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SUPPLY CHAIN RESILIENCE:
How supply chain robustness enhances supply chain resilience
22nd of June 2015 Elbrich de Jong Student number: 1932101 Snikkevaardersgang 7a 9711RW Groningen Tel: +31 (0)622730240 elbrichdejong@gmail.com
Master thesis MSc. Supply Chain Management
First supervisor: dr. K. Scholten
Second supervisor: prof. dr. D. P. van Donk
University of Groningen, Faculty of Economics and Business
P.O. Box 800, 9700 AZ Groningen
Acknowledgements
2 CONTENTS 1. INTRODUCTION ... 5 2. THEORY ... 6 2.1 Resilience... 6 2.2 Robustness ... 7 Proactive planning ... 10 Maintain functionality ... 11 2.3 Conceptual model ... 12 3. METHODOLOGY ... 13
3.1 Case setting and selection ... 13
3.2 Data collection ... 16
3.3 Data analyses ... 18
4. FINDINGS ... 20
4.1 The importance of visibility ... 21
The importance of visibility in the proactive planning phase ... 21
The importance of visibility in the phase of maintaining functionality ... 23
4.2 Picking appropriate redundancy ... 24
4.3 Flexibility... 26
4.4 Accountability and ownership ... 27
5. DISCUSSION ... 28
6. CONCLUSION ... 33
6.1 Managerial implications ... 33
6.2 Limitations and suggestions for further research ... 34
7. REFERENCES ... 36
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Appendix A: Case selection matrix ... 39
Appendix B: Case study protocol ... 40
Appendix C: Within-case analysis ... 43
Case 1 Fire ... 43
Case 2 Peak in milk supply ... 45
Case 3 Capacity delay ... 48
Case 4 Quota abolishment ... 50
Appendix D: Cross-case analysis ... 55
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ABSTRACT
Purpose – This thesis aims to answer the research question how supply chain robustness
enhances supply chain resilience. Supply chain robustness is present in proactive planning and the phase of maintaining functionality. The formative elements are visibility, redundancy and flexibility. The purpose is to identify underlying mechanisms explaining how proactive planning enhances the ability to maintain functionality.
Design / Methodology / Approach – An explorative multiple case study is conducted at a
large dairy producer who overlooks the whole supply chain. Data is gathered through interviews, observations in meetings and by studying archival sources. All cases are analyzed following a multi-step coding procedure to discover patterns on how supply chain robustness enhances supply chain resilience.
Findings – The empirical data shows that proactive planning enhances the ability to maintain
functionality mainly by increasing the velocity and flexibility of the response, or even prevent a disruption. Velocity is enhanced by considering scenario management, share these scenarios with relevant stakeholders and choose appropriate and most profitable mitigation measures in the proactive planning phase. Accountability and ownership are new factors found, which also enhance the velocity and flexibility of response to a disruption.
Practical implications – The research provides insights in what aspects to consider in the
proactive planning phase. Such as the creating high data availability and accuracy for scenario planning, combine redundant resources with flexibility and create accountability by making people problem owners.
Originality / value – Literature does point out that supply chain robustness enhances supply
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1. INTRODUCTION
Prevention is better than cure. In an ideal world every disruptions can be prevented from happening to secure business continuity. However, not all disruptions can be avoided. Every form of business activity has an inherent risk of unexpected disturbances to occur that have financial consequences or even lead to bankruptcy (Skipper & Hanna, 2009). Therefore, it is important that a supply chain considers resilience in order to effectively deal with disruptions: “the adaptive capability of the supply chain to prepare for unexpected events, respond to disruptions, and recover from them by maintaining continuity of operations at the desired level of connectedness and control over structure and function”(Ponomorov & Holcomb, 2009, p. 131). Many authors tried to conceptualize resilience (Blackhurst, Craighead, Elkins, & Handfield, 2005; Jüttner & Maklan, 2011; Pettit, Croxton, & Fiksel, 2013). This article follows the view of Wieland & Wallenburg (2013), who that state supply chain resilience consists of a proactive and a reactive aspect, respectively called robustness and agility (Wieland & Wallenburg, 2012). Supply chain robustness encompasses how a supply chain can proactively prepare, so that an event does not become a disruption and the supply chain can thus maintain functionality. While there has been a lot of research on the reactive part of resilience, supply chain agility, less is known in literature on the proactive part; supply chain robustness.
Ponomarov & Holcomb (2009) highlight another gap in literature; the failure to conceptualize the complexity of cause-effect relationships between some related constructs, such as the effect of supply chain robustness on supply chain resilience. Additionally, there is no clear understanding of the dimensions, antecedents and moderators of supply chain robustness (Durach, Wieland, & Machuca, 2015). Previous research focuses on how to measure robustness (Nair & Vidal, 2011; Tang, 2006) and identifies broad antecedents of robustness (Durach et al., 2015). What has not yet received attention in literature is how exactly supply chain robustness is created and how it relates to supply chain resilience. Therefore this research aims to answer the question: How can supply chain robustness enhance supply chain resilience when experiencing disruptions?
6 supply chain resilience and robustness relate. In doing so it will become clear what underlying mechanisms of robustness enhances resilience. Lastly it contributes to managers by giving them insights in how their supply chains can become more resilient via supply chain robustness. This is relevant because the level of resilience determines the impact of disruptions on an organization (Blackhurst, Dunn, & Craighead, 2011).
The remainder of the paper is organized as follows. A literature review gives the theoretical background of supply chain resilience and robustness. The methodology describes and argues for the executed case study. The findings section presents the results and these will be related to literature in the discussion, finally presenting the end model. Lastly a conclusion is given, with limitations to the research and suggestions for further research.
