U.S. patent application number 15/940615 was filed with the patent office on 2018-08-02 for generating an ordering of workflow items given a partial ordering and extension data.
The applicant listed for this patent is JDA Software Group, Inc.. Invention is credited to Lori W. Debetaz, Garr S. Lystad.
Application Number | 20180218298 15/940615 |
Document ID | / |
Family ID | 61711498 |
Filed Date | 2018-08-02 |
United States Patent
Application |
20180218298 |
Kind Code |
A1 |
Lystad; Garr S. ; et
al. |
August 2, 2018 |
Generating An Ordering Of Workflow Items Given A Partial Ordering
And Extension Data
Abstract
A method of processing items associated with a workflow includes
accessing information that specifies, for each item to be
processed, each of one or more primary input items required under
normal conditions to produce the item. The method also includes
accessing information that specifies, for at least one primary
input item, an alternative input item that may replace the primary
input item under alternative conditions in producing the item to be
processed. The items to be processed are ordered such that: (a)
each item to be processed that has one or more primary input items
is placed ahead of its primary input items; and (b) each primary
input item that has one or more alternative input items is placed
ahead of its alternative input items provided doing so is not
inconsistent with the ordering according to condition (a) and is
also not inconsistent with the ordering according to condition
(b).
Inventors: |
Lystad; Garr S.; (Denton,
TX) ; Debetaz; Lori W.; (Plano, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JDA Software Group, Inc. |
Scottsdale |
AZ |
US |
|
|
Family ID: |
61711498 |
Appl. No.: |
15/940615 |
Filed: |
March 29, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09956439 |
Sep 18, 2001 |
9934478 |
|
|
15940615 |
|
|
|
|
60234862 |
Sep 22, 2000 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06Q 10/0633
20130101 |
International
Class: |
G06Q 10/06 20060101
G06Q010/06 |
Claims
1. A method of processing items associated with a workflow,
comprising: accessing by a computer, partial ordering data that
specifies, for each item to be processed, one or more primary input
items that is required under normal conditions to produce the item
to be processed; accessing by the computer, extension data
comprising one or more alternative input items to replace the one
or more primary input items when there is insufficient quantity of
the one or more primary input items to meet a demand in producing
the item to be processed, the extension data specifies one or more
extensions to the partial ordering data; generating by the
computer, an ordering of the items to be processed such that: (a)
each item to be processed that has one or more primary input items
is placed ahead of its primary input items; and (b) each primary
input item that has one or more alternative input items is placed
ahead of its alternative input items provided doing so is not
inconsistent with the ordering of items ordered according to
condition (a); and processing by the computer, the ordered items
according to the ordering.
2. The method of claim 1, wherein processing an ordered item
comprises determining a workflow value for the item.
3. The method of claim 1, wherein the items comprise tangible items
associated with a manufacturing process, processing an ordered item
comprises determining a demand value for the item, and processing
an ordered items according to the ordering.
4. The method of claim 1, wherein the extension data further
specifies which input items are primary input items to the item
they produce.
5. The method of claim 1, further comprising: generating by the
computer, a first list for each item to be processed, the first
list for each item comprising all items that are expected to be
produced using each item, whether directly or indirectly, under
normal conditions according to the partial ordering data; and
generating by the computer, a second list for each item to be
processed, the second list for each item comprising all items to be
produced using each item, whether directly or indirectly, when
there is insufficient quantity of the one or more primary input
items to meet the demand in producing the item to be processed
according to the extension data.
6. The method of claim 5, further comprising: for each item to be
processed, determining by the computer, the number of items
contained in the corresponding first list; for each item to be
processed, determining by the computer, the number of items
contained in the corresponding second list; for each item to be
processed, summing by the computer, the numbers of items contained
in the corresponding first and second lists; and in ordering the
items, sorting by the computer, the items to be processed such that
each item is placed ahead of any items having higher sums.
7. A system of processing items associated with a workflow, the
system comprising one or more computers each comprising a memory
and a processor, the one or more computers is configured to: access
partial ordering data that specifies, for each item to be
processed, one or more primary input items that is required under
normal conditions to produce the item to be processed; access
extension data comprising one or more alternative input items to
replace the one or more primary input items when there is
insufficient quantity of the one or more primary input items to
meet a demand in producing the item to be processed, the extension
data specifies one or more extensions to the partial ordering data;
generate an ordering of the items to be processed such that: (a)
each item to be processed that has one or more primary input items
is placed ahead of its primary input items; and (b) each primary
input item that has one or more alternative input items is placed
ahead of its alternative input items provided doing so is not
inconsistent with the ordering of items ordered according to
condition (a); and process the ordered items according to the
ordering.
