Unit Maintenance Research Articles

For the duration: Creating a collection maintenance unit in technical services

The University of Illinois-Chicago is an ARL member library with a collection of 2.3 million volumes. While we have access to many electronic resources, we still have a substantial collection of physical items to manage in several buildings. Many of those volumes are held at the Richard J. Daley Library on our east campus, where nonhealth-related academic programs are located. Late in 2015, the head of the Daley Circulation Department announced his retirement after more than 30 years in that position. The department was a typical academic library circulation unit, including circulation desk, shelving, reserves, and interlibrary loan. Most of the two dozen staff members had been with the department for many years.

PD VS HD in Post-Economic Crisis Greece—Differences in Patient Characteristics and Estimation of Therapy Cost

The aim of this study was to investigate patient characteristics and make an estimation of the cost of peritoneal dialysis (PD) and hemodialysis (HD) to Greek society during the economic crisis. We recorded the characteristics and the total cost of dialysis treatment in 100 patients on PD and 100 on HD. Total costs included dialysis procedure, consumables, drugs, laboratory tests, food, and transportation fees (only HD), covered by patients' insurance. Also included were medical and administrative salaries, purchase and maintenance of equipment and sanitary material, all covered by the state hospital. The mean patient age was 64.5 ± 16.8 years (PD) and 62.8 ± 15.1 (HD) (p < 0,001). The most common cause of end-stage renal disease (ESRD) was diabetes (32% for PD and 24% for HD patients). A total of 35% of the PD patients were employed vs 4% of the HD patients (p < 0,001). The mean distance from home for PD patients was 41.6 ± 17.3 km, while for HD patients, it was 9.4 ± 1.5 km (p < 0,001). Mean monthly cost for PD and HD treatment per patient was €4,019.20 ± 1,126.30 and €3,254.30 ± 37.50, respectively, both fully covered by patients' insurance. Mean monthly cost for PD or HD dialysis unit maintenance was €11,660.80 and €56,270.50, respectively, also fully covered by the state. There is likely to be a considerable difference in terms of total cost of PD vs HD therapy, owing to the fact that the operational cost of a PD unit appears to be significantly lower than that of a HD unit.

Generator maintenance scheduling based on the risk of power generating unit failure

A power utility’s ability to satisfy energy demand can be influenced significantly by unexpected breakdowns of power generating units. In most cases, such unexpected failures are also much more expensive to repair than taking planned preventative maintenance action. It has been found, especially in developing countries, that maintenance of often ageing power generating units is neglected due to high energy demand and low system capacity. The typical objectives pursued in the design of power generating unit maintenance schedules do not take these difficulties into account. A new scheduling criterion is therefore proposed in this paper. The occurrences of power generating unit failures may be estimated using methods from reliability theory in which the aim is typically to quantify the probability of a system completing its intended function for a specific duration of time. Based on this theory, our new scheduling objective seeks to maximise the probability of no power generating units in the power system failing during the scheduling window, weighted by the rated power generating capacity of each unit. The feasibility and effectiveness of this new objective is analysed by applying it, in conjunction with an exact solution approach, to two well-known generating maintenance scheduling test systems.

XV International Scientific and Engineering Conference Hermetic Sealing, Vibration Reliability and Ecological Safety of Pump and Compressor Machinery HERVICON+PUMPS-2017