2. THEORY
2.1 ResilienceThe concept of supply chain resilience has been defined by many authors (Blackhurst et al., 2011; Johnson, Elliott, & Drake, 2013; Pettit, Croxton, & Fiksel, 2013; Wieland & Wallenburg, 2013) and this article uses the definition of Ponomorov & Holcomb (2006) that is stated in the introduction. This definition is most complete since it covers both the ability of a supply chain to prepare for an (unexpected) disruption, to maintain functionality and even possibly being able to find a new equilibrium after a disturbance. It is important to note that a resilient supply chain can deal with both foreseeable and unforeseeable disruptions and events (Pettit, Fiksel, & Croxton, 2010; Scholten, Sharkey Scott, & Fynes, 2014).
7 term impact. All significant disruptions have this typical profile in terms of effect of the disruption on company performance (Sheffi & Rice, 2005). In the phases of Sheffi & Rice (2005) robustness (proactive) is present in the preparation phase and in the phase of the first response to a disruption. Agility (reactive) is present in the phase of the first response and all following phases.
This article will focus on the robustness aspect of resilience because if an organization is ultimately prepared in the preparation phase, it does not even have to go through the other phases in extend; the supply chain can maintain functionality (Hohenstein et al., 2015). An example of a robust measure is that enough capacity is available in the form of inventory to absorb the shock of a disruption and a respond in the reactive form is not even needed (Tang, 2006). Preparing in the readiness phase thus means fostering robustness measures to absorb sudden shocks and reduce potential disruption impact on performance (Hohenstein et al., 2015).
Figure 1 Disruption phases (Sheffi & Rice, 2005) 2.2 Robustness
8 Haijema, & van der Vorst, 2013). The underlying constructs that create supply chain robustness differ among the studies. In table 1 an overview is created of the most prevalent definitions.
The definition of Klibi et al. (2009) highlights the proactive planning aspect of supply chain robustness. Proactive planning is reflected by avoidance of risk and anticipation respectively named by Wieland & Wallenburg (2013) and Durach et al. (2013). Supply chain robustness is not solely about proactive planning since the definitions of Meepetchdee et al. (2007) and Brandon-Jones et al. (2014) emphasize the ability of a supply chain to maintain functionality since a robust supply chain endures rather than responds to changes (Husdal, 2010). Maintaining functionality is according to Wieland & Wallenburg (2013) "Resistance to forecasted change", this implies that supply chain robustness can merely deal with forecasted change. However, this article follows the view that supply chain robustness can deal with both foreseeable and unforeseeable disruptions (Rice & Caniato, 2003).
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Robustness
Proactive planning Maintain functionality
Wieland & Wallenburg (2012, p.304)
Anticipation: "Forecast of possible future changes"
Preparedness: "Resistance to forecasted change" Durach et al.
(2015, p. 123)
Avoidance (prevent): "Ability of a supply chain not to be affected by
the change"
Resistance (hedge): "Ability of a supply chain to withstand
change"
Meepetchdee, Shah (2007, p. 203)
"The extent to which the supply chain is able to carry out its functions despite some damage done to it [such as the
removal of some of the components in the logistical
network]" Brandon-jones, Squire, Autry, Petersen (2014 p. 58)
"The ability of the supply chain to maintain its function
despite internal or external disruptions"
Klibi et al. (2010, p.290)
"A [supply chain network] design is robust, for the planning horizon considered, if it is capable of providing sustainable value creation under all plausible
future scenarios"
Wieland and Wallenburg (2012, p. 890)
"Robustness is a proactive strategy that can be defined as the ability of a supply chain to resist change without adapting its
initial stable configuration"
Taking a closer look at multiple articles, that form the base of this study, results show some overlap in the instruments given in each article on how to be robust. To provide a clear overview this article constructed table 2 which shows the array of instruments of supply chain robustness so far described in literature. The instruments shown in table 2 are defined at a very practical level. Therefore, these instruments are grouped into several types and the types were abstracted into three categories; redundancy, flexibility and visibility. These three formative elements of supply chain robustness will be explained in greater detail below in relation to the two phases of supply chain robustness.
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Categories
Redundancy Flexibility Visibility
Type of instrument Buffering (inventory management) Sourcing Product design Logistics Visibility
Nair, Vidal (2011) Inventory levels, total costs and backorders
Tang (2006) Strategic stock, Economic supply incentives, Revenue management Flexible supply base, Make-and-buy Silent product rollover, Dynamic assortment planning Flexible transport Postponement Wieland, Wallenburg (2013) Inventory Multiple sources of supply, Make and buy
Product design Logistical network design Hohenstein, Feisel, Hartmann, Giunipero (2015) Production slack, transportation capacities Multiple sourcing Early warning indicators, information sharing, real-time and financial monitoring Table 2 Factors of supply chain robustness
Proactive planning
11 (Hohenstein et al., 2015). Tang (2006) argues that a robust supply chain strategy is useless unless a firm can execute the strategy in a proactive manner.
A concept which can increase the success of proactive planning is visibility which literally means seeing from one end of the pipeline to the other (Christopher & Peck, 2004). In the readiness phase visibility is one of the most important proactive aspects (Hohenstein et al., 2015) and in the reactive phase visibility is said to be a prerequisite for responding to changes (Wieland & Wallenburg, 2013). We define visibility in line with Francis (2008, p. 182) as “the identity, location and status of entities transiting the supply chain, captured in timely messages about events, along with the planned and actual dates/times of these events”. The sub elements of visibility are early warning indicators and real-time/financial monitoring (Hohenstein et al., 2015) and therewith visibility will prevent unnecessary interventions, ineffective decisions and overreaction when a disruption takes place (Christopher & Lee, 2004). Visibility is meant to guard the environment and make the organization aware of potential turbulence. Proactive planning gives a better understanding of risk which is important to develop appropriate countermeasure such as flexibility and redundancy (Zsidisin & Wagner, 2010) and visibility is of critical importance to do so (Scholten et al., 2014). Redundancy and flexibility are considered a core element in each phase of supply chain resilience, thus in both the proactive and reactive phase (Hohenstein et al., 2015).
