阅读说明：本技术 一种多屏幕电表抄表专家系统及方法 (Multi-screen ammeter meter reading expert system and method ) 是由 刘飞 傅帅 赵秀伟 于 2020-05-12 设计创作，主要内容包括：本发明的实施例提供一种多屏幕电表抄表专家系统及方法,多屏幕电表抄表系统包括：抄表终端,用于按照预配置的拍照次数和拍照间隔拍摄一组照片,所述一组照片包含多屏表的每个屏幕,将所述一组照片上传至抄表平台；抄表平台,用于接收所述一组照片,获取所述一组照片的特征值,并将所述特征值发送给所述抄表终端。本发明的方案可以实现对不同表型、不同特征的适配,同时基于云端结合的边缘计算能力,可以降低传输功耗,从而降低了设备的成本。(The embodiment of the invention provides a multi-screen electric meter reading expert system and a method thereof, wherein the multi-screen electric meter reading system comprises: the meter reading terminal is used for shooting a group of photos according to the pre-configured shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen meter, and the group of photos are uploaded to the meter reading platform; and the meter reading platform is used for receiving the group of photos, acquiring the characteristic values of the group of photos and sending the characteristic values to the meter reading terminal. The scheme of the invention can realize the adaptation to different phenotypes and different characteristics, and simultaneously can reduce the transmission power consumption based on the edge computing capability of cloud combination, thereby reducing the cost of equipment.)

1. The utility model provides a many screen ammeter expert system of checking meter which characterized in that includes:

the meter reading terminal is used for shooting a group of photos according to the pre-configured shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen meter, and the group of photos are uploaded to the meter reading platform;

and the meter reading platform is used for receiving the group of photos, acquiring the characteristic values of the group of photos and sending the characteristic values to the meter reading terminal.

2. The expert system for meter reading from electric meters on multiple screens of claim 1, wherein the number of shots and the shot interval cover a transition period of the multiple screens.

3. The multi-screen electric meter reading expert system of claim 1, wherein the meter reading platform performs image recognition on the group of photos after receiving the group of photos, selects at least one target photo from the group of photos, obtains a characteristic value of the group of photos, and sends the characteristic value to the meter reading terminal.

4. The multi-screen electric meter reading expert system of claim 3, wherein the image recognition of the group of photographs to obtain the characteristic values of the group of photographs comprises:

using an image processing algorithm to distinguish different features of the same or multiple feature areas of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

5. The multi-screen electric meter reading expert system of claim 1, wherein the meter reading terminal is further configured to take a plurality of sets of photos according to the characteristic values and transmit the photos to the meter reading platform after receiving the characteristic values issued by the meter reading platform, or to select at least one target photo among the plurality of sets of photos according to the characteristic values and transmit the target photo to the meter reading platform.

6. A multi-screen ammeter reading method is applied to a meter reading terminal, and the method comprises the following steps:

receiving the photographing times and the photographing interval configured by the meter reading platform;

shooting a group of photos according to the shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen table;

and uploading the group of photos to a meter reading platform.

7. A multi-screen electric meter reading method according to claim 6, wherein the number of shots-the shot interval covers one hop period of the multi-screen meter.

8. The method of claim 6, further comprising:

receiving a characteristic value issued by the meter reading platform;

shooting a plurality of groups of photos according to the characteristic values and uploading the photos to the meter reading platform, or selecting at least one target photo from the plurality of groups of photos according to the characteristic values and then uploading the target photo to the meter reading platform.

9. A meter reading terminal, comprising:

the receiving module is used for receiving the photographing times and the photographing intervals configured by the meter reading platform;

the shooting module is used for shooting a group of photos according to the shooting times and the shooting intervals, and the group of photos comprise each screen of the multi-screen table;

and the sending module is used for uploading the group of photos to a meter reading platform.

10. A multi-screen ammeter reading method is applied to a meter reading platform, and comprises the following steps:

sending the photographing times and the photographing interval configured for the meter reading terminal to the meter reading terminal;

receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

acquiring characteristic values of the group of photos;

and sending the characteristic value to the meter reading terminal.

11. A multi-screen meter reading method according to claim 10, wherein obtaining the eigenvalues of the set of photographs comprises:

using an image processing algorithm to distinguish different features of the same or a plurality of feature positions of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

12. A meter reading platform, comprising:

the configuration module is used for configuring the photographing times and the photographing intervals for the meter reading terminal;

the receiving module is used for receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

the acquisition module is used for acquiring the characteristic values of the group of photos;

and the sending module is used for sending the characteristic value to the meter reading terminal.

