Research of vibrations effect on hydraulic valves in military vehicles

The paper discusses minimizing the effect of external mechanical vibration on hydraulic valves in different military hydraulic drive systems.The current research work presents an analysis of the potential to reduce vibration on the valve casing by installing a valve flexibly on a vibrating surface,i.e.,by introducing a material with known stiffness and damping characteristics between the valve casing and the vibrating surface-a steel spring package or special cushions made of elastomer material or of oilresistant rubber.The article also demonstrates that elastomer cushions placed inside the valve casingbetween the casing and the centering springs-can be used as a supplementary or alternative solution in the analyzed method for mitigating the transfer of vibrations.By using materials with appropriately selected elastic and dissipative properties,the effectiveness of vibro-isolation can be increased.The presented theoretical analyzes by linear and non-linear mathematical models have been verified experimentally.

Serum and urine metabolomic fingerprinting in diagnostics of inflammatory bowel diseases

AIM: To evaluate the utility of serum and urine metabolomic analysis in diagnosing and monitoring of inflammatory bowel diseases (IBD).

Characterization of multiphase gas–solid flow and accuracy of turbulence models for lower stage cyclones used in suspension preheaters

This study involved the analysis and characterization of the multiphase flow phenomenon inside the lower stage cyclone separator used in the clinker burning process.The analysis was performed using both CFD and experimental research methods.Very few studies are devoted to such types of cyclone separators,which in addition to their basic functions are also responsible for the technological process.Due to the atypical working conditions of these cyclone separators,they are characterized with a complex geometry,which significantly differs from that of the traditional separators.Furthermore,the evaluation of the accuracy and level of reliability of the two models of turbulence closure—k-e RNG and RSM(RANS),and the LES.The results obtained led to the conclusion that for the lower stage cyclone separators,the LES model proved to be the most accurate(both in the case of forecasting the separation efficiency and pressure drop).The performance parameter(in particular the separation efficiency)values obtained for the RSM model were also characterized by high accuracy.The k-e RNG model was characterized by significantly larger deviations.

Noise Reduction in Industry Based on Virtual Instrumentation

This paper discusses the reduction of background noise in an industrial environment to extend human-machine-interaction.In the Industry 4.0 era,the mass development of voice control(speech recognition)in various industrial applications is possible,especially as related to augmented reality(such as hands-free control via voice commands).As Industry 4.0 relies heavily on radiofrequency technologies,some brief insight into this problem is provided,including the Internet of things(IoT)and 5G deployment.This study was carried out in cooperation with the industrial partner Brose CZ spol.s.r.o.,where sound recordings were made to produce a dataset.The experimental environment comprised three workplaces with background noise above 100 dB,consisting of a laser/magnetic welder and a press.A virtual device was developed from a given dataset in order to test selected commands from a commercial speech recognizer from Microsoft.We tested a hybrid algorithm for noise reduction and its impact on voice command recognition efficiency.Using virtual devices,the study was carried out on large speakers with 20 participants(10 men and 10 women).The experiments included a large number of repetitions(100 times for each command under different noise conditions).Statistical results confirmed the efficiency of the tested algorithms.Laser welding environment efficiency was 27%before applied filtering,76%using the least mean square(LMS)algorithm,and 79%using LMS+independent component analysis(ICA).Magnetic welding environment efficiency was 24%before applied filtering,70%with LMS,and 75%with LMS+ICA.Press workplace environment efficiency showed no success before applied filtering,was 52%with LMS,and was 54%with LMS+ICA.

Applications of Glass and Glass Fiber Retrofit Polymer in Modern Footbridges

The architecture of footbridge design takes the form of a number of submissions from leading architects and engineers, each setting out their views on bridge design--present and future. It looks at the functions of a bridge, defining purpose of place and context, the spirit of creativity and the reasoned progression of an idea. It also explores the exploitation of materials technology and construction innovation and the tension between lightness and mass and between sculpture and scale. Present parameters of tempered and laminated glass create possibility of modern architecture of footbridges which are being full of transparency and light reflex effects. Four projects, using glass panels designed by Santiago Calatrava, have been presented in this paper. GFRP （glass fiber retrofit polymer） makes new horizon in material technology, helps to enrich new conception of structure with longer durability, low weight of deck and new creation of architecture line. The paper has described a few results of FEM （finite element method） analysis of footbridge with modular bridge GFRP deck system. The footbridge was excited by impact and human-induced vibrations. Composite material consists of glass fibers and polymer matrix is a promising alternative against traditional materials. New architecture and modern material engineering are looking for fresh possibilities of form and shape of structure, long durability and extraordinary technical parameters of building elements.

