Method, system, equipment and medium for determining the starting position of the first mining layer in the upper part of the caving area

Abstract

The present invention relates to a method, system, equipment and medium for determining the starting position of the first mining layer at the top of a caving area. The method comprises: obtaining the position of each exploration line on the caving area, taking the position of each exploration line as the current position, and obtaining the lower plate rock movement angle at the current position; determining the movement belt of the caving area at the current position according to the lower plate rock movement angle; determining the lower plate rock movement line boundary of the caving area at the current position according to the movement belt; collecting the thickness of each horizontal safety pillar at a preset distance from the lower plate rock movement line boundary according to the lower plate rock movement line boundary; determining the reserved thickness of the horizontal safety pillar at the current position according to the thickness of each horizontal safety pillar; and determining the starting position of the first mining layer cutting route at the current position according to the reserved thickness. The method solves the problem that the thickness of the horizontal safety pillars in the entire caving area cannot be accurately reserved, resulting in the inability to determine the starting elevation position of the first mining layer cutting route.

Description

Background Art

[0002] During the mining process of underground mines, some areas of the mining field inevitably experience some collapse phenomena due to the poor stability of the ore rock, and due to the lack of filling, a caving area is formed. When the downward approach is carried out for recovery in the upper part of the caving area, in order to ensure the safety of the first mining layer cutting approach, a certain thickness of horizontal safety pillars must be left between the first mining layer cutting approach and the caving area. If the thickness of the horizontal safety pillars in a certain section of the caving area is large, it will cause a large loss of resources; if the thickness of the horizontal safety pillars in a certain section of the caving area is small, safe mining cannot be guaranteed; in engineering practice, there is currently no unified scientific method for setting the thickness of the horizontal safety pillars, and empirical methods and numerical simulation methods are often used. Although the empirical method is simple, it is generally more conservative and results in a large loss of ore; the numerical simulation method idealizes and simplifies the complex geological conditions, and the error of its analysis results is large. Therefore, once the horizontal safety pillars of the entire caving area cannot be accurately left, the starting elevation position of the first mining layer cutting approach cannot be determined. Summary of the invention

[0003] In order to solve the problem that the thickness of the horizontal safety pillars in the entire caving area cannot be accurately set, resulting in the inability to determine the starting elevation position of the first mining layer cutting route, the present invention provides a method, system, equipment and medium for determining the starting position of the upper first mining layer in the caving area.

[0004] In a first aspect, in order to solve the above technical problems, the present invention provides a method for determining the starting position of the first mining layer in the upper part of the caving area, comprising the following steps:

[0005] S1, obtaining the position of each exploration line on the caving area, taking the position of each exploration line as the current position, and obtaining the footwall rock movement angle at the current position, wherein the footwall rock movement angle represents the angle between the line connecting the footwall rock movement boundary and the horizontal plane;

[0006] S2, determining a moving zone of the caving area at the current position according to the rock movement angle of the lower plate, wherein the moving zone represents a range where the ore rock moves;

[0007] S3, determining the rock line boundary of the lower plate of the caving area at the current position according to the moving zone, wherein the rock line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving zone of the caving area;

[0008] S4, according to the lower wall rock shift line boundary, collecting the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary;

[0009] S5, determining the remaining thickness of the horizontal safety pillar at the current position according to the thickness of each horizontal safety pillar;

[0010] S6, determining the starting position of the first mining layer cutting route at the current position according to the reserved thickness.

[0011] The beneficial effect of the method for determining the starting position of the first mining layer in the upper part of the caving area provided by the present invention is: taking the position of each exploration line as the current position, determining the movement angle of the lower plate rock at the current position, determining the movement belt according to the movement angle of the lower plate rock, determining the boundary of the lower plate rock movement line according to the movement belt, collecting the thickness of each horizontal safety pillar at a preset distance from the boundary of the lower plate rock movement line, and determining the retained thickness of the horizontal safety pillar according to the thickness of each horizontal safety pillar. When the retained thickness of the horizontal safety pillar at the position of each exploration line is obtained, the retained thickness of the horizontal safety pillar in the entire caving area can be obtained. Since the retained thickness of the horizontal safety pillar at the position of each exploration line in the caving area is taken into account, the retained accuracy of the thickness of the horizontal safety pillar in the entire caving area is ensured, and the problem that the thickness of the horizontal safety pillar in the entire caving area cannot be accurately retained, resulting in the inability to determine the starting elevation position of the first mining layer cutting route, is solved.

[0012] On the basis of the above technical solution, the method for determining the starting position of the first mining layer in the upper part of the caving area of ​​the present invention can also be improved as follows.

