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We consider the propagation of light in the generalized Born-Infeld-type nonlinear electrodynamics. The speed of light in a uniform electric or magnetic field is not constant and can be described by the effective index of refraction. When the background field is non-uniform, the path of light is bent by the gradient in the index of refraction. We compute the bending angles of light passing the electric field by a Coulomb charge and the magnetic field by a magnetic dipole using the trajectory equation based on Snell's law. In the limit where the classical Born-Infeld parameter is infinite the bending angles reduce to the bending angles from the Euler-Heisenberg Lagrangian. [ABSTRACT FROM AUTHOR]

Due to the high efficiency and power factor of rechargeable batteries, they require high-power-density and bridgeless single-conversion battery chargers. In this paper, we introduce a bridgeless AC-DC c0nverter that can provide high efficiency and low reverse-recovery losses. The proposed device features a series-resonance current injection system and a linear feedback algorithm to control the output power. Because of the simplicity of the circuit construction, it has a high efficiency and power factor. The suggested charger's theoretical concepts are tested in an actual setting using a 1.7 kW prototype. [ABSTRACT FROM AUTHOR]

The paper presents a proposal for a lighting project for the football field of FC Junak from Sinj, with 20 optimally positioned and aimed DALI controllable LED floodlights, mounted on four proposed newly designed lighting poles, which would meet the requirements for competitions, and with the possibility of powering only six floodlights per pole, which is enough for lighting during training. The presentation of the appearance of the designed lighting poles, the optical, mechanical and light-technical properties of the selected floodlights and an example of the cost sheet are given. Illumination calculations were performed and analysed in the Dialux program, for both cases of use, for competitions and public events and for training. Designed technical-light solutions for football field lighting are shown via tables, floor plans and spatially for both cases. An estimate of the annual consumption of electricity is given. The execution of the project would be significant for the city of Sinj and its surroundings, which would provide new generations with a functional football field, and potentially provide its citizens with a newly lit space for attractive, not only sporting, but also cultural, artistic and other events. This would allow the city of Sinj to join the current renovation and construction process of sports infrastructure in the Republic of Croatia. Since the project is estimated at 750000 euros, which is a large expenditure for an investor, it was proposed to apply for a tender for co-financing the construction, renovation, maintenance, equipping and reconstruction of sports buildings by the Ministry of Tourism and Sports. The option of a cheaper project, with less reliable floodlights from the Chinese market, was also taken into account and a comparison with the proposed project was given. Due to environmental standards, only LED floodlight lighting was taken into account for both cases. [ABSTRACT FROM AUTHOR]

The global shift towards renewable energy sources has led to the implementation of energy-saving policies and laws worldwide. In this context, daylighting has emerged as an environmentally friendly method to manage natural light flow in building interiors. The construction industry has recognized the importance of utilizing natural illumination to reduce energy usage and power consumption while avoiding overheating. With electric lighting accounting for over 30% of a typical building's energy consumption, particularly during the day, the integration of daylighting systems can decrease energy usage by at least 50%. Moreover, effective shading with daylight can significantly reduce cooling energy. In Myanmar, architects and developers are increasingly focusing on daylight management to create sustainable building designs and reduce energy consumption. This study aims to explore successful daylighting and daylight management systems installed in buildings by conducting a literature review, case studies, and an overview of daylighting management methods. By highlighting the importance of daylighting and its potential benefits, this study contributes to the ongoing efforts to achieve sustainable development through the implementation of energy-efficient building designs. [ABSTRACT FROM AUTHOR]

The electric field of light at the center of a one-dimensional mirrored multilayer structure consisting of two consecutive dielectric media A and B in the unit cell, namely AB mirrored multilayer structure, is well-known to rise exponentially by increasing the repetition number of the unit cell, in which the refractive index of A is larger than that of B. What happens if we now consider more than two dielectric media in the unit cell? In this study, we show that the electric field enhancement for an odd number of dielectric media in the unit cell, e.g. ABC structure, oscillates between zero and a certain finite value when increasing the repetition number. Meanwhile, for an even number of dielectric media in the unit cell, e.g. ABCD structure, the electric field at the center of the multilayer structure can be enhanced significantly when increasing the repetition number by simply tweaking the refractive index ratios of the dielectric media in the unit cell. Furthermore, the even number of dielectric media in the unit cell may fine-tune the electric field enhancement with better precision to obtain the desired value for photonic applications. [ABSTRACT FROM AUTHOR]

