1294 results about "Failure probability" patented technology

A method of analyzing vibrations of a rolling element bearing installed in a rotating machine includes accessing vibration data corresponding to the bearing to be analyzed, determining a degraded condition factor BD for the bearing, selecting an expected designer-determined mean-time-to-failure MTTF of the bearing operating under a design load in the operating environment of the rotating machine, selecting a forecast time period, calculating a reduced mean-time-to-failure RMTTF of the bearing using the expected designer-determined mean-time-to-failure MTTF and the degraded condition factor BD, calculating a probability of failure of the bearing in the forecast time period using the reduced mean time to failure RMTTF, accessing cost data corresponding to a cost of failure of the bearing in the rotating machine, calculating a financial risk from the calculated probability of failure in the forecast time period and the cost data, and displaying the financial risk for the selected time period.

Systems and methods for improving scrubbing techniques are provided. In one aspect, the error correction code for a memory line is strengthened by reorganizing the memory line into distinct portions and providing an error code set that includes a distinct error code for each portion of the memory line. In another aspect of the invention, the scan rate is effectively increased by moving memory scrubbing functionality into the memory system and distributing it among a number of subcomponents that can operate scrubbing functions in parallel. The effective scan rate increase reduces the probability of failure for any given ECC strength.

Analyzing an event chronology record to permit identification of periods of a production sequence that correspond to a high probability of failure. Systems and methods include receiving an event chronology for a particular machine in the production sequence and for a particular time interval. A reliability analysis system accesses process flow information to determine whether a particular event in the event chronology is related to a subsequent adverse event within a predefined event window.

A system and method for continuous online safety and reliability monitoring is disclosed. The method includes the steps of obtaining operating information about at least one of a plurality of instrumented function components, which are part of an instrumented function, and determining a probability of failure on demand for the instrumented function based on the operating information. In variations, operating information includes status information, which may be received from and/or provided to an asset management application. In some variations, instantaneous probability of failure on demand, online mean time to failure (MTTF), and online safety integrity level (SIL) are also calculated for an instrumented function. In yet further variations, the system allows a user to predict probability of failure on demand values into the future based on hypothetical and/or future planned test times.

The invention provides a method for processing conflict of a random access process and a measurement clearance, and relates to a terminal and a base station. The terminal is allocated with the measurement clearance; and the method comprises that: when the time period of the random access process is overlapped with the measurement clearance and can influence random access success, the terminal cancels the measurement clearance; or the terminal keeps the measurement clearance in the time period which is overlapped with the measurement clearance in the random access process and cannot influence the random access. The solution that the random access process priority is higher than the measurement clearance priority in the method improves the reliability of the random access process, reduces the failure probability of the random access process, reduces the delay of the random access process and takes the effective utilization of the measurement clearance into consideration.

Equipment failures are diagnosed using an integrated approach of case-based reasoning (CBR) and statistical reliability analysis. The method outputs a single list of suggested failed components, ranked by an overall probability of failure, and their associated past solutions from the case base. The overall probability of failure is calculated using the combined logic of case based reasoning and statistical reliability analysis. The method is typically used in a real-time decision support system to aid equipment diagnosis by a maintenance technician working in the field.

A database has a plurality of entries and a plurality of attributes common to each entry, where each entry corresponds to an individual. A query is received from a querying entity query and is passed to the database, and an answer is received in response. An amount of noise is generated and added to the answer to result in an obscured answer, and the obscured answer is returned to the querying entity. The noise is normally distributed around zero with a particular variance. The variance R may be determined in accordance with R>8 T log²(T/δ)/ε², where T is the permitted number of queries T, δ is the utter failure probability, and ε is the largest admissible increase in confidence. Thus, a level of protection of privacy is provided to each individual represented within the database. Example noise generation techniques, systems, and methods may be used for privacy preservation in such areas as k means, principal component analysis, statistical query learning models, and perceptron algorithms.

