PROJECTION OF 3D IMAGE DATA ONTO A FLAT SURFACE
20230092974 · 2023-03-23
Assignee
Inventors
Cpc classification
A61B6/5223
HUMAN NECESSITIES
G06T19/00
PHYSICS
International classification
G06T19/00
PHYSICS
Abstract
In a method for transformation of a 3D representation of a part of a body, a central axis of the part of the body to be represented is defined, and a transformation surface that is axis-symmetrical to the central axis is defined. The transformation surface is transformed into a plane and a transformation of the voxels representing the part of the body oriented to the transformed transformation surface is carried out.
Claims
1. A method for transformation of a 3D representation of a part of a body, the method comprising: defining a central axis of the part of the body; defining a transformation surface that is axis-symmetrical to the central axis; spatially assigning voxels representing the part of the body to the transformation surface, wherein the spatially assigning is undertaken in a radial direction outwards from the central axis; applying an unfolding transformation to the transformation surface and the voxels assigned to the transformation surface, wherein the transformation surface is unfolded in a plane and the voxels maintain their spatial assignment to the unfolded transformation surface.
2. The method as claimed in claim 1, wherein the transformation surface includes a projection surface, and transformation of the voxels includes projecting the voxels representing the part of the body onto the projection surface.
3. The method as claimed in claim 2, wherein the voxels representing the part of the body that are arranged in a projection direction are shifted in the projection direction by a distance between the central axis and the projection surface.
4. The method as claimed in claim 3, wherein the voxels representing the part of the body that are arranged in a projection direction are shifted such that the voxels are subsequently arranged in relation to the central axis positioned outside of the projection surface.
5. The method as claimed in claim 3, wherein, after shifting of the voxels, the method comprises: transforming the projection surface into a plane, and assigning the voxels to the plane with a same transformation.
6. The method as claimed in claim 1, wherein the unfolding transformation includes a reformation, the transformation surface includes a multiplicity of cut surfaces, the cut surfaces are arranged coaxially about the central axis, and the cut surfaces define slices lying between neighboring cut surfaces, which are cut in an axial direction and transformed into a flat slice.
7. The method as claimed in claim 1, wherein the transformation surface includes a cylinder outer surface.
8. The method as claimed in claim 1, wherein the part of the body includes a hollow organ.
9. The method as claimed in claim 8, wherein the hollow organ comprises one of a heart, a bladder, a prostate, a uterus, lungs, a stomach, or a thyroid.
10. A transformation facility, comprising: an axis-positioning unit configured to define a central axis of a part of a body to be represented; a surface-positioning unit configured to define a transformation surface that is axis-symmetrical to the central axis; an assignment unit configured to spatially assign voxels representing the part of the body to the transformation surface, wherein the voxels representing the part of the body are assigned to the transformation surface in a radial direction outwards from the central axis; and a transformation unit configured to apply an unfolding transformation to the transformation surface and to the voxels assigned to the transformation surface, wherein the transformation surface is unfolded in a plane and the voxels maintain their spatial assignment to the unfolded transformation surface.
11. A medical imaging system, comprising: a scanner configured to acquire raw data from an examination object; a reconstruction unit configured to reconstruct image data based on the raw data; and a transformation unit as claimed in claim 10.
12. A non-transitory computer program product including a computer program, which is loadable into a memory of a computer device, the computer program including program sections that, when executed by the computer device, cause the computer device to carry out the method of claim 1.
13. A non-transitory computer-readable medium storing program sections that, when executed by at least one processor, cause the at least one processor to perform the method of claim 1.
14. The method as claimed in claim 4, wherein, after shifting of the voxels, the method comprises: transforming the projection surface into a plane, and assigning the voxels to the plane with a same transformation.
15. The method as claimed in claim 2, wherein the unfolding transformation includes a reformation, the transformation surface includes a multiplicity of cut surfaces, the cut surfaces are arranged coaxially about the central axis, and the cut surfaces define slices lying between neighboring cut surfaces, which are cut in an axial direction and transformed into a flat slice.
16. The method as claimed in claim 3, wherein the unfolding transformation includes a reformation, the transformation surface includes a multiplicity of cut surfaces, the cut surfaces are arranged coaxially about the central axis, and the cut surfaces define slices lying between neighboring cut surfaces, which are cut in an axial direction and transformed into a flat slice.
