Total Number Of Defects Research Articles

FLAW DEFECTION ANALYSE OF THE SURFACE OF ACRYLIC BASE PLASTICS

This study examines the possibility of assessing the quality of removable orthopedic devices by measuring the smoothness of their surfaces and detecting microscopic defects. The methodology involves comparing standard samples of the base material with samples that have been intentionally defective, using defectoscopy techniques for analysis. Initially, twenty samples of basic acrylic plastic were selected: half of them were perfectly machined to dental standards and the other half were intentionally scratched with sandpaper. These samples were then examined by macrophotography and analyzed using Image J software for quantitative image measurement. This analysis provided numerical data on the polished surface's quality, focusing on metrics such as the total number of defects, and the average size and perimeter of these defects. Statistical evaluation through the JUSP program compared the two sets of samples, highlighting significant differences between them. From the most prominent data points provided by Image J, conclusions were made regarding the surface quality of the acrylic plastic and how it is affected by specific mechanical imperfections. This method of using optical flaw detection offers a new way to clinically evaluate the quality of detachable orthopedic devices (like base plastic) in terms of their susceptibility to bacterial buildup, which could lead to inflammation in the prosthetic bed's mucosal lining. The use of flaw detection analysis allows for a general assessment of the quality of the material surface polishing, detection of surface defects in its structure that may occur during the production stage or during operation, thereby preventing areas of biofilm accumulation. Light-optical flaw detection in the experiment proved its effectiveness and makes us pay attention to the prospects of its improvement and wider implementation in clinical practice.

Neural Network-Based Fixed-Time Tracking Control for Input-Quantized Nonlinear Systems With Actuator Faults.

This study reports a fixed-time tracking control problem for strict-feedback nonlinear systems with quantized inputs and actuator faults where the total number of faults is allowed to be infinite. By taking advantage of radial basis function neural networks (RBFNNs), unknown nonlinear function terms in the system dynamic model can be effectively approached. In addition, based on the sector property of quantization nonlinearities and the structure of the actuator fault model, novel adaptive estimations and innovative auxiliary design signals are constructed to compensate for the influence caused by actuator faults and quantized inputs properly in the fixed-time convergence settings. Then, rigorous theoretical analysis manifests that the proposed control scheme can make the output tracking error converge to a small neighborhood of the origin within a fixed time, and the upper bound of the setting time not only does not depend on initial states of the system but also can be preassigned by selecting parameters appropriately. Meanwhile, all the signals in the closed-loop system remain bounded. Finally, a numerical example and a practical example of a single-link manipulator are presented to demonstrate the effectiveness of the proposed control algorithm.

ЭКСПЕРТИЗА КАЧЕСТВА ОНКОЛОГИЧЕСКОЙ ПОМОЩИ КАК ИНСТРУМЕНТ ПРИНЯТИЯ УПРАВЛЕНЧЕСКИХ РЕШЕНИЙ

Significance. Objective data, including results of quality assessment and expertise carried out by health insurance organizations as part of monitoring over volumes, service periods, quality and conditions of medical care delivery within the compulsory health insurance system are needed to make management decisions on organizing appropriate quality care delivery at the regional and institutional levels. The subject of study: quality of medical care provided to patients with cancer. The purpose of the study: to evaluate results of medical and economic expertise and quality assessment of cancer care, carried out by health insurance organizations in the Arkhangelsk region in 2018 –first half of 2023 (25,012 expert opinions). Material and methods. The study used depersonalized results of medical-economic expertise and quality assessment of medical care (25,012 expert opinions). Methods: retrospective analysis, statistical (calculation of extensive and intensive coefficients and their comparison), analytical method. Results. In general, the frequency of cancer care defects during the period under study equaled to 29.1 per 100 assessed cases. The leading group of defects included a failure, untimely or improper implementation of diagnostic and (or) treatment activities necessary for the patient (49.3%). The study has identified significant differences in the frequency and structure of the identified defects of medical care under different conditions of its provision, in medical organizations of different levels and in different nosological groups. Conclusion. The study shows a decline in the total number of defects in cancer care delivery with the same frequency of medical-economic expertise and quality assessment in the Arkhangelsk region in 2018 - first half of 2023. To identify causes of the leading groups of defects in the provision of medical care according to code 3.2. (failure, untimely or improper implementation of diagnostic and (or) treatment activities necessary for the patient), it is necessary to conduct a sociological survey (questionnaire) of doctors involved in cancer care delivery. Scope of application: management decision-making aimed to improving access to and quality of cancer care at the regional and institutional levels.

