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Transcript of Order Fulfillment - WueCampus2 · For a number of companies, so-called “online configurators”...
Remember!
2
Monitoring/Event Management
MaterialsManagement Production
PlanningSales & Distribution ERP*
Purchasing
*Relevant modules for Supply Chain Management
Strategic Network Design
SC Master Planning
Material Requirements
Planning&
Purchasing
ProductionPlanning
DistributionPlanning
SchedulingTransportation
Planning
DemandPlanning
OrderFulfillment
APS
Pla
nn
ing
Ho
rizo
n
Monitoring/Event ManagementMonitoring/Event Management
MaterialsManagement Production
PlanningSales & Distribution ERP*
Purchasing
*Relevant modules for Supply Chain Management
MaterialsManagement Production
PlanningSales & Distribution ERP*
Purchasing
MaterialsManagement Production
PlanningSales & Distribution ERP*
Purchasing
MaterialsManagement Production
PlanningSales & Distribution ERP*
Purchasing
*Relevant modules for Supply Chain Management
Strategic Network Design
SC Master Planning
Material Requirements
Planning&
Purchasing
ProductionPlanning
DistributionPlanning
SchedulingTransportation
Planning
DemandPlanning
OrderFulfillment
APS
Strategic Network Design
SC Master Planning
Material Requirements
Planning&
Purchasing
ProductionPlanning
DistributionPlanning
SchedulingTransportation
Planning
DemandPlanning
OrderFulfillment
APS
Strategic Network Design
SC Master Planning
Material Requirements
Planning&
Purchasing
ProductionPlanning
DistributionPlanning
SchedulingTransportation
Planning
DemandPlanning
OrderFulfillment
APS
Pla
nn
ing
Ho
rizo
nP
lan
nin
g H
ori
zo
n
You are here!
Learning Objectives
• So far, we have addressed planning problems that occur upstream
relative to the decoupling point (i.e., that are based on forecasts)
• Now, we consider decisions that have to be taken downstream (i.e.
when customer orders/demand have materialized)
• Once customer orders/demand are known, we have to decide how
to best fulfill them given our available supply (i.e., capacity &
inventory) – this is commonly referred to as “order fulfillment” or
“demand fulfillment”
• After completing this part of our course, you should
• Know the basic tasks and functionalities of order fulfillment (systems)
• Understand key objectives and relevant trade-offs
• Know different modes of order fulfillment and when they should be employed
• Have a thorough understanding of the logic of order fulfillment systems and
state-of-the-art quantitative methods
• Have a good knowledge of how to cope with stock-out situations 3
Order Fulfillment
…balances supply and demand in the short run
• Some example (industry) problems:
Dell receives a customer order for 20 high-grade servers. For when should they promise
delivery?
An OTC pharmaceuticals company runs short on stock. Which customers should receive their deliveries first, which customers have to wait?
A hard disk manufacturer runs short but has the option to „upgrade“ or expedite certain orders. Should the manufacturer do so?
Alcatel-Lucent has promised certain customers a specific service level for DSL equipment. How much capacity and inventory should they reserve for these customers?
A paper manufacturer wants to incentivize customers to order earlier. What should they offer?
4
Important to understand: Decoupling Point
5
Fleischmann/Meyr, 2003
Order fulfillment occurs downstream (i.e., on the right hand side)
of the decoupling point
Order Management/Order Fulfillment
The order fulfillment process includes all
relevant activities from placing an order by the
customer to its fulfillment/completion
• Objectives
Enable easy to use (electronic) order placement and
order entry
Short response time to customer orders and
requests,
Promise reliable due dates and ensure on time
delivery
“Optimal” allocation of orders to resources
(administrative resources, inventory,
manufacturing, distribution and transportation
resources)
Order Entry
Order Promising
Scheduling
(Production)
Execution &
Monitoring
Scheduling
(Shipping)
6
Different Terms
Note: different terms are being used in industry and academia, which
are not precisely defined and are often overlapping:
• Order fulfillment
• Demand fulfillment
• Order management
• Order promising
• Available to promise (ATP)/Capable to promise (CTP)/Profitable to Promise
(PTP)
• Due date Quoting
7
The Fulfillment Process
8
Order entry
Customer order
received
Order has been
entered
Check availablitiy
Order has been
confirmed
Execution and
monitoring
Order fulfilled
Reuested
quantity
is available
Quantity not
available on
time
Determine alternative
strategies
Alternative
strategies
determined
XOR
Confirm order and
delivery dates
XOR
Tasks and Objectives
Tasks of order fulfillment systems:
• Receive/handle orders coming in through multiple channels
• Quote due-dates/deliver dates (order promising)
• Reserve capacity/schedule order
• Order execution and monitoring/rescheduling
Objectives:
• Enable easy to use electronic order placement and order entry
• Short response time to customer orders and requests
• Ensure on time delivery
• “Optimal” allocation of incoming orders to inventory, manufacturing, distribution and
transportation resources
To which criterion/criteria does the term “optimal” refer to?
