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In this paper, the simulation of various XOR-XNOR gates are implemented and novel 1-bit Full Adder (FA) using mirror circuits and the transistor sizing method, which uses a numerical computational PSO algorithm to reduce the size of the transistors, are simulated. These two techniques allow for greater optimization in terms of power consumption and delay. These circuits will be simulated using the Cadence Virtuoso tool and a 180nm technology model. In this comparison, the effects of various factors, such as supply voltages, threshold voltages, and output capacitances, result in a reduction of the Power Delay Product (PDP) and Energy Delay Product (EDP) by up to 23.4 % and 43.5 %, respectively. [ABSTRACT FROM AUTHOR]

In this work, experimental study for the chaotic dynamics of a quantum well semiconductor laser (SL) (1310 nm wavelength) with anoptical loop mirror is investigated. The spikesareintroduced by configuring this external cavity type. Making one arm from this cavity be attenuated led to retardation for it. Disturbance in longitudinal lasing mode resulted in chaotic spectrum. Bandwidth for this signal is very limited and changeable under the attenuation ratio. In comparison to pure optical feedback, the achieved signal is lower and evolved from kHz band (in 4.3 v bias voltage) to MHz band (with higher voltages i.e., 4.7 and 4.8 volt). The first range included 300% higher amplitudes for the lasing modes, while the later was equivalent to the random like signal amplitudes. Such a range can be employed for laser wavelength fine tuning applications with the benefit of not disturbing the laser medium. This results opens the door for mixing resulted signal with another oneprimary subjects to pure optical feedback. [ABSTRACT FROM AUTHOR]

This study is about the production of tinted film for helmet visors and windshields that possibly meet the specifications. The use of tinted film must comply with the regulations from Road Transport Department Malaysia. The permitted visible light transmission (VLT) percentages of 70% for the front windscreen, 50% for the front side windows, and 30% for the rear windows and the rear windscreen. Nowadays, polyethylene terephthalate (PET) was used as a plastic film window and distinguished primarily by the fact that a wide range of molecular weights and degree levels are generated in a single multi-product polymerization process. Natural and synthetic dyes differ fundamentally in terms of stability and cost. Furthermore, most synthetic dyes are not biodegradable, they accumulate on lands and in river causing ecological problems. This research used onion peels as natural dyes for the fabrication of tinted film. The objective of this research is to study the properties of onion peels as a tinted film using lux meter for brightness, Scanning Electron Microscope (SEM) for morphology, Fourier Transform Infrared Spectroscopy (FTIR) for bonding and Ultraviolet-Visible Spectroscopy for absorbance properties. Polyethylene Terephthalate (PET) granules, glycerine, acetic acid and onion peels were mixed for the fabrication of tinted film. The result for tinted film shows less light penetrating the glass mirror. While the morphology shows an uneven surface and it is supported by a FTIR and UV-Visible that shows there is a peak shift in onion peels tinted film. Therefore, onion peel dye shows a higher possibility as a tinted film for helmet visors and windshields. [ABSTRACT FROM AUTHOR]

We investigate sphaleron solutions of the field equations in the modified mirror model. This model is based on SU(3)1 ⊗ SU(3)2 ⊗ SU(2)L ⊗ SU(2)R ⊗ U(1)Y ⊗ U(1)X gauge group. Different from the usual Weinberg-Salam theory, we will have two types of fields, the ordinary (standard model) and its mirror partners. In this paper, we will focus only on the case when the doublet scalar of the mirror sector has a very large vacuum expectation value (VEV) compared to the VEV of the SM Higgs. We study two scenarios related to the sphaleron solutions in this model, depending on the value of the coupling α. For the case of α = 0, each sector has its sphaleron and the sphaleron energy depends on the VEV of scalars for each sector. In the case α ≠ 0, we find that the sphaleron energy in the SM sector can be either increased or decreased depending on the relative sign of the coupling α. [ABSTRACT FROM AUTHOR]

The key benefit of the simulated PZT type-8 material two axis MEMS Scanner for LIDAR Applications is cost and size reduction. Microscopy, LiDAR, and biological imaging all use MEMS technology in conjunction with the proper mirrors and control systems. A low voltage scanning mirror is proposed in this article to take into account applications like LiDAR, particularly for UAV (Unmanned Aerial Vehicle) and gesture recognition. A lever structure made of suitable materials, such as PZT ceramic, can achieve Low Power Consumption although the scanning mirror should have a respectable FOV (Field Of View). To achieve a wide FOV and dual axis MEMS mirror acquisition, the proper activation mechanisms are used. [ABSTRACT FROM AUTHOR]

Proper heliostat alignment is a crucial point for the optimal operation of Solar Power Tower plants. To quantify canting errors in heliostat facets, we propose a target reflection technique that uses computer vision to overcome the limitations of existing methods. In our approach, a high-resolution camera is mounted on the back structure of a target heliostat. The reflection of the object heliostat mirrors contains the reflection of the back structure with the camera. This paper explains the 7-step methodology that ends up with the comparison of detected and modelled reflected borders. Preliminary results in a lab-scale testbed show a technique's uncertainty of around 0.2 mrad, including the experimental error associated with the manual adjustment of facets. [ABSTRACT FROM AUTHOR]

