scholarly journals INVESTIGATION INTO THE IMPACT OF SUSPENSION PARAMETERS OF FREIGHT WAGONS ON RUNNING SMOOTHNESS / PREKINIŲ VAGONŲ PAKABOS PARAMETRŲ ĮTAKOS VAŽIAVIMO TOLYGUMUI TYRIMAS

2014 ◽  
Vol 6 (5) ◽  
pp. 538-545
Author(s):  
Vytautas Balevičius ◽  
Stasys Steišiūnas ◽  
Gintautas Bureika

The paper analyses the running smoothness of the rolling-stock as the main feature of wagon dynamics. The running smoothness of the freight wagon is evaluated considering the parameters of vibrations and the oscillation process. During the process of wagon running on the track, the forced oscillations of the elements of the body, chassis and suspension are excited. Four-axle freight wagon movement down the track taking into account the given vertical and lateral irregularities has been simulated using software package “Universal Mechanism”. The dependencies of the oscillation amplitudes of the wagon body on track irregularities and vertical and lateral suspension settings have been defined. The dependencies of wagon suspension settings and derailment stability on changes in the wagon mass have been examined in the paper. Finally, basic conclusions have been given. Straipsnyje nagrinėjama viena pagrindinių vagono dinamikos savybių – važiavimo tolygumas. Riedmenų važiavimo tolygumas vertinamas jų masių svyravimo proceso ir kėbulo vibracijų parametrais. Vagonui važiuojant bėgių kelio nelygumais, sužadinami priverstiniai kėbulo, pakabos ir važiuoklės elementų svyravimai. Programiniu paketu „Universal Mechanism“ sumodeliuotas prekinio keturašio vagono važiavimas keliu, kuriame yra bėgių vertikalių ir skersinių nelygumų. Nustatyta vagono kėbulo svyravimų amplitudžių priklausomybė nuo bėgių kelio nelygumų bei vertikaliųjų ir skersinių pakabos parametrų. Straipsnyje nagrinėjama vagono pakabos parametrų ir stabilumo nuriedėjimui nuo bėgių atveju priklausomybė, kintant vagono masei. Pabaigoje pateiktos išvados.

Innotrans ◽  
2020 ◽  
pp. 43-45
Author(s):  
Inna L. Parahnenko ◽  

The wear hardness of the wheel in the gauge when passing curved sections of the track is a primary factor for traffic safety. This parameter is determined by the ratio of the transverse force that increases when the crew passes the curved section to the dynamic vertical load from the rolling stock on the rail. Using mathematical modeling in the software package «Universal mechanism», it is proved that the use of lubrication on the tracks of both track rails reduces the longitudinal forces by up to 60% in curves of small radius and up to 30% at radius up to 1000 m. It is possible to reduce the transverse forces by at least 15% by applying a lubricant to the track of the inner track rails [1, 2]. The use of the classical method (lubrication of the side surface of the outer rail) did not reveal a significant reduction of the forces.


Author(s):  
V. A. Kravchuk ◽  

The article presents the study results of the impact of steel beam prestressing by wall stretching on changes in the circular frequency, frequency, period, and number of oscillations per minute for free oscillation, and for oscillation taking into account the resistance forces. The forced oscillations of the beam under impulse loading are investigated. There has been carried out a comparative analysis of the dynamic parameters of prestressed beams and conventional beams of equal cross-section with the same load-bearing capacity parameters. The analysis results of the influence of resistance forces on the oscillation process in prestressed beams and conventional beams are submitted. There has been established the time of oscillations damping in the compared beams at free oscillation, taking into account the resistance forces.


Author(s):  
Nikolay Grebennikov ◽  
Alexander Kireev ◽  
Nikolay Kozhemyaka ◽  
Gennady Kononov

<span>The given paper presents a hybrid electromagnetic suspension designed for high-speed vacuum transport, where the main levitation force is generated by permanent magnets, while the electromagnet controls the air gap. The computer model is designed by means of MATLAB/Simulink software package, which allows us to simulate the dynamic operational modes of the system. The calculated studies are carried out when the vehicle accelerating to 1000 km/h with account of track irregularities. Permanent magnets incorporated in the system of electromagnetic suspension make it possible to reduce the energy consumption needed for levitation force generation. </span>


2021 ◽  
Vol 100 (4) ◽  
pp. 318-326
Author(s):  
Evgeniy Yu. Bersenev ◽  
Vladimir I. Dubinin ◽  
Vyacheslav M. Ermakov ◽  
Anna I. Kirpicheva

