Devices and/or components of devices are often capable of performing certain functionalities that other devices and/or components are not configured to perform and/or are not capable of performing. In such scenarios, it may be desirable to adapt one or more systems to enhance the functionalities of devices and/or components that cannot perform the one or more functionalities.
In general, in one aspect, the invention relates to an equipment rack that includes a modular compute unit, a modular processing unit disposed in the modular compute unit, an air mover unit disposed in the modular processing unit, where the modular processing unit includes an air mover and an air mover holder.
In general, in one aspect, the invention relates to a method for installing a modular processing unit in a modular compute unit, where the method includes identifying a desired orientation of the modular processing unit, identifying a gaseous flow direction of the modular compute unit, making a determination, based on the desired orientation and the gaseous flow direction, that an air mover of the modular processing unit needs to be reversed, reversing, based on the determination, the air mover, and affixing the modular processing unit to the modular compute unit.
Other aspects of the invention will be apparent from the following description and the appended claims.
Specific embodiments will now be described with reference to the accompanying figures. In the following description, numerous details are set forth as examples of the invention. One of ordinary skill in the art, having the benefit of this detailed description, would appreciate that one or more embodiments of the present invention may be practiced without these specific details and that numerous variations or modifications may be possible without departing from the scope of the invention. Certain details known to those of ordinary skill in the art may be omitted to avoid obscuring the description.
In the following description of the figures, any component described with regard to a figure, in various embodiments of the invention, may be equivalent to one or more like-named components shown and/or described with regard to any other figure. For brevity, descriptions of these components may not be repeated with regard to each figure. Thus, each and every embodiment of the components of each figure is incorporated by reference and assumed to be optionally present within every other figure having one or more like-named components. Additionally, in accordance with various embodiments of the invention, any description of any component of a figure is to be interpreted as an optional embodiment, which may be implemented in addition to, in conjunction with, or in place of the embodiments described with regard to a corresponding like-named component in any other figure.
Throughout the application, ordinal numbers (e.g., first, second, third, etc.) may be used as an adjective for an element (i.e., any noun in the application). The use of ordinal numbers is not to imply or create any particular ordering of the elements nor to limit any element to being only a single element unless expressly disclosed, such as by the use of the terms “before”, “after”, “single”, and other such terminology. Rather, the use of ordinal numbers is to distinguish between the elements. By way of an example, a first element is distinct from a second element, and the first element may encompass more than one element and succeed (or precede) the second element in an ordering of elements.
As used herein, the term ‘operatively connected’, or ‘operative connection’, means that there exists between elements/components/devices a direct or indirect connection that allows the elements to interact with one another in some way (e.g., via the exchange of information). For example, the phrase ‘operatively connected’ may refer to any direct (e.g., wired or wireless connection directly between two devices) or indirect (e.g., wired and/or wireless connections between any number of devices connecting the operatively connected devices) connection.
In general, embodiments of the invention relate to systems and methods for providing a removably attachable air mover to a modular processing unit that, once removed, may be reversed and re-attached to the modular processing unit. Thus, the modular processing unit may be installed at various orientations in a modular compute unit, regardless of the existing direction of gaseous flow. That is, a modular processing unit may installed in a preferred direction, and the air mover of that modular processing unit can be oriented to match the direction of the already-existing gaseous flow.
The invention may provide one or more advantages. In one embodiment of the invention, manufacturing of modular processing unit becomes less burdensome and/or costly because, instead of manufacturing two different modular processing units (each allowing for gaseous flow in opposite directions), a single modular processing unit may be manufactured that allows an installer to reverse the air mover, as needed, to match the configuration of the system in which the modular processing unit is being installed.
Another advantage of various embodiments of a reversible modular air mover is the installer and/or end users of the modular processing unit are provided flexibility and customizability of the configuration of the modular compute unit (in which the modular processing unit is installed). That is, without the ability to re-orient (reverse) a modular processing unit, the geometric configuration of devices within the modular compute unit is limited. However, as one embodiment of the invention proposes, a modular processing unit may be installed in either the front or back of a modular compute unit, thereby providing additional options for the layout of a modular compute unit.
Another advantage of various embodiments of a reversible modular air mover is that servicing and replacement of the air mover becomes easier. As the air mover is designed to easily detach—replacing, upgrading, testing, or generally servicing the air mover also becomes less burdensome compared an air mover that is more permanently affixed. The invention is not limited to the aforementioned advantages.
