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Number of results: 17
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Abstract

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.

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Authors and Affiliations

Andrzej Gajtkowski
Paulina Migdalska-Kustosik
Witold Bzdęga
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Abstract

With widespread use of pesticides in modern agriculture, the impacts of spray drift have become a topic of considerable interest. The drifting of sprays is a highly complex process influenced by many factors. The paper presents results of experimental research on a drifting cloud of droplets dispersing from aircraft. Experiments were conducted to quantify spray drift from aerial applications of pesticide. Parallel to the blowing wind, the measurement line 800 m long was disposed. The relationships between the relative dose and the distance of drift as well as spray density and its structure on the measuring length have been established.

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Authors and Affiliations

Tomasz Seredyn
Robert Rowiński
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Abstract

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.

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Authors and Affiliations

Andrzej Gajtkowski
Witold Bzdęga
Paulina Migdalska
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Abstract

This paper presents a multivariate regression predictive model of drift on the Coordinate Measuring Machine (CMM) behaviour. Evaluation tests on a CMM with a multi-step gauge were carried out following an extended version of an ISO evaluation procedure with a periodicity of at least once a week and during more than five months. This test procedure consists in measuring the gauge for several range volumes, spatial locations, distances and repetitions. The procedure, environment conditions and even the gauge have been kept invariables, so a massive measurement dataset was collected over time under high repeatability conditions. A multivariate regression analysis has revealed the main parameters that could affect the CMM behaviour, and then detected a trend on the CMM performance drift. A performance model that considers both the size of the measured dimension and the elapsed time since the last CMM calibration has been developed. This model can predict the CMM performance and measurement reliability over time and also can estimate an optimized period between calibrations for a specific measurement length or accuracy level.
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Authors and Affiliations

Eduardo Cuesta
Braulio Alvarez
Fernando Sanchez-Lasheras
Daniel Gonzalez-Madruga
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Abstract

The article presents the most frequent surname in Lithuania — Kazlauskas. Referring to the article “Mysterious Lewandowski” by K. Skowronek (2000), an attempt has been made to account for this frequency in three various ways. First, the principles behind the quantitative structure of anthroponomasticons (Zipf’s law) and the loss of surnames (genetic drift) are discussed. Then the Slavic origin of the surname under consideration has been highlighted as a typical trait of the majority of surnames in Lithuania. In connection with this fact, it has been stressed that caution must be exercised in proposing a thesis on its origin as a translation from Lithuanian on a mass scale, since this thesis requires plentiful empirical evidence. Finally, the etymology of the name is analyzed. Morphologically it is a typical surname derived from a toponym. This supposition is additionally supported by the existence in Poland of numerous localities called Kozłów, Kozłowo or similar name; these in turn are most likely to have been derived from appellative-based personal names of their owners or inhabitants, such as Kozieł.

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Authors and Affiliations

Justyna B. Walkowiak
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Abstract

The MEMS inclinometer integrates a tri-axis accelerometer and a tri-axis gyroscope to solve the perceived dynamic inclinations through a complex data fusion algorithm, which has been widely used in the fields of industrial, aerospace, and monitoring. In order to ensure the validity of the measurement results of MEMS inclinometers, it is necessary to determine their dynamic performance parameters. This study proposes a conical motion-based MEMS inclinometer dynamic testing method, and the motion includes the classical conical motion, the attitude conical motion, and the dual-frequency conical motion. Both the frequency response and drift angle of MEMS inclinometers can be determined. Experimental results show that the conical motions can accelerate the angle drift of MEMS inclinometers, which makes them suitable for dynamic testing ofMEMSinclinometers. Additionally, the tilt sensitivity deviation of theMEMS inclinometer by the proposed method and the turntable-based method is less than 0.26 dB.We further provide the research for angle drift and provide discussion.
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Authors and Affiliations

Qihang Yang
1
Chenguang Cai
2
Ming Yang
3
Ming Kong
1
Zhihua Liu
2
Feng Liang
4

  1. College of Metrology and Measurement Engineering, China Jiliang University, Hangzhou 310018, China
  2. National Institute of Metrology of China, Beijing 100013, China
  3. College of Electrical Engineering, Guizhou University, Guiyang 550025, China
  4. Shenyang Aircraft Corporation, Shenyang 110031, China
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Abstract

Business processes are omnipresent in nowadays economy: companies operate repetitively to achieve their goals, e.g., deliver goods, complete orders. The business process model is the key to understanding, managing, controlling, and verifying the operations of a company. Modeling of business processes may be a legal requirement in some market segments, e.g., financial in the European Union, and a prerequisite for certification, e.g., of the ISO-9001 standard. However, business processes naturally evolve, and continuous model adaptation is essential for rapid spot and reaction to changes in the process. The main contribution of this work is the Continuous Inductive Miner (CIM) algorithm that discovers and continuously adapts the process tree, an established representation of the process model, using the batches of event logs of the business process. CIM joins the exclusive guarantees of its two batch predecessors, the Inductive Miner (IM) and the Inductive Miner – directlyfollows-based (IMd): perfectly fit and sound models, and single-pass event log processing, respectively. CIM offers much shorter computation times in the update scenario than IM and IMd. CIM employs statistical information to work around the need to remember event logs as IM does while ensuring the perfect fit, contrary to IMd.
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Authors and Affiliations

