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Abstract

The purpose of this paper is to depict the effect of diffusion and internal heat source on a two-temperature magneto-thermoelastic medium. The effect of magnetic field on two-temperature thermoelastic medium within the three-phase-lag model and Green-Naghdi theory without energy dissipation i discussed. The analytical method used to obtain the formula of the physical quantities is the normal mode analysis. Numerical results for the field quantities given in the physical domain are illustrated on the graphs. Comparisons are made with results of the two models with and without diffusion as well as the internal heat source and in the absence and presence of a magnetic field.
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Authors and Affiliations

Othman Mohamed I.
Said Samia M.
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Abstract

The purpose of this paper is to study the thermoviscoelastic interactions in a homogeneous, isotropic semi-infinite solid under two-temperature theory with heat source. The Kelvin-Voigt model of linear viscoelasticity which describes the viscoelastic nature of the material is used. The bounding plane surface of the medium is subjected to a non-Gaussian laser pulse. The generalized thermoelasticity theory with dual phase lags model is used to solve this problem. Laplace transform technique is used to obtain the general solution for a suitable set of boundary conditions. Some comparisons have been shown in figures to estimate the effects of the phase lags, viscosity, temperature discrepancy, laser-pulse and the laser intensity parameters on all the studied fields. A comparison was also made with the results obtained in the case of one temperature thermoelasticity theory.

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Authors and Affiliations

Mohamed I.A. Othman
Ahmed E.E. Abouelregal
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Abstract

Average duration of a thermal winter in Hornsund has been determined for 216 days. Average soil temperature at depth of 5 cm in winter is equal —9.8°C. During a spring that lasts 35 days only, soil temperatures at depth of 5 cm indicate distribution nearest to a normal one. Soil temperature distribution in winter substantially differs from the one in spring.

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Authors and Affiliations

Mirosław Miętus
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Abstract

On the ground of continuous records of air and soil temperature at standard levels, changes of soil temperature against changes of air temperature have been analyzed at thick and without snow cover. The first example concerns a six-day winter thaw, and the second one a four-day autumn cooling. A particular influence of energy advection has been noted. A delay of changes of soil temperature was found to increase with depth in relation to air temperature. A hypothesis on correlation between air temperature at a height of 5 cm and soil temperature at a depth of 5 cm has been verified.

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Authors and Affiliations

Mirosław Miętus
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Abstract

Monthly and dekadal mean soil temperatures were evaluated with a use of measurements at depths of 5, 10, 20 and 50 cm, collected during the expeditions 1978—1986 and additionally at depths of 80 and 100 cm during the expeditions 1980—1986. Fourier analysis revealed a phase shift of 1 to 2 dekads between neighboring measurement depths.

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Authors and Affiliations

Mirosław Miętus
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Abstract

The paper presents the trends of air temperature of the Antarctic. In its elaboration 21 stations were taken into consideration carrying out temperature measurements in the years 1958–2000, and 34 stations in the years 1981–2000. After checking the homogeneity of the series by the Alexandersson’s (1986) test we found that at 16 stations the homogeneity has been broken. On the basis of the corrected measurement series we have determined the trends in air temperature. In the period 1958–2000 statistically significant (on 0.95 significance level) temperature increases occurred on the western coast of the Antarctic Peninsula (for example Faraday 0.67°C/10 years) and at the Belgrano and McMurdo stations. The greatest temperature rise was noted on the Antarctic Peninsula during the autumn-winter period. On the South Pole a negative trend in air temperature (–0.21°C) occurred, especially in the summer season. During recent years (1981-2000) significant changes took place in the air temperature tendencies in the Antarctic. In many regions of the Antarctic cooling began and on the cost of East Antarctica the temperature decreased by –0.82°C/10 years (Casey). In the interior of the continent also lower and lower temperatures occurred (Amundsen-Scott –0.42°C/10 years, Dome C –0.71°C/10 years). The coast of the Weddell Sea is getting colder (Halley –1.13°C/10 years, Larsen Ice –0.89°C/10 years). An increase in temperature was observed in the interior of West Antarctica (Byrd 0.37°C/10 years). The warming rate of the climate became weaker on the Antarctic Peninsula (Faraday 0.56°C/10 years). The largest temperature changes occurred in the autumn-winter season when in the Antarctic Peninsula region the temperature increased, while in the interior and at the coast of East Antarctica temperatures fell considerably.

