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Abstrakt

The activity of territorial self-government shaped institutionally during the development process is characterized by a significant scope of care for the financial situation, which determines the efficiency of its functioning. The general availability of public services is a condition for the assessment of the activities of municipalities (powiats, voivodeships). Institutional economy as a real one, takes into account an integrated point of view. The aim of the study is to present the territorial differentiation of the eff ectiveness of communes’ activities in the context of institutional economics and to present the possibility of using a synthetic measure in this process. The synthetic measure of development fluctuated within the limits of 0.30 – Wąchock (Starachowice poviat, urban-rural commune) to 0.41 – Ostrowiec Św. (Ostrowiecki poviat, urban commune) in 2009, 0.32 – Łączna (Skarżysko poviat, rural commune) to 0.40 – Starachowice (Starachowice poviat, municipal commune) in 2015. The results of the analysis confirm the existence of small differences in the assessment of development communes of the Kamienna Basin. This approach allows the assessment of municipalities using one size and allows you to organize the analyzed objects in terms of the considered phenomenon.
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Abstrakt

The paper presents a method of measuring the angle of rotation and twist using a tilted fibre Bragg grating (TFBG) periodic structure with a tilt angle of 6◦, written into a single-mode optical fibre. It has been shown that the rotation of the sensor by 180◦ causes a change in the transmission coefficient from 0.5 to 0.84 at a wavelength of 1541.2 nm. As a result of measurements it was determined that the highest sensitivity can be obtained for angles from 30◦ to 70◦ in relation to the basic orientation. The change in the transmission spectrum occurs for cladding modes that change their intensity with the change in the polarization of light propagating through the grating. The same structure can also be used to measure the twist angle. The possibility of obtaining a TFBG twist by 200◦ over a length of 10 mm has been proved. This makes it possible to monitor both the angle of rotation and the twist of an optical fibre with the fabricated TFBG.
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Abstrakt

Skuteczna ochrona (wzmocnienie obudowy) skrzyżowania ściana–chodnik zapewnia ciągłość cyklu produkcyjnego, a mianowicie szybkie przesunięcie przenośnika ścianowego do czoła ściany. Stosowanie niskiego bądź wysokiego kotwienia jako elementu wzmacniającego obudowę podporową skrzyżowania ściana-chodnik, pozwala na wyeliminowanie tradycyjnych sposobów utrzymania skrzyżowania ściana–chodnik, a tym samym pozwala na efektywne wykorzystanie wysokiej wydajności nowoczesnych kompleksów ścianowych. W artykule przedstawiono długoletnie doświadczenia dołowe kopalni Knurów–Szczygłowice w zakresie stosowania, dla skutecznego utrzymania skrzyżowania ściana-chodnik, obudowy przykotwionej do górotworu przy pomocy dwóch par kotwi, wykazując pełną przydatność techniczną i ekonomiczną takiego sposobu wzmocnienia obudowy. W artykule zwrócono również uwagę na bezpieczeństwo pracy oraz na coraz powszechniejsze wykorzystanie badań endoskopowych przy określeniu zasięgu strefy spękań rzutujące bezpośrednio na właściwy dobór odpowiedniej liczby, nośności oraz długości stosowanych kotew. Przeprowadzone badania dołowe zasięgu strefy spękań i rozwarstwień stropu (endoskopowe i przy pomocy rozwarstwieniomierzy linkowych) przed frontem czynnej ściany, a także przeprowadzone badania laboratoryjne (stanowiskowe) pozwoliły określić współczynnik bezpieczeństwa utrzymania skrzyżowania ściana–chodnik rzutujący bezpośrednio na konieczność zabudowy dodatkowego wzmocnienia. Wartość współczynnika bezpieczeństwa Sbść-ch większa od 1 jest korzystna i bezpieczna, a wartość mniejsza lub równa 1 może prowadzić do znacznego pogorszenia warunków utrzymania skrzyżowania w obudowie podporowej przykotwionej.
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Abstrakt

Four and a half years of African Swine Fever (ASF) in population of free-ranging wild boars and domestic pigs revealed a number of novel insights into the disease epidemiology. Until November 20th, 2018, in total 3048 cases in wild boars and 213 outbreaks in domestic pigs have been confirmed. In spite of low contagiosity as well as low rate of ASF spread in wild boars the disease has an enormous socio-economical impact on the production of pigs in Poland. One of the most important aspects which directly influences the dynamics of ASF spread is the unpredictable hu- man activity. Another important factor responsible for continuous ASF spread is fast recovery of wild boar population in spite of efforts taken by hunters. Assuming our scientific opinion ASF seems to be present in wildlife for the incoming few or several years. Therefore, extraordinary measures should be prepared and undertaken to limit the risk of the occurrence of future out- breaks in domestic pigs. One of the most crucial issues is implementation of strict biosecurity measures in all domestic pigs holdings.
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Investigations of operating parameters of widely used sand mixers reveal a wide variability range in the values of parameters associated with their power demand. Power efficiency of manufacturing processes has received a great deal of attention lately, which encourages the research efforts to optimise this aspects of operation of machines and installations as well. In the first place these machines and installations have to work properly as a part of the process line- which applies also to moulding sand mixers. Experiments conducted by the authors suggest that the same goal can be achieved at variable energy input levels. To obtain information about the power demands of sand mixers requires the use of highly specialised equipment, methodology and result processing procedures. This study provides a brief characteristic of measurement equipment and results of measurements taken on a unit AG-015 (based on a roller mixer) and a laboratory rotor mixer.
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Abstrakt

