Results Of Measurements Research Articles

Экспериментальное определение внешних характеристик тяговых подстанций переменного тока для выбора параметров активных устройств системы тягового электроснабжения

Objective: to develop a method of experimental determination of external characteristics of alternating current traction substations for selection of parameters of active devices of traction power supply system. Methods: finding of equivalent currents of phases of a step-down transformer using the theory of linear electric circuits; statistical methods, including: construction and approximation of external characteristics of regression analysis methods, construction of theoretical and experimental law of distribution of equivalent current of traction load and determination of current quantile for a given confidence probability. Results: advantages and disadvantages of methods of simulation modeling of traction power supply system as applied to determination of parameters of active devices are shown, possibilities of experimental method are given. A detailed description of the conducted experiment is given, connection schemes of measuring devices and vector diagrams of currents and voltages are shown. The main stages of the proposed methodology for selecting the parameters of the booster transformer are outlined. Calculation formulas for determining the equivalent phase currents are presented, the external characteristic for the selected traction substation is constructed. The theoretical and experimental distribution law of the equivalent current of the traction load was constructed and the quantiles of the equivalent current were determined, which amounted to 400 A at a confidence level of 0.968. The maximum required value of volt additive for the selected traction substation and the law of volt additive voltage control for the booster transformer were determined. Practical importance: the proposed methodology of selecting the parameters of active devices of traction power supply system based on the experimental determination of external characteristics of traction substations will allow to determine more accurately the energy performance of booster transformers. It is supposed to improve the methodology by processing the results of synchronous measurements of currents and voltages at neighboring traction substations feeding the inter-substation zone. This will make it possible to expand the possibilities of application of active devices of the traction power supply system and improve the algorithms of booster transformer operation, including taking into account the operation of controlled reactive power compensation devices.

Perancangan Sistem Alarm Kebisingan untuk Kapal Penangkap Ikan Berbasis Arduino Uno dengan Sensor KY-037

Fishermen are highly susceptible to hearing impairment due to prolonged exposure to the high-intensity noise of boat engines. While numerous studies have investigated the noise intensity levels of boat engines, no research has been conducted on noise warning alarm systems for fishing boats. Therefore, this study aims to develop a sound noise alarm system based on Arduino Uno with a KY-037 sensor for fishing boats, which is expected to reduce the potential for hearing impairment among fishermen. This research employs a quantitative descriptive approach, with data collected through experimental methods and analyzed by comparing noise level data at various engine speeds. The results of the noise level measurements of boat engines at the Fish Landing Base (PPI) in Cikidang, Pangadaran Regency, indicate that the majority of fishermen are safe from hearing impairment due to engine noise, as most boats there are small, with a Gross Tonnage (GT) capacity of under 5 GT. The risk of hearing impairment emerges for boats with a capacity of 11 GT running at a maximum engine speed of 1600 rpm, producing noise levels up to 84 dB. Thus, it is recommended that crew members use earplugs.

Magnetic structures in R5Pt2In4 (R = Tb-Tm) investigated by neutron powder diffraction.