In one or more embodiments of the invention, the equipment rack (100) is a physical structure. The equipment rack (100) may include a frame (e.g., frame (106)) that may be adapted to facilitate storage of one or more modular compute unit(s) (102, 104) in a high-density computing environment. The high-density computing environment may be, for example, a data center or another type of location where one or more modular compute unit(s) (102, 104) are located.
The frame (106) may be constructed using any number of suitable materials. For example, portions of the frame (106) may be implemented using metals (e.g., steel, aluminum, etc.). In another example, portions of the frame (106) may be implemented using polymers (e.g., polyamides, polycarbonates, polyester, polyethylene, polypropylene, polystyrene, polyurethanes, polyvinyl chloride, etc.). As another example, portions of the frame (106) may be implemented using rubber (e.g., latex, styrene-butadiene rubbers, etc.). One of ordinary skill in the art, having the benefit of this detailed description, would appreciate that the frame (106) may be implemented using any quantity and combination of suitable materials without departing from the scope of this invention.
To facilitate mounting of one or more modular compute unit(s) (102, 104), the frame (106) may include any number of structural members (e.g., beams, brackets, bars, etc.) and any number of mechanical mounting points (e.g., holes, threaded portions, etc.) disposed on the structural members to facilitate storage of a modular compute unit (102, 104). Different structural members may have different shapes, sizes, and/or other physical characteristics. The shapes, sizes, and/or other physical characteristics of the structural members may be adapted to enable the structural members to be mechanically connected (e.g., permanently or reversibly connected) to each other to form a predetermined structure. The predetermined structure may be, for example, a cage, box, or other type of structure that facilitates positioning and/or orienting one or more modular compute unit(s) (102, 104).
When all, or a portion, of the structural members are mechanically connected to each other, the mechanical mounting points may be disposed at predetermined locations. The predetermined locations may correspond to similar predetermined locations on a modular compute unit (102, 104) where mechanical mounting elements, complementary to the mechanical mounting points, are disposed. By doing so, the frame (106) may be adapted to position a modular compute unit (102, 104) in locations and/or orientations suitable for a high-density computing environment, or another environment in which a modular compute unit (102, 104) may be located. The mechanical mounting points may be any type of physical structure for attaching (permanently or reversibly) a modular compute unit (102, 104) to the frame (106). There may be any number of mechanical mounting points to facilitate the attachment of any number of corresponding modular compute units (102, 104).
To facilitate attachment of a modular compute unit (102, 104) to the frame, a chassis of the modular compute unit (102, 104) may include any number of mechanical mounting elements. The mechanical mounting elements may be located at predetermined locations. For example, a mechanical mounting element may be a rail disposed on a side of a chassis of a modular compute unit (102, 104). The location of the rail may correspond to a position on the frame (106) where a rail guide (i.e., a complementary mechanical mounting point) is disposed. The rail and the rail guide may facilitate attachment of a modular compute unit (102, 104) to the frame (106) which, in turn, positions and orients a modular compute unit (102, 104) relative to the frame (106) and equipment rack (100), generally.
Modular compute units (102, 104) may have different configurations and/or uses within the equipment rack (100). In one or more embodiments of the invention, an equipment rack (100) may include any number and combination of modular compute units (102, 104) adapted for any number of different uses and/or sizes without departing from the scope of the invention. By way of example, modular compute unit A (102) may execute a server for hosting a website, whereas modular compute unit B (104) may host a media server, which stores media files. Further, modular compute unit B (104) may be of a larger physical size than modular compute unit A (102) and, consequently, may be capable of housing more and/or larger modular processing units therein.
While the equipment rack (100) of
In one embodiment of the invention, a chassis (212) forms the exterior structure of the modular compute unit (202). A chassis (212) may be a mechanical device that is adapted to (i) facilitate attachment of a modular compute unit (202) to a frame of an equipment rack, (ii) house one or more modular processing unit(s) (204, 206), (iii) provide electrical (electrical power and/or data) operative connection(s) to one or more modular processing unit(s) (204, 206), and/or (iv) provide thermal management services to one or more modular processing unit(s) (204, 206) of the modular compute unit (202). More detail regarding the description of a modular processing unit (204, 206) and the components therein is provided in the description of
The chassis (212) of the modular compute unit (202) may be constructed using any number of suitable materials. For example, portions of the chassis (212) may be implemented using metals (e.g., steel, aluminum, etc.). In another example, portions of the chassis (212) may be implemented using polymers (e.g., Polyamides, polycarbonates, polyester, polyethylene, polypropylene, polystyrene, polyurethanes, etc.). In a still further example, portions of the chassis (212) may be implemented using rubber (e.g., latex, styrene-butadiene rubbers, etc.) The chassis (212) may be implemented using any quantity and combination of suitable materials without departing from the invention.