Kinetic Study of the Aldol Condensation of Isobutyraldehyde Catalyzed by Sodium Hydroxide

The initial step of works on the designing of a mathematical model of a commercial process to manufacture a mixture of butyric acid hydroxyesters, for use in ecological solvent compositions for the paint and varnish industry, is presented in the paper. The works referred to in this paper relate the mathematical model of the condensation reactor. A unit process kinetic model was designed based on an analysis of the general differential form of the equation of the reactor mass balance and an analysis of the mechanism of the Tishchenko aldol condensation reaction, as used in the synthesis of butyric acid hydroxyesters, confirmed by the results of GC/MS analysis. The forms of the kinetic equations obtained were verified experimentally by determining the values of the respective reaction rate constants.

Assessment of internal defects of hardfacing coatings in regeneration of machine parts

This paper presents the use of computed tomography for the evaluation of hardfacing. The method used in this research is hardfacing by tungsten inert gas using alloy wires of wear resistant layers. This paper discusses the latest materials used for hardfacing and their application. It characterizes the defects of obtained hardfacing and impact of the type of wire on the concentration of defects. It further, the basic mechanical properties of coatings were determined. The results are subjected to qualitative and quantitative analysis. The smallest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-600 HB, which amounts to 1.5%. The highest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-500 HB, which amounts to 7.2%. The chemical composition of hardfacing has been presented.

Simulation of Rock Complex Resistivity Using an Inversion Method

The complex resistivity of coal and related rocks contains abundant physical property information,which can be indirectly used to study the lithology and microstructure of these materials.These aspects are closely related to the fluids inside the considered coal rocks,such as gas,water and coalbed methane.In the present analysis,considering different lithological structures,and using the Cole-Cole model,a forward simulation method is used to study different physical parameters such as the zero-frequency resistivity,the polarizability,the relaxation time,and the frequency correlation coefficient.Moreover,using a least square technique,a complex resistivity“inversion”algorithm is written.The comparison of the initial model parameters and those obtained after inversion is used to verify the stability and accuracy of such approach.The method is finally applied to primary-structure coal considered as the experimental sample for complex resistivity measurements.

Possibility of Using Ni-Co Alloy As Catalyst for Oxygen Electrode of Fuel Cell

In recent years, the scale of use of fuel cells （FCs） has been increasing continuously. One of the essential elements that affect their work is a catalyst. Precious metals （mainly platinum） are known for their high efficiency as FC catalysts. However, their high cost holds back the FCs from application on a large scale. Therefore, catalysts that do not contain precious metals are sought. Studies are focused mainly on the search for fuel electrode catalysts, but for the efficiency of FCs also the oxygen electrode catalyst is of great significance. The paper presents an analysis of the possibilitiesof using Ni-Co alloy as a catalyst for the oxygen electrode of the FC.

The Brand ＂Made in China＂ as a Part of the Growth of the China＇s Competitive Advantage

In the eyes of consumers, each product has some kind of origin （its country, region, and continent）. The image of the place of origin influences the assessment of products and brands （brand image） they come from. Traditionally, consumers extrapolate the characteristics of the country and its inhabitants on the characteristics of the product. Chinese products are very common and they can be purchased almost anywhere. The consumer does not have to take any special efforts to acquire products ＂made in China＂. Many of these products do not have specific characteristics that allow them to be considered as the unique. Products, whose names indicate the place of origin, are witnessing an increasing popularity. In the case of products ＂made in China＂, the matter is different. Often, consumers do not admit that they purchase goods produced in China. Research on consumer behaviour in the market of chines products, conducted among Polish citizens, indicated that these products are readily bought. This article presents the results of the research on consumers＇ attitudes towards regional ＂made in China＂ which was conducted in April 2015 among Polish citizens. Furthermore, the article will include the comparison of attitudes towards Chinese products between consumers from Poland and other European countries.