Results of the neutron powder diffraction measurements carried out for R5Pt2In4 (R = Tb-Tm) are reported. The compounds crystallize in an orthorhombic crystal structure of the Lu5Ni2In4-type with the rare earth atoms occupying three different sublattices. Neutron diffraction data reveal that at low temperatures the rare earth magnetic moments order below the critical temperature equal to 105, 93, 28, 12 and 3.8 K for R = Tb, Dy, Ho, Er and Tm, respectively. With decreasing temperature the rare earth magnetic moments at the 2a and 4g2 sites order first, while the moments at the 4g1 site order at lower temperatures. Ferrimagnetic order along the c axis, described by the propagation vector k1 = [0, 0, 0], develops in Tb5Pt2In4 below the Curie temperature (TC = 105 K). At lower temperatures, an antiferromagnetic component in the ab plane appears. The component is incommensurate with the crystal structure (k2 = [0, 0.66, ½]), but it turns into a commensurate one (k3 = [0, 0, ½]) with decreasing temperature. Antiferromagnetic order along the c axis, described by k4 = [½, 0, 0], is found in Dy5Pt2In4 below the Néel temperature (TN = 93 K). The k4-related component disappears below 80 K and the magnetic structure transforms into a ferro/ferrimagnetic one described by k1 = [0, 0, 0]. Further decrease in temperature leads to the appearance of an incommensurate antiferromagnetic component within the ab plane below 10 K (k2 = [0, 0.45, ½]), which finally turns into a commensurate one (k5 = [0, ½, ½]). In Ho5Pt2In4, a sine-modulated magnetic structure with moments parallel to the c axis (k6 = [⅓,0,0]) is observed below 28 K. With a decrease in temperature, new components, related to k1 = [0, 0, 0] (bc plane) and k4 = [½, 0, 0] (c axis), appear. The coexistence of two orderings - in the ab plane (k1 = [0, 0, 0]) and a modulated one with moments along the b axis (k7 = [kx, 0, 0]) - is found in Er5Pt2In4 below 12 K. Decreasing temperature leads to the order-order transformation of the k1-related component to another one with magnetic moments still constrained to the ab plane and preserved value of the propagation vector (i.e. k1 = [0, 0, 0]). Tm5Pt2In4 orders antiferromagnetically below TN = 3.8 K. Thulium magnetic moments lie in the ab plane, while the magnetic structure is described by k5 = [0, ½ , ½]. The direction of magnetic moments depends on the rare earth element involved and indicates an influence of single ion anisotropy resulting from interaction with the crystalline electric field.

Design of an electronic device in the STEAM context to relate results of physical measurements with sounds, and its analysis through science teachers' perception

This work presents the design and details of an electronic system that uses software and hardware aspects to generate sound frequencies associated with the measurement of physical phenomena, such as temperature or other. It has potential to create fun and motivation activities in the classroom, encouraging the students to think about the association between scientific and technological aspects. It is based on a STEAM (Science, Technology, Engineering, Arts, and Mathematics) approach where an Arduino processing board measures a physical phenomenon value with a sensor, computes a mathematical relationship to define an associated sound frequency, and next sends an output signal to excite a speaker. The proposed electronic system is simple, but this subject may not be very familiar to many science teachers and, therefore, this article explains it step by step to allow its effective understanding and later usage in the classroom. Furthermore, this article also presents a discussion with science teachers in order to analyze their perception when they are challenged to understand and analyze the proposed system under a teaching perspective, which emphasized concernments such as the lack of training and materials, but positively indicates the proposal is feasible and has a satisfactory teaching potential.

Magnetoelastic coupling for Fe–Ga thin films epitaxially grown on different substrates

This paper reports the systematic study on the structure, magnetic properties and magnetoelastic properties for the Fe100−x Ga x (001) thin films epitaxially grown on the different substrates of GaAs(001) and MgO(001) using the sputtering technique. The alloy composition dependence of effective magnetoelastic coupling coefficient B eff along the FeGa [110] direction indicated that the largest magnetoelastic coupling was obtained for the Fe–Ga layer with x = 30 grown on the MgO substrate, which was evaluated to be B eff = − 9.4 × 107 erg cm−3. Considering the results of structural analysis and magnetization measurement, the different crystallite sizes depending on the kind of substrate may give rise to the different magnetoelastic coupling strengths between the Fe–Ga layers on the MgO and the GaAs. The magnetostriction along the Fe–Ga [111] direction λ 111 was also estimated with the assumption of plausible elastic property of Fe–Ga, and showed the values comparable to the reported value of bulk Fe–Ga. This means the large magnetostriction can be obtained even for the Fe–Ga thin films epitaxially grown not only on the GaAs(001) but also on the MgO(001). The findings in this work will give a guideline for designing spintronic applications with a Fe–Ga layer exhibiting a large magnetoelastic coupling.

