Method and implementation
This chapter aims to explain the research design and the course of action employed to answer the research questions. To increase reliability of the research, it is crucial to define and present the process of research for the scrutiny of the reader. At first, adopted research methods are presented, which is followed by a discussion of data collection techniques. This chapter closes with the illustration of the research process in detail.
The research method is often referred as the general plan about how to answer research questions (Saunders et al., 2012). As it was claimed by Glazier (1992), ”because a satisfactory means of evaluating qualitative research methods has not been found, validity and reliability are often used as the primary means of ensuring integrity”. Furthermore, he suggested that reliability can be guaranteed through the application of triangulation. Therefore, multiple research methods are employed in this thesis to achieve method triangulation, which aims to check the consistency of findings by using different research techniques (Williamson, 2002). Research methods adopted in this study are literature review and case study. In following sections, these methods are further explored and the choice is motivated.
Literature review is a desk-based research strategy which is used to critically describe, review, and interpret what is already known about a topic and add new insights on the topic using secondary sources (Jesson et al., 2011). It is frequently used as a data collection method to develop a theoretical background or framework for further exploration of the research problems (Armitage & Keeble-Ramsay, 2009). As it is claimed by Denney & Tewksbury (2013), scientific knowledge accumulates so rapidly that it is not realistic to expect readers to be familiar with all the relevant background and pre -existing knowledge about any topic. Therefore, a literature review is vital for making a research understandable as it shares with the reader the results of other studies that are closely related to the study being reported (Fraenkel & Wallen, 1990). Meanwhile, a literature review relates a study to the larger, ongoing dialog in the literature about a topic, filling gaps and extending prior studies (Marshall & Rossman, 1989). Within this thesis, the research subject is relatively young, acquainting the reader with basic knowledge about the topic is important for allowing the reader follow the thoughts behind the research process. Therefore, literature review is regarded as a strategic choice of research method instead of being a minor part of the case study in this thesis.
One approach to undertaking a review of existing literature is called systematic literature review, which has been used by increasing number of researchers in the past decade (Creswell, 2009). In contrast to other types of literature review, systematic literature review follows a structured approach: Firstly, a body of potentially relevant publications is identified; Thereafter, each publications is evaluated according to clearly defined criteria for inclusion or exclusion set beforehand (Boell and Cezec-Kecmanovic , 2010). The process is structured so that it is potentially reproducible by other researchers (Greenhalgh, 1997). The aim of systematic literature review is therefore to apply more rigorous methods when searching for existing literature, in order to avoid the waste of time and resources on unnecessary studies (Oxman, 1995).
As it is claimed by Boell and Cezec-Kecmanovic (2010), a systematic literature review offers unbiased, complete and reproducible results that providing an audit trail for the researcher’s decisions and interpretations. However, following this structured process requires the research question that is being investigated to be fixed before the literature review starts. Therefore, a systematic literature review may hinder researchers from pursuing further literature if the process does not match the initially set question (Boell and Cezec-Kecmanovic 2010). As it is criticized by MacLure (2005), “diversions into unanticipated areas are not encouraged… Learning from adjacent areas is not recommended either”. It conflicts with the fact that a deeper understanding of the research problem is gained as the literature review progresses, with the researcher becoming more aware of what questions are most relevant or pressing (Boell and Cezec-Kecmanovic 2010). Besides, it is important that concepts included in the literature review cover the entire (relevant and related) scope of previous literature pertaining to the current research topic, even if it does not directly coincide with it (Denney & Tewksbury, 2013). Under this situation, the usage of pre-defined keywords in systematic approaches may miss relevant publications that could be found by using different wording (Denney & Tewksbury, 2013). Furthermore, systematic literature reviews require a considerable amount of effort that is likely to exceed the scope of a master thesis when applied thoroughly (Armitage & Keeble-Ramsay, 2009). Thus, a systematic literature review is unsuitable for the chosen research topic of the thesis.
As an alternative to systematic literature review, hermeneutic circle takes into account how the understanding of parts relates to the understanding of a larger whole and vice versa (Boell and Cezec-Kecmanovic 2010). Identifying the process of understanding development as open ended and circular in nature, hermeneutic provides a different framework for describing literature review as Figure 10 shows (Boell and Cezec-Kecmanovic 2010). It lies under the precondition that understanding of individual texts should proceed from a thorough reading of relevant texts instead of being an isolated process. In this way, reviewing literature is performed as an iterative process that can be described by moving from the whole relevant literature to particular texts and from there back to the whole body of relevant texts (Boell and Cezec-Kecmanovic 2010). In contrast to systematic literature review, the exact pre -definition of keywords as search term is not required, neither is the identification of all potentially relevant literature at the beginning of the process. Consequently, hermeneutic circle is considered to be more suitable for guiding the literature review process for this thesis.