PMSM is one type of motor widely used for EV (Electric Vehicle), especially Light EVs. Sensorless control is one of the breakthroughs to reduce the use of speed sensors in PMSM because it is susceptible to noise and high cost. This research focuses on solving senseless speed control for low-speed applications. MPC-EKF is proposed to solve this problem. For speed control, there are two proposed algorithms, FCS-MPCC as inner-loop and MPSC as outer-loop. The EKF is used as an estimator to get the speed and angular position of the motor. The EKF output is used as direct feedback for speed control. The simulation results show that the proposed algorithm is effective for sensorless speed control applications, as indicated by the speed error value eω < 0.2rad/s when steady-state conditions. [ABSTRACT FROM AUTHOR]

This paper presents the design and examines the energy statistics of a light electric car with a 1 kW rated motor. The light electric car incorporates two energy storage sources to power its powertrain: the first is a lithium battery pack, and the second is a compressed cylinder hydrogen storage. The latter is used to fuel the polymer electrolyte membrane fuel cell (PEMFC). The 1 kW PEMFC in the designed light electric car is used as a range extender. The system design aims to increase the light electric car's autonomy by the implementation of a range extender system that allows the car's battery to make multiple trips in one or several days without needing to charge it by connecting it to a power source. Data were collected in both battery and hybrid (battery+fuel cell) modes. A statistical study of the total energy and distance traveled collected during driving in the battery and hybrid modes indicated that the hybrid mode provided more reliability. [ABSTRACT FROM AUTHOR]

Non-spherical (anisotropy) metal nanomaterials possess a great potential in a wide range of applications. Its catalytic, optical, and electronic properties can be altered by the change of the shape and the size. In the field of plasmonic, the light interaction with matter in the nanometer regime depends on the size and shape of the nanomaterials. Through the better understanding and control of atomic world, it is possible to convert light to localize electric fields and to route light to desire location with nanometer precision. Silver metal is probably the most important metal in the field of plasmonic because it supports a strong surface plasmon and accommodate the broad range of spectrum. Fabrication of nanoparticles for certain application such as catalysis and optical demands in the control shape, size, and surrounding media. Silver nanocubes with different edge length were successfully synthesized through polyol synthesis method. The narrow particle size distribution of the as-synthesized silver nanocubes indicates a high uniformity of the size. The different size of silver nanocubes exhibit different light absorption capability. [ABSTRACT FROM AUTHOR]

Installation of a solar home system is often ineffective because it may not perform a thorough analysis. How PV mini-grid design can ensure continuity of power service and optimization of equipment selection is often not taken into calculation carefully. This research aims to determine the performance of the SHS (solar home system) in serving lights and prove the suitability of the results of the planning analysis with the real situation. The method used is a calculation analysis that considers the efficiency aspect of each equipment in the system. Research shows the consumption of electrical energy from the results of 2142 wh analysis and 2173 wh measurements, the difference is due to fluctuating user needs, energy consumption varies from 1870 wh to 2763 wh. Lamps with a total power of 308 watts are divided into 21 lamps capable of being served by a 1600 Wp solar module, 350 Ah 24 Volt battery, 24 volt 60 Ampere SCC and 1000 watt inverter with service continuity maintained with fluctuating weather conditions. The addition of the number of solar modules is doubled from the calculation results, causing the battery to reach its full level at noon or 11:45 WIB. The addition of the average battery voltage is 25.7 volts, the average battery voltage drop after 12 hours of loading is 23 volts with values varying from 22.14 to 23.77 volts. This research is expected to be a reference for the calculation and installation of SHS effectively. [ABSTRACT FROM AUTHOR]

Asymmetric electric force exerted due to the electric field in the light wave is studied and found to responsible for photoelectric effect. The study implies that the ejected photoelectrons are always in the plane of electric field in the light wave. It further suggests that the asymmetric electric force, expressed in terms of field-field interaction seems to be the actual magnetic force, therefore, the magnetic force in EM waves should be frequency dependent. As frequency increases, the magnetic force exerted by EM waves increases which may be verified experimentally. It further suggests that the electric field and magnetic field in EM waves are not in phase. They should have phase difference of 90 degrees. [ABSTRACT FROM AUTHOR]