The invention discloses a probability method of an electronic product service life model based on a Bayesian theory. The probability method comprises four steps of: step 1, determining a main failure mechanism and a physical model; step 2, determining the source and a characterization method of each dispersibility in the main failure mechanism; step 3, determining the service life distribution obeyed by the main failure mechanism; and step 4, updating the parameter distribution according to the Bayesian theory, and obtaining the numerical solution of a probability service life model by combining a failure physical model and utilizing a Monte Carlo sampling method. The method disclosed by the invention is used for calculating the failure probability of a highly-reliable and long-service-life electronic product based on a stress damage model; and by analyzing diepersibility and a description method of factors such as the attribute, the size and the stress of each material causing the electronic product failure and considering the dispersibility factors on the basis of the traditional failure physical model, the probability of the failure physical model is realized, and a new approach is provided for describing the failure more accurately and forecasting the product storage life.

The invention discloses a circuit cluster-based method for analyzing a grid cascading failure, belonging to the technical field of safety protection of a power system. The method comprises the following steps of: applying a Bayes network failure tree theory to cascading failure analysis based on a distribution failure probability model of a self-critical circuit cluster and establishing a probability analysis model for a grid cascading failure based on cascading failure probability analysis of the self-critical circuit cluster in combination with the probability characteristic of a cascading failure developing stage; and through simulating a cascading failure process, performing risk assessment on the cascading failure by using a system load loss index and analyzing weak links of a system. By adopting the method, foundations are provided for a prevention strategy for further research on the reduction of cascading failure risk.

A probability evaluation method of failure caused by typhoon to a power transmission line is suitable for evaluating failure probability after the power transmission line is affected by the typhoon. The method mainly comprises the steps of quantitative evaluation on the power transmission line affected by the typhoon as well as environmental factors and probability modeling of the line failure caused by the typhoon. In the quantitative evaluation, ways of the failure caused by the typhoon to the power transmission line and key factors including inner factors (design strength, state and the like of lines) and outer factors (typhoon, terrain, rainfall and other factors) are mainly evaluated; and in the probability modeling, a reasonable failure probability model is mainly established to calculate the line failure probability corresponding to the quantitative evaluation results of the key factors. The probability evaluation method has the beneficial effects that the evaluation on various loads and real-time anti-wind capability of complicated lines and towers is avoided, the effect of the inner factors and the outer factors and the characteristics of the various failure ways are simultaneously considered, a mechanism that the failure of the line is caused by the typhoon is satisfied, and the capacity of a power system in defending the typhoon disaster is improved in combination with a wide-area measurement, analysis, protection and control system.

The invention provides a side slope stable reliability sensitivity analysis method based on Monte Carlo simulation. The side slope stable reliability sensitivity analysis method based on the Monte Carlo simulation includes: step 1, constructing a joint probability density function of uncertain parameters; step 2, using a Monte Carlo simulation method to obtain a side slope failure probability, and obtaining a failure sample; step 3, designing various sensitivity analysis schemes, and respectively constructing joint probability density functions of uncertain parameters under all the sensitivity analysis schemes; step 4, obtaining side slope failure probabilities under all the sensitivity analysis schemes; step 5, obtaining a variation trend of the side slope failure probabilities along with statistical characteristics of the uncertain parameters according to the side slope failure probabilities under all the sensitivity analysis schemes. The side slope stable reliability sensitivity analysis method based on the Monte Carlo simulation is wide in application range, simple in computation process, high in computation efficiency, and capable of effectively revealing a response regularity between the reliability level of a side slope and the statistical characteristics of the uncertain parameters, and has certain guiding significance for side slope risk control, design optimization and the like.

A single-mode optical fiber, cable, cord, and a method for ensuring a service life of the fiber are provided. The fiber has a core and a cladding, the fiber having a cut-off wavelength that exhibits a single-mode transmission in a 1.31 μm wavelength band. A relative refractive index difference of the core with respect to the cladding is adjusted such that a bending loss, when a bend is applied in a radius smaller than a limit bending radius of the fiber, becomes greater than a detection limit value. The limit bending radius is calculated from a relationship between a bending radius applied to the optical fiber and a failure probability which occurs after a time period. The method includes measuring a loss and ensuring that a failure probability of the fiber during a service life falls within a failure probability used for setting the limit bending radius.