Robustness of the pyrochlore structure in rare-earth A2Ir2O7 iridates and pressure-induced structural transformation in IrO2

A comprehensive study of the structural properties of the heavily investigated rare-earth A2Ir2O7 iridate series under extreme conditions is presented. From Pr2Ir2O7 to Lu2Ir2O7, the series is sufficiently covered by iridates with A = Pr, Sm, Dy, Ho, Er, Tm, Yb, and Lu; general trends and systematics within the series, including the understudied heavy-rare-earth members, are dependably followed. Temperature- and pressure-dependent synchrotron X-ray powder diffraction experiments reveal robustness of the pyrochlore structure throughout the series, down to 4 K and up to 20 GPa. The thermal expansivity of the pyrochlore lattice is determined, all falling in the Debye temperature range of θD = 360–420 K. The pressure compressibility shows a systematic increase of the bulk modulus with the rare-earth atomic number from K = 180–210 GPa. Combining the results of thermal measurements (Debye temperature) and pressure measurements (bulk modulus) enables us to determine the Grüneisen parameter of selected members and compare it to previous studies. Temperature and pressure evolution of the fractional coordinate of oxygen at 48f Wyckoff position, the sole free fractional coordinate in the crystal structure, is investigated and discussed regarding the antiferromagnetic ordering of the Ir magnetic moments. In addition to results on A2Ir2O7 iridates, the temperature and pressure evolution of the crystal structure of an IrO2 minority phase is followed. The tetragonal rutile-type structure is stable down to the lowest temperature. However, an application of pressure of approximately 15 GPa induces a structural transition: The tetragonal structure is orthorhombically distorted. The orthorhombic structure is still not fully stabilised at 20 GPa, and further distortion of the lattice (or subsequent structural transformations) is expected with increasing external pressure.

ENGINEERING-GEODETIC SURVEYING. GEOMETRIC LEVELING OF THE ROUTE

The purpose of leveling the route is to determine the elevations of all the control points, including the beginning, middle, and end of curves, plus points, and points on transverse profiles. Longitudinal and transverse leveling is carried out after the route has been set out. The results of leveling (elevation measurements) are subsequently used for constructing the longitudinal profile of the route and the transverse profiles.The paper outlines the main principles and methods of leveling, taking leveling readings on rods, referencing the road route to benchmarks, leveling junction and intermediate points, balancing elevation differences, and calculating junction and intermediate points. The paper also describes the control of route leveling and plotting the projected line on the longitudinal profile.Engineering-geodetic surveying, specifically geometric leveling of the route, is an important component of educational geodetic practice. Geodetic practice for students is conducted according to the academic curriculum and serves as a continuation of the learning process in the field. It completes the theoretical course and is conducted according to the academic plan. During practical training, students acquire skills in working with geodetic instruments and processing the results of field measurements, becoming familiar with the main types of engineering-geodetic work during surveys and construction of engineering structures. Students are required to participate in all types of work, conduct the necessary measurements, and process them in the office. Practical training in geodetic practices provides students with hands-on experience in applying theoretical knowledge to real-world scenarios. Through fieldwork, students gain proficiency in using a variety of geodetic instruments such as levels, total stations, and GPS receivers. They learn how to set up and operate these instruments accurately to collect precise measurements of elevation and distance. Furthermore, students learn the importance of teamwork and collaboration during field surveys. Working together with peers, they divide tasks, communicate effectively, and problem-solve on-site challenges that may arise. These collaborative experiences not only enhance their technical skills but also cultivate essential soft skills such as leadership, communication, and adaptability.

Негативний диференціальний опір і спектральні характеристики вихідних та опромінених електронами (з Е = 2 МеВ) світлодіодів GaAs1-xPx

The electrophysical and radiation characteristics of the original and irradiated electrons with E = 2 MeV GaAsP light emitting diodes were studied. The results of measurements of current-current characteristics in the range of 77 - 300 K are given. In the range of 180 - 77 K, a region of negative differential resistance was detected. The main characteristic parameters of light emitting diodes radiation are determined. The consequences of the effect of radiation defects on the emissivity and quantum yield of the studied structures are discussed.

Simultaneous measurement of thickness and ultrasonic wave velocity using a combination of laser-generated multiple wave modes in the thermoelastic regime

ABSTRACT This paper introduces a reliable laser ultrasonic technique without damage to the surface in the thermoelastic regime that provides a one-side access method for simultaneously determining the thickness and ultrasonic wave velocity by employing multiple wave modes. Initially, this study determines the optimal separated distance between two laser beams to achieve an effective signal-to-noise ratio of the employed wave modes. Subsequently, a pre-established ratio of 0.95 for the velocity of skimming longitudinal waves and longitudinal waves enables the simultaneous calculation using a combination of the skimming longitudinal wave, reflected shear wave, and mode-converted longitudinal wave in a single measurement. Experiments were carried out on various plane plates made of aluminium alloy 6061, ranging in thickness from 4 to 20 mm, demonstrating a high accuracy in thickness measurement, with a maximum absolute error of 0.05 mm. Compare the results of ultrasonic wave velocity measurements with theoretical calculations, the maximum absolute error is 32 m/s and 80 m/s for longitudinal wave and shear wave, respectively.

