This application is related to U.S. patent application Ser. No. 11/750,763, filed on May 18, 2007, entitled “A Method and System For Understanding Social Organization in a Design and Development Process”, and having a common assignee, which application is incorporated by reference herein in its entirety.
The present application relates to socio-technical systems in general and, particularly to a method and system for analyzing existing and potential link components in socio-technical systems and measuring the overall consistency, based on a finite set of reference patterns.
Socio-technical systems include social structures of actors or people and technical structures of products that people create with their work. A socio-technical software network is a combined model that represents software developers and their relationships, software artifacts (e.g., design documents, packages, modules, classes, methods, error reports, etc.) and their relationships, linkage between developers and artifacts, and their attributes. Analyzing the importance of relationships, more generally known as linkages or links, in the model helps in describing the extent of each link's importance with respect to the overall consistency between the social structure and the technical product structure. The term consistency refers to a more general form of organizational congruence than referred to in e.g., (M. Cataldo, P. A. Wangstrom, J. D. Herbsleb, and K. M. Carley, “Identification of Coordination Requirements: Implications for the Design of Collaboration and Awareness Tools”, in Proceedings of the Conference on Computer Supported Cooperative Work (CSCW '06), Banff, Alberta, Canada, Nov. 4-8, 2006, herein referred to as “Cataldo et al.”) or (Burton, R. M. and Obel, B. Strategic Organizational Diagnosis and Design. Kluwer Academic Publishers, Norwell, Mass., 1998, herein referred to as “Burton et al.”). These measurements can be used for system diagnosis, design and/or organizational optimization. For example, such analysis may be used to determine how well a particular organization is structured to handle a particular project.
The measure of consistency addressed in the present disclosure extends well beyond the notion of congruence, which is a measurement traditionally considered in organizational design, see for example, Burton et al. The notion of consistency is based on a set of identifiable reference patterns within the network model of the social technical system. Note that these patterns are specifically related to recognizable structural aspects of the network, as opposed to organizational patterns (see, for example, “Organizational Patterns of Agile Software Development” by James Coplien and Neil Harrison, Pearson Prentice Hall, 2005). While consistency is a measurement that addresses the alignment of subnetworks that may be organized on different plane, note that it is not network (or graph) comparison of the type in the approach by e.g., “Design Pattern Detection Using Similarity Scoring” by Nikolaos Tsantalis, Alexander Chatzigeorgiou, George Stephanides, and Spyros T. Halkidis, IEEE Transactions On Software Engineering, Vol. 32, No. 11, November 2006.
Measurements may be determined that indicate how much the structure of a development organization mirrors other aspects of the project such as work items assigned to groups and individuals in the organization, and work actually carried out in terms of software components developed by the organization. Known solutions for determining such measurements use non-analytical methods of comparison. Such non-analytical methods of comparison rely on subjective assessments and may be incomplete, and difficult to automate. While a semi-analytical approach is described in Cataldo et al., that methodology uses matrix algebra to compute a congruence metric and concerns tasks, however, but does not address measuring importance of a given link, does not analyze the network directly, and does not analyze components of the work product output by tasks. Further, both non-analytical and semi-analytical methods do not consider detailed structure of the underlying components in the comparison.
Therefore, an improved methodology, for example, which takes into account various attributes and which can be automated is desirable. Further, it is desirable to have such methodology provide measurements that are time phased, for example, to determine how variations of level of such measurements in time within the same project influence performance and quality. It is also desirable to have such methodology provide a measurement of importance at the component (link) level, as well as a consistency measurement at the overall system level.
A method and system for scoring a plurality of component links in a socio technical system are provided. The socio technical system may comprise a plurality of components representing people and objects, the plurality of components links representing a plurality of relationships between the plurality of components. The method in one aspect may comprising determining a measure of consistency relative to a network of people components and a network of object components in a socio technical system, the network of people components including components representing people and one or more links between the components representing people, and the network of object components including components representing objects worked on by at least some of the components representing people and one or more links between the components representing objects. The method may also comprise determining a measure of contribution to the measure of consistency for one or more links between said components, based on presence or absence of said one or more links in the social technical system. The measure of contribution and the measure of consistency can be used for analyzing and structuring work group in a project.
