FIELD OF DISCLOSURE

The present disclosure relates to maintenance of industrial process plants.

Particularly, the present disclosure relates to online health monitoring and controlling of various equipment in industrial process plants.

DEFINITIONS

The expression "process plants" used hereinafter in this disclosure refers to plants and machinery /equipment thereof used in various industries including but not limited to steam systems, chemical, petrochemical, manufacturing, mineral processing, food, pharmaceutical, biotechnological, water treatment, waste treatment and the like.

The expression "users" used hereinafter in this disclosure refers to persons working in a process plant including but not' limited to plant operators, plant supervisors, maintenance personnel, maintenance team and the like.

These definitions are in addition to those expressed in the art.

BACKGROUND

Process plants are typically operated by employing both continuous and batch processes to ensure desired production. A process plant generally includes a large number of equipment interconnected together wherein different procedures involving multiple steps, ongoing continuously in time, aid in manufacturing of products. This regular use without the required maintenance leads to frequent breakdown of equipment used in process plants thereby reducing productivity and efficiency of the plant. Hence proper maintenance of the plant and equipment is required to ensure sustainable productivity and efficiency. Maintenance of the plant and equipment typically includes periodic inspections and repair or replacement of various sensors, mechanical parts, and the like; investigating and trouble shooting problems such as leaks, wear, failure to meet product specifications, mechanical failures of valves, pumps, compressors, sensors, and the like.

Proper maintenance of plant equipment can significantly reduce overall operating cost, thereby also boosting productivity and efficiency of the plant. Over the past years, maintenance has become more important for the process industry. From keeping the equipment in good operational condition to restoring it to a desired operating condition, the role of maintenance has gained much more prominence in plant operation. Typically users in process plants schedule maintenance activities in any one of the situations listed herein below. i) Failure of equipment - In such situations, maintenance is carried out by repairing, restoring or replacing equipment or components of the equipment. Generally equipment fail due to lack of routine / scheduled maintenance. ii) Perception derived from visual/audio/parametric feel of equipment - Typically, due to wear and tear, the performance of an equipment goes down. This causes abnormal variations in parameters which are typically sensed by users through either visual (eg: deflection), audio (eg: noise), or parametric (eg: pressure) indicators. In such situations, corrective actions are implemented prior to the actual failure of the equipment. This requires human intervention for continuous monitoring. iii) Periodic maintenance (Preventive maintenance) - This is a time-based maintenance wherein the equipment is taken off-line and inspected on a periodic basis. Based on visual inspection, repairs are made and the equipment is then placed back on-line. However this process can be very expensive as typically, replacing, overhauling or remanufacturing equipment or components of the equipment is done at fixed intervals regardless of their condition at that time and without accounting for any unscheduled maintenance activity that may have been performed therebetween.

These typical maintenance activities including others known in the art are inadequate on their own, forcing the process plant to shutdown temporarily, thereby reducing the productivity of the process plant and rendering the users helpless. Furthermore, users lack insight into the cause of failure and users. have different views regarding the maintenance approach. As a result users end up blaming each other rather than thinking through the issue and working together to resolve the issue.

There have been several endeavors to overcome these issues in the prior art systems. For instance, United States Patent No. 7088255 entitled "Health Monitoring Display. System for a Complex Plant" is directed towards equipment level health display in the form of color and index number. The system comprises sensors for sensing specified parameters in the plant, health monitoring means that determine health condition for the components of the plant from the sensed values, and a human machine interface to provide an indication of the health of the plant. However the system of the disclosure is limited to equipment level health; system level health is not indicated. Further the system of United States Patent No. 7088255 is unable to prioritize alerts and schedule activities. There is no provision to identify factors which contribute towards reducing equipment unavailability, and optimize planned and unplanned downtime. Also audio-visual help for guiding the maintenance and operation teams to minimize errors is unavailable.

Hence there is a need for a system which can help to achieve higher productivity by reducing maintenance downtime, increase: equipment availability by reducing unplanned downtime, schedule maintenance activities and optimize planned downtime, guide maintenance teams in repairing, restoring or replacing equipment or components of the equipment, immediately intimate maintenance teams of failure in any equipment or any component of the equipment of the process plant and a system which can monitor the health of the process plant continuously.

