—Multiteam systems (MTSs) have been increasingly adopted as an organizational form to manage large-scale projects. However, new product development (NPD) in the MTSs structure entails challenges with respect to achie...
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The damage effect assessment of anti-ship missiles combines system science and weapon science,which can provide reference for the assessment of battlefield damage *** order to solve the difficulty of heterogeneous dat...
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The damage effect assessment of anti-ship missiles combines system science and weapon science,which can provide reference for the assessment of battlefield damage *** order to solve the difficulty of heterogeneous data aggregation and the difficulty in constructing the mapping between factors and damage effect,this paper analyzes the specific damage process of the anti-ship missile to the ship,and proposes a synthetic Evidential Reasoning(ER)–Adaptive Neural Fuzzy Inference System(ANFIS)to assess the damage *** solve the problem of fuzziness and uncertainty of criteria in the assessment process,the belief structure model is used to transform qualitative and quantitative information into a unified mathematical structure,and ER algorithm is used to fuse the information of lower-level *** order to solve the problem of fuzziness and uncertainty of the information contained in the first-level variables,and the strong non-linear characteristics of the mapping between first-level variables and damage effect,the ANFIS with selfadaptation and self-learning is *** map between the three first-level variables and damage effect is established,and the interaction process of the various factors in the damage effect assessment are *** analysis shows that assessment model has good *** result analysis and comparative analysis show that the process proposed in this paper can effectively assess the damage effect of anti-ship missiles,and all criteria data are objective and comparable.
The optimization of condition-based maintenance (CBM) poses challenges due to the rapid advancement of monitoring technologies. Traditional CBM research has mainly relied on theory-driven approaches, which lead to the...
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The optimization of condition-based maintenance (CBM) poses challenges due to the rapid advancement of monitoring technologies. Traditional CBM research has mainly relied on theory-driven approaches, which lead to the development of several effective maintenance models characterized by their wide applicability and attractiveness. However, when the system reliability model becomes complex, such methods may run into intractable cost models. The Markov decision process (MDP), a classic framework for sequential decision making, has drawn increasing attention for optimization of CBM optimization due to its appealing tractability and pragmatic applicability across different problems. This paper presents a review of research that optimizes CBM policies using MDP, with a focus on mathematical modeling and optimization methods to enable action. We have organized the review around several key components that are subject to similar mathematical modeling constraints, including system complexity, the availability of system conditions, and diverse criteria of decision-makers. An increase in interest has led to the optimization of CBM for systems possessing increasing numbers of components and sensors. Then, the review focuses on joint optimization problems with CBM. Finally, as an important extension to traditional MDPs, reinforcement learning (RL) based methods are also reviewed as ways to optimize CBM policies. This paper provides significant background research for researchers and practitioners working in reliability and maintenance management, and gives discussions on possible future research directions.
Health systems are complex and health reform is uncertain. With an aging global population, chronic health conditions are increasing and have become a priority for policymakers. Hearing loss is the third most common c...
Health systems are complex and health reform is uncertain. With an aging global population, chronic health conditions are increasing and have become a priority for policymakers. Hearing loss is the third most common chronic condition among older adults and if left untreated, is associated with poor health and social outcomes. In the US, accessibility and affordability have been significant barriers to hearing aid utilization. Through new reform, over-the-counter (OTC) hearing aids are now available. This study demonstrates how publicly available health data was used to establish a methodology to define, characterize, and analyze the target population of this reform. In this retrospective cross-sectional cohort analysis, data from the National Health Interview Survey (NHIS) was utilized, with a sample that included respondents from the 2021 NHIS Sample Adult Interview. Three hearing aid groups (Active, Potential, General) were defined using questions from the NHIS annual core questionnaire and a baseline population health framework was developed. Binary logistic regression confirmed that the framework sufficiently described two group comparisons (Active-Potential, Active General) and also identified the key determinants of hearing aid utilization. Classification and regression tree (CART) classification amply predicted active hearing aid users and verified the key determinants as important predictors. These findings aligned nicely with literature published before OTC hearing aids were made available, confirming the NHIS to be consistent and representative. Our methodology can be repeated to examine the impact of OTC hearing aids in the post-implementation period and similar approaches should be taken to examine other emerging health reforms.