13. A computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the method of any one of claims 6 to 8 or the method of any one of claims 10 to 11.

Technical Field

The invention relates to the technical field of meter reading systems, in particular to a multi-screen ammeter meter reading expert system and a multi-screen ammeter meter reading expert method.

Background

With the increase of manpower cost of electric power and hydraulic meter reading and the gradual development of the technology of the internet of things, remote meter reading gradually forms an independent technical field. Through the transformation of the water meter and the ammeter or through externally connecting terminal equipment on the water meter and the ammeter, the requirements of remote meter reading and identification can be realized. The meter is modified to have the remote communication capability, and the reading is remotely transmitted to the background. The method comprises the following steps of externally connecting terminal equipment, wherein one scheme is that a terminal shoots a meter photo, the photo is wirelessly transmitted to a platform, and intelligent identification is carried out on the platform; another solution is to use the infrared characteristics of the meters themselves, in particular some meters, to read the meter reading by infrared and transmit this reading wirelessly to the platform.

The multi-screen ammeter is characterized in that the ammeter is displayed in multiple screens, each screen stays for a period of time, switching is carried out according to a fixed sequence, and the display contents of the phenotypes are various and different phenotypes are different. The main requirement is that a certain screen in the screens is a target screen, and a picture of the screen needs to be taken and uploaded to a background for recognition. The current shot picture is uploaded to a remote meter reading terminal for recognition by a platform, and the shot picture of a target screen cannot be guaranteed. According to the scheme for reading the reading of the electric meter by infrared, on one hand, no picture is uploaded to a platform, and the credibility of the reading is ensured; on the other hand, not all multi-screen electric meters have the infrared reading function, so that the scheme cannot meet the requirements of all multi-screen electric meter reading.

In addition to meeting the above requirements, it is difficult to adapt to different phenotypes on the market, and it is difficult to have a general solution to meet the requirements of all phenotypes on the market.

Disclosure of Invention

The invention aims to provide a multi-screen ammeter reading expert system and method. The adaptation to different phenotypes, different characteristics can be realized, simultaneously based on the marginal computing power that the high in the clouds combines, transmission power consumption can be reduced to the cost of equipment has been reduced.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a multi-screen electric meter reading expert system, comprising:

the meter reading terminal is used for shooting a group of photos according to the pre-configured shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen meter, and the group of photos are uploaded to the meter reading platform;

and the meter reading platform is used for receiving the group of photos, acquiring the characteristic values of the group of photos and sending the characteristic values to the meter reading terminal.

Optionally, the number of shots and the shooting interval cover one jump cycle of the multi-screen table.

Optionally, after receiving the group of photos, the meter reading platform performs image recognition on the group of photos, selects at least one target photo from the group of photos, obtains a characteristic value of the group of photos, and sends the characteristic value to the meter reading terminal.

Optionally, performing image recognition on the group of photos to obtain feature values of the group of photos, including:

using an image processing algorithm to distinguish different features of the same or multiple feature areas of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

Optionally, the meter reading terminal is further configured to take multiple groups of photos according to the characteristic values and transmit the multiple groups of photos to the meter reading platform after receiving the characteristic values issued by the meter reading platform, or select at least one target photo from the multiple groups of photos according to the characteristic values and transmit the target photo to the meter reading platform.

The embodiment of the invention also provides a multi-screen ammeter reading method, which is applied to a meter reading terminal and comprises the following steps:

receiving the photographing times and the photographing interval configured by the meter reading platform;

shooting a group of photos according to the shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen table;

and uploading the group of photos to a meter reading platform.

Optionally, the number of shots and the shooting interval cover one jump cycle of the multi-screen table.

Optionally, the multi-screen electric meter reading method further includes:

receiving a characteristic value issued by the meter reading platform;

shooting a plurality of groups of photos according to the characteristic values and uploading the photos to the meter reading platform, or selecting at least one target photo from the plurality of groups of photos according to the characteristic values and then uploading the target photo to the meter reading platform.

An embodiment of the present invention further provides a meter reading terminal, including:

the receiving module is used for receiving the photographing times and the photographing intervals configured by the meter reading platform;

the shooting module is used for shooting a group of photos according to the shooting times and the shooting intervals, and the group of photos comprise each screen of the multi-screen table;

and the sending module is used for uploading the group of photos to a meter reading platform.

The embodiment of the invention also provides a multi-screen ammeter reading method, which is applied to a meter reading platform and comprises the following steps:

sending the photographing times and the photographing interval configured for the meter reading terminal to the meter reading terminal;

receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

acquiring characteristic values of the group of photos;

and sending the characteristic value to the meter reading terminal.

