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Mixed metal oxide (MMO) is one of the widely utilized ceramic materials in various industries. In order to obtain high performance, the specific surface area of MMO should be controlled. Calcination of layered double hydroxide (LDH) is a versatile way to prepare MMO with homogeneous metal distribution and well-developed porosity. Although researchers found that the specific surface area of LDH-originated MMO was relatively high, it had not been systematically investigated how the surface area is controlled under a certain parameter. In this review, we summarized LDH-originated MMO with various starting composition, calcination temperature, and pore developing agent in terms of specific surface area and porosity. Briefly, it was represented that MMOs with Mg-Al components generally had higher specific surface area than Mg-Fe or Zn-Al components. Calcination temperature in the range 300–600 °C resulted in the high specific surface area, while upper or lower temperature reduced the values. Pore developing agent did not result in dramatic increase in MMO; however, the pore size distribution became narrower in the presence of pore developing agents.
Su-Bin Lee; Eun-Hye Ko; Joo Park; Jae-Min Oh. Mixed Metal Oxide by Calcination of Layered Double Hydroxide: Parameters Affecting Specific Surface Area. Nanomaterials 2021, 11, 1153 .
AMA StyleSu-Bin Lee, Eun-Hye Ko, Joo Park, Jae-Min Oh. Mixed Metal Oxide by Calcination of Layered Double Hydroxide: Parameters Affecting Specific Surface Area. Nanomaterials. 2021; 11 (5):1153.
Chicago/Turabian StyleSu-Bin Lee; Eun-Hye Ko; Joo Park; Jae-Min Oh. 2021. "Mixed Metal Oxide by Calcination of Layered Double Hydroxide: Parameters Affecting Specific Surface Area." Nanomaterials 11, no. 5: 1153.
Chang-Soo Sung; Joo Yeon Park. Correction to: Design of an intelligent video surveillance system for crime prevention: applying deep learning technology. Multimedia Tools and Applications 2021, 1 -1.
AMA StyleChang-Soo Sung, Joo Yeon Park. Correction to: Design of an intelligent video surveillance system for crime prevention: applying deep learning technology. Multimedia Tools and Applications. 2021; ():1-1.
Chicago/Turabian StyleChang-Soo Sung; Joo Yeon Park. 2021. "Correction to: Design of an intelligent video surveillance system for crime prevention: applying deep learning technology." Multimedia Tools and Applications , no. : 1-1.
As the security threat and crime rate have been increased all over the globe, the video surveillance system using closed-circuit television (CCTV) has become an essential tool for many security-related applications and is widely used in many areas as a monitoring system. However, most of the data collected by the video surveillance system is used as evidence of objective data after crime and disaster have occurred. And, often time, video surveillance systems tend to be used in a passive manner due to the high cost and human resources. The video surveillance system should actively respond to detect crime and accidents in advance through real-time monitoring and immediately transmit data in case of an accident. This study proposes developing an intelligent video surveillance system that can actively monitor in real-time without human input. In solving the problems of the existing video surveillance system, deep learning technology will be carried through the data processing model design to visualize data for crime detection after building an artificial intelligence server and video surveillance camera. In addition, this design proposes an intelligent surveillance system to quickly and effectively detect crimes by sending a video image and notification message to the web through real-time processing.
Chang-Soo Sung; Joo Yeon Park. Design of an intelligent video surveillance system for crime prevention: applying deep learning technology. Multimedia Tools and Applications 2021, 1 -13.
AMA StyleChang-Soo Sung, Joo Yeon Park. Design of an intelligent video surveillance system for crime prevention: applying deep learning technology. Multimedia Tools and Applications. 2021; ():1-13.
Chicago/Turabian StyleChang-Soo Sung; Joo Yeon Park. 2021. "Design of an intelligent video surveillance system for crime prevention: applying deep learning technology." Multimedia Tools and Applications , no. : 1-13.
Entrepreneurship and Sustainability Issues is a peer-reviewed journal which publishes original research papers and case studies
Joo Yeon Park; Chang Soo Sung. A business model analysis of blockchain technology-based startup. Entrepreneurship and Sustainability Issues 2020, 7, 3048 -3060.
AMA StyleJoo Yeon Park, Chang Soo Sung. A business model analysis of blockchain technology-based startup. Entrepreneurship and Sustainability Issues. 2020; 7 (4):3048-3060.