9
Receiving Orders
Today, systems have to be able to support order entry through:
• conventional channels (fax, e-mail)
• phone (call center support)
• website
• Electronic Data Interchange
For a number of companies, so-called “online configurators” are essential to their business model (ATO/MTO)
• Most prominent: Dell, started in 1996
• Features include
compatibility constraints
quoting
approximate delivery time
Although still relatively young, these functions are now mature; state of the art systems are fairly easy to implement and run stable
10
More Interesting: Order Promising
Relevant questions:
• When can we fulfill an order?
• Are we meeting the customer’s requirements in terms of delivery times?
• What can we do if we cannot meet the customer’s requirements? Any alternatives?
• If we have alternatives, how much do they cost us? Is the customer worth the additional cost?
• In upcoming stock-out situations, which customer orders are fulfilled, which orders are rejected or have to wait? What are short and long term consequences?
Order promising links sales and CRM to core SCM functions (manufacturing, inventory management, distribution)
11
Order Promising
Let’s have a closer look at the order promising process described previously
12
Check availablitiy
Reuested
quantity
is available
Quantity not
available on
time
Determine alternative
strategies
Alternative
strategies
determined
XOR
Confirm order and
delivery dates
XOR
Conventional ATP
13
Conventional “Available to Promise” (ATP) implemented in ERP
Provides information on uncommitted portion of inventory on hand + master schedule
Simple bookkeeping function:
t=1 t=2 t=3
Initial inventory 100
Planned receipts 300 500 500
Committed quantities 200 400 200
ATP 200 300 600
ERP module: PP
ERP module: MM
ERP module: SD
Order Promising – Make to Stock
Slightly advanced order promising includes:
• Simultaneous allocation of orders to ATP quantity and due date quoting
• When can an order of size be fulfilled?
• Most commonly, due date quoting against available to promise inventory is called ATP
• Easy to implement standard function
14
ATP
t
Order Promising – Assemble to Order
ATO order promising includes:
• Simultaneous allocation of orders to component ATP quantities and due date quoting
• When can an order be fulfilled if?
• capacity and quantities
• of A,B,C are required?
• Capacity and all components can be bottleneck
• Most commonly referred to as Capable to Promise (CTP)
• Relatively easy to implement standard function
15
t ATP Component B
t ATP Component C
t Assembly Capacity
ATP Component A
Order Promising – Make to Order
If we want to consider a multi-stage production process, order promising gets
very complicated if bottlenecks can occur on more than one stage
If only one bottleneck, ATO logic can be applied
We will look at MTO order promising later
16
Real-Time Order Promising (1)
Real-time order promising
• For every incoming order, delivery dates are immediately quoted
• Customer instantly receives information about availability and expected delivery date
17
21 1 1
ˆ( , );q d d
42 2 2
ˆ( , );q d d
315 15 15
ˆ( , );q d d
116 16( , )q d
Incoming Orders
Allocation of resources; due date quoting
16d̂
Order book (with quoted due dates)
Inventory of component mM
t
t
Capacity
invm,t
capt
1, ,, ,
1, ,
min ,..., ,d M d d
p d dp M p p
inv inv capctp
Real-Time Order Promising (2)
Real-time “Capable to Promise” (CTP) algorithm:
Quantity of product p that can be produced in time interval [tb+1,d]
Inventory component 1,…,M in period d
Capacity in period d
Resource coefficients for product p
, , ,1
b
d
p d p t dt t
ctp ctp
1, 1 , 1 1, ,, ,
1, , 1, ,
min ,..., , ,..., ,
net nett M t t M t t
p t dp M p p M p p
inv inv inv inv capctp
1,..., 1bt d t
, 1,..., 1bm M t d t
,for 0m p
18
, , , 1 , , ,min ,net netm t m t m t p t d m pinv inv inv ctp
pmddpdm
net
dm ctpinvinv ,,,,, γ
Batch Order Promising (1)
First we collect all incoming orders during a “batching-interval”, e.g. one day
At the end of the batching-interval, orders are allocated to inventory/
capacity and due dates are determined
19
Order book
(end of batching-
interval)
1 2 15ˆ ˆ ˆ, ,...,d d d