A system for scoring a plurality of component links in a social technical system in one aspect may include means such as computer processor, module, and/or circuitry for providing the functionalities for the above-described method.
Further features as well as the structure and operation of various embodiments are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.
A method and system of the present disclosure in one embodiment measures relationships or coordination by comparing an abstract graph model of social structures of people (also referred to as a “social network”) with an abstract graph representation of the technical structure of the work product. The comparison is facilitated through the use of “joins” between the two graph that identify connections between node entities in the social graph with node entities in the technical graph. The method and system of the present disclosure in one embodiment considers one or more aspects of mutual existing structural components as well as mutual non-existence of structural components in the resulting metric. The method and system of the present disclosure in one embodiment provides the flexibility for calibrating the measurement to reflect key requirements of measurement interest in the environment and application.
Models of socio-structure and technical-structure and joins are represented electronically. A method and system of the present disclosure in one embodiment automatically computes measurement of relationships joins) from the socio-structure and technical-structure models. For instance, given two graphs and a set of joins between them, a measurement may be provide, for example, on a scale of 0 to 1, to describe how “consistent” they are. Other measurements may include predicting the existence of arcs in a graph that does not have full information.
The following notation is used by the model:
The social network model shown in
Node tie collaboration consistency refers to a case whenever a pair of individuals (people) both have a relationship with a work artifact, then one expects to see a path between the people in the social network. This can be expressed conceptually as follows. Define Γs(GS, GP, J, 1) to be the number of times that there exist s0εS and pi, PjεP, with i≠j, such that (pi, s0), (pj, s0)εJ. For any natural number k>=2, let Γs(GS, GP, J, k) denote the number of times that there exist s0εS and pi, pjεP, with i≠j, such that (pi, s0), (pj, s0)εJ and there is no geodesic (i.e. a shortest path between a pair of nodes, where the path length is measured by the number of links) from pi to pj of length less than or equal to k−1. Similarly, define Λs(GS, GP, J, 1) is defined to be the number of times that there exist s0εS and pi, pjεP, with i≠j, such that (pi, s0), (pj, s0)εJ and (pi, pj)εEP. For k>−2, let Λs(GS, GP, J, k) denote the number of times that there exist s0εS and pi, pjεP, with i≠j, such that (pi, s0), (pj, s0)εJ and there is a geodesic from pi to pj of length less than or equal to k. Then for all nonzero natural numbers k, define the k-path collaboration (on a single artifact) pattern consistency by the ratio
Define ρs,0:=0.
Arc mirroring coordination consistency refers to the following: if work artifact sr has a dependency on work artifact sq, then one expects person pj to be connected to artifact sq either directly or via a path in the people graph by Gp(P,Ep). This concept can be expressed formally as follows. Define Γd(GS, GP, J, 0) to be the number of times that there exist sq, srεS, q≠r, and pjεP such that (sq, sr)εAS and (pj, sr)εJ. Define Γd(GS, GP, J, 1) to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ. For any natural number k>=2, let Γd(GS, GP, J, k) denote the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ and there is no geodesic from pi, to pj of length less than or equal to k−1.
Similarly, define Λd(GS, GP, J, 0) to be the number of times that there exist sq, srεS, q≠r, and pjεP such that (sq, sr)εAS and (pj, sr)εJ. Define Λd(GS, GP, J, 1) to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ and pi, pjεEp. For k>=2, let Λd(GS, GP, J, k) denote the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ and there is a geodesic from pi, to pj of length k. Then for all nonzero natural number k, define the k-path coordination (on a pair of dependent artifacts) pattern consistency by the ratio
Note that ρl,k (i.e., ρd,k where d is equal to 1) is equivalent to the value of the “congruence” metric in Cataldo et al. under certain assumptions.