September 5-8, 2017, Sumy State University, Sumy, UkrainePROCEEDINGS EDITED BYVolodymyr MARTSYNKOVSKYY, Prof., Dr., Dr.h.c., Sumy State UniversityIgor TVERDOKHLEB, Ass. prof., Dr.-Ing., HMS GROUPAndriy ZAHORULKO, Ass. prof., Dr.-Ing., Sumy State UniversitySerhii HUDKOV, Dr.-Ing., Sumy State UniversitySelected, peer reviewed papers from the XV International Scientific and Engineering Conference HERVICON+PUMPS-2017FOREWORDThe Conference Proceedings devoted to problems of reliability and economy of pump and compressor equipment are offered to the attention of specialists. The book presents 58 papers of various authors, included in the Program of the XV International Scientific and Engineering Conference HERVICON+PUMPS-2017, which, since 1976, with an enviable constancy passes every three years in Sumy on the basis of the General Mechanics and Machine Dynamics Department of the Sumy State University. The main sponsor that provided holding of the current conference, as well as the previous one, was the HMS Group, demonstrating an effective interest in the technical progress development.Published papers are grouped in five sections, which cover a wide range of issues of modern theory and practice of centrifugal machines. At the present stage of its development, the theory, thanks to the successes of computational mathematics and computer technology, is experiencing a period of prosperity. The possibility of numerical analysis of more perfect mathematical models of unsteady flows of real liquids and gases in flow channels has appeared. The existing solutions are specifying, the new physical processes laws accompanying the operation of pumps and compressors are finding. In the published papers, at least to a small extent, the present state of the theory of these machines is reflected. Part of the papers is devoted to the implementation of new design solutions. The results of experimental investigations and operational experience of the proposed designs are given (Sections 1 and 2).Centrifugal pumps and compressors - rotary machines. The most critical units of these machines are bearings and seals, which are complex tribomechanical systems. The papers given in Section 3 and 4 are devoted to the problems of calculating and designing of bearing and seals, increasing of the wear resistance of friction pairs.The unbalanced rotor of a centrifugal machine is the source of vibration disturbances, which determine the vibration state of the machine as a whole. At the same time, the level of vibration is one of the main indicators of reliability, therefore reliability problems are directly related to the rotor dynamics in the bearings and annular seals. The rotor dynamics are discussed in Section 5.On behalf of the authors’ team, I hope that the papers published in the book will awaken the interest of young research engineers and will be useful to experienced designers in creating new reliable and economical pumps and compressors. In addition, the technical personnel involved in the maintenance and repair of units, can to get useful information from the book.Professor Volodymyr A. MartsynkovskyyList of Scientific Committees and Chair members are available in this pdf.

Serving Too Many Masters: Multiple Managers and Worker Performance

Project-based work has been going through fundamental transformations in the last decades, with the emergence of fluid teams that are frequently created to accomplish short-term tasks. This new matrixed form of organization requires workers to report to multiple managers simultaneously. Contrary to the prevalent view in the literature, we argue that there is an inverted U-shaped curvilinear relationship between the number of managers and worker performance. We also argue that the costs outweigh the benefits much sooner in the presence of complex tasks and a higher proportion of managers collocated with the worker. Using timesheet data from the software maintenance unit of a multinational, Fortune 500 IT company organized in fluid project teams we empirically explore our arguments and find evidence for our hypotheses.

Development of the Reconnected Metro Train Control and Monitoring System

Train Control and Monitoring System (TCMS) is usually used to monitor the status of train and all the subsystem, to control the train-level functions and vehicle-level functions, including the control of the Propulsion Subsystem, the Braking Subsystem, the Passenger Information Subsystem, and so on. This paper mainly introduces the design of metro train control and monitoring system, including the designs of network structure, Vehicle Control Unit (VCU), Human Machine Interface (HMI) and Portable Maintenance Unit (PTU), and summarizes the advantages of the new network system.

Contributions of Transports Engineering to the Organization and Functioning of the Mobile Emergency Service/ Brazil