OBJECTS

Some of the objects of the present disclosure are aimed to ameliorate one or more problems of the prior art or to at least provide a useful alternative and are listed herein below.

An object of the system of the present disclosure is to monitor the health of a process plant continuously:

Another object of the system of the present disclosure is to achieve higher productivity by reducing maintenance downtime.

Another object of the system of the present disclosure is to increase equipment availability in a process plant.

Another object of the system of the present disclosure is to reduce unplanned downtime. Another object of the system of the present disclosure is to schedule maintenance activities of a process plant.

Another object of the system of the present disclosure is to optimize planned maintenance downtime of a process plant. ,

Another object of the system of the present disclosure is to guide maintenance teams in repairing, restoring or replacing equipment or components of the equipment of a process plant.

Another object of the system of the present disclosure is to send timely notifications to users of any failure in any equipment or any component of the equipment of a process plant.

Another object of the system of the present disclosure is to increase safety, reliability and efficiency of a process plant.

Other objects and advantages of the present disclosure will be more apparent from the following description which is not intended to limit the scope of the present disclosure.

SUMMARY

In accordance with an aspect of the present disclosure, there is provided a health monitoring system for a process plant comprising a plurality of sub systems and associated equipment, wherein the system comprises:

• at least one sensor associated with the at least one associated equipment, the sensor adapted to sense at least one parameter indicative of the health of the associated equipment and generate corresponding signals; • a processor communicating with the sensor, the processor adapted to read the signals and generate corresponding data; and

• a central computer communicating with the processor, the computer adapted to continuously monitor and diagnose the health of the process plant, the - computer implementing: ¹

^■ a diagnostic module adapted to evaluate the data to determine the health of the associated equipment and generate corresponding health diagnostic annunciations for the associated equipment based on a predetermined severity level of the health of the associated equipment, the diagnostic module further adapted to determine the health of the process plant based on the health of each of the associated equipment;

^■ a maintenance scheduler adapted to predict maintenance activities for the " process plant based on at least one of:

♦ a pre-scheduled maintenance activity of at least one of the associated equipment, and

♦ real time condition based maintenance of at least one of the associated equipment based on the evaluated and diagnosed health;

■ an analyzer adapted to analyze deviation of health, loss of production and efficiency of the process plant based on the diagnosed health;

^■ a sensor sustainability module adapted to determine the health of the at least one sensor and generate a corresponding sensor alert in the event that the at least one sensor provides an inconsistent measurement of the at least one parameter;

^■ an external communication module adapted to send electronic communication to at least one user based on at least one of the severity level of the health and the sensor alert; and

^■ a central user interface adapted to display at least one of the health diagnostic annunciations, output of the maintenance scheduler, output of the analyzer module and the sensor alert. Additionally, the system further comprises an optimizer adapted to optimize the predicted maintenance activity.

Again, the system further comprises at least one discrete user interface unit associated with each of the sub systems to display at least one of the health diagnostic annunciations, output of the maintenance scheduler, output of the analyzer module, and the sensor alert associated with the sub system.

Generally, the parameter is selected from the group consisting of current, voltage, Total Dissolved Solids (TDS), fluid flow, vibration levels, temperature and pressure.

Generally, the sensor is selected from the group consisting of current sensor, voltage sensor, Total Dissolved Solids (TDS) sensor, vibration sensor, temperature sensor, valve travel sensor, Flow Meter sensor and pressure sensor.

Typically, the diagnostic annunciations are at least one of audio and visual indicators.

Typically, the maintenance scheduler, the optimizer and the analyzer are user editable. -

Generally, the electronic communication is selected from the group consisting of emails, text messages, and voice calls.

Additionally, the central computer further implements an audio-visual interactive help module adapted to guide users to operate the process plant, operate each of the associated equipment and to perform maintenance activity.