Semantic Differential as an Assessment Tool of （Dis） Advantages of QMS in the Light of Accredited Certification in Poland

This article is a continuation of the issue in the field of assessment of （dis）advantages resulting from the implementation of the quality management systems （QMS） in a structure of the organization. The publication uses the results of studies conducted in the range of assessment＇s information completeness provided by the certification bodies （CBs） in the context of advantages and disadvantages of the QMS implementation in accordance with PN-EN ISO 9001. In addition, an attempt to define a tool for the QMS assessment of （dis）advantages in the organization has been made. The basis for empirical analysis of the issue was the information provided by an accredited management systems CBs recommended by the Polish Centre for Accreditation （PCA）. There are 33 units in Poland, which were granted by PCA with the accreditation within the range of ISO 9001：2008. In the first stage of the research work, a substantive analysis of websites content among mentioned CBs has been carried out. In addition, the paper proposes use of semantic differential method （SD） to evaluate （dis）advantages of the QMS. SD adaptation for the assessment of the QMS （dis）advantages is the authorial concept. The authors hope for polemic in this area. In the face of obtained results, an authorial SD construction has been proposed, which is useful and may help in the formulation and conveying of the relevant （reliable） information to potential clients in the range of （dis）advantages resulting from the QMS implementation to the organization. As a consequence, the recommendations have been set, which are kind of guidelines that could significantly influence the realignment of the information state conveyed on the internet by the CBs.

Effect of the Microclimate of Underground Systems on the Occurrence of Hibernating Bats

This study investigates the microclimatic connections between underground systems and the hibernation sites of particular species of bats. The distribution of hibernating bats was analysed in five selected zones designated Ⅰ-Ⅴ. These zones have a similar relative humidity, diverse temperature ranges inside the system, as well as air flow rates. A multi-year research programme highlighted the relationships between the occurrence of hibernating bats of various species and the microclimate of these particular zones. What is of essential importance are the sites with an air flow in their zones exceeding 0.02 m·s^-1, then is temperature and humidity. The air flow determines more intensive settling of wintering bats （zones Ⅲ, Ⅳand Ⅴ）. The zone Ⅱ-tourist zone with periodic air flows and often visited by humans is the least used by hibernating bats.

Soil Microbial Activity and Functional Diversity in Primeval Beech Forests

Virgin forests are unique ecosystems, which can be used as etalon for basic biocoenotic investigation. Soil microorganisms are very sensitive reagents on influence of biotical factors, and at the same time are the active producers of phytotoxic and phytostimulating exometabolites. Studies of soil microbiota were conducted in virgin beech forests of Shyrokoluzhansky massif of the Carpathian Biosphere Reserve. It was found the ratio and the number of different ecological-trophic groups of soil microorganisms changes with altitude. So the number of ammonificators with increasing of altitude above sea level was reduced. The soil at altitude of 1,100 meters above sea level was characterized by minimum content of organotrophes -1.22 × 10^6 （CFU-colony forming units/lg.a.d.s.）. At the altitude of 500 meters content of ammonificators increased at six times and was 7.07 ×10^6 CFU/lg.a.d.s., which indicates to accumulation of the soil organic matter. Similar changes occurred with the number of bacteria which are using mineral forms of nitrogen for their nutrition. Their maximum quantity （4.32 × 10^6 CFU/lg.a.d.s.） was in the soil of biotope disposed at altitude of 500 meters above sea level. Fluctuations in the number of soil micromycetes of virgin forest ecosystems have not been as significant as the bacterial microbiota （within 17 ×10^3-28 × 10^3 CFU/lg.a.d.s.）. Among a wide spectrum of bacterial microbiota were isolated strains with high phytostimulating action.

Post-traumatic stress disorder among homeless adults in Poland: Prevalence and predictors

BACKGROUND: Symptoms of Post-Traumatic Stress Disorder (PTSD) have often been found in studies on homeless people, due to high rates of traumatic experiences. Most research on homelessness has been conducted in North America and Western Europe. However there are many social and cultural factors which can impact the prevalence and number of PTSD symptoms. AIMS: This study sought to determine the prevalence and predictors of trauma and PTSD symptoms among homeless adults in an Eastern European nation (Poland). METHOD: Randomly chosen residents of shelters were interviewed (N = 200). The respondents were asked about symptoms of PTSD, alcohol abuse/dependence, depression symptoms and perceived social support. RESULTS: The data indicated that 30% of the homeless sample were victims of traumatic events, 22% showed at least one PTSD symptom, and 7% met criteria for a lifetime diagnosis of PTSD. Symptoms of PTSD were the most common among those who had symptoms of alcohol abuse/ dependence and depression. CONCLUSION: The study’s findings support the need to attend to mental disorders such as PTSD when addressing the array of needs of homeless people.

