scholarly journals Devising a procedure for assessing the subgrade compaction degree based on the propagation rate of elastic waves

2021 ◽  
Vol 1 (5 (109)) ◽  
pp. 6-15
Author(s):  
Vitalii Kovalchuk ◽  
Ivan Kravets ◽  
Olga Nabochenko ◽  
Arthur Onyshchenko ◽  
Olexander Fedorenko ◽  
...  

This paper reports the analysis of the methods for estimating the technical condition of the subgrade underneath a constructed railroad track or road during its operation. The study results have proven that the issue related to monitoring and controlling high-quality compaction of a heterogeneous subgrade remains relevant and requires the construction of reliable experimental methods for assessing the subgrade degree of compaction. A procedure for determining the compaction of subgrade in the laboratory has been devised, based on inertial microcomputer technologies, which makes it possible to assess the degree of compaction of subgrade soils depending on the propagation rate of an impact's elastic waves. An experimental study has been performed into the propagation rate of elastic waves across a homogeneous subgrade made of coarse-grained sand and a heterogeneous subgrade made of coarse sand with a layer of clay in the middle of the prism. The study results established that the propagation rate of an elastic wave in a heterogeneous subgrade accepts a lower value than the rate of wave propagation in a homogeneous subgrade. Through the dynamic interpretation, by using a discriminant statistical analysis, the characteristic features have been defined in the distribution of accelerations in the body of the homogeneous and heterogeneous subgrade, depending on the degree of compaction, which would make it possible to monitor the state of the subgrade during operation. As the degree of the subgrade soil compaction affects the technical condition of roads

Author(s):  
А.С. Казицкая ◽  
Т.К. Ядыкина ◽  
М.С. Бугаева ◽  
А.Г. Жукова ◽  
Н.Н. Михайлова ◽  
...  

В условиях непрерывного воздействия неблагоприятных факторов окружающей и производственной среды на человека особую актуальность приобретает изучение механизмов, поддерживающих гомеостаз организма. Длительное поступление фторидов в организм приводит к формированию хронической фтористой интоксикации, патогенез которой вызывает многочисленные споры и дискуссии. До сих пор недостаточно внимания уделяется изучению висцеральной патологии, обусловленной нарушениями иммунного статуса в условиях воздействия на организм соединений фтора. Практически отсутствуют исследования по изучению иммунной реактивности, определяющей морфофункциональный характер ответной реакции печени на ранних стадиях развития фтористой интоксикации. Цель работы - изучение действий патофизиологических механизмов иммунной реактивности печени при субхроническом действии на организм соединений фтора. Методика. Опыты проведены на 210 лабораторных крысах-самцах массой 180-220 г., разделенных на 2 группы: контрольную (n=80) и группу животных с субхроническим действием фторида натрия (n=130). Экспериментальные животные в течение 12 нед имели свободный доступ к водному раствору фторида натрия (концентрация 10 мг/л, что составляет суточную дозу фтора 1,2 мг/кг массы тела). Для изучения иммунологических и биохимических показателей забирали кровь из хвостовой вены через 1, 3, 6, 9, 12 нед от начала эксперимента. Для оценки состояния гуморального звена иммунитета определяли уровень сывороточных иммуноглобулинов (IgA, IgG, IgM) иммуноферментным анализом с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск). Уровень сывороточных цитокинов: TNF-α, IL-1β, 2, 4, 6, 10 определяли на анализаторе Multiskan EX методом иммуноферментного анализа с использованием наборов «Вектор Бест» (Новосибирск). Подсчет общего количества лейкоцитов произведен классическим способом в камере Горяева, анализ лейкоцитарной формулы - в окрашенных мазках периферической крови. Метаболические изменения оценивали по активности ферментов в ткани печени: щелочной фосфатазы (ЩФ), аланин- и аспартатаминотрансфераз (АЛТ, АСТ), лактатдегидрогеназы (ЛДГ), гаммаглутамилтранспептидазы (γ-ГТ). Активность ферментов определяли унифицированными методами с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск) на фотометре PM-750 (Германия). Гистологические исследования печени осуществляли после декапитации крыс, проводимой под эфирным наркозом. Результаты. Показано, что субхроническое воздействие фторида натрия сопровождается формированием внутриклеточных и внутрисосудистых повреждений печени. Активация медиаторов воспаления и развитие иммунологических нарушений в динамике эксперимента способствуют формированию системной воспалительной реакции, которая приводит к появлению стойких морфологических нарушений в печени и изменению активности ферментов основных метаболических путей. Заключение. Полученные результаты могут быть использованы при разработке и проведении профилактических мероприятий в условиях воздействия на организм высоких концентраций фтора с последовательным применением детоксикационной, иммуномодуляторной и органопротекторной коррекции. Studying mechanisms, which maintain the body homeostasis, is particularly important in the conditions of continuous impact of adverse environmental and manufacturing factors. Long-term exposure to fluorides leads to chronic fluoric intoxication, the pathogenesis of which is a subject of multiple controversy and discussions. Not enough attention is still paid to elucidating the visceral pathology associated with fluorine-induced immune disorders. There are virtually no studies of immune reactions that define the morphofunctional nature of the liver response to early stages of fluoric intoxication. Aim. To study pathophysiological mechanisms of hepatic immune reactivity in subchronic exposure of the body to fluorine compounds. Methods. Experiments were performed on 210 male rats weighing 180-220 g. The animals were divided into two groups: 1) control (n=80) and 2) subchronic exposure to sodium fluoride (n=130). The rats had free access to a 10 mg/l aqueous solution of sodium fluoride (daily dose, 1.2 mg/kg body weight) for 12 weeks. Blood was withdrawn from the caudal vein at 1, 3, 6, 9, and 12 weeks of the experiment for immunological and biochemical tests. Histological study of the liver was performed after decapitation of rats under ether anesthesia. Results. The subchronic exposure to sodium fluoride was associated with intracellular and intravascular damage of the liver. Activation of inflammatory mediators and development of immunological disorders during the experiment contributed to a systemic inflammatory reaction, which resulted in persistent morphological injuries of the liver and changes in enzyme activities in major metabolic pathways. Conclusion. The study results can be used for development and implementation of preventive measures against the effects of high fluorine concentrations, which would include a successive use of detoxification, immunomodulation and organ protection.


