18 challenges

Good catch. 

The abstract mentions 18 essential challenges, but the abstract itself only lists the top five. To see all 18, you normally need access to the full article or its appendix, where the Fuzzy Delphi Method screened the original 30 challenges down to 18. The abstract does not provide the complete list. (ScienceDirect)

Based on the paper's methodology, the authors:

1. Identified 30 initial Industry 4.0–Circular Economy challenges from literature and expert input.

2. Applied the Fuzzy Delphi Method (FDM) to remove less important factors.

3. Retained 18 essential challenges.

4. Then used Interpretive Structural Modelling (ISM) to determine relationships among them. (ScienceDirect)

The five most influential challenges reported in the abstract are:

1. Lack of automation system virtualization

2. Unclear economic benefit of digital investment

3. Lack of process design

4. Unstable connectivity among firms

5. Employment disruptions (job displacement concerns) (ScienceDirect)

For your DBA

You actually do not need all 18 challenges unless you are specifically reviewing Industry 4.0 barriers.

For your section:

2.1 Technological and Organizational Transformation in Labour-Intensive Industries

you can use the paper to support the argument that palm oil mills face multiple barriers to digital transformation, including:

• Technological barriers (automation and virtualization limitations)

• Financial barriers (unclear return on investment)

• Process barriers (lack of process redesign)

• Inter-organizational barriers (poor connectivity across firms)

• Human resource barriers (employment disruption concerns) (ScienceDirect)

This is actually more useful for your literature review than listing all 18 challenges.

A DBA-style paragraph

You could write:

Abdul-Hamid et al. (2020) identified several barriers to Industry 4.0

One more thing: if you have access through your university library, try downloading the article PDF and send me the appendix or the table containing the challenges. I can then help extract all 18 challenges and group them into organizational, environmental, and individual themes, which would fit very nicely with your conceptual framework.

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