Influence Factors Of Reliability Research Articles

Effect of Liver Segments and Hepatic Fibrosis Grade on Repeatability, Reliability, and Diagnostic Efficiency of Intravoxel Incoherent Motion

Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) is considered a potential marker of hepatic fibrosis (HF). To explore the influencing factors of repeatability and reliability in IVIM-DWI parameters of ROI-based liver segments in participants with HF and healthy volunteers (HV) and to assess the diagnostic efficiency of these parameters in HF. Participants with early HF (EHF, n=59) or advanced HF (AHF, n=38) and HV (n=48) were recruited. Two examiners measured IVIM data using mono-, bi-exponential and stretched exponential models. The results and influencing factors of repeatability and reliability of IVIM-DWI, and the diagnostic efficiency were analyzed. The repeatability of D* (CV: 26.62-41.47%) and DDC (CV: 18.01-34.40%) was poor, the repeatability of ADC (CV: 4.95-9.76%), D (CV: 7.09-15.52%), f (CV: 9.35-17.15%), and α (CV: 7.48-13.81%) was better; ordered logistic regression showed statistically significant results of IVIM-derived parameters; the reliability showed no obvious trend, and ordered logistic regression showed statistically significant results of IVIMderived parameters, groups, and partial hepatic segments (all p<0.001). IVIM-derived parameters with relatively good repeatability (CV<20%) and reliability (ICC>0.4) were used to establish regression models for differential diagnosis. The AUC of regression models was 0.744-0.783 (EHF vs. AHF), but no statistically significant parameters were found in the HV vs EHF comparison. IVIM-derived parameters were the most important factors affecting the repeatability and reliability, while staging of HF and hepatic segments may be the influencing factors of reliability. IVIM-derived parameters showed medium diagnostic efficiency in distinguishing between EHF and AHF.

Reliability Analysis of Heavy-Duty Truck Diesel Engine Based on After-Sales Maintenance Data

Understanding the weak points and reliability influencing factors of products is the great significance for manufacturers to improve their design and make reasonable after-sales plans. Failure data are the basis for reliability analysis. Due to the long service life and high cost of engines, it is expensive and time-consuming to obtain failure data through reliability tests. After-sales maintenance data are an important reliability data, which intuitively reflects the field reliability performance of the product. In this paper, based on the after-sales maintenance data of heavy-duty truck diesel engines, the main failure points of diesel engines are identified, and the difference in service life of diesel engines under different service backgrounds is analyzed. In addition, gray relational analysis (GRA) is used to determine the main factors affecting the field reliability of diesel engines. The influence trend of usage rate on engine field reliability is analyzed. The results show that the fuel supply system has the highest proportion of failures in all subsystems. The failures of diesel engines mainly come from electronic devices and parts working in high-pressure environments. The service background has a significant impact on the life of the engine.

Petri Net-Based Reliability Assessment and Migration Optimization Strategy of SFC

With the development of information technology, the network consists of various proprietary hardware devices, and the use of these devices brings problems. To solve problems, network function virtualization is proposed, which decouples the software and hardware in the network, and deploys the existing network function devices to a common physical platform. However, network virtualization needs will inevitably face reliability problems during resource virtualization and service function chain deployment. This article proposes a service function chain reliability evaluation method and reliability optimization algorithm. The composition relationship and reliability influencing factors of service function chain were analyzed, including resource preemption, common cause failure, fault recovery and redundant backup. The service function chain was modeled as a Petri net model, and reliability evaluation results related to execution time were obtained. Based on the reliability assessment results, a VNF migration strategy is designed, with reliability as the optimization goal while considering costs. Simulation results show that, compared with the reliability optimization strategy based on backup, our algorithm costs less and reduces the impact of resource preemption on service reliability.

Reliability analysis of a floating offshore wind turbine using Bayesian Networks

A Bayesian Network is adopted to model and analyze the reliability of a floating offshore wind turbine. Reliability characteristics such as failure probability, failure rate, and mean time to failure of the floating offshore wind turbine are determined according to the Bayesian Network predictive analysis. In addition, critical systems, components, and reliability influencing factors of the floating offshore wind turbine are identified by the Bayesian Network diagnostic analysis. Moreover, the relationships between failure probabilities of critical reliability affecting factors and that of floating offshore wind turbine are obtained. The computed results in this paper are more conformity with statistical data for that the error of predicted failure rate of this study is 4.5%, which can be compared with that of 13% concluded by fault tree analysis.

A dynamic delay-based reliability evaluation model for communication networks

The traditional network reliability research generally focuses on the topological connectivity among given nodes based on graph theory. Without considering the relationship between network failures and network performance degradation, traditional network reliability analysis cannot reflect actual network ability reaching up to a certain accomplishment level over a utilization interval. As for the performability analysis of network with specific requirement of transmission time, this paper proposes a dynamic delay-based network reliability evaluation method, which considers network’s ability that transmission delay can be controlled under expected upper limit level in the course of network normal operating period, and puts forward a three-layer network reliability analysis architecture. By integrating a network component reliability model, a network topology model and a network performance model, the dynamic delay-based network reliability model is established, and the network reliability influence factors are integrated into network reliability evaluation. A simple example shows that for a given network, network reliability is different from specified performance requirement. Furthermore, network failures will result in network performance degradation in network long-term operation. It is also proven that network reliability relates not only to network topological connectivity but also to network application environment and specified performance requirement. The key contribution of this paper is to guide network engineers to design a high performance network by optimizing the network parameters according to the delay-based network reliability evaluation method proposed in this paper.

