KR101141594B1 - Balance keeping crane and vessel with the crane - Google Patents

Abstract

The present invention relates to a crane capable of maintaining an equilibrium regardless of the fluctuation of the ship by using the concept of zero moment, and a ship capable of unloading cargo at sea off the land by mounting it. The present invention includes an upper body including a horizontal structure in which a trolley is installed to be transported in a transverse direction, a lower body connected to a support joint at a point where the moment of the upper body becomes zero, and supporting the upper body; It is provided on the lower body and provides a crane and a ship equipped with the auxiliary support that can be adjusted in the vertical height of the horizontal structure supporting the horizontal structure at one end of the horizontal structure. The present invention enables precise balance control because the balance is maintained without applying a large force to the hydraulic cylinder through the support by the zero moment point.

Mobile harbor, mobile harbor, crane, equilibrium, zero moment

Description

Balancing Crane and Vessel with It {BALANCE KEEPING CRANE AND VESSEL WITH THE CRANE}

The present invention relates to a crane, and more particularly to a crane capable of maintaining equilibrium regardless of the fluctuation of the ship by using the concept of zero moment, and a ship capable of unloading cargo at sea offshore by mounting it .

Maritime transportation using ships as a means of moving goods remotely takes up a large part of international trade because it uses less energy and lowers transportation costs compared to other means of transportation.

In recent years, in marine transportation such as container ships, large-scale ships are used to improve the efficiency of transportation, which is intended to secure the economics of transportation by increasing the transportation volume of the vessel. Accordingly, more and more ports are required to have mooring and unloading facilities for docking large vessels.

However, harbors that can berth large container ships are limited at home and abroad, and the construction of such ports requires a lot of expenses due to dredging to maintain the necessary port depth, as well as a large place. In addition, due to the construction of a large port has a lot of influence on the surrounding environment, such as causing a traffic jam or destruction of the coastal environment, there are many restrictions on the construction of a large port.

Accordingly, the invention relates to a mobile port (mobile harbor) capable of loading and unloading cargo without anchoring a large vessel to the inner wall of the port and anchored at sea off the land, and a method for transferring the cargo using the patent ( Registration number 10-0895604).

1 shows a schematic view of the mobile port shown in the patent, the mobile port 10 can be carried out by the crane 20, the loading operation, Figure 1 (a) is a mobile port (10) And the unloading between the large container ship 30, and FIG. 1 (b) shows the unloading between the mobile harbor 10 and the pier 40. FIG.

The mobile port 10 includes a platform having a space for loading cargo to be loaded or unloaded, a facility for loading and unloading cargo between the vessel and the platform, and a transport facility for transferring cargo on the platform. A cargo transfer device, a positioning device for acquiring information regarding the position of the platform, a buffer connecting device such that the platform remains connected without colliding with the ship during loading and unloading of the cargo, and the like. do.

Loading and unloading of cargo is the work of moving several tons or tens of tons of cargo, so it is urgently required to maintain the equilibrium of the ship and the crane mounted as a mobile port, but the effects of wind, blue, or tidal current at sea As the rocking of the ship is indispensable, there is a need for a crane having a structure capable of maintaining equilibrium while the ship is working at sea despite the rocking.

The present invention has been made in consideration of the above problems, the present invention is to maintain the horizontal position and vertical position of the crane in response to the rolling and pitching or heaving motion of the ship to enable a stable cargo unloading with other ships An object is to provide a crane and a ship equipped with the same.

The present invention includes an upper body including a horizontal structure in which a trolley is installed to be transported in a transverse direction, a lower body connected to a support joint at a point where the moment of the upper body becomes zero, and supporting the upper body; It is provided on the lower body provides a crane comprising an auxiliary support capable of vertical height adjustment for supporting the horizontal structure at the horizontal end of the horizontal structure.

The support joint may be installed at a point where two or more moments of the upper body become zero, and the auxiliary support may be provided in plural to allow the multi-degree of freedom of the upper body. By adjusting the height of the auxiliary support may further include a control unit for controlling the posture of the upper body in response to the swing of the lower body. The control unit may control a horizontal state of the horizontal structure or a vertical position of the trolley in response to any one or more motions of the lower body, such as hebbing, rolling, or pitching.

