Repair Costs Research Articles

Modelling and Diagnosis of Hybrid Dynamic Systems by a Multi-Model Approach

Fault diagnosis is an essential task in ensuring the smooth operation of complex dynamic systems. The consequences of faults can be serious, leading to loss of life, harmful emissions to the environment, high repair costs and economic losses caused by unplanned production line stoppages. The work developed in this paper concerns the modeling and diagnosis of faults (sensor faults, system faults, actuator faults) in hybrid dynamic systems using our multi-model approach (which combines two sub-models, one continuous and the other discrete). The aim is to integrate three well-known tools in the literature: the Bond Graph, the Observer and the Timed Automata, to design a global diagnostic model. The hybrid dynamic system is modeled by connecting the tools for the continuous part, i.e. the bond graph and the observer, to the timed automata for the discrete part. The resulting model is used for fault diagnosis in two stages: The first is fault detection by analyzing the residuals generated by the system output and that of the observer. The second step involves fault localization, which results from analysis of the signature matrix and temporal identification of the system. The proposed method combines the advantages of these tools to obtain the best performance, particularly in the fault location phase. The simulation results prove the effectiveness of the proposed model for the hybrid dynamic system. Moreover, these results also evaluate the performance of the proposed diagnostic approach while reducing non-detections, detection delays and false alarms.

Quay Crane Performance Improvement and Lifecycle Extension: Retrofit Determination – A Case Study

Quay cranes (QCs) are critical equipment in Container Terminals and their performance determines the port operation efficiency in meeting operational Key Performance Indicators (KPIs). Considering 30-year lifespan of QCs and deteriorating reliability of the electrical control system, planning for timely retrofit of the QCs is critical. The paper aims to present a case study on how the performance of a batch of QCs, having more than 50% remaining lifespan, were analyzed and concluded to be retrofitted to address their deteriorating performance, high maintenance cost and obsolescence. The study methodology is based on quantitative data and employed a prospective longitudinal panel research design over sixteen years. eleven years of pre-retrofit and five years of post-retrofit operations, maintenance and financial data were collected. Convenient sampling technique was selected in this study as the QCs identified as samples were having reliability issues. The Correlation Analysis indicates strong positive correlation of more than 90% between Mean Time Between Failure, Mean Move Between Failure and Reliability KPIs. These KPIs have moderate positive correlations of about 50% with Availability KPI. These 4 KPIs have strong negative correlation of between -50% and -85% with Mean Time to Repair, Maintenance and Breakdown Repair Cost indicating performance degradation but increased maintenance and repair costs as shown by Trend Analysis. The 11-year preretrofit data has identified parameters to determine the QC retrofit prediction. The KPIs, obsolescence status, maintenance and breakdown repair cost can be used as the inputs to the future QC Retrofit Prediction Model development.

INTERNAL CONTROL ON MILITARY ASSETS ACCORDING TO MILK AL-DAULAH IN ISLAMIC ECONOMIC LAW

This article aims to examine the internal control system of national military assets in Indonesia at the Kuta Alam Banda Aceh barracks, reviewed according to the concept of milk al-daulah. The approach taken by the author is a juridical-empirical study. The research findings indicate that to address issues in the internal control system of assets in the Indonesian National Army (TNI) at the Kuta Alam Banda Aceh barracks, a holistic approach is required to effectively tackle existing challenges. It is crucial to update and refine the inventory process to ensure that asset data is more accurate and current. Implementing an integrated, technology-based asset management system will facilitate tracking and monitoring. Furthermore, asset maintenance should be scheduled regularly and its implementation should be ensured to prevent damage that could increase repair costs. Enhancements in surveillance technology, such as modern CCTV and access control systems, are essential to reduce the risk of theft and damage. Compliance with policies should be strengthened through intensive training and consistent enforcement to ensure procedures are properly followed. Risk management also needs improvement with more effective and proactive mitigation strategies. Additionally, the use of advanced technology can support efficiency in asset management and reporting. Transparency should be increased by providing clear and accessible reporting mechanisms, while budget management should be improved to ensure efficient allocation. Regular personnel training is important to keep their skills relevant, and routine audits and evaluations should be conducted to maintain the effectiveness of the internal control system.