To house the one or more modular processing unit(s) (204, 206), the chassis (212) may include one or more internal volumes. For example, the internal volumes may facilitate disposing of the one or more modular processing unit(s) (and/or other devices) within a modular compute unit (202). The internal volumes may have a shape or other characteristic(s) that facilitates disposing of the one or more modular processing unit(s). For example, an internal volume of the chassis (212) may be a rectangular void capable of housing one or more modular processing unit(s) (204, 206) and/or other devices. In one embodiment of the invention, a chassis (212) may provide one or more exterior sides (e.g., exterior walls) that form the outer structure of the modular compute unit (202). In one embodiment of the invention, the exterior sides provide mounting points (e.g., holes, threaded portions, etc.) and/or other means for affixing one or more modular processing unit(s) (204, 206) to the inside of the modular compute unit (202).
In one embodiment of the invention, a modular compute unit (202) provides electrical power (e.g., power) to one or more modular processing unit(s) (204, 206) via one or more conductive operative connection(s) (e.g., metallic contacts and/or wire(s) terminated with a plug and socket). In turn, in one embodiment of the invention, one or more modular processing unit(s) (204, 206) provides power to one or more components of the modular processing unit (e.g., air mover unit A (208), air mover unit B (206)). The modular compute unit (202) may be provided power from an equipment rack (not shown) or via some other source.
To provide thermal management services to one or more modular processing unit(s) (204, 206) and/or other devices, a modular compute unit (202) may facilitate the flow of gas proximate to the one or more modular processing unit(s) (204, 206) and/or other devices. By doing so, the thermal state (i.e., temperature) of the aforementioned devices may be regulated (i.e., maintained within a preferred temperature range).
For example, a modular compute unit (202) may include one or more vents that allow a gas from a first side (e.g., “front”) of a modular compute unit (202) to flow into, through, and out a second side (e.g., “back”) of the a modular compute unit (202). The gas, flowing through the modular compute unit (202), may be at a different temperature than the modular processing unit(s) (204, 206) and/or other devices. Consequently, thermal exchange between the flow of gas and the aforementioned devices may occur resulting in the temperature of the aforementioned devices changing. By doing so, heat generated by the aforementioned devices may be expelled from the devices thereby regulating the temperature of the aforementioned devices.
For the example modular compute unit (202) shown in
As shown in
Further, in one embodiment of the invention, like the modular compute unit (202), a modular processing unit (204, 206) provides thermal management services to one or more electronic component(s) (not shown) within the modular processing unit. A modular processing unit (204, 206) may facilitate the flow of gas proximate to the one or more electronic component(s) and/or other devices by including one or more vents that allow a gas from a first side (e.g., “front”) of a modular processing unit (204, 206) to flow into, through, and out a second side (e.g., “back”) of the modular processing unit (204, 206). The gas, flowing through the modular processing unit (204, 206), may be at a different temperature than the modular processing unit(s) (204, 206) and/or other devices. Consequently, thermal exchange between the flow of gas and the aforementioned devices may occur resulting in the temperature of the aforementioned devices changing. By doing so, heat generated by the aforementioned devices may be expelled from the devices thereby regulating the temperature of the aforementioned devices.
