Method and device for determining comprehensive preventive maintenance rate of ship equipment

Abstract

The invention discloses a method and device for determining the comprehensive preventive maintenance rate of ship equipment, and belongs to the field of ship equipment.The method comprises the steps that a state network of the ship equipment is obtained, the state network comprises a plurality of state transition processes of the ship equipment, and the state transition processes comprise transition from a first state to a second state, the first state and the second state are different states in a state network, and the state network comprises a preventive maintenance state; acquiring state data of the ship equipment; frequency analysis is carried out on time spent in each state transition process according to the state data, and cumulative distribution obeyed by the time spent in each state transition process is obtained; and determining the state transition rate of each state transition process according to the cumulative distribution obeyed by the time spent by each state transition process. According to the method, the comprehensive rate related to preventive maintenance of the ship equipment can be accurately calculated.

Description

Technical Field

[0001] The present disclosure relates to the field of ship equipment, and in particular to a method and device for determining a comprehensive rate of preventive maintenance of ship equipment. Background Art

[0002] The centralized and periodic maintenance of shipboard equipment is subject to both time and space constraints. For example, during a ship's voyage, it is difficult to carry out centralized and periodic maintenance of shipboard equipment due to factors such as the crew's maintenance skills, the availability of onboard maintenance facilities and equipment, and the maintenance space.

[0003] In order to simplify maintenance tasks and improve maintenance support efficiency, ship users and managers prefer to inspect ship equipment through preventive maintenance (dismantling the equipment and sending it to a repair shop on shore for centralized inspection) after the ship docks.

[0004] The comprehensive rate of preventive maintenance of ship equipment can reflect multiple rates related to preventive maintenance of ship equipment. It is necessary to accurately determine the comprehensive rate of preventive maintenance of ship equipment so that preventive maintenance of ship equipment can be accurately performed based on the comprehensive rate of preventive maintenance of ship equipment. Summary of the Invention

[0005] The present disclosure provides a method and apparatus for determining the comprehensive rate of preventive maintenance of ship equipment, which can accurately calculate the comprehensive rate related to preventive maintenance of ship equipment. The technical solution includes at least the following solutions: In a first aspect, a method for determining a comprehensive rate of preventive maintenance of ship equipment is provided, comprising: obtaining a state network of the ship equipment, the state network comprising a plurality of state transition processes of the ship equipment, the state transition process comprising a transition from a first state to a second state, the first state and the second state being different states in the state network, the state network comprising a preventive maintenance state; obtaining state data of the ship equipment; performing a frequency analysis on the time spent on each state transition process based on the state data to obtain a cumulative distribution of the time spent on each state transition process; and determining a state transition rate of each state transition process based on the cumulative distribution of the time spent on each state transition process.

[0006] Optionally, the state transition process includes transitioning from a preventive maintenance state to a sound state and from a preventive maintenance state to a serviceable state, and performing a frequency analysis on the time spent on each state transition process based on the state data to obtain a cumulative distribution of the time spent on each state transition process includes: obtaining a preventive maintenance strategy set, the preventive maintenance strategy set including preventive minor repairs, preventive medium repairs, and preventive major repairs; and performing a frequency analysis on the time spent on different preventive maintenance strategies based on the state data to obtain a cumulative distribution of the time spent on each preventive maintenance strategy.

[0007] Optionally, determining the state transition rate of each state transition process based on the cumulative distribution of the time spent in each state transition process includes: determining the state transition rate corresponding to each preventive maintenance strategy based on the cumulative distribution of the time spent in each preventive maintenance strategy; and determining the state transition rate of transitioning from the preventive maintenance state to the intact state and the state transition rate of transitioning from the preventive maintenance state to the serviceable state based on the state transition rate corresponding to each preventive maintenance strategy and the nested relationship between the preventive maintenance strategies.

[0008] Optionally, the state transition rate from the preventive maintenance state to the intact state is expressed by the following formula:

[0009] The state transition rate from the preventive maintenance state to the serviceable state is expressed by the following formula:

[0010] in, is the state transition rate from the preventive maintenance state to the intact state, is the state transition rate from the preventive maintenance state to the serviceable state, The probability of performing preventive minor repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after a preventive minor repair. The probability of conducting preventive repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive repairs. The probability of performing preventive overhauls on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive overhaul. is the state transition rate corresponding to preventive minor repairs, is the state transition rate corresponding to the preventive repair, is the state transition rate corresponding to preventive overhaul, 、 and It is determined according to the nested relationship between the preventive maintenance strategies.

[0011] Optionally, the probability of the ship equipment undergoing preventive minor repairs It is expressed by the following formula:

[0012] The probability of the ship equipment undergoing preventive maintenance It is expressed by the following formula:

[0013] The probability of the ship equipment undergoing preventive overhaul It is expressed by the following formula:

[0014] in, 、 The value of is related to the nested relationship between the preventive maintenance strategies, which includes: If a minor preventive repair is performed, a medium preventive repair must be performed. A preventive overhaul must be carried out after each preventive medium overhaul.

[0015] In the second aspect, a device for determining the comprehensive rate of preventive maintenance of ship equipment is also provided, including: a first acquisition module for acquiring a state network of ship equipment, the state network including multiple state transition processes of the ship equipment, the state transition process including a transition from a first state to a second state, the first state and the second state being different states in the state network, and the state network including a preventive maintenance state; a second acquisition module for acquiring state data of ship equipment; a frequency analysis module for performing a frequency analysis on the time spent on each state transition process according to the state data to obtain the cumulative distribution of the time spent on each state transition process; a rate determination module for determining the state transition rate of each state transition process according to the cumulative distribution of the time spent on each state transition process.

