=Paper=
{{Paper
|id=Vol-2574/short20
|storemode=property
|title=Augmenting Value Stream Mapping by Possession, Ownership and Availability (short paper)
|pdfUrl=https://ceur-ws.org/Vol-2574/short20.pdf
|volume=Vol-2574
|authors=Pavel Hruby,Christian Scheller
|dblpUrl=https://dblp.org/rec/conf/vmbo/HrubyS20
}}
==Augmenting Value Stream Mapping by Possession, Ownership and Availability (short paper)==
https://ceur-ws.org/Vol-2574/short20.pdf
Augmenting Value Stream Mapping1 by Possession,
Ownership and Availability
Pavel Hruby and Christian Vibe Scheller
phruby@acm.org, scheller2@msn.com
Abstract. Value stream map (VSM) is a special type of flow chart used in lean
manufacturing to depict and improve the flow of material and flow of
information. Possession, ownership and availability (POA) is a modeling
framework for design of enterprise information systems using flows of
economic resources in enterprises or business ecosystems. This paper compares
these two modeling techniques and identifies the benefits of using value stream
mapping augmented by the POA semantics.
1 Introduction
Value stream map (VSM) is a special type of flow chart used in lean manufacturing to
depict and improve the flow of inventory and flow of information (Storch 2010). The
purpose of lean manufacturing is to make the flow more efficient by minimizing
waste, such as wasted time, unnecessary motion, or excess inventory. A value stream
map is a graphical representation of the value stream, including material and
information flows. It shows the flow of steps in product management and information
systems that support value-adding activities.
The Possession, Ownership and Availability (POA) modeling framework (Scheller
and Hruby 2016) represents the creation, flow, and consumption of economic
resources, expressed as flow of possession, flow of ownership and flow of
availability.
The POA model also shows the flow of steps in product management and
information systems the support value-adding activities, but from a different
perspective than value stream mapping.
In this short paper we provide an example of a simple manufacturing process
represented both in the value stream map and in the POA model. We will compare
differences between them and illustrate areas where the value stream map would
benefit from considering adding the POA semantics to the value stream map.
2 Concepts
Concepts such as flows, value and information have different semantics in the value
stream map and in the POA model.
1 Acknowledgement: The authors would like to thank to Paula Lipnick of DXC Technology
for valuable feedback on the draft version of the paper, and for very useful suggestions for
further research.
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Copyright © 2020 for this paper by its authors. Use permitted under Creative Commons License
Attribution 4.0 International (CC BY 4.0).
Augmenting Value Stream Mapping by Possession, Ownership and Availability
Value
In the value stream map (VSM), the value is a capability provided to a customer,
defined by the customer (Storch 2010, Martin and Osterling 2013). Examples are
quality, right time of delivery and appropriate price, and can be measured absolutely
using the quantities of contributing features. The VSM value definition carries a
certain aspect of contract negotiation – if we deliver you the quality, at the right time
and at appropriate price, would you buy? It might indicate that VSM is primarily
targeted to business-to-business scenarios rather than to business-to-consumer, where
it is often difficult to find how the consumer determines the value.
The value of an economic resource in the POA model is determined by observing
the exchange processes, and cannot be measured absolutely, only relatively, by
comparing the value of the resource to the values of other resources at the time of
exchange. For example, when Elwood of Blues Brothers traded Cadillac for a
microphone, under the given circumstances the microphone had higher value for
Elwood than the Cadillac, which Jake of Blues Brothers acknowledged: “OK, I can
see that” (Dendis, 2011, Wilson 2018). From the POA model we cannot determine
whether Elwood wanted microphone because of quality, time of delivery and
appropriate price; the only fact the POA model tells us, is that the microphone had
higher value than the Cadillac at the time of exchange.
Both approaches are useful. Using the VSM definition, knowing what features of a
product are valuable for the customer, helps to design the product the customer might
eventually buy. However, using the POA definition, we cannot be sure that the
product has any value for the customer, until the customer actually buys it.
Flow
A flow in the value stream map is an “item” that flows through a value stream (Storch
2010). Examples are materials in manufacturing processes, designs in design and
development processes, external customer needs in service industry, and internal
customer needs in administrative processes.
In the POA model, a flow represents the transfer of possession, ownership, or
availability of an economic resource from one role to another, or the creation or
consumption of an economic resource (Scheller, Hruby, 2016). A flow can also be a
flow of information from one role to another, see below.
Information
In the value stream map, the information flow is not precisely defined and is specified
only intuitively, and focuses on the actual mechanism of delivering information,
rather than what the information actually means in the context of the analyzed
process.
In the POA model, information is an economic resource. Consequently, a flow of
information is a flow of possession, ownership and availability of information from
one role to another. Information is special, compared to other economic resources,
because a provider can send information to a recipient without losing it. In other
words, a flow of information does not change the possession, ownership, or
availability of that information for the provider, but does make the information
available (and optionally owned and possessed) to the recipient.