Investing Data Flow Issue by using Rayleigh Model in Cloud Computing

Programming groups benefit significantly from programming error forecasting, which also advances current achievement. Programming imperfection expectation has been the subject of experimental studies on both inside- and outside-project deformity forecast. However, current analyses dont appear to be able to provide a method for estimating the number of flaws in a soon-to-be-released product. This paper describes such an approach and determines the relationship between each indicator variable and the total number of defects using indicator variables obtained from the deformity speed increase, namely the imperfection thickness, deformity speed, and imperfection presentation time. We describe how a coordinated AI strategy was used in light of relapse models created using these indicator criteria. 3 distinct datasets with 228 occurrences were taken from the Kaggle store and subjected to analysis. The modified R-square for the relapse model developed as a component of the usual deformity speed was 98.6%, with a p-value of 0.001 being achieved. With a connection value of 0.98, the average deformity speed is clearly correlated with the number of flaws. As a result, it is demonstrated how this process might provide a framework for programmer testing in order to increase the viability of programming advancement activities.

Comprehensive evaluation of software system reliability based on component-based generalized G-O models.

The component-based software system has a core that is based on architecture design. Predicting the reliability growth trends of a software system in the early stages of the development process is conducive to reducing waste and loss caused by blind development. Restricted by the lack of information and data in the design and integration phase, it is difficult to implement reliability prediction research at this stage. In this article, we focus on a software system in which the reliability of each component follows the G-O model. First, two system-level parameters, which are the total number of system faults and the detection rate of the system faults, are defined. Then, by studying the relationship between the total number of faults and the detection rate of faults between the components and the system, the defined system parameters are calculated from the known component parameters. On this basis, and by incorporating the system parameters, we construct a reliability growth model for the software system, called the component-based generalized G-O model (CB-GGOM). Besides, two approximate models of CB-GGOM are proposed to facilitate reliability evaluation of the software system in the early and stable stages of the integration test. An engineering explanation of the proposed models is also provided, and their effectiveness is verified through simulation and with an authentic example. Since the proposed models are formulated without any integration test data, they are beneficial for developers to optimize test strategies of the software system and implement defect prevention in advance.

Long-term management practices successfully reduce bird-related electrical faults in a transmission grid increasingly used by white storks for nesting

Bird nests on transmission lines can cause electrical faults which reduce service reliability. To address this problem, since the mid-90s, the Portuguese Transmission System Operator (TSO) has undertaken management actions to discourage white storks Ciconia ciconia from nesting in hazardous locations of the pylons. Here, we compiled and analyzed an 18-year series of data on electrical faults, TSO management actions to tackle these, and stork nests on transmission pylons in Portugal to: (a) determine the relative importance of bird-related faults over the total number of faults; (b) describe variations in bird-related faults across time (season of the year and time of the day); (c) describe spatial variations in bird-related faults and their association with the occurrence of white stork nests on pylons; and (d) analyze the trends, over the years, of the number of white stork nests on pylons, the TSO management actions and their effectiveness in reducing bird-related fault rates. Overall, birds accounted, on average, for 25.3% of the electrical faults in the transmission network, with the vast majority being attributed to white storks. The seasonal pattern of bird-related faults showed higher rates in April and in October–November. Faults occurred more often during the night period, when storks spend more time on the pylons. We found a positive spatial relationship between the electrical fault rate and the proportion of pylons with stork nests (and the correlated number of nests per 100 km of line). There was, however, considerable variation in the fault rates not explained by the stork nest variables, particularly during the non-breeding season. The TSO management actions (namely removal/translocation of nests in hazardous locations of the pylons, installation of anti-perching devices and provision of alternative nesting platforms) significantly reduced, as a whole, the annual number of bird-related faults between 2001 and 2018, despite the three-fold increase in the number of white stork nests on transmission pylons. A deeper understanding of how white storks use the transmission pylons outside the breeding season is needed, so that targeted management actions can be taken to reduce the remaining bird-related fault rates to residual levels.