Inventory of component
mM
t
t
Capacity
invm,t
capt
Allocation of resources;
due date quoting
21 1( , )q d
42 2( , )q d
315 15( , )q d
21 1 1
ˆ( , );q d d
42 2 2
ˆ( , );q d d
315 15 15
ˆ( , );q d d Order book
(with quoted
due dates)
Order Promising – Real Time vs. Batch
„It should be noted that there are very few true real-time ATP systems operating today;
most systems that give an immediate response (including most web-based retail sites)
produce an initial „soft“ promise, run a batch module later and then produce a „hard“
promise.“
(Ball et al., 2002)
What are the advantages/disadvantages of real-time and batch order promising?
When employing batch order promising, the length of the batching-interval is a decision variable
We will look at models supporting batch order promising!
20
Batch Order Promising (2)
Alternative mechanisms:
• sequential (e.g. first come first served, highest priority first)
• optimization models
Let’s look at a simple optimization model
21
Batch Order Promising Model – Notation
22
,pi tx
,,p cumi tx
,
1 if order is shipped in
0 elsei t
i ty
1 if order is promised
0 elsei
iz
,pi tx
i
,( )i i tc y
Additional variables
production quantity product p for order i in period t
cumulated production quantity for order i in period t
quantity shipped for order i in period t
Additional parameters:
profit margin order i
penalty cost if order cannot be fulfilled
Active vs. Passive Order Promising
Passive order promising
• Utilizes information about available inventory/capacity for due date quoting
• Returns due dates for execution to manufacturing, warehouse management, and
distribution systems
• Does not generate detailed schedules for order execution (e.g. manufacturing
schedules)
Active order promising
• Utilizes information about available inventory/capacity for due date quoting
• Simultaneously determines schedules for execution (e.g. manufacturing schedules)
When are active/passive systems feasible?
What are the advantages/disadvantages?
25
Classification of Order
Promising Types and Methods
26
Aktive (A) Passive (P) Active (A) Passive (P)
Execution Level
Availability Level
Finished goods Resources
optimization models ? ?
Rea l- time (RT)
- time
Batch (B)
Response
disposition rules disposition rules RT/R/A
B/R/A
Simultaneous generation
of due dates and
schedules
RT/R/P
B/R/P
Determiniation of due dates
first, then scheduling
RT/FG/A RT/FG/P
B/FG/A B/FG/P
disposition rules disposition rules
optimization models ? ?
Search rules in case of shortage
27
Search rules for supply alternatives:
(„Rule-based search“, „Multi-dimensional search“), e.g. SAP-APO:
4
2
3 1
Products
Locations
CTP
2
3
4
1 substitute products
same product at other
locations
substitute products at
other locations
CTP: create new
supply order
Order Promising with substitute products
In certain cases substitute products can be delivered instead of the product,
originally ordered by the customer
Depends on the availability of a product acceptable to the customer
Customer will only accept the substitute if it provides at least the same utility as
the original, and if its use is not limited, e.g. by technical restrictions
Necessary to determine additional fulfillment cost. Do we really want to carry
these?
28
Order Promising with multiple locations
If order cannot be fulfilled with the finished goods or capacity at a certain
location, order can be shifted to other locations
Order promising is then applied to a distribution or manufacturing network
rather than only to a single location
Multi-location order promising should take different manufacturing and
transportation lead times and costs into account
29
Order Promising with partial deliveries
If ordered quantity is not available within requested delivery time window, order
can be fulfilled with two or more partial deliveries
First partial delivery should be scheduled within the given time window
Customer must agree to partial deliveries
If partial deliveries are possible, then order promising should determine the
quantities and delivery dates for each partial delivery
Necessary to determine additional fulfillment cost. Do we really want to carry
these?
