Maintenance Costs Of Facilities Research Articles

Social Infrastructure of Soviet Enterprises in the 1950s-1980s: Sources and Mechanisms of Financing (Example of Chelyabinsk Tractor Plant)

The Sources and Mechanisms of Financing the Social Infrastructure of the Chelyabinsk Tractor Plant in the 1950s-1980s. This study examines the sources and mechanisms of financing the social infrastructure of the Chelyabinsk Tractor Plant, a large Soviet industrial enterprise, during the period of 1950s-1980s. The research is based on archival documents from the plant and its trade union organization, which are stored in the United State Archive of the Chelyabinsk Region. It was found that the plant had a significant amount of assets, including housing and a network of social, cultural, and sports facilities. Financing the social infra-structure of Soviet enterprises was a complex system that involved multiple independent sources. The plant made direct payments from its economic stimulation funds, covered the maintenance costs of various facilities transferred to the trade union organization, and covered losses from the housing and communal services system. In addition, funding for these facilities also came from the state budget, social insurance budget, trade union organization budget, targeted subsidies from the All-Russian Central Council of Trade Unions, revenues from self-supporting cultural and sports institutions, and others. The Chelyabinsk Tractor Plant was required to allocate up to 10 % of its profits towards maintaining its social infra-structure, while other sources of funding con-tributed comparable amounts.

Perception of the Transition to a Zero-Emission Economy in the Opinion of Polish and Foreign Students: A Comparative Analysis

Renewable energy sources serve as an alternative to conventional energy sources, with the main advantages being their inexhaustible nature and the absence of or significant reduction in greenhouse gas emissions. On the other hand, the development of energy production utilising renewable sources remains controversial, primarily because of the high initial costs of RES investment projects and the carbon footprint during the production phase of RES facilities. However, these appear to be gradually offset by the many benefits that outweigh the initial RES facility maintenance costs. Unsurprisingly, European Union (EU) countries are at the forefront of the transition to a low-emission economy. This is evidenced by such things as the 22% decrease in greenhouse gas emissions in the Member States, achieved despite a 58% increase in gross domestic product (GDP) between 1990 and 2017. Nonetheless, the use of renewable energy sources, such as solar, wind, water, etc., is much more expensive than burning fossil fuels. It must be stressed that the European Union’s success in this regard is influenced by the actions taken by all Member States to implement the European Green Deal and their individual targets. Furthermore, the transition to a zero-emission economy is also the result of the informed participation and involvement of all European Community residents. Therefore, there exists a need for education on renewable energy sources to facilitate the transition to a zero-emission economy in European Union countries. This education should primarily target young people, whose critical choices will shape this area in the future. It is the knowledge and awareness of young people that will largely determine whether it will be possible to limit greenhouse gas emissions by 2050. This article aimed to determine how Polish and foreign students view the transition to a zero-emission economy. The article places a special emphasis on renewable energy sources as a key factor in shaping national security in terms of sustainable ecology and friendly social development. The aim of the study was achieved through a research process using theoretical and empirical research methods. To that end, the subject literature and current legislation on renewable energy sources were analysed. Moreover, a survey was conducted among Polish and foreign students living in Poland. The analysis of the research results made it possible to formulate recommendations on how to shape national security in terms of sustainable ecology and friendly social development.

Filtering device for improving the quality of cooling water in turbine generator of Sihwa Tidal Power Plant

The turbine generator cooling water system of Sihwa Tidal Power Plant is an economical system in which the cooling water cools the turbine generator through a circulation pump and the rising temperature recirculates heat exchange with seawater through a surface cooler However, as the cooling water facility continues to operate and a long period of time passes, the cooling water quality in the piping deteriorates. In particular, increasing the concentration of Fe ions in the coolant may promote corrosion of circulating pipes, which may reduce the stability of the water turbine generator operation. Even if the coolant whose water quality has deteriorated is replaced, additional cleaning agents must be treated, but chemical treatment was difficult due to concerns over pipe damage. To overcome this, a filtering device for improving the water quality of cooling water was applied. Through the application of filtering devices for about a month, the water quality was improved by reducing the concentration of cooling water Fe ions by about 70%, and the facility maintenance cost was reduced by about $110,000 per year. We can greatly contribute to maintaining the economical cooling water system and securing the operational stability of water turbine generators by applying the cooling water filter.