Chicago/Turabian StyleJoo Yeon Park; Chang Soo Sung. 2020. "A business model analysis of blockchain technology-based startup." Entrepreneurship and Sustainability Issues 7, no. 4: 3048-3060.
As the fourth industrial revolution has been emerging, there are concerns of labor forces being replaced by technology, recent interest on the work-life balance, and the quality of employment has received attention. This study investigates the role of technology startups on employment and innovative performance. Using empirical data from workplace panel data provided by the Korea Labor Institute, this study reveals that technology startups impact the employment quality and innovative performance by the action of technological innovation. The results highlight the quality of employment as a driver for innovative performance in technology startups. The results of this study will provide practical implications for enhancing technology entrepreneurship.
Dae Soo Choi; Chang Soo Sung; Joo Y. Park. How Does Technology Startups Increase Innovative Performance? The Study of Technology Startups on Innovation Focusing on Employment Change in Korea. Sustainability 2020, 12, 551 .
AMA StyleDae Soo Choi, Chang Soo Sung, Joo Y. Park. How Does Technology Startups Increase Innovative Performance? The Study of Technology Startups on Innovation Focusing on Employment Change in Korea. Sustainability. 2020; 12 (2):551.
Chicago/Turabian StyleDae Soo Choi; Chang Soo Sung; Joo Y. Park. 2020. "How Does Technology Startups Increase Innovative Performance? The Study of Technology Startups on Innovation Focusing on Employment Change in Korea." Sustainability 12, no. 2: 551.
The purpose of this study is to identify the difference in firm performance and employment growth between successful and failed capital procurement through equity-based crowdfunding. We conduct an empirical analysis using entire crowdfunding projects that attempted to raise capital through equity-based crowdfunding in South Korea in 2016. We summarize our findings as follows. Descriptive statistics show that the survival rate, sales growth rate, profitability growth, absolute employment growth, and employment growth rate of companies with successful crowdfunding are higher than those of companies with failed crowdfunding. However, from the difference analysis, we do not find a significant difference in the survival rate, sales growth rate, and profitability growth between companies with crowdfunding success and companies with crowdfunding failure. We find that the absolute employment growth and employment growth rate are significantly higher for companies that succeeded in crowdfunding projects compared to companies that did not. In this study, we find that the characteristics of these firms that are conducting or verifying new projects through equity-based crowdfunding financing are similar to those of prior studies results confirming the short-term effects of entrepreneurial activities or new business activities on economic performance and employment growth. In particular, it is very meaningful to confirm that the direct effect of employment growth is also found in start-up firms that raise capital through equity-based crowdfunding. By investigating the difference in firm performance and employment outcomes according to the results of equity-based crowdfunding investment, this study provides useful insights to investors for their efforts to validate participation in crowdfunding. Also, our study raises important policy implications for regulators in their efforts to resolve unemployment and the lack of capital problem for startups and new businesses.
Hanjun Cho; Joo Yeon Park; Chang Soo Sung; Cho; Park; Sung. The Study on the Difference in Corporate Performance and Employment Outcomes According to the Results of Equity-Based Crowdfunding Investment. Journal of Open Innovation: Technology, Market, and Complexity 2019, 5, 83 .
AMA StyleHanjun Cho, Joo Yeon Park, Chang Soo Sung, Cho, Park, Sung. The Study on the Difference in Corporate Performance and Employment Outcomes According to the Results of Equity-Based Crowdfunding Investment. Journal of Open Innovation: Technology, Market, and Complexity. 2019; 5 (4):83.
Chicago/Turabian StyleHanjun Cho; Joo Yeon Park; Chang Soo Sung; Cho; Park; Sung. 2019. "The Study on the Difference in Corporate Performance and Employment Outcomes According to the Results of Equity-Based Crowdfunding Investment." Journal of Open Innovation: Technology, Market, and Complexity 5, no. 4: 83.
