阅读说明：本技术 保护光纤线路的方法、系统及存储介质 (Method, system and storage medium for protecting optical fiber circuit ) 是由 程昊 孙浩 高雷 于 2021-07-08 设计创作，主要内容包括：本发明公开了一种保护光纤线路的方法、系统以及存储介质,所述方法包括：控制板获取心跳信息；所述控制板对所述心跳信息进行故障分析,获取分析结果；其中,所述控制板对故障时间设置阈值；所述控制板根据所述分析结果,控制所述光纤线路的切换状态。本发明的技术方案,利用光纤线路保护心跳网络实现多种故障检测,并设置了故障时间的阈值,可以实现灵活应对多种需求；实现了同时对多故障的处理,增强了系统的鲁棒性。(The invention discloses a method, a system and a storage medium for protecting an optical fiber circuit, wherein the method comprises the following steps: the control panel acquires heartbeat information; the control panel carries out fault analysis on the heartbeat information to obtain an analysis result; wherein the control board sets a threshold value for the failure time; and the control board controls the switching state of the optical fiber circuit according to the analysis result. According to the technical scheme, the optical fiber line is used for protecting the heartbeat network to realize multiple fault detections, and the threshold value of fault time is set, so that multiple requirements can be flexibly met; the method and the device realize the simultaneous processing of multiple faults and enhance the robustness of the system.)

1. A method of protecting an optical fiber line, comprising:

the control panel acquires heartbeat information;

the control panel carries out fault analysis on the heartbeat information to obtain an analysis result; wherein the control board sets a threshold value for the failure time;

and the control board controls the switching state of the optical fiber circuit according to the analysis result.

2. The method of claim 1, wherein the control panel obtains heartbeat information, comprising:

the control panel acquires first heartbeat information sent by a service processing panel, wherein the first heartbeat information comprises state information of receiving optical fiber information of a port at the link side of the service processing panel;

the control board acquires second heartbeat information sent by the optical fiber circuit protection board, wherein the second heartbeat information comprises state information of a port of the optical fiber circuit protection board for receiving the optical fiber information and state information of the dial switch.

3. The method of claim 2, wherein the control board performs fault analysis on the heartbeat information to obtain an analysis result, and the fault analysis comprises:

the control panel extracts the heartbeat information to obtain an extraction result;

and the control panel performs fault analysis on the extraction result to obtain an analysis result.

4. The method of claim 3, wherein the control board sets a threshold for a time to failure comprising:

when the fault time does not exceed a threshold value, the control board controls the dial switch to execute a first switching action; and when the fault time exceeds a threshold value, the control board controls the dial switch to execute a second switching action.

5. The method of claim 4, wherein the failure time is obtained by:

determining a starting time;

acquiring the fault time according to the difference value between the current time of the fault and the starting time; wherein if the failure time exceeds the threshold, the control board updates the first switching action to be executed currently to the second switching action.

6. The method of claim 5, wherein the fault comprises at least one of:

the business processing board is pulled out or reset; a power failure occurs; a switch channel failure inside the device; the equipment is abnormally high-temperature; the control panel is not on-line; the optical fiber circuit protection board detects external link abnormity; the deviation between the total output and the total input of any link exceeds a preset value; the port of the optical fiber circuit protection board receives optical fiber information normally, and the port of the service processing board outputs optical fiber information abnormally.

7. The method of claim 6, wherein the control board controls the switching state of the optical fiber circuit according to the analysis result, comprising:

the analysis result comprises a plurality of faults;

determining a plurality of switching actions of the dial switch according to a plurality of faults;

carrying out priority judgment on the switching actions and determining the priorities of the switching actions;

and the control panel controls the actual switching action of the dial switch according to the priority.

8. The method of claim 7, wherein the switching action comprises:

the method comprises the following steps of optical protection bypass, electric protection bypass, turn-off access and serial access; the priority of the switching action is from high to low as: and the optical protection bypass, the electric protection bypass, the turn-off access and the serial access are connected.