[0013] Furthermore, S4 specifically includes:

[0014] According to the lower rock shift line boundary, the starting position is 0m from the lower rock shift line boundary, and the thickness of the horizontal security pillars at every 2m position starting from the starting position is collected.

[0015] The beneficial effect of adopting the above further solution is: collecting the thickness of horizontal security pillars at multiple preset distances, thereby improving the accuracy and rationality of the data.

[0016] Furthermore, according to the lower rock displacement line boundary, the lower rock displacement line boundary 0m is taken as the starting position, and the thickness of the horizontal security pillars at every 2m position starting from the starting position is collected, including:

[0017] According to the boundary of the lower wall rock shift line, the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the target lower wall rock shift line boundary is collected respectively.

[0018] The beneficial effect of adopting the above further scheme is: in order to improve efficiency, the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the boundary of the target lower wall rock migration line can be collected respectively.

[0019] Further, according to the thickness of each horizontal safety pillar, the thickness of the horizontal safety pillar at the current position is determined, including:

[0020] The thickness of the horizontal safety pillar with the largest thickness among all horizontal safety pillars is selected as the preset thickness.

[0021] The beneficial effect of adopting the above further solution is: the thickness of the horizontal safety pillar with the largest thickness among all horizontal safety pillars is selected as the preset thickness, thereby ensuring safety.

[0022] In a second aspect, the present invention provides a system for determining the starting position of the first mining layer in the upper part of the caving area, comprising:

[0023] The first determination module is used to obtain the position of each exploration line on the caving area, take the position of each exploration line as the current position, and obtain the rock movement angle of the lower plate at the current position, wherein the rock movement angle of the lower plate represents the angle between the line connecting the rock movement boundary of the lower plate and the horizontal plane;

[0024] The second determination module is used to determine the movement zone of the caving area at the current position according to the movement angle of the lower plate rock, and the movement zone represents the range of the movement of the ore rock;

[0025] A third determination module is used to determine the rock line boundary of the lower plate of the caving area at the current position according to the moving belt, wherein the rock line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving belt of the caving area;

[0026] A fourth determination module is used to collect the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary according to the lower wall rock shift line boundary;

[0027] A fifth determination module, used to determine the thickness of the horizontal safety pillars at the current position according to the thickness of each of the horizontal safety pillars;

[0028] The sixth determination module is used to determine the starting position of the first mining layer cutting route at the current position according to the reserved thickness.

[0029] The beneficial effects of the system for determining the starting position of the first mining layer in the upper part of the caving area provided by the present invention are: taking the position of each exploration line as the current position, determining the movement angle of the lower plate rock at the current position, determining the moving belt according to the movement angle of the lower plate rock, determining the boundary of the lower plate rock movement line according to the moving belt, collecting the thickness of each horizontal safety pillar at a preset distance from the boundary of the lower plate rock movement line, and determining the retained thickness of the horizontal safety pillar according to the thickness of each horizontal safety pillar. When the retained thickness of the horizontal safety pillar at the position of each exploration line is obtained, the retained thickness of the horizontal safety pillar in the entire caving area can be obtained. Since the retained thickness of the horizontal safety pillar at the position of each exploration line in the caving area is taken into account, the retained accuracy of the thickness of the horizontal safety pillar in the entire caving area is ensured, and the problem that the thickness of the horizontal safety pillar in the entire caving area cannot be accurately retained, resulting in the inability to determine the starting elevation position of the first mining layer cutting route, is solved.

[0030] Further, the fourth determination module includes:

[0031] The seventh determination module is used to collect the thickness of the horizontal security pillars at every 2m position starting from the starting position, based on the lower plate rock shift line boundary, with 0m of the lower plate rock shift line boundary as the starting position.

[0032] The beneficial effect of adopting the above further solution is: collecting the thickness of horizontal security pillars at multiple preset distances, thereby improving the accuracy and rationality of the data.

[0033] Further, the seventh determination module includes:

[0034] The eighth determination module is used to collect the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the target lower wall rock shift line boundary according to the lower wall rock shift line boundary.

[0035] The beneficial effect of adopting the above further scheme is: in order to improve efficiency, the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the boundary of the target lower wall rock migration line can be collected respectively.

[0036] Further, the fifth determination module includes:

[0037] The ninth determination module is used to select the thickness of the horizontal safety pillar with the largest thickness among the horizontal safety pillars as the preset thickness.

[0038] The beneficial effect of adopting the above further solution is: the thickness of the horizontal safety pillar with the largest thickness among all horizontal safety pillars is selected as the preset thickness, thereby ensuring safety.