2007 ◽  
Vol 539-543 ◽  
pp. 2928-2933 ◽  
Author(s):  
V.S. Yusupov ◽  
A.I. Milyaev ◽  
Galia F. Korznikova ◽  
Alexander V. Korznikov ◽  
J.K. Kovneristii

Results of experimental research into evolution of the structure and microhardness of the hard magnetic Fe-30Cr-8Co-0,7Ti-0,5V-0,7Si alloy during complex two-level loading (compression + torsion) in isothermal conditions at various temperatures in single-phase region are reported. It was revealed that the deformation leads to a strong refinement of initial coarse-grained structure in the whole volume of the sample, however the generated structure is non-uniform through the body of the sample. In an active zone of deformation, near to mobile head, there is a microcrystalline layer with a grain size of about 5 microns which thickness poorly depends on the formation. With removal from the active zone of deformation the grain size increases, and microhardness decreases.


2020 ◽  
Vol 45 (2) ◽  
pp. 40-48
Author(s):  
A. J. Atansuyi ◽  
U. C. Ihendu ◽  
C. A. Chineke

This study was conducted to determine the growth performance, correlation and regression estimates of seven-chicken strains in South-western Nigeria using a total of 300 day-old chicks. The birds were divided into seven groups based on their strain. The seven strains are Normal feather (NF), Fulani ecotype (FE), Frizzle feather (FF), naked neck (NN) and Transylvania indigenous strains while Hubbard and Marshal were meat-type exotic chickens. There were forty- five (45) unsexed day-old chicks in each strain except the Frizzle feather that were 30 in number. Completely randomized design (CRD) was used for the trial that lasted for 8 weeks. The birds were fed experimental diets ad libitum throughout the period of the study. Results showed that there were significant differences (p<0.05) in the initial and final weights of the birds. It was observed that exotic strains weighed heavier (3569.73gHB) than their indigenous counterparts (1391.11gNF). However, the Fulani ecotype weighed heaviest (1840.99g) among Nigeria indigenous strains during the experimental period. This showed that FE strains are generally heavy breed chicken and could be incorporated into a meat producing indigenous chicken if improved upon. The result of the correlation coefficients showed that a very strong, positive and highly significant (P<0.001) relationship existed between body weights and linear body measurements as most of the values are (>0.40). All the body parameter examined had significant (p<0.01) and direct relationship with the body weight. Shoulder-to-tail length (STL) had the highest coefficient of 0.98.The high correlation estimates obtained in this study could be as a result of pleiotropy, heterozygosity or linkage of genes in the birds. The three functions were highly significant (p<0.05) for all the parameters studied. This shows that the functions well described the parameters. On the basis of coefficient of determination (R ), the body weight of poultry birds at any age can be predicted most accurately with BRG using cubic function.


