METHOD AND A SYSTEM FOR CUSTOMER DEMAND DRIVEN SUPPLY CHAIN PLANNING

Abstract

The invention relates to a computer-implemented MRP method for controlling materials in a supply chain (SC) with customer segments (CS1, CS2). The invention is advantageous in that there is calculated a safety stock curve (SSC) in a time-phased manner (m, n) to cover an uncertainty until a demand is fulfilled based on customer data (CD) and material data (MD). The time until demand is fulfilled is a demand fulfilment time (DFT), the safety stock curve (SSC) being calculated as a function of this demand fulfilment time (DFT) in order to meet specified target service level (TSL1, TSL2) and simultaneously minimize inventory levels in said plurality of distribution centres (M_DC, DC2). The invention provides advances in MRP with respect to an optimum with demand compliance to required service levels while not unnecessarily increasing safety stock levels. Simulations convincingly demonstrate the effects of the invention.

Claims

1. A computer-implemented method for controlling materials in a supply chain, the method comprising: receiving customer data related to a plurality of customer segments and a corresponding demand from each customer segment, wherein each customer segment includes a specified target service level; receiving material data related to a plurality of distribution centres corresponding to an amount of materials on stock in each distribution centre of the plurality of distribution centres, wherein at least one distribution centre comprises a main distribution centre supplying one or more other distribution centres of the plurality of distribution centres; calculating, based on the customer data and the material data, a safety stock curve in a time-phased manner to cover an uncertainty until a demand is fulfilled based on the customer data and the material data, wherein the time until demand is fulfilled is defined as a demand fulfilment time, and wherein the safety stock curve is calculated as a function of the demand fulfilment time in order to meet the specified target service level for each customer segment and to minimize inventory levels in the plurality of distribution centres; and outputting orders to the plurality of distribution centres in due time based on the safety stock curve.

2. The method according to claim 1, wherein the safety stock curve is calculated as a function of the demand fulfilment time across the supply chain.

3. The method according to claim 1, wherein the safety stock curve is calculated as a function of the demand fulfilment time across the supply chain from one or more customers segments of the plurality of customer segments of the main distribution centre.

4. The method according to claim 1, wherein one or more customer segments of the plurality of customer segments includes independent demands.

5. The method according to claim 1, wherein the safety stock curve is calculated independent of a specific lead time.

6. The method according to claim 1, wherein the order is initiated when a projected stock of material in one or more distribution centres of the plurality of distribution centres is below the safety stock curve.

7. The method according to claim 1, wherein the calculation of the safety stock curve depends on whether the demand can be modelled as a continuous demand.

8. The method according to claim 7, wherein the demand is modelled based on a normal distribution or Gamma distribution.

9. The method according to claim 1, wherein the calculation of the safety stock curve depends on whether the demand can be modelled as a discrete demand.

10. The method according to claim 9, wherein the demand is modelled based on Compound Poisson distribution.

11. The method according to claim 1, wherein the safety stock curve comprises a reorder point curve.

12. The method according to claim 1, further comprising: calculating a buffer curve for the supply chain, the buffer curve being calculated so that replenishment orders are fixed in time and/or quantity, if a projected stock is positioned between the safety stock curve and the buffer curve.

13. The method according to claim 1, further comprising: calculating a negative safety stock value for one or more upstream stock points to reduce total safety stock by utilizing a portfolio effect of the downstream demand variation sources.

14. The method according to claim 13, wherein the safety stock in the supply chain increases across possible stock points for storing material until a decoupling stock point independent of a negative safety stock is reached.

15. The method according to claim 1, wherein the order released to a production, supplier or transportation entity when supply constraints exist at the plurality of distribution centres.

16. The method according to claim 1, wherein executing the order comprises transporting, manufacturing, assembling, or purchasing corresponding materials in the supply chain, or a combination thereof.

17. The method according to claim 1, further comprising: receiving, by a machine learning engine, a plurality of datasets comprising a plurality of customer data and a plurality of material data; training, by the machine learning engine, a machine learning model according to the plurality of datasets, wherein the calculating the safety stock curve is output from the machine learning model.

