JP2019184482A - Hole wall observation system - Google Patents

Abstract

To provide a hole wall observation system that can easily perform hole wall observation using an inexpensive camera.SOLUTION: A system includes a shooting truck 1 equipped with a spherical camera 11 for photographing an inner wall of a boring hole; and a hole wall deploying figure generator 2 for generating a hole wall deployment figure Hfrom the photographed data, and the hole wall expansion figure generating device 2 is equipped with a partial deployment figure generating unit 32 generating a 360 degree panoramic image in which a peripheral whole area is photographed from the photographed data acquired by an image acquisition unit 31 for every predetermined period of time as a partial development figure H; a feature point extraction unit 33 for generating a feature point monitor data Dextracting the feature point from the partial development figure H; a feature point matching unit 34 for matching the feature point monitor data Dof the partial development figure Hbefore and after the shooting time; and the partial development figure connecting unit 35 for connecting the partial development figure Hbefore and after the shooting time based on the axial and circumferential conversion distance and direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hole wall observation system that observes a hole wall in a borehole.

  After performing non-core boring (drilling logging) or after drilling the ground anchor hole, observe the hole wall in the drilling hole to determine the location and cause of the weak part of the natural ground (crack, weathering, fault, etc.) Can be specified (see, for example, Patent Document 1).

  Conventionally, the wall observation is performed by an imaging device called a borehole television (hereinafter referred to as BHTV). BHTV images a hole wall surface by placing a camera in the boring hole axial direction and installing a conical mirror at the tip. The photographing position in the borehole is measured by a distance meter, and a series of hole wall development views are generated by arranging the hole wall images for each photographing position.

  The position and cause of the weak part of the natural ground can be grasped quantitatively (crack width and interval, strike slope) by the hole wall development. Moreover, it is possible to comprehensively grasp the situation in the hole by arranging the hole wall development diagrams for each depth.

Utility Model Registration No. 3119012

  However, BHTV is very expensive, and special care must be taken when handling conical mirrors. Further, when observing a hole wall of a horizontal borehole, there is a high risk that the hole wall will collapse and the photographing apparatus will not come out, and a cost corresponding to that risk will be generated. Furthermore, since it is necessary to perform precise distance measurement while photographing, preparation and cost are required.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a hole wall observation system capable of solving the above-described problems and easily performing hole wall observation using an inexpensive camera. .

A hole wall observation system according to the present invention includes a photographing carriage equipped with a camera for photographing an inner wall of a boring hole, and a hole wall development drawing generating device for generating a hole wall development figure from photographing data photographed by the photographing carriage. Then, the hole wall development view generating device, the image acquisition unit for acquiring the imaging data every predetermined time, and the imaging data acquired by the image acquisition unit, the axial direction of the borehole is a predetermined length, A partial development view generation unit that generates a 360-degree panoramic image showing the entire circumferential direction as a partial development view, and feature point monitor data obtained by extracting feature points from the partial development view generated by the partial development view generation unit The feature point extraction unit is matched with the feature point monitor data of the partial development view whose shooting time is before and after, and the conversion distance and conversion direction in the axial direction and the circumferential direction at the time of matching are determined. The hole is formed by connecting the feature point matching unit to be calculated, and the partial development view in which the photographing time is changed based on the axial direction and circumferential direction conversion distance and conversion direction calculated by the feature point matching unit. And a partial development view connecting section for generating a wall development view.
Furthermore, in the hole wall observation system according to the present invention, when the hole wall development view generation operation is performed by the hole wall development view generation device after the photographing by the camera, the feature point matching unit is configured so that the photographing time is around. If the feature point monitor data of the partial development view does not match, the partial development view that was photographed later is deleted, and the partial development view that was photographed later is the one that was photographed before You may match with a partial development view.
Furthermore, in the hole wall observation system of the present invention, comprising a warning output unit for outputting a warning,
When the shooting by the camera and the generation operation of the hole wall development view by the hole wall development drawing generation device are performed in parallel, the feature point matching unit If the feature point monitor data does not match, a warning may be output by the warning output unit.
Furthermore, in the hole wall observation system of the present invention, the feature point matching unit deletes the partial development view of the later imaged image if the feature point monitor data of the partial development view whose imaging time is before and after does not match. You may do it.
Furthermore, in the hole wall observation system of the present invention, the camera is an omnidirectional camera including two imaging optical systems that are combined in opposite directions so that their optical axes coincide with each other. The carriage is configured so that the optical axis of the imaging optical system is orthogonal to the central axis of the boring hole, and the distance between the two imaging optical systems and the inner wall of the boring hole is the same on the optical axis. A centralizer for supporting the celestial sphere camera on the central axis of the boring hole may be provided.
Furthermore, in the hole wall observation system of the present invention, the partial development view generation unit is configured such that a circumferential line of the borehole passing through an optical axis of the imaging optical system of the omnidirectional camera is an axial direction of the borehole. You may generate | occur | produce the partial expanded view used as the center line of.
Further, the photographing cart of the present invention is a photographing cart equipped with a camera for photographing the inner wall of the boring hole, and the two cameras combined in opposite directions so that their optical axes coincide with each other as the camera. An omnidirectional camera equipped with an imaging optical system is mounted, the optical axis of the imaging optical system is orthogonal to the central axis of the borehole, and on the optical axes of the two imaging optical systems and the inner wall of the borehole A centralizer is provided for supporting the omnidirectional camera on the central axis of the boring hole so that the distances are the same.