Tomasz P. Pawlak
1
ORCID: ORCID
Bartosz Górka
1

  1. Institute of Computing Science, Poznan University of Technology, Poland
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Abstract

Chlorophyll a content and the density and species composition of algae were determined in drifting sea ice north of the Elephant Island (between 54-56°W and 60°30'—61°00'S) at the end of October 1986. In yellow-brownish pieces of brash ice the amount of chlorophyll α was on average 203.5 ± 149.9 mg m-3 at the density of algal cells of 255.7+137.8-103 in cm3. In not visibly discoloured ice the respective values were about 80 times lower, and in surface water about 700 times lower. 69 algal taxa were recorded in the samples, almost all of which were diatoms. Nitzschia cylindrus dominated in all the samples. A comparison of species composition in the investigated habitats revealed that the highest species similarities occurred between samples collected in discoloured ice, lower in the uncoloured ice and the lowest ones in water.

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Authors and Affiliations

Ryszard Ligowski
Maciej Lipski
Krzysztof Zieliński
ORCID: ORCID
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Abstract

Thermal image drift is observed in prevalent industrial-level cameras because their optomechanical design is not optimised to reduce this phenomenon. In this paper, the effect of temperature on industrial-level cameras is investigated, focusing on the thermal image drift resulting from ambient temperature changes and warming-up process. Standard methods for reducing thermal image drift are reviewed, concentrating on the lack of repeatability aspect of this drift. Repeatable thermal image drift is crucial for applying a compensation model as random thermal deformations in sensors cannot be compensated. Moreover, the possible cause of this issue is explored, and novel optomechanical camera modifications are proposed that maintain the thermal degrees of freedom for the deforming sensor, limiting the lack of repeatability aspect of thermal image drift to a low level. The improvement is verified by conducting experiments using a specialised test stand equipped with an invar frame and thermal chamber. Considering the results from the application of the polynomial compensation model, the standard deviation of the central shifts of image drift is reduced by ×3.99, and the absolute range of image drift is reduced by ×2.53.
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Authors and Affiliations

Marcin Adamczyk
1
ORCID: ORCID
Kohei Nimura
1

  1. Warsaw University of Technology, Faculty of Mechatronics, Institute of Micromechanics and Photonics, ul. Andrzeja Boboli 8,02-525 Warsaw, Poland
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Abstract

The quality of wheat spraying obtained while applying drift guard Turbo TeeJet 11 O 02 VP nozzles was tested. A standard boom and a boom equipped with an air sleeve were applied. Krukowiak-Bravo sprayer was used to test the influence of the air flux. The coverage was estimated on water sensitive papers. The spray coverage of wheat with TT 11 O 02 VP nozzles was satisfactory, both in case of conventional and air assisted applications.
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Authors and Affiliations

Andrzej Gajtkowski
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Abstract

High temperature and high electric field applications in tantalum and niobium capacitors are limited by the mechanism of ion migration and field crystallization in a tantalum or niobium pentoxide insulating layer. The study of leakage current (DCL) variation in time as a result of increasing temperature and electric field might provide information about the physical mechanism of degradation. The experiments were performed on tantalum and niobium oxide capacitors at temperatures of about 125°C and applied voltages ranging up to rated voltages of 35 V and 16 V for tantalum and niobium oxide capacitors, respectively. Homogeneous distribution of oxygen vacancies acting as positive ions within the pentoxide layer was assumed before the experiments. DCL vs. time characteristics at a fixed temperature have several phases. At the beginning of ageing the DCL increases exponentially with time. In this period ions in the insulating layer are being moved in the electric field by drift only. Due to that the concentration of ions near the cathode increases producing a positively charged region near the cathode. The electric field near the cathode increases and the potential barrier between the cathode and insulating layer decreases which results in increasing DCL. However, redistribution of positive ions in the insulator layer leads to creation of a ion concentration gradient which results in a gradual increase of the ion diffusion current in the direction opposite to the ion drift current component. The equilibrium between the two for a given temperature and electric field results in saturation of the leakage current value. DCL vs. time characteristics are described by the exponential stretched law. We found that during the initial part of ageing an exponent n = 1 applies. That corresponds to the ion drift motion only. After long-time application of the electric field at a high temperature the DCL vs. time characteristics are described by the exponential stretched law with an exponent n = 0.5. Here, the equilibrium between the ion drift and diffusion is achieved. The process of leakage current degradation is therefore partially reversible. When the external electric field is lowered, or the samples are shortened, the leakage current for a given voltage decreases with time and the DCL vs. time characteristics are described by the exponential stretched law with an exponent n = 0.5, thus the ion redistribution by diffusion becomes dominant.