Other concepts
The value stream map can contain several other concepts such as timeline, showing
value-adding times (cycle times) and non-value adding (waiting) times; inventory,
shipment, material push flow, material pull flow, kaizen burst, highlighting the need
for improvement, glasses icon, indicating visual gathering of information, sticky man
for verbal communication, wiggle arrow indicating electronic communication, solid
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Augmenting Value Stream Mapping by Possession, Ownership and Availability
line for manual flow of information such as memos, and reports, and a number of
icons related to Kanban, such as Kanban signal, Kanban post, Kanban stockpoint.
Some of these concepts are illustrated in Fig. 1
Main POA concepts are economic agents, roles, economic resources, repositories
and flows of possession, ownership and availability of the resources. The full list of
concepts is included in the POA metamodel in (Scheller, Hruby, 2016).
To summarize, the value stream map focuses mainly on the actual mechanisms
supporting and enabling the material and information flows, while the POA model
focuses on their economic semantics.
3 Example of a Manufacturing Process in VSM and POA
Example of a manufacturing process in the value stream map is illustrated in Fig. 1. A
manufacturer delivers metal foils on Tuesdays and Thursdays. The metal foil is
stamped, assembled, packed and dispatched the Customer/Recipient. Manufacturer
deployed an MRP system for production control, that receives 90/60/30 day forecast
and a daily order from the Customer/Recipient, sends 6-week forecast and weekly
order to the Supplier, and produces weekly schedule for the stamping and assembly
stations, and a daily ship schedule to the pack-and-shipping station.
90/60/30/day
6 week Forecast
Forecast
Production control electronic
electronic Recipient /
Customer
Supplier
electronic
o MRP Product
Raw material 12.000 pcs/week
Weekly Daily order
order
Weekly schedule
Tuesdays &
Daily ship 1 daily
Thursdays
schedule
Stamping Assembling Pack and dipatch
Inventory
Inventory Inventory
6
5 days 70
Cycle time = 1 s Cycle time = 62 s
Changeover time = 1 hour Changeover time = 10 min
Staff = 2 Staff = 4
5 days 2 days 4,5 days Production lead time 11,5 days
1 second 62 seconds Value added time 63 seconds
Fig. 1. Example of a manufacturing process in value stream map
Example of the same process represented using Possession, Ownership and
Availability concepts is illustrated in Fig. 2. Information from the value stream map,
which cannot be represented using core POA concepts, is depicted by the UML Note
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Augmenting Value Stream Mapping by Possession, Ownership and Availability
symbol; an example is the information that Supplier delivers on Tuesdays and
Thursdays.
Activities in the POA model are instantaneous (have zero duration), therefore, in
the POA model, start and end of each manufacturing operation must be represented
explicitly. It is also necessary to explicitly represent the resources consumed and
created by each activity, for example, the Start Stamping activity consumes the metal
foil and creates the temporary “in-stamping” resource. The Finish Stamping activity
consumes the “in-stamping” resource and produces the stamped widget.
While the operation symbol in the value stream map indicates how many workers
(staff) are required for the operation, the well-formed POA model must be more
precise. Labor in the POA model is an economic resource created by Worker agents
and is related by the “usage” relationship to the start and to the end of each
manufacturing operation. The repository Labor (work day) represents the total
available time of the Workers, while the start and end of each manufacturing
operation represent the actual value-adding time of the used Labor. The value stream
map in Fig. 1 does not illustrate utilization of labor, in contrast to the POA model.
«availability» «availability»
1 daily
Metal foil (6 week forecast) Product (90/60/30 day forecast)
«availability»
Metal foil (Weekly order) «possession»
«availability» product
Unload
Product (daily order)
Recipient/
Supplier «ownership» «possession»
Tuesdays & 12000 pcs / week Customer
«possession» Thursdays product Product
«ownership» Manufacturer
Metal Foil «availability»
Product Carrier
«availability»
«availability»
Assembled Product
Metal Foil Metal foil (Weekly schedule)
(Daily ship schedule) «possession»
Receipt Product
«availability»
«availability» «availability» Assembled product
«possession» Stamped widget Stamped widget Load
(Weekly schedule) 6 pieces
«ownership»
Metal foil Consume
Metal foil «ownership, possession»
70 pieces In packning Product
and
In Packing and
Waiting for In Stamping In Assembly Dispatching
Consume Waiting for Consume¨ Waiting for Dispatching
Stamping Process Stamped Process
In stamping Assembly In Packing Process In packning
widget
assembly Assembled and
In stamping In stamping In assembly In assembly product Dispatching
Stamped Start Packing Finish Packing
Assembled
Start stamping Finish stamping widget Start assembly Finish assembly and Dispatching and Dispatching
Consume product
Stamped
Widget Use Consume Use
Use Assembly Create Assembled Packing
Worker Labor Use Use machine Assembled Product machine Create
Create Create Create
StampingStamping Use product Use Product
In stamping Stamped In assembly Assembly
machine machine Create Packing
Use widget
machine In packing and machine
Labor Consume
Create dispatching In packing
Cycle time = 1s
Labor Consume Stamping Changeover time = 1 hour and dispatching
Labor machine Assembly Cycle time = 62 s
Machine Changeover time = 10 min Packing
machine
Use Labor
Labor
Use Labor
(work day)
Use Labor
Use Labor
Fig. 2. Example of a manufacturing process using possession, ownership and availability
Another interesting observation is that the information flows (forecasts, weekly and
daily orders), as well as the weekly and daily schedules in the value stream map in
Fig. 1, are actually flows of availability of material, in the POA terms.