8. The system of claim 7, wherein processing an ordered item
comprises determining a workflow value for the item.
9. The system of claim 7, wherein the items comprise tangible items
associated with a manufacturing process and processing an ordered
item comprises determining a demand value for the item.
10. The system of claim 7, wherein the extension data further
specifies which input items are primary input items to the item
they produce.
11. The system of claim 7, wherein the one or more computers is
further configured to: generate a first list for each item to be
processed, the first list for each item comprising all items that
are expected to be produced using each item, whether directly or
indirectly, under normal conditions according to the partial
ordering data; and generate a second list for each item to be
processed, the second list for each item comprising all items that
would be expected to be produced using each item, whether directly
or indirectly, when there is insufficient quantity of the one or
more primary input items to meet the demand in producing the item
to be processed according to the extension data.
12. The system of claim 11, wherein the one or more computers is
further configured to: for each item to be processed, determine the
number of items contained in the corresponding first list; for each
item to be processed, determine the number of items contained in
the corresponding second list; for each item to be processed, sum
the numbers of items contained in the corresponding first and
second lists; and in ordering the items, sort the items to be
processed such that each item is placed ahead of any items having
higher sums.
13. A non-transitory computer-readable media embodied with software
that processes items associated with a workflow, the software when
executed by one or more computers is configured to: access partial
ordering data that specifies, for each item to be processed, one or
more primary input items that is required under normal conditions
to produce the item to be processed; access extension data
comprising one or more alternative input items to replace the one
or more primary input items when there is insufficient quantity of
the one or more primary input items to meet a demand in producing
the item to be processed, the extension data specifies one or more
extensions to the partial ordering data; generate an ordering of
the items to be processed such that: (a) each item to be processed
that has one or more primary input items is placed ahead of its
primary input items; and (b) each primary input item that has one
or more alternative input items is placed ahead of its alternative
input items provided doing so is not inconsistent with the ordering
of items ordered according to condition (a); and process the
ordered items according to the ordering.
14. The non-transitory computer-readable media of claim 13, wherein
processing an ordered item comprises determining a workflow value
for the item.
15. The non-transitory computer-readable media of claim 13, wherein
the items comprise tangible items associated with a manufacturing
process and processing an ordered item comprises determining a
demand value for the item.
16. The non-transitory computer-readable media of claim 13, wherein
the extension data further specifies which input items are primary
input items to the item they produce.
17. The non-transitory computer-readable media of claim 13, further
configured to: generate a first list for each item to be processed,
the first list for each item comprising all items that are expected
to be produced using each item, whether directly or indirectly,
under normal conditions according to the partial ordering data; and
generate a second list for each item to be processed, the second
list for each item comprising all items that would be expected to
be produced using each item, whether directly or indirectly, when
there is insufficient quantity of the one or more primary input
items to meet the demand in producing the item to be processed
according to the extension data.
18. The non-transitory computer-readable media of claim 13, further
configured to: for each item to be processed, determine the number
of items contained in the corresponding first list; for each item
to be processed, determine the number of items contained in the
corresponding second list; for each item to be processed, sum the
numbers of items contained in the corresponding first and second
lists; and in ordering the items, sort the items to be processed
such that each item is placed ahead of any items having higher
sums.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 09/956,439, filed on Sep. 18, 2001, entitled
"GENERATING AN ORDERING OF WORKFLOW ITEMS GIVEN A PARTIAL ORDERING
AND EXTENSION DATA," which claims the benefit under 35 U.S.C.
.sctn. 119(e) to U.S. Provisional Application No. 60/234,862, filed
Sep. 22, 2000, and entitled "System and Method for Generating a
Total Ordering of Objects from a Partial Ordering with Possibly
Inconsistent Extension Data." U.S. patent application Ser. No.