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Authors and Affiliations

Marek Kejna
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Abstract

Hot tearing is a casting defect responsible for external and internal cracks on casting products. This irregular undesired formation is often observed during solidification and freezing. The solidification of molten metal also causes thermal contraction and shrinkage, indicating the occurrence of hot tearing when the alloy is restrained by the mould design. The parameters affecting this process include the pouring and mould temperatures, the chemical composition of the alloy, and the mould shape. Also, the factors affecting hot tearing susceptibility include pouring and mould temperatures, the grain refiner, as well as pouring speed. There are many methods of measuring the level of susceptibility to hot tearing, one of which is the thermal contraction evaluation during metal solidification, observed in cast products through several mould types. This paper discusses the hot tearing overview, the effect of pouring temperature, mould temperature, grain refiner, pouring speed on hot tearing, the type of mould, and criterion for hot tear observation.
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Authors and Affiliations

Akhyar
1

  1. Department of Mechanical Engineering, Univeritas Syiah Kuala, Jl. Syech Aburrauf No.7, Darussalam, Banda Aceh, 23111, Indonesia
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Abstract

Different temperature sensors show different measurement values when excited by the same dynamic temperature source. Therefore, a method is needed to determine the difference between dynamic temperature measurements. This paper proposes a novelty approach to treating dynamic temperature measurements over a period of time as a temperature time series, and derives the formula for the distance between the measurement values using uniformsampling within the time series analysis. The similarity is defined in terms of distance to measure the difference. The distance measures were studied on the analog measurement datasets. The results show that the discrete Fréchet distance has stronger robustness and higher sensitivity. The two methods have also been applied to an experimental dataset. The experimental results also confirm that the discrete Fréchet distance performs better.
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Authors and Affiliations

Zhiwen Cui
1
Wenjun Li
1
Sisi Yu
1
Minjun Jin
1

  1. College of Metrological Technology and Engineering, China Jiliang University, Hangzhou 310018, China
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Abstract

A lot of heat will generate in mass concrete after pouring to form temperature cracks, which will reduce structural stiffness. This paper briefly introduces the principle of solid heat conduction and the cause of temperature crack formation and then used COMSOL software to simulate and analyze the mass concrete. The results showed that the simulation model had enough reliability to analyze the temperature change; the internal and external temperature of concrete rose first and then decreased; the formation of temperature crack was related to the internal and external temperature difference; the internal and external temperature difference was inversely proportional to the heat conductivity coefficient of concrete and directly proportional to the pouring temperature. Then, according to the analysis results, two measures were put forward to prevent temperature cracks in mass concrete: selecting concrete materials with high thermal conductivity, i.e., selecting coarse aggregate and fine aggregate with larger heat conductivity coefficient and reducing concrete pouring temperature, i.e., selecting cement with lower hydration heat, paying attention to temperature reduction in the process of concrete stirring, and reducing the amount of cement.

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Authors and Affiliations

L. Guo
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Abstract

The paper presents the test description and results of thermal bowing of RC beams exposed to non-uniform heating at high temperature. Bending of a non-uniformly heated element is caused by free thermal elongation of the material it is made of. The higher the temperature gradient, the greater the bending. In the case when an element is exposed to load and high temperature simultaneously, apart from free bending also deformation of the RC element may occur, which is caused by the decrease of the concrete or reinforcing steel mechanical properties. In order to examine the contribution of the deflection caused by thermal bowing to the total deformation of the bent element with a heated tension zone, an experimental study of freely heated (unloaded) beams was performed. RC beams were heated: (1) on three sides of the cross-section or (2) only on the bottom side. Deflection of elements loaded by a substitute temperature gradient was calculated using the Maxwell-Mohr formula. The test results show that deflection of freely heated RC beams (caused by the thermal bowing phenomenon) can be 10 to 20% of the total deflection of loaded RC beams with a heated tension zone.