Ill-conditioned problems are ubiquitous in large-scale machine learning: as a data set grows to include more and more features correlated with the labels, the condition number increases. Yet traditional stochastic gra...
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Ill-conditioned problems are ubiquitous in large-scale machine learning: as a data set grows to include more and more features correlated with the labels, the condition number increases. Yet traditional stochastic gradient methods converge slowly on these ill-conditioned problems, even with careful hyperparameter tuning. This paper introduces PROMISE (Preconditioned Stochastic Optimization Methods by Incorporating Scalable Curvature Estimates), a suite of sketching-based preconditioned stochastic gradient algorithms that deliver fast convergence on ill-conditioned large-scale convex optimization problems arising in machine learning. PROMISE includes preconditioned versions of SVRG, SAGA, and Katyusha; each algorithm comes with a strong theoretical analysis and effective default hyperparameter values. Empirically, we verify the superiority of the proposed algorithms by showing that, using default hyperparameter values, they outperform or match popular tuned stochastic gradient optimizers on a test bed of 51 ridge and logistic regression problems assembled from benchmark machine learning repositories. On the theoretical side, this paper introduces the notion of quadratic regularity in order to establish linear convergence of all proposed methods even when the preconditioner is updated infrequently. The speed of linear convergence is determined by the quadratic regularity ratio, which often provides a tighter bound on the convergence rate compared to the condition number, both in theory and in practice, and explains the fast global linear convergence of the proposed methods.
This research studies the problems of stochastic dynamic scheduling in production systems with batch processes and process queue time (PQT) constraints. The production systems consist of upstream batch processing mach...
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The COVID-19 pandemic has put a spotlight on the global supply chain for medical equipment and medicines, highlighting vulnerabilities and disruptions in the healthcare *** paper aims to contribute to the ongoing rese...
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As a result of the increased number of COVID-19 cases,Ensemble Machine Learning(EML)would be an effective tool for combatting this pandemic *** ensemble of classifiers can improve the performance of single machine lea...
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As a result of the increased number of COVID-19 cases,Ensemble Machine Learning(EML)would be an effective tool for combatting this pandemic *** ensemble of classifiers can improve the performance of single machine learning(ML)classifiers,especially stacking-based ensemble *** utilizes heterogeneous-base learners trained in parallel and combines their predictions using a meta-model to determine the final prediction ***,building an ensemble often causes the model performance to decrease due to the increasing number of learners that are not being properly ***,the goal of this paper is to develop and evaluate a generic,data-independent predictive method using stacked-based ensemble learning(GA-Stacking)optimized by aGenetic Algorithm(GA)for outbreak prediction and health decision aided ***-Stacking utilizes five well-known classifiers,including Decision Tree(DT),Random Forest(RF),RIGID regression,Least Absolute Shrinkage and Selection Operator(LASSO),and eXtreme Gradient Boosting(XGBoost),at its first *** also introduces GA to identify comparisons to forecast the number,combination,and trust of these base classifiers based on theMean Squared Error(MSE)as a fitness *** the second level of the stacked ensemblemodel,a Linear Regression(LR)classifier is used to produce the final *** performance of the model was evaluated using a publicly available dataset from the Center for systems Science and engineering,Johns Hopkins University,which consisted of 10,722 data *** experimental results indicated that the GA-Stacking model achieved outstanding performance with an overall accuracy of 99.99%for the three selected ***,the proposed model achieved good performance when compared with existing baggingbased *** proposed model can be used to predict the pandemic outbreak correctly and may be applied as a generic data-independent model 3946 CMC,2023,vol.74,no.2 to pre
This study focuses on optimizing production parameters within a multi-stage sequential manufacturing system for the rayon fiber coagulating bath recycle process. It employs experimental design and mathematical program...
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Crisis management is preparing for and managing possible crises that may impact organizations and individuals at different levels. It involves effective communication, quick decision-making, and strategic planning to ...
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