Maintain functionality
From table 1 it is observed that all definitions of robustness focus on the ability to maintain functionality (Brandon-jones, Squire, Autry, & Petersen, 2014) while not all definitions include the proactive planning aspect. This indicates that maintaining functionality is the main element of supply chain robustness. However, proactive planning is very useful since it gives a supply chain insights into what measures need to be taken to maintain functionality (Saenz & Revilla, 2014). As already noted in the previous part, proactive planning allows an organization to pick more appropriate measures to maintain functionality, like redundancy and flexibility.
12 (Sheffi & Rice, 2005). Redundant resources create buffers and if those buffers are sufficient to absorb the disruption, no response is even needed. Redundancy is often resembled by multiple suppliers and slack resources, allowing the supply chain to respond quickly to sudden changes (Hohenstein et al., 2015) thereby by enhancing velocity. Velocity relates to the speed with which a supply chain can react to market changes/events (Jüttner & Maklan, 2011) and is one of the core elements of supply chain resilience.
Redundancy is thus the most cited category in order to deal with disruptions when considering supply chain robustness, but flexibility is the most referred to element of supply chain resilience (Hohenstein et al., 2015). Supply chain robustness is frequently misunderstood to be a static concept (Brandon-jones et al., 2014) while to maintain functionality robust systems often require flexibility at a component or structural level (Kitano, 2004). Redundancy can be regarded as a route to flexibility (Jüttner & Maklan, 2011; Rice & Caniato, 2003) by creating capacity so that operations can continue following a disruption. Flexibility facilitates coordination processes and enables organizations to cope with uncertainty (Manuj & Mentzer, 2008). Flexibility can be present in sourcing or other areas like order fulfillment, allowing the supply chain to respond effectively by absorbing the risk event (Jüttner & Maklan, 2011). The definition is “the ease with which a supply chain can change its range numbers (i.e. the number of possible ‘options’) and range heterogeneity (i.e. the degree of difference between the ‘options’) in order to cope with a range of market changes/events while performing comparably well” (Jüttner & Maklan, 2011, p. 251). Flexibility, just like redundancy, creates velocity in maintaining functionality (Christopher, 2005); velocity accelerates the speed of reaction and therewith the speed of responsiveness (Christopher & Peck, 2004; Wieland & Wallenburg, 2013).
2.3 Conceptual model
13 Flexibility Redundancy Proactive planning Visbility Maintaining functionality Supply chain robustness Supply chain resilience
Figure 2 Conceptual model
3. METHODOLOGY
To investigate the construct robustness in the context of supply chain resilience an exploratory case study research is adopted, to provide more in-depth insights into the relation of supply chain robustness and supply chain resilience. The unit of analyses is defined as an event; a comprehensive unit of analyses since it represents both a disruption and a near miss. Since robustness is a complex exploratory phenomenon, a case study research is best suitable (Yin, 2009) because it allows questions of why and how to be answered (Voss, Tsikriktsis, & Frohlich, 2002; Yin, 2009). Studying events of a robust supply chain in real-life context allows to discover how, by which underlying mechanisms, robustness enhances supply chain resilience. How the complete case study is carried out, is discussed below and depicted in figure 3.
3.1 Case setting and selection
14 high data availability because all parties active in the supply chain serve the same interests,
Case selection (4 cases)
· Case matrix
· Discussion with manager in organization plus expert in the supply chain field
Data gathering
· Interviews tape recorded and transcribed
· Observation at meetings
· Archival information
Qualitative data analysis
· First order coding
· Second order coding
· With-in case analysis and cross-case analysis
Verify findings
· Discussions manager in organization plus expert in the supply chain field
Existing literature
Figure 3 Research method
15 through all phases of a disruption from proactive planning to the recovery and long term impact.
This study uses a purposive sampling strategy (Patton, 1990). Multiple cases will be studied because this augments external validity and helps to guard against the observers bias (Voss, 2009). Four meaningful cases were selected spanning different kind of events to increase the possibility of generalizing results (Voss, 2009). Preselection was done by compiling a matrix which resulted in 12 optional scenarios (appendix A). Cases were selected based on the possibility for proactive planning and how well functionality was maintained because, as set out in the theoretical background, proactive planning is considered to have an influence on supply chain robustness. According the categories the company uses, the planning horizon can be short (13 weeks), medium (18 months) and long (10 years). Maintaining functionality was measured by looking at the deviation in kilograms of milk as a result of the event, and the time it took to recover. This will be further explained in the following paragraph. Milk is the core product of the dairy producer and therefore the common denominator in all cases; it can be that extra milk needs to be processed or less kilograms of milk could be processed. The supply chain of this organization is mainly supply driven and therefore, the robustness is measured by being able to process all supplies. This is also the reason that only supply and capacity related events were selected, and no demand related events. Cases range on a continuum on proactive planning. By extensive discussions with the manager a selection of four cases was made, which led to theoretical saturation because after the research of the four cases certain phenomena observed were seen before (Eisenhardt, 1989). Table 3 shows the final selection of all cases and their characteristics.
Case 1 Case 2 Case 3 Case 4
A fire put plant down A peak in milk supply Capacity delay Quota abolishment
Planning horizon None 0 days Short 7 days Medium 4 months Long 5 years Maintaining functionality High
(Medium intensity but fast recovery)
High
(High intensity but fast recovery)
Medium
(High intensity and relatively long recovery)
Medium
(High intensity but medium fast recovery)
Case characteristics
· Capacity event · Unique event · Lack of redundancy
made recovery take longer · Flexibility in redundancy and product-mix · Visibility in size of disruption · Supply event · Recurring event · Redundancy caused
this event to not become a disruption · Flexibility in
redundancy and product-mix
· Visibility in redundant capacity and forecasts
· Capacity event · Recurring event · Redundancy caused
this event to not become a disruption · Flexibility in redundancy · Visibility in capacity delay, length · Supply event · Unique event · Redundancy was
created to deal with this event · Flexibility in redundancy and product-mix · Visibility in redundant capacity
16 In table 3 the level of functionality maintained is shown of each case. This was determined by considering the size of the impact, graph 1, together with the affect the disruption had on firm performance. In consultation with the manager of the department it was decided what the affect on firm performance had been in each case and the relative difference between cases. Graph 1 shows how all four cases relate in terms of size of the disruption. The y-axis shows how much deviation in milk is a result of the event and the x-axis shows how long it took for the disruption to be resolved. It is visible that case 2 and 4 are more intense events (the dotted line in case 4 shows the expectations from that point on because the disruption was still occurring at the time of research) but do not last as long and case 1 and 3 are events that are lasting longer but with a less high impact in terms of deviation in kilograms of milk. This can be related to the fact that the disruptions either occur in milk supply or capacity loss.