Solar mirrors are usually implemented on desert sites despite the arid meteorological conditions to take advantage of the high irradiation rate. These sites are characterized by high wind speeds which transport sand, dust and fine particles from the ground to the reflectors surface causing significant mechanical damage. Two major performances degradation could be observed in this type of environment: erosion and soiling. These two phenomena are impacted by several parameters including the nature of the mirror surface (coated, uncoated...), the weather conditions of the site (wind, humidity, rain...) and the mirrors configuration (inclination and orientation). In order to assess the impact of solar mirrors configuration, a study was carried out by exposing several types of solar mirrors in a desertic site on a special rack with varying inclination angles (0°, 45°, 90° and 135°) and facing two different directions (North and South). The weather data analysis showed that the dominant wind speeds come from the north direction, so the samples oriented in this direction undergo more degradation and the 90° inclination reach the greatest reflectance loss values. After 12 months of exposure, unexpectedly, the hard-coated samples show significant loss values compared to uncoated and antisoiling samples. [ABSTRACT FROM AUTHOR]

Concentrating Solar Power (CSP) plants must consider and minimise the effects that losses in mirror reflectivity, due to soiling, have on limiting operational efficiency. This study presents an overview of the factors that impact the rate of soiling and degradation of reflectivity. These factors include geographical location, mirror positions within the solar field, mirror materials, mirror exposure conditions (inclination angle, height, and orientation), weather factors (rainfall, wind speed, and humidity), and the time of the year. An overview of two types of mirror reflector cleaning processes is also provided, with the effects each has on improving reflectivity being outlined. Traditional, more popular, and most widely available water-based methods have been considered over dry methods, which are still in the early stage of development. This study aims to clearly define and explore each mirror efficiency limiting factor and to present an overview of cost-effective cleaning methods, strategies, and approaches in maintaining or improving optimal mirror reflectivity. [ABSTRACT FROM AUTHOR]

Solar Power Tower systems use a series of tracking mirrors (heliostats) to concentrate sunlight into a central receiver. Each heliostat is composed of a series of smaller mirrors, called facets, that need to be correctly aligned to focus the beams into the receiver. A common problem associated with this technology is finding canting errors in the heliostat facets. One of the techniques proposed to overcome this problem includes using computer vision to accurately locate the facets and then using a heliostat's theoretical model to calculate the errors. This paper describes the computer vision mechanisms necessary to perform facet detection, proposing a quasi-automated process that minimizes the need for human input. Results show that the quasi-automated solution provides low errors in distance and slope with respect to a manual edge labelling. [ABSTRACT FROM AUTHOR]

Concentrating solar power (CSP) mirrors must have high optical accuracy to achieve desired performance, which drives a need for accurate metrology systems. One approach to mirror metrology is to provide an optical target of known geometry and view its reflection to assess the location of known features. Such systems require reliable feature recognition to establish the correspondence between the target object and reflected image. Meanwhile, reflections in CSP mirrors exhibit distortion due to mirror curvature and slope errors. At small magnitudes, these distortions are beneficial because they provide an indication of mirror surface shape. However, excessive distortion magnitudes can confound metrology systems by making feature recognition and correspondence difficult. In this paper we explore the phenomenon of reflected image distortions both empirically and analytically. We show experimental data where the same object seen reflected in the same mirror can exhibit small to gross distortion, merely by varying the image capture parameters of target-to-mirror and camera-to-mirror distance. We present an analytic model explaining this phenomenon and show how it explains the observed results. We then extend the model to derive an equation for metrology system sensitivity. [ABSTRACT FROM AUTHOR]

Large size mirrors can cover larger surfaces of Parabolic Trough Collectors (PTC) than the state-of-the-art glass mirrors. A "jumbo reflector" of approx. ∼6 m x 3 m size has not only the potential for reducing installation and labor costs, but also decreasing the material in the back structure of the PTC. Under this study, the potential cost savings of jumbo reflectors is investigated through Finite Element Analysis (FEA) and Raytracing simulation tools. Four different collector structures using jumbo reflector are investigated and compared to a EuroTrough like collector as a reference case. From each simulation case, slope deviations and optical efficiencies for 13 different tracking collector angles are computed. Finally, an economic assessment is carried out to quantify the benefits of the new technology. The large reduction of material in the collector back structure ensures a decrease of the Levelized Cost of Electricity (LCOE) between 1 and 3.2 %. Moreover, in two cases it is even possible to equalize or increase the optical efficiency and at the same time reduce the steel consumption. Further results demonstrate that for high steel prices, the LCOE difference compared to the reference case can exceed 4%. Finally, due to the large size, transportation costs may increase, but even then, the LCOE is reduced when using jumbo reflectors for all the cases investigated. [ABSTRACT FROM AUTHOR]

Primary mirrors play an essential role in concentrating solar thermal (CST) plants as their optical performance directly influences the overall efficiency of the plant as well as their durability will influence the complete lifetime of CST plants. Primary mirrors are exposed to a combination of environmental agents that provoke their degradation. The aim of this work is to study the degradation caused by ultraviolet (UV) radiation an. For this purpose, two commercial silvered-glass reflectors from two manufactures with different glass thickness have been subjected to accelerated aging tests. An additional 4-mm silvered-glass reflector with an abrasion resistant hard coating on non-solar glass was also tested. The measured degradation provoked by UV radiation showed to be temperature dependent causing enhanced degradation when both stresses acted simultaneously, just as the presence of an abrasion-resistant coating such as the one used in this work has shown to affect the behavior of reflectors. [ABSTRACT FROM AUTHOR]