Accordingly, in one embodiment of the invention, the air mover (not shown) (of the air mover unit (208, 210)) is re-oriented such that the air mover causes gaseous matter to flow in the same direction as caused by other air movers (not shown) already operating in the modular compute unit (202). Thus, an air mover may need to be reversed depending on (i) the default orientation of the air mover, (ii) the direction of gaseous flow in the modular compute unit (202), and/or (iii) whether the modular processing unit (204, 206) is installed in the front or back of a modular compute unit (202). More detail regarding the description of reversing the air mover is provided in the description of
While
In one or more embodiments of the invention, the modular processing unit (304) may include any number of structural members (e.g., beams, brackets, bars, etc.) and any number of mechanical mounting points (e.g., holes, threaded portions, etc.) disposed on the structural members to facilitate the attachment of an air mover unit (308). Different structural members may have different shapes, sizes, and/or other physical characteristics. The shapes, sizes, and/or other physical characteristics of the structural members may be adapted to enable the structural members to be mechanically connected to each other to form a predetermined structure. The predetermined structure may be, for example, a cavity, cutout, or other type of structure that facilitates positioning, orienting, and/or attaching the air mover unit (308) to the modular processing unit (304).
When all, or a portion, of the structural members are mechanically connected to each other, the mechanical mounting points of the modular processing unit (304) may be disposed at predetermined locations. The predetermined locations may correspond to similar predetermination locations on the air mover unit (308) where mechanical mounting elements, complementary to the mechanical mounting point of the modular processing unit (304) are disposed. The mechanical mounting points may be any type of physical structure for removably attaching an air mover unit (308) to a modular processing unit (304).
For example, an air mover unit (308) may attach to a modular processing unit (304) via rigid fasteners (e.g., screws, nails, pins, etc.) that traverse one or more aligned mechanical mounting points of the modular processing unit (304) and air mover unit (308). As another example, an air mover unit (308) may attach to a modular processing unit (304) via mechanical latching means (e.g., clip(s), sliding rails) that utilize the elasticity (e.g., flexibility) and/or shape of the materials of the air mover unit (308) and/or modular processing unit (304) to removably attach the two devices (304, 308). As another example, an air mover unit (308) may attach to a modular processing unit (304) via the material properties of some intermediary fixing means (e.g., adhesive tape, hook-and-loop fasteners, etc.) affixed to one or more surface(s) of the air mover unit (308) and/or modular processing unit (304). One of ordinary skill in the art, having the benefit of this detailed description, would appreciate that any fixing means suitable to attach two physical objects may be utilized to affix an air mover unit (308) to a modular processing unit (304).
In one or more embodiments of the invention, an air mover unit (e.g., air mover unit (308)) includes an air mover (312) and an air mover holder (314). In one embodiment of the invention, an air mover unit (308) (and the components thereof) is used to control, generate, or otherwise manage the flow of gaseous matter within the modular processing unit (304). More detail regarding the description of an air mover unit (308), air mover (312), and air mover holder (314) is provided in the description of
While
In one or more embodiments of the invention, an air mover (e.g., air mover (412)) is used to control, generate, or otherwise manage the flow of gaseous matter within a volume. For example, an air mover (412) may be used to generate a flow of surrounding gaseous matter through the volume of a device (e.g., a modular processing unit) that is unoccupied by solid matter. That is, an air mover (412) can direct and/or generate the flow of gaseous matter across one or more surface(s) of solid matter that is surrounded by that gaseous matter. Lastly, an air mover may force gaseous matter across the surface of solid matter by either sucking-in or blowing-out that gaseous matter. One of ordinary skill in the art, having the benefit of this detailed description, would appreciate the basic principles and operation of an air mover (e.g., air mover (412)).
Accordingly, in one embodiment of the invention, an air mover (412) may be used to force the convection (i.e., thermal exchange via surrounding fluidic matter) on one or more devices thereby expediting the rate at which that device is brought to an equilibrium temperature. One of ordinary skill in the art, having the benefit of this detailed description, would appreciate the process of expediting thermal exchange via the use of an air mover (e.g., air mover (412)).
Examples of an air mover (412) include a fan, a valve to control flow between two gaseous volumes of differing pressure, and/or any other means for controlling, generating, or otherwise managing the flow of gaseous matter. As shown in
In one embodiment of the invention, an air mover (412) uses electrical power (e.g., “power”) to operate one or more components to manage the flow of gaseous matter. For example, a fan may use a direct current (DC) motor operatively connected to the blades of the fan to generate a rotational motion. Similarly, a valve may utilize an electrically powered solenoid to control gaseous flow between two volumes of differing pressure. In one embodiment of the invention, power may be provided to the air mover (412) via a conductive operative connection (not shown) (via e.g., metallic contacts and/or wire(s) terminated with a plug and socket) with the air mover holder (414). Alternatively, power may be provided to the air mover (412) via a conductive operative connection with the modular processing unit (not shown).