Strength optimization of transverse retrofitting device for seismic isolated bridge based on seismic repair cost ratio

At present, the application of seismically isolated bridges is widespread. However, the elongation of the period of isolated bridges often leads to large displacements in the superstructure and significant residual displacements after earthquakes, which results in high repair costs or even bridge collapse. Therefore, various retrofitting measures for laminated rubber-bearing isolated bridges have emerged. The selection and design of these retrofitting measures are crucial to the response of bridges. In this study, three types of retrofitting devices are considered: concrete shear key, steel cable, and superelastic shape memory alloy (SMA) cable. The performance of different retrofitting devices is compared using the annualized seismic repair cost ratio (ASRCR) analysis and incremental dynamic analysis (IDA). Then the ASRCR analysis based on probability is used to optimize the strength of the retrofitting device. The results demonstrate that SMA cables and steel cables demonstrate similar effectiveness in reducing the fragility of bearings, but the superior self-centering ability of SMA cable significantly reduces the residual displacements of bearings. Furthermore, a mathematical model is developed to evaluate the economic benefits of seismic isolated bridges equipped with SMA cables and the strength of SMA cables can be designed rapidly by this model.

Repair and maintenance of fixed assets

Federal Accounting Standard 26/2020 “Capital investments” has established rules for reflecting the cost of repairing fixed assets — if the repair is of a capital nature, the cost of it increases the cost of the repaired object, i.e. it is capitalized, and in the case when the repair is of a current nature or relates to the ongoing maintenance of fixed assets (when it is carried out with a frequency not exceeding 12 months), the costs of conducting them are not included in capital investments, but are written off as expenses of the current period. The non-governmental accounting regulator “Accounting Methodological Center” in its Recommendations sets out its position on the reflection of repair and maintenance costs. During the research, we used such methods as analysis and synthesis, comparison, grouping method, analogy method, logical approach, systematic approach. As a result of the conducted research, this article, in particular, presents additional proposals clarifying the wording of both the FSB 26/2020 and the Recommendations of the NBU BMC. In addition, in this paper, suggestions are made to improve the content of accounting statements. The results of this study will be of interest to a wide range of readers studying various problems of modern Russian and foreign accounting, and can also be used in the educational process of higher educational institutions.

Failure Consequence Cost Analysis of Wave Energy Converters—Component Failures, Site Impacts, and Maintenance Interval Scenarios

In the early stages of developing wave energy converter (WEC) projects, a quantitative assessment of component failure consequence costs is essential. The WEC types, deployment site features, and accessibility should all be carefully considered. This study introduces an operation and maintenance failure consequence cost (O&M-FC) model, distinct from conventional O&M models. The model is illustrated with case studies at three energetic Atlantic sites, each of which considers two types of generic floating WECs: a 300 kW point absorber (PA) with a hydraulic power-take-off (PTO) and a 1000 kW oscillating water column (OWC) with an air-wells-turbine PTO. This study compares 39 failure modes for PA and 27 for OWC in terms of direct repair costs and indirect lost production costs, examining the impact of location accessibility, capacity factors, and the mean annual energy production. The discussion revolves around the sensitive parameters. Recommendations for failure mitigations are presented, and the impact of planned maintenance (PM) during the operational phase is examined for 20 MW PA and OWC WEC projects. For a given WEC type, the method thoroughly evaluates how the location affects performance metrics. It offers a decision-making tool for determining optimal PM intervals to meet targets such as O&M costs, operating profit, or availability.

Performance assessment of alko-amine corrosion inhibitors for use as an admixture in reinforced concrete structures: Experimental investigation and mechanism of action

Corrosion in reinforced concrete (RC) is a major issue in the construction industry, giving rise to structural failure, huge repair costs, and safety concerns. To mitigate RC corrosion, chemical corrosion inhibitors (CCI) are commonly used. This study aims to investigate the performance of different alko-amine CCIs for corrosion control in reinforced concrete (RC) structures subjected to chloride-rich conditions. The experimental program was divided into two levels: investigations comprised of quick testing on bare rebars, suitable for industries, and analysis which comprised of electrochemical investigation in simulated concrete pore solution and testing on rebar embedded in concrete, suitable for research labs. The interaction between inhibitors and steel was examined through surface analytical techniques such as AFM and XPS. Finally, the inhibition mechanism for the CCI was proposed. The alko-amines were found to show a strong dependence on their molecular structure for the formed film integrity. Monoethanolamine (MEA) and methyl ethanolamine (MeEA) formed a denser and more uniform film compared to dimethyl ethanolamine (DMeEA) and ethyl monoethanolamine (EMEA). MeEA showed the highest inhibition efficiency in both simulated pore solution environments and when used as an admixture in RC.

