Selecting statistical model and optimum maintenance policy: a case study of hydraulic pump.
Ruhi, S; Karim, M R
2016-01-01
Proper maintenance policy can play a vital role for effective investigation of product reliability. Every engineered object such as product, plant or infrastructure needs preventive and corrective maintenance. In this paper we look at a real case study. It deals with the maintenance of hydraulic pumps used in excavators by a mining company. We obtain the data that the owner had collected and carry out an analysis and building models for pump failures. The data consist of both failure and censored lifetimes of the hydraulic pump. Different competitive mixture models are applied to analyze a set of maintenance data of a hydraulic pump. Various characteristics of the mixture models, such as the cumulative distribution function, reliability function, mean time to failure, etc. are estimated to assess the reliability of the pump. Akaike Information Criterion, adjusted Anderson-Darling test statistic, Kolmogrov-Smirnov test statistic and root mean square error are considered to select the suitable models among a set of competitive models. The maximum likelihood estimation method via the EM algorithm is applied mainly for estimating the parameters of the models and reliability related quantities. In this study, it is found that a threefold mixture model (Weibull-Normal-Exponential) fits well for the hydraulic pump failures data set. This paper also illustrates how a suitable statistical model can be applied to estimate the optimum maintenance period at a minimum cost of a hydraulic pump.
Building a maintenance policy through a multi-criterion decision-making model
NASA Astrophysics Data System (ADS)
Faghihinia, Elahe; Mollaverdi, Naser
2012-08-01
A major competitive advantage of production and service systems is establishing a proper maintenance policy. Therefore, maintenance managers should make maintenance decisions that best fit their systems. Multi-criterion decision-making methods can take into account a number of aspects associated with the competitiveness factors of a system. This paper presents a multi-criterion decision-aided maintenance model with three criteria that have more influence on decision making: reliability, maintenance cost, and maintenance downtime. The Bayesian approach has been applied to confront maintenance failure data shortage. Therefore, the model seeks to make the best compromise between these three criteria and establish replacement intervals using Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE II), integrating the Bayesian approach with regard to the preference of the decision maker to the problem. Finally, using a numerical application, the model has been illustrated, and for a visual realization and an illustrative sensitivity analysis, PROMETHEE GAIA (the visual interactive module) has been used. Use of PROMETHEE II and PROMETHEE GAIA has been made with Decision Lab software. A sensitivity analysis has been made to verify the robustness of certain parameters of the model.
Methodology of decreasing software complexity using ontology
NASA Astrophysics Data System (ADS)
DÄ browska-Kubik, Katarzyna
2015-09-01
In this paper a model of web application`s source code, based on the OSD ontology (Ontology for Software Development), is proposed. This model is applied to implementation and maintenance phase of software development process through the DevOntoCreator tool [5]. The aim of this solution is decreasing software complexity of that source code, using many different maintenance techniques, like creation of documentation, elimination dead code, cloned code or bugs, which were known before [1][2]. Due to this approach saving on software maintenance costs of web applications will be possible.
The road maintenance funding models in Indonesia use earmarked tax
NASA Astrophysics Data System (ADS)
Gultom, Tiopan Henry M.; Tamin, Ofyar Z.; Sjafruddin, Ade; Pradono
2017-11-01
One of the solutions to get a sustainable road maintenance fund is to separate road sector revenue from other accounts, afterward, form a specific account for road maintenance. In 2001, Antameng and the Ministry of Public Works proposed a road fund model in Indonesia. Sources of the road funds proposal was a tariff formed on the nominal total tax. The policy of road funds was proposed to finance the road network maintenance of districts and provincials. This research aims to create a policy model of road maintenance funds in Indonesia using an earmarked tax mechanism. The research method is qualitative research, with data collection techniques are triangulation. Interview methods conducted were semi-structured. Strength, Weakness, Opportunities, and Threat from every part of the models were showen on the survey format. Respondents were representative of executives who involved directly against the financing of road maintenance. Validation model conducted by a discussion panel, it was called the Focus Group Discussion (FGD). The FGD involved all selected respondents. Road maintenance financing model that most appropriately applied in Indonesia was a model of revenue source use an earmarked PBBKB, PKB and PPnBM. Revenue collection mechanism was added tariff of registered vehicle tax (PKB), Vehicle Fuel Tax (PBBKB) and the luxury vehicle sales tax (PPnBM). The funds are managed at the provincial level by a public service agency.
NASA Technical Reports Server (NTRS)
Taber, William; Port, Dan
2014-01-01
At the Mission Design and Navigation Software Group at the Jet Propulsion Laboratory we make use of finite exponential based defect models to aid in maintenance planning and management for our widely used critical systems. However a number of pragmatic issues arise when applying defect models for a post-release system in continuous use. These include: how to utilize information from problem reports rather than testing to drive defect discovery and removal effort, practical model calibration, and alignment of model assumptions with our environment.
Developing mobile- and BIM-based integrated visual facility maintenance management system.
Lin, Yu-Cheng; Su, Yu-Chih
2013-01-01
Facility maintenance management (FMM) has become an important topic for research on the operation phase of the construction life cycle. Managing FMM effectively is extremely difficult owing to various factors and environments. One of the difficulties is the performance of 2D graphics when depicting maintenance service. Building information modeling (BIM) uses precise geometry and relevant data to support the maintenance service of facilities depicted in 3D object-oriented CAD. This paper proposes a new and practical methodology with application to FMM using BIM technology. Using BIM technology, this study proposes a BIM-based facility maintenance management (BIMFMM) system for maintenance staff in the operation and maintenance phase. The BIMFMM system is then applied in selected case study of a commercial building project in Taiwan to verify the proposed methodology and demonstrate its effectiveness in FMM practice. Using the BIMFMM system, maintenance staff can access and review 3D BIM models for updating related maintenance records in a digital format. Moreover, this study presents a generic system architecture and its implementation. The combined results demonstrate that a BIMFMM-like system can be an effective visual FMM tool.
NASA Astrophysics Data System (ADS)
Moghaddam, Kamran S.; Usher, John S.
2011-07-01
In this article, a new multi-objective optimization model is developed to determine the optimal preventive maintenance and replacement schedules in a repairable and maintainable multi-component system. In this model, the planning horizon is divided into discrete and equally-sized periods in which three possible actions must be planned for each component, namely maintenance, replacement, or do nothing. The objective is to determine a plan of actions for each component in the system while minimizing the total cost and maximizing overall system reliability simultaneously over the planning horizon. Because of the complexity, combinatorial and highly nonlinear structure of the mathematical model, two metaheuristic solution methods, generational genetic algorithm, and a simulated annealing are applied to tackle the problem. The Pareto optimal solutions that provide good tradeoffs between the total cost and the overall reliability of the system can be obtained by the solution approach. Such a modeling approach should be useful for maintenance planners and engineers tasked with the problem of developing recommended maintenance plans for complex systems of components.
INVENTORY ANALYSIS AND COST ACCOUNTING OF FACILITY MAINTANANCE IN WASTE INCINERATION
NASA Astrophysics Data System (ADS)
Morioka, Tohru; Ozaki, Taira; Kitazume, Keiichi; Yamamoto, Tsukasa
A solid waste incineration plant consists of so many facilities and mechanical parts that it requires periodic careful maintenance of them for stable solid waste management. The current research investigates maintenance costs of the stoker type incinerator and continuous firing plants in detail and develops an accounting model for maintenance of them. This model is able to distinguish among the costs of inspection, repair and renewal by plant with seven process flaw s and three common factors. Parameters based on real data collected by questionnaire surveys give appropriate results in comparison with other plants and enable to apply the model to plants which incinerates 500 - 600 ton solid waste per day.
Development of a Navy Job-Specific Vocational Interest Model
2006-12-01
Enforcement Air Systems Installation/Repair Maritime Interests Applied Mathematics Media Arts Aviation Interests Medical and Dental Services...Technician (AS) 9. Aviation Electronics Technician (AT) 10. Aviation Maintenance Administrationman (AZ) 11. Culinary Specialist (CS) 12. Cryptologic...equipment. 90. Perform preventive and corrective maintenance on state-of-the- art electronic and electromechanical equipment and systems, requiring
A Capacity Forecast Model for Volatile Data in Maintenance Logistics
NASA Astrophysics Data System (ADS)
Berkholz, Daniel
2009-05-01
Maintenance, repair and overhaul processes (MRO processes) are elaborate and complex. Rising demands on these after sales services require reliable production planning and control methods particularly for maintaining valuable capital goods. Downtimes lead to high costs and an inability to meet delivery due dates results in severe contract penalties. Predicting the required capacities for maintenance orders in advance is often difficult due to unknown part conditions unless the goods are actually inspected. This planning uncertainty results in extensive capital tie-up by rising stock levels within the whole MRO network. The article outlines an approach to planning capacities when maintenance data forecasting is volatile. It focuses on the development of prerequisites for a reliable capacity planning model. This enables a quick response to maintenance orders by employing appropriate measures. The information gained through the model is then systematically applied to forecast both personnel capacities and the demand for spare parts. The improved planning reliability can support MRO service providers in shortening delivery times and reducing stock levels in order to enhance the performance of their maintenance logistics.
Developing Mobile- and BIM-Based Integrated Visual Facility Maintenance Management System
Su, Yu-Chih
2013-01-01
Facility maintenance management (FMM) has become an important topic for research on the operation phase of the construction life cycle. Managing FMM effectively is extremely difficult owing to various factors and environments. One of the difficulties is the performance of 2D graphics when depicting maintenance service. Building information modeling (BIM) uses precise geometry and relevant data to support the maintenance service of facilities depicted in 3D object-oriented CAD. This paper proposes a new and practical methodology with application to FMM using BIM technology. Using BIM technology, this study proposes a BIM-based facility maintenance management (BIMFMM) system for maintenance staff in the operation and maintenance phase. The BIMFMM system is then applied in selected case study of a commercial building project in Taiwan to verify the proposed methodology and demonstrate its effectiveness in FMM practice. Using the BIMFMM system, maintenance staff can access and review 3D BIM models for updating related maintenance records in a digital format. Moreover, this study presents a generic system architecture and its implementation. The combined results demonstrate that a BIMFMM-like system can be an effective visual FMM tool. PMID:24227995
Homeostatic maintenance via degradation and repair of elastic fibers under tension
NASA Astrophysics Data System (ADS)
Alves, Calebe; Araújo, Ascanio D.; Oliveira, Cláudio L. N.; Imsirovic, Jasmin; Bartolák-Suki, Erzsébet; Andrade, José S.; Suki, Béla
2016-06-01
Cellular maintenance of the extracellular matrix requires an effective regulation that balances enzymatic degradation with the repair of collagen fibrils and fibers. Here, we investigate the long-term maintenance of elastic fibers under tension combined with diffusion of general degradative and regenerative particles associated with digestion and repair processes. Computational results show that homeostatic fiber stiffness can be achieved by assuming that cells periodically probe fiber stiffness to adjust the production and release of degradative and regenerative particles. However, this mechanism is unable to maintain a homogeneous fiber. To account for axial homogeneity, we introduce a robust control mechanism that is locally governed by how the binding affinity of particles is modulated by mechanical forces applied to the ends of the fiber. This model predicts diameter variations along the fiber that are in agreement with the axial distribution of collagen fibril diameters obtained from scanning electron microscopic images of normal rat thoracic aorta. The model predictions match the experiments only when the applied force on the fiber is in the range where the variance of local stiffness along the fiber takes a minimum value. Our model thus predicts that the biophysical properties of the fibers play an important role in the long-term regulatory maintenance of these fibers.
NASA Astrophysics Data System (ADS)
Amrina, E.; Yulianto, A.
2018-03-01
Sustainable maintenance is a new challenge for manufacturing companies to realize sustainable development. In this paper, an interpretive structural model is developed to evaluate sustainable maintenance in the rubber industry. The initial key performance indicators (KPIs) is identified and derived from literature and then validated by academic and industry experts. As a result, three factors of economic, social, and environmental dividing into a total of thirteen indicators are proposed as the KPIs for sustainable maintenance evaluation in rubber industry. Interpretive structural modeling (ISM) methodology is applied to develop a network structure model of the KPIs consisting of three levels. The results show the economic factor is regarded as the basic factor, the social factor as the intermediate factor, while the environmental factor indicated to be the leading factor. Two indicators of social factor i.e. labor relationship, and training and education have both high driver and dependence power, thus categorized as the unstable indicators which need further attention. All the indicators of environmental factor and one indicator of social factor are indicated as the most influencing indicator. The interpretive structural model hoped can aid the rubber companies in evaluating sustainable maintenance performance.
Applying Psychological Theories to Promote Long-Term Maintenance of Health Behaviors
Joseph, Rodney P.; Daniel, Casey L.; Thind, Herpreet; Benitez, Tanya J.; Pekmezi, Dori
2014-01-01
Behavioral health theory provides a framework for researchers to design, implement, and evaluate the effects of health promotion programs. However, limited research has examined theories used in interventions to promote long-term maintenance of health behaviors. The purpose of this review was to evaluate the available literature and identify prominent behavioral health theories used in intervention research to promote maintenance of health behaviors. We reviewed theories used in intervention research assessing long-term maintenance (≥ 6 months post-intervention) of physical activity, weight loss, and smoking cessation. Five prominent behavioral theories were referenced by the 34 studies included in the review: Self-Determination Theory, Theory of Planned Behavior, Social Cognitive Theory, Transtheoretical Model, and Social Ecological Model. Descriptions and examples of applications of these theories are provided. Implications for future research are discussed. PMID:28217036
77 FR 18970 - Airworthiness Directives; Bell Helicopter Textron Canada Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-29
... Model 407 Maintenance Manual and applied during manufacturing was incorrect and exceeded the torque... hardware (attachment hardware), and perform initial and recurring determinations of [[Page 18971
Maintenance of Social Anxiety in Stuttering: A Cognitive-Behavioral Model.
Iverach, Lisa; Rapee, Ronald M; Wong, Quincy J J; Lowe, Robyn
2017-05-17
Stuttering is a speech disorder frequently accompanied by anxiety in social-evaluative situations. A growing body of research has confirmed a significant rate of social anxiety disorder among adults who stutter. Social anxiety disorder is a chronic and disabling anxiety disorder associated with substantial life impairment. Several influential models have described cognitive-behavioral factors that contribute to the maintenance of social anxiety in nonstuttering populations. The purpose of the present article is to apply these leading models to the experience of social anxiety for people who stutter. Components from existing models were applied to stuttering in order to determine cognitive-behavioral processes that occur before, during, and after social-evaluative situations, which may increase the likelihood of stuttering-related social fears persisting. Maintenance of social anxiety in stuttering may be influenced by a host of interrelated factors, including fear of negative evaluation, negative social-evaluative cognitions, attentional biases, self-focused attention, safety behaviors, and anticipatory and postevent processing. Given the chronic nature of social anxiety disorder, identifying factors that contribute to the persistence of stuttering-related social fears has the potential to inform clinical practice and the development of psychological treatment programs to address the speech and psychological needs of people who stutter with social anxiety.
NASA Astrophysics Data System (ADS)
Zhang, Ding; Zhang, Yingjie
2017-09-01
A framework for reliability and maintenance analysis of job shop manufacturing systems is proposed in this paper. An efficient preventive maintenance (PM) policy in terms of failure effects analysis (FEA) is proposed. Subsequently, reliability evaluation and component importance measure based on FEA are performed under the PM policy. A job shop manufacturing system is applied to validate the reliability evaluation and dynamic maintenance policy. Obtained results are compared with existed methods and the effectiveness is validated. Some vague understandings for issues such as network modelling, vulnerabilities identification, the evaluation criteria of repairable systems, as well as PM policy during manufacturing system reliability analysis are elaborated. This framework can help for reliability optimisation and rational maintenance resources allocation of job shop manufacturing systems.
NASA Astrophysics Data System (ADS)
Wang, Zhao-Qiang; Hu, Chang-Hua; Si, Xiao-Sheng; Zio, Enrico
2018-02-01
Current degradation modeling and remaining useful life prediction studies share a common assumption that the degrading systems are not maintained or maintained perfectly (i.e., to an as-good-as new state). This paper concerns the issues of how to model the degradation process and predict the remaining useful life of degrading systems subjected to imperfect maintenance activities, which can restore the health condition of a degrading system to any degradation level between as-good-as new and as-bad-as old. Toward this end, a nonlinear model driven by Wiener process is first proposed to characterize the degradation trajectory of the degrading system subjected to imperfect maintenance, where negative jumps are incorporated to quantify the influence of imperfect maintenance activities on the system's degradation. Then, the probability density function of the remaining useful life is derived analytically by a space-scale transformation, i.e., transforming the constructed degradation model with negative jumps crossing a constant threshold level to a Wiener process model crossing a random threshold level. To implement the proposed method, unknown parameters in the degradation model are estimated by the maximum likelihood estimation method. Finally, the proposed degradation modeling and remaining useful life prediction method are applied to a practical case of draught fans belonging to a kind of mechanical systems from steel mills. The results reveal that, for a degrading system subjected to imperfect maintenance, our proposed method can obtain more accurate remaining useful life predictions than those of the benchmark model in literature.
NASA Astrophysics Data System (ADS)
Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.
2016-06-01
The growing interest in technicians' workloads research is probably associated with the recent surge in competition. This was prompted by unprecedented technological development that triggers changes in customer tastes and preferences for industrial goods. In a quest for business improvement, this worldwide intense competition in industries has stimulated theories and practical frameworks that seek to optimise performance in workplaces. In line with this drive, the present paper proposes an optimisation model which considers technicians' reliability that complements factory information obtained. The information used emerged from technicians' productivity and earned-values using the concept of multi-objective modelling approach. Since technicians are expected to carry out routine and stochastic maintenance work, we consider these workloads as constraints. The influence of training, fatigue and experiential knowledge of technicians on workload management was considered. These workloads were combined with maintenance policy in optimising reliability, productivity and earned-values using the goal programming approach. Practical datasets were utilised in studying the applicability of the proposed model in practice. It was observed that our model was able to generate information that practicing maintenance engineers can apply in making more informed decisions on technicians' management.
40 CFR 1068.120 - What requirements must I follow to rebuild engines?
Code of Federal Regulations, 2010 CFR
2010-07-01
... recordkeeping requirements in paragraphs (j) and (k) of this section apply only to businesses. For maintenance... in its certified configuration. Identify the model year of the resulting engine configuration. You... later model year. You may also rebuild it to a certified configuration from an earlier model year as...
Measuring the performance of maintenance service outsourcing.
Cruz, Antonio Miguel; Rincon, Adriana Maria Rios; Haugan, Gregory L
2013-01-01
The aims of this paper are (1) to identify the characteristics of maintenance service providers that directly impact maintenance service quality, using 18 independent covariables; (2) to quantify the change in risk these covariables present to service quality, measured in terms of equipment turnaround time (TAT). A survey was applied to every maintenance service provider (n = 19) for characterization purposes. The equipment inventory was characterized, and the TAT variable recorded and monitored for every work order of each service provider (N = 1,025). Finally, the research team conducted a statistical analysis to accomplish the research objectives. The results of this study offer strong empirical evidence that the most influential variables affecting the quality of maintenance service performance are the following: type of maintenance, availability of spare parts in the country, user training, technological complexity of the equipment, distance between the company and the hospital, and the number of maintenance visits performed by the company. The strength of the results obtained by the Cox model built are supported by the measure of the Rp,e(2) = 0.57 with a value of Rp,e= 0.75. Thus, the model explained 57% of the variation in equipment TAT, with moderate high positive correlation between the dependent variable (TAT) and independent variables.
Social anxiety in pre-adolescent children: What do we know about maintenance?
Halldorsson, Brynjar; Creswell, Cathy
2017-12-01
The cognitive theory of social anxiety disorder (SAD) is one of the most widely accepted accounts of the maintenance of the disorder in adults, yet it remains unknown if, or to what extent, the same cognitive and behavioral maintenance mechanisms that occur in adult SAD also apply to SAD among pre-adolescent children. In contrast to the adult literature, current models of SAD in children mostly account for etiology and maintenance processes are given limited attention. Consequently, their clinical utility for the treatment of SAD in children may be limited. This narrative review, first, critically examines the different theoretical conceptualizations of the maintenance of social anxiety in the child and adult literature and illustrates how these have resulted in different treatment approaches and clinical understanding. Second, it reviews the available evidence relating to hypotheses about the maintenance of SAD in children as derived from adult cognitive and etiological models. Third, it highlights the need to attend directly to child specific maintenance mechanisms in SAD, to draw on cognitive theory, and to account for the influence of childhood-specific contextual (e.g. family and school-based interactions) and developmental factors on children's social experiences. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Code of Federal Regulations, 2012 CFR
2012-07-01
... apply to the selection and maintenance of electronic records storage media for permanent records? 1236... What additional requirements apply to the selection and maintenance of electronic records storage media for permanent records? (a) Agencies must maintain the storage and test areas for electronic records...
Code of Federal Regulations, 2014 CFR
2014-07-01
... apply to the selection and maintenance of electronic records storage media for permanent records? 1236... What additional requirements apply to the selection and maintenance of electronic records storage media for permanent records? (a) Agencies must maintain the storage and test areas for electronic records...
Cheung, C Y Maurice; Williams, Thomas C R; Poolman, Mark G; Fell, David A; Ratcliffe, R George; Sweetlove, Lee J
2013-09-01
Flux balance models of metabolism generally utilize synthesis of biomass as the main determinant of intracellular fluxes. However, the biomass constraint alone is not sufficient to predict realistic fluxes in central heterotrophic metabolism of plant cells because of the major demand on the energy budget due to transport costs and cell maintenance. This major limitation can be addressed by incorporating transport steps into the metabolic model and by implementing a procedure that uses Pareto optimality analysis to explore the trade-off between ATP and NADPH production for maintenance. This leads to a method for predicting cell maintenance costs on the basis of the measured flux ratio between the oxidative steps of the oxidative pentose phosphate pathway and glycolysis. We show that accounting for transport and maintenance costs substantially improves the accuracy of fluxes predicted from a flux balance model of heterotrophic Arabidopsis cells in culture, irrespective of the objective function used in the analysis. Moreover, when the new method was applied to cells under control, elevated temperature and hyper-osmotic conditions, only elevated temperature led to a substantial increase in cell maintenance costs. It is concluded that the hyper-osmotic conditions tested did not impose a metabolic stress, in as much as the metabolic network is not forced to devote more resources to cell maintenance. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.
2015-09-17
impact influenced by its internal and external supply chain activities. This starts with understanding how we currently apply advanced analytic techniques... minimalistic model provides for sufficient degrees of freedom to guard against overfitting. Second, to guard against the possibility of an over-trained model in... starting with 1*. 201* All Military compensation EEICs starting with 201*. Facility Sustainment 52* & 56* All facility maintenance, repair and minor
Parasites and deleterious mutations: interactions influencing the evolutionary maintenance of sex.
Park, A W; Jokela, J; Michalakis, Y
2010-05-01
The restrictive assumptions associated with purely genetic and purely ecological mechanisms suggest that neither of the two forces, in isolation, can offer a general explanation for the evolutionary maintenance of sex. Consequently, attention has turned to pluralistic models (i.e. models that apply both ecological and genetic mechanisms). Existing research has shown that combining mutation accumulation and parasitism allows restrictive assumptions about genetic and parasite parameter values to be relaxed while still predicting the maintenance of sex. However, several empirical studies have shown that deleterious mutations and parasitism can reduce fitness to a greater extent than would be expected if the two acted independently. We show how interactions between these genetic and ecological forces can completely reverse predictions about the evolution of reproductive modes. Moreover, we demonstrate that synergistic interactions between infection and deleterious mutations can render sex evolutionarily stable even when there is antagonistic epistasis among deleterious mutations, thereby widening the conditions for the evolutionary maintenance of sex.
Stages and Processes of Self-Change of Smoking: Toward an Integrative Model of Change.
ERIC Educational Resources Information Center
Prochaska, James O.; DiClemente, Carlo C.
1983-01-01
Applied an integrative model of change to the study of subjects (N=872) changing their smoking habits on their own. The subjects represented five stages of change: (1) precontemplation; (2) contemplation; (3) action; (4) maintenance; and (5) relapse. Relapsers' responses were a combination of contemplation and action. (JAC)
Additive Manufacturing (3D Printing) Aircraft Parts and Tooling at the Maintenance Group Level
The purpose of this research was to evaluate the effectiveness of additive manufacturing (AM) or 3D printing for the Air Force aircraft maintenance...case study of the 552d MXGs 3D printing operation explores their use of a Fused Deposition Modeling (FDM) thermoplastic material to manufacture parts...by applying the case study’s analysis toward a proof of concept, producing a C-130J Aft Cargo Door Rub Strip for 3D printing . The study concluded by
NASA Astrophysics Data System (ADS)
Hamdi, Hadiwardoyo, Sigit P.; Correia, A. Gomes; Pereira, Paulo
2017-06-01
A road network requires timely maintenance to keep the road surface in good condition onward better services to improve accessibility and mobility. Strategies and maintenance techniques must be chosen in order to maximize road service level through cost-effective interventions. This approach requires an updated database, which the road network in Indonesia is supported by a manual and visual survey, also using NAASRA profiler. Furthermore, in this paper, the deterministic model of deterioration was used. This optimization model uses life cycle cost analysis (LCCA), applied in an integrated manner, using IRI indicator, and allows determining the priority of treatment, type of treatment and its relation to the cost. The purpose of this paper was focussed on the aspects of road maintenance management, i.e., maintenance optimization models for different levels of traffic and various initial of road distress conditions on the national road network in Indonesia. The implementation of Integrated Road Management System (IRMS) can provide a solution to the problem of cost constraints in the maintenance of the national road network. The results from this study found that as the lowest as agency cost, it will affect the increasing of user cost. With the achievement of the target plan scenario Pl000 with initial value IRI 2, it was found that the routine management throughout the year and in early reconstruction and periodic maintenance with a 30 mm thick overlay, will simultaneously provide a higher net benefit value and has the lowest total cost of transportation.
Knowledge, attitudes, and behavior concerning nutrition and physical activity in Mexican children.
Escalante-Guerrero, Claudia Susana; De la Roca-Chiapas, José María; Macías-Cervantes, Maciste Habacuc
2012-03-01
To identify the stages of behavior change and the knowledge, attitudes, and habits concerning nutrition and physical activity in Mexican children. A survey was applied to 48 children from 10 years old to obtain data. Stages of behavior change were classified according to the transtheoretical model. For food habits, 31% were in precontemplation, 17% in contemplation, 10% in preparation, 40% in action, and 2% in maintenance. For physical activity, 12% were in precontemplation, 15% in contemplation, 29% in preparation, 42% in action, and 2% in maintenance. It is important to consider the stages of behavior change to plan strategies of educational models.
Application Research of Fault Tree Analysis in Grid Communication System Corrective Maintenance
NASA Astrophysics Data System (ADS)
Wang, Jian; Yang, Zhenwei; Kang, Mei
2018-01-01
This paper attempts to apply the fault tree analysis method to the corrective maintenance field of grid communication system. Through the establishment of the fault tree model of typical system and the engineering experience, the fault tree analysis theory is used to analyze the fault tree model, which contains the field of structural function, probability importance and so on. The results show that the fault tree analysis can realize fast positioning and well repairing of the system. Meanwhile, it finds that the analysis method of fault tree has some guiding significance to the reliability researching and upgrading f the system.
Value centric approaches to the design, operations and maintenance of wind turbines
NASA Astrophysics Data System (ADS)
Khadabadi, Madhur Aravind
Wind turbine maintenance is emerging as an unexpectedly high component of turbine operating cost, and there is an increasing interest in managing this cost. This thesis presents an alternative view of maintenance as a value-driver, and develops an optimization algorithm to evaluate the value delivered by different maintenance techniques. I view maintenance as an operation that moves the turbine to an improved state in which it can generate more power and, thus, earn more revenue. To implement this approach, I model the stochastic deterioration of the turbine in two dimensions: the deterioration rate, and the extent of deterioration, and then use maintenance to improve the state of the turbine. The value of the turbine is the difference between the revenue from to the power generation and the costs incurred in operation and maintenance. With a focus on blade deterioration, I evaluate the value delivered by implementing two different maintenance schemes, predictive maintenance and scheduled maintenance. An example of predictive maintenance technique is the use of Condition Monitoring Systems to precisely detect deterioration. I model Condition Monitoring System (CMS) of different degrees of fidelity, where a higher fidelity CMS would allow the blade state to be determined with a higher precision. The same model is then applied for the scheduled maintenance technique. The improved state information obtained from these techniques is then used to derive an optimal maintenance strategy. The difference between the value of the turbine with and without the inspection type can be interpreted as the value of the inspection. The results indicate that a higher fidelity (and more expensive) inspection method does not necessarily yield the highest value, and, that there is an optimal level of fidelity that results in maximum value. The results also aim to inform the operator of the impact of regional parameters such as wind speed, variance and maintenance costs to the optimal maintenance strategy. The contributions of this work are twofold. First, I present a practical approach to wind turbine valuation that takes operating and market conditions into account. This work should therefore be useful to wind farm operators, investors and decision makers. Second, I show how the value of a maintenance scheme can be explicitly assessed for different conditions.
DOT National Transportation Integrated Search
2003-04-01
The Louisiana Department of Transportation and Development (LADOTD) is interested in applying the Federal Highway Administration=s (FHWA) life cycle cost analysis procedures and model to large roadway construction, maintenance, and rehabilitation pro...
Using Decision Analysis to Select Facility Maintenance Management Information Systems
2010-03-01
efficient way possible. Many of today’s maintenance managers thus apply computerized tools that come in the form of information systems that assist in... apply to effectively select a maintenance management information system that enables them to meet the needs of their customers. 3 1.2 Background...recession of the early 1990s. During this time, companies downsized their white-collar workforce performing daily operation and maintenance functions
Impact of forest maintenance on water shortages: Hydrologic modeling and effects of climate change.
Luo, Pingping; Zhou, Meimei; Deng, Hongzhang; Lyu, Jiqiang; Cao, Wenqiang; Takara, Kaoru; Nover, Daniel; Geoffrey Schladow, S
2018-02-15
The importance of water quantity for domestic and industrial water supply, agriculture, and the economy more broadly has led to the development of many water quantity assessment methods. In this study, surface flow and soil water in the forested upper reaches of the Yoshino River are compared using a distributed hydrological model with Forest Maintenance Module under two scenarios; before and after forest maintenance. We also examine the impact of forest maintenance on these variables during extreme droughts. Results show that surface flow and soil water increased after forest maintenance. In addition, projections of future water resources were estimated using a hydrological model and the output from a 20km mesh Global Climate Model (GCM20). River discharge for the near-future (2015-2039) is similar to that of the present (1979-2003). Estimated river discharge for the future (2075-2099) was found to be substantially more extreme than in the current period, with 12m 3 /s higher peak discharge in August and 7m 3 /s lower in July compared to the discharges of the present period. Soil water for the future is estimated to be lower than for the present and near future in May. The methods discussed in this study can be applied in other regions and the results help elucidate the impact of forests and climate change on water resources. Copyright © 2017 Elsevier B.V. All rights reserved.
Walter, D
2000-08-01
More than 90% of the critical skills that an aviation maintenance technician uses are acquired through on-the-job training (OJT). Yet many aviation maintenance technicians rely on a 'degenerating buddy system', 'follow Joe around', or unstructured approach to OJT. Many aspects of the aviation maintenance environment point to the need for a structured OJT program, but perhaps the most significant is the practice of job bidding which can create rapid turnover of technicians. The task analytic training system (TATS), a model for developing team-driven structured OJT was developed by the author, and first introduced in Boeing Commercial Airplane Group to provide competency-based OJT for aviation maintenance and inspection personnel. The goal of the model was not only to provide a comprehensive, highly structured training system that could be applied to any maintenance and inspection task, but also to improve team coordination, attitude and morale. The first goal was accomplished by following the systems eight-step process, the latter through incorporating human factors principles such as decision making, communication, team building and conflict resolution into the process itself. In general, the process helps to instill mutual respect and trust, enhance goal-directed behavior, strengthen technicians' self-esteem and responsiveness to new ideas and encourage technicians to make worthwhile contributions. The theoretical background of the model is addressed by illustrating how the proven training methodologies of job task analysis and job instruction training are blended with human factors principles resulting in a unique team-driven approach to training. The paper discusses major elements of the model including needs identification, outlining targeted jobs, writing and verifying training procedures, an approval system, sequencing of training, certifying trainers, implementing, employing tracking mechanisms, evaluating, and establishing a maintenance/audit plan. Relevance to industry. TATS has been successfully installed in several maintenance and inspection areas of The Boeing Company. Four major U.S. airlines--United Airlines, TransWorld Airlines, Northwest Airlines, and USAirways have participated in two years of development and field testing in their maintenance operations (assisted by the author and Dr. Barbara Kanki of NASA Ames Research Center).
Fontecha, John E; Akhavan-Tabatabaei, Raha; Duque, Daniel; Medaglia, Andrés L; Torres, María N; Rodríguez, Juan Pablo
In this work we tackle the problem of planning and scheduling preventive maintenance (PM) of sediment-related sewer blockages in a set of geographically distributed sites that are subject to non-deterministic failures. To solve the problem, we extend a combined maintenance and routing (CMR) optimization approach which is a procedure based on two components: (a) first a maintenance model is used to determine the optimal time to perform PM operations for each site and second (b) a mixed integer program-based split procedure is proposed to route a set of crews (e.g., sewer cleaners, vehicles equipped with winches or rods and dump trucks) in order to perform PM operations at a near-optimal minimum expected cost. We applied the proposed CMR optimization approach to two (out of five) operative zones in the city of Bogotá (Colombia), where more than 100 maintenance operations per zone must be scheduled on a weekly basis. Comparing the CMR against the current maintenance plan, we obtained more than 50% of cost savings in 90% of the sites.
1987-09-01
Edition,. Fail 1986. 33. Neter, John et al. Applied Linear Regression MoceL. Homewood IL: Richard D. Irwin, Incorporated, iJ83. 34. NovicK, David... Linear Regression Models (33) then, for each sample observation (X fh, the method of least squares considers the deviation of Yubms from its expected value...for finding good estimators of b - b5 * In -2raer to explain the procedure, the model Yubms = b0 + b!xfh will be discussed. According to Applied
77 FR 57005 - Airworthiness Directives; Bell Helicopter Textron Canada Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-17
... tailboom-attachment hardware (attachment hardware), and perform initial and recurring determinations of the... bolts specified in the BHTC Model 407 Maintenance Manual and applied during manufacturing was incorrect... require replacing attachment hardware and performing initial and recurring determinations of the torque on...
The Effects of Taxes on the Supply of Labor: with Special Reference to Income Maintenance Programs.
ERIC Educational Resources Information Center
Boskin, Michael Jay
The study builds a theoretical model of the interdependence of the labor supply decisions of family members and applies it to data from the 1967 survey of Economic Opportunity to estimate labor supply curves for population subgroups. The three relevant variables measured are labor supply, wages, and income. The model gives an estimate of the…
United States Marine Corps Motor Transport Mechanic-to-Equipment Ratio
time motor transport equipment remains in maintenance at the organizational command level. This thesis uses a discrete event simulation model of the...applied to a single experiment that allows for assessment of risk of not achieving the objective. Inter-arrival time, processing time, work schedule
NASA Astrophysics Data System (ADS)
Wang, Yunzhi; Qiu, Yuchen; Thai, Theresa; More, Kathleen; Ding, Kai; Liu, Hong; Zheng, Bin
2016-03-01
How to rationally identify epithelial ovarian cancer (EOC) patients who will benefit from bevacizumab or other antiangiogenic therapies is a critical issue in EOC treatments. The motivation of this study is to quantitatively measure adiposity features from CT images and investigate the feasibility of predicting potential benefit of EOC patients with or without receiving bevacizumab-based chemotherapy treatment using multivariate statistical models built based on quantitative adiposity image features. A dataset involving CT images from 59 advanced EOC patients were included. Among them, 32 patients received maintenance bevacizumab after primary chemotherapy and the remaining 27 patients did not. We developed a computer-aided detection (CAD) scheme to automatically segment subcutaneous fat areas (VFA) and visceral fat areas (SFA) and then extracted 7 adiposity-related quantitative features. Three multivariate data analysis models (linear regression, logistic regression and Cox proportional hazards regression) were performed respectively to investigate the potential association between the model-generated prediction results and the patients' progression-free survival (PFS) and overall survival (OS). The results show that using all 3 statistical models, a statistically significant association was detected between the model-generated results and both of the two clinical outcomes in the group of patients receiving maintenance bevacizumab (p<0.01), while there were no significant association for both PFS and OS in the group of patients without receiving maintenance bevacizumab. Therefore, this study demonstrated the feasibility of using quantitative adiposity-related CT image features based statistical prediction models to generate a new clinical marker and predict the clinical outcome of EOC patients receiving maintenance bevacizumab-based chemotherapy.
Optimal maintenance of a multi-unit system under dependencies
NASA Astrophysics Data System (ADS)
Sung, Ho-Joon
The availability, or reliability, of an engineering component greatly influences the operational cost and safety characteristics of a modern system over its life-cycle. Until recently, the reliance on past empirical data has been the industry-standard practice to develop maintenance policies that provide the minimum level of system reliability. Because such empirically-derived policies are vulnerable to unforeseen or fast-changing external factors, recent advancements in the study of topic on maintenance, which is known as optimal maintenance problem, has gained considerable interest as a legitimate area of research. An extensive body of applicable work is available, ranging from those concerned with identifying maintenance policies aimed at providing required system availability at minimum possible cost, to topics on imperfect maintenance of multi-unit system under dependencies. Nonetheless, these existing mathematical approaches to solve for optimal maintenance policies must be treated with caution when considered for broader applications, as they are accompanied by specialized treatments to ease the mathematical derivation of unknown functions in both objective function and constraint for a given optimal maintenance problem. These unknown functions are defined as reliability measures in this thesis, and theses measures (e.g., expected number of failures, system renewal cycle, expected system up time, etc.) do not often lend themselves to possess closed-form formulas. It is thus quite common to impose simplifying assumptions on input probability distributions of components' lifetime or repair policies. Simplifying the complex structure of a multi-unit system to a k-out-of-n system by neglecting any sources of dependencies is another commonly practiced technique intended to increase the mathematical tractability of a particular model. This dissertation presents a proposal for an alternative methodology to solve optimal maintenance problems by aiming to achieve the same end-goals as Reliability Centered Maintenance (RCM). RCM was first introduced to the aircraft industry in an attempt to bridge the gap between the empirically-driven and theory-driven approaches to establishing optimal maintenance policies. Under RCM, qualitative processes that enable the prioritizing of functions based on the criticality and influence would be combined with mathematical modeling to obtain the optimal maintenance policies. Where this thesis work deviates from RCM is its proposal to directly apply quantitative processes to model the reliability measures in optimal maintenance problem. First, Monte Carlo (MC) simulation, in conjunction with a pre-determined Design of Experiments (DOE) table, can be used as a numerical means of obtaining the corresponding discrete simulated outcomes of the reliability measures based on the combination of decision variables (e.g., periodic preventive maintenance interval, trigger age for opportunistic maintenance, etc.). These discrete simulation results can then be regressed as Response Surface Equations (RSEs) with respect to the decision variables. Such an approach to represent the reliability measures with continuous surrogate functions (i.e., the RSEs) not only enables the application of the numerical optimization technique to solve for optimal maintenance policies, but also obviates the need to make mathematical assumptions or impose over-simplifications on the structure of a multi-unit system for the sake of mathematical tractability. The applicability of the proposed methodology to a real-world optimal maintenance problem is showcased through its application to a Time Limited Dispatch (TLD) of Full Authority Digital Engine Control (FADEC) system. In broader terms, this proof-of-concept exercise can be described as a constrained optimization problem, whose objective is to identify the optimal system inspection interval that guarantees a certain level of availability for a multi-unit system. A variety of reputable numerical techniques were used to model the problem as accurately as possible, including algorithms for the MC simulation, imperfect maintenance model from quasi renewal processes, repair time simulation, and state transition rules. Variance Reduction Techniques (VRTs) were also used in an effort to enhance MC simulation efficiency. After accurate MC simulation results are obtained, the RSEs are generated based on the goodness-of-fit measure to yield as parsimonious model as possible to construct the optimization problem. Under the assumption of constant failure rate for lifetime distributions, the inspection interval from the proposed methodology was found to be consistent with the one from the common approach used in industry that leverages Continuous Time Markov Chain (CTMC). While the latter does not consider maintenance cost settings, the proposed methodology enables an operator to consider different types of maintenance cost settings, e.g., inspection cost, system corrective maintenance cost, etc., to result in more flexible maintenance policies. When the proposed methodology was applied to the same TLD of FADEC example, but under the more generalized assumption of strictly Increasing Failure Rate (IFR) for lifetime distribution, it was shown to successfully capture component wear-out, as well as the economic dependencies among the system components.
INTEGRATED AIR POLLUTION CONTROL SYSTEM VERSION 5.0 - VOLUME 3: PROGRAMMER'S MAINTENANCE MANUAL
The three volume report and two diskettes document the Integrated Air Pollution Control System (IAPCS), developed for the U.S. EPA to estimate costs and performance for emission control systems applied to coal-fired utility boilers. The model can project a material balance, an eq...
Kelly, Andrew John; Fausset, Cara Bailey; Rogers, Wendy; Fisk, Arthur D
2014-12-01
This study examined potential issues faced by older adults in managing their homes and their proposed solutions for overcoming hypothetical difficulties. Forty-four diverse, independently living older adults (66-85) participated in structured group interviews in which they discussed potential solutions to manage difficulties presented in four scenarios: perceptual, mobility, physical, and cognitive difficulties. The proposed solutions were classified using the Selection, Optimization, and Compensation (SOC) model. Participants indicated they would continue performing most tasks and reported a range of strategies to manage home maintenance challenges. Most participants reported that they would manage home maintenance challenges using compensation; the most frequently mentioned compensation strategy was using tools and technologies. There were also differences across the scenarios: Optimization was discussed most frequently with perceptual and cognitive difficulty scenarios. These results provide insights into supporting older adults' potential needs for aging-in-place and provide evidence of the value of the SOC model in applied research. © The Author(s) 2012.
Gong, Yaping; Law, Kenneth S; Chang, Song; Xin, Katherine R
2009-01-01
In this study, the authors developed a dual-concern (i.e., maintenance and performance) model of human resources (HR) management. The authors identified commonly examined HR practices that apply to the middle manager level and classified them into the maintenance- and performance-oriented HR subsystems. The authors found support for the 2-factor model on the basis of responses from 2,148 managers from 463 firms operating in China. Regression results indicate that the performance-oriented HR subsystems had a positive relationship with firm performance and that the relationship was mediated by middle managers' affective commitment to the firm. The maintenance-oriented HR subsystems had a positive relationship with middle managers' continuance commitment but not with their affective commitment and firm performance. This study contributes to the understanding of how HR practices relate to firm performance and offers an improved test of the argument that valuable and firm-specific HR provide a source of competitive advantage. (PsycINFO Database Record (c) 2009 APA, all rights reserved).
Maintenance Audit through Value Analysis Technique: A Case Study
NASA Astrophysics Data System (ADS)
Carnero, M. C.; Delgado, S.
2008-11-01
The increase in competitiveness, technological changes and the increase in the requirements of quality and service have forced a change in the design and application of maintenance, as well as the way in which it is considered within the managerial strategy. There are numerous maintenance activities that must be developed in a service company. As a result the maintenance functions as a whole have to be outsourced. Nevertheless, delegating this subject to specialized personnel does not exempt the company from responsibilities, but rather leads to the need for control of each maintenance activity. In order to achieve this control and to evaluate the efficiency and effectiveness of the company it is essential to carry out an audit that diagnoses the problems that could develop. In this paper a maintenance audit applied to a service company is developed. The methodology applied is based on the expert systems. The expert system by means of rules uses the weighting technique SMART and value analysis to obtain the weighting between the decision functions and between the alternatives. The expert system applies numerous rules and relations between different variables associated with the specific maintenance functions, to obtain the maintenance state by sections and the general maintenance state of the enterprise. The contributions of this paper are related to the development of a maintenance audit in a service enterprise, in which maintenance is not generally considered a strategic subject and to the integration of decision-making tools such as the weighting technique SMART with value analysis techniques, typical in the design of new products, in the area of the rule-based expert systems.
Advanced training of specialists in area of fiber-optic communication lines maintenance
NASA Astrophysics Data System (ADS)
Andreev, Vladimir A.; Voronkov, Andrey A.; Bukashkin, Sergey A.; Buzova, Maria A.
2017-04-01
The paper considers the concept of fiber-optic communication lines (FOCL) maintenance. Performance criterion of FOCL technical maintenance was proposed. For the first time the algorithm for evaluation of the FOCL maintenance efficiency at telecommunication specialists training was applied.
Strategy on energy saving reconstruction of distribution networks based on life cycle cost
NASA Astrophysics Data System (ADS)
Chen, Xiaofei; Qiu, Zejing; Xu, Zhaoyang; Xiao, Chupeng
2017-08-01
Because the actual distribution network reconstruction project funds are often limited, the cost-benefit model and the decision-making method are crucial for distribution network energy saving reconstruction project. From the perspective of life cycle cost (LCC), firstly the research life cycle is determined for the energy saving reconstruction of distribution networks with multi-devices. Then, a new life cycle cost-benefit model for energy-saving reconstruction of distribution network is developed, in which the modification schemes include distribution transformers replacement, lines replacement and reactive power compensation. In the operation loss cost and maintenance cost area, the operation cost model considering the influence of load season characteristics and the maintenance cost segmental model of transformers are proposed. Finally, aiming at the highest energy saving profit per LCC, a decision-making method is developed while considering financial and technical constraints as well. The model and method are applied to a real distribution network reconstruction, and the results prove that the model and method are effective.
Experimental adoption of RCM in EDF substations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heroin, G.; Aupied, J.; Sanchis, G.
1996-08-01
EDF, after testing Reliability Centered Maintenance (RCM) on systems used in nuclear power plants, has now successfully extended RCM to all of its nuclear power plants. In the light of this experience, EDF has committed itself to a pilot study on a line bay of a 400 kV substation in 1992. The RCM method as applied benefited from EDF`s policy of maintenance, introduced five years ago on all substations, which has enhanced prospects of reliability. The original feature in the selection of maintenance tasks was that it brought into play two criteria for failure assessment - frequency and seriousness -more » and two criteria for maintenance task selection - efficiency and facility. The final outcome of RCM as applied to substation maintenance is to categorize maintenance tasks into: (1) essential maintenance tasks, (2) optional tasks, depending on the type and location of the substation, as well as on factors relating to local management of maintenance policy, and (3) unnecessary tasks.« less
Hjalte, F; Asseburg, C; Tennvall, G R
2010-04-01
Atopic dermatitis (AD) affects health and quality of life and it has great impact on both health-care costs and costs to the society. The objective of this study was to develop a model to analyse the cost-effectiveness of a barrier-strengthening moisturizing cream as maintenance therapy compared with no treatment after initial treatment with betamethasone valerate in adult patients with AD in Sweden. A further aim was to apply a similar health-economic analysis for Denmark, Norway and Finland. A Markov simulation model was developed including data from three sources: (i) efficacy data from a randomized controlled trial including patients with moderate AD treated with either a moisturizing cream or no treatment, (ii) resource utilization and quality of life data, and (iii) unit prices from official price lists. A societal perspective was used and the analysis was performed according to treatment practice in Sweden. The model simulation was also applied for Denmark, Norway and Finland with inclusion of country-specific unit costs. Sensitivity analyses were performed to test the robustness of the results. The results from the present analyses of treatment for patients with moderate AD indicate that maintenance treatment with a moisturizing cream during eczema-free periods could be cost-effective in a societal perspective. Similar results were obtained for Sweden, Denmark, Norway and Finland. According to the analysis, treatment with a moisturizing cream was found to be a cost-effective option compared with no treatment in eczema-free periods in adult patients with AD in the four Nordic countries.
