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Comparison of metering mechanisms of corn seed
Weirich Neto, Pedro H.;Justino, Altair;Namur, Rodrigo T.;Domingues, José;Garcia, Luiz C.;
Engenharia Agrícola , 2012, DOI: 10.1590/S0100-69162012000500017
Abstract: it was compared the performance of the metering mechanism of corn seeds (zea mays) in direct seeding in an area of ??200 ha, a property in piraí do sul, state of paraná - pr, in brazil. it was seeded 4 maize hybrids, 50 ha of each, with seeds of different sieves. the experiment was conducted in a randomized block design (rbd), with 3 treatments and 9 repetitions for each corn hybrid. the treatments were the pneumatic seed of metering mechanisms, horizontal perforated disc with and without ramp?. the plots were 40 m2 and were distributed at the early, middle and late sowing. the variables analyzed in each corn hybrid were initial population, faulty spacing, multiple spacing, acceptable spacing, and yield components. as there were no significant differences in the variables, it was concluded that the quality of seeding with different systems of distribution was similar in the different sieves of distributed corn seeds.
DREAM: DiffeRentially privatE smArt Metering  [PDF]
Gergely Acs,Claude Castelluccia
Computer Science , 2012,
Abstract: This paper presents a new privacy-preserving smart metering system. Our scheme is private under the differential privacy model and therefore provides strong and provable guarantees. With our scheme, an (electricity) supplier can periodically collect data from smart meters and derive aggregated statistics while learning only limited information about the activities of individual households. For example, a supplier cannot tell from a user's trace when he watched TV or turned on heating. Our scheme is simple, efficient and practical. Processing cost is very limited: smart meters only have to add noise to their data and encrypt the results with an efficient stream cipher.
F. Abramchuk,V. Manoуlo,M. Lipinskiy,A. Dziubenko
Аvtomob?lnyi Transport , 2010,
Abstract: Peculiarities of foreing gas electromagnetic metering valve construction and the principle of their functioning are presented. Their advantages and disadvantages are considered.
Intelligent Metering for Urban Water: A Review  [PDF]
Thomas Boyle,Damien Giurco,Pierre Mukheibir,Ariane Liu,Candice Moy,Stuart White,Rodney Stewart
Water , 2013, DOI: 10.3390/w5031052
Abstract: This paper reviews the drivers, development and global deployment of intelligent water metering in the urban context. Recognising that intelligent metering (or smart metering) has the potential to revolutionise customer engagement and management of urban water by utilities, this paper provides a summary of the knowledge-base for researchers and industry practitioners to ensure that the technology fosters sustainable urban water management. To date, roll-outs of intelligent metering have been driven by the desire for increased data regarding time of use and end-use (such as use by shower, toilet, garden, etc.) as well as by the ability of the technology to reduce labour costs for meter reading. Technology development in the water sector generally lags that seen in the electricity sector. In the coming decade, the deployment of intelligent water metering will transition from being predominantly “pilot or demonstration scale” with the occasional city-wide roll-out, to broader mainstream implementation. This means that issues which have hitherto received little focus must now be addressed, namely: the role of real-time data in customer engagement and demand management; data ownership, sharing and privacy; technical data management and infrastructure security, utility workforce skills; and costs and benefits of implementation.
Utilizing Vissim to Evaluate Ramp Metering Performance
International Journal of Traffic and Transportation Engineering , 2012, DOI: 10.5923/j.ijtte.20120101.01
Abstract: This paper provides an example of using microsimulation tools to examine the impact of using ramp metering on freeway performance. The well-known software package VISSIM has been utilized in this work to determine the effect of various parameters, such as volumes to capacity (v/c) ratio, detector location on the freeway, and the green times on ramp metering performance. The test network for this research is a microsimulation model for apart of Emirates Road, which is one of the major freeways in Dubai, United Arab Emirates (UAE). The basic model information was exported from the Dubai Strategic Planning Model R1000 (using VISUM software) to VISSIM (microsimulation software). The traffic conditions considered two different downstream conditions (with and without downstream bottleneck). The results showed that the application of ramp metering has a significant positive effect on freeway performance, when the traffic volume levels are moderate to high. On the other hand, the ramp metering application showed a slight improvement under low or very heavy traffic volumes.
Performance evaluation of injection metering systems
Antuniassi, Ulisses R.;Miller, Paul;Paice, Mark;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2002, DOI: 10.1590/S1415-43662002000100028
Abstract: a method for measuring the performance of agricultural injection metering systems was developed and used to assess the characteristics of three commercial system designs. steady-state characteristics were measured using both colored dyes and salt as tracers. dynamic response characteristics were determined by measuring salt concentration downstream of the injection point by monitoring electrical conductivity of the spray solution. salt added to a viscous test liquid changed viscosity slightly only at low shear rates and it is concluded that this liquid is appropriate for use in evaluation tests with injection systems. results from tests with 2 systems specifically designed for operation with agricultural sprayers gave a linear response with both water and the viscous test liquids and no evidence of dose pulsation in the delivered spray liquid. a system using a single-acting water driven piston had a performance that was dependent upon viscosity and that gave substantial dose pulsation. when injecting on the pressure side of the pump, response times for both increasing and decreasing dose levels were in the order of 3.2 s. when injecting on the input side of the pump, response times were greater and very dependant upon the total flow rate of the delivery system.