  Advantageous Effects of Invention According to the present invention, partial development views generated from photographing data can be connected without using precise distance measurement results, and hole wall observation can be easily performed using an inexpensive camera. .

It is a sectional side view which shows the structure of embodiment of the hole wall observation system which concerns on this invention. It is a block diagram which shows the structure of the hole wall expanded view production | generation apparatus shown in FIG. It is explanatory drawing for demonstrating the imaging | photography procedure of the inner wall of a boring hole using the imaging cart shown in FIG. It is explanatory drawing for demonstrating operation | movement of the partial expansion view production | generation part and feature point extraction part which are shown in FIG. It is explanatory drawing for demonstrating operation | movement of the feature point matching part shown in FIG. 2, and a partial expanded view connection part.

Next, modes for carrying out the present invention (hereinafter, simply referred to as “embodiments”) will be specifically described with reference to the drawings.
Referring to FIG. 1, the observation system according to the present embodiment refers to an imaging cart 1 equipped with a camera that images the inner wall of a boring hole, and a hole wall deployment that generates a hole wall development view from imaging data captured by the imaging cart 1. It is comprised with the figure production | generation apparatus 2. FIG.

  The photographing carriage 1 is equipped with a omnidirectional camera 11 as a camera for photographing the inner wall of the boring hole, and also includes a front camera 12, an illumination 13, and a centralizer 14.

  The omnidirectional camera 11 is a photographing device capable of photographing all directions in the vertical and horizontal directions. In the present embodiment, the omnidirectional camera 11 includes imaging optical systems 15a and 15b having the same structure including a wide-angle lens having a full angle of view greater than 180 degrees and an imaging sensor such as a CMOS that captures an image by the wide-angle lens. The two combinations, the imaging optical systems 15a and 15b, are combined in opposite directions so that their optical axes coincide. Note that the omnidirectional camera 11 that combines three or more imaging optical systems (for example, an angle of view of 90 degrees × 4) or the entire sky that combines imaging optical systems of different angles of view (for example, an angle of view of 270 degrees + 90 degrees). A spherical camera 11 may be employed.

  The front camera 12 is a normal camera for monitoring the situation in the hole for photographing the front, and a digital camera such as a CMOS camera using a CMOS image sensor can be used.

  The illumination 13 irradiates light to an area captured by the omnidirectional camera 11 and the front camera 12.

  The centralizer 14 has a plurality of arms provided at the tip with wheels that run in the axial direction in contact with the inner wall of the borehole, and the plurality of arms are radiated toward the inner wall of the borehole so as to The celestial camera 11 is supported on the center axis of the borehole. In the omnidirectional camera 11, the centralizer 14 causes the optical axes of the wide-angle lenses in the imaging optical systems 15a and 15b to be orthogonal to the central axis of the borehole, and the inner walls of the wide-angle lenses and the boreholes in the imaging optical systems 15a and 15b. The distances Ra and Rb on the optical axis are the same.