17. The method as claimed in claim 4, wherein the unfolding transformation includes a reformation, the transformation surface includes a multiplicity of cut surfaces, the cut surfaces are arranged coaxially about the central axis, and the cut surfaces define slices lying between neighboring cut surfaces, which are cut in an axial direction and transformed into a flat slice.
18. The method as claimed in claim 5, wherein the unfolding transformation includes a reformation, the transformation surface includes a multiplicity of cut surfaces, the cut surfaces are arranged coaxially about the central axis, and the cut surfaces define slices lying between neighboring cut surfaces, which are cut in an axial direction and transformed into a flat slice.
19. The method as claimed in claim 6, wherein the transformation surface includes a cylinder outer surface.
20. An apparatus for transforming a 3D representation of a part of a body, the apparatus comprising: a memory storing computer readable instructions; and at least one processor configured to execute the computer readable instructions to cause the apparatus to define a central axis of a part of a body to be represented, define a transformation surface that is axis-symmetrical to the central axis, spatially assign voxels representing the part of the body to the transformation surface, wherein the voxels representing the part of the body are assigned to the transformation surface in a radial direction outwards from the central axis, and apply an unfolding transformation to the transformation surface and to the voxels assigned to the transformation surface, wherein the transformation surface is unfolded in a plane and the voxels maintain their spatial assignment to the unfolded transformation surface.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] The present invention will be explained again below in greater detail by referring to the enclosed figures with the aid of exemplary embodiments. In the figures:
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DETAILED DESCRIPTION
[0050] Shown in
[0051] Shown in
[0052] Shown in
[0053] Illustrated in
[0054] The result can be seen in a diagram 50 in
[0055] Shown in
[0056] Shown in
[0057] In the step 7.II a projection cylinder is embodied as a transformation surface TF about the central axis ZA, wherein the central axis ZA at the same time forms the cylinder axis of the projection cylinder.
[0058] In the step 7.III mappings V′ of the voxels V of the organ O are created, wherein the mapped voxels V′ are arranged on the transformation surface TF in the manner shown in
[0059] In the step 7.IV the transformation surface TF is transformed into a plane TE and in the step 7.V the mapped voxels V′ arranged on the transformation surface TE are mapped as voxels V″ onto the plane TE and there embody a type of profile of the object O in the radial direction relative to the central axis ZA.
[0060] Finally, in the step 7.VI, there is a display of the created profile of the object O.
[0061] Illustrated in
[0062] The transformation facility 80 shown in
[0063] Shown in
[0064] The projection measurement data RD acquired from the detector 16 (also called raw data below) is transferred to a reconstruction unit 33 of the control facility 30a. The reconstruction unit is realized in this exemplary embodiment in the control facility 30 in the form of software on a processor. Subsequently the created three-dimensional image data BD-3D is transformed by the transformation facility 80 in the way described in conjunction with
[0065] The transformed image data T-BD created by the transformation facility 80 is then stored in a memory 32 of the control facility 30a and/or output in the usual way on the screen of the control facility 30a. It can also be read via an interface not shown in
[0066] The components of the transformation facility 80 can be realized predominantly or completely in the form of software elements on a suitable processor. In particular the interfaces between the components of the transformation facility 80 or between the transformation facility 80 and other components of the control facility 30a can also be embodied purely as software. The only requirement is that access options to suitable memory areas exist, in which the data can be suitably buffered and can be retrieved and updated again at any time.
[0067] It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections, should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or,” includes any and all combinations of one or more of the associated listed items. The phrase “at least one of” has the same meaning as “and/or”.
[0068] Spatially relative terms, such as “beneath,” “below,” “lower,” “under,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below,” “beneath,” or “under,” other elements or features would then be oriented “above” the other elements or features. Thus, the example terms “below” and “under” may encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. In addition, when an element is referred to as being “between” two elements, the element may be the only element between the two elements, or one or more other intervening elements may be present.