Can individuals’ preference for social hierarchies and inequality affect their intention to pursue entrepreneurship? We surveyed university students in two countries and discovered that the answer may be context‐dependent. Findings suggest that the respondents’ views toward hierarchy and group‐based dominance in society, as indicated by social dominance orientation‐dominance (SDO‐D), is related to their Entrepreneurial Intentions (EI) for starting for‐profit companies. Perceived behavioral control (PBC) mediated the relationship between SDO‐D and EI, implying that higher SDO‐D influences people to think more positively about their own capabilities which in turn leads to higher EIs. These general patterns held in the U.S. sample. However, in South Korea's hierarchical society, respondents’ SDO‐D had little effect on EI as SDO‐D did not significantly affect PBC. Our findings suggest that individuals' SDO is an important and overlooked personality trait that may offer additional insights when added to models of EI.
David Y. Choi; Angélica S. Gutierrez; Jae Hyeung Kang; Joo Yeon Park; Chang-Soo Sung. Entrepreneurs as rulers? Insights from the relationship between social dominance orientation and entrepreneurial intention. Journal of Applied Social Psychology 2018, 48, 692 -707.
AMA StyleDavid Y. Choi, Angélica S. Gutierrez, Jae Hyeung Kang, Joo Yeon Park, Chang-Soo Sung. Entrepreneurs as rulers? Insights from the relationship between social dominance orientation and entrepreneurial intention. Journal of Applied Social Psychology. 2018; 48 (12):692-707.
Chicago/Turabian StyleDavid Y. Choi; Angélica S. Gutierrez; Jae Hyeung Kang; Joo Yeon Park; Chang-Soo Sung. 2018. "Entrepreneurs as rulers? Insights from the relationship between social dominance orientation and entrepreneurial intention." Journal of Applied Social Psychology 48, no. 12: 692-707.
Purpose This study aims to explore Accelerators and their practices in sustaining start-ups within their innovative programs for these companies based on the resource-based perspective. Moreover, with an ever-increasing demand for Accelerators amongst start-up companies, this study also demonstrates the importance of Accelerators, as it pertains to new venture creation. Design/methodology/approach This research uses an exploratory case study approach to examine a comparative view of leading Accelerator companies in the USA and Korea based on resource support. Findings The results of this study show that there are a number of differences between Accelerators of the two countries in terms of the resources they support for early-stage start-ups. The findings also show some similarities. However, in Korea, the Accelerator landscape is limited, where mentorship, resources and investments are not readily accessible, resulting in low success rates for Korean start-up companies. These limitations have had a negative trickle-down effect when providing entrepreneurs with strong access to resources and investors, which highly affects the success rates of early-stage start-ups. Practical implications In terms of the resource-based theory, this study contributes to the growth of early start-ups by emphasizing the role of the accelerator and suggesting the extent and impact that entrepreneurs have access to resources and investors. Originality/value With significant growth in start-ups around the world, the necessity for start-up funding and mentorship has increased drastically. Start-up companies need various types of assets, systems, knowledge and information to achieve their goals. In Accelerators, start-ups receive all the aforementioned resources while also improving their entrepreneurial skills. Start-up companies have many options in seeking investors who support both tangible and intangible resources to boost growth. While there is a wealth of information on traditional funding methods, there are few studies that shed light on the role of Accelerators from the resource-based point of view.
Chul Hyun Uhm; Chang Soo Sung; Joo Yeon Park. Understanding the accelerator from resources-based perspective. Asia Pacific Journal of Innovation and Entrepreneurship 2018, 12, 258 -278.
AMA StyleChul Hyun Uhm, Chang Soo Sung, Joo Yeon Park. Understanding the accelerator from resources-based perspective. Asia Pacific Journal of Innovation and Entrepreneurship. 2018; 12 (3):258-278.
Chicago/Turabian StyleChul Hyun Uhm; Chang Soo Sung; Joo Yeon Park. 2018. "Understanding the accelerator from resources-based perspective." Asia Pacific Journal of Innovation and Entrepreneurship 12, no. 3: 258-278.
The purpose of this study is to verify the effectiveness of the entrepreneurship curriculum and the educational program recognized by students and graduates. This paper has studied the improvement of curriculum and educational programs operated by the Graduate School of Entrepreneurship by using Importance-Performance Analysis (IPA). This study was conducted on students and graduates who attended entrepreneurship graduate schools designated by the Ministry of SMEs and Startups (MSS) in Korea. The results of the questionnaire survey were tested the differences of curriculum courses by paired-sample t test and its improvement was analyzed through Importance-Performance Analysis (IPA). According to the research analysis, there was a difference in the preference of the curriculum and the educational program recognized by graduate students and graduates. The results of this study suggested academic and practical implications. In academic terms, this study classified the subject and educational curriculums of entrepreneurship graduate programs through the analysis of importance-satisfaction. In practical terms, this study suggested implications for the improvement of curriculum and educational programs for the activation of entrepreneurship graduate schools.
