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Agrometeorological stations have horizontal solar irradiation data available, but the design and simulation of photovoltaic (PV) systems require data about the solar panel (inclined and/or oriented). Greenhouses for agricultural production, outside the large protected production areas, are usually off-grid; thus, the solar irradiation variable on the panel plane is critical for an optimal PV design. Modeling of solar radiation components (beam, diffuse, and ground-reflected) is carried out by calculating the extraterrestrial solar radiation, solar height, angle of incidence, and diffuse solar radiation. In this study, the modeling was done using Simulink-MATLAB blocks to facilitate its application, using the day of the year, the time of day, and the hourly horizontal global solar irradiation as input variables. The rest of the parameters (i.e., inclination, orientation, solar constant, albedo, latitude, and longitude) were fixed in each block. The results obtained using anisotropic models of diffuse solar irradiation of the sky in the region of Castile and León (Spain) showed improvements over the results obtained with isotropic models. This work enables the precise estimation of solar irradiation on a solar panel flexibly, for particular places, and with the best models for each of the components of solar radiation. [ABSTRACT FROM AUTHOR]

The global carbon emissions from the tertiary sector have increased during the last years, becoming a target sector for carbon capture technologies. This study analyzes the potential application of a carbon capture system (CCS) to the usage of biogas from a livestock waste treatment plant (LWTP) and solid biomass. The proposed BECCS system fulfils the requirement of energy demands of the LWTP and generates electricity. The CCS is sized to consume the biogas produced and the selected operation parameters ensure a high capture efficiency. The BECCS is completed by a Rankine cycle fed by solid biomass and waste heat from the capture process is sized and implemented to produce electricity and steam. The proposed concept handles 1534 kW of solid biomass and 1398 kW of biogas to produce 746.20 kWe and cover the heat demand of a LWTP, 597 kWth. The avoided CO2 emissions sum up to 1620 ton CO2/year. The economic calculations show the limitation of this concept deployment under current prices of electricity and CO2 allowances. Results show the potential feasibility under future scenarios with 5 to 6 payback periods whenever public policies support the use of CCS and EU ETS evolves towards higher prices of carbon allowances. [ABSTRACT FROM AUTHOR]

A lot of autonomous power systems have been designed and operated with different power levels and with special requirements for climatic conditions, availability, operation/maintenance cost, fuel consumption, environmental impacts, etc. In this paper a novel design of an autonomous power system with photovoltaic panels and electrochemical batteries for a shoreline electrode station is analyzed. This station will be constructed on the small island of Stachtoroi for the new high voltage direct current (HVDC) link of Attica–Crete in Greece. The general guidelines of the International Council on Large Electric Systems (CIGRE) and of the International Electrotechnical Committee (IEC) for the power system of lighting and auxiliary loads for these HVDC stations are supplied from the medium voltage or the low voltage distribution network, whereas they do not take into account the criticality of this interconnection, which will practically be the unique power facility of Crete island. The significance of Crete power system interconnection demands an increased reliability level for the power sources, similar to military installations and hospital surgeries. In this research a basic electrical installation design methodology is presented. First, the autonomous photovoltaic power system with the energy storage system (ESS) consisting of electrochemical batteries is preliminary designed according to the relative bibliography. The station power and energy consumption are analytically determined taking into consideration the daily temperature variation annually. Afterwards, a techno-economic optimization process based on a sensitivity analysis is formed modifying the size/power of photovoltaic panels (PVs), the type and the energy capacity of the batteries taking into consideration the operation cycle of PVs—batteries charge and discharge and the battery ageing based on the relationship between battery cycles—the depth of discharge, the daily solar variation per month, the installation cost of PVs and batteries, the respective maintenance cost, etc., while the reliability criteria of expected loss of load power and of load energy are satisfied. Using the proposed methodology the respective results are significantly improved in comparison with the preliminary autonomous power system design or the connection with the distribution power system. [ABSTRACT FROM AUTHOR]

Due to the popularity of indoor positioning technology, indoor navigation applications have been deployed in large buildings, such as hospitals, airports, and train stations, to guide visitors to their destinations. A commonly-used user interface, shown on smartphones, is a 2D floor map with a route to the destination. The navigation instructions, such as turn left, turn right, and go straight, pop up on the screen when users come to an intersection. However, owing to the restrictions of a 2D navigation map, users may face mental pressure and get confused while they are making a connection between the real environment and the 2D navigation map before moving forward. For this reason, we developed ARBIN, an augmented reality-based navigation system, which posts navigation instructions on the screen of real-world environments for ease of use. Thus, there is no need for users to make a connection between the navigation instructions and the real-world environment. In order to evaluate the applicability of ARBIN, a series of experiments were conducted in the outpatient area of the National Taiwan University Hospital YunLin Branch, which is nearly 1800 m2, with 35 destinations and points of interests, such as a cardiovascular clinic, x-ray examination room, pharmacy, and so on. Four different types of smartphone were adopted for evaluation. Our results show that ARBIN can achieve 3 to 5 m accuracy, and provide users with correct instructions on their way to the destinations. ARBIN proved to be a practical solution for indoor navigation, especially for large buildings. [ABSTRACT FROM AUTHOR]