Quantifying the effect of pulse-like ground motions on the seismic design of SMA restrained isolation bridges using probabilistic repair cost method

The shape memory alloy (SMA) restrainer serves as an effective but expensive bridge restraining device. However, the impact of pulse effect on SMA design approach under pulse-like ground motions (PLGM) has not been fully quantified in previous studies, which hinders its application in near-fault regions. Therefore, based on the risk probability assessment method throughout the entire life cycle, by accounting for the comprehensive repair cost of each component damage, this paper introduces a parameter design method for SMA restrainer of near-fault bridges that considers structural parameters, pulse parameters, and economic indicators. Firstly, the repair cost ratio (RCR) of bridge system, which means the expenses for repairs expressed as a proportion of bridge replacement costs, was regarded as the life-time optimization goal and overall performance indicator. Secondly, by accounting for near-fault effects, the relationship between RCR and SMA design parameters was established by convolution algorithm of probabilistic seismic hazard analysis, demand analysis and capacity analysis. A novel probabilistic seismic demand model was utilized to quickly determine the RCR of the bridge system under PLGM. Finally, the influence of pulse period on the rational design parameter of SMA restrainer was comprehensively investigated by RCR-based method. A seismic isolation arch bridge was selected as the illustrated case in this article. The results indicate that the rational design parameters of SMA exhibit a pattern of initially rising, then falling as the pulse period increases, reaching the peak value when the pulse period approaches bridge fundamental period. Moreover, the price parameter of SMA significantly affect the optimal design parameters, and the effective range is also recommended.

Multi-hazard life-cycle consequence analysis of deteriorating engineering systems

Probabilistic life-cycle consequence (LCCon) analysis (e.g., assessment of repair costs, downtime, or casualties over an asset’s service life) can enable optimal life-cycle management of critical assets under uncertainties. This can lead to effective risk-informed decision-making for future disaster management (i.e., risk mitigation and/or resilience-enhancing strategies/policies) implementation. Nevertheless, despite recent advances in understanding, modeling, and quantifying multiple-hazard (or multi-hazard) interactions, most available LCCon analytical formulations fail to accurately compute the exacerbated consequences which may stem from incomplete or absent repair actions between different interacting hazard events. This paper introduces a discrete-time, discrete-state Markovian framework for efficient multi-hazard LCCon analysis of deteriorating engineering systems (e.g., buildings, infrastructure components) that appropriately accounts for complex interactions between natural hazard events and their effects on a system’s performance. The Markovian assumption is used to model the probability of a system being in any performance level (i.e., limit state) after multiple hazard events inducing either instantaneous and/or gradual deterioration and after potential repair actions through implementing stochastic (transition) matrices. LCCon estimates are then obtained by combining limit state probabilties with suitable system-level consequence models in a computationally efficient manner. The proposed framework is illustrated for two case studies subject to earthquake and flood events as well as environment-induced corrosion during their service life. The first is a reinforced concrete building and the second is a simple transportation road network with a reinforced concrete bridge.

A Nationwide Analysis of Complications, Reoperations and Cost of Wide-Awake Flexor Tendon Repairs.