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Authors and Affiliations

R. Kowalski
M. Głowacki
J. Wróblewska
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Abstract

The oxygen and chlorophyll a contents. pH, temperature and transparency were studied in Lake Rzuno in the period from June 1998 - September I 999. This lake has a very strong thermal stratification and weaker oxygenic stratification. The degree of surface water saturation with oxygen was rather small (max. 136%) but the oxygen conditions in the whole Lake Rzuno were good because the total lack of oxygen is noted only in summer and only below 20 m depth. Whereas during autumn and spring circulation the oxygen concentration reaches 5 mg O, drn' al the bottom. The correlation between visibility of Secchi disc and chlorophyll a concentration featured high correlation indicator (r = -0.87). The awerage water transparency, low oxygen deficit and small changes in water reaction show that this lake has moderate eutrophic character.
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Authors and Affiliations

Jan Trojanowski
Janusz Bruski
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Abstract

Effects of temperature variation on the performance of silicon heterojunction solar cells are studied using opto-electrical simulations. It is shown that the low-temperature cell efficiency is determined by the fill factor, while at high temperatures it depends on the open-circuit voltage. Simulations revealed that the low-temperature drop in the fill factor is caused by poor tunnelling, in particular at the ITO/p-a-Si:H heterojunction. The authors link this drop in fill factor to a low maximum-power-point voltage and show how poor tunnelling is reflected in the charge redistribution determining the device voltage. The effect of the contact work function on temperature behaviour of efficiency by varying the electron affinity of ITO layers has been demonstrated. It was also demonstrated that increasing the electron affinity of ITO on the p-side minimises the work function mismatch, leading to significant improvements in efficiency, especially at low temperatures, while optimisation on the n-side results in marginal improvements over the entire temperature range. In addition to the cumulative effects of the temperature-dependent parameters, their individual contributions to the efficiency were also investigated. Moreover, it was presented that the thermal energy (kT) determines the efficiency temperature behaviour, while other parameters play only a minor role. This paper shows how temperature variations affect device performance parameters.
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Authors and Affiliations

Jošt Balent
1
ORCID: ORCID
Marko Topič
1
ORCID: ORCID
Janez Krč
1
ORCID: ORCID

  1. University of Ljubljana, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
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Abstract

Over the South American sector of the Antarctic Ocean intensive cyclonal activity occurred in turn with meridional circulation, which was a more common feature of winter 1986 than it usually is. At the Arctowski Station strong temperature oscillations were observed during the austral winter from May to October. In the end of July the lowest temperature of this winter, — 32.3°C, was recorded. In the first half of the winter an easterly air flow prevailed and in the second part — the westerly one. Winds were strong and gusty. The highest speed reached 74 ms-1 . Snowfalls were abundant; depth of snow exceeded 100 cm.

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Authors and Affiliations

Dominik Kowalski
Danuta Wielbińska
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Abstract

In the summer of 1979, in South Spitsbergen investigations of the extreme temperatures of the ground surface were carried out. The investigations permitted the determination of the magnitude of the extreme temperatures of the ground surface and their relation to the air temperature. The spatial variability of the extreme temperatures of the ground surface was observed.

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Authors and Affiliations

Andrzej Kamiński
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Abstract

Rape is an important oil crop with a wide range of uses. Harvested rapeseed must be cleaned and dried before processing. The process of drying rapeseed as a small-seeded crop has its own specifics. One of the new drying methods is the use of microwave radiation, the disadvantage of which is uneven heating of the product. The purpose of this work was to study the modes of drying rapeseed by electromagnetic radiation in the ultra-high frequency range in combination with filtration. The indicators of the intensity of oilseed drying by infrared irradiation on the experimental stand were determined. The analysis of the conducted studies showed that the temperature of seeds at the maximum microwave power rises in general 1.5 to 1.8 times faster than at half the power. The higher the seed moisture content is, the higher the rate of temperature increase. After each blowing cycle, which lasted for five seconds, the temperature of the rapeseeds was set higher than the previous temperature, and after increasing the blowing time up to fifteen seconds, the temperature decreased by 8–12°C and cyclically stabilized. The applications of microwave drying represented in the paper are environmentally friendly, since the seeds do not come into direct contact with the products of gas combustion, which deteriorate its quality due to the possible penetration of carcinogenic components into the products. Experimental data was taken into account when developing the design of a small-sized grain dryer for farms, in which the drying process takes place without heating the air as a heat carrier.
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Authors and Affiliations

Valentyna Bandura
1
ORCID: ORCID
Igor Bezbah
2
ORCID: ORCID
Ihor Kupchuk
3
ORCID: ORCID
Larisa Fialkovska
4
ORCID: ORCID

  1. Educational and Scientific Institute of Continuing Education and Tourism, National University of Life and Environmental Sciences of Ukraine, Ukraine
  2. Department of Processes, Equipment and Energy Management, Оdesa National University of Technology, Ukraine
  3. Engineering and Technology Faculty, Vinnytsia National Agrarian University, Ukraine
  4. Faculty of Trade, Marketing and Service, Vinnytsia Trade and Economics Institute of the State Trade and Economics University, Ukraine
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Abstract

