scholarly journals Automated Low-Cost LED-Based Sun Photometer for City Scale Distributed Measurements

2021 ◽  
Vol 13 (22) ◽  
pp. 4585
Author(s):  
Cristobal Garrido ◽  
Felipe Toledo ◽  
Marcos Diaz ◽  
Roberto Rondanelli

We propose a monochromatic low-cost automatic sun photometer (LoCo-ASP) to perform distributed aerosol optical depth (AOD) measurements at the city scale. This kind of network could fill the gap between current automatic ground instruments—with good temporal resolution and accuracy, but few devices per city and satellite products—with global coverage, but lower temporal resolution and accuracy-. As a first approach, we consider a single equivalent wavelength around 408 nm. The cost of materials for the instrument is around 220 dollars. Moreover, we propose a calibration transfer for a pattern instrument, and estimate the uncertainties for several units and due to the internal differences and the calibration process. We achieve a max MAE of 0.026 for 38 sensors at 408 nm compared with AERONET Cimel; a mean standard deviation of 0.0062 among our entire sensor for measurement and a calibration uncertainty of 0.01. Finally, we perform city-scale measurements to show the dynamics of AOD. Our instrument can measure unsupervised, with an expected error for AOD between 0.02 and 0.03.

2015 ◽  
Vol 825-826 ◽  
pp. 763-770 ◽  
Author(s):  
Stefan Junk ◽  
Rebecca Matt

Today, 3D-printing with polymer plaster composites is a common method in Additive Manufacturing. This technique has proven to be especially suitable for the production of presentation models, due to the low cost of materials and the possibility to produce color-models. But nowadays it requires refinishing through the manual application of a layer of resin. However, the strength of these printed components is very limited, as the applied resin only penetrates a thin edge layer on the surface. This paper develops a new infiltration technique that allows for a significant increase in the strength of the 3D-printed component. For this process, the components are first dehydrated in a controlled two-tier procedure, before they are then penetrated with high-strength resin. The infiltrate used in this process differs significantly from materials traditionally used for infiltration. The result is an almost complete penetration of the components with high-strength infiltrate. As the whole process is computer-integrated, the results are also easier to reproduce, compared to manual infiltration. On the basis of extensive material testing with different testing specimen and testing methods, it can be demonstrated that a significant increase in strength and hardness can be achieved. Finally, this paper also considers the cost and energy consumption of this new infiltration method. As a result of this new technology, the scope of applicability of 3D-printing can be extended to cases that require significantly more strength, like the production of tools for the shaping of metals or used for the molding of plastics. Furthermore, both the process itself and the parameters used are monitored and can be optimized to individual requirements and different fields of application.


Author(s):  
B.V. Gusev ◽  
V.D. Kudryavtseva ◽  
V.A. Potapova

The practice of using recycled concrete from the broken concrete of substandard reinforced concrete products can become widespread in practice. The undoubted relevance of this topic is explained by the program for the renovation of the housing stock in the city of Moscow, which provides for the demolition of 5-storey residential buildings until 2032. The problem of recycling and reuse of construction waste becomes obvious to improve the environmental situation, as well as to reduce the cost of materials in construction and preserve natural resources. The article deals with the nanostructuring of cement systems by means of introduction of ultra- and nanodispersed mineral additives. In this case, additional grinding of mineral additives is carried out in cavitation units. Nanostructuring provides the compaction of concrete structures and an increase in the strength properties of concrete.


RSC Advances ◽  
2017 ◽  
Vol 7 (37) ◽  
pp. 23176-23181 ◽  
Author(s):  
Yueqiang Yu ◽  
Yanling Guo ◽  
Ting Jiang ◽  
Kaiyi Jiang ◽  
Jian Li ◽  
...  

In order to recycle agricultural and forestry waste and reduce the cost of materials and energy consumption of the laser sintering process, herein, a sustainable and low-cost walnut shell/Co-PES composite (WSPC) is developed.