In accordance with another aspect of the present disclosure, there is provided ¹ a method of monitoring the health of a process plant comprising a plurality of sub systems and associated equipment, wherein the method comprises the following steps:

• sensing at least one parameter indicative of the. health of the at least one associated equipment and generating corresponding signals;

• generating data corresponding to the signals;

• evaluating the data to determine the health of the associated equipment and generating corresponding health diagnostic annunciations for the associated equipment based on a predetermined severity level of the health of the associated equipment;

• determining the health of the process plant based on the health of each of the associated equipment;

• predicting maintenance activities for the process plant based on at least one of:

■ a pre-scheduled maintenance activity of the associated equipment, and

■ real time condition based maintenance of the associated equipment based on the evaluated and diagnosed health.

• analyzing deviation of health, loss of production and efficiency of the process plant based on the diagnosed health;

• determining the health of the at least one sensor associated with the at least, one associated equipment and generating a corresponding sensor alert in the event that the at least one sensor provides an inconsistent measurement of the at least one parameter;

• sending an electronic communication to at least one user based on at least one of the severity level of the health and the sensor alert; and

• displaying at least one of the health diagnostic annunciations, predicted maintenance activity, analyzed results and the sensor alert. The step of generating corresponding health diagnostic annunciations as described herein above includes the step of categorizing the severity of the health of the associated equipment into 'safety', 'production', and 'efficiency'.

The step of determining the health of the plant as described herein above includes at least one of the following steps:

■ calculating a minimum of the health of each of the associated equipment, and

■ calculating a critical path in the process plant.

The step of predicting maintenance activities as described herein above includes the step of optimizing the predicted maintenance activities for each of the equipment, based on prescheduled and real-time start and end date of the maintenance downtime.

Typically, the step of determining the health of each of the sensors and generating a corresponding sensor alert is based on scientific data associated with the sensor and sensed data.

The step of analyzing as described herein above comprises the step of converting the deviation in the health of each of the associated equipment into at least one of:

■ contribution of deviation in the health of each of the associated equipment to overall plant health deviation in terms of percentage, and

■ monetary equivalent of the deviation in the health.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The system and method of the present disclosure will now be described with the help of the accompanying drawings, in which: Figure 1 illustrates architecture of a health monitoring system of a typical process plant, in accordance with an embodiment of the present disclosure;

Figure 2 illustrates a system level flowchart of the health monitoring system of the present disclosure;

Figure 3 illustrates an equipment level flowchart of the health monitoring system of the present disclosure;

Figure 4 illustrates an exemplary flow chart of an approach to preventive maintenance of equipment in accordance with an embodiment of the present disclosure; and

Figure 5 illustrates a graphical representation of the equipment availability over a period of time in accordance with an embodiment of system of the present disclosure.

DETAILED DESCRIPTION

The system and method of the present disclosure will now be described with reference to the embodiments shown in the accompanying drawings. The embodiments do not limit the scope and ambit of the disclosure. The description relates purely to the examples and preferred embodiments of the disclosed method and its suggested applications.

The system herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known parameters and processing techniques are omitted so as to not unnecessarily obscure the embodiment herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiment herein may be practiced and to further enable those of skill in the art to practice the embodiment herein. Accordingly, the examples should not be construed as limiting the scope of the embodiment herein.

Reviewing the most likely ways that equipment of a process plant will fail is important to ensure that maintenance activities are planned and carried out accordingly. Maintenance activities also enhance plant operation. Thus rather than restoring Or trying to restore the equipment to its original performance, planning maintenance activities could better still be aimed at enhancing the process and performance of the process plant and the equipment used in the plant.

The present disclosure envisages a system that continuously monitors the health of a process plant as well as the associated equipment of the process plant, to reduce unplanned down time and optimize planned downtime. The system of the present disclosure comprises sensors installed on the equipment of the process plant, data acquisition system, and signal conditioning system. The system uses sensor input data to perform diagnosis of the equipment of the process plant, arrive at alerts and define severity of the alerts. This helps to increase productivity, reduce maintenance time and decrease errors.