[0069] Spatial and functional relationships between elements (for example, between modules) are described using various terms, including “on,” “connected,” “engaged,” “interfaced,” and “coupled.” Unless explicitly described as being “direct,” when a relationship between first and second elements is described in the disclosure, that relationship encompasses a direct relationship where no other intervening elements are present between the first and second elements, and also an indirect relationship where one or more intervening elements are present (either spatially or functionally) between the first and second elements. In contrast, when an element is referred to as being “directly” on, connected, engaged, interfaced, or coupled to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between,” versus “directly between,” “adjacent,” versus “directly adjacent,” etc.).
[0070] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Also, the term “example” is intended to refer to an example or illustration.
[0071] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0072] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0073] It is noted that some example embodiments may be described with reference to acts and symbolic representations of operations (e.g., in the form of flow charts, flow diagrams, data flow diagrams, structure diagrams, block diagrams, etc.) that may be implemented in conjunction with units and/or devices discussed above. Although discussed in a particularly manner, a function or operation specified in a specific block may be performed differently from the flow specified in a flowchart, flow diagram, etc. For example, functions or operations illustrated as being performed serially in two consecutive blocks may actually be performed simultaneously, or in some cases be performed in reverse order. Although the flowcharts describe the operations as sequential processes, many of the operations may be performed in parallel, concurrently or simultaneously. In addition, the order of operations may be re-arranged. The processes may be terminated when their operations are completed, but may also have additional steps not included in the figure. The processes may correspond to methods, functions, procedures, subroutines, subprograms, etc.
[0074] Specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. The present invention may, however, be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.
[0075] In addition, or alternative, to that discussed above, units and/or devices according to one or more example embodiments may be implemented using hardware, software, and/or a combination thereof. For example, hardware devices may be implemented using processing circuitry such as, but not limited to, a processor, Central Processing Unit (CPU), a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a System-on-Chip (SoC), a programmable logic unit, a microprocessor, or any other device capable of responding to and executing instructions in a defined manner. Portions of the example embodiments and corresponding detailed description may be presented in terms of software, or algorithms and symbolic representations of operation on data bits within a computer memory. These descriptions and representations are the ones by which those of ordinary skill in the art effectively convey the substance of their work to others of ordinary skill in the art. An algorithm, as the term is used here, and as it is used generally, is conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of optical, electrical, or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.
[0076] It should be borne in mind that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, or as is apparent from the discussion, terms such as “processing” or “computing” or “calculating” or “determining” of “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device/hardware, that manipulates and transforms data represented as physical, electronic quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
[0077] In this application, including the definitions below, the term ‘module’ or the term ‘controller’ may be replaced with the term ‘circuit.’ The term ‘module’ may refer to, be part of, or include processor hardware (shared, dedicated, or group) that executes code and memory hardware (shared, dedicated, or group) that stores code executed by the processor hardware.
[0078] The module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces that are connected to a local area network (LAN), the Internet, a wide area network (WAN), or combinations thereof. The functionality of any given module of the present disclosure may be distributed among multiple modules that are connected via interface circuits. For example, multiple modules may allow load balancing. In a further example, a server (also known as remote, or cloud) module may accomplish some functionality on behalf of a client module.
[0079] Software may include a computer program, program code, instructions, or some combination thereof, for independently or collectively instructing or configuring a hardware device to operate as desired. The computer program and/or program code may include program or computer-readable instructions, software components, software modules, data files, data structures, and/or the like, capable of being implemented by one or more hardware devices, such as one or more of the hardware devices mentioned above. Examples of program code include both machine code produced by a compiler and higher level program code that is executed using an interpreter.
[0080] For example, when a hardware device is a computer processing device (e.g., a processor, Central Processing Unit (CPU), a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a microprocessor, etc.), the computer processing device may be configured to carry out program code by performing arithmetical, logical, and input/output operations, according to the program code. Once the program code is loaded into a computer processing device, the computer processing device may be programmed to perform the program code, thereby transforming the computer processing device into a special purpose computer processing device. In a more specific example, when the program code is loaded into a processor, the processor becomes programmed to perform the program code and operations corresponding thereto, thereby transforming the processor into a special purpose processor.
[0081] Software and/or data may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, or computer storage medium or device, capable of providing instructions or data to, or being interpreted by, a hardware device. The software also may be distributed over network coupled computer systems so that the software is stored and executed in a distributed fashion. In particular, for example, software and data may be stored by one or more computer readable recording mediums, including the tangible or non-transitory computer-readable storage media discussed herein.
