411 results about "Failure risk" patented technology

A quantitative risk assessment system (QRAS) builds a risk model of a system for which risk of failure is being assessed, then analyzes the risk of the system corresponding to the risk model. The QRAS performs sensitivity analysis of the risk model by altering fundamental components and quantifications built into the risk model, then re-analyzes the risk of the system using the modifications. More particularly, the risk model is built by building a hierarchy, creating a mission timeline, quantifying failure modes, and building/editing event sequence diagrams. Multiplicities, dependencies, and redundancies of the system are included in the risk model. For analysis runs, a fixed baseline is first constructed and stored. This baseline contains the lowest level scenarios, preserved in event tree structure. The analysis runs, at any level of the hierarchy and below, access this baseline for risk quantitative computation as well as ranking of particular risks. A standalone Tool Box capability exists, allowing the user to store application programs within QRAS.

The invention discloses a mixed MMC-based mixed direct current power transmission system, comprising a rectifying converter station and an inversion converter station, wherein the inversion converter station adopts a mixed MMC. The direct current power transmission system has the active and reactive decoupling control capacity, can transmit power to a reactive network without the phase change failure risk and has direct current fault self-cleaning capacity; under the condition that a feeding end alternating current system has a fault; the mixed MMC has the capacity of outputting a negative level by using a full-bridge submodule, the direct current voltage output by the system can be reduced under the premise of ensuring the controllability and stability of the system, the direct current voltage can be matched with the direct current voltage of a rectifying station, and the direct current power is maintained to be continuously transmitted; due to the optimization on the number of two types of submodules in the mixed MMC, the use number of power electronic components is greatly reduced and the investment cost is reduced under the condition that the mixed modularized multi-level converter meets the stable and transient operation demands of the direct current system.

Careful repositioning of MOSFET gate contacts and increasing of their number makes MOSFET gate contacts more durable and reliable without requiring changes in either the leadframe design or the assembly process. Extension of the under-bump metal laterally from the gate contact with the gate pad metallization out to two or more gate pads not overlying the gate pad metallization minimizes the risk of delamination of the metallization due to thermal and mechanical stresses in assembly and operation. Use of more than one gate pad further reduces such failure risks. Positioning the gate pads sufficiently close to the original gate contact permits use of the same leadframe design and assembly process as would be used for a single gate pad placed directly over the gate contact. The result is a reliable, durable MOSFET gate contact compatible with current assembly methods.

Riser stress-engineering-assessment equipment to verify the integrity and the in-deployment-integrity of a riser string by knowing the status, details and location of each riser joint and by monitoring the deployment parameters. When the failure risk exceeds an acceptable level, the equipment activates a local and/or a remote alarm using voice, sound and lights. The system comprises a computer with communication means, a material properties and geometry detection system, a data acquisition system acquiring deployment and other parameters, a database comprising of riser historical data and captured expert knowledge, a failure-criteria calculation to calculate maximum-stresses under different loads and the combined effects of the different loads to determine if the riser string is still fit-for-deployment.

A technique is provided for managing bundles of constructs that may individually fail. Each bundle has a repetitively updated resource amount for counterbalancing a transfer of a failure risk pertaining to the respective bundle. Construct data is stored and a value of the resource amount is calculated for an individual time instance based on the construct data. It is determined whether a construct of a first bundle has failed. If not, a value of a resource amount for the first bundle is calculated, but if a construct has failed, a second bundle is generated that includes all constructs of the first bundle except for the construct having failed, and a value of a resource amount for the second bundle is calculated. The technique is particularly suitable for managing futures contracts that are based on a basket of credit default swaps as underlyings.