Niniejszy artykuł na tyle, na ile dostępna jest literatura, empiryczne pomiary oraz dane z modeli mezoskalowych opisuje i porównuje spodziewane warunki wietrzności na terenie Morza Bałtyckiego. Nawiązuje do problematyki związanej z projektowaniem oraz oceną spodziewanej produktywności farm wiatrowych na analizowanym terenie, w odniesieniu do dotychczasowych doświadczeń autora związanych z energetyką wiatrową na lądzie. W kolejnych rozdziałach niniejszej publikacji opisano stan obecny oraz prespektywy rozwoju energetyki wiatrowej w obrębie Morza Bałtyckiego. W dalszej części dokonano oceny potencjału tego akwenu, przy użyciu modeli mezoskalowych oraz danych empirycznych z masztu Fino 2, zlokalizowanego w odległości ok. 200 km od większości terenów wskazanych w projekcie miejscowych planów zagospodarowania przestrzennego obszarów morskich Polski jako przeznaczonych pod rozwój enegetyki morskiej (Draft plan... 2018). W rozdziele dot. modeli mezoskalowych szczególną uwagę poświęcono modelowi GEOS5.12.4 jako źródle danych The Modern-Era Retrospective Analysis for Research and Application zwanych w skrócie MERRA2 (Administration National Aeronautics and Space Agency 2018), które od lutego 2016 r. zastąpiły dane MERRA (Thogersen i in. 2016) oraz zyskały wysokie zastosowanie w ocenach produktywności przedinwestycyjnych, jak i realizowanych w fazach operacyjnych projektów farm wiatrowych ze względu na dobry poziom korelacji z danymi in situ. Dane z tego modelu uzyskano dla ośmiu lokalizacji, pokrywających się w dużej mierze z lokalizacjami obecnie istniejących morskich farm wiatrowych w obrębie Morza Bałtyckiego. Znaczącą cześć niniejszej publikacji poświęcono opisowi wczesniej wspomnianego masztu Fino 2 oraz analizie danych, rejestrowanych przez czujniki umieszczone na tym maszcie (Federal Maritime and Hydrographic Agency 2018). Analiza została przeprowadzona z użyciem skryptów opracowanych w języku programowania VBA umożliwiającym łatwiejszą pracę z dużymi ilościami danych. Pomiary z masztu Fino 2 wraz z użyciem pomiarów długoterminowych pochodzących z modeli mezoskalowych mogą zdaniem autora posłużyć w pewnym stopniu, do wstępnej oceny przewidywanej produkcji farm planowanych do zlokalizowania w obrębie terenów przeznaczonych pod rozwój energetyki odnawialnej w planie zagospodarowania przestrzennego morskich wód wewnętrznych, morza terytorialnego i wyłącznej strefy ekonomicznej Polski (Draft plan... 2018). W części końcowej artykułu podsumowano informacje dot. przewidywanych warunków wietrznych Morza Bałtyckiego w szczególności na terenie wyłącznej strefy ekonomicznej Polski. Zwrócono uwagę na różnice pomiedzy energetyką wiatrową morską a lądową oraz zaproponowano dalsze, konieczne zdaniem autora kwestie, które powinny zostać zbadane w celu optymalnego pod kątem technicznym rozwoju energetyki wiatrowej offshore.
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Abstrakt

The paper attempts to analyze distortions of cast iron and cast steel rings, after heat treatment cycles. The factors influencing distortion are: chemical composition of material, sample geometry, manufacturing process, hardenability, temperature and heat treatment method. Standard distortion tests are performed on C-ring samples. We selected a ring-model, which approximate the actual part, so that findings apply to gear rings. Because distortion depends on so many variables, this study followed strictly defined procedures. The research was started by specifying the appropriate geometry of the samples. Then, the heat treatment was conducted and samples were measured again. The obtained results allow to determine the value of the resulting distortion and their admissibility. The research will be used to evaluate the possibility of using the material to produce parts of equipment operated under extreme load conditions.
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Abstrakt

In the paper, presented is a research on effectiveness of absorbing electromagnetic waves at frequency 2.45 GHz by unhardened moulding sands prepared of three kinds of high-silica base and a selected grade of sodium silicate. Measurements of power loss of microwave radiation (Pin) expressed by a total of absorbed power (Pabs), output power (Pout) and reflected power (Pref) were carried-out on a stand of semiautomatic microwave slot line. Values of microwave power loss in the rectangular waveguide filled with unhardened moulding sands served for determining effectiveness of microwave heating. Balance of microwave power loss is of technological and economical importance for manufacture of high-quality casting moulds and cores of various shapes and sizes. It was found that relative density influences parameters of power output and power reflected from samples of moulding sand placed in a waveguide. Absorption expressed by the parameter Pabs is not related to granularity of high-silica base: fine, medium and coarse. It was found that the semiautomatic microwave slot line supports evaluation of effectiveness of microwave absorption on the grounds of power loss measurements and enables statistic description of influence of relative density of the sandmix on penetration of electromagnetic waves in unhardened moulding sands.
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Abstrakt