30
Assessment of Fulfillment Alternatives
The previously outlined “Add-ons” can be utilized in case of temporary stock-
out situations
They can be employed simultaneously and can also be combined (Note the
increase in complexity)
System should then be able to assess the fulfillment alternatives in terms of
• fulfillment cost
• customer satisfaction?
Critical question: How well does a system support generation and assessment
of these fulfillment alternatives?
31
Order Promising/Fulfillment in hierarchies
• So far, we have mainly looked at order fulfillment for a
single location
• In many companies, however, we find different geographical
(sales) regions across which product quantities are first allocated
in a hierarchical manner
• The allocated quantities are the basis for order promising
• In the following we will address this problem and see how this is
handled in SAP APO
• Slides come from Kilger/Meyr, Chapter 9 in
Stadtler/Kilger (2010)
32
The Customer Hierarchy
To allocate supply to customers the following is required:
• a model of the customer structure
aligned with the geographic dimension in demand planning
• a forecast of the future customer demand
33
Forecast
Aggregation World-wide
Sales
America Europe
Germany France Italy
West East
200 200
400 200
400
1400
400
1000
top
area
region
country
1400
The allocation process – first step
• Aggregate all forecast quantities to the root of the hierarchy.
• This gives the total forecast of the specific product (or product
group).
• Transfer total forecast to Master Planning (MP) to check which
portion of the forecast can be fulfilled.
• Example: 1400 total forecast; 1200 can be fulfilled (according to
MP)
34
The allocation process – second step
Allocate MP quantity top down to the leaves of the customer hierarchy
This top-down allocation is controlled by allocation rules:
• rank based:
higher priorities (ranks) between customers
available quantity is allocated to higher rank up to the original forecast
helpful to support sales to specific markets
• per committed:
allocation according to the forecast the customers have committed to
split appropriate to the fraction of the original forecast
support a „fair share“ allocation according to the forecast
caution: rationing gaming may occur !
• fixed split:
apply predefined split factors
independent of the individual forecast 35
Example for second allocation step
36
ATP
Allocation
World-wide
Sales
America Europe
Germany France Italy
West East
split 0.7
224 (200)
320
(400)
160
(200)
rank 1
400 (400) 1200 (1400)
320 (400)
800 (1000)
top
area
region
country
1200 (1400)
rank based
per committed
fixed split
rank 2
800 (1000)
split 0.3
96 (200)
Search process
General ATP-based order promising process:
• search for ATP according to a set of search rules
• if ATP is found
reduce accordingly and generate a quote for the order
• if no ATP is found
no quote is generated and the order must be rejected or confirmed
manually at the end of the allocation planning horizon
(SC is not able to fulfill the order within the allocation planning horizon)
ATP is searched along several dimensions (as shown before)
• time dimension
• customer dimension
• product dimension
37
Example of an ATP search procedure
38
America Europe
Germany France Italy
West East
World-wide
Sales
2. Customer
3. Product
1. Time
Three dimensions of ATP search paths
Request
Search rules for example
Following search rules are applied:
(assume that ATP is on finished goods level)
1. The leaf node in the customer hierarchy, to which the customer belongs, the
product being requested by the order and the time bucket containing the
customer requested date are determined.
ATP at this point is consumed – if available
2. If ATP is not sufficient, then the time dimension is searched backwards in time
for additional ATP (still for the same customer and product)
all ATP found up to a predefined number of time buckets back in time is
consumed
(consumption in earlier time buckets leeds to pre-built of an order = inventory)
3. If ATP is not sufficient, steps 1. and 2. are repeated for the next higher node
(parent node) in the customer hierarchy, then for the next higher and so on
up to the root
4. If ATP is not sufficient, steps 1. to 3. are repeated for all alternate products
that may substitute the original requested product (e.g. downgrading)
5. If ATP is not sufficient, steps 1. to 4. are repeated, but searched forward in
time, up to a predefined number of time buckets.