A Novel Degradation Identification Method for Wind Turbine Pitch System
NASA Astrophysics Data System (ADS)
Guo, Hui-Dong
2018-04-01
It’s difficult for traditional threshold value method to identify degradation of operating equipment accurately. An novel degradation evaluation method suitable for wind turbine condition maintenance strategy implementation was proposed in this paper. Based on the analysis of typical variable-speed pitch-to-feather control principle and monitoring parameters for pitch system, a multi input multi output (MIMO) regression model was applied to pitch system, where wind speed, power generation regarding as input parameters, wheel rotation speed, pitch angle and motor driving currency for three blades as output parameters. Then, the difference between the on-line measurement and the calculated value from the MIMO regression model applying least square support vector machines (LSSVM) method was defined as the Observed Vector of the system. The Gaussian mixture model (GMM) was applied to fitting the distribution of the multi dimension Observed Vectors. Applying the model established, the Degradation Index was calculated using the SCADA data of a wind turbine damaged its pitch bearing retainer and rolling body, which illustrated the feasibility of the provided method.
Game-Theoretic Models for Usage-based Maintenance Contract
NASA Astrophysics Data System (ADS)
Husniah, H.; Wangsaputra, R.; Cakravastia, A.; Iskandar, B. P.
2018-03-01
A usage-based maintenance contracts with coordination and non coordination between two parties is studied in this paper. The contract is applied to a dump truck operated in a mining industry. The situation under study is that an agent offers service contract to the owner of the truck after warranty ends. This contract has only a time limit but no usage limit. If the total usage per period exceeds the maximum usage allowed in the contract, then the owner will be charged an additional cost. In general, the agent (Original Equipment Manufacturer/OEM) provides a full coverage of maintenance, which includes PM and CM under the lease contract. The decision problem for the owner is to select the best option offered that fits to its requirement, and the decision problem for the agent is to find the optimal maintenance efforts for a given price of the service option offered. We first find the optimal decisions using coordination scheme and then with non coordination scheme for both parties.
Preventive maintenance study : interim report.
DOT National Transportation Integrated Search
2017-09-01
This interim report details the performance of 69 test sites treated with various preventive maintenance treatments. The maintenance treatments applied included crack sealing, full lane chip sealing, wheel path chip sealing, dig outs (mill and fill),...
The cost-effectiveness of methadone maintenance as a health care intervention.
Barnett, P G
1999-04-01
Cost-effectiveness analysis using life-years of survival as the measure of treatment benefit is widely used in the economic evaluation of health care interventions but has not been applied to substance abuse treatment. The cost-effectiveness of methadone maintenance was evaluated to demonstrate the feasibility of applying this method to substance abuse treatment. A literature review was undertaken to determine the effect of methadone treatment on the rate of mortality associated with opiate addiction. Information was also obtained on the average cost and duration of treatment. A two-state Markov model was used to estimate the incremental effect of methadone on the life span and treatment cost of a cohort of 25-year-old heroin users. Providing opiate addicts with access to methadone maintenance has an incremental cost-effectiveness ratio of $5915 per life-year gained (that is, for every year of life that is saved by providing methadone to opiate addicts, an additional $5915 in treatment costs are incurred). One-way sensitivity analysis determined that the ratio was less than $10,000 per-life year over a wide range of modeling assumptions. The ratio determined for methadone is lower than that of many common medical therapies, and well within the $50,000 threshold for judging cost-effectiveness. Even if decision makers do not wish use the same ratio that is applied to the general population, this method allows substance abuse treatment enhancements to be compared to improvements in health services offered to individuals with substance abuse disorders. Future work will require information on the impact of methadone treatment on the cost of health care and public programs, the indirect costs incurred by patients, and adjustments to reflect quality of life.
Asphalt in Pavement Maintenance.
ERIC Educational Resources Information Center
Asphalt Inst., College Park, MD.
Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many…
O/S analysis of conceptual space vehicles. Part 1
NASA Technical Reports Server (NTRS)
Ebeling, Charles E.
1995-01-01
The application of recently developed computer models in determining operational capabilities and support requirements during the conceptual design of proposed space systems is discussed. The models used are the reliability and maintainability (R&M) model, the maintenance simulation model, and the operations and support (O&S) cost model. In the process of applying these models, the R&M and O&S cost models were updated. The more significant enhancements include (1) improved R&M equations for the tank subsystems, (2) the ability to allocate schedule maintenance by subsystem, (3) redefined spares calculations, (4) computing a weighted average of the working days and mission days per month, (5) the use of a position manning factor, and (6) the incorporation into the O&S model of new formulas for computing depot and organizational recurring and nonrecurring training costs and documentation costs, and depot support equipment costs. The case study used is based upon a winged, single-stage, vertical-takeoff vehicle (SSV) designed to deliver to the Space Station Freedom (SSF) a 25,000 lb payload including passengers without a crew.
Carnero, María Carmen; Gómez, Andrés
2016-04-23
Healthcare organizations have far greater maintenance needs for their medical equipment than other organization, as many are used directly with patients. However, the literature on asset management in healthcare organizations is very limited. The aim of this research is to provide more rational application of maintenance policies, leading to an increase in quality of care. This article describes a multicriteria decision-making approach which integrates Markov chains with the multicriteria Measuring Attractiveness by a Categorical Based Evaluation Technique (MACBETH), to facilitate the best choice of combination of maintenance policies by using the judgements of a multi-disciplinary decision group. The proposed approach takes into account the level of acceptance that a given alternative would have among professionals. It also takes into account criteria related to cost, quality of care and impact of care cover. This multicriteria approach is applied to four dialysis subsystems: patients infected with hepatitis C, infected with hepatitis B, acute and chronic; in all cases, the maintenance strategy obtained consists of applying corrective and preventive maintenance plus two reserve machines. The added value in decision-making practices from this research comes from: (i) integrating the use of Markov chains to obtain the alternatives to be assessed by a multicriteria methodology; (ii) proposing the use of MACBETH to make rational decisions on asset management in healthcare organizations; (iii) applying the multicriteria approach to select a set or combination of maintenance policies in four dialysis subsystems of a health care organization. In the multicriteria decision making approach proposed, economic criteria have been used, related to the quality of care which is desired for patients (availability), and the acceptance that each alternative would have considering the maintenance and healthcare resources which exist in the organization, with the inclusion of a decision-making group. This approach is better suited to actual health care organization practice and depending on the subsystem analysed, improvements are introduced that are not included in normal maintenance policies; in this way, not only have different maintenance policies been suggested, but also alternatives that, in each case and according to viability, provide a more complete decision tool for the maintenance manager.
Ocean Tide Loading Computation
NASA Technical Reports Server (NTRS)
Agnew, Duncan Carr
2005-01-01
September 15,2003 through May 15,2005 This grant funds the maintenance, updating, and distribution of programs for computing ocean tide loading, to enable the corrections for such loading to be more widely applied in space- geodetic and gravity measurements. These programs, developed under funding from the CDP and DOSE programs, incorporate the most recent global tidal models developed from Topex/Poscidon data, and also local tide models for regions around North America; the design of the algorithm and software makes it straightforward to combine local and global models.
Research on large equipment maintenance system in life cycle
NASA Astrophysics Data System (ADS)
Xu, Xiaowei; Wang, Hongxia; Liu, Zhenxing; Zhang, Nan
2017-06-01
In order to change the current disadvantages of traditional large equipment maintenance concept, this article plans to apply the technical method of prognostics and health management to optimize equipment maintenance strategy and develop large equipment maintenance system. Combined with the maintenance procedures of various phases in life cycle, it concluded the formulation methods of maintenance program and implement plans of maintenance work. In the meantime, it takes account into the example of the dredger power system of the Waterway Bureau to establish the auxiliary platform of ship maintenance system in life cycle.
Architecture for spacecraft operations planning
NASA Technical Reports Server (NTRS)
Davis, William S.
1991-01-01
A system which generates plans for the dynamic environment of space operations is discussed. This system synthesizes plans by combining known operations under a set of physical, functional, and temperal constraints from various plan entities, which are modeled independently but combine in a flexible manner to suit dynamic planning needs. This independence allows the generation of a single plan source which can be compiled and applied to a variety of agents. The architecture blends elements of temperal logic, nonlinear planning, and object oriented constraint modeling to achieve its flexibility. This system was applied to the domain of the Intravehicular Activity (IVA) maintenance and repair aboard Space Station Freedom testbed.
Selecting a preventive maintenance treatment for flexible pavements
DOT National Transportation Integrated Search
2000-06-14
Maintenance engineers have been applying treatments to both flexible and rigid pavements for as long as such pavements have existed. The types and application of various treatments for both corrective and preventive maintenance have been the subject ...
DOT National Transportation Integrated Search
1978-05-01
The Facilities Maintenance Cost Model (FMCM) is an analytic model designed to calculate expected annual labor costs of maintenance within a given FAA maintenance sector. The model is programmed in FORTRAN IV and has been demonstrated on the CDC Krono...
Code of Federal Regulations, 2010 CFR
2010-07-01
... preventative maintenance schedule and, as applicable, detailed descriptions of the corrective action procedures... compliance with the operation and maintenance requirements that apply to me? 63.7826 Section 63.7826... Compliance Requirements § 63.7826 How do I demonstrate initial compliance with the operation and maintenance...
Code of Federal Regulations, 2010 CFR
2010-07-01
... compliance with the operation and maintenance requirements that apply to me? 63.7745 Section 63.7745....7745 How do I demonstrate continuous compliance with the operation and maintenance requirements that... maintenance requirements of § 63.7710 by: (1) Making monthly inspections of capture systems and initiating...
Code of Federal Regulations, 2010 CFR
2010-07-01
... compliance with the operation and maintenance requirements that apply to me? 63.9636 Section 63.9636....9636 How do I demonstrate continuous compliance with the operation and maintenance requirements that... demonstrate continuous compliance with the operation and maintenance requirements in § 63.9600(b) by...
Parenreng, Jumadi Mabe; Kitagawa, Akio
2018-05-17
Wireless Sensor Networks (WSNs) with limited battery, central processing units (CPUs), and memory resources are a widely implemented technology for early warning detection systems. The main advantage of WSNs is their ability to be deployed in areas that are difficult to access by humans. In such areas, regular maintenance may be impossible; therefore, WSN devices must utilize their limited resources to operate for as long as possible, but longer operations require maintenance. One method of maintenance is to apply a resource adaptation policy when a system reaches a critical threshold. This study discusses the application of a security level adaptation model, such as an ARSy Framework, for using resources more efficiently. A single node comprising a Raspberry Pi 3 Model B and a DS18B20 temperature sensor were tested in a laboratory under normal and stressful conditions. The result shows that under normal conditions, the system operates approximately three times longer than under stressful conditions. Maintaining the stability of the resources also enables the security level of a network's data output to stay at a high or medium level.
Kitagawa, Akio
2018-01-01
Wireless Sensor Networks (WSNs) with limited battery, central processing units (CPUs), and memory resources are a widely implemented technology for early warning detection systems. The main advantage of WSNs is their ability to be deployed in areas that are difficult to access by humans. In such areas, regular maintenance may be impossible; therefore, WSN devices must utilize their limited resources to operate for as long as possible, but longer operations require maintenance. One method of maintenance is to apply a resource adaptation policy when a system reaches a critical threshold. This study discusses the application of a security level adaptation model, such as an ARSy Framework, for using resources more efficiently. A single node comprising a Raspberry Pi 3 Model B and a DS18B20 temperature sensor were tested in a laboratory under normal and stressful conditions. The result shows that under normal conditions, the system operates approximately three times longer than under stressful conditions. Maintaining the stability of the resources also enables the security level of a network’s data output to stay at a high or medium level. PMID:29772773
Distributive Effects of Forest Service Attempts to Maintain Community Stability
Steven E. Daniels; William F. Hyde; David N. Wear
1991-01-01
Community stability is an objective of USDA Forest Service timber sales. This paper examines that objective, and the success the Forest Service can have in attaining it, through its intended maintenance of a constant volume timber harvest schedule. We apply a three-factor, two-sector modified general equilibrium model with empirical evidence from the timber-based...
Farajzadegan, Ziba; Fathollahi-Dehkordi, Fariba; Hematti, Simin; Sirous, Reza; Tavakoli, Neda; Rouzbahani, Reza
2016-01-01
Participation of Iranian women with a family history of breast cancer in breast cancer screening programs is low. This study evaluates the compliance of women having a family history of breast cancer with clinical breast exam (CBE) according to the stage of transtheoretical model (TTM) and health belief model (HBM). In this cross-sectional study, we used Persian version of champion's HBM scale to collect factors associated with TTM stages applied to screening from women over 20 years and older. The obtained data were analyzed by SPSS, using descriptive statistics, Chi-square test, independent t -test, and analysis of covariance. Final sample size was 162 women. Thirty-three percent were in action/maintenance stage. Older women, family history of breast cancer in first-degree relatives, personal history of breast disease, insurance coverage, and a history of breast self-examination were associated with action/maintenance stage. Furthermore, women in action/maintenance stages had significantly fewer perceived barriers in terms of CBE in comparison to women in other stages ( P < 0.05). There was no significant difference in other HBM subscales scores between various stages of CBE screening behavior ( P > 0.05). The finding indicates that the rate of women in action/maintenance stage of CBE is low. Moreover, results show a strong association between perceived barriers and having a regular CBE. These clarify the necessity of promoting national target programs for breast cancer screening, which should be considered as the first preference for reducing CBE barriers.
Managing Highway Maintenance: Standards for Maintenance Work, Part 3, Unit 8, Level 2.
ERIC Educational Resources Information Center
Federal Highway Administration (DOT), Washington, DC. Offices of Research and Development.
Part of the series "Managing Highway Maintenance," the unit explains various uses of maintenance standards and how standards should be interpreted and communicated to formen and crew leaders. Several examples are given of the decisions made when applying the standards to routine work. The preceding units on standards (parts 1 and 2)…
Motivation and Self-Regulation in Addiction: A Call for Convergence
Köpetz, Cătălina E.; Lejuez, Carl W.; Wiers, Reinout W.; Kruglanski, Arie W.
2015-01-01
Addiction models have frequently invoked motivational mechanisms to explain the initiation and maintenance of addictive behaviors. However, in doing so, these models have emphasized the unique characteristics of addictive behaviors and overlooked the commonalities that they share with motivated behaviors in general. As a consequence, addiction research has failed to connect with and take advantage of promising and highly relevant advances in motivation and self-regulation research. The present article is a call for a convergence of the previous approaches to addictive behavior and the new advances in basic motivation and self-regulation. The authors emphasize the commonalities that addictive behaviors may share with motivated behavior in general. In addition, it is suggested that the same psychological principles underlying motivated action in general may apply to understand challenging aspects of the etiology and maintenance of addictive behaviors. PMID:26069472
Perceived autonomy support, friendship maintenance, and happiness.
Demir, Melikşah; Ozdemir, Metin; Marum, Kendra Patrice
2011-01-01
Decades of empirical research have shown that perceived autonomy support in close relationships is an essential correlate of happiness. However, what might account for the relationship between the 2? For this article, 4 studies (total N=1325) investigated friendship maintenance as a mediator of the association between friendship autonomy support and happiness. The first 3 studies supported the model for the best friendship of the individual when happiness was assessed with 3 different measures. The 4th study extended the findings by showing that the model was generalizable to the other close friendship of the individual. Overall, the results supported the idea that engaging in routine and strategic behaviors to maintain friendships explains how perceived autonomy support in friendships is associated with happiness. The theoretical and applied implications of the findings were discussed and suggestions for future research were made.
Code of Federal Regulations, 2013 CFR
2013-07-01
... unscheduled data on magnetic records storage media onto tested and verified new electronic media. ... apply to the selection and maintenance of electronic records storage media for permanent records? Â... storage media for permanent records? (a) Agencies must maintain the storage and test areas for electronic...
Research requirements to reduce maintenance costs of civil helicopters
NASA Technical Reports Server (NTRS)
Million, D. J.; Waters, K. T.
1978-01-01
The maintenance problems faced by the operators of civil helicopters that result in high costs are documented. Existing technology that can be applied to reduce maintenance costs and research that should be carried out were identified. Good design practice and application of existing technology were described as having a significant impact on reducing maintenance costs immediately. The research and development that have potential for long range reduction of maintenance costs are presented.
Applying Lean to the AC-130 Maintenance Process for the Royal Saudi Air Force
2016-09-01
inventory management. Quality Management Poor quality of maintenance contributes to rework , which is an obvious form of waste. It would be very...consequences of rework are very significant. Within the C-130 maintenance squadron, quality must be achieved through continual process improvements, rather...maintenance “product” quality by lowering measurable process outputs such as amount of rework , number of maintenance-induced failures, and so on. 71
Maintenance Training Simulator Design and Acquisition.
1980-08-01
7 ADA69 149 APPLIED SCIENCE ASSOCIATES INC VALENCIA PA F/6 5/9 MAINTENANCE TRAINING SIMULATOR DESIG AND ACOUISITION.(U) AUG 8O R J HRITZ. 6 R...TRAINING SIMULATOR DESIGN H AND ACQUISIIONII By Rohn J. Htz George R. Purifoy, Jr. M Applied Science Associates, Inc. Box 158A Valencia , Pennsylvania...related thereto. This report was submitted by Applied Science Associates, Inc., Box 158. Valencia . Pennsyvania 10059. under Contract F33015-78-C-409
76 FR 9513 - Airworthiness Directives; BURKHART GROB LUFT-UND Model G 103 C Twin III SL Gliders
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-18
... plate) and tighten it, applying the torque following page 6.12 of the G 103 C TWIN III SL Maintenance...: The torque values and tolerances of the upper pulley wheel grooved nut have been standardized in the..., before further flight, readjust the torque of the upper pulley wheel grooved nut using the updated...
Massah, Omid; Sohrabi, Faramarz; A'azami, Yousef; Doostian, Younes; Farhoudian, Ali; Daneshmand, Reza
2016-03-01
Emotion plays an important role in adapting to life changes and stressful events. Difficulty regulating emotions is one of the problems drug abusers often face, and teaching these individuals to express and manage their emotions can be effective on improving their difficult circumstances. The present study aimed to determine the effectiveness of the Gross model-based emotion regulation strategies training on anger reduction in drug-dependent individuals. The present study had a quasi-experimental design wherein pretest-posttest evaluations were applied using a control group. The population under study included addicts attending Marivan's methadone maintenance therapy centers in 2012 - 2013. Convenience sampling was used to select 30 substance-dependent individuals undergoing maintenance treatment who were then randomly assigned to the experiment and control groups. The experiment group received its training in eight two-hour sessions. Data were analyzed using analysis of co-variance and paired t-test. There was significant reduction in anger symptoms of drug-dependent individuals after gross model based emotion regulation training (ERT) (P < 0.001). Moreover, the effectiveness of the training on anger was persistent in the follow-up period. Symptoms of anger in drug-dependent individuals of this study were reduced by gross model-based emotion regulation strategies training. Based on the results of this study, we may conclude that the gross model based emotion regulation strategies training can be applied alongside other therapies to treat drug abusers undergoing rehabilitation.
Iwai, Sosuke; Fujiwara, Kenji; Tamura, Takuro
2016-09-01
Algal endosymbiosis is widely distributed in eukaryotes including many protists and metazoans, and plays important roles in aquatic ecosystems, combining phagotrophy and phototrophy. To maintain a stable symbiotic relationship, endosymbiont population size in the host must be properly regulated and maintained at a constant level; however, the mechanisms underlying the maintenance of algal endosymbionts are still largely unknown. Here we investigate the population dynamics of the unicellular ciliate Paramecium bursaria and its Chlorella-like algal endosymbiont under various experimental conditions in a simple culture system. Our results suggest that endosymbiont population size in P. bursaria was not regulated by active processes such as cell division coupling between the two organisms, or partitioning of the endosymbionts at host cell division. Regardless, endosymbiont population size was eventually adjusted to a nearly constant level once cells were grown with light and nutrients. To explain this apparent regulation of population size, we propose a simple mechanism based on the different growth properties (specifically the nutrient requirements) of the two organisms, and based from this develop a mathematical model to describe the population dynamics of host and endosymbiont. The proposed mechanism and model may provide a basis for understanding the maintenance of algal endosymbionts. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.
Hattar, Anne; Pal, Sebely; Hagger, Martin S
2016-03-01
We tested the adequacy of a model based on the Health Action Process Approach (HAPA) in predicting changes in psychological, body composition, and cardiovascular risk outcomes with respect to physical activity participation in overweight and obese adults. Measures of HAPA constructs (action and maintenance self-efficacy, outcome expectancies, action planning, risk perceptions, intentions, behaviour), psychological outcomes (quality of life, depression, anxiety, stress symptoms), body composition variables (body weight, body fat mass), cardiovascular risk measures (total cholesterol, low density lipoprotein), and self-reported physical activity behaviour were administered to participants (N = 74) at baseline, and 6 and 12 weeks later. Data were analysed using variance-based structural equation modelling with residualised change scores for HAPA variables. The model revealed effects of action self-efficacy and outcome expectancies on physical activity intentions, action self-efficacy on maintenance self-efficacy, and maintenance self-efficacy and intentions on action planning. Intention predicted psychological and body composition outcomes indirectly through physical activity behaviour. Action planning was a direct predictor of psychological, cardiovascular, and body composition outcomes. Data supported HAPA hypotheses in relation to intentions and behaviour, but not the role of action planning as a mediator of the intention-behaviour relationship. Action planning predicted outcomes independent of intentions and behaviour. © 2016 The International Association of Applied Psychology.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Continuous... maintenance requirements that apply to me? (a) For each by-product coke oven battery, you must demonstrate... each coke oven battery with a capture system or control device applied to pushing emissions, you must...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Continuous... maintenance requirements that apply to me? (a) For each by-product coke oven battery, you must demonstrate... each coke oven battery with a capture system or control device applied to pushing emissions, you must...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Continuous... maintenance requirements that apply to me? (a) For each by-product coke oven battery, you must demonstrate... each coke oven battery with a capture system or control device applied to pushing emissions, you must...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Continuous... maintenance requirements that apply to me? (a) For each by-product coke oven battery, you must demonstrate... each coke oven battery with a capture system or control device applied to pushing emissions, you must...
Code of Federal Regulations, 2013 CFR
2013-07-01
... Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks Continuous... maintenance requirements that apply to me? (a) For each by-product coke oven battery, you must demonstrate... each coke oven battery with a capture system or control device applied to pushing emissions, you must...
A probabilistic maintenance model for diesel engines
NASA Astrophysics Data System (ADS)
Pathirana, Shan; Abeygunawardane, Saranga Kumudu
2018-02-01
In this paper, a probabilistic maintenance model is developed for inspection based preventive maintenance of diesel engines based on the practical model concepts discussed in the literature. Developed model is solved using real data obtained from inspection and maintenance histories of diesel engines and experts' views. Reliability indices and costs were calculated for the present maintenance policy of diesel engines. A sensitivity analysis is conducted to observe the effect of inspection based preventive maintenance on the life cycle cost of diesel engines.
40 CFR 93.102 - Applicability.
Code of Federal Regulations, 2010 CFR
2010-07-01
... PM2.5 nonattainment and maintenance areas with respect to PM2.5 from re-entrained road dust if the EPA... further progress, attainment or maintenance strategy. Re-entrained road dust emissions are produced by... applicability. The provisions of this subpart shall apply in all nonattainment and maintenance areas for...
Optimizing preventive maintenance policy: A data-driven application for a light rail braking system.
Corman, Francesco; Kraijema, Sander; Godjevac, Milinko; Lodewijks, Gabriel
2017-10-01
This article presents a case study determining the optimal preventive maintenance policy for a light rail rolling stock system in terms of reliability, availability, and maintenance costs. The maintenance policy defines one of the three predefined preventive maintenance actions at fixed time-based intervals for each of the subsystems of the braking system. Based on work, maintenance, and failure data, we model the reliability degradation of the system and its subsystems under the current maintenance policy by a Weibull distribution. We then analytically determine the relation between reliability, availability, and maintenance costs. We validate the model against recorded reliability and availability and get further insights by a dedicated sensitivity analysis. The model is then used in a sequential optimization framework determining preventive maintenance intervals to improve on the key performance indicators. We show the potential of data-driven modelling to determine optimal maintenance policy: same system availability and reliability can be achieved with 30% maintenance cost reduction, by prolonging the intervals and re-grouping maintenance actions.
Optimizing preventive maintenance policy: A data-driven application for a light rail braking system
Corman, Francesco; Kraijema, Sander; Godjevac, Milinko; Lodewijks, Gabriel
2017-01-01
This article presents a case study determining the optimal preventive maintenance policy for a light rail rolling stock system in terms of reliability, availability, and maintenance costs. The maintenance policy defines one of the three predefined preventive maintenance actions at fixed time-based intervals for each of the subsystems of the braking system. Based on work, maintenance, and failure data, we model the reliability degradation of the system and its subsystems under the current maintenance policy by a Weibull distribution. We then analytically determine the relation between reliability, availability, and maintenance costs. We validate the model against recorded reliability and availability and get further insights by a dedicated sensitivity analysis. The model is then used in a sequential optimization framework determining preventive maintenance intervals to improve on the key performance indicators. We show the potential of data-driven modelling to determine optimal maintenance policy: same system availability and reliability can be achieved with 30% maintenance cost reduction, by prolonging the intervals and re-grouping maintenance actions. PMID:29278245
Kang, Xiaofeng; Dennison Himmelfarb, Cheryl R; Li, Zheng; Zhang, Jian; Lv, Rong; Guo, Jinyu
2015-01-01
The Self-care of Heart Failure Index (SCHFI) is an empirically tested instrument for measuring the self-care of patients with heart failure. The aim of this study was to develop a simplified Chinese version of the SCHFI and provide evidence for its construct validity. A total of 182 Chinese with heart failure were surveyed. A 2-step structural equation modeling procedure was applied to test construct validity. Factor analysis showed 3 factors explaining 43% of the variance. Structural equation model confirmed that self-care maintenance, self-care management, and self-care confidence are indeed indicators of self-care, and self-care confidence was a positive and equally strong predictor of self-care maintenance and self-care management. Moreover, self-care scores were correlated with the Partners in Health Scale, indicating satisfactory concurrent validity. The Chinese version of the SCHFI is a theory-based instrument for assessing self-care of Chinese patients with heart failure.
An application of the transtheoretical model to becoming vegan.
Mendes, Elisabeth
2013-01-01
This article applies the transtheoretical model TM to veganism. By and large, the TM is a model of behavioral change that incorporates different stages to describe how an individual moves from an unhealthy behavior to a healthy one. The TM construes change as a five-stage process. The five stages of change are (a) precontemplation, (b) contemplation, (c) preparation, (d) action, and (e) maintenance. In this analysis, the model is applied to a person's determination to become vegan. A person chooses to become a vegan by eliminating all animal products from his or her diets; he or she does this by progressing through the stages, as prescribed by the model. The different changes people make to their life are described in detail. It is also possible to measure the success of a person's progression based on positive health changes that he or she experiences.
Performance-based maintenance of gas turbines for reliable control of degraded power systems
NASA Astrophysics Data System (ADS)
Mo, Huadong; Sansavini, Giovanni; Xie, Min
2018-03-01
Maintenance actions are necessary for ensuring proper operations of control systems under component degradation. However, current condition-based maintenance (CBM) models based on component health indices are not suitable for degraded control systems. Indeed, failures of control systems are only determined by the controller outputs, and the feedback mechanism compensates the control performance loss caused by the component deterioration. Thus, control systems may still operate normally even if the component health indices exceed failure thresholds. This work investigates the CBM model of control systems and employs the reduced control performance as a direct degradation measure for deciding maintenance activities. The reduced control performance depends on the underlying component degradation modelled as a Wiener process and the feedback mechanism. To this aim, the controller features are quantified by developing a dynamic and stochastic control block diagram-based simulation model, consisting of the degraded components and the control mechanism. At each inspection, the system receives a maintenance action if the control performance deterioration exceeds its preventive-maintenance or failure thresholds. Inspired by realistic cases, the component degradation model considers random start time and unit-to-unit variability. The cost analysis of maintenance model is conducted via Monte Carlo simulation. Optimal maintenance strategies are investigated to minimize the expected maintenance costs, which is a direct consequence of the control performance. The proposed framework is able to design preventive maintenance actions on a gas power plant, to ensuring required load frequency control performance against a sudden load increase. The optimization results identify the trade-off between system downtime and maintenance costs as a function of preventive maintenance thresholds and inspection frequency. Finally, the control performance-based maintenance model can reduce maintenance costs as compared to CBM and pre-scheduled maintenance.
2015-09-01
15 4. Commander, Naval Regional Maintenance Center .................. 15 5 . Private Ship Repair Industry...TURBINE EXHAUST SYSTEM MAINTENANCE STRATEGY FOR THE CG-47 TICONDEROGA CLASS CRUISER 5 . FUNDING NUMBERS 6. AUTHOR(S) Sparks, Robert D. 7. PERFORMING...condition-based maintenance, condition-directed, failure finding, fault tree analysis 15 . NUMBER OF PAGES 133 16. PRICE CODE 17. SECURITY
ERIC Educational Resources Information Center
Livermore, Craig
2008-01-01
Much has been written about the adaptation from criminology of the "Broken Windows" theory of order maintenance in successful urban educational models. Yet, the manner in which the theory is written and discussed often misses the nuances and feel of the theory as successfully applied. This misunderstanding has lead to its conflation with the "Zero…
Liu, Li; Liu, Yue-Ping; Wang, Jing; An, Li-Wei; Jiao, Jian-Mei
2016-06-01
To investigate the effects of a knowledge-attitude-behaviour health education model on acquisition of disease-related knowledge and self-management behaviour by patients undergoing maintenance haemodialysis. Patients recently prescribed MHD were randomly assigned to a control group or an intervention group. Control group patients were treated with usual care and general education models. A specialist knowledge-attitude-behaviour health education model was applied to patients in the intervention group. Eighty-six patients were included (n = 43 per group). Before intervention, there were no significant between-group differences in disease knowledge and self-management behaviour. After 6 months' intervention, a significant between-group difference in acquisition of disease knowledge was observed. Self-management behaviour scores (control of body mass, reasonable diet, correct drug intake, physical activity, correct fistula care, disease condition monitoring, psychological and social behaviours) for the intervention group were also higher than those for the control group. These preliminary findings suggest that the knowledge-attitude-behaviour model appears to be a valuable tool for the health education of MHD patients. © The Author(s) 2016.
Liu, Li; Wang, Jing; An, Li-Wei; Jiao, Jian-Mei
2016-01-01
Objective To investigate the effects of a knowledge-attitude-behaviour health education model on acquisition of disease-related knowledge and self-management behaviour by patients undergoing maintenance haemodialysis. Methods Patients recently prescribed MHD were randomly assigned to a control group or an intervention group. Control group patients were treated with usual care and general education models. A specialist knowledge-attitude-behaviour health education model was applied to patients in the intervention group. Results Eighty-six patients were included (n = 43 per group). Before intervention, there were no significant between-group differences in disease knowledge and self-management behaviour. After 6 months’ intervention, a significant between-group difference in acquisition of disease knowledge was observed. Self-management behaviour scores (control of body mass, reasonable diet, correct drug intake, physical activity, correct fistula care, disease condition monitoring, psychological and social behaviours) for the intervention group were also higher than those for the control group. Conclusion These preliminary findings suggest that the knowledge-attitude-behaviour model appears to be a valuable tool for the health education of MHD patients. PMID:26951842
78 FR 282 - Submission for OMB Review; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-03
... maintenance levels. Level one includes roads, which are closed and maintained only to protect the environment... commercial users to apply and pay for a permit to use the FS Road System. Maintenance resulting from...-41 or FS-7700-48, to identify the road maintenance that is the direct result of the applicant's...
40 CFR 1054.145 - Are there interim provisions that apply only for a limited time?
Code of Federal Regulations, 2010 CFR
2010-07-01
... scheduled emission-related maintenance falls within 10 hours of a test point, delay the maintenance until the engine reaches the test point. Measure emissions before and after peforming the maintenance. Use... example, for the fuel line permeation standards starting in 2012, equipment manufacturers may order a...
Modeling a maintenance simulation of the geosynchronous platform
NASA Technical Reports Server (NTRS)
Kleiner, A. F., Jr.
1980-01-01
A modeling technique used to conduct a simulation study comparing various maintenance routines for a space platform is dicussed. A system model is described and illustrated, the basic concepts of a simulation pass are detailed, and sections on failures and maintenance are included. The operation of the system across time is best modeled by a discrete event approach with two basic events - failure and maintenance of the system. Each overall simulation run consists of introducing a particular model of the physical system, together with a maintenance policy, demand function, and mission lifetime. The system is then run through many passes, each pass corresponding to one mission and the model is re-initialized before each pass. Statistics are compiled at the end of each pass and after the last pass a report is printed. Items of interest typically include the time to first maintenance, total number of maintenance trips for each pass, average capability of the system, etc.
Maintenance of the Hanford cone penetrometer platform during fiscal year 1999
DOE Office of Scientific and Technical Information (OSTI.GOV)
IWATATE, D.F.
This SOW describes services requested of Applied Research and Associates, Inc. (ARA), as a commercial provider of cone penetrometer equipment and services, to provide routine inspection and minimum preventive maintenance on the Hanford CP Platform (CPP) during Fiscal Year 1999. This SOW specifically pertains to the maintenance of the CPP and associated support equipment and is limited in scope to routine preventive maintenance and identification of any deficiencies. ARA is the original manufacturer of the CPP and will conduct this work following the vendor-prepared maintenance schedule.
Massah, Omid; Sohrabi, Faramarz; A’azami, Yousef; Doostian, Younes; Farhoudian, Ali; Daneshmand, Reza
2016-01-01
Background Emotion plays an important role in adapting to life changes and stressful events. Difficulty regulating emotions is one of the problems drug abusers often face, and teaching these individuals to express and manage their emotions can be effective on improving their difficult circumstances. Objectives The present study aimed to determine the effectiveness of the Gross model-based emotion regulation strategies training on anger reduction in drug-dependent individuals. Patients and Methods The present study had a quasi-experimental design wherein pretest-posttest evaluations were applied using a control group. The population under study included addicts attending Marivan’s methadone maintenance therapy centers in 2012 - 2013. Convenience sampling was used to select 30 substance-dependent individuals undergoing maintenance treatment who were then randomly assigned to the experiment and control groups. The experiment group received its training in eight two-hour sessions. Data were analyzed using analysis of co-variance and paired t-test. Results There was significant reduction in anger symptoms of drug-dependent individuals after gross model based emotion regulation training (ERT) (P < 0.001). Moreover, the effectiveness of the training on anger was persistent in the follow-up period. Conclusions Symptoms of anger in drug-dependent individuals of this study were reduced by gross model-based emotion regulation strategies training. Based on the results of this study, we may conclude that the gross model based emotion regulation strategies training can be applied alongside other therapies to treat drug abusers undergoing rehabilitation. PMID:27162759
NASA Astrophysics Data System (ADS)
Sharaunga, S.; Mudhara, M.
2018-06-01
The decentralization framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasize the need for a participatory approach to irrigation water management. This study identifies the factors influencing farmers' decision to, and extent of participation in the maintenance of irrigation infrastructure in KwaZulu-Natal province, South Africa based on cross-section data collected from 320 randomly selected smallholder irrigating farmers. A two-step Heckman regression model was applied in the analysis. It was established that households whose heads were older, block committee members, with larger irrigation plots, good soil quality and experiencing severe irrigation water shortages are more likely to participate in maintenance of irrigation infrastructure. On the other hand, farmers with insecure land tenure and with no access to irrigation water were less likely to make the decision to participate. Farmers who were members of the farming cooperative as well as block committee members and those paying irrigation water costs were likely to intensively participate in maintaining irrigation infrastructure. Therefore, decentralization alone cannot lead to improved irrigation outcomes. Several factors are necessary for households to participate intensively in the maintenance of irrigation infrastructure. Governments should address these challenges before handing irrigation schemes to their beneficiaries.
30 CFR 75.403 - Maintenance of incombustible content of rock dust.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Maintenance of incombustible content of rock... Materials and Rock Dusting § 75.403 Maintenance of incombustible content of rock dust. [Statutory Provision] Where rock dust is required to be applied, it shall be distributed upon the top, floor, and sides of all...
40 CFR 1054.145 - Are there interim provisions that apply only for a limited time?
Code of Federal Regulations, 2011 CFR
2011-07-01
... scheduled emission-related maintenance falls within 10 hours of a test point, delay the maintenance until the engine reaches the test point. Measure emissions before and after peforming the maintenance. Use... data under 40 CFR 1060.235(e) for your emission family. (j) Continued use of 40 CFR part 90 test...
40 CFR 1054.145 - Are there interim provisions that apply only for a limited time?
Code of Federal Regulations, 2012 CFR
2012-07-01
... scheduled emission-related maintenance falls within 10 hours of a test point, delay the maintenance until the engine reaches the test point. Measure emissions before and after peforming the maintenance. Use... data under 40 CFR 1060.235(e) for your emission family. (j) Continued use of 40 CFR part 90 test...
Space shuttle recommendations based on aircraft maintenance experience
NASA Technical Reports Server (NTRS)
Spears, J. M.; Fox, C. L.
1972-01-01
Space shuttle design recommendations based on aircraft maintenance experience are developed. The recommendations are specifically applied to the landing gear system, nondestructive inspection techniques, hydraulic system design, materials and processes, and program support.
Neurocognitive systems related to real-world prospective memory.
Kalpouzos, Grégoria; Eriksson, Johan; Sjölie, Daniel; Molin, Jonas; Nyberg, Lars
2010-10-08
Prospective memory (PM) denotes the ability to remember to perform actions in the future. It has been argued that standard laboratory paradigms fail to capture core aspects of PM. We combined functional MRI, virtual reality, eye-tracking and verbal reports to explore the dynamic allocation of neurocognitive processes during a naturalistic PM task where individuals performed errands in a realistic model of their residential town. Based on eye movement data and verbal reports, we modeled PM as an iterative loop of five sustained and transient phases: intention maintenance before target detection (TD), TD, intention maintenance after TD, action, and switching, the latter representing the activation of a new intention in mind. The fMRI analyses revealed continuous engagement of a top-down fronto-parietal network throughout the entire task, likely subserving goal maintenance in mind. In addition, a shift was observed from a perceptual (occipital) system while searching for places to go, to a mnemonic (temporo-parietal, fronto-hippocampal) system for remembering what actions to perform after TD. Updating of the top-down fronto-parietal network occurred at both TD and switching, the latter likely also being characterized by frontopolar activity. Taken together, these findings show how brain systems complementary interact during real-world PM, and support a more complete model of PM that can be applied to naturalistic PM tasks and that we named PROspective MEmory DYnamic (PROMEDY) model because of its dynamics on both multi-phase iteration and the interactions of distinct neurocognitive networks.
2012-12-01
and activity coordination (for example, SOC management ). 10. In Reference D the information sharing framework represents a hub & node model in... management , vulnerabilities, critical assets, threats, impacts on operations etc. UNCLASSIFIED UNCLASSIFIED 6 PART 3 - CYBER SITUATIONAL AWARENESS...limit the effect of cyber incidents. 23. Tasks of the SOC include: • System maintenance and management including applying the directed security
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain; ...
2017-09-23
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
A Theoretical Reassessment of Microbial Maintenance and Implications for Microbial Ecology Modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Gangsheng; Post, Wilfred M
We attempted to reconcile three microbial maintenance models (Herbert, Pirt, and Compromise) through a critical reassessment. We provided a rigorous proof that the true growth yield coefficient (YG) is the ratio of the specific maintenance rate (a in Herbert) to the maintenance coefficient (m in Pirt). Other findings from this study include: (1) the Compromise model is identical to the Herbert for computing microbial growth and substrate consumption, but it expresses the dependence of maintenance on both microbial biomass and substrate; (2) the maximum specific growth rate in the Herbert ( max,H) is higher than those in the other twomore » models ( max,P and max,C), and the difference is the physiological maintenance factor (mq = a); and (3) the overall maintenance coefficient (mT) is more sensitive to mq than to the specific growth rate ( G) and YG. Our critical reassessment of microbial maintenance provides a new approach for quantifying some important components in soil microbial ecology models.« less
Sezdi, Mana
2016-01-01
A maintenance program generated through the consideration of characteristics and failures of medical equipment is an important component of technology management. However, older technology devices and newer high-tech devices cannot be efficiently managed using the same strategies because of their different characteristics. This study aimed to generate a maintenance program comprising two different strategies to increase the efficiency of device management: preventive maintenance for older technology devices and predictive maintenance for newer high-tech devices. For preventive maintenance development, 589 older technology devices were subjected to performance verification and safety testing (PVST). For predictive maintenance development, the manufacturers' recommendations were used for 134 high-tech devices. These strategies were evaluated in terms of device reliability. This study recommends the use of two different maintenance strategies for old and new devices at hospitals in developing countries. Thus, older technology devices that applied only corrective maintenance will be included in maintenance like high-tech devices.
Sezdi, Mana
2016-01-01
A maintenance program generated through the consideration of characteristics and failures of medical equipment is an important component of technology management. However, older technology devices and newer high-tech devices cannot be efficiently managed using the same strategies because of their different characteristics. This study aimed to generate a maintenance program comprising two different strategies to increase the efficiency of device management: preventive maintenance for older technology devices and predictive maintenance for newer high-tech devices. For preventive maintenance development, 589 older technology devices were subjected to performance verification and safety testing (PVST). For predictive maintenance development, the manufacturers' recommendations were used for 134 high-tech devices. These strategies were evaluated in terms of device reliability. This study recommends the use of two different maintenance strategies for old and new devices at hospitals in developing countries. Thus, older technology devices that applied only corrective maintenance will be included in maintenance like high-tech devices. PMID:27195666
Economic Evaluation of Advanced Winter Highway Maintenance Strategies
DOT National Transportation Integrated Search
1998-01-01
Highway agencies face demands to maintain or improve the existing winter roadway level of service. This paper examines the potential benefits of applying advanced winter highway maintenance strategies. The Vermont Agency of Transportation conducted "...
Boelter, Fred W; Xia, Yulin; Persky, Jacob D
2017-09-01
Assessing exposures to hazards in order to characterize risk is at the core of occupational hygiene. Our study examined dropped ceiling systems commonly used in schools and commercial buildings and lay-in ceiling panels that may have contained asbestos prior to the mid to late 1970s. However, most ceiling panels and tiles do not contain asbestos. Since asbestos risk relates to dose, we estimated the distribution of eight-hour TWA concentrations and one-year exposures (a one-year dose equivalent) to asbestos fibers (asbestos f/cc-years) for five groups of workers who may encounter dropped ceilings: specialists, generalists, maintenance workers, nonprofessional do-it-yourself (DIY) persons, and other tradespersons who are bystanders to ceiling work. Concentration data (asbestos f/cc) were obtained through two exposure assessment studies in the field and one chamber study. Bayesian and stochastic models were applied to estimate distributions of eight-hour TWAs and annual exposures (dose). The eight-hour TWAs for all work categories were below current and historic occupational exposure limits (OELs). Exposures to asbestos fibers from dropped ceiling work would be categorized as "highly controlled" for maintenance workers and "well controlled" for remaining work categories, according to the American Industrial Hygiene Association exposure control rating system. Annual exposures (dose) were found to be greatest for specialists, followed by maintenance workers, generalists, bystanders, and DIY. On a comparative basis, modeled dose and thus risk from dropped ceilings for all work categories were orders of magnitude lower than published exposures for other sources of banned friable asbestos-containing building material commonly encountered in construction trades. © 2016 The Authors Risk Analysis published by Wiley Periodicals, Inc. on behalf of Society for Risk Analysis.
Cammarota, M; Huppes, V; Gaia, S; Degoulet, P
1998-01-01
The development of Health Information Systems is widely determined by the establishment of the underlying information models. An Object-Oriented Matrix Model (OOMM) is described which target is to facilitate the integration of the overall health system. The model is based on information modules named micro-databases that are structured in a three-dimensional network: planning, health structures and information systems. The modelling tool has been developed as a layer on top of a relational database system. A visual browser facilitates the development and maintenance of the information model. The modelling approach has been applied to the Brasilia University Hospital since 1991. The extension of the modelling approach to the Brasilia regional health system is considered.
Analysis of EA-18G Growler Engine Maintenance at Naval Air Station Whidbey Island, WA
2013-06-01
maintenance. A. NAVAL AVIATION MAINTENANCE PROGRAM The aviation maintenance community considers the NAMP its bible . “The NAMP applies to all...will increase to 114, which is the total number of aircraft at the completion of the acquisition process in year 2018 (increasing by 12 per year...until 2018 where eight will complete the acquisition) The cost of the F414-GE-400 engine is about 3.7 million dollars. B. CALCULATING THE ENGINE Aₒ
Applying Lean to the F-15 Maintenance Process for the Royal Saudi Air Force
2014-03-01
Royal Saudi Air Force. The research focuses on improving the F-15 maintenance process in the Royal Saudi Air Force’s Maintenance Squadrons. The F-15...and on the aircraft age condition, the researcher concludes it is time to get rid of some obstacles and use new management techniques to resolve the...processes? Research Focus This research is focusing on the Royal Saudi Air Force F-15 maintenance process. Because of the time and
Economic Evaluation of Advanced Winter Highway Maintenance Strategies
DOT National Transportation Integrated Search
1988-01-01
Highway agencies face demands to maintain or improve the existing winter roadway level of service. The benefits of advanced winter highway maintenance strategies now become more attractive. This paper examines the potential benefits of applying advan...
Economic evaluation of advanced winter highway maintenance strategies
DOT National Transportation Integrated Search
1998-08-19
Highway agencies face demands to maintain or improve the existing winter roadway level of service. The benefits of advanced winter highway maintenance strategies now become more attractive. This paper examines the potential benefits of applying advan...
A theoretical reassessment of microbial maintenance and implications for microbial ecology modeling.
Wang, Gangsheng; Post, Wilfred M
2012-09-01
We attempted to reconcile three microbial maintenance models (Herbert, Pirt, and Compromise) through a theoretical reassessment. We provided a rigorous proof that the true growth yield coefficient (Y(G)) is the ratio of the specific maintenance rate (a in Herbert) to the maintenance coefficient (m in Pirt). Other findings from this study include: (1) the Compromise model is identical to the Herbert for computing microbial growth and substrate consumption, but it expresses the dependence of maintenance on both microbial biomass and substrate; (2) the maximum specific growth rate in the Herbert (μ(max,H)) is higher than those in the other two models (μ(max,P) and μ(max,C)), and the difference is the physiological maintenance factor (m(q) = a); and (3) the overall maintenance coefficient (m(T)) is more sensitive to m(q) than to the specific growth rate (μ(G)) and Y(G). Our critical reassessment of microbial maintenance provides a new approach for quantifying some important components in soil microbial ecology models. © This article is a US government work and is in the public domain in the USA.
Geomorphological hazard and tourist vulnerability along Portofino Park trails (Italy)
NASA Astrophysics Data System (ADS)
Brandolini, P.; Faccini, F.; Piccazzo, M.
2006-06-01
The many trails existing in the coastal area of Portofino Promontory are used by tourists for trekking or as pathways to small villages and beaches. The aim of this paper is to define geomorphological hazard and tourist vulnerability in this area, within the framework of the management and planning of hiking activities in Portofino Natural Park. In particular, processes triggered by gravity, running waters and wave motion, affecting the slopes and the cliff, are considered. The typology of the trails and trail maintenance are also taken into account in relation to weather conditions that can make the excursion routes dangerous for tourists. In conclusion, an operative model is applied for the definition of possible risk scenarios. This model is founded on an inventory and the quantification of geomorphological hazards and tourist vulnerability, in comparison with trail rescue data. The model can be applied to other environments and tourist areas.
Projection of Maximum Software Maintenance Manning Levels.