Figure 1 illustrates architecture of a health monitoring system (100) of a typical process plant, in accordance with an embodiment of the present disclosure. The system (100) comprises a central computer (101) that controls the entire health monitoring system (100) through a processor (102) connected to a plurality of sensors installed on the associated equipment of the process plant. The sensors sense various parameters indicative of the health of the associated equipment and generate corresponding signals. The central computer (101) continuously monitors and diagnoses the health of the process plant including its subsystems and associated equipment. In accordance with one embodiment, the processor (102) monitors a boiler (103) and a steam utilization plant (109). Different sensors are connected to the boiler (103) to sense/measure different types of parameters' in relation to the boiler (103) and generate corresponding signals. The sensors connected to the boiler (103) typically comprise a current/voltage sensor to measure power consumption and provide phase imbalance of electric motors in boiler (103) which can be displayed typically on a power meter (104), a Total Dissolved Solids (TDS) sensor (105), a vibration sensor to sense the vibration of the boiler which is typically displayed on a vibration meter (106), a bearing temperature sensor (107) and a valve travel sensor (108). Various sensors are also connected to the steam utilization plant (109) to sense/measure different types of parameters in relation ^: to the packaging plant (109) and generate corresponding signals. The sensors connected to the steam utilization plant (109) typically comprise a Flow Meter sensor (110), a temperature sensor (111), a TDS sensor (112), a valve travel sensor (113) and a pressure sensor (114).

The signals generated by the sensors are transferred to the processor (102) wherein the signals are converted to corresponding data. Thereafter the data transferred to the central computer (101) wherein a plurality of modules (not shown) are implemented to continuously monitor and diagnose the health of the process plant including its subsystems and associated equipment. The modules " include, but are not limited to, a diagnostic module, a maintenance scheduler, an optimizer, an analyzer, a sensor sustainability module, an external communication module and a central user interface. The diagnostic module evaluates the data to determine the health of the. associated equipment and generate corresponding health diagnostic annunciations for the associated equipment based on a predetermined severity level of the health of the associated equipment. The health diagnostic annunciations are typically audio/visual alerts/indicators. The diagnostic module further determines the health of the process plant based on the health of each of the associated equipment. The maintenance scheduler predicts a maintenance activity for the process plant based either on a pre-scheduled maintenance activity bf the associated equipment or on real time condition based maintenance of the associated equipment based on the evaluated and diagnosed health or both. The optimizer further optimizes the predicted maintenance activity based on prescheduled and real-time start and end date of the maintenance downtime. The analyzer analyzes the deviation of health, loss of production and efficiency of the process plant based on the diagnosed health. The sensor sustainability module determines the health of the sensors and generates a corresponding sensor alert when a sensor provides inconsistent measurement of the parameters. The external communication module sends an electronic communication to users based either on the severity level of the health or on the sensor alert or both, wherein the electronic communication includes emails/text messages/voice calls. The central user interface displays the health diagnostic annunciations, output of the maintenance scheduler, output of the analyzer module, and the sensor alerts. The maintenance scheduler, the optimizer and the analyzer are user editable via the user central interface. Additionally, the system (100) includes individual user interface units for users in different areas of the process plant. A super-user acknowledges and authenticates maintenance activities initiated and completed by individual users from individual user interface units.

Figures 2 and 3 illustrate a system level flowchart of the health monitoring system of the present disclosure and equipment level flowchart the health monitoring system of the present disclosure respectively. The health of each individual subsystem and the associated equipment is translated to overall plant health using the equation,

wl * El + w2 * E2 + wn * En,

wherein, wl, w2...wn denote weightage factors for individual associated equipment and :

El, E2...En denote health of each individual associated equipment.