It illustrates the importance of determining the economic semantics of the
information flows. The POA model has a consistency rule that when a resource is
created, the possession, ownership and availability of this resource are created with it,
likewise, possession, ownership and availability no longer exist after the resource is
consumed. Therefore, an activity consuming a resource must have incoming flows of
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Augmenting Value Stream Mapping by Possession, Ownership and Availability
possession, ownership and availability of this resource, otherwise the resource cannot
be consumed.
Applying this rule leads to a discovery of flows not present in the VSM model in
Fig. 1, but which are necessary for the completeness of the model from the economic
perspective. For example, there must be a flow of availability of Stamped Widget
resource to the Manufacturer, otherwise the Manufacturer would not be able to
transfer this availability to Start Assembly activity, which needs it in order to
consume Stamped Widget. The flows of resources discovered in this way are
indicated in red color in Fig. 2.
During process improvement we can then start thinking whether this flow of
availability must go through a central planning system or can be transferred directly to
the next manufacturing operation, which could then start immediately after the
previous operation finishes, which could in some cases lead to shorter waiting time
and leaner process.
4 Information Model
The main purpose of the POA model is to create an enterprise information system,
from the model of the flows of economic resources in the business ecosystem. Hruby
and Scheller (2019) illustrated that occurrence of each flow at runtime represents an
information that is useful to potentially all stakeholders in the ecosystem and can be
forwarded to them. For example, the information about arrival of metal foil to the
inventory can be also made available to the stamping, assembly, packing stations and
perhaps even a Recipient/Consumer, which might get valuable signals about changes
in the manufacturing processes. For example, when Samsung in 2016 stopped placing
orders for components of 3D glasses, it was a useful signal for the consumers that
Samsung is stopping producing 3D TV sets, although Samsung has not announced it
publicly.
The number of information flows generated this way is proportional to the number
of flows multiplied by the number of stakeholders; this amount of information in any
larger system can no longer be handled manually and requires a digital solution.
5 Conclusions
Although the value stream map is an informal diagram, understanding the economic
semantics of the material and information flows helps to make the process leaner and
eliminate waste by discovering and enabling additional information flows between
processes and trading partners, allowing them to adapt at runtime to the deviations
from the schedules. Making the information instantly available where needed and
when needed, requires a digital information technology solution.
Therefore, value stream mapping, in its traditional form, is a valuable tool in
situations when digital information processing is not possible or desirable and when
information must be fully or partially processed and transferred manually. If it is
feasible to fully or partially automate the value stream and implement a digital
information system, augmenting the value stream by possession, ownership and
availability allows to design an information system better supporting the lean business
processes.
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Augmenting Value Stream Mapping by Possession, Ownership and Availability
6 References
Martin K, Osterling M (2014) Value Stream Mapping: How to Visualize Work and Align
Leadership for Organizational Transformation. McGraw Hill
Dendis, W (2011) The Blues Brothers - You traded the Cadillac for a microphone
https://www.youtube.com/watch?v=nrKmNkDcDuk
Hruby P, Scheller C.V (2019) Device as a Service – an Economic Model, Value Modeling and
Business Ontology (VMBO) workshop, Stockholm, Sweden, March 4-5, 2019
Lipnick, P (2019) Value Stream Mapping Next Practices, ADaPT 2019 – Agile DevOps and
Product Thinking, FCA, December 2019
Rother M., Shook J (1999) Learning to See: value-stream mapping to create value and
eliminate muda. Brookline, Massachusetts: Lean Enterprise Institute
Scheller C.V, Hruby, P (2016) Business Process and Value Delivery Modeling Using
Possession, Ownership, and Availability (POA) in Enterprises and Business Networks.
Journal of Information Systems: Summer 2016, Vol. 30, No. 2, pp. 5-47.
Storch, R.L (2010) Value Stream Mapping, University of Washington,
https://courses.washington.edu/ie337/Value_Stream_Mapping.pdf
Skillsoft (2019 Applying Value Stream Mapping in Lean Business,
https://cdnlibrary.skillport.com/courseware/Content/ria/RIA_V3_1_2237/
Wilson, N. (2018) Why did Elwood trade a Cadillac for a microphone?
https://movies.stackexchange.com/questions/47210/why-did-elwood-trade-a-cadillac-
for-a-microphone, https://www.youtube.com/watch?v=nrKmNkDcDuk
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