1982-06-01
mainte- nance team development and for outyear support resource estimation, and to provide an analysis of applications of the model in areas other...by General Research Corporation of Santa Barbara, Ca., indicated that the Planning and Resource Management Information System (PARRIS) at the Air Force...determined that when the optimal input effort is applied, steps in the development would be achieved at a rate proportional to V(t). Thus the work-rate could
A Study on Predictive Analytics Application to Ship Machinery Maintenance
2013-09-01
Looking at the nature of the time series forecasting method , it would be better applied to offline analysis . The application for real- time online...other system attributes in future. Two techniques of statistical analysis , mainly time series models and cumulative sum control charts, are discussed in...statistical tool employed for the two techniques of statistical analysis . Both time series forecasting as well as CUSUM control charts are shown to be
A particle swarm model for estimating reliability and scheduling system maintenance
NASA Astrophysics Data System (ADS)
Puzis, Rami; Shirtz, Dov; Elovici, Yuval
2016-05-01
Modifying data and information system components may introduce new errors and deteriorate the reliability of the system. Reliability can be efficiently regained with reliability centred maintenance, which requires reliability estimation for maintenance scheduling. A variant of the particle swarm model is used to estimate reliability of systems implemented according to the model view controller paradigm. Simulations based on data collected from an online system of a large financial institute are used to compare three component-level maintenance policies. Results show that appropriately scheduled component-level maintenance greatly reduces the cost of upholding an acceptable level of reliability by reducing the need in system-wide maintenance.
Improving software maintenance through measurement
NASA Technical Reports Server (NTRS)
Rombach, H. Dieter; Ulery, Bradford T.
1989-01-01
A practical approach to improving software maintenance through measurements is presented. This approach is based on general models for measurement and improvement. Both models, their integration, and practical guidelines for transferring them into industrial maintenance settings are presented. Several examples of applications of the approach to real-world maintenance environments are discussed.
Evaluation of artillery equipment maintenance support capability based on grey clustering
NASA Astrophysics Data System (ADS)
Zhai, Mei-jie; Gao, Peng
2017-12-01
This paper, the theory and method of evaluating the capability of equipment maintenance support in China and abroad are studied, from the point of view of the combat task of artillery troops and the strategic attachment in the future military struggle. This paper establishes the framework of the evaluation Index system of the equipment maintenance support capability of the artillery units, and applies the grey clustering method to the evaluation of the equipment maintenance support capability of the artillery units, and finally evaluates the equipment maintenance and support capability of the artillery brigade as an example, and analyzes the evaluation results. This paper finds out the outstanding problems existing in the maintenance and support of military equipment, and puts forward some constructive suggestions, in order to improve the status of military equipment maintenance and support and improve the level of future equipment maintenance.
What maintains the waters flowing in our rivers?
NASA Astrophysics Data System (ADS)
Vasconcelos, Vitor Vieira
2017-07-01
This article discusses how new contributions from hydrogeological science in the 20th and 21st centuries have allowed for a better understanding of the processes that affect the maintenance of river flows. Moreover, the way in which this knowledge has been conveyed beyond academia and has been gradually incorporated into public policy for natural resource management is also discussed. This article explains the development of several approaches used to understand the relationships among the management of aquifers, vegetation and river flows, including water balance, aquifer recharge, the piston effect, seasonal effects, and safe and sustainable yields. Additionally, the current challenges regarding the modeling of hydrological processes that integrate groundwater and surface waters are discussed. Examples of studies applied in Brazil that demonstrate these processes and stimulate thought regarding water management strategies are presented. In light of the case studies, it is possible to propose different strategies, each adapted for specific hydrogeological context to maximize aquifer recharge or base flow maintenance. Based on these strategies, the role of infiltration ponds and other artificial recharge techniques is re-evaluated in the context of the mitigation of environmental impacts on the maintenance of river flows. Proposals for the improvement of public policies regarding the payment of related environmental services to stimulate investment in aquifer recharge and the maintenance of base flow, for which the goal is to attain win-win-win situations for the environment, farmers and water users, while preventing land speculation, are discussed. Lastly, a conceptual model for the dissemination of hydrogeological knowledge in public policies is provided, and its challenges and possibilities are discussed.
Applying the TOC Project Management to Operation and Maintenance Scheduling of a Research Vessel
NASA Astrophysics Data System (ADS)
Manti, M. Firdausi; Fujimoto, Hideo; Chen, Lian-Yi
Marine research vessels and their systems are major assets in the marine resources development. Since the running costs for the ship are very high, it is necessary to reduce the total cost by an efficient scheduling for operation and maintenance. To reduce project period and make it efficient, we applied TOC project management method that is a project management approach developed by Dr. Eli Goldratt. It challenges traditional approaches to project management. It will become the most important improvement in the project management since the development of PERT and critical path methodologies. As a case study, we presented the marine geology research project for the purpose of operations in addition to repair on the repairing dock projects for maintenance of vessels.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-26
... Maintenance Manual (AMM) includes chapters 05-10 ``Time Limits'', 05-15 ``Critical Design Configuration... 05, ``Time Limits/Maintenance Checks,'' of BAe 146 Series/AVRO 146-RJ Series Aircraft Maintenance... Chapter 05, ``Time Limits/ Maintenance Checks,'' of the BAE SYSTEMS (Operations) Limited BAe 146 Series...
5 CFR 293.108 - Rules of conduct.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Basic Policies on Maintenance of Personnel Records § 293.108 Rules of conduct. (a) Scope. These rules of conduct apply to all Office and agency employees responsible for creation, development, maintenance, processing...
DOT National Transportation Integrated Search
2017-07-01
One of the growing number of preventive bridge maintenance activities conducted by the Kentucky Transportation Cabinet (KYTC) is washing and applying thin film protective coatings to bridge abutments and piers. Previous work conducted by Kentucky Tra...
Buprenorphine does not aggravate ischemic neuronal injury in experimental focal cerebral ischemia.
Yulug, Burak; Cam, Ertugrul; Yildiz, Aysegul; Kilic, Ertugrul
2007-01-01
Buprenorphine has been increasingly used as maintenance therapy in opioid dependence as an alternative to methadone and other pharmacological therapies. However, available data suggest increased risk of cerebrovascular events in opioid-dependent patients. Therefore, an opioid that provides safety with regard to neurological function should be considered by opioid-dependent patients. The evidence for the in vitro neurotoxic effects of buprenorphine is rapidly increasing. In order to clarify whether buprenorphine is also neurotoxic under the condition of cerebral ischemia in vivo, we applied an acute dose of buprenorphine in a transient model of focal cerebral ischemia in rats. Our study provides preclinical evidence for the usage of buprenorphine during the postoperative period following ischemic events as well as for the maintenance therapy of opioid-dependent patients wherein the risk of cerebrovascular events is increased.
49 CFR 180.505 - Quality assurance program.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 2 2010-10-01 2010-10-01 false Quality assurance program. 180.505 Section 180.505... MAINTENANCE OF PACKAGINGS Qualification and Maintenance of Tank Cars § 180.505 Quality assurance program. The quality assurance program requirements of § 179.7 of this subchapter apply. ...
DOT National Transportation Integrated Search
1993-01-01
The Virginia Department of Transportation is deeply committed to the development and implementation of an efficient, cost-effective maintenance management system for its bridges. Much effort is being applied towards the development of a management sy...
Generalized random sign and alert delay models for imperfect maintenance.
Dijoux, Yann; Gaudoin, Olivier
2014-04-01
This paper considers the modelling of the process of Corrective and condition-based Preventive Maintenance, for complex repairable systems. In order to take into account the dependency between both types of maintenance and the possibility of imperfect maintenance, Generalized Competing Risks models have been introduced in "Doyen and Gaudoin (J Appl Probab 43:825-839, 2006)". In this paper, we study two classes of these models, the Generalized Random Sign and Generalized Alert Delay models. A Generalized Competing Risks model can be built as a generalization of a particular Usual Competing Risks model, either by using a virtual age framework or not. The models properties are studied and their parameterizations are discussed. Finally, simulation results and an application to real data are presented.
Myths and realities of electronics maintenance.
Harris, Douglas H
2008-06-01
The author presents and discusses discoveries and developments contributing to enhanced electronics maintenance performance. This body of research is viewed from the vantage point of Nick Bond's 1970 Ely Award-winning article in Human Factors, "Some Persistent Myths About Military Electronics Maintenance." Bond identified a set of myths and summarized research that not only produced information and techniques leading to demonstrably improved maintenance performance but also exploded many unfounded beliefs that were commonly held before the research had been conducted and the findings disseminated. The period from 1964 through 1986, as reflected by publications in the journal, was a productive period of research that led to greater understanding of human factors in electronics maintenance and to numerous advances that contributed, ultimately, to more effective maintenance performance. Technological advances, combined with what we learned about maintenance performance, have substantially reduced the maintenance burden and enhanced the maintenance of electronic systems. Some of the principal lessons learned from this research on electronics maintenance apply to understanding the effects of equipment complexity, providing an optimal role for automation, designing more appropriate on-the-job training, and enhancing troubleshooting skills.
Modeling individual differences in working memory performance: a source activation account
Daily, Larry Z.; Lovett, Marsha C.; Reder, Lynne M.
2008-01-01
Working memory resources are needed for processing and maintenance of information during cognitive tasks. Many models have been developed to capture the effects of limited working memory resources on performance. However, most of these models do not account for the finding that different individuals show different sensitivities to working memory demands, and none of the models predicts individual subjects' patterns of performance. We propose a computational model that accounts for differences in working memory capacity in terms of a quantity called source activation, which is used to maintain goal-relevant information in an available state. We apply this model to capture the working memory effects of individual subjects at a fine level of detail across two experiments. This, we argue, strengthens the interpretation of source activation as working memory capacity. PMID:19079561
Cryogenics maintenance strategy
NASA Astrophysics Data System (ADS)
Cruzat, Fabiola
2012-09-01
ALMA is an interferometer composed of 66 independent systems, with specific maintenance requirements for each subsystem. To optimize the observation time and reduce downtime maintenance, requirements are very demanding. One subsystem with high maintenance efforts is cryogenics and vacuum. To organize the maintenance, the Cryogenic and Vacuum department is using and implementing different tools. These are monitoring and problem reporting systems and CMMS. This leads to different maintenance approaches: Preventive Maintenance, Corrective Maintenance and Condition Based Maintenance. In order to coordinate activities with other departments the preventive maintenance schedule is kept as flexible as systems allow. To cope with unavoidable failures, the team has to be prepared to work under any condition with the spares on time. Computerized maintenance management system (CMMS) will help to manage inventory control for reliable spare part handling, the correct record of work orders and traceability of maintenance activities. For an optimized approach the department is currently evaluating where preventive or condition based maintenance applies to comply with the individual system demand. Considering the change from maintenance contracts to in-house maintenance will help to minimize costs and increase availability of parts. Due to increased number of system and tasks the cryo team needs to grow. Training of all staff members is mandatory, in depth knowledge must be built up by doing complex maintenance activities in the Cryo group, use of advanced computerized metrology systems.
EX.MAIN. Expert System Model for Maintenance and Staff Training.
ERIC Educational Resources Information Center
Masturzi, Elio R.
EX.MAIN, a model for maintenance and staff training which combines knowledge based expert systems and computer based training, was developed jointly by the Department of Production Engineering of the University of Naples and CIRCUMVESUVIANA, the largest private railroad in Italy. It is a global model in the maintenance field which contains both…
Modeling the impact of thermal effects on luminous flux maintenance for SSL luminaires
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Lynn; Mills, Karmann; Lamvik, Michael
Meeting the longevity requirements of solid-state lighting (SSL) devices places extreme demands on the materials and designs that are used in SSL luminaires. Therefore, understanding the aging characteristics of lens, reflectors, and other materials is essential to projecting the long-term performance of LED-based lighting systems. Overlooking these factors at either the design or product specification stage can result in premature failure of the device due to poor luminous flux maintenance and/or excessive chromaticity shifts. This paper describes a methodology for performing accelerated stress testing (AST) on materials intended for use in SSL luminaires. This test methodology, which consists of elevatedmore » temperature and humidity conditions, produces accelerated aging data that can be correlated to expected performance under normal luminaire operating conditions. The correlations can then be leveraged to produce models of the changes in the optical properties of key materials including transmittance versus wavelength of lenses and reflectance versus wavelength for housings and other reflectors. This information has been collected into a lumen maintenance decision support tool (LM-DST) and together with user supplied inputs (e.g., expected operation conditions) can provide guidance on lifetime expectations of SSL luminaires. This approach has been applied to a variety of materials commonly found in SSL luminaires including acrylics, polycarbonates, and silicones used for lenses and paints, coatings, films, and composites used for reflectors.« less
DOT National Transportation Integrated Search
2018-01-01
This project was initiated by the ODOT District 2 staff who were looking for more efficient ways to heat and operate their maintenance facilities. This especially applied to the idea of using radiant floor heating as an alternative to todays stand...
40 CFR 1048.125 - What maintenance instructions must I give to buyers?
Code of Federal Regulations, 2012 CFR
2012-07-01
... injectors, electronic control units, superchargers, and turbochargers: The useful life of the engine family... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES... and using the engine, including the emission-control system. The maintenance instructions also apply...
40 CFR 1048.125 - What maintenance instructions must I give to buyers?
Code of Federal Regulations, 2011 CFR
2011-07-01
... injectors, electronic control units, superchargers, and turbochargers: The useful life of the engine family... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES... and using the engine, including the emission-control system. The maintenance instructions also apply...
40 CFR 1048.125 - What maintenance instructions must I give to buyers?
Code of Federal Regulations, 2014 CFR
2014-07-01
... injectors, electronic control units, superchargers, and turbochargers: The useful life of the engine family... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES... and using the engine, including the emission-control system. The maintenance instructions also apply...
40 CFR 1048.125 - What maintenance instructions must I give to buyers?
Code of Federal Regulations, 2013 CFR
2013-07-01
... injectors, electronic control units, superchargers, and turbochargers: The useful life of the engine family... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES... and using the engine, including the emission-control system. The maintenance instructions also apply...
Multi-objective group scheduling optimization integrated with preventive maintenance
NASA Astrophysics Data System (ADS)
Liao, Wenzhu; Zhang, Xiufang; Jiang, Min
2017-11-01
This article proposes a single-machine-based integration model to meet the requirements of production scheduling and preventive maintenance in group production. To describe the production for identical/similar and different jobs, this integrated model considers the learning and forgetting effects. Based on machine degradation, the deterioration effect is also considered. Moreover, perfect maintenance and minimal repair are adopted in this integrated model. The multi-objective of minimizing total completion time and maintenance cost is taken to meet the dual requirements of delivery date and cost. Finally, a genetic algorithm is developed to solve this optimization model, and the computation results demonstrate that this integrated model is effective and reliable.
Sensitivity Study for Long Term Reliability
NASA Technical Reports Server (NTRS)
White, Allan L.
2008-01-01
This paper illustrates using Markov models to establish system and maintenance requirements for small electronic controllers where the goal is a high probability of continuous service for a long period of time. The system and maintenance items considered are quality of components, various degrees of simple redundancy, redundancy with reconfiguration, diagnostic levels, periodic maintenance, and preventive maintenance. Markov models permit a quantitative investigation with comparison and contrast. An element of special interest is the use of conditional probability to study the combination of imperfect diagnostics and periodic maintenance.
1989-10-19
installation. 4. Corrosion inhibiting compounds need to be applied in the final assealbly of models to all corrosion prone areas of the structure, e.g...Figure 12 shows an example of poor surface treatment of a previously repaired stringer area. Application of a corrosion inhibiting compound may have... compounds and a good corrosion control maintenance program. REFERENCE U. G. Goranson and M. Miller, "Aging Fleet - Aging Fleet Evaluation Program
Payload maintenance cost model for the space telescope
NASA Technical Reports Server (NTRS)
White, W. L.
1980-01-01
An optimum maintenance cost model for the space telescope for a fifteen year mission cycle was developed. Various documents and subsequent updates of failure rates and configurations were made. The reliability of the space telescope for one year, two and one half years, and five years were determined using the failure rates and configurations. The failure rates and configurations were also used in the maintenance simulation computer model which simulate the failure patterns for the fifteen year mission life of the space telescope. Cost algorithms associated with the maintenance options as indicated by the failure patterns were developed and integrated into the model.
Energy: Systems for Control, Maintenance, and Storage. A Bibliography.
ERIC Educational Resources Information Center
Thomas, Gerald, Comp.; McKane, Irving, Comp.
This publication is a bibliography of available periodical literature on specific aspects of energy and today's technology. The Applied Science and Technology Indexes were searched for articles that related to these specific areas: (1) Energy control systems; (2) Maintenance of Energy Systems; and (3) Energy storage. The articles and papers…
Electrical Maintenance Technician.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. Center on Education and Training for Employment.
This document contains 30 units to consider for use in a tech prep competency profile for the occupation of electrical maintenance technician. All the units listed will not necessarily apply to every situation or tech prep consortium, nor will all the competencies within each unit be appropriate. Several units appear within each specific…
14 CFR 121.1111 - Electrical wiring interconnection systems (EWIS) maintenance program.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Electrical wiring interconnection systems... Airworthiness and Safety Improvements § 121.1111 Electrical wiring interconnection systems (EWIS) maintenance program. (a) Except as provided in paragraph (f) of this section, this section applies to transport...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... Ambulatory Health Care, Inc. for Medicare Advantage Health Maintenance Organizations and Local Preferred... Accreditation Association for Ambulatory Health Care, Inc. (AAAHC) for Health Maintenance Organizations and....165(b). AOs that apply for MA deeming authority are generally recognized by the health care industry...
20 CFR 416.1143 - If you live in a noninstitutional care situation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... situation. 416.1143 Section 416.1143 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Income In-Kind Support and Maintenance § 416.1143 If you... the presumed value rule applies. You are not receiving in-kind support and maintenance and the...
20 CFR 416.1140 - The presumed value rule.
Code of Federal Regulations, 2010 CFR
2010-04-01
....1140 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Income In-Kind Support and Maintenance § 416.1140 The presumed value rule. (a) How we apply the presumed value rule. (1) When you receive in-kind support and maintenance and the one...
20 CFR 416.1143 - If you live in a noninstitutional care situation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... situation. 416.1143 Section 416.1143 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Income In-Kind Support and Maintenance § 416.1143 If you... the presumed value rule applies. You are not receiving in-kind support and maintenance and the...
Rhodes, Ryan E; Yao, Christopher A
2015-02-07
There is a growing concern among researchers with the limited effectiveness and yet subsequent stagnation of theories applied to physical activity (PA). One of the most highlighted areas of concern is the established gap between intention and PA, yet the considerable use of models that assume intention is the proximal antecedent of PA. The objective of this review was to: 1) provide a guide and thematic analysis of the available models that include constructs that address intention-behavior discordance and 2) highlight the evidence for these structures in the PA domain. A literature search was conducted among 13 major databases to locate relevant models and PA studies published before August 2014. Sixteen models were identified and nine overall themes for post-intentional constructs were created. Of the 16 models, eight were applied to 36 PA studies. Early evidence supported maintenance self-efficacy, behavioral regulation strategies, affective judgments, perceived control/opportunity, habit, and extraversion as reliable predictors of post-intention PA. Several intention-behavior discordance models exist within the literature, but are not used frequently. Further efforts are needed to test these models, preferably with experimental designs.
Application of reliability-centered-maintenance to BWR ECCS motor operator valve performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feltus, M.A.; Choi, Y.A.
1993-01-01
This paper describes the application of reliability-centered maintenance (RCM) methods to plant probabilistic risk assessment (PRA) and safety analyses for four boiling water reactor emergency core cooling systems (ECCSs): (1) high-pressure coolant injection (HPCI); (2) reactor core isolation cooling (RCIC); (3) residual heat removal (RHR); and (4) core spray systems. Reliability-centered maintenance is a system function-based technique for improving a preventive maintenance program that is applied on a component basis. Those components that truly affect plant function are identified, and maintenance tasks are focused on preventing their failures. The RCM evaluation establishes the relevant criteria that preserve system function somore » that an RCM-focused approach can be flexible and dynamic.« less
Applying an MVC Framework for The System Development Life Cycle with Waterfall Model Extended
NASA Astrophysics Data System (ADS)
Hardyanto, W.; Purwinarko, A.; Sujito, F.; Masturi; Alighiri, D.
2017-04-01
This paper describes the extension of the waterfall model using MVC architectural pattern for software development. The waterfall model is the based model of the most widely used in software development, yet there are still many problems in it. The general issue usually happens on data changes that cause the delays on the process itself. On the other hand, the security factor on the software as well as one of the major problems. This study uses PHP programming language for implementation. Although this model can be implemented in several programming languages with the same concept. This study is based on MVC architecture so that it can improve the performance of both software development and maintenance, especially concerning security, validation, database access, and routing.
Ploidally antagonistic selection maintains stable genetic polymorphism.
Immler, Simone; Arnqvist, Göran; Otto, Sarah Perin
2012-01-01
Understanding the maintenance of genetic variation in the face of selection remains a key issue in evolutionary biology. One potential mechanism for the maintenance of genetic variation is opposing selection during the diploid and haploid stages of biphasic life cycles universal among eukaryotic sexual organisms. If haploid and diploid gene expression both occur, selection can act in each phase, potentially in opposing directions. In addition, sex-specific selection during haploid phases is likely simply because male and female gametophytes/gametes tend to have contrasting life histories. We explored the potential for the maintenance of a stable polymorphism under ploidally antagonistic as well as sex-specific selection. Furthermore, we examined the role of the chromosomal location of alleles (autosomal or sex-linked). Our analyses show that the most permissible conditions for the maintenance of polymorphism occur under negative ploidy-by-sex interactions, where stronger selection for an allele in female than male diploids is coupled with weaker selection against the allele in female than male haploids. Such ploidy-by-sex interactions also promote allele frequency differences between the sexes. With constant fitness, ploidally antagonistic selection can maintain stable polymorphisms for autosomal and X-linked genes but not for Y-linked genes. We discuss the implications of our results and outline a number of biological settings where the scenarios modeled may apply. © 2011 The Author(s). Evolution © 2011 The Society for the Study of Evolution.
Nieminen, Mika; Piirainen, Sirpa; Sikström, Ulf; Löfgren, Stefan; Marttila, Hannu; Sarkkola, Sakari; Laurén, Ari; Finér, Leena
2018-03-27
The objective of this study was to evaluate the potential of different water management options to mitigate sediment and nutrient exports from ditch network maintenance (DNM) areas in boreal peatland forests. Available literature was reviewed, past data reanalyzed, effects of drainage intensity modeled, and major research gaps identified. The results indicate that excess downstream loads may be difficult to prevent. Water protection structures constructed to capture eroded matter are either inefficient (sedimentation ponds) or difficult to apply (wetland buffers). It may be more efficient to decrease erosion, either by limiting peak water velocity (dam structures) or by adjusting ditch depth and spacing to enable satisfactory drainage without exposing the mineral soil below peat. Future research should be directed towards the effects of ditch breaks and adjusted ditch depth and spacing in managing water quality in DNM areas.
State of Arts of Monumental Stones Diagnosis and Monitoring
NASA Astrophysics Data System (ADS)
Tiano, P.; Riminesi, C.
2017-08-01
The conservation and maintenance of a monumental stone building is a complex aim where different disciplines are involved. First step is concerning the determination of the state of conservation of stone material present, than determine its modification on time, as such and after conservation treatments applied on: cleaning, protecting, strengthening. In order to fulfill such objectives suitable parameters must be selected and the most appropriate diagnostic techniques for their quantitative evaluation operated. In this context, the determination of the surface water absorption, moisture content, colour variation and mechanical properties are important parameters for the control, and the monitoring over time, of the state of conservation of the monumental stone surfaces. These parameters are strongly related not only to the stone characteristics but also to the evaluation of products's performance: efficiency and durability. Their rate of variation, determined in monitoring campaigns, is fundamental for elaborate by properly predictive model a schedule maintenance protocol.
DOE Office of Scientific and Technical Information (OSTI.GOV)
The ECE application forecasts annual costs of preventive and corrective maintenance for budgeting purposes. Features within the application enable the user to change the specifications of the model to customize your forecast to best fit their needs and support “what if” analysis. Based on the user's selections, the ECE model forecasts annual maintenance costs. Preventive maintenance costs include the cost of labor to perform preventive maintenance activities at the specific frequency and labor rate. Corrective maintenance costs include the cost of labor and the cost of replacement parts. The application presents forecasted maintenance costs for the next five years inmore » two tables: costs by year and costs by site.« less
2016-01-01
Company HPT high-pressure turbine LPT low-pressure turbine MARPA Modification and Replacement Parts Association MRO maintenance , repair, and overhaul...Corporation R® is a registered trademark. Cover image: A KC-10 F103 (CF6-50) engine at the MTU Vancouver facility (courtesy of MTU Maintenance Canada Ltd...representative (DER) repairs to decrease the cost of their aircraft engine maintenance . These parts and repairs are provided by third-party companies and
41 CFR 102-71.20 - What definitions apply to GSA's real property policies?
Code of Federal Regulations, 2011 CFR
2011-01-01
... changes to a facility, exclusive of maintenance repairs that are preventive in nature. The term includes... cycle cost is the total cost of owning, operating, and maintaining a building over its useful life... Characteristics of Building Materials. Maintenance, for the purposes of part 102-75, entitled “Real Property...
41 CFR 102-71.20 - What definitions apply to GSA's real property policies?
Code of Federal Regulations, 2014 CFR
2014-01-01
... changes to a facility, exclusive of maintenance repairs that are preventive in nature. The term includes... cycle cost is the total cost of owning, operating, and maintaining a building over its useful life... Characteristics of Building Materials. Maintenance, for the purposes of part 102-75, entitled “Real Property...
40 CFR 63.9000 - What emission limitations and work practice standards must I meet?
Code of Federal Regulations, 2010 CFR
2010-07-01
... of Hazardous Waste in Boilers and Industrial Furnaces. (d) The emission limits for HCl storage tanks in table 1 to this subpart do not apply during periods of planned routine maintenance of HCl storage tank control devices. Periods of planned routine maintenance of each HCl storage tank control device...
ERIC Educational Resources Information Center
Texas State Technical Coll., Waco.
A project was conducted to determine if interactive video programs could produce positive results in literacy programs. During the project, staff from a technical college developed a task analysis, curriculum, and evaluation measures for the training of facilities maintenance workers in mathematical concepts. From this activity, an instructional…
40 CFR 86.432-78 - Deterioration factor.
Code of Federal Regulations, 2013 CFR
2013-07-01
... apply the outlier procedure to a data set containing data which were averaged under § 86.427-78(e), the... be developed for each pollutant. The applicable data to be used in calculating these factors are: (1... maintenance, if approval of the maintenance by the Administrator was conditioned on the data being used in the...
40 CFR 86.432-78 - Deterioration factor.
Code of Federal Regulations, 2011 CFR
2011-07-01
... apply the outlier procedure to a data set containing data which were averaged under § 86.427-78(e), the... be developed for each pollutant. The applicable data to be used in calculating these factors are: (1... maintenance, if approval of the maintenance by the Administrator was conditioned on the data being used in the...
40 CFR 86.432-78 - Deterioration factor.
Code of Federal Regulations, 2010 CFR
2010-07-01
... apply the outlier procedure to a data set containing data which were averaged under § 86.427-78(e), the... be developed for each pollutant. The applicable data to be used in calculating these factors are: (1... maintenance, if approval of the maintenance by the Administrator was conditioned on the data being used in the...
40 CFR 86.432-78 - Deterioration factor.
Code of Federal Regulations, 2014 CFR
2014-07-01
... apply the outlier procedure to a data set containing data which were averaged under § 86.427-78(e), the... be developed for each pollutant. The applicable data to be used in calculating these factors are: (1... maintenance, if approval of the maintenance by the Administrator was conditioned on the data being used in the...
40 CFR 86.432-78 - Deterioration factor.
Code of Federal Regulations, 2012 CFR
2012-07-01
... apply the outlier procedure to a data set containing data which were averaged under § 86.427-78(e), the... be developed for each pollutant. The applicable data to be used in calculating these factors are: (1... maintenance, if approval of the maintenance by the Administrator was conditioned on the data being used in the...
34 CFR 403.182 - What is the maintenance of fiscal effort requirement?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 3 2010-07-01 2010-07-01 false What is the maintenance of fiscal effort requirement? 403.182 Section 403.182 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF VOCATIONAL AND ADULT EDUCATION, DEPARTMENT OF EDUCATION STATE VOCATIONAL AND APPLIED TECHNOLOGY...
Oracle Applications Patch Administration Tool (PAT) Beta Version
DOE Office of Scientific and Technical Information (OSTI.GOV)
2002-01-04
PAT is a Patch Administration Tool that provides analysis, tracking, and management of Oracle Application patches. This includes capabilities as outlined below: Patch Analysis & Management Tool Outline of capabilities: Administration Patch Data Maintenance -- track Oracle Application patches applied to what database instance & machine Patch Analysis capture text files (readme.txt and driver files) form comparison detail report comparison detail PL/SQL package comparison detail SQL scripts detail JSP module comparison detail Parse and load the current applptch.txt (10.7) or load patch data from Oracle Application database patch tables (11i) Display Analysis -- Compare patch to be applied with currentmore » Oracle Application installed Appl_top code versions Patch Detail Module comparison detail Analyze and display one Oracle Application module patch. Patch Management -- automatic queue and execution of patches Administration Parameter maintenance -- setting for directory structure of Oracle Application appl_top Validation data maintenance -- machine names and instances to patch Operation Patch Data Maintenance Schedule a patch (queue for later execution) Run a patch (queue for immediate execution) Review the patch logs Patch Management Reports« less
Operation and maintenance results from ISFOC CPV plants
NASA Astrophysics Data System (ADS)
Gil, Eduardo; Martinez, María; de la Rubia, Oscar
2017-09-01
The analysis of field operation and maintenance data collected during a period of over eight years, from CPV installations consisting of three different CPV technologies (including second generation of one of these technologies), has allowed us to get valuable information about the long-term degradation of the CPV systems. Through the study of the maintenance control ratio previously defined and by applying the root cause analysis methodology, the components responsible for the most unplanned interventions for each technology were identified. Focusing maintenance efforts on these components, a reduction of the unplanned interventions and the total cost of maintenance has been achieved over the years. Therefore, the deployment of an effective maintenance plan, identifying critical components, is essential to minimize the risk for investors and maximize the CPV power plants lifetime and energy output, increasing the availability of CPV installations, boosting market confidence in CPV systems.
76 FR 67633 - Airworthiness Directives; Dassault Aviation Model Mystere-Falcon 50 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-02
...) of section 5-10 of the Recommended Maintenance Schedules chapter of the Aircraft Maintenance...) of section 5-10 of the Recommended Maintenance Schedules chapter of the Aircraft Maintenance... Dassault Falcon 50/ 50EX Maintenance Procedure 57-607, Non-Destructive Check of Flap Tracks 2 and 5, of...
Maintaining close relationships: gratitude as a motivator and a detector of maintenance behavior.
Kubacka, Kaska E; Finkenauer, Catrin; Rusbult, Caryl E; Keijsers, Loes
2011-10-01
This research examined the dual function of gratitude for relationship maintenance in close relationships. In a longitudinal study among married couples, the authors tested the dyadic effects of gratitude over three time points for approximately 4 years following marriage. They found that feelings of gratitude toward a partner stem from the partner's relationship maintenance behaviors, partly because such behaviors create the perception of responsiveness to one's needs. In turn, gratitude motivates partners to engage in relationship maintenance. Hence, the present model emphasizes that gratitude between close partners (a) originates from partners' relationship maintenance behaviors and the perception of a partner's responsiveness and (b) promotes a partner's reciprocal maintenance behaviors. Thus, the authors' findings add credence to their model, in that gratitude contributes to a reciprocal process of relationship maintenance, whereby each partner's maintenance behaviors, perceptions of responsiveness, and feelings of gratitude feed back on and influence the other's behaviors, perceptions, and feelings.
Three essays on energy and environmental economics: Empirical, applied, and theoretical
NASA Astrophysics Data System (ADS)
Karney, Daniel Houghton
Energy and environmental economics are closely related fields as nearly all forms of energy production generate pollution and thus nearly all forms of environmental policy affect energy production and consumption. The three essays in this dissertation are related by their common themes of energy and environmental economics, but they differ in their methodologies. The first chapter is an empirical exercise that looks that the relationship between electricity price deregulation and maintenance outages at nuclear power plants. The second chapter is an applied theory paper that investigates environmental regulation in a multiple pollutants setting. The third chapter develops a new methodology regarding the construction of analytical general equilibrium models that can be used to study topics in energy and environmental economics.
3D web based learning of medical equipment employed in intensive care units.
Cetin, Aydın
2012-02-01
In this paper, both synchronous and asynchronous web based learning of 3D medical equipment models used in hospital intensive care unit have been described over the moodle course management system. 3D medical equipment models were designed with 3ds Max 2008, then converted to ASE format and added interactivity displayed with Viewpoint-Enliven. 3D models embedded in a web page in html format with dynamic interactivity-rotating, panning and zooming by dragging a mouse over images-and descriptive information is embedded to 3D model by using xml format. A pilot test course having 15 h was applied to technicians who is responsible for intensive care unit at Medical Devices Repairing and Maintenance Center (TABOM) of Turkish High Specialized Hospital.
A distribution model for the aerial application of granular agricultural particles
NASA Technical Reports Server (NTRS)
Fernandes, S. T.; Ormsbee, A. I.
1978-01-01
A model is developed to predict the shape of the distribution of granular agricultural particles applied by aircraft. The particle is assumed to have a random size and shape and the model includes the effect of air resistance, distributor geometry and aircraft wake. General requirements for the maintenance of similarity of the distribution for scale model tests are derived and are addressed to the problem of a nongeneral drag law. It is shown that if the mean and variance of the particle diameter and density are scaled according to the scaling laws governing the system, the shape of the distribution will be preserved. Distributions are calculated numerically and show the effect of a random initial lateral position, particle size and drag coefficient. A listing of the computer code is included.
Measuring test productivity - The elusive dream
NASA Astrophysics Data System (ADS)
Ward, D. T.; Cross, E. J., Jr.
1983-11-01
The paper summarizes definitions and terminology relating to measurement of Test and Evaluation productivity before settling on the appropriate criteria for such a measurement model. A productivity measurement scheme suited for use by Test and Evaluation organizations is suggested. This mathematical model is a simplified version of one proposed by the American Productivity Center and applied to an aircraft maintenance facility by Fletcher. It includes only four primary variables: safety, schedule, cost, and deficiencies reported with varying degrees of objectivity and subjectivity involved in quantifying them. A hypothetical example of a fighter aircraft flight test program is used to illustrate the application of the productivity measurement model. The proposed model is intended to serve as a first iteration procedure and should be tested against real test programs to verify and refine it.
Model of the Product Development Lifecycle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
He, Sunny L.; Roe, Natalie H.; Wood, Evan
2015-10-01
While the increased use of Commercial Off-The-Shelf information technology equipment has presented opportunities for improved cost effectiveness and flexibility, the corresponding loss of control over the product's development creates unique vulnerabilities and security concerns. Of particular interest is the possibility of a supply chain attack. A comprehensive model for the lifecycle of hardware and software products is proposed based on a survey of existing literature from academic, government, and industry sources. Seven major lifecycle stages are identified and defined: (1) Requirements, (2) Design, (3) Manufacturing for hardware and Development for software, (4) Testing, (5) Distribution, (6) Use and Maintenance, andmore » (7) Disposal. The model is then applied to examine the risk of attacks at various stages of the lifecycle.« less
Understanding and Predicting the Process of Software Maintenance Releases
NASA Technical Reports Server (NTRS)
Basili, Victor; Briand, Lionel; Condon, Steven; Kim, Yong-Mi; Melo, Walcelio L.; Valett, Jon D.
1996-01-01
One of the major concerns of any maintenance organization is to understand and estimate the cost of maintenance releases of software systems. Planning the next release so as to maximize the increase in functionality and the improvement in quality are vital to successful maintenance management. The objective of this paper is to present the results of a case study in which an incremental approach was used to better understand the effort distribution of releases and build a predictive effort model for software maintenance releases. This study was conducted in the Flight Dynamics Division (FDD) of NASA Goddard Space Flight Center(GSFC). This paper presents three main results: 1) a predictive effort model developed for the FDD's software maintenance release process; 2) measurement-based lessons learned about the maintenance process in the FDD; and 3) a set of lessons learned about the establishment of a measurement-based software maintenance improvement program. In addition, this study provides insights and guidelines for obtaining similar results in other maintenance organizations.
NASA Technical Reports Server (NTRS)
1999-01-01
Sentel Corporation has commercialized NASA's Electronic Portable Information Collection (EPIC) System, which stemmed from a NASA Kennedy Space Center SBIR contract. NASA and Sentel designed, built, and tested work authorization procedures used as a paperless procedures system for Space Shuttle and International Space Station payload processing operations. EPIC is now being applied to various markets including; airplane maintenance, aerospace system data management, shipbuilding industries, shipping industries, law enforcement agencies, and public utilities. KSC is planning a pilot program to use EPIC at the Hypergol Maintenance Facility. In addition, Ames Research Center and KSC are working together to apply EPIC to the area of wireless communication.
25 CFR 171.105 - Does this part apply to me?
Code of Federal Regulations, 2013 CFR
2013-04-01
... 25 Indians 1 2013-04-01 2013-04-01 false Does this part apply to me? 171.105 Section 171.105 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE General Provisions § 171.105 Does this part apply to me? This part applies to you if you own or...
25 CFR 171.105 - Does this part apply to me?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 1 2010-04-01 2010-04-01 false Does this part apply to me? 171.105 Section 171.105 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE General Provisions § 171.105 Does this part apply to me? This part applies to you if you own or...
25 CFR 171.105 - Does this part apply to me?
Code of Federal Regulations, 2012 CFR
2012-04-01
... 25 Indians 1 2012-04-01 2011-04-01 true Does this part apply to me? 171.105 Section 171.105 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE General Provisions § 171.105 Does this part apply to me? This part applies to you if you own or...
25 CFR 171.105 - Does this part apply to me?
Code of Federal Regulations, 2011 CFR
2011-04-01
... 25 Indians 1 2011-04-01 2011-04-01 false Does this part apply to me? 171.105 Section 171.105 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE General Provisions § 171.105 Does this part apply to me? This part applies to you if you own or...
Buildings Lean Maintenance Implementation Model
NASA Astrophysics Data System (ADS)
Abreu, Antonio; Calado, João; Requeijo, José
2016-11-01
Nowadays, companies in global markets have to achieve high levels of performance and competitiveness to stay "alive".Within this assumption, the building maintenance cannot be done in a casual and improvised way due to the costs related. Starting with some discussion about lean management and building maintenance, this paper introduces a model to support the Lean Building Maintenance (LBM) approach. Finally based on a real case study from a Portuguese company, the benefits, challenges and difficulties are presented and discussed.
20 CFR 416.1141 - When the presumed value rule applies.
Code of Federal Regulations, 2011 CFR
2011-04-01
....1141 Section 416.1141 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Income In-Kind Support and Maintenance § 416.1141 When the presumed value rule applies. The presumed value rule applies whenever we must count in-kind support and...
20 CFR 416.1141 - When the presumed value rule applies.
Code of Federal Regulations, 2010 CFR
2010-04-01
....1141 Section 416.1141 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Income In-Kind Support and Maintenance § 416.1141 When the presumed value rule applies. The presumed value rule applies whenever we must count in-kind support and...
NASA Astrophysics Data System (ADS)
Belkhode, Pramod Namdeorao
2017-06-01
Field data based model is proposed to reduce the overhauling time and human energy consumed in liner piston maintenance activity so as to increase the productivity of liner piston maintenance activity. The independent variables affecting the phenomenon such as anthropometric parameters of workers (Eastman Kodak Co. Ltd in Section VIA Appendix-A: Anthropometric Data. Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 1), workers parameters, specification of liner piston data, specification of tools used in liner piston maintenance activity, specification of solvents, axial clearance of big end bearing and bolt elongation, workstation data (Eastman Kodak Co. Ltd in Work Place Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 2) and extraneous variables, namely, temperature, humidity at workplace, illumination at workplace and noise at workplace (Eastman Kodak Co. Ltd in Chapter V Environment Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 3) are taken into account. The model is formulated for dependent variables of liner piston maintenance activity to minimize the overhauling time and human energy consumption so as to improve the productivity of liner piston maintenance activity. The developed model can predict the performance of liner piston maintenance activity which involves man and machine system (Schenck in Theories of Engineering Experimentation, Mc-Graw Hill, New York 4). The model is then optimized by optimization technique and the sensitivity analysis of the model has also been estimated.
Computer modeling of the stress-strain state of welded construction
NASA Astrophysics Data System (ADS)
Nurguzhin, Marat; Danenova, Gulmira; Akhmetzhanov, Talgat
2017-11-01
At the present time the maintenance of the welded construction serviceability over normative service life is provided by the maintenance system on the basis of the guiding documents according to the concept of "fail safe". However, technology factors relating to welding such as high residual stresses and significant plastic strains are not considered in the guiding documents. The design procedure of the stressed-strained state of welded constructions is suggested in the paper. The procedure investigates welded constructions during welding and the external load using the program ANSYS. In this paper, the model of influence of the residual stress strain state on the factor of stress intensity is proposed. The calculation method of the residual stressed-strained state (SSS) taking into account the phase transition is developed by the authors. Melting and hardening of a plate material during heating and cooling is considered. The thermomechanical problem of heating a plate by a stationary heat source is solved. The setup of the heating spot center on distance (190 mm) from the crack top in a direction of its propagation leads to the fact that the value of total factor of stress intensity will considerably decrease under action of the specified residual compressing stresses. It can lower the speed of the crack propagation to zero. The suggested method of survivability maintenance can be applied during operation with the purpose of increasing the service life of metal constructions up to running repair of technological machines.
Applying theory of planned behavior to predict exercise maintenance in sarcopenic elderly.
Ahmad, Mohamad Hasnan; Shahar, Suzana; Teng, Nur Islami Mohd Fahmi; Manaf, Zahara Abdul; Sakian, Noor Ibrahim Mohd; Omar, Baharudin
2014-01-01
This study aimed to determine the factors associated with exercise behavior based on the theory of planned behavior (TPB) among the sarcopenic elderly people in Cheras, Kuala Lumpur. A total of 65 subjects with mean ages of 67.5±5.2 (men) and 66.1±5.1 (women) years participated in this study. Subjects were divided into two groups: 1) exercise group (n=34; 25 men, nine women); and 2) the control group (n=31; 22 men, nine women). Structural equation modeling, based on TPB components, was applied to determine specific factors that most contribute to and predict actual behavior toward exercise. Based on the TPB's model, attitude (β=0.60) and perceived behavioral control (β=0.24) were the major predictors of intention to exercise among men at the baseline. Among women, the subjective norm (β=0.82) was the major predictor of intention to perform the exercise at the baseline. After 12 weeks, attitude (men's, β=0.68; women's, β=0.24) and subjective norm (men's, β=0.12; women's, β=0.87) were the predictors of the intention to perform the exercise. "Feels healthier with exercise" was the specific factor to improve the intention to perform and to maintain exercise behavior in men (β=0.36) and women (β=0.49). "Not motivated to perform exercise" was the main barrier among men's intention to exercise. The intention to perform the exercise was able to predict actual behavior regarding exercise at the baseline and at 12 weeks of an intervention program. As a conclusion, TPB is a useful model to determine and to predict maintenance of exercise in the sarcopenic elderly.
Applying theory of planned behavior to predict exercise maintenance in sarcopenic elderly
Ahmad, Mohamad Hasnan; Shahar, Suzana; Teng, Nur Islami Mohd Fahmi; Manaf, Zahara Abdul; Sakian, Noor Ibrahim Mohd; Omar, Baharudin
2014-01-01
This study aimed to determine the factors associated with exercise behavior based on the theory of planned behavior (TPB) among the sarcopenic elderly people in Cheras, Kuala Lumpur. A total of 65 subjects with mean ages of 67.5±5.2 (men) and 66.1±5.1 (women) years participated in this study. Subjects were divided into two groups: 1) exercise group (n=34; 25 men, nine women); and 2) the control group (n=31; 22 men, nine women). Structural equation modeling, based on TPB components, was applied to determine specific factors that most contribute to and predict actual behavior toward exercise. Based on the TPB’s model, attitude (β=0.60) and perceived behavioral control (β=0.24) were the major predictors of intention to exercise among men at the baseline. Among women, the subjective norm (β=0.82) was the major predictor of intention to perform the exercise at the baseline. After 12 weeks, attitude (men’s, β=0.68; women’s, β=0.24) and subjective norm (men’s, β=0.12; women’s, β=0.87) were the predictors of the intention to perform the exercise. “Feels healthier with exercise” was the specific factor to improve the intention to perform and to maintain exercise behavior in men (β=0.36) and women (β=0.49). “Not motivated to perform exercise” was the main barrier among men’s intention to exercise. The intention to perform the exercise was able to predict actual behavior regarding exercise at the baseline and at 12 weeks of an intervention program. As a conclusion, TPB is a useful model to determine and to predict maintenance of exercise in the sarcopenic elderly. PMID:25258524
Integrating O/S models during conceptual design, part 3
NASA Technical Reports Server (NTRS)
Ebeling, Charles E.
1994-01-01
Space vehicles, such as the Space Shuttle, require intensive ground support prior to, during, and after each mission. Maintenance is a significant part of that ground support. All space vehicles require scheduled maintenance to ensure operability and performance. In addition, components of any vehicle are not one-hundred percent reliable so they exhibit random failures. Once detected, a failure initiates unscheduled maintenance on the vehicle. Maintenance decreases the number of missions which can be completed by keeping vehicles out of service so that the time between the completion of one mission and the start of the next is increased. Maintenance also requires resources such as people, facilities, tooling, and spare parts. Assessing the mission capability and resource requirements of any new space vehicle, in addition to performance specification, is necessary to predict the life cycle cost and success of the vehicle. Maintenance and logistics support has been modeled by computer simulation to estimate mission capability and resource requirements for evaluation of proposed space vehicles. The simulation was written with Simulation Language for Alternative Modeling II (SLAM II) for execution on a personal computer. For either one or a fleet of space vehicles, the model simulates the preflight maintenance checks, the mission and return to earth, and the post flight maintenance in preparation to be sent back into space. THe model enables prediction of the number of missions possible and vehicle turn-time (the time between completion of one mission and the start of the next) given estimated values for component reliability and maintainability. The model also facilitates study of the manpower and vehicle requirements for the proposed vehicle to meet its desired mission rate. This is the 3rd part of a 3 part technical report.
Code of Federal Regulations, 2010 CFR
2010-07-01
... VOCATIONAL AND APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403... 34 Education 3 2010-07-01 2010-07-01 false Under what circumstances may the Secretary waive the maintenance of effort requirement? 403.183 Section 403.183 Education Regulations of the Offices of the...
ERIC Educational Resources Information Center
Rigney, J. W.; And Others
This report describes the Generalized Maintenance Trainer-Simulator (GMTS), an instructional system designed to give electronics students intensive troubleshooting practice in a simulated hands-on training environment, and reports on a field evaluation of the GMTS applied to systems level troubleshooting in radio communications. The GMTS can be…
Maintenance = reuse-oriented software development
NASA Technical Reports Server (NTRS)
Basili, Victor R.
1989-01-01
Maintenance is viewed as a reuse process. In this context, a set of models that can be used to support the maintenance process is discussed. A high level reuse framework is presented that characterizes the object of reuse, the process for adapting that object for its target application, and the reused object within its target application. Based upon this framework, a qualitative comparison is offered of the three maintenance process models with regard to their strengths and weaknesses and the circumstances in which they are appropriate. To provide a more systematic, quantitative approach for evaluating the appropriateness of the particular maintenance model, a measurement scheme is provided, based upon the reuse framework, in the form of an organized set of questions that need to be answered. To support the reuse perspective, a set of reuse enablers are discussed.