  The hole wall development drawing generation apparatus 2 is an information processing apparatus that operates under program control such as a personal computer. Referring to FIG. 2, the control section 3 and a storage section 4 constituted by storage means such as a hard disk and semiconductor memory. A warning output unit 5 including a voice output device such as a speaker, a warning lamp, and a display device such as a liquid crystal display; and a development view output unit 6 including a display device such as a liquid crystal display and a printing device such as a printer. It has.

  The control unit 3 is an information processing unit such as a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The ROM stores a control program for performing operation control of the hole wall development drawing generating device 2. The control unit 3 reads out the control program stored in the ROM, and develops the control program in the RAM, whereby the image acquisition unit 31, the partial development drawing generation unit 32, the feature point extraction unit 33, and the feature point matching. It functions as the part 34 and the partial development drawing connection part 35.

  The image acquisition unit 31 acquires shooting data for every predetermined time from the omnidirectional camera 11. The image acquisition unit 31 may acquire still images taken every predetermined time by the omnidirectional camera 11 as photographic data, and extract it for each designated number of frames from the moving picture taken by the omnidirectional camera 11. A still image may be acquired as shooting data.

The partial development view generation unit 32 generates partial development views H 1 to _n from the photographing data for each predetermined time acquired by the image acquisition unit 31 and stores them in the storage unit 4. The partial development view generation unit 32 corrects the distortion of the photographing data, partially develops a 360-degree panoramic image in which the axial direction of the borehole is a predetermined length L (for example, L = 4 cm) and the entire circumferential direction of the borehole is copied. It produces _| generates as figure H1- _n , respectively. As shown in FIG. 1, the partial development views H 1 to _n generated by the partial development view generation unit 32 are the circumferential directions of the boreholes passing through the optical axes of the wide-angle lenses in the imaging optical systems 15 a and 15 b of the omnidirectional camera 11. This line is the center line C in the axial direction of the boring hole, and is a range of L / 2 in the front-rear direction around the center line C. Note that the shooting data acquired by the image acquisition unit 31 includes two images respectively captured by the imaging optical systems 15a and 15b of the omnidirectional camera 11, and the partial development view generation unit 32 includes two images. _Are combined to generate partial development views H 1 to _n .

The feature point extraction unit 33 extracts a plurality of “feature points” from the partial development views H 1 to _n generated by the partial development view generation unit 32, and the image coordinates (x, y) of the extracted “feature points”. _Are generated as feature point monitor data D1 to _n and stored in the storage unit 4, respectively.

  The feature point extraction unit 33 extracts cracks on the inner wall of the borehole, change points of the rock quality, and the like as “feature points”. Therefore, since the inner wall of the borehole has many textures such as cracks and rocky change points, “feature points” can be easily extracted.

As a result, partial development views H 1 to _{n for} each predetermined time are generated by the partial development drawing generation unit 32, and feature point monitor data D 1 _{to n for} each of the partial development drawings H 1 to _n by the feature point extraction unit 33. Is generated.

The feature point matching unit 34 uses the feature point matching technique to match the feature point monitor data D1 _{to n} of the partial development views H1 to _n whose shooting time is around, respectively, and the axial direction and the circumferential direction at the time of matching The conversion distance and the conversion direction are respectively calculated.

The partial development view connecting unit 35 connects the partial development views H 1 to _n whose shooting times are changed based on the axial direction and circumferential conversion distances and conversion directions calculated by the feature point matching unit 34 to form a borehole. A hole wall development H _all over the entire length is generated.

Next, a procedure for photographing the inner wall of the boring hole using the photographing carriage 1 will be described in detail with reference to FIG.
First, one or more marks M serving as reference positions are installed on the inner wall of the borehole to be observed. The mark M can be installed anywhere as long as it can be photographed by the omnidirectional camera 11 of the photographing carriage 1, for example, a place that is easy to install about 1 m from the entrance may be selected.

  Next, with the tow rope 16 attached to the photographing carriage 1, it is inserted into the boring hole and travels to the innermost part. The towline 16 may also be used as a communication cable between the omnidirectional camera 11 and the front camera 12 of the photographing cart 1 and the hole wall development drawing generating device 2. When the boring hole is a vertical hole or has a downward inclination, the photographing cart 1 can be driven by its own weight. When the boring hole is a horizontal hole, the boring hole may be pushed by a stick, or the photographing cart 1 may have a self-propelling function.