Background The present case study had as object of investigation the Mobile Emergency Service, in the Brazilian context, from the approaches of Transport Health and Engineering. The Mobile Emergency Service was introduced in Brazil in 1996 inspired by the French model. In addition to ambulances, services are provided by motorcycles and even bicycles. The last one offered only in one of the units of the federation in less serious situation. It is inserted in the Unified Health System, which guides Brazilian public health. It should be pointed out that in order to understand the object of the study, an initial approximation was sought with the guidelines that guide the Brazilian health system due to its peculiarities. Objective of the study is to analyze the organization and operation of Mobile Emergency Service, seeking to identify the possibilities of contributions of Transport Engineering for the optimization of said service. Methods The study was based on documentary research from secondary sources in the form of institutional documents offered on official sites or made available for the study. Results The potential of Transport Engineering's contribution was identified in the form of a proposal to estimate the useful life of the vehicular units that enable the operation of the Mobile Emergency Service. Considering the endogenous and exogenous elements to the Mobile Emergency Service, four important axes are identified in the determination of the useful life of vehicular units. Health: indicators and social determinants of health, management and working conditions of drivers of vehicular units; Transport: elements pertinent to the geoprocessing and maintenance of vehicular units; Legislation: Unified Health System guidelines; Socio-economic-profiles and sanitary and epidemiological reality of the population. Conclusions The use of different approaches and techniques is necessary to determine the useful life of a vehicle that makes up the Mobile Emergency Service infrastructure. The contribution of this study is to signal the potentialities of a model to measure the useful life of vehicular units from the contributions of two areas of knowledge in an integrated way. It is intended in the future the application of the proposal and the verification of its results considering the optimization of said services and public resources.

Cost Effective Integrated Maintenance Scheduling in Power Systems using Ant Lion Optimizer

Integrated system preventive maintenance is an exigent job in both regulated as well as deregulated utility systems that must be carried over by the utilities in order to extend their continuation and performance. The generator maintenance scheduling is commonly focused, but the line flow limits in the transmission lines, which are connected to the generating units may violate due to the outages. Thus, maintenance planning of generators and transmission lines has become indispensable and the Integrated Maintenance Scheduling (IMS) addresses alike. Inclusion of transmission lines and line flow constraints in generating unit maintenance will increase intricacy of the problem that enforces IMS for secure and economic operations. As an efficient optimization tool is necessary, the modern bio inspired algorithm, Ant Lion Optimizer (ALO) has been intended for the first time to address the IMS problem. The well-known / standard test systems are used for demonstration and the attained numerical results by simulation are compared with other meta-heuristic methods. The comparison reveals that the ALO is a positive choice for solving IMS problems.

Water Wave Optimization Algorithm for solving Thermal Unit Maintenance Scheduling

Water Wave Optimization Algorithm for solving Thermal Unit Maintenance Scheduling

Innovative Maintenance Model: Methodology of Decision Making and Global Economic Cost – Based Choice Using Fuzzy Logic Concepts

Background:In this paper, we propose the Development of a knowledge-based expert system applied to Electricity distribution Network maintenance.Method:The expert system utilizes the Matlab®platform, using its proprietary Fuzzy Logic Toolbox. The inputs to the expert system are the different situations related to cost variables to and the implementation of one of the maintenance optimizing solutions pertaining to the Live Work-Redundancy-Simultaneity-Security model as defined by the maintenance unit during a the global life cycle of the equipment. The output of the system indicates the economic feasibility and benefit of the solution to be adopted of for our Maintenance model. Application of the expert system methodology is shown as a simulation.Conclusion:The expert system may be of valuable assistance to utility engineers or asset managers in making strategic maintenance decisions such as “Economic solution”.

Optimal track utilization in electric multiple unit maintenance depots

The Chinese high-speed rail network has a fast-growing number of electric multiple units (EMU) in service and is facing increasing pressure of maintaining all EMUs on-time. The capacity at an EMU maintenance depot is relevant to its track utilization rate, which can be improved by a better EMU-to-track assignment in various areas, such as the maintenance yard, temporary storage yard, and washing yard. Most tracks at EMU depots have two sections that can accommodate one long EMU of sixteen railcars or two short EMUs of eight railcars. The two yard types, stub-end and through, further add complexity to the assignment problem, which is currently handled manually. To make the assignment process more efficient, this paper proposes a simple optimization model for yards with either type and with any combination of long and short EMUs. The numerical results based on a real-world case show that the proposed solution method can yield an assignment plan with the optimal track utilization in a small amount of computational time and can be implemented in a computer-aided planning system easily. The case also discusses potential changes in practice to improve the track utilization rate, such as changing the maintenance schedule and connecting two short EMUs into a long EMU. After comparing the track utilization rates between the two yard types, the paper suggests that the through type is more appropriate for the current schedule at EMU depots, especially for the maintenance yard.