NASA Astrophysics Data System (ADS)
Goldberg, D. N.; Snow, K.; Holland, P.; Jordan, J. R.; Campin, J.-M.; Heimbach, P.; Arthern, R.; Jenkins, A.
2018-05-01
Synchronous coupling is developed between an ice sheet model and a z-coordinate ocean model (the MITgcm). A previously-developed scheme to allow continuous vertical movement of the ice-ocean interface of a floating ice shelf ("vertical coupling") is built upon to allow continuous movement of the grounding line, or point of floatation of the ice sheet ("horizontal coupling"). Horizontal coupling is implemented through the maintenance of a thin layer of ocean ( ∼ 1 m) under grounded ice, which is inflated into the real ocean as the ice ungrounds. This is accomplished through a modification of the ocean model's nonlinear free surface evolution in a manner akin to a hydrological model in the presence of steep bathymetry. The coupled model is applied to a number of idealized geometries and shown to successfully represent ocean-forced marine ice sheet retreat while maintaining a continuous ocean circulation.
Development of the salt-reduction and efficacy-maintenance program in Indonesia.
Irwan, Andi Masyitha; Kato, Mayumi; Kitaoka, Kazuyo; Ueno, Eiichi; Tsujiguchi, Hiromasa; Shogenji, Miho
2016-12-01
We conducted a randomized, controlled trial to examine the effects of a salt-reduction and efficacy-maintenance program on the improvement and maintenance of self-care and self-efficacy in reducing the salt intake of older people with high blood pressure. A total of 51 participants with hypertension/prehypertension in Indonesia were randomly assigned to a control group or one of two intervention groups: salt-reduction training or salt-reduction and efficacy-maintenance. The salt-reduction and efficacy-maintenance group received educational training and a maintenance meeting; the participants' knowledge, attitudes, self-care practices, and self-efficacy significantly improved after training and were maintained after the maintenance meeting. Participants in the salt-reduction training group showed significant effects for the same variables; however, their food salt concentrations rebounded after the maintenance meeting. No significant improvement was found in the control group. The salt-reduction and efficacy-maintenance group participants reported positive effects of salt reduction and different practices based on who prepared their meals. The salt-reduction and efficacy-maintenance group program was effective in improving and maintaining knowledge, attitudes, and self-efficacy of salt-reduction practices and could be applied with community-dwelling older people with high blood pressure. © 2016 John Wiley & Sons Australia, Ltd.
Computational simulation of laser heat processing of materials
NASA Astrophysics Data System (ADS)
Shankar, Vijaya; Gnanamuthu, Daniel
1987-04-01
A computational model simulating the laser heat treatment of AISI 4140 steel plates with a CW CO2 laser beam has been developed on the basis of the three-dimensional, time-dependent heat equation (subject to the appropriate boundary conditions). The solution method is based on Newton iteration applied to a triple-approximate factorized form of the equation. The method is implicit and time-accurate; the maintenance of time-accuracy in the numerical formulation is noted to be critical for the simulation of finite length workpieces with a finite laser beam dwell time.
Theory-based interventions in physical activity: a systematic review of literature in Iran.
Abdi, Jalal; Eftekhar, Hassan; Estebsari, Fatemeh; Sadeghi, Roya
2014-11-30
Lack of physical activity is ranked fourth among the causes of human death and chronic diseases. Using models and theories to design, implement, and evaluate the health education and health promotion interventions has many advantages. Using models and theories of physical activity, we decided to systematically study the educational and promotional interventions carried out in Iran from 2003 to 2013.Three information databases were used to systematically select papers using key words including Iranian Magazine Database (MAGIRAN), Iran Medical Library (MEDLIB), and Scientific Information Database (SID). Twenty papers were selected and studied .Having been applied in 9 studies, The Trans Theoretical Model (TTM) was the most widespread model in Iran (PENDER in 3 studies, BASNEF in 2, and the Theory of Planned Behavior in 2 studies). With regards to the educational methods, almost all studies used a combination of methods. The most widely used Integrative educational method was group discussion. Only one integrated study was done. Behavior maintenance was not addressed in 75% of the studies. Almost all studies used self-reporting instruments. The effectiveness of educational methods was assessed in none of the studies. Most of the included studies had several methodological weaknesses, which hinder the validity and applicability of their results. According to the findings, the necessity of need assessment in using models, epidemiology and methodology consultation, addressing maintenance of physical activity, using other theories and models such as social marketing and social-cognitive theory, and other educational methods like empirical and complementary are suggested.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Liping; Hong, Tianzhen
Almost half of the total energy used in the U.S. buildings is consumed by heating, ventilation and air conditionings (HVAC) according to EIA statistics. Among various driving factors to energy performance of building, operations and maintenance play a significant role. Many researches have been done to look at design efficiencies and operational controls for improving energy performance of buildings, but very few study the impacts of HVAC systems maintenance. Different practices of HVAC system maintenance can result in substantial differences in building energy use. If a piece of HVAC equipment is not well maintained, its performance will degrade. If sensorsmore » used for control purpose are not calibrated, not only building energy usage could be dramatically increased, but also mechanical systems may not be able to satisfy indoor thermal comfort. Properly maintained HVAC systems can operate efficiently, improve occupant comfort, and prolong equipment service life. In the paper, maintenance practices for HVAC systems are presented based on literature reviews and discussions with HVAC engineers, building operators, facility managers, and commissioning agents. We categorize the maintenance practices into three levels depending on the maintenance effort and coverage: 1) proactive, performance-monitored maintenance; 2) preventive, scheduled maintenance; and 3) reactive, unplanned or no maintenance. A sampled list of maintenance issues, including cooling tower fouling, boiler/chiller fouling, refrigerant over or under charge, temperature sensor offset, outdoor air damper leakage, outdoor air screen blockage, outdoor air damper stuck at fully open position, and dirty filters are investigated in this study using field survey data and detailed simulation models. The energy impacts of both individual maintenance issue and combined scenarios for an office building with central VAV systems and central plant were evaluated by EnergyPlus simulations using three approaches: 1) direct modeling with EnergyPlus, 2) using the energy management system feature of EnergyPlus, and 3) modifying EnergyPlus source code. The results demonstrated the importance of maintenance for HVAC systems on energy performance of buildings. The research is intended to provide a guideline to help practitioners and building operators to gain the knowledge of maintaining HVAC systems in efficient operations, and prioritize HVAC maintenance work plan. The paper also discusses challenges of modeling building maintenance issues using energy simulation programs.« less
The Sortie-Generation Model System. Volume 5. Maintenance Subsystem
1981-09-01
Compuger RoanutI f and moidel 11, Computer operatinS system 17, Proorammino largualviso IS. Numlier of .ugic proltsm Hoewl -3 CSCobol 600 stuscomentm...THE SORTIE-GENERATION MODEL SYSTEM OC’ VOLUME V MAINTENANCE SUBSYSTEM September 1981 Robert S. Greenberg 05$ Prepared pursuant to Department of...Generation Model System Volume V Maintenance Subsystem 6. PERFORMING ORG. REPORT NUMBER LMI Task- L102 7. AUTHOR(a) 8. CONTRACT OR GRANT NUMBER(a
Kawatsu, Kazutaka
2013-02-01
The assumption of a twofold cost of sex not only complicates the maintenance of sex but also sets conditions for sexual conflict: in organisms with the twofold cost, males often sexually harass females. Sexual harassment is detrimental to female fitness and thus might help maintain sexual populations if male harassment inflicts a harsher cost on parthenogens than on sexual females (asymmetric harassment cost). However, the generality of this concept is now considered doubtful because selective harassment of parthenogens results in loss of mating opportunities for males. Using three mathematical models, I show here that sexual harassment still can impose the asymmetric cost on parthenogens. First, I apply the Lotka-Volterra model to show the degree of asymmetric harassment cost that permits sex to be maintained stably in the population. Second, using adaptive dynamics, I examine whether sexually antagonistic coevolution for sexual harassment, which occurs only in sexual populations, can promote the asymmetric harassment cost. Finally, an individual-based model, which assumes a spatial structure unlike that in the other two, demonstrates that the asymmetric evolution of harassment cost prevents further invasions of parthenogens from different patches into sexual lineages; these mechanisms may account for allopatric distributions of sexual and parthenogenetic lineages as well as the maintenance of sex.
Chien, T W; Chu, H; Hsu, W C; Tseng, T K; Hsu, C H; Chen, K Y
2003-08-01
The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.
McDaniel, Jamie L
2013-12-01
This exploration of disability directly applies Campbell's understanding of "abledness" to the film Phenomena by Italian director Dario Argento. Phenomena (1985) explores, through the diegetic response to protagonist Jennifer Corvino's ability to communicate with insects, the shifting cultural association between disability and deviance. The film begins with the traditional response to disability, what education psychologist Kaoru Yamamoto considers the cultural importance of classifying and interpreting disabled bodies by fitting them into a narrative of deviance for surveillance and control. Throughout Argento's film, characters attempt to classify Jennifer; scientists seek to diagnose her "affliction" through the medical model of disability, while Jennifer's schoolmistresses interpret Jennifer's behavior as a disciplinary problem based in environmental factors. This represents the structural model of disability, but in each instance, the attempt to classify Jennifer fails to diagnose or discipline the supposed "deviant, disabled body." Through this failure, the film dramatizes contemporary critiques of traditional models that examine disability, moving beyond to explore what Fiona Kumari Campbell has called "the maintenance of abledness" in sexed, raced, and modified bodies. By normalizing Jennifer's ability, then, Phenomena offers a framework for examining the process through which elements of "abledness" become normalized, a concept which many theorists now argue should maintain the focus of disability studies.
Architecture and Key Techniques of Augmented Reality Maintenance Guiding System for Civil Aircrafts
NASA Astrophysics Data System (ADS)
hong, Zhou; Wenhua, Lu
2017-01-01
Augmented reality technology is introduced into the maintenance related field for strengthened information in real-world scenarios through integration of virtual assistant maintenance information with real-world scenarios. This can lower the difficulty of maintenance, reduce maintenance errors, and improve the maintenance efficiency and quality of civil aviation crews. Architecture of augmented reality virtual maintenance guiding system is proposed on the basis of introducing the definition of augmented reality and analyzing the characteristics of augmented reality virtual maintenance. Key techniques involved, such as standardization and organization of maintenance data, 3D registration, modeling of maintenance guidance information and virtual maintenance man-machine interaction, are elaborated emphatically, and solutions are given.
Methods of increasing efficiency and maintainability of pipeline systems
NASA Astrophysics Data System (ADS)
Ivanov, V. A.; Sokolov, S. M.; Ogudova, E. V.
2018-05-01
This study is dedicated to the issue of pipeline transportation system maintenance. The article identifies two classes of technical-and-economic indices, which are used to select an optimal pipeline transportation system structure. Further, the article determines various system maintenance strategies and strategy selection criteria. Meanwhile, the maintenance strategies turn out to be not sufficiently effective due to non-optimal values of maintenance intervals. This problem could be solved by running the adaptive maintenance system, which includes a pipeline transportation system reliability improvement algorithm, especially an equipment degradation computer model. In conclusion, three model building approaches for determining optimal technical systems verification inspections duration were considered.
Ecological investigations: vegetation studies, preliminary findings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olgeirson, E.R.; Martin, R.B.
1978-09-01
The objective of the vegetation studies conducted on the research site is to produce a descriptive data base that can be applied to determinations of carrying capacity of the site and surrounding area. Additional information obtained about parameters that influence vegetation growth and maintenance of soil nutrients, and moisture and temperature regimes help define dynamic relationships that must be understood to effect successful revegetation and habitat rehabilitation. The descriptive vegetation baseline also provides a point of departure for design of future monitoring programs, and predictive models and strategies to be used in dealing with impact mitigation; in turn, monitoring programsmore » and predictive modeling form the bases for making distinctions between natural trends and man-induced perturbations.« less
Pavement maintenance optimization model using Markov Decision Processes
NASA Astrophysics Data System (ADS)
Mandiartha, P.; Duffield, C. F.; Razelan, I. S. b. M.; Ismail, A. b. H.
2017-09-01
This paper presents an optimization model for selection of pavement maintenance intervention using a theory of Markov Decision Processes (MDP). There are some particular characteristics of the MDP developed in this paper which distinguish it from other similar studies or optimization models intended for pavement maintenance policy development. These unique characteristics include a direct inclusion of constraints into the formulation of MDP, the use of an average cost method of MDP, and the policy development process based on the dual linear programming solution. The limited information or discussions that are available on these matters in terms of stochastic based optimization model in road network management motivates this study. This paper uses a data set acquired from road authorities of state of Victoria, Australia, to test the model and recommends steps in the computation of MDP based stochastic optimization model, leading to the development of optimum pavement maintenance policy.
Evaluation and specification of high build and special use waterborne pavement markings.
DOT National Transportation Integrated Search
2014-01-01
High build waterborne traffic paints and highly retro-reflective elements were applied at various locations to evaluate their : practicality for use by NYSDOT Maintenance forces. In addition, highly reflective elements were applied within grooved in ...
Value of information of repair times for offshore wind farm maintenance planning
NASA Astrophysics Data System (ADS)
Seyr, Helene; Muskulus, Michael
2016-09-01
A large contribution to the total cost of energy in offshore wind farms is due to maintenance costs. In recent years research has focused therefore on lowering the maintenance costs using different approaches. Decision support models for scheduling the maintenance exist already, dealing with different factors influencing the scheduling. Our contribution deals with the uncertainty in the repair times. Given the mean repair times for different turbine components we make some assumptions regarding the underlying repair time distribution. We compare the results of a decision support model for the mean times to repair and those repair time distributions. Additionally, distributions with the same mean but different variances are compared under the same conditions. The value of lowering the uncertainty in the repair time is calculated and we find that using distributions significantly decreases the availability, when scheduling maintenance for multiple turbines in a wind park. Having detailed information about the repair time distribution may influence the results of maintenance modeling and might help identify cost factors.
Hamdi, Naser; Oweis, Rami; Abu Zraiq, Hamzeh; Abu Sammour, Denis
2012-04-01
The effective maintenance management of medical technology influences the quality of care delivered and the profitability of healthcare facilities. Medical equipment maintenance in Jordan lacks an objective prioritization system; consequently, the system is not sensitive to the impact of equipment downtime on patient morbidity and mortality. The current work presents a novel software system (EQUIMEDCOMP) that is designed to achieve valuable improvements in the maintenance management of medical technology. This work-order prioritization model sorts medical maintenance requests by calculating a priority index for each request. Model performance was assessed by utilizing maintenance requests from several Jordanian hospitals. The system proved highly efficient in minimizing equipment downtime based on healthcare delivery capacity, and, consequently, patient outcome. Additionally, a preventive maintenance optimization module and an equipment quality control system are incorporated. The system is, therefore, expected to improve the reliability of medical equipment and significantly improve safety and cost-efficiency.
NASA Astrophysics Data System (ADS)
Vahdani, Behnam; Jolai, Fariborz; Tavakkoli-Moghaddam, Reza; Meysam Mousavi, S.
2012-07-01
Maintenance outsourcing can be regarded as a strategic weapon to increase productivity and customer satisfaction in many companies, and this critical activity can be performed in a more efficient and effective way. This article presents two novel fuzzy possibilistic bi-objective zero-one programming (FPBOZOP) models for outsourcing of the equipment maintenance. In these models, cost parameters, including outsourcing cost, risk cost, time operations for performing the equipment maintenance and reliability level, as well as other influential parameters are considered through the outsourcing process. Moreover, the presented models can measure the capability of the company in doing different activities, unlike previous studies, in order to see the possibility of maintenance in-house, and can lead to make a best decision on the basis of the models' results. Both models are developed under uncertainty, which bring top managers the possibility of assigning more than one equipment or project to the supplier so that the profit is maximized, and the cost is minimized by considering bi-objectives concurrently. Then, a new fuzzy mathematical programming based possibilistic approach is introduced as a solution methodology from the recent literature to solve the proposed bi-objective zero-one programming (BOZOP) models and to reach a preferred compromise solution. Furthermore, a real-case study is utilized to demonstrate and to validate the effectiveness of the presented models. The computational results revealed that the models can be implemented in variety of problems in the domain of the equipment maintenance outsourcing and project outsourcing either from theory or application perspectives.
Cost Analysis for Large Civil Transport Rotorcraft
NASA Technical Reports Server (NTRS)
Coy, John J.
2006-01-01
This paper presents cost analysis of purchase price and DOC+I (direct operating cost plus interest) that supports NASA s study of three advanced rotorcraft concepts that could enter commercial transport service within 10 to 15 years. The components of DOC+I are maintenance, flight crew, fuel, depreciation, insurance, and finance. The cost analysis aims at VTOL (vertical takeoff and landing) and CTOL (conventional takeoff and landing) aircraft suitable for regional transport service. The resulting spreadsheet-implemented cost models are semi-empirical and based on Department of Transportation and Army data from actual operations of such aircraft. This paper describes a rationale for selecting cost tech factors without which VTOL is more costly than CTOL by a factor of 10 for maintenance cost and a factor of two for purchase price. The three VTOL designs selected for cost comparisons meet the mission requirement to fly 1,200 nautical miles at 350 knots and 30,000 ft carrying 120 passengers. The lowest cost VTOL design is a large civil tilt rotor (LCTR) aircraft. With cost tech factors applied, the LCTR is reasonably competitive with the Boeing 737-700 when operated in economy regional service following the business model of the selected baseline operation, that of Southwest Airlines.
Paranal maintenance and CMMS experience
NASA Astrophysics Data System (ADS)
Montano, Nelson
2004-10-01
During the last four years of operations, low technical downtime has been one of the relevant records of the Paranal Observatory. From the beginning of the Very Large Telescope (VLT) project, European Southern Observatory (ESO) has considered the implementation of a proper maintenance strategy a fundamental point in order to ensure low technical down time and preserve the Observatory's assets. The implementation of the maintenance strategy was based on the following aspects: - Strong maintenance sense during the design stage. Line Replacement Unit (LRU) concept, standardization and modularity of the Observatory equipment - Creation of a dedicated team for Maintenance - The implementation of a Computerized Maintenance Management System After four operational years, the result of these aspects has exceeded the expectations; the Observatory has been operating with high availability under a sustainable strategy. The strengths of the maintenance strategy have been based on modern maintenance concepts applied by regular production companies, where any minute of down time involves high cost. The operation of the actual Paranal Maintenance System is based mainly on proactive activities, such as regular inspections, preventive maintenance (PM) and predictive maintenance (PdM) plans. Nevertheless, it has been necessary to implement a strong plan for corrective maintenance (CM). The Spare Parts Strategy has also been an important point linked to the Maintenance Strategy and CMMS implementation. At present, almost 4,000 items related to the Observatory spare parts are loaded into the CMMS database. Currently, we are studying the implementation of a Reliability Centered Maintenance (RCM) project in one of our critical systems The following document presents the actual status of the Paranal Maintenance Strategy and which have been the motivations to implement the established strategy.
AN OPTIMAL MAINTENANCE MANAGEMENT MODEL FOR AIRPORT CONCRETE PAVEMENT
NASA Astrophysics Data System (ADS)
Shimomura, Taizo; Fujimori, Yuji; Kaito, Kiyoyuki; Obama, Kengo; Kobayashi, Kiyoshi
In this paper, an optimal management model is formulated for the performance-based rehabilitation/maintenance contract for airport concrete pavement, whereby two types of life cycle cost risks, i.e., ground consolidation risk and concrete depreciation risk, are explicitly considered. The non-homogenous Markov chain model is formulated to represent the deterioration processes of concrete pavement which are conditional upon the ground consolidation processes. The optimal non-homogenous Markov decision model with multiple types of risk is presented to design the optimal rehabilitation/maintenance plans. And the methodology to revise the optimal rehabilitation/maintenance plans based upon the monitoring data by the Bayesian up-to-dating rules. The validity of the methodology presented in this paper is examined based upon the case studies carried out for the H airport.
A Guide to the Management and Maintenance of School Grounds.
ERIC Educational Resources Information Center
Wood, Joan; Littlewood, Michael
This guidebook helps schools identify their maintenance requirements, choose the best organizational model of maintenance to ensure they receive a good quality service for their money, and help teachers and administrators achieve whole school awareness and commitment to school maintenance management. Sections address evaluating a school's…
Application of model predictive control for optimal operation of wind turbines
NASA Astrophysics Data System (ADS)
Yuan, Yuan; Cao, Pei; Tang, J.
2017-04-01
For large-scale wind turbines, reducing maintenance cost is a major challenge. Model predictive control (MPC) is a promising approach to deal with multiple conflicting objectives using the weighed sum approach. In this research, model predictive control method is applied to wind turbine to find an optimal balance between multiple objectives, such as the energy capture, loads on turbine components, and the pitch actuator usage. The actuator constraints are integrated into the objective function at the control design stage. The analysis is carried out in both the partial load region and full load region, and the performances are compared with those of a baseline gain scheduling PID controller. The application of this strategy achieves enhanced balance of component loads, the average power and actuator usages in partial load region.
Leyton, Marta; Batista, Marco; Lobato, Susana; Aspano, Mª Isabel; Jiménez, Ruth
2017-10-01
The objective of this study was to analyse the effectiveness of two intervention programs: a physical exercise program with strategies to support the three basic psychological needs (autonomy, competence and relatedness); and a physical exercise program with nutritional education in order to improve the lifestyles of adult and elderly women who practiced functional maintenance. The Self-Determination Theory was applied as the theoretical framework. A sample of 135 women aged between 40 and 88 years (59.66 ± 10.76) who enrolled in a 12-week functional maintenance program and attended 24 exercise classes took part in the study. A quasi-experimental study was performed where strategies to support the three basic psychological needs were applied to one group and strategies for the improvement of eating habits were applied to the other group. No strategy was applied to the control group. The main results showed an improvement in experimental groups I and II when compared to the control group regarding the variables of autonomy, competence, intrinsic regulation, identified regulation, introjected regulation, external regulation and eating habits, after the application of the intervention programs. The conclusion is that both intervention programs were successful with this project's participants and that it is crucial to promote such intervention programs in functional maintenance classes, as they foster healthy lifestyles among participants.
Study of the impact of automation on productivity in bus-maintenance facilities. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sumanth, D.J.; Weiss, H.J.; Adya, B.
1988-12-01
Whether or not the various types of automation and new technologies introduced in a bus-transit system really have an impact on productivity is the question addressed in the study. The report describes a new procedure of productivity measurement and evaluation for a county-transit system and provides an objective perspective on the impact of automation on productivity in bus maintenance facilities. The research objectives were: to study the impact of automation on total productivity in transit maintenance facilities; to develop and apply a methodology for measuring the total productivity of a Floridian transit maintenance facility (Bradenton-Manatee County bus maintenance facility whichmore » has been introducing automation since 1983); and to develop a practical step-by-step implementation scheme for the total productivity-based productivity measurement system that any bus manager can use. All 3 objectives were successfully accomplished.« less
NASA Astrophysics Data System (ADS)
Nasrum, A.; Pasaribu, U. S.; Husniah, H.
2016-02-01
This paper deals with maintenance service contract for a dump truck sold with a two-dimensional warranties. We consider a situation where an agent offers two maintenance contract options and the owner of the equipment has to select the optimal option either the OEM carried out all repairs and preventive maintenance activities (option one) or the OEM only carries out failure while the costumer undertakes preventive maintenance action in-house (option two). As the number of preventive maintenance and corrective maintenance that occurs in the area of servicing contracts is very influential in determining the value of the contract, we have to determine the optimal time between preventive maintenance that can minimize the cost of repair in the contract area. Moreover, we also study the maintenance service contract considering reduction of the intensity function after preventive maintenance from both the owner and OEM point of views. In this paper, we use a Weibull intensity function to consider a product with increasing failure intensity. We use a non-cooperative game formulation to determine the optimal price structure (i.e., the contract price and repair cost) for the OEM and the owner. A numerical example derived from the model has shown that if the owner choose option one then the owner obtain a higher profit compared with the profit resulted from option two. The result agree with earlier work which uses the accelerated failure time (AFT) for the failure modeling, while here we model the failure of the dump truck without the use of the AFT.
Daniels, Joseph; Farquhar, Carey; Nathanson, Neal; Mashalla, Yohana; Petracca, Frances; Desmond, Michelle; Green, Wendy; Davies, Luke; O'Malley, Gabrielle
2014-12-01
Training health professionals in leadership and management skills is a key component of health systems strengthening in low-resource settings. The importance of evaluating the effectiveness of these programs has received increased attention over the past several years, although such evaluations continue to pose significant challenges. This article presents evaluation data from the pilot year of the Afya Bora Fellowship, an African-based training program to increase the leadership capacity of health professionals. Firstly, we describe the goals of the Afya Bora Fellowship. Then, we present an adaptation of the transtheoretical model for behavior change called the Health Leadership Development Model, as an analytical lens to identify and describe evidence of individual leadership behavior change among training participants during and shortly after the pilot year of the program. The Health Leadership Development Model includes the following: pre-contemplation (status quo), contemplation (testing and internalizing leadership), preparation - (moving toward leadership), action (leadership in action), and maintenance (effecting organizational change). We used data from surveys, in-depth interviews, journal entries and course evaluations as data points to populate the Health Leadership Development Model. In the short term, fellows demonstrated increased leadership development during and shortly after the intervention and reflected the contemplation, preparation and action stages of the Health Leadership Development Model. However, expanded interventions and/or additional time may be needed to support behavior change toward the maintenance stages. We conclude that the Health Leadership Development Model is useful for informing health leadership training design and evaluation to contribute to sustainable health organizational change. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Kumar, Girish; Jain, Vipul; Gandhi, O. P.
2018-03-01
Maintenance helps to extend equipment life by improving its condition and avoiding catastrophic failures. Appropriate model or mechanism is, thus, needed to quantify system availability vis-a-vis a given maintenance strategy, which will assist in decision-making for optimal utilization of maintenance resources. This paper deals with semi-Markov process (SMP) modeling for steady state availability analysis of mechanical systems that follow condition-based maintenance (CBM) and evaluation of optimal condition monitoring interval. The developed SMP model is solved using two-stage analytical approach for steady-state availability analysis of the system. Also, CBM interval is decided for maximizing system availability using Genetic Algorithm approach. The main contribution of the paper is in the form of a predictive tool for system availability that will help in deciding the optimum CBM policy. The proposed methodology is demonstrated for a centrifugal pump.
Optimal manpower allocation in aircraft line maintenance (Case in GMF AeroAsia)
NASA Astrophysics Data System (ADS)
Puteri, V. E.; Yuniaristanto, Hisjam, M.
2017-11-01
This paper presents a mathematical modeling to find the optimal manpower allocation in an aircraft line maintenance. This research focuses on assigning the number and type of manpower that allocated to each service. This study considers the licenced worker or Aircraft Maintenance Engineer Licence (AMEL) and non licenced worker or Aircraft Maintenance Technician (AMT). In this paper, we also consider the relationship of each station in terms of the possibility to transfer the manpower among them. The optimization model considers the number of manpowers needed for each service and the requirement of AMEL worker. This paper aims to determine the optimal manpower allocation using the mathematical modeling. The objective function of the model is to find the minimum employee expenses. The model was solved using the ILOG CPLEX software. The results show that the manpower allocation can meet the manpower need and the all load can be served.
Application of the Delphi technique in healthcare maintenance.
Njuangang, Stanley; Liyanage, Champika; Akintoye, Akintola
2017-10-09
Purpose The purpose of this paper is to examine the research design, issues and considerations in the application of the Delphi technique to identify, refine and rate the critical success factors and performance measures in maintenance-associated infections. Design/methodology/approach In-depth literature review through the application of open and axial coding were applied to formulate the interview and research questions. These were used to conduct an exploratory case study of two healthcare maintenance managers, randomly selected from two National Health Service Foundation Trusts in England. The results of exploratory case study provided the rationale for the application of the Delphi technique in this research. The different processes in the application of the Delphi technique in healthcare research are examined thoroughly. Findings This research demonstrates the need to apply and integrate different research methods to enhance the validity of the Delphi technique. The rationale for the application of the Delphi technique in this research is because some healthcare maintenance managers lack knowledge about basic infection control (IC) principles to make hospitals safe for patient care. The result of first round of the Delphi exercise is a useful contribution in its own rights. It identified a number of salient issues and differences in the opinions of the Delphi participants, noticeably between healthcare maintenance managers and members of the infection control team. It also resulted in useful suggestions and comments to improve the quality and presentation of the second- and third-round Delphi instruments. Practical implications This research provides a research methodology that can be adopted by researchers investigating new and emerging issues in the healthcare sector. As this research demonstrates, the Delphi technique is relevant in soliciting expert knowledge and opinion to identify performance measures to control maintenance-associated infections in hospitals. The methodology provided here could be applied by other researchers elsewhere to probe, investigate and generate rich information about new and emerging healthcare research topics. Originality/value The authors demonstrate how different research methods can be integrated to enhance the validity of the Delphi technique. For example, the results of an exploratory case study provided the rationale for the application of the Delphi technique investigating the key performance measures in maintenance-associated infections. The different processes involved in the application of the Delphi technique are also carefully explored and discussed in depth.
NASA Astrophysics Data System (ADS)
Koon, Phillip L.; Greene, Scott
2002-07-01
Our aerospace customers are demanding that we drastically reduce the cost of operating and supporting our products. Our space customer in particular is looking for the next generation of reusable launch vehicle systems to support more aircraft like operation. To achieve this goal requires more than an evolution in materials, processes and systems, what is required is a paradigm shift in the design of the launch vehicles and the processing systems that support the launch vehicles. This paper describes the Automated Informed Maintenance System (AIM) we are developing for NASA's Space Launch Initiative (SLI) Second Generation Reusable Launch Vehicle (RLV). Our system includes an Integrated Health Management (IHM) system for the launch vehicles and ground support systems, which features model based diagnostics and prognostics. Health Management data is used by our AIM decision support and process aids to automatically plan maintenance, generate work orders and schedule maintenance activities along with the resources required to execute these processes. Our system will automate the ground processing for a spaceport handling multiple RLVs executing multiple missions. To accomplish this task we are applying the latest web based distributed computing technologies and application development techniques.
A multi-period optimization model for energy planning with CO(2) emission consideration.
Mirzaesmaeeli, H; Elkamel, A; Douglas, P L; Croiset, E; Gupta, M
2010-05-01
A novel deterministic multi-period mixed-integer linear programming (MILP) model for the power generation planning of electric systems is described and evaluated in this paper. The model is developed with the objective of determining the optimal mix of energy supply sources and pollutant mitigation options that meet a specified electricity demand and CO(2) emission targets at minimum cost. Several time-dependent parameters are included in the model formulation; they include forecasted energy demand, fuel price variability, construction lead time, conservation initiatives, and increase in fixed operational and maintenance costs over time. The developed model is applied to two case studies. The objective of the case studies is to examine the economical, structural, and environmental effects that would result if the electricity sector was required to reduce its CO(2) emissions to a specified limit. Copyright 2009 Elsevier Ltd. All rights reserved.
Building information modelling review with potential applications in tunnel engineering of China.
Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin
2017-08-01
Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.
Building information modelling review with potential applications in tunnel engineering of China
Zhou, Weihong; Qin, Haiyang; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin
2017-01-01
Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance. PMID:28878970
Building information modelling review with potential applications in tunnel engineering of China
NASA Astrophysics Data System (ADS)
Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin
2017-08-01
Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.
Fatigue Solutions for Maintenance: From Science to Workplace Reality
2011-12-01
John Hall IAMAW Jim Hein AWP-204 William (Bill) Johnson AIR-100 Charles (Bob) Kelley AJW-341 Daniel Mollicone Pulsar Informatics, Inc. Thomas...That Fit Industry. Dr. Daniel Mollicone, President and Chief Executive Officer for Pulsar Informatics, Inc., presented research on the use of...FAA Maintenance Fatigue applied R&D program has worked with Pulsar Informatics to develop a software system that helps individuals assess their
34 CFR 403.184 - How does a State request a waiver of the maintenance of effort requirement?
Code of Federal Regulations, 2010 CFR
2010-07-01
... APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403.184 How does... 34 Education 3 2010-07-01 2010-07-01 false How does a State request a waiver of the maintenance of effort requirement? 403.184 Section 403.184 Education Regulations of the Offices of the Department of...
34 CFR 403.184 - How does a State request a waiver of the maintenance of effort requirement?
Code of Federal Regulations, 2013 CFR
2013-07-01
... APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403.184 How does... 34 Education 3 2013-07-01 2013-07-01 false How does a State request a waiver of the maintenance of effort requirement? 403.184 Section 403.184 Education Regulations of the Offices of the Department of...
34 CFR 403.184 - How does a State request a waiver of the maintenance of effort requirement?
Code of Federal Regulations, 2014 CFR
2014-07-01
... APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403.184 How does... 34 Education 3 2014-07-01 2014-07-01 false How does a State request a waiver of the maintenance of effort requirement? 403.184 Section 403.184 Education Regulations of the Offices of the Department of...
34 CFR 403.184 - How does a State request a waiver of the maintenance of effort requirement?
Code of Federal Regulations, 2012 CFR
2012-07-01
... APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403.184 How does... 34 Education 3 2012-07-01 2012-07-01 false How does a State request a waiver of the maintenance of effort requirement? 403.184 Section 403.184 Education Regulations of the Offices of the Department of...
34 CFR 403.184 - How does a State request a waiver of the maintenance of effort requirement?
Code of Federal Regulations, 2011 CFR
2011-07-01
... APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403.184 How does... 34 Education 3 2011-07-01 2011-07-01 false How does a State request a waiver of the maintenance of effort requirement? 403.184 Section 403.184 Education Regulations of the Offices of the Department of...
Code of Federal Regulations, 2014 CFR
2014-10-01
... for private maintenance of more than 4 wild horses or burros. 4750.3-3 Section 4750.3-3 Public Lands... INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS... than 4 wild horses or burros. (a) An individual applying to adopt more than 4 wild horses or burros...
Code of Federal Regulations, 2011 CFR
2011-10-01
... for private maintenance of more than 4 wild horses or burros. 4750.3-3 Section 4750.3-3 Public Lands... INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS... than 4 wild horses or burros. (a) An individual applying to adopt more than 4 wild horses or burros...
Code of Federal Regulations, 2012 CFR
2012-10-01
... for private maintenance of more than 4 wild horses or burros. 4750.3-3 Section 4750.3-3 Public Lands... INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS... than 4 wild horses or burros. (a) An individual applying to adopt more than 4 wild horses or burros...
Code of Federal Regulations, 2013 CFR
2013-10-01
... for private maintenance of more than 4 wild horses or burros. 4750.3-3 Section 4750.3-3 Public Lands... INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS... than 4 wild horses or burros. (a) An individual applying to adopt more than 4 wild horses or burros...
34 CFR 403.185 - How does the Secretary compute maintenance of effort in the event of a waiver?
Code of Federal Regulations, 2010 CFR
2010-07-01
... VOCATIONAL AND APPLIED TECHNOLOGY EDUCATION PROGRAM What Financial Conditions Must Be Met by a State? § 403... 34 Education 3 2010-07-01 2010-07-01 false How does the Secretary compute maintenance of effort in the event of a waiver? 403.185 Section 403.185 Education Regulations of the Offices of the Department...
Johnston, A.S.A.; Hodson, M.E.; Thorbek, P.; Alvarez, T.; Sibly, R.M.
2014-01-01
Earthworms are important organisms in soil communities and so are used as model organisms in environmental risk assessments of chemicals. However current risk assessments of soil invertebrates are based on short-term laboratory studies, of limited ecological relevance, supplemented if necessary by site-specific field trials, which sometimes are challenging to apply across the whole agricultural landscape. Here, we investigate whether population responses to environmental stressors and pesticide exposure can be accurately predicted by combining energy budget and agent-based models (ABMs), based on knowledge of how individuals respond to their local circumstances. A simple energy budget model was implemented within each earthworm Eisenia fetida in the ABM, based on a priori parameter estimates. From broadly accepted physiological principles, simple algorithms specify how energy acquisition and expenditure drive life cycle processes. Each individual allocates energy between maintenance, growth and/or reproduction under varying conditions of food density, soil temperature and soil moisture. When simulating published experiments, good model fits were obtained to experimental data on individual growth, reproduction and starvation. Using the energy budget model as a platform we developed methods to identify which of the physiological parameters in the energy budget model (rates of ingestion, maintenance, growth or reproduction) are primarily affected by pesticide applications, producing four hypotheses about how toxicity acts. We tested these hypotheses by comparing model outputs with published toxicity data on the effects of copper oxychloride and chlorpyrifos on E. fetida. Both growth and reproduction were directly affected in experiments in which sufficient food was provided, whilst maintenance was targeted under food limitation. Although we only incorporate toxic effects at the individual level we show how ABMs can readily extrapolate to larger scales by providing good model fits to field population data. The ability of the presented model to fit the available field and laboratory data for E. fetida demonstrates the promise of the agent-based approach in ecology, by showing how biological knowledge can be used to make ecological inferences. Further work is required to extend the approach to populations of more ecologically relevant species studied at the field scale. Such a model could help extrapolate from laboratory to field conditions and from one set of field conditions to another or from species to species. PMID:25844009
Fleet equipment performance measure preventive maintenance model.
DOT National Transportation Integrated Search
2013-02-28
The Texas Department of Transportation : (TxDOT) operates a large fleet of on-road and : off-road equipment. Consequently, fleet : maintenance procedures (specifically preventive : maintenance such as oil changes) represent a : significant cost to th...
Elements of a Green Infrastructure Maintenance Business Plan for Milwaukee WI
This report reflects the feedback provided by MMSD and local stakeholders about different business models for conducting maintenance. The findings from this process will inform a maintenance plan for the region.
[Applying the clustering technique for characterising maintenance outsourcing].
Cruz, Antonio M; Usaquén-Perilla, Sandra P; Vanegas-Pabón, Nidia N; Lopera, Carolina
2010-06-01
Using clustering techniques for characterising companies providing health institutions with maintenance services. The study analysed seven pilot areas' equipment inventory (264 medical devices). Clustering techniques were applied using 26 variables. Response time (RT), operation duration (OD), availability and turnaround time (TAT) were amongst the most significant ones. Average biomedical equipment obsolescence value was 0.78. Four service provider clusters were identified: clusters 1 and 3 had better performance, lower TAT, RT and DR values (56 % of the providers coded O, L, C, B, I, S, H, F and G, had 1 to 4 day TAT values:
Nelson, Richard E; Angelovic, Aaron W; Nelson, Scott D; Gleed, Jeremy R; Drews, Frank A
2015-05-01
Adherence engineering applies human factors principles to examine non-adherence within a specific task and to guide the development of materials or equipment to increase protocol adherence and reduce human error. Central line maintenance (CLM) for intensive care unit (ICU) patients is a task through which error or non-adherence to protocols can cause central line-associated bloodstream infections (CLABSIs). We conducted an economic analysis of an adherence engineering CLM kit designed to improve the CLM task and reduce the risk of CLABSI. We constructed a Markov model to compare the cost-effectiveness of the CLM kit, which contains each of the 27 items necessary for performing the CLM procedure, compared with the standard care procedure for CLM, in which each item for dressing maintenance is gathered separately. We estimated the model using the cost of CLABSI overall ($45,685) as well as the excess LOS (6.9 excess ICU days, 3.5 excess general ward days). Assuming the CLM kit reduces the risk of CLABSI by 100% and 50%, this strategy was less costly (cost savings between $306 and $860) and more effective (between 0.05 and 0.13 more quality-adjusted life-years) compared with not using the pre-packaged kit. We identified threshold values for the effectiveness of the kit in reducing CLABSI for which the kit strategy was no longer less costly. An adherence engineering-based intervention to streamline the CLM process can improve patient outcomes and lower costs. Patient safety can be improved by adopting new approaches that are based on human factors principles.
In Vivo Control of CpG and Non-CpG DNA Methylation by DNA Methyltransferases
Arand, Julia; Spieler, David; Karius, Tommy; Branco, Miguel R.; Meilinger, Daniela; Meissner, Alexander; Jenuwein, Thomas; Xu, Guoliang; Leonhardt, Heinrich; Wolf, Verena; Walter, Jörn
2012-01-01
The enzymatic control of the setting and maintenance of symmetric and non-symmetric DNA methylation patterns in a particular genome context is not well understood. Here, we describe a comprehensive analysis of DNA methylation patterns generated by high resolution sequencing of hairpin-bisulfite amplicons of selected single copy genes and repetitive elements (LINE1, B1, IAP-LTR-retrotransposons, and major satellites). The analysis unambiguously identifies a substantial amount of regional incomplete methylation maintenance, i.e. hemimethylated CpG positions, with variant degrees among cell types. Moreover, non-CpG cytosine methylation is confined to ESCs and exclusively catalysed by Dnmt3a and Dnmt3b. This sequence position–, cell type–, and region-dependent non-CpG methylation is strongly linked to neighboring CpG methylation and requires the presence of Dnmt3L. The generation of a comprehensive data set of 146,000 CpG dyads was used to apply and develop parameter estimated hidden Markov models (HMM) to calculate the relative contribution of DNA methyltransferases (Dnmts) for de novo and maintenance DNA methylation. The comparative modelling included wild-type ESCs and mutant ESCs deficient for Dnmt1, Dnmt3a, Dnmt3b, or Dnmt3a/3b, respectively. The HMM analysis identifies a considerable de novo methylation activity for Dnmt1 at certain repetitive elements and single copy sequences. Dnmt3a and Dnmt3b contribute de novo function. However, both enzymes are also essential to maintain symmetrical CpG methylation at distinct repetitive and single copy sequences in ESCs. PMID:22761581
Augmented reality application utility for aviation maintenance work instruction
NASA Astrophysics Data System (ADS)
Pourcho, John Bryan
Current aviation maintenance work instructions do not display information effectively enough to prevent costly errors and safety concerns. Aircraft are complex assemblies of highly interrelated components that confound troubleshooting and can make the maintenance procedure difficult (Drury & Gramopadhye, 2001). The sophisticated nature of aircraft maintenance necessitates a revolutionized training intervention for aviation maintenance technicians (United States General Accounting Office, 2003). Quite simply, the paper based job task cards fall short of offering rapid access to technical data and the system or component visualization necessary for working on complex integrated aircraft systems. Possible solutions to this problem include upgraded standards for paper based task cards and the use of integrated 3D product definition used on various mobile platforms (Ropp, Thomas, Lee, Broyles, Lewin, Andreychek, & Nicol, 2013). Previous studies have shown that incorporation of 3D graphics in work instructions allow the user to more efficiently and accurately interpret maintenance information (Jackson & Batstone, 2008). For aircraft maintenance workers, the use of mobile 3D model-based task cards could make current paper task card standards obsolete with their ability to deliver relevant, synchronized information to and from the hangar. Unlike previous versions of 3D model-based definition task cards and paper task cards, which are currently used in the maintenance industry, 3D model based definition task cards have the potential to be more mobile and accessible. Utilizing augmented reality applications on mobile devices to seamlessly deliver 3D product definition on mobile devices could increase the efficiency, accuracy, and reduce the mental workload for technicians when performing maintenance tasks (Macchiarella, 2004). This proposal will serve as a literary review of the aviation maintenance industry, the spatial ability of maintenance technicians, and benefits of modern digital hardware to educate, point out gaps in research, and observe possible foundations on which to build the future of aviation maintenance job task cards leading to a the methodology of the proposed study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Y.A.; Feltus, M.A.
1995-07-01
Reliability-centered maintenance (RCM) methods are applied to boiling water reactor plant-specific emergency core cooling system probabilistic risk assessment (PRA) fault trees. The RCM is a technique that is system function-based, for improving a preventive maintenance (PM) program, which is applied on a component basis. Many PM programs are based on time-directed maintenance tasks, while RCM methods focus on component condition-directed maintenance tasks. Stroke time test data for motor-operated valves (MOVs) are used to address three aspects concerning RCM: (a) to determine if MOV stroke time testing was useful as a condition-directed PM task; (b) to determine and compare the plant-specificmore » MOV failure data from a broad RCM philosophy time period compared with a PM period and, also, compared with generic industry MOV failure data; and (c) to determine the effects and impact of the plant-specific MOV failure data on core damage frequency (CDF) and system unavailabilities for these emergency systems. The MOV stroke time test data from four emergency core cooling systems [i.e., high-pressure coolant injection (HPCI), reactor core isolation cooling (RCIC), low-pressure core spray (LPCS), and residual heat removal/low-pressure coolant injection (RHR/LPCI)] were gathered from Philadelphia Electric Company`s Peach Bottom Atomic Power Station Units 2 and 3 between 1980 and 1992. The analyses showed that MOV stroke time testing was not a predictor for eminent failure and should be considered as a go/no-go test. The failure data from the broad RCM philosophy showed an improvement compared with the PM-period failure rates in the emergency core cooling system MOVs. Also, the plant-specific MOV failure rates for both maintenance philosophies were shown to be lower than the generic industry estimates.« less
Development of a Knowledge-Based System Approach for Decision Making in Construction Projects
1992-05-01
a generic model for an administrative facility and medical facility with predefined fixed building systems based on Air Force criteria and past...MAINTENANCE HANGAR (MEDIUM BAY) CORROSION CONTROL HANGAR (HIGH BAY) FUEL SYSTEM MAINTENANCE HANGAR (MEDIUM BAY) MEDICAL MODEL 82 Table 5-1--continued...BUILDING SUPPORT MEDICAL LOGISTICS MEDICAL TOTAL 85 Table 5-2--continued MISSILE ASSEMBLY AND MAINTENANCE BUILDING TOTAL MISSILE LOADING AND UNLOADING
User's Guide for a Computerized Track Maintenance Simulation Cost Methodology
DOT National Transportation Integrated Search
1982-02-01
This User's Guide describes the simulation cost modeling technique developed for costing of maintenance operations of track and its component structures. The procedure discussed provides for separate maintenance cost entries to be associated with def...
This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.
Advancements in Risk-Informed Performance-Based Asset Management for Commercial Nuclear Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liming, James K.; Ravindra, Mayasandra K.
2006-07-01
Over the past several years, ABSG Consulting Inc. (ABS Consulting) and the South Texas Project Nuclear Operating Company (STPNOC) have developed a decision support process and associated software for risk-informed, performance-based asset management (RIPBAM) of nuclear power plant facilities. RIPBAM applies probabilistic risk assessment (PRA) tools and techniques in the realm of plant physical and financial asset management. The RIPBAM process applies a tiered set of models and supporting performance measures (or metrics) that can ultimately be applied to support decisions affecting the allocation and management of plant resources (e.g., funding, staffing, scheduling, etc.). In general, the ultimate goal ofmore » the RIPBAM process is to continually support decision-making to maximize a facility's net present value (NPV) and long-term profitability for its owners. While the initial applications of RIPBAM have been for nuclear power stations, the methodology can easily be adapted to other types of power station or complex facility decision-making support. RIPBAM can also be designed to focus on performance metrics other than NPV and profitability (e.g., mission reliability, operational availability, probability of mission success per dollar invested, etc.). Recent advancements in the RIPBAM process focus on expanding the scope of previous RIPBAM applications to include not only operations, maintenance, and safety issues, but also broader risk perception components affecting plant owner (stockholder), operator, and regulator biases. Conceptually, RIPBAM is a comprehensive risk-informed cash flow model for decision support. It originated as a tool to help manage plant refueling outage scheduling, and was later expanded to include the full spectrum of operations and maintenance decision support. However, it differs from conventional business modeling tools in that it employs a systems engineering approach with broadly based probabilistic analysis of organizational 'value streams'. The scope of value stream inclusion in the process can be established by the user, but in its broadest applications, RIPBAM can be used to address how risk perceptions of plant owners and regulators are impacted by plant performance. Plant staffs can expand and refine RIPBAM models scope via a phased program of activities over time. This paper shows how the multi-metric uncertainty analysis feature of RIPBAM can apply a wide spectrum of decision-influencing factors to support decisions designed to maximize the probability of achieving, maintaining, and improving upon plant goals and objectives. In this paper, the authors show how this approach can be extremely valuable to plant owners and operators in supporting plant value-impacting decision-making processes. (authors)« less
Multi-objective decision-making model based on CBM for an aircraft fleet
NASA Astrophysics Data System (ADS)
Luo, Bin; Lin, Lin
2018-04-01
Modern production management patterns, in which multi-unit (e.g., a fleet of aircrafts) are managed in a holistic manner, have brought new challenges for multi-unit maintenance decision making. To schedule a good maintenance plan, not only does the individual machine maintenance have to be considered, but also the maintenance of the other individuals have to be taken into account. Since most condition-based maintenance researches for aircraft focused on solely reducing maintenance cost or maximizing the availability of single aircraft, as well as considering that seldom researches concentrated on both the two objectives: minimizing cost and maximizing the availability of a fleet (total number of available aircraft in fleet), a multi-objective decision-making model based on condition-based maintenance concentrated both on the above two objectives is established. Furthermore, in consideration of the decision maker may prefer providing the final optimal result in the form of discrete intervals instead of a set of points (non-dominated solutions) in real decision-making problem, a novel multi-objective optimization method based on support vector regression is proposed to solve the above multi-objective decision-making model. Finally, a case study regarding a fleet is conducted, with the results proving that the approach efficiently generates outcomes that meet the schedule requirements.