Determination of Slope Safety Factor Based on Hoek & Brown Collapse Criteria on Ampera-Surumana Road Section

Introduction: One way to determine whether a slope is stable or not is by using the safety factor criterion. The method to determine the safety factor using the limit equilibrium method. Administratively the research area is located in the village of Salubomba, Central Banawa District, Donggala Regency, Central Sulawesi Province. The results of the study are also expected to be used as one of the basis for planning the design of stable slopes in the area Method: The methods used in this research were qualitative and quantitative. The process in this research was carried out with each method. The process of collecting secondary data and primary data is carried out by Geology and Geological Engineering methods both qualitatively and quantitatively. Results and Discussion: Observations in this study were made in the field in the form of observations of bridging on road slopes. The bruises in the study area are grouped on the basis of their shape and genetics. Through the results of observations and measurements on rock slopes at the research site. Based on data processing on the GEOSTUDIO 2018 R2 software application. Then, the value of the slope safety factor at observation station 1 is 2.316. Conclusion: Based on testing and analysis of the Hoek & Brown collapse criteria method, it can be concluded that the value of the slope safety factor at observation stations 1, 2, 3, 4, and 5 is 2.316; 2.029; 1.765; 1.658; 2.622 respectively. At station 4 the level of vulnerability is medium (Landslides can occur), at station 3 is at a low level of vulnerability (Landslides rarely occur), while at stations 1,2 and 5 are at a very low level of vulnerability (Landslides very rarely occur).

Influence of tin additions on the corrosion passivation of TiZrTa alloy in sodium chloride solutions

Abstract In this study, the fabrication of Ti-12%Zr-4%Ta-2%Sn alloy, Ti-12%Zr-4%Ta-4%Sn alloy, and Ti-12%Zr-4%Ta-6%Sn alloy using powder metallurgy fabrication technique has been carried out. The influence of Sn addition on the corrosion of these alloys after 30 min and 3 days in 3.5% NaCl solution using various techniques has been reported. The Nyquist spectra revealed that boosting Sn content from 2 to 4% and further to 6% increases the corrosion resistance of the alloy through increasing the diameter of the obtained semicircle. Bode spectra also elucidated that the increased percentage of Sn increases the values of the impedance of the interface |Z| and the maximum degree of the phase angle (Φ). It was indicated from the cyclic polarization curves that the increased Sn content increases the passivation of the alloy through decreasing its rate of corrosion and increasing its corrosion resistance. The measured current over time at −0.10 V showed that the alloy with low Sn content, 2%, records the highest currents, which pronouncedly decreases when Sn content increases to 4% and further to 6%. Prolonging the time of exposure from 30 min to 3 days greatly enhances the passivation of the TiZrTaSn alloys due to the formation of mixed oxides of TiO2, ZrO2, TaO2, and SnO2. The results of these electrochemical measurements were confirmed by the surface investigations carried out by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results collectively proved that the uniform corrosion remarkably decreases with the increase in the Sn% and that the pitting corrosion is not likely to take place.

Analysis of the possibilities of reducing the levels of residual stresses in casting produced from synthetic cast iron

In the production of castings, residual stresses arise in the cooling process, the level of which is often unknown. Their significance in engineering practice is very important because they are superposed on the stresses from the service load and are often the primary cause of material failure leading to failure of the equipment or structure. Their quantification using numerical simulations is rather difficult because many variables enter into the calculation simulating technological processes. Therefore, residual stress levels are most often determined in such cases by experimental measurement and, if possible, by monitoring and evaluating the history of parameter changes due to changes in the input parameters.In the present paper, the results of experimental measurements of residual stresses in synthetic cast iron castings are presented, where the effect of Ti microalloying on residual stress levels was assessed. Based on the comparison of the results obtained experimentally on castings made from grey cast iron, it can be concluded that the addition of Ti metal reduced the residual stress levels while maintaining the tensile strength and hardness HB.