Graph 1 Size of the impact of each case
3.2 Data collection
To achieve internal triangulation (Voss et al., 2002), data collection involved several sources of data. First, 13 interviews were held among 7 employees inside and outside of the case context department with different points of view on the cases, contributing to the richness and variety of the data (Yin, 2009). Second, observation were done during 9 meetings and the last data source was the study of archival sources. A case study protocol was made (appendix B) to increase consistency of the procedure in each case enhancing the reliability of the research (Yin, 2009). An overview is given in table 4 of data collection per case.
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
Deviation in kilograms of milk
Time after disruption (weeks)
Size of the impact of each case
Peak (deviation compared to forecast 1 month before) Quota abolishment (deviation compared to forecast 1 month before)
Expectations of Quota
Fire
17 An initial interview protocol was prepared based on the literature and discussions with an expert in the field of supply chain resilience and the manager of the department (see appendix B). During the interviews, questions of the protocol probed the informants for answers about how the supply chain normally operates, what kind of proactive planning is done, what was done immediately after the disruption and on longer term after the disruption. Finally evaluating questions were asked that encouraged informants to discuss critical success factors and points for improvement. 13 semi-structured interviews were held and all interviews took place face-to-face in the office buildings of the organization in the spring of 2015, lasted from 30 minutes to an hour and were tape recorded, transcribed verbatim and checked afterwards by the interviewee.
Additionally, the research attended mainly crisis meetings and meetings in which proactive plans were communicated throughout the supply chain. Crisis meetings were attended in which an action plan was made on the spot to mitigate the impact of the disruption. All relevant stakeholders were present, like all business unit managers, logistic manager and planners from the department of this research. Other meetings that were attended concerned the communication of the plans on the short term planning horizon and medium term planning horizon meetings, with almost the same stakeholders as in the crisis meeting. Plans, threats and opportunities were discussed for the coming 13 weeks or 18 months. Lastly, observations were made in the department meetings were the future trends were discussed and multiple scenarios were made. A strategy was made before hand to extract the desired information from these meetings (appendix B). Information was gathered about how the organization proactively plans and communicate these plans, and how the organization acts in times of crisis. Specific attention was paid to discovering patterns in (sequential) procedures when a disruption took place and how the process of proactively planning evolved. At least two meetings were attended so a comparison could be made and consistency in procedures can be checked.
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Table 4 Data collection overview per case
3.3 Data analyses
The qualitative analysis has been conducted by using the software Atlas.ti. First order codes were applied to reduce the data (Miles & Huberman, 1994). A priori codes were made for the general themes according to the theoretical background. The themes were proactive planning, redundancy, flexibility and visibility. To give more detail to those themes, inductive coding led to 19 second order categories. Inductive codes were devised when a new possible aspect of that third order theme came forward. In the third order theme called proactive
Data source Description Length Case
1 2 3 4
Interviews
Internal (of department)
(1) Manager short term planning 90 min. X X X
(2) Manager medium term planning 43 min. X X
(3) Manager milk supply forecast 65 min. X X
(4) Supply chain director 85 min. X X
(5) Manager department 50 min. X X
External (of department)
(6) Manager sales and operation planning of business unit 45 min. X X (7) Director plan & deliver of business unit 47 min. X
Observations during meetings
Short term meeting 1; allocation of the milk to plants 60 min. X X X Short term meeting 2; allocation of the milk to plants 60 min. X X X Medium term meeting 1; allocation of milk to best valorizing
business units 60 min. X X X
Medium term meeting 2; allocation of milk to best valorizing
business units 60 min. X X X
Crisis meeting 1; making a plan to process all milk 45 min. X Crisis meeting 2; making a plan to process all milk 45 min. X Dairy supply chain meeting; discussing future opportunities and
threats 50 min. X X
Documents
Short term planning; slides on plans for allocation of milk to plants
30
slides X X
Short term planning; slides on plans for allocation of milk to plants
30
slides X X Medium term planning; slides on allocating milk to business
units
30
slides X X Medium term planning; slides on allocating milk to business
units
30
slides X X Email traffic in crisis between interviewee (3) and all relevant
stakeholders 6 A4 X
Milk calamity documentation files; showing status of crisis 4 A4 X
Files on strategy for coming 10 years
60
19 planning, special attention was paid to plans changing last minute to see how the organization was flexible in dealing with changes in decisions made on previous plans. With the inductive coding an open mind was kept to possibly identifying factors that contribute to a new aspect of supply chain robustness. Some of the 19 second order categories did indeed not fit into one of the four third order themes, therefore a fifth third order theme emerged; accountability and ownership. Following this inductive coding was the comparison of cases inside these categories to see different dimensions in these categories. An excerpt of the coding tree is shown in table 5. To increase the reliability of the data, findings from interviews and observations were first discussed with personnel of the department to check whether Secondly, in the qualitative data analysis a within-case analysis was made which is visible in appendix C, followed by a cross-case analyses (Miles & Huberman, 1994) of which an excerpt is visible in table 9 in appendix D. For the within case analysis first a case narrative of 1,5 page was made to describe all that happened in the case followed by what actions were taken on all of the third order themes and how it contributed to supply chain resilience. Subsequently the cross case analysis was done to extract patterns from the data. Comparing cases across the proactive planning aspect and how well they maintained functionality helped establish the connection between the theoretical themes and supply chain resilience. Also at this stage the results were shown to personnel of the department to verify the findings.