To be able to function optimally, CSP technology requires a strong direct sunlight. This constraint limits the potential implantation areas to mainly arid environments, which in fact present particularly aggressive environmental conditions for the solar components. The limitation of CSP plants on arid areas constitute a very important risk because this type of environment is characterized by sandstorms occurrence, hard sand particles and high wind speeds which transport particles from the ground to the reflectors surface causing significant mechanical damages. Erosion is among the most frequent degradation phenomenon that damage the mirrors surface. This damage increases the diffuse reflectance rate and generates very important optical losses. In order to reduce erosion risk, anti-wear coatings are designed as a solution of erosion issues, to give a better mechanical hardness to the solar reflector and consequently a better lifetime. This work aims to study the mechanical resistance behavior over time of two types of glass solar mirror: uncoated and hard coated by real time outdoor exposure in two different sites: desertic and coastal. The optical and mechanical performances of tested samples was investigated. The results highlighted a very limited durability of hard-coated samples compared to uncoated samples due to the fast coating degradation. [ABSTRACT FROM AUTHOR]

This work presents the developments on high reflective and high durability silver mirrors combining magnetron sputtering layers with paint protective layers. The magnetron sputtering system was optimized. Firstly, the adhesion layer placed between the glass and the silver was studied. The very thin (< 4nm) conventional magnetron sputtering adhesion layers based on chromium compounds were substituted by a RF etching process. Secondly, the silver magnetron sputtering layers was optimized. A 170 nm magnetron sputtering silver layer was developed through optimizing all the sputtering parameters, including voltage, pressure, vacuum conditions, and target-to-substrate distance. The combination of all these factors made us to reach reflective values on second surface glass mirrors between 95.4% and 96% (±1%). Secondly, a multilayer system developed by magnetron sputtering was designed with the objective of protecting the silver layer and making it compatible with the painting protective layers. Several designs were analyzed by combined zirconium layers with silicon nitride layers and a copper layer. The optimum magnetron sputtering systems were painted with the three conventional polyurethane paints. The optimum results show high reflectance values combined with high durability. No degradation in the reflective values was observed after applying the damping heat test (UNE-EN ISO 6270-1:2002), the weather exposure test (ISO 6270-1:2002), the accelerated weather QUV test (ISO 11507:2007 method A) and neutral salt spray test (ISO 9227:2006 NSS). [ABSTRACT FROM AUTHOR]

TPS 31A beamline utilizing wiggler source W100 is designed for the application of projection X-ray microscopy (PXM) and transmission X-ray microscopy (TXM). The high flux of the wiggler source is benefit for the excellent temporal resolution of images. Nevertheless, the large heat load induces severe thermal-deformation and big slope error of the optics in consequence degrades the uniformity of the images seriously. The vertical collimating mirror (VCM) is the first optical element of this beamline, and the absorbed heat load will be up to 112 W. Its thermal deformations should be well-controlled for optimizing the energy resolution of the double crystal monochromator (DCM) and the image quality. Deliberately, top-side water cooling method was adopted to minimize the thermal deformation of the VCM. The thermal slope error in an optimized top-side water cooled VCM can be reaches less than 0.8 µrad of magnitude compared to a non-optimized VCM. [ABSTRACT FROM AUTHOR]

We live in a period of fourth industrial revolution also known as 4IR.4IR is considered as a combination of robotics, AI, quantum computing, IoT and other upcoming technologies. Smart apps are not only used on phones and computers but also many smart products are coming to market. In modern times, household appliances are smarter than in previous decades due to impressive technological advances, especially as IoT-based platforms where almost all electrical appliances are smarter than the previous generation. It will never end making a device 'smart' with the help of adequate technology. In this paper, the aim is to create an inexpensive smart screen system that can display details based on user preferences. In this paper, IoT, smart AI-based mirror will support users, get necessary daily updates about weather, date, time, calendar, and so on, depending on user preferences. In addition, the touch and face recognition method are also used with a smart mirror to make buildings more secure. [ABSTRACT FROM AUTHOR]

In recent periods, Aluminum mirrors have been gaining popularity among researchers. It has wide range of properties, including low cost, low density/high strength ratio, corrosion resistant nature, high machinability, high thermal conductivity, etc. It even replaces glass mirrors for numerous applications. It can have endless applications such as a mirror, starting from aerospace, medical, defence, and even household and consumer goods. The polishing of the mirrors is a concern over the period. This study suggests cost-effective method of nano-polishing of aluminum using conventional and readily available tools. This study took two identical jobs 140 mm diameter each CNC turned commercial grade aluminum surface for sanding operation. Finally, polishing was done by soft polishing pads with different abrasive compounds and slurry. Experiments were done separately on them, and their process parameters and results (in terms of flatness and surface roughness) were compared. On both the operations, the results were satisfactory. However, operation on the 2nd job showed a slightly lower Ra value of 12nm.indicating better surface. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to describe and explains about idea of an Artificial intelligence-based Smart mirror (A.I.S.M) which is a unique technology for a Perfect Smart home. It's not only for a home environment but we can customize for commercial uses in various industries. This smart mirror seems like a normal mirror but it has a display to show the details and a user interface with which the user can control all the smart appliances using their access and can control the appliances available at home, we can customize the interface based on the user needs. The AISM Consist of Raspberry Pi 4, ESP 8266 module, 18 inch LED Monitor, a 2way mirror sheet, Camera, Microphone and speakers.The AISM has features like face recognition and detect the user, Voice Recognition will recognise every member and interact with them with the help of Google Assistant, weather, online news feeds, date and time, Music entertainment, Social Media Notifications, E-Mail, connects IOT Based home appliances etc. The data's are stored in a cloud storage with the help of ESP node we can handle the home appliances in an easy manner. By the development of AISM we can make our life easier and time efficient. [ABSTRACT FROM AUTHOR]