The lower body may include a first pillar installed at a point where the moment of the upper body becomes zero, a second pillar installed at a point supporting the auxiliary support at a distance from the first pillar, and the first pillar. And a base supporting the second pillar. Furthermore, the base may include a first base and a second base that support and move the first pillar and the second pillar, respectively. The first pillar and the second pillar may be provided with a height adjustment portion capable of adjusting the height in the vertical direction. Furthermore, the first column is formed in plural and connected through a first horizontal beam, the support joint is installed in the first horizontal beam, and the second column is formed in plural and connected through a second horizontal beam. The auxiliary support may be installed on the second horizontal beam. The first horizontal beam may be positioned above the horizontal structure, and the trolley may be installed below the horizontal structure to be freely transported along the horizontal structure.

Alternatively, the lower body may support a longitudinally movable first base supporting the upper body at a point where the moment of the upper body becomes zero, and support the auxiliary support at a distance from the first base and move longitudinally. It may include a second base. Furthermore, the lower body may include first and second horizontal beams on which the first and second bases are respectively supported, and first and second pillars respectively supporting the first and second horizontal beams.

Meanwhile, the support joint may be a universal joint or a spherical joint. The upper body may be vibration-insulated and supported by a vibration insulator having a spring-damper structure. Next, the upper body may have a balance such that the lateral moment is maintained at zero. The balance may be transversely movable along the horizontal structure. The horizontal structure may be formed as a combination of multi-stage beams to allow entry and exit in multiple stages. Further, the upper body is connected to the other end of the horizontal structure and the upright beams standing upright in the upper portion of the horizontal structure in accordance with the protruding of the multi-stage beams, from one end of the horizontal structure through one end of the upright beams. It may include a rope for supporting the multi-stage beam.

The present invention provides a ship or offshore structure having the crane described above. Here, the lower body may include a first pillar installed at a point where the moment of the upper body becomes zero, a second pillar installed at a point supporting the auxiliary support at a distance from the first pillar, and the first pillar. It may include a pillar and a base for supporting the second pillar. The base may include a first base and a second base that support and move the first pillar and the second pillar, respectively. Furthermore, the first and second bases are provided with wheels, and the wheels are movable on rails provided on both side surfaces of the ship, but may not be separated from the rails.

According to the crane according to the present invention, the horizontal state of the horizontal structure or the vertical position of the trolley is maintained in response to the swinging of the lower body, thereby enabling a stable unloading operation. Furthermore, according to the ship equipped with a crane according to the present invention to maintain the equilibrium of the crane in response to the movement of the ship, such as pitching, rolling or hebbing, it is possible to unload a stable cargo with other vessels.

In addition, since the crane according to the present invention can maintain the equilibrium without applying a large force to the hydraulic cylinder through the support by the zero moment point, it is possible to control the precise balance of the crane.

Therefore, the ship according to the present invention can efficiently handle the cargo transportation of the large vessels requiring deep water depth and can function as a mobile port, which will contribute to strengthening future port system competitiveness.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that detailed descriptions of related well-known technologies or functions may obscure the gist of the present invention, the detailed description thereof will be omitted.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

DETAILED DESCRIPTION Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings, and in the following description with reference to the accompanying drawings, the same or corresponding components will be given the same reference numerals and redundant description thereof will be omitted. do.

2 is a schematic diagram showing the concept of equilibrium maintenance using zero moment points.

Referring to FIG. 2A, an upper body 70 is installed on the lower body 60, where the upper body 70 is supported at a point where the weight is balanced and the moment becomes zero. A pivotable body joint 65 connects the lower body 60 and the upper body 70, and both ends of the upper body 70 are assisted by a body support 75, such as a hydraulic cylinder. Here, the body support 75 does not necessarily need to be at both ends, but in the case of support at both ends, more stable balance can be maintained. In addition, a spring and a damper (not shown) may be attached in parallel with the body support 75 to help balance the upper body 70.

 As shown in FIG. 2B, a body support 75 such as a hydraulic cylinder may be installed in another direction to maintain the equilibrium of the upper body 70 in three dimensions. At this time, the body joint 65 will be composed of a joint capable of turning in two directions, such as a universal joint.