Research on Intelligent Monitoring of Fire Safety and Fire Rescue Plan for Tunnel Operation under Quasi-Unattended Background

Tunnel structures account for la large proportion of the structures in mountain highway transportation systems. Most tunnels are located in remote areas in which the geological conditions are complex and harsh and in which the layout of the management facilities along the way is complex. Thus, the management and maintenance costs of various facilities are expensive, the cost of fire safety operations and management is high, and disaster prevention and rescue have a difficult time meeting the objective requirements. Therefore, it is urgent to carry out research on quasi-unmanned operations and intelligent remote monitoring. This study firstly proposes a fire safety intelligent monitoring framework for quasi-unattended tunnels. By making full use of various intelligent sensor monitoring data in the tunnel, the tunnel operation status can be grasped in real time. Then, a fire safety evaluation model can be established through the analytic hierarchy process (AHP), and, based on the monitoring data, the AHP model parameters can be evaluated to realize the real-time evaluation and management of tunnel fire safety. Finally, on the basis of the fire safety intelligent monitoring system and the fire safety evaluation system, an adaptive fire rescue plan formulation scheme is proposed for the quasi-unattended tunnels so as to provide guaranteed support for the rapid automatic response of tunnel fire protection and to provide technical data support for the design and realization of intelligent and efficient tunnel management

MP49-08 SHANGRING VERSUS THE MOGEN CLAMP FOR EARLY INFANT MALE CIRCUMCISION (EIMC): A COST-COMPARATIVE ANALYSIS IN KENYA, TANZANIA AND UGANDA

You have accessJournal of UrologyCME1 Apr 2023MP49-08 SHANGRING VERSUS THE MOGEN CLAMP FOR EARLY INFANT MALE CIRCUMCISION (EIMC): A COST-COMPARATIVE ANALYSIS IN KENYA, TANZANIA AND UGANDA Mary O. Strasser, Lina Posada, Nahid Punjani, Spyridon Basourakos, Godfrey Kigozi, Quentin Awori, Alice Christensen, Mark Barone, Karla Ballman, Marc Goldstein, Alvin Mushlin, Philip Li, and Richard K. Lee Mary O. StrasserMary O. Strasser More articles by this author , Lina PosadaLina Posada More articles by this author , Nahid PunjaniNahid Punjani More articles by this author , Spyridon BasourakosSpyridon Basourakos More articles by this author , Godfrey KigoziGodfrey Kigozi More articles by this author , Quentin AworiQuentin Awori More articles by this author , Alice ChristensenAlice Christensen More articles by this author , Mark BaroneMark Barone More articles by this author , Karla BallmanKarla Ballman More articles by this author , Marc GoldsteinMarc Goldstein More articles by this author , Alvin MushlinAlvin Mushlin More articles by this author , Philip LiPhilip Li More articles by this author , and Richard K. LeeRichard K. Lee More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003297.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The World Health Organization (WHO) has recommended voluntary medical male circumcision (VMMC) as a prevention strategy for countries with low rates of circumcision and high rates of the heterosexually-transmitted human immunodeficiency virus (HIV). Early infant male circumcision (EIMC) is being considered due to its simplicity, rapid wound healing, and similar or more long-term benefits to adolescents and adults. However, data regarding the safety, efficacy, and cost of EIMC are limited. Thus, we sought to perform a comprehensive cost assessment of the ShangRing (SR) versus the standard of care (Mogen Clamp, MoC) as the EIMC device for future scale-up and a cost-effective HIV prevention strategy in this patient population. METHODS: As a secondary endpoint to an EIMC randomized controlled trial (RCT) of infants aged 0-60 days in Kenya, Tanzania , and Uganda, receiving SR versus MoC, utilization and cost data were analyzed. This included baseline facility costs, direct costs such as equipment, supply, and personnel costs, as well as indirect costs such as facility maintenance and capital cost for equipment. The Decision Makers Program Planning Tool (DMPPT) v1.0, developed by the USAID Health Policy Initiative in collaboration with UNAIDS, was utilized to perform a direct cost comparison of these two devices. This analysis tool derives a single unit cost of a procedure based on the baseline facility share, direct and indirect costs. All expenses adn costs related to this RCT are are reported in USD. RESULTS: A total of 1378 infant males underwent EIMC, of which 689 had SR , and 689 had MoC. No significant complications required additional cost or intervention at either study site. The overall cost of a single EIMC in Kenya, Uganda , and Tanzania were $61.30, $47.14 and $64.59, respectively for the SR ; and $56.38, $50.43, and $58.57, respectively, for the MoC. For both EIMC devices, the costs were mainly driven by direct costs. CONCLUSIONS: SR is a safe and low-cost alternative for EIMC in VMMC in Sub-Saharan Africa. Moreover, with scale-up utilizing lower-level personnel, the SR cost may be further reduced. Therefore, the SR is an attractive alternative for future EIMC initiatives in sub-Saharan Africa to further reduce the HIV burden in these regions. Source of Funding: The Bill and Melinda Gates Foundation © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e680 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mary O. Strasser More articles by this author Lina Posada More articles by this author Nahid Punjani More articles by this author Spyridon Basourakos More articles by this author Godfrey Kigozi More articles by this author Quentin Awori More articles by this author Alice Christensen More articles by this author Mark Barone More articles by this author Karla Ballman More articles by this author Marc Goldstein More articles by this author Alvin Mushlin More articles by this author Philip Li More articles by this author Richard K. Lee More articles by this author Expand All Advertisement PDF downloadLoading ...