Practically based on the results of bench tests, functional errors were obtained and presented when measuring the difference in heights and azimuths of two luminaries located on different almucanters, data for calibrating the azimuthal limb of a sextant with two degrees of freedom of a large mirror are given. The identified errors should be taken into account either as corrections to the measured height differences, or as additional functional calculations of the azimuth difference before applying the main algorithm for calculating the observed coordinates from the measured difference navigation parameters. [ABSTRACT FROM AUTHOR]

In this paper 16m2 paraboloidal dish is utilized to identify the thermal performance of the system for low and medium temperature applications, with the improved absorber material on the reflector dish surface. To identify thermal aspects, the experimental setup consists of paraboloidal reflector dish, receiver with 0.5m diameter, steam-water separator, electric calorimeter and condenser. The experimentation conducted during normal sunny days when the sky is clear with no clouds and radiation intensity above 550W/m2. The scheffler dish frame is made of mild steel and channel structure is of aluminium to withstand wind speed during the operating conditions. To fix the glass mirror on the support structure, an industrial adhesive and fasteners are used to ensure the perfect fixing of the mirror and after ensuring equinox position of the support structure. The glass is 100 mm X 100 mm in size for easy handling and fixing on the aluminium channel with the help of silicon paste. The glass was coated with 0.5mm thick aluminium reflector with reflectivity of 85%. The thermal efficiency obtained 56.38% when net incident beam radiation of 604W/m2. With the use of aluminium reflector on the surface of glass mirror, to enhances the performance of the system significantly. [ABSTRACT FROM AUTHOR]

We describe a technology that uses a computer-driven, active servo control to change the shape of a heliostat reflector, in order to keep an image of the solar disc focused on a fixed distant target. The heliostat reflector is made with glass mirrors bent and rigidly attached to a support frame to form an initial specific concave toroidal shape. The different toroidal shapes needed throughout the day to maintain focus, despite the changing angle of the sun, are obtained by bending the frame by means of a truss of stiffening struts behind it. The struts are connected in pairs to a central back structural node, which incorporates linear actuators to change the truss geometry. For a hexagonal reflector, a total of three linear actuators suffice to adjust the amplitudes of the three lowest order orthogonal bending modes of the frame, and thereby to obtain all the different toroidal shapes needed for accurate imaging through the day. A recently constructed 1.6 m2 hexagonal prototype with three actuators has demonstrated this concept by producing sharp solar images throughout the day at a 40 m distant target. The measured flux concentration ranges from 90% to 98% into a square target measuring only 1.44 times the ideal disc diameter. Active heliostats of this type open new possibilities for nighttime solar electricity generation and solar industrial process heat, allowing fields of even relatively small numbers of heliostats to generate higher than current concentrations, as needed for high temperatures and more efficient energy conversion. A design for a scaled up hexagonal heliostat with 48 m2 reflector surface with eight petal mirror segments has been optimized using ANSYS. A 440 m diameter field of 776 of these heliostats would yield 25 MWth at 1,500x concentration by area, averaged over a cylindrical central receiver 2.75 m in height and diameter. [ABSTRACT FROM AUTHOR]

One of the key challenges for the CSP industry is to offer high-performance solar mirrors lasting two or three decades, at the lowest cost. For CSP, the performance criteria must include a high solar reflectance (up to 90%) with high specular reflection, i.e. the solar flux must reflect with an acceptance angle as small as possible. In this study, we have compared the reflected power distribution (the acceptance angle) of different commercial solar mirrors: new, soiled or natural and artificially aged. The measurements were performed using VLABS setup, at the Fraunhofer Institute in Germany. The objective is to make sure that different levels of ageing or soiling on the mirrors do not alter the power distribution, depending on the aperture angle. We conclude that all mirrors tested are good candidates. The analyses show that soiling or ageing do not alter the size of the specular reflection spot. All degraded, soiled and/or aged mirrors are able to focus the sun light with the same concentration ratio than new mirrors. [ABSTRACT FROM AUTHOR]

Accelerated aging testing can be a useful tool to evaluate the durability of solar reflectors for CSP applications. The selection of suitable testing procedures and parameters is essential to be able to create viable results. Despite important research efforts in the past, there is still a lack of agreement on the selection of these tests for silvered-glass mirrors and only one standard was published so far. This standard presents a series of tests without acceptance criteria and still lacks a correlation to real outdoor results. In this paper a guideline is presented that helps to select tests and parameters for silvered- glass mirrors for different purposes. All parameters are determined based on the correlation of outdoor data and the respective accelerated test results for a variety of different materials. On one hand, it allows for quick and easy screening for degradation mechanisms and the direct comparison of the durability of different materials. On the other hand, more complex lifetime prediction procedures are presented that enable the estimation of the behavior of the reflector materials depending on the foreseen exposure site. Depending on defined maximum degradation by the user, acceptance criteria for the accelerated tests are proposed. The development of the guideline into an international standard within the IEC framework is ongoing. [ABSTRACT FROM AUTHOR]

Concentrated Solar Power (CSP) technology has known a huge evolution in the last decades. Reflector is one of the most strategic components in CSP plant and soiling is one of the most deleterious parameters that should deeply understood during the choice of the plant localization. The main aim of this analysis is to evaluate the impact of soiling on reflectors' reflectance in a mountain climate as Morocco is launching a new CSP plant in Midelt region (Middle Atlas mountain). Through this analysis, it is shown that correlation of climate parameters like precipitations and wind is the key to enhance the understanding of the behavior of soiling in a mountain region. Up to 57% reflectance loss is recorded during summer periods while not less than 10% reflectance is registered during all periods of analysis. [ABSTRACT FROM AUTHOR]

