Backup Station Research Articles

A multi-period capacitated facility location problem with maximum travel time and backup service for locating and sizing EMS stations

Emergency medical services (EMS) is a system that provides emergency medical care for incidents involving serious illness or injury. The location of EMS stations plays an essential role in delivering effective and efficient medical services. Numerous location models have been developed for locating and sizing EMS stations. However, it remains challenging to satisfy all EMS planning criteria within a single location model. In this study, a multi-period capacitated facility location problem with maximum travel time and backup service (EMSLSP) is proposed for locating and sizing EMS stations. The most important criteria for EMS planning are taken into account in EMSLSP: the demand changes due to population mobility, the maximum service capacity of an ambulance, the maximum number of ambulances at each EMS station, the maximum travel time from each EMS station to the locations it serves, the full coverage of dynamic demand, the minimum percent of population covered by EMS service in a specific travel time, and a backup station for each demand location in case of need. A case study in Zhengzhou, a large city in China, demonstrates that effective and efficient locations and sizes of EMS stations can be determined by solving the EMSLSP with various planning parameters. Compared with the existing EMS systems, the average ambulance travel time and the percentage of the population served are significantly improved. Simulations of ambulance scheduling confirm that the relocated and resized EMS stations perform better than those in the existing system. The evaluation-optimization-simulation method outlined in this paper provides a comprehensive and effective approach for EMS station planning.

Assessment of Electricity Sector Using Geomatics Techniques: (Ramadi City as a Case Study)

Geomatics involves the collection, management, integration, representation, analysis, modeling and display of geographically referenced information describing both the Earth’s physical features and the built environment. One of the main use of this tool is to estimate electrical energy demand throughout Al Anbar Governorate, which have major problems in this sector with about 750 to 770 MW. The consumption of the city of Al Ramadi is about 200 MW. According to official forecasts by the Directorate of Electricity Networks of Al Anbar, this demand is expected to increase to about 900 MW during the summer of 2020. The present distribution systems in Al Ramadi are mostly overhead. Gradual conversion from overhead to underground systems, particularly at the 11 kV level, is recommended, especially in the central part of the city. This will allow for higher system safety and reliability, and for a much aesthetically improved appearance. This necessitated the construction of additional backup stations. Furthermore, prepared a plan for stations that have been constructed in the year 2020, in order to meet the anticipated demand growth during the planning period. Long-term plan for the Governorate of Al Anbar in order to cope with the increased demand for electrical energy.

How drivers decide whether to get a fuel cell vehicle: An ethnographic decision model

This article develops and tests an ethnographic decision model (EDM) of hydrogen fuel cell vehicle (FCV) adoption using interviews with California residents that either actually adopted an FCV or “seriously considered” doing so before deciding against it. We developed an initial model from 25 semi-structured interviews in which respondents self-described their decision-making processes. We iteratively tested and refined the model in a second round of 53 structured interviews. The final model consists of a first stage that assesses FCV adoption feasibility and a second stage that compares FCVs to other vehicle types. The model ultimately correctly predicts 86.8% of cases in the sample. In the first stage, respondents preferred to satisfy their need for a primary refueling station near home but a substantial number were willing to rely on a station near or on the way to work or other destination. Most drivers required a convenient backup station and a means of managing long-distance trips. Vehicle size options eliminated a few respondents. None rejected FCV adoption due to insufficient driving range. In the second stage, nearly all drivers engaged in some kind of cost comparison, though the factors considered varied greatly. Most opted for what they viewed as the less costly option, although a few FCV adopters and non-adopters were willing to pay more for their more preferred option. EDM is a promising qualitative research method for generating insights into how people navigate the decision whether or not to get an alternative-fuel vehicle.