Lateritic nickel ore is used for producing of ferronickel. Nickel grade in ferronickel ranged from 20–40%. Ferronickel is commonly used to manufacture stainless steel. A new method that can increase the levels of nickel grade is selective reduction, which is a process to reduce the metal oxide to the metallic phase with the addition of additives. In this work, the selective reduction of limonitic nickel ore was carried out by add the 5 wt%, 10 wt%, and 15 wt% of reductant and the 10 wt% of sulfur as additive. The process of selective reduction is performed at temperatures of 950, 1050, and 1150°C with the duration of processs of 60, 90, and 120 minutes, followed by magnetic separation to separate between the concentrate and tailings. The characterization used AAS, XRD, and SEM-EDS for grade and recovery; phases transformation; and the microstructure analysis. The optimum of the grade and recovery of nickel was obtained at a temperature of 1050°C with the duration of process of 60 minutes and 5 wt% of reductant and 10 wt% of additive, which obtain 3.72 wt% and 95.67%. The metal grade and recovery was increase with the increasing of temperature reduction. Nevertheless, too long of the duration of process and too many reductant addition resulted in negative effect on selective reduction of lateritic nickel ore. Highest recovery could get more nickel in the process. And sulfur has the important rules when the selective reduction has been done on the increasing nickel content, the forming of FeS, and decreasing the grain size of ferronickel according to the microstructure in the SEM images around ~30 μm.
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Bibliography

Cao et al. 2010 – Cao, Z.C., Sun, T.C., Yang, H.F., Wang, J.J. and Wu, X.D. 2010. Recovery of iron and nickel from nickel laterite ore by direct reduction roasting and magnetic separation. Chinese Journal of Engineering 32(6), pp. 708–712, DOI: 10.13374/j.issn1001-053x.2010.06.004.
Dalvi et al. 2004 – Dalvi, A.D., Bacon, W.G. and Osborne R.C. 2004. The Past and The Future of Nickel Laterites. PDAC 2004 International Conference Trade Show and Investors Exchange, Toronto, Canada.
Elliot et al. 2015 – Elliot, R., Rodrigues, F., Pickles, C.A. and Peace, J. 2015. A two-stage process for upgrading thermal nickeliferous limonitic laterite ores. Canadian Metallurgical Quarterly 54(4), pp. 235–252, DOI: 10.1179/1879139515Y.0000000009.
Elliot et al. 2017 – Elliot, R., Pickles, C.A. and Peace, J. 2017. Ferronickel particle formation during the carbothermic reduction of a limonitic laterite ore. Minerals Engineering 100, pp. 166–176, DOI: 10.1016/j.mineng.2016.10.020.
Foster et al. 2016 – Foster, J., Pickles, C.A. and Elliot, R. 2016. Microwave carbhotematic reduction roasting of low-grade ore nickeliferous silicate laterite. Minerals Engineering 88, pp. 18–27, DOI: 10.1016/j.mineng.2015.09.005.
Jiang et al. 2013 – Jiang, M., Sun, T., Liu, Z., Kou, J., Liu, N. and Zhang, S. 2013. Mechanism of sodium sulfate in promoting the selective reduction of nickel laterite ore during reduction roasting process. International Journal of Mineral Processing 123, pp. 32–38, DOI: 10.1016/j.minpro.2013.04.005.
Li et al. 2012 – Li, G., Shi, T., Rao, M., Jiang, T. and Zhang, Y. 2012. Beneficiation of nickeliferous laterite by reduction roasting in the presence of sodium sulfate. Minerals Engineering 32, pp. 19–26, DOI: 10.1016/J.MINENG.2012.03.012.
Prasetyo, A.B. and Puguh. 2011. Increased levels of nickel (Ni) and iron (Fe) from laterite ore saprolite type low levels for raw materials containing nickel pig iron (NCPII/NPI). Met. Mag. 26, pp. 123–130.
Prasetyo, A.B. and Firdiyono, F.E. 2014. Reduction process optimization laterite ore limonite as raw materials type NPI (Nickel Pig Iron). Majalah Metalurgi 29(1), pp. 9–16.
Valix and Cheung. 2002. Effect of sulfur on the mineral phases of laterite ores at a high-temperature reduction. Minerals Engineering 15, pp. 523–530.
Wang et al. 2017 – Wang, Chu, Z., Liu, M., Wang, H., Zhao, W. and Gao, L. 2017. Preparing ferronickel alloy from low-grade laterite nickel ore reduction based on metallized-magnetic separation. Metals 7(8), pp. 313, DOI: 10.3390/met7080313.
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Authors and Affiliations