It should be noted that the data analyses and collection started simultaneously. The final stage of Miles & Huberman (1994) is drawing the conclusions which will be extensively discussed in the following section.
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Table 5 Coding tree (excerpt)
4. FINDINGS
The research provided valuable insights into how supply chain robustness enhances supply chain resilience. Table 6 shows in short the relative findings per case, in table 9 in appendix D a more detailed version can be found. In the following paragraphs further explanation will be given on the causal relationships between factors, with the use of cross case analysis. The first
Data Reduction (First Order Codes) Descriptive Code (Second
Order Categories)
Link to Robustness (Third
Order Theme) “They [plans made beforehand] are essential because it is indeed your risk assessment
and scenario management, that is what makes the execution fairly robust, that you seldom have to go to the crisis mode” (2.3)
Usefulness of proactive planning
Proactive planning “So now they [the project team of build of new capacity] will reduce their ambition and
therewith make plans more realistic, so they lowered their base plan, making additional volume an ambition and not a base plan” (3.2)
Change in plans “We have yearly member surveys where we ask from members what they think they will
supply in milk to us in the coming years” (4.4) Long term planning “If you are short before your plans become reality, you need a feasible plan and ambition
does not make sense” (2.5) Short term planning “The capacity is of course used as much as possible. In the allocation plan is stated on
which locations is still free capacity left” (2.1) Spare capacity
Redundancy “We did outsourcing a lot, we partly outsourced some volumes and we sold a lot more
milk than we used to” (4.2) Sourcing “We do look at producing on stock, in factory X and Y they are now trying to do that but
milk is perishable so it stays difficult” (2.1) Inventory “Always more is possible, but do not ask for them to do it two months. And that is, I
think, a part of flexibility, so you change the product-mix in a factory through which you get more milk absorption, you switch production plans etcetera” (4.5)
Product-mix
Flexibility “In general I have to say that the personnel at production is very flexible” (2.3) Personnel
“Flexibility in the total network, that we are able to produce cheese really fast on a few
locations or even process goat milk” (1.6) Production line “We were not able to take it into account in the plan 1 or 2 days after the fire because the
hub didn't have any clarity on how huge the impact was” (1.2) Data availability
Visibility “The contact you have at cooperative affairs makes acting quick possible, they are much
closer to the operation” (2.1) Decentralisation “They make their own planning, which I would say is a little bit ambitious and therefore
we ask them for a more realistic scenario and that is where we base our decisions on.” (3.2)
Data accuracy
“We have a lot of communication with the project team and the plant, communication is very open, I think that is also an important one, people are not hiding from that” (3.4)
Communication across supply chain
Awareness & Accountability “That you assign a project team and give them the freedom to operate freely and make it
operate autonomous, is one of the reasons that be dealt quick with this disruption” (1.6) Autonomy “When it is crisis people have to act differently and that may cost something and that
sense of urgency is really important” (3.4) Sense of urgency “The problem owning is important, milk logistics is the first, if they can't solve it, it goes
to our allocation planner, if he can't solve it goes to the supply chain manager etcetera” (2.3)
Problem ownership “Another thing that was very good was the solidarity, in times of crisis people are more
focused to one and the same goal” (3.4) Awareness “Good planning and acting on those plans, but most of all the full dedication of the
21 part focusses on the importance of visibility, the second part paragraph focusses on redundancy and the third part focusses on flexibility. Each part will show how the factor contributed in the proactive planning phase and how it enabled maintaining functionality.
Proactive planning Visibility Use of redundancy Use of flexibility Maintained functionality Case 1; Fire in plant --> sudden capacity loss In general planned for unexpected disturbances
High High High High
Case 2; Peak in milk supply --> seasonal increase in supply
Specifically planned for this
disruption
High High Medium High
Case 3; Capacity delay --> gradual loss in capacity
Specifically planned for this
disruption
Medium High Medium Medium
Case 4; Quota abolishment --> more uncertainty and increase in supply Specifically planned for this
disruption
Medium High High Medium
Table 6 Short summary of relative findings
4.1 The importance of visibility
The importance of visibility in the proactive planning phase
Part of the research focused on what the influence was of the length of the planning horizon on the ability to be robust as a supply chain. However, it turned out that the more time an organization has to plan for an event, does not necessarily mean that functionality is better maintained. For example case 4, the quota abolishment, had the longest planning horizon but scored on the level of maintain functionality only medium. On the other side of the spectrum is case 2 where the planning horizon was short to none but functionality was highly maintained. It was observed in the case study that data availability and accuracy are at the basis of making the right choices and this was high in case 2 and lower in case 4.
22 functionality was maintained so well is because forecasting supply was relatively easy at that time because there were not that many fluctuations in the milk supply. Therefore, only a few scenarios had to be planned for. The peak in milk supply is recurring each year and scenario planning is done each year to assure processing all milk. On the medium term, it is decided which business unit will process the extra milk, based on where they can earn the most. On a short planning horizon the organization looks at how much milk goes to each specific plant, based on availability of processing capacity. Observations in the meetings where medium and short term scenarios were discussed showed that all relevant stakeholders were present and actively discussed all scenarios and future trends. Interviewee 5 about case 3 “An analysis of scenarios is nice but it is useless if we afterwards no actions can be taken”. So based on the scenarios, plans are made on how to deal with those scenarios if they become reality. The need for these scenarios is highlighted by many interviewees. Interviewee 1 shows how this leads to velocity in case 2: ”We can react fast because in the plan you already point out where potential room is to process the extra supply, so you just run the list” and interviewee 3 confirms this by stating that: “What if scenarios are the most important, because as a consequence it ensures a fast response. So if there is something going on, you are immediately capable to react”. The organization was able to maintain functionality in this disruption because through the accurate proactive planning it was known beforehand how to minimize the impact of the event; the organization was prepared for it and thus did not have to go into crisis mode.
