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1
Content available remote

Theoretical and Experimental Study of a Cement Finish Mill

100%
Magraoui R., Temmar M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
507-510
EN
In this work, we study the dynamic behavior of a cement crusher. During its operation, several faults can occur. Our objective is to monitor the gear defect and other defects and make the necessary corrections. We model a part of the system: the gear transmission of the entire pinion-crown. We proceed to the simulation using a simulation program. Afterwards, we study the vibration behavior of the entire kinematic chain of the machine where we conduct programming vibrations of measurement points across all levels using vibration analysis software. The vibration measurements are realized with the aid of a data collector. The results of theoretical simulation are confronted with the analysis of experimental vibration measurements in order to determine the severity of mechanical faults and to establish an adequate vibratory prognosis.
2
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Applying a Numerical Model to Obtain the Temperature Distribution while Machining

100%
Melzi N., Temmar M., Ouali M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
504-506
EN
The turning process is one of the best used processes in the mechanical industry. Therefore, the choice of the cutting parameters is very important in order to obtain a good machined surface quality. In this study, an analytical model and a modeling of the contact of the cutting tool with the work piece are developed for an orthogonal cutting process with a thermal analysis at the contact. The main aim is to predict the temperature while machining. By using the high-speed machining, we notice that the greater part of the heat, generated by the cutting process, is discharged into the cutting tool and the work piece. Indeed, when the cutting parameters, such as the cutting speed or the feed increase, the temperature increases too.
3
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Searching for New Measurement Solutions in the Area οf Estimating Danger of Local Vibrations at Workplace

63%
Barański R.
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issue 1
3-6
EN
There is a lot of controversy when we consider the most popular method of measuring local vibrations to estimate danger on hand tools operators. This is because of commonly used adapter that represents many faults, from which the most significant are: strong impact of grip and placing adapter between a hand and a tool handle. What we propose in this article is a measurement system including a band placed on a wrist. This solution highly eliminates defects mentioned above, but seems to be too trivial to maintain high quality of measuring process. The purpose of this article is to estimate the quality of this new solution in respect of some basic categories in which measurement errors occur.
4
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The Spectral Response of Hand-Arm System

63%
Barański R., Batko W.
Acta Physica Polonica A
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2011
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vol. 119
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issue 6A
913-915
EN
Recently we have used better solution to protect hand tool operators. In spite of our good intentions there is still endanger on high level vibration. For that reason we need to improve protection constantly. One of the most important properties of hand-arm system is knowledge about spectral response. In this article we try to obtain spectral response in narrow band-pass filters in accordance with IEC 1260:1995 and ANSI S1.11-2004 standards (implemented in LabVIEW software). To measure signals we used accelerometer placed on a wrist and on a tool. Of course the vibrations are attenuated by hand (cartilage, muscular tissue) but the question was what the shape of envelope in measurement range is. Our research used measurement on two different systems. The one was based on vibration inductor (laboratory environment), the second one used drill (real environment). This research is a part of a wider project to make virtual model of hand-arm system.
5
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Design of Wave Energy Converter System with Linear Generator

63%
Şahin M., Özdinç I.
Acta Physica Polonica A
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2015
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vol. 128
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issue 2B
B-243-B-245
EN
It is not wrong to say that wave energy will be one of the most important energy sources to be used in the future, when it is thought that three-quarters of the world is covered by water. The initial investment and maintenance costs are the only expenses, beside not any price have to be paid for the primary energy. The wave energy does not leave any contaminants, as well as it is cheap, clean, environmentally, friendly and a great energy sources. In this study, wave energy converter system which has a four poles linear generator is discussed. The Linear generator model has been designed and created as a portable model. The results obtained from this model were examined.
6
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Hand Grip-EMG Muscle Response

63%
Barański R., Kozupa A.
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vol. 125
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issue 4A
A-7-A-10
EN
One of the most important factors in hand-arm system research is the information about hand grip force and pressing force on a tool handle. This article focuses on an alternative method to measure grip force. For grip force, one of the most popular solutions is a special handle with force sensors. However, when we want to use it with regular hand tool like e.g. a drill, it seems to be uncomfortable because we must interfere in handle construction. A solution proposed in this article is based on technique for evaluating and recording the electrical activity produced by muscles, electromyography (EMG). It has been assumed that EMG signal will be proportional to muscle tension responsible for palm grip. This solution have one significant advantage when comparing to special handle. It can be used with regular tool without interfering in the handle. Measurement presented in this article have been carried out with use of surface electromyography (sEMG). It is not invasive method which enables to measure EMG signal through placing stickers with electrodes directly on a skin.
7
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Investigation of the Effects of Moving Targets on Hit Force in Taekwondo