9. A system for protecting a fiber optic line, comprising:

the control system comprises at least one control board, a power supply and a power supply, wherein the control board comprises a main control board and an auxiliary control board, and the main control board is in communication connection with the auxiliary control board;

at least one optical fiber circuit protection board, wherein the optical fiber circuit protection board is in communication connection with the control board;

and the service processing board is in communication connection with the control board and the optical fiber circuit protection board respectively.

10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the method according to any one of claims 1 to 8.

Technical Field

The present invention relates to a method, a system and a storage medium for protecting an optical fiber line, and belongs to the technical field of optical fiber lines.

Background

When equipment is connected in series in an optical fiber circuit, the optical fiber circuit is protected by optical fiber circuit protection equipment; optical devices such as optical switches and optical detectors are usually used to form an optical fiber line protection device with high reliability. When equipment breaks down, the optical fiber line protection equipment can shield the service processing board card of the series equipment, so that the flow is directly transmitted to downstream equipment through the protection equipment, and the flow is ensured not to be lost. However, only the hardware equipment is far from enough, and the software needs to be realized by corresponding software, and the software system is responsible for fault judgment and issuing of specific optical fiber line protection switching commands, so that the hardware equipment is operated to realize the specific optical fiber line protection function.

In the existing scheme, a mode that the whole machine only uses one set of heartbeat network to transmit information is adopted, however, the problem that the related information required by the protection of the optical fiber circuit cannot be collected due to abnormal heartbeat procedures often occurs in the mode, and further misjudgment and wrong optical fiber circuit switching are generated. Meanwhile, in the existing scheme, the fault detection object is incomplete, all possible fault conditions are not covered, and a fault switching threshold value is not generally set, so that the state of an optical fiber circuit is switched immediately after a fault occurs, the fault problem is not favorably positioned or the customer requirements under certain conditions are not met, and a problem processing method for simultaneously generating multiple faults is often lacked in the existing scheme.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, an object of the present invention is to provide a method, a system and a storage medium for protecting an optical fiber line, which can implement multiple kinds of fault detection and flexibly meet multiple requirements.

In order to solve the above technical problem, an embodiment of the present invention provides the following technical solutions:

a method of protecting an optical fiber line, comprising:

the control panel acquires heartbeat information;

the control panel carries out fault analysis on the heartbeat information to obtain an analysis result; wherein the control board sets a threshold value for the failure time;

and the control board controls the switching state of the optical fiber circuit according to the analysis result.

Optionally, the acquiring, by the control board, heartbeat information includes:

the control panel acquires first heartbeat information sent by a service processing panel, wherein the first heartbeat information comprises state information of receiving optical fiber information of a port at the link side of the service processing panel;

the control board acquires second heartbeat information sent by the optical fiber circuit protection board, wherein the second heartbeat information comprises state information of a port of the optical fiber circuit protection board for receiving the optical fiber information and state information of the dial switch.

Optionally, the performing, by the control board, fault analysis on the heartbeat information to obtain an analysis result includes:

the control panel extracts the heartbeat information to obtain an extraction result;

and the control panel performs fault analysis on the extraction result to obtain an analysis result.

Optionally, the setting, by the control board, a threshold value for the failure time includes:

when the fault time does not exceed a threshold value, the control board controls the dial switch to execute a first switching action; and when the fault time exceeds a threshold value, the control board controls the dial switch to execute a second switching action.

Optionally, the failure time is obtained by:

determining a starting time;

acquiring the fault time according to the difference value between the current time of the fault and the starting time; wherein if the failure time exceeds the threshold, the control board updates the first switching action to be executed currently to the second switching action.

Optionally, the fault includes at least one of:

the business processing board is pulled out or reset; a power failure occurs; a switch channel failure inside the device; the equipment is abnormally high-temperature; the control panel is not on-line; the optical fiber circuit protection board detects external link abnormity; the deviation between the total output and the total input of any link exceeds a preset value; the port of the optical fiber circuit protection board receives optical fiber information normally, and the port of the service processing board outputs optical fiber information abnormally.

Optionally, the controlling board controls the switching state of the optical fiber line according to the analysis result, including:

the analysis result comprises a plurality of faults;

determining a plurality of switching actions of the dial switch according to a plurality of faults;

carrying out priority judgment on the switching actions and determining the priorities of the switching actions;

and the control panel controls the actual switching action of the dial switch according to the priority.