[0082] Even further, any of the disclosed methods may be embodied in the form of a program or software. The program or software may be stored on a non-transitory computer readable medium and is adapted to perform any one of the aforementioned methods when run on a computer device (a device including a processor). Thus, the non-transitory, tangible computer readable medium, is adapted to store information and is adapted to interact with a data processing facility or computer device to execute the program of any of the above mentioned embodiments and/or to perform the method of any of the above mentioned embodiments.
[0083] Example embodiments may be described with reference to acts and symbolic representations of operations (e.g., in the form of flow charts, flow diagrams, data flow diagrams, structure diagrams, block diagrams, etc.) that may be implemented in conjunction with units and/or devices discussed in more detail below. Although discussed in a particularly manner, a function or operation specified in a specific block may be performed differently from the flow specified in a flowchart, flow diagram, etc. For example, functions or operations illustrated as being performed serially in two consecutive blocks may actually be performed simultaneously, or in some cases be performed in reverse order.
[0084] According to one or more example embodiments, computer processing devices may be described as including various functional units that perform various operations and/or functions to increase the clarity of the description. However, computer processing devices are not intended to be limited to these functional units. For example, in one or more example embodiments, the various operations and/or functions of the functional units may be performed by other ones of the functional units. Further, the computer processing devices may perform the operations and/or functions of the various functional units without sub-dividing the operations and/or functions of the computer processing units into these various functional units.
[0085] Units and/or devices according to one or more example embodiments may also include one or more storage devices. The one or more storage devices may be tangible or non-transitory computer-readable storage media, such as random access memory (RAM), read only memory (ROM), a permanent mass storage device (such as a disk drive), solid state (e.g., NAND flash) device, and/or any other like data storage mechanism capable of storing and recording data. The one or more storage devices may be configured to store computer programs, program code, instructions, or some combination thereof, for one or more operating systems and/or for implementing the example embodiments described herein. The computer programs, program code, instructions, or some combination thereof, may also be loaded from a separate computer readable storage medium into the one or more storage devices and/or one or more computer processing devices using a drive mechanism. Such separate computer readable storage medium may include a Universal Serial Bus (USB) flash drive, a memory stick, a Blu-ray/DVD/CD-ROM drive, a memory card, and/or other like computer readable storage media. The computer programs, program code, instructions, or some combination thereof, may be loaded into the one or more storage devices and/or the one or more computer processing devices from a remote data storage device via a network interface, rather than via a local computer readable storage medium. Additionally, the computer programs, program code, instructions, or some combination thereof, may be loaded into the one or more storage devices and/or the one or more processors from a remote computing system that is configured to transfer and/or distribute the computer programs, program code, instructions, or some combination thereof, over a network. The remote computing system may transfer and/or distribute the computer programs, program code, instructions, or some combination thereof, via a wired interface, an air interface, and/or any other like medium.
[0086] The one or more hardware devices, the one or more storage devices, and/or the computer programs, program code, instructions, or some combination thereof, may be specially designed and constructed for the purposes of the example embodiments, or they may be known devices that are altered and/or modified for the purposes of example embodiments.
[0087] A hardware device, such as a computer processing device, may run an operating system (OS) and one or more software applications that run on the OS. The computer processing device also may access, store, manipulate, process, and create data in response to execution of the software. For simplicity, one or more example embodiments may be exemplified as a computer processing device or processor; however, one skilled in the art will appreciate that a hardware device may include multiple processing elements or processors and multiple types of processing elements or processors. For example, a hardware device may include multiple processors or a processor and a controller. In addition, other processing configurations are possible, such as parallel processors.
[0088] The computer programs include processor-executable instructions that are stored on at least one non-transitory computer-readable medium (memory). The computer programs may also include or rely on stored data. The computer programs may encompass a basic input/output system (BIOS) that interacts with hardware of the special purpose computer, device drivers that interact with particular devices of the special purpose computer, one or more operating systems, user applications, background services, background applications, etc. As such, the one or more processors may be configured to execute the processor executable instructions.
[0089] The computer programs may include: (i) descriptive text to be parsed, such as HTML (hypertext markup language) or XML (extensible markup language), (ii) assembly code, (iii) object code generated from source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. As examples only, source code may be written using syntax from languages including C, C++, C#, Objective-C, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5, Ada, ASP (active server pages), PHP, Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, and Python®.