The need for accurate registration of underground objects in the 3D cadastre is becoming increasingly common throughout the world. Research studies conducted in this area mostly focus on objects related to transportation or other public utilities and services. However, in settlements with a long history, apart from new objects, there are also various historical objects underground. Such places are not fully discovered, and sometimes they are not even fully inventoried with surveying methods. The aim of this work therefore is to try to describe the possibility of introducing historical undergrounds to the real estate cadastre created for three dimensions, in case of its creation, and to check ground laser scanning as a method of measuring such objects in order to introduce them to the 3D cadastre. Considerations on the inclusion of underground historical objects into the three-dimensional cadastre database began with conceptual considerations. Their result is the elaboration of UML schemas describing relationships among 3D cadastre objects including underground objects. According to the authors, such underground objects should constitute a completely new class called 'EGB_BuildingBlockUnderground3D' and be part of the legal space of the entire building represented by the class 'EGB_BuildingLegalSpace3D' (the prefix EGB is an acronym of Polish cadastre name 'Ewidencja Gruntów i Budynków'; in English, it stands for 'Land and Building Cadastre'). In order to verify in practice the possibility of introducing historical underground objects into the 3D cadastre database, the inventory of the Underground Tourist Route in Rzeszów (Poland) was used. This route consists of a network of underground passageways and cellars built between the 14th and 18th centuries. The measurement was carried out with the application of the Faro Focus 3D terrestrial laser scanner. The underground inventory showed that at the time the current cadastre of land and buildings in Rzeszów was being founded, the boundaries of the cadastral parcels were established without knowing the location of the underground passageways under the Main Market Square. This resulted in a situation in which the objects located underground became parts of more than one cadastral parcel. If a 3D cadastre is created, such a situation must of course be recorded accordingly. The article proposes solutions for such situations. [ABSTRACT FROM AUTHOR]

When the power source of a voltage source converter (VSC) station at the sending end solely depends on wind power generation, the station is operating in an islanding mode. In this case, the power fluctuation of the wind power will be entirely transmitted to the receiving-end grid. A self-regulation scheme of power fluctuation is proposed in this paper to solve this problem. Firstly, we investigated the short-time variability characteristic of the wind power in a multi-terminal direct-current (MTDC) project in China. Then we designed a virtual frequency (VF) control strategy at the VSC station based on the common constant voltage constant frequency (CVCF) control of VSC station. By cooperating with the primary frequency regulation (PFR) control at the wind farms, the self-regulation of active power pooling at the VSC station was realized. The control parameters of VF and PFR control were carefully settled through the steady-state analysis of the MTDC grid. The self-regulation effect had been demonstrated by a twenty-four-hour simulation. The results showed that the proposed scheme could effectively smoothen the power fluctuation. [ABSTRACT FROM AUTHOR]

As fuel consumption in the transport sector has increased at a faster pace than in other sectors, the use of electromobility represents the main strategy adopted by the automotive industry. In this context, as the number of electrical vehicles (EVs) will increase, it will also be necessary to increase the number of charging stations. The present paper presents a complete solution for charging stations that can be located in the office or mall parking area. This solution includes a mode 3 AC charging stations of International Electrotechnical Commission (IEC) 61851-1 Standard, an EV simulator for testing the good functionality of the charging stations (i.e., communications, residual-current device (RCD) protection) and a software application used for controlling the charging process by the programmable logic controller (PLC). [ABSTRACT FROM AUTHOR]

In this paper, we consider a two-machine job-shop scheduling problem of minimizing total completion time subject to n jobs with two operations and equal processing times on each machine. This problem occurs e.g., as a single-track railway scheduling problem with three stations and constant travel times between any two adjacent stations. We present a polynomial dynamic programming algorithm of the complexity O (n 5) and a heuristic procedure of the complexity O (n 3) . This settles the complexity status of the problem under consideration which was open before and extends earlier work for the two-station single-track railway scheduling problem. We also present computational results of the comparison of both algorithms. For the 30,000 instances with up to 30 jobs considered, the average relative error of the heuristic is less than 1 % . In our tests, the practical running time of the dynamic programming algorithm was even bounded by O (n 4) . [ABSTRACT FROM AUTHOR]