The method and system also may aggregate the individual pattern consistency metrics ρs,k and ρd,k into organizational consistency metrics Ωs and Ωd. Observe that for any given socio-technical network with a people node set of size n, the maximum length of any path in the people graph Gp(P, Ep) is given by n−1. Therefore, the pattern consistency metrics ρs,k and ρd,k only make sense for k=0, 1, 2, . . . , n−1. Let {λk, k=0, 1, 2, . . . , n−1} be any finite, nonnegative, non-increasing sequence such that
Then organizational collaboration consistency (node tie) metric may be defined in the following way:
Likewise, organization coordination consistency (arc mirroring) metric may be defined as follows:
Geometric series: Let 0<r<1 and define λk:=crk, where
Power series: For any natural number p=1, 2, . . . , let
and define
Function-based series: Let ƒ:[0,∞)→(0,∞) be a decreasing function. Let
and define
Then one may choose a specific function ƒ according to specific requirements. For example, one may choose ƒ(x)=e−zx
The choice of the parameters r (geometric series), p (power series) or z (exponential function based series) may affect how quickly the organizational consistency parameters λk tend to zero. This choice may also affect how much weight is given to the first pattern consistency metric ρ*,l (here * represents either s or d).
Recommended default parameters are r=0.75, p=1 and z=0.05. These default settings yield similar results in the combined organizational consistency metrics for each choice of series type.
The following illustrates an algorithm in one embodiment that finds all consistency ratios, ρs,k, in which δs,k represents expected collaboration pattern and λs,k represents observed collaboration pattern:
The above algorithm simultaneously computes all k-path collaboration pattern consistency ratios, and identifies gaps. Since the maximum path length in a network with np nodes is np-1, it starts by initializing to zero the counters used to find the denominator and numerator values respectively. The 2nd step finds all point to point geodesic (shortest path based on number of links) values. This step can be accomplished by iterating a standard shortest path algorithm such as those known by Dijkstra, or Floyd Warshall. Step 3 iterates by considering each artifact node and all of the joins (i.e., links emanating from the people nodes into the artifact nodes) that connect to it. For each unique pair of joins linked into a common artifact, the algorithm looks to see if there are two distinct individuals at the other ends of the join pair, and if there is, the denominator is incremented. If there is also a path between these two distinct individuals, then the appropriate numerator counter is incremented. During the main step, whenever there is no path between a pair of nodes for which the method and system expect to see communication, a gap is noted. These gaps are useful to derive the importance values of the individual links—i.e. how much the overall collaboration would be improved by adding the link. After step 3, step 4 computes the remaining denominator values by recursion. This works because, between any pair of nodes, if there is a path, it is either of length 1, 2, . . . , or np-1 in length. In step 5, the ratios are computed—that is, the number of observed patterns are divided by the number of patterns expected for perfect collaboration interaction.
The following illustrates an algorithm in one embodiment that finds all consistency ratios, ρd,k, in which δd,k represents expected coordination pattern and λd,k represents observed coordination pattern:
The algorithm above works in the similar way as the previous algorithm, except that in step 3 step, it iterates by considering each link between pairs of software artifact nodes and then each unique pair of joins where one is connected to one of the software artifact nodes and one to the other. Both algorithms perform in polynomial time.
As described above, consistency is measured between conceptual planes in the socio-technical system. For example, in
The following illustrates a way to derive link importance measurements for links. Links that are not in the graph are also referred to as potential links in the present disclosure. These links may include between people, artifacts, or new joins, or any other links between and among components of socio-technical system being considered. Link importance measurements are also referred to as scores, that is, the degree to which a link or a potential link contributes to the overall consistency measurement. The determined scores then may be ordered to provide a ranking among the links.
Path collaboration (on a single artifact) pattern consistency and the k-path coordination (on a pair of dependent artifacts) pattern consistency (for example, each mathematically described by the ratios defined, as well as computationally described by the algorithms, above) provide measurements, both in their individual and weighted combinations, that are attributes of the socio-technical system as a whole. Each measurement may take on a value between zero and one, and can be interpreted as a degree to which the socio-technical system is consistent. That is, a value of zero indicates no consistency, a value of one indicates complete consistency, and a value of u where 0<u<1 (i.e. u is greater than zero as well as less than one) can be interpreted as the percentage of consistency achieved. For instance, a socio-technical system can be considered to have a socio part comprising people and technical part comprising objects, although not limited to such, and consistency may be considered as a measurement relative to the comparison of the parts. It is also possible to have a socio-technical system with additional parts.