Koszty programu małej retencji nizinnej i górskiej w RDLP Wrocław w latach 2008–2014

In the state forests managed by the State Forests National Forest Holding, the programmes aimed at increasing small water retention capacity have been implemented for many years. The forest districts from the Wrocław Regional Directorate of State Forests in 2008–2014 implemented lowland and mountain small retention programmes. The forest districts incurred costs of own contribution, covering 15% of investment costs as well as maintenance costs of small retention facilities for a period of 5 years after the completion of the investment. The paper presents the analysis of the costs incurred for the implementation of these programmes, with particular emphasis on the costs incurred for the maintenance of the realized small retention facilities. The total own share of the forest districts in the costs of programmes amounted to 38.3% in lowland areas and 31.3% in mountain areas.

Agrotourism Development Strategy in Wonogiri

This study aims to analyze and identify internal and external environmental factors, describe marketing strategies, and describe the priority strategies used by Soko Langit Agrotourism. The data processing and analysis method uses the IFE (Internal Factor Evaluation), EFE (External Factor Evaluation) matrix, the IE (Internal-External) matrix, the SWOT matrix (Strengths, Weaknesses, Opportunities, Threats), and QSPM (Quantitative Strategic Planning Matrix). The study results were obtained from five internal and five external factors, which resulted in eight alternative strategies in the marketing of Soko Langit Agrotourism. This study resulted in three strategic priorities related to visitor satisfaction, including a) improving the quality of facility maintenance; b) adding and maintaining rides in order to compete with competitors; and c) taking advantage of capital opportunities from the village government to reduce the number of loans from banks. Recommendations for strategies that can be implemented include: allocating capital opportunities from the village government for facility maintenance costs; adding rides with manageable maintenance levels; improving facilities that accommodate extreme weather changes; increasing the efficiency of financing from bank loans; and increasing the efficiency of facilities to accommodate extreme weather.