Optionally, obtaining the feature values of the group of photos includes:

using an image processing algorithm to distinguish different features of the same or a plurality of feature positions of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

An embodiment of the present invention further provides a meter reading platform, including:

the configuration module is used for configuring the photographing times and the photographing intervals for the meter reading terminal;

the receiving module is used for receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

the acquisition module is used for acquiring the characteristic values of the group of photos;

and the sending module is used for sending the characteristic value to the meter reading terminal.

Embodiments of the present invention also provide a computer-readable storage medium including instructions that, when executed on a computer, cause the computer to perform the method as described above.

The scheme of the invention at least comprises the following beneficial effects:

according to the scheme, a group of photos are shot through a meter reading terminal according to the pre-configured shooting times and the pre-configured shooting intervals, the group of photos comprise each screen of a multi-screen meter, and the group of photos are uploaded to a meter reading platform; and the meter reading platform receives the group of photos, acquires the characteristic values of the group of photos, and sends the characteristic values to the meter reading terminal. The adaptation to different phenotypes, different characteristics can be realized, simultaneously based on the marginal computing power that the high in the clouds combines, transmission power consumption can be reduced to the cost of equipment has been reduced.

Drawings

FIG. 1 is a schematic diagram of an expert system architecture for multi-screen electric meter reading according to an embodiment of the present invention;

FIG. 2 is a block diagram portion of a set of photographs featuring regions in accordance with an embodiment of the present invention;

FIG. 3 is a diagram illustrating the number of black pixels of a photo according to an embodiment of the present invention;

FIG. 4 is a schematic view of a selection interface for meter reading platform features in an embodiment of the invention;

FIG. 5 is a schematic view of another selection interface for meter reading platform features in an embodiment of the invention;

FIG. 6 is a schematic flow chart of a multi-screen electric meter reading method at a meter reading terminal side according to an embodiment of the present invention;

fig. 7 is another schematic flow chart of a multi-screen electric meter reading method on the meter reading platform side according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

As shown in fig. 1, an embodiment of the present invention provides a multi-screen electric meter reading expert system, including:

the meter reading terminal is used for shooting a group of photos according to the pre-configured shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen meter, and the group of photos are uploaded to the meter reading platform;

and the meter reading platform is used for receiving the group of photos, acquiring the characteristic values of the group of photos and sending the characteristic values to the meter reading terminal.

Here, the number of shots is one jump cycle of the multi-screen table covered by the shot interval. I.e., the multiscreen starts from one screen and switches to that screen again.

In an optional embodiment of the present invention, after receiving the group of photos, the meter reading platform performs image recognition on the group of photos, selects at least one target photo from the group of photos, obtains a feature value of the group of photos, and sends the feature value to the meter reading terminal.

In an optional embodiment of the present invention, performing image recognition on the group of photos to obtain feature values of the group of photos includes:

using an image processing algorithm to distinguish different features of the same or multiple feature areas of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo. The image processing algorithms herein include, but are not limited to, the following image recognition algorithms: color histogram algorithm, gray histogram algorithm, black pixel algorithm, etc.

Optionally, the meter reading terminal is further configured to take multiple groups of photos according to the characteristic values and transmit the multiple groups of photos to the meter reading platform after receiving the characteristic values issued by the meter reading platform, or select at least one target photo from the multiple groups of photos according to the characteristic values and transmit the target photo to the meter reading platform.

Specifically, the system according to the embodiment of the invention is composed of a meter reading terminal with wireless transmission capability and a meter reading platform capable of performing feature selection and identification, and a set of expert systems meeting the requirements are realized for the multi-screen electric meter reading and the target photo selection and under the condition that the types of phenotypes on the market are complex.

Wherein, meter reading terminal includes: the camera and the wireless transmission module can shoot a picture to be read, upload data to the meter reading platform through the wireless module and receive configuration sent by the meter reading platform; the configuration here may include: the shooting times, the shooting intervals, the characteristic values of the target photos and the like;

the meter reading platform mainly has the functions of receiving the photos uploaded by the terminal, selecting the characteristics of the target screen photos, selecting the target screen photos, displaying the recognition results and interacting with the terminal through issuing configuration.

The meter reading expert system mainly has the following three characteristics: the terminal is combined with a cloud end of platform interaction; a library of algorithms for different phenotypes, different characteristics; the terminal has edge computing capability; the meter reading expert system is introduced in combination with the three characteristics.