Building an experience factory for maintenance
NASA Technical Reports Server (NTRS)
Valett, Jon D.; Condon, Steven E.; Briand, Lionel; Kim, Yong-Mi; Basili, Victor R.
1994-01-01
This paper reports the preliminary results of a study of the software maintenance process in the Flight Dynamics Division (FDD) of the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC). This study is being conducted by the Software Engineering Laboratory (SEL), a research organization sponsored by the Software Engineering Branch of the FDD, which investigates the effectiveness of software engineering technologies when applied to the development of applications software. This software maintenance study began in October 1993 and is being conducted using the Quality Improvement Paradigm (QIP), a process improvement strategy based on three iterative steps: understanding, assessing, and packaging. The preliminary results represent the outcome of the understanding phase, during which SEL researchers characterized the maintenance environment, product, and process. Findings indicate that a combination of quantitative and qualitative analysis is effective for studying the software maintenance process, that additional measures should be collected for maintenance (as opposed to new development), and that characteristics such as effort, error rate, and productivity are best considered on a 'release' basis rather than on a project basis. The research thus far has documented some basic differences between new development and software maintenance. It lays the foundation for further application of the QIP to investigate means of improving the maintenance process and product in the FDD.
A GIS-based Model for Natural Gas Data Conversion
NASA Astrophysics Data System (ADS)
Bitik, E.; Seker, D. Z.; Denli, H. H.
2014-12-01
In Turkey gas utility sector has undergone major changes in terms of increased competition between gas providers, efforts in improving services, and applying new technological solutions. This paper discusses the challenges met by gas companies to switch from long workflows of gas distribution, sales and maintenance into IT driven efficient management of complex information both spatially and non-spatially. The aim of this study is migration of all gas data and information into a GIS environment in order to manage and operate all infrastructure investments with a Utility Management System. All data conversion model for migration was designed and tested during the study. A flowchart is formed to transfer the old data layers to the new structure based on geodatabase.
An XML-Based Manipulation and Query Language for Rule-Based Information
NASA Astrophysics Data System (ADS)
Mansour, Essam; Höpfner, Hagen
Rules are utilized to assist in the monitoring process that is required in activities, such as disease management and customer relationship management. These rules are specified according to the application best practices. Most of research efforts emphasize on the specification and execution of these rules. Few research efforts focus on managing these rules as one object that has a management life-cycle. This paper presents our manipulation and query language that is developed to facilitate the maintenance of this object during its life-cycle and to query the information contained in this object. This language is based on an XML-based model. Furthermore, we evaluate the model and language using a prototype system applied to a clinical case study.
Maintenance of equilibrium point control during an unexpectedly loaded rapid limb movement.
Simmons, R W; Richardson, C
1984-06-08
Two experiments investigated whether the equilibrium point hypothesis or the mass-spring model of motor control subserves positioning accuracy during spring loaded, rapid, bi-articulated movement. For intact preparations, the equilibrium point hypothesis predicts response accuracy to be determined by a mixture of afferent and efferent information, whereas the mass-spring model predicts positioning to be under a direct control system. Subjects completed a series of load-resisted training trials to a spatial target. The magnitude of a sustained spring load was unexpectedly increased on selected trials. Results indicated positioning accuracy and applied force varied with increases in load, which suggests that the original efferent commands are modified by afferent information during the movement as predicted by the equilibrium point hypothesis.
Modelling operations and security of cloud systems using Z-notation and Chinese Wall security policy
NASA Astrophysics Data System (ADS)
Basu, Srijita; Sengupta, Anirban; Mazumdar, Chandan
2016-11-01
Enterprises are increasingly using cloud computing for hosting their applications. Availability of fast Internet and cheap bandwidth are causing greater number of people to use cloud-based services. This has the advantage of lower cost and minimum maintenance. However, ensuring security of user data and proper management of cloud infrastructure remain major areas of concern. Existing techniques are either too complex, or fail to properly represent the actual cloud scenario. This article presents a formal cloud model using the constructs of Z-notation. Principles of the Chinese Wall security policy have been applied to design secure cloud-specific operations. The proposed methodology will enable users to safely host their services, as well as process sensitive data, on cloud.
Challenges for Engineering Design, Construction, and Maintenance of Infrastructure in Afghanistan
2010-11-01
applied engineering expertise that collectively can solve challenging infra- structure problems. USACE-ERDC’s researchers and engineers are field...Development Center (ERDC) possesses a unique combination of basic research and applied engineering expertise that collectively can solve challenging...restoration, and other projects. The USACE Engineer Research and Development Center (ERDC) possesses a unique combination of basic research and applied
Qualitative Maintenance Experience Handbook. P-3C/S-3A Supplement.
1977-06-15
axle which automatically assists in disc alignment, a positive feature, in easing maintenance and preventing casual damage. Brake assemblies should...Reverse Of Removal Use brake tool to align brake discs . After Installation Actions: _ Bleed _ Rig _ Adjust X Service Lubricate - Boresight. _ Other...Hydraulic I Access Required: Test Equipment Required: Actions: 1. Check clearance of discs after brakes are put on. 2. Apply brakes . 8 ANALYST’S COMMENTS
Cirrus cloud model parameterizations: Incorporating realistic ice particle generation
NASA Technical Reports Server (NTRS)
Sassen, Kenneth; Dodd, G. C.; Starr, David OC.
1990-01-01
Recent cirrus cloud modeling studies have involved the application of a time-dependent, two dimensional Eulerian model, with generalized cloud microphysical parameterizations drawn from experimental findings. For computing the ice versus vapor phase changes, the ice mass content is linked to the maintenance of a relative humidity with respect to ice (RHI) of 105 percent; ice growth occurs both with regard to the introduction of new particles and the growth of existing particles. In a simplified cloud model designed to investigate the basic role of various physical processes in the growth and maintenance of cirrus clouds, these parametric relations are justifiable. In comparison, the one dimensional cloud microphysical model recently applied to evaluating the nucleation and growth of ice crystals in cirrus clouds explicitly treated populations of haze and cloud droplets, and ice crystals. Although these two modeling approaches are clearly incompatible, the goal of the present numerical study is to develop a parametric treatment of new ice particle generation, on the basis of detailed microphysical model findings, for incorporation into improved cirrus growth models. For example, the relation between temperature and the relative humidity required to generate ice crystals from ammonium sulfate haze droplets, whose probability of freezing through the homogeneous nucleation mode are a combined function of time and droplet molality, volume, and temperature. As an example of this approach, the results of cloud microphysical simulations are presented showing the rather narrow domain in the temperature/humidity field where new ice crystals can be generated. The microphysical simulations point out the need for detailed CCN studies at cirrus altitudes and haze droplet measurements within cirrus clouds, but also suggest that a relatively simple treatment of ice particle generation, which includes cloud chemistry, can be incorporated into cirrus cloud growth.
ERIC Educational Resources Information Center
Hekler, Eric B.; Buman, Matthew P.; Poothakandiyil, Nikhil; Rivera, Daniel E.; Dzierzewski, Joseph M.; Aiken Morgan, Adrienne; McCrae, Christina S.; Roberts, Beverly L.; Marsiske, Michael; Giacobbi, Peter R., Jr.
2013-01-01
Efficacious interventions to promote long-term maintenance of physical activity are not well understood. Engineers have developed methods to create dynamical system models for modeling idiographic (i.e., within-person) relationships within systems. In behavioral research, dynamical systems modeling may assist in decomposing intervention effects…
An Iterative Approach for the Optimization of Pavement Maintenance Management at the Network Level
Torres-Machí, Cristina; Chamorro, Alondra; Videla, Carlos; Yepes, Víctor
2014-01-01
Pavement maintenance is one of the major issues of public agencies. Insufficient investment or inefficient maintenance strategies lead to high economic expenses in the long term. Under budgetary restrictions, the optimal allocation of resources becomes a crucial aspect. Two traditional approaches (sequential and holistic) and four classes of optimization methods (selection based on ranking, mathematical optimization, near optimization, and other methods) have been applied to solve this problem. They vary in the number of alternatives considered and how the selection process is performed. Therefore, a previous understanding of the problem is mandatory to identify the most suitable approach and method for a particular network. This study aims to assist highway agencies, researchers, and practitioners on when and how to apply available methods based on a comparative analysis of the current state of the practice. Holistic approach tackles the problem considering the overall network condition, while the sequential approach is easier to implement and understand, but may lead to solutions far from optimal. Scenarios defining the suitability of these approaches are defined. Finally, an iterative approach gathering the advantages of traditional approaches is proposed and applied in a case study. The proposed approach considers the overall network condition in a simpler and more intuitive manner than the holistic approach. PMID:24741352
An iterative approach for the optimization of pavement maintenance management at the network level.
Torres-Machí, Cristina; Chamorro, Alondra; Videla, Carlos; Pellicer, Eugenio; Yepes, Víctor
2014-01-01
Pavement maintenance is one of the major issues of public agencies. Insufficient investment or inefficient maintenance strategies lead to high economic expenses in the long term. Under budgetary restrictions, the optimal allocation of resources becomes a crucial aspect. Two traditional approaches (sequential and holistic) and four classes of optimization methods (selection based on ranking, mathematical optimization, near optimization, and other methods) have been applied to solve this problem. They vary in the number of alternatives considered and how the selection process is performed. Therefore, a previous understanding of the problem is mandatory to identify the most suitable approach and method for a particular network. This study aims to assist highway agencies, researchers, and practitioners on when and how to apply available methods based on a comparative analysis of the current state of the practice. Holistic approach tackles the problem considering the overall network condition, while the sequential approach is easier to implement and understand, but may lead to solutions far from optimal. Scenarios defining the suitability of these approaches are defined. Finally, an iterative approach gathering the advantages of traditional approaches is proposed and applied in a case study. The proposed approach considers the overall network condition in a simpler and more intuitive manner than the holistic approach.
Application of Superconducting Power Cables to DC Electric Railway Systems
NASA Astrophysics Data System (ADS)
Ohsaki, Hiroyuki; Lv, Zhen; Sekino, Masaki; Tomita, Masaru
For novel design and efficient operation of next-generation DC electric railway systems, especially for their substantial energy saving, we have studied the feasibility of applying superconducting power cables to them. In this paper it is assumed that a superconducting power cable is applied to connect substations supplying electric power to trains. An analysis model line was described by an electric circuit, which was analyzed with MATLAB-Simulink. From the calculated voltages and currents of the circuit, the regenerative brake and the energy losses were estimated. In addition, assuming the heat loads of superconducting power cables and the cryogenic efficiency, the energy saving of the total system was evaluated. The results show that the introduction of superconducting power cables could achieve the improved use of regenerative brake, the loss reduction, the decreased number of substations, the reduced maintenance, etc.
POSSUM--a model for surgical outcome audit in quality care.
Ng, K J; Yii, M K
2003-10-01
Comparative surgical audit to monitor quality of care should be performed with a risk-adjusted scoring system rather than using crude morbidity and mortality rates. A validated and widely applied risk adjusted scoring system, P-POSSUM (Portsmouth-Physiological and Operative Severity Score for the enUmeration of Mortality) methodology, was applied to a prospective series of predominantly general surgical patients at the Sarawak General Hospital, Kuching over a six months period. The patients were grouped into four risk groups. The observed mortality rates were not significantly different from predicted rates, showing that the quality of surgical care was at par with typical western series. The simplicity and advantages of this scoring system over other auditing tools are discussed. The P-POSSUM methodology could form the basis of local comparative surgical audit for assessment and maintenance of quality care.
An efficiency-decay model for Lumen maintenance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bobashev, Georgiy; Baldasaro, Nicholas G.; Mills, Karmann C.
Proposed is a multicomponent model for the estimation of light-emitting diode (LED) lumen maintenance using test data that were acquired in accordance with the test standards of the Illumination Engineering Society of North America, i.e., LM-80-08. Lumen maintenance data acquired with this test do not always follow exponential decay, particularly data collected in the first 1000 h or under low-stress (e.g., low temperature) conditions. This deviation from true exponential behavior makes it difficult to use the full data set in models for the estimation of lumen maintenance decay coefficient. As a result, critical information that is relevant to the earlymore » life or low-stress operation of LED light sources may be missed. We present an efficiency-decay model approach, where all lumen maintenance data can be used to provide an alternative estimate of the decay rate constant. The approach considers a combined model wherein one part describes an initial “break-in” period and another part describes the decay in lumen maintenance. During the break-in period, several mechanisms within the LED can act to produce a small (typically <; 10%) increase in luminous flux. The effect of the break-in period and its longevity is more likely to be present at low-ambient temperatures and currents, where the discrepancy between a standard TM-21 approach and our proposed model is the largest. For high temperatures and currents, the difference between the estimates becomes nonsubstantial. Finally, our approach makes use of all the collected data and avoids producing unrealistic estimates of the decay coefficient.« less
An efficiency-decay model for Lumen maintenance
Bobashev, Georgiy; Baldasaro, Nicholas G.; Mills, Karmann C.; ...
2016-08-25
Proposed is a multicomponent model for the estimation of light-emitting diode (LED) lumen maintenance using test data that were acquired in accordance with the test standards of the Illumination Engineering Society of North America, i.e., LM-80-08. Lumen maintenance data acquired with this test do not always follow exponential decay, particularly data collected in the first 1000 h or under low-stress (e.g., low temperature) conditions. This deviation from true exponential behavior makes it difficult to use the full data set in models for the estimation of lumen maintenance decay coefficient. As a result, critical information that is relevant to the earlymore » life or low-stress operation of LED light sources may be missed. We present an efficiency-decay model approach, where all lumen maintenance data can be used to provide an alternative estimate of the decay rate constant. The approach considers a combined model wherein one part describes an initial “break-in” period and another part describes the decay in lumen maintenance. During the break-in period, several mechanisms within the LED can act to produce a small (typically <; 10%) increase in luminous flux. The effect of the break-in period and its longevity is more likely to be present at low-ambient temperatures and currents, where the discrepancy between a standard TM-21 approach and our proposed model is the largest. For high temperatures and currents, the difference between the estimates becomes nonsubstantial. Finally, our approach makes use of all the collected data and avoids producing unrealistic estimates of the decay coefficient.« less
Model of spacecraft atomic oxygen and solar exposure microenvironments
NASA Technical Reports Server (NTRS)
Bourassa, R. J.; Pippin, H. G.
1993-01-01
Computer models of environmental conditions in Earth orbit are needed for the following reasons: (1) derivation of material performance parameters from orbital test data, (2) evaluation of spacecraft hardware designs, (3) prediction of material service life, and (4) scheduling spacecraft maintenance. To meet these needs, Boeing has developed programs for modeling atomic oxygen (AO) and solar radiation exposures. The model allows determination of AO and solar ultraviolet (UV) radiation exposures for spacecraft surfaces (1) in arbitrary orientations with respect to the direction of spacecraft motion, (2) overall ranges of solar conditions, and (3) for any mission duration. The models have been successfully applied to prediction of experiment environments on the Long Duration Exposure Facility (LDEF) and for analysis of selected hardware designs for deployment on other spacecraft. The work on these models has been reported at previous LDEF conferences. Since publication of these reports, a revision has been made to the AO calculation for LDEF, and further work has been done on the microenvironments model for solar exposure.
Modeling of BN Lifetime Prediction of a System Based on Integrated Multi-Level Information
Wang, Xiaohong; Wang, Lizhi
2017-01-01
Predicting system lifetime is important to ensure safe and reliable operation of products, which requires integrated modeling based on multi-level, multi-sensor information. However, lifetime characteristics of equipment in a system are different and failure mechanisms are inter-coupled, which leads to complex logical correlations and the lack of a uniform lifetime measure. Based on a Bayesian network (BN), a lifetime prediction method for systems that combine multi-level sensor information is proposed. The method considers the correlation between accidental failures and degradation failure mechanisms, and achieves system modeling and lifetime prediction under complex logic correlations. This method is applied in the lifetime prediction of a multi-level solar-powered unmanned system, and the predicted results can provide guidance for the improvement of system reliability and for the maintenance and protection of the system. PMID:28926930
Modeling of BN Lifetime Prediction of a System Based on Integrated Multi-Level Information.
Wang, Jingbin; Wang, Xiaohong; Wang, Lizhi
2017-09-15
Predicting system lifetime is important to ensure safe and reliable operation of products, which requires integrated modeling based on multi-level, multi-sensor information. However, lifetime characteristics of equipment in a system are different and failure mechanisms are inter-coupled, which leads to complex logical correlations and the lack of a uniform lifetime measure. Based on a Bayesian network (BN), a lifetime prediction method for systems that combine multi-level sensor information is proposed. The method considers the correlation between accidental failures and degradation failure mechanisms, and achieves system modeling and lifetime prediction under complex logic correlations. This method is applied in the lifetime prediction of a multi-level solar-powered unmanned system, and the predicted results can provide guidance for the improvement of system reliability and for the maintenance and protection of the system.
Optimization as a Tool for Consistency Maintenance in Multi-Resolution Simulation
NASA Technical Reports Server (NTRS)
Drewry, Darren T; Reynolds, Jr , Paul F; Emanuel, William R
2006-01-01
The need for new approaches to the consistent simulation of related phenomena at multiple levels of resolution is great. While many fields of application would benefit from a complete and approachable solution to this problem, such solutions have proven extremely difficult. We present a multi-resolution simulation methodology that uses numerical optimization as a tool for maintaining external consistency between models of the same phenomena operating at different levels of temporal and/or spatial resolution. Our approach follows from previous work in the disparate fields of inverse modeling and spacetime constraint-based animation. As a case study, our methodology is applied to two environmental models of forest canopy processes that make overlapping predictions under unique sets of operating assumptions, and which execute at different temporal resolutions. Experimental results are presented and future directions are addressed.
Pragmatic Applications of RE-AIM for Health Care Initiatives in Community and Clinical Settings
Estabrooks, Paul E.
2018-01-01
The RE-AIM (Reach Effectiveness Adoption Implementation Maintenance) planning and evaluation framework has been applied broadly, but users often have difficulty in applying the model because of data collection needs across multiple domains and sources. Questions in the more common “who, what, where, how, when, and why” format may be an effective guide to ensure that individual participants, organization staff, and the perspectives of the setting are considered in planning and evaluation. Such a format can also help users in typical community and clinical settings to identify which outcomes are most valued and to focus limited measurement resources. Translations of RE-AIM that are easy to understand and apply are needed for application in real-world community and clinical settings where research and evaluation resources are limited. The purpose of this article is to provide simplified, pragmatic, user-centered and stakeholder-centered recommendations to increase the use of RE-AIM in community and clinical settings and in translational research. PMID:29300695
Chen, Innie; Money, Deborah; Yong, Paul; Williams, Christina; Allaire, Catherine
2015-09-01
Chronic pelvic pain (CPP) is a prevalent, debilitating, and costly condition. Although national guidelines and empiric evidence support the use of a multidisciplinary model of care for such patients, such clinics are uncommon in Canada. The BC Women's Centre for Pelvic Pain and Endometriosis was created to respond to this need, and there is interest in this model of care's impact on the burden of disease in British Columbia. We sought to create an approach to its evaluation using the RE-AIM (Reach, Efficacy, Adoption, Implementation, Maintenance) evaluation framework to assess the impact of the care model and to guide clinical decision-making and policy. The RE-AIM evaluation framework was applied to consider the different dimensions of impact of the BC Centre. The proposed measures, data sources, and data management strategies for this mixed-methods approach were identified. The five dimensions of impact were considered at individual and organizational levels, and corresponding indicators were proposed to enable integration into existing data infrastructure to facilitate collection and early program evaluation. The RE-AIM framework can be applied to the evaluation of a multidisciplinary chronic pelvic pain clinic. This will allow better assessment of the impact of innovative models of care for women with chronic pelvic pain.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-04
.... SUMMARY: EPA is approving a revision to the Beaumont/Port Arthur (BPA) 1997 8-hour ozone maintenance air... emissions model. The BPA 1997 8-hour ozone maintenance area consists of Hardin, Jefferson, and Orange... proposed to approve a revision to the BPA 1997 8-hour ozone maintenance air quality SIP by replacing the...
MDOT Pavement Management System : Prediction Models and Feedback System
DOT National Transportation Integrated Search
2000-10-01
As a primary component of a Pavement Management System (PMS), prediction models are crucial for one or more of the following analyses: : maintenance planning, budgeting, life-cycle analysis, multi-year optimization of maintenance works program, and a...
Reliability-centered maintenance for ground-based large optical telescopes and radio antenna arrays
NASA Astrophysics Data System (ADS)
Marchiori, G.; Formentin, F.; Rampini, F.
2014-07-01
In the last years, EIE GROUP has been more and more involved in large optical telescopes and radio antennas array projects. In this frame, the paper describes a fundamental aspect of the Logistic Support Analysis (LSA) process, that is the application of the Reliability-Centered Maintenance (RCM) methodology for the generation of maintenance plans for ground-based large optical telescopes and radio antennas arrays. This helps maintenance engineers to make sure that the telescopes continue to work properly, doing what their users require them to do in their present operating conditions. The main objective of the RCM process is to establish the complete maintenance regime, with the safe minimum required maintenance, carried out without any risk to personnel, telescope and subsystems. At the same time, a correct application of the RCM allows to increase the cost effectiveness, telescope uptime and items availability, and to provide greater understanding of the level of risk that the organization is managing. At the same time, engineers shall make a great effort since the initial phase of the project to obtain a telescope requiring easy maintenance activities and simple replacement of the major assemblies, taking special care on the accesses design and items location, implementation and design of special lifting equipment and handling devices for the heavy items. This maintenance engineering framework is based on seven points, which lead to the main steps of the RCM program. The initial steps of the RCM process consist of: system selection and data collection (MTBF, MTTR, etc.), definition of system boundaries and operating context, telescope description with the use of functional block diagrams, and the running of a FMECA to address the dominant causes of equipment failure and to lay down the Critical Items List. In the second part of the process the RCM logic is applied, which helps to determine the appropriate maintenance tasks for each identified failure mode. Once the logic is completed for all the analyzed items, the resulting Maintenance Program is compiled in order to preserve all the system important functions and to rationalize the tasks periodicities. Lastly, the RCM is kept alive throughout the entire life of the telescope, where the effectiveness of the maintenance is constantly reviewed and adjusted on the basis of the "lesson learned". In addition to the RCM analysis methodology, a second basic concept is applied for the telescope maintenance: to design and install components in such a manner to restore a failure and to perform servicing procedures as close as possible to the telescope, maximizing the replacement of Line Replaceable Units (LRUs) or Shop Replaceable Units (SRUs), rather than repair on-equipment.
NASA Technical Reports Server (NTRS)
Hops, J. M.; Sherif, J. S.
1994-01-01
A great deal of effort is now being devoted to the study, analysis, prediction, and minimization of software maintenance expected cost, long before software is delivered to users or customers. It has been estimated that, on the average, the effort spent on software maintenance is as costly as the effort spent on all other software costs. Software design methods should be the starting point to aid in alleviating the problems of software maintenance complexity and high costs. Two aspects of maintenance deserve attention: (1) protocols for locating and rectifying defects, and for ensuring that noe new defects are introduced in the development phase of the software process; and (2) protocols for modification, enhancement, and upgrading. This article focuses primarily on the second aspect, the development of protocols to help increase the quality and reduce the costs associated with modifications, enhancements, and upgrades of existing software. This study developed parsimonious models and a relative complexity metric for complexity measurement of software that were used to rank the modules in the system relative to one another. Some success was achieved in using the models and the relative metric to identify maintenance-prone modules.
The contributions of human factors on human error in Malaysia aviation maintenance industries
NASA Astrophysics Data System (ADS)
Padil, H.; Said, M. N.; Azizan, A.
2018-05-01
Aviation maintenance is a multitasking activity in which individuals perform varied tasks under constant pressure to meet deadlines as well as challenging work conditions. These situational characteristics combined with human factors can lead to various types of human related errors. The primary objective of this research is to develop a structural relationship model that incorporates human factors, organizational factors, and their impact on human errors in aviation maintenance. Towards that end, a questionnaire was developed which was administered to Malaysian aviation maintenance professionals. Structural Equation Modelling (SEM) approach was used in this study utilizing AMOS software. Results showed that there were a significant relationship of human factors on human errors and were tested in the model. Human factors had a partial effect on organizational factors while organizational factors had a direct and positive impact on human errors. It was also revealed that organizational factors contributed to human errors when coupled with human factors construct. This study has contributed to the advancement of knowledge on human factors effecting safety and has provided guidelines for improving human factors performance relating to aviation maintenance activities and could be used as a reference for improving safety performance in the Malaysian aviation maintenance companies.
36 CFR 1222.2 - What definitions apply to this part?
Code of Federal Regulations, 2012 CFR
2012-07-01
... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false What definitions apply to this part? 1222.2 Section 1222.2 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Identifying Federal Records § 1222...
36 CFR 1222.2 - What definitions apply to this part?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false What definitions apply to this part? 1222.2 Section 1222.2 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Identifying Federal Records § 1222...
36 CFR 1222.2 - What definitions apply to this part?
Code of Federal Regulations, 2014 CFR
2014-07-01
... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false What definitions apply to this part? 1222.2 Section 1222.2 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Identifying Federal Records § 1222...
36 CFR 1222.2 - What definitions apply to this part?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false What definitions apply to this part? 1222.2 Section 1222.2 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Identifying Federal Records § 1222...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tahvili, Sahar; Österberg, Jonas; Silvestrov, Sergei
One of the most important factors in the operations of many cooperations today is to maximize profit and one important tool to that effect is the optimization of maintenance activities. Maintenance activities is at the largest level divided into two major areas, corrective maintenance (CM) and preventive maintenance (PM). When optimizing maintenance activities, by a maintenance plan or policy, we seek to find the best activities to perform at each point in time, be it PM or CM. We explore the use of stochastic simulation, genetic algorithms and other tools for solving complex maintenance planning optimization problems in terms ofmore » a suggested framework model based on discrete event simulation.« less
20 CFR 416.1145 - How the presumed value rule applies in a nonmedical for-profit institution.
Code of Federal Regulations, 2011 CFR
2011-04-01
... payment in full to be the current market value of whatever food or shelter the institution provides. If... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false How the presumed value rule applies in a... Maintenance § 416.1145 How the presumed value rule applies in a nonmedical for-profit institution. If you live...
Code of Federal Regulations, 2011 CFR
2011-07-01
... obligation exists. (2) 8-Hour NAAQS Nonattainment/1-Hour NAAQS Maintenance. An area designated nonattainment for the 8-hour NAAQS that is a maintenance area for the 1-hour NAAQS at the time of designation for... deferred for so long as the area continues to maintain the 8-hour NAAQS; and (2) No longer applies once the...
Code of Federal Regulations, 2014 CFR
2014-07-01
... obligation exists. (2) 8-Hour NAAQS Nonattainment/1-Hour NAAQS Maintenance. An area designated nonattainment for the 8-hour NAAQS that is a maintenance area for the 1-hour NAAQS at the time of designation for... deferred for so long as the area continues to maintain the 8-hour NAAQS; and (2) No longer applies once the...
Code of Federal Regulations, 2010 CFR
2010-07-01
... obligation exists. (2) 8-Hour NAAQS Nonattainment/1-Hour NAAQS Maintenance. An area designated nonattainment for the 8-hour NAAQS that is a maintenance area for the 1-hour NAAQS at the time of designation for... deferred for so long as the area continues to maintain the 8-hour NAAQS; and (2) No longer applies once the...
Code of Federal Regulations, 2012 CFR
2012-07-01
... obligation exists. (2) 8-Hour NAAQS Nonattainment/1-Hour NAAQS Maintenance. An area designated nonattainment for the 8-hour NAAQS that is a maintenance area for the 1-hour NAAQS at the time of designation for... deferred for so long as the area continues to maintain the 8-hour NAAQS; and (2) No longer applies once the...
Code of Federal Regulations, 2013 CFR
2013-07-01
... obligation exists. (2) 8-Hour NAAQS Nonattainment/1-Hour NAAQS Maintenance. An area designated nonattainment for the 8-hour NAAQS that is a maintenance area for the 1-hour NAAQS at the time of designation for... deferred for so long as the area continues to maintain the 8-hour NAAQS; and (2) No longer applies once the...
Flight Crew Health Maintenance
NASA Technical Reports Server (NTRS)
Gullett, C. C.
1970-01-01
The health maintenance program for commercial flight crew personnel includes diet, weight control, and exercise to prevent heart disease development and disability grounding. The very high correlation between hypertension and overweight in cardiovascular diseases significantly influences the prognosis for a coronary prone individual and results in a high rejection rate of active military pilots applying for civilian jobs. In addition to physical fitness the major items stressed in pilot selection are: emotional maturity, glucose tolerance, and family health history.
Automated System Checkout to Support Predictive Maintenance for the Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Patterson-Hine, Ann; Deb, Somnath; Kulkarni, Deepak; Wang, Yao; Lau, Sonie (Technical Monitor)
1998-01-01
The Propulsion Checkout and Control System (PCCS) is a predictive maintenance software system. The real-time checkout procedures and diagnostics are designed to detect components that need maintenance based on their condition, rather than using more conventional approaches such as scheduled or reliability centered maintenance. Predictive maintenance can reduce turn-around time and cost and increase safety as compared to conventional maintenance approaches. Real-time sensor validation, limit checking, statistical anomaly detection, and failure prediction based on simulation models are employed. Multi-signal models, useful for testability analysis during system design, are used during the operational phase to detect and isolate degraded or failed components. The TEAMS-RT real-time diagnostic engine was developed to utilize the multi-signal models by Qualtech Systems, Inc. Capability of predicting the maintenance condition was successfully demonstrated with a variety of data, from simulation to actual operation on the Integrated Propulsion Technology Demonstrator (IPTD) at Marshall Space Flight Center (MSFC). Playback of IPTD valve actuations for feature recognition updates identified an otherwise undetectable Main Propulsion System 12 inch prevalve degradation. The algorithms were loaded into the Propulsion Checkout and Control System for further development and are the first known application of predictive Integrated Vehicle Health Management to an operational cryogenic testbed. The software performed successfully in real-time, meeting the required performance goal of 1 second cycle time.
Modelling Wind Turbine Failures based on Weather Conditions
NASA Astrophysics Data System (ADS)
Reder, Maik; Melero, Julio J.
2017-11-01
A large proportion of the overall costs of a wind farm is directly related to operation and maintenance (O&M) tasks. By applying predictive O&M strategies rather than corrective approaches these costs can be decreased significantly. Here, especially wind turbine (WT) failure models can help to understand the components’ degradation processes and enable the operators to anticipate upcoming failures. Usually, these models are based on the age of the systems or components. However, latest research shows that the on-site weather conditions also affect the turbine failure behaviour significantly. This study presents a novel approach to model WT failures based on the environmental conditions to which they are exposed to. The results focus on general WT failures, as well as on four main components: gearbox, generator, pitch and yaw system. A penalised likelihood estimation is used in order to avoid problems due to for example highly correlated input covariates. The relative importance of the model covariates is assessed in order to analyse the effect of each weather parameter on the model output.
Bona, Silvia; Silvanto, Juha
2014-01-01
Currently influential models of working memory posit that memory content is highly accessible to conscious inspection. These models predict that metacognition of memory performance should go hand-in-hand with the accuracy of the underlying memory representation. To test this view, we investigated how visual information presented during the maintenance period affects VSTM accuracy and confidence. We used a delayed cue-target orientation discrimination task in which participants were asked to hold in memory a grating, and during the maintenance period a second memory cue could be presented. VSTM accuracy of the first memory cue was impaired when the orientation of the second memory cue was sufficiently different. However, participants' response confidence was reduced whenever the second memory cue was presented; thus VSTM accuracy and confidence were dissociated. In a second experiment, we applied transcranial direct current stimulation (tDCS) over the right dorsolateral prefrontal cortex (DLPFC) to investigate the causal role of this region in VSTM metacognition. Relative to the sham condition, anodal tDCS induced a general reduction in confidence ratings but did not affect VSTM accuracy. Overall, these results indicate that our metacognition of memory performance is influenced by factors other than the accuracy of the underlying memory representation.
Bona, Silvia; Silvanto, Juha
2014-01-01
Currently influential models of working memory posit that memory content is highly accessible to conscious inspection. These models predict that metacognition of memory performance should go hand-in-hand with the accuracy of the underlying memory representation. To test this view, we investigated how visual information presented during the maintenance period affects VSTM accuracy and confidence. We used a delayed cue–target orientation discrimination task in which participants were asked to hold in memory a grating, and during the maintenance period a second memory cue could be presented. VSTM accuracy of the first memory cue was impaired when the orientation of the second memory cue was sufficiently different. However, participants' response confidence was reduced whenever the second memory cue was presented; thus VSTM accuracy and confidence were dissociated. In a second experiment, we applied transcranial direct current stimulation (tDCS) over the right dorsolateral prefrontal cortex (DLPFC) to investigate the causal role of this region in VSTM metacognition. Relative to the sham condition, anodal tDCS induced a general reduction in confidence ratings but did not affect VSTM accuracy. Overall, these results indicate that our metacognition of memory performance is influenced by factors other than the accuracy of the underlying memory representation. PMID:24663094
NASA Astrophysics Data System (ADS)
Polverino, Pierpaolo; Esposito, Angelo; Pianese, Cesare; Ludwig, Bastian; Iwanschitz, Boris; Mai, Andreas
2016-02-01
In the current energetic scenario, Solid Oxide Fuel Cells (SOFCs) exhibit appealing features which make them suitable for environmental-friendly power production, especially for stationary applications. An example is represented by micro-combined heat and power (μ-CHP) generation units based on SOFC stacks, which are able to produce electric and thermal power with high efficiency and low pollutant and greenhouse gases emissions. However, the main limitations to their diffusion into the mass market consist in high maintenance and production costs and short lifetime. To improve these aspects, the current research activity focuses on the development of robust and generalizable diagnostic techniques, aimed at detecting and isolating faults within the entire system (i.e. SOFC stack and balance of plant). Coupled with appropriate recovery strategies, diagnosis can prevent undesired system shutdowns during faulty conditions, with consequent lifetime increase and maintenance costs reduction. This paper deals with the on-line experimental validation of a model-based diagnostic algorithm applied to a pre-commercial SOFC system. The proposed algorithm exploits a Fault Signature Matrix based on a Fault Tree Analysis and improved through fault simulations. The algorithm is characterized on the considered system and it is validated by means of experimental induction of faulty states in controlled conditions.
14 CFR 91.1109 - Aircraft maintenance: Inspection program.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aircraft maintenance: Inspection program... Ownership Operations Program Management § 91.1109 Aircraft maintenance: Inspection program. Each program... conduct of inspections for the particular make and model aircraft, including necessary tests and checks...
14 CFR 91.1109 - Aircraft maintenance: Inspection program.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft maintenance: Inspection program... Ownership Operations Program Management § 91.1109 Aircraft maintenance: Inspection program. Each program... conduct of inspections for the particular make and model aircraft, including necessary tests and checks...
14 CFR 91.1109 - Aircraft maintenance: Inspection program.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aircraft maintenance: Inspection program... Ownership Operations Program Management § 91.1109 Aircraft maintenance: Inspection program. Each program... conduct of inspections for the particular make and model aircraft, including necessary tests and checks...
ERIC Educational Resources Information Center
Cannon, Glenn; Jobe, Holly
Proper cleaning and storage of audiovisual aids is outlined in this brief guide. Materials and equipment needed for first line maintenance are listed, as well as maintenance procedures for records, audio and video tape, film, filmstrips, slides, realia, models, prints, graphics, maps, and overhead transparencies. A 15-item quiz on software…
On the application of copula in modeling maintenance contract
NASA Astrophysics Data System (ADS)
Iskandar, B. P.; Husniah, H.
2016-02-01
This paper deals with the application of copula in maintenance contracts for a nonrepayable item. Failures of the item are modeled using a two dimensional approach where age and usage of the item and this requires a bi-variate distribution to modelling failures. When the item fails then corrective maintenance (CM) is minimally repaired. CM can be outsourced to an external agent or done in house. The decision problem for the owner is to find the maximum total profit whilst for the agent is to determine the optimal price of the contract. We obtain the mathematical models of the decision problems for the owner as well as the agent using a Nash game theory formulation.
Optimisation of maintenance concept choice using risk-decision factor - a case study
NASA Astrophysics Data System (ADS)
Popovic, Vladimir M.; Vasic, Branko M.; Rakicevic, Branislav B.; Vorotovic, Goran S.
2012-10-01
The design of maintenance system and the corresponding logistic support is a very complex process, during which the aim is to find the compromise solutions regarding the relations among different maintenance procedures and the ways of their implementation. As a result of this, various solutions can be adopted, since this is conditioned by a series of important factors and criteria, which can be contradictory sometimes. There are different perspectives on ways of solving practical maintenance problems, that is dilemmas when it comes to the choice of maintenance concept. The principal dilemma is how and when to decide on carrying out maintenance procedures. Should the decision be based on theoretical grounds or experience, how does one reconcile those two extremes, who is to decide upon this? In this article we have offered one, basically new solution as a possibility for maintenance concept choice, based on a significant modification of the widely used failure modes and effects analysis (FMEA) method. This solution is risk-decision factor (RDF). This is a result of seven parameters (of different importance and weight) that have the key impact on the process of production and logistic support. The application of this factor is illustrated by the example of planning, organisation and functioning of the maintenance system applied in The Institute for Manufacturing Banknotes and Coins (ZIN) in Belgrade.
A novel vacuum assisted closure therapy model for use with percutaneous devices.
Cook, Saranne J; Nichols, Francesca R; Brunker, Lucille B; Bachus, Kent N
2014-06-01
Long-term maintenance of a dermal barrier around a percutaneous prosthetic device remains a common clinical problem. A technique known as Negative Pressure Wound Therapy (NPWT) uses negative pressure to facilitate healing of impaired and complex soft tissue wounds. However, the combination of using negative pressure with percutaneous prosthetic devices has not been investigated. The goal of this study was to develop a methodology to apply negative pressure to the tissues surrounding a percutaneous device in an animal model; no tissue healing outcomes are presented. Specifically, four hairless rats received percutaneous porous coated titanium devices implanted on the dorsum and were bandaged with a semi occlusive film dressing. Two of these animals received NPWT; two animals received no NPWT and served as baseline controls. Over a 28-day period, both the number of dressing changes required between the two groups as well as the pressures were monitored. Negative pressures were successfully applied to the periprosthetic tissues in a clinically relevant range with a manageable number of dressing changes. This study provides a method for establishing, maintaining, and quantifying controlled negative pressures to the tissues surrounding percutaneous devices using a small animal model. Published by Elsevier Ltd.
33 CFR 241.4 - General policy.
Code of Federal Regulations, 2012 CFR
2012-07-01
... will be applied to construction costs only. Operations, maintenance and rehabilitation responsibilities... permitted to defer a certain percentage of the non-Federal share whenever current economic circumstances...
33 CFR 241.4 - General policy.
Code of Federal Regulations, 2014 CFR
2014-07-01
... will be applied to construction costs only. Operations, maintenance and rehabilitation responsibilities... permitted to defer a certain percentage of the non-Federal share whenever current economic circumstances...
33 CFR 241.4 - General policy.
Code of Federal Regulations, 2013 CFR
2013-07-01
... will be applied to construction costs only. Operations, maintenance and rehabilitation responsibilities... permitted to defer a certain percentage of the non-Federal share whenever current economic circumstances...
Rojas, I F; Zepeda, M S; Zúñiga, H P
1990-11-01
The effectiveness of maintenance care program applied at different period of time was evaluate in patients treated for gingivitis and incipiente marginal periodontitis. Fifty six patients were divided in three groups, each one controlled three times (each 2, 4 and 6 months respectively), to evaluate periodontal health. At each control, gingival index and plaque index was registered and patients had profilaxis and reinforcement of dental care instructions. All patients knew and practiced a control plaque control during active treatment. Results demonstrated that maintenance care program applied each 2 months, could get better clinical healthy periodontal conditions, without influence of patient's control plaque. Those patients with good hygiene could provide for an acceptable level of periodontal health even in patients controlled each 4 and 6 months. Positive correlations between controls in each index are indicative for that. Age seemingly do not have influence like etiological factor of recurrence inflammation. High correlation between plaque index and gingival index was found in every control mainly in the groups controlled each 4 and 6 months.
A Context Maintenance and Retrieval Model of Organizational Processes in Free Recall
ERIC Educational Resources Information Center
Polyn, Sean M.; Norman, Kenneth A.; Kahana, Michael J.
2009-01-01
The authors present the context maintenance and retrieval (CMR) model of memory search, a generalized version of the temporal context model of M. W. Howard and M. J. Kahana (2002a), which proposes that memory search is driven by an internally maintained context representation composed of stimulus-related and source-related features. In the CMR…
NASA Technical Reports Server (NTRS)
Lemanski, A. J.
1976-01-01
Helicopter drive-system technology which would result in the largest benefit in direct maintenance cost when applied to civil helicopters in the 1980 timeframe was developed. A prototype baseline drive system based on 1975 technology provided the basis for comparison against the proposed advanced technology in order to determine the potential for each area recommended for improvement. A specific design example of an advanced-technology main transmission is presented to define improvements for maintainability, weight, producibility, reliability, noise, vibration, and diagnostics. Projections of the technology achievable in the 1980 timeframe are presented. Based on this data, the technologies with the highest payoff (lowest direct maintenance cost) for civil-helicopter drive systems are identified.
36 CFR 1222.10 - How should agencies apply the statutory definition of Federal records?
Code of Federal Regulations, 2012 CFR
2012-07-01
... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false How should agencies apply the statutory definition of Federal records? 1222.10 Section 1222.10 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS...
36 CFR 1222.10 - How should agencies apply the statutory definition of Federal records?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false How should agencies apply the statutory definition of Federal records? 1222.10 Section 1222.10 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS...
36 CFR 1222.10 - How should agencies apply the statutory definition of Federal records?
Code of Federal Regulations, 2014 CFR
2014-07-01
... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false How should agencies apply the statutory definition of Federal records? 1222.10 Section 1222.10 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS...
40 CFR 52.2780 - Control strategy for sulfur oxides.
Code of Federal Regulations, 2010 CFR
2010-07-01
... maintenance of the national ambient air quality standards for sulfur oxides on the island of St. Croix. (b...) The entire regulation as it applies to the islands of St. Thomas and St. John. (2) The entire... island of St. Croix. (3) The entire regulation excluding subsection (a)(2) as it applies to the remaining...
Genetic variation in telomere maintenance genes, telomere length and breast cancer risk.
Shen, Jing; Terry, Mary Beth; Liao, Yuyan; Gurvich, Irina; Wang, Qiao; Senie, Ruby T; Santella, Regina M
2012-01-01
Telomeres at the ends of eukaryotic chromosomes play a critical role in maintaining the integrity and stability of the genome and participate in the initiation of DNA damage/repair responses. We performed a case-control study to evaluate the role of three SNPs (TERT-07, TERT-54 and POT1-03) in telomere maintenance genes previously found to be significantly associated with breast cancer risk. We used sister-sets obtained from the New York site of the Breast Cancer Family Registry (BCFR). Among the 313 sister-sets, there were 333 breast cancer cases and 409 unaffected sisters who were evaluated in the current study. We separately applied conditional logistic regression and generalized estimating equations (GEE) models to evaluate associations between the three SNPs and breast cancer risk within sister-sets. We examined the associations between genotype, covariates and telomere length among unaffected sisters using a GEE model. We found no significant associations between the three SNPs in telomere maintenance genes and breast cancer risk by both conditional logistic regression and GEE models, nor were these SNPs significantly related to telomere length. Among unaffected sisters, shortened telomeres were statistically significantly correlated with never hormone replacement therapy (HRT) use. Increased duration of HRT use was significantly associated with reduced telomere length. The means of telomere length were 0.77 (SD = 0.35) for never HRT use, 0.67 (SD = 0.29) for HRT use < 5 yrs and 0.59 (SD = 0.24) for HRT use ≥ 5 yrs after adjusting for age of blood donation and race and ethnicity. We found that exogenous hormonal exposure was inversely associated with telomere length. No significant associations between genetic variants and telomere length or breast cancer risk were observed. These findings provide initial evidence to understand hormonal exposure in the regulation of telomere length and breast cancer risk but need replication in prospective studies.
Influence of the Mesh Geometry Evolution on Gearbox Dynamics during Its Maintenance
NASA Astrophysics Data System (ADS)
Dąbrowski, Z.; Dziurdź, J.; Klekot, G.
2017-12-01
Toothed gears constitute the necessary elements of power transmission systems. They are applied as stationary devices in drive systems of road vehicles, ships and crafts as well as airplanes and helicopters. One of the problems related to the toothed gears usage is the determination of their technical state or its evolutions. Assuming that the gear slippage velocity is attributed to vibrations and noises generated by cooperating toothed wheels, the application of a simple cooperation model of rolled wheels of skew teeth is proposed for the analysis of the mesh evolution influence on the gear dynamics. In addition, an example of utilising an ordinary coherence function for investigating evolutionary mesh changes related to the effects impossible to be described by means of the simple kinematic model is presented.
Towards the Enhancement of "MINOR" Archaeological Heritage
NASA Astrophysics Data System (ADS)
Morandi, S.; Tremari, M.; Mandelli, A.
2017-02-01
The research is an analysis of the recording, reconstruction and visualisation of the 3D data of a XVIII century watermill, identified in an emergency archaeological excavation during the construction of the mini-hydroelectric plant on the bank of the Adda river in the municipality of Pizzighettone (Cremona, Lombardy, Italy). The work examines the use and the potentials of modern digital 3D modelling techniques applied to archaeological heritage aimed to increase the research, maintenance and presentation with interactive products. The use of three-dimensional models managed through AR (Augmented Reality) and VR (Virtual Reality) technologies with mobile devices gives several opportunities in the field of study and communication. It also improves on-site exploration of the landscape, enhancing the "minor" archaeological sites, daily subjected to numerous emergency works and facilitating the understanding of heritage sites.