  When the photographing carriage 1 is traveled to the deepest part of the borehole, it is preferable to display the image photographed by the front camera 12 on the development drawing output unit 6 of the hole wall development drawing generation device 2 in real time. Thereby, the situation in the hole can be confirmed, and it can be determined whether or not the photographing cart 1 has reached the innermost part of the boring hole.

  Next, the inner wall of the boring hole is photographed by the omnidirectional camera 11 while pulling the towline 16 and causing the photographing cart 1 to run forward. The speed at which the photographing cart 1 travels does not have to be constant.

Next, the generation operation of the hole wall development view by the hole wall development view generation device 2 will be described in detail with reference to FIG. 4 and FIG.
First, the image acquisition unit 31 acquires shooting data P 1 to _n for each predetermined time as shown in FIG. 4A from the omnidirectional camera 11. In FIG. 4A, photographing data P1 to _P4 acquired by the image acquisition unit 31 are shown.

As illustrated in FIG. 4B, the partial development view generation unit 32 generates and stores partial development views H 1 _{to n} from the photographing data P 1 to _n acquired every predetermined time acquired by the image acquisition unit 31. Store in part 4. FIG. 4B shows partial development views _H1-4 generated from the photographing data _P1-4 . Hereinafter, an operation until the partial development views H1 to ₄ are connected by the partial development view connecting portion 35 will be described.

Next, as shown in FIG. 4C, the feature point extraction unit 33 extracts a plurality of “feature points” from the partial development views H ₁ to ₄ , respectively, and the image coordinates (x , Y) are respectively generated as feature point monitor data D 1 to _n and stored in the storage unit 4. In FIG. 4C, white + marks indicate “feature points”.

Next, as shown by arrows A ₁₂ , A ₂₃ , and A ₃₄ in FIG. 5A, the feature point matching unit 34 uses a feature point matching technique, and a partial development view H _{1- The four} feature point monitor data D1 to _D4 are matched. Then, as shown by arrows B ₁₂ , B ₂₃ , and B ₃₄ in FIG. 5A, the feature point matching unit 34 changes the axial distance and the circumferential direction conversion distance and the conversion direction at the time of matching by changing the shooting time. Calculation is performed for each of the partial development views H1 to _H4 . In FIG. 5A, two matching pairs are illustrated, but in practice, a large number of matching pairs are obtained, and the feature point matching unit 34 sets a threshold value in which the number of feature point matching pairs is set in advance. In the above case, the partial development views H 1 to _{n in} which the photographing time is changed are determined as matching.

Partial development view where shooting time fluctuates. When the feature point monitor data D _m-1 and D _{m of} H _m-1 and H _m do not match, the traveling speed of the shooting cart 1 is too fast and the shooting time fluctuates. or if a region overlapping with the developed view H _m-1 and partial development view H _m is small, it will be different from the distance Ra and the distance Rb by vibration or the like, partial development view H _m-1 and the portion capturing time may be around A case in which a change occurs in the photographing condition with the development view H _m can be considered. Therefore, when the photographing by the omnidirectional camera 11 and the generation operation of the hole wall development view by the hole wall development drawing generation device 2 are performed in parallel, the feature point matching unit 34 changes the photographing time. Of the partial development views H _m−1 and H _m , the partial development view H _m that was captured later is deleted, and the warning output unit 5 outputs a warning by sound or display. Thereby, the worker can return the photographing cart 1 in the reverse direction and redo the photographing with the omnidirectional camera 11.

Further, after taking over the borehole entire length by omnidirectional camera 11, it may be performed to generate operations of the pore walls developed view H _all by pore walls development diagram generating apparatus 2. In this case, with respect to the traveling speed of the imaging cart 1, the time interval of the imaging data acquired by the image acquisition unit 31 is sufficiently shortened, and the partial development views H _m−1 and H _m overlapping the imaging time. Increase Then, when the feature point monitor data D _m-1 and D _m of the partial development views H _m-1 and H _m do not match, the feature point matching unit 34 deletes the partial development view H _m captured later. Then, the partially developed view H _{m + 1} of the image taken later is matched with the partially developed view H _m-1 of the image taken earlier. Thus, it is possible to generate a more accurate hole wall exploded view H _all to remove the bad data. Note that when the number of partial development views that do not match the partial development view H _m−1 has been set in advance continuously after the partial development view H _m , the feature point matching unit 34 uses the warning output unit 5. It is good to output a warning with sound and display.