데이터 기반 지상용 변압기의 잔여수명과 고장확률(PoF) 도출방안 연구

In Korea, as power facilities are aging like overseas nations, maintenance and replacement costs of power facilities are expected to increase rapidly. In order to operate power facilities with a limited budget efficiently, it is necessary to introduce Asset Management System (AMS) in maintenance of the power facility in line with the global trend. To this end, it is essential for power companies to predict the remaining lifetime of power facilities and develop Probability of Failure (PoF) in their own way depending on the type and operating conditions of power facilities. Existing studies only calculated the statistical life expectancy of the power facility, but in this study, both of the statistical life expectancy and the condition remaining lifetime are presented in order to assess the PoF of power facility, in which the statistical life expectancy is calculated by using Weibull distributions. In this study, we present the criteria for determining the condition remaining lifetime using Health Index, inspection and diagnosis data of the pad mounted transformer operated by Korea Electric Power Corporation (KEPCO) in the field. In addition, the final remaining lifetime of the pad mounted transformer was derived through the folding function and was converted into PoF using Hazard rate distribution based on the apparent age. PoF derived in this study is expected to be used in the risk matrix of the AMS and useful in establishing the systematic maintenance plan of the pad mounted transformer.

Influence of Medium Voltage Distribution Line Configuration on Phase to Phase Sparkover Rate due to Direct Lightning Strike

In recent years, to reduce maintenance and management cost of distribution facilities, overhead ground wires are sometimes removed in a certain area. In such distribution lines, wire breaking at mid-span due to direct lightning is of concern. Although phase to phase sparkover is considered to be one of the factors of wire breaking at mid-span, its quantitative study has not yet been carried out. In this paper, at first, we experimentally examined detailed sparkover characteristics between phase conductors against short tail lightning impulse voltage, which is assumed to be phase to phase voltage. Next, based on experimental results, we estimate the phase to phase sparkover rate by means of lightning outage calculation program developed by CRIEPI. Estimated results suggest the phase to phase sparkover rate depends on the configuration of distribution lines, such as span length, arrangement of conductors, and so forth.

Chi phí phẫu thuật cắt amiđan tại bệnh viện Nhi Đồng 1 năm 2019

Objective: Determine full cost of tonsillectomy at Children’s Hospital 1 in 2019. Methods: Coss–sectional descriptive study 304 tonsillectomy children at Children’s Hospital 1 in 2019. Results: The study results showed that the cost of tonsillectomy (excluding consultation fees and pre-operation tests) depend on surgery devices. The average cost of cautery tonsillectomy was 1,740, 869 VND (68% direct cost, 32% indirect cost), of the coblator tonsillectomy was 3,610,031 VND 84.58% direct cost, 15.46% indirect cost), and of the plasma peak tonsillectomy one was 3,600,124 VND (84.54% direct cost, 15.46% indirect cost). In 3 surgery methods, the percentage’s cost of drugs, medical disposible items, and operation team were the largest share in direct costs; in indirect costs, the percentage of human management was the highest proportion, followed by the percentage of facility maintenance cost, and the percentage of other regular expenses cost was very low. Conclusion: The average cost of cautery tonsillectomy was 1,740, 869 VND, of the coblator tonsillectomy was 3,610,031 VND, and of the plasma peak tonsillectomy one was 3,600,124 VND.This cost is higher than the current hospital fee the patient or the health insurance paid. This implies a mismatch between input costs and hospital rates. Key words: Tonsillectomy cost, Children’s Hospital 1, cautery, Coblator, Plasma Peak Blade.

Pengadaan Awal Fasilitas Pemeliharaan dan Upaya Perolehan Filial 1 (F1) Ikan Zebra (Danio rerio) sebagai Hewan Laboratorium

Zebra fish (Danio rerio) is a laboratory animal that can be used for a wide field of research, testing, and education. Laboratories that wish to use Zebra Fish must have their own Zebra Fish rearing facility. The next step is to breed parental Zebra Fish from external sources until filial 1 (F1) is obtained in the facility which is then used later. This research is descriptive experimental, which describes the practical experience of providing maintenance, breeding, and rearing facilities for embryos and larvae. Quarantine specific facilities, number of tanks, water pH conditions, breeding methods, facility cleaning routines, and special larval feeds need to be considered for the success of early stage rearing facilities. This study showed that the embryo safety rate ranged from 38.2% to 88.9%. Meanwhile, for larvae up to the age of 21 dpf it ranged from 1.5%-9.1%, which indicated that the rearing conditions were still suboptimal, especially larval rearing. Facility procurement and maintenance costs are divided into mandatory and optional costs depending on the needs, location and time of the maintenance facility. Laboratories can independently design maintenance facilities that are effective to meet research needs and are cost efficient.