Spatial Characterization of Internal Defects in Medium Carbon Steel via X‐Ray Computed Tomography

Herein, the 3D characterization of internal defects in medium carbon steel with different soft reduction (SR) parameters is investigated, as regards its spatial morphology and size distribution using X‐ray computed tomography. The size of defects and their shape complexity increase from the equiaxed toward the center of the ingot, and the total number of defects is larger at the equiaxed region, which exhibits the aggregation and growth of small spherical pores into the large defects from equiaxed toward the center region. The two types of shrinkage defects, including island and net shrinkage, are identified. With the minimum reduction amount of 2 and 4 mm, the number and size of defects along with the carbon macrosegregation in the equiaxed region and center of the ingot are less as compared to the high reduction amount of 6 mm and without SR technology. The size of gas pores with sphericity >0.6 is <70 um with different reduction amounts and exceeds up to 150 um without SR. Therefore, minimum reduction amounts can easily regulate the internal defects in medium carbon steel.

Enhanced growth model of software reliability with generalized inflection S-shaped testing-effort function

The software project manager must plan and conduct testing activities economically and efficiently. Due to the constraints, such as limited testing resources, delivery time, and cost, it isn’t easy to conclude. The software reliability growth models (SRGMs) based on testing-effort, help the project manager in the decision process. Therefore, we reckon the testing effort function (TEF) during model formulation. This paper introduces a new model for estimating the growth of software reliability. This model incorporates generalized inflection S-shaped (GISS) distribution for TEF. Here, the TEF is involved as a time-dependent failure rate function. Besides, the developed model is in perfect debugging environment. Here, we estimate the values of the unknown parameters by the least square estimation (LSE). All the performance measures are calculated using real software failure data-set and comparisons made between the proposed model and the existing models. It is noted that the performance of the proposed model prediction for the total number of faults is more trustworthy.

Comprehensive approach to determination of space proton-induced displacement defects in silica optical fiber

Silica-based optical fibers presents a variety of applications used in radiation environments such as space, fusion facilities, accelerators and nuclear power plants. The radiation-induced displacement damage in optical fibers resulting in point defects may lead to attenuation signals that is a major concern for these applications. The present study proposes a computational approach to the calculation of the proton-induced displacement damage in vitreous silica. Therefore, Geant4 as a Monte Carlo particle transport code has been used to obtain the knock-on atom distributions caused by the interaction of space trapped proton with vitreous silica during an ISS mission. Moreover, molecular dynamics simulations using ReaxFF potential have been performed to produce the initial vitreous silica structure to evaluate the displacement damage cascades by LAMMPS package. The results show that ReaxFF has an appropriate potential to produce and evaluate the vitreous silica structure that provides better agreement with experimental data at both short-range and medium-range order. Furthermore, ODC(Si3) and NBOHC(O1) are dominant defect species created in the vitreous silica after trapped proton irradiation, where the total number of defects have increased on average by 94 for each keV increasing in PKA energy approximately.

Modelling the primary damage in Fe and W: influence of the short-range interactions on the cascade properties: Part 2 – multivariate multiple linear regression analysis of displacement cascades

Neutrons and high energy ions create displacement cascades in materials, which have been simulated using Molecular Dynamics, for many decades now. The breakthrough of this work is to explore in a large statistics of more than 7000 cascades the relation between early cascade morphology and the final primary damage using a multivariate multiple regression analysis. For two energies in Fe and W, the total number of defects, the number of SIA and vacancy clusters and their full size distributions have been characterized using a multivariate multiple linear regression analysis based on 7 descriptors of the primary damage and 3 morphology descriptors. We find that the combination of the volume and the sphericity is significant. This analysis highlights several cascade properties, among them, that the large and spherical cascades create less defects and in particular, less mono defects than small and fragmented ones. 13 interatomic potentials differing either by their equilibrium part or the way they were hardened have been included in this study and the multivariate analysis shows that the choice of potential has a limited influence on the total number of defects but a large one on the number of mono vacancies. On average, soft potentials create cascades of larger volume, smaller sphericity and producing more defects than hard potentials. Finally, the formation of vacancy clusters is different in Fe than in W. In Fe, the fraction of vacancies in clusters is larger than that of SIAs and larger vacancy clusters are created than SIA clusters. In W, it is the opposite. The reasons are the differences of stopping power and threshold displacement energies, which result in different spatial distributions of open volumes that form during the expansion stage of the cascade.