When selecting keywords for search term, it is inevitable that wider searches will retrieve more documents making a more laborious selection necessary while narrow searches may omit relevant documents (Boell and Cezec-Kecmanovic 2010). Thus, broad search terms were used at the beginning to grasp the whole body of potentially relevant literature in order to develop understand of the research topic. The following search operators were used:
(Industry 4.0 OR The Fourth Industrial Revolution) AND (Cyber-Physical System OR CPS)
Thereafter, the search is narrowed down to the integration between CPS and maintenance activities for a more thorough literature review to answer RQ1. The following search term was used:
(Cyber-physical system OR CPS) AND (Maintenance OR Maintenance management OR Physical Asset Management).
Document types were limited to books, scientific journals and conference proceedings. The search process included databases such as Scopus, Primo, Baidu Scholar and Google Scholar. Sources that were written in Chinese were excluded as well as publications that are accessible through these databases. Thereafter, publications were sorted and omitted according to their relevance, number of citations as well as abstracts and keywords. The thorough reading of remaining literature provides additional potentially relevant texts based on reference tracking. Such a iterative process was repeated several times under the guidance of hermeneutic circle until the theoretical saturation was reached.
According to Yin (2003), case study is an appropriate research method for exploring a contemporary phenomenon within its real-life context. It can be used for description of phenomena, development and testing of theory (Cavaye, 1996). Moreover, it is especially effective when limited information is known about the phenomenon and current perspectives seem to be inadequate (Eisenhardt, 1989). Furthermore, as it is claimed by Dubois & Gadde (1999), case study research method is the best choice when the researcher focuses on understanding the interaction between a phenomenon and its context. In this thesis, the research subject is relatively young and it is crucial to investigate how CPS interacts with the environment within Industry 4.0 concept. For both research problems, the context has profound impacts on the phenomenon and it is almost impossible to answer the problems separately from its surrounding environment, the new production era with the fourth industrial revolution. As for the design of case study, single-case design allows researchers to investigate phenomena in-depth to provide rich description and understanding (Williamson,2002). The single case in this thesis may be used as a pilot and findings may be generalizable to other cases when additional cases test and confirm the findings in other settings (Lee, 1989). In other words, this case study may be used as a reference for future studies and the results are possible to be confirmed by other researchers. The unit of analysis is maintenance process within the production system of the case company. Taking the analysis unit, and observation of key individuals involved in these maintenance activities, into account provide information required for fulfilling the research aim. In following sections, the case company is introduced and reasons for the choice are presented.
Eisenhardt (1989) suggests that the selection of cases involving extreme situations and polar type is meaningful when only a limited number of cases are studied. Therefore, this thesis was conducted in collaboration with Fuyao Group, which is the first company in China to start implementing Industry 4.0 and represents the polar type within the industry. As the biggest automotive glass manufacturing company, Fuyao occupies two-third of the automotive glass market in China. The company owns over 100 factories and warehouses all over the world and its business has been extended to countries including Russia, Australia, U.S.A, Japan etc. Production systems of the case company are highly automated while the main tasks of operators are monitoring and carrying out maintenance activities manually. Being a cross-national company which was formed in 1987, Fuyao is capable of providing a mature and relatively stable production environment to be studied and observed. Moreover, the case company is chosen by the government as the experimental field for implementing Industry 4.0 and results are supposed to be generalized to other companies. Taking these discussions above, and the existence of problems in maintenance activities of the company, into account makes Fuyao a decent choice as the case company. The factory located in the headquarters of Fuyao Group was chosen as the target to conduct the study.
Choice of methodological instruments Interview
An interview is a purposeful conversation between at least two people in which the interviewer propose questions and the interviewee listens and responds (Saunders et al., 2012). According to Williamson (2002), exploratory interviews can be very useful in the early stages of most research projects. It is usually considered as a highly productive method of data collection, since the interviewer has the opportunity to pursue specific issues of concern as they emerge (Bryman & Bell, 2011). Moreover, given that personal contact is mandatory between the interviewer and interviewee, interviews are often easier to obtain a higher response rate than other research techniques (Williamson, 2002).
According to Williamson (2002), interviews can be categorized as structured, unstructured and semi-structured. Within this study, unstructured interviews were conducted with the production manager firstly to develop an overall understanding of the structure of the case company. Furthermore, as it was suggested by the manager, key individuals were identified as potential participants for later studies. Thereafter, semi-structured interviews were used to collect in-depth knowledge concerns the targeted research topic while participants have the possibility to provide additional information in the meantime. These two types of interviews allows interviewees to explain, or build on their responds, which is crucial to grasp participants’ perceptions (Bryman & Bell, 2011). In the research process section, more details about these interviews will be explained and illustrated.