23 for. To increase data accuracy interviewee 4 states about case 4: “So we started preparing by asking from our suppliers what they think they will supply in milk once the quota is abolished”. This unfortunately was not an accurate indicator of milk supply thus the organization searched for other data available that would lead to more accurate forecasts, for example as interviewee 3 states “Then we started working with the amount of cows that were held, and we got a more accurate pattern”. Even though the organization had years to prepare for this event and put much effort in, the accuracy of their indicators on how much milk the suppliers were going to deliver were not good. It was observed as very important to have the visibility in the form of scenarios and forecasting as accurate as possible because the plan on the medium term planning horizon is the input for big decisions like planning revisions. When plants are allowed to do revisions or big overhauls, this severely impacts the total processing capacity of the supply chain. Interviewee 5 in case 4: “We can always decide to cancel a revision if there is no other option to process the extra milk, but this is very costly so we plan all revisions outside of the peak season”. These revisions were thus planned after the peak in case 4 but the peak came much later and took longer and that made maintaining functionality a lot harder since less capacity was available. In case 4, but also in other cases, the ability to process extra milk was very reliant on redundant capacity as a mitigation measure. If more data had been available and used, the scenarios would have been more accurate and the organization would have never planned revisions in the period of the peak.
Another example that shows the importance of scenarios is in case 3 with the fire in the cheese factory. The business unit did not have scenarios in place the milk of cows but a small part of the factory focused on the goat milk. Interviewee 6: “Milk you can assign to any plant in this organization but that does not hold for goat milk, so when the fire was there we immediately looked for an alternative”. While an alternative was found very fast, proactively listing alternatives would have increased the ability to act even faster.
The importance of visibility in the phase of maintaining functionality
24 what was all destroyed and what not”. Case 2, the peak in milk supply, demonstrates that visibility allows the supply chain to look for future opportunities and threats. Interviewee 3 explains that: “After the disruption the following question we ask ourselves is, if it is only for one day or more days that milk is coming in. Otherwise it is just acting in the moment and you rather look ahead”. Proactive plans, like scenarios, made beforehand increase the speed and ability of the organization to look ahead once a disruption has occurred. It creates a far-sightedness whereby the organization even spotted an opportunity to tackle the disruption (interviewee 1 in case 2): “We can see in our plans that next week we have more capacity available. What we do then is push the wave of milk to next week because then we have enough room as opposed to this week”. The opposite is observed in case 1, the fire. The first thing the organization did after the fire was create visibility. Right after the fire destroyed the plant the business unit executed a network study, increasing data availability, in order to make the best decision regarding the rebuild of the plant. Interviewee 6: “We did a complete network study on where to optionally build the capacity of this plant, at the same site or maybe build on to another factory? …… A lot of things we researched in the network study, we still use because now we are looking if we did have the right network at that time”. Although a lot of effort was made to make grounded decisions, if it would be known beforehand what the network looked like, this could have increased velocity in reacting.
4.2 Picking appropriate redundancy
25 best to be made when extra milk is supplied and invest in those capacities as redundant resource. Moreover, what has to be considered in proactively picking redundant capacity is the ability of that capacity to quickly process milk. Highlighted by interviewee 7 in case 4, the quota abolishment: “I don’t mind if a lot of work has to be done to process extra milk but it should not take too much work because if you have to have a lot of communication lines in short term and there will be noise on the line, the aimed goal of easy and fast processing will not be reached.” Certain business units are very complex in this business, due to complexity of the composition of products and interdependencies in the supply chain. The capacity in those business units is thus less applicable for redundant capacity. Interviewee 7 about case 2: “Processing milk in infant food is too much work; too many links to get it fast trough the supply chain.” An example of a very appropriate redundant resource is milk powder, interviewee 7 about case 2:“A product with you can keep on inventory for longer and it has a relative simple production process”.
26
4.3 Flexibility
Proactively using flexible measures, like outsourcing, also increases the profit made while maintaining functionality. In case 3, the capacity delay, this was observed. In the proactive planning phase the organization believed that capacity would be delayed, and thus they decided to sell milk in advance. Interviewee 2: “How we dealt with this is selling milk in long term contracts, than you get more money for the milk than if you would sell it on the spot market”. Proactively taking the measure of outsourcing milk has thus led to more profit than if they would have sold the milk at the time of the disruption on the spot market. In case 4, a lot of milk had to be sold on the spot market and great losses were made resulting in a lower form of maintaining functionality. It was observed in the crisis meetings that the ultimate measure is to sell milk on the spot market. From the notes of crisis meeting 1: “To deal with the huge amounts of milk supplied, the ultimate measure used in crisis is selling the milk at the spot market. The organization had to make sure the milk goes away and sometimes it was not even sold but paid for to be taken away”. The reason this is the ultimate measure is because it is the least profitable one. Proactively outsourcing milk on a long or medium term level before the disruption is positively influencing the ability to maintain functionality by lowering the amount of milk that needs to be supplied and doing this more profitable than selling it at time of the disruption.
In the reactive phase when trying to maintain functionality, flexibility was observed as a very important mechanism. In case 2 when the milk peak was really high the organization turned to making milk powder. In case 2, interviewee 2 explains that: “The way we dealt with the milk peak was a change but not an issue because we were able to shift to milk powder”. So the ability to shift between processing capacities is a form of flexibility and caused the event to not evolve into a disruption. This is observed as the most important measure in mitigating the impact of a disruption.
In case 3, the fire in the plant, the opposite is shown. Interviewee 6: “When the factory burned down, two molds of cheese could not be made anywhere else, so the whole production capacity of those molds ceased”. In this case functionality was medium maintained and one reason is that no redundant capacity was held in those molds, so flexibility to switch between plants was not possible. The consequence was that (interviewee 6) “On the moment that that capacity ceases, you cannot sell several cheeses anymore”.