In one or more embodiments of the invention, an air mover (412) may be designed and/or designed to operate such that the air mover (412) can only control, generate, or otherwise manage the flow of gaseous matter in one direction. For example, the blades of a fan may be contoured to more efficiently ‘push’ gaseous matter when the blades are rotated in a particular direction, thereby forcing gaseous flow in that one direction. That is, although it may be possible to ‘reverse’ the direction of the fan by reversing the polarity of the DC motor that rotates the blades, those blades (when spun in the opposite direction) would not be as efficient at controlling the flow of gaseous matter. Accordingly, ‘reversing an air mover (412)’ may include physically reversing the air mover (412) (e.g., rotating, flipping, etc.), independently of other components, to align the one direction (the air mover (412) is designed to operate at) with the gaseous flow direction of a larger system.
In one or more embodiments of the invention, an air mover holder (e.g., air mover holder (414)) is a physical device to which the air mover (412) may be affixed. In one embodiment of the invention, an air mover holder (414) is a solid bracket that removably affixes to both an air mover (412) and a modular processing unit (not shown) (as discussed in the description of
In one or more embodiments of the invention, an air mover holder (414) provides a conductive operative connection to the air mover (412) to provide the air mover (412) electrical power to operate. In one embodiment of the invention, the air mover holder (414) may be provided power via one or more conductive operative connections with the modular processing unit (not shown) in order to provide power to the air mover (412).
In one or more embodiments of the invention, an air mover (e.g., air mover (412)) may be detached from an air mover holder (e.g., air mover holder (414)), reversed, and removably re-attached to an air mover holder (e.g., air mover holder (414)) as depicted in
As shown in
Further, in one embodiment of the invention, both sides of an air mover (412) that are normal to the direction of gaseous flow are constructed to include all of the same mounting and/or fixing capabilities. Accordingly, after reversal, the air mover (412) may be reattached to the air mover holder (414) in the same manner as mounted prior to reversal.
In one or more embodiments of the invention—after the air mover (412) is detached, reversed, and re-attached—the air mover holder (414) may be attached, or re-attached, to a modular processing unit (not shown). Further, in one embodiment of the invention, an air mover (412) may be detached, reversed, and re-attached to an air mover holder (414) while the air mover holder remains attached to a modular processing unit (not shown).
Accordingly, by reversing the orientation of the air mover (412), the modular processing unit may be installed in an orientation that matches the gaseous flow already existing in the modular compute unit.
While
In one or more embodiments of the invention, an air mover unit (e.g., air mover unit (508)) is substantially similar to the air mover unit discussed in the description of
In one or more embodiments of the invention, one or more electronic components (e.g., electronic components (520)) are electrically powered and/or operated circuitry. In one embodiment of the invention, electronic components (520) are operatively connected to other components of the modular processing unit (504), the modular compute unit (not shown), and/or the rack (not shown). Although not shown in
In one or more embodiments of the invention, one or more electronic components (520) may generate heat. Further, in one embodiment of the invention, one or more electronic components (520) may be less efficient at hotter temperatures and therefore, it may be preferable to maintain one or more electronic components (520) at comparatively colder temperatures via forced convection of colder surrounding gaseous matter (as described in the discussion of
Non-limiting examples of one or more electronic components (520) include integrated circuit storage devices (e.g., solid-state drive (SSD), M.2, Non-Volatile Memory Express (NVMe), flash memory, random access memory (RAM), dynamic RAM (DRAM), resistive RAM (ReRAM), etc.), processors, and other integrated circuits.
In one or more embodiments of the invention, narrowing walls (e.g., side narrowing wall A (516), side narrowing wall B (518), top narrowing wall (522), bottom narrowing wall (524)) may be constructed on the interior of the modular processing unit (504). In one embodiment of the invention, narrowing walls (516, 518, 522, 524) direct the flow of gaseous matter (caused by an air mover of air mover unit (508)) into a constricted section (528) (i.e., a smaller cross-section of the open volume). Thus, assuming a constant mass rate flow through the modular processing unit (504), the gaseous matter that flows through the constricted section (528) passes through at a faster velocity matter than if the narrowing walls (516, 518, 522, 524) were not present to form the constricted section (528).