09/956,439 and U.S. Provisional Application No. 60/234,862 are
assigned to the assignee of the present application. The subject
matter disclosed in U.S. patent application Ser. No. 09/956,439 and
U.S. Provisional Application No. 60/234,862 is hereby incorporated
by reference into the present disclosure as if fully set forth
herein.
TECHNICAL FIELD
[0002] This invention relates to logistics planning, and more
specifically generating a total ordering of workflow items given a
partial ordering and extension data.
BACKGROUND
[0003] Allocation of resources, which may include tangible
resources (such as raw materials, component parts, equipment, and
labor) or intangible resources (such as processing time and cost
allocation), typically poses many challenges in commercial or other
enterprises. Given the numerous ways in which available resources
may be allocated in connection with activities of an enterprise,
and the fact that resource allocation schemes may differ widely as
to their efficacy (in terms of their ability to maximize output,
profit, or other desired performance measures), complex systems for
logistics planning have been developed. Such logistics planning
systems have been advantageously used in, for example,
manufacturing a product within a factory or other manufacturing
environment. In considering a manufacturing process for an item,
for example, it may be necessary to account for the materials,
components, or other inputs that will be used in assembling,
fabricating, processing, synthesizing, or otherwise producing the
item. However, prior techniques have been suboptimal in that they
have not typically employed intelligent methods to properly order
items for consideration by an associated logistics planning
system.
SUMMARY
[0004] According to the present invention, disadvantages and
problems associated with previous logistics planning techniques are
reduced or eliminated.
[0005] In one embodiment of the present invention, a
computer-implemented method of processing items associated with a
workflow includes accessing information that specifies, for each
item to be processed, one or more primary input items that may be
required under normal conditions to produce the item to be
processed. The method also includes accessing information that
specifies, for at least one primary input item, an alternative
input item that may replace the primary input item under
alternative conditions in producing the item to be processed. The
items to be processed are ordered such that: (a) each item to be
processed that has one or more primary input items is placed ahead
of its primary input items; and (b) each primary input item that
has one or more alternative input items is placed ahead of its
alternative input items provided doing so is not inconsistent with
the ordering of items ordered according to 15 condition (a) and is
also not inconsistent with the ordering of items ordered according
to condition (b). The ordered items are processed according to the
ordering using a software component.
[0006] In another embodiment, a computer-implemented method of
processing items associated with a workflow includes accessing
information that specifies, for each of a plurality of items, one
or more primary input items that under normal conditions would be
upstream of the item within the workflow. The method also includes
accessing information that specifies, for each of one or more items
within the plurality of items, one or more alternative input items
that under alternative conditions would be upstream of the item
within the workflow instead of corresponding primary input items,
where each alternative input item corresponds to one or more
primary input items. An ordered list of the items is generated such
that: (a) each item having one or more upstream primary input items
is placed ahead of these primary input items; and (b) each primary
input item corresponding to one or more alternative input items is
placed ahead of these corresponding alternative input items
provided doing so is not inconsistent with the ordering of items
ordered according to condition (a) and is also not inconsistent
with the ordering of items ordered according to condition (b). The
items are processed according to the ordered list using a software
component.
[0007] Particular embodiments of the present invention may provide
one or more technical advantages. The present invention generates
an ordering of items, which may be a total ordering, given a
partial ordering of the items and extension data reflecting one or
more extensions to the partial ordering. For example, the present
invention may be used to sort items in a factory or other
manufacturing environment such that (1) input items used to produce
another item are placed behind that item in an ordered list of
items and, at the same time, (2) any alternates to a primary item
are placed behind the primary item in the ordered list where
possible. Since the second criterion may contradict the first
criterion in some cases, and may contradict itself in some cases,
providing an efficient technique that uses the second criterion for
the sort only when it is appropriate to do so may provide an
important technical advantage in certain embodiments. In a
particular embodiment in which items are associated with a
manufacturing process, the generated ordering of items may be used
in determining a total demand for an item considering demands for
all other items to which the item is a direct or indirect input,
which may allow for more efficient resource allocation, planning,
scheduling, or other appropriate tasks. The present invention may
allow a planning, scheduling, or other logistics system to loop
through a list of all relevant items such that an item is
considered before any of its input items and, to the extent
possible consistent with this goal, such that a primary item is
considered before one or more alternates of the primary item. One
or more other technical advantages may be apparent to those skilled
in the art from the figures, descriptions, and claims included
herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] To provide a more complete understanding of the present
invention and the features and advantages thereof, references is
made to the following description taken in conjunction with the
accompanying drawings, in which:
[0009] FIG. 1 illustrates an example process for generating an
ordering of items given a partial ordering and extension data;
and
[0010] FIG. 2 illustrates an example initialization phase portion
of an example process for generating an ordering of items given a
partial ordering and extension data;
[0011] FIG. 3 illustrates an example downstream transitive closure
phase portion of an example process for generating an ordering of
items given a partial ordering and extension data;
[0012] FIG. 4 illustrates an example downstream transitive closure
sub-process;
[0013] FIG. 5 illustrates an example extension phase portion of an
example process for generating an ordering of items given a partial
ordering and extension data; and
[0014] FIG. 6 illustrates an example sort phase portion of an
example process for generating an ordering of items given a partial
ordering and extension data.