[0039] In a third aspect, the present invention further provides an electronic device comprising a memory, a processor and a program stored in the memory and running on the processor, wherein when the processor executes the program, the steps of the method for determining the starting position of the first mining layer in the upper part of the caving area as described above are implemented.

[0040] In a fourth aspect, the present invention further provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes the steps of the method for determining the starting position of the first mining layer in the upper part of the caving area as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0042] Figure 1 It is a flow chart of a method for determining the starting position of the first mining layer in the upper part of a caving area according to an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the structure of the falling area of ​​an embodiment of the present invention;

[0044] Figure 3 It is a structural schematic diagram of a system for determining the starting position of the first mining layer in the upper part of a caving area according to an embodiment of the present invention;

[0045] Figure 4 This is a cross-sectional view of the ore body along the strike direction according to an embodiment of the present invention.

[0046] Description of the accompanying drawings: ore body 1, caving area 2, exploration line 3, horizontal safety pillar 4, first mining layer cutting route 5. DETAILED DESCRIPTION

[0047] The following examples are provided to further explain and supplement the present invention and do not constitute any limitation to the present invention.

[0048] The following describes the method for determining the starting position of the first mining layer in the upper part of the caving area, the method for determining the starting position of the first mining layer in the upper part of the caving area, the system, the device and the medium of the embodiment of the present invention in conjunction with the accompanying drawings.

[0049] like Figure 1 As shown, the method for determining the starting position of the first mining layer in the upper part of the caving area according to the embodiment of the present invention comprises the following steps:

[0050] S1, obtain the position of each exploration line on the caving area, take the position of each exploration line as the current position, and obtain the lower plate rock movement angle at the current position. The lower plate rock movement angle represents the angle between the line connecting the lower plate rock movement boundary and the horizontal plane.

[0051] like Figure 2As shown, the left side of the caving area is called the upper wall rock, and the right side of the caving area is called the lower wall rock.

[0052] In this embodiment, in order to more accurately determine the thickness of the horizontal safety pillars on the entire caving area, multiple exploration lines are marked on the caving area, and the position of each exploration line is taken as the current position. By repeating S1-S6, the starting position of the first mining layer cutting route at the current position can be obtained. After obtaining the starting position of the first mining layer cutting route at each exploration line, the starting position of the first mining layer cutting route of the entire caving area can be obtained.

[0053] S2, according to the rock movement angle of the lower plate, determine the movement zone of the caving area at the current position. The movement zone represents the range of the movement of the ore rock.

[0054] S3, determining the rock shift line boundary of the lower plate of the caving area at the current position according to the moving belt, wherein the rock shift line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving belt of the caving area.

[0055] like Figure 2 As shown in the figure, the line connecting the outermost boundary position of the footwall of the caving area and the boundary of the moving zone of the caving area is selected as the boundary of the footwall rock movement line, among which the outermost boundary position of the footwall of the caving area is as shown in the figure. Figure 2 Point a in .

[0056] S4, according to the lower wall rock shift line boundary, collecting the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary.

[0057] Optionally, the starting distance is 0 m from the boundary of the lower plate rock migration line, and the thickness of the horizontal security pillar is sampled every 2 m from the starting distance.

[0058] In this embodiment, the preset distances are 0m, 2m, 4m and 6m, that is, the starting distance is 0m from the boundary of the lower rock shift line, and the thickness of the horizontal safety pillars at 0m, 2m, 4m and 6m from the boundary of the lower rock shift line are collected from the starting distance.

[0059] S5, determining the remaining thickness of the horizontal safety pillar at the current position according to the thickness of each horizontal safety pillar.

[0060] Optionally, when the thickness of the horizontal safety pillars at 0m, 2m, 4m and 6m from the boundary of the lower rock shift line are collected, the thickness of the horizontal safety pillar with the largest thickness among the horizontal safety pillars obtained at an appropriate distance from the boundary of the lower rock shift line can be selected as the preset thickness based on the experience of the rock stability of the engineering site.

[0061] S6, determining the starting position of the first mining layer cutting route at the current position according to the reserved thickness.