18. The method according to claim 17, further comprising: receiving, by the machine learning engine, an additional one or more datasets comprising customer segments and material data; and retraining, by the machine learning engine, the machine learning model based on the additional one or more datasets; and adjusting the safety stock curve according to the retrained machine learning model.

19. A computer-implemented planning system for controlling materials in a supply chain on one or more computers, the system comprising: a computer configured or adapted to: receive customer data related to a plurality of customer segments and a corresponding demand from each customer segment, wherein each customer segment includes a specified target service level; receive material data related to a plurality of distribution centres corresponding to an amount of materials on stock in each distribution centre of the plurality of distribution centres, wherein at least one distribution centre comprises a main distribution centre supplying one or more other distribution centres of the plurality of distribution centres; calculate, based on the customer data and the material data, a safety stock curve in a time-phased manner to cover an uncertainty until a demand is fulfilled based on the customer data and the material data, wherein the time until demand is fulfilled is defined as a fulfilment time, and wherein the safety stock curve is calculated as a function of the demand fulfilment time in order to meet the specified target service level for each customer segment and to minimize inventory levels in the plurality of distribution centres and output orders to the plurality of distribution centres in due time based on the safety stock curve.

20. A computer program product being adapted to enable a computer system comprising at least one computer having data storage means in connection therewith to control a computer-implemented planning system according to claim 19.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0066] The invention will now be described in more detail with regard to the accompanying figures. The figures show one way of implementing the present invention and are not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

[0067] FIG. 1 is an overall schematic outline of a supply chain according to the present invention,

[0068] FIG. 2A is a generic and schematic supply chain with a MRP method according to the present invention; FIGS. 2B and 2C illustrate the problem to be solved by the present invention,

[0069] FIG. 3 schematically shows another supply chain with a MRP method according to the present invention,

[0070] FIG. 4A shows an example of how invention is better than the two prior art methods, and FIG. 4B is a table of simulation results obtain by a MRP method according to the present invention as compared to two prior art methods,

[0071] FIG. 5A schematically shows other supply chains with a MRP method according to the present invention together with corresponding safety stock curves across the supply chain, FIG. 5B shows an example of a safety stock curve, FIG. 5C shows both a safety stock curve and a buffer curve

[0072] FIGS. 6-8 schematically show other supply chains with a MRP method according to the present invention together with corresponding safety stock curves,

[0073] FIGS. 9-10 schematically show various other supply chains with a MRP method according to the present invention, and

[0074] FIG. 11 is a schematic system-chart representing an out-line of/in detail the operations of the computer-implemented method according to the invention.

DETAILED DESCRIPTION

[0075] FIG. 1 is an overall schematic outline of a supply chain SC 100. The flow of materials or goods is generally from the left towards the right in FIG. 1 as indicated by the various block arrows. In the upper most level of FIG. 1, a supply chain infrastructure is indicated in circles with suppliers SUP, sites PLANTS (incl. contract manufacturing organisations CMO), and transport between the suppliers and sites delivering the materials to the various places and sites in the supply chain.

[0076] A distribution centre will below be abbreviated DC, and DCs in plural. A main distribution centre is accordingly abbreviated MDC. In the below embodiments, just one main distribution centre is shown, but the present invention may of course be implemented with a plurality of main distributions centres in the understanding of this concept, as the skilled person in MRP will readily understand once the principle and teaching of the present invention is appreciated. Thus, one or more main distribution centre(s) may also be called primary distribution centres, whereas the other distribution centres may be called secondary distribution centres in the following.

[0077] On the very left is indicated the relevant time scales of operation, a week scale having Purchasing followed by Production scheduling and transport towards to the (planned) sites as the skilled person will readily understand.

[0078] On a longer time scale, e.g. months, the various planning steps and more strategic goals are illustrated schematically. The S&OP abbreviation means sales & operation planning.

[0079] The present invention relates to a computer-implemented MRP method for controlling materials in a supply chain SC 100. Schematically indicated in the lower right corner of FIG. 1 is a corresponding computer COMP functionally connected and integrated with a database DB for storing and retrieving various data, stored in appropriate and various data formats, related to implementing the present invention. Though indicated as a single computer COMP and a single database DB, the skilled person will readily understand that a plurality of computers and/or databases may be applied for implementing the invention, for example a plurality of geographically distributed computers, incl. handheld devices, that are interconnected for example via the internet, by wire and/or wirelessly, for example a cloud-based computer solution.