Fathan Bahfie
1
ORCID: ORCID
Achmad Shofi
2
Ulin Herlina
1
Anton S. Handoko
1
Nanda A. Septiana
3
Syafriadi Syafriadi
3
Suharto Suharto
1
Sudibyo Sudibyo
1
Suhartono Suhartono
4
Fajar Nurjaman
1

  1. Research Unit for Mineral Technology, National Research and Innovation Agency of Indonesia, Jalan Ir. Sutami Km 15 South Lampung, Lampung, Indonesia
  2. Agency for Rembang Regional Planning and Development, Rembang Local Government, Indonesia
  3. Department of Physic-University of Lampung,Jl. Prof. Dr. Ir. Sumantri Brojonegoro No. 1, Gedong Meneng, Kec. Rajabasa, Kota Bandar Lampung, Indonesia
  4. Chemical Engineering Department, University of Jenderal Achmad Yani, Jalan Terusan Jend. Sudirman, Cibeber, Kec. Cimahi Sel., Kota Cimahi, Jawa Barat, Indonesia
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Abstract

The paper presents the results of simulation tests of hydraulic resistance and temperature distribution of the prototype Stirling alpha engine supplied with waste heat. The following elements were analyzed: heater, regenerator and cooler. The engine uses compressed air as a working gas. Analyses were carried out for three working pressure values and different engine speeds. The work was carried out in order to optimize the configuration of the engine due to the minimization of hydraulic resistance, while maintaining the required thermal capacity of the device. Preliminary tests carried out on the real object allowed to determine boundary and initial conditions for simulation purposes. The simulation assumes that there is no heat exchange between the regenerator and the environment. The solid model used in simulation tests includes the following elements: supply channel, heater, regenerator, cooler, discharge channel. Due to the symmetrical structure of the analyzed elements, simulation tests were carried out using 1/6 of the volume of the system.

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Authors and Affiliations

Mariusz Furmanek
Jacek Kropiwnicki
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Abstract

The Stirling engine type alpha is composed of two cylinders (expansion space E and compression space C), regenerator that forms the space between the cylinders and the buffer space (under the pistons). Before the start-up and as a result of long-term operation, the average pressure in the working space (above the pistons) and in the buffer space is the same. However, in the initial phase of operation, the average pressure in the working space is different then the average pressure in the buffer space depending on the crankshaft starting position (starting angle). This, in turn, causes a large variation in the starting torque. An additional unfavorable factor caused by a large variation in the course of the indicated torque is the rotational speed variation and the formation of torsional vibrations in the drive system. After some time, depending on the quality of the engine piston sealing, the average pressure in the working and buffer space will equalize. The occurrence of the above-described phenomenon affects the selection of the starting electric motor, which can be significantly reduced, when the crankshaft starting position is optimized (the starting torque is several times greater than the average torque occurring in the generator operation mode). This paper presents the analysis of the impact of the crankshaft starting position on the course of the indicated torque and the resulting start-up energy. Starting the engine at an unfavorable position of the crankshaft may, in extreme cases, increase the starting torque even three times.

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Authors and Affiliations

Jacek Kropiwnicki
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Abstract

The Exodus method is applied to solve Fourier-Kirchoff's equation in heat transfer problems for flat plate solar collectors. Probabilistic models have been presented for the steady and non-steady conditions. The mathematical description of these models has been derived on the basis of the analogy between the conduction difference equation and the equation describing walking particle movement. The results of computations performed by the Exodus method have been compared to the results obtained by the Equivalent Thermal Network and the Finite Difference methods. The Exodus procedure allows the influence of changeable weather and operating conditions to be considered in calculations.
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Authors and Affiliations

Alicja Siuta-Olcha
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Abstract

The paper presents an evaluation of MV/LV power transformer damage risk due to the impact of ambient temperature at their operation location. It features a presentation of the method of evaluating the power structures’ reliability in the conditions of the structures’ variable durability and exposure values. Based on perennial observations of ambient temperature and failure rate of MV/LV transformers, it was demonstrated that temperature is a factor that causes damage or is jointly responsible for the damage caused in all of the devices’ other failures.
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Authors and Affiliations