Modeling Deep Neural Networks to Learn Maintenance and Repair Costs of Educational Facilities

Educational facilities hold a higher degree of uncertainty in predicting maintenance and repair costs than other types of facilities. Moreover, achieving accurate and reliable maintenance and repair costs is essential, yet very little is known about a holistic approach to learning them by incorporating multi-contextual factors that affect maintenance and repair costs. This study fills this knowledge gap by modeling and validating deep neural networks to efficiently and accurately learn maintenance and repair costs, drawing on 1213 high-confidence data points. The developed model learns and generalizes claim payout records on the maintenance and repair costs from sets of facility asset information, geographic profiles, natural hazard records, and other causes of financial losses. The robustness of the developed model was tested and validated by measuring the root mean square error and mean absolute error values. This study attempted to propose an analytical modeling framework that can accurately learn various factors, significantly affecting the maintenance and repair costs of educational facilities. The proposed approach can contribute to the existing body of knowledge, serving as a reference for the facilities management of other functional types of facilities.

Development of Simulation for Predicting Maintenance Costs for Educational Facilities

In Korea, educational facilities are managed after issues are detected. Furthermore, due to imprecisely estimated maintenance costs, there are problems in managing educational facilities such as excessive budgets, etc. it is impossible to accurately estimate costs for various cases such as repairs and damages. Thus, the overall maintenance costs were analyzed based on probability of cases that may occur. This study proposes a system that predicts maintenance subjects and maintenance costs using probability values and that predicts the total maintenance cost through simulations. This study used simulations to accurately predict maintenance costs in various unexpected situations. The study was carried out by classifying into three categories according to each feature. The features were described according to the type of each item and simulation of the categorized items were produced separately to calculate the expected price. In the case of ‘annual fixed expenses’, the total of the maintenance cost tended to increase with a secondary curve where the slope gradually grows with time. In the case of ‘irregular expenses due to repairs/changes caused by minor failures’, maintenance cost had a certain cycle according to a failure rate according to the life of each item and an inflation rate of 1.9% was applied to show a tendency for occurrence to grow. In the case of ‘Replacement/repair costs according to the scheduled period for the entire educational facility’, the simulation results showed that each item had a constant cycle depending on the replacement period and that facility maintenance costs did occur. This study presumed data for simulations, but did not verify it. By supplementing such limitations, it will be possible to produce a reliable simulation model. The expected effect of reducing budget waste by predicting the exact cost of educational facilities through simulation.

Chemical Prevention and Control of the Green Tide and Fouling Organism Ulva: Key Chemicals, Mechanisms, and Applications

The green algae, Ulva spp., have been causing environmental problems worldwide, e.g., green tides and biofoulings. Green tides resulted from bloom floating Ulva have caused substantial economic losses. Ulva foulings increase the maintenance cost of marine facilities and contribute to the biomass of floating algae. Chemical methods are generally very inexpensive and convenient for suppression of Ulva spp. during their early life stages, thus solving the green tide and fouling problem at the source. In this paper, classical chemical methods that have been or are in use and emerging chemical methods under research are systematically reviewed. The advantages, disadvantages, mechanisms, and applications of these methods are also summarized. Highly toxic reagents are used in classical chemical methods, including oxidants, acids, heavy metal compounds, and synthetic biocides directly used or applied in antifouling coatings to kill or inhibit Ulva effectively. However, these toxic reagents have a high risk of resulting in secondary environmental problems. In order to minimize other environmental impacts while solving the current problem, emerging, and environmentally friendly chemical methods have been developed, such as the utilization of degradable natural products (mainly allelochemicals) and semi-natural products for Ulva inhibition and fouling control, and the use of flocculating agents to prevent microscopic propagules from germinating. All these chemical methods provide a promising direction for the prevention and control of Ulva.