Chung-Gyu Byun; Chang Soo Sung; Joo Y. Park; Dae Soo Choi. A Study on the Effectiveness of Entrepreneurship Education Programs in Higher Education Institutions: A Case Study of Korean Graduate Programs. Journal of Open Innovation: Technology, Market, and Complexity 2018, 4, 26 .
AMA StyleChung-Gyu Byun, Chang Soo Sung, Joo Y. Park, Dae Soo Choi. A Study on the Effectiveness of Entrepreneurship Education Programs in Higher Education Institutions: A Case Study of Korean Graduate Programs. Journal of Open Innovation: Technology, Market, and Complexity. 2018; 4 (3):26.
Chicago/Turabian StyleChung-Gyu Byun; Chang Soo Sung; Joo Y. Park; Dae Soo Choi. 2018. "A Study on the Effectiveness of Entrepreneurship Education Programs in Higher Education Institutions: A Case Study of Korean Graduate Programs." Journal of Open Innovation: Technology, Market, and Complexity 4, no. 3: 26.
Universities engage in entrepreneurship education to increase social value creation, through students’ new opportunities recognition. However, there are not enough of empirical researches on whether the current entrepreneurship education can be differentiated from other curriculum to improve the opportunity recognition process. This study argues that it is very important for cognitive abilities to be manifested as behavior when students in university are new opportunities recognition. For this purpose, the relationship between problem solving ability, innovation behavior, and opportunity perception was verified empirically. This study was conducted on 203 students who took entrepreneurship education courses at Korean universities. The results of this study showed that problem solving ability positively influenced innovation behavior and opportunity perception. Innovation behavior was identified as a key parameter that partially mediated the relationship between problem solving ability and innovation behavior. The implication of this study is to prove the relationship between individual ‘s problem - solving ability considering the characteristics of education in Korea and the opportunity through innovative behavior and various learning strategies to help entrepreneurship education to design better courses for the future It has important implications for strategic pedagogy that can enhance behavioral elements in development.
Ji Young Kim; Dae Soo Choi; Chang-Soo Sung; Joo Y. Park. The role of problem solving ability on innovative behavior and opportunity recognition in university students. Journal of Open Innovation: Technology, Market, and Complexity 2018, 4, 4 -13.
AMA StyleJi Young Kim, Dae Soo Choi, Chang-Soo Sung, Joo Y. Park. The role of problem solving ability on innovative behavior and opportunity recognition in university students. Journal of Open Innovation: Technology, Market, and Complexity. 2018; 4 (1):4-13.
Chicago/Turabian StyleJi Young Kim; Dae Soo Choi; Chang-Soo Sung; Joo Y. Park. 2018. "The role of problem solving ability on innovative behavior and opportunity recognition in university students." Journal of Open Innovation: Technology, Market, and Complexity 4, no. 1: 4-13.
Sustainability and entrepreneurship are often regarded as binary concepts that have a tradeoff relationship, meaning that the higher the social and environmental consideration, the lower the private and economic benefits. The purpose of this study is to investigate the effect of individual sustainability orientation on opportunity recognition and sustainable entrepreneurship intention, and examine whether it has a tradeoff relationship with entrepreneurship orientation. The result of this study shows that sustainability orientation has a positive relationship with opportunity recognition and entrepreneurship intention related to sustainability. Analysis of the moderating effects of entrepreneurship orientation reveals the positive effect with sustainability orientation but negative effect with opportunity recognition on sustainable entrepreneurship intention. This study would suggest implications to entrepreneurs on how to balance sustainability and entrepreneurship and promote sustainability entrepreneurship.
Chang Soo Sung; Joo Y. Park. Sustainability Orientation and Entrepreneurship Orientation: Is There a Tradeoff Relationship between Them? Sustainability 2018, 10, 379 .
AMA StyleChang Soo Sung, Joo Y. Park. Sustainability Orientation and Entrepreneurship Orientation: Is There a Tradeoff Relationship between Them? Sustainability. 2018; 10 (2):379.