The invention discloses a novel electric propulsion system. The system comprises an internal combustion engine, an electric generator, an electric distribution system, a propulsion motor and a propeller, wherein the electric generator is in cable connection with the propulsion motor through the electric distribution system; the propulsion motor is connected with the propeller through a clutch and a speed reducer; both the electric generator and the propulsion motor are synchronous motors; and the propeller is an adjustable pitch propeller. The novel electric propulsion system effectively solves the problems of high investment cost, electric loss, severe harmonic pollution, difficult maintenance and high failure risk due to the adoption of a variable frequency technique by the electric propulsion system in the prior art and also solves the problems of high voltage drop in a system power grid and big torque born by a starting transient mechanical shaft due to the high starting transient current in the electric propulsion system in the prior art. The novel electric propulsion system has little investment, convenient installation and maintenance, a low running cost, high system reliability, low failure risk in a use process and a remarkable economic benefit.

A method for operating a system comprising multiple resources. The method comprises identifying for each resource a set of one or more failure risks for that resource. For each identified failure risk, a likelihood of failure is combined with an expected resolution time to provide a risk weight for the identified failure risk. For each resource, the risk weights for each failure risk are accumulated to provide an accumulated risk weight for the resource. A resource manager provisions workload across the multiple resources based on the accumulated risk weights for each resource.

The invention provides a method and system for assessing a risk of a multi-feed-in AC/DC system commutation failure. The method includes calculating an AC/DC voltage coupling effect factor and a critical AC/DC voltage coupling effect factor; and comparing the AC/DC voltage coupling effect factor and the critical AC/DC voltage coupling effect factor, and judging whether a risk of a commutation failure exists in a DC inverter side current conversion bus according to a comparison result. Compared with the prior art, the method and system for assessing the risk of a multi-feed-in AC/DC system commutation failure judge whether the risk of a commutation failure exists in the DC inverter side current conversion bus after a fault occurs in an AC bus of a receiving end system according to the comparison result of the AC/DC voltage coupling effect factor and the critical AC/DC voltage coupling effect factor, do not need to perform whole-network fault monitoring on an electric power system, greatly reduce the work amount of calculation and can rapidly assess whether a commutation failure risk exists in the DC inverter side current conversion bus.

Systems and methods for objective Deployment Failure risk assessments are provided, which may include fault trees. Systems and methods for the analysis of fault trees are provided as well. The risk assessments system may involve the development of a fault tree, assigning initial values and weights to the events within that fault tree, and the subsequent revision of those values and weights in an iterative fashion, including comparison to historical data. The systems for analysis may involve the assignment of well-ordered values to some events in a fault tree, and then the combination those values through the application of specialized, defined gates. The system may further involve the revision of specific gates by comparison to historical or empirical data.

Increasing the number of MOSFET gate bump contacts makes MOSFET gate contacts more durable and reliable. Extension of the under-bump metal laterally from the gate contact with the gate pad metallization out to two or more gate pads overlying the source pad metallization reduces the risk of delamination of the metallization due to thermal and mechanical stresses in assembly and operation. Use of more than one gate pad further reduces such failure risks. The result is a reliable, durable MOSFET gate contact.

The invention belongs to the field of relaying protection and risk analysis of power systems, and discloses a multi-mode hidden-failure risk analysis method of a relaying protection system. The method comprises the steps of building a multi-mode hidden-failure model of the relaying protection system; according to the multi-mode hidden-failure model, performing risk analysis on power grid N-k failures caused by relaying protection hidden failures, and obtaining risk index values of hidden failures of the relaying protection system. According to the method, simplified modeling analysis is performed on the hidden failures of the protection system; the multi-mode hidden-failure model is built by analyzing the characteristics of protection hidden failures with various typical modes; a power N-k grid failure analysis method is provided by aiming at the risk analysis problem of the hidden failures. An N-k failure probability solving method based on an improved functional group decomposition method and an event tree analysis method is adopted during the analysis, and corresponding cascading failure risk indexes are set up; the calculation accuracy of the power grid N-k failure probability is improved, and risk assessment and analysis can be performed on the hidden failures of the relaying protection system.