[0016] Optionally, the state transition process includes transitioning from a preventive maintenance state to a good state and from a preventive maintenance state to a serviceable state. The frequency analysis module is further used to obtain a set of preventive maintenance strategies, where the set of preventive maintenance strategies includes preventive minor repairs, preventive medium repairs, and preventive major repairs. Based on the state data, a frequency analysis is performed on the time spent on different preventive maintenance strategies to obtain a cumulative distribution of the time spent on each preventive maintenance strategy.

[0017] Optionally, the rate determination module is further used to determine the state transition rate corresponding to each preventive maintenance strategy based on the cumulative distribution of the time spent by each preventive maintenance strategy; and determine the state transition rate from the preventive maintenance state to the intact state and the state transition rate from the preventive maintenance state to the serviceable state based on the state transition rate corresponding to each preventive maintenance strategy and the nested relationship between the preventive maintenance strategies.

[0018] Optionally, in the rate determination module, the state transition rate from the preventive maintenance state to the intact state is expressed by the following formula:

[0019] The state transition rate from the preventive maintenance state to the serviceable state is expressed by the following formula:

[0020] in, is the state transition rate from the preventive maintenance state to the intact state, is the state transition rate from the preventive maintenance state to the serviceable state, The probability of performing preventive minor repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after a preventive minor repair. The probability of conducting preventive repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive repairs. The probability of performing preventive overhauls on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive overhaul. is the state transition rate corresponding to preventive minor repairs, is the state transition rate corresponding to the preventive repair, is the state transition rate corresponding to preventive overhaul, 、 and It is determined according to the nested relationship between the preventive maintenance strategies.

[0021] Optionally, in the rate determination module, the probability of the ship equipment undergoing preventive minor repairs is It is expressed by the following formula:

[0022] The probability of the ship equipment undergoing preventive maintenance It is expressed by the following formula:

[0023] The probability of the ship equipment undergoing preventive overhaul It is expressed by the following formula:

[0024] in, 、 The value of is related to the nested relationship between the preventive maintenance strategies, which includes: If a minor preventive repair is performed, a medium preventive repair must be performed. A preventive overhaul must be carried out after each preventive medium overhaul.

[0025] In a third aspect, a computer device is also provided, comprising: a memory and a processor, wherein the memory stores at least one computer program, and the at least one computer program is loaded and executed by the processor, thereby executing the method for determining the comprehensive rate of preventive maintenance of ship equipment described in the above embodiment.

[0026] In a fourth aspect, a computer-readable storage medium is also provided, in which at least one computer program is stored. The at least one computer program is loaded and executed by a processor, thereby executing the method for determining the comprehensive rate of preventive maintenance of ship equipment described in the above embodiment.

[0027] In a fifth aspect, a computer program product is provided, comprising a computer program / instruction, which implements the method described in the first aspect when executed by a processor.

[0028] The beneficial effects of the technical solutions provided by the embodiments of the present disclosure include at least: In the embodiment of the present disclosure, by performing frequency analysis on the time spent on each state transition process based on the state data, the cumulative distribution of the time spent on each state transition process can be accurately obtained, and based on the cumulative distribution, the state transition rate of each state transition process of the ship equipment can be accurately calculated. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0030] Figure 1 A flow chart of a method for determining a comprehensive rate of preventive maintenance of ship equipment provided by an exemplary embodiment of the present disclosure is shown; Figure 2 It is a status network diagram of ship equipment; Figure 3 is a schematic diagram of a frequency histogram; Figure 4 A flow chart of a method for determining a comprehensive rate of preventive maintenance of ship equipment provided by another exemplary embodiment of the present disclosure is shown; Figure 5 It is a schematic diagram of the nested relationship of preventive maintenance strategies; Figure 6 A schematic structural diagram of a device for determining a comprehensive rate of preventive maintenance of ship equipment provided by an exemplary embodiment of the present disclosure is shown; Figure 7 It is a structural diagram of a computer device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] Unless otherwise defined, the technical or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present disclosure belongs. The words “first”, “second”, “third” and similar terms used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as “one” or “a” do not indicate a quantity limitation, but rather indicate the presence of at least one. Words such as “include” or “comprising” and similar terms mean that the elements or objects appearing before “include” or “comprising” cover the elements or objects listed after “include” or “comprising” and their equivalents, and do not exclude other elements or objects.

[0032] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0033] Figure 1 A flow chart of a method for determining a comprehensive rate of preventive maintenance of ship equipment provided by an exemplary embodiment of the present disclosure is shown. The method can be executed by a computer device. Figure 1 , the method comprising: In step 101, the status network of ship equipment is obtained.

[0034] The state network includes multiple state transition processes of ship equipment. The state transition process includes transitioning from a first state to a second state. The first state and the second state are different states in the state network. The state network includes a preventive maintenance state.

[0035] Shipboard instrumentation refers to the equipment used to measure and control relevant parameters and observe and measure objects during ship operation. There are many types of equipment used on ships, with different functions and performance.

[0036] Ship equipment can generally be divided into the following four categories: (1) Thermometers. Thermometers are divided into two categories based on how they are used: the first category is contact thermometers, including expansion type, pressure type, thermal resistance, and thermocouple thermometers; the second category is non-contact thermometers, which are usually used to measure high-temperature objects above 1000°C that are moving, rotating, or react rapidly. The second category of thermometers includes optical pyrometers, photoelectric pyrometers, spectroscopic pyrometers, colorimetric pyrometers, infrared pyrometers, etc.