A Branch-and-Price algorithm for railway rolling stock rescheduling

How to best reschedule their fleet of rolling stock units during a disruption is an optimization problem regularly faced by railway operators. Despite the problem’s high complexity, it is still usually solved manually. In this paper we propose a path based mathematical formulation and solve it using a Branch-and-Price algorithm. We demonstrate that, unlike flow based approaches, our formulation is more easily extended to handle certain families of constraints, such as train unit maintenance restrictions. The proposed algorithm is benchmarked on several real-life instances provided by the suburban railway operator in Copenhagen, DSB S-tog. When used in combination with a lower bound method taken from the literature we show that near-optimal solutions to this rescheduling problem can be found within a few seconds. Furthermore, we show that the proposed methodology can be used, with minor modification, on a tactical planning level, where it produces near-optimal rolling stock schedules in minutes of CPU time.

The Monitoring System of an Actual Technical Condition for Pumping Units with Frequency Analysis

Maintenance and repair of pumping units requires a lot of high material costs and time. Planned maintenance is usually used now. But in inter-maintenance period nobody knows real technical condition of units. Automated control system of vibration parameters in real time is presented. It show actual state of a pump at every time moment. Developed by the authors diagnostic system includes a complex diagnosis of the spectral characteristics of the unit and trend analysis change of the vibration characteristics in real time. Comparison of current vibration spectrum with typical vibration spectrum of defects allow to identify a defect with a certain probability. Therefore, control of vibration and parametric characteristics of pumping units in real time allows to identify defect of pumping units at an early stage.

Transformer Fleet Monitoring

Transformer monitoring systems are increasing in number and having a clear overview of the whole fleet of monitored transformers is becoming crucial in an effort to provide the end user with an easy way to monitor its transformer assets and react accordingly to the monitored situations. This paper will introduce a Fleet monitoring solution that provides the architecture and tools to accomplish the set tasks of connecting and accessing information of all the monitoring systems from their dedicated locations.Standard transformer monitoring system configuration is made of a local unit on the transformer for collecting and processing raw data from the sensors and transferring the data to another unit, usually a server located in the substation which stores it in the database. The server unit is also responsible for the presentation of data to the end user and communication with supervisory control systems. This configuration is well capable of achieving its purpose of monitoring the transformer state and operation. The challenge is in accessing the monitored data.Traditional approach for accessing the data was to access the servers locally in the substations. Responding to the monitored conditions was done by connecting critical alarm signals from the monitoring system to the substation control system and in case of an alarm indication the operator from the substation was required to access the monitoring system for further details and inform personnel responsible for the maintenance of transformer units. The transformer maintenance personnel were then required to check the monitored data either by connecting remotely to the monitoring system, which in most cases is not possible due to security and technical restrictions, or to travel to the remote location to investigate the issue. This approach was both very time consuming and costly. There is also a consideration that the modern substations are becoming unmanned or have just a basic crew which may consist of personnel not qualified or trained for the required tasks.The challenge was to enable a centralized access to the distributed monitoring systems across multiple substations. An architecture, both hardware and software, was developed, that accomplishes this task. The architecture is highly modular so that the components of the system can be distributed and integrated into an overall system which is fully customizable to the end user requirements. During development one of the main considerations was to make the integration of already existing systems as seamless as possible. The result is a Fleet monitoring solution that centralizes access to the information from all connected monitoring systems while at the same time does not interfere with the work of dedicated monitoring systems at remote locations. This way the data can be presented directly to the right personnel. This paper will also discuss further goals and directions of development for transformer fleet monitoring.

