• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.12
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• pp.5782-5799
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• 2018

With the development of GPS and the popularity of mobile devices with positioning capability, collecting massive amounts of trajectory data is feasible and easy. The daily trajectories of moving objects convey a concise overview of their behaviors. Different social roles have different trajectory patterns. Therefore, we can identify users or groups based on similar trajectory patterns by mining implicit life patterns. However, most existing daily trajectories mining studies mainly focus on the spatial and temporal analysis of raw trajectory data but missing the essential semantic information or behaviors. In this paper, we propose a novel trajectory semantics calculation method to identify groups that have similar behaviors. In our model, we first propose a fast and efficient approach for stay regions extraction from daily trajectories, then generate semantic trajectories by enriching the stay regions with semantic labels. To measure the similarity between semantic trajectories, we design a semantic similarity measure model based on spatial and temporal similarity factor. Furthermore, a pruning strategy is proposed to lighten tedious calculations and comparisons. We have conducted extensive experiments on real trajectory dataset of Geolife project, and the experimental results show our proposed method is both effective and efficient.

• Journal of Power Electronics
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• v.19 no.1
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• pp.146-157
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• 2019

The inverter is an essential part of permanent magnet synchronous motor (PMSM) drive systems. The performance of an inverter is greatly influenced by its modulation strategy. Using a proper management of modulation strategies can guarantee high performance from a PMSM under various speed conditions. Switching between modulations is a pivotal technique that determines the performance of a PMSM. Most works on hybrid methods focus on two-level induction motors drive systems. In this paper, in order to improve the performance of PMSMs under various speed conditions, a hybrid method of a pulse width modulation (PWM) control scheme based on a neutral-point-clamped (NPC) three level topology was proposed. This hybrid PWM modulation comprised space vector PWM (SVPWM) and selective harmonic elimination PWM (SHEPWM). Under low speed conditions, the SVPWM is employed to cause the PMSM to start smoothly, and to obtain a rapid response from the control system. Under high speed conditions, the SHEPWM is employed to reduce the switching frequency and to eliminate particular current harmonics. Moreover, the harmonic characteristics of different modulations are analyzed to obtain a smooth transition between the SHEPWM and the SVPWM. Experimental and simulation results indicated the effectiveness of the proposed control method.

• Journal of Information Technology Applications and Management
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• v.25 no.4
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• pp.79-114
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• 2018

Although former scholarly studies mostly focus on exploring leadership effectiveness under the traditional hierarchical leader-subordinate relationship, the research of leadership performance for non-hierarchical organizational structures, particularly the mediating factors of higher-order goals, trust-in-leader, and self-efficacy have been ignored. This study, therefore, makes an attempt to ascertain the impacts of transformational leadership on the performance of subordinates through the mediating effects of higher-order goals, trust-in-leader, and self-efficacy and the differences of these effects in the context of multi-level marketing (MLM). Like the small-sample studies adopted by Barling, Weber, and Kelloway [1996], Barling, Slater, and Kelloway [2000] and Bass, Avolio, Jung, and Berson [2003], this study adopts a sample of 123 MLM distributors of an MLM company in Hong Kong, with a high response rate of 80.4%. The results indicate that the mediating effect of self-efficacy between transformational leadership and performance is significant under non-hierarchical organizational structures such as MLM in China.

• Journal of Industrial Convergence
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• v.15 no.1
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• pp.43-52
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• 2017

Robot refers to machines that recognize the external environment and assess the given situations in order to operate autonomously by imitating the manner in which humans behave. Although Korea still lacks global competitiveness, Korea, as the $4^{th}$ ranked robot manufacturing country in the world, is currently expanding the domains of robots from application in manufacturing to application in service provision. Accordingly, this study aims to analyze the factors for the success in entry into the cooperation robot market among various robotic markets in accordance with the literary research method in consideration for the importance of robot industry that could determine the future national competitiveness. The result of the analysis of the factors for the success in entry into the cooperation robot market, shows that factors including analysis of the trends in manufacturing robot market, strategy for benchmarking of the leading cooperation robot companies, activation of small and medium enterprise-centered cooperation robotic industry, excavation of demands for cooperation robots with focus on automobile, semiconductor and IT industries, utilization of the opportunities provided by government's robotic industry policies and standardization of cooperation robot components, etc. determine whether one will succeed in the market or not. Furthermore, it is believed that fortification of competitiveness of the manufacturing sector through the powerful policy support for the robotic industry at government level and policies on cultivation of new growth engine through specialization of the robotic areas closely related to daily life must be implemented concurrently because it is forecasted that competitiveness in robotics technology will become the criterion for national competitiveness in the future.

• Clinical and Experimental Pediatrics
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• v.64 no.5
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• pp.196-207
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• 2021

Over the last few decades, the rates of pediatric obesity have more than doubled regardless of sociodemographic categorization, and despite these rates plateauing in recent years there continues to be an increase in the severity of obesity in children and adolescents. This review will discuss the pediatric obesity mediated cardiovascular disease (CVD) risk factors such as attenuated levels of satiety and energy metabolism hormones, insulin resistance, vascular endothelial dysfunction, and arterial stiffness. Additionally, early intervention to combat pediatric obesity is critical as obesity has been suggested to track into adulthood, and these obese children and adolescents are at an increased risk of early mortality. Current suggested strategies to combat pediatric obesity are modifying diet, limiting sedentary behavior, and increasing physical activity. The effects of exercise intervention on metabolic hormones such as leptin and adiponectin, insulin sensitivity/resistance, and body fat in obese children and adolescents will be discussed along with the exercise modality, intensity, and duration. Specifically, this review will focus on the differential effects of aerobic exercise, resistance training, and combined exercise on the cardiovascular risks in pediatric obesity. This review outlines the evidence that exercise intervention is a beneficial therapeutic strategy to reduce the risk factors for CVD and the ideal exercise prescription to combat pediatric obesity should contain both muscle strengthening and aerobic components with an emphasis on fat mass reduction and long-term adherence.