For some socio technical systems, a higher consistency measurement (e.g., close to or equal to the value of one) may be considered better than a lower measurement. For example, in an organization working on a common set of goals, high degree of communication or relationship may be considered valuable to the workings of the organization. In other socio-technical systems, a lower measurement (e.g., close to or equal to the value of zero) may be considered more desirable. For example, consider a supply chain used to create IEDs (improvised explosive devices) by a group of terrorists. This may be modeled as a socio-technical system, in which it is preferred to see or drive the system to a low consistency measurement, signifying disruption in the effort.
Related to each component link is a value, referred in this disclosure as a “score” or “importance value,” which measures the contribution by the link to the overall consistency. Note that a component link's score may be influenced by its inclusion (or not) in observed reference patterns. For example, a score may be higher if a component link is observed to connect two people who both happen to work on more than one of the same artifacts. A score may also be higher on a link between two people who happen to work on many different artifacts where the different artifacts have a number of dependencies between them.
In one embodiment, a score given to a component link may be derived by computing a system-wide consistency measurement twice: once with and once without the link. On the other hand, general analytical forms for the score of a component link (be it a component link between people, a link between software artifacts, or a link joining a person and an artifact, or any other joins) can be written in terms of the same notation given above. For example, the following derives several views of importance measurements (or scores) for the different types of links in one embodiment of the present disclosure. The derivations described below is shown as examples only. Other derivation methods may be used.
The following describes the importance or impact of introducing a link between people in a social-technical network in detail in one embodiment. Suppose that i≠j and (pi, pj)∉EP. One may socially engineer the socio-technical network by introducing person pi and pj to one another. This corresponds to adjoining edge (pi, pj) to the people graph GP. Let GP(pi, pj) be the graph obtained by adjoining edge (pi, pj) to GP. It is desired to measure the impact that adding edge (pi, pj) to GP would have on the 1-path collaboration consistency pattern measure ρs,l and the 1-path coordination measure pd,l.
Recall that by collaboration consistency the following is meant: whenever a pair of individuals (people) both have a relationship with a work artifact, then one expects to see a path between the people in the social network. Recall that Γs(GS, GP, J, 1) is defined to be the number of times that there exist s0εS and pi, pjεP, with i≠j, such that (pi, s0), (pj, s0)εJ. Moreover, Λs(GS, GP, J, 1) is defined to be the number of times that there exist s0εS and pi, pjεP, with i≠j, such that (pi, s0), (pj, s0)εJ and (pi, pj)εEP. The 1-path collaboration consistency measure is given by
Now suppose that there exists s0εS such that (pi, s0), (pj, s0)εJ. Then
Γs(GS,GP(pi,pj),J,1=Γs(GS,GP,J,1
and
Λs(GS,GP(pi,pj),J,1)=Λs(GS,GP,J,1)+1.
Therefore the net impact of adding the edge (pi, pj) to GP is given by
On the other hand, if (pi, pj)∉EP and there does not exist s0εS such that (pi, s0), (pj, s0)εJ, then
Λs(GS,GP(pi,pj),J,1)=Λs(GS,GP,J,1)
and
Γs(GS,GP(pi,pj),J,1)=Γs(GS,GP,J,1)
so the net impact of adding the edge (pi, pj) to GP is 0. In other words, there is net impact on ρs,l of adding edge
if there exists s0εS such that (pi, s0), (pj, s0)εJ, 0 otherwise.