Power tower or central receiver systems use hundreds to ten thousands of two-axis tracking mirrors, so called heliostats, which reflect and focus the sunlight onto a receiver on top of a tower during the day. As basis for a well performing heliostat field, a single heliostat has to perform "correctly". In order to describe and measure the performance of a single heliostat, the SolarPACES Guideline for Heliostat Performance Testing has been developed by a group of R&D and industry experts during the last years. However, at the end, the performance of the whole field, which means the superposition and interaction of all heliostats determines the energy collected in the aperture of a solar central receiver. For that reason, a second guideline is currently outlined, the SolarPACES Guideline for Heliostat Field Performance Testing. Both guidelines aim to be commonly agreed protocols between R&D centers and industry in the field of heliostat performance testing. Recently, a third guideline activity has been started to improve and unify heliostat wind load design methods. The once finalized guidelines (or their concepts) should be included in international standards (e.g. IEC) and used by national organizations like DKE, AENOR, ASME, ASTM. This paper gives an update of the state of the three guidelines being developed in the SolarPACES task III-heliostat working group. [ABSTRACT FROM AUTHOR]

The control of the profile on the surface of heliostats is crucial because the mirror can be imperfectly manufactured, and the distribution of solar irradiation on the receiver is sensitive to the curvature of the surface of the heliostat. In practice, irregularities in the surface of the heliostat introduce aberrations that contribute to enlarge the spot on the receiver and the resulting energetic losses depend on the collection characteristics of the solar plant. Since the solar field can be formed by thousands of mirrors, it is essential to have a quick and economical control method to be used during manufacturing operations and successively also in the field during installation. The proposed method of optical control is based on techniques of image analysis. It assesses the heliostat surface quality by means of the examination of the acquired image in comparison with a reference image. This on-site optical control could be applied on various mirror types. The application of this profile control requires only a photographic camera and a screen with a calibrated pattern. The main advantages are ease of application, low-cost equipment, and simplicity of processing. [ABSTRACT FROM AUTHOR]

A method for evaluating the yearly performance of a solar concentrator is used. The simulation is carried on using the commercial forward ray-tracing tool TracePro in conjunction with MATLAB. Ray tracing methods are commonly used to evaluate a solar concentrator's performance; however, some implementations oversimplify the simulation process and only consider a small representative number of scenarios throughout the year. For example, summer and winter solstices for tracking studies or monthly averages for evaluating the system's annual average output. The present method considers a year-long simulation on an hourly basis using MATLAB to set up step-by-step simulation within TracePro via the Dynamic Data Exchange (DDE) protocol; for increased fidelity, hourly irradiance data from Meteonorm is also taken into account. Given a defined mirror configuration, different mirror geometries are evaluated to determine the cosine, shadows, blockage, and spillage losses to compare on annual overall performance. [ABSTRACT FROM AUTHOR]

The Coulomb shift in the mirror systems of α +14C in 18O and α+14O in 18Ne is investigated by applying the orthogonality condition model (OCM). The result of OCM predicts the reduction of the excitation energies of the higher O+ states in the proton-rich nucleus of 18Ne in comparison to the energies in the neutron-rich 18O nucleus. This reduced excitation energy is similar to the phenomenon known as the Thomas-Ehrman shift, which means the lower shift in the excitation energy of the s-wave single particle orbit around the 16O core. [ABSTRACT FROM AUTHOR]

Detection of viscosity of lubricating oil was successfully carried out using a fiber coupler and concave mirror (CM) as reflector based on displacement sensor. The detection mechanism is carried out by placing the lubricating oil as a propagating medium for the light that comes out and goes back into the sensor probe after it is reflected by the CM. Viscosity of the lubricating oil is detected with the peak voltage of the optical detector resulting from displacing probe sensor to the concave mirror. Lubricating oil viscosity worth 2.79-25.75 cP was detected with a resolution of 0.0429 cP. [ABSTRACT FROM AUTHOR]

An innovative plasma technology is being developed, which is capable of cleaning Concentrating Solar Power (CSP) mirrors without the use of water. This novel technology also has additional benefits, which includes increasing the self-cleaning nature of the mirror surfaces and reducing surface soiling by modifying the surface energy of the collector mirrors. It is projected that this disruptive technology will save billions of litres of water per year, globally and will also increase the energy efficiency of the CSP power plants. [ABSTRACT FROM AUTHOR]