Analisis Social Return on Invesment (SROI) Program TJSL PT PLN (PERSERO) UTP Sumbasel di Desa Sendang Baru Lampung

The TJSL (Social and Environmental Responsibility) program requires justification for success in each of the program interventions. The Social Return on Investment (SROI) analysis is one of the methods used to measure the program's impact by identifying four types of effects, namely social, economic, environmental, and quality of life for stakeholders. The program measured in this SROI analysis is the Electrifying Lifestyle Innovation Assistance Program (Energy Conversion) for developing MSMEs producing Ant Sugar in Sendang Baru Village, Central Lampung Regency, Lampung. The research method used in this research is mixed methods, combining qualitative and quantitative research. The technical data was collected through observation, in-depth interviews, focus group discussions (FGD), and documentation. The data sources used are divided into two categories, namely primary data and secondary data. The results of the impact measurement show that an investment of IDR 125,000,000 by PT PLN UIP Sumbagsel produced an impact of IDR 238,357,619, meaning that every 1 rupiah invested generated an effect or benefit of 1.91 rupiah. The distribution of the most significant impact variants is the economic aspect at 78 per cent, quality of life at 19 per cent, and social at 3 per cent. Meanwhile, the distribution of impacts among stakeholders is most extensive for training participants at 38.4 per cent, LPPM Bandar Lampung University at 33.7 per cent, Mitra Usaha Sejahtera Cooperative at 18.1 per cent, Sugar Semut Wana Hijau MSMEs at 8.2 per cent and PT PLN UIP Sumbagsel at 1.6 per cent.

On the accuracy of the gradient method for determining the mean integral refractive index of air for large-scale dimensional measurements

The results of the analysis of the accuracy capabilities of the gradient method for determining the mean integral value of the group refractive index of air along the path of the laser radiation propagating on the surface atmospheric layer are presented. The mean integral refractive index of air is used in precision laser ranging as a correction to the results of large-scale dimensional measurements, taking into account the difference between the speed of the laser radiation propagation in the atmosphere and the speed of light in vacuum. The performed analysis includes a critical review of publications underpinning this method, and the prospects for its use in high-precision laser measurements of horizontal baselines of up to 5 km long with an expanded uncertainty of less than or equal to 1 mm are considered. This method has been studied in the framework of the Project 18 SIB01 GeoMetre “Large-Scale Dimensional Measurements for Geodesy” executed in accordance with the European Metrology Programme for Innovation and Research (EMPIR).

Hybrid calibration method for a single camera stereo digital image correlation system

In single camera stereo digital image correlation systems, the existing calibration methods have problems with poor accuracy and violation of theoretical constraints, so we have proposed a hybrid calibration method. In this study, we first explain the principles of the existing single camera stereo measurement calibration methods. Then, on the basis of the classical camera calibration method combined with the characteristics of planar mirror reflection imaging, a hybrid calibration method is proposed that not only satisfies the constraints of the same intrinsic parameters but also has higher accuracy. Next, we complete the mathematical model of the hybrid calibration method and explain the specific calibration process. Finally, the experimental results of point distance reconstruction and static displacement measurement show that, compared with the existing calibration methods, the hybrid calibration method has lower error and higher reconstruction accuracy.

Electrical conductivity of potassium polyferrite doped with doubly charged cations

To clarify the charge compensation mechanism and the way of alloying additives placement, the authors synthesised samples of potassium βʺ-polyferrites with a wide range of mole fraction of introduced doubly charged cations. For these samples, the authors measured the electronic conductivity, cationic conductivity, and performed X-ray diffraction (XRD) analysis. The authors identified the charge compensation mechanism in potassium β″-polyferrite when doped with divalent ions of calcium, strontium, magnesium, and zinc. The charge compensation mechanisms differ depending on the radius of the introduced doubly charged ion. The results of cationic conductivity measurements of potassium β″-polyferrites show the mobility reduction of large calcium and strontium cations of potassium ions. Such additives are quite promising for improving the mechanical strength and thermal stability of the catalyst granules. They also increase the chemical stability of the contact granules. Corrosion resistance of pellets is a critical parameter. It determines the period of effective functioning of the catalyst. The data on electronic conductivity allow one to conclude that the introduction of Mg2+, Zn2+ cations sharply reduces the electron exchange in the structure of potassium β″-polyferrite. This should inevitably cause deactivation of the catalyst, while Ca2+ and Sr2+ ions do not reduce the electron transfer rate. Moreover, using the proposed approach will intensify the research process.