Recall that by coordination consistency the following is meant: if work artifact sr has a dependency on work artifact sq, and if person pj is connected to artifact sr, then one expects person pj to be connected to artifact sq. Recall that δs(GS, GP, J, 1) is defined to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS, and (pi, sq), (pj, sr)εJ. Moreover, Λd(GS, GP, J, 1) is defined to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ and (pi, pj)εEP. The 1-path coordination consistency measure is given by
Continue to suppose that i≠j and (pi, pj)∉EP. Now consider the impact that adding edge (pi, pj) would now have on the consistency pattern measure ρd,l. As before, let GP(pi, pj) be the graph obtained by adjourning edge (pi, pj) to GP. Now suppose that there exist sq, srεS, q≠r such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ. Then Γd(GS, GP(pi, pj), J, 1)=Γd(GS, GP, J, 1) and Λd(GS, GP(pi, pj), J, 1)=Λd(GS, GP, J, 1)+1. Therefore the net impact of adding the edge (pi, pj) to GP is given by
On the other hand, if (pi, pj)∉EP and there does not exist sq, srεS, q≠r such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ, then Λd(GS, GP(pi, pj), J, 1)=Λd(GS, GP, J, 1) and Γd(GS, GP(pi, pj), J, 1)=Γd(GS, GP, J, 1) so the net impact of adding the edge (pi, pj) to GP is 0.
In other words, there is net impact on ρs,l of adding edge
if
there exists s0εS, q≠r such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ, 0 otherwise.
The following describes the importance or impact of assigning new joins in a socio-technical network in detail in one embodiment. Suppose that (p0, s0)∉J. One may engineer the socio-technical network by assigning person p0 to task s0. This corresponds to adjoining arc (p0, s0) to the join set J. Let J(p0, s0) be the graph obtained by adjoining arc (p0, s0) to J. It is desirable to measure the impact that adding arc (p0, s0) to J would have on the 1-path collaboration consistency pattern measure ρs,l and the 1-path coordination consistency measure ρd,l.
Recall that by collaboration consistency the following is meant: whenever a pair of individuals (people) both have a relationship with a work artifact, then one expects to see a path between the people in the social network. Recall that Γs(GS, GP, J, 1) is defined to be the number of times there exist s0εS and pi, pjεP with i≠j, such that (pi, s0), (pj, s0)εJ. Moreover, Λs(GS, GP, J, 1) is defined to be the number of times there exist s0εS and pi, pjεP with i≠j, such that (pi, s0), (pj, s0)εJ and (pi, pj)εEP. The 1-path collaboration consistency measure is given by
In the following discussion, it is assumed that there exists pi with pi≠p0 such that (pi, s0)εJ. This assumption means that every artifact in the socio-technical network has at least one person assigned to it a priori. For the sake of simplicity, first examine the case that there exists a unique piεP with pi≠p0 such that (pi, s0)εJ. Now suppose that (pi, p0)∉EP.
Then
Γs(GS,GP,J(p0,s0),1)=Γs(GS,GP,J,1)+1
and
Λs(GS,GP,J(p0,s0),1)=Λs(GS,GP,J,1).
Therefore the net impact of adding the arc (p0, s0) to J is given by
On the other hand, if (pi, p0)εEP, then
Γs(GS,GP,J(p0,s0),1)=Γs(GS,GP,J,1)+1
and
Λs(GS,GP,J(p0,s0),1)=Λs(GS,GP,J,1)+1
so the net impact of adding the arc (p0, s0) to J is given by
In other words, there is net impact on ρs,l of adding arc
The assumption on the uniqueness of pi is not realistic. Let g denote the number of distinct people pi such that pi≠p0 and (pi, s0)εJ. Let l denote the number of those distinct people pi such that pi≠p0, (pi, s0)εJ and (pi, s0)εEP. Then there is net impact on ρs,l of adding arc
Recall that by coordination consistency meant the following: if work artifact sr has a dependency on work artifact sq, and if person pj is connected to artifact sr, then one expects person pj to be connected to artifact sq. Recall that Γd(GS, GP, J, 1) is defined to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ. Moreover, Λd(GS, GP, J, 1) is defined to be the number of times that there exist sq, srεS, q≠r, and pi, pjεP, i≠j, such that (sq, sr)εAS and (pi, sq), (pj, sr)εJ and (pi, pj)εEP. The 1-path coordination consistency measure is given by
Now assume that there exists sqεS with sq≠s0 such that either (sq, s0)εAS or (s0, sq)εAS. This assumption means that s0 is not an isolated software artifact. Moreover, it is assumed that there exists piεP with pi≠p0 such that (pi, sq)εJ. This assumption means that every artifact in the socio-technical network has at least one person other than p0 assigned to it a priori. In the case that either of these assumptions does not hold, simply define the net impact of the addition of arc (p0, s0) to be 0.