Перспективи та проблеми розвиту об’єднаної енергосистеми України в умовах її приєднання до енергосистеми Євросоюзу і гіпертрофованого використання у її складі вітрових та сонячних електростанцій

We investigated the key problems of the operation of wind farms within the Ukrainian Integrated Power System (IPS): determination of the type and capacity of regulators capable of ensuring frequency stability in the power system with large wind farms; determination of the competitiveness of wind farms in the electricity market operating in power systems with the provision of frequency requirements. We studied possibilities of technological base and presence of economic basis for the hypertrophied development of wind farms and solar power plants in the Ukrainian IPS, which is taking place now. Using the author's problem-oriented computer software, the processes of frequency and power regulation in the IPS of Ukraine with large wind farms were studied and it was found that their reliable operation is possible due to the use of powerful batteries. Based on this fact, with the use of a progressive methodology for determining the weighted average cost of electricity production during the life cycle based on market relations, it was established that none of the configuration options for the complexes in the wind farm - the regulator - the backup station can compete economically with traditional technologies even with high payment for greenhouse gas emissions. Using the results obtained, an analysis of the law "On alternative energy sources" (hereinafter - the law on "green" tariff) in the conditions of the IPS of Ukraine regarding wind and solar power plants was conducted. This law was not economically and environmentally sound as early as at the moment of its adoption (2003) and, at the same time, created large preferences for owners of wind and solar power plants (extremely high tariffs for their power plants; charging costs for regulating capacities to the account of the consumer, the principle of "take or pay" in relations between owners of wind and solar power plants and the electricity market; obligations of the energy system to give permissions for connection of wind and solar power plants without limitations, etc.). As a consequence, as of the end of October 2019, the total capacity of functioning and declared to be commissioned WPPs and SPPs was about 12.55 GW, and according to existing forecasts by the end of this year this indicator will increase to 18 GW. IPS of Ukraine will not be able to accept such capacity of WPPs and SPPs (sources with zero guaranteed capacity) (the autumn maximum in the specified period was 21.3 GW). To analyze the effect of the law on the “green” tariff for the future state of Ukrainian energy system and the electricity market, the total costs were calculated, which the consumer will have to compensate in the situation when 7.75 GW of WPSs and 4.8 GW of SPPs work in the power system (volumes, stated as of the end of October 2019). At the same time, consumer expenditures will annually amount to 3.565 billion US dollars for the received 18.166 billion kWh of electricity. An alternative is calculated when the same amount of electricity is produced at coal-fired power plants. To do this, only 3.45 GW of their capacities is needed, and the total consumer expenses will amount to 286 million US dollars, that is 12.47 times less than in the case with the use of wind farms and solar power plants. It is shown that in the current state of all the profits that the electricity market in Ukraine receives, it will not be enough for settlements with the owners of wind farms and solar power plants. Therefore, it is urgent to adopt a law that repeals all the preferences for the construction and operation of wind farms and solar power plants in the Ukrainian energy system. Otherwise, the energy market in Ukraine will go bankrupt, and the country's economy will default.

Evaluation of redundant configurations and backup stations to support fault tolerant flow line design

The fourth industrial revolution, namely Industry 4.0 drive the development of technologies as intelligent industrial robots, share information among workpiece, equipment, and machines, artificial intelligence for the analysis of information and support self-adapting activities. These technologies enable a station of automated flow line to perform different operations on different products without the need of a time-consuming and costly setup. The information sharing among items and other machines of the line allows selecting other stations to process the operation if some problem occurs. This research proposed a framework to support the design of automated flow lines with redundancies of the operations on downstream stations. The framework includes mathematical models to provide design alternatives and a simulation model to evaluate the performance measures. The redundancy models are compared to a configuration with backup stations. The results show how the framework provides information to support the decision maker to select the design alternative considering the operative condition. The model with one redundancy for each operation leads to better results, while the increase in the number of redundancies of each operation reduces the performance. The introduction of the backup station is the better solution, but this is characterized by investment costs in further machines.

Redundant configuration of robotic assembly lines with stochastic failures

One of the main challenges in the operation of robotic assembly lines is the occurrence of failures. Due to the connection of the stations via a material handling system, failures at one station often result in throughput losses. To some extent, these throughput losses can be reduced by installing buffers between the stations. However, the installation of buffers requires considerable investments and scarce factory space. Due to the advances of manufacturing technologies that form the foundation of ‘Industry 4.0’, new solutions to reduce failure-related throughput losses open up. One solution is a redundant configuration, in which downstream (backup) stations automatically take over the operations of failed stations during repair time. The throughput loss in these situations depends on the allocation of operations and the assignment of backup stations. Existing approaches in the literature that consider redundancies in the configuration of automated lines neglect the resulting production rate. Instead, the lines’ level of redundancy is used as a surrogate measure for optimisation. We present a genetic algorithm for the redundant configuration of robotic assembly lines with stochastic failures to maximise the production rate of the line. In a numerical analysis, it is demonstrated that this approach allows for productivity improvements.