27 case 3, the fire in the cheese factory, this becomes clear. If the mold was not a restricting factor for that type of cheese, because that mold could be made at other locations then (interviewee 6): “Other factories adopted the recipes and made those cheeses they usually not do”. Another example of how flexibility allows mitigating the impact of a disruption, without being reliant on redundant capacity is shown in case 4. Interviewee 5 about case 4: “Always more is possible, but do not ask the plants to do it for two months. And that is, I think, a part of flexibility, so you change the product-mix in the factory through which it absorbs more milk, you switch production plans etcetera”. These options named by interviewee 5 do require capacity, but the solution is in fact that by changing the use of existent capacity more milk can be processed than usual.
4.4 Accountability and ownership
In the theoretical background it is set out that robustness is based upon the three factors just discussed, visibility, redundancy and flexibility but a fourth factor was found in this case study. It must be noted that this factor is not on the same supply chain level as factors previous mentioned. Accountability and ownership is nonetheless observed as essential. All interviewees were asked what the three most important factors were in mitigating the impact of that disruption (see table 8 in appendix C), and in each of the four cases at least one interviewee stated accountability and ownership as a critical success factor in maintaining functionality. Interviewee 5 explains why employees in this organization are aware of the urgency to process all milk supplied: “We can mobilize personnel, I think because the farmer with its milk, the shareholder, that touches people, it is emotion. It is not an abstract shareholder, but a farmer with its family, an appealing goal to work for”. In a disruption a lot of flexibility is asked from the employees and the motivation of employees thus stems from being aware of the urgency to always process all milk supplied by the members.
Accountability in the proactive phase was observed as important in case 1, the peak in milk supply. This is a recurring event each year. Therefore it is very clear who the problem owners are because it has been established in previous events who is responsible for what and this rank in ownership still holds. Interviewee 3 about case 2: “It is very important that the problem owners are known, so it is clear who has to take action. First the operational level, if they cannot sort it out then the short term planner, and if he cannot sort it out then the supply chain director etcetera”. This makes it possible to react immediately if a disruption occurs.
28 a consequence of the quota abolishment, was much higher, came later and took longer than expected. In order to effectively mitigate the impact several crisis meetings were organized. Observations in those crisis meetings revealed that the managers of all business units were present and willing to help, like stated by interviewee 4 in case 4: “In times of crisis people are more focused towards one and the same goal. Usually you see people have their own agendas and in times of major crisis it is very clear what needs to be done and people start acting on that, it is solidarity”. Each stakeholders present knew where he was responsible for and how he could help. Employees on the operational level also showed ownership and accountability; from the notes of the second crisis meeting: “There was highlighted in the meeting that the signals they picked up from plants where positive, plants are willing to cooperate. They all stressed how important and positive this was”. Since these plants and all employees have to be very flexible it is important they feel ownership of the problem and thus accountable for help resolving. Interviewee 4 about case 4: “When it is crisis people have to act different and that sense of urgency is really important”. Through problem ownership in all relevant business units and making the crisis team accountable, grounded and fast decision making was made possible. The reason that functionality was maintained very well during the fire, case 1, is that a crisis team was assembled and made accountable for all decisions regarding this disruption. Interviewee 6: “The project leader got the freedom to make choices, whereby the rebuild of the plant was realized very fast. Not always the right choices are made then but a bad decision is better than no decision, in the end it did lead to the rebuild within two months”. This implies that autonomous crisis teams that get full time to focus on tackling an event leads to faster response and recovery, thus more velocity in maintaining functionality. Interviewee 6 states: “The crisis team operated completely parallel to the organization and had the freedom to do what they believe is right”. It was named as the critical success factor in rebuilding the plant that fast.
5. DISCUSSION
29 First, the case study revealed that proactive planning is indeed necessary to create an understanding of an organizations propensity for risk (Zsidisin & Wagner, 2010). Necessary because it makes the organization aware of potential risks and therefore it better knows how mitigate the impacts of risks. The proactive measures as mentioned by Thun & Hoenig (2011) to prevent disruption by tackling its cause (e.g. by reducing uncertainties by focusing on stable markets) turned out not to be applicable for every organization. Risk cannot always be avoided. Proactive planning seemed to be valuable in thinking about one’s vulnerabilities in a structured way, a first step towards a robust supply chain (Vlajic et al., 2013). Proactive planning is, though, considered more than only those proactive preventive measures. Like Tang (2006) argues a robust supply chain is useless unless a firm can execute the strategy in a proactive measure. The main benefit of proactive planning is namely found by already determining mitigation measures by reserving capacity, concerning both measures in redundancy and flexibility. This is in line with Wieland & Wallenburg (2012) stating that proactive processes and structures must be put in place to absorb risk. This is done by scenario planning, found to positively influence the velocity of response to a disruption, therewith increasing the ability to maintain function. Scenario planning was done for all disruptions that were foreseeable. Maintaining functionality during an unforeseeable disruption was secured by putting mitigating measures in place for unexpected events. In the proactive planning phase of scenario planning always a certain amount of the forecasting was seen as risk in case an unexpected event occurred.
30 overlooked. Additional to the research of Christopher & Peck (2004) that states visibility is needed to gain knowledge about actual changes that are currently occurring, visibility is thus also needed in proactive planning to choose appropriate measures and establish the capability of far-sightedness.