Optionally, the switching action includes:

the method comprises the following steps of optical protection bypass, electric protection bypass, turn-off access and serial access; the priority of the switching action is from high to low as: and the optical protection bypass, the electric protection bypass, the turn-off access and the serial access are connected.

An embodiment of the present invention further provides a system for protecting an optical fiber line, including:

the control system comprises at least one control board, a power supply and a power supply, wherein the control board comprises a main control board and an auxiliary control board, and the main control board is in communication connection with the auxiliary control board;

at least one optical fiber circuit protection board, wherein the optical fiber circuit protection board is in communication connection with the control board;

and the service processing board is in communication connection with the control board and the optical fiber circuit protection board respectively.

Embodiments of the present invention also provide a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method as described above.

The embodiment of the invention has the following technical effects:

according to the technical scheme, the optical fiber line is used for protecting the heartbeat network to realize multiple fault detections, and the threshold value of the fault time is set, so that multiple requirements can be flexibly met; the method and the device realize the simultaneous processing of multiple faults and enhance the robustness of the system.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic flow chart of a method for protecting an optical fiber circuit according to an embodiment of the present invention;

FIG. 2 is a block diagram of a method of protecting a fiber optic line provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating a principle of prior execution of a handover operation according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a system for protecting an optical fiber line according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

Bypass mentioned in the invention: a bypass function.

As shown in fig. 1, an embodiment of the present invention provides a method of protecting an optical fiber line, including:

step S1: the control panel acquires heartbeat information;

specifically, the control panel comprises a main control panel and an auxiliary control panel, and when the main control panel is disconnected or stops working, the auxiliary control panel automatically takes over the main control panel to work; wherein, the control panel is continuously receiving heartbeat information in a circulating way.

Step S2: the control panel carries out fault analysis on the heartbeat information to obtain an analysis result; wherein the control board sets a threshold value for the failure time;

step S3: and the control board controls the switching state of the optical fiber circuit according to the analysis result.

According to the embodiment of the invention, the optical fiber line is utilized to protect the heartbeat network to realize multiple fault detections, and the threshold value of the fault time is set, so that multiple requirements can be flexibly met; the method and the device realize the simultaneous processing of multiple faults and enhance the robustness of the system.

In an optional embodiment of the present invention, in step S1, the acquiring, by the control board, heartbeat information includes:

step S11: the control panel acquires first heartbeat information sent by a service processing panel, wherein the first heartbeat information comprises state information of receiving optical fiber information of a port at the link side of the service processing panel;

specifically, the service processing board monitors the state of the port at the link side for receiving the optical fiber information, packages the monitored state information in real time to obtain first heartbeat information, and sends the first heartbeat information to the control board.

Step S12: the control board acquires second heartbeat information sent by the optical fiber circuit protection board, wherein the second heartbeat information comprises state information of a port of the optical fiber circuit protection board for receiving the optical fiber information and state information of the dial switch.

Specifically, the optical fiber circuit protection board monitors the state of receiving optical fiber information at the port of the optical fiber circuit protection board, packages the monitored state information in real time to obtain second heartbeat information, and sends the second heartbeat information to the control board;

the dial switch is arranged on the optical fiber circuit protection board, and sends a control instruction to the dial switch through the control board to control the switching action of the dial switch.

According to the embodiment of the invention, the control panel is used for collecting the state information of the optical fiber circuit protection board and the service processing board, so that a coping strategy can be generated in time for the faults of the optical fiber circuit protection board and the service processing board; meanwhile, a plurality of faults can be detected and judged simultaneously.

In an optional embodiment of the present invention, in step S2, the performing, by the control board, fault analysis on the heartbeat information to obtain an analysis result includes:

step S21: the control panel extracts the heartbeat information to obtain an extraction result;

specifically, the control panel extracts information from the acquired heartbeat information and filters out unnecessary information.

Step S22: and the control panel performs fault analysis on the extraction result to obtain an analysis result.