Chen, Huan-Sheng; Cheng, Chun-Ting; Hou, Chun-Cheng; Liou, Hung-Hsiang; Chang, Cheng-Tsung; Lin, Chun-Ju; Wu, Tsai-Kun; Chen, Chang-Hsu; Lim, Paik-Seong
2017-07-01
Rapid screening and monitoring of nutritional status is mandatory in hemodialysis population because of the increasingly encountered nutritional problems. Considering the limitations of previous composite nutrition scores applied in this population, we tried to develop a standardized composite nutrition score (SCNS) using low lean tissue index as a marker of protein wasting to facilitate clinical screening and monitoring and to predict outcome. This retrospective cohort used 2 databases of dialysis populations from Taiwan between 2011 and 2014. First database consisting of data from 629 maintenance hemodialysis patients was used to develop the SCNS and the second database containing data from 297 maintenance hemodialysis patients was used to validate this developed score. SCNS containing albumin, creatinine, potassium, and body mass index was developed from the first database using low lean tissue index as a marker of protein wasting. When applying this score in the original database, significantly higher risk of developing protein wasting was found for patients with lower SCNS (odds ratio 1.38 [middle tertile vs highest tertile, P < .0001] and 2.40 [lowest tertile vs middle tertile, P < .0001]). The risk of death was also shown to be higher for patients with lower SCNS (hazard ratio 4.45 [below median level vs above median level, P < .0001]). These results were validated in the second database. We developed an SCNS consisting of 4 easily available biochemical parameters. This kind of scoring system can be easily applied in different dialysis facilities for screening and monitoring of protein wasting. The wide application of body composition monitor in dialysis population will also facilitate the development of specific nutrition scoring model for individual facility. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
1983-03-01
BUREAU OF STANDARDS-1963-A ,,...:-. .-. -.’" :.- --. . 4 Iq " USAAVRADCOM-TR-82-D-37 COMBAT MAINTENANCE CONCEPTS AND REPAIR TECHNIQUES USING SHAPE MEMORY...O APPLIED TECHNOLOGY LABORATORY POSITION STATEMENT The results of this effort determined the feasibility of using the full-ring shape memory alloy...specifications, or other data are used for any purpose other than in connection with a definitely related Government procurement operation, the United
ERIC Educational Resources Information Center
Hawaii State Office of the Auditor, Honolulu.
An act of the Hawaii legislature directed the State Auditor to study three areas of Hawaii's publication education: inventory add-on programs or programs that compete with the core curriculum for instructional time, review Chapter 37, HRS, on budgeting; and review Chapter 26, HRS, as it applies to repair and maintenance (R&M) of school…
76 FR 19716 - Airworthiness Directives; BAE SYSTEMS (Operations) Limited Model 4101 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-08
... Jetstream J41 Aircraft Maintenance Manual (AMM), includes the following chapters: --05-10-10 ``Airworthiness... Jetstream Series 4100 Aircraft Maintenance Manual, Revision 33, dated February 15, 2010. The actions...: * * * BAE Systems (Operations) Ltd has issued Revision 33 of the AMM [airplane maintenance manual] to amend...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-07
... aircraft for which a manufacturer's maintenance manual or instructions for continued airworthiness has been... maintenance program by incorporating new airworthiness limitations (AWLs) for fuel tank systems to satisfy... latent failures, alterations, repairs, or maintenance actions, which, in combination with flammable fuel...
Airline Maintenance Manpower Optimization from the De Novo Perspective
NASA Astrophysics Data System (ADS)
Liou, James J. H.; Tzeng, Gwo-Hshiung
Human resource management (HRM) is an important issue for today’s competitive airline marketing. In this paper, we discuss a multi-objective model designed from the De Novo perspective to help airlines optimize their maintenance manpower portfolio. The effectiveness of the model and solution algorithm is demonstrated in an empirical study of the optimization of the human resources needed for airline line maintenance. Both De Novo and traditional multiple objective programming (MOP) methods are analyzed. A comparison of the results with those of traditional MOP indicates that the proposed model and solution algorithm does provide better performance and an improved human resource portfolio.
Modeling strength data for CREW CHIEF
NASA Technical Reports Server (NTRS)
Mcdaniel, Joe W.
1990-01-01
The Air Force has developed CREW CHIEF, a computer-aided design (CAD) tool for simulating and evaluating aircraft maintenance to determine if the required activities are feasible. CREW CHIEF gives the designer the ability to simulate maintenance activities with respect to reach, accessibility, strength, hand tool operation, and materials handling. While developing the CREW CHIEF, extensive research was performed to describe workers strength capabilities for using hand tools and manual handling of objects. More than 100,000 strength measures were collected and modeled for CREW CHIEF. These measures involved both male and female subjects in the 12 maintenance postures included in CREW CHIEF. The data collection and modeling effort are described.
Case management of persons with acquired immunodeficiency syndrome in San Francisco
Benjamin, A. E.; Lee, Philip R.; Solkowitz, Sharon N.
1988-01-01
The acquired immunodeficiency syndrome (AIDS) epidemic represents a growing challenge for the health care system and for case management models applied to persons with AIDS. The experience of San Francisco highlights some of the issues involved in developing a case management system appropriate to the needs of persons with AIDS, as well as providers, and payers. Dramatic growth in the size and complexity of the AIDS caseload and the involvement of public, health maintenance organization, and community providers has required the increasing formalization and centralization of case management roles. Persistent questions about the definition and goals of case management complicate development of these services. PMID:10312974
Quantification of Gear Tooth Damage by Optimal Tracking of Vibration Signatures
NASA Technical Reports Server (NTRS)
Choy, F. K.; Veillette, R. J.; Polyshchuk, V.; Braun, M. J.; Hendricks, R. C.
1996-01-01
This paper presents a technique for quantifying the wear or damage of gear teeth in a transmission system. The procedure developed in this study can be applied as a part of either an onboard machine health-monitoring system or a health diagnostic system used during regular maintenance. As the developed methodology is based on analysis of gearbox vibration under normal operating conditions, no shutdown or special modification of operating parameters is required during the diagnostic process. The process of quantifying the wear or damage of gear teeth requires a set of measured vibration data and a model of the gear mesh dynamics. An optimization problem is formulated to determine the profile of a time-varying mesh stiffness parameter for which the model output approximates the measured data. The resulting stiffness profile is then related to the level of gear tooth wear or damage. The procedure was applied to a data set generated artificially and to another obtained experimentally from a spiral bevel gear test rig. The results demonstrate the utility of the procedure as part of an overall health-monitoring system.
BIM authoring for an image-based bridge maintenance system of existing cable-supported bridges
NASA Astrophysics Data System (ADS)
Dang, N. S.; Shim, C. S.
2018-04-01
Infrastructure nowadays is increasingly become the main backbone for the metropolitan development in general. Along with the rise of new facilities, the demand in term of maintenance for the existing bridges is indispensable. Recently, the terminology of “preventive maintenance” is not unfamiliar with the engineer, literally is the use of a bridge maintenance system (BMS) based on a BIM-oriented model. In this paper, the process of generating a BMS based on BIM model is introduced in detail. Data management for this BMS is separated into two modules: site inspection system and information management system. The noteworthy aspect of this model lays on the closed and automatic process of “capture image, generate the technical damage report, and upload/feedback to the BMS” in real-time. A pilot BMS system for a cable-supported bridge is presented which showed a good performance and potential to further development of preventive maintenance.
Policy for equipment’s leasing period extension with minimum cost of maintenance
NASA Astrophysics Data System (ADS)
Lestari, C.; Kurniati, N.
2018-04-01
The cost structure for equipment investment including purchase cost and maintenance cost is getting more expensive. The company considers to lease the equipment instead of purchase it under a contractual agreement. Offering to extend the lease period, following to the base lease period, will provide more benefits for both the lessor (owner) and the lessee (user). Whenever the lease period extension offered at the beginning of the contract, there are some risks in finance e.g. uncertainty of the equipment performance and lessor responsibility. Therefore, this research attempts to model the optimal maintenance policy for lease period extension offered at the end of the contract. Minimal repair is performed to rectify a failed equipment, while imperfect preventive maintenance is conducted to improve the operational state of the equipment when reaches a certain control limit to avoid failures. The mathematical model is constructed to determine the optimal control limit, the number and degree of preventive maintenance, and the multiplication number of the lease period extension. Finally, numerical examples are given to illustrate the influences of the optimal length of the extended lease and the maintenance policy to minimize the maintenance cost.
Automotive Maintenance Data Base for Model Years 1976-1979. Part I
DOT National Transportation Integrated Search
1980-12-01
An update of the existing data base was developed to include life cycle maintenance costs of representative vehicles for the model years 1976-1979. Repair costs as a function of time are also developed for a passenger car in each of the compact, subc...
Personalised Medicine: Genome Maintenance Lessons Learned from Studies in Yeast as a Model Organism.
Abugable, Arwa A; Awwad, Dahlia A; Fleifel, Dalia; Ali, Mohamed M; El-Khamisy, Sherif; Elserafy, Menattallah
2017-01-01
Yeast research has been tremendously contributing to the understanding of a variety of molecular pathways due to the ease of its genetic manipulation, fast doubling time as well as being cost-effective. The understanding of these pathways did not only help scientists learn more about the cellular functions but also assisted in deciphering the genetic and cellular defects behind multiple diseases. Hence, yeast research not only opened the doors for transforming basic research into applied research, but also paved the roads for improving diagnosis and innovating personalized therapy of different diseases. In this chapter, we discuss how yeast research has contributed to understanding major genome maintenance pathways such as the S-phase checkpoint activation pathways, repair via homologous recombination and non-homologous end joining as well as topoisomerases-induced protein linked DNA breaks repair. Defects in these pathways lead to neurodegenerative diseases and cancer. Thus, the understanding of the exact genetic defects underlying these diseases allowed the development of personalized medicine, improving the diagnosis and treatment and overcoming the detriments of current conventional therapies such as the side effects, toxicity as well as drug resistance.
Distinct brain networks for adaptive and stable task control in humans
Dosenbach, Nico U. F.; Fair, Damien A.; Miezin, Francis M.; Cohen, Alexander L.; Wenger, Kristin K.; Dosenbach, Ronny A. T.; Fox, Michael D.; Snyder, Abraham Z.; Vincent, Justin L.; Raichle, Marcus E.; Schlaggar, Bradley L.; Petersen, Steven E.
2007-01-01
Control regions in the brain are thought to provide signals that configure the brain's moment-to-moment information processing. Previously, we identified regions that carried signals related to task-control initiation, maintenance, and adjustment. Here we characterize the interactions of these regions by applying graph theory to resting state functional connectivity MRI data. In contrast to previous, more unitary models of control, this approach suggests the presence of two distinct task-control networks. A frontoparietal network included the dorsolateral prefrontal cortex and intraparietal sulcus. This network emphasized start-cue and error-related activity and may initiate and adapt control on a trial-by-trial basis. The second network included dorsal anterior cingulate/medial superior frontal cortex, anterior insula/frontal operculum, and anterior prefrontal cortex. Among other signals, these regions showed activity sustained across the entire task epoch, suggesting that this network may control goal-directed behavior through the stable maintenance of task sets. These two independent networks appear to operate on different time scales and affect downstream processing via dissociable mechanisms. PMID:17576922
Murray, Stuart B; Rieger, Elizabeth; Karlov, Lisa; Touyz, Stephen W
2013-03-01
Muscle dysmorphia is a psychiatric disorder that has been conceptually linked to eating disorders, although its precise nosology remains unclear. To further investigate this notion, the present study examined the applicability of the transdiagnostic model of eating disorders to muscle dysmorphia. One hundred and nineteen male undergraduate students completed self-report measures of multidimensional perfectionism, mood intolerance, self-esteem, interpersonal problems, and muscle dysmorphia symptomatology. Self-oriented perfectionism, socially prescribed perfectionism, mood intolerance, and low self-esteem significantly predicted muscle dysmorphia symptomatology, whereas other-oriented perfectionism and interpersonal problems did not demonstrate significant predictive value when accounting for the other transdiagnostic constructs. The transdiagnostic model of eating disorders may potentially be applied to enhance our understanding of the maintenance of muscle dysmorphic features in addition to eating disorder symptomatology. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Performance measurement integrated information framework in e-Manufacturing
NASA Astrophysics Data System (ADS)
Teran, Hilaida; Hernandez, Juan Carlos; Vizán, Antonio; Ríos, José
2014-11-01
The implementation of Internet technologies has led to e-Manufacturing technologies becoming more widely used and to the development of tools for compiling, transforming and synchronising manufacturing data through the Web. In this context, a potential area for development is the extension of virtual manufacturing to performance measurement (PM) processes, a critical area for decision making and implementing improvement actions in manufacturing. This paper proposes a PM information framework to integrate decision support systems in e-Manufacturing. Specifically, the proposed framework offers a homogeneous PM information exchange model that can be applied through decision support in e-Manufacturing environment. Its application improves the necessary interoperability in decision-making data processing tasks. It comprises three sub-systems: a data model, a PM information platform and PM-Web services architecture. A practical example of data exchange for measurement processes in the area of equipment maintenance is shown to demonstrate the utility of the model.
Wiemer, Julian; Pauli, Paul
2016-12-01
Fear-relevant illusory correlations (ICs) are defined as the overestimation of the relationship between a fear-relevant stimulus and aversive consequences. ICs reflect biased cognitions affecting the learning and unlearning of fear in anxiety disorders, and a deeper understanding might help to improve treatment. A model for the maintenance of ICs is proposed that highlights the importance of amplified aversiveness and salience of fear-relevant outcomes, impaired executive contingency monitoring and an availability heuristic. The model explains why ICs are enhanced in high fearful individuals and allows for some implications that might be applied to augment the effectiveness of cognitive behavior therapy, such as emotion regulation and the direction of attention to non-aversive experiences. Finally, we suggest possible future research directions and an alternative measure of ICs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Principles for the dynamic maintenance of cortical polarity
Marco, Eugenio; Wedlich-Soldner, Roland; Li, Rong; Altschuler, Steven J.; Wu, Lani F.
2007-01-01
Summary Diverse cell types require the ability to dynamically maintain polarized membrane protein distributions through balancing transport and diffusion. However, design principles underlying dynamically maintained cortical polarity are not well understood. Here we constructed a mathematical model for characterizing the morphology of dynamically polarized protein distributions. We developed analytical approaches for measuring all model parameters from single-cell experiments. We applied our methods to a well-characterized system for studying polarized membrane proteins: budding yeast cells expressing activated Cdc42. We found that balanced diffusion and colocalized transport to and from the plasma membrane were sufficient for accurately describing polarization morphologies. Surprisingly, the model predicts that polarized regions are defined with a precision that is nearly optimal for measured transport rates, and that polarity can be dynamically stabilized through positive feedback with directed transport. Our approach provides a step towards understanding how biological systems shape spatially precise, unambiguous cortical polarity domains using dynamic processes. PMID:17448998
Reliability and Maintainability model (RAM) user and maintenance manual. Part 2
NASA Technical Reports Server (NTRS)
Ebeling, Charles E.
1995-01-01
This report documents the procedures for utilizing and maintaining the Reliability and Maintainability Model (RAM) developed by the University of Dayton for the NASA Langley Research Center (LaRC). The RAM model predicts reliability and maintainability (R&M) parameters for conceptual space vehicles using parametric relationships between vehicle design and performance characteristics and subsystem mean time between maintenance actions (MTBM) and manhours per maintenance action (MH/MA). These parametric relationships were developed using aircraft R&M data from over thirty different military aircraft of all types. This report describes the general methodology used within the model, the execution and computational sequence, the input screens and data, the output displays and reports, and study analyses and procedures. A source listing is provided.
Ward, Marie; McDonald, Nick; Morrison, Rabea; Gaynor, Des; Nugent, Tony
2010-02-01
Aircraft maintenance is a highly regulated, safety critical, complex and competitive industry. There is a need to develop innovative solutions to address process efficiency without compromising safety and quality. This paper presents the case that in order to improve a highly complex system such as aircraft maintenance, it is necessary to develop a comprehensive and ecologically valid model of the operational system, which represents not just what is meant to happen, but what normally happens. This model then provides the backdrop against which to change or improve the system. A performance report, the Blocker Report, specific to aircraft maintenance and related to the model was developed gathering data on anything that 'blocks' task or check performance. A Blocker Resolution Process was designed to resolve blockers and improve the current check system. Significant results were obtained for the company in the first trial and implications for safety management systems and hazard identification are discussed. Statement of Relevance: Aircraft maintenance is a safety critical, complex, competitive industry with a need to develop innovative solutions to address process and safety efficiency. This research addresses this through the development of a comprehensive and ecologically valid model of the system linked with a performance reporting and resolution system.
Lineage Selection and the Maintenance of Sex.
de Vienne, Damien M; Giraud, Tatiana; Gouyon, Pierre-Henri
2013-01-01
Sex predominates in eukaryotes, despite its short-term disadvantage when compared to asexuality. Myriad models have suggested that short-term advantages of sex may be sufficient to counterbalance its twofold costs. However, despite decades of experimental work seeking such evidence, no evolutionary mechanism has yet achieved broad recognition as explanation for the maintenance of sex. We explore here, through lineage-selection models, the conditions favouring the maintenance of sex. In the first model, we allowed the rate of transition to asexuality to evolve, to determine whether lineage selection favoured species with the strongest constraints preventing the loss of sex. In the second model, we simulated more explicitly the mechanisms underlying the higher extinction rates of asexual lineages than of their sexual counterparts. We linked extinction rates to the ecological and/or genetic features of lineages, thereby providing a formalisation of the only figure included in Darwin's "The origin of species". Our results reinforce the view that the long-term advantages of sex and lineage selection may provide the most satisfactory explanations for the maintenance of sex in eukaryotes, which is still poorly recognized, and provide figures and a simulation website for training and educational purposes. Short-term benefits may play a role, but it is also essential to take into account the selection of lineages for a thorough understanding of the maintenance of sex.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-22
... emissions inventories, monitoring, and modeling, to assure attainment and maintenance of the standards... NAAQS required the deployment of a system of new monitors to measure ambient levels of that new... requirements, including emissions inventories, monitoring, and modeling to assure attainment and maintenance of...
Two Maintenance Mechanisms of Verbal Information in Working Memory
ERIC Educational Resources Information Center
Camos, V.; Lagner, P.; Barrouillet, P.
2009-01-01
The present study evaluated the interplay between two mechanisms of maintenance of verbal information in working memory, namely articulatory rehearsal as described in Baddeley's model, and attentional refreshing as postulated in Barrouillet and Camos's Time-Based Resource-Sharing (TBRS) model. In four experiments using complex span paradigm, we…
Automotive Maintenance Data Base for Model Years 1976-1979. Part II : Appendix E and F
DOT National Transportation Integrated Search
1980-12-01
An update of the existing data base was developed to include life cycle maintenance costs of representative vehicles for the model years 1976-1979. Repair costs as a function of time are also developed for a passenger car in each of the compact, subc...
Yan, Xiaojuan; Yang, Feng; Zhou, Hanyun; Zhang, Hongshen; Liu, Jianfei; Ma, Kezhong; Li, Yi; Zhu, Jun; Ding, Jianqiang
2015-01-01
Background VKORC1 is reported to be capable of treating several diseases with thrombotic risk, such as cardiac valve replacement. Some single-nucleotide polymorphisms (SNPs) in VKORC1 are documented to be associated with clinical differences in warfarin maintenance dose. This study explored the correlations of VKORC1–1639 G/A, 1173 C/T and 497 T/G genetic polymorphisms with warfarin maintenance dose requirement in patients undergoing cardiac valve replacement. Material/Methods A total of 298 patients undergoing cardiac valve replacement were recruited. During follow-up, clinical data were recorded. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was applied to detect VKORC1–1639 G/A, 1173 C/T and 497 T/G polymorphisms, and genotypes were analyzed. Results Correlations between warfarin maintenance dose and baseline characteristics revealed statistical significances of age, gender and operation methods with warfarin maintenance dose (all P<0.05). Warfarin maintenance dose in VKORC1–1639 G/A AG + GG carriers was obviously higher than in AA carriers (P<0.001). As compared with patients with TT genotype in VKORC1 1173 C/T, warfarin maintenance dose was apparently higher in patients with CT genotype (P<0.001). Linear regression analysis revealed that gender, operation method, method for heart valve replacement, as well as VKORC1–1639 G/A and 1173 C/T gene polymorphisms were significantly related to warfarin maintenance dose (all P<0.05). Conclusions VKORC1 gene polymorphisms are key genetic factors to affect individual differences in warfarin maintenance dose in patients undergoing cardiac valve replacement; meanwhile, gender, operation method and method for heart valve replacement might also be correlate with warfarin maintenance dose. PMID:26583785
Developing RCM Strategy for Hydrogen Fuel Cells Utilizing On Line E-Condition Monitoring
NASA Astrophysics Data System (ADS)
Baglee, D.; Knowles, M. J.
2012-05-01
Fuel cell vehicles are considered to be a viable solution to problems such as carbon emissions and fuel shortages for road transport. Proton Exchange Membrane (PEM) Fuel Cells are mainly used in this purpose because they can run at low temperatures and have a simple structure. Yet high maintenance costs and the inherent dangers of maintaining equipment using hydrogen are two main issues which need to be addressed. The development of appropriate and efficient strategies is currently lacking with regard to fuel cell maintenance. A Reliability Centered Maintenance (RCM) approach offers considerable benefit to the management of fuel cell maintenance since it includes an identification and consideration of the impact of critical components. Technological developments in e-maintenance systems, radio-frequency identification (RFID) and personal digital assistants (PDAs) have proven to satisfy the increasing demand for improved reliability, efficiency and safety. RFID technology is used to store and remotely retrieve electronic maintenance data in order to provide instant access to up-to-date, accurate and detailed information. The aim is to support fuel cell maintenance decisions by developing and applying a blend of leading-edge communications and sensor technology including RFID. The purpose of this paper is to review and present the state of the art in fuel cell condition monitoring and maintenance utilizing RCM and RFID technologies. Using an RCM analysis critical components and fault modes are identified. RFID tags are used to store the critical information, possible faults and their cause and effect. The relationship between causes, faults, symptoms and long term implications of fault conditions are summarized. Finally conclusions are drawn regarding suggested maintenance strategies and the optimal structure for an integrated, cost effective condition monitoring and maintenance management system.
Voils, Corrine I; Gierisch, Jennifer M; Olsen, Maren K; Maciejewski, Matthew L; Grubber, Janet; McVay, Megan A; Strauss, Jennifer L; Bolton, Jamiyla; Gaillard, Leslie; Strawbridge, Elizabeth; Yancy, William S
2014-09-01
Obesity is a significant public health problem. Although various lifestyle approaches are effective for inducing significant weight loss, few effective behavioral weight maintenance strategies have been identified. It has been proposed that behavior maintenance is a distinct state that involves different psychological processes and behavioral skills than initial behavior change. Previously, we created a conceptual model that distinguishes behavior initiation from maintenance. This model was used to generate Maintenance After Initiation of Nutrition TrAINing (MAINTAIN), an intervention to enhance weight loss maintenance following initiation. The effectiveness of MAINTAIN is being evaluated in an ongoing trial, the rationale and procedures of which are reported herein. Veterans aged ≤ 75 with body mass index ≥ 30 kg/m(2) participate in a 16-week, group-based weight loss program. Participants who lose ≥ 4 kg by the end of 16 weeks (target n = 230) are randomized 1:1 to receive (a) usual care for 56 weeks or (b) MAINTAIN, a theoretically-informed weight loss maintenance intervention for 40 weeks, followed by 16 weeks of no intervention contact. MAINTAIN involves 3 in-person group visits that transition to 8 individualized telephone calls with decreasing contact frequency. MAINTAIN focuses on satisfaction with outcomes, weight self-monitoring, relapse prevention, and social support. We hypothesize that, compared to usual care, MAINTAIN will result in at least 3.5 kg less regain and better relative levels of caloric intake and physical activity over 56 weeks, and that it will be cost-effective. If effective, MAINTAIN could serve as a model for redesigning existing weight loss programs. NCT01357551. Published by Elsevier Inc.
Mattos, Diego; Mateus, José Roberto; Merino, Eugenio
2012-01-01
The use of mind maps as a method of building knowledge, planning, organizing activities and ideas can be seen in the literature related to ergonomics. The results of such use are relevant and its use in academic area found. However, regarding to its use in industrial environments, studies can't not be found. With this scenario, and based on the perception of the ergonomist about the importance of using methods such as mind maps in support of human cognition, it seems pertinent to its use in industry sectors whose cognitive demand requires. Given these assumptions, this study aimed to apply the method of Mind Maps in Productive Maintenance sector of a Brazilian paper. The Productive Maintenance sector in the Paper Industry has an important contribution to operational performance. With practical Predictive Maintenance, Preventive Maintenance and Corrective Maintenance, the industry advocates to make the machines to produce paper is not to stop producing when they are programmed to do so. Among the practices cited, the Preventive Maintenance is one that leads to pre-determined intervals in order to reduce the possibility of placing the equipment in a condition below the required level of acceptance. Therefore, this article aims to propose using the tool "mental maps" in order to collaborate in planning and implementation of preventive maintenance activities in the sector of mechanical maintenance of a pulp and paper industry in southern Brazil. The study investigated the maintenance sector through its employees, who went through training about the tool and then use it and ergonomists company.
75 FR 46861 - Airworthiness Directives; Airbus Model A330-200 and -300 Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-04
... Maintenance Requirements (CMR) are given in Airbus A330 ALS Part 3, which is approved by the European Aviation Safety Agency (EASA). The revision 02 of Airbus A330 ALS Part 3 introduces more restrictive maintenance... Limitations Section (ALS). The airworthiness limitations applicable to the Certification Maintenance...
76 FR 64851 - Airworthiness Directives; Learjet Inc. Model 45 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-19
... Limitations Section (ALS) of the maintenance manual, which adds life-limits, revises life-limits, or adds.... Discussion We have reviewed the design approval holder's changes to the ALS of the maintenance manual, which... Labor cost Parts cost product operators Change ALS in maintenance manual.... 1 work-hour x $85 per $0...
Generalized Maintenance Trainer Simulator: Development of Hardware and Software. Final Report.
ERIC Educational Resources Information Center
Towne, Douglas M.; Munro, Allen
A general purpose maintenance trainer, which has the potential to simulate a wide variety of electronic equipments without hardware changes or new computer programs, has been developed and field tested by the Navy. Based on a previous laboratory model, the Generalized Maintenance Trainer Simulator (GMTS) is a relatively low cost trainer that…
Analysis of EA-18G Growler Engine Maintenance at Naval Air Station Whidbey Island, WA
2013-05-30
The aviation maintenance community considers the NAMP its bible . “The NAMP applies to all organizations operating or supporting Navy and Marine Corps...the present scenario and this will increase to 114, which is the total number of aircraft at the completion of the acquisition process in year 2018 ...increasing by 12 per year until 2018 where eight will complete the acquisition). The cost of the F414-GE-400 engine is about $3.7 million
Logistics Operations Management Center: Maintenance Support Baseline (LOMC-MSB)
NASA Technical Reports Server (NTRS)
Kurrus, R.; Stump, F.
1995-01-01
The Logistics Operations Management Center Maintenance Support Baseline is defined. A historical record of systems, applied to and deleted from, designs in support of future management and/or technical analysis is provided. All Flight elements, Ground Support Equipment, Facility Systems and Equipment and Test Support Equipment for which LOMC has responsibilities at Kennedy Space Center and other locations are listed. International Space Station Alpha Program documentation is supplemented. The responsibility of the Space Station Launch Site Support Office is established.
Characterizing and Assessing a Large-Scale Software Maintenance Organization
NASA Technical Reports Server (NTRS)
Briand, Lionel; Melo, Walcelio; Seaman, Carolyn; Basili, Victor
1995-01-01
One important component of a software process is the organizational context in which the process is enacted. This component is often missing or incomplete in current process modeling approaches. One technique for modeling this perspective is the Actor-Dependency (AD) Model. This paper reports on a case study which used this approach to analyze and assess a large software maintenance organization. Our goal was to identify the approach's strengths and weaknesses while providing practical recommendations for improvement and research directions. The AD model was found to be very useful in capturing the important properties of the organizational context of the maintenance process, and aided in the understanding of the flaws found in this process. However, a number of opportunities for extending and improving the AD model were identified. Among others, there is a need to incorporate quantitative information to complement the qualitative model.
36 CFR § 1222.10 - How should agencies apply the statutory definition of Federal records?
Code of Federal Regulations, 2013 CFR
2013-07-01
... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true How should agencies apply the statutory definition of Federal records? § 1222.10 Section § 1222.10 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS...
36 CFR § 1222.2 - What definitions apply to this part?
Code of Federal Regulations, 2013 CFR
2013-07-01
... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true What definitions apply to this part? § 1222.2 Section § 1222.2 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT CREATION AND MAINTENANCE OF FEDERAL RECORDS Identifying Federal Records § 1222...
40 CFR 65.3 - Compliance with standards and operation and maintenance requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
...)(4)(i) and (ii) do not apply to Group 2A or Group 2B process vents. Compliance with design, equipment... include, but are not limited to, air pollution control technologies, recovery technologies, work practices... control devices are not required but may be used if available. This paragraph (a)(3) does not apply to...
40 CFR 65.3 - Compliance with standards and operation and maintenance requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
...)(4)(i) and (ii) do not apply to Group 2A or Group 2B process vents. Compliance with design, equipment... include, but are not limited to, air pollution control technologies, recovery technologies, work practices... control devices are not required but may be used if available. This paragraph (a)(3) does not apply to...
Know how to maximize maintenance spending
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carrino, A.J.; Jones, R.B.; Platt, W.E.
Solomon has developed a methodology to determine a large optimum point where availability meets maintenance spending for Powder River Basin (PRB) coal-fired units. Using a database of sufficient size and composition across various operating ranges, Solomon generated an algorithm that predicts the relationship between maintenance spending and availability. Coupling this generalized algorithm with a unit-specific market-loss curve determines the optimum spending for a facility. The article presents the results of the analysis, how this methodology can be applied to develop optimum operating and financial targets for specific units and markets and a process to achieve those targets. It also describesmore » how this methodology can be used for other types of fossil-fired technologies and future enhancements to the analysis. 5 figs.« less
Coherence and recurrency: maintenance, control and integration in working memory
Raffone, Antonino
2007-01-01
Working memory (WM), including a ‘central executive’, is used to guide behavior by internal goals or intentions. We suggest that WM is best described as a set of three interdependent functions which are implemented in the prefrontal cortex (PFC). These functions are maintenance, control of attention and integration. A model for the maintenance function is presented, and we will argue that this model can be extended to incorporate the other functions as well. Maintenance is the capacity to briefly maintain information in the absence of corresponding input, and even in the face of distracting information. We will argue that maintenance is based on recurrent loops between PFC and posterior parts of the brain, and probably within PFC as well. In these loops information can be held temporarily in an active form. We show that a model based on these structural ideas is capable of maintaining a limited number of neural patterns. Not the size, but the coherence of patterns (i.e., a chunking principle based on synchronous firing of interconnected cell assemblies) determines the maintenance capacity. A mechanism that optimizes coherent pattern segregation, also poses a limit to the number of assemblies (about four) that can concurrently reverberate. Top-down attentional control (in perception, action and memory retrieval) can be modelled by the modulation and re-entry of top-down information to posterior parts of the brain. Hierarchically organized modules in PFC create the possibility for information integration. We argue that large-scale multimodal integration of information creates an ‘episodic buffer’, and may even suffice for implementing a central executive. PMID:17901994
76 FR 31457 - Airworthiness Directives; Diamond Aircraft Industries GmbH Model DA 42 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-01
... Airworthiness Directives; Diamond Aircraft Industries GmbH Model DA 42 Airplanes AGENCY: Federal Aviation... reportedly found on DA 42 Main Landing Gear (MLG) Damper-to-Trailing Arm joints during standard maintenance... DA 42 Main Landing Gear (MLG) Damper-to-Trailing Arm joints during standard maintenance. Depending on...
NASA Astrophysics Data System (ADS)
Zhong, Shuya; Pantelous, Athanasios A.; Beer, Michael; Zhou, Jian
2018-05-01
Offshore wind farm is an emerging source of renewable energy, which has been shown to have tremendous potential in recent years. In this blooming area, a key challenge is that the preventive maintenance of offshore turbines should be scheduled reasonably to satisfy the power supply without failure. In this direction, two significant goals should be considered simultaneously as a trade-off. One is to maximise the system reliability and the other is to minimise the maintenance related cost. Thus, a non-linear multi-objective programming model is proposed including two newly defined objectives with thirteen families of constraints suitable for the preventive maintenance of offshore wind farms. In order to solve our model effectively, the nondominated sorting genetic algorithm II, especially for the multi-objective optimisation is utilised and Pareto-optimal solutions of schedules can be obtained to offer adequate support to decision-makers. Finally, an example is given to illustrate the performances of the devised model and algorithm, and explore the relationships of the two targets with the help of a contrast model.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-27
... To Refer to Latest Revision of the Aircraft Maintenance Manual (AMM) Great Lakes stated that the...--Description and Operation, of Chapter 28, Fuel, the EMBRAER EMB120 Brasilia Aircraft Maintenance Manual, MM... Operation, of Chapter 28, Fuel, of the EMBRAER EMB120 Brasilia Aircraft Maintenance Manual, Revision 24...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-17
... BD- 100 Time Limits/Maintenance Checks. The actions described in this service information are... Challenger 300 BD-100 Time Limits/Maintenance Checks. (1) For the new tasks identified in Bombardier TR 5-2... Requirements,'' in Part 2 of Chapter 5 of Bombardier Challenger 300 BD-100 Time Limits/ Maintenance Checks...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-05
... Bombardier Challenger 300 BD-100 Time Limits/Maintenance Checks Manual. For this task, the initial compliance..., of Part 2, of the Bombardier Challenger 300 BD-100 Time Limits/Maintenance Checks Manual, the general.../Maintenance Checks Manual, provided that the relevant information in the general revision is identical to that...
ERIC Educational Resources Information Center
Hackett, E. Raymond; Morgan, Thomas
1996-01-01
Examines strategies for conducting expected and deferred maintenance of small colleges for use as a model that may be adapted to other educational settings. Investigates the relationship between total education and general expenditures and expenditures for operation of plant and maintenance, and looks at using the annual budget to meet expected…
ERIC Educational Resources Information Center
North Carolina State Dept. of Community Colleges, Raleigh.
This articulation instructional objective guide for automotive mechanics contains summary information on fifteen blocks (courses) of instruction. They are introduction to automotive technology; lubrication and vehicle operating maintenance; cooling system maintenance and repair; automobile heater maintenance and repair; braking system maintenance…
Commentary on the shifting processes model: a conceptual model for weight management.
Pagoto, Sherry; Rodrigues, Stephanie
2013-12-01
Macchi and colleagues propose a theoretical model that merges concepts from the biopsychosocial model and family systems theory to produce a broader framework for understanding weight loss and maintenance (see record 2013-28564-001). The Shifting Processes Model views individual weight loss and maintenance in the context of family dynamics, including family eating and exercise habits, home environment, and family relationships. The authors reason that traditional models put the burden of change on the individual rather than the family system, when the latter is an important context of individual behavior.
Leveraging annotation-based modeling with Jump.
Bergmayr, Alexander; Grossniklaus, Michael; Wimmer, Manuel; Kappel, Gerti
2018-01-01
The capability of UML profiles to serve as annotation mechanism has been recognized in both research and industry. Today's modeling tools offer profiles specific to platforms, such as Java, as they facilitate model-based engineering approaches. However, considering the large number of possible annotations in Java, manually developing the corresponding profiles would only be achievable by huge development and maintenance efforts. Thus, leveraging annotation-based modeling requires an automated approach capable of generating platform-specific profiles from Java libraries. To address this challenge, we present the fully automated transformation chain realized by Jump, thereby continuing existing mapping efforts between Java and UML by emphasizing on annotations and profiles. The evaluation of Jump shows that it scales for large Java libraries and generates profiles of equal or even improved quality compared to profiles currently used in practice. Furthermore, we demonstrate the practical value of Jump by contributing profiles that facilitate reverse engineering and forward engineering processes for the Java platform by applying it to a modernization scenario.
Hydrological impacts of climate change on the Tejo and Guadiana Rivers
NASA Astrophysics Data System (ADS)
Kilsby, C. G.; Tellier, S. S.; Fowler, H. J.; Howels, T. R.
2007-05-01
A distributed daily rainfall runoff model is applied to the Tejo and Guadiana river basins in Spain and Portugal to simulate the effects of climate change on runoff production, river flows and water resource availability with results aggregated to the monthly level. The model is calibrated, validated and then used for a series of climate change impact assessments for the period 2070 2100. Future scenarios are derived from the HadRM3H regional climate model (RCM) using two techniques: firstly a bias-corrected RCM output, with monthly mean correction factors calculated from observed rainfall records; and, secondly, a circulation-pattern-based stochastic rainfall model. Major reductions in rainfall and streamflow are projected throughout the year; these results differ from those for previous studies where winter increases are projected. Despite uncertainties in the representation of heavily managed river systems, the projected impacts are serious and pose major threats to the maintenance of bipartite water treaties between Spain and Portugal and the supply of water to urban and rural regions of Portugal.
Simple Model for Identifying Critical Regions in Atrial Fibrillation
NASA Astrophysics Data System (ADS)
Christensen, Kim; Manani, Kishan A.; Peters, Nicholas S.
2015-01-01
Atrial fibrillation (AF) is the most common abnormal heart rhythm and the single biggest cause of stroke. Ablation, destroying regions of the atria, is applied largely empirically and can be curative but with a disappointing clinical success rate. We design a simple model of activation wave front propagation on an anisotropic structure mimicking the branching network of heart muscle cells. This integration of phenomenological dynamics and pertinent structure shows how AF emerges spontaneously when the transverse cell-to-cell coupling decreases, as occurs with age, beyond a threshold value. We identify critical regions responsible for the initiation and maintenance of AF, the ablation of which terminates AF. The simplicity of the model allows us to calculate analytically the risk of arrhythmia and express the threshold value of transversal cell-to-cell coupling as a function of the model parameters. This threshold value decreases with increasing refractory period by reducing the number of critical regions which can initiate and sustain microreentrant circuits. These biologically testable predictions might inform ablation therapies and arrhythmic risk assessment.
10 CFR 1044.03 - What definitions apply to this part?
Code of Federal Regulations, 2010 CFR
2010-01-01
... information” in the Atomic Energy Act). Contractor means any industrial, educational, commercial or other... activities means activities of DOE engaged in support of: (1) The production, testing, sampling, maintenance...
10-MWe solar-thermal central-receiver pilot plant. Operating and maintenance manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-08-01
Information required to perform the initial program loading and operation of the Heliostat Array Controller (HAC) is provided. Operating activities are described as required for heliostat control. All computer console command steps, from power up to power down are described. Detailed steps are provided to wake up the system and direct heliostat beams to standby, on target, standby to stow and power down. Maintenance requirements (preventive and corrective), reparability (reparable - non-reparable decisions), spares identification, spares storage location, replacement levels, replacement location and repair location are established. Individual system breakdown block diagrams are provided for each system/assembly/subassembly. Maintenance and repairmore » description sheets are provided for each maintenance significant item. The manual provides support of the following equipment: (a) helostat assembly; (b) heliostat control assembly; and (c) maintenance and installation equipment. The safety requirements for the operating and maintenance functions are established. These procedures will assist in eliminating or controlling the accident potentials caused by human error, environment, or component malfunctions or interactions that could result in major injury or fatality to operating or visiting personnel, or damage to subsystem components or support equipment. These procedures are for normal and test operating conditions and emergency situations, and apply to all Martin Marietta Corporation, governmental, operating and visitor personnel. (LEW)« less
Virgili, Annarosa; Minghetti, Sara; Borghi, Alessandro; Corazza, Monica
2013-04-01
The chronic and relapsing nature of vulvar lichen sclerosus (VLS) represents a challenge for its long-term management after an effective treatment with topical corticosteroids. To compare the effect of topical vitamin E with that of an emollient in reducing the risk of VLS relapse over a 52-week maintenance treatment. 156 patients with VLS were enrolled in a 12-week active treatment phase on topical 0.1% mometasone furoate ointment once daily. Those who achieved disease remission entered a 52-week maintenance phase in which patients were randomized to apply either an emollient or topical vitamin E once daily. 80 patients entered the maintenance phase. At 52 weeks, for the vitamin E maintenance group, the cumulative crude relapse rate was 27.8% and the cumulative modified crude relapse rate was 55.6%. For the emollient maintenance group, the cumulative crude relapse rate was 22.7% and the cumulative modified crude relapse rate was 50.0%. The median time to relapse was 20 weeks for the vitamin E group and 18.7 weeks for the emollient group. Once VLS has been stabilized with topical corticosteroids, long-term treatment with both vitamin E and emollients may be considered in maintain LS remission.
Evaluation System and Implementation Countermeasure of Automobile Green Maintenance
NASA Astrophysics Data System (ADS)
Zhang, Fei; Xie, Xinxin; Yan, Chaoyong
2018-01-01
Green maintenance research is in the beginning of our country, the work is being explored. Based on the existing research results at home and abroad, this paper learns and draws lessons from the experiences and lessons of foreign advanced countries and domestic advanced enterprises. In the face of the challenges brought by economic development and energy saving and emission reduction, this paper discusses the green maintenance theory and security system, And the research status of green maintenance content and system at home and abroad, through the deletion and selection of green maintenance index, through the AHP method to determine the green evaluation criteria, and the introduction of C equivalent evaluation system, the use of fuzzy synthesis Evaluation method to build a green maintenance evaluation model, and the actual validation, put forward the implementation of green maintenance feasibility programs and related security recommendations, vehicle maintenance enterprises to carry out green maintenance, improve business efficiency and reduce environmental management costs to provide theoretical basis. And to achieve effective reduction of environmental pollution, reduce maintenance costs of the target, a reasonable promotion of maintenance and environmental protection and sustainable development. Promote green maintenance from research to practice, from the laboratory to the maintenance of enterprises, from the pilot to the overall development and transformation.
2013-10-21
depend on the quality of allocating resources. This work uses a reliability model of system and environmental covariates incorporating information at...state space. Further, the use of condition variables allows for the direct modeling of maintenance impact with the assumption that a nominal value ... value ), the model in the application of aviation maintenance can provide a useful estimation of reliability at multiple levels. Adjusted survival
Modernizing a Preventive Maintenance Strategy for Facility and Infrastructure Maintenance
2009-03-01
White Sands Missle Range. Advanced Simulations Technology Conference. Orlando: Society for Modeling and Simulation International. Sheu, C...consisted of developing a model to bridge the gap between the current RWP and what it needs to become. It resulted in eight Focus Areas (FAs) that were...Additionally, the Air Force has a model for modernizing its RWP. v Acknowledgements I’d like to thank my family, classmates, advisor, thesis
Human-Technology Centric In Cyber Security Maintenance For Digital Transformation Era
NASA Astrophysics Data System (ADS)
Ali, Firkhan Ali Bin Hamid; Zalisham Jali, Mohd, Dr
2018-05-01
The development of the digital transformation in the organizations has become more expanding in these present and future years. This is because of the active demand to use the ICT services among all the organizations whether in the government agencies or private sectors. While digital transformation has led manufacturers to incorporate sensors and software analytics into their offerings, the same innovation has also brought pressure to offer clients more accommodating appliance deployment options. So, their needs a well plan to implement the cyber infrastructures and equipment. The cyber security play important role to ensure that the ICT components or infrastructures execute well along the organization’s business successful. This paper will present a study of security management models to guideline the security maintenance on existing cyber infrastructures. In order to perform security model for the currently existing cyber infrastructures, combination of the some security workforces and security process of extracting the security maintenance in cyber infrastructures. In the assessment, the focused on the cyber security maintenance within security models in cyber infrastructures and presented a way for the theoretical and practical analysis based on the selected security management models. Then, the proposed model does evaluation for the analysis which can be used to obtain insights into the configuration and to specify desired and undesired configurations. The implemented cyber security maintenance within security management model in a prototype and evaluated it for practical and theoretical scenarios. Furthermore, a framework model is presented which allows the evaluation of configuration changes in the agile and dynamic cyber infrastructure environments with regard to properties like vulnerabilities or expected availability. In case of a security perspective, this evaluation can be used to monitor the security levels of the configuration over its lifetime and to indicate degradations.
Sheppy, Michael; Beach, A.; Pless, Shanti
2016-08-09
Modern buildings are complex energy systems that must be controlled for energy efficiency. The Research Support Facility (RSF) at the National Renewable Energy Laboratory (NREL) has hundreds of controllers -- computers that communicate with the building's various control systems -- to control the building based on tens of thousands of variables and sensor points. These control strategies were designed for the RSF's systems to efficiently support research activities. Many events that affect energy use cannot be reliably predicted, but certain decisions (such as control strategies) must be made ahead of time. NREL researchers modeled the RSF systems to predict how they might perform. They then monitor these systems to understand how they are actually performing and reacting to the dynamic conditions of weather, occupancy, and maintenance.
Camos, Valérie; Barrouillet, Pierre
2014-01-01
Working memory is the structure devoted to the maintenance of information at short term during concurrent processing activities. In this respect, the question regarding the nature of the mechanisms and systems fulfilling this maintenance function is of particular importance and has received various responses in the recent past. In the time-based resource-sharing (TBRS) model, we suggest that only two systems sustain the maintenance of information at the short term, counteracting the deleterious effect of temporal decay and interference. A non-attentional mechanism of verbal rehearsal, similar to the one described by Baddeley in the phonological loop model, uses language processes to reactivate phonological memory traces. Besides this domain-specific mechanism, an executive loop allows the reconstruction of memory traces through an attention-based mechanism of refreshing. The present paper reviews evidence of the involvement of these two independent systems in the maintenance of verbal memory items. PMID:25426049
Lin28b is sufficient to drive liver cancer and necessary for its maintenance in murine models
Nguyen, Liem H.; Robinton, Daisy A.; Seligson, Marc; Wu, Linwei; Li, Lin; Rakheja, Dinesh; Comerford, Sarah; Ramezani, Saleh; Sun, Xiankai; Parikh, Monisha; Yang, Erin; Powers, John T.; Shinoda, Gen; Shah, Samar; Hammer, Robert; Daley, George Q.; Zhu, Hao
2014-01-01
SUMMARY Lin28a/b are RNA-binding proteins that influence stem cell maintenance, metabolism, and oncogenesis. Poorly differentiated, aggressive cancers often overexpress Lin28, but its role in tumor initiation or maintenance has not been definitively addressed. We report that LIN28B overexpression is sufficient to initiate hepatoblastoma and hepatocellular carcinoma in murine models. We also detected Lin28b overexpression in MYC-driven hepatoblastomas, and liver-specific deletion of Lin28a/b reduced tumor burden, extended latency, and prolonged survival. Both intravenous siRNA against Lin28b and conditional Lin28b deletion reduced tumor burden and prolonged survival. Igf2bp proteins are upregulated and Igf2bp3 is required in the context of LIN28B overexpression to promote growth. Thus, multiple murine models demonstrate that Lin28b is both sufficient to initiate liver cancer and necessary for its maintenance. PMID:25117712
Raman, Jayanthi; Smith, Evelyn; Hay, Phillipa
2013-01-01
Psychological distress and deficits in executive functioning are likely to be important barriers to effective weight loss maintenance. The purpose of this paper is twofold. First, in the light of recent evidence in the fields of neuropsychology and obesity, particularly on the deficits in the executive function in overweight and obese individuals, a conceptual and theoretical framework of obesity maintenance is introduced by way of a clinical obesity maintenance model (COMM). It is argued that psychological variables, that of habitual cluster Behaviors, emotional dysregulation, mood, and health literacy, interact with executive functioning and impact on the overeating/binge eating behaviors of obese individuals. Second, cognizant of this model, it is argued that the focus of obesity management should be extended to include a broader range of maintaining mechanisms, including but not limited to cognitive deficits. Finally, a discussion on potential future directions in research and practice using the COMM is provided.
