Figure 11
The network diagram illustrating relationships among key factors influencing drone adoption in last-mile delivery (L M D). At the bottom of the figure, the legend defines three sets of visual encodings. The first legend, titled “L M D priority group,” explains node colors: red represents “Senders,” pink represents “Regulators,” blue represents “Receivers,” and green represents “Societies.” The second legend, titled “Number of articles,” displays three concentric circle symbols labeled “High,” “Medium,” and “Low,” indicating that node size corresponds to the number of research articles associated with each factor. The third legend, titled “Interlinks,” shows three connecting lines of varying thickness labeled “High,” “Medium,” and “Low,” representing the strength of interconnections between the factors. In the diagram, the largest blue circle labeled “Time” is positioned slightly right of center. Thick gray curved lines radiate outward from this node, connecting it to nearly all other factors in the diagram, suggesting strong interrelationships. To the upper right of “Time,” another blue circle of moderate size is labeled “Reach.” Slightly below and to the right of “Time,” a smaller blue circle is labeled “Item condition.” Both “Reach” and “Item condition” are connected to “Time” with medium gray interlink lines. At the lower left corner, a medium-sized red circle labeled “Capacity” appears, linked closely to “Cost,” “Applicability,” and “Time.” On the right side near the bottom, three smaller green circles labeled “Safety,” “Environment,” and “Privacy” are shown. These three nodes are connected to each other and to other nearby nodes with medium to low interlink lines.Network analysis