DETAILED DESCRIPTION
[0015] In manufacturing environments, it may be desirable to reduce
the complexity and number of calculations involved in determining
demand or other values for items associated with a manufacturing
process. Such items might include raw materials, component parts,
assemblies, finished products, or any other suitable items. While
items are primarily described as being physical things, or
representations of physical things in a computer data structure,
the present invention contemplates items being any appropriate
tangible or intangible things, such as mere items of information.
In some manufacturing environments, such as those involving lot
sizing, consolidation, usage of primary versus alternate items, or
other constraints, calculations are often simplified if the total
demand or other value of interest for a particular item is known
before attempting to determine how and in what quantities the
particular item will be produced. To this end, it may be desirable
to know the complete set of demands or other values of interest for
all other items directly or indirectly produced using the
particular item before planning the manufacture of the particular
item. Intelligently ordering items for consideration by a suitable
planning, scheduling, or other logistics system may help accomplish
this goal. Those skilled in the art will appreciate that, although
ordering of items in a manufacturing environment is primarily
described, particularly for purposes of demand planning, the
present invention encompasses the ordering or any suitable workflow
items for any appropriate purpose. The present invention may be
implemented in a system incorporating one or more processors,
memory, and other resources associated with one or more
computers.
[0016] As discussed above, computing efficiency may be enhanced
where the total demand for an item is known before computation is
attempted. To illustrate this, consider an example situation in
which a factory must fill three separate customer orders, each
customer order requiring ten units of some item A. In this example,
the factory consolidates its manufacturing orders and will create
as few manufacturing orders as possible to produce the thirty total
units of item A that are needed to satisfy the three customer
orders. This would mean producing all thirty units of item A in one
manufacturing order. However, further assume in this example that
lot sizing restrictions are imposed by the equipment used to build
item A and require that each manufacturing order be for no less
than fifteen units and no more than twenty-five units. Therefore,
the thirty units of item A will need to be produced in at least two
(and possibly more) manufacturing orders.
[0017] Processing the customer orders one at a time using a factory
planning system might involve first creating a manufacturing order
for ten units of item A to fill the first customer order. To fill
the second customer order, the existing manufacturing order might
be enlarged to account for the twenty total units of item A needed
for the first and second customer orders. To fill the third
customer order, however, several possibilities might exist
depending on the sophistication of the planning system. The
existing manufacturing order might be enlarged to twenty-five
units, the maximum under the example lot-sizing restriction, and a
new manufacturing order created for the minimum fifteen units,
producing ten units more than necessary. The existing manufacturing
order might be left at twenty units, and a new manufacturing order
created for the minimum fifteen units, producing five more units
than necessary. Or, to achieve the least wasteful overall plan, the
existing manufacturing order might be reduced to fifteen units and
a new manufacturing order created for the remaining fifteen
units.
[0018] With any of these options, valuable time and computing
resources may be wasted if each step involves recomputing the total
demand for item A and reserving the items used in producing item A,
the items used in producing these items, and so on upstream. On the
other hand, if it is known at the outset that the total demand for
item A is thirty units, two manufacturing orders may be created at
the outset. As this simple example illustrates, valuable time and
computing resources may be saved by knowing which downstream
demands require item A as input and modeling those demands to
arrive at the total demand for item A before modeling the
manufacturing orders that will produce item A. Downstream demands
for an item A may include customer orders, manufacturing operations
associated with the production of another item, or any other
suitable demands.