Chicago/Turabian StyleChang Soo Sung; Joo Y. Park. 2018. "Sustainability Orientation and Entrepreneurship Orientation: Is There a Tradeoff Relationship between Them?" Sustainability 10, no. 2: 379.
People use social media to help them solve problems and enhance performance. Users may engage in diverse social interactions online, increasing their knowledge base through both weak and strong ties. In this study we investigate the impact of social networks on job performance, focusing on knowledge quality and diversity based on social network theory and the knowledge-based view. The empirical analysis reveals that the strength of social network ties is strongly associated with knowledge quality in offline interactions, while social network diversity is associated with knowledge quality in online interactions. Knowledge quality acquired from social network has a significant impact on both creativity and productivity of job performance in the workplace. However, knowledge diversity acquired from diverse social network interactions is strongly associated with creativity, but not with productivity. The results of this study increase our understanding of the knowledge sourcing behaviors of workers.
Joo Yeon Park; Il Im; Chang-Soo Sung. Is social networking a waste of time? The impact of social network and knowledge characteristics on job performance. Knowledge Management Research & Practice 2017, 15, 560 -571.
AMA StyleJoo Yeon Park, Il Im, Chang-Soo Sung. Is social networking a waste of time? The impact of social network and knowledge characteristics on job performance. Knowledge Management Research & Practice. 2017; 15 (4):560-571.
Chicago/Turabian StyleJoo Yeon Park; Il Im; Chang-Soo Sung. 2017. "Is social networking a waste of time? The impact of social network and knowledge characteristics on job performance." Knowledge Management Research & Practice 15, no. 4: 560-571.
Social media platforms are an indispensable part of entrepreneurship practices. They offer entrepreneurs a platform for business growth and brand development. However, little is known about the effect of social media use on identifying entrepreneurial opportunities. Utilizing social cognition theory, this research focuses on how certain factors—prior knowledge, alertness, and social media—may impact two aspects of opportunity: the discovery and the creation of entrepreneurial opportunity. This study focuses on the investigation of the moderating role of social media use on entrepreneurial opportunities. The findings have important practical and academic implications for how social media impacts entrepreneurship and can be used to increase the ability of entrepreneurs to find new opportunities.
Joo Y. Park; Chang Soo Sung; Il Im. Does Social Media Use Influence Entrepreneurial Opportunity? A Review of its Moderating Role. Sustainability 2017, 9, 1593 .
AMA StyleJoo Y. Park, Chang Soo Sung, Il Im. Does Social Media Use Influence Entrepreneurial Opportunity? A Review of its Moderating Role. Sustainability. 2017; 9 (9):1593.
Chicago/Turabian StyleJoo Y. Park; Chang Soo Sung; Il Im. 2017. "Does Social Media Use Influence Entrepreneurial Opportunity? A Review of its Moderating Role." Sustainability 9, no. 9: 1593.
Health information systems use technologies in health care to improve the overall effectiveness of patient care and become important part in health care services. Among other diseases, pressure ulcers, a skin disease arise from prolonged exposure to high pressure points, is required to check patient’s body state and an electronic monitoring system enables to support constant body check with sharing accurate data with professionals. Although technological perspectives have advanced for better prevention of pressure ulcer, only few studies have reported experimental results and clinical responses on the preventive methods in terms of its effectiveness and comfort, and most preventive systems for pressure ulcer risk do not fulfill basic requirements such as sufficient reliability, unobtrusiveness, long-term usage and easy monitoring at various types of equipment. The purpose of this study is to examine a monitoring sensor-based eHealth image system to support pressure ulcer treatment and identify the effectiveness of the system presenting the system architecture. The result of this study would provide support and insight of using the eHealth monitoring system to professionals who need to manage and care of patients.
Chang Soo Sung; Joo Y. Park. A monitoring sensor-based eHealth image system for pressure ulcer prevention. Multimedia Tools and Applications 2017, 78, 5255 -5267.
AMA StyleChang Soo Sung, Joo Y. Park. A monitoring sensor-based eHealth image system for pressure ulcer prevention. Multimedia Tools and Applications. 2017; 78 (5):5255-5267.
Chicago/Turabian StyleChang Soo Sung; Joo Y. Park. 2017. "A monitoring sensor-based eHealth image system for pressure ulcer prevention." Multimedia Tools and Applications 78, no. 5: 5255-5267.