Proposed Improvement Product of Cake Pan Using The Six Sigma Method Approach (Case Study of PT. X)

PT. X is a manufacturing company that produces several cookware including Cake Pan. The total number of defects in Cake Pan for 3 months increased by a percentage of 0.384% of the total production of Cake Pan. The purpose of this study using the Six Sigma method is to identify and analyze proposals that can be given to control product quality in order to reduce defective products through the Six Sigma approach. This study found that the capability and sigma value of company performance in improving product quality amounted to 930.68 DPMO with a sigma value of 4.6. Based on the cause and effect diagram FMEA known causes of product defects are color defects, spiral defects, dent defects and hollow defects. Based on the results of the calculation of the RPN to determine the most critical and urgent focus priorities to be addressed, namely the quality of raw materials is not good to be the highest RPN value of 288 with a high severity level of 8. The proposals that can be given are in the form of worker SOPs and checking tables in the form of a system 5s. This research is expected to be useful for companies in providing input as well as an overview in the form of information to PT. X in giving more attention to product quality with several supporting factors that affect the quality of the product.

Automatic Extraction of Material Defect Size by Infrared Image Sequence

A typical pulsed thermography procedure results in a sequence of infrared images that reflects the evolution of temperature over time. Many features of defects, such as shape, position, and size, are derived from single image by image processing. Hence, determining the key frame from the sequence is an important problem to be solved first. A maximum standard deviation of the sensitive region method was proposed, which can identify a reasonable image frame automatically from an infrared image sequence; then, a stratagem of image composition was applied for enhancing the detection of deep defects in the key frame. Blob analysis had been adopted to acquire general information of defects such as their distributions and total number of defects. A region of interest of the defect was automatically located by its key frame combined with blob analysis. The defect information was obtained through image segmentation techniques. To obtain a robustness of results, a method of two steps of detection was proposed. The specimen of polyvinyl chloride with two artificial defects at different depths as an example was used to demonstrate how to operate the proposed method for an accurate result. At last, the proposed method was successfully adopted to examine the damage of carbon fiber-reinforced polymer. A comparative study between the proposed method and several state-of-the-art ones shows that the former is accurate and reliable and may provide a more useful and reliable tool for quality assurance in the industrial and manufacturing sectors.

Towards Quantitative Interpretation of Fourier-Transform Photocurrent Spectroscopy on Thin-Film Solar Cells

The method of detecting deep defects in photovoltaic materials by Fourier-Transform Photocurrent Spectroscopy has gone through continuous development during the last two decades. Still, giving quantitative predictions of photovoltaic device performance is a challenging task. As new materials appear, a prediction of potentially achievable open-circuit voltage with respect to bandgap is highly desirable. From thermodynamics, a prediction can be made based on the radiative limit, neglecting non-radiative recombination and carrier transport effects. Beyond this, more accurate analysis has to be done. First, the absolute defect density has to be calculated, taking into account optical effects, such as absorption enhancement, due to scattering. Secondly, the electrical effect of thickness variation has to be addressed. We analyzed a series of state-of-the-art hydrogenated amorphous silicon solar cells of different thicknesses at different states of light soaking degradation. Based on a combination of empirical results with optical, electrical and thermodynamic simulations, we provide a predictive model of the open-circuit voltage of a device with a given defect density and absorber thickness. We observed that, rather than the defect density or thickness alone, it is their product or the total number of defects, that matters. Alternatively, including defect absorption into the thermodynamic radiative limit gives close upper bounds to the open-circuit voltage with the advantage of a much easier evaluation.

