Maintenance Manpower Research Articles

PET without cyclotron

Positron emission tomography (PET) has been well established noninvasive imaging technique for diagnosis, staging/ restaging and monitoring of therapy response in oncology. Molecular imaging using positron emitting radionuclides kinetics provides quantitative in vivo assessment of biological and physiological processes involved in the earlier stages of disease progression. Because of the short life time (hours) of many of the PET radioisotopes, a cyclotron and radiocompound synthesis facility is required. One of the most widely recognized advantages of PET is the use of the positron emitting biologic radiotracers, e.g., C (T = 20 min), N (T = 10 min), O (T = 2 min), and most important F (T = 110 min) that mimic natural substrate. However, due to relatively short half-lives, they are unable to be transported to sites at great distances from the production facility. The production of radioisotopes using a cyclotron/accelerator demands a knowledge of excitation functions (reaction cross section), development of high current targets, radiochemical separations at no-carrier added level, recovery of enriched target materials in most of the cases, remote control and highly trained manpower for running, repair and maintenance. Cyclotrons are generally used for production of short-lived radioisotopes; however, long-lived isotopes are also produced which can be used at distant places. Fast and high resolution imaging method, such as single photon emission computed tomography (SPECT) is now commonly available for diagnostic studies in developing countries, whereas PET facility is rarely employed for patient management due to non-availability of cyclotron in these countries. Positron emission tomography has two major advantages over SPECT, namely, better spatial resolution and greater sensitivity. The number of positron emitting radionuclides is large. However, most of the PET studies are performed near to cyclotron production facility with short-lived positron emitters (C, O, N, and F). A tabulation of 157 positron emitting radionuclides which have the physical characteristics deemed appropriate for radiopharmaceutical use is provided by Lambrecht [1]. Some cyclotron produced generator radionuclides have also been listed by Qaim [2]. Table 1 presents the generator produced positron emitters, which can be utilized far from production site for PET studies. Production route of parent in a cyclotron and separation of daughter is discussed elsewhere [3]. Antibody-PET imaging might be of value for the selection of radioimmunotherapy (RIT) candidates to confirm tumor targeting and to estimate radiation doses to tumor and normal tissues. One of the requirements to be set for such a scouting procedure is that the biodistributions of the diagnostic and therapeutic radioimmunoconjugates should be similar. The potential of the positron emitters zirconium-89 (Zr) and iodine-124 (I) for this approach, as these radionuclides have a relatively long half-life that matches with the kinetics of MAbs in vivo (T1/2 3.27 and 4.18 days, respectively), were evaluated [4]. Other long-lived positron emitters, which may be used at distant places are, V (T = 16 d), Mn (T = 5.59 days), As (T = 17.78 days), and Au (T = 39.5 h). Through the supply of a long-lived parent radionuclide, from which a short-lived daughter radionuclide can be milked off periodically at hospitals, it has become possible A. Mushtaq (&) Isotope Production Division, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad, Pakistan e-mail: mushtaqa@pinstech.org.pk

Optimising aircraft wash intervals from maintenance records

Washing aircraft is a routine maintenance chore that is intended to reduce corrosion damage by removing corrodents. However, this exercise incurs costs that are substantial when applied to a fleet. The United States Air Force (USAF) algorithm for setting wash intervals was based on an environmental severity index and an implied set of economic assumptions. A novel approach is described for setting the economically optimal wash interval based on maintenance records, an atmospheric corrosion model, explicit economic parameters and corrosivity measurements. The maintenance records required are the number of man hours applied to repairing corrosion related damage and the number of months since the last repair. The atmospheric corrosion model assumed a bilogarithmic or power law relationship between cumulative damage and exposure time. The economic parameters considered are the cost per wash, the cost of unavailability during a wash and the charge rate for maintenance manpower. It is assumed that atmospheric severity increases corrosion damage, whereas washing decreases it. This approach requires a measure of atmospheric corrosivity that is not restricted to any particular method as long as the processing of maintenance data and the prediction of the optimal wash interval uses the same method.