QUEUEING SYSTEMS WITH N-LIMITED NONSTOP FORWARDING

We consider a queueing system with N-limited nonstop forwarding. In this queueing system, when the server breaks down, up to N customers can be serviced during the repair time. It can be used to model an assembly line consisting of several automatic stations and a manual backup station. Within the framework of <TEX>$Geo^X/D/1$</TEX> queue, the matrix analytic approach is used to obtain the performance of the system. Some numerical examples are provided.

Live Well Display and Automated Data Analysis Improve Managed-Pressure-Drilling Operations

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 25164, ’Live Well Display and Automated Data Analysis To Improve Timely Well-Control and Drilling-Optimization Decision Making in MPD Operations’ by Ferhat Gumus, Ilia Pobedinski, Don Hannegan, Khaydar Valiullin, and Douglas R. Simpkins, Weatherford, prepared for the 2014 Offshore Technology Conference, Houston, 5-8 May. The paper has not been peer reviewed. Ideally, a managed-pressure-drilling (MPD) system should have not only highly accurate sensors measuring critical mud-flow data and automated chokes to maintain desired annular pressure precisely but also the ability to aggregate, analyze, and display this real-time information on monitors on the rig floor and in remotely located centers. This paper describes a number of system enhancements, including the ability to display and analyze not only the critical parameters of drilling hydraulics but also other information that allows different perspectives in considering the closed-loop system. Introduction MPD offers a number of accepted applications while increasingly being considered for any other operations requiring precise pressure control. There has been a growing trend for MPD providers to be more involved in drilling, well-construction, and completion operations as their safety value and effectiveness is realized. A new platform has been developed for the next-generation MPD system. The goal was the development of a user-friendly system that will improve critical decision making and execution by providing enhanced visual feedback and interaction. This may include pre- engineering, operation and post-job analysis, automation of time- and pressure-sensitive tasks, multiple software engines being able to evaluate limits, and multiple components being controlled in one place. System Architecture The new platform has been developed by use of a layered architectural approach and an object-oriented style. The layers of an application may reside on the same physical computer or may be distributed over separate computers; the components in each layer communicate with components in other layers through well-defined interfaces. Distributing the layers over multiple physical tiers improves scalability, fault tolerance, and performance, which increases availability. There are also multiple physical components making up the system— for example, an intelligent control unit (ICU) houses electronics, including a programmable-logic controller. Singleor multiple-ICU-equipped systems can be connected through a universal switch that not only will serve as a central hub but also will provide plug-and-play ability for wellsite-information-transfer-specification (WITS) communication and additional analog sensors when required. The ability to function as a local WiFi hot spot, without interrupting operations or portability, and enabling a secure connection to external networks are other requirements for this universal switch. In addition, multiple computer stations will be hosting database servers, data-acquisition processes, real-time hydraulics, and other engines. Although all computer stations (panels) are identical on the background, they will have dedicated roles and will work in a hierarchy, with one being designated as master while the other stations are running as backups. The master station will collect all data needed, execute calculations, store data in a database, and publish data to subscribers. Backup stations will check the “heartbeat” and will store data received from the master. In this way, valuable real-time data will be copied safely across multiple computer stations. To achieve fail-safe operation, in case of master-station failure, the master role will be transferred automatically to one of the backup stations.