[0019] Given a set of items, a partial ordering of the items
provides original ordering information specifying that for any two
distinct items A and B in the partial ordering: (1) A occurs before
B, (2) B occurs before A, or (3) A is unrelated to B. An extension
of a partial ordering specifies additional ordering information
that supplements the original ordering information in the partial
ordering, indicating that some first item is earlier than (referred
to where appropriate as being "less than" or "downstream of") some
second item within a final sorted list of items where the original
ordering information in the partial ordering might not have
indicated this, thereby leaving the first item and the second item
non-comparable with respect to ordering. As an example, a finished
assembly A may require component parts B and C, but if a shortage
of part C occurs, then part D may be used in place of part C. In
this example, a partial ordering would specify parts B, C, and D
all being later than (referred to where appropriate as being
"greater than" or "upstream of") part A in a final sorted list of
items. An extension to the partial ordering may specify part D
being later in the final sorted list than part C, such that an
associated logistics planning system may check for shortages of
part C before processing part D. The extension formalizes the logic
that even though part C and part D may be non-comparable with
respect to ordering under the partial ordering, a certain ordering
between them is desirable when the partial ordering is supplemented
through the extension. The additional ordering information in the
extension may in particular cases be contradictory to the original
ordering information in the partial ordering or even
self-contradictory {e.g., part D may be an alternate for part C
under a certain set of conditions, while part C may be an alternate
for part D under another set of conditions). The present invention
contemplates an extension providing any appropriate additional
ordering information to supplement the original ordering
information in a partial ordering.
[0020] Given a set of items, a total ordering of the items
specifies that for any two distinct items A and B in the total
ordering: (1) A occurs before B or (2) B occurs before A (but not
both), and therefore provides a final sorted list of items such as
that described above with reference to partial orderings. In one
embodiment, a total ordering specifies the order in which the items
are processed (e.g., at an appropriate logistics planning system)
such that the demand or other value of interest for each particular
item is known at the time the particular item is processed. A total
ordering of items may be generated according to the present
invention given a partial ordering of the items and extension data
that reflects one or more extensions to the partial ordering. An
applicable logistics planning system will preferably account for
both the partial ordering and the one or more extensions, as
reflected in a total ordering, in performing its tasks.
[0021] In one embodiment, the present invention provides a
technique for ordering items used within a workflow by obtaining
information regarding the relative order of items and arranging
these items such that they conform to the obtained information. As
an example, the present invention may arrange items to facilitate
more efficient calculation of the demand for each item, which is
dependent on the demand for all items to which the considered item
is an input. In logistics planning to facilitate the use of items
within a factory or other workflow environment, it may be desirable
to sort the items such that each output item of a workflow
operation is placed before the one or more input items of the
workflow operation. Pursuant to this ordering, one or more items at
the front of a sorted list, for which demands are known, are
analyzed first. Analysis then proceeds to subsequent items on the
list, which are inputs to the previously listed items and for which
demands will depend on the demands for the previously items to
which the subsequently listed items are inputs. This ordering is
preferably consistent with any extensions. In one embodiment, an
ordering of items generated according to the present invention
allows for more efficient calculation of demands or other values of
interest for workflow items than has been possible using previous
techniques.
[0022] Typically, production requirements are specified in routings
concerning the inputs and outputs for a particular item. For
example, a routing might be expressed as, "To produce one unit of
assembly A using routing R1, two units of part B and three units of
part C are needed." In this example, assembly A is considered to be
"downstream" of parts B and C, because a manufacturing process is
often thought of as a flow of items from the most "upstream" raw
materials or component parts to the most downstream assemblies or
finished products. To more efficiently calculate the demand or
other value of interest for all the items in the process, the above
items should be ordered such that assembly A is considered before
parts B and C. Thus, in one embodiment, according to a "First
Rule," an item downstream from another item in the workflow is
placed earlier in the ordering than the other item.
[0023] The present invention preferably takes into account that
there may be more than one way to produce assembly A, for example,
if shortages of either part B or of part C occur. Assume routing R1
(described above) is the preferred mode for making assembly A.
