total of 326 responses using a series of statistical analyses, including descriptive statistics, structural equation modeling and conditional process modeling.
Findings
The results of this study confirmed that innate and domain-specific innovativeness are critical antecedents of creating a positive attitude toward using 3DPF products through perceptions toward 3DPT. In addition, 3DPF innovativeness, as actualized innovativeness, was validated to strengthen the relationship between personal innovativeness and attitude, providing evidence that innovation-related traits can predict behaviors. Interestingly, technological innovativeness was not found to be a predictor of perceived security risk. It may be due that 3DPF products are still novel to consumers.
Research limitations/implications
The study participants were people who were interested in technology, not consumers who had prior experience with using 3DPF products. Future studies are encouraged to include consumers who have actually purchased or used 3DPF products.
Practical implications
The findings of this study indicate that consumers' use of new technology is determined by personality and interest in specific product categories. Practitioners may use this information to segment/target consumer groups to introduce a new/unfamiliar product.
Originality/value
The findings of this study contribute to the existing literature on consumer adoption of innovation by combining two approaches, the hierarchy of consumer innovativeness and the UTAUT, in the context of advanced technology adoption behavior.
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Myoung-Soung Lee and Jaewon Yoo
This study investigated the effects of social capital on frontline bank employee's adaptive selling behavior via the psychological process. Frontline bank employees' positive…
Abstract
Purpose
This study investigated the effects of social capital on frontline bank employee's adaptive selling behavior via the psychological process. Frontline bank employees' positive social relationships enhance their perception of the work environment and encourage work engagement. With the multiple mediation model, both internal and external social capital have direct and indirect influence on the frontline bank employee's adaptive selling behavior.
Design/methodology/approach
Data for this study were collected from a cross-sectional sample of retail banking industry in Korea. Specifically, using two-step procedures, employees of financial service or insurance sales department in banks were selected and online survey questionnaires were distributed to them. Data from 330 employees were collected and analyzed.
Findings
The results of this study showed how social capital affects frontline bank employees' person–job fit as a cognitive psychological process, leading to work engagement as an emotional psychological process and, in turn, more adaptive selling behavior. Using multiple mediation analysis, the results showed that work engagement on its own exerts a mediating effect on social capital, whereas a person–job fit does not.
Research limitations/implications
This study applied both aspects of the social capital concept by dividing it into internal and external social capital, and exploring each separately. This study examined the influence on psychological processes and behavioral response by distinguishing between the two forms of social capital. Second, this study expands the previous studies by introducing social capital as an antecedent factor of frontline bank employees' adaptive selling behavior. Finally, this study explains how frontline bank employees' relational resources (i.e. social capital) influence their emotional aspect (i.e. work engagement) and cognitive aspect (i.e. person–job fit), which ultimately influence performance-driven behavior (i.e. adaptive selling behavior).
Practical implications
This research showed the importance of hiring frontline bank employees with excellent social capital capabilities. Furthermore, this study underscored the fact that organizations require preparing and providing practical management methods that can improve the social capital of their current frontline employees. Last, organization need to design the job in a way that innately improves frontline employees' social capital. Therefore, these jobs provide many opportunities for frontline bank employees to use their ability to build relationships in their interactions with customers and make practical decisions to achieve job performance.
Originality/value
This study improved our understanding regarding the importance of employees' social capital by revealing the psychological process of how frontline bank employees' social capital affects adaptive selling behavior. Second, this study expands on the literature by introducing internal and external social capital as an antecedent factor affecting the adaptive selling behavior of frontline bank employees. Furthermore, this study advances understanding on the manner in which relational resources of frontline bank employees (i.e. social capital) influence the emotional (i.e. work engagement) as well as the cognitive aspects (i.e. person–job fit), which ultimately influence performance-driven behavior (i.e. adaptive selling behavior).
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Jaewon Choi and Jieun Lee
The authors estimate systemic risk in the Korean economy using the econometric measures of commonality and connectedness applied to stock returns. To assess potential systemic…
Abstract
The authors estimate systemic risk in the Korean economy using the econometric measures of commonality and connectedness applied to stock returns. To assess potential systemic risk concerns arising from the high concentration of the economy in large business groups and a few export-oriented sectors, the authors perform three levels of estimation using individual stocks, business groups, and industry returns. The results show that the measures perform well over the study’s sample period by indicating heightened levels of commonality and interconnectedness during crisis periods. In out-of-sample tests, the measures can predict future losses in the stock market during the crises. The authors also provide the recent readings of their measures at the market, chaebol, and industry levels. Although the measures indicate systemic risk is not a major concern in Korea, as they tend to be at the lowest level since 1998, there is an increasing trend in commonality and connectedness since 2017. Samsung and SK exhibit increasing degrees of commonality and connectedness, perhaps because of their heavy dependence on a few major member firms. Commonality in the finance industry has not subsided since the financial crisis, suggesting that systemic risk is still a concern in the banking sector.