In addition, by adding a vibration insulator 68 including a spring or an air cushion between the upper body 70 and the lower body 60, by vibrating the upper body 70 from vibrations of high frequency, the control is more easily controlled. You may. In addition, by installing a spring-damper structure (not shown) in parallel with the body support 75, the control force of the body support 75 may be reduced. The spring-damper structure can be provided using various methods such as a rigid spring or an air cushion or rubber.

Although the upper body 70 is shown in the form of an inverted triangle or an inverted pyramid for the sake of simplicity of the drawing, the upper body 70 may be applied regardless of its shape as long as it is supported at a point where the moment becomes zero.

Since the upper body 70 is supported by most of the weight through the body joint 65 and less force at both ends, it becomes possible to control the movement of the upper body 70 without applying a large force to the hydraulic cylinder. Therefore, despite the fluctuation of the lower body 60, the upper body 70 is able to maintain a precise level.

The concept of the zero moment point was proposed to implement the gait of the robot around 1984, and there have been many studies since. This relates to a dynamic system and has been used as a concept to define the relationship to the static ground, which is different from the upper body control in the situation where the lower body is moving as in the present invention. Therefore, although it is named as a zero moment point concept for convenience, it is actually a central support concept and should be regarded as an application different from the robot application concept so far. For example, the lower body 60 of FIG. 2 is a vessel such as a warship, and the upper body 70 may be applied when the system is to be motionless, such as a precision device such as a radar or projectile, the application target of which is If the invention uses the principles presented, all of them can be applied. The present invention seeks to apply this zero moment point concept (or center support concept) to a crane installed on a ship.

Figure 3 is a perspective view showing the structure of the balancing crane according to an embodiment of the present invention. 4 is a side view illustrating the structure of the balancing crane of FIG. 3. 5 is a cross-sectional view showing the structure of the upper body of the balancing crane of FIG. 6 is a side view showing a state in which the equilibrium crane of Figure 3 is modified. Here, the coordinates are defined as the longitudinal direction in the x direction and the transverse direction in the y direction.

Equilibrium maintenance crane 200 according to an embodiment of the present invention, the upper body including a horizontal structure 230, the trolley 238 is installed to be transported in the transverse direction, the point where the moment of the upper body is zero The crane 200 including the lower body for supporting the upper body, and the auxiliary support 222 is installed on the lower body to support the horizontal structure 230 in the horizontal one end of the horizontal structure 230 and the height can be adjusted in the vertical direction ). The upper body and the lower body are connected by the support joint 217.

The support joint 217 corresponds to the body joint 65 installed at the zero moment point described above, and is installed at a point where both the transverse and longitudinal moments become zero. The auxiliary support 222 may correspond to a body support 75 such as the hydraulic cylinder described above, and may be installed in plural to allow six degrees of freedom of the upper body. The crane 200 may include a controller (not shown) that controls six degrees of freedom of the upper body by adjusting the height of the auxiliary support 222. Or by controlling the height of the auxiliary support 222 may include a controller (not shown) for controlling the posture or position of the upper body in response to the swing of the lower body. Here, the controller may control the horizontal state of the horizontal structure 230 or the vertical position of the trolley 238 in response to any one or more motions of the lower body, the hebbing, rolling or pitching.

Auxiliary support 222 may be configured to include a hydraulic cylinder. The support joint 217 is formed in a pivotable structure so that the horizontal structure 230 can be inclined in the longitudinal or transverse direction. For example, the support joint 217 may be configured as a universal joint or a spherical joint. The upper body may be vibration-insulated and supported by a vibration insulator (not shown) having a spring-damper structure. The spring-damper structure can be manufactured using materials such as springs, air cushions, and rubbers with high rigidity, and mainly serves to isolate high frequency vibrations.

The upper body may have a balance 236 such that the lateral moment is maintained at zero. The balance 236 may be moved or detached along the horizontal structure 230 in a direction to compensate for the change in the weight applied to the horizontal structure 230, such as the transportation of the trolley 238 and the load of the cargo, so that the lateral moment is zero. To be derived.