Mirror shape optimization is a major part of improving the performance of concentrating solar power (CSP) collectors. Loads and boundary conditions of different origin and with varying influence on shape deviation need to be understood and quantified, e.g., in order to give specifications for the design of new collector generations. Finite element analysis (FEA) has proven to be a suitable method for evaluating mirror shape. An optimization process is presented that utilizes finite element models (FEM) of mirrors and a subsequent evaluation of the slope deviation to approximate a reference, e.g., a measured mirror shape, and determine the load values causing the mirror panel to deform. In this paper, the suggested approach is proven to be feasible: Two optimization algorithms are implemented: BOBYQA and CMA-ES. A simulated reference created in ANSYS Workbench and a reference from a deflectometry measurement are investigated. The determined geometrical parameters are compared to the reference values. For BOBYQA an absolute minimum and maximum deviation of 0.02 % and 0.3 %, and for CMA-ES of 0.0001 % and 0.004 % relative to the reference values is found. With the measured mirror shape as reference, the optimization algorithm was again capable of reproducing the mirror shape in FEA. However, the geometrical load parameters found were only partially in agreement with the measured values. Yet, it is concluded that the proposed method for reproducing mirror shape works. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the erosion resistance of coated solar glass mirrors compared to a solar mirror with a blank surface. The evaluated coatings are a hard and an antisoiling coating. The study is conducted to understand the limits and the advantages of modifying surfaces by coating adding on the initial reflectance of the glass mirrors and also on their resistance towards degradation under harsh conditions. The experimental erosion simulations are conducted on a horizontal test bench propelling a rate of sand particles on the target surfaces with different test conditions (air velocity and impact angle). The obtained results have showed a good resistance of the hard coatings samples towards erosion compared to the blank surface and the antisoiling coating. The resistance of the hard coated samples is reflected by a minor degradation of optical properties (specular and hemispherical reflectance) in the extreme test conditions and by a surface degradation less important compared to the tested materials, namely, roughness modification and impacts properties. [ABSTRACT FROM AUTHOR]

This paper reviews the effect of weather parameters on natural degradation of solar reflectors mirrors exposed in Morocco. Outdoor aging tests of four types of solar glass mirrors and two polymeric reflectors have conducted in two different Moroccan sites (desert and sea side sites) for about 3 years. The neural network modeling approach was adopted to model the effect of weather factors on mirrors degradation. The measurements of meteorological and environmental factors formed the neural network inputs while mirrors degradation (loss of reflectance, corrosion rate, backside paint yellowness) measured during the exposure test forms the model output. This paper focus on modeling results obtained for reflectance loss due to dust deposition phenomenon. [ABSTRACT FROM AUTHOR]

During the life time of Concentrated Solar Power (CSP) plants, optical performance of solar mirrors is affected by soiling phenomena and surface degradation. It is imperative to dissociate soiling that requires cleaning from irreversible degradations which affect the plant performance. In both cases, small degradations or dust deposition cause an optical reflectance loss. In order to provide an adequate cleaning strategy, operators need to determine soiling-induced performance loss. Several commercial instruments already exist to measure optical reflectance, but they are dedicated to a single wavelength range or angle, punctual measurements or to laboratory analyses. CEA has developed a new kind of laboratory sensor to measure separately the loss of reflectance due to the degradation and soiling, thanks to a CCD camera and photodiodes. This equipment allows addressing variable wavelength, incidence and acceptance angles, to compare specular and hemispherical reflectance from other devices. The analysis of the images will quantify the soiling rate in order to optimize the frequency of cleaning water operations. The aim of the present contribution is to distinguish soiling from degradations (abrasion or corrosion of the reflective layer). This paper reviews the different current research works on prototype instruments and a comparison of this new alternative instrument with available commercial ones. [ABSTRACT FROM AUTHOR]

The upgraded version of the Tracking Cleanliness Sensor, the so-called TraCS4, which determines the real- time cleanliness and soiling rate of four mirror samples simultaneously is presented. Using this device, different materials can be intercompared at the site of interest which is the main advantage as the performance of anti-soiling-coatings is usually dependent on local weather conditions. A detailed uncertainty analysis of the TraCS4 device results in a cleanliness measurement uncertainty of about 0.019 cleanliness points. The uncertainty for the intercomparison of different materials is derived to be 0.012 cleanliness points. Exemplary soiling measurements with different anti-soiling and reference coatings at PSA are presented. [ABSTRACT FROM AUTHOR]

This paper presents an indirect method to estimate the near-normal sun-conic reflectance of solar mirrors, which is considered to be the relevant parameter to describe the reflectance characteristics of reflectors employed for CSP systems. The indirect method has been validated by direct measurements with the Spectral Specular Reflectometer measurement device reported in previous conferences. Good agreement between indirect and direct measurements was found for new and aged mirrors but not for soiled mirrors, where different phenomena seem to occur. The indirect method is thus only applicable for clean mirror surfaces in new and aged condition. The benefit of the indirect method is that it is simple and applicable with commercial equipment, providing a useful tool to determine near-normal sun-conic reflectance for all laboratories which do not own advanced reflectometers. [ABSTRACT FROM AUTHOR]

Composite mirrors formed of a self-supporting structure with a thin glass mirror can have advantages in comparison with traditionally used solar mirrors used in Concentrating Solar Power (CSP) applications. The intrinsic stiffness and the reduced glass thickness can allow for cost savings in the structure of a concentrator/collector and lead to increase of reflectance due to reduced losses in the glass. However, the combination of different materials may lead to mechanical stresses due to the behavior under variable temperatures or temperature distributions. Mechanical stress can lead to a deformation of the reflector surface and hence may influence the concentrator performance. As a first approach to emulate deformations of composite mirrors in the field, we assessed deformations due to temperature changes both through simulations and experimentally. The latter was possible by extensive adaptions of our measurement system. We combined a deflectometry measurement system and a chamber with tempered circulating air. The measurements were accompanied by Finite Element Method (FEM) simulations of a composite reflector model. The experimental results show the large influence that the temperature has on the reflectors reaching maximum 0.3 mm deformation, consequently this leads to paraboloid deformations and, in most of the cases, reduction in focal length of the facets with increasing temperature ranging between 143 m to 63 m, matching well with the FEM simulations. [ABSTRACT FROM AUTHOR]