Andrzej Łukasz Chojnacki
1
ORCID: ORCID

  1. Department of Power Engineering, Power Electronics and Electrical Machines, Kielce University of Technology, Poland
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Abstract

High-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) are a candidate for electrical energy supply devices in more and more applications. Most notably in the aeronautic industry. Before any use, an HT-PEMFC is preheated and after that supplied with its active gases. Only at this state, the diagnostics can be performed. A method of testing not requiring a complete start-up would be beneficial for many reasons. This article describes an extended version of the charging and discharging diagnostic method of HT-PEMFCs with no active gases. This extended approach is named “Test Without Active Gases” (TWAG). This paper presents original research on the influence of nitrogen temperature and pressure on the HT-PEMFC response to charging and discharging. A lumped-element model of an HT-PEMFC is also presented. A numerical result of using this model to recreate an experimentally obtained curve is also presented.
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Authors and Affiliations

Wojciech Rosiński
1
ORCID: ORCID
Christophe Turpin
2
ORCID: ORCID
Andrzej Wilk
1
ORCID: ORCID

  1. Faculty of Electrical and Control Engineering, Gdansk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdansk, Poland
  2. Team GENESYS, Laboratioire LAPLACE, 118 Rte de Narbonne, 31077 Toulouse, France
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Abstract

Aiming at the problems of delay and couple in the sintering temperature control system of lithium batteries, a fuzzy neural network controller that can solve complex nonlinear temperature control is designed in this paper. The influence of heating voltage, air inlet speed and air inlet volume on the control of temperature of lithium battery sintering is analyzed, and a fuzzy control system by using MATLAB toolbox is established. And on this basis, a fuzzy neural network controller is designed, and then a PID control system and a fuzzy neural network control system are established through SIMULINK. The simulation shows that the response time of the fuzzy neural network control system compared with the PID control system is shortened by 24s, the system stability adjustment time is shortened by 160s, and the maximum overshoot is reduced by 6.1%. The research results show that the fuzzy neural network control system can not only realize the adjustment of lithium battery sintering temperature control faster, but also has strong adaptability, fault tolerance and anti-interference ability.
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Authors and Affiliations

Zou Chaoxin
1
Li Rong
1
Xie Zhiping
1
Su Ming
1
Zeng Jingshi
2
Ji Xu
1
Ye Xiaoli
1
Wang Ye
1

  1. Guizhou Normal University, China
  2. Guizhou Zhenhua New Material Co., Ltd., China
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Abstract

The aim of this study was to evaluate biomarkers of heat stress (HS) from an automatic milk- ing system (AMS), the relationships between measurements of the temperature-humidity index (THI), reticulorumen pH and temperature, and some automatic milking systems parameters in dairy cows (rumination time (RT), milk traits, body weight (BW) and consumption of concen- trate (CC)) during the summer period. Lithuanian Black and White dairy cows (n=365) were selected. The cows were milked with Lely Astronaut® A3 milking robots with free traffic. Biomarkers were collected from the Lely T4C management program for analysis. The pH and temperature of the contents of the cow reticulorumen were measured using specific Smax-tec boluses. The farm zone’s daily humidity and air temperature were obtained from the adjacent weather station (2 km away). According to this study, during HS, the higher THI positively cor- relates with milk lactose (ML), which increases the risk of mastitis and decreases CC, RT, BW, MY, reticulorumen pH, and F/P. Some biomarkers of HS can be milk yield, milk lactose, somatic cell count, concentrate intake, rumination time, body weight, reticulorumen pH, and milk fat – protein ratio. We can recommend monitoring these parameters in the herd management program to identify the possibility of heat stress.
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Authors and Affiliations

R. Antanaitis
1
M. Urbutis
1
V. Juozaitienė
2
D. Malašauskienė
1
M. Televičius
1

  1. Large Animal Clinic, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės 18, Kaunas, Lithuania
  2. Department of Biology, Faculty of Natural Sciences, Vytautas Magnus University, K. Donelaičio 58, Kaunas, Lithuania
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Abstract

In this paper the current status of microplasma devices and systems made in the LTCC technology is presented. The microplasma characteristics and applications are described.We discuss the properties of the LTCC materials, that are necessary for reliable operation of the sources. This material is well known for its good reliability and durability in harsh conditions. Still, only a few examples of such microplasma sources are described. Some of them have been developed by the authors and successfully used for chemical analysis and synthesis.

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Authors and Affiliations

Jan Macioszczyk
Leszek Golonka

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