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Authors and Affiliations

Martin Kuparowitz
Lubomír Grmela
Vlasta Sedlakova
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Abstract

An active beam-pointing stabilization system has been developed for a high-power KrF laser system to eliminate the long-term drift of the directional change of the beam in order to have a stable focusing to a high intensity. The control of the beam direction was achieved by a motor-driven mirror activated by an electric signal obtained by monitoring the position of the focus of the output beam. Instead of large sized UV-sensitive position sensitive detectors a simple arrangement with scatter plates and photodiodes are used to measure the directionality of the beam. After the beam stabilization the long-term residual deviation of the laser shots is ~14 μrad, which is comparable to the shot-to-shot variation of the beam (~12 μrad). This deviation is small enough to keep the focal spot size in a micrometer range when tightly focusing the beam using off-axis parabolic mirrors.
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Authors and Affiliations

A. Barna
I. B. Földes
J. Bohus
S. Szatmári
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Abstract

The manufacturing and characterization of polymer nanocomposites is an active research trend nowadays. Nonetheless, statistical studies of polymer nanocomposites are not an easy task since they require several factors to consider, such as: large amount of samples manufactured from a standardized procedure and specialized equipment to address characterization tests in a repeatable fashion. In this manuscript, the experimental characterization of sensitivity, hysteresis error and drift error was carried out at multiple input voltages (����) for the following commercial brands of FSRs ( force sensing resistors): Interlink FSR402 and Peratech SP200-10 sensors. The quotient between the mean and the standard deviation was used to determine dispersion in the aforementioned metrics. It was found that a low mean value in an error metric is typically accompanied by a comparatively larger dispersion, and similarly, a large mean value for a given metric resulted in lower dispersion; this observation was held for both sensor brands under the entire range of input voltages. In regard to sensitivity, both sensors showed similar dispersion in sensitivity for the whole range of input voltages. Sensors’ characterization was carried out in a tailored test bench capable of handling up to 16 sensors simultaneously; this let us speed up the characterization process.
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Authors and Affiliations

Carlos Andrés Palacio Gómez
1
Leonel Paredes-Madrid
2
Andrés Orlando Garzon
2

  1. GIFAM Group, Universidad Antonio Nariño, Cra 7 No. 21-84, 150001 Tunja, Boyacá, Colombia
  2. Universidad Católica de Colombia, Faculty of Engineering, Carrera 13 # 47-30, Bogota, Colombia
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Abstract

Sand drifting on road networks in the region of the Lower Algerian Sahara is one of the main problems for the sector. Machines are repeatedly deployed to overcome this phenomenon. The long experience acquired while dealing with the removal of sand from roads pushed us to focus on obstacles called "Draas". The purpose of this study is to perform an optimization of these special protective structures called “Draas”, using a reduced physical model. Model tests were performed in flow channel. The principle of modeling the wind transport using a reduced model is to simulate the wind using a liquid stream while respecting the laws of hydraulic and sedimentological similarity. The results obtained are extrapolated to make a normal size prototype.

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Authors and Affiliations

A.K. Sebaa
M. Belhamra
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Abstract

The construction process of the tunnel ground deformation regularity of surrounding rock, stability, deformation control of tunnel surface based on the requirements, combined with the characteristics of shallow tunnel with large-span. Used three-dimensional numerical simulation software, established a dynamic tunnel analysis program to simulate the construction process of center cross-diagram method and double sidewall drift method. Based on the stratum deformation, supporting force and analysis of plastic zone distribution, comparative analysis of engineering adaptability of different construction methods from the construction process and construction mechanics, get optimization tunnel construction scheme.

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Authors and Affiliations

Jiao Pengfei
Xiao Zhang
Xinzhi Li
Bei Jiang
ORCID: ORCID
Bohong Liu
Haojie Zhang
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Abstract

The control of structural vibrations due to ground motion can be done by the installation of a passive, active, and hybrid base isolation system. The primary function of the base isolator is to support the superstructure and provide huge horizontal flexibility and a long period of vibration. In this paper, a special HRDB base isolator is made from natural rubber with special elastic property and hardness. This base isolator is designed to support gravity loads of two-story RC building. The experimental hysteresis loop of this isolator is validated with analytical modeling hysteresis loop using Hysteresis program. The Bouc hysteresis rule was chosen as a model the hysteresis loop, and it is similar to experimental hysteresis loops. Later, a single bay two-story RC frame with a base isolation system was modeled using Ruaumoko 2D program subjected to three levels of earthquake excitations. After analyzing this frame under the 1994 Pacoima Dam Earthquake, the 1995 Kobe Earthquake and the 1940 El-Centro 1940 Earthquake. The numerical results show that this isolator is quite efficient in reducing the damage of structural and non-structural elements of the structure through minimizing inter-story drift, lateral displacement, and story acceleration. Therefore, this special HRDB based isolator is recommended to be used for low rise and medium-rise building in seismic regions.

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Authors and Affiliations

Amir Mohammad Alizada
Nor Hayati Abdul Hamid
Pattrick Tiong Liq Yee

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