(order is made late) 39
ATP Consumption – steps 1 & 2
Order:
• 300 units
• from customer in East Germany
• requested date in week 4
40
70 50 60 10
Request
300 units
week 4
World_Wide_Sales -> Europe -> Germany -> East
weeks 1 2 3 4
1. Time
1. ATP check for customer group East Germany for week 4
2. ATP check for week 3 and for week 2
(allowed to consume ATP 2 weeks backwards in time)
ATP found:
10 in week 4, 60 in week 3, 50 in week 2 = 120 in total
ATP Consumption – step 3
41
West East
Germany
Request
300 units
week 4
weeks
weeks weeks
1 2 3 4
1 2 3 4 1 2 3 4
20 10 30 80
30 20 40 30 70 50 60 10
2. Customer
3. ATP check in next higher customer node Germany
(but no ATP in Europe or World-Wide is available)
ATP found
80 in week 4, 30 in week 3, 10 in week 2 = 120 in total
ATP Consumption – step 4
4. ATP search for alternate products
(alternates are sorted by priority)
• alternate with highest priority is considered first and the same steps are
applied as for the original product
(first search back in time and second search up the customer hierarchy)
• same steps to the alternate with second priority and so on
42
East
East
East East, Product A
East, Product A, alternate 1
East, Product A, alternate 2
East, Product A, alternate 3
Request
300 units
week 4
70 50 60 10
1 2 3 4 weeks
3. Product
Contents/Objectives
One of the key criteria to evaluate order fulfillment systems is their capability to
handle temporary stock-out situations
If a company is facing a temporary stock-out situation, it will want to minimize the
overall (i.e. short and long term) negative consequences
In this session we will analyze, which negative consequences result from stock-
out situations and how they can be mitigated through the use of order fulfillment
systems
A case study from the pharmaceuticals industry will give you insight into specific
problems regarding the management of stock-out situations and will facility a
discussion about suitable models and techniques for handling these situations
effectively
44
Impact of Order Fulfillment on Profitability
Order promising is trivial if we always have enough capacity/inventory
available to fulfill customer’s requirements!
But,
• we want systems to be tight (i.e. minimize excess inventory, maximize capacity
utilization)
• we have to cope with uncertainties (supply, manufacturing, demand)
How can we handle situations in which not all customer requirements
(quantity and delivery date) can be fulfilled?
45
Impact of Order Fulfillment on Profitability
If inventory/capacity is not sufficient for fulfilling all customer requirements:
• Allocation of available inventory/capacity to incoming customer orders
• More appropriate: allocation of stock-outs to customer orders
Allocation has impact on short and long term profitability:
46
Short term: Lost sales, penalties, additional cost for expediting or upgrading
Immediate impact on profitability
Long term: Customer satisfaction, loss of goodwill, (loss of reputation)
Impact on Customer Lifetime Value, i.e. on long term
profitability
Possible trade-off
Traditional Inventory Theory
Stocking decisions based on:
• Demand forecasts/probability distribution of (anonymous) demand
• Based on aggregate data (e.g. demand in cycle time)
Suggests: Determine inventory policy that minimizes
47
holding cost + fixed set-up/ordering cost + penalty cost
holding cost + fixed set-up/ordering cost
subject to: (/) service level constraint
Implemented!
Determines potential for order fulfillment
Traditional Inventory Theory vs.
Order Fulfillment
Inventory Management Order Fulfillment
SC Planning SC Execution
Based on Forecasts/aggregate anonymous
demand
Based on detailed order information
Stochastic Deterministic
Demand fill rate (represented ex ante
through /-service level)
Order fill rate based on required due dates
and quantities
Penalizes unfilled fraction of aggregate
demand
Penalty should depend on customer
(order)
48
Order fulfillment is especially concerned about temporary stock-outs, i.e.
• materialization of 1-/1-
• situations where aggregate but not disaggregate demand can be fulfilled
• situations caused by SC disruptions (supply shortages, yield problems, …)
Impact of Order Fulfillment on Profitability
49
Temporary stock-outs – ways to
make our customers unhappy
Different short and
long term consequences
(highly customer specific!)