There may exist a routing R2 included in an extension that states,
"To produce one unit of assembly A, a unit of part D may be used in
place of a unit of part B if there is a shortage of part B." There
may also exist a routing R3 included in another extension that
states, "To produce one unit of assembly A, a unit of part E may be
used in place of a unit of part C if there is a shortage of part
C." To more efficiently calculate the demands or other values of
interest for all the items in the process, according to the First
Rule described above, assembly A is placed before parts B and C and
also before parts D and E in the total ordering. Parts B and C are
placed before parts D and E in the total ordering since demand or
other calculations for parts B and C should proceed those for parts
D and E; only if the quantities of parts B and/or C are
insufficient to meet the demand for assembly A will additional
demands for parts D and E (demands resulting from shortages of
parts Band/or C) be calculated. Thus, in one embodiment, according
to a "Second Rule," alternate parts (e.g., parts D and E) are
placed in the total ordering behind the primary parts (e.g., parts
B and C) they would replace.
[0024] In one embodiment, the present invention associates with
each item two lists. The first of these lists is referred to as "d"
for convenience and is denoted "d(G)" for an item G. This first
list will eventually be filled with all items that are downstream
of (i.e. directly or indirectly produced using) item G according to
the partial ordering. Taking a simple example, if an item X is to
be produced using a primary item P, and the primary item P has an
alternative item A, then the first list for item P will include
item X and the first list for item A will similarly include item X.
The second list is referred to as "p" for convenience and is
denoted "p(G)" for item G. This second list will eventually contain
all items not in d(G) that one or more extensions would place
downstream of item G. For the same example, where item X is to be
produced using primary item P, and primary item P has an
alternative item A, then the second list for item P will be empty
(assuming in this example that item P is not an alternative item
for some other primary item Q under a different routing). The
second list for item A will include item P, all the items in the
first list of item P, and all the items in the second list of item
P, excluding any items already in the first list of item A.
[0025] In creating a total ordering of workflow items G, the number
of items in the p and d lists of each item G are determined and
summed. The items G are then sorted such that the item G with the
lowest sum, for example, a finished assembly that is not upstream
of any other items G, is placed at the front of the total ordering.
Remaining items G are ordered such that each item G is placed in
front of any items having higher sums. This implements the First
and Second Rules described above, with downstream items G being
placed towards the front and alternative items G being placed
behind their primary items. In one embodiment, the order among any
items G with equivalent sums does not matter.
[0026] Thus, given a set of items, a partial ordering of the items,
and extension data that specifies one or more extensions to the
partial ordering, the present invention generates an ordering of
the items that extends the partial ordering while satisfying both
the partial ordering and the extensions, provided the extensions do
not contradict the partial ordering and are also not
self-contradictory. Stated another way, the total ordering
preserves the partial ordering and incorporates that portion of the
extension data that is consistent with the partial ordering and
self-consistent. The generated ordering may be a total ordering as
defined above. In alternative embodiments, the present invention
may generate an ordering that extends the partial ordering but is
not considered a total ordering. For example, within a distributed
or other multi-processor computing environment, it might be
desirable to search for items that remain non-comparable under a
partial ordering and after factoring in appropriate extension data,
and then to process these non-comparable items substantially
simultaneously using multiple processors (each of the
non-comparable items being processed by a different processor).
[0027] In the description that follows, the current item will be
referred to as "U" because it will generally be upstream of the
other items being discussed. U may be used as a loop variable or
recursive variable, as will be made clear in each step of the
process described below. It is also assumed that one reasonably
skilled in the art could use flags for such standard purposes as
preventing an item from having the same step performed on it
multiple times, preventing lists from being searched unnecessarily,
and preventing other unnecessary operations. Such techniques are
well known and would only serve to obscure the essence of the
present invention if included in the description that follows.
Therefore, they are omitted.
[0028] FIG. 1 illustrates an example process for generating a total
ordering of workflow items given a partial ordering and one or more
extensions. The process includes an initialization phase at step
10, where for each item U to be ordered the lists d(U) and p(U) are
filled with the proper items. A downstream transitive closure (DTC)
phase occurs at step 12, where for each item U to be ordered a DTC
sub-process is performed with respect to the item U. An extension
phase occurs at step 14, where each item D that should be placed
earlier than ("downstream" of) item U according to the extension
data is placed into p(U). A sort phase occurs at step 16, where the
items U are sorted to generate an ordering, such as a total
ordering, that extends the partial ordering. The initialization,
DTC, extension, and sort phases are described in further detail
below.