In the embodiment of the invention, the terminal takes a group of photos according to a certain number of times of taking photos and a certain photo interval, so as to ensure that the group of photos includes each screen of the multi-screen meter, generally, the number of times of taking photos and the photo interval cover a jump cycle (that is, the multi-screen meter starts from one screen and is switched to the screen again), and the group of photos are uploaded to the meter reading platform;

selecting the characteristics and the target photos for distinguishing the group of photos from the uploaded group of photos through a meter reading platform, wherein the platform can select the target photos when receiving a new group of photos through an image recognition algorithm and issue characteristic values (including characteristic area coordinates and characteristic values of the target photos) of the group of photos to a terminal;

after receiving the characteristic values issued by the platform, the terminal can select to take multiple groups of pictures each time and upload the pictures to the platform, and the platform selects the target picture, or only upload the target picture after the terminal selects the target picture.

Based on the interaction mode, a series of functions of photographing, uploading, feature selection and feature identification can be realized.

The target screen selection method based on feature recognition and the description of the algorithm library are as follows:

the target screen selection based on the feature recognition is to use an image recognition technology to distinguish different features of the same or multiple feature positions of different screens and select a photo desired to be displayed by a client.

As shown in fig. 2, the characteristic area of a group of photographs (including three photographs) is a box portion, and the different screens are distinguished by three lights being lit with the letter A, B, C. Therefore, it is sufficient to determine whether or not the corresponding lamp is turned on by the image recognition technology. The lighting position is judged by taking two methods of a color histogram and the number of black pixels as examples.

The color histogram is that the RGB color space or the gray scale space correspondingly takes values of 0-255, the horizontal axis is taken as the horizontal axis, and the vertical axis is the number of pixel points with corresponding values in the coordinate range of the selected picture. The eigenvalue of the region can be represented by a vector a (a0, a1, A2, …, Ai, …, a255), and Ai represents the number of pixels in the region corresponding to the color space value i. The A may be used as a feature vector to determine whether the area is in accordance with expectations, and may be a color histogram (RGB) or a gray histogram, and the on/off of the lamp may be determined by the difference of the histograms when the lamp is on or off.

As shown in fig. 3, the number of black pixels is changed into a binary image by performing graying and binarization processing on the image, and the number of black pixels in the image is determined to distinguish whether the lamp is on or off, and the next image is the processing result of lamp a and lamp B, C when lamp a is on and after graying and binarization:

in fig. 3, the black pixel of lamp a is approximately: 950; the B lamp black pixel is approximately: 1400; the C lamp black pixel is approximately: 1440; it can be judged that a is different from B, C.

The meter reading platform stores different algorithms for different feature identification, the feature is identified by adapting to a proper feature identification algorithm based on the selection of the feature, and the identification algorithm can be optimized according to the feedback of the identification result. The feature recognition algorithm corresponds to different feature information, including but not limited to methods such as "color histogram", "black pixel" and the like mentioned herein, and some basic image processing methods (graying, binarization, expansion, corrosion and the like); the matching of the features to be recognized and the feature recognition algorithm can be dynamically adjusted according to the feedback of the recognition result, the consumed computation amount is limited, and the method can be operated in a meter reading terminal with limited resources;

as shown in fig. 4 and 5, the selection interface for meter reading platform features is shown, in the feature selection interface in the above figure, several keywords, i.e. objects, actions, and features, may be used to describe the difference between one target screen and other screens.

The JSON format can be used to describe the following:

{

object: { characters, lamps }

The actions are as follows: { Presence/absence, opening/closing }

Is characterized in that:

{

the text content is as follows: { "Total" }

Color: { black > 30%, yellow ≦ 30% }

Shape: { circle, line }

}

}

In particular to the example, the lamp can be simply described as:

{

object: lamp with a light source

The actions are as follows: open and close

Is characterized in that:

{

color: yellow colour

Shape: round (T-shaped)

}

}

According to the selected characteristics, the corresponding algorithm can be selected to select the photos, and the characteristic value of the algorithm is issued to the terminal, so that the terminal can select the target photos at the edge side based on the characteristic value and the algorithm.

The embodiment of the invention can also carry out interaction through a wireless transmission technology, the meter reading terminal receives the characteristic value, the shooting times and the shooting interval which are sent by the meter reading platform, selects a locally selected target photo or a group of photos to upload, and the meter reading platform dynamically adjusts and optimizes the characteristic value and the characteristic recognition algorithm according to the target photo uploaded by the meter reading terminal; the meter reading terminal is used for reading the multi-screen electric meters, but the terminal has certain edge computing capacity, the platform performs feature recognition, an expert system of terminal cloud interaction is not limited to the terminal, the terminal can also be used for other platforms to perform feature selection or recognition based on data acquired by the terminal, and the algorithm can be operated in the application of the terminal.