Beamforming is an advanced signal processing technique used in sensor arrays for directional signal transmission or reception. The paper deals with a system based on an ultrasound transmitter and an array of receivers, to determine the distance to an obstacle by measuring the time of flight and – using the phase beamforming technique to process the output signals of receivers for finding the direction from which the reflected signal is received – locates the obstacle. The embedded beam-former interacts with a PID-based line follower robot to improve performance of the line follower navigation algorithm by detecting and avoiding obstacles. The PID (proportional-integral-derivative) algorithm is also typically used to control industrial processes. It calculates the difference between a measured value and a desired set of points, then attempts to minimize the error by adjusting the output. The overall navigation system combines a PID-based trajectory follower with a spatial-temporal filter (beamformer) that uses the output of an array of sensors to extract signals received from an obstacle in a particular direction in order to guide an autonomous vehicle or a robot along a safe path.
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Abstrakt

An analysis of the influence of inverter PWM speed control methods on the operation of a brushless DC (BLDC) motor was carried out. Field-circuit models of the BLDC motor were developed taking into account rotational speed control by two classic methods: the unipolar H_ON_L_PWM and the bipolar H_PWM_L_PWM. Waveforms of the electrical and mechanical quantities and the motor parameters were computed. The results of the computations were verified by measurements performed on a specially designed test stand. On the basis of the measuredwaveforms of the electrical and mechanical quantities the dependence of the drive system efficiencies and power losses on rotational speed was determined for the two methods of inverter control.
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Abstrakt

Most of sound sources are complex vibroacoustic objects consist of numerous elements. Some coupled vibrating plates of different shapes and sizes can be easily found in urban environments. The main aim of this study is to determine the sound radiation of coupled plates system of practical importance. The investigated vibroacoustic system consist of a thin circular plate coupled with a thick flat baffle with a circular hole. The circular plate has been mounted to the baffle’s hole using screws and two steel rings. The measurement setup was located inside a semi-anechoic chamber to assure the free field conditions. It was necessary to take into account the whole system surface to obtain the radiation efficiency based on the Hashimoto’s method. Such an approach can be troublesome and time-consuming. Therefore, the criterion has been proposed which allows the vibration velocity measurements and calculations to be performed only for the thin plate’s area. An alternative approach has been proposed based on the classical Rayleigh integral formula. Its advantage is a simpler implementation in a computer code. The obtained results have been compared with the theoretical results obtained for the elastically supported circular plate. A good agreement has been obtained at low frequencies.
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Abstrakt

Vacuum conditions in foundry installations are generated using electric-driven vacuum pumps. The purpose of the experiment is to evaluate the performance of a vacuum-assisted system for compaction of moulding sand basing on registered plots of selected electric power parameters of the power-supplying system of the pumps. Model testing done on an experimental vacuum system installation, power-supplied from a system incorporating the recorders of instantaneous current and voltage values. Following the numerical procedure, the experimental data are analysed to yield mathematical relationships between the variations of the generated vacuum pressure levels and variations of selected electric power parameters. Registered and computed values of selected parameters: instantaneous and RMS voltage and current values, active, reactive and apparent power levels and power coefficient allow for diagnosing the adequacy and reliability of the system operation. According to the authors, the applied monitoring of the power parameters of a vacuum-assisted installation may become an effective and easy practical method of evaluating the performance of such installations, used also in foundry plants.
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Abstrakt

In this article the main problems related with the proper choice of the design and operation parameters of vacuum installation in vacuum moulding system have been discussed. In such system a vacuum are generated using electric-driven vacuum pumps. The aim of the experiment is to evaluate the performance of a vacuum system basing on registered plots of selected electric power parameters of the power-supplying system of the pumps with parallel measurements instantaneous values of pressure in selected points of model stand. The measurements system for power-supply unit has incorporated the recorders of instantaneous current and voltage values. Following the suitable numerical procedure, the experimental data are analysed to yield mathematical relationships between the variations of the generated vacuum pressure levels and variations of selected electric power parameters. According to the authors, the applied measurements system of the parameters of a vacuum-assisted installation may become an effective and easy practical method of evaluating the performance of such installations, used also in industry.
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Abstrakt

This paper presents a novel sideslip angle estimator based on the pseudo-multi-sensor fusion method. The kinematics-based and dynamics-based sideslip angle estimators are designed for sideslip angle estimation. Also, considering the influence of ill-conditioned matrix and model uncertainty, a novel sideslip angle estimator is proposed based on the wheel speed coupling relationship using a modified recursive least squares algorithm. In order to integrate the advantages of above three sideslip angle estimators, drawing lessons from the multisensory information fusion technology, a novel thinking of sideslip angle estimator design is presented through information fusion of pseudo-multi-sensors. Simulations and experiments were carried out, and effectiveness of the proposed estimation method was verified.
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