Introduction. To create a regulatory framework, including harmonized with European normative documents in terms of assessing passengers’ comfort, the standard of the enterprise STO RZD “Services in railway transport was developed. Rules for assessing the level of comfort of passengers on trains.” The objective of the study is to compare the indices of the comfort level of passengers, determined by the values of the accelerations acting on them, with the psychological sensations and physiological changes in the body arising in this case, depending on the rolling stock and the state of the track. Material and methods. The experiment using ECG monitoring devices was carried out in four groups of eleven people, six men and five women aged 30-55 years. Additionally, in each group, a psychological survey of 11 more passengers was carried out. All of them were staff members of the Russian Railways divisions. Results. When traveling on high-speed trains “Lastochka” and “Sapsan,” the respondents more often note drowsiness and an exhausted state’s progression. At the end of the trip, they often emphasize stiffness, discomfort, numbness, and numbness of the leg muscles, probably associated with an extended stay in a forced position in the absence of specific freedom movements. In the “lying” position, a person experiences less fatigue, which, according to the sensations, hardly differs from the conditions of a trip in a “sitting” position during short journeys. Regulatory changes in the cardiovascular system are manifested with the combined influence of uncanceled accelerations (the impact of centrifugal forces) and movement speed changes. Conclusion. Carrying out a questionnaire survey and physiological measurements of the dynamics of heart rate fluctuations on the investigated sections of the routes in combination with the obtained technical data on the nature of mobile rail vehicles’ movement confirm the absence of critical discomfort for passengers when traveling on passenger and high-speed trains. The calculated values of the average and constant comfort levels are consistent and do not require correction of the corresponding scales’ values.


Author(s):  
Luigi De Pari ◽  
Wojciech Z. Misiolek

In order to simulate copper extrusion more closely to industrial practices and to analyze the roots of the complicated issue of tube eccentricity, the material properties and the extrusion conditions were simulated using the finite element modeling (fem) software package, DEFORMTM-3D. This allowed prediction of stress, strain, strain rate, and temperature conditions within the billet during various processing conditions. These state variables were considered when ascertaining the influence of degree of billet upset and tool misalignment on tube eccentricity. It was found that under ideal upset conditions and perfect tool alignment, the tube eccentricity was minimized. If the piercer (or mandrel) was aligned with an initial angular or parallel misalignment that was still within tolerance the impact on eccentricity initially is minor in comparison to the eccentricity produced toward the end of extrusion, with the angular misalignment scenario being the more severe case. As a result, an angular misalignment is more detrimental than a parallel misalignment for tube preform eccentricity with the given forming parameters.


2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.


2020 ◽  
pp. 15-18
Author(s):  
Inna R. Kilmetova ◽  
◽  
Igor A. Rodin ◽  
Nazira I. Khayrullina ◽  
Nikolay G. Fenchenko ◽  
...  

Summary. The disbalanced feeding and the uneven distribution of micro- and macroelements in the environment leads to a trace element, in particular hypomelanosis. To accelerate the growth and preservation of young farm animals include in the diet of various biological additives and drugs, which include selenium. For stimulation of weight gain in the livestock industry, as well as for the prevention and treatment of pathological processes in addition to micro - and macrouse amino acids, primarily methionine. The aim of this work was to study the influence of composition of DAFS-25+Polizon on morpho-biochemical parameters of blood and functional state of the liver in fattening bulls of black-motley breed in the conditions of the Republic of Bashkortostan. Experiments using were conducted on bull-calves of black-motley breed of the properties in the properties age from 6 to 15 months. The first experimental group during the experiment was additionally given the composition of DAFS-25+Polizon at a dose of 2 mg/kg, the animals of the control group received a standard diet. To assess the impact of the composition DAFS-25+Polizon on metabolism cattle studied morphological and biochemical indicators of blood and conducted histological examination of the liver. It is established that the use of the composition of DAFS-25+Polizon at a dose of 2 mg/kg increases the number of erythrocytes and hemoglobin in the experimental group and reduces the amount of white blood cells. The serum content of total protein, phosphorus and calcium increases in the group of experimental animals. Microscopic examination of the liver revealed no changes in the structure of the organ and hepatocytes in the experimental group, whereas in the control group hemodynamic disorders and dystrophic changes in liver cells were observed. Thus, the use of the composition DAFS-25+Polizon at a dose of 2 mg/kg of live weight in fattening bulls black-and-white breed contributes to the increase of redox processes in the body, stimulation of metabolism, prevent the development of liver disorders of cellular mechanisms of metabolism, optimizes the structure of the liver, which generally provides higher productivity.


Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.


Author(s):  
Elena A. Beigel ◽  
Natalya G. Kuptsova ◽  
Elena V. Katamanova ◽  
Oksana V. Ushakova ◽  
Oleg L. Lakhman