Manpower Management Benefits Predictor Method for Aircraft Two Level Maintenance Concept

In maintenance management process of aircraft, how to use the lesser maintenance manpower to get in return the higher maintenance Benefits, it is a problem that the management specialists pay more attention to, so, manpower management and cost estimate are the important compose parts of aircraft Life Cycle Costs (LCC) management. Via improve the maintenance level of aircraft, predigesting maintenance system from three level to two level maintenance (TLM) could save manpower, improve readiness, achieve the goal of bring favorable maintenance management Benefits. We imported gray system Verhulst model theory, established the manpower management forecast model for transforming maintenance system, and predicted according to the actual save manpower data of the United State Air Force. It is proved that the creditability of the prediction model is higher, has certain practical value.

Digitale Foto- und Videoarchivierung in der HNO

Digital media have become standard documentation tools in modern ENT clinics. To date, multiple formats are generated by variable data sources. Old fashioned archiving techniques with numerous print-outs, hard copies or even slides would soon generate an unmanageable data flood and require costly manpower for proper and precise maintenance. It has become obvious that data archiving is the prime challenge for modern hospital information technology. Multiple computerized multimedia archives exist and offer promising solutions for collecting and managing these data. From a clinical point of view, not only data centralisation but also interactions with existing network components and hospital information technology systems have to be made available. Here, we describe variable data sources and formats, centralisation techniques, networking options and discuss available digital documentation solutions.

Construction management of Indian pressurized heavy water reactors

Pandit Jawaharlal Nehru and Dr. Homi J. Bhabha, the visionary architects of Science and Technology of modern India foresaw the imperative need to establish a firm base for indigenous research and development in the field of nuclear electricity generation. The initial phase has primarily focused on the technology development in a systematic and structured manner, which has resulted in establishment of strong engineering, manufacturing and construction base. The nuclear power program started with the setting up of two units of boiling light water type reactors in 1969 for speedy establishment of nuclear technology, safety culture, and development of operation and maintenance manpower. The main aim at that stage was to demonstrate (to ourselves, and indeed to the rest of the world) that India, inspite of being a developing country, with limited industrial infrastructure and low capacity power grids, could successfully assimilate the high technology involved in the safe and economical operation of nuclear power reactors. The selection of a BWR was in contrast to the pressurized heavy water reactors (PHWR), which was identified as the flagship for the first stage of India's nuclear power program. The long-term program in three stages utilizes large reserves of thorium in the monazite sands of Kerala beaches in the third stage with first stage comprising of series of PHWR type plants with a base of 10,000 MW. India has at present 14 reactors in operation 12 of these being of PHWR type. The performance of operating units of 2720 MW has improved significantly with an overall capacity factor of about 90% in recent times. The construction work on eight reactor units with installed capacity of 3960 MW (two PHWRs of 540 MW each, four PHWRs of 220 MW each and two VVERs of 1000 MW each) is proceeding on a rapid pace with project schedules of less than 5 years from first pour of concrete. This is being achieved through advanced construction technology and management. Present efforts are focused on further reduction of gestation period. This is in contrast to construction period of 7–14 years in the earlier projects with labour intensive construction methods, learning period and indigenisation. The schedule and cost are interrelated and ultimately determine the viability and competitive edge of a project. With rich experience of over 30 years of operation and construction management it is well established that setting up of nuclear power projects in India in 4–5 years is quite feasible because of tremendous developments in construction technology; mechanization, parallel civil works and equipment erection, computerized project monitoring and accounting systems. By considering the best achieved times for the critical path activities of previous and ongoing projects, even a 4-year schedule is achievable. For nuclear power to be competitive it is essential that the gestation period is reduced and the capacity utilization enhanced. Both of these are the goals of the Indian nuclear power program. Presently the overnight cost per kW installed capacity is in the range of US$ 1100–1300 with levellised tariff of 5 c/kWh.

Optimal Reactive Power Dispatch Considering Costs of Adjusting the Control Devices

The traditional model of optimal reactive power dispatch (ORPD) for power systems is based on the principle of income maximization, which aims at minimizing active power loss of the whole networks. However, such a model may bring on excessive operations of device-control devices in real-time application. To realize reactive power dispatch, power utilities should increase equipment investment and added manpower for operation and maintenance. On the other hand, the operations would augment the fault probability of power systems. Therefore, the costs of adjusting the control devices (CACDs) are investigated, and a novel mathematical model of ORPD is presented in this paper, whose objective function is to minimize the energy loss at the current time interval and the CACD. A simulation test is presented to demonstrate that the proposed model reflects the principle of profit maximization and describes the ORPD problem with time-varying loads appropriately since it can decrease active power loss and avoid excessive controls simultaneously.