Assessment of Cavitation Activity by Cavitation Noise in Different Frequency Ranges

The results of testing the spectral-acoustic cavitometer with measurement modes that differ in the frequency ranges of integration of cavitation noise are presented. For each of the H1–H4 modes, the lower integration frequency fmin is 1, 70, 180 and 300 kHz, respectively. The upper frequency is the same for all modes and is fmax = 10 MHz. Piezoelectric waveguide sensors were used as a cavitation noise receivers. The distributions of cavitation activity in non-uniform ultrasonic fields were recorded: in the volume of the ultrasonic bath (f0 = 35 kHz) and in the field of the submersible emitter (f0 = 21 kHz). The frequency range of integration was varied by changing the lower bound. It has been established that a change in the integration range within a fairly wide range does not have a noticeable qualitative effect on the result of measurements of cavitation activity, only a multiple change in the readings occurs. This conclusion was confirmed using sensors that differ in their spectral characteristics.

PERHITUNGAN BEBAN KERJA OPERATOR LINI PERAKITAN KOMPRESOR TIPE SVC93E20PBE UNIT REFRIGERATOR R600A DI PT. PANASONIC MANUFACTURING INDONESIA

Panasonic Manufacturing Indonesia produces electronic equipment especially for the needs of ordinary consumers, business and industry such as refrigerators, ACs, water pumps, fans, washing machines and audio with problems with refrigerator and AC production units. The research was carried out on the SVC93E20PBE type compressor assembly line for the R600A refrigerator unit with the problem of operator workload being too high, above 100%. The research was conducted for 30 days on three compressor assembly line operators using the workload analysis method, with the aim of obtaining the productive percentage and workload level of operators on the SVC93E20PBE type compressor assembly line for the R600A refrigerator unit. Data was taken following a standard work sampling observation sheet, containing employee activities while working or unemployed with adjustments. The results of workload measurement using the workload analysis method showed that operator 1's workload was 133.63%, operator 2's workload was 133.62%, and operator 3's workload was 133.74%. Based on the description of the workload results for compressor assembly operators for the SVC93E20PBE type 600A refrigerator unit, the researcher proposes the addition of two operators to the compressor assembly line, a total of five operators with a workload for each operator of 80.198%.

Projection hypothesis in the setting for the quantum Jarzynski equality

Projective quantum measurement is a theoretically accepted process in modern quantum mechanics. However, its projection hypothesis is widely regarded as an experimentally established empirical law. In this paper, we combine a previous result regarding the realization of a Hamiltonian process of the projection hypothesis in projective quantum measurement, where the complete set of the orbital observables of the center of mass of a macroscopic quantum mechanical system is restricted to a set of mutually commuting classical observables, and a previous result regarding the work required for an event reading (i.e. the informatical process in projective quantum measurement). Then, a quantum thermodynamic scheme is proposed for experimentally testing these two mutually independent theoretical results of projective quantum measurement simultaneously.

Development of a 10 K automated sample exchange cryostat for SANS_CSNS

The Small-angle Neutron Spectrometer at China Spallation Neutron Source (SANS_CSNS) is a functional apparatus utilized for the examination of structures and inhomogeneities within the size range of 1 to 100 nm. The development of sample environments for in situ experiments at low temperatures at SANS_CSNS is urgent in order to address the increasing demands of users. The CSNS Sample Environment Group has successfully designed and constructed an automated sample exchange cryostat for SANS experiments, capable of operating in a temperature range of 10 ∼ 500 K. This cryostat has been specifically engineered to accommodate up to four samples simultaneously and exchange samples automatically in order to optimize the utilization of neutron beams by minimizing the downtime associated with manual sample handling. The results of simulation and temperature measurement proved that sample temperature could be accurately controlled from 10 K to 500 K through the incorporation of a 4 K GM cryocooler and a heater. Furthermore, neutron scattering studies conducted on SANS_CSNS proved that this cryostat exhibits commendable temperature control capabilities and minimal background interference. This automated sample exchange cryostat will be available to researchers of SANS_CSNS in the following user programs.