A focus group is “ a carefully planned discussion designed to obtain perceptions on a defined area of interest in a permissive, non -threatening environment…conducted with approximately 7 to 10 people by a skilled interviewer” (Krueger, 1994). It is a data collection techniques typically used in a case study research (Williamson, 2002).
The working process and environment of the case company was complex and the researchers had no related knowledge regarding the production of automotive glass. Therefore, the research process of the case study comprises orientation study, which aims to develop an understanding of the factory and identify key individuals/phenomenon for further investigations, and the main study.
This phase of research process started with a Gemba walk along the whole production line while being accompanied by the production manager. The complete production processes were observed by the researchers along with the brief introduction presented by the manager. Thereafter, two semi-structured were conducted with the production manager and the vice manager separately. Both interviews were conducted in their office and lasted for approximately one hour and most questions were relatively general. Furthermore, as one of the questions included in the interviews, a list of key individuals who work directly with maintenance process was suggested by both managers. At the beginning of the interviews, both managers claimed that they were reluctant to be recorded. Therefore, in order not to interrupt the interviews, one of us was proposing questions while the other one was taking notes of what the interviewee said. There interviews laid a solid foundation for later main study since potential participant were identified and the information regarding when they were available was offered by the manager.
The main study was conducted three days after the orientation study due to the consumption of time on sorting out notes from previous interviews and contacting the interviewees for the following study. Along with the support from the production manager, the fact that all interviewees being co-operative made it relatively easy to schedule all the interviews. Moreover, all interviewees were informed that their answers would only be used for the study without being exposed to other colleagues including their managers. As recording these interviews was not a possible option, field notes were taken during interviews and summarized shortly afterwards.
Semi-structured interviews were conducted with the maintenance manager, two maintenance engineers and four maintenance operators. The maintenance manager, who was in charge of the maintenance department, was interviewed first since he was more likely to be capable of providing sufficient information regarding the overall maintenance environment of the factory. Thereafter, two engineers and four operators were interviewed with varied questions since they were responsible for performing different maintenance activities. All interviews were conducted individually in the meeting room according to the guideline designed in advance along with slight changes in sub-questions depending on the flow of the interview. Interviewees were encouraged to propose examples from their work experience in accordance with their answers. The overall information of these interviews were illustrated in Table 5.
Two one-hour focus groups are conducted in the case study. The authors acted as moderators. One group contains 8 maintenance operators working in the selected production line (Group A). These 8 operators come from two different working teams in order to validate the final results. The other group consists of 6 maintenance engineers who comes from three different production line (Group B). The reason to conduct two focus groups is that the maintenance operators and maintenance engineers have different tasks during the maintenance process. Maintenance tasks exception should be done by the maintenance operators while planning, scheduling, control and supervision should be conducted by the maintenance engineers. Group A was asked to give an account what restricts and drives them to complete their tasks effectively and efficiently while Group B was asked to give an account what restricts and drives them to make decisions effectively and efficiently. The results of these two focus groups were concluded in a simple force field analysis based on Lewin (1951) for both of two focus groups.
In this chapter, the researchers provided information that enables the reader to evaluate the adequacy of the research process and its outcomes. Furthermore, it is possible for the reader to repeat the research process and evaluate the validity and reliability of the study. At first, the adopted research methods in the thesis were presented. Thereafter, the choice of data collection techniques were motivated and the case company was explored. Lastly, details of the research process were revealed.
1.2 PROBLEM DESCRIPTION
1.3 PURPOSE AND RESEARCH QUESTIONS
2 Theoretical background
2.1 INDUSTRY 4.0-THE FOURTH INDUSTRIAL REVOLUTION
2.2 CYBER-PHYSICAL SYSTEM
2.3 THE ADOPTION OF CPS IN THE FACTORY
2.4 OUTCOMES OF THE APPLICATION OF CPS
3 Method and implementation
3.1 RESEARCH METHOD
3.2 RESEARCH PROCESS
4 Findings and analysis
4.1 THEORETICAL FINDINGS
4.2 EMPIRICAL FINDINGS
5 Discussion and conclusions
5.1 ANSWERING RESEARCH QUESTION 1
5.2 ANSWERING RESEARCH QUESTION 2
5.3 DISCUSSION OF METHOD
5.4 DISCUSSION OF FINDINGS
GET THE COMPLETE PROJECT
Cyber-Physical System for maintenance in industry 4.0