[0090] Further, at least one example embodiment relates to the non-transitory computer-readable storage medium including electronically readable control information (processor executable instructions) stored thereon, configured in such that when the storage medium is used in a controller of a device, at least one embodiment of the method may be carried out.
[0091] The computer readable medium or storage medium may be a built-in medium installed inside a computer device main body or a removable medium arranged so that it can be separated from the computer device main body. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium is therefore considered tangible and non-transitory. Non-limiting examples of the non-transitory computer-readable medium include, but are not limited to, rewriteable non-volatile memory devices (including, for example flash memory devices, erasable programmable read-only memory devices, or a mask read-only memory devices); volatile memory devices (including, for example static random access memory devices or a dynamic random access memory devices); magnetic storage media (including, for example an analog or digital magnetic tape or a hard disk drive); and optical storage media (including, for example a CD, a DVD, or a Blu-ray Disc). Examples of the media with a built-in rewriteable non-volatile memory, include but are not limited to memory cards; and media with a built-in ROM, including but not limited to ROM cassettes; etc. Furthermore, various information regarding stored images, for example, property information, may be stored in any other form, or it may be provided in other ways.
[0092] The term code, as used above, may include software, firmware, and/or microcode, and may refer to programs, routines, functions, classes, data structures, and/or objects. Shared processor hardware encompasses a single microprocessor that executes some or all code from multiple modules. Group processor hardware encompasses a microprocessor that, in combination with additional microprocessors, executes some or all code from one or more modules. References to multiple microprocessors encompass multiple microprocessors on discrete dies, multiple microprocessors on a single die, multiple cores of a single microprocessor, multiple threads of a single microprocessor, or a combination of the above.
[0093] Shared memory hardware encompasses a single memory device that stores some or all code from multiple modules. Group memory hardware encompasses a memory device that, in combination with other memory devices, stores some or all code from one or more modules.
[0094] The term memory hardware is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium is therefore considered tangible and non-transitory. Non-limiting examples of the non-transitory computer-readable medium include, but are not limited to, rewriteable non-volatile memory devices (including, for example flash memory devices, erasable programmable read-only memory devices, or a mask read-only memory devices); volatile memory devices (including, for example static random access memory devices or a dynamic random access memory devices); magnetic storage media (including, for example an analog or digital magnetic tape or a hard disk drive); and optical storage media (including, for example a CD, a DVD, or a Blu-ray Disc). Examples of the media with a built-in rewriteable non-volatile memory, include but are not limited to memory cards; and media with a built-in ROM, including but not limited to ROM cassettes; etc. Furthermore, various information regarding stored images, for example, property information, may be stored in any other form, or it may be provided in other ways.
[0095] The apparatuses and methods described in this application may be partially or fully implemented by a special purpose computer created by configuring a general purpose computer to execute one or more particular functions embodied in computer programs. The functional blocks and flowchart elements described above serve as software specifications, which can be translated into the computer programs by the routine work of a skilled technician or programmer.
[0096] Although described with reference to specific examples and drawings, modifications, additions and substitutions of example embodiments may be variously made according to the description by those of ordinary skill in the art. For example, the described techniques may be performed in an order different with that of the methods described, and/or components such as the described system, architecture, devices, circuit, and the like, may be connected or combined to be different from the above-described methods, or results may be appropriately achieved by other components or equivalents.
[0097] Although the present invention has been shown and described with respect to certain example embodiments, equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications and is limited only by the scope of the appended claims.
[0098] In conclusion it is pointed out once again that the aforementioned method and apparatuses merely involve preferred exemplary embodiments of the present invention and that the present invention can be varied by the person skilled in the art, without departing from the area of the present invention, provided it is predetermined by the claims. Thus the method for transformation of a 3D representation of a part of the body and the transformation facility 80 has primarily been explained with the aid of a system for recording medical image data. The present invention is however not restricted to an application in the medical area, but the present invention in principle can also be applied for the recording of images for other purposes. For the sake of completeness it is also pointed out that the use of the indefinite article “a” or “an” does not exclude the features involved also being able to be present a number of times. Likewise the use of the term “unit” does not exclude said unit consisting of a number of components, which if necessary can also be spatially distributed.