Bridge Structures with GFRP Composite Deck

In this paper, author’s first part of research of GFRP bridge deck (using ASSET fiber line composite modular system) took part at AGH University of Science and Technology Laboratory of Glass Technology and Amorphous Coatings Department. The analysis consisted spectrometer analysis of chemical constitution of glass fiber, identification of material according to Fourier spectroscopy, electronic scan microscopy (SEM/EDAX) and DTA analysis. The modal FEM analysis of chosen footbridge with light GFRP deck has been presented in the paper.

CVT动力系统中的换档速度控制

与无级变速器密切相关的是要解决选择车辆中传动系速比的问题。对于值得重视的传动系速比范围的情况,与曲轴有关的回转件的质量影响到传递至从动轮的功率。本文的理论研究和结果分析清晰表明,在CVT控制算式中必须考虑换档速度。

Amateur Sports of the Elderly: A Chance for Health and a Higher Quality of Life

A significant increase in sports-leisure activity events in recent years presents the opportunity to compete in all age categories. Among the many sport varieties, special attention ought to be paid to amateur sports—recreational sports, particularly in the context of the increasing leisure time among the elderly. Recreational sports activities are free of many distortions and defects of the modern professional sport. Recreational sports are egalitarian, not exclusive. The health paradigm is always at the heart of it, along with a strong emphasis on hedonism. Sport activities reveal self-fulfillment as the highest needs, giving fulfillment and satisfaction. The ease in the selection of a sports goal makes the amateur sports an important tool for the shaping of persons’ life and health. A sports goal, which is participating in sports events, provides a strong motivation for systematic work. Striving for transgression is a source of strong emotions and satisfaction. Struggling with a persons’ own body, with old age, may be a valuable challenge that would positively impact wellbeing in the psychosocial aspect. This study shows a social phenomenon of sports activity among the elderly, dynamically growing in Poland. It also presents multiple benefits for the general wellbeing as well as the potential threats which a lack of distance to the sports rivalry may cause when it crosses the line behind which a persistent pursuit of the purpose (sport result) may end up in health damage. The line between recreation and sport is thin and difficult to distinguish. Animators, trainers, and instructors need to skillfully manage the interests of older people so that their involvement in physical activity determines a safe and healthy lifestyle.

Investigation of Propoxylation and Ethoxylation of 2-Ethylhexanol in the Presence of an Alkaline and DMC Type Catalyst at Initial Stages of the Syntheses

This paper reports the results of monopropoxylation and monoethoxylation of ethylhexyl alcohol performed in the presence of KOH and a DMC type catalyst, respectively. The existing differences are discussed in terms of kinetic performance of the syntheses, as well as the obtained products＇ compositions. The investigated DMC type catalyst showed 60 to 70 times as high conversion rates, narrower homolog distributions and higher selectivity, in comparison with KOH. Interpretation of the experimental results was performed using kinetic parameters of the WeibulI-Nycander-Gold model and the Natta Mantica relationships. In spite of any differences between the reactivity of the investigated catalysts and alkylene oxides, a significant contribution ofpolymerisation parallel to the target polyaddition was determined, absorbing a major part of the converted adducts, both in the presence of DMC and KOH.

Difficulties in post-stroke gait improvement caused by post-stroke depression

Background Depression is a common problem impeding post-stroke rehabilitation.Up to 70% of patients show depression symptoms during the first twelve months after stroke onset.However,the depression and its effect on functional recovery can be difficult to diagnose.The purpose of this study was to use gait analysis as a tool to compare the recovery after stroke in patients with and without depression and to assess the impact of the initiation time of rehabilitation after stroke onset.Methods One hundred and forty five consecutive patients after first ever stroke admitted for designed rehabilitation program within 2 to 31 months after stroke onset participated.All patients received 4 weeks treatment program included comprehensive rehabilitation consisted of multipurpose activities 5 days a week.These included individual and group exercises,physiotherapy,occupational therapy and gait training.Gait analysis with Kistler force plates was employed to assess gait pattern symmetry before and after the treatment.Gait symmetry was evaluated based on seven gait parameters.Regaining of gait pattern symmetry was assumed as a measure of rehabilitation outcome.Results After rehabilitation program gait symmetry w（）ined in patients without depression.Gait asymmetry remained unchanged in patients diagnosed with depression.No major differences in outcome from rehabilitation were noted in regards to the initiation time of rehabilitation after the stroke onset.Conclusions Depression limits gait recovery after stroke.The time of initiation of rehabilitation after stroke onset does not limit the motor recovery after rehabilitation program.