[0037] (2) Pressure gauges. They are divided into three categories based on the different pressure measurement principles: the first category is pressure gauges that use liquid column pressure measurement, including U-tube pressure gauges, single-tube pressure gauges, inclined tube pressure gauges, and piston pressure gauges. They are commonly used to measure the scavenging pressure of diesel engines and the wind pressure of boiler blowers. The second category is pressure gauges that use elastic deformation to measure pressure, including spring tube pressure gauges and electric contact pressure gauges. The third category is other types of pressure gauges, such as average pressure gauges and maximum pressure gauges.

[0038] (3) Tachometer. Commonly used tachometers include the following four categories: mechanical centrifugal tachometer, electrical tachometer (generator type, capacitor type and eddy current type), mechanical technical tachometer, and photoelectric counting tachometer.

[0039] (4) Density meter, flow meter, hygrometer, salinity meter, etc.

[0040] Ship equipment includes intact condition, serviceable condition, fault condition and preventive maintenance condition.

[0041] When the equipment is in good condition, the measurement error of the equipment is very small. In the embodiment of the present disclosure, it is assumed that the equipment in good condition is regarded as brand new equipment.

[0042] When in a usable state, there are certain errors in the equipment's measurement data, but it can still be used and the measurement data still has reference value.

[0043] In a faulty state, the equipment cannot be used and requires immediate corrective repair or direct replacement. Corrective repair or direct replacement can restore the equipment to its original condition (that is, to its perfect condition).

[0044] The preventive maintenance status can also be called the overhaul status. Preventive maintenance can repair the equipment to be as good as new (that is, to be in perfect condition) or it can repair the equipment to be as good as old (that is, to be in usable condition).

[0045] Figure 2 This is a state network diagram of ship equipment. Figure 2As shown, state 1 is a good state, state 2 is a usable state, state 3 is a fault state, state 4 is the first preventive maintenance state, and state 5 is the second preventive maintenance state. Figure 2 In the figure, the solid line represents the continuous state transition process, and the dotted line represents the discrete state transition process.

[0046] The first preventive maintenance state and the second preventive maintenance state are essentially the same, the difference is that the pre-state transition process between the first preventive maintenance state and the second preventive maintenance state is different. The state transition process involved in the first preventive maintenance state includes: the ship equipment starts timing from entering the intact state, and after a period of time , it is still in good condition, and then it is transferred from the good condition to the first preventive maintenance state. The state transfer process involved in the second preventive maintenance state includes: the ship equipment starts timing from entering the good condition, and at time Within a certain period of time, it degrades to a usable state, and after a period of time in a usable state , transfer from the serviceable state to the second preventive maintenance state. The interval for preventive maintenance, It is the time for the ship equipment to transfer from the serviceable state to the second preventive maintenance state.

[0047] Therefore, it can be seen Figure 2 States 4 and 5 are essentially the same, meaning the combined preventive maintenance rates for the ship equipment involved in States 4 and 5 are also the same. The combined preventive maintenance rates for ship equipment involved in States 4 and 5 include the rate of transition from preventive maintenance to intact state and the rate of transition from preventive maintenance to serviceable state.

[0048] comprehensive Figure 2 From the state network in , we can know that when considering the comprehensive rate of preventive maintenance of ship equipment, we actually need to calculate the following five state transition rates: the rate of transfer from intact state to serviceable state, the rate of transfer from serviceable state to faulty state, the rate of transfer from faulty state to intact state, the rate of transfer from preventive maintenance state to intact state, and the rate of transfer from preventive maintenance state to serviceable state.

[0049] In step 102, status data of ship equipment is obtained.

[0050] Ship equipment status data can be collected during the operation and maintenance of ship equipment. This data reflects the status of a particular piece of equipment. This data can be divided into two categories: the first is equipment performance data, including standard data and measurement data. The second is maintenance data collected during equipment maintenance.

[0051] Equipment performance data refers to the data displayed by the equipment during use. Standard data is the accurate data displayed by the equipment corresponding to the operating conditions. This data may be provided at the time the equipment leaves the factory or determined based on experience during actual use and maintenance. Measured data is the data displayed by the equipment under specific operating conditions during actual use. Equipment maintenance data (such as failure rate) directly reveals the failure patterns of the equipment.

[0052] If the collected status data belongs to the second type of data, the current status of the equipment can be directly obtained. If the collected status data belongs to the first type of data, the current status of the equipment can be determined based on the relative error of the equipment.

[0053] For example, the relative error of the equipment is expressed using formula (1).

[0054] (1) In formula (1), It is the relative error of the equipment. The measured value refers to the data obtained by measuring with the equipment under certain working conditions in actual use; the standard value is the data accurately displayed by the equipment under the same working conditions.

[0055] The relative error value of the equipment can, to a certain extent, reflect the reliability level of the equipment. The larger the relative error value, the less accurate the data measured by the equipment. When the relative error reaches a certain level, the displayed data of the equipment is no longer of reference value, the equipment cannot perform its measurement function, and it can be considered that the equipment has failed. Therefore, two error thresholds can be set, and the status of the equipment can be determined by the relationship between the relative error of the equipment and the error threshold. When the relative error of the equipment is less than the first error threshold, it means that the equipment is in good condition; when the relative error of the equipment is between the first error threshold and the second error threshold, it means that the equipment is in a usable condition; when the relative error of the equipment is greater than the second error threshold, it means that the equipment is in a faulty state. The values ​​of the first error threshold and the second error threshold are empirical values ​​and are not limited in this embodiment of the present disclosure.