Introduction. Occupational chronic obstructive pulmonary disease (COPD) is one of the leading nosological forms of occupational respiratory disease. Numerous studies have shown high effectiveness of the combination of indacaterol/glycopyrronium (Ultibro®breezhaler®) on the impact on clinical and functional indicators in the treatment of COPD in General practice.The aim of the investigation the case of occupational COPD with the analysis of the dynamics of functional indicators, tolerance to physical load and evaluation of the quality of life of workers engaged in aluminum production by using combination of indacaterol/glycopyrronium.Materials and methods. The random sampling method included 20 men, workers of aluminum production, with the established diagnosis of professional COPD at the age of 40 to 60 years. The survey was conducted (Borg scale, medical Research Council scale (mMRC) and COPD Assessment Test (CAT). Functional methods of studies were conducted: spirometry, body plethysmography, electrocardiography (ECG) and the six-minute stepper test (6-MST).Results. Against the background of 8 weeks of therapy, the volume of forced exhalation for 1 minute (FEV1) increased by 14.7% and amounted to 67.90% of the due values, the forced vital capacity of the lungs (FVC) increased by 11.3% and amounted to 76.95% of the due. According to the body plethysmography (BPG) is set to decrease in residual lung volume on average by 13.4% and static hyperinflation, confirmed by the decrease in functional residual volume (FRV) of 18.8%. During the study period increased physical activity of patients. The average difference between the distance traveled in the six-minute step test before and after treatment was 58.8 m. The analysis of personal data showed that the quality of life of patients improved, the total score in the questionnaire CAT at the beginning of the study was 16.9 points, and after 8 weeks decreased by 63% and amounted to 10.7 points.Conclusions: The Results indicate a positive effect of combination therapy with indacaterol/glycopyrronium on the course and progression of occupational COPD.


Author(s):  
Alizaman D. Gamon ◽  
Mariam Saidona Tagoranao

This study discusses the penetration of Islam in the Philippines, particularly the third wave of its expansion, which was brought by Sufi missionaries. It reinstates the historical relevance of Sufi ideas and approaches due to its contemporary relevance to the concept of social co-existence. The rational, intellectual and philosophical dimension of Islam is manifested in the cultural and traditional life of Muslim communities. The study also analyzes the impact of Muslim struggle for the development of Islamic institutions in the context of the secular state. The ongoing, unsettled debate between Islamic and government approaches to peace and development in Mindanao and Sulu continues unabated. Over the years, reforms were introduced, but in their midst, evidence of government biases and prejudices with regards to Islamic institutions have surfaced. Muslim leaders and intellectuals responded in the context of historical rights and freedom, but those views were often questioned as they are presumed to be incompatible with the national agenda for national unity. It was very recently that this incompatibility was readdressed giving support to having lasting peace and justice in Mindanao. The study argues that there have been substantial state-sponsored reforms which may contribute to the gradual advancement of Muslim communities. Though the path for the passage of Muslim concerns within the given condition is fragile and open to challenges, the study recognizes the prominence of inter-civilizational dialogue, from which the universal values of humanity will be embraced by both Muslim and non-Muslim policy makers. In addition, Muslim and non-Muslim communities in the Philippines need to embrace the universal principle of humanity and coexistence due to its relevance to the political stability and economic growth in the country.  Keywords: Muslims in the Philippines, Islamic institutions, Islamization, Muslim intellectuals, Reform. Abstrak Kajian ini mengkaji tentang kemasukan Islam, terutamanya gelombang ketiga perkembangannya, yang dibawa oleh para pendakwah sufi. Kajian itu mengembalikan semula sejarah penting tentang idea-idea dan pendekatan Sufi yang boleh digunapakai pada masa kini untuk mewujudkan keharmonian sosial di kalangan rakyat pelbagai agama. Pemahaman tentang Islam mempunyai pengaruh yang jelas terhadap kebudayaan dan tradisi Islam. Kajian ini juga menganalisis kesan perjuangan Muslim untuk pembangunan institusi Islam dalam konteks sebuah negara sekular. Perbahasan yang berterusan yang tidak menemukan penyelesaian antara pendekatan Islam dan pendekatan kerajaan untuk perdamaian serta pembangunan di Mindanao dan Sulu terus berlanjutan. Walaupun  bertahun-tahun pembaharuan telah dilakukan, namun terdapat bukti penolakan dan prasangka buruk kerajaan terhadap institusi Islam. Para pemimpin dan intelektual Muslim bertindak berdasarkan pada fakta sejarah dan hak kebebasan bersuara, namun pandangan mereka sering dipertikaikan kerana mereka dianggap tidak seiring dengan agenda dan perpaduan nasional. Baru-baru ini ketidakserasian ini mulai disuarakan semula untuk mendapat sokongan terhadap keamanan dan keadilan yang berterusan di Mindanao. Kajian ini mendapati bahawa terdapat pembaharuan yang dilakukan oleh pihak kerajaan yang boleh menyumbang ke arah  kemajuan masyarakat Islam secara beransur-ansur. Walaupun pendekatan bagi memenuhi hasrat orang Islam masih dalam keadaan yang rapuh dan penuh cabaran, namun kajian ini mengusulkan peripentingnya dialog antara peradaban dimana nilai-nilai universal manusia akan diperoleh dan dipegang oleh kedua-kedua pihak pembuat dasar iaitu  Islam dan bukan Islam. Di samping itu, umat Islam dan bukan Islam di Filipina perlu mengkaji dan mencontohi model keharmonian sosial Malaysia dan Singapura kerana kaitannya dengan kestabilan politik dan pertumbuhan ekonomi. Kata Kunci: Muslim di Filipina, institusi Islam, Islamisasi, intelektual Islam, Pembaharuan.


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