Lineage Selection and the Maintenance of Sex
de Vienne, Damien M.; Giraud, Tatiana; Gouyon, Pierre-Henri
2013-01-01
Sex predominates in eukaryotes, despite its short-term disadvantage when compared to asexuality. Myriad models have suggested that short-term advantages of sex may be sufficient to counterbalance its twofold costs. However, despite decades of experimental work seeking such evidence, no evolutionary mechanism has yet achieved broad recognition as explanation for the maintenance of sex. We explore here, through lineage-selection models, the conditions favouring the maintenance of sex. In the first model, we allowed the rate of transition to asexuality to evolve, to determine whether lineage selection favoured species with the strongest constraints preventing the loss of sex. In the second model, we simulated more explicitly the mechanisms underlying the higher extinction rates of asexual lineages than of their sexual counterparts. We linked extinction rates to the ecological and/or genetic features of lineages, thereby providing a formalisation of the only figure included in Darwin's “The origin of species”. Our results reinforce the view that the long-term advantages of sex and lineage selection may provide the most satisfactory explanations for the maintenance of sex in eukaryotes, which is still poorly recognized, and provide figures and a simulation website for training and educational purposes. Short-term benefits may play a role, but it is also essential to take into account the selection of lineages for a thorough understanding of the maintenance of sex. PMID:23825582
Kissel, R C; Whitman, T L; Reid, D H
1983-01-01
Although considerable attention has been given to the development of institutional staff training and management programs, the generalized effects of such programs on staff and resident behavior have seldom been examined. This study evaluated a program for teaching institutional staff behavioral training and self-management skills during self-care teaching sessions with severely and profoundly retarded residents. Following baseline observations in three self-care situations (toothbrushing, haircombing, handwashing), four direct care staff were sequentially taught to use verbal instruction, physical guidance, and contingent reinforcement in the toothbrushing program. During maintenance, staff were simultaneously taught to record, graph, and evaluate resident and their own behavior in the toothbrushing sessions. Staff were taught use of the training and self-management skills through a sequence of written instructions, videotaped and live modeling, rehearsal, and videotaped feedback. Observer presence and experimenter supervision were gradually decreased during the maintenance condition. Results indicated that during training and maintenance staff: (a) learned to use the training skills appropriately and consistently in the example situation (toothbrushing); (b) applied the skills in the generalization situations (haircombing and handwashing); and thereafter (c) maintained consistent and appropriate use of the skills with infrequent supervision. In addition, important changes in retarded residents' independent self-care responding occurred as staff training skills developed. Results are discussed in terms of their implications for future research and continued development of effective staff training and management programs. PMID:6654771
Fleary, Sasha A; Tagorda, M; Kim, S; Rathke, M; Nigg, C R
2018-06-01
Filipino adolescents are underrepresented in obesity research, although Filipinos are the second largest Asian-American and Pacific Islander (AAPI) subpopulation in the USA. An understanding of how well the theories of behavior change apply to Filipino and other AAPI adolescents is critical to addressing obesogenic behaviors in these groups. This study aimed to validate the transtheoretical model of behavior change (TTM) for physical activity (PA) and fruit and vegetable intake (FV) among a majority Filipino adolescent population. Adolescents in grades 9-11 (N = 159, 82.4% female) completed measures of PA and FV behaviors and PA and FV stages of change. One-way ANOVAs and Tukey's HSD post hoc tests were computed to assess the validity of the PA and FV stages of change with the respective behaviors. There was a significant effect for fruit (action > contemplation, preparation) and vegetable (maintenance, action > contemplation) intakes across the FV stages of change. There was a significant effect of strenuous PA (precontemplation/contemplation, preparation < action < maintenance) and moderate PA (precontemplation/contemplation < action, maintenance) across the PA stages of change. Some variability in associations emerged when the sample was stratified by gender. This study provides validity evidence for the TTM stages of change for FV and PA among Filipino and other AAPI adolescents. This validation, in turn, extends the generalizability of the stages of change construct to include this ethnic group and replicates other adolescent studies.
8 CFR 1214.1 - Review of requirements for admission, extension, and maintenance of status.
Code of Federal Regulations, 2014 CFR
2014-01-01
...) of the Act. Upon application for admission, the alien shall present a valid passport and valid visa... present a passport only if requested to do so by the Service. The passport of an alien applying for... conditions of his or her admission. The passport of an alien applying for extension of stay shall be valid at...
8 CFR 1214.1 - Review of requirements for admission, extension, and maintenance of status.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) of the Act. Upon application for admission, the alien shall present a valid passport and valid visa... present a passport only if requested to do so by the Service. The passport of an alien applying for... conditions of his or her admission. The passport of an alien applying for extension of stay shall be valid at...
8 CFR 1214.1 - Review of requirements for admission, extension, and maintenance of status.
Code of Federal Regulations, 2011 CFR
2011-01-01
...) of the Act. Upon application for admission, the alien shall present a valid passport and valid visa... present a passport only if requested to do so by the Service. The passport of an alien applying for... conditions of his or her admission. The passport of an alien applying for extension of stay shall be valid at...
8 CFR 1214.1 - Review of requirements for admission, extension, and maintenance of status.
Code of Federal Regulations, 2012 CFR
2012-01-01
...) of the Act. Upon application for admission, the alien shall present a valid passport and valid visa... present a passport only if requested to do so by the Service. The passport of an alien applying for... conditions of his or her admission. The passport of an alien applying for extension of stay shall be valid at...
8 CFR 1214.1 - Review of requirements for admission, extension, and maintenance of status.
Code of Federal Regulations, 2013 CFR
2013-01-01
...) of the Act. Upon application for admission, the alien shall present a valid passport and valid visa... present a passport only if requested to do so by the Service. The passport of an alien applying for... conditions of his or her admission. The passport of an alien applying for extension of stay shall be valid at...
40 CFR 63.1443 - When do I have to comply with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... affected source and its initial startup date is on or before June 12, 2002, you must comply with each... applies to you by June 12, 2002. (c) If you have a new affected source and its initial startup date is... operation and maintenance requirement in this subpart that applies to you upon initial startup. (d) If your...
40 CFR 63.1443 - When do I have to comply with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... affected source and its initial startup date is on or before June 12, 2002, you must comply with each... applies to you by June 12, 2002. (c) If you have a new affected source and its initial startup date is... operation and maintenance requirement in this subpart that applies to you upon initial startup. (d) If your...
40 CFR 63.1443 - When do I have to comply with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... affected source and its initial startup date is on or before June 12, 2002, you must comply with each... applies to you by June 12, 2002. (c) If you have a new affected source and its initial startup date is... operation and maintenance requirement in this subpart that applies to you upon initial startup. (d) If your...
Physical activity among adults with obesity: testing the Health Action Process Approach.
Parschau, Linda; Barz, Milena; Richert, Jana; Knoll, Nina; Lippke, Sonia; Schwarzer, Ralf
2014-02-01
This study tested the applicability of the Health Action Process Approach (HAPA) in a sample of obese adults in the context of physical activity. Physical activity was assessed along with motivational and volitional variables specified in the HAPA (motivational self-efficacy, outcome expectancies, risk perception, intention, maintenance self-efficacy, action planning, coping planning, recovery self-efficacy, social support) in a sample of 484 obese men and women (body mass index ≥ 30 kg/m2). Applying structural equation modeling, the fit of the HAPA model was satisfactory-χ²(191) = 569.93, p < .05, χ²/df = 2.98, comparative fit index = .91, normed-fit index = .87, and root mean square error of approximation = .06 (90% CI = .06, .07)-explaining 30% of the variance in intention and 18% of the variance in physical activity. Motivational self-efficacy, outcome expectancies, and social support were related to intention. An association between maintenance self-efficacy and coping planning was found. Recovery self-efficacy and social support were associated with physical activity. No relationships were found between risk perception and intention and between planning and physical activity. The assumptions derived from the HAPA were partly confirmed and the HAPA may, therefore, constitute a theoretical backdrop for intervention designs to promote physical activity in adults with obesity. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Alternate approach slab reinforcement.
DOT National Transportation Integrated Search
2010-06-01
The upper mat of reinforcing steel, in exposed concrete bridge approach slabs, is prone to corrosion damage. Chlorides applied to the highways : for winter maintenance can penetrate this concrete layer. Eventually chlorides reach the steel and begin ...
29 CFR 784.141 - Examples of nonexempt employees.
Code of Federal Regulations, 2010 CFR
2010-07-01
... “marketing” or “distributing” work like that described in § 784.155), custodial, maintenance, watching, and.... On like principle, the exemption may apply to a watchman whose services are required during...
77 FR 12037 - Information Collection; Submission for OMB Review, Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-28
... apply for AmeriCorps State and National funding. Type of Review: Renewal. Agency: Corporation for...,696 hours. Total Burden Cost (capital/startup): None. Total Burden Cost (operating/maintenance): None...
Multiple hypothesis tracking for the cyber domain
NASA Astrophysics Data System (ADS)
Schwoegler, Stefan; Blackman, Sam; Holsopple, Jared; Hirsch, Michael J.
2011-09-01
This paper discusses how methods used for conventional multiple hypothesis tracking (MHT) can be extended to domain-agnostic tracking of entities from non-kinematic constraints such as those imposed by cyber attacks in a potentially dense false alarm background. MHT is widely recognized as the premier method to avoid corrupting tracks with spurious data in the kinematic domain but it has not been extensively applied to other problem domains. The traditional approach is to tightly couple track maintenance (prediction, gating, filtering, probabilistic pruning, and target confirmation) with hypothesis management (clustering, incompatibility maintenance, hypothesis formation, and Nassociation pruning). However, by separating the domain specific track maintenance portion from the domain agnostic hypothesis management piece, we can begin to apply the wealth of knowledge gained from ground and air tracking solutions to the cyber (and other) domains. These realizations led to the creation of Raytheon's Multiple Hypothesis Extensible Tracking Architecture (MHETA). In this paper, we showcase MHETA for the cyber domain, plugging in a well established method, CUBRC's INFormation Engine for Real-time Decision making, (INFERD), for the association portion of the MHT. The result is a CyberMHT. We demonstrate the power of MHETA-INFERD using simulated data. Using metrics from both the tracking and cyber domains, we show that while no tracker is perfect, by applying MHETA-INFERD, advanced nonkinematic tracks can be captured in an automated way, perform better than non-MHT approaches, and decrease analyst response time to cyber threats.
ERIC Educational Resources Information Center
West, Amy E.; Henry, David B.; Pavuluri, Mani N.
2007-01-01
Objective: The chronic and refractory course of pediatric bipolar disorder merits the study of adjunctive psychosocial interventions designed to facilitate long-term improvements. The objective of this study is to conduct a pilot study of a maintenance model of the child- and family-focused cognitive-behavioral therapy program (CFF-CBT), which…
NASA Technical Reports Server (NTRS)
Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin
2014-01-01
Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.
NASA Technical Reports Server (NTRS)
Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin
2014-01-01
Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a recirculating control loop which had no water quality maintenance. Results show that periodic water maintenance can improve performance of the SWME. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage of this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing sublimator technology. The driver for the evaluation of water recirculation maintenance components was to enhance the robustness of the SWME through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A patented bed design that was developed for a United Technologies Aerospace System military application provided a low pressure drop means for water maintenance in the SWME recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for the ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.
A review of AirQ Models and their applications for forecasting the air pollution health outcomes.
Oliveri Conti, Gea; Heibati, Behzad; Kloog, Itai; Fiore, Maria; Ferrante, Margherita
2017-03-01
Even though clean air is considered as a basic requirement for the maintenance of human health, air pollution continues to pose a significant health threat in developed and developing countries alike. Monitoring and modeling of classic and emerging pollutants is vital to our knowledge of health outcomes in exposed subjects and to our ability to predict them. The ability to anticipate and manage changes in atmospheric pollutant concentrations relies on an accurate representation of the chemical state of the atmosphere. The task of providing the best possible analysis of air pollution thus requires efficient computational tools enabling efficient integration of observational data into models. A number of air quality models have been developed and play an important role in air quality management. Even though a large number of air quality models have been discussed or applied, their heterogeneity makes it difficult to select one approach above the others. This paper provides a brief review on air quality models with respect to several aspects such as prediction of health effects.
A Delphi Study of Aviation Maintenance Experts' Recommendations for a Model School Curriculum
ERIC Educational Resources Information Center
Dyen, Fred D.
2017-01-01
The program described in this paper is the essential first step in reviving and reinitiating the delivery of aviation maintenance technology instruction. The demand for aviation maintenance technicians (AMTs) is rapidly increasing and there is a need to provide as many as 679,000 AMTs over the next 20 years (Boeing, 2016). Given the high cost of…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-22
... (Low Stage Bleed Check Valve) specified in Section 1 of the EMBRAER 170 Maintenance Review Board Report...-11-02-002 (Low Stage Bleed Check Valve), specified in Section 1 of the EMBRAER 170 Maintenance Review... Task 36-11-02-002 (Low Stage Bleed Check Valve) specified in Section 1 of the EMBRAER 170 Maintenance...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-04
... maintenance plan to include repetitive functional tests of the low-stage check valve. For certain other... program to include maintenance Task Number 36-11-02- 002 (Low Stage Bleed Check Valve), specified in... Check Valve) in Section 1 of the EMBRAER 170 Maintenance Review Board Report MRB-1621. Issued in Renton...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-18
... amended the Airworthiness Limitation Section (ALS) of the Operation & Maintenance Manual OM-02-02 to... shutdowns of the engine(s). TAE has also amended the ALS of the Operation & Maintenance Manual OM- 02-01 to...-E000702 and has amended the Airworthiness Limitation Section (ALS) of the Operation & Maintenance Manual...
Elderly health beliefs, attitudes, and maintenance.
Jensen, J; Counte, M A; Glandon, G L
1992-07-01
Why older persons engage in varying amounts of health maintenance activity is becoming both an increasingly important policy issue and a topic of interest to health services researchers. Such activity may help the elderly to delay the onset of the health-related problems associated with aging, maintain if not improve their functional abilities, and perhaps improve their quality of life. Using a conceptual model largely based upon the health belief model, this study sought to examine predictors of variability of health maintenance activity among older persons. The project included cross-sectional data drawn from the first phase of a multiyear panel study of elderly community residents. Results of ordinary least-squares and logistic regression analyses of seven types of health maintenance activity suggest that health beliefs are an important consideration but that other variables, namely, type of insurance plan and select sociodemographic factors, also had significant impacts. Another consistent finding was that each of the types of health maintenance activity was associated with different types of predictor variables. These findings suggest that in order for levels of health maintenance activity to be increased, intervention programs need to be targeted toward specific types of health beliefs and need to take into account the importance of social differences.
Chiu, Ming-Chuan; Hsieh, Min-Chih
2016-05-01
The purposes of this study were to develop a latent human error analysis process, to explore the factors of latent human error in aviation maintenance tasks, and to provide an efficient improvement strategy for addressing those errors. First, we used HFACS and RCA to define the error factors related to aviation maintenance tasks. Fuzzy TOPSIS with four criteria was applied to evaluate the error factors. Results show that 1) adverse physiological states, 2) physical/mental limitations, and 3) coordination, communication, and planning are the factors related to airline maintenance tasks that could be addressed easily and efficiently. This research establishes a new analytic process for investigating latent human error and provides a strategy for analyzing human error using fuzzy TOPSIS. Our analysis process complements shortages in existing methodologies by incorporating improvement efficiency, and it enhances the depth and broadness of human error analysis methodology. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Zeng, Xiaohui; Li, Jianhe; Peng, Liubao; Wang, Yunhua; Tan, Chongqing; Chen, Gannong; Wan, Xiaomin; Lu, Qiong; Yi, Lidan
2014-01-01
Maintenance gefitinib significantly prolonged progression-free survival (PFS) compared with placebo in patients from eastern Asian with locally advanced/metastatic non-small-cell lung cancer (NSCLC) after four chemotherapeutic cycles (21 days per cycle) of first-line platinum-based combination chemotherapy without disease progression. The objective of the current study was to evaluate the cost-effectiveness of maintenance gefitinib therapy after four chemotherapeutic cycle's stand first-line platinum-based chemotherapy for patients with locally advanced or metastatic NSCLC with unknown EGFR mutations, from a Chinese health care system perspective. A semi-Markov model was designed to evaluate cost-effectiveness of the maintenance gefitinib treatment. Two-parametric Weibull and Log-logistic distribution were fitted to PFS and overall survival curves independently. One-way and probabilistic sensitivity analyses were conducted to assess the stability of the model designed. The model base-case analysis suggested that maintenance gefitinib would increase benefits in a 1, 3, 6 or 10-year time horizon, with incremental $184,829, $19,214, $19,328, and $21,308 per quality-adjusted life-year (QALY) gained, respectively. The most sensitive influential variable in the cost-effectiveness analysis was utility of PFS plus rash, followed by utility of PFS plus diarrhoea, utility of progressed disease, price of gefitinib, cost of follow-up treatment in progressed survival state, and utility of PFS on oral therapy. The price of gefitinib is the most significant parameter that could reduce the incremental cost per QALY. Probabilistic sensitivity analysis indicated that the cost-effective probability of maintenance gefitinib was zero under the willingness-to-pay (WTP) threshold of $16,349 (3 × per-capita gross domestic product of China). The sensitivity analyses all suggested that the model was robust. Maintenance gefitinib following first-line platinum-based chemotherapy for patients with locally advanced/metastatic NSCLC with unknown EGFR mutations is not cost-effective. Decreasing the price of gefitinib may be a preferential choice for meeting widely treatment demands in China.
2012-06-15
Maintenance AFSCs ................................................................................................. 14 2. Variation Inflation Factors...total variability in the data. It is an indication of how much of the 20 variation in the data can be accounted for in the regression model. In... Variation Inflation Factors for each independent variable (predictor) as regressed against all of the other independent variables in the model. The
Navas-Carretero, Santiago; Holst, Claus; Saris, Wim H; van Baak, Marleen A; Jebb, Susan A; Kafatos, Anthony; Papadaki, Angeliki; Pfeiffer, Andreas F H; Handjieva-Darlenska, Teodora; Hlavaty, Petr; Stender, Steen; Larsen, Thomas M; Astrup, Arne; Martinez, J Alfredo
2016-01-01
Maintenance of weight loss and associated cardiovascular benefits after following energy-restricted diets is still a challenging field, and thorough investigation is needed. The present research aimed to determine the role of protein and gender in relation to two different intervention models related to food supply, in a weight maintenance trial. The DiOGenes trial was a long-term, multicenter, randomized, dietary intervention study, conducted in eight European countries (Clinical Trials.gov, NCT00390637), focusing on assessing the effectiveness of weight maintenance over 6 months. This secondary analysis intended to evaluate the different benefits for weight maintenance and cardiometabolic markers of two dietary advice delivery models: "shop + instruction intervention" vs "instruction-alone intervention," which were further categorized for gender and macronutrient intake. The weight maintenance intervention based on different macronutrient intake showed, independently of the advice delivery model, in both sexes that higher protein consumption was more effective for weight stability, showing better results in obese women (low protein: 1.65 kg in males and 0.73 Kg in females vs high protein: 1.45 kg in males and -0.93 Kg in females) . Measurements concerning cardiovascular risk markers from subjects on both structured models produced similar trends in the subsequent follow-up period, with a lower rebound in women for most of the markers analyzed. The reported dietary benefits for weight sustainability should be ascribed to the macronutrient distribution (higher protein diets) rather than to the structured mode of delivery. Higher weight regain in males was noted, as well as a metabolic divergence attributable to the sex, with a better biochemical outcome in women.
Risk mitigation strategies for operations and maintenance activities.
DOT National Transportation Integrated Search
2012-04-01
The objective of this research was to investigate the application of integrated risk modeling to operations and maintenance activities, specifically moving operations, such as pavement testing, pavement marking, painting, snow removal, shoulder work,...
Application of the Hardman methodology to the Single Channel Ground-Airborne Radio System (SINCGARS)
NASA Technical Reports Server (NTRS)
1984-01-01
The HARDMAN methodology was applied to the various configurations of employment for an emerging Army multipurpose communications system. The methodology was used to analyze the manpower, personnel and training (MPT) requirements and associated costs, of the system concepts responsive to the Army's requirement for the Single Channel Ground-Airborne Radio System (SINCGARS). The scope of the application includes the analysis of two conceptual designs Cincinnati Electronics and ITT Aerospace/Optical Division for operating and maintenance support addressed through the general support maintenance echelon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lara-Curzio, Edgar; Rios, Orlando; Marquez-Rossy, Andres Emilio
ORNL collaborated with Faurecia Interior Systems to investigate the feasibility of developing a thermomagnetic preventive maintenance program for nickel tooling used in powder slush molding. It was found that thermal treatments at temperatures greater than 500°C can anneal strain hardening in nickel tooling and a range of temperatures and times for effective thermal annealing were identified. It was also observed that magnetic fields applied during thermal annealing do not alter the kinetics of strain hardening annealing. The results obtained in this investigation provide a foundation for establishing a preventive maintenance program for nickel tooling.
Conditioning of the vacuum system of the TPS storage ring without baking in situ
NASA Astrophysics Data System (ADS)
Chan, C. K.; Chang, C. C.; Shueh, C.; Yang, I. C.; Wu, L. H.; Chen, B. Y.; Cheng, C. M.; Huang, Y. T.; Chuang, J. Y.; Cheng, Y. T.; Hsiao, Y. M.; Sheng, Albert
2017-04-01
To shorten the machine downtime, a maintenance procedure without baking in situ has been developed and applied to maintain and to upgrade the vacuum system of the TPS storage ring. The data of photon-stimulated desorption (PSD) reveal no obvious discrepancy between baking and not baking the vacuum system in situ. A beam-conditioning dose of extent only 11.8 A h is required to recover quickly the dynamic pressure of an unbaked vacuum system to its pre-intervention value according to the TPS maintenance experience.
Reliability analysis of C-130 turboprop engine components using artificial neural network
NASA Astrophysics Data System (ADS)
Qattan, Nizar A.
In this study, we predict the failure rate of Lockheed C-130 Engine Turbine. More than thirty years of local operational field data were used for failure rate prediction and validation. The Weibull regression model and the Artificial Neural Network model including (feed-forward back-propagation, radial basis neural network, and multilayer perceptron neural network model); will be utilized to perform this study. For this purpose, the thesis will be divided into five major parts. First part deals with Weibull regression model to predict the turbine general failure rate, and the rate of failures that require overhaul maintenance. The second part will cover the Artificial Neural Network (ANN) model utilizing the feed-forward back-propagation algorithm as a learning rule. The MATLAB package will be used in order to build and design a code to simulate the given data, the inputs to the neural network are the independent variables, the output is the general failure rate of the turbine, and the failures which required overhaul maintenance. In the third part we predict the general failure rate of the turbine and the failures which require overhaul maintenance, using radial basis neural network model on MATLAB tool box. In the fourth part we compare the predictions of the feed-forward back-propagation model, with that of Weibull regression model, and radial basis neural network model. The results show that the failure rate predicted by the feed-forward back-propagation artificial neural network model is closer in agreement with radial basis neural network model compared with the actual field-data, than the failure rate predicted by the Weibull model. By the end of the study, we forecast the general failure rate of the Lockheed C-130 Engine Turbine, the failures which required overhaul maintenance and six categorical failures using multilayer perceptron neural network (MLP) model on DTREG commercial software. The results also give an insight into the reliability of the engine turbine under actual operating conditions, which can be used by aircraft operators for assessing system and component failures and customizing the maintenance programs recommended by the manufacturer.
The paper gives results of a study of civil engineering fabrics applied to fugitive dust problems. The fabrics, commonly used for ground stabilization, subsurface drainage, railroad construction and maintenance, sediment control, and erosion control, are available from Celanese, ...
DOT National Transportation Integrated Search
2012-01-01
Microsurfacing is a unique pavement preservation tool in the arsenal of maintenance agencies. It is known to : perform well when applied to the right pavement at the right time for the right distress. In order to ensure : microsurfacing performs well...
Data Citation & Acknowledgements
Atmospheric Science Data Center
2014-09-29
... under the NASA Applied Sciences Program within the Earth Science Division of the Science Mission Directorate. When POWER data products ... energy system design, system maintenance, project planning, policy making, etc.) or in a publication, we would appreciate receiving any ...
Applied Operations Research: Operator's Assistant
NASA Technical Reports Server (NTRS)
Cole, Stuart K.
2015-01-01
NASA operates high value critical equipment (HVCE) that requires trouble shooting, periodic maintenance and continued monitoring by Operations staff. The complexity HVCE and information required to maintain and trouble shoot HVCE to assure continued mission success as paper is voluminous. Training on new HVCE is commensurate with the need for equipment maintenance. LaRC Research Directorate has undertaken a proactive research to support Operations staff by initiation of the development and prototyping an electronic computer based portable maintenance aid (Operator's Assistant). This research established a goal with multiple objectives and a working prototype was developed. The research identified affordable solutions; constraints; demonstrated use of commercial off the shelf software; use of the US Coast Guard maintenance solution; NASA Procedure Representation Language; and the identification of computer system strategies; where these demonstrations and capabilities support the Operator, and maintenance. The results revealed validation against measures of effectiveness and overall proved a substantial training and capability sustainment tool. The research indicated that the OA could be deployed operationally at the LaRC Compressor Station with an expectation of satisfactorily results and to obtain additional lessons learned prior to deployment at other LaRC Research Directorate Facilities. The research revealed projected cost and time savings.
Switching Kalman filter for failure prognostic
NASA Astrophysics Data System (ADS)
Lim, Chi Keong Reuben; Mba, David
2015-02-01
The use of condition monitoring (CM) data to predict remaining useful life have been growing with increasing use of health and usage monitoring systems on aircraft. There are many data-driven methodologies available for the prediction and popular ones include artificial intelligence and statistical based approach. The drawback of such approaches is that they require a lot of failure data for training which can be scarce in practice. In lieu of this, methods using state-space and regression-based models that extract information from the data history itself have been explored. However, such methods have their own limitations as they utilize a single time-invariant model which does not represent changing degradation path well. This causes most degradation modeling studies to focus only on segments of their CM data that behaves close to the assumed model. In this paper, a state-space based method; the Switching Kalman Filter (SKF), is adopted for model estimation and life prediction. The SKF approach however, uses multiple models from which the most probable model is inferred from the CM data using Bayesian estimation before it is applied for prediction. At the same time, the inference of the degradation model itself can provide maintainers with more information for their planning. This SKF approach is demonstrated with a case study on gearbox bearings that were found defective from the Republic of Singapore Air Force AH64D helicopter. The use of in-service CM data allows the approach to be applied in a practical scenario and results showed that the developed SKF approach is a promising tool to support maintenance decision-making.
Webcam delivery of the Camperdown Program for adolescents who stutter: a phase I trial.
Carey, Brenda; O'Brian, Sue; Onslow, Mark; Packman, Ann; Menzies, Ross
2012-07-01
This Phase I clinical trial explored the viability of webcam Internet delivery of the Camperdown Program for adolescents who stutter. Method and Procedure Participants were 3 adolescents ages 13, 15, and 16 years, with moderate-severe stuttering. Each was treated with the Camperdown Program delivered by webcam with no clinic attendance. Primary outcome measures were percentage of syllables stuttered and number of treatment sessions to maintenance. Secondary outcome measures were speech naturalness, situation avoidance, self-reported stuttering severity, and parent and adolescent satisfaction. Data were collected pre treatment and at 1 day, 6 months, and 12 months post entry to maintenance. Participants entered maintenance after means of 18 sessions and 11 clinician hours. Group mean reduction of stuttering from pre treatment to entry to maintenance was 83%, from pre treatment to 6 months post entry to maintenance was 93%, and from pre treatment to 12 months post entry to maintenance was 74%. Self-reported stuttering severity ratings confirmed these results. Post entry to maintenance speech naturalness for participants fell within the range of that of 3 matched controls. However, avoidance of speech situations showed no corresponding improvements for 2 of the participants. The service delivery model was efficacious and efficient. All of the participants and their parents also found it appealing. Results justify a Phase II trial of the delivery model.
Product modular design incorporating preventive maintenance issues
NASA Astrophysics Data System (ADS)
Gao, Yicong; Feng, Yixiong; Tan, Jianrong
2016-03-01
Traditional modular design methods lead to product maintenance problems, because the module form of a system is created according to either the function requirements or the manufacturing considerations. For solving these problems, a new modular design method is proposed with the considerations of not only the traditional function related attributes, but also the maintenance related ones. First, modularity parameters and modularity scenarios for product modularity are defined. Then the reliability and economic assessment models of product modularity strategies are formulated with the introduction of the effective working age of modules. A mathematical model used to evaluate the difference among the modules of the product so that the optimal module of the product can be established. After that, a multi-objective optimization problem based on metrics for preventive maintenance interval different degrees and preventive maintenance economics is formulated for modular optimization. Multi-objective GA is utilized to rapidly approximate the Pareto set of optimal modularity strategy trade-offs between preventive maintenance cost and preventive maintenance interval difference degree. Finally, a coordinate CNC boring machine is adopted to depict the process of product modularity. In addition, two factorial design experiments based on the modularity parameters are constructed and analyzed. These experiments investigate the impacts of these parameters on the optimal modularity strategies and the structure of module. The research proposes a new modular design method, which may help to improve the maintainability of product in modular design.
NASA Astrophysics Data System (ADS)
Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.
2018-03-01
This paper draws on the "human reliability" concept as a structure for gaining insight into the maintenance workforce assessment in a process industry. Human reliability hinges on developing the reliability of humans to a threshold that guides the maintenance workforce to execute accurate decisions within the limits of resources and time allocations. This concept offers a worthwhile point of deviation to encompass three elegant adjustments to literature model in terms of maintenance time, workforce performance and return-on-workforce investments. These fully explain the results of our influence. The presented structure breaks new grounds in maintenance workforce theory and practice from a number of perspectives. First, we have successfully implemented fuzzy goal programming (FGP) and differential evolution (DE) techniques for the solution of optimisation problem in maintenance of a process plant for the first time. The results obtained in this work showed better quality of solution from the DE algorithm compared with those of genetic algorithm and particle swarm optimisation algorithm, thus expressing superiority of the proposed procedure over them. Second, the analytical discourse, which was framed on stochastic theory, focusing on specific application to a process plant in Nigeria is a novelty. The work provides more insights into maintenance workforce planning during overhaul rework and overtime maintenance activities in manufacturing systems and demonstrated capacity in generating substantially helpful information for practice.
Development of maintenance composite priority index for buildings in Palestine: A pilot case study
NASA Astrophysics Data System (ADS)
Issa, Amjad; Awad, Riyad
2017-11-01
The current building maintenance practices in Palestine are not based on scientific systematic methods. Most of the municipalities use one criterion to define the maintenance priorities, which is the "worst-first" criterion. Therefore, the current practices in defining buildings maintenance plans are not dealing with the known phases that are generally followed, including those in establishing building inventories, building condition survey, detailed visual inspection, identification of the proper maintenance and rehabilitation measures, and setting priorities. Accordingly, the recent preparation of the Operation and Maintenance (O&M) Manual for Palestinian municipalities is an important step to guide them towards preparing and implementing their O&M priority-based plans, considering scare resources. During the course of preparation of the Manual, the proposed procedures were applied at ten pilot municipalities. This study aims to explore the outcome of the implementation of the 2014/2015 O&M buildings maintenance priorities at these municipalities through the development of maintenance composite priority index (PI). The new proposed priority index is a scientific tool that will identify the priority of maintenance buildings through using a systematic procedure instead of first worst one. To achieve this, analyses of the outcome of a questionnaire designed to collect relevant information from these municipalities was conducted. The maintenance priority index for buildings is calculated considering different indicators among them building status (condition), classification and importance of the building, number of beneficiaries (users), safety aspects (severity level in the building), and people complaints. The main component of the PI is the building condition index (BCI) which forms about 40% of the total weight. The physical inspection, which is the main input for calculating the BCI, is conducted on two levels; the primary level, and the secondary level. The buildings are ranked in descending order based on the PI values for each public building. The buildings that have the highest values of PI take the most priority till the specified asset maintenance budget for the targeted year is achieved. Finally, the results indicate that most of the maintenance works are funded by municipalities own budgets and not by the government.
Khangaonkar, Tarang; Nugraha, Adi; Hinton, Steve; ...
2017-04-21
The 11 mile (1.6 km) Swinomish Federal Navigation Channel provides a safe and short passage to fishing and recreational craft in and out of Northern Puget Sound by connecting Skagit and Padilla Bays, US State abbrev., USA. A network of dikes and jetties were constructed through the Swinomish corridor between 1893 and 1936 to improve navigation functionality. Over the years, these river training dikes and jetties designed to minimize sedimentation in the channel have deteriorated, resulting in reduced protection of the channel. The need to repair or modify dikes/jetties for channel maintenance, however, may conflict with salmon habitat restoration goalsmore » aimed at improving access, connectivity and brackish water habitat. Several restoration projects have been proposed in the Skagit delta involving breaching, lowering, or removal of dikes. To assess relative merits of the available alternatives, a hydrodynamic model of the Skagit River estuary was developed using the Finite Volume Community Ocean Model (FVCOM). Here, in this paper, we present the refinement and calibration of the model using oceanographic data collected from the years 2006 and 2009 with a focus on the sediment and brackish water transport from the river and Skagit Bay tide flats to the Swinomish Channel. The model was applied to assess the feasibility of achieving the desired dual outcome of (a) reducing sedimentation and shoaling in the Swinomish Channel and (b) providing a direct migration pathway and improved conveyance of freshwater into the Swinomish Channel. Finally, the potential reduction in shoaling through site-specific structure repairs is evaluated. Similarly, the potential to significantly improve of brackish water habitat through dike breach restoration actions using the McGlinn Causeway project example, along with its impacts on sediment deposition in the Swinomish Navigation Channel, is examined« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khangaonkar, Tarang; Nugraha, Adi; Hinton, Steve
The 11 mile (1.6 km) Swinomish Federal Navigation Channel provides a safe and short passage to fishing and recreational craft in and out of Northern Puget Sound by connecting Skagit and Padilla Bays, US State abbrev., USA. A network of dikes and jetties were constructed through the Swinomish corridor between 1893 and 1936 to improve navigation functionality. Over the years, these river training dikes and jetties designed to minimize sedimentation in the channel have deteriorated, resulting in reduced protection of the channel. The need to repair or modify dikes/jetties for channel maintenance, however, may conflict with salmon habitat restoration goalsmore » aimed at improving access, connectivity and brackish water habitat. Several restoration projects have been proposed in the Skagit delta involving breaching, lowering, or removal of dikes. To assess relative merits of the available alternatives, a hydrodynamic model of the Skagit River estuary was developed using the Finite Volume Community Ocean Model (FVCOM). Here, in this paper, we present the refinement and calibration of the model using oceanographic data collected from the years 2006 and 2009 with a focus on the sediment and brackish water transport from the river and Skagit Bay tide flats to the Swinomish Channel. The model was applied to assess the feasibility of achieving the desired dual outcome of (a) reducing sedimentation and shoaling in the Swinomish Channel and (b) providing a direct migration pathway and improved conveyance of freshwater into the Swinomish Channel. Finally, the potential reduction in shoaling through site-specific structure repairs is evaluated. Similarly, the potential to significantly improve of brackish water habitat through dike breach restoration actions using the McGlinn Causeway project example, along with its impacts on sediment deposition in the Swinomish Navigation Channel, is examined« less
Instruction manual model 600F, data transmission test set
NASA Technical Reports Server (NTRS)
1972-01-01
Information necessary for the operation and maintenance of the Model 600F Data Transmission Test Set is presented. A description is contained of the physical and functional characteristics; pertinent installation data; instructions for operating the equipment; general and detailed principles of operation; preventive and corrective maintenance procedures; and block, logic, and component layout diagrams of the equipment and its major component assemblies.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-05
... to these aircraft if Bombardier Service Bulletin (SB) 601-0590 [Scheduled Maintenance Instructions... information: Challenger 601 Time Limits/Maintenance Checks, PSP 601-5, Revision 38, dated June 19, 2009. Challenger 601 Time Limits/Maintenance Checks, PSP 601A-5, Revision 34, dated June 19, 2009. Challenger 604...
2014-10-01
Remodeling Factor in Sonic Hedgehog -Dependent Medulloblastoma Initiation and Maintenance PRINCIPAL INVESTIGATOR: Xuanming Shi CONTRACTING...Function of Brg1 Chromatin Remodeling Factor in Sonic Hedgehog -Dependent 5b. GRANT NUMBER W81XWH-12-1-0527 Medulloblastoma Initiation and Maintenance...medulloblastoma. 15. SUBJECT TERMS Medulloblastoma, Sonic Hedgehog , Chromatin remodeling, BAF complex, Brg1, mouse model of shh-subtype medulloblastoma
Self-Esteem Maintenance in Family Dynamics.
ERIC Educational Resources Information Center
Tesser, Abraham
1980-01-01
In this study, a self-esteem maintenance model is introduced and is used to test predictions about sibling identification, sibling friction, and the closeness of father-son relationships as they relate to sibling performance. (Author/SS)
Put the lid on VOC emissions from maintenance coatings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morgan, R.E.
1996-11-01
After the coating film is applied to the substrate, the solvents evaporate and generally become an environmental liability. Solvents used by the coatings industry have been a major environmental issue for many years. Over the years, regulations have been aimed at reducing or eliminating photochemically reactive solvents--those that react in the atmosphere with nitrogen oxides in the atmosphere with nitrogen oxides in the presence of sunlight and heat to form ozones. Many of the solvents used in the coatings industry are, in fact, photochemically reactive. The rules regulating the maintenance coatings industry can generally be divided into three categories: 1.more » Rules aimed at restricting the VOCs in steel fabricating shops and paint shops. 2. Rules aimed at regulating the emission of VOCs from coatings applied in the field such as on bridges or industrial structures. 3. Rules aimed at the shipbuilding industry where coatings are applied to marine vessels. The paper discusses reducing VOCs, penetrating sealers, mastics, tank linings, inorganic zincs, topcoats--waterborne acrylics, zero-VOC urethane/water systems, and solventless topcoats.« less
Prediction of surface distress using neural networks
NASA Astrophysics Data System (ADS)
Hamdi, Hadiwardoyo, Sigit P.; Correia, A. Gomes; Pereira, Paulo; Cortez, Paulo
2017-06-01
Road infrastructures contribute to a healthy economy throughout a sustainable distribution of goods and services. A road network requires appropriately programmed maintenance treatments in order to keep roads assets in good condition, providing maximum safety for road users under a cost-effective approach. Surface Distress is the key element to identify road condition and may be generated by many different factors. In this paper, a new approach is aimed to predict Surface Distress Index (SDI) values following a data-driven approach. Later this model will be accordingly applied by using data obtained from the Integrated Road Management System (IRMS) database. Artificial Neural Networks (ANNs) are used to predict SDI index using input variables related to the surface of distress, i.e., crack area and width, pothole, rutting, patching and depression. The achieved results show that ANN is able to predict SDI with high correlation factor (R2 = 0.996%). Moreover, a sensitivity analysis was applied to the ANN model, revealing the influence of the most relevant input parameters for SDI prediction, namely rutting (59.8%), crack width (29.9%) and crack area (5.0%), patching (3.0%), pothole (1.7%) and depression (0.3%).
Multi-mode clustering model for hierarchical wireless sensor networks
NASA Astrophysics Data System (ADS)
Hu, Xiangdong; Li, Yongfu; Xu, Huifen
2017-03-01
The topology management, i.e., clusters maintenance, of wireless sensor networks (WSNs) is still a challenge due to its numerous nodes, diverse application scenarios and limited resources as well as complex dynamics. To address this issue, a multi-mode clustering model (M2 CM) is proposed to maintain the clusters for hierarchical WSNs in this study. In particular, unlike the traditional time-trigger model based on the whole-network and periodic style, the M2 CM is proposed based on the local and event-trigger operations. In addition, an adaptive local maintenance algorithm is designed for the broken clusters in the WSNs using the spatial-temporal demand changes accordingly. Numerical experiments are performed using the NS2 network simulation platform. Results validate the effectiveness of the proposed model with respect to the network maintenance costs, node energy consumption and transmitted data as well as the network lifetime.
Degradation modeling of mid-power white-light LEDs by using Wiener process.
Huang, Jianlin; Golubović, Dušan S; Koh, Sau; Yang, Daoguo; Li, Xiupeng; Fan, Xuejun; Zhang, G Q
2015-07-27
The IES standard TM-21-11 provides a guideline for lifetime prediction of LED devices. As it uses average normalized lumen maintenance data and performs non-linear regression for lifetime modeling, it cannot capture dynamic and random variation of the degradation process of LED devices. In addition, this method cannot capture the failure distribution, although it is much more relevant in reliability analysis. Furthermore, the TM-21-11 only considers lumen maintenance for lifetime prediction. Color shift, as another important performance characteristic of LED devices, may also render significant degradation during service life, even though the lumen maintenance has not reached the critical threshold. In this study, a modified Wiener process has been employed for the modeling of the degradation of LED devices. By using this method, dynamic and random variations, as well as the non-linear degradation behavior of LED devices, can be easily accounted for. With a mild assumption, the parameter estimation accuracy has been improved by including more information into the likelihood function while neglecting the dependency between the random variables. As a consequence, the mean time to failure (MTTF) has been obtained and shows comparable result with IES TM-21-11 predictions, indicating the feasibility of the proposed method. Finally, the cumulative failure distribution was presented corresponding to different combinations of lumen maintenance and color shift. The results demonstrate that a joint failure distribution of LED devices could be modeled by simply considering their lumen maintenance and color shift as two independent variables.
Confirmatory factor analysis for two questionnaires of caregiving in eating disorders
Hibbs, Rebecca; Rhind, Charlotte; Sallis, Hannah; Goddard, Elizabeth; Raenker, Simone; Ayton, Agnes; Bamford, Bryony; Arcelus, Jon; Boughton, Nicky; Connan, Frances; Goss, Ken; Lazlo, Bert; Morgan, John; Moore, Kim; Robertson, David; Schreiber-Kounine, Christa; Sharma, Sonu; Whitehead, Linette; Lacey, Hubert; Schmidt, Ulrike; Treasure, Janet
2014-01-01
Objective: Caring for someone diagnosed with an eating disorder (ED) is associated with a high level of burden and psychological distress which can inadvertently contribute to the maintenance of the illness. The Eating Disorders Symptom Impact Scale (EDSIS) and Accommodation and Enabling Scale for Eating Disorders (AESED) are self-report scales to assess elements of caregiving theorised to contribute to the maintenance of an ED. Further validation and confirmation of the factor structures for these scales are necessary for rigorous evaluation of complex interventions which target these modifiable elements of caregiving. Method: EDSIS and AESED data from 268 carers of people with anorexia nervosa (AN), recruited from consecutive admissions to 15 UK inpatient or day patient hospital units, were subjected to confirmatory factor analysis to test model fit by applying the existing factor structures: (a) four-factor structure for the EDSIS and (b) five-factor structure for the AESED. Results: Confirmatory factor analytic results support the existing four-factor and five-factor structures for the EDSIS and the AESED, respectively. Discussion: The present findings provide further validation of the EDSIS and the AESED as tools to assess modifiable elements of caregiving for someone with an ED. PMID:25750785
Sensor Measurement Strategies for Monitoring Offshore Wind and Wave Energy Devices
NASA Astrophysics Data System (ADS)
O'Donnell, Deirdre; Srbinovsky, Bruno; Murphy, Jimmy; Popovici, Emanuel; Pakrashi, Vikram
2015-07-01
While the potential of offshore wind and wave energy devices is well established and accepted, operations and maintenance issues are still not very well researched or understood. In this regard, scaled model testing has gained popularity over time for such devices at various technological readiness levels. The dynamic response of these devices are typically measured by different instruments during such scaled tests but agreed sensor choice, measurement and placement guidelines are still not in place. This paper compared the dynamic responses of some of these sensors from a scaled ocean wave testing to highlight the importance of sensor measurement strategies. The possibility of using multiple, cheaper sensors of seemingly inferior performance as opposed to the deployment of a small number of expensive and accurate sensors are also explored. An energy aware adaptive sampling theory is applied to highlight the possibility of more efficient computing when large volumes of data are available from the tested structures. Efficient sensor measurement strategies are expected to have a positive impact on the development of an device at different technological readiness levels while it is expected to be helpful in reducing operation and maintenance costs if such an approach is considered for the devices when they are in operation.
Application of multiphase modelling for vortex occurrence in vertical pump intake - a review
NASA Astrophysics Data System (ADS)
Samsudin, M. L.; Munisamy, K. M.; Thangaraju, S. K.
2015-09-01
Vortex formation within pump intake is one of common problems faced for power plant cooling water system. This phenomenon, categorised as surface and sub-surface vortices, can lead to several operational problems and increased maintenance costs. Physical model study was recommended from published guidelines but proved to be time and resource consuming. Hence, the use of Computational Fluid Dynamics (CFD) is an attractive alternative in managing the problem. At the early stage, flow analysis was conducted using single phase simulation and found to find good agreement with the observation from physical model study. With the development of computers, multiphase simulation found further enhancement in obtaining accurate results for representing air entrainment and sub-surface vortices which were earlier not well predicted from the single phase simulation. The purpose of this paper is to describe the application of multiphase modelling with CFD analysis for investigating vortex formation for a vertically inverted pump intake. In applying multiphase modelling, there ought to be a balance between the acceptable usage for computational time and resources and the degree of accuracy and realism in the results as expected from the analysis.
Evaluation of deicer applications on open graded pavements : final report.
DOT National Transportation Integrated Search
2006-04-01
The Oregon Department of Transportation (ODOT) winter maintenance practices include plowing, sanding, and applying winter anti-icing/deicing liquids. These activities are performed on dense-graded as well as open-graded pavements. During the winters ...
32 CFR 644.372 - Care and custody through interim use.
Code of Federal Regulations, 2011 CFR
2011-07-01
... maintenance and restoration as required by standard Corps of Engineers lease forms. Where a portion of an... the portion leased. The Economy Act may not apply in some cases where industrial plants are determined...
32 CFR 644.372 - Care and custody through interim use.
Code of Federal Regulations, 2010 CFR
2010-07-01
... maintenance and restoration as required by standard Corps of Engineers lease forms. Where a portion of an... the portion leased. The Economy Act may not apply in some cases where industrial plants are determined...
Improving the accuracy and usability of Iowa falling weight deflectometer data : [summary].
DOT National Transportation Integrated Search
2013-05-01
Highway agencies periodically evaluate the structural condition of roads as part of their routine maintenance and rehabilitation activities. The falling-weight deflectometer (FWD) test measures road surface deflections resulting from an applied impul...
Sustainable construction in remote cold regions.
DOT National Transportation Integrated Search
2015-12-01
The goal of this project was to identify sustainable construction techniques appropriate for remote and cold regions, some of which apply to : operations and maintenance as well. The vast body of literature regarding green construction in warm region...
21 CFR 111.15 - What sanitation requirements apply to your physical plant and grounds?
Code of Federal Regulations, 2011 CFR
2011-04-01
... maintenance include: (1) Properly storing equipment, removing litter and waste, and cutting weeds or grass... must dispose of sewage into an adequate sewage system or through other adequate means. (h) Bathrooms...
NASA Astrophysics Data System (ADS)
Rakhmawati, Lusia; Irwansyah Febriyanto, Fariz
2018-04-01
This study aimed to investigate satisfaction levels, among of the eleventh-grade students majoring in audio-video technique, towards the instructional media CCTV trainer kit: The CCTV Prototype and job sheet on to and analyzed perspectives of the practical approach to learning using CCTV prototype to improve installation skills in the electronic appliance repair and maintenance class. Survey questionnaires and instructional media were applied to data collection. The students’ satisfaction towards the instructional media in teaching and learning process was presented in positive responses, 91.94 % satisfied. The finding reveals that the instructional media using trainer could better to overcome the need a practical approach to learning. Furthermore, using trainer kit media creates an environment where students can support each other and receive feedback from their peers. They performed practice activities that help them apply the new information from the steps on the job sheet.