This paper intends to provide brief information about various components in an electric moped and propose an optimal design for Chassis. To attain optimal design, a conventional moped chassis is identified as a reference and according to the specifications and features of an electric vehicle, this conventional chassis is modified. The Model is designed in CATIA and simulation was performed in ANSYS giving a desired fabricated model which is eccentric and light-weight. [ABSTRACT FROM AUTHOR]

An analysis presented in the paper reveals that most equipment requires a DC power supply (low voltage and low current) rather than an AC power supply, like computers and peripherals, audio-video players, food preparation. Moreover, there is the possibility that through minimal adaptations and other equipment they can operate in DC microgrids. A validation for one or another microgrid types, when the AC grid has priority, is based on an in-depth study. There are currently consumers (especially in the home appliance field) that can be used successfully in bothmicrogrids (AC and DC). This category of receivers includes AC electrical light sources, which study and analysis of compatibility in DC network, will be detailed in the paper. The research results conduct to the conclusion that most of the AC consumers used nowadays, are easy to use and adapt to a DC microgrid, like the residential low voltage electric network. Paper will focus only to a detailed analysis for one lightning source. [ABSTRACT FROM AUTHOR]

Enclosed internal corridors are long circulation areas with no window provisions, and they require electric lighting to be switched on for 24 hours continuously to operate. Depending on the designs, some corridor designs have openings for daylight at the ends, while others supplement daylight at the middle. Most parts of these corridors, however, are usually dark and consuming a lot of non-renewable energy from artificial light. This paper explores how enclosed internal corridors could get the benefits of daylight de-pending on the corridor wall designs. It explored how %DF (Daylight Factor) less than 1%, especially in Malaysia where the skies are bright, could still be beneficial and useful. The standard illumination required for corridors is benchmarked. Fieldwork for %DF measurements was taken in selected points at an enclosed corridor of a hostel building on a typical overcast day. A scaled model of similar design was built and experimented in the artificial sky to get the same set of readings; followed by simulation using Radiance. Results showed that the readings calibrate well between fieldwork compared to the scaled model and simulation, with less than 10% differences. Corridor walls are usually opaque resulting in very dark situations relying solely on artificial lighting. The study further investigated the extent of daylight which can be borrowed to light the internal enclosed corridors. This was carried out by experimenting on the various types of corridor wall designs with added transparent or glazed areas to enable daylight penetration. The designs experimented with various horizontal and vertical alternatives. The effects of these new corridor wall design on daylight distribution in corridors are investigated by Radiance simulations. Results were compared to the base case which was the normal. The findings showed that the newer designs of corridor walls could provide daylight to corridors with significant levels of improvements. Even though the %DF found were very low, outdoor illuminance in tropics is high therefore it was sufficient for corridor lighting. Corridors with 50% glazed areas in a 4 strips horizontal design were found to perform the best for allowing borrowed daylight to occur. [ABSTRACT FROM AUTHOR]

The article presents the results of research and analysis of vibrations of an on-board power unit developed for a 48V electric light commercial vehicle. Auxiliary power unit consisting of a single-cylinder spark-ignition internal combustion engine driving a three-phase synchronous generator was designed and made as a result of the work of the Student Research Group of Internal Combustion Engines at Cracow University of Technology. On the one hand, the auxiliary power unit makes it possible to increase a range of the vehicle with electric propulsion, on the other hand, the operation of a single-cylinder engine on its board negatively affects the comfort of passengers. The presented work was undertaken in order to quantify the impact of an operation of the range extender on the electric vehicle body vibrations and to evaluate the effectiveness of the used vibration-damping elements of the power unit. The carried out experiments indicated the most beneficial configuration of the damping elements. It was also found that the use of the muffler with a catalytic converter enabling exhaust gas aftertreatment increased the range extender vibrations in the high engine speed range and generator load, which was not the case with the factory exhaust system. In the final part of the work, the possibilities of limiting the vibrations generated by the single-cylinder engine used in the project were also indicated. [ABSTRACT FROM AUTHOR]