• Reject order
• Quote unrealistic delivery date
• Quote late delivery date
• Quote less than ordered quantity
• Partial deliveries (first delivery meets
delivery date requirements)
• Partial deliveries (first delivery late)
Better, but not necessarily
feasible/available to all customers
Different impact on
fulfillment cost
Has to be decided for every individual order!
• Meet customer requirements with
remaining capacity/inventory
• Upgrade
• Expedite
•…
Impact of Order Fulfillment on Profitability
What are the long term consequences of not meeting a customer’s requirements in regard to a specific order?
Customer’s reaction:
• No reaction ( CLV= CLVb - CLVa = 0)
• Chooses different supplier ( CLV = CLVb)
• Chooses different supplier, may return after a while ( CLV > 0)
• Procures portion of products from different suppliers ( CLV > 0)
Customer’s reaction depends on:
• Availability of alternative suppliers (not order specific)
• Contractual relationship (not order specific)
• Utility/need/criticality of order (i.e. impact on customer side)
• Deviation from customer’s requirements (tardiness)
• Fulfillment history
50
Objective of Order Fulfillment in
Stock-out Situations
In a temporary stock-out situation, order fulfillment should allocate
available inventory/capacity to customer orders in such a way,
that the overall negative impact is minimized
Take into account impact of individual orders and importance of customer’s
(represented by CLV)
Exploit all options (e.g. partial deliveries, upgrades, expediting) if economically
feasible (i.e. additional cost less than negative consequences CLV)
51
Case Data
General information:
• Pharmaceuticals company, operating mainly in Europe, 1000 employees, € 378 M revenue in 2003/2004
• Products: Variety of prescription and over the counter drugs
• Relevant products for case: over the counter pharmaceuticals (e.g. cough drops, herbal laxatives, vitamins)
Production process:
• Large batch production, make to stock
• Procurement of ingredients mainly from local suppliers
• Quality control (batch) with uncertain outcome, 2-3 days
Distribution:
• Company supplies large and medium retailers, drugstore chains, individual chemists
• For German market, all products are stored at the production facility
• Shipping is outsourced
• Due to (increasing) demand variance, supply shortages and uncertain manufacturing yields, company increasingly experiences stock-outs
52
Case Data
Customer specific contracts and conditions:
• When negotiating contracts with large customers (large retailers and large drugstore
chains), company has little bargaining power
• Virtually all requirements have to be met, sometimes drastic penalties or consequences
if orders are not fulfilled according to requirements, examples:
• Complete shipments are being sent back
• penalty = sales volume of order
• price discounts enforced in next round of negotiations
• Large customers can order whatever and whenever they want and can specify delivery
date
53
Case Data
Order processing:
• Orders received through multiple channels (phone, fax, E-mail), now also online portal
• Most orders are printed and entered manually in SAP system
• Orders processed first come first served, some orders expedited, if very short delivery
lead-time
• Availability is being checked in SAP system, customer receives confirmation after order
has been processed
• No “booking levels”, only certain quantity is reserved for one “very nasty” customer
54
Case Data
One specific stock-out situation:
• October/November 2002
• Product: Cough drops
• Reason for stock-out: supply shortage (quality issues of one supplier) in combination
with high demand due to wave of flu
• Upcoming stock-out situation could have been anticipated one week prior, but no active
management of remaining inventory
• At 10/23, 150 orders (4071 units) committed with delivery dates
• Between 10/23 and 11/11 656 orders (8660 units) received
55
Case Data
56
0
200
400
600
800
1000
1200
1400
1600
1800
23
-10
24
-10
25
-10
28
-10
29
-10
30
-10
31
-10
1-1
1
4-1
1
5-1
1
6-1
1
7-1
1
8-1
1
11
-11
12
-11
13
-11
14
-11
15
-11
18
-11
19
-11
Ordered QuantityQuantity Committed Previously
Units
Dates
Inventory and Fulfillment Situation –
Company’s Results
57
-2000
-1000
0
1000
2000
3000
4000
5000
6000
7000
8000
23
-10
24
-10
25
-10
28
-10
29
-10
30
-10
31
-10
1-1
1
4-1
1
5-1
1
6-1
1
7-1
1
8-1
1
11
-11
12
-11
13
-11
14
-11
15
-11
18
-11
19
-11
Dates
Un
its
Planned Receipts Total Quantity Ordered Available Quantity
Rejected Orders – Company’s Results
58
Is this the profile we want?