Next, as shown in FIG. 5B, the partial development view connecting unit 35 changes the imaging time based on the axial direction and circumferential conversion distances and conversion directions calculated by the feature point matching unit 34. generating a porous wall developed view _{H 1 to 4} linked to partial development view _{H 1 to 4.} In this way, the partial developed views H 1 to _n whose shooting times are changed are connected to generate the hole wall developed view H _all over the entire borehole. Then, the inclusion is mark M as a reference position in the hole wall developed view H _all, it is possible to grasp the position over the borehole length.

When connecting the partial development views H1 to ₄ whose shooting times are before and after, priority is given to an image closer to a circumferential line (hereinafter referred to as a center line C) through which the optical axis of the omnidirectional camera 11 passes. . That is, in the hole wall development views H _{1 to 4} , the closer the strain is to the center line C, the smaller the strain. Therefore, by giving priority to the image closer to the center line C, the hole wall can be reproduced more accurately.

As described above, the present embodiment generates the hole wall unfolded view H _all from the photographing cart 1 equipped with the omnidirectional camera 11 for photographing the inner wall of the boring hole and the photographing data photographed by the photographing cart 1. The hole wall development diagram generating device 2 includes an image acquisition unit 31 that acquires imaging data every predetermined time, and from the imaging data acquired by the image acquisition unit 31, a borehole A partial unfolded view generating unit 32 for generating 360 degree panoramic images having a predetermined length in the circumferential direction as partially developed views H1 to _n , and a partially developed view generated by the partially developed view generating unit 32. matching feature point extraction unit 33 for generating feature point monitor data _{D 1 to n} obtained by extracting the feature points, the feature point monitor data _D1~n partial development view _{H 1 to n} the recording time may be around from H _{1 to n} And a feature point matching unit 34 for calculating a conversion distance and a conversion direction in the axial direction and the circumferential direction at the time of matching, respectively, and a conversion distance and a conversion direction in the axial direction and the circumferential direction calculated by the feature point matching unit 34 , and a partial development view connecting portion 35 the recording time to produce a pore walls development view H _all by connecting the partial development view H _{1 to n} to the front and rear.
With this configuration, the partial development views H 1 to _n generated from the imaging data can be connected without using a precise distance measurement result, and the hole wall can be easily observed using an inexpensive camera.

Further, in the present embodiment, after imaging by omnidirectional camera 11, when performing the operation of generating the pore walls developed view H _all by pore walls development diagram generating apparatus 2, the feature point matching unit 34, imaging time before and after If the feature point monitor data D 1 to _{n of} the partial development views H _m−1 and H _{m to} be matched do not match, the later developed partial development view H _m is deleted, and further the partial development view H _{m + 1} taken later Is matched with the partial development view H _{m−1 of} the one photographed before.
With this configuration, it is possible to generate a more accurate hole wall exploded view H _all to remove the bad data.

Further, in this embodiment, it comprises a warning output section 5 for outputting a warning, and capturing by the omnidirectional camera 11, in parallel with generation operation of the hole wall developed view H _all by pore walls development diagram generating apparatus 2 In the case where the feature point matching unit 34 does not match the feature point monitor data D _m−1 and D _{m of} the partial development views H _m−1 and H _m where the shooting time varies, the warning output unit 5 Will output a warning.
With this configuration, the worker can return the photographing cart 1 in the reverse direction and redo the photographing with the omnidirectional camera 11.

Further, in the present embodiment, the feature point matching unit 34 is photographed later when the feature point monitor data D _m−1 and D _{m of} the partial development views H _m−1 and H _m whose photographing time is varied do not match. The partial development view _Hm is deleted.
With this configuration, it is possible to generate a more accurate hole wall exploded view H _all to remove the bad data.