According to the embodiment of the invention, the control panel extracts the heartbeat information to acquire the state information for fault analysis, and performs fault analysis on the state information for fault analysis to acquire the type of the fault, so that the simultaneous detection of multiple faults is realized, and the fault processing efficiency is improved.

In an alternative embodiment of the present invention, in step S22, the setting, by the control board, a threshold value for the failure time includes:

in step S221, when the fault time does not exceed the threshold, the control board controls the dial switch to perform a first switching operation; and when the fault time exceeds a threshold value, the control board controls the dial switch to execute a second switching action.

According to the embodiment of the invention, the switching action of the dial switch is accurately controlled by setting the fault time threshold, and the misjudgment and the execution of the wrong switching action are avoided.

In an alternative embodiment of the present invention, in step S221, the failure time is obtained as follows:

step S2211: determining a starting time;

step S2212: acquiring the fault time according to the difference value between the current time of the fault and the starting time; wherein if the failure time exceeds the threshold, the control board updates the first switching action to be executed currently to the second switching action.

Specifically, the method for calculating the fault time includes that a change time point from no fault to occurrence of a certain fault is used as an initial time corresponding to the certain fault, whether the certain fault exists at present is judged in each cycle, if the certain fault exists, the initial time of the certain fault is subtracted from the current time, and an obtained difference value is the certain fault time; and if the fault is recovered, clearing the fault time, and recalculating the fault starting time when the fault occurs next time.

And if the failure time exceeds the time threshold, correspondingly updating the switching action to be executed currently.

According to the embodiment of the invention, the switching action of the dial switch can be accurately controlled by calculating the fault time, so that the error of the switching action is further avoided.

In an alternative embodiment of the present invention, the fault includes at least one of the following:

the business processing board is pulled out or reset; a power failure occurs; a switch channel failure inside the device; the equipment is abnormally high-temperature; the control panel is not on-line; the optical fiber circuit protection board detects external link abnormity; the deviation between the total output and the total input of any link exceeds a preset value; the port of the optical fiber circuit protection board receives optical fiber information normally, and the port of the service processing board outputs optical fiber information abnormally.

According to the embodiment of the invention, the control panel can simultaneously detect the multiple faults according to the extracted state information, the fault detection content is sufficient, all possible fault conditions can be covered, the fault problem can be accurately positioned, and the requirements of customers are met.

With reference to fig. 2, the above embodiment can be implemented by the following implementation:

the control board takes a main control board as an example:

the main control board receives heartbeat information protected by the optical fiber circuit;

extracting information and carrying out fault analysis;

judging whether a fault occurs according to the result of the fault analysis, and if the fault does not occur, returning to the step 1); if the fault occurs, judging whether the fault time exceeds a threshold value, if not, updating a control instruction of the main control board into a switching action instruction corresponding to the fault time which does not exceed the threshold value; if yes, updating the control command of the main control board into a switching action command corresponding to the fault time exceeding the threshold value.

And after the dial switch executes the switching action, returning to the step 1).

In an alternative embodiment of the present invention, in step S3, the controlling board controls the switching state of the optical fiber circuit according to the analysis result, including:

step S31: the analysis result comprises a plurality of faults;

specifically, if a plurality of faults exist in the extraction result, the plurality of faults can be detected at the same time.

Step S32: determining a plurality of switching actions of the dial switch according to a plurality of faults;

specifically, the control board sends the switching action of the dial switch corresponding to the fault type to the dial switch according to the determined fault type.

Step S33: carrying out priority judgment on the switching actions and determining the priorities of the switching actions;

specifically, since a plurality of failures correspond to a plurality of switching actions, it is necessary to perform priority comparison on the execution of the plurality of switching actions.

Step S34: and the control panel controls the actual switching action of the dial switch according to the priority.

Specifically, the to-be-executed switching action with the highest priority is selected, and the action is determined as the action to be executed finally.

The embodiment of the invention realizes the judgment of a plurality of corresponding switching actions when a plurality of faults occur simultaneously, and judges the actual switching action which needs to be executed finally according to the priority of the switching action to be executed, thereby enhancing the robustness of the system.