[0080] The computer COMP is arranged for receiving customer data CD related to a plurality of customer segments, e.g. high priority customers and other customers, and the corresponding demand from each customer segment, where each customer segment having a specified target service level, such as percentage of service level to be reached. The demand from each customer segment may be a predicted, a forecasted and/or a real demand as the skilled person will understand.

[0081] The computer COMP is likewise arranged for receiving material data MD related to a plurality of distribution centres often just called ‘locations’ in the field of logistics, e.g. M_DC and DC2 as shown in FIG. 2A, the data MD being related to the amount of materials on stock in each distribution centre, where at least one distribution centre is a main distribution centre M_DC supplying one, or more, other distribution centres DC2 in the supply chain SC 100. Material data includes master data describing the materials, locations, and the supply chain structure etc.

[0082] Customer data CD and material data MD may be automatically collected in the supply chain and transmitted to the computer COMP, such as by use of tracing and tracking technology applicable in a supply chain, as the skilled person will understand. These data may also be manually collected, or in any combination between being automatically and manually collected.

[0083] Based upon said customer data CD and said material data MD, the computer will output orders, preferably upstream orders and/or replenishment order RO, as schematically indicated by the arrow from the computer COMP, back to the plurality of distribution centres in the supply chain SC in due time as normally performed in MRP, but based on a new and advantageous safety stock curve according to the present invention, as it will be explained below.

[0084] FIG. 2A is a generic and schematic supply chain with a MRP method according to the present invention, where a distribution centre DC2 is distributing materials to a customer segment CS1 having an independent demand INDD and is in turn supplied from the main distribution centre M_DC thereby experiencing a dependent demand DD from the distribution centre DC2, for example between a warehouse and a retailer like the skilled person in supply chain management will readily understand. Each of the distribution centres M_DC and DC2 can of course each have a plurality of customer segments, but for illustrative purposes, the invention is initially explained in this simplified setup, the teaching and general principle of the invention, and the associated benefits, not being limited to this setup, as the skilled person in supply chain management will also readily understand.

[0085] FIG. 2B shows that an order proposal is created at DC2 when the projected stock gets below safety stock. The order proposal on DC2 has a dependent requirement on M_DC. This dependent requirement on M_DC reduces the projected stock on M_DC to below safety stock. This creates an order on M_DC because the replenishment lead time on M_DC (m weeks) is equal to the date when the project stock is below the safety stock.

[0086] FIG. 2C shows the situation x weeks later. The order proposal on DC2 has moved earlier because the sales has been greater than the forecast during the x weeks. The dependent requirement from the order proposal on DC2 is also moved earlier. This dependent requirement on M_DC is now earlier than the replenishment order on M_DC that is already in progress. There is now a high probability that there will be stock outs on M_DC.

[0087] The invention is particular in calculating a safety stock curve SSC, cf. FIGS. 5-8 for some examples, in a time phased manner based on the two periods m and n around the main distribution centre M_DC to cover an uncertain until a demand is fulfilled based both on the customer data CD and the material data MD. In the Figures and the corresponding description, the invention is illustrated with the periods m and n being measured in weeks, e.g. 6 and 2 weeks, but the invention can of course be implemented in any relevant time period for MRP, such as alternatively hours, days, months, or even years. The number of time periods may similarly be adjusted to the number of distribution centres as the skilled person will immediately understand, the embodiment with two periods in weeks merely being chosen for illustrative purposes. The time until demand is fulfilled is defined as a demand fulfilment time DFT, and the safety stock curve SSC is then calculated as a function of the demand fulfilment time DFT in order to meet said specified target service level, TSL1 and TSL2 in the distribution centres and simultaneously minimize inventory levels in said plurality of distribution centres M_DC and DC2, respectively.

[0088] As also indicated in FIG. 1, the invention is then implemented in the supply chain SC 100 by outputting, e.g. from a computer COMP, upstream orders RO to the plurality of distribution centres in said supply chain in due time based on said safety stock curve SSC with resulting advantageous and unexpected results. The safety stock curve is used to drive the supply net requirements planning and bill-of-material BOM explosion e.g., to trigger upstream orders such as manufacturing, purchase, replenishment, transportation etc. in due time with sufficient total buffers. This is based on traditional forecast driven supply planning—but using the safety stock curve. Thus, orders are created where the projected stock goes below the safety stock curve.