Physico-chemical Treatment of Wastewater From Clusters of Small Scale Cotton Textile Units

Small scale industries can not own individual wastewater treatment facility due to non-availability of land and skilled manpower for operation and maintenance of wastewater treatment plants. A centralized wastewater treatment facility for clusters of small scale industries is appropriate. This concept is gaining popularity in recent years. In India, various textile process operations are undertaken by individual small scale units. The wastewater generated at these units is conveyed to a common effluent treatment facility comprising of equalization, flocculation-clarification, activated sludge process, secondary clarification and finally discharge into inland surface water bodies. The wastewater from small scale cotton textile processing units was highly coloured and alkaline with average BOD and COD concentration of 205 and 790 mgl−1, respectively. Due to the presence of several dyes, particularly reactive dyes, the biological treatment is often found less effective. Therefore, applicability of various physico-chemical treatment methods needs to be investigated in pursuit of an alternative to biological treatment of textile wastewater. A physico-chemical treatment scheme, involving chemical coagulation-sedimentation, dual media filtration, activated carbon adsorption followed by chemical oxidation was investigated in this paper. The quality of final treated wastewater in terms of BOD and COD was 18-24 and 230-240 mgl−1, respectively through this scheme. A scheme of treatment comprising coagulation-sedimentation, dual media filtration, activated carbon, chemical oxidation may be considered as an alternative to biological treatment of textile wastewater.

Airline short-term maintenance manpower supply planning

It is essential that airlines efficiently perform aircraft maintenance in order to ensure aviation safety and schedule punctuality. Traditionally, the arrangement of the maintenance manpower supply has been based on staff experience, and has been performed manually following simple rules. This is not only time-consuming but often ineffective. In this research we consider technicians with multiple types of aircraft maintenance certificates incorporated with three flexible management strategies and the related operating constraints to develop a mathematical programming model. With suitable modifications, eight different flexible strategic models, associated with different strategy combinations, can be generated to help an airline effectively manage its maintenance manpower supply. The models are formulated as mixed integer programs. Because the problem sizes of the proposed models are expected to be huge in real applications, we have developed a solution algorithm to efficiently solve the problems. We employed the mathematical programming solver, CPLEX, to reach a solution for all the problems. Finally, to evaluate the models and solution algorithm developed in the research, we performed a case study using the operating data from a leading Taiwan airline. The preliminary results indicate that the proposed models, and the solution algorithm, are both efficient and effective.

A model and a solution algorithm for airline line maintenance manpower supply planning with multiple aircraft type maintenance certificates

Traditionally, aircraft maintenance manpower supply planning in Taiwan is based on staff experience, which is neither efficient nor effective. In this research, we developed a model to help airlines to efficiently and effectively plan their maintenance manpower supplies to deal with multiple aircraft type maintenance certifications. The model is formulated as a mixed integer program which is characterized as NP‐hard. Because the problem size of the proposed model was expected to be huge, we developed a heuristic algorithm to solve the problem. To evaluate the model and the solution algorithm, we performed a case study using the operating data from a Taiwan airline. The preliminary results indicate that the proposed model and the solution algorithm are both efficient and effective.

An airline maintenance manpower planning model with flexible strategies

An effective maintenance manpower supply plan not only reduces operating costs but ensures greater aviation safety and punctuality. A variety of flexible management strategies have been widely applied in other industries; however, little research has stressed flexible management strategies for airline crew scheduling problems. Here, we introduce a model that includes various flexible strategies so that an airline can effectively manage its maintenance manpower supply. The model is formulated as a mixed integer program that is solved using a commercial software package, CPLEX. In order to evaluate the model performance, we use the operating data from a leading Taiwan airline.

New large solar photocatalytic plant: set-up and preliminary results

A European industrial consortium called SOLARDETOX has been created as the result of an EC-DGXII BRITE-EURAM-III-financed project on solar photocatalytic detoxification of water. The project objective was to develop a simple, efficient and commercially competitive water-treatment technology, based on compound parabolic collectors (CPCs) solar collectors and TiO 2 photocatalysis, to make possible easy design and installation. The design, set-up and preliminary results of the main project deliverable, the first European industrial solar detoxification treatment plant, is presented. This plant has been designed for the batch treatment of 2 m 3 of water with a 100 m 2 collector-aperture area and aqueous aerated suspensions of polycrystalline TiO 2 irradiated by sunlight. Fully automatic control reduces operation and maintenance manpower. Plant behaviour has been compared (using dichloroacetic acid and cyanide at 50 mg l −1 initial concentration as model compounds) with the small CPC pilot plants installed at the Plataforma Solar de Almerı́a several years ago. The first results with high-content cyanide (1 g l −1 ) waste water are presented and plant treatment capacity is calculated.