Furthermore, in this embodiment, the omnidirectional camera 11 includes two imaging optical systems 15a and 15b that are combined in opposite directions so that their optical axes coincide with each other. The optical axes of the systems 15a and 15b are orthogonal to the central axis of the borehole, and the distance Ra and Rb on the optical axis between the two imaging optical systems 15a and 15b and the inner wall of the borehole are the same. A centralizer 14 that supports the spherical camera 11 on the central axis of the borehole is provided.
With this configuration, it is possible to generate partial development views H 1 to _n with small distortion under the same conditions.

Further, in the present embodiment, the partial development view generation unit 32 is configured such that the circumferential line of the borehole passing through the optical axes of the imaging optical systems 15a and 15b of the omnidirectional camera 11 is the center line C in the axial direction of the borehole. Partially developed views H 1 to _n are generated.
With this configuration, it is possible to generate partial development views H 1 to _n with small distortion.

  The present invention has been described above based on the embodiments. This embodiment is an exemplification, and it is understood by those skilled in the art that various modifications can be made to combinations of the respective components and the like, and such modifications are also within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Shooting cart 11 Spherical camera 12 Front camera 13 Illumination 14 Centralizers 15a and 15b Imaging optical system 16 Towline 2 Hole wall development drawing device 3 Control unit 4 Storage unit 5 Warning output unit 6 Development drawing output unit 31 Image acquisition unit 32 Partial development diagram generation unit 33 Feature point extraction unit 34 Feature point matching unit 35 Partial development diagram connection unit

Claims (7)

A trolley equipped with a camera that shoots the inner wall of the borehole;
A hole wall development view generating device for generating a hole wall development view from the photographing data photographed by the photographing carriage,
The hole wall development drawing generating device is:
An image acquisition unit for acquiring the photographing data for each predetermined time;
A partial development view generating section for generating a 360 degree panoramic image as a partial development view from the photographing data acquired by the image acquisition section, the axial direction of the boring hole being a predetermined length and copying the entire circumferential direction;
A feature point extraction unit that generates feature point monitor data obtained by extracting feature points from the partial development view generated by the partial development view generation unit;
A feature point matching unit that matches the feature point monitor data of the partial development view whose shooting time is before and after, and calculates a conversion distance and a conversion direction in the axial direction and the circumferential direction at the time of matching, and
A partial development view linking unit that generates the hole wall development view by connecting the partial development views whose shooting time is changed based on the axial direction and circumferential conversion distances and conversion directions calculated by the feature point matching unit. And a hole wall observation system. When performing the operation of generating the hole wall development view by the hole wall development view generation device after photographing by the camera,
If the feature point monitor data of the partial development view whose shooting time is before and after does not match, the feature point matching unit deletes the partial development view that was taken later, and the portion that was taken later The hole wall observation system according to claim 1, wherein a development view is matched with the partial development view of the image taken earlier. A warning output unit for outputting a warning;
In the case where the photographing by the camera and the generation operation of the hole wall development view by the hole wall development drawing generation device are performed in parallel,
2. The hole wall observation system according to claim 1, wherein the feature point matching unit outputs a warning by the warning output unit when the feature point monitor data of the partial development view whose photographing time is around does not match. .   The feature point matching unit, if the feature point monitor data of the partial development view whose photographing time is before and after does not match, deletes the partial development view of the later photographed one. Hole wall observation system. The camera is an omnidirectional camera provided with two imaging optical systems that are combined in opposite directions so that their optical axes match.
In the photographing cart, the optical axis of the imaging optical system is orthogonal to the central axis of the boring hole, and the distances on the optical axis between the two imaging optical systems and the inner wall of the boring hole are the same. The hole wall observation system according to claim 1, further comprising a centralizer that supports the omnidirectional camera on a central axis of the borehole.   The partial development view generation unit generates the partial development view in which a circumferential line of the borehole passing through the optical axis of the imaging optical system of the omnidirectional camera is a central line in the axial direction of the borehole. The hole wall observation system according to claim 5, wherein: A trolley equipped with a camera that shoots the inner wall of the borehole,
As the camera, an omnidirectional camera equipped with two imaging optical systems that are combined in opposite directions so that their optical axes match,
The omnidirectional camera so that the optical axis of the imaging optical system is orthogonal to the central axis of the borehole and the distance between the two imaging optical systems and the inner wall of the borehole is the same on the optical axis A photographing carriage comprising a centralizer that supports a central axis of the boring hole.

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