Potential and innovative development prospects of Russia’s nuclear industry export

There are considered the key milestones in the development of the Russian nuclear power: the fi rst studies of nuclear physics (the 1920s – 1930s); implementation of the «atomic project» (the 1940s); large-scale development of civil nuclear energy (the 1950s – 1980s); a crisis and restoration of nuclear industry (1990 – 2007); active development on the global nuclear energy market (2007 – present). Analysis is provided of the current state and development prospects in all the key segments of the nuclear industry in Russia: uranium mining, uranium conversion, uranium enrichment, nuclear fuel fabrication, construction of nuclear power plants (NPPs), nuclear power engineering, operation of NPPs and power production, maintenance of NPP power units, decommissioning of NPPs, handling radioactive waste and spent nuclear fuel. Russia is identifi ed as one of the global leaders in all these segments of the world nuclear market (having, among other things, the world’s largest portfolio of NPP orders and the largest uranium enrichment capacities). The export potential for each of the nuclear industry segments under consideration is identifi ed and assessed. It is shown that the segments of NPP construction and manufacturing of nuclear power equipment production are of the largest export potential for Russia. At an early stage of the nuclear fuel cycle, the segment of enriched uranium product and nuclear fuel fabrication has the greatest prospects for growth in export supplies due to the growing number of NPP units of Russian design in the world and Russia’s entry to the market of fuel fabrication for reactors of foreign design.

Geographical features of forest vegetation reflected at the level of the lower-rank syntaxa (evidence from the Russian part of the Upper Dnieper basin)

Phytogeographical features of forest vegetation at the level of lower-rank syntaxa were being discussed in literature since the early 20th century (Cajander, 1903; Sukachev, 1926; Braun-Blanquet, 1964; Kral et al., 1975; Kleopov, 1990; Bulokhov, 2003; Ellenberg, 2009), however, phytocoenologists still have no uniform interpretation and geographical maintenance of lower classification units. Forest vegetation of the European part of Russia is well studied according to Braun-Blanquet approach with association as a system of geographical subassociations. The paper offers the approaches to the reflection of geographical variations of the natural forest vegetation in the basin of the Upper Dnieper (central part of the East European Plain) at the level of lower-rank syntaxa The xeromesophytic oak woods in the basin of the Upper Dnieper belong to the East European ass. Lathyro nigri–Quercetum roboris Bulokhov et Solomeshch 2003. Floristic differentiation of this association from the similar Central European ass. Potentillo-Quercetum is given. These two associations have large blocks of geographically significant differential species that does not allow to consider them as a part of one association. The suggested approach allows to define the chorological content of units of lower syntaxonomical ranks and make regional classification schemes comparable to each other.

A 0/1 mixed integer linear programming approach to establish an effective preventive maintenance policy for power plant

Most generating unit maintenance scheduling packages consider the preventive maintenance schedule of generating units over a one or two year operational planning period in order to minimise the total operating cost while satisfying system energy requirements and maintenance constraints. This problem consists of ascertaining which generating units must be halt production. The generating unit is to be examined regularly for safety. It is very important because a failure in a power station may cause a general breakdown in an electric network. The main consequence is that the electricity demand of customers will not be satisfied in such cases. Therefore, reliability is the key point used in the methodology presented. The problem is approached as an optimisation issue. The model is developed by determining the objective function which is the net unit power reserve. Some constraints are used to obtain desired output.0/1 mixed integer linear programming is used to solve the model reached. A practical approach is carried out by implementing the model in a power plant. The result obtained is a schedule that allows the efficient organisation of preventive maintenance over a specific time.

Factors Causing Acinetobacter Baumannii Resistance to Carbapenem Antibiotics in Patients with Healthcare Associated Infection (HCAI) at Dr. Moewardi Hospital, Surakarta