Effort based release time of software for detection and correction processes using MAUT

The amalgamation of technologies in the information technology sector resulted in unprecedented growth in software reliability modelling in the past four decades. Over the period much attention has been given on developing a fault detection model and then considering fault correction as debugging processes as a complex process in which a detected fault may not immediately be corrected because of manipulation delays and some uncertainties. To overcome these issues academician and industrialists both are working hand in hand to find out the optimal software launch time by minimizing overall testing cost. Through this work, we have developed a unified framework for developing testing effort-based software reliability growth models to optimize the launch time of the software by minimizing the total cost incurred during the software lifecycle and considering fault detection and correction separately. Further, we have used multi-attribute utility theory by considering four attributes viz. cost, the ratio of detected and corrected faults, the ratio of the corrected and total number of faults, total effort utilized to establish the optimum software launch time. The recommended model is authenticated on a real-life software failure data set.

Adaptive neural fault-tolerant control for uncertain MIMO nonlinear systems with actuator faults and coupled interconnections

Handling both intermittent actuator faults and coupled interconnections in uncertain multiple-input–multiple-output nonlinear system is still a challenge in the control community. In this paper, to address this issue, an adaptive neural fault-tolerant control scheme is developed. Firstly, neural networks with random hidden nodes are used to approximate unknown functions, and an inequality is introduced to construct controllers such that the singularity problem of the controllers can be circumvented. Secondly, a projection algorithm is adopted to update online the estimated parameters in the controllers such that the boundedness of estimated parameters is ensured. In particular, the boundedness of estimate of unknown fault parameters with intermittent jumps can be definitely guaranteed. Due to the effects of intermittency jumps of unknown parameters on the system stability during operation, a modified Lyapunov function is developed to prove the system stability. It is proved that the system stability only depends on the jumping amplitude of Lyapunov function and the minimum fault time interval and is not affected by the total number of faults. Thirdly, a root mean square type of bound for the tracking error is established by using iterative calculation to illustrate that the system transient performance in the sense of the tracking error is adjustable by proper choice of design parameters. Finally, simulation studies are carried out to verify the effectiveness of the theoretical results.

Insights on patterns of developmental disturbances from the analysis of linear enamel hypoplasia in a Neolithic sample from Liguria (northwestern Italy)

ObjectiveTo assess developmental disturbances through the analysis of linear enamel hypoplasia (LEH) frequency and to infer environmental stress and life history within Neolithic communities from Liguria (Italy). Materials43 unworn/minimally worn permanent anterior teeth of 13 individuals recovered from nearby caves and dated to c. 4800−4400 cal. BCE. MethodsLEH defects were identified with high-resolution macrophotos of dental replicas, age at LEH was calculated via perikymata counts. LEH defects matched between two or more teeth were considered as systemic disturbances. LEH frequency by age classes was analyzed via GLZ and Friedman ANOVA. ResultsNumber of matched defects per individual range between 2–12. The mean LEH per individual was highest in the 2.5–2.99 age category, with a significant increase relative to earlier growth stages, followed by a decline. ConclusionLEH may reflect life-history in the local ecology of Neolithic Liguria, where several individuals with osteoarticular tuberculosis have been recorded. Disease burden may have triggered developmental disturbances around the time of weaning. Age at first defect was negatively correlated with age at death and positively with the total number of defects, suggesting that early stress may have affected survivorship. SignificanceThe study contributes to the reconstruction of ecological pressures among Neolithic people of Liguria, and informs on environmental challenges during the Neolithic adaptive expansion. LimitationsThe visual examination of macrophotos is prone to observer error; mid-crown tends to display more visible LEH due to tooth architecture. Suggestions for further researchApply different quantitative methods to examine severity and duration of disturbances.

Operation results of reversible converters of AC electric locomotives VL80<sup>R</sup> on the Krasnoyarskaya Railway

The article presents information about faults of reversible converters (RC) of AC electric locomotives of the VL80R series, fixed at the maintenance points of locomotives and locomotive depots of the Krasnoyarskaya Railway for the period 2014 – 2018. Authors provide data on the number of semi-conductor switches, their main parameters and technical characteristics for two types of converters — RC-2200 and RC-4000 operating on VL80<sup>R</sup> electric locomotives. Their influence on the RC construction scheme is shown. Revealed the causes of failures of the RC in the operation of electric locomotives. The role of maintenance of RC in electric locomotive and its monitoring system in ensuring reliable operation is shown as well as the statistical data on the quantitative and qualitative assessment of the types of failures of the RC. The article also shows statistics of changes in the number of converters of each type during the operation of electric locomotives. Information is given on the number of all faulty RCs on VL80R electric locomotives and an analysis of faulty RC-2200 and RC-4000s for a specified time period. The data is presented on the number of RC-2200 and RC-4000 failures per million km of the VL80<sup>R</sup> electric locomotive in terms of one section. Authors carried out analysis of statistics of this type of failure of the RC with reach-through breakdown of the shoulder. Information is given on the number of RCs with the reach-through breakdown of RC shoulders per million km of VL80R electric locomotives. It was concluded that for the period from 2014 to 2018, the number of failing RCs due to dangerous shoulder punctures decreased significantly, which led to a significant reduction in the number of failures of electric locomotives due to this failure. So, for RC-4000 this decrease occurred 5.75 times, and for RC-2200 2.4 times. In addition, the reason for a more significant reduction in the number of failures of electric locomotives with RC-4000 due to its faulty, is that RC-4000 is more modern and contains much fewer semi-conductor switches and additional elements. This increases the reliability of the RC. Thus, the replacement of obsolete RC-2200 with modern RC-4000 provided a reduction in the total number of faults of all RC in 2.3 times; decrease in the number of cases of RC failures per million km of a locomotive in 4 times.

Progress in Single Crystal Growth of Wide Bandgap Semiconductor SiC

The research and commercialization of SiC based power device have been burgeoning over the last decade worldwide, which is bringing about an increasing demand on lost-cost and low-defect SiC wafers. To meet this challenge, we have been continuously making efforts on improving the crystal growth and wafer processing techniques. Now, the mass-production of high quality 4-inch, 6-inch n-type and semi-insulating SiC wafers has been realized. Statistically, the micropipe density is lower than 0.5 cm-2. The resistivity of the wafers is lower than 0.02 Ω·cm and up to 108 Ω·cm for n-type and semi-insulating SiC single crystals, respectively. A state of the art processing technique has been developed to control wafer deformation and thickness within the desired values for subsequent epitaxy. The total defect number of the epitaxial layers grown on the "epi-ready" 4-inch SiC wafer is 63, and the usable area is 97.6%, indicating the high quality of our SiC substrates.

A fuzzy rule-based generation algorithm in interval type-2 fuzzy logic system for fault prediction in the early phase of software development

ABSTRACTReliability, a measure of software, deals in total number of faults count up to a certain period of time. The present study aims at estimating the total number of software faults during the early phase of software life cycle. Such estimation helps in producing more reliable software as there may be a scope to take necessary corrective actions for improving the reliability within optimum time and cost by the software developers. The proposed interval type-2 fuzzy logic-based model considers reliability-relevant software metric and earlier project data as model inputs. Type-2 fuzzy sets have been used to reduce uncertainties in the vague linguistic values of the software metrics. A rule formation algorithm has been developed to overcome inconsistency in the consequent parts of large number of rules. Twenty-six software project data help to validate the model, and a comparison has been provided to analyse the proposed model’s performance.

English

The permanence of harvested fruits in the plantation can cause irreversible damage to Conilon coffee quality, possibly increasing the overall number of defects, causing losses to crop yield and changing the organoleptic properties of the product. The objective of this study was to quantify the changes caused by permanence time of the Conilon coffee in the plantation after harvest over the mass and classification of the product. The experiment followed a completely random design, with 8 treatments and 4 repetitions, using standardized bags of mature fruits of Coffea canephora Pierre ex Froehner that were kept in the plantation field for periods of 0, 1, 2, 3, 4, 6, 8 or 10 days after manual harvest of the grains. After these periods, the coffee was dried, processed and weighted to quantify losses. The samples from each parcel were used to classify the resulting coffee regarding grain size in standardized classification sieves (sieves 12, 11 and 10 for round grains; sieves 17, 15 and 13 for flat grains), grain defects (brocaded, sour, black, defective percentage and total number of defects) and yield losses (dried coffee weight and processing ratio). The results showed that keeping the harvested fruits in the plantation causes losses over mass and over the overall product classification, affecting grain size and increasing the number and type of defects. This reinforces the recommendation to transport the harvested coffee for drying as soon as possible after harvesting.   Key words: Coffea canephora, harvest, grain defects, quality, physical classification.