For the sake of simplicity, first examine the case that there exists a unique piεP with pi≠p0 such that (pi, sq)εJ. Now suppose that (pi, p0)∉EP. Then
Γd(GS,GP,J(p0,s0),1)=Γd(GS,GP,J,1)+1
and
Λd(GS,GP,J(p0,s0),1)=Λd(GS,GP,J,1).
Therefore the net impact of adding the arc (p0, s0) to J is given by
On the other hand, if (pi, p0)εEP, then
Γd(GS,GP,J(p0,s0),1)=Γd(GS,GP,J,1)+1
and
Λd(GS,GP,J(p0,s0),1)=Λd(GS,GP,J,1)+1
In other words, there is net impact on ρd,l of adding arc
The assumption on the uniqueness of pi is not realistic. Let g denote the number of distinct people pi such that pi≠p0 and (pi, sq)εJ. Let l denote the number of those distinct people pi such that pi≠p0, (pi, sq)εJ, and (pi, p0)εEP. Then there is net impact on ρd,l of adding arc
Once a score for all component links have been established using a process such as the one described above, then each component link can also be assigned a ranking, for example, by ordering either in ascending or descending order, depending on the application. As an example, the list of component links and their scores may be sorted into descending order. The component link with the largest score is given the rank of 1, the next highest is given rank 2, and so on. Component links with identical (i.e. tied) scores may be assigned the same (equal) rank. A step in the ranking may or may not be skipped when there are ranking ties.
Different from the weights considered to combine consistency measurements, described in the equations previously, there may be weights assigned to component links and nodes that are used in computations of the component link scores. These weights may be associated with attributes of the component links and nodes. For example, a component node that represents a software artifact may have an associated complexity measurement, such as “cyclomatic complexity” developed by Thomas McCabe (reference IEEE Transactions On Software Engineering, Vol. SE-2, No. 4, December 1976, pp 308-320 by Thomas McCabe). Many other examples of complexity metrics, general metrics, and other attributes exist. These node attributes may be considered as weights that impact the scores. For example, if a component link connects two people who both happen to work on the same artifact and the artifact happens to have a higher weight, then the component link score may be bumped up proportionally, for example, considering the value of the weight in the overall collection of weights.
The method and system of the present disclosure in one embodiment provides mechanism for quantifying alignments or gaps between working groups and their work product and/or any other work factors. The quantification can be used to re-align the work group structure and/or the work product structure, for example, to improve an overall outcome, for instance, for more productive collaborative development.
While the examples shown above were related to socio-technical graphs involving software development, the method and system may be applied in any other development and design project, including but not limited to hardware, system, manufacturing, etc. Further, the method and system of the present disclosure may be used in general graph comparison, not limited to socio-technical graphs.
The system and method of the present disclosure may be implemented and run on a general-purpose computer or computer system. The computer system may be any type of known or will be known systems and may typically include a processor, memory device, a storage device, input/output devices, internal buses, and/or a communications interface for communicating with other computer systems in conjunction with communication hardware and software, etc.
The terms “computer system” and “computer network” as may be used in the present application may include a variety of combinations of fixed and/or portable computer hardware, software, peripherals, and storage devices. The computer system may include a plurality of individual components that are networked or otherwise linked to perform collaboratively, or may include one or more stand-alone components. The hardware and software components of the computer system of the present application may include and may be included within fixed and portable devices such as desktop, laptop, server.
The embodiments described above are illustrative examples and it should not be construed that the present invention is limited to these particular embodiments. Thus, various changes and modifications may be effected by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.
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