[0056] In step 103, a frequency analysis is performed on the time taken for each state transition process based on the state data to obtain a cumulative distribution of the time taken for each state transition process.

[0057] The frequency analysis process involved in step 103 is described by taking the state transition process from the intact state to the usable state as an example. The method in step 103 can be applied to the subsequent frequency analysis processes.

[0058] Different state transition processes require the collection of different types of state data. For the two state transition processes—from intact to serviceable and from serviceable to faulty—only the installation and removal times of the ship equipment, as well as the equipment status at those times, can be collected. For the three state transition processes involving maintenance—from faulty to intact, from preventive maintenance to intact, and from preventive maintenance to serviceable—additional data must be collected.

[0059] For example, for the state transition process from a faulty state to an intact state, it is necessary to collect the disassembly time of the equipment that is in a faulty state when disassembled, and the installation time of the equipment after disassembly (for equipment that is in a faulty state when disassembled, corrective repairs or direct replacements will be performed after disassembly, and the equipment that is installed after disassembly must be in an intact state).

[0060] For the transition from preventive maintenance status to intact status and from preventive maintenance status to usable status, it is necessary to collect the start time of preventive maintenance, the completion time of preventive maintenance (the equipment after preventive maintenance will be reinstalled, and the completion time of this preventive maintenance is equivalent to the installation time of a certain equipment after it was disassembled for preventive maintenance) and the equipment status after the completion of preventive maintenance.

[0061] For the two state transition processes—from intact to serviceable and from serviceable to faulty—the state data collection assumes that the equipment's status is monitored during use and that it is disassembled and replaced due to failures or preventive maintenance. This means that both corrective and preventive maintenance require the equipment to be disassembled before repairs can be performed. Apart from this, no other repairs are performed on the equipment during use. Under this assumption, the process from installation to disassembly to confirm its status is considered a complete process, and the data corresponding to each process is extracted from the collected data.

[0062] When analyzing the cumulative distribution of the time it takes for equipment to transition from a good state to a usable state, the relative error value of each piece of equipment at the time of disassembly can be calculated. , and extract the installation time and removal time of each equipment, and calculate the duration between the installation time and removal time of each equipment In this way, each state data can form a number pair .

[0063] Among these pairs, The number pairs between the first error threshold and the second error threshold can be used to perform frequency analysis on the state transition process from the intact state to the usable state. The number of pairs between the first error threshold and the second error threshold has a common These pairs can be expressed as , according to this Number of pairs Frequency analysis can be performed. Define the time it takes for equipment to enter a usable state from a good state for the first time as a random variable, denoted as .

[0064] When conducting frequency analysis, first Number of pairs Create a frequency histogram, the frequency histogram can be initially seen Obey the cumulative distribution. Figure 3 is a schematic diagram of the frequency histogram, such as Figure 3 As shown, the vertical axis of the frequency histogram is frequency (frequency = frequency / ), the horizontal axis is the duration, where the duration represents the time it takes to move from a good state to a usable state. By connecting the frequency points corresponding to the midpoints of each interval in the frequency histogram, a curve can be obtained, which can preliminarily reflect the Obey the cumulative distribution.

[0065] In order to further calculate the The best cumulative distribution that follows can be The possible cumulative distributions are verified separately.

[0066] In the embodiments of the present disclosure, The possible cumulative distributions include exponential distribution, Weibull distribution, extreme value distribution, etc. Calculated based on frequency analysis The cumulative distribution of , the regression model of exponential distribution, Weibull distribution and extreme value distribution is used to The sample data is tested for distribution fit and compared. The greater the goodness of fit between the cumulative distributions, the better the fitting effect. The cumulative distribution with the largest goodness of fit is selected as The cumulative distribution of .

[0067] In some embodiments, software tools can also be used to perform curve fitting to determine The method of curve fitting using software tools is often used for curve fitting of unknown data with uncertain distribution types, but it is also applicable to data that can perfectly match known distributions. It can directly fit the given distribution function parameters and derive the state transition rate function that meets the modeling requirements.

[0068] In step 104, the state transition rate of each state transition process is determined according to the cumulative distribution of the time taken by each state transition process.

[0069] For the first type of state transition process, if the cumulative distribution function of the time taken for a state transition process is known, the probability density function corresponding to the time taken for the state transition process can be further calculated, and the state transition rate of the state transition process can be calculated based on the cumulative distribution function and the probability density function. The first type of state transition process does not include preventive maintenance. The first type of state transition process includes transitions from a good state to a usable state, from a usable state to a faulty state, and from a faulty state to a good state.

[0070] The state transition rate of any first-class state transition process can be expressed by formula (2).

[0071] (2) In formula (2), represents the state transition rate of a first-class state transition process, represents the probability density function of the first type of state transition process, Represents the cumulative distribution function of the first type of state transition process.

[0072] Take a first-class state transition process that obeys exponential distribution or Weibull distribution as an example to illustrate.

[0073] The probability density function of the exponential distribution is , the cumulative distribution function of the exponential distribution is .in is the average time.

[0074] If a first-class state transition process obeys an exponential distribution, then the probability density function and the cumulative distribution function of the exponential distribution are substituted into formula (2) to calculate the state transition rate of the first-class state transition process: .

[0075] The probability density function of the Weibull distribution is , the cumulative distribution function of the Weibull distribution is .That is the average time, is the shape parameter.