The method implemented by the health monitoring system, in accordance with an embodiment of the present disclosure, includes the following steps:

• sensing parameters that are indicative of the health of the associated equipment and generating corresponding signals;

• generating data corresponding to the signals;

• evaluating the data to determine the health of the associated equipment and generating corresponding health diagnostic annunciations for the associated equipment based on a predetermined severity level of the health of the associated equipment, wherein the severity is categorized into 'safety', 'production', and 'efficiency' and the annunciations include audio/visual indicators;

• determining the health of the plant based on the health of each of the associated equipment by either calculating a minimum of the health of each of the associated equipment or calculating a critical path in the plant or both;

• predicting a maintenance activity for the plant based either on a pre- scheduled maintenance activity of the associated equipment or on real time condition based maintenance of the associated equipment based on the evaluated and diagnosed health or both, and further optimizing the predicted maintenance activity based on prescheduled and real-time start and end date of downtime; • analyzing deviation of health, loss of production and efficiency of the plant based on the diagnosed health;

• determining health of the sensors installed on the associated equipment of the process plant and generating a corresponding sensor alert when a sensor provides inconsistent measurement of parameters indicative of the health of the equipment;

• sending an electronic communication to users based on either the severity level of the health or sensor alert or both; and

• displaying the health diagnostic annunciations, predicted maintenance activity, analyzed results and sensor alerts.

The health monitoring system of the present disclosure include features, but are not limited to those listed herein below.

• A new approach for preventive maintenance of equipment of a process plant by using both fixed time and real time condition based health evaluation. Maintenance of equipment of the process plant is evaluated based on a

^* minimum of i) scheduled maintenance time as stated in the guidelines of Original Equipment Manufacturer (OEM) / Standard Operating Procedure (SOP), and ii) operating condition health evaluation based on predefined parameters such as pressure, temperature, vibration, current, and the like. Figure 4 illustrates an exemplary flow chart of the aforementioned approach of preventive maintenance. As shown in figure 4, a user is required to take corrective action if either 2.5 months from an earlier maintenance activity has lapsed or if the pressure increases to 100 mmWC. Thus, if the pressure increases to 100 mmWC even before 2.5 months, the user can take action without waiting for the scheduled 2.5 months to complete.

• Categorization of severity of health of several different equipment in the process plant by segregating severity alerts into safety, production and efficiency. Equipment in a process plant perform either or all of the aspects in relation to safety, production and efficiency parameters ^' . These parameters help to determine the health of each equipment in the plant. This helps users to prioritize maintenance activities. In case there are three alerts at the-same time, ¹ in traditional systems, users are required to decide which alert is urgent thereby leading to possibly erratic decisions. In accordance with the health monitoring system of the present disclosure, alerts are categorized under safety, production and efficiency parameters which help in prioritizing and . making the decision process quick and unbiased.

• Conveying priority and importance of maintenance requirement of the equipment through an equipment level input to the users through visual and numeric indicators. The■ indicator indicates safety/production/efficiency parameters to predict health of each equipment typically by,

^■ a color indicator with three colors green/yellow/red, to indicate health status such as OK/deviating/not OK, and

^■ health number from 0 to 100% for indicating .severity to decide maintenance priority and also for color blind users.

• System level health evaluation and indication by displaying color and number to convey severity and priority of individual equipment on overall system performance. Health of individual equipment is used to derive the health of the process plant.

■ In accordance with one embodiment, the equipment of the process plant are connected in series. Accordingly, the health of the process plant is a minimum of the health of all the equipment in the process plant.

■ In accordance with another embodiment, the equipment of the process plant are connected in parallel. Accordingly, health of the process plant is derived based on a critical path in the plant.

• Optimizing planned downtime of equipment of process plants after entering start and end date of scheduled downtime in a module typically referred to as a SmartSchedule module. This helps users to identify which equipment needs to be maintained in a given time frame. This in turn helps to optimize scheduled maintenance. Figure 5 illustrates a graphical representation of equipment availability over a period of time, in accordance with an embodiment of the system of the present disclosure. This representation is indicative of the availability of equipment and clearly indicates which equipment can be taken for maintenance. Typically, all equipment have maintenance timelines. When any equipment is scheduled to undergo maintenance activity or has to be shut down for few days, the SmartSchedule module will suggest a few more equipment with impending down time which can be scheduled for maintenance. Users need to enter the start and end date of proposed shutdown in the SmartSchedule module whereupon the SmartSchedule module will suggest additional equipment. This will enable reduction in the overall downtime in a year since multiple equipment can be scheduled in the same time frame instead of separate down times for each equipment.