As discussed in the description of one or more electronic component(s) (520), it may be preferable to maintain one or more electronic components (520) at relatively cooler temperatures via forced convection (as described in the discussion of
While
In Step 600, one or more user(s) (e.g., a robotic arm under the control of a person, a system administrator, and/or an installer) identifies a desired location and orientation to install a modular processing unit in a modular compute unit. In one embodiment of the invention, a modular processing unit is installed such that the air mover unit of the modular processing unit is disposed against an exterior surface of the modular compute unit. Further, in one embodiment of the invention, the air mover unit is install disposed against a “front” or back” of a modular compute unit (i.e., where the vents of the
In Step 602, the direction of gaseous flow existing in the modular compute unit is identified. In one or more embodiments of the invention, the modular compute unit may already include one or more air movers and/or hardware components that include an air mover. As the already-existing air movers are oriented to guide (and/or force, direct, manage, etc.) gaseous matters to flow in a certain direction, a predetermined gaseous flow direction will already exist within the modular compute unit.
In Step 604, a determination is made as to whether the air mover of the modular processing unit, if installed in the desired orientation (as determined in Step 600), is oriented to guide gaseous matter in the same direction as already existing within the modular compute unit (or, if not, require reversal). In one embodiment of the invention, the modular processing unit is provided to a user with the air mover installed on the modular processing unit. Accordingly, the installed direction of the air mover may not match the already-existing gaseous flow direction within the modular compute unit and will therefore need to be reversed prior to the installation of the modular processing unit.
If the air mover is oriented to guide gaseous matter in the same direction as already existing within the modular compute unit (604-NO), the process proceeds to Step 616. Alternatively, if the air mover is not oriented to guide gaseous matter in the same direction as already existing within the modular compute unit (604-YES), the process proceeds to Step 606.
In Step 606, the air mover unit is detached from the modular processing unit. In one or more embodiments of the invention, the air mover unit may be detached from the modular processing unit by reversing the method(s) used to initially attach the air mover unit and modular processing unit (e.g., unscrewing, unlatching, unclipping, etc.).
In Step 608, the air mover is detached from the air mover holder. In one or more embodiments of the invention, the air mover may be detached from the air mover holder by reversing the method(s) used to initially attach the air mover and air mover holder (e.g., unscrewing, unlatching, unclipping, etc.). In one embodiment of the invention, it may be necessary to first detach the air mover unit from the modular processing unit prior to detaching the air mover from the air mover holder. Alternatively, in one embodiment of the invention, it may be possible to detach the air mover from the air mover holder without first detaching the air mover unit from the modular processing unit.
In Step 610, the air mover is reversed. In one or more embodiments of the invention, reversing the air mover includes rotating the air mover 180° about an axis orthogonal to the direction of gaseous flow. Accordingly, once reversed, the air mover will guide (and/or force, direct, manage, etc.) gaseous matter in a direction 180° opposite to the prior direction.
In Step 612, the air mover is re-attached to the air mover holder. In one or more embodiments of the invention, the air mover may be re-attached to the air mover holder by reversing the method(s) used to detach the air mover and air mover holder (e.g., those of Step 608). In one embodiment of the invention, it may be possible to re-attach the air mover to the air mover holder while the air mover holder is still attached to the modular processing unit (in the event that the air mover unit was not detached from the modular processing unit (Step 606)).
In Step 614, the air mover unit is re-attached to the modular processing unit. In one or more embodiments of the invention, the air mover unit may be re-attached to the modular processing unit by reversing the method(s) used to detach the air mover unit and modular processing unit (e.g., those of Step 606).
In Step 616, the modular processing unit is installed in the modular compute unit in the desired orientation. In one or more embodiments of the invention, as the air mover either (i) did not need to be reversed (Step 604-NO), or (ii) needed to be reversed (604-YES) and was subsequently reversed (Steps 606-614), the modular processing unit may be installed such that components thereof (i.e., the air mover) are oriented consistent with the gaseous flow direction of the modular compute unit.
In one embodiment of the invention, installing the modular processing unit in the modular compute unit includes affixing the modular processing unit to the chassis of the modular compute unit via one or means for attaching (as discussed in the description of
While one or more embodiments have been described herein with respect to a limited number of embodiments and examples, one of ordinary skill in the art, having the benefit of this detailed description, would appreciate that other embodiments can be devised which do not depart from the scope of the embodiments disclosed herein. Accordingly, the scope should be limited only by the attached claims.