[0076] If a first-class state transition process obeys the Weibull distribution, then the probability density function of the exponential distribution and the cumulative distribution function of the exponential distribution are substituted into formula (2) to calculate the state transition rate of the first-class state transition process: .

[0077] The second type of state transition process includes transitioning from the preventive maintenance state to the intact state and from the preventive maintenance state to the serviceable state. For the second type of state transition process, since there are different strategies for preventive maintenance, that is, when a certain ship equipment enters the preventive maintenance state, it is not fixed to perform preventive maintenance, but a preventive maintenance strategy is randomly performed according to probability. Therefore, the state transition rate of this type of state transition process cannot be directly calculated using formula (2). Instead, it is necessary to first use formula (2) to calculate the rate of different preventive maintenance strategies, and then calculate the state transition rate of the second type of state transition process based on the rate of different preventive maintenance strategies and the probability of different preventive maintenance strategies.

[0078] In an embodiment of the present disclosure, by performing a frequency analysis on the time spent on each state transition process based on the state data, a cumulative distribution of the time spent on each state transition process is obtained. Based on the cumulative distribution, the state transition rate of each state transition process of the ship equipment can be accurately calculated.

[0079] The calculation of the state transition rate of the second type of state transition process is described below.

[0080] Figure 4 A flow chart of a method for determining a comprehensive rate of preventive maintenance of ship equipment provided by another exemplary embodiment of the present disclosure is shown. The method can be executed by a computer device. Figure 4 , the method comprising: In step 401, the status network of ship equipment is obtained.

[0081] The state network includes multiple state transition processes of ship equipment, and the state transition process includes transitioning from a first state to a second state. The first state and the second state are different states in the state network. In step 402, status data of ship equipment is obtained.

[0082] The relevant contents of step 401 to step 402 refer to the aforementioned step 101 to step 102, and detailed description is omitted here.

[0083] In step 403, a preventive maintenance strategy set is obtained.

[0084] The preventive maintenance strategy set includes preventive minor maintenance, preventive medium maintenance and preventive major maintenance.

[0085] After a preventive minor overhaul, there's a high probability the equipment will be restored to serviceable condition, with a low probability of returning to good condition. After a preventive medium overhaul, the equipment will return to either good condition or serviceable condition, respectively, with a certain probability. After a preventive major overhaul, there's a high probability the equipment will be restored to serviceable condition, with a low probability of returning to serviceable condition. Preventive maintenance can be performed in both good and serviceable conditions.

[0086] There is a nested relationship between preventive maintenance strategies. In the embodiment of the present disclosure, the nested relationship between preventive maintenance strategies includes: If a minor preventive repair is performed, a medium preventive repair must be performed. A preventive overhaul must be carried out after each preventive medium overhaul.

[0087] Figure 5 It is a schematic diagram of the nested relationship of preventive maintenance strategies. Figure 5 middle, and Taking 2 for both, it can be seen that for every two preventive minor repairs, a preventive medium repair is required, and for every two preventive medium repairs, a preventive major repair is required.

[0088] In step 404, frequency analysis is performed on the time spent on different preventive maintenance strategies based on the status data to obtain the cumulative distribution of the time spent on each preventive maintenance strategy.

[0089] When conducting frequency analysis on the time spent on different preventive maintenance strategies, taking preventive minor repairs as an example, the time difference between the start time and the completion time of preventive minor repairs for each equipment can be obtained. , the time difference is used to indicate the time taken for preventive minor repairs. Then, the time taken for preventive minor repairs is subjected to frequency analysis using the method of step 103, and finally the cumulative distribution of the time taken for preventive minor repairs is obtained.

[0090] Preventive maintenance and preventive overhaul can also be treated in the same way as preventive minor maintenance, so that the cumulative distribution of the time spent on each preventive maintenance strategy can be obtained.

[0091] In step 405, the state transition rate corresponding to each preventive maintenance strategy is determined according to the cumulative distribution of the time spent by each preventive maintenance strategy.

[0092] After obtaining the cumulative distribution of the time spent on each preventive maintenance strategy, the state transition rate corresponding to each preventive maintenance strategy can be obtained through the method in step 104.

[0093] Taking preventive minor repairs as an example, we first determine the probability density function corresponding to preventive minor repairs based on the cumulative distribution function that preventive minor repairs obey. Then, we substitute the cumulative distribution function and probability density function of preventive minor repairs into formula (2) to obtain the state transition rate of preventive minor repairs.

[0094] Preventive medium maintenance and preventive overhaul can also be processed in the same way as preventive minor maintenance, so that the state transition rate corresponding to each preventive maintenance strategy can be obtained.

[0095] In step 406, the state transition rate of the second type of state transition process is determined according to the state transition rate corresponding to each preventive maintenance strategy and the nested relationship between the preventive maintenance strategies.

[0096] The second type of state transition process includes the state transition rate from the preventive maintenance state to the intact state and the state transition from the preventive maintenance state to the serviceable state.

[0097] Optionally, the state transition rate from the preventive maintenance state to the intact state is expressed by formula (3).

[0098] (3) The state transition rate from the preventive maintenance state to the serviceable state is expressed by formula (4).

[0099] (4) In formula (3) and formula (4), is the state transition rate from the preventive maintenance state to the intact state, is the state transition rate from the preventive maintenance state to the serviceable state, The probability of performing preventive minor repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after a preventive minor repair. The probability of conducting preventive repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive repairs. The probability of performing preventive overhauls on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive overhaul. is the state transition rate corresponding to preventive minor repairs, is the state transition rate corresponding to the preventive repair, is the state transition rate corresponding to preventive overhaul, 、 and Determined based on the nested relationship between preventive maintenance strategies. 、 and is a known constant value, which can be taken from experience, and is usually .