Normal probability plots for evaluation of seeds distribution mechanisms in seeders Gráficos de probabilidade normal para avalia o de mecanismos de distribui o de sementes em semeadoras  [cached]
Daniel Albiero,Antonio José da Silva Maciel,Kleber Pereira Lan?as,Leonardo de Almeida Monteiro
Semina : Ciências Agrárias , 2012,
Abstract: Currently great emphasis is given for seed metering that assist rigorous demands in relation to longitudinal distribution of seeds, as well as to the index of fails in spacing laws, breaks and double seeds. The evaluation of these variable demands much time and work of attainment of data and processing. The objective of this work went propose to use of graphs of normal probability, facilitating the treatment of the data and decreasing the time of processing. The evaluation methodology consists in the counting of broken seeds, fail spacing and double seeds through the measure of the spacing among seeds, preliminary experiments through combinations of treatments had been carried through whose factors of variation were the level of the reservoir of seeds, the leveling of the seed metering, the speed of displacement and dosage of seeds. The evaluation was carried through in two parts, first through preliminary experiments for elaboration of the graphs of normal probability and later in experiments with bigger sampling for evaluation of the influence of the factors most important. It was done the evaluation of seed metering of rotating internal ring, and the amount of necessary data for the evaluation was very decreased through of the graphs of normal probability that facilitated to prioritize only the significant factors. The dosage of seeds was factor that more important because factor (D) have greater significance. Atualmente grande ênfase é dada para mecanismos dosadores de sementes, que devem atender exigências cada vez maiores em rela o à qualidade de distribui o longitudinal, principalmente em rela o ao índice de falhas, quebras e duplas. A avalia o destas variáveis demanda muito tempo e trabalho, tanto para obten o de dados como para processamento. O objetivo deste trabalho foi propor a utiliza o de gráficos de probabilidade normal para facilitar o tratamento dos dados relativos aos fatores que possivelmente influem na qualidade de distribui o e diminuir o tempo de processamento dos dados de distribui o das sementes em semeadoras. A metodologia de avalia o constitui-se na medida dos espa amentos entre sementes e contagem de sementes quebradas, espa amentos falhos e sementes duplas. Foram realizados experimentos por meio de combina es de tratamentos cujos fatores de varia o foram: o nível de sementes no reservatório, o nivelamento transversal da semeadora, a velocidade de deslocamento e a dosagem de sementes. Uma avalia o de semeadora provida de anel interno rotativo foi realizada em duas partes primeiramente com experimentos para constru
YoMo - The Arduino based Smart Metering Board  [PDF]
Christoph Klemenjak,Dominik Egarter,Wilfried Elmenreich
Computer Science , 2014,
Abstract: Smart meters are an enabling technology for many smart grid applications. This paper introduces a design for a low-cost smart meter system as well as the fundamentals of smart metering. The smart meter platform, provided as open hardware, is designed with a connector interface compatible to the Arduino platform, thus opening the possibilities for smart meters with flexible hardware and computation features, starting from low-cost 8 bit micro controllers up to powerful single board computers that can run Linux. The metering platform features a current transformer which allows a non-intrusive installation of the current measurement unit. The suggested design can switch loads, offers a variable sampling frequency, and provides measurement data such as active power, reactive and apparent power. Results indicate that measurement accuracy and resolution of the proposed metering platform are sufficient for a range of different applications and loads from a few watts up to five kilowatts.
Freeway ramp metering control made easy and efficient  [PDF]
Hassane Abouaissa,Michel Fliess,Violina Iordanova,Cédric Join
Mathematics , 2012,
Abstract: "Model-free" control and the related "intelligent" proportional-integral (PI) controllers are successfully applied to freeway ramp metering control. Implementing moreover the corresponding control strategy is straightforward. Numerical simulations on the other hand need the identification of quite complex quantities like the free flow sp\^eed and the critical density. This is achieved thanks to new estimation techniques where the differentiation of noisy signals plays a key r\^ole. Several excellent computer simulations are provided and analyzed.
Danos de Conotrachelus dubiae (Coleoptera: curculionidae) em frutos de camu-camu (Myrciaria dubia) na Amaz nia Central  [cached]
Ferreira Sidney Alberto do Nascimento,Gentil Daniel Felipe de Oliveira,Silva Neliton Marques da
Revista Brasileira de Fruticultura , 2003,
Abstract: No Brasil, a ocorrência de Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae) em camu-camu [Myrciaria dubia (H.B.K.) McVaugh, Myrtaceae] tinha sido constatada somente em popula es naturais. Relata-se sua ocorrência em um cultivo experimental, onde se avaliou os danos de C. dubiae em frutos de camu-camu, em diferentes graus de amadurecimento, entre 1999 e 2003. Os danos causados pela larva aumentaram com o amadurecimento dos frutos, havendo maior comprometimento da polpa do fruto (30 a 90%) do que das sementes (7%). A incidência desse inseto pode implicar em perdas quantitativas significativas na produ o de camu-camu.
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