Ground Contact Analysis for Korea's Fictitious Lunar Orbiter Mission

In this research, the ground contact opportunity for the fictitious low lunar orbiter is analyzed to prepare for a future Korean lunar orbiter mission. The ground contact opportunity is basically derived from geometrical relations between the typical ground stations at the Earth, the relative positions of the Earth and Moon, and finally, the lunar orbiter itself. Both the cut-off angle and the orbiter's Line of Sight (LOS) conditions (weather orbiter is located at near or far side of the Moon seen from the Earth) are considered to determine the ground contact opportunities. Four KOMPSAT Ground Stations (KGSs) are assumed to be Korea's future Near Earth Networks (NENs) to support lunar missions, and world-wide separated Deep Space Networks (DSNs) are also included during the contact availability analysis. As a result, it is concluded that about 138 times of contact will be made between the orbiter and the Daejeon station during 27.3 days of prediction time span. If these contact times are converted into contact duration, the duration is found to be about 8.55 days, about 31.31% of 27.3 days. It is discovered that selected four KGSs cannot provide continuous tracking of the lunar orbiter, meaning that international collaboration is necessary to track Korea's future lunar orbiter effectively. Possible combinations of world-wide separated DSNs are also suggested to compensate for the lack of contact availability with only four KGSs, as with primary and backup station concepts. The provided algorithm can be easily modified to support any type of orbit around the Moon, and therefore, the presented results could aid further progress in the design field of Korea's lunar orbiter missions.

MARTe at FTU: The new feedback control

Keeping in mind the necessities of a modern control system for fusion devices, such as modularity and a distributed architecture, an upgrade of the present FTU feedback control system was planned, envisaging also a possible reutilization in the proposed FAST experiment [1]. For standardization and efficiency purposes we decided to adopt a pre-existent ITER-relevant framework called MARTe [2], already used with success in other European Tokamak devices [3]. Following the developments shown in [4], in this paper we report on the structure of the new feedback system, and how it was integrated in the current control structure and pulse programming interface, and in the other MARTe systems already in FTU: RT-ODIN [5] and the ECRH and LH [6] satellite stations. The new feedback system has been installed in the FTU backup station (known as “Feedback B”), which shares the input signals with the actual feedback system, in order to simplify the validation and debug of the new controller by testing it in parallel with the current one. Experimental results are then presented.

A multi-period double coverage approach for locating the emergency medical service stations in Istanbul

We consider the multi-period location planning problem of emergency medical service (EMS) stations. Our objective is to maximize the total population serviced by two distinct stations within two different response time limits over a multi-period planning horizon. Our aim is to provide a backup station in case no ambulance is available in the closer station and to develop a strategic plan that spans multiple periods. In order to solve this problem, we propose a Tabu Search approach. We demonstrate the effectiveness of the proposed approach on randomly generated data. We also implement our approach to the case of Istanbul to determine the locations of EMS stations in the metropolitan area.

Canadian plans for participation in GSETT 3

The Geological Survey of Canada (GSC) is making preparations for Canadian participation in GSETT 3 but will be unable to make a formal commitment until the necessary resources have been secured. As Canada is expected to provide at least four alpha stations, and a significant number of beta stations, the financial resources that will be needed are substantial, even though in many respccts the GSC is, with the recent modernization of the Yellowknife array and the ongoing installation of the Canadian National Seismograph Network (CNSN), well positioned to make a significant contribution to GSETT 3. The CNSN currently (October 1993) consists of 17 broad band stations and will grow to 23 and 33 such stations by December 1993 and December 1994 respectively. Some 40 50 short period stations will complete the network. Data from all sites are continuously telemetered in real time to network acquisition centres in Ottawa and Sidney, British Columbia, archived to optical disk, and kept on line in a 72 h ring buffer. Most of the broadband sites could serve as either alpha or beta stations once the necessary software for continuous data transfer, or on request provision, of data from the selected sites has been completed. This software wili be configured so that changes in station selection are easy to implement, and this will provide considerable flexibility to the GSETT 3 planning and operations working groups in selecting the optimum network. Backup stations can be designated in the case of station failures, and the network centre in British Columbia will serve, at least for beta stations, as a backup NDC to that in Ottawa. Data from. the Yellowknife array are collected in Yellowknife and forwarded in ten minute files to Ottawa, where processing is completed and the results archived. This arrangement would not meet the deadlines for receipt of alpha station data at the IDC and new hardware and software will be needed to forward the data more immediately from Yellowknife to Ottawa. Although the procedures and formats for both alpha and beta station data have not yet been agreed upon, or even discussed, by the GSE, it is apparent that new facilities will be re quired in Ottawa to multiplex and reformat data for transmission to the IDC. We anticipate that a dedicated 56 kbaud link will be needed between Ottawa. and Washington.