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Ziyou Jiang and Jewon Lyu
Augmented reality (AR) provides consumers with added value by allowing them to experience products via mobile devices. An increasing number of brands have adopted AR apps, but…
Abstract
Purpose
Augmented reality (AR) provides consumers with added value by allowing them to experience products via mobile devices. An increasing number of brands have adopted AR apps, but little is known about how consumers respond to AR app attributes or what motivates them to use luxury brand AR apps. To fill this gap, this study aims to use the stimulus-organism-response (S-O-R) model to examine how AR app attributes (i.e. interactivity and virtuality) and customer-based brand equity (CBBE) (i.e. brand awareness and brand image) of luxury brands affect consumers’ behavioral intention to share about the app and use it for future purchases.
Design/methodology/approach
Participants were recruited using a quantitative online survey (n = 214) and asked to use the Gucci mobile AR app before completing the survey. Partial least squares structural equation modelling (PLS-SEM) was used to analyze the data. All measures were adapted from existing literature.
Findings
Findings indicate that AR app attributes lead to positive consumer experience, in turn, creating behavioral intention, while CBBE partially leads to positive consumer perceptions. Post hoc analysis confirms that consumers’ perceived values mediate the relationship between AR app attributes and consumers’ attitudes toward a luxury brand AR app.
Originality/value
Theoretically, this study expands the application of the S-O-R model along with brand equity to AR adoption and luxury retail by demonstrating the intricate mechanism of how AR app attributes and CBBE promote consumers’ behavioral intentions toward luxury brand AR apps. Practitioners may create more interactive and immersive virtual product demonstrations and focus on establishing the overall brand image.
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Toan Van Nguyen, Minh Hoang Do and Jaewon Jo
To follow and maintain an appropriate distance to the selected target person (STP), the mobile robot is required to have capabilities: the human detection and tracking and an…
Abstract
Purpose
To follow and maintain an appropriate distance to the selected target person (STP), the mobile robot is required to have capabilities: the human detection and tracking and an efficient following strategy with a smooth manner that does not appear threatening to the STP and surroundings. The efficient following strategy must integrate the STP position and the obstacle information to achieve smooth and safe human-following behaviors, especially in unknown environments where robot does not have understandings in advance. The purpose of this study is to propose a robust-adaptive-behavior strategy for mobile robots.
Design/methodology/approach
This paper presents a robust-adaptive-behavior strategy (RABS) based on the fuzzy inference mechanism to help the robot follow the STP effectively in various unknown environments with the real-time obstacle avoidance, both indoor and outdoor and on different robot platforms. In which, the traversability of robots’ unknown surrounding environments is analyzed by using the STP position and the obstacle information obtained from the two dimensional laser scan, whose purpose is to choose the highest-traversability-score direction (HTSD) and an adaptive-safe-following distance (ASFD). Then, the HTSD, the ASFD and the current velocity of the robot are considered as inputs of the fuzzy system to adjust its velocity smoothly.
Findings
The proposed RABS is verified by a set of experiments using a real big-heavy autonomous mobile robot (BH-AMR), with the dimension 0.8 × 1.2 (m), weight 150 (kg), full-load 500 (kg), aiding smart factories. The obtained results have shown that the proposed RABS equips the BH-AMR with the ability to follow the STP smoothly and safely even when the robot is moving at the maximum speed 1.5 (m/s).
Research limitations/implications
In this paper, the autonomous mobile robot considers all environments as unknown even when it is working in mapped environments. This limitation is presented clearly in the future works section.
Practical implications
This proposed method can be used to help the autonomous mobile robot support persons in factories, hospitals, restaurants, supermarkets or at the airports.
Originality/value
This paper presents a RABS, including three new features: a fuzzy-based solution to help human-following robots maintain an appropriate distance to the STP safely and smoothly with the maximum velocity 1.5 (m/s); the proposed fuzzy-based solution, an adaptive vector field histogram and a new approach for the STP tracking is combined to follow the STP and avoid the collision simultaneously in unknown indoor and outdoor environments; the proposed RABS is considered for BH-AMRs (with the dimension 0.8 × 1.2 (m), weight 150 (kg), full-load 500 (kg)) to serve real tasks in smart factories.