The embodiment of the invention aims at the multi-screen multi-display electric meter without data transmission capability, and the meter reading can be realized by installing the terminal on the electric meter without any modification on the existing multi-screen electric meter to be read. Compare the ammeter that self possesses the long-range ability of uploading of data or through the scheme that infrared reading ammeter reading uploaded, instant photo to backstage of this scheme shooting ammeter, data credibility is higher.

In addition, the scheme can realize adaptation to different phenotypes and different characteristics, and meanwhile, based on edge computing capability of end cloud combination, transmission power consumption can be reduced, so that the cost of equipment is reduced.

As shown in fig. 6, an embodiment of the present invention further provides a multi-screen electric meter reading method applied to a meter reading terminal, where the method includes:

step 61, receiving the photographing times and the photographing intervals configured by the meter reading platform;

step 62, shooting a group of photos according to the shooting times and the shooting intervals, wherein the group of photos comprise each screen of the multi-screen table;

and 63, uploading the group of photos to a meter reading platform.

In an optional embodiment of the present invention, the number of shots and the shot interval cover a transition period of the multi-screen table.

In an optional embodiment of the present invention, the method for reading the multi-screen electric meters further includes:

step 64, receiving a characteristic value issued by the meter reading platform;

and 65, shooting a plurality of groups of photos according to the characteristic values and uploading the photos to the meter reading platform, or selecting at least one target photo from the plurality of groups of photos according to the characteristic values and then uploading the target photo to the meter reading platform.

The method of the meter reading terminal side in the embodiment of the present invention is the same as the meter reading terminal in the system, and all the implementation manners in the embodiment are applicable to the embodiment, and the same technical effect can be achieved.

An embodiment of the present invention further provides a meter reading terminal, including:

the receiving module is used for receiving the photographing times and the photographing intervals configured by the meter reading platform;

the shooting module is used for shooting a group of photos according to the shooting times and the shooting intervals, and the group of photos comprise each screen of the multi-screen table;

and the sending module is used for uploading the group of photos to a meter reading platform.

In an optional embodiment of the present invention, the number of shots and the shot interval cover a transition period of the multi-screen table.

In an optional embodiment of the present invention, the receiving module may further be configured to: receiving a characteristic value issued by the meter reading platform; the sending module is further used for shooting a plurality of groups of photos according to the characteristic values and uploading the photos to the meter reading platform, or selecting at least one target photo from the plurality of groups of photos according to the characteristic values and then uploading the target photo to the meter reading platform.

The meter reading terminal is a meter reading terminal corresponding to the method shown in fig. 6, and all implementation manners in the method are applicable to the embodiment of the meter reading terminal, and the same technical effect can be achieved.

As shown in fig. 7, an embodiment of the present invention further provides a multi-screen electric meter reading method applied to a meter reading platform, where the method includes:

step 71, sending the photographing times and the photographing interval configured for the meter reading terminal to the meter reading terminal;

step 72, receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

step 73, obtaining characteristic values of the group of photos;

and step 74, sending the characteristic value to the meter reading terminal.

Optionally, step 73 may include: using an image processing algorithm to distinguish different features of the same or a plurality of feature positions of different screens, selecting at least one target photo from the group of photos, and acquiring feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

The method of the meter reading platform side in the embodiment of the invention is the same as the meter reading platform in the system, and all the implementation manners in the embodiment are applicable to the embodiment and can achieve the same technical effect.

An embodiment of the present invention further provides a meter reading platform, including:

the configuration module is used for configuring the photographing times and the photographing intervals for the meter reading terminal;

the receiving module is used for receiving a group of pictures which are shot and sent by the meter reading terminal according to the shooting times and the shooting intervals; the set of photographs contains each screen of the multi-screen table;

the acquisition module is used for acquiring the characteristic values of the group of photos;

and the sending module is used for sending the characteristic value to the meter reading terminal.

Optionally, the obtaining module is specifically configured to use an image processing algorithm to distinguish different features of the same or multiple feature positions of different screens, select at least one target photo from the group of photos, and obtain feature values of the group of photos; the characteristic values include: the characteristic region coordinates and the characteristic value of the target photo.

The meter reading platform is a meter reading platform corresponding to the method shown in fig. 7, and all implementation manners in the method are applicable to the embodiment of the meter reading terminal, and the same technical effect can be achieved.

Embodiments of the present invention also provide a computer-readable storage medium including instructions that, when executed on a computer, cause the computer to perform the method as described above. All the implementation manners in the above embodiments are applicable to the embodiment, and the same technical effects can be achieved.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.