[0089] For further illustrating the invention, the invention is simulated and compared to two prior art methods called Method 1 and Method 2. Thus, FIG. 3 schematically shows a supply chain with a MRP method according to the present invention like in FIG. 2A with m=6 weeks and n=2 weeks. See also FIG. 4A with a table of results obtained by a MRP method according to the present invention as compared these two prior art methods and FIG. 4B for a number of simulated results.

[0090] Customer segment CS1 is served by DC2:

[0091] Average Forecast=101 units per week, average coefficient of variance CV (weekly) 29%

[0092] Customer segment CS2 served by M_DC:

[0093] Average Forecast=100 per week, average coefficient of variance CV (weekly) 30%

[0094] There is assumed an Independent demand INDD from these customer segments, cf. FIG. 2A.

[0095] Distribution centre DC2 is a secondary distribution centre with Service level TSL1=98%

[0096] Dependent demand from DC2 to M_DC: Order size=500

[0097] Distribution centre M_DC is the main distribution centre: Order size=900: Service level TSL2=98%

Prior Art Methods

[0098] There are generally two existing methods to calculate the safety stocks on DC2 and M_DC in this situation:

Method 1:

[0099] Safety stock on DC2 is only covering the replenishment time of DC2 (n weeks).

[0100] Safety stock on M_DC is then covering the replenishment time of M_DC (m weeks) for the full demand on M_DC.

[0101] The problem with this prior art method is that the order to replenishment of M_DC can be triggered too late to handle the replenishment of DC2 and the independent demand on DC2. The result may be out of stock of materials on M_DC.

Method 2:

[0102] Safety stock on DC2 covering the full replenishment time of both M_DC and DC2 (m+n weeks). Safety stock on M_DC covering the replenishment time of DC2 (m weeks) but only for the independent demand on M_DC.

[0103] The problem with this method is that the order to replenishment of DC2 can be triggered too early (too high safety stock). The result may be out of stock of materials on M_DC and higher stock on D2. The risk of stock out increases, if the higher replenishment order size to DC2 is large compared to the total demand on DC2.

The Invention

[0104] The method according to this invention instead uses a new safety stock curve SSC to calculate the safety stocks. The safety stocks are then not static over time, and surprisingly combines the benefits from both prior art Method 1 and Method 2.

[0105] The safety stock on DC2 in week m+n is the same as for Method 2.

[0106] The safety stock on DC2 in week m is the same as for Method 1.

[0107] The advantage compared to Method 1 is that the planned replenishment order to DC2 is in this way planned in due time—so that the dependent demand on M_DC is known in advance. The replenishment order to M_DC is in this way planned in due time (like in Method 2).

[0108] The advantage compared to Method 2 is accordingly that the planned replenishment order to DC2 is in this way planned in due time like Method 2—but is triggered later due to the lower safety stock on the shorter horizon. The replenishment order to M_DC is in this way not triggered too early (like in Method 1).

[0109] In the table shown in FIG. 4A, an example is simulated in great detail in weeks 0-21 with the two prior art methods, called Method 1 and Method 2 as described above, and the present invention. Some conclusions from this example follows: [0110] For Method 1, there is a stock out on the main distribution centre M_DC in week 12 and 16 because replenishment to M_DC is too late. [0111] With Method 2, there is a stock out on M_DC in week 6 and 15 because replenishment to the other distribution centre DC2 is too early. [0112] The invention with replenishment orders being calculated using the safety stock curve SSC facilitates that there are no stock outs situations in these weeks.

[0113] In FIG. 4B, there is a summarized statistic overview for a series of simulations like the one shown in FIG. 4A with the most important findings from these simulations. Overall, the invention provides average service levels SL of 99.7% and 96.5% at the secondary and main distribution centre, respectively, against a nominal target of 98% for both. Particularly at the main distribution centre in the Table) this is significantly better than the prior art methods, Method 1 and Method 2, with corresponding service levels of only 92.1% and 91.1%, respectively. Thus, the invention is superior to the Method 1 and Method 2 known in the prior art for supply chain management and inventory control.