Some papers suggest that wide-awake flexor tendon repair (FTR) may reduce rates of postoperative tendon gapping and rupture due to improved intraoperative testing of the repair. The current study is a nationwide cohort study comparing FTRs performed wide-awake and with traditional anesthesia. Patients undergoing zone II FTR between 2010-2022 were identified in PearlDiver. Exclusion criteria were other tendon repairs, concomitant treatment for vascular injury, fracture, dislocation or amputation, inpatient or office surgery, age <18 years and <1 year of follow-up. Patients were stratified by anesthesia technique: traditional anesthesia (general anesthesia, monitored anesthesia care, regional blocks) or wide-awake. Patients were matched based on age, sex, Elixhauser Comorbidity Index (ECI) score, geographical region, insurance coverage, number of tendon repairs and presence of concomitant nerve repair. 30-day wound complications, emergency department visits and readmissions and 1-year reoperations were identified. Total reimbursement for surgery was determined. Each matched cohort included 2,563 patients. Wide-awake patients had fewer 30-day emergency department visits (2.7% vs 4.8%). There were no differences in 30-day wound complications or readmissions. There was no difference in 1-year reoperations for rupture or for stiffness. Multivariable linear regression identified wide-awake surgery to be a significantly associated with lower total reimbursement. Performing digital FTR using wide-awake techniques can reduce costs, but the hypothesis that wide-awake repairs may reduce rates of tendon rupture was not supported by the current study.

Utility of 3D printing in ship repairs

With a growing focus on Sustainable Development Goals 2030, sustainability has become crucial in the shipping industry. Disruptive technologies like 3D printing can reduce manufacturing and operating costs, ensuring a robust spare supply chain for ships and offshore platforms. This technology can manufacture complex shapes, aiding in repairs and maintenance without requiring extensive cutting and welding. However, the unique and non-repetitive nature of ship repairs has hindered automation in this sector. This paper examines the utility of 3D printing in ship repairs, aiming to reduce repair costs and time while enhancing sustainability. The study shows that numerous advantages exist in using this technology in the shipping industry. However, its usage needs to be facilitated with adequate public awareness, preparation of procedures for manufacturing 3D printed parts, and standardization of 3D printers. Highlights Sustainability has become an important aspect in the shipping industry Disruptive technologies like 3-D printing can help achieve the desired sustainability Use of 3D printers for ship repairs can improve availability of ships Use of 3D printing for ship spares requires manufacturing procedures to be specified by the classification societies

Advancing sustainability: An integrated decision support framework for fleet selection in open pit mining construction

The process of selecting and configuring equipment fleets for open-pit mining is complex, requiring consideration of both quantitative and qualitative criteria. This paper presents a novel comprehensive framework for selecting loading/hauling fleets in open-pit mining projects. Through an extensive review of the literature, a total of 21 selection criteria are initially identified. With guidance from local experts, these criteria are shortlisted into five primary groups: site conditions, managerial, social, and environmental criteria. The ranking of the identified selection criteria is carried out by employing the analytical hierarchy process (AHP) and multi-attribute utility theory (MAUT) methods, utilizing a questionnaire survey. The most crucial criteria in selecting loading/hauling equipment are identified as the equipment's operating cost, productivity, repair and maintenance costs, and soil condition. An optimization module is developed to optimize the selected fleet, while adhering to sustainability principles and project constraints. The optimization module considers social, economic, and environmental sustainability variables to determine the optimal number, size, type, and capacity of fleets needed to complete the work within the allotted time. As a case study, the proposed framework is validated by experts in these types of projects. The framework's ability to effectively select fleet units for sustainable loading/hauling fleet is confirmed through this validation method.

Medical Equipment Aging

As demonstrated in the first article of this series, some medical equipment types exhibit clear, progressive deterioration with age, whereas some others do not. Regardless of its aging behavior, equipment will eventually be replaced and disposed of for a variety of reasons—eg, its repair cost has become unjustifiable, it is no longer possible to repair, or its usefulness has been superseded by newer technologies. Although it is not possible to pinpoint the exact cause of each replacement or disposal, it is useful to understand when such action takes place during the equipment’s lifespan because this can help healthcare delivery organizations to better plan and conserve its capital resources while satisfying the needs and desires of their staff to provide safe and high-quality care. The results of an analysis of the disposal pattern of ~340 thousand pieces of equipment in the period of 30+ years show age is not the primary determinant for replacement or disposal. Most equipment is deployed well past the respective depreciation period and the end-of-life or end-of-support dates declared by their respective manufacturers, without significant negative impacts on patient care. In fact, the life expectancies estimated from the disposal data are typically double of American Hospital Association’s estimated useful lives. Such accomplishment is a testimony of the extraordinary efforts made by clinical engineering/healthcare technology management professionals in keeping equipment safe and reliable in the most cost-effective manner for a very long time.