In an alternative embodiment of the present invention, in step S33, the switching action includes:

step S331: the method comprises the following steps of optical protection bypass, electric protection bypass, turn-off access and serial access; the priority of the switching action is from high to low as: and the optical protection bypass, the electric protection bypass, the turn-off access and the serial access are connected.

With reference to fig. 3, specifically, 1) taking the main control board as an example, the state machine on the main control board performs state transition of the optical fiber line according to the current state and the final switching action to be executed obtained in the current cycle. The state machine on the main control board executes the output control command, and the state of the link on the optical fiber circuit protection board is controlled by the switching command issued by the state machine.

2) The state machine on the auxiliary control board is also in normal operation, and all the states are completely consistent with those on the main control board. Only the communication channel on the auxiliary control is not communicated, so that the switching command cannot be issued to the optical fiber circuit protection board; equivalent to the state machine on the auxiliary control board does not work; the auxiliary control board is used for providing a backup function.

3) The control panel compares the priorities of the to-be-executed switching actions corresponding to all faults detected in the cycle, selects the to-be-executed switching action with the highest priority, determines the switching action as the action to be executed finally, and updates the event corresponding to the switching action into the corresponding fault event;

as shown in fig. 3, 1) the dial switch executes the optical protection bypass action, and the last state of the optical fiber route is transferred to the optical protection bypass state; for example, the state is transferred from an electric protection bypass state, a cut-off access state or a serial access state to an optical protection bypass state;

2) when the dial switch executes the action of the electric protection bypass, the last state of the optical fiber line is transferred to the state of the electric protection bypass; for example, the state is switched from an off access state or a serial access state to an electric protection bypass state;

3) the dial switch executes the switch-off and switch-in actions, and the last state of the optical fiber line is transferred to a switch-off and switch-in state; such as transitioning from a tandem access state to an off access state.

According to the embodiment of the invention, all switching actions to be executed are determined according to the switching conditions corresponding to all faults, then the priority of the switching actions is judged, and finally the complete machine state machine is used for switching the optical fiber circuit, so that the optical fiber circuit protection is carried out on the series connection equipment.

As shown in fig. 4, an embodiment of the present invention further provides a system for protecting an optical fiber line, including:

the control system comprises at least one control board, a power supply and a power supply, wherein the control board comprises a main control board and an auxiliary control board, and the main control board is in communication connection with the auxiliary control board;

at least one optical fiber circuit protection board, wherein the optical fiber circuit protection board is in communication connection with the control board;

and the service processing board is in communication connection with the control board and the optical fiber circuit protection board respectively.

The number of the control board, the optical fiber circuit protection board and the service processing board can be preset as required, for example, two.

Specifically, all the service processing boards send heartbeat information for protecting the optical fiber line to the main control boards of all the control boards, and the content of the heartbeat information carries state information of receiving optical fibers at the link side ports of the service processing boards.

All the optical fiber circuit protection boards send heartbeat information of optical fiber circuit protection to all the main control boards, and the heartbeat information carries state information of receiving optical fibers and state information of the dial switch of the panel ports of the optical fiber circuit protection boards.

All the service processing boards send heartbeat information for protecting the optical fiber lines to all the optical fiber line protection boards, and the heartbeat information content carries state information of receiving optical fibers at the link side ports of the service processing boards. All control panels send optical fiber circuit protection heartbeats to all optical fiber circuit protection boards, and the heartbeats carry state information of the main control panel.

When the optical fiber circuit protection board detects that the main control board and the auxiliary control board cannot work normally, such as a disconnection, the optical fiber circuit protection board performs fault analysis according to the received state information of the receiving optical fiber at the link side port of the service processing board, acquires a switching action corresponding to the fault, judges the priority of the switching action, determines the switching action to be executed finally according to the priority, and updates an event corresponding to the switching action to a corresponding fault event.

The embodiment of the invention provides a special communication channel for transmitting the information required by protecting the optical fiber line, thereby protecting the optical fiber line of the network tandem connection equipment.

Embodiments of the present invention also provide a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method as described above.

In addition, other configurations and functions of the system according to the embodiment of the present invention are known to those skilled in the art, and are not described herein in detail to reduce redundancy.

It should be noted that the logic and/or steps represented in the flowcharts or otherwise described herein, such as an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.