51%
Kumartaşli M., Üncü İ., Çatikkaş F., Akyüz M., Kılım O.
Acta Physica Polonica A
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2016
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vol. 130
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issue 1
382-384
EN
The system to be developed has been designed in order to determine the training levels of the athletes in the field of taekwondo at national and international level and to follow-up the talent development process using computer support. The progression and continuity of hit power and time-dependent performance improvement of an athlete can be measured with interactive impact measurement system. The system determines a random target. It marks the target by blue light. When the light turns on, the athlete reacts accordingly and swiftly by kicking without knowing the light timing. The athlete only needs to know where the light is. Unlike in other training systems, the piston has been able to go back and forth in response to the strike of the athlete by means of a moving hydraulic system. The athlete can be pushed back by opening the piston when his/her performance drops down. The piston strike model is deactivated when the performance of the athlete is above a given threshold value. There will be four operating phases in the mechanism depending on the impact speed of the piston. Moving target robotic system analyses various hits in Taekwondo with the aim to determine hit force and reaction time. After completion of the warming up at the first stage, the athlete will be able to increase the workout level from low to high levels and will try to keep the mechanism behind as much as possible. Moreover, the athlete will be able to compare his/her results with results of others. Using this system, the efficiency of athletes can be easily determined and deficiencies can be resolved.
8
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Investigation of the Vibroacoustic Climate inside the Buses Solaris Urbino 18 Used in Public Transport Systems - Driver's Cab

51%
Damijan Z., Skrzyniarz S., Kwaśniewski J.
Acta Physica Polonica A
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2011
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vol. 119
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issue 6A
1068-1072
EN
Despite new technological solutions and attempts to improve the working conditions during driving of vehicles, city bus drivers are still exposed to negative impacts of noise and vibrations, causing stress, increased fatigue and leads to numerous diseases. Therefore it seems merited to investigate the acoustic climate and the working conditions during the operation of Solaris Urbino 18 vehicles, widely used in public transport systems. The main purpose of this research program was to show the impacts that the conditions at work might have on bus drivers or to demonstrate that these impacts do not exist. No extensive major research was done to investigate the influence of the conditions at work on functional stability of bus drivers. Investigation of vehicle vibroacoustic climate in working (normal) environment are led rarely. Measurements often are done in idle run or during ride at manoeuvring site only for 2-3 min. In this paper results of acceleration and noise in idle run are presented for 3 min measurement and for 3 h until ride. All measurements are done in working environment on streets of Tychy city with passengers on board. In this paper detailed numerical analysis of vibroacoustic parameters are presented. Physical parameters like noise spectral analysis in 1/3 octave frequency bands and histogram of acoustic pressure level in the driver's cabin are presented in results.
9
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Impact of Vibroacoustic Climate on Driver's Postural Stability for Eyes Closed in Driver's Cabin

51%
Damijan Z., Skrzyniarz S., Kwaśniewski J.
Acta Physica Polonica A
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2011
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vol. 119
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issue 6A
1073-1076
EN
Several levels of the nervous system are responsible for stability of the vertical position in humans. Three basic inputs are involved: atrial, visual and proprioceptive as well as mechanoreceptors present in the skin. Signals from these inputs control the body posture and its orientation with respect to internal and external reference systems. External systems are formed based on the gravitation field and visual stimuli. Internal systems are generated in the central nervous system by polymodal representations, also referred to as body schema. Some of environmental factors of driver's work place could disturb postural stability. Almost all vehicles are according with actual norms and directives. We investigate how normal week of work has impact on postural stability in new city buses. We concentrate on postural stability for closed eyes. In this paper results of investigation were presented.
10
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A System for Determination of Areas Hazardous for Blind People Using Wave-vibration Markers - Final Conclusions and Technical Application