[0100] Probability of ship equipment undergoing preventive minor repairs It is expressed as formula (5).

[0101] (5) Probability of ship equipment undergoing preventive maintenance It is expressed using formula (6).

[0102] (6) Probability of ship equipment undergoing preventive overhaul It is expressed as formula (7).

[0103] (7) In formulas (5) to (7), 、 The value of is related to the nested relationship between preventive maintenance strategies. The nested relationship between preventive maintenance strategies includes: If a minor preventive repair is performed, a medium preventive repair must be performed. For every preventive medium repair, a preventive overhaul must be performed. The meanings of the other parameters in formulas (5) to (7) are the same as those in formulas (3) and (4), and their detailed description is omitted here.

[0104] A state network equation can be constructed based on the state network, and the above-mentioned comprehensive rate can be applied to the state network equation to facilitate solving the state network equation.

[0105] set up For equipment The state at the moment, based on the state network, adopts the supplementary variable method to introduce the state residence time , then the state transition process of the equipment can be regarded as a generalized Markov process, and the state network equation can be expressed by formula (8).

[0106] (8) In formula (8), Indicates time, the stay time is The equipment is in the state The probability of is a positive integer, The value range of is 1 to 5. The definitions of states 1 to 5 refer to the aforementioned step 101, and the detailed description is omitted here. Indicates the rate of transition from a good state to a usable state, Indicates the rate of transition from a usable state to a faulty state, Indicates the rate of transition from a faulty state to a healthy state, Indicates the rate of transfer from preventive maintenance state to intact state, Indicates the rate of transfer from preventive maintenance state to serviceable state. The above five rates are all residence time These five rates can be calculated using the methods in steps 101 to 104 and steps 401 to 406.

[0107] The steady-state solution of the state network equation exists. When solving the probability of each state in the steady state, since the probability in the steady state is independent of the absolute time, the absolute time in the state network equation can be directly , then formula (8) can be simplified to the form of formula (9).

[0108] (9) In formula (9), Indicates the length of stay The equipment is in the state The probability of is a positive integer, The value range of is 1 to 5. The meanings of other parameters in formula (9) are the same as those in formula (8), and their detailed description is omitted here.

[0109] Step b, during the preventive maintenance interval, the time value Solve the state network equation under the condition of The probability that the corresponding ship equipment is in each state.

[0110] Time value is the first time set A time value.

[0111] After obtaining the state network equation (i.e., formula (9)), boundary conditions and initial conditions can be defined to solve the state network equation.

[0112] The boundary conditions can be expressed using formula (10), and the initial conditions can be expressed using formula (11).

[0113] (10) (11) In formula (10) and formula (11), Indicates length of stay When 0 is taken (that is, the initial situation), the equipment is in state The probability of The interval for preventive maintenance, is the time from the serviceable state of the ship equipment to the second preventive maintenance state. The meanings of other parameters in formula (10) are the same as those in formula (9), and their detailed description is omitted here.

[0114] Combining the boundary conditions, initial conditions and state network equations yields formula (12).

[0115] (12) The meanings of the parameters in formula (12) are the same as those in formula (9) and formula (10), and their detailed description is omitted here.

[0116] When the equipment state transfer network reaches a steady state, the state The steady-state probability can be expressed as: .

[0117] State 1 and State 2 are special. State 1 stays for a period of time. When the system is in state 1, it will definitely transfer to state 4 for preventive maintenance. , so Similarly, state 2 stays for a period of time When the time is up, it will definitely transfer to state 5 for preventive maintenance. So the stay time in state 2 is , so Moreover, the sum of the probabilities of all states in the equipment state network in the steady state is 1, that is, On this basis, we can solve formula (6) to obtain the value of the steady-state probability of the ship equipment being in each state in the state set. The values ​​of these steady-state probabilities are related to and The value of is related.

[0118] It should be noted that It refers to the interval period when the equipment is in a steady state and transfers from a serviceable state to a preventive maintenance state. It consists of two parts. First, the preventive maintenance timing starts from the time when the equipment enters a good state. During the preventive maintenance interval T, the equipment reaches a serviceable state but does not reach a fault state. At this time Second, the preventive maintenance timer starts from the moment the equipment enters the serviceable state. .

[0119] Combining the above two parts, It can be expressed by the following formula (13).

[0120] (13) In formula (13), represents the steady-state probability of the equipment being in state 1, represents the steady-state probability of the equipment being in state 2. The meanings of other parameters in formula (13) are the same as those in formula (9) and formula (10), and their detailed description is omitted here.

[0121] Combining formula (12) and formula (13), we can see that due to 、 、 、 、 are all known parameters, so the variables in the simplified state network equation (that is, formula (12)) are and ,and You can also use To express.

[0122] Based on this, when solving the state network equation, we can first set , and then give the initial value of the steady-state probability of the equipment in each state (that is, arrive ), substituting these initial values ​​into formula (13) to obtain The initial value of 、 Substitute the initial value of into formula (12) to solve the steady-state probability of each state in the first iteration. Then the steady-state probability of each state in the first iteration can be substituted into formula (13) to obtain the steady-state probability of each state in the second iteration. , and then , in the second iteration Substitute into formula (12) to solve the steady-state probability of each state in the second iteration. Multiple iterations can be performed in this way until the error between the steady-state probability of each state in the mth iteration and the steady-state probability of each state obtained in the m+1th iteration is less than the error threshold, indicating that the iteration can be stopped. At this time, the steady-state probability of each state obtained in the mth iteration or the m+1th iteration can be used as the final preventive maintenance interval. The steady-state probability of the ship equipment being in each state under the condition of .