Author(s):  
Nageeb AGM Hassan ◽  
Sabrina Ait Gacem ◽  
Afnan Abdul-Hameed Al-Qaysi ◽  
Maryam Jaafar AlAani

Background: Most of individuals do not prefer consulting a physician when they suffer from mild to moderate pain or fever and they tend to get over the counter drugs (OTC) from the pharmacy. Non-steroidal anti-inflammatory (NSAIDs) consumption pattern and self-medication behavior is a common practice especially during adolescence. Many self-medication behaviors were observed from individuals especially students which use NSAIDs frequently and that might lead to some unwanted effects due to improper knowledge and awareness. Although NSAIDs are considered as safe medications in general, but serious side effects are still present and can affect different parts of the body. Objectives: Our study aims to assess the correlation between several types of pain and self-medication pattern of Paracetamol and NSAIDs among university students in UAE. Methods: This was a cross-sectional study that was conducted among individuals aged 17 years and above from different nationalities and specialties from June till July 2018. The data were obtained through a validated self-administrated questionnaire that was distributed as a hardcopy as well as online. Data collection took place in UAE universities targeting 345 university students. The data were analyzed using SPSS version 20 and the results were considered significant at the 0.05 level with a 95% Confidence interval. Results: The current study results show that (67%) of individuals use pain medications to relief pain associated with headache. The majority of individuals reported that they suffer from pain at least one day weekly (26.4%). The pain that mostly led individuals to take pain medications is headache and it is accounts for (67%). The most frequently used pain medication is Paracetamol (80.9%) followed by Ibuprofen, Mefenamic acid and Diclofenac (35.4%, 17.1% and 13.6%) respectively. It was observed that (28.4%) of individuals use more than one pain medication at the same time. The results show that there was a significant correlation between the intake of Mefenamic acid for pain and individuals that reported the use of pain medications for menstrual pain [p=0.000, OR: 5.223, 95% CI: 2.73 - 9.96]. The significant intake of Aspirin for back pain [p=0.020, OR: 3.239, 95% CI: 1.159 - 9.05] and Diclofenac for both muscles pain and back pain back pain [p=0.000, OR: 3.061, 95% CI: 1.792 - 5.228), p=0.000, OR: 3.037, 95% CI: 1.789 - 5.15 respectively] and Paracetamol for both toothache and fever [p=0.002, OR: 1.220, 95% CI: 1.120 - 1.32 and p=0.044, OR: 1.137, 95% CI: 1.027 - 1.259 respectively]. The following NSAIDs showed a significant correlation with the intake of pain medications for toothache: Aspirin [p=0.018, OR: 3.167, 95% CI: 1.171 - 8.56], Ibuprofen [p=0.004, OR: 1.618, 95% CI: 1.201 - 2.17] and Diclofenac [p=0.000, OR: 2.692, 95% CI: 1.591 - 4.55]. Only Paracetamol was found to have a significant correlation for the use during fever [p=0.044, OR: 1.137, 95% CI: 1.027 - 1.259] while other pain medications were found to have a negative correlation. Conclusion: The majority of respondents use the pain medications to relief headache and the most frequently used pain medication was Paracetamol. A significant correlation was observed between the intake of Mefenamic acid for pain and individuals that reported the use of pain medications for menstrual pain as well as Aspirin intake for back pain, Diclofenac for muscles pain and back pain. Only Paracetamol was found to have a significant correlation for the use during fever while other pain medications were found to have a negative correlation.


2021 ◽  
pp. 69-79
Author(s):  
V. V. GRITSAN ◽  

The article presents the results of surveys of 311 class IV hydraulic structures carried out in 2016-2020 in the Moscow region. All the reservoirs of the surveyed hydraulic units were classified according to their characteristic features, the technical condition of culverts and dams was assessed, there was established the safety level of both separate structures and hydraulic units as a whole. During the surveys, the technical parameters of the surveyed structures were established, the state of each structure and the hydraulic unit as a whole was assessed, a possibility of their accident and a risk level for the downstream areas were considered. At the same time, recommendations were developed for the elimination of serious damage and, with the help of an examination, the amount of the cost of the necessary repair work was determined. The paper also assesses the issues of the ecological state of the areas where the hydraulic units are located and the hydraulic units themselves as blