A new sudden death chart for the Weibull distribution under complexity

This article presents a new control chart for monitoring reliability using sudden death testing under the neutrosophic statistics (NS). The average run lengths of the in-control and the out-of-control process have been determined for evaluating the quick detection ability for small and moderate shifts. For the industrial use, tables and figures have been presented for different parameters. The proposed control chart is efficient in comparison with the existing control chart under classical statistics and value addition in the toolkit of the quality control personnel.

Health Technology Assessment of a new water quality monitoring technology: Impact of automation, digitalization and remoteness in dialysis units

Background Water quality monitoring at the dialysis units (DU) is essential to ensure an appropriate dialysis fluid quality and guarantee an optimal and safe dialysis treatment to patients. This paper aims to evaluate the effectiveness, economic and organizational impact of automation, digitalization and remote water quality monitoring, through a New Water Technology (NWT) at a hospital DU to produce dialysis water, compared to a Conventional Water Technology (CWT). Methods A before-and-after study was carried out at the Hospital Clínic Barcelona. Data on CWT was collected during 1-year (control) and 7-month for the NWT (case). Data on water quality, resource use and unit cost were retrospective and prospectively collected. A comparative effectiveness analysis on the compliance rate of quality water parameters with the international guidelines between the NWT and the CWT was conducted. This was followed by a cost-minimization analysis and an organizational impact from the hospital perspective. An extensive deterministic sensitivity analysis was also performed. Results The NWT compared to the CWT showed no differences on effectiveness measured as the compliance rate on international requirements on water quality (100% vs. 100%), but the NWT yielded savings of 3,599 EUR/year compared to the CWT. The NWT offered more data accuracy (daily measures: 6 vs. 1 and missing data: 0 vs. 20 days/year), optimization of the DU employees’ workload (attendance to DU: 4 vs. 19 days/month) and workflow, through the remote and continuous monitoring, reliability of data and process regarding audits for quality control. Conclusions While the compliance of international recommendations on continuous monitoring was performed with the CWT, the NWT was efficient compared to the CWT, mainly due to the travel time needed by the technical operator to attend the DU. These results were scalable to other economic contexts. Nonetheless, they should be taken with caution either when the NWT equipment/maintenance cost are largely increased, or the workforce involvement is diminished.

Long-Term Monitoring Reliability and Life Prediction of Fiber Bragg Grating-Based Self-Sensing Steel Strands

To analyze the long-term monitoring reliability and life expectancy of FBG-based steel strands, accelerated corrosion and tensile tests were carried out and a life-prediction model was constructed. The validation test results indicated that the monitoring strain sensitivity of FBG-based steel strands decreases with an increase in solution concentration and time in a corrosive acidic environment. When the sensitivity dropped to about 80% of its initial value, the FBG sensor suddenly failed. The life-prediction model indicates that the predicted monitoring life of an FBG sensor is about 56 years in an unstressed condition but about 27 years under the stressful conditions that FBG-based steel strands are subjected to in their working environment. So, to improve their monitoring reliability and monitoring life, it is suggested that FBG-based steel strands might be prepared by “pre-loading.”

Geotechnical monitoring of mining facilities in the system for assessing and ensuring the quality of geomechanical solutions

Relevance of the research. Effective monitoring of mining facilities is an essential component of the quality assurance system for geomechanical solutions. Modern systems that regulate monitoring of mining facilities are characterized by good elaboration and efficiency, however, the systems do not provide for formalization of monitoring, which excludes the optimization of monitoring in money and kind Purpose of research. The main reason for this situation is the lack of methods to make a reasonable quantitative assessment of the quality of observations, the potential damage from the effects of deformations and to formalize criteria and models for monitoring optimization taking into account the quality of observations, significance and features of the objects. Research methods. Quality of observations - the initial objective assessment of the quality of monitoring as a whole is defined as the product of three probabilities of detecting predetermined threshold levels of the state of a mining facility: functions of accuracy, frequency of observations and the number of control points. Knowing the quality of observations allows us to move on to formalizing monitoring itself based on the relationship of monitoring reliability (probability of detecting a dangerous situation) with information costs, levels of geomechanical risk, and geomechanical significance (potential damage from the effects of deformations). The latter means that the damage assessment should reflect the negative consequences of mining and construction, including hazard levels for working personnel and the population in the area of the monitoring object. A quantitative pre-drilling estimate of the reliability or probability of detecting dangerous deformations is established in the final phase of monitoring the forecasting of specific conclusions based on observations made about the state of mining facilities and their future trends. Three classes of methods are involved in forecasting: extrapolation, modelling, and examination. In addition to the classical extrapolation techniques based on the theory of time series, new procedures have been developed: for groups of control stations, sequential forecasting under conditions of instability of forecast horizons, forecast horizon correction for planned lead periods, nonparametric forecasting with guarantee coefficients. The possibilities of physical modelling in the aspect of forecasting the consequences of mining reserves in the non-working side of an active quarry with a collapsing system are investigated. For mining structures with increased levels of responsibility (tailing dams, developed areas under development, etc.), the possibilities of combining numerical and simulation modelling with extrapolation forecasting are shown, starting from “preventive” monitoring with the transition to the project forecast in phases of latent and active deformations. The domestic expert system of the All-Russian Research Institute of Mining Geomechanics and Survey has been digitalized in combination with simulation modelling, which ensures the reliability of assessments of the status of horizontal and inclined workings and chambers. Results and their application. Methods for quantitative monitoring performance monitoring are implemented in 12 programs and 33 text files. Typical monitoring models are presented that demonstrate the effectiveness of the adopted approach. The correspondence and convergence of the forecasting results with the results of practical use are shown. Conclusions. Criteria and models for monitoring mining structures are formalized taking into account the quality of observations, the significance and characteristics of the observed objects. Formalization of monitoring with access to its optimization is an obligatory component of the system of assessments and ensuring the quality of geomechanical solutions and is of independent importance.

Lessons Learned and Recommendations from the Implementation of a Live Coding Method to Assess Acceptability of SQ-LNS Supplements in 7- to 24-Month Old Children

Objectives To assess the feasibility of using a live coding method developed in a laboratory to a naturalistic field setting in Mexico and report lessons learned and recommendations for future use. Methods Two coders previously trained to reliability for video-coding of child food acceptance were trained on video live coding (coding video recordings of feeding sessions without pausing or playback) and live coding (LC) in the field. The live coding method was previously piloted and adapted to the Mexican context and common infant feeding practices. From 62 caregivers with 7- to 24-mo children taking part in a randomized field trial, 20 participated in a video-recorded home feeding session. The first 10 offers of food were coded. Each coder individually live coded 10 sessions and video live coded the other 10. Interclass correlation coefficients (ICC) were calculated between coders and with the supervisor to determine reliability. Results Four main categories of adaptations were identified: 1) personnel requirements, 2) participant considerations and instructions, 3) elements of setting, and 4) materials. In the Mexican context (and similar settings) we recommend: limiting the number of personnel entering the home to avoid disrupting the child's eating; offering precise instructions to caregivers on the feeding process; limiting distractions from family members; using a fix and a mobile recording device. Successful implementation of child-feeding LC protocols in the field must balance the following considerations: feasibility in the specific field context, local feeding practices, study resources and timelines, and maintaining quality data collection. All adaptations must prioritize LC best practices, including monitoring reliability during the training and LC period, across coders and a supervisor. Reliability levels in the Mexico setting were good (ICC > .80). Conclusions LC was feasible and successfully implemented in the Mexican field context. Its piloting in the field setting provided essential information to carry out necessary adaptations to the method prior to implementation. Continued use of this method requires context-specific adaptations aligned with best practice recommendations. Funding Sources Global Alliance for Improved Nutrition (GAIN).