• Journal of Internet Computing and Services
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• v.22 no.4
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• pp.99-110
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• 2021

Governments around the world are actively establishing strategies and initiatives to spread the use of artificial intelligence (AI), for AI is not a mere new technology, but is an innovative technology that brings about extensive changes in industrial and social structures and is a core engine that will lead the 4th Industrial Revolution. The South Korean government has also been paying attention to AI as a technology and tool for innovative growth, but its application to the industries is still rather sluggish. The government has prepared multifarious AI-related policies with the aim of constructing South Korea as an AI powerhouse, but there is no clear strategy on which detailed policies to implement first and which industries to apply AI preferentially. With these limitations of South Korea's AI policies in mind, this paper analyzed the priorities of industries in AI adoption and the priorities of AI-related national policies, using Delphi-AHP method for 30 top-level AI experts in South Korea. The results of analysis show that AI application is urgent and necessary in the fields of medical/healthcare, public and safety, and manufacturing, which seems to reflect the peak of the COVID-19 crisis in the second half of 2020 at the time of the investigation. And it turns out that policies related to AI talent cultivation, data, and R&D investment are important and urgent above all in order for organizations to apply AI. This suggests that strategies are required to focus limited national resources on these industries and policies first.

• Journal of Distribution Science
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• v.19 no.2
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• pp.15-24
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• 2021

Purpose: The research is to find out the perception of consumers for the convenience store (c - store) image in an emerging market, with a sample from Ho Chi Minh City. Research design, data, and methodology: Data were collected using a 24 - item structured questionnaire into six factors, namely: store atmospheric, merchandise, supplementary service, customer convenience, sales personnel, promotion. Five hundred consumers shopped at the different c - stores were collected for a multidimensional scaling technique that creates a perceptual map illustrating of c - store image. Results: The results point out that consumers' perception of a different c - store is different. The trend of c- stores are focusing on the dimensions of the function aspect. The customers also put their attention on the psychological dimension, which, in this case, is customer convenience with a sharp point. Almost all stores are bad on store atmospheric in customer- based. Conclusions: The modern retail store chains need to focus on elements to create a store image positioning and improve the perceptions of the consumers towards the store. Besides, customers not only visit the stores, not due to its convenient location, mass media or shopping experience, but also a strong identity for the store's brand image.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.101-116
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• 2020

This study attempts to derive critical success factors and prioritize activities for implementing the automation of software test. Software testing proceeds in five steps of test plan, test case design, test scripting & test environment setup, test execution & evaluation, and test closure. From the literature, twenty influence factors in the five steps were identified. Focus Group Interviews with ten experts in software testing selected fourteen factors on the basis of importance and feasibility. Some factors were further divided to clarify their meanings and the number of influence factors finally became twenty one. A survey on the influence factors was conducted with 75 IT professionals. An importance-feasibility analysis was applied to the survey responses and classified the influence factors into four groups of essential factors, critical factors, low priority factors, and minimal factors. Essential factors include objectives for test automation, strategies for test automation, test automation training, test automation education, setting up test automation environment, setting up test environment, test automation tool selection. Critical factors include management's continued support, management's continued interest, role of automation engineers, and skills of automation engineers. This result suggests that a lot of efforts should be put into SW test plan for the successful SW test automation and SW automation should proceed in consideration with the priorities and resource consumption.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.181-196
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• 2020

Based on the resource-based perspective, this study seeks to understand the relationship between the organizational slack and innovation, and to demonstrate that there exists a difference in the influence of the organizational slack according to the type of innovation by dividing the types of innovation into exploratory and exploitative innovations. They also want to understand the role that network diversity plays in the relationship between organizational slack and innovation. For this purpose, hypothesis and research models were presented based on resource-based perspectives and empirical analysis was conducted on 171 companies. The analysis confirmed that the impact of organizational slack on exploitative innovation is linear, not non-linear, as expected. In other words, the more resources available, the more productive the enterprise is, and the more resources available to the organization have a positive impact on the innovation. On the other hand, exploratory innovation represented an inverse U-shaped relationship between organizational slack and nonlinearity as expected. The control effect of network diversity was only seen in the relationship between organizational slack and exploratory innovation. Through this study, it provides implications such as the importance of network diversity, which is a relationship between companies, and the difference in the utilization of organizational slack according to the type of innovation.

• The Research Journal of the Costume Culture
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• v.28 no.6
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• pp.830-844
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• 2020

The fourth Industrial Revolution, known as digital transformation, has made MZ generation to be the focus of the new consumer market, brought about the use of technological platforms a new consumption method. Currently, as various types of content collaboration are emerging that specifically targeting at the MZ generation. Content collaboration are considered an integration of content to create new values through co-existence and co-prosperity. This study identified the characteristics of collaboration of fashion brands from 2018 using literature and online news articles, and identified and classified through case studies of it determined movie content, game and virtual characters. By this research, it shown that collaboration with movie contents have increased the collaborative synergy by using the story in global media content. Collaboration with mobile games was generally used by young casual and sportswear brands. These brands which utilized characters from mobile games popular with to attract more teen consumers and strengthen brand awareness by adding values of high-technology and scarcity to the familiar images. In addition, collaboration with virtual characters has expanded value of the collaborative approach on expanding the range of advanced digital technology, from a promotional strategy during the distribution process through to the use of virtual models. As such, collaboration using the various types of content has developed beyond simple integration of identities among various areas, integrated products or brands that as a new value.