Daily reflectance measurements on mirrors used in CSP applications were obtained over a period of 4 months to monitor soiling as a function of meteorological and environmental parameters. The mirrors were placed at 45° increments from face down to face up, and the parameters monitored included temperature, relative humidity, wind speed, rainfall and particulate matter. In order to determine a relationship between the input parameters and the soiling, both multiple linear regression and artificial neural network models were employed. The feed-forward back-propagation neural network with two layers and 16 neurons per layer is the configuration that reaches the best predictive results without overfitting the data, reaching a correlation coefficient of 0.84, compared to a maximum correlation coefficient of 0.60 with the multiple linear regression allowing for quadratic interaction of terms. The model is used to predict the number of annual cleaning operations required for a CSP plant placed in a location with a similar climactic profile, in order to estimate the cleaning contribution to the annual operation and maintenance cost. [ABSTRACT FROM AUTHOR]

This paper presents the idea of securing the smart devices used at our home or work spaces. Smart mirrors are devices which are equipped with peripherals such as a one-way mirror placed on top of LED monitor, Raspberry pi, Microphones and Speakers. Smart mirrors eliminate the need for checking our phones for latest news or updates. It provides the necessary information such as clock, calendar, news, weather reports. It displays all the notifications of our mobile devices which is connected via LAN. It interacts with the user through verbal commands and provides compliments as well. It has a web interface which can be used by the user/owner of the smart mirror to configure, start/stop the service. The data stored in the device is encrypted using 128-bit AES Algorithm. The encryption is done through a USB device which stores the 128-bit long key. [ABSTRACT FROM AUTHOR]

In the present paper, an attempt has been made to review the performance of various solar powered refrigeration system. The refrigeration is closely related to the demand for cooling commodities. Solar refrigeration is the best alternatives to address this issue and it may be accomplished by using one of the refrigeration system like vapour compression system, thermo electric refrigeration. The simulation model of photovoltaic thermal hybrid system has been created by using TRANSYS and the performance of 1.44kW photovoltaic thermal hybrid system has been evaluated. The results of solar PV have been improved by using plane mirror which was inexpensive and cost effective. The average performance indicator of SPV powered refrigerator i.e. COP varies from 2.02 to 2.41 and maximum value obtained by using Nano refrigerant. Majority of the studies carried out on 40L to 50L direct cool refrigerator [ABSTRACT FROM AUTHOR]

MEMS based actuator and scanning mirrors are device that steers and reflects incident light by angular rotation of the mirror itself. For single axis scanning, the mirror itself provides the required angular rotation, while most of the biaxial scanning micro mirrors have a gimbal configuration. Electrostatic actuation is commonly being used because of ease of fabrication and work on the principle of electrostatic forces between pairs of movable and fixed electrodes. Parallel plate type tip-tilt/scanning mirror is commonly being used for smaller mirror dimensions (up to 2mm). For larger mirror diameter (>2mm), the desired scan angle leads to large gap between the electrodes, which increases the driving voltage drastically and leads to bulky driver controller. Alignment between fingers is essential to avoid lateral instability causing an in-plane rotational pull-in during an actuation. To reduce the driving voltage, the straight torsion springs which connect the mirror to the gimbal are replaced by comb structures. It finds applications in optical MEMS (OMEMS) [1, 2], digital light projector, optical switch, adaptive optics, communications, signal sensing, and confocal microscopes. In this paper, design, simulation of electrostatic actuation based parallel plate comb type two axis tilt scanning micro mirror is described. The effect of comb structure on pull-down voltage and resonant frequency is studied. [ABSTRACT FROM AUTHOR]

A synchrotron beamline requires a set of reference values for calibration of photon beam energy, which are generally obtained from the absorption edges of different materials. However, due to oxidation and other chemical effects, these values are often different from the values of a pristine material. This makes the task of energy calibration difficult. In the present study, we have used a W/B4C multilayer for wavelength calibration for Soft x-ray reflectivity beamline (BL-03) at Indus-2. The structural parameters of the multilayer were obtained from Grazing Incidence X-ray Reflectivity (GIXRR) measurements. For energy calibration of soft x-ray beam, the reflectivity data at three different wavelengths were collected and analyzed to find correct wavelength values. The values so obtained were linearly interpolated to generate a curve for photon beam energy for 400-1500eV energy range. [ABSTRACT FROM AUTHOR]

At present, many urban elements have been used in the traditional urban areas, in order to increase the efficiency of the environmental and functional performance of these areas. These elements have varied between urban furniture (such as a water spray fan), water mirrors and modern infrastructure and sanitation services. This study aims to study the impact of the one of these elements that can be used in the target case study (traditional Mosul city) which is a water mirror. To achieve the objectives of this study, Solene-microclimate will be used. This study concludes that the water mirror as a new type of waterscape effect reducing the surface temperature which consequently affects the microclimate around it in the Mosul City in Iraq. [ABSTRACT FROM AUTHOR]

Ultrawideband (UWB) triplet and quadruplet pulses generation exploits nonlinear effect in semiconductor optical amplifier (SOA) in nonlinear loop mirror (NOLM) is investigated in this work. Two signals are transmitted through the SOA-NOLM simultaneously to create cross-phase modulation (XPM) effect. Firstly, the XPM causes the production of doublet which later combines for creation of triplet and quadruplet. This technique engages a proper tuning of optical delay and a selection of suitable power in all loops. Besides, injection current of the SOAs also governs the formation of these pulses. Although, frequency of the signals can be varied accordingly, the pulses are limited to certain adjustment that shifted its position in time domain. Furthermore, the set up can also be assessed for monocycle and doublet pulses by extracting the output at several positions. It can be concluded that the design may work as multiple pulses generation. All pulses are examined and compared with their electrical spectrum counterpart for validity of this approach. [ABSTRACT FROM AUTHOR]