『스마트상점 기술 도입』이 소상공인 점포의 매출과 만족도에 미치는 영향

This study decomposes the local gap through the oaxaca factor analysis to find out how differences in housing prices affect the management costs with data the average value of three-year management costs between 2014 and 2016 to 536 complexes in three Gangnam and Gangbuk districts in Seoul. The results of the analysis of 290 complexes in three Gangnam and 246 complexes in three Gangbuk districts are as follows. First, housing prices did not affect administrative costs within the region, but were variables that affected data pooling. Second, when compared with the three Gangnam districts, the results of the characteristic coefficient, which can be explained by the characteristics of the complex and the external environment, showed that the gap in the management cost increased when the number of security personnel, repair and maintenance costs, elevator maintenance cost, floor area ratio, and 60m2 or more to 85m2. Third, the factors behind the gap between Gangnam 3 districts, which have higher housing prices than Gangbuk 3 districts, were confirmed to be the number of security personnel, repair costs, floor area ratio and elevator maintenance costs, and the higher the size and income of their holdings, the more they lived in Gangnam 3 districts, where local infrastructure was expanded, causing social inequality due to differences in housing welfare, such as safety, comfort and convenience.

Building Roof Covering Materials for Residential and Commercial: Comparison and Best Choices

Choosing the right roofing material is an important aspect of building design and construction. Both residential and commercial buildings have roof-related needs. But basically, the selection of roofing materials is not only for protection from but also based on energy efficiency, aesthetics, and longevity of the building. In addition, the design of roof shape selection must be done carefully because the wrong selection can cause rainwater seepage or leakage on the roof and high repair costs. This research aims to explore by comparing the characteristics of roof covering materials and provide the best choice based on needs. The research method used is a qualitative research method with the stages carried out, namely data collection techniques, sample determination, data analysis and research conclusions. Based on the analysis, it is concluded that for residential houses, tile roofs and concrete deck roofs are the best choice because they offer an optimal combination of aesthetics, durability, energy efficiency, and cost that is suitable for the Indonesian climate. While for commercial buildings, metal tile roof is an excellent choice due to its durability, energy efficiency, and modern aesthetics that suit the needs of commercial buildings.

Quality and Pricing Decisions in a Dual-Channel Closed-Loop Supply Chain Considering Imperfect Product Recycling

Level of quality not only affects demand but also affects the proportion of imperfect products and then affects profit. This paper takes the quality level as a decision variable, considers both the consumer demand and the recovery of imperfect products in a dual-channel closed-loop supply chain (CLSC), and studies the significance of a revenue-sharing contract for coordination. The results show that the relationship between the optimal price and the quality level is affected by the repair cost of imperfect products and that the consumer’s attention to price and quality affects the trend of the overall profit with the quality level. In some cases, simply improving the quality level cannot expand the demand and is not even conducive to the improvement of green supply chain profits. It is also found that in both centralized and decentralized scenarios, coordination contracts can effectively motivate retailers to collect waste and help improve the economic efficiency of green supply chains.

Research study of passenger cars repair costs depending on the vehicle make, type of spare parts and the entity providing the service

The high number of road accidents has significant social importance, both in the context of households and enterprises, because each vehicle damage entails financial outlays related to the repair of damaged vehicles. This article analyses the most common types of vehicle damage occurring in road traffic. The object of the research were the vehicles most frequently purchased in Poland in 2022. The research process involved numerical experiment method using the AUDATEX system to determine costs enabling to repair such damage. The analyses take into account various repair options, such as: Authorized Service Station, independent workshop, and conditions proposed by insurance companies in Poland. The research showed cost dependencies between variables such as the vehicle brand, the type of spare parts and the entity providing the service.