Referring to FIGS. 3 and 4, the structure of the lower body will be described in more detail. The lower body may be spaced apart from the first pillar 210 and the first pillar 210 installed at a point where the moment of the upper body becomes zero. And a second base 220 installed at a point supporting the auxiliary support 222, and a lower base supporting the first pillar 210 and the second pillar 220. The base may include a first base 214 and a second base 224 that support and move the first pillar 210 and the second pillar 220, respectively. The first and second bases 114 and 124 may be provided with wheels (not shown) for movement. Each of the first and second pillars 210 and 220 may be provided with a height adjusting unit (not shown) capable of adjusting the height in the vertical direction. The first pillar 210 and the second pillar 220 may be formed in plural and may be connected through the first horizontal beam 219 and the second horizontal beam 229, respectively.

3 and 5, a support joint 217 is installed on the first horizontal beam 219, and an auxiliary support 222 is installed on the second horizontal beam 229. The first horizontal beam 219 is positioned above the horizontal structure 230, and the trolley 238 is installed below the horizontal structure 230 to be freely transported along the horizontal structure 230. In addition, the reinforcement beam 239 may be installed to ensure stability of the crane 200 structure.

To describe the structure of the upper body in more detail, the horizontal structure 230 of the upper body as a combination of the multi-stage beams 231 may be formed to be able to enter and exit in multiple stages. Furthermore, the upper body has an upright beam 240 that stands upright from the top of the horizontal structure 230 in accordance with the protruding of the multi-stage beam 231, the upright beam 240 is rotatable about the hinge 242, It can be secured in two states when fully folded toward winch 246 and when perpendicular to horizontal structure 230. In addition, the upper body is connected to the winch 246 installed at the other end of the horizontal structure 230 through one end of the upright beam 240 from one end of the horizontal structure 230 to support the multi-stage beam 231 protruding ( 244).

According to the crane 200 according to the present invention, a stable unloading operation is possible by controlling the horizontal state of the horizontal structure 230 and the vertical position of the trolley 238 in response to the swing of the base. In particular, since it is possible to maintain the equilibrium without applying a large force to the hydraulic cylinder constituting the auxiliary support 222 through the support by the support joint 217 at the zero moment point, it is possible to precisely control the balance of the crane.

Figure 7 is a block diagram showing the structure of a ship equipped with a balancing crane according to an embodiment of the present invention. The present invention provides a ship 250 or offshore structure provided with the crane 200 described above. Here, the longitudinal direction is the longitudinal direction of the vessel 250, and the transverse direction is both side directions of the vessel 250.

The upper portion of the vessel 250 is provided with a platform 252 on which cargo can be loaded. The first and second bases 214 and 224 are respectively installed on both sides of the ship 250 in the transverse direction to be movable in the longitudinal direction. Rails 254 may be provided at both sides of the vessel 250 so that wheels (not shown) provided in the first and second bases 214 and 224 may move along the rails 254. Of course, the distance between the first base 214 and the second base 224 may be smaller than the width of the vessel 250. The driver 256 may be implemented in various ways, such as a motor (not shown) providing power for moving the crane 200 and a wire transfer system (not shown) using a rope and a winch. For added safety, the wheels can be designed to be structured as a cart or sliding office desk drawer that is transported on rails 254 so that they can move on rails 254 but are not separated.

Referring to FIG. 6, the vessel 250 according to an embodiment of the present invention may fold the upright beam 240 of the upper body to lower its height. In addition, the height of the first and second pillars 210 and 220 may be reduced by using a height adjusting part (not shown) of the lower body. Therefore, according to the present invention can lower the height of the crane during navigation to reduce the resistance during navigation and to facilitate the passage of the bridge.

8 is a configuration diagram showing a structure of a balance maintenance crane according to another embodiment of the present invention. 9 is a configuration diagram showing a state in which the balance maintenance crane of FIG. 8 is viewed from another side.