Background: Acinetobacterbaumannii is a negative gram opportunistic bacteriumhaving high survival ability in the environment. Carbapenem is a drug of choice for infections caused by Acinetobacterbaumannii , which in the last decade prevalence of Carbapenem Resistant Acinetobacterbaumannii (CRAB) has increased. CRAB is commonly found in a nosocomial infection case and even into disease outbreak and epidemics in various hospitals. However, CRAB in community-associated infection data is still limited primarily in Indonesia. Therefore the researchers intend to do study factors causing CRAB in hospital and community setting in patients with Healthcare Associated Infection (HCAI). Subjects and Method: This study was an observational analytic study, with case control design. The study was conducted in RS Dr. Moewardi Surakarta in March-August 2017. Taking subject used fixed disease sampling method with the number of samples were 104 subjects. The dependent variable was the incidence of Acinetobacterbaumannii resistance to carbapenem antibiotics in HCAI patients. Independent variables were history of antibiotic use, patient functional status, intensive unit maintenance and comorbid conditions. Dependent and independent variables were measured by using a questionnaire checklist and then analyzed by using multiple logistic regression analysis. Result s : Previous antibiotic conformity history (OR = 0.12; 95% CI = 0.03 to 0.45; p = 0.002) and the patient functional status (OR = 6.72; 95% CI = 2.08 to 21.68; p = 0.001) increased risk of resistance of Acinetobacterbaumannii to carbapenem (CRAB) in Healthcare-Associated Infections (HCAI) patients and was statistically significant. Treatment at intensive unit (OR = 0.76; 95% CI = 0.26 to 2.23; p = 0.613) and comorbid conditions (OR = 0.38; 95% CI = 0.12 to 1.23; p = 0.106) increased risk of Acinetobacterbaumannii resistance to carbapenem (CRAB) in Healthcare Associated Infections (HCAI) patients although it was statistically insignificant. Conclusion: Previous antibiotic conformity history and functional status of patients are a factor affecting Acinetobacterbaumannii resistance to carbapenem (CRAB) in Healthcare-Associated Infections (HCAI) patients. Keyword: Acinetobacterbaumannii , carbapenem, healthcare associated infection. Correspondence : Widana Primaningtyas. Master Program in Public Health, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta 57126, Central Java. Email: widanadoctor@gmail.com Mobile: +6285229035800. Indonesian Journal of Medicine (2017), 2(2): 125-138 https://doi.org/10.26911/theijmed.2017.02.02.07

The Effects of Sentence Repetition-Based Working Memory Treatment on Sentence Comprehension Abilities in Individuals With Aphasia.

This study investigated whether sentence repetition-based working-memory (SR-WM) treatment increased sentence-repetition abilities and the treatment effects generalized to sentence-comprehension abilities, WM-span tasks, and general language-assessment tasks. Six individuals with aphasia participated in the study. The treatment consisted of 12 sessions of approximately 1 hr per day, 3 times per week. The SR-WM treatment protocol followed components including maintenance and computation of linguistic units by facilitating a chunking strategy. We manipulated the length and syntactic structures of the sentence-repetition stimuli using a limited set of vocabulary. Participants demonstrated significant increased repetition ability in treated and untreated sentences after treatment. Furthermore, they showed generalization effects on the sentence-comprehension task, WM measures, and general language tasks, but with some differential patterns, depending on task demands. The SR-WM treatment approach, by manipulating syntactic structures and minimizing top-down semantic processing, elicited increased performance on sentence repetition as well as other linguistic domains. Results indicated that it is clinically and theoretically important to examine whether WM treatment serves as a potentially underlying treatment approach that facilitates the distributed network associated with language processing.

Management of interruptions to fractionated radiotherapy treatments: Four and a half years of experience

Background and purposeThe study objective was to report our four-and-a half years experience (March 1 2011–August 15 2015) of a program to manage interruptions in fractionated radiotherapy treatments. MethodsA program was developed, based on a specific database, to manage treatment interruptions. Benefits of the program were analyzed in reference to previously published data. Analysis was also performed of two measures to reduce OTT prolongation and improve treatment outcomes: working on public holidays and conducting treatment unit maintenance on Saturdays. ResultsThe study included 2352 patients. Patients with head and neck cancer obtained the greatest benefit from the program, with a mean increase in TCP of 3.5% and a benefit of at least 4% in 45.6% of them. In prostate cancer patients, the likelihood of biochemical failure was reduced by a mean of 2.0% and was reduced by at least 4% in 19.7% of them. Application of the two proposed measures would have improved the TCP by a mean of 5.4% in head and neck cancer patients. The impact of the compensations program and proposed measures is lesser in the remaining cancer types studied. ConclusionsImplementation of a compensation program has a significant impact on patients with head and neck or prostate cancer but OTT prolongation remains excessive in many treatments. The introduction of fractions on public holidays would assist in the meeting of recommendations for these patients.