[0029] FIG. 2 illustrates an example initialization phase portion
of an example process for generating an ordering of workflow items
given a partial ordering and one or more extensions. The
initialization phase of the process begins at steps 20 and 22,
which collectively illustrate that for each item U to be ordered, a
loop is performed through data containing the partial ordering
until all items in the partial ordering have been considered. As an
example, routings or any other suitable information may specify the
partial ordering (i.e. for each item, specifying which items will
be placed earlier than ("downstream" of or "less than") that item
in a final sorted list). If an item D encountered should be placed
immediately ahead of item U according to the partial ordering data,
and item D is not the same as item U, then item D is added to d(U)
at step 22. For example, steps 20 and 22 may take all items of
which item U is a direct input and place these items into d(U). As
a more particular example, assume that item U is a metal pin in a
hinge assembly that is part of a door assembly. Steps 20 and 22
will place the hinge assembly into d(U), since the metal pin is a
direct component of the hinge assembly in this example. However,
steps 20 and 22 would not place the entire door assembly into d(U),
because in this example the metal pin is not a direct component of
the door assembly.
[0030] When all the items within the partial ordering data have
been considered at step 20, the process proceeds to steps 24 and
26, which collectively illustrate that for each item U to be
ordered, a loop is performed through the data containing one or
more extensions to the partial ordering until all items in the
extensions have been considered. If an item D encountered should be
placed immediately ahead of item U according to the extension data,
and item D is not the same as item U, then the item D is added to
p(U) at step 26. As just an example, assume that an extension
stated that bolt U.sub.b could replace the metal pin in the hinge
assembly described above where a shortage of the metal pin exists.
In this example, steps 24 and 26 would place the metal pin (though
not the hinge assembly) into p(U.sub.b). The loops through the
partial ordering data (steps 20 and 22) and the extension data
(steps 24 and 26) may occur concurrently or in any suitable order.
When all the items in the extension data have been considered at
step 26, the initialization phase is complete. At the end of the
initialization phase, for all items U, item U is neither a member
of d(U) nor of p(U).
[0031] FIG. 3 illustrates an example DTC phase portion of an
example process for generating an ordering of workflow items given
a partial ordering and one or more extensions. As collectively
illustrated in steps 30 through 36, the DTC phase of the process
involves looping through each item U to be ordered and performing a
DTC sub-process for each item U at step 34, until the DTC
sub-process has been performed for all such items at step 34, then
the DTC sub-process is exited.
[0032] FIG. 4 illustrates an example DTC sub-process, which may be
a function called within the DTC phase (at step 34 of FIG. 3 as
described above). If the DTC sub-process has already been performed
on item U at step 40, then the DTC sub-process is exited, we return
to the caller of the DTC sub-process, and we proceed to either step
36 of FIG. 3 or step 48 of FIG. 4 as appropriate. If the DTC
sub-process has not already been performed on item U at step 40,
then as illustrated in steps 42 through 50, the DTC sub-process
involves looping through each item D in d(U), performing the DTC
sub-process on each item D (step 46), and copying or otherwise
adding each item X in d(D) to d(U) unless item X is already in d(U)
or item X is the same as item U (step 48). Set D=next item of d(U)
at step 50; of no D then the process is exited at step 44.
[0033] To further illustrate the recursive nature of the DTC
sub-process, assume for example that item A is made from item B,
item B is made from item C, item C is made from item D, and item D
is made from item U. After initialization (FIG. 2) in this example
we expect that d(A) is empty, d(B) contains item A, d(C) contains
30 item B, d(D) contains item C, and d(U) contains item D. For the
sake of illustration, assume that the DTC sub-process is first
called on item U, this call being referred to as "DTC(U)" for
convenience. DTC(D) is called at step 46 within DTC(U), DTC(C) is
in turn called at step 46 within DTC(D), DTC(B) is in turn called
at step 46 within DTC(C), and DTC(A) is in turn called at step 46
within DTC(B). Since d(A) is empty, there is nothing to do in
DTC(A) and DTC(A) is exited to step 48 of DTC(B). Since d(A) is
empty, there is also nothing to do at step 48 within DTC(B) and
DTC(B) is exited to step 48 within DTC(C). At step 48 within
DTC(C), the contents (item A) of d(B) are copied or otherwise added
to d(C) such that d(C) now contains both items A (the contents of
d(B) just added) and B (there previously) downstream of item C.