[0114] FIG. 5A schematically shows another supply chain SC 100 with a MRP method according to the present invention with a corresponding safety stock curve SSC (lower graph) across the supply chain SC 100. One customer segment CS1 can be categorized as high priority, and the other segment CS2 as normal or lower priority. The main distribution centre M_DC can be defined per product, and likewise with the distribution centre DC2. In this embodiment, with Assembly Ready Components (ARC) the components and raw materials comes from suppliers, and the components may be stocked at the supplier as indicated schematically. The end-to-end E2E supply chain planning according to the present invention enables that orders are triggered upstream based on the forecast and the time-phased safety stocks for: [0115] Transportation/replenishment order proposal [0116] Assembly To Stock (ATS) production order proposal [0117] Production order proposal [0118] Purchase order proposal

[0119] In FIG. 5B, the actual safety stock curve SSC is inserted in the lower graph for illustrating how the invention may be implemented for this specific example. In FIG. 5C, the same graph as in FIG. 5B is shown with the safety stock curve SSC together with a buffer curve BC for stabilizing the MRP calculations or simulations according to the present invention.

[0120] The safety stock curve can be calculated by using the fill rate method if the demand is continuous and may be modelled by using a Normal distribution.

[0121] The fill rate model may be used to calculate the safety stock curve:

[0122] The safety stock (ss) can be set equal to a safety factor (k) times the compound standard deviation of demand during demand fulfilment time (σ.sub.dDFT):

[0123] where

SS=k*σ.sub.dLT

and

σ.sub.dLT=√{square root over ((σ.sub.d.sup.2*DFT+d.sup.2*σ.sub.LT.sup.2))}

and where the safety factor (k) is found via the fill rate model.

[0124] Select k, where

[00004]$G\left(k\right)-G\left(k+\frac{Q}{{\sigma }_{\mathrm{dLT}}}\right)=\left(1-\mathrm{Fill}\mathrm{rate}\right)*\frac{Q}{{\sigma }_{\mathrm{dLT}}}$

G(k) is a special function of the unit normal (mean 0, standard deviation 1). This function is used for finding the expected shortages per replenishment cycle needed for fill rate calculations.

Notation:

[0125] k is the safety factor based on normal distribution function.

[0126] σ.sub.dLT is the standard deviation of demand during demand fulfilment time.

[0127] Q is the average replenishment order size.

[0128] d is the average demand per time period.

[0129] DFT is the demand fulfilment time used as the x-axis in the safety stock curve

[0130] σ.sub.d.sup.2 is the variance of demand per time period.

[0131] σ.sub.LT.sup.2 is the variance of demand fulfilment time

[0132] d.sub.dLT is the demand during demand fulfilment time

[0133] FIGS. 6-8 schematically show other supply chains with a MRP method according to the present invention together with corresponding safety stock curves.

[0134] FIG. 6 is similar to FIG. 5, but with production closer to the customer segments to the far right. This is a so-called assembly-to-order, make-to-order, engineer-to-order setup with similar advantages.

[0135] FIG. 7 is similar to FIGS. 5 and 6, but with an example of a so-called decoupling stock point. There is a direct delivery of materials from main distribution centre M_DC to customer segment CS1. Again, the main distribution centre may be defined per product, and the supply chain has assembled ready components (ARC).

[0136] FIG. 8 is similar to FIG. 7, but with an example of a so-called partly decoupling stock point. It is different from FIG. 7 in that the distribution centre DC1 has a longer lead time and higher replenishment order size as compared to DC2 and DC3. Determining partly decoupling stock point at the main distribution centre M_DC may then be performed in the following steps:

[0137] a) The replenishment order sizes to the secondary distribution centres DC2 and DC3 are not significant—due to the replenishment frequency and/or significant lower demand to these secondary DCs.

[0138] b) The high replenishment order size from DC1 will create significantly higher demand variation on the main distribution centre—and thereby higher safety stock on M_DC.

[0139] c) Modelling the expected demand from this special distribution centre DC1 depends on the demand pattern here. It is therefore better to separate this demand from DC1.