0
100
200
300
400
500
1 2 3 4 5
Customer Priority
Total number of orders Rejected
Alternatives
SAP’s methodology:
• Availability is checked through ATP-function in SAP
• For main customers, future orders are forecasted
• If forecasted orders exceed available quantity, certain incoming orders are blocked
(rejected?)
• Only orders from high priority customers can be processed
What are advantages/disadvantages of this approach?
59
Alternatives
-2000
-1000
0
1000
2000
3000
4000
5000
6000
7000
8000
23
-10
24
-10
25
-10
28
-10
29
-10
30
-10
31
-10
1-1
1
4-1
1
5-1
1
6-1
1
7-1
1
8-1
1
11
-11
12
-11
13
-11
14
-11
15
-11
18
-11
19
-11
Dates
Un
its
Planned Receipts Total Quantity Ordered Available Quantity
60
Similar: Booking levels
• Reserve portions of available inventory for certain customer classes
• Dynamic service level approach – how do we determine quantities to be reserved?
• What are the prerequisites?
What are the advantages/disadvantages of a booking level approach?
A Different Approach:
Batching and Partial Deliveries
Apply batching and partial deliveries: Utilize customers’ flexibility in terms of
• response time and
• delivery quantities
Customers do not require same day order confirmation
Some customers are willing to accept partial deliveries
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Experiment 1: 1-Day-Batching,
Partial Deliveries Allowed
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Partial deliveries: 1.22 %
Not very exciting! What are the reasons? What are the
implications?
0
10
20
30
40
50
60
70
1 2 3 4 5 Overall
Customer Priority
Company's results Model's results
Unfille
d o
rders
in %
Experiment 2: 1-Day-Batching,
Partial Deliveries Enforced
Partial deliveries are enforced: If customer generally agrees to partial deliveries,
all orders will be fulfilled with two deliveries if possible (see model assumptions
and constraints)
Impact on available inventory:
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-2000
-1000
0
1000
2000
3000
4000
5000
6000
7000
8000
23
-10
24
-10
25
-10
28
-10
29
-10
30
-10
31
-10
1-1
1
4-1
1
5-1
1
6-1
1
7-1
1
8-1
1
11
-11
12
-11
13
-11
14
-11
15
-11
18
-11
19
-11
Dates
Un
its
Planned Receipts Committed and Unfulfilled Quantity Available Quantity Partial Delivery Quantities
Experiment 2: 1-Day-Batching,
Partial Deliveries Enforced
Results: Unfilled orders
Partial deliveries:
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0
10
20
30
40
50
60
70
1 2 3 4 5 Overall
Customer Priority
Company's resultsResults Experiment 1Results Experiment 2
Customer Priority 1 2 3 4 5 Overall
Partial Deliveries in % 0,00 3,96 0,00 9,52 48,28 7,62
Further Analysis
Impact of batching: Two and three day intervals • Accepted by customers? Is the achieved benefit worth it?
• Problem: Some orders have to be fulfilled next day. How do we handle these?
How strong is the impact of partial deliveries? • Does it make sense to try to negotiate partial deliveries with customers?
• Do we want to compensate them for accepting these?
Are there any other ways of creating flexibility in terms of customers’ requirements which can be utilized in stock-out situations?
Are there more intelligent ways of allocating the available inventory to customers?
To which extent do these results apply to other stock-out situations? Can they be generalized?
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Readings
• Pibernik, R. (2005). Advanced available-to-promise: Classification,
selected methods and requirements for operations and inventory
management. International Journal of Production Economics, 93-94(1),
239-252.
• Kilger, C./Meyr, R. (2010). Demand Fulfilment and ATP, in: Stadtler,
H./Kilger, C. (eds.): Supply Chain Management and Advanced Planning,
Berlin & Heidelberg, Chapter 9.
• Pibernik, R. (2006). Managing stock-outs effectively with order fulfillment
systems. Journal of Manufacturing Technology Management, 17(6), 721-
736.
(Note: This article provides the details of the case study presented on
slides 52-65; you are not required to study the formal details)
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