The invention relates to a system and method for estimating the failure risk of a household appliance. A household appliance failure pre-diagnosis system server is compared with a preset failure risk estimating model through self information uploaded by the household appliance and household environment information detected by a household environment detection system, whether the household appliance has the failure risk is judged, and if yes, the information and failure causes of the household appliance with the failure risk are sent to a user and an after-sales service department. On one hand, the user can timely discover the failure risk of the household appliance and deal with the failure risk timely in order to reduce repairing cost and shorten repairing time, and meanwhile, energy consumption caused by the failure risk in the rime range can be lowered. On the other hand, the after-sales service department can timely discover problems and provide after-sales service for the user timely in order to improve the degree of satisfaction of the user.

There is disclosed a method for assessing risk associated with drilling a section of a wellbore in a formation using a drilling system, comprising: providing a probabilistic model for the risk of the drilling system triggering a failure mode during drilling; and assessing the risk of the drilling system triggering one of said failure modes during drilling of the section based on said model. A further such method comprises: defining the critical control parameters for the drilling system; and identifying one or more failure modes of the drilling system associated with each critical control parameter which may arise during drilling the section of the formation.

The invention discloses a complex supply network robust performance analyzing method based on a topological structure. The method comprises the following steps: firstly providing a complex supply network topological structure model, and then applying the established model to perform the static robust performance analysis and dynamic robust performance analysis of a complex supply network, wherein the complex supply network topological structure model comprises mechanisms of increase, local selection and preferential connection; during the static robust performance analysis, structure robust performance of the supply network is analyzed by virtue of simulating and depicting different damages of the supply network by virtue of a computer; during the dynamic robust performance analysis, the dynamic robust performance of the network is analyzed by virtue of introducing external perturbation and a dynamic perturbation propagate algorithm. By means of modeling and simulation, the robust performance of the complex supply network suffering from different damages and perturbation can be effectively analyzed, and a solution conception is provided for a supply chain practitioner to reduce the supply failure risk.

Riser stress-engineering-assessment equipment to verify the integrity and the in-deployment-integrity of a riser string by knowing the status, details and location of each riser joint and by monitoring the deployment parameters. When the failure risk exceeds an acceptable level, the equipment activates a local and/or a remote alarm using voice, sound and lights. The system comprises a computer with communication means, a material properties and geometry detection system, a data acquisition system acquiring deployment and other parameters, a database comprising of riser historical data and captured expert knowledge, a failure-criteria calculation to calculate maximum-stresses under different loads and the combined effects of the different loads to determine if the riser string is still fit-for-deployment.

Various embodiments of the invention provide for stiction testing in MEMS devices, such as accelerometers. In certain embodiments, testing is accomplished by a high voltage smart circuit that enables an analog front-end circuit to accurately read the position of a movable proof-mass relative to a biased electrode in order to allow the detection of both contact and release conditions. Testing allows to detect actual or potential stiction failures and to reject defective parts in a Final Test stage of a manufacturing process where no other contributors to stiction issue can occur, thereby, minimizing stiction failure risks and extending the reliability of MEMS devices.

The invention discloses an aircraft structure checking task planning method based on risk and cost analysis. The checking mode comprises traditional structure non-destructive detection and structure health monitoring. The method comprises the steps that based on the principle of probability damage tolerance analysis, the calculation model of single flight failure probability of an aircraft structure element is established; based on the model, a cumulative risk calculation model of a fleet in a certain period of time is established; in the existing aircraft structure plan maintenance mode, the maintenance cost calculation model of the aircraft structure element in the service life cycle is established, wherein the calculation model comprises structure checking cost, repair cost and false alarm cost; the single flight failure risk and fleet cumulative risk are used as the risk assessment indicators of a structure maintenance policy; under the premise that a safety risk requirement is satisfied, the optimal structure checking policy can be determined according to the analysis of the structure whole service life cycle maintenance cost. The optimal structure checking interval and repair threshold can be determined based on the tradeoff between the structure failure risk and the service life cycle maintenance cost.