Open Physics ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 93-103
Author(s):  
Ernst Kussul ◽  
Tetyana Baydyk ◽  
Alberto Escalante Estrada ◽  
Maria Teresa Rodríguez González ◽  
Donald Wunsch II

Abstract Solar energy is one of the most promising types of renewable energy. Flat facet solar concentrators were proposed to decrease the cost of materials needed for production. They used small flat mirrors for approximation of parabolic dish surface. The first prototype of flat facet solar concentrators was made in Australia in 1982. Later various prototypes of flat facet solar concentrators were proposed. It was shown that the cost of materials for these prototypes is much lower than the material cost of conventional parabolic dish solar concentrators. To obtain the overall low cost of flat facet concentrators it is necessary to develop fully automated technology of manufacturing and assembling processes. Unfortunately, the design of known flat facet concentrators is too complex for automation process. At present we develop the automatic manufacturing and assembling system for flat facet solar concentrators. For this purpose, we propose the design of flat facet solar concentrator that is convenient for automatization. We describe this design in the paper. At present, almost all solar-energy plants in the world occupy specific areas that are not used for agricultural production. This leads to a competition between the solar-energy plants and agriculture production systems. To avoid this competition, it is possible to co-locate solar-energy devices in agricultural fields. The energy obtained via such co-location can be used for agricultural needs (e.g., water extraction for irrigation) and other purposes (e.g., sent to an electrical grid). In this study, we also describe the results of an investigation on co-location methods for the minimal loss of agricultural harvest too.


2021 ◽  
Vol 20 (6) ◽  
pp. 499-505
Author(s):  
D. F. Goncharenko ◽  
A. I. Aleinikova ◽  
S. V. Yesakova ◽  
R. I. Hudilin

The aim of the work is to develop a technology for the restoration of damaged sections of sewer collectors using clinker bricks. A significant part of such collectors in the Ukraine has completely exhausted their depreciation resource. For their construction, concrete and reinforced concrete were used, which are subject to destruction as a result of the influence of many factors and, above all, microbiological corrosion. Therefore, the selection of the optimal repair technology using corrosion-resistant clinker brick is relevant. The paper considers the problems of repair and reconstruction of worn-out collectors. Technical and technological solutions of an open method for their recovery using pneumatic formwork and corrosionresistant clinker brick are presented. The design of the collector lining structure has been carried out using the finite element method. To justify the feasibility of using the proposed technology, two options for restoring a worn-out collector have been considered: the “pipe-in-pipe” method and method developed by the authors using clinker bricks. The second option in terms of the cost of materials is almost four times more economical and more expedient than the first one (where polymer materials are used). The advantage of restoring circular sewer collectors by means of laying clinker bricks lies in the durability and resistance of this material (taking into account the anticorrosive composition of concrete) to the aggressive effects of the sewer environment. It should be noted that the application of the developed restoration technology is the most appropriate in conditions of sparse building or outside the city due to the significant volume of earthworks.


Author(s):  
Karan S Belsare ◽  
Gajanan D Patil

A low cost and reliable protection scheme has been designed for a three phase induction motor against unbalance voltages, under voltage, over voltage, short circuit and overheating protection. Taking the cost factor into consideration the design has been proposed using microcontroller Atmega32, MOSFETs, relays, small CTs and PTs. However the sensitivity of the protection scheme has been not compromised. The design has been tested online in the laboratory for small motors and the same can be implemented for larger motors by replacing the i-v converters and relays of suitable ratings.


2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.


Author(s):  
Emerson da Trindade Marcelino ◽  
Júlio Mannuel Tavares Diniz ◽  
ALVARO ROCHA ◽  
Eisenhawer de Moura Fernandes ◽  
Raimundo Duarte ◽  
...  

Author(s):  
Mirza Sangin Beg

The second part of the translation has three segments. The first is dedicated to the history of Delhi from the time of the Mahabharat to the periods of Anangpal Tomar to the Mughal Emperor Humayun as also Sher Shah, the Afghan ruler. In the second and third segments Mirza Sangin Beg adroitly navigates between twin centres of power in the city. He writes about Qila Mubarak, or the Red Fort, and gives an account of the several buildings inside it and the cost of construction of the same. He ambles into the precincts and mentions the buildings constructed by Shahjahan and other rulers, associating them with some specific inmates of the fort and the functions performed within them. When the author takes a walk in the city of Shahjahanabad, he writes of numerous residents, habitations of rich, poor, and ordinary people, their mansions and localities, general and specialized bazars, the in different skills practised areas, places of worship and revelry, processions exemplifying popular culture and local traditions, and institutions that had a resonance in other cultures. The Berlin manuscript gives generous details of the officials of the English East India Company, both native and foreign, their professions, and work spaces. Mirza Sangin Beg addresses the issue of qaum most unselfconsciously and amorphously.


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