Chang Soo Sung; Dongguk University; Joo Y. Park; Yonsei University. A Study on the Installation of Surveillance System and Safe Residential Environment in the Urban Regeneration. Residential Environment Institute Of Korea 2017, 15, 113 -122.
AMA StyleChang Soo Sung, Dongguk University, Joo Y. Park, Yonsei University. A Study on the Installation of Surveillance System and Safe Residential Environment in the Urban Regeneration. Residential Environment Institute Of Korea. 2017; 15 (4):113-122.
Chicago/Turabian StyleChang Soo Sung; Dongguk University; Joo Y. Park; Yonsei University. 2017. "A Study on the Installation of Surveillance System and Safe Residential Environment in the Urban Regeneration." Residential Environment Institute Of Korea 15, no. 4: 113-122.
Smart devices such as smart phone play an important role in networked environments as connecting to other network devices and Internet Things. Smart phone combines the features of cell phone and a personal computer operating system. And it has become one of vital elements for modern people and society. However, smartphone has drawbacks like spam and security. Globally, people are exposed to spam call that they receive promotion calls from twice to dozens of times a day, spam call and voice phishing due to hacking and personal information leak in the internet environment. This phenomenon can cause personal stress, anxiety due to phone bank fraud, waste of time for receiving spam call, disturbance during work, criminal and the other serious social problems. In the present study, Humming Call system has been studied and developed to provide the measurement for evaluation and activation of service to prevent spam call in advance as a solution for the aforementioned problem. Hamming call is a service which receives information to help call through differentiation from existing service related to anti-spam system from DB (Internal DB) and Server. Then it provides the information for incoming call and outgoing call. To measure the actual performance by utilizing the system of this present study, DB has used CUBRID DBMS for 6 months and data stored in DB have been extracted through SQL Statement. The results indicate that this system prevents such problem for over 30%. If main function among various functions of this system is specialized and developed focusing on management of spam call from phone number, the system would perform more effectively.
Chang Soo Sung; Chi Ha Kim; Joo Yeon Park. Development of humming call system for blocking spam on a smartphone. Multimedia Tools and Applications 2017, 76, 17371 -17383.
AMA StyleChang Soo Sung, Chi Ha Kim, Joo Yeon Park. Development of humming call system for blocking spam on a smartphone. Multimedia Tools and Applications. 2017; 76 (16):17371-17383.
Chicago/Turabian StyleChang Soo Sung; Chi Ha Kim; Joo Yeon Park. 2017. "Development of humming call system for blocking spam on a smartphone." Multimedia Tools and Applications 76, no. 16: 17371-17383.
Joo Yeon Park; Kun Shin Im; Joon S. Kim. The role of IT human capability in the knowledge transfer process in IT outsourcing context. Information & Management 2011, 48, 53 -61.
AMA StyleJoo Yeon Park, Kun Shin Im, Joon S. Kim. The role of IT human capability in the knowledge transfer process in IT outsourcing context. Information & Management. 2011; 48 (1):53-61.
Chicago/Turabian StyleJoo Yeon Park; Kun Shin Im; Joon S. Kim. 2011. "The role of IT human capability in the knowledge transfer process in IT outsourcing context." Information & Management 48, no. 1: 53-61.
The purpose of our work was to examine the effectiveness of information system sourcing from the perspective of service quality and maintenance efforts. We empirically found that there were significant differences in service quality, but not in maintenance efforts, between insourced and outsourced systems. We also found that the level of service quality and maintenance efforts across system sourcing types varied as a system grew older. Our results suggested that outsourcing may not always be the correct choice for reducing costs and increasing efficiency over the long term. This work also considered the effect of issues like productivity gains from a reduced need for system maintenance and the cost savings achieved by choosing sourcing options wisely.
Joo-Yeon Park; Joon S. Kim. The impact of IS sourcing type on service quality and maintenance efforts. Information & Management 2005, 42, 261 -274.
AMA StyleJoo-Yeon Park, Joon S. Kim. The impact of IS sourcing type on service quality and maintenance efforts. Information & Management. 2005; 42 (2):261-274.
Chicago/Turabian StyleJoo-Yeon Park; Joon S. Kim. 2005. "The impact of IS sourcing type on service quality and maintenance efforts." Information & Management 42, no. 2: 261-274.