[0123] For example, When it indicates that the iteration can be stopped, is the steady-state probability of the i-th state in the m-th iteration, is the steady-state probability of the i-th state in the m+1-th iteration, m is a positive integer, is the error threshold, exemplarily, .

[0124] The following are device embodiments of the present application. For details not described in detail in the device embodiments, reference may be made to the above method embodiments.

[0125] Figure 6 The schematic diagram of the structure of the device for determining the comprehensive rate of preventive maintenance of ship equipment provided by an exemplary embodiment of the present disclosure is shown. Figure 6 The ship equipment preventive maintenance comprehensive rate determination device 600 includes: a first acquisition module 601, a second acquisition module 602, a frequency analysis module 603 and a rate determination module 604.

[0126] The first acquisition module 601 is used to obtain the status network of ship equipment. The status network includes multiple status transition processes of the ship equipment. The status transition process includes transitioning from a first state to a second state. The first state and the second state are different states in the status network. The status network includes a preventive maintenance state.

[0127] The second acquisition module 602 is used to acquire status data of ship equipment.

[0128] The frequency analysis module 603 is used to perform frequency analysis on the time spent in each state transition process according to the state data, and obtain the cumulative distribution obeyed by the time spent in each state transition process.

[0129] The rate determination module 604 is configured to determine the state transition rate of each state transition process according to the cumulative distribution of the time taken by each state transition process.

[0130] Optionally, the state transition process includes transitioning from a preventive maintenance state to a good state and from a preventive maintenance state to a serviceable state. The frequency analysis module 603 is further configured to obtain a set of preventive maintenance strategies, which includes preventive minor maintenance, preventive medium maintenance, and preventive major maintenance. Based on the state data, a frequency analysis is performed on the time spent on different preventive maintenance strategies to obtain a cumulative distribution of the time spent on each preventive maintenance strategy.

[0131] Optionally, the rate determination module 604 is further configured to determine a state transition rate corresponding to each preventive maintenance strategy based on a cumulative distribution of the time spent on each preventive maintenance strategy; and to determine a state transition rate from a preventive maintenance state to a good state and a state transition rate from a preventive maintenance state to a serviceable state based on the state transition rate corresponding to each preventive maintenance strategy and the nested relationship between the preventive maintenance strategies.

[0132] Optionally, in the rate determination module 604, the state transition rate from the preventive maintenance state to the intact state is expressed by the following formula:

[0133] The state transition rate from the preventive maintenance state to the serviceable state is expressed by the following formula:

[0134] in, is the state transition rate from the preventive maintenance state to the intact state, is the state transition rate from the preventive maintenance state to the serviceable state, The probability of performing preventive minor repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after a preventive minor repair. The probability of conducting preventive repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive repairs. The probability of performing preventive overhauls on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive overhaul. is the state transition rate corresponding to preventive minor repairs, is the state transition rate corresponding to the preventive repair, is the state transition rate corresponding to preventive overhaul, 、 and Determined based on the nested relationship between preventive maintenance strategies.

[0135] Optionally, in the rate determination module 604, the probability of the vessel equipment undergoing preventive minor repairs is It is expressed by the following formula:

[0136] Probability of ship equipment undergoing preventive maintenance It is expressed by the following formula:

[0137] Probability of ship equipment undergoing preventive overhaul It is expressed by the following formula:

[0138] in, 、 The value of is related to the nested relationship between preventive maintenance strategies. The nested relationship between preventive maintenance strategies includes: If a minor preventive repair is performed, a medium preventive repair must be performed. A preventive overhaul must be carried out after each preventive medium overhaul.

[0139] It should be noted that the above-mentioned embodiment of the device for determining the comprehensive rate of preventive maintenance of ship equipment only uses the division of the above-mentioned functional modules as an example to illustrate the determination of the comprehensive rate of preventive maintenance of ship equipment. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the device for determining the comprehensive rate of preventive maintenance of ship equipment provided in the above-mentioned embodiment and the method for determining the comprehensive rate of preventive maintenance of ship equipment are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0140] The division of modules in the embodiments of the present disclosure is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of the present disclosure may be integrated into a single processor, exist physically as separate modules, or be integrated into a single module. The integrated modules may be implemented in either hardware or software functional modules.

[0141] If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present disclosure, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a terminal device (which can be a personal computer, mobile phone, or communication device, etc.) or a processor to execute all or part of the steps of the method of each embodiment of the present disclosure. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program code.

[0142] Figure 7 Schematic diagram of the structure of the computer device provided by the embodiment of the present disclosure. Figure 7 As shown, the computer device 700 includes a processor 701 and a memory 702 .

[0143] Processor 701 may include one or more processing cores, such as a quad-core processor or an octa-core processor. Processor 701 may be implemented in hardware using at least one of the following: a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), or a PLA (Programmable Logic Array). Processor 701 may also include a main processor and a coprocessor. The main processor is used to process data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 701 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing content displayed on the display screen. In some embodiments, processor 701 may also include an AI (Artificial Intelligence) processor, which is used to handle computational operations related to machine learning.