51%
Wiciak J., Borkowski B., Czopek D.
Acta Physica Polonica A
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2013
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vol. 123
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issue 6
1101-1105
EN
The paper constitutes a summary of the work carried out under the research project entitled The development of the method for marking and identification of the spots dangerous and of special importance for vision impaired persons in the big city with use of the wave-vibration markers. This article discusses key researches conducted during the project, including review of influence of environmental sounds on orientation and mobility of blind and partially sighted people, results of vibration perception threshold measurement taken at the wrist of both hands, measurements of paraseismic vibrations and results of researches on annoyance, recognizability and easiness to learn of selected signals.
11
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Investigation of the Vibroacoustic Climate Inside the Buses MAN SG242 Used in Public Transport Systems

51%
Damijan Z.
|
|
issue 1
27-30
EN
A driver of a municipal transport bus is more liable to vibration-acoustic stimuli connected with the movement of the vehicle than a passenger. In literature on the subject noise and vibration exposures are categorised into passive (whereby passengers are exposed) and active (driver's or machine operator's exposure). Despite new technological solutions and attempts to improve the working conditions during the operation of vehicles, city bus drivers are still exposed to negative impacts of noise and vibrations, causing stress, increased fatigue and lead to numerous diseases. It is required, therefore, that the working conditions for drivers should be monitored on a regular basis. In order that they work safely, their working conditions should be as comfortable as possible, in terms of physical and psychical conditions and free from any nuisance. Therefore it seems merited to investigate the acoustic climate (i.e. acoustic phenomena caused by the sources of noise of vibrations in the function of time and space) and the working conditions during the operation of MAN SG242 vehicles, widely used in public transport systems. The following conclusions can be formulated (based on the conducted tests): the highest effective weighted values of vibration acceleration a_w, eq (0.823 m/s^{2}) (exceedance of the legitimate value) were noted in the passengers' compartment in the middles of the vehicle, the lowest- in the driver's cabin (0.411 m/s^{2}). In the driver's cabin, the peak noise level L_C peak = 138.7 dB was exceeded; as the 1/3 octave analyses show, in the driver's cabin dominates low-frequency noise with the frequency from 10 to 25 Hz and the acoustic pressure level of about 90 dB (G). The research has been conducted within the framework of the author's research no 10.10.130.140 and the statuary ones no 11.11.130.119.
12
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Proposal of a Cost-Saving and Risk Prevention Mechatronic System for Water Consumption Systems of Buildings

51%
Karayel D., Ozkan S., Atali G., Ceylan N., Kilic R.
Acta Physica Polonica A
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2017
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vol. 132
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issue 3
604-607
EN
This study aims to develop an integrated control system to prevent the indoor loss of water. In general, these losses occur while using the hot water, because of forgetting to close the water batteries during the water cuts, or due to faults in washing machines, dishwashers and indoor plumbing systems. In this study, a specialized solution is developed for each type of losses. Then, the developed three subsystems were combined and transformed into an integrated system. This study shows that water losses in the housing can be prevented by using advanced technologies. There are similar systems in practice, but this study is different from the others with regard to its holistic approach, addressing all three problems together. The contribution of the system to economic and social life will be great, when water saving and environmental damage are considered.
13
Content available remote

Investigation of the Vibroacoustic Climate Inside the Buses Solaris Urbino 12 Used in Public Transport Systems

51%
Damijan Z., Iwański D., Dahlke G.
Acta Physica Polonica A
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2012
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vol. 121
|
issue 1A
A-32-A-37
EN
Despite new technological solutions and attempts to improve the working conditions during the operation of vehicles, city bus drivers are still exposed to negative impacts of noise and vibrations, causing stress, increased fatigue and lead to numerous diseases. Therefore it seems merited to investigate the acoustic climate (i.e. acoustic phenomena caused by the sources of noise of vibrations in the function of time and space) and the working conditions during the operation of Solaris Urbino 12 vehicles, widely used in public transport systems. The main aim of the research was to show the influence of the 5 day, 8 h working week on selected psycho-physiological parameters on a driver's organism. It was assumed that the main aggravating factor of the driver's organism are vibroacoustics conditions of a work place. The results of this research will be presented in due course. This work presents the research on vibroacoustic climate in one of many city buses used - Solaris Urbino 12. Investigation of the vibroacoustic climate is the branch of environmental biophysics. The measurements, tests and analysis are genuine because they were carried out under real conditions, with passengers, in the long stretches of time and in the entire route of the vehicle. Presented results are very rarely reported in the literature.
14
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The Influence of General Low Frequency Vibration on Posture Stability