Automated control of a cooling system cooling at least one electronic component is provided. The control includes monitoring over a period of time variation of an operational variable of the cooling system or of the at least one electronic component, and based, at least in part, on variation of the operational variable over the period of time, automatically determining whether to adjust control of the cooling system to limit variation of the operational variable. In one implementation, depending on the variation of the operational variable, and whether control of the cooling system has been previously adjusted, the method may further include automatically determining a probability of fail or an expected residual life of the cooling system, and responsive to the predicted probability of fail exceeding a first acceptable threshold or the expected residual life being below a second acceptable threshold, automatically scheduling for a cooling system repair or replacement.

The invention discloses a phase-changing failure suppression method based on direct current prediction control, and the method comprises the following steps of inputting direct current Id_inv at an inversion side and alternative-current bus three-phase instantaneous voltage ua, ub and uc; adopting a phase-changing failure prediction control module to detect the operation state of a current alternative-direct-current system so as to judge whether the phase-changing failure of an inverter happens or not; adopting a phase-changing failure prediction control module to predict and output an inverter trigger retardation angle variation value delta ainv_PREV; detecting a judgment signal of the phase-changing failure prediction control module, predicting a direct current setting value if the phase-changing failure possibly occurs to obtain a prediction value Id_PREV, and otherwise enabling the direct current to be a normal setting value Id_NOR; and outputting the Id_PREV and the delta ainv_PREV to a rectifier and inverter control system to be used for suppressing the phase-changing failure. Due to the adoption of the phase-changing failure suppression method, the phase-changing failure probability of a direct-current power transmission system can be reduced.

A physical frame preamble symbol receiving and processing method comprises the steps as follows: processing a received digital signal to obtain a baseband signal; judging whether there is a preamble symbol expecting to receive in the baseband signal, wherein the preamble symbol expecting to receive is a time-domain structure with a time-domain OFDM symbol as the main body and with a cyclic prefix in the front part and a modulation signal in the back part; and determining the position of the preamble symbol in a physical frame and parsing out signaling information carried in the preamble signal if there is a preamble symbol expecting to receive in the baseband signal. According to the technical scheme, the problem that a preamble symbol may fail to be detected by a low-complexity receiving algorithm under a complex frequency-selective fading channel under the condition of the current DVB_T2 standard or other standards is solved.

The invention discloses a generating method of a preamble symbol in a physical frame, comprising the following steps: carrying out discrete Fourier inverse transform on a frequency-domain OFDM symbol of a predetermined length to obtain a time-domain OFDM symbol; intercepting a time-domain OFDM symbol of the cyclic prefix length from the time-domain OFDM symbol as a cyclic prefix; generating a modulation signal based on the intercepted time-domain OFDM symbol of the cyclic prefix length; and generating a preamble symbol based on the cyclic prefix, the time-domain OFDM symbol and the modulation signal. By adopting the technical scheme, the problem in the current DVB_T2 standard and other standards that a DVB_T2 time-domain structure has no cyclic prefix and is not applicable to coherent detection and detection of a preamble symbol by using a low-complexity receiving algorithm under a complex frequency-selective fading channel may fail is solved.

An initial reliability of a semiconductor device is predicted before the design layout of a semiconductor product. A method of predicting the reliability of a semiconductor device according to the present invention: calculates the defect density of a plurality of wiring patterns on a wafer; extracts the critical area of a series of library elements formed of wiring patterns based on the defect density to determine the critical area value of each library element; determines a failure probability by wiring pattern from the result of a reliability test of the wiring pattern to form a correlation model from an expected value in which a defect is generated and which is obtained from the defect density and the failure probability of each wiring pattern; calculates the failure probability of each library element from the critical area value and the function of the correlation model; designs a layout of a semiconductor product with two library elements or more out of a series of the library elements combined together and calculates the reliability of the designed semiconductor device in consideration of the failure probability of the library elements combined together.