Perceived Strategies for Financing Maintenance Cost of Physical Facilities in Secondary Schools, Imo State, Nigeria

This paper seeks to find out the strategies for financing maintenance cost of physical facilities in secondary schools in Imo state, Nigeria. Three research questions and two null hypotheses were formulated to guide the study. Survey research design was adopted. The population consisted of 475 principals in Imo state secondary schools in Nigeria. An instrument named Financing Maintenance Cost of Facilities Questionnaire (FMCFQ) was developed by the researcher. The FMCFQ was validated and its reliability coefficient was computed to be 0.85. Mean and standard deviations were used to analyze the research questions while t-test statistics was employed in testing the two hypotheses, Results show that principals accepted nine strategies out of fourteen for financing maintenance cost of facilities in secondary schools. While it is revealed that there is no significant difference between the perceptions of experienced and less experienced principals as well as those in urban and rural areas on the strategies for financing maintenance cost of facilities in secondary schools in Imo State. Some recommendations were made like the principals of schools should take it as a duty to maintain the school facilities with the help of ministry of education and the government for effective sustainability of nation development.

Artificial intelligence exploitation in facility management using deep learning

PurposeThis paper aims to apply a methodology that is capable to classify and localize mechanical, electrical and plumbing (MEP) elements to assist facility managers. Furthermore, it assists in decreasing the technical complexity and sophistication of different systems to the facility management (FM) team.Design/methodology/approachThis research exploits artificial intelligence (AI) in FM operations through proposing a new system that uses a deep learning pre-trained model for transfer learning. The model can identify new MEP elements through image classification with a deep convolutional neural network using a support vector machine (SVM) technique under supervised learning. Also, an expert system is developed and integrated with an Android application to the proposed system to identify the required maintenance for the identified elements. FM team can reach the identified assets with bluetooth tracker devices to perform the required maintenance.FindingsThe proposed system aids facility managers in their tasks and decreases the maintenance costs of facilities by maintaining, upgrading, operating assets cost-effectively using the proposed system.Research limitations/implicationsThe paper considers three fire protection systems for proactive maintenance, where other structural or architectural systems can also significantly affect the level of service and cost expensive repairs and maintenance. Also, the proposed system relies on different platforms that required to be consolidated for facility technicians and managers end-users. Therefore, the authors will consider these limitations and expand the study as a case study in future work.Originality/valueThis paper assists in a proactive manner to decrease the lack of knowledge of the required maintenance to MEP elements that leads to a lower life cycle cost. These MEP elements have a big share in the operation and maintenance costs of building facilities.

Optimization of biomass to bioenergy supply chain with tri-generation and district heating and cooling network systems

Bismil district of Diyarbakir (Turkey) is a region where agricultural activities are very common. About 60% of the terrain is irrigable. Cotton and corn are mostly grown in these irrigable lands. Given the bioenergy incentive provided by the Republic of Turkey and the extensiveness of agricultural lands in Turkey, energy production from cotton and corn residues in the tri-generation facility through gasification conversion technology seems like a quite profitable investment. In this study, a mixed-integer linear programming model, which optimizes the numbers, locations, and capacities of the tri-generation facility/s, was developed and empirically solved. The model tries to maximize the net present value of the potential investment by comparing the trade-offs between the raw material/end-product transportation costs, facility/s, and pipeline installation costs. Electricity and heating/cooling energy were sold to the government and settlements through the closest interconnected lines and pipelines, respectively. In this study, electricity, the heating/cooling energy and the fertilizer (biochar) sale were considered for the calculation of annual revenue, while transportation of raw materials and heating/cooling energy, losses during heat transfer and electricity transmission, operation and maintenance costs of facilities and pipelines were considered for the calculation of annual expenses. Initial investment cost includes facility, pipeline, and electricity transmission installation costs. The model proposes one facility with an installed power of approximately 35 MW which met cooling energy demand of 3 settlements, both cooling and heat energy demand of 2 settlements. The net present value of the investment is almost 338 million EUR and the repayment period is 1.3 years.