Renewable energy education in Botswana: needs, status and proposed training programs

Lack of trained manpower for repair and maintenance of solar energy devices in Botswana has resulted in failure of devices, loss of revenue, and dwindling of consumer faith in solar technologies. The government of Botswana commissioned a study to assess the needs for trained manpower in New and Renewable Sources of Energy (NRSE) technologies, to identify the required training programs and their levels, and the facilities that need to be upgraded and/or created for the implementation of such training programs at the existing technical and educational institutions within the country. The paper presents the findings of the study, and the recommendations made. The study proposed seven training programs at progressively increasing skills and expertise levels that include two certificate courses in each of the solar water heating and photovoltaic technologies for maintenance personnel, a national craft certificate program in solar energy technologies, a higher diploma in energy technologies for supervisory personnel, and a short course for upper management personnel in decision-making positions in order to raise their skills in the procurement of equipment and services, and to provide overall effective leadership. A short course to upgrade the skills of the present maintenance personnel to alleviate the immediate problems is also proposed. Required upgrading of existing technical training facilities, the creation of new facilities and estimated budgetary requirements constitute some of the recommendations. The recommendations have gone through various channels of discussions, and have been accepted in principle. The report is currently under consideration for implementation by relevant government departments.

The military production function

This article analyzes three methods of estimating the military production function which relates military inputs to a measure of military effectiveness. The econometric military production function employs historical data to estimate the relationship between inputs and military effectiveness. A production function estimated during the Vietnam War is provided as an example. The response‐surface military production summarizes the input and output data of a large‐scale military operations research model. This method is illustrated using a model that links maintenance manpower to aircraft sorties. The technological military production function is derived from underlying technological relationships.

Optimization of maintenance organization and manpower in process industries

The objective of maintenance manpower planning is to have the right number of workers with the right capabilities in the right maintenance areas. In this research, a model was developed for optimizing manpower allocation by maintenance area, craft‐type, training level, and in‐house versus sub‐contracted employees, as well as selecting between a centralized versus decentralized organizational structure.

Preliminary evaluation of the anticorrosive properties of aircraft coatings by electrochemical methods

Strict regulations concerning the content of volatile organic compounds (VOCs) and heavy metals (Cr 6+) in aircraft coating systems have increased the economic burden of the United States Air Force (USAF) in the area of coating maintenance. To this end, it is critical to have methods to characterize new coating systems in such a manner that the data can be used to predict accurately and reliably the expected lifetime of the coatings in service. Electrochemical noise method (ENM) and electrochemical impedance spectroscopy (EIS) are two techniques used to monitor extent and rate of corrosion. The USAF is currently employing these methods in order to supplement data acquired from traditional salt-spray methods. ENM and EIS are used to evaluate each component of the coating system and its contribution to corrosion prevention. Preliminary evaluations of an aircraft coating system on aluminum substrate (Al 2024-T3) produces resistance noise values of 10 6 to 10 7 Ω/cm 2. It is hoped that these results will form the basis of coatings that give increased USAF fleet service life and reduction in maintenance manpower and materials costs.

Maintenance manpower modelling for a hospital building complex

A building maintenance manpower simulation model is developed within the case context of a specific hospital complex to investigate the potential gain to be realised using different manpower management and operational procedures. Allowance is made for daily variation in demand for maintenance, sickness and holiday patterns, and the characteristic of different trades. Numerical results are presented for the plumbing trade as a particular example of modelling output.

Development and Practical Use of Paved Track for Revenue Line

In recent years, the destructive force acting on the ballasted track is on the increase with the speed-up of trains and the increase in the number of trains, requiring more labor and expenditure to maintain the track in good condition. On the other hand, it is increasingly difficult to obtain maintenance manpower, because Japan is quickly shifting to a society of elders, and people tend to hate tough works such as manual track maintenance work. Under these circumstances, the Paved Track which is to be laid during the midnight interval on existing line has been developed and improved in order to reduce the maintenance work of the ballasted track on subgrade. This paper describes the track structure and the results of the performance tests of this track.