[0140] As indicated in FIG. 8, the invention therefore comprises calculating a dedicated safety stock curve SSC' to this particular situation with a longer lead time and higher replenishment order size with respect to M_DC. For the main distribution centre itself another safety stack curve SSC may be calculated and applied to order replenishment orders, as schematically in the graph below the supply chain.

[0141] FIGS. 9-10 schematically shows other supply chains SC 100 with a MRP method according to the present invention.

[0142] FIG. 9 shows a supply chain with a high priority customer segment CS1 (supply chain indicated with a dashed line) and a lower priority customer segment CS2, both segments being positioned in two different geographical locations as indicated. Each geographical location has a corresponding distribution centre named DC1 and DC2 supplied by main distribution centre M_DC. The supply chain contains Assembly ready components (ARC), components and raw materials from suppliers and components at suppliers as indicated in FIG. 9.

[0143] Throughout the supply chain i.e. end-to-end E2E there is a demand transparency: [0144] a) The demand from both the segments CS1 and CS2 are transparent through the full upstream supply chain [0145] b) The E2E demand and priority transparency upstream is used when there are constraints in material, capacity etc. or disruptions in the execution e.g. delays in production, transportation etc. [0146] c) The usage of materials, capacity etc. is prioritised according to the rules defined on segment priorities—this includes adjusting order quantities to match available capacity, materials etc.

[0147] FIG. 10 is similar to FIG. 9, and schematically indicated how stocks can be segregated automatically to use demand segment priorities. Hence, there may be automatic stock segregation so as to respect demand segment priorities: [0148] a) Stocks are automatically segregated into the demand segments in case of constraints or disturbances in the supply chain [0149] b) Rules determine which orders (production, transportation, customer orders etc.) that can allocate the stock. This is based on the different demand segments that the order covers. [0150] c) This also includes adjusting order quantities to match available capacity, materials etc.

[0151] FIG. 11 is a schematic system-chart representing an out-line of/in detail the operations of the computer-implemented method according to the invention. Thus, a computer-implemented MRP method for controlling materials in a supply chain SC 100 as illustrated in FIG. 1, the method comprising the steps of: [0152] S1 receiving customer data CD related to a plurality of customer segments CS1, CS2 and the corresponding demand from each customer segment, each customer segment having a specified target service level TSL1, TSL2, as illustrated in FIGS. 1 & 2A, [0153] S2 receiving material data MD related to a plurality of distribution centres M_DC, DC2, related to the amount of materials on stock in each distribution centre, at least one distribution centre M_DC being a main distribution centre supplying one, or more, other distribution centres DC2, in the supply chain, as illustrated in FIGS. 1 & 2A, [0154] S3 calculating a safety stock curve SSC in a time-phased manner m, n to cover an uncertainty until a demand is fulfilled based on said customer data CD and said material data MD, the time until demand is fulfilled is defined as a demand fulfilment time DFT, the safety stock curve SSC thereby being calculated as a function of said demand fulfilment time DFT in order to meet said specified target service level TSL1, TSL2 and simultaneously minimize inventory levels in said plurality of distribution centres M_DC, DC2, DC3, and/or DC4, as illustrated in FIGS. 5-10, and [0155] S4 outputting orders RO, as illustrated in FIG. 1, to the plurality of distribution centres M_DC, DC2, DC3, and/or DC4 in said supply chain in due time based on said safety stock curve SSC.

[0156] In some cases, a machine learning engine can be utilized to generate the safety stock curve. As used herein, the machine learning engine can include computer-executable software, firmware, hardware, or various combinations thereof. For example, the classification system can include a reference to the processor and a supporting data store. Further, the machine learning engine can be implemented on multiple devices or other components, local or remote to one another. The machine learning engine can be implemented in a centralized system or as a distributed system in other scalability aspects. Moreover, any reference to software can include a non-transitory computer readable medium that when executed on a computer causes the computer to perform a series of steps.