Assessment of factors affecting maintenance cost of public school facilities

PurposeThe purpose of this paper is to identify and assess the significance of various factors affecting maintenance costs of public school facilities.Design/methodology/approachDetailed literature review resulted in identifying 54 factors that were categorized under nine groups. This was followed by a questionnaire survey completed by 60 experienced professionals. The relative importance index was used to determine the in-group ranking, as well as the overall ranking of these factors.FindingsThe study established that the five most significant factors affecting the maintenance cost of public school facilities were “not providing operations and maintenance manuals to maintenance group” in the “construction phase” category, “ignoring maintainability studies in design” in the “design phase” category, “specification of low-quality materials” in the “design phase” category, “selection criteria of contractors” in the “regulations and contracting” category, and “lack of quality control during work execution” in the “construction phase” category.Originality/valueThe present research represents the first research covering the maintenance cost of public school facilities in Saudi Arabia. The study also presents the unique landscape of facility maintenance in the Saudi Arabian context. The outcome of this research has the potential to significantly cut down unnecessary costs rooted in expensive maintenance of public school facilities, enhancing the quality of these facilities. The findings also underscore the necessity of collaboration and coordination of the various key disciplines toward the realization of cost-effective school facilities.

Managing siloxanes in biogas-to-energy facilities: Economic comparison of pre- vs post-combustion practices

Siloxanes present in small concentrations in biogas interfere with the operation of biogas-to-energy facilities. During biogas combustion, siloxanes form white deposits on engine components (engine heads, spark plugs, valves) in crystals or amorphous forms depending on the temperature. The purpose of this study was to evaluate the economic feasibility of biogas-to-energy systems for managing the operational challenges due to siloxanes in biogas. The facility maintenance cost data were compiled by a survey of biogas-to-energy facilities in the United States. Economic analyses were performed to compare the operational costs due to increased maintenance for removing the white deposits forming on the engine components and the installation of a pretreatment system (carbon adsorption) to remove siloxanes prior to combustion. Numerical analyses showed that for the facilities with operating capacities less than 1300 m3/h (750 scfm), the costs for installation and operation of the carbon adsorption system exceeded the maintenance costs for removal of deposits from the engine components. The maintenance costs correlated well with the reported maintenance needs which were between 120 and 800 man hours per year. On the basis of siloxane removal costs alone, it is not economically feasible to install a carbon adsorption system for siloxane removal prior to combustion for small facilities processing less than 1300 m3/h (750 scfm) of biogas. However, using a process for siloxane removal prior to gas engines (e.g., carbon adsorption) would be improve the overall performance of the gas engines and reduce maintenance need at all facilities.

Optimal Sizing of PEV Fast Charging Stations With Markovian Demand Characterization

Fast charging stations are critical infrastructures to enable high penetration of plug-in electric vehicles (PEVs) into future distribution networks. They need to be carefully planned to meet charging demand as well as ensure economic benefits. Accurate estimation of PEV charging demand is the prerequisite of such planning, but a nontrivial task. This paper addresses the sizing (number of chargers and waiting spaces) problem of fast charging stations and presents an optimal planning solution based on an explicit temporal-state of charge characterization of PEV fast charging demand. The characteristics of PEV charging demand are derived through a vehicle travel behavior analysis using available statistics. The PEV dynamics in charging stations is modelled with a Markov chain and queuing theory. As a result, the optimal number of chargers and waiting spaces in fast charging stations can be jointly determined to maximize expected operator profits, considering profit of charging service, penalty of waiting and rejection, as well as maintenance cost of idle facilities. The proposed solution is validated through a case study with mathematical justifications and simulation results.