Prediction of water resource carrying capacity by the analytic hierarchy process-fuzzy discrimination method in a mining area

The problem of water damage caused by coal mining has been a widespread concern in all sectors of society. Research into carrying ability relations of coal mining and water resources in mining areas is the foundation to solve this problem. It is also important to evaluate the sustainable development of mining areas as well as explore aquifer-protective mining. Based on the analysis of the characteristics and connotations of mining area water resource carrying capacity (MAWRCC), the fuzzy synthetic discriminant method is used as the evaluation method, and water resource carrying capacity (WRCC) as the evaluation standard. The evaluation system of MAWRCC under a mining action is constructed, and the main influencing factors and subordinate functions of MAWRCC are analyzed. Also, the membership degree of the influence factor is calculated. Methods for the rationality and influence factors of reliability are proven in the Shendong and Yili mining areas. They predicted the state of WRCC of the Yili mine for the next three years, under the conditions of carrying out or not carrying out aquifer-protective mining. According to the calculation results, the parameters of coal mining are the initiating factor caused by MAWRCC. Aquifer-protective mining is an effective measure to control the WRCC. The research results have important reference value and academic significance for the evaluation of MAWRCC.

Optimisation of thermo-fatigue reliability of solder joints in surface mount resistor assembly using Taguchi method

The effect of geometric and ambient parameters on static structural integrity of solder joints in surface mount resistor assembled on printed circuit board (PCB) is investigated to improve the thermo-fatigue reliability of the joints and components. The optimisation of resistor thickness (RT) and components standoff height (CSH) in a range of operating homologous temperature (TH) is poised to produce optimal assembly which could accumulate least strain energy density (ωacc) in resistor joints and consequently possesses longer cycles to failure (Nf). Taguchi design of experiment (DOE), L9(33), is used to generate nine designs and finite element modelling (FEM) is employed to simulate the responses of the assemblies to reliability influencing factors (RIFs). The Garofalo–Arrhenius constitutive creep relation is utilised to model high-temperature response of the soldered joints while the concept of signal to noise ratio and statistics are used to determine the optimal design. The results show that settings of lowest RT, highest CSH and TH of 0.86 produce optimal assembly which demonstrates potential of reducing ωacc and increasing Nf of the best design of DOE by 46.9% and 88.3%, respectively. More results show that the nature of finite element model and difference in magnitude of thermal expansion coefficient (CTE) of two bodies bonded together and which experience the same temperature change determine the degree of damage on the interface with the former being more determining.The authors propose the model DM/N≡DN/M=K1×K23{1≤DM/N≡DN/M⟨∞1≤K1×K2⟨∞(where: M/N, K1, K2 are isotropic materials, CTE and geometric ratio, respectively) as a quick tool to rank and compare boundary damage in a multi-isotropic-material joining.

Reliability Test and Analysis of Electrical Automation Control Equipment

For a long time, reliability plays an extremely important role in electrical automation control equipment. To improve electrical automation control equipment’s reliability, the job should be promoted to a strategic height so as to assume and effectively control the factors affecting the reliability of the equipment, thus ensure the accuracy of reliability test. This paper, based on this, first is to implement the reliability influence factors analysis, and then introduces the main testing methods. By contrast, it finally comes to the conclusion that this article can provide certain reference for the research of related topics.

In Service Beam Bridge Reliability Assessment

In order to evaluate the reliability of existing bridges ,based on maximum value of the load and model of probability calculation of resistance attenuation, according to the data of the bridge which actually collected, and by using the ADINA finite element software to build the finite element model of considering the damage detection of beam bridge. The component and system failure criteria are determined on the basis of the bridge load-bearing characteristics.The Time-dependent reliability of the system by using the probability calculation model for assessing the maximum value of the load and resistance attenuation can be obtained. The result shows Changes in the process of reliability prediction of bridge , the correctness of reliability calculation model be verified; the correctness of the ADINA model be validated; Also confirmed the feasibility of prediction model; to obtain the main influencing factors of reliability of existing bridges.

Research on the Embedded Software Reliability Evaluation Model Based on Influence Factors

This paper firstly analyzes the reliability Influence factors of the embedded software, then puts forward an embedded software reliability evaluation model based on BP neural network, finally the preliminary application and verification of the model is given.

The Dynamic Reliability Analysis of Cryogenic Valve Based on Man-Machine-Environment System Theory

For comprehensively and quantify analyzing the resource of cryogenic valve fault, improving the operating reliability of cryogenic valve, by means of the dynamic character analysis in the operation reliability of cryogenic valve, dynamic reliability influence factors of cryogenic valve are analyzed by the introduction of on man-machine-environment system theory, and a model of dynamic reliability influence of cryogenic valve is established by the quantify analyzing of man-machine-environment influence factors to evaluate the reliability of cryogenic valve and to construct operation improving measures. Finally, this method was demonstrated and validated by a sample. It has shown the proposed method can improve the benefit of dynamic reliability researching of cryogenic valve, and provide a support for adapting to complex and dynamic operating environment of cryogenic valve.

Research on Quantitative Method about Driver Reliability

The influence factors of reliability for drivers in different running stage are analyzed in the paper, firstly, based on Behavior-causing Theory. Then a new quantification method on transience reliability for drivers is advanced by a new definition “reliability degree”, whose error rate is calculated by the response time of drivers, and the influence factors how to influent the transience reliability degree is also researched. The whole reliability of drivers could be described by the new method. The results show the new method could not only statistics the reliability but also describe the relationship between reliability and time.