[0144] Memory 702 may include one or more computer-readable storage media, which may be non-transitory. Memory 702 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in memory 702 is used to store at least one instruction, which is executed by processor 701 to implement the method for determining the comprehensive rate of preventive maintenance of ship equipment provided in embodiments of the present disclosure.

[0145] Those skilled in the art will understand that Figure 7 The structure shown in the figure does not constitute a limitation on the computer device 700, and the computer device 700 may include more or fewer components than shown in the figure, or combine some components, or adopt a different component arrangement.

[0146] The embodiment of the present disclosure also provides a non-temporary computer-readable storage medium. When the instructions in the storage medium are executed by the processor of a computer device, the computer device is able to execute the method for determining the comprehensive rate of preventive maintenance of ship equipment provided in the embodiment of the present disclosure.

[0147] The embodiments of the present disclosure also provide a computer program product, including a computer program / instruction, which, when executed by a processor, implements the method for determining the comprehensive rate of preventive maintenance of ship equipment provided in the embodiments of the present disclosure.

[0148] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A method for determining the comprehensive rate of preventive maintenance of ship equipment, characterized in that: The method comprises: Acquire a state network of ship equipment, the state network including a plurality of state transition processes of the ship equipment, the state transition process including transitioning from a first state to a second state, the first state and the second state being different states in the state network, the state network including a preventive maintenance state; Obtain status data of ship equipment; Performing a frequency analysis on the time spent on each state transition process according to the state data to obtain a cumulative distribution of the time spent on each state transition process; The state transition rate of each state transition process is determined according to the cumulative distribution obeyed by the time spent by each state transition process.

2. The method according to claim 1, characterized in that The state transfer process includes the transfer from the preventive maintenance state to the intact state and the transfer from the preventive maintenance state to the serviceable state. The performing frequency analysis on the time spent on each state transition process according to the state data to obtain the cumulative distribution obeyed by the time spent on each state transition process includes: Obtaining a preventive maintenance strategy set, wherein the preventive maintenance strategy set includes preventive minor maintenance, preventive medium maintenance, and preventive major maintenance; According to the state data, frequency analysis is performed on the time spent on different preventive maintenance strategies to obtain the cumulative distribution of the time spent on each preventive maintenance strategy.

3. The method according to claim 2, characterized in that Determining the state transition rate of each state transition process according to the cumulative distribution of the time spent by each state transition process includes: Determining a state transition rate corresponding to each preventive maintenance strategy according to a cumulative distribution of the time spent by each preventive maintenance strategy; According to the state transition rate corresponding to each preventive maintenance strategy and the nested relationship between the preventive maintenance strategies, the state transition rate from the preventive maintenance state to the intact state and the state transition rate from the preventive maintenance state to the serviceable state are determined.

4. The method according to claim 3, characterized in that The state transition rate from the preventive maintenance state to the intact state is expressed by the following formula: The state transition rate from the preventive maintenance state to the serviceable state is expressed by the following formula: in, is the state transition rate from the preventive maintenance state to the intact state, is the state transition rate from the preventive maintenance state to the serviceable state, The probability of performing preventive minor repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after a preventive minor repair. The probability of conducting preventive repairs on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive repairs. The probability of performing preventive overhauls on ship equipment, The probability that the ship's equipment will be restored to a good condition after preventive overhaul. is the state transition rate corresponding to preventive minor repairs, is the state transition rate corresponding to the preventive repair, is the state transition rate corresponding to preventive overhaul, 、 and It is determined according to the nested relationship between the preventive maintenance strategies.

5. The method according to claim 4, characterized in that The probability of the ship's equipment undergoing preventive minor repairs It is expressed by the following formula: The probability of the ship equipment undergoing preventive maintenance It is expressed by the following formula: The probability of the ship equipment undergoing preventive overhaul It is expressed by the following formula: in, 、 The value of is related to the nested relationship between the preventive maintenance strategies, which includes: If a minor preventive repair is performed, a medium preventive repair must be performed. A preventive overhaul must be carried out after each preventive medium overhaul.

6. A device for determining the comprehensive rate of preventive maintenance of ship equipment, characterized in that: The device comprises: a first acquisition module, configured to acquire a state network of ship equipment, wherein the state network includes a plurality of state transition processes of the ship equipment, wherein the state transition process includes transitioning from a first state to a second state, wherein the first state and the second state are different states in the state network, and wherein the state network includes a preventive maintenance state; The second acquisition module is used to obtain status data of ship equipment; A frequency analysis module is used to perform a frequency analysis on the time spent on each state transition process according to the state data to obtain a cumulative distribution of the time spent on each state transition process; The rate determination module is used to determine the state transfer rate of each state transfer process according to the cumulative distribution obeyed by the time spent by each state transfer process.

7. The device for determining the comprehensive rate of preventive maintenance of ship equipment according to claim 6, characterized in that: The state transfer process includes the transfer from the preventive maintenance state to the intact state and the transfer from the preventive maintenance state to the serviceable state. The frequency analysis module is further used to obtain a preventive maintenance strategy set, wherein the preventive maintenance strategy set includes preventive minor repairs, preventive medium repairs, and preventive major repairs; According to the state data, frequency analysis is performed on the time spent on different preventive maintenance strategies to obtain the cumulative distribution of the time spent on each preventive maintenance strategy.

8. A computer device, characterized in that: The computer device includes: a memory and a processor, wherein at least one computer program is stored in the memory, and the at least one computer program is loaded and executed by the processor to implement the method according to any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores at least one computer program, and the at least one computer program is loaded and executed by a processor to implement the method according to any one of claims 1 to 5.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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