[0062] like Figure 3 As shown, the system for determining the starting position of the first mining layer in the upper part of the caving area according to the embodiment of the present invention comprises:

[0063] The first determination module 202 is used to obtain the position of each exploration line on the caving area, take the position of each exploration line as the current position, and obtain the footwall rock movement angle at the current position, wherein the footwall rock movement angle represents the angle between the line connecting the footwall rock movement boundary and the horizontal plane;

[0064] The second determination module 203 is used to determine the movement zone of the caving area at the current position according to the movement angle of the lower plate rock, and the movement zone represents the range of the movement of the ore rock;

[0065] The third determination module 204 is used to determine the rock line boundary of the lower plate of the caving area at the current position according to the moving zone, wherein the rock line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving zone of the caving area;

[0066] The fourth determination module 205 is used to collect the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary according to the lower wall rock shift line boundary;

[0067] The fifth determination module 206 is used to determine the thickness of the horizontal safety pillar at the current position according to the thickness of each horizontal safety pillar;

[0068] The sixth determination module 207 is used to determine the starting position of the first mining layer cutting route at the current position according to the reserved thickness.

[0069] Optionally, the fourth determining module 205 includes:

[0070] The seventh determination module is used to collect the thickness of the horizontal security pillars at every 2m position starting from the starting position, based on the lower plate rock shift line boundary, with 0m of the lower plate rock shift line boundary as the starting position.

[0071] Optionally, the seventh determination module includes:

[0072] The eighth determination module is used to collect the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the target lower wall rock shift line boundary according to the lower wall rock shift line boundary.

[0073] Optionally, the fifth determining module 206 includes:

[0074] The ninth determination module is used to select the thickness of the largest horizontal security pillar among the horizontal security pillars as the preset thickness.

[0075] A specific application of this embodiment:

[0076] like Figure 4 As shown, the horizontal axis represents the exploration line coordinates, and the vertical axis represents the elevation of the ore body. The entire caving area 2 is marked by multiple exploration lines 3, including multiple exploration lines 3 from 2310 to 2610 from right to left. Figure 4 The trend of the middle caving area 2 can divide the entire caving area 2 into two parts, one of which is the caving area 2a located between the 2543-2610 exploration lines 3, and the roof elevation of the caving area 2a is located at 540.5ml; the other is the caving area 2b located between the 2543-2310 exploration lines 3, and the roof elevation of the caving area 2b is located at 555.6ml. In this embodiment, the 2340 exploration line 3, the 2400 exploration line 3, the 2520 exploration line 3 and the 2580 exploration line 3 are respectively used as the current position, so that the movement angle of the lower wall surrounding rock at the current position is 70°, and then the current position is taken as the main standard, and the thickness of the horizontal security pillars of 0m, 2m, 4m and 6m from the boundary of the lower wall rock movement line at the current position are collected, and the corresponding range values ​​are generated, as shown in the following Table 1:

[0077] Table 1

[0078]

[0079]

[0080] In Table 1, for example, sequence number 1 represents the range value of the thickness of the horizontal safety pillars of exploration line 3 of 2340, exploration line 3 of 2400, exploration line 3 of 2520 and exploration line 3 of 2580 at a distance of 0 m from the boundary of the lower plate rock migration line. According to Table 1, the thickness of the horizontal safety pillar with the largest thickness in each sequence number can be selected as the preset thickness in combination with the experience of the rock stability of the engineering site. In this embodiment, according to the experience of the on-site rock stability engineering, the maximum value in the thickness range of the horizontal safety pillar at 4 m from the boundary of the lower plate rock migration line is selected as the preset thickness, as shown in Table 2 below:

[0081] Table 2

[0082]

[0083] In the present embodiment, since anchor rods, anchor cables and other supports are required during the mining process of the ore body in the upper part of the caving area 2, the closer to the boundary of the lower plate rock shift line, the less ideal the support effect of anchor rods, anchor cables and other supports is, and the farther the distance is, the better the support effect will be. However, at the same time, the thicker the horizontal safety pillar 4 that needs to be left, the more ore will be lost. Therefore, according to the experience of the ore and rock stability at the engineering site, the present embodiment can select the thickness of the horizontal safety pillar 8 at 4m away from the boundary of the lower plate rock shift line, and finally, through the thickness of the horizontal safety pillar 8 at 4m away from the boundary of the lower plate rock shift line at each current position, take the maximum thickness of the horizontal safety pillar as the reserved thickness, which is specifically 10.5m. Figure 4 Among them, the starting elevation of the first mining layer cutting route between the 2543-2310 exploration line 3 is at 545.1ml, and the starting elevation of the first mining layer cutting route between the 2543-2610 exploration line 3 is at 530ml.

[0084] An electronic device according to an embodiment of the present invention comprises a memory, a processor and a program stored in the memory and running on the processor. When the processor executes the program, part or all of the steps of the method for determining the starting position of the first mining layer in the upper part of the caving area are implemented.