Redundancy was the most used mitigation measure in this case study and that is in line with Durach et al. (2015) who state it is the most cited category of supply chain robustness. Redundancy is often cited as redundant inventory in literature, but because in this case study the business was supply driven and redundancy thus meant extra processing capacity. A key problem of these techniques is that creating redundancies brings along inefficiencies (Thun & Hoenig, 2011). Maintaining functionality turned out to be more than just processing all milk but also doing this in the most profitable way, this is in line with Klibi et al. (2010, p. 290) who state that a supply chain is robustness if capable of providing sustainable value creation under all plausible future scenarios. It was observed that by proactively investigating which redundancies are most profitable to use, these inefficiencies can be limited. The most appropriate form of redundancy is in the capacity that has a simple production process and the products can be sold easily. This increased the velocity of processing the supply made maintaining functionality less costly. The case study revealed another way to overcome the inefficiencies. For the most part it can be overcome by combining redundancy and flexibility; building redundant capacity that can also produce products that the organization has planned to sell in a long term strategy. The capacity is thus in more than one way deployable. In this way redundancy is a way to flexibility (Jüttner & Maklan, 2011). In general, this case study confirms the research of Jüttner & Maklan (2011) who state that hedging through redundancy positively impacts velocity.
Flexibility is often reliant upon the available redundant capacity and this is in line with Rice & Canatio (2003) who state that a resilient supply chain can be created by using reactive instruments that increase flexibility as well as build up redundancies (Rice & Caniato, 2003). The scenario planning lead to quickly being able to switch between (redundant) capacities, flexibility prevented the process from being too finely-tuned that they may not be robust enough to absorb input disruptions without bending or breaking (Christopher & Rutherford, 2004).
31 level of robustness and agility required for the competitive strategy (Wieland & Wallenburg, 2012).
Lastly, this case study observed another aspect of great importance to supply chain robustness enhancing the resilience of a supply chain. In supply chain robustness literature this has not been stated before but this does not detract from the relevance. Accountability and problem ownership have been observed to be a main driver for the organization to collaborate and be flexible, enhancing the velocity in response. With problem ownership is meant that the employees in the organization feel responsible for their job and that it is known who is responsible for which part. It acts as the glue that holds a supply chain together in a crisis (Richey, 2009). In the proactive planning phase it was determined who was responsible for what, this leads to more velocity in the response. During the phase of maintaining functionality, accountability was just as important. Some disruptions cannot be predicted and there are thus many cases in which responses to disruptions cannot be prescribed in a well-defined process, where there is a need for situational awareness (Sheffi & Rice, 2005). Accountability entails that in times of a disruption one team is accountable for all decisions that need to be made in the first response phase and preparation for recovery phase of Sheffi & Rice (2005). In the case study, this crisis teams seemed highly effective by allowing a quick response to a disruption and increase flexibility of personnel. Stated by Sheffi & Rice (2205) is that this kind of initiative must be at levels closest to the event and furthest form the headquarters strategic planners (Sheffi & Rice, 2005). Culture is a recurring topic in the study of supply chain robustness and resilience, but often literature then aims on the risk management orientation (Jüttner & Maklan, 2011) and this research adds accountability and ownership to that. The reason that the relevance of this new aspect of supply chain robustness is stressed is because it was observed as one of the most important factors of being robust across all cases.
32
Flexibility Redundancy
Supply chain robustness
Visbility
Good forecasting and scenario planning
Prevent disruption and velocity in response
Pick appropriate and most profitable redundancy
measures
Velocity in response at minimum costs
Use flexible measures in advance like outsourcing
Decrease impact of disruption and more profit
Proactive planning Maintaining functionality Transparancy by sharing plans
Effort and flexibility of stakeholders
Esthablish flexible redundant capacity
Velocity in response and less risk in investment in
redundancy
Alternative use of capacity; change product mix or
production process Velocity in evaluation actual status disruption
Know problemowners Accountability
Ownership Velocity in response
Autonomous crisis team inreases velocity of
response
33
6. CONCLUSION
The aim of this article is to answer the research question: How does supply chain robustness enhance supply chain resilience?. Authors agree in literature upon the fact that robustness contributes to a supply chain being resilient. How exactly supply chain robustness enhances supply chain resilience has not yet been addressed in literature and this will be the contribution of this article. How supply chain robustness enhances resilience will be explained in the following paragraphs.
In the theoretical background it has been argued that the factors constituting supply chain robustness are visibility, redundancy and flexibility. In the research these three factors appeared to be indeed essential. Supply chain robustness is important in the proactive planning phase and to maintaining functionality. The circumstance of uncertainty in supply affected the ability of accurate proactive planning. Visibility, in the form of data availability and accuracy, was found to be a pre-requisite for effective proactive planning. Actions important in the proactive planning phase are forecasting, scenario planning and already picking appropriate mitigation measures to use in case of a disruption. It was observed that those activities in the proactive planning phase enhance maintaining functionality especially by increasing the velocity of response to a disruption. Next to those effects, proactively considering mitigation measures also caused that functionality was maintained in a more profitable way in comparison to only using reactive measures.
A surprising result of this research was that a new factor was discovered that is highly important in supply chain robustness, accountability and problem ownership; present in establishing crisis teams with full autonomy and in creating awareness of the urgency throughout the whole supply chain. Clear accountability and full end-to-end ownership increased the velocity and flexibility in maintaining functionality. Accountability and ownership, in the proactive phase and in maintaining functionality, also contributed to collaboration because it creates a bond between all parties of a supply chain to help each other out in times of need.
6.1 Managerial implications
34 planning is not merely to prevent the risk from happening but also entails preparing for a (unexpected) disruption happening. The manager should consider all options of possible mitigation measures like redundancy or flexible measures like outsourcing and determine which measures are able to solve the disruption the quickest and with minimum costs. Furthermore, it is important to create an attitude of far-sightedness in an organization and retain this attitude also after a disruption has occurred. Keep looking ahead in times of crisis, an opportunity to resolve the disruption or a threat increasing the impact of the disruption might lie ahead. Secondly, an organization has to create awareness and a sense of urgency amongst its personnel of the need for supply chain robustness and resilience. Therewith employees create a feeling of ownership and this enhances the collaboration and flexibility of an organization. In the phase of maintaining functionality a crisis team should be set up immediately and given the full responsibility, even better would be if the problem owners are indicated beforehand.
6.2 Limitations and suggestions for further research
36
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