A Concept of Passive Safety, Pressurized Water Reactor System with Inherent Matching Nature of Core Heat Generation and Heat Removal

The reduction of manpower in operation and maintenance by simplification of the system are essential to improve the safety and the economy of future light water reactors. At the Japan Atomic Energy Research Institute (JAERI), a concept of a simplified passive safety reactor system JPSR was developed for this purpose and in the concept minimization of developing work and conservation of scale-up capability in design were considered. The inherent matching nature of core heat generation and heat removal rate is introduced by the core with high reactivity coefficient for moderator density and low reactivity coefficient for fuel temperature (Doppler effect) and once-through steam generators (SGs). This nature makes the nuclear steam supply system physically-slave for the steam and energy conversion system by controlling feed water mass flow rate. The nature can be obtained by eliminating chemical shim and adopting in-vessel control rod drive mechanism (CRDM) units and a low power density core. In order to simplify the system, a large pressurizer, canned pumps, passive residual heat removal systems with air coolers as a final heat sink and passive coolant injection system are adopted and the functions of volume and boron concentration control and seal water supply are eliminated from the chemical and volume control system (CVCS). The emergency diesel generators and auxiliary component cooling system of “safety class” for transferring heat to sea water as a final heat sink in emergency are also eliminated. All of systems are built in the containment except for the air coolers of the passive residual heat removal system. The analysis of the system revealed that the primary coolant expansion in 100% load reduction in 60 s can be mitigated in the pressurizer without actuating the pressure relief valves and the pressure in 50% load change in 30 s does not exceed the maximum allowable pressure in accidental conditions in regardless of pressure regulation.

A concept and safety characteristics of JAERI passive safety reactor (JPSR)

A JAERI passive safety reactor (JPSR) system has been developed for reduction of manpower in operation and maintenance and increase of safety. The major features are as follows; an inherent matching nature of core heat generation and heat removal, in-vessel control rod drive mechanism units, once-through steam generators, a large volume pressurizer, passive heat removal system, and passive safety injection system. The passive heat removal system consists of residual heat exchangers, gravity coolant injection pools and air coolers. Steady-state analysis clarified that core residual heat during the whole period from shutdown to refueling phase can be transferred by natural circulation to the gravity coolant injection pool and finally to the atmosphere. In case of a large break loss-of-coolant accident (LOCA), steam is discharged and condensed in the gravity coolant injection pool. It was evaluated that the pool water temperature remains below boiling temperature under the large break LOCA condition. In the course of the design study, probabilistic safety assessment (PSA) was used to clarify the safety features and weak points. The results indicated that loss of offsite power is the dominant initiating event. Based on the analyses, improvements of safety system design were proposed.

A Concept of Passive Safety Pressurized Water Reactor System with Inherent Matching Nature of Core Heat Generation and Heat Removal.

The reduction of manpower in operation and maintenance by simplification of the system are essential to improve the safety and the economy of future light water reactors. At the Japan Atomic Energy Research Institute (JAERI), a concept of a simplified passive safety reactor system JPSR was developed for this purpose and in the concept minimization of developing work and conservation of scale-up capability in design were considered. The inherent matching nature of core heat generation and heat removal rate is introduced by the core with high reactivity coefficient for moderator density and low reactivity coefficient for fuel temperature (Doppler effect) and once-through steam generators (SGs). This nature makes the nuclear steam supply system physically-slave for the steam and energy conversion system by controlling feed water mass flow rate. The nature can be obtained by eliminating chemical shim and adopting in-vessel control rod drive mechanism (CRDM) units and a low power density core. In order to simplify the system, a large pressurizer, canned pumps, passive residual heat removal systems with air coolers as a final heat sink and passive coolant injection system are adopted and the functions of volume and boron concentration control and seal water supply are eliminated from the chemical and volume control system (CVCS). The emergency diesel generators and auxiliary component cooling system of “safety class” for transferring heat to sea water as a final heat sink in emergency are also eliminated. All of systems are built in the containment except for the air coolers of the passive residual heat removal system. The analysis of the system revealed that the primary coolant expansion in 100% load reduction in 60 s can be mitigated in the pressurizer without actuating the pressure relief valves and the pressure in 50% load change in 30 s does not exceed the maximum allowable pressure in accidental conditions in regardless of pressure regulation.