The subject of the performed experiments comprised standard XR 110 02, XR 110 04 nozzles, TT 110 02, TT 110 04 nozzles and AI 110 02, AI 110 04 air induction nozzles. The working speed of spraying was vp = 7 km/h. Each nozzle was tested at the following three levels of working pressures: p1 = 0.2 MPa, p2 = 0.4 MPa ad p3 = 0.6 MPa. The spray liquid was pure water at the temperature of 20°C. The plant coverage was determined: sk – spray coverage, nk – number of droplets per 1 cm2. The analysis of results of maize spraying showed that both standard nozzles and both TT nozzles achieved better results with number of droplets and degree of surface coverage for each of applied operating pressure. The lowest results from all examined kind of nozzles for number of droplets achieved injector nozzles (AI). For operating pressure 0.4 MPa nozzles fulfilled agrotechnical requirements for using insecticids, herbicides and fungicides.
The paper concerns the problem of treatment of the systematic effect as a part of the coverage interval associated with the measurement result. In this case the known systematic effect is not corrected for but instead is treated as an uncertainty component. This effect is characterized by two components: systematic and random. The systematic component is estimated by the bias and the random component is estimated by the uncertainty associated with the bias. Taking into consideration these two components, a random variable can be created with zero expectation and standard deviation calculated by randomizing the systematic effect. The method of randomization of the systematic effect is based on a flatten-Gaussian distribution. The standard uncertainty, being the basic parameter of the systematic effect, may be calculated with a simple mathematical formula. The presented evaluation of uncertainty is more rational than those with the use of other methods. It is useful in practical metrological applications.
The subject of the performed experiments comprised standard RSMM 110-02, RSMM 110-02 nozzles, AI 110-02, AI 110-02 air induction nozzles as well as AZMM 110-02, AZMM 110-03 low drift nozzles. The working speed during spraying was vp = 7 km/h. Each sprayer was tested at the following three levels of working pressures: p1 = 0.2 MPa, p2 = 0.4 MPa and p3 = 0.6 MPa. The spray liquid was pure water at the temperature of 20°C. The plant coverage was determined: sk – spray coverage, nk – number of droplets per 1 cm2 of the leaf.
In agriculture, the mixing of pesticides in tanks is a common practice. However, it is necessary to previse possible physical-chemical implications of this practice, which may affect the efficiency of the treatments performed. Therefore, the objective of this study was to evaluate the effects of the addition of acaricide to insecticidal spray mixtures on the formation of spray droplets and the interaction with citrus leaves. The experimental design was totally randomized, in a (2 × 3 + 1) factorial scheme for seven treatments. Factor A corresponded to the spray mixture used (isolate or in the mixture). Factor B corresponded to the insecticides tested (lambda-cyhalothrin + thiamethoxam, phosmet, and imidacloprid) and the control consisted of a spray mixture with spirodiclofen only. Nine replications were performed for characterization of the spray droplet size spectrum and four replications for the analysis of the surface tension and the contact angle. The mixture of pesticides showed positive results in terms of application safety. The addition of acaricide to insecticide spray mixtures reduced the surface tension and contact angle of droplets on the adaxial surface of orange leaves. There was an increment in volume median diameter (VMD), a significant reduction in the volume of droplets with drift-sensitive size and improvement in the uniformity of droplet size. Therefore, the addition of acaricide to an insecticide spray mixture positively influenced spray droplet formation and the interaction with citrus leaves providing better coverage and droplet size fractions with an appropriate size for safe and efficient application.
Usually, cellular networks are modeled by placing each tier (e.g macro, pico and relay nodes) deterministically on a grid. When calculating the metric performances such as coverage probability, these networks are idealized for not considering the interference. Overcoming such limitation by realistic models is much appreciated. This paper considered two- tier twohop cellular network, each tier is consisting of two-hop relay transmission, relay nodes are relaying the message to the users that are in the cell edge. In addition, the locations of the relays, base stations (BSs), and users nodes are modeled as a point process on the plane to study the two hop downlink performance. Then, we obtain a tractable model for the k-coverage probability for the heterogeneous network consisting of the two-tier network. Stochastic geometry and point process theory have deployed to investigate the proposed two-hop scheme. The obtained results demonstrate the effectiveness and analytical tractability to study the heterogeneous performance.