[0085] Among them, the electronic device can be a computer, a mobile phone, etc. Correspondingly, its program is a computer software or a mobile phone APP, etc., and the above-mentioned parameters and steps in an electronic device of the present invention can refer to the parameters and steps in the embodiment of the method for determining the starting position of the first mining layer in the upper part of the caving area in the above text, which will not be repeated here.

[0086] Those skilled in the art know that the present invention can be implemented as a system, method or computer program product. Therefore, the present disclosure can be specifically implemented in the following forms, namely: it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), or it can be a combination of hardware and software, generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code. Computer-readable storage media can be, for example, but not limited to - electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above.

[0087] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0088] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. Method for determining the starting position of the first mining layer in the upper part of the caving area, It is characterized in that The following steps are involved: S1, obtaining the position of each exploration line on the caving area, taking the position of each exploration line as the current position, and obtaining the footwall rock movement angle at the current position, wherein the footwall rock movement angle represents the angle between the line connecting the footwall rock movement boundary and the horizontal plane; S2, determining a moving zone of the caving area at the current position according to the rock movement angle of the lower plate, wherein the moving zone represents a range where the ore rock moves; S3, determining the rock line boundary of the lower plate of the caving area at the current position according to the moving zone, wherein the rock line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving zone of the caving area; S4, according to the lower wall rock shift line boundary, collecting the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary; S5, determining the remaining thickness of the horizontal safety pillar at the current position according to the thickness of each horizontal safety pillar; S6, determining the starting position of the first mining layer cutting route at the current position according to the reserved thickness; The S4 specifically includes: According to the lower rock displacement line boundary, the lower rock displacement line boundary 0m is taken as the starting position, and the thickness of the horizontal security pillars at every 2m position starting from the starting position is collected; According to the lower rock shift line boundary, the lower rock shift line boundary 0m is taken as the starting position, and the thickness of the horizontal security pillars at every 2m position starting from the starting position is collected, including: According to the lower wall rock shift line boundary, the thickness of each horizontal security pillar at the position of 0m, 2m, 4m and 6m away from the lower wall rock shift line boundary is collected respectively; Determining the thickness of the horizontal safety pillars at the current position according to the thickness of each of the horizontal safety pillars includes: The thickness of the horizontal safety pillar with the largest thickness among the horizontal safety pillars is selected as the preset thickness.

2. System for determining the starting position of the first mining layer in the upper part of the caving area, It is characterized in that include: The first determination module is used to obtain the position of each exploration line on the caving area, take the position of each exploration line as the current position, and obtain the rock movement angle of the lower plate at the current position, wherein the rock movement angle of the lower plate represents the angle between the line connecting the rock movement boundary of the lower plate and the horizontal plane; The second determination module is used to determine the movement zone of the caving area at the current position according to the movement angle of the lower plate rock, and the movement zone represents the range of the movement of the ore rock; A third determination module is used to determine the rock line boundary of the lower plate of the caving area at the current position according to the moving belt, wherein the rock line boundary of the lower plate represents the line connecting the outer end boundary position of the lower plate of the caving area and the boundary of the moving belt of the caving area; A fourth determination module is used to collect the thickness of each horizontal security pillar at a preset distance from the lower wall rock shift line boundary according to the lower wall rock shift line boundary; A fifth determination module, used to determine the thickness of the horizontal safety pillars at the current position according to the thickness of each of the horizontal safety pillars; A sixth determination module is used to determine the starting position of the first mining layer cutting route at the current position according to the reserved thickness of the horizontal safety pillar; The fourth determination module comprises: A seventh determination module is used to collect the thickness of the horizontal security pillars at every 2m position starting from the starting position, based on the lower plate rock shift line boundary, with 0m of the lower plate rock shift line boundary as the starting position; The seventh determination module comprises: An eighth determination module is used to collect the thickness of each horizontal security pillar at a position of 0m, 2m, 4m and 6m away from the lower wall rock shift line boundary according to the lower wall rock shift line boundary; The fifth determining module comprises: The ninth determination module is used to select the thickness of the horizontal safety pillar with the largest thickness among the horizontal safety pillars as the preset thickness.

3. An electronic device comprising a memory, a processor, and a program stored in the memory and running on the processor, It is characterized in that When the processor executes the program, the steps of the method for determining the starting position of the first mining layer in the upper part of the caving area as described in claim 1 are implemented.

4. A computer-readable storage medium, It is characterized in that The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes the steps of the method for determining the starting position of the first mining layer in the upper part of a caving area as described in claim 1.

Images