51%
Damijan Z., Uhryński A.
Acta Physica Polonica A
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2012
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vol. 121
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issue 1A
A-28-A-31
EN
The work presents the research and analysis concerning general low frequency vibration and its influence on posture stability. The research was conducted in two phases: a group exposed to vibration - August 2006, a control group: November 2006 in Krynica-Zdrój. An exposed group (29 participants/took part in 19 training sessions, each lasting 20 min, of low frequency vibration, standing position) applied to each participant at fixed time of the day. The low frequency vibration amplitude was 4 mm, while the frequency was 3.5 Hz. Before and after the session the posturographic examination of posture stability was conducted. The control group (33 participants) also took part in 19 everyday 20 min sessions with no vibrations and only measurements conducted. The results were analyzed concerning statistics using Statistica. For the sake of the analysis the significance level was p = 0.05, the parametric t-test and the nonparametric Kolmogorov-Smirnov tests were used for two groups of independent variables. Having conducted the research and analysis, one can state that 20 min exposure to low frequency vibration results in significant changes in posture stability and 19 day long vibration training changes significantly the posture stability among the participants. The observed changes were of positive nature. The work introduces research on the possibility of using low-frequency vibration to improve human stability. The results presented concern biophysics in rehabilitation of posture stability and are not often met in specialist literature.
15
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Studies on Infrasound Noise Emitted by Wind Turbines of Large Power

45%
Boczar T., Malec T., Wotzka D.
Acta Physica Polonica A
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2012
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vol. 122
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issue 5
850-853
EN
The subject area of this article applies to study of infrasound signals generated by the work of modern wind turbines. Infrasound noise measurements were conducted in accordance with assumptions of the EN 61400-11 standard. The object of study was a newly commissioned wind farm with a total electrical power equal to 30 MW. The considered power station consisted of 15 new wind turbines, each with a capacity of 2 MW. Scope of the analysis performed included designation of time runs, depicting temporal changes, and designation of frequency spectra of the recorded infrasound signals. Evaluation of the impact of changes in wind speed was made. Moreover, the scope of analysis, performed in this field, concerned assessment of the impact on the obtained results values of meteorological parameters related to the applied measurement system. Values obtained from measurements were related to and compared with the limits specified in standards and regulations existing in this field.
16
Content available remote

Design and Production Considerations on a Button Type Beam Position Monitor for Use of TAC-TARLA Facility

45%
Tural Gundogan M., Kaya C., Yavas O.
Acta Physica Polonica A
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2017
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vol. 132
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issue 4
1333-1339
EN
Turkish Accelerator and Radiation Laboratory in Ankara (TARLA) facility is a superconducting linac-based infrared free-electron laser light source in the frame of Turkish Accelerator Center (TAC). Construction of the facility premises was completed in 2009, with a continued progress of hardware and infrastructure installation until today. In this respect, a button type beam position monitor (BPM) is designed, produced and tested for use of TARLA facility. Antenna simulations and mechanical design studies based on TARLA electron beam parameters are carried out by the software computer simulation technology. In this paper, its design and production highlights are discussed in detail, and the original results are summarized.
17
Content available remote

Measurement System for Parameter Estimation and Diagnostic of Ultrasonic Transducers

32%
Kluk P., Milewski A., Kardyś W., Kogut P., Michalski P.
Acta Physica Polonica A
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2013
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vol. 124
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issue 3
468-470
EN
The paper presents an architecture and design of measurement system and methods for parameter estimation and diagnostic of ultrasonic transducers used in ultrasonic welding and cutting systems manufactured by Tele and Radio Research Institute. The key element of the ultrasonic welding and cutting system is a high power ultrasonic transducer implemented as a sandwich transducer consisting of a stack of piezoelectric ceramic rings mounted between two masses. High quality welding and cutting demand predetermined frequency characteristic of transducer impedance. Also important are: high energy efficiency, high coupling coefficient, low dielectric loss, and the optimal radiation pattern. In order to manufacture high quality and long-life transducers the piezoelectric rings must be selected and the sandwich transducers diagnosed on the basis of their measured parameters. Presented measurement system takes advantage of the virtual instrument technique in the NI LabVIEW environment. It uses Agilent U2761A Function Generator, U2531A Data Acquisition Unit, and the linear amplifier to measure impedance frequency characteristic in the frequency range of 10 kHz to 100 kHz. Moreover, the system can measure the vibration amplitude in the range of 1 μm up to 100 μm, using an optical sensor, and the temperature of the transducer using a pyrometer sensor.
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