Scheerman, Janneke F M; van Empelen, Pepijn; van Loveren, Cor; Pakpour, Amir H; van Meijel, Berno; Gholami, Maryam; Mierzaie, Zaher; van den Braak, Matheus C T; Verrips, Gijsbert H W
2017-11-01
The Health Action Process Approach (HAPA) model addresses health behaviours, but it has never been applied to model adolescents' oral hygiene behaviour during fixed orthodontic treatment. This study aimed to apply the HAPA model to explain adolescents' oral hygiene behaviour and dental plaque during orthodontic treatment with fixed appliances. In this cross-sectional study, 116 adolescents with fixed appliances from an orthodontic clinic situated in Almere (the Netherlands) completed a questionnaire assessing oral health behaviours and the psychosocial factors of the HAPA model. Linear regression analyses were performed to examine the factors associated with dental plaque, toothbrushing, and the use of a proxy brush. Stepwise regression analysis showed that lower amounts of plaque were significantly associated with higher frequency of the use of a proxy brush (R 2 = 45%), higher intention of the use of a proxy brush (R 2 = 5%), female gender (R 2 = 2%), and older age (R 2 = 2%). The multiple regression analyses revealed that higher action self-efficacy, intention, maintenance self-efficacy, and a higher education were significantly associated with the use of a proxy brush (R 2 = 45%). Decreased levels of dental plaque are mainly associated with increased use of a proxy brush that is subsequently associated with a higher intention and self-efficacy to use the proxy brush. © 2017 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Artificial Intelligent Platform as Decision Tool for Asset Management, Operations and Maintenance.
2018-01-04
An Artificial Intelligence (AI) system has been developed and implemented for water, wastewater and reuse plants to improve management of sensors, short and long term maintenance plans, asset and investment management plans. It is based on an integrated approach to capture data from different computer systems and files. It adds a layer of intelligence to the data. It serves as a repository of key current and future operations and maintenance conditions that a plant needs have knowledge of. With this information, it is able to simulate the configuration of processes and assets for those conditions to improve or optimize operations, maintenance and asset management, using the IViewOps (Intelligent View of Operations) model. Based on the optimization through model runs, it is able to create output files that can feed data to other systems and inform the staff regarding optimal solutions to the conditions experienced or anticipated in the future.
Dissecting Embryonic Stem Cell Self-Renewal and Differentiation Commitment from Quantitative Models.
Hu, Rong; Dai, Xianhua; Dai, Zhiming; Xiang, Qian; Cai, Yanning
2016-10-01
To model quantitatively embryonic stem cell (ESC) self-renewal and differentiation by computational approaches, we developed a unified mathematical model for gene expression involved in cell fate choices. Our quantitative model comprised ESC master regulators and lineage-specific pivotal genes. It took the factors of multiple pathways as input and computed expression as a function of intrinsic transcription factors, extrinsic cues, epigenetic modifications, and antagonism between ESC master regulators and lineage-specific pivotal genes. In the model, the differential equations of expression of genes involved in cell fate choices from regulation relationship were established according to the transcription and degradation rates. We applied this model to the Murine ESC self-renewal and differentiation commitment and found that it modeled the expression patterns with good accuracy. Our model analysis revealed that Murine ESC was an attractor state in culture and differentiation was predominantly caused by antagonism between ESC master regulators and lineage-specific pivotal genes. Moreover, antagonism among lineages played a critical role in lineage reprogramming. Our results also uncovered that the ordered expression alteration of ESC master regulators over time had a central role in ESC differentiation fates. Our computational framework was generally applicable to most cell-type maintenance and lineage reprogramming.
Maintenance Policy in Public-Transport Involving Government Subsidy
NASA Astrophysics Data System (ADS)
Pasaribu, U. S.; Bayuzetra, Y.; Gunawan, L. E.; Husniah, H.
2018-02-01
A public transport with government subsidy is considered to encourage the sustainability of the transportation. The transportations revenue is determined by the maximum of the uptimes of the vehicle. In this paper, we study a one-dimensional maintenance policy for new vehicle which is characterized by age parameter. We consider that the degradation of the vehicle is affected by the age of the vehicle, and modelled by using a one-dimensional approach. The owner performs both preventive and corrective maintenance actions, and the preventive maintenance action will reduce the vehicle failure rate and hence it will decrease the corrective maintenance cost during the life time of the vehicle. The decision problem for the owner is to find the optimal preventive maintenance time of the vehicle of each subsidy option offered by maximizing the expected profit for each subsidy.
The role of data fusion in predictive maintenance using digital twin
NASA Astrophysics Data System (ADS)
Liu, Zheng; Meyendorf, Norbert; Mrad, Nezih
2018-04-01
Modern aerospace industry is migrating from reactive to proactive and predictive maintenance to increase platform operational availability and efficiency, extend its useful life cycle and reduce its life cycle cost. Multiphysics modeling together with data-driven analytics generate a new paradigm called "Digital Twin." The digital twin is actually a living model of the physical asset or system, which continually adapts to operational changes based on the collected online data and information, and can forecast the future of the corresponding physical counterpart. This paper reviews the overall framework to develop a digital twin coupled with the industrial Internet of Things technology to advance aerospace platforms autonomy. Data fusion techniques particularly play a significant role in the digital twin framework. The flow of information from raw data to high-level decision making is propelled by sensor-to-sensor, sensor-to-model, and model-to-model fusion. This paper further discusses and identifies the role of data fusion in the digital twin framework for aircraft predictive maintenance.
Modeling-Enabled Systems Nutritional Immunology
Verma, Meghna; Hontecillas, Raquel; Abedi, Vida; Leber, Andrew; Tubau-Juni, Nuria; Philipson, Casandra; Carbo, Adria; Bassaganya-Riera, Josep
2016-01-01
This review highlights the fundamental role of nutrition in the maintenance of health, the immune response, and disease prevention. Emerging global mechanistic insights in the field of nutritional immunology cannot be gained through reductionist methods alone or by analyzing a single nutrient at a time. We propose to investigate nutritional immunology as a massively interacting system of interconnected multistage and multiscale networks that encompass hidden mechanisms by which nutrition, microbiome, metabolism, genetic predisposition, and the immune system interact to delineate health and disease. The review sets an unconventional path to apply complex science methodologies to nutritional immunology research, discovery, and development through “use cases” centered around the impact of nutrition on the gut microbiome and immune responses. Our systems nutritional immunology analyses, which include modeling and informatics methodologies in combination with pre-clinical and clinical studies, have the potential to discover emerging systems-wide properties at the interface of the immune system, nutrition, microbiome, and metabolism. PMID:26909350
NASA Astrophysics Data System (ADS)
Aye, S. A.; Heyns, P. S.
2017-02-01
This paper proposes an optimal Gaussian process regression (GPR) for the prediction of remaining useful life (RUL) of slow speed bearings based on a novel degradation assessment index obtained from acoustic emission signal. The optimal GPR is obtained from an integration or combination of existing simple mean and covariance functions in order to capture the observed trend of the bearing degradation as well the irregularities in the data. The resulting integrated GPR model provides an excellent fit to the data and improves over the simple GPR models that are based on simple mean and covariance functions. In addition, it achieves a low percentage error prediction of the remaining useful life of slow speed bearings. These findings are robust under varying operating conditions such as loading and speed and can be applied to nonlinear and nonstationary machine response signals useful for effective preventive machine maintenance purposes.
Feasibility study of self-powered magnetorheological damper systems
NASA Astrophysics Data System (ADS)
Chen, Chao; Liao, Wei-Hsin
2012-04-01
This paper is aimed to provide a feasibility study of self-powered magnetorheological (MR) damper systems, which could convert vibration and shock energy into electrical energy to power itself under control. The self-powered feature could bring merits such as higher reliability, energy saving, and less maintenance for the MR damper systems. A self-powered MR damper system is proposed and modeled. The criterion whether the MR damper system is self-powered or not is proposed. A prototype of MR damper with power generation is designed, fabricated, and tested. The modeling of this damper is experimentally validated. Then the damper is applied to a 2 DOF suspension system under on-off skyhook controller, to obtain the self-powered working range and vibration control performance. Effects of key factors on the self-powered MR damper systems are studied. Design considerations are given in order to increase the self-powered working range.
NASA Astrophysics Data System (ADS)
Cardinale, T.; Valva, R.; Lucarelli, M.
2013-02-01
The Summer School of Surveying and 3D modelling in Paestum was an opportunity to explore the use of innovative tools and advanced techniques in the design, implementation and management of surveys of historic and artistic complexes. In general such methods are used specifically for the development and management of vulnerability maps of existing heritage and so for the preventive conservation and valorisation of the built environment. The accurate detection of risk situations and the systematic promotion of highly selected and minimally invasive maintenance practices means that restoration and the efficiency of cycles of intervention can be optimized, with clear benefits from economic and cultural points of view. The group worked on the survey and 3D modelling of the Temple of Neptune, the Sphinx and the Metope of the Archaeological Park in Paestum.
ERIC Educational Resources Information Center
Boerner, Kathrin; Jopp, Daniela
2007-01-01
This article focuses on the common and unique contributions of three major life-span theories in addressing improvement/maintenance and reorientation, which represent central processes of coping with major life change and loss. For this purpose, we review and compare the dual-process model of assimilative and accommodative coping, the model of…
The purpose of this SOP is to detail the operation and maintenance of an Instruments, SA Inc., Jobin-Yvon Model 70 (JY-70) inductively coupled plasma atomic emissions spectrometry (ICP-AES). This procedure was followed to ensure consistent data retrieval during the Arizona NHEXA...
From BIM to GIS at the Smithsonian Institution
NASA Astrophysics Data System (ADS)
Günther-Diringer, Detlef
2018-05-01
BIM-files (Building Information Models) are in modern architecture and building management a basic prerequisite for successful creation of construction engineering projects. At the facilities department of the Smithsonian Institution more than six hundred buildings were maintained. All facilities were digital available in an ESRI ArcGIS-environment with connection to the database information about single rooms with the usage and further maintenance information. These data are organization wide available by an intranet viewer, but only in a two-dimensional representation. Goal of the carried out project was the development of a workflow from available BIM-models to the given GIS-structure. The test-environment were the BIM-models of the buildings of the Smithsonian museums along the Washington Mall. Based on new software editions of Autodesk Revit, FME and ArcGIS Pro the workflow from BIM to the GIS-data structure of the Smithsonian was successfully developed and may be applied for the setup of the future 3D intranet viewer.
NASA Astrophysics Data System (ADS)
Pattabhiraman, Sriram
Airplane fuselage structures are designed with the concept of damage tolerance, wherein small damage are allowed to remain on the airplane, and damage that otherwise affect the safety of the structure are repaired. The damage critical to the safety of the fuselage are repaired by scheduling maintenance at pre-determined intervals. Scheduling maintenance is an interesting trade-off between damage tolerance and cost. Tolerance of larger damage would require less frequent maintenance and hence, a lower cost, to maintain a certain level of reliability. Alternatively, condition-based maintenance techniques have been developed using on-board sensors, which track damage continuously and request maintenance only when the damage size crosses a particular threshold. This effects a tolerance of larger damage than scheduled maintenance, leading to savings in cost. This work quantifies the savings of condition-based maintenance over scheduled maintenance. The work also quantifies converting the cost savings into weight savings. Structural health monitoring will need time to be able to establish itself as a stand-alone system for maintenance, due to concerns on its diagnosis accuracy and reliability. This work also investigates the effect of synchronizing structural health monitoring system with scheduled maintenance. This work uses on-board SHM equipment skip structural airframe maintenance (a subsect of scheduled maintenance), whenever deemed unnecessary while maintain a desired level of safety of structure. The work will also predict the necessary maintenance for a fleet of airplanes, based on the current damage status of the airplanes. The work also analyses the possibility of false alarm, wherein maintenance is being requested with no critical damage on the airplane. The work use SHM as a tool to identify lemons in a fleet of airplanes. Lemons are those airplanes that would warrant more maintenance trips than the average behavior of the fleet.
NASA Astrophysics Data System (ADS)
Todeschini, Ilaria; Di Napoli, Claudia; Pretto, Ilaria; Merler, Giacomo; Cavaliere, Roberto; Apolloni, Roberto; Antonacci, Gianluca; Piazza, Andrea; Benedetti, Guido
2016-08-01
During the winter period ice is likely to form on roads, making pavement surfaces slippery and increasing accident risk. Road surface temperature (RST) is one of the most important parameters in ice formation. The LIFE+ "CLEANROADS" project aims to forecast RSTs in advance in order to support road maintenance services in the timely and effective preparation of preventive anti-icing measures. This support is provided through a novel MDSS (Maintenance Decision Support System). The final goal of the project is to quantitatively demonstrate that the implemented MDSS is capable to minimize the consumption of chemical anti-icing reagents (e.g. sodium chloride) and the associated environmental (water and air) impact while maintaining the current high levels of road safety. In the CLEAN-ROADS system RSTs have been forecast by applying the numerical model METRo (Model of the Environment and Temperature of Roads) to a network of RWIS (Road Weather Information System) stations installed on a test route in the Adige Valley (Italy). This forecast is however local and does not take into account typical peculiarities along road network, such as the presence of road sections that are particularly prone to ice formation. Thermal mapping, i.e. the acquisition of mobile RST measurements through infrared thermometry, permits to (i) identify and map those sections, and (ii) extend the forecast from a RWIS station to adjacent areas. The processing of thermal mapping signals is however challenging because of random variations in the road surface emissivity. To overcome this we have acquired several thermal mapping traces along the test route during winter seasons 2014-2015 and 2015-2016. We have then defined a "characteristic" thermal fingerprint as a function of all its historical thermal mapping signals, and used it to spatialize local METRo forecasts. Preliminary results suggest the high potential of such a technique for winter road applications.
Dynamic shared state maintenance in distributed virtual environments
NASA Astrophysics Data System (ADS)
Hamza-Lup, Felix George
Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. Particularly challenging are distributed interactive Virtual Environments (VE) that allow knowledge sharing through 3D information. The purpose of this work is to address the problem of latency in distributed interactive VE and to develop a conceptual model for consistency maintenance in these environments based on the participant interaction model. An area that needs to be explored is the relationship between the dynamic shared state and the interaction with the virtual entities present in the shared scene. Mixed Reality (MR) and VR environments must bring the human participant interaction into the loop through a wide range of electronic motion sensors, and haptic devices. Part of the work presented here defines a novel criterion for categorization of distributed interactive VE and introduces, as well as analyzes, an adaptive synchronization algorithm for consistency maintenance in such environments. As part of the work, a distributed interactive Augmented Reality (AR) testbed and the algorithm implementation details are presented. Currently the testbed is part of several research efforts at the Optical Diagnostics and Applications Laboratory including 3D visualization applications using custom built head-mounted displays (HMDs) with optical motion tracking and a medical training prototype for endotracheal intubation and medical prognostics. An objective method using quaternion calculus is applied for the algorithm assessment. In spite of significant network latency, results show that the dynamic shared state can be maintained consistent at multiple remotely located sites. In further consideration of the latency problems and in the light of the current trends in interactive distributed VE applications, we propose a hybrid distributed system architecture for sensor-based distributed VE that has the potential to improve the system real-time behavior and scalability. (Abstract shortened by UMI.)
Application of 6D Building Information Model (6D BIM) for Business-storage Building in Slovenia
NASA Astrophysics Data System (ADS)
Pučko, Zoran; Vincek, Dražen; Štrukelj, Andrej; Šuman, Nataša
2017-10-01
The aim of this paper is to present an application of 6D building information modelling (6D BIM) on a real business-storage building in Slovenia. First, features of building maintenance in general are described according to the current Slovenian legislation, and also a general principle of BIM is given. After that, step-by-step activities for modelling 6D BIM are exposed, namely from Element list for maintenance, determination of their lifetime and service measures, cost analysing and time analysing to 6D BIM modelling. The presented 6D BIM model is designed in a unique way in which cost analysis is performed as 5D BIM model with linked data to use BIM Construction Project Management Software (Vico Office), integrated with 3D BIM model, whereas time analysis as 4D BIM model is carried out as non-linked data with the help of Excel (without connection to 3D BIM model). The paper is intended to serve as a guide to the building owners to prepare 6D BIM and to provide an insight into the relevant dynamic information about intervals and costs for execution of maintenance works in the whole building lifecycle.
Uringa, Evert-Jan; Youds, Jillian L; Lisaingo, Kathleen; Lansdorp, Peter M; Boulton, Simon J
2011-03-01
Telomere maintenance and DNA repair are crucial processes that protect the genome against instability. RTEL1, an essential iron-sulfur cluster-containing helicase, is a dominant factor that controls telomere length in mice and is required for telomere integrity. In addition, RTEL1 promotes synthesis-dependent strand annealing to direct DNA double-strand breaks into non-crossover outcomes during mitotic repair and in meiosis. Here, we review the role of RTEL1 in telomere maintenance and homologous recombination and discuss models linking RTEL1's enzymatic activity to its function in telomere maintenance and DNA repair.
Fleet equipment performance measurement preventive maintenance model : final report.
DOT National Transportation Integrated Search
2014-04-01
The concept of preventive maintenance is very important in the effective management and deployment of : vehicle fleets. The Texas Department of Transportation (TxDOT) operates a large fleet of on-road and offroad : equipment. Newer engines and vehicl...
ERIC Educational Resources Information Center
Gable, Robert A.; And Others
1992-01-01
An instructional process for facilitating maintenance and generalization of academic skills is presented, using the ABCD'S (Antecedent Events, Behavior, Consequent Events, Data, and Setting Events) Generalization Intervention Model. (JDD)
Maintenance and operations cost model for DSN subsystems
NASA Technical Reports Server (NTRS)
Burt, R. W.; Lesh, J. R.
1977-01-01
A procedure is described which partitions the recurring costs of the Deep Space Network (DSN) over the individual DSN subsystems. The procedure results in a table showing the maintenance, operations, sustaining engineering and supportive costs for each subsystems.
Applying Independent Verification and Validation to Automatic Test Equipment
NASA Technical Reports Server (NTRS)
Calhoun, Cynthia C.
1997-01-01
This paper describes a general overview of applying Independent Verification and Validation (IV&V) to Automatic Test Equipment (ATE). The overview is not inclusive of all IV&V activities that can occur or of all development and maintenance items that can be validated and verified, during the IV&V process. A sampling of possible IV&V activities that can occur within each phase of the ATE life cycle are described.
BOOSTER CHLORINATION FOR MANAGING DISINFECTANT RESIDUALS
Booster chlorination is an approach to residual maintenance in which chlorine is applied at strategic locations within the distribution system. Situations in which booster chlorination may be most effective for maintaining a residual are explained informally in the context of a ...
NASA Astrophysics Data System (ADS)
Zhao, Shouwei; Zhang, Yong; Zhou, Bin; Ma, Dongxi
2014-09-01
Interaction is one of the key techniques of augmented reality (AR) maintenance guiding system. Because of the complexity of the maintenance guiding system's image background and the high dimensionality of gesture characteristics, the whole process of gesture recognition can be divided into three stages which are gesture segmentation, gesture characteristic feature modeling and trick recognition. In segmentation stage, for solving the misrecognition of skin-like region, a segmentation algorithm combing background mode and skin color to preclude some skin-like regions is adopted. In gesture characteristic feature modeling of image attributes stage, plenty of characteristic features are analyzed and acquired, such as structure characteristics, Hu invariant moments features and Fourier descriptor. In trick recognition stage, a classifier based on Support Vector Machine (SVM) is introduced into the augmented reality maintenance guiding process. SVM is a novel learning method based on statistical learning theory, processing academic foundation and excellent learning ability, having a lot of issues in machine learning area and special advantages in dealing with small samples, non-linear pattern recognition at high dimension. The gesture recognition of augmented reality maintenance guiding system is realized by SVM after the granulation of all the characteristic features. The experimental results of the simulation of number gesture recognition and its application in augmented reality maintenance guiding system show that the real-time performance and robustness of gesture recognition of AR maintenance guiding system can be greatly enhanced by improved SVM.
NASA Technical Reports Server (NTRS)
Rector, Tony; Peyton, Barbara; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice
2014-01-01
Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessonslearned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.
Risk analysis of maintenance ship collisions with offshore wind turbines
NASA Astrophysics Data System (ADS)
Presencia, Carla E.; Shafiee, Mahmood
2018-07-01
A large number of offshore wind farms are planned to be built in remote deep-sea areas over the next five years. Though offshore wind sites are often located away from commercial ship traffic, the increased demand for repair or replacement services leads to high traffic densities of "maintenance ships". To date, the risk analysis of collision between maintenance ship vessels and offshore wind turbines has received very little attention. In this paper, we propose a methodology to evaluate and prioritise the collision risks associated with various kinds of ships used for carrying out maintenance tasks on different subassemblies of wind turbines in an offshore wind farm. It is also studied how the risks of ship collision with wind turbines are distributed between two main types of maintenance tasks, namely corrective and preventative. The proposed model is tested on an offshore wind turbine with seventeen components requiring five kinds of ships to perform the maintenance tasks. Our results indicate that collision risks are mostly associated with maintenance of few components of the wind turbine and in particular, those undergoing a corrective maintenance (replacement). Finally, several mitigation strategies are introduced to minimise the risk of maintenance ship collisions with offshore wind turbines.
a 3d GIS Method Applied to Cataloging and Restoring: the Case of Aurelian Walls at Rome
NASA Astrophysics Data System (ADS)
Canciani, M.; Ceniccola, V.; Messi, M.; Saccone, M.; Zampilli, M.
2013-07-01
The project involves architecture, archaeology, restoration, graphic documentation and computer imaging. The objective is development of a method for documentation of an architectural feature, based on a three-dimensional model obtained through laser scanning technologies, linked to a database developed in GIS environment. The case study concerns a short section of Rome's Aurelian walls, including the Porta Latina. The city walls are Rome's largest single architectural monument, subject to continuous deterioration, modification and maintenance since their original construction beginning in 271 AD. The documentation system provides a flexible, precise and easily-applied instrument for recording the full appearance, materials, stratification palimpsest and conservation status, in order to identify restoration criteria and intervention priorities, and to monitor and control the use and conservation of the walls over time. The project began with an analysis and documentation campaign integrating direct, traditional recording methods with indirect, topographic instrument and 3D laser scanning recording. These recording systems permitted development of a geographic information system based on three-dimensional modelling of separate, individual elements, linked to a database and related to the various stratigraphic horizons, the construction techniques, the component materials and their state of degradation. The investigations of the extant wall fabric were further compared to historic documentation, from both graphic and descriptive sources. The resulting model constitutes the core of the GIS system for this specific monument. The methodology is notable for its low cost, precision, practicality and thoroughness, and can be applied to the entire Aurelian wall and to other monuments.
Normalizing effect of heroin maintenance treatment on stress-induced brain connectivity
Walter, Marc; Gerber, Hana; Seifritz, Erich; Brenneisen, Rudolf; Wiesbeck, Gerhard A.; Riecher-Rössler, Anita; Lang, Undine E.; Borgwardt, Stefan
2015-01-01
Recent evidence has shown that a single maintenance dose of heroin attenuates psychophysiological stress responses in heroin-dependent patients, probably reflecting the effectiveness of heroin-assisted therapies for the treatment of severe heroin addiction. However, the underlying neural circuitry of these effects has not yet been investigated. Using a cross-over, double-blind, vehicle-controlled design, 22 heroin-dependent and heroin-maintained outpatients from the Centre of Substance Use Disorders at the University Hospital of Psychiatry in Basel were studied after heroin and placebo administration, while 17 healthy controls from the general population were included for placebo administration only. Functional magnetic resonance imaging was used to detect brain responses to fearful faces and dynamic causal modelling was applied to compute fear-induced modulation of connectivity within the emotional face network. Stress responses were assessed by hormone releases and subjective ratings. Relative to placebo, heroin acutely reduced the fear-induced modulation of connectivity from the left fusiform gyrus to the left amygdala and from the right amygdala to the right orbitofrontal cortex in dependent patients. Both of these amygdala-related connectivity strengths were significantly increased in patients after placebo treatment (acute withdrawal) compared to healthy controls, whose connectivity estimates did not differ from those of patients after heroin injection. Moreover, we found positive correlations between the left fusiform gyrus to amygdala connectivity and different stress responses, as well as between the right amygdala to orbitofrontal cortex connectivity and levels of craving. Our findings indicate that the increased amygdala-related connectivity during fearful face processing after the placebo treatment in heroin-dependent patients transiently normalizes after acute heroin maintenance treatment. Furthermore, this study suggests that the assessment of amygdala-related connectivity during fear processing may provide a prognostic tool to assess stress levels in heroin-dependent patients and to quantify the efficacy of maintenance treatments in drug addiction. PMID:25414039
Chang, Hsueh-Yuan; Vickers, Zata M; Tong, Cindy B S
2018-04-01
Loss of crispness in apple fruit during storage reduces the fruit's fresh sensation and consumer acceptance. Apple varieties that maintain crispness thus have higher potential for longer-term consumer appeal. To efficiently phenotype crispness, several instrumental methods have been tested, but variable results were obtained when different apple varieties were assayed. To extend these studies, we assessed the extent to which instrumental measurements correlate to and predict sensory crispness, with a focus on crispness maintenance. We used an apple breeding family derived from a cross between "Honeycrisp" and "MN1764," which segregates for crispness maintenance. Three types of instrumental measurements (puncture, snapping, and mechanical-acoustic tests) and sensory evaluation were performed on fruit at harvest and after 8 weeks of cold storage. Overall, 20 genotypes from the family and the 2 parents were characterized by 19 force and acoustic measures. In general, crispness was more related to force than to acoustic measures. Force linear distance and maximum force as measured by the mechanical-acoustic test were best correlated with sensory crispness and change in crispness, respectively. The correlations varied by apple genotype. The best multiple linear regression model to predict change in sensory crispness between harvest and storage of fruit of this breeding family incorporated both force and acoustic measures. This work compared the abilities of instrumental tests to predict sensory crispness maintenance of apple fruit. The use of an instrumental method that is highly correlated to sensory crispness evaluation can enhance the efficiency and reduce the cost of measuring crispness for breeding purposes. This study showed that sensory crispness and change in crispness after storage of an apple breeding family were reliably predicted with a combination of instrumental measurements and multiple variable analyses. The strategy potentially can be applied to other apple varieties for more accurate interpretation of crispness maintenance measured instrumentally. © 2018 Wiley Periodicals, Inc.
Testing high brightness LEDs relative to application environment
NASA Astrophysics Data System (ADS)
Singer, Jeffrey; Mangum, Scott; Lundberg, John
2006-08-01
Application of light emitting diodes is expanding as the luminous output and efficiencies of these devices improve. At the same time, the number of LED package types is increasing, making it challenging to determine the appropriate device for use in lighting product designs. A range of factors should be considered when selecting a LED for an application including color coordinates, luminous efficacy, cost, lumen maintenance, application life, packaging and manufacturability. Additional complexities can be introduced as LED packages become obsolete and replacement parts must be selected. The replacement LED characteristics must be understood and assessed against the parameters of the original device, in order to determine if the change will be relatively simple or will force other end-product changes. While some characteristics are readily measured and compared, other factors, such as lumen maintenance, are difficult to verify. This paper will discuss the characteristics of a LED that should be considered during the design process as well as methods to validate these characteristics, particularly those which are not typically on data sheets or, are critical to the design and warrant additional validation. Particular attention will be given to LED lumen maintenance. While published manufacturer data typically provides temperature versus performance curves, the data may not be useful depending upon the application's operating environment. Models must be created to estimate the LED's junction temperature and degradation curve at the applied temperature in order to develop a more precise life estimate. This paper presents one approach to a LED device life and performance study designed with application environments in mind.
Kalman filter based data fusion for neutral axis tracking in wind turbine towers
NASA Astrophysics Data System (ADS)
Soman, Rohan; Malinowski, Pawel; Ostachowicz, Wieslaw; Paulsen, Uwe S.
2015-03-01
Wind energy is seen as one of the most promising solutions to man's ever increasing demands of a clean source of energy. In particular to reduce the cost of energy (COE) generated, there are efforts to increase the life-time of the wind turbines, to reduce maintenance costs and to ensure high availability. Maintenance costs may be lowered and the high availability and low repair costs ensured through the use of condition monitoring (CM) and structural health monitoring (SHM). SHM allows early detection of damage and allows maintenance planning. Furthermore, it can allow us to avoid unnecessary downtime, hence increasing the availability of the system. The present work is based on the use of neutral axis (NA) for SHM of the structure. The NA is tracked by data fusion of measured yaw angle and strain through the use of Extended Kalman Filter (EKF). The EKF allows accurate tracking even in the presence of changing ambient conditions. NA is defined as the line or plane in the section of the beam which does not experience any tensile or compressive forces when loaded. The NA is the property of the cross section of the tower and is independent of the applied loads and ambient conditions. Any change in the NA position may be used for detecting and locating the damage. The wind turbine tower has been modelled with FE software ABAQUS and validated on data from load measurements carried out on the 34m high tower of the Nordtank, NTK 500/41 wind turbine.
Endocannabinoid signaling and memory dynamics: A synaptic perspective.
Drumond, Ana; Madeira, Natália; Fonseca, Rosalina
2017-02-01
Memory acquisition is a key brain feature in which our human nature relies on. Memories evolve over time. Initially after learning, memories are labile and sensitive to disruption by the interference of concurrent events. Later on, after consolidation, memories are resistant to disruption. However, reactivation of previously consolidated memories renders them again in an unstable state and therefore susceptible to perturbation. Additionally, and depending on the characteristics of the stimuli, a parallel process may be initiated which ultimately leads to the extinction of the previously acquired response. This dynamic aspect of memory maintenance opens the possibility for an updating of previously acquired memories but it also creates several conceptual challenges. What is the time window for memory updating? What determines whether reconsolidation or extinction is triggered? In this review, we tried to re-examine the relationship between consolidation, reconsolidation and extinction, aiming for a unifying view of memory dynamics. Since cellular models of memory share common principles, we present the evidence that similar rules apply to the maintenance of synaptic plasticity. Recently, a new function of the endocannabinoid (eCB) signaling system has been described for associative forms of synaptic plasticity in amygdala synapses. The eCB system has emerged as a key modulator of memory dynamics by adjusting the outcome to stimuli intensity. We propose a key function of eCB in discriminative forms of learning by restricting associative plasticity in amygdala synapses. Since many neuropsychiatric disorders are associated with a dysregulation in memory dynamics, understanding the rules underlying memory maintenance paves the path to better clinical interventions. Copyright © 2016 Elsevier Inc. All rights reserved.
Besseling, Rut; Damen, Michiel; Tran, Thanh; Nguyen, Thanh; van den Dries, Kaspar; Oostra, Wim; Gerich, Ad
2015-10-10
Dry powder mixing is a wide spread Unit Operation in the Pharmaceutical industry. With the advent of in-line Near Infrared (NIR) Spectroscopy and Quality by Design principles, application of Process Analytical Technology to monitor Blend Uniformity (BU) is taking a more prominent role. Yet routine use of NIR for monitoring, let alone control of blending processes is not common in the industry, despite the improved process understanding and (cost) efficiency that it may offer. Method maintenance, robustness and translation to regulatory requirements have been important barriers to implement the method. This paper presents a qualitative NIR-BU method offering a convenient and compliant approach to apply BU control for routine operation and process understanding, without extensive calibration and method maintenance requirements. The method employs a moving F-test to detect the steady state of measured spectral variances and the endpoint of mixing. The fundamentals and performance characteristics of the method are first presented, followed by a description of the link to regulatory BU criteria, the method sensitivity and practical considerations. Applications in upscaling, tech transfer and commercial production are described, along with evaluation of the method performance by comparison with results from quantitative calibration models. A full application, in which end-point detection via the F-test controls the blending process of a low dose product, was successfully filed in Europe and Australia, implemented in commercial production and routinely used for about five years and more than 100 batches. Copyright © 2015 Elsevier B.V. All rights reserved.
Intra-axiom redundancies in SNOMED CT.
Dentler, Kathrin; Cornet, Ronald
2015-09-01
Intra-axiom redundancies are elements of concept definitions that are redundant as they are entailed by other elements of the concept definition. While such redundancies are harmless from a logical point of view, they make concept definitions hard to maintain, and they might lead to content-related problems when concepts evolve. The objective of this study is to develop a fully automated method to detect intra-axiom redundancies in OWL 2 EL and apply it to SNOMED Clinical Terms (SNOMED CT). We developed a software program in which we implemented, adapted and extended readily existing rules for redundancy elimination. With this, we analysed occurence of redundancy in 11 releases of SNOMED CT (January 2009 to January 2014). We used the ELK reasoner to classify SNOMED CT, and Pellet for explanation of equivalence. We analysed the completeness and soundness of the results by an in-depth examination of the identified redundant elements in the July 2012 release of SNOMED CT. To determine if concepts with redundant elements lead to maintenance issues, we analysed a small sample of solved redundancies. Analyses showed that the amount of redundantly defined concepts in SNOMED CT is consistently around 35,000. In the July 2012 version of SNOMED CT, 35,010 (12%) of the 296,433 concepts contained redundant elements in their definitions. The results of applying our method are sound and complete with respect to our evaluation. Analysis of solved redundancies suggests that redundancies in concept definitions lead to inadequate maintenance of SNOMED CT. Our analysis revealed that redundant elements are continuously introduced and removed, and that redundant elements may be overlooked when concept definitions are corrected. Applying our redundancy detection method to remove intra-axiom redundancies from the stated form of SNOMED CT and to point knowledge modellers to newly introduced redundancies can support creating and maintaining a redundancy-free version of SNOMED CT. Copyright © 2014 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simpson, L.; Britt, J.; Birkmire, R.
ITN Energy Systems, Inc., and Global Solar Energy, Inc., assisted by NREL's PV Manufacturing R&D program, have continued to advance CIGS production technology by developing trajectory-oriented predictive/control models, fault-tolerance control, control platform development, in-situ sensors, and process improvements. Modeling activities included developing physics-based and empirical models for CIGS and sputter-deposition processing, implementing model-based control, and applying predictive models to the construction of new evaporation sources and for control. Model-based control is enabled by implementing reduced or empirical models into a control platform. Reliability improvement activities include implementing preventive maintenance schedules; detecting failed sensors/equipment and reconfiguring to tinue processing; and systematicmore » development of fault prevention and reconfiguration strategies for the full range of CIGS PV production deposition processes. In-situ sensor development activities have resulted in improved control and indicated the potential for enhanced process status monitoring and control of the deposition processes. Substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control, efficiency, yield, and throughput. In large measure, these gains have been driven by process optimization, which in turn have been enabled by control and reliability improvements due to this PV Manufacturing R&D program.« less
System Modeling and Diagnostics for Liquefying-Fuel Hybrid Rockets
NASA Technical Reports Server (NTRS)
Poll, Scott; Iverson, David; Ou, Jeremy; Sanderfer, Dwight; Patterson-Hine, Ann
2003-01-01
A Hybrid Combustion Facility (HCF) was recently built at NASA Ames Research Center to study the combustion properties of a new fuel formulation that burns approximately three times faster than conventional hybrid fuels. Researchers at Ames working in the area of Integrated Vehicle Health Management recognized a good opportunity to apply IVHM techniques to a candidate technology for next generation launch systems. Five tools were selected to examine various IVHM techniques for the HCF. Three of the tools, TEAMS (Testability Engineering and Maintenance System), L2 (Livingstone2), and RODON, are model-based reasoning (or diagnostic) systems. Two other tools in this study, ICS (Interval Constraint Simulator) and IMS (Inductive Monitoring System) do not attempt to isolate the cause of the failure but may be used for fault detection. Models of varying scope and completeness were created, both qualitative and quantitative. In each of the models, the structure and behavior of the physical system are captured. In the qualitative models, the temporal aspects of the system behavior and the abstraction of sensor data are handled outside of the model and require the development of additional code. In the quantitative model, less extensive processing code is also necessary. Examples of fault diagnoses are given.
A hybrid prognostic model for multistep ahead prediction of machine condition
NASA Astrophysics Data System (ADS)
Roulias, D.; Loutas, T. H.; Kostopoulos, V.
2012-05-01
Prognostics are the future trend in condition based maintenance. In the current framework a data driven prognostic model is developed. The typical procedure of developing such a model comprises a) the selection of features which correlate well with the gradual degradation of the machine and b) the training of a mathematical tool. In this work the data are taken from a laboratory scale single stage gearbox under multi-sensor monitoring. Tests monitoring the condition of the gear pair from healthy state until total brake down following several days of continuous operation were conducted. After basic pre-processing of the derived data, an indicator that correlated well with the gearbox condition was obtained. Consecutively the time series is split in few distinguishable time regions via an intelligent data clustering scheme. Each operating region is modelled with a feed-forward artificial neural network (FFANN) scheme. The performance of the proposed model is tested by applying the system to predict the machine degradation level on unseen data. The results show the plausibility and effectiveness of the model in following the trend of the timeseries even in the case that a sudden change occurs. Moreover the model shows ability to generalise for application in similar mechanical assets.
Al Mamoon, Ishtiak; Muzahidul Islam, A K M; Baharun, Sabariah; Ahmed, Ashir; Komaki, Shozo
2016-08-01
Due to the rapid growth of wireless medical devices in near future, wireless healthcare services may face some inescapable issue such as medical spectrum scarcity, electromagnetic interference (EMI), bandwidth constraint, security and finally medical data communication model. To mitigate these issues, cognitive radio (CR) or opportunistic radio network enabled wireless technology is suitable for the upcoming wireless healthcare system. The up-to-date research on CR based healthcare has exposed some developments on EMI and spectrum problems. However, the investigation recommendation on system design and network model for CR enabled hospital is rare. Thus, this research designs a hierarchy based hybrid network architecture and network maintenance protocols for previously proposed CR hospital system, known as CogMed. In the previous study, the detail architecture of CogMed and its maintenance protocols were not present. The proposed architecture includes clustering concepts for cognitive base stations and non-medical devices. Two cluster head (CH selector equations are formulated based on priority of location, device, mobility rate of devices and number of accessible channels. In order to maintain the integrity of the proposed network model, node joining and node leaving protocols are also proposed. Finally, the simulation results show that the proposed network maintenance time is very low for emergency medical devices (average maintenance period 9.5 ms) and the re-clustering effects for different mobility enabled non-medical devices are also balanced.
NASA Technical Reports Server (NTRS)
Woodbury, Sarah K.
2008-01-01
The introduction of United Space Alliance's Human Engineering Modeling and Performance Laboratory began in early 2007 in an attempt to address the problematic workspace design issues that the Space Shuttle has imposed on technicians performing maintenance and inspection operations. The Space Shuttle was not expected to require the extensive maintenance it undergoes between flights. As a result, extensive, costly resources have been expended on workarounds and modifications to accommodate ground processing personnel. Consideration of basic human factors principles for design of maintenance is essential during the design phase of future space vehicles, facilities, and equipment. Simulation will be needed to test and validate designs before implementation.
Inventory-transportation integrated optimization for maintenance spare parts of high-speed trains
Wang, Jiaxi; Wang, Huasheng; Wang, Zhongkai; Li, Jian; Lin, Ruixi; Xiao, Jie; Wu, Jianping
2017-01-01
This paper presents a 0–1 programming model aimed at obtaining the optimal inventory policy and transportation mode for maintenance spare parts of high-speed trains. To obtain the model parameters for occasionally-replaced spare parts, a demand estimation method based on the maintenance strategies of China’s high-speed railway system is proposed. In addition, we analyse the shortage time using PERT, and then calculate the unit time shortage cost from the viewpoint of train operation revenue. Finally, a real-world case study from Shanghai Depot is conducted to demonstrate our method. Computational results offer an effective and efficient decision support for inventory managers. PMID:28472097
Zeng, Xiaohui; Peng, Liubao; Li, Jianhe; Chen, Gannong; Tan, Chongqing; Wang, Siying; Wan, Xiaomin; Ouyang, Lihui; Zhao, Ziying
2013-01-01
Continuation maintenance treatment with pemetrexed is approved by current clinical guidelines as a category 2A recommendation after induction therapy with cisplatin and pemetrexed chemotherapy (CP strategy) for patients with advanced nonsquamous non-small-cell lung cancer (NSCLC). However, the cost-effectiveness of the treatment remains unclear. We completed a trial-based assessment, from the perspective of the Chinese health care system, of the cost-effectiveness of maintenance pemetrexed treatment after a CP strategy for patients with advanced nonsquamous NSCLC. A Markov model was developed to estimate costs and benefits. It was based on a clinical trial that compared continuation maintenance pemetrexed therapy plus best supportive care (BSC) versus placebo plus BSC after a CP strategy for advanced nonsquamous NSCLC. Sensitivity analyses were conducted to assess the stability of the model. The model base case analysis suggested that continuation maintenance pemetrexed therapy after a CP strategy would increase benefits in a 1-, 2-, 5-, or 10-year time horizon, with incremental costs of $183,589.06, $126,353.16, $124,766.68, and $124,793.12 per quality-adjusted life-year gained, respectively. The most sensitive influential variable in the cost-effectiveness analysis was the utility of the progression-free survival state, followed by proportion of patients with postdiscontinuation therapy in both arms, proportion of BSC costs for PFS versus progressed survival state, and cost of pemetrexed. Probabilistic sensitivity analysis indicated that the cost-effective probability of adding continuation maintenance pemetrexed therapy to BSC was zero. One-way and probabilistic sensitivity analyses revealed that the Markov model was robust. Continuation maintenance of pemetrexed after a CP strategy for patients with advanced nonsquamous NSCLC is not cost-effective based on a recent clinical trial. Decreasing the price or adjusting the dosage of pemetrexed may be a better option for meeting the treatment demands of Chinese patients. Copyright © 2013 Elsevier HS Journals, Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Fryling, Meg
2010-11-01
Organisations often make implementation decisions with little consideration for the maintenance phase of an enterprise resource planning (ERP) system, resulting in significant recurring maintenance costs. Poor cost estimations are likely related to the lack of an appropriate framework for enterprise-wide pre-packaged software maintenance, which requires an ongoing relationship with the software vendor (Markus, M.L., Tanis, C., and Fenema, P.C., 2000. Multisite ERP implementation. CACM, 43 (4), 42-46). The end result is that critical project decisions are made with little empirical data, resulting in substantial long-term cost impacts. The product of this research is a formal dynamic simulation model that enables theory testing, scenario exploration and policy analysis. The simulation model ERPMAINT1 was developed by combining and extending existing frameworks in several research domains, and by incorporating quantitative and qualitative case study data. The ERPMAINT1 model evaluates tradeoffs between different ERP project management decisions and their impact on post-implementation total cost of ownership (TCO). Through model simulations a variety of dynamic insights were revealed that could assist ERP project managers. Major findings from the simulation show that upfront investments in mentoring and system exposure translate to long-term cost savings. The findings also indicate that in addition to customisations, add-ons have a significant impact on TCO.
ERIC Educational Resources Information Center
Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.
THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE COOLING SYSTEM AND TO PROVIDE A DESCRIPTION OF HEAVY TIRES AND WHEELS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) THEORY OF THE COOLING SYSTEM, (2) COOLING SYSTEM COMPONENTS, (3) MAINTENANCE TIPS (COOLING SYSTEM), (4)…
Software For Graphical Representation Of A Network
NASA Technical Reports Server (NTRS)
Mcallister, R. William; Mclellan, James P.
1993-01-01
System Visualization Tool (SVT) computer program developed to provide systems engineers with means of graphically representing networks. Generates diagrams illustrating structures and states of networks defined by users. Provides systems engineers powerful tool simplifing analysis of requirements and testing and maintenance of complex software-controlled systems. Employs visual models supporting analysis of chronological sequences of requirements, simulation data, and related software functions. Applied to pneumatic, hydraulic, and propellant-distribution networks. Used to define and view arbitrary configurations of such major hardware components of system as propellant tanks, valves, propellant lines, and engines. Also graphically displays status of each component. Advantage of SVT: utilizes visual cues to represent configuration of each component within network. Written in Turbo Pascal(R), version 5.0.
Teleoperator Maneuvering System (TMS) benefits assessment study. Volume 1: Executive summary
NASA Technical Reports Server (NTRS)
1983-01-01
Teleoperator Maneuvering System (TMS) versus integral spacecraft propulsion, spacecraft maintenance, cost benefits, launch prices, integral propulsion length penalties, remote maintenance versus EVA, potential weight reduction benefits, basing mode, mission models and payload requirements, and program profitability are discussed.
NASA Astrophysics Data System (ADS)
Antonov, Anca Elena; Buica, Georgeta; Darabont, Doru Costin; Beiu, Constantin
2015-07-01
For use of work equipment having the economic performance and the highest level of safety, it must be ensured that it complies with the conditions set by the manufacturer in terms of putting into service, use and maintenance operations, ensuring appropriate technical and environmental requirements, including appropriate measures and means of protection. The research aimed to identify and analyze the occupational hazards associated to maintenance operations, in terms of the history of the adjustments, maintenance, cleaning and repair, including the case that occur after the incidents, capital repairs and upgrades. The results of the research consisted in the development of recommendations on the effective management of maintenance activities of work equipment and a software model to enable an efficient management of maintenance, as a tool for occupational hazards in companies - premise for increasing the competitiveness of employers in the market economy.
The purpose of this SOP is to detail the operation and maintenance of an Instruments, SA Inc., Jobin-Yvon Model 70 (JY-70) inductively coupled plasma atomic emissions spectrometry (ICP-AES). This procedure was followed to ensure consistent data retrieval during the Arizona NHEXA...
Why and for Whom May Coping Planning Have Adverse Effects? A Moderated Mediation Analysis.
Inauen, Jennifer; Stocker, Andrea; Scholz, Urte
2018-05-09
Coping planning, the formation of plans to overcome behavioral barriers is assumed to promote health behavior maintenance, but the literature on this is inconsistent. In this study, we aimed to investigate the mechanisms of a coping planning intervention that adversely affected maintained safe water consumption. We also explored perceived behavioral difficulty as a potential moderator of coping planning interventions. In the second phase of a cluster-randomised trial, households (N = 177 analyzed) were randomly allocated to a coping planning intervention or a comparison group (repetition of interventions from first intervention phase). Safe water consumption, the mechanisms of coping planning, and perceived difficulty were measured pre-post. The data were analyzed using mediation and moderated mediation analysis. Changes in behavioral intention mediated the intervention effects on behavioral maintenance (b = -0.36, 95% CI [-0.91, -0.03]). Changes in perceived coping planning (b = 0.08, 95% CI [-0.12, 0.34]), and maintenance self-efficacy (b = -0.13, 95% CI [-0.45, 0.01]) did not mediate the effects. Prior perceived difficulty moderated the coping planning intervention effects on maintenance via intention. Coping planning may decrease motivation for health behavior maintenance for persons who experienced few barriers prior to the planning intervention. © 2018 The International Association of Applied Psychology.
Mathematical Methods of Managing Economic Sustainability of the Construction Company
NASA Astrophysics Data System (ADS)
Kostuchenko, Vasiliy; Zdanov, Andrej; Rodionov, Anatolij
2017-10-01
This article presents a long-term research in developing innovative mathematical techniques of managing the contractor’s economic sustainability proven by some experimental studies. The article aims at presenting some practical results of applying these techniques to the scientific community. This research presents a description of some applied mathematical models, views, and some results of their practical application in the applied field for the purposes of evaluating operational sustainability and minimizing losses in the process of managing the company. The authors have put the technology they have developed to practical use, and the article presents the results of such application. The authors have put the developed technology to practical use. Company management also means the management of power consumption, which is highly vital both for the construction and maintenance of buildings and structures. The articles also dwell on some possible improvements of managing energy consumption within the framework of the general management of company’s economic sustainability, because these phenomena have a tight organic interdependence. The authors continue researching this direction in order to improve the production efficiency of the proposed technologies as well as to eliminate some drawbacks they have spotted.
DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY SITE CAPSULE
In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...
DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY - ITER
In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...
75 FR 34004 - State Cemetery Grants
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-16
... architectural design codes that apply to grant applicants, we decided to update those references in a separate.... 39.63 Architectural design standards. Subpart C--Operation and Maintenance Projects Grant... acquisition, design and planning, earth moving, landscaping, construction, and provision of initial operating...