During the past decades, there has been a dramatic increase on the average temperature worldwide, and it is nowadays undeniable the fact that climate change is going through an irreversible process leading to global warming. In line with the target set in the Paris Agreement, Argentina has launched as from 2016 several measures in the electricity sector oriented to carbon dioxide (CO2)-the main greenhouse gas (GHG)-emissions reduction, but there is still a lot of work to be done in the transport one, the second largest CO2 emitting sector. This work, derived from the Master's Thesis work [1], projects the effect of battery electric vehicles' (BEV) introduction in the carbon footprint of Argentina up to year 2050, by simulating different scenarios of the energy demand on the electricity generation and transport sectors, both coupled, and comparing them to a baseline scenario evolving both of them separately in a business as usual (BAU) basis. For the sake of it, the evolution of macro variables will be estimated as from year 2017 [2]-[3], and the relevant characteristics will be mapped with a top-down approach serving as the input data for the simulation model. Finally, it will be established a bridge between these, in which marginal CO2 emissions from the electricity demand will be calculated; this means, considering surplus demand from batteries' daily load profile [4]. These results will be aggregated for each scenario and compared to the ones initially estimated as the baseline. The obtained results will prove that the introduction of this technology under certain assumptions brings important benefits in terms of GHG emissions, and will contrast the negative effects of an unplanned implementation as well. [ABSTRACT FROM AUTHOR]

The use of glass for facade design has increased in resect years, especially in Taiwan, for prevent the earthquake as an emergency exit furthermore for harvesting the daylight and aesthetic. However the daylighting from the large window bring one critical issues, glare. Users tend to use curtain to block the glare which increase the electric lighting consume. Thus, in this paper summarized and examines the existing lighting conditions of the classroom TR309, National Taiwan University of Science and Technology (NTUST) for as an Integrated Studio for Sustainable Design (ISSD) for Architecture Department. In this study, the classroom was simulated with DIVA for Rhino simulations. The programs provide tools for efficient integration of daylighting issues in the design proces. This research intends to achieve the interior classroom design using lighting technology to create a classroom that contributes to a more humane (involving student behaviour) and saving energy. [ABSTRACT FROM AUTHOR]

In this paper the problem of illumination control in a lighting system with networked lighting devices is examined. The luminaries have fluorescent light sources dimmable by a local controller. The optimal dimming values are calculated according to the user and legal requirements for illuminance of different workspaces and their actual illumination levels are measured by light sensors. A closedloop lighting device control algorithm is used for obtaining the set illumination values. So a distributed and energy optimised illumination control with the use of daylight can be effectively implemented. The proposed approach is evaluated in lecture rooms and office environments. [ABSTRACT FROM AUTHOR]

This paper investigates the requirements of daylight in conjunction with sustainable building design and the challenges of assessing daylighting in buildings. Daylight is an available resource that adds value both architecturally and economically. Qualitative daylighting design has the capacity to increase user satisfaction and productivity. Moreover, when consciously exploited and used together with energy-efficient lighting and controls, daylighting can reduce energy consumed by electric lighting by up to 70% with immediate results on decreasing overall building energy use. Successfully designing daylighting into buildings in a way that leads to high levels of visual comfort and also reducing energy use of the building is a complex and challenging process, demanding daylighting considerations at all stages of the building design process, from site planning through architectural, interior, and lighting design evaluation, to the conscious design of the building elements such as windows and skylights, which admit daylight in buildings. Investment in daylight generates a large return in term of considerable reductions in energy consumption and CO2 emissions [ABSTRACT FROM AUTHOR]

The Illuminating Engineering Society (IES) recommends illuminance and uniformity targets (1), which are at times difficult to achieve, especially with daylight only. Assessing visual comfort in daylit environments such as libraries is important, particularly since libraries often have large daylit spaces. The term "daylight shadow" is defined as the shadow produced by daylight and objects as opposed to shadows produced by electric light and objects. Architects and artists widely acclaim that shadows are critical elements that affect the building occupants' emotions and that, consequently, they warrant more empirical research. This study examines the visual comfort related to daylight shadows. The methodology uses both quantitative and qualitative approaches. In the summer of 2012, librarian interviews, pre-tests, and post-test surveys were conducted in three Oregon libraries. Based on survey responses from 93 subjects, the data showed there was a tendency for people to feel more visually comfortable if they had positive perceptions of daylight shadows. [ABSTRACT FROM AUTHOR]

Spectral analysis of electric light sources was carried out. Emission spectra were measured for markedly available lamps used for illumination houses and offices. Amount of UV energy in energy saving lamps spectra is up to 15%, in incandescent lamps 2%, in LED is within experimental error 0%. Perhaps wearing protective glasses for reading should be considered in a case of energy saving lamps light, similarly as in a beach, snow or mountains, sun protecting glasses are recommended. [ABSTRACT FROM AUTHOR]