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International audience; Accelerated degradation test (ADT) is generally used to accelerate degradation processes in products to estimate their lifespan and to assess their reliability in a short period of time. How to perform the failure mechanism consistency test is crucial in the application of the ADT method. Existing failure mechanism consistency test methods assume that degradation rates among individual products are the same. However, these methods do not take degradation dispersions caused by manufacturing technologies into consideration. To address this issue, a failure mechanism consistency test method for ADT based on the activation energy invariant method and the likelihood ratio test is proposed. First, a degradation modeling method for ADT is introduced. Then, the logarithmic maximum likelihood function values of the degradation models are estimated based on the two-step maximum likelihood estimation (MLE) method. Finally, the decision rule is proposed based on the likelihood ratio test. The method mentioned above is, then, used on the real degradation data of carbon-film resistors and bullet O-rings, and its effectiveness is verified. Furthermore, based on the failure mechanism change point in RTV5370 siloxane rubbers, the simulated degradation data are degenerated to compare the proposed method with the method not considering individual differences in different ADT programs and degradation dispersions.

Additional file 2: Table S1. Primer sequences for splice variant expression.

Additional file 1. Supplementary figures.

Accelerated degradation test (ADT) is considered as a method for obtaining product degradation data in a short period of time, and the life and reliability of the product are inferred under the conditions of use.In order to ensure the effectiveness of ADT, guaranting that the failure mechanism of the product under each accelerated stress is consistent with the failure mechanism under normal stress is necessary. Therefore, it is necessary to carry out an accelerated degradation failure mechanism consistency discriminant test. At present, the determination of the test variables in the accelerated degradation failure mechanism consistency discriminant test is mainly based on experience, and lacks a set of experimental optimal methods with theoretical basis. In this paper, in order to solve the above problems, save sample capacity and reduce testing time, D-Optimality for step stress is applied to optimal design of accelerated degradation failure mechanism consistency discriminant test based on Wiener process.First, we apply Wiener process to describe an accelerated degradation failure mechanism consistency discriminant test. Then, we apply D-Optimality for step stress that by using the expenditure function and the decision variable function as restrictions, the sample capacity, the optimal total test time and the optimal time at each stress level are given. At last, a case study is used to illustrate the proposed method.

Accelerated degradation test (ADT) is an important mean to obtain products’ degradation data, perform life prediction and assess reliability. An effective ADT needs to ensure failure mechanism consistency of products between various accelerated stresses and normal stress. Thus, a new test method for failure mechanism consistency of accelerated degradation test based on wiener process is proposed in this paper. Frist, degradation modeling for products based on Wiener process is established, and the link between the drift parameter of the Wiener process and accelerated stresses is set up by using accelerated models, such as Arrhenius equation. The relationship among drift parameters under different accelerated stresses is deduced based on the hypothesis that failure mechanism of products under different stresses is consistent when corresponding failure activation energies are invariant. Then, test samples are constructed separately under different stresses and assumed to satisfy a normal distribution, and t statistic is used for these samples to test failure mechanisms consistency. Finally, the accelerated storage degradation data of a certain type of resistor are used as an example to calculate failure mechanism variation interval of this resistor, which verifies the effectiveness of the method proposed in this paper.

Substation equipment temperature is one of the important criteria to reflect its normal work in[1], this article through the new UHF-RFID sensor temperature measures substation equipment, the new passive wireless sensor through the work of two frequency bands to solve the energy supply. The results show that this method can accurately predict the temperature of the primary equipment of the substation, diagnose fault and monitor equipment in real time by using the neural network and the seven main factors that affect the temperature of the primary equipment of the substation.

Background Tumor invasion or adherence to the portal vein–superior mesenteric vein (PV/SMV) may be encountered during pancreatic surgery. In such cases, venous resection and reconstruction might be required for complete resection of the tumor. We report an innovative technique in which the graft for PV/SMV reconstruction was made with the falciform ligament. Methods Between May 2011 and July 2016, PV/SMV reconstruction with a falciform ligament graft was performed in 10 cases during pancreatectomy. Among these cases, including six cases with a patch graft and four cases with a conduit graft. Retrospective reviews of medical records and radiologic studies were performed. Results Ten patients with pancreatobiliary cancer underwent en bloc tumor resection with concurrent PV/SMV resection and reconstruction with a falciform ligament graft. There were six males and four females, and the mean age was 65.3 ± 9.4 (48-80) y. Using Doppler ultrasound examination, all 10 grafts were shown to be patent at postoperative 2 wk. However, occlusion was found in one case with conduit graft and stenosis in the other three cases with conduit graft using enhanced computed tomography at postoperative 2 mo. Complete patency was shown in three of six cases with patch graft and stenosis in the other three cases at 2 mo after the operation. Although occlusion or stenosis of the grafts was observed, no severe adverse events occurred, and normal liver function was discovered in all 10 cases at postoperative 2 mo. Conclusions Falciform ligament grafts might be considered for reconstruction of PV/SMV in the absence of appropriate vascular grafts.

Objective: To study the clinical features of nonalcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC). Methods: The clinical manifestations, imaging features, pathological subtypes and treatment outcome of two cases with NAFLD-associated HCC were analyzed. Results: In these two cases, both were young, obese male patients, with contrast enhanced CT scan of hemangioma-like features. They had undergone surgical resection and both were reported as well-differentiated HCC pathologically. They were followed-up respectively up to 46 and 36 months post-operatively with no evidence of recurrence or metastasis. Conclusions: NAFLD-associated HCC has different radiological presentations from typical HCC. Incidental finding of any liver occupying lesions in NAFLD patients should raise immediate clinical attention.

Reversible logic studies have promising potential on energy lossless circuit design, quantum computation, nanotechnology, etc. This paper proposes an analogic selection sorting algorithm essentially based on the transformation-based algorithm. It uses an unweighted, undirected graph for the representation of all transformable paths. During the synthesis process, a sequence of transformations are performed to enable all the output patterns to appear in the right place. The whole process can be implemented by a sequence of Toffoli gates. In addition, a simplification algorithm is put forward to further optimize the generated circuit. The experimental results show that this algorithm, compared with other exact methods, can achieve optimal or nearly optimal solutions with less computation time. Furthermore, it is more easily understood and implemented.