Integration of Internet of Things (IoT) Technology in the Management of Educational Facilities and Infrastructure

Internet of Things (IoT) technology has developed rapidly and has had a significant impact on various sectors, including education. The integration of IoT in the management of educational facilities and infrastructure offers the potential to improve the efficiency, monitoring, and maintenance of facilities in real time. In this digital era, the need for a smarter and more responsive management system is very important to support an effective and sustainable teaching and learning process. This research aims to analyze the potential and implementation of IoT technology in the management of educational facilities and infrastructure. The main focus is to identify the benefits, challenges, and impact of implementing IoT on operational efficiency, rationality, and quality of educational services. This research uses a qualitative approach with a case study method. The research results show that the integration of IoT in the management of educational facilities and infrastructure can increase operational efficiency through automating facility monitoring and maintenance. For example, IoT sensors enable early detection of damage and maintenance needs, which can reduce repair costs and operational downtime. Apart from that, IoT also improves security through sensor-based surveillance systems and sophisticated data analytics. However, this research also identified several challenges, such as high initial costs, the need for reliable network infrastructure, and the need for special training for staff to operate this technology. The conclusion of this research explains that the integration of IoT technology in the management of educational facilities and infrastructure shows great potential to increase the efficiency and quality of educational services. Although there are challenges to overcome, the benefits gained from implementing IoT are much more effective. A mature implementation strategy and support from various parties is needed to ensure the success of this integration.

Cost analysis of open versus robot-assisted ventral hernia repair – a retrospective cohort study

BackgroundRobot-assisted ventral hernia repair is associated with decreased length of stay and lower complication rates compared with open repair, but acquisition and maintenance of the robotic system is costly. The aim of this was study was to compare the procedure-specific cost of robot-assisted and open ventral and incisional hernia repair including cost of procedure-related readmissions and reoperations within 90 days postoperatively.MethodsSingle-center retrospective cohort study of 100 patients undergoing robot-assisted ventral hernia. Patients were propensity-score matched 1:1 with 100 patients undergoing open repairs on age, type of hernia (primary/incisional), and horizontal defect size. The primary outcome of the study was the total cost per procedure in Euros including the cost of a robotic approach, extra ports, mesh, tackers, length of stay, length of readmission, and operative reintervention. The cost of the robot itself was not included in the cost calculation.ResultsThe mean length of stay was 0.3 days for patients undergoing robot-assisted ventral hernia repair, which was significantly shorter compared with 2.1 days for patients undergoing open repair, P < 0.005. The readmission rate was 4% for patients undergoing robot-assisted ventral hernia repairs and was significantly lower compared with open repairs (17%), P = 0.006. The mean total cost of all robot-assisted ventral and incisional hernia repairs was 1,094 euro compared with 1,483 euro for open repairs, P = 0.123. The total cost of a robot-assisted incisional hernia repair was significantly lower (1,134 euros) compared with open ventral hernia repair (2,169 euros), P = 0.005.ConclusionsIn a Danish cohort of patients with incisional hernia, robot-assisted incisional hernia repair was more cost-effective than an open repair due to shortened length of stay, and lower rates of readmission and reintervention within 90 days.

ИНФОРМАЦИОННО-ДИАГНОСТИЧЕСКИЕ СРЕДСТВА ДЛЯ СЕЛЬСКОХОЗЯЙСТВЕННОЙ ТЕХНИКИ

The issues of assessing the improvement of the efficiency of agricultural domestic machinery according to the criteria of adaptability to maintenance and diagnostics and the development of measures to improve it are relevant, as they have a significant impact on reliability and total cost of ownership and resource savings during operation. The costs of maintenance and repair and losses from equipment downtime depend on the level of equipment adaptability to maintenance and diagnostics. (Research purpose) The research purpose is substantiating the development of additional information and diagnostic tools to improve the efficiency of agricultural machinery. (Materials and methods) Conducted an analysis and description of the developed tools for diagnosing agricultural machinery. We have studied similar control and diagnostic equipment manufactured by third-party manufacturers for agricultural machinery. We examined the distinctive features of our own developments and reflected the need to diagnose specific parameters. The possibilities of analyzing the received information using artificial intelligence algorithms were described. (Results and discussion) Were designed in special engineering software and the first prototypes of these technical means were assembled. Conducted 3D modeling of these devices. We performed tests that proved the possibility of developing such digital diagnostic devices for agricultural machinery, justified their effectiveness based on the data obtained. Proposed modernization of a number of systems. (Conclusions) Analyzed the results of the work of information and diagnostic devices. We collected materials on modern methods of diagnosing equipment. We have determined the further development of the direction of work for better diagnostics of components and assemblies of agricultural machinery. One of the proposed directions is the work on the adaptation of artificial intelligence algorithms for the diagnosis of agricultural machinery.