This research focuses on developing a method of evaluation the effect of concentrator on the solar panel performance to get a higher power and optimum efficiency. Also the effect of temperature on the solar panel system with and without concentrator was studied. A Flat Mirror has been used as a Concentrator (FMC) for low cost and low control power consumption which was fixed to the solar panel module. FMC has been used to increase the incident irradiance on solar panel system by concentrating the sun light ray on it and then to improve the cell performance. A comparison is made between two PV solar panel systems with and without concentrator. The FMC consists of two flat mirrors made of glass, with dimensions (146cm × 68cm) enclosed by aluminum frame and connected at an angle 60 ° with a solar panel (147cm × 68cm) tilted at 45° from the horizon. The results indicated that when the concentrator is used with the solar panel the efficiency increased by a factor of (51%) to (64%) and the variation in efficiency (Δƞ) is (25.4%), the variation in maximum output power (ΔPm) is (17%) and all solar parameters increased. The temperature of the environment affected all solar panel characteristics especially the power, and efficiency affected strongly by high temperature. [ABSTRACT FROM AUTHOR]

Here we describe an optical concentrator system for CPV which uses a large dish reflector to concentrate sunlight and a small receiver with fly’s eye lens array to apportion the focused sunlight equally between many multi-junction cells. The small receiver is fan cooled. This architecture is aimed at a reduction in cost of complete CPV generating systems, which include dual axis tracking. In many CPV systems the light is evenly divided by identical Fresnel lenses facing the sun, and the cells are typically housed along with the lenses in modules, backed by large, passively cooled aluminum plates. The fly’s eye system advantages are that the weight, complexity and cost of the inherently large scale optical collection is reduced to just that of the 4 mm thick glass mirrors, and the small receiver packages are easier and less expensive to manufacture than large modules. A specific fly’s eye generator design using two large off-axis primary reflectors and nonobscuring receivers below the collection area has been described recently by Hyatt et al. [1], and the principles have been demonstrated in a prototype. Here we describe an alternative on-axis design optimized for greater uniformity of the light distributed to the cells, and excellent tolerance to mispointing. Ray tracing analysis shows deviations in uniformity of the full spectrum of sunlight distributed to the many cells of no more than 1% for sun mispointing angles of up to 0.5° and 80% of the maximum flux reaches the CPV cells when mispointing to +/- 0.9°. In this design, the central receiver blocks 4% of the entering sunlight, however, mechanical construction is simplified with a corresponding reduction in weight and cost. Also, not all the light blocked by the receiver is wasted, since it will be used to power the receiver’s cooling fan via a built-in small PV panel, eliminating parasitic power loss. [ABSTRACT FROM AUTHOR]

Charge Symmetry Breaking in Λ−hypernuclei is a subject that has been strongly debated since the 60’s, from both the experimental and the theoretical sides. It manifests experimentally in a difference between the Λ separation energies of mirror hypernuclei. For the s−shell this difference appears to be sizeable and can be reproduced only by sophisticated theoretical calculations; for the p−shell it suggests a much weaker effect. In this paper an experimental review is given, updated by the most recent results on s− and p−shell Λ−hypernuclei. [ABSTRACT FROM AUTHOR]

Soiling is a factor of major importance regarding any solar energy conversion technology, as in Photovoltaic (PV) panels and, namely, in concentrated solar power (CSP), since scattering due to particle deposition severely reduces the mirror’s reflectance. Concerned with this problem, a collaboration between the Renewable Energies Chair, University of Évora, Portugal and the Institut de Recherche en Energie Solaire et Energies Nouvelles, Morocco, was created to investigate and compare soiling in mirrors in both locations. This research enables the comparison between particle deposition effects in the two climates, crucial to implement mitigation measures. Southern Portugal and Northern Africa have considerable potential for future CSP installations, which makes this study relevant from an economical point of view, as it may influence the maintenance procedures and expected energy production of such CSP plants. [ABSTRACT FROM AUTHOR]

Mirror reflectivity losses due to soiling is a major limiting efficiency factor that should be taken into consideration during the operations of CSP power plants. For this reason, in this study we assessed the impact of soiling on the reflectivity losses of two different solar mirrors (aluminum and glass) installed at the site of Green Energy Park at Benguerir in the mid-south of Morocco for a period of more than 18 weeks. The loss of reflectivity was measured on a weekly cycle using a portable reflectometer. In addition, we have weighted the mirror samples before and after exposition in order to quantify the density of dust deposition. The obtained results show that aluminum was less affected by dust in comparison to the glass mirrors in term of reflectivity losses. Besides, some climatic parameters as the relative humidity and rainfall can have a significant impact on the soiling rate with different pattern for each mirror sample. [ABSTRACT FROM AUTHOR]

Marine environments are characterized by aggressive climate conditions that are suitable for materials durability testing especially for solar mirrors. In order to obtain real data and significant results of new solar mirrors durability in shorter time, outdoor ageing tests could be conducted in such high corrosive environment since it provokes faster degradation. This paper presents the results of the first year of natural exposure testing of different type of silvered glass mirrors at a marine site in Morocco. Many failure modes were observed and analyzed during this study. Corrosion is the predominant failure mode that occurs in all mirror samples and causes a significant loss of their reflectivity. The behavior of tested mirrors was found to be depending especially to the used paint system. [ABSTRACT FROM AUTHOR]