DTC(C) is exited to step 48 within DTC(D). At step 48 within
DTC(D), the contents (items A and B) of d(C) are copied or
otherwise added to d(D), such that d(D) now contains all items A,
B, (the contents of d(C) just added) and C (there previously)
downstream of D. DTC(D) is exited to step 48 within DTC(U). At step
48 within DTC(U), the contents (items A, B, and C) of d(D) are
copied or otherwise added to d(U), such that d(U) now contains all
items A, B, C, (the contents of d(D) just added) and D (there
previously) downstream of U, which is the desired result.
[0034] The DTC sub-process considers each item D that is
immediately downstream of item U. Step 46 ensures that d(D)
contains not only the items that are immediately downstream of item
D, but all items that are downstream of item D. Step 48 adds to
d(U) all those items downstream of D (i.e. the contents of d(D)) to
d(U). Since within the loop of FIG. 4 steps 46 and 48 are performed
for each item D immediately downstream of item U, when the loop
completes d(U) will contain all items that are downstream of item
U.
[0035] FIG. 5 illustrates an example extension phase portion of an
example process for generating an ordering of workflow items given
a partial ordering and one or more extensions. As collectively
illustrated in steps 60 through 82, the extension phase of the
process involves looping through each item U to be ordered and
placing each item that is ahead of ("downstream" of) item U
according to the extension data into p(U). For an item U, at step
62, a list c(U) for the item U is emptied, the items contained in
p(U) are placed in c(U), and p(U) is emptied. At step 64, for each
item D in d(U), p(D) is added to c(U). Steps 66 through 78 involve
looping through all the items P contained in c(U). For a current
item P, if at step 70 item P is not the same as U and d(P) does not
contain item U, then item P and the items in d(P) are copied or
otherwise added to p(U) at step 72, the items in p(P) are copied or
otherwise added to c(U) at step 74, and for each item Q in d(P) the
items in p(Q) are copied or otherwise added to c(U) at step 76. In
all copies or other adds performed within the extension phase, if
the item to be added is already in d(U) or p(U), then the add
should not be performed. Also, in connection with steps 74 and 76,
if the item is item U itself or is already contained in c(U), then
the add should not be performed. These exceptions may be used to
prevent duplicates, items being common to both d(U) and p(U), and
needless work. If at step 70 item P is the same as item U or d(P)
contains item U, then the next item P within c(U) is considered.
Set P=first item in c(U) at step 66. At step 38 evaluate item P. If
item P is contained in c(U) then go to step 70. If item P is not
contained in c(U) then go to step 70. If item P is not contained in
c(U) then go to step 80.
[0036] FIG. 6 illustrates an example sort phase portion of an
example process for generating an ordering of workflow items given
a partial ordering and one or more extensions. As collectively
illustrated in steps 90 through 100, the sort phase of the process
involves looping through each item U to be ordered and for a
current item U, determining the number of items in d(U) at step 94,
determining the number of items in p(U) at step 96, and summing the
numbers of items in d(U) and p(U) at step 98. After all the items U
have been considered at step 92, the items are sorted at step 102
based on their corresponding sums to generate the desired ordering.
The generated ordering may be a total ordering as defined above. As
described above, smaller sums will be associated with items that
are ahead of other items (further "downstream"). Thus, the item
with the lowest sum is not behind ("upstream" of) any other items
and is placed at the front of the ordering. Items are ordered
according to the First and Second Rules, such that more downstream
items are placed towards the front and alternative items are placed
behind their associated primary items where consistency allows. In
one embodiment, ordering among items with equivalent sums does not
matter. Thus, given some set of items, a partial ordering of the
items, and one or more extensions to the partial ordering, an
ordering is generated that extends the partial ordering, satisfying
the partial ordering as well as the extensions, provided that the
extensions do not contradict the partial ordering and are not
self-contradictory.
[0037] Although example embodiments of the present invention have
been described, a plurality of changes, substitutions, variations,
alterations, and modifications may be suggested to one skilled in
the art, and it is intended that the invention encompass all such
changes, substitutions, variations, alterations, and modifications
as fall within the spirit and scope of the appended claims.
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