The study was conducted at the University of Nebraska Pesticide Application and Technology Laboratory in North Platte, Nebraska in July 2015. Two application volume rates (100 and 200 l · ha−1) and three nozzle types (XR, AIXR, TTI) were selected at two flow rates (0.8 and 1.6 l · min−1) and at a single application speed of 7.7 km · h−1. Each collector type [Mylar washed (MW), Mylar image analysis (MIA), water-sensitive paper (WSP), and Kromekote (KK)] was arranged in a randomized complete block design. Each nozzle treatment was replicated twice, providing six cards of each collector type for each nozzle treatment. A water + 0.4% v/v Rhodamine WT spray solution was applied, given the fluorescent and visible qualities of Rhodamine, which allows it to be applied over all the collector types. MW had the highest coverage at 18.3% across nozzle type, followed by WSP at 18%, KK at 12% and lastly by MIA at 4%. MW resulted in a 58% increase in coverage, WSP in a 56% increase, and KK only an increase of 39% when the volume rate was doubled from 100 l · ha−1 to 200 l · ha−1 across nozzle type. MW coverage was similar to KK for half of the nozzles (XR 11002, XR 11004, AIXR 11002). Droplet number density fixed effects were all significant for nozzle type and collector type (p < 0.001) as was the interaction of nozzle type and collector type (p < 0.001). Results from this study suggest a strong correlation to data produced with WSP and MW collectors, as there was full agreement between both types except for the TTI 11004. Using both collector types in the same study would allow for a visual understanding of the distribution of the spray, while also giving an idea of the concentration of that distribution.
An Internet application was developed to support the design process of the WLAN access network. The whole program was designed as a desktop application using the following languages: HTML, CSS and JavaScript. The main task of the application facilitates the planning process of the WLAN access network, including the location of multiple base stations. There is an example of using the program in the WLAN network planning process. The main purpose of this application as the ability to carry out network planning using multiple base stations and provide radio coverage for the entire area served by Wireless Internet Service Provider, is obtained.
An important element of Internet of Things systems (IoT) is wireless data transmission. Narrowband Internet of Things (NB-IoT) and LTE Cat M1 (LTE-M) are the new standards for such transmission intended for LTE cellular networks. Cellular network operators has recently launched such transmission. The article presents the results of measurements of NB-IoT transmission parameters in this network, inside the building and in open urban areas. The main features of the NBIoT system and measuring equipment are briefly discussed.
Improving application efficiency is crucial for both the economic and environmental aspects of plant protection. Mathematical models can help in understanding the relationships between spray application parameters and efficiency, and reducing the negative impact on the environment. The effect of nozzle type, spray pressure, driving speed and spray angle on spray coverage on an artificial plant was studied. Artificial intelligence techniques were used for modeling and the optimization of application process efficiency. The experiments showed a significant effect of droplet size on the percent area coverage of the sprayed surfaces. A high value of the vertical transverse approach surface coverage results from coarse droplets, high driving speed, and nozzles angled forward. Increasing the vertical transverse leaving surface coverage, as well as the coverage of the sum of all sprayed surfaces, requires fine droplets, low driving speed, and nozzles angled backwards. The maximum coverage of the upper level surface is obtained with coarse droplets, low driving speed, and a spray angle perpendicular to the direction of movement. The choice of appropriate nozzle type and spray pressure is an important aspect of chemical crop protection. Higher upper level surface coverage is obtained when single flat fan nozzles are used, while twin nozzles produce better coverage of vertical surfaces. Adequate neural models and evolutionary algorithms can be used for pesticide application process efficiency optimization.
The assassination of the Mayor of Gdańsk Paweł Adamowicz in Poland’s leading national newspapers, This article compares the coverage of the incident in six print dailies (Gazeta Wyborcza, Rzeczpospolita, Nasz Dziennik, Gazeta Polska Codziennie, and two tabloids Fakt and Super Express) over a period of two weeks (14–26/27 January). Their presentation of the story differed considerably. There were marked differences not only in the total amount of space the individual papers devoted to the Adamowicz’s murder and its fallout, but also the way they selected, described and interpreted various points, and sought to contextualize it by introducing additional themes.
In this paper, the recent ice regime variations in the Kara Sea have been described and quantified based on the high-resolution remote sensing database from 2003 to 2017. In general, the Kara Sea is fully covered with thicker sea ice in winter, but sea ice cover is continuously declining during the summer. The year 2003 was the year with the most severe ice conditions, while 2012 and 2016 were the least severe. The extensive sea ice begins to break up before May and becomes completely frozen at the end of December again. The duration of ice melting is approximately twice than that of the freezing. Since 2007, the minimum ice coverage has always been below 5%, resulting in wide open-waters in summer. Furthermore, the relevant local driving factors of external atmospheric forcing on ice conditions have been quantitatively calculated and analyzed. Winter accumulated surface air temperature has been playing a primary role on the ice concentration and thickness condition in winter and determining ice coverage index in the following melt-freeze stage. Correlation coefficients between winter accumulated temperature and ice thickness anomaly index, the ice coverage anomaly index, duration of melt-freeze stage can approach -0.72, -0.83 and 0.80, respectively. In summer, meridional winds contribute closely to summer ice coverage anomaly index, with correlation coefficient exceeding 0.80 since 2007 and 0.90 since 2010.