[0157] The machine learning engine described herein can include data storage, such as network accessible storage, local storage, remote storage, or a combination thereof. Data storage may utilize redundant arrays of inexpensive disks (“RAID”), tapes, disks, storage area networks (“SAN”), internet small computer system interface (“iSCSI”) SAN, fibre channel SAN, common internet archive system (“CIFS”), network attached storage (“NAS”), network file system (“NFS”), or other computer accessible storage. In one or more embodiments, the data store can be a database, such as an Oracle database, a Microsoft (Microsoft) SQL Server database, a DB2 database, a MySQL database, a seebecs (Sybase) database, an object-oriented database, a hierarchical database, or other database. The data store can utilize a flat file structure to store data.

[0158] In a first step, a predetermined data set is described using a classifier. This is the “learning step” and is done on the “training” data.

[0159] A computer implemented data store can reflect a plurality of customer segments and material data for a plurality of supply chains. The format of the stored data can be a flat file, a database, a table, or any other retrievable data storage format known in the art. In some cases, the test data is stored as a plurality of vectors, each quantity corresponding to a supply chain, each quantity comprising a plurality of customer segments for a plurality of material data and a classification regarding a safety stock. The training database can be linked to a network, such as the internet, so that its contents can be remotely retrieved by an authorized entity (e.g., a human user or a computer program). Alternatively, the training database can be located in a network-isolated computer.

[0160] Several methods for classification are known in the art, including the use of classifiers such as support vector machines, AdaBoost, decision trees, Bayesian classifiers, Bayesian belief networks (Bayesian belief networks), k-nearest neighbor classifiers, case-based reasoning, penalized logistic regression, neural nets, random forests or any combination thereof. Any classifier or combination of classifiers can be used in the classification system, as described herein.

[0161] The trained model can then be utilized (e.g., via the machine learning engine) for the calculation of a safety stock curve for a particular supply chain. The trained model can receive as input customer data and material data for a given supply chain. The trained model can, based on the classifications (e.g., various parameters and weights provided to the supply chain inputs), generate a safety stock curve for the supply chain. The safety stock curve generated can thus be based on the received data corresponding to the particular supply chain, but also based on the classifications provided the training data of the trained machine learning model.

[0162] Further, in some cases the safety stock curve can be adjusted based on a retraining of the trained model. For example, the trained model can receive as additional input, additional customer segment data and material data for supply chains. The trained model can update its classifications (e.g., adjust weights provided to input) based on the additional input data. The trained model can then, as output, as either generate a new safety stock curve for the particular supply chain, or adjust the previous safety stock curve for the supply chain.

[0163] In short, the invention relates to a computer-implemented MRP method for controlling materials in a supply chain SC with customer segments CS1, CS2 as schematically shown in FIGS. 1 and 2A. The invention is advantageous in that there is calculated a safety stock curve SSC in a time-phased manner m, n to cover an uncertainty until a demand is fulfilled based on customer data CD and material data MD. The time until demand is fulfilled is a demand fulfilment time DFT, the safety stock curve SSC being calculated as a function of this demand fulfilment time DFT in order to meet specified target service level TSL1, TSL2 and simultaneously minimize inventory levels in said plurality of distribution centres M_DC, DC2, as shown in FIGS. 5-8. The invention provides advances in MRP with respect to an optimum with demand compliance to required service levels while not unnecessarily increasing safety stock levels. Simulations convincingly demonstrate the effects of the invention, cf. FIGS. 4A and 4B.

[0164] The invention can be implemented by means of hardware, software, firmware or any combination of these. The invention or some of the features thereof can also be implemented as software running on one or more data processors and/or digital signal processors.

[0165] The individual elements of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way such as in a single unit, in a plurality of units or as part of separate functional units. The invention may be implemented in a single unit, or be both physically and functionally distributed between different units and processors.

[0166] Although the present invention has been described in connection with the specified embodiments, it should not be construed as being in any way limited to the presented examples. The scope of the present invention is to be interpreted in the light of the accompanying claim set. In the context of the claims, the terms “comprising” or “comprises” do not exclude other possible elements or steps. Also, the mentioning of references such as “a” or “an” etc. should not be construed as excluding a plurality. The use of reference signs in the claims with respect to elements indicated in the figures shall also not be construed as limiting the scope of the invention. Furthermore, individual features mentioned in different claims, may possibly be advantageously combined, and the mentioning of these features in different claims does not exclude that a combination of features is not possible and advantageous.