According to another embodiment of the present invention, the lower body supports the upper body at a point where the moment of the upper body becomes zero, and is spaced apart from the longitudinally movable first base 214 and the first base 214. It may include a second base 224 that supports the secondary support 222 and is longitudinally movable. Furthermore, the lower body may include first and second horizontal beams 219 and 229 on which the first and second bases 214 and 224 are supported, and first and second horizontal beams 219 and 229, respectively. It may include the first and second pillars (210, 220). Other components not described herein may be implemented with a structure and a function similar to those of the embodiment shown in FIG. 3. According to the embodiment shown in FIG. 8, since the first and second bases 214, 224 are movable along the first and second horizontal beams 219, 229, respectively, the lower body does not move and the upper body does not move. Unloading work is possible while moving the bay.

Hereinafter, a method for operating a balance crane and a ship according to an embodiment of the present invention will be described in detail. FIG. 10 shows a state in which a ship according to an embodiment of the present invention performs an unloading operation between other container ships. Drawing.

As shown, the side of the vessel 250 is provided with a crane 200 according to an embodiment of the present invention and the side of the container ship (S) docked, the crane 200 installed on the vessel 250 container ship ( It extends long in the direction S) to carry out the unloading of the container, that is, the cargo (C). The trolley 238 loads the cargo C and moves along the horizontal structure 230, and the balance 136 keeps the moment of the upper body zero.

The vessel 250 is swung due to the influence of wind, blue, or algae in the sea. The swing may include a hebbing, rolling, or pitching, and in spite of the swing, the cargo C may be smoothly unloaded only when the crane 200 or the absolute horizontal position of the trolley 238 is maintained. For example, even if there is a pitching of the vessel 250, the crane 200 is intended to avoid pitching. The controller may detect the pitching of the vessel 250 to adjust the hydraulic pressure of the hydraulic cylinder constituting the auxiliary support 222 to maintain the horizontal structure 230 horizontal. Similarly, the auxiliary support 222 is controlled by the action of the control unit so that the horizontal state of the horizontal structure 230 is maintained in response to the rolling motion of the vessel 250, or the trolley 238 in response to the heaving movement of the vessel 250 Height can be controlled to maintain the vertical position of

On the other hand, the container ship S, which is the object of unloading at sea, also fluctuates under the influence of blue and wind. At this time, when the trolley 238 lifts or lowers the container, that is, the cargo (C) from the container ship (S) that is the object of unloading at sea, the relative support of the container ship (S) and the trolley (238) to the auxiliary support ( 222 can be removed by adjusting, even when lifting or lowering the cargo (C) from the vessel 250 by adjusting the auxiliary support 222, to remove the relative movement of the trolley 238 and the vessel 250 Can be.

According to the ship equipped with a crane according to an embodiment of the present invention, the horizontal and vertical position of the crane is controlled in response to the movement of the ship, such as pitching, rolling or heaving, so that stable cargo unloading with other container ships is possible. do. The vessel according to the present invention can efficiently handle the cargo transportation of container ships requiring deep water depth and can function as a mobile port, thereby contributing to strengthening future port system competitiveness.

As mentioned above, although specific embodiment of this invention was described, this is only an illustration and this invention is not limited to this, It should be interpreted that it has the broadest range based on the basic idea disclosed in this specification. Those skilled in the art can change the material, size, etc. of each component according to the application field, it is possible to implement a pattern of the shape not shown by combining or replacing the disclosed embodiments, but this is also not departing from the scope of the present invention. In addition, those skilled in the art can easily change or modify the disclosed embodiments based on the present specification, it is apparent that such changes or modifications are included in the scope of the present invention.

1 is a view showing a schematic view of a mobile port shown in the prior patent.

2 is a schematic diagram showing the concept of equilibrium maintenance using zero moment points.

Figure 3 is a perspective view showing the structure of the balancing crane according to an embodiment of the present invention.

4 is a side view illustrating the structure of the balancing crane of FIG. 3.

5 is a cross-sectional view showing the structure of the upper body of the balancing crane of FIG.

6 is a side view showing a state in which the equilibrium crane of Figure 3 is modified.

FIG. 7 is a configuration diagram showing the structure of a ship equipped with the equilibrium crane of FIG. 3.

8 is a configuration diagram showing a structure of a balance maintenance crane according to another embodiment of the present invention.

9 is a configuration diagram showing a state in which the balance maintaining crane of FIG. 8 is viewed from another direction.