Analyzing loss of production and efficiency based^ on various alerts generated during operation of the process plant by a module typically referred to as an Impact Analysis module. One of the reasons for disputes between users is unavailability of scientific information about the contribution and weightage of various parameters that contribute towards reduced productivity. This is evaluated by using fundamental laws and comparing them with ideal situations, such as effect of actual pressure and temperature on increase in process time. This helps users to understand issues in an unbiased manner and resolve them peacefully. Impact analysis converts the deviation in the health of all the equipment into,

■ contribution of the deviation in health of each associated equipment to overall process health deviation in terms of percentage (%), and

■ monetary equivalent of health deviation. Both these parameters help users to understand the cause of process health deviation with impact and device corrective strategy.

Audio- Visual interactive help for enhancing skills of users, reducing errors by users and storing and providing a scanned copy of the operation manual provided by the OEMs. Typically, process plants have semi skilled, frequently changing maintenance teams. This increases either downtime or increases errors in maintenance activities. Also over a period of time, manual copies provided by OEMs and SOPs for maintenance are lost. All these issues are resolved by providing an audio-visual interactive help module. For instance, the audio-visual interactive help module includes a video of how to clean fans.

Individual display for users in different areas of the process plant and a central display for a super-user to monitor and track the entire process.

Centralized authentication and acknowledgement of maintenance activities by a super-user for actions initiated and completed by individual users from individual displays.

Sensor and system self-sustainability feature to check and alert the health of sensors installed on the equipment. This feature intimates the users to repair/calibrate/replace sensors and thereby increase reliability of the system. This is accomplished by evaluating the health of sensors in the system by, ■ Use of both sensors and sensed data: in case a sensor shows faulty reading, the users will detect the error by evaluating time since last operation or noise in the area. This method of detection is included in the health monitoring system of the present disclosure to accurately predict faulty parameters and indicate accordingly. Table below shows this approach, What Causes Breakdown

How Safety Production Efficiency

to Science

Prevent Sensed Data

• Functional relation between parameters: two different parameters, such as pressure and temperature, being monitored may exhibit some relation. This can be used to track the working condition of each sensor and generate an alert accordingly.

• Email and sms alerts to inform severity of alerts to the users and to inform the higher authority in case severity crosses a threshold level for taking necessary action.

• Ability to schedule and streamline maintenance activities by sending information to suppliers and contractors through email/sms thereby reducing downtime.

• Provision to define new and edit the existing maintenance standard operating procedures (SOP' s) and also enter new ones over a period of time.

• Failure evaluation of equipment of process plants such as,

^■ Pressure Reducing Valve (PRV) and Flow . Control Valve (FCV)/ Temperature Control Valve (TCV) - diaphragm failure characteristics,

^■ Trap leakage detection from temp & level characteristics,

^■ safety equipment failure characteristics - Induced Draft (ID)/ Forced Draft (FD) fan, furnace melting, water drum evaluation, and

■ Economizer/ Air Pre-Heater (APH) leakage detection.

Thus, the health monitoring system of the present disclosure continuously monitors the health of a process plant as well as equipment of the process plant to reduce unplanned down time and optimize planned downtime thereby increasing productivity and efficiency of the process plant. .

TECHNICAL ADVANCEMENTS AND ECONOMIC SIGNIFICANCE

i ■ i

The technical advancements offered by the system and method of the present disclosure include the realization of:

• monitoring the health of a process plant continuously;

• achieving higher productivity by reducing the maintenance downtime;

• increasing the equipment availability of a process plant by reducing unplanned downtime;

• scheduling maintenance activities of a process plant;

• optimizing planned maintenance downtime of a process plant;

• guiding maintenance teams in repairing, restoring or replacing the equipment or components of the equipment of a process plant; and

• notifying maintenance teams of any current and/or possible failure in any equipment or any component of the equipment of a process plant, in a timely manner.

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not exclusion of any other element, integer or step, or group of elements, integers or steps.

Any discussion of documents, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have - been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.