10 is a view showing a state in which the vessel according to an embodiment of the present invention performs the unloading operation between the other vessels.

<Description of main parts of drawing>

60: lower body 65: body joint

68: vibration insulation 70: upper body

75: body support

200: crane 210, 220: first and second pillars

214, 224: first and second base

217: support joints 219 and 229: first and second horizontal beams

222: auxiliary support

230: horizontal structure 231: multistage beam

236 balance 238 trolley

239: reinforcement beam

240: upright beam 242: hinge

244: rope 246: winch

250: ship 252: platform

254: rail 256: drive unit

C: Cargo S: Container Ship

Claims (22)

An upper body including a horizontal structure on which the trolley is installed to be traversed transversely; A lower body connected to the support joint and supporting the upper body at a point where the moment of the upper body becomes zero; An auxiliary support which is installed on the lower body and capable of adjusting a height in a vertical direction to support the horizontal structure at one end in the horizontal direction of the horizontal structure; Including crane. The method of claim 1, The support joint is installed at a point where the moment in two or more directions of the upper body becomes zero, The auxiliary support is a plurality of cranes are installed to enable the multi-degree of freedom movement of the upper body. The method of claim 1, And a controller configured to control the posture of the upper body in response to the swing of the lower body by adjusting the height of the auxiliary support. The method of claim 3, The control unit, And a crane for controlling the horizontal state of the horizontal structure or the vertical position of the trolley in response to any one or more motions of the lower body such as hebbing, rolling or pitching. The method according to any one of claims 1 to 4, The lower body, A first pillar installed at a point where the moment of the upper body becomes zero; A second column installed at a point supporting the auxiliary support at intervals from the first column; A lower base supporting the first pillar and the second pillar Including crane. The method of claim 5, And the base includes a first base and a second base that are movable and support the first pillar and the second pillar, respectively. The method of claim 6, The first pillar and the second pillar, Each crane is provided with a height adjustment unit capable of adjusting the vertical height. The method of claim 5, The first pillar is formed in plurality and connected through a first horizontal beam, the support joint is installed on the first horizontal beam, The second pillar is formed of a plurality is connected through a second horizontal beam, the second horizontal beam crane is provided with the auxiliary support. The method of claim 8, The first horizontal beam is located above the horizontal structure, The trolley is installed on the lower portion of the horizontal structure crane freely moveable along the horizontal structure. The method according to any one of claims 1 to 4, The lower body, A first base longitudinally movable and supporting the upper body at a point where the moment of the upper body becomes zero; A second base that is longitudinally movable and supports the auxiliary support at intervals from the first base; Including crane. The method of claim 10, The lower body, First and second horizontal beams on which the first and second bases are respectively supported; First and second pillars supporting the first and second horizontal beams, respectively. Including crane. The method according to any one of claims 1 to 4, The support joint is a universal joint or spherical joint. The method according to any one of claims 1 to 4, The upper body is vibration-insulated and supported by a vibration insulator having a spring-damper structure. The method according to any one of claims 1 to 4, The upper body has a balance such that the transverse moment is maintained at zero. The method of claim 14, The balance is transversely movable crane along the horizontal structure. The method according to any one of claims 1 to 4, The horizontal structure is a crane which is formed to be able to enter and exit from one side in a multi-stage combination of beams. The method of claim 16, The upper body, An upright beam standing upright at the top of the horizontal structure according to the protruding of the multi-stage beam, A rope for supporting the multi-stage beam that protrudes from one end of the horizontal structure through one end of the upright beam and protrudes from the other end of the horizontal structure. Including crane. Ship provided with the crane of any one of Claims 1-4. The method of claim 18, The lower body, A first pillar installed at a point where the moment of the upper body becomes zero; A second column installed at a point supporting the auxiliary support at intervals from the first column; A base supporting the first pillar and the second pillar A ship having a crane comprising. The method of claim 19, The base includes a crane supporting the first and second pillars, respectively, the crane comprising a movable first base and a second base. 21. The method of claim 20, The first and second bases have wheels, The wheel is provided with a crane movable on a rail provided on both sides of the ship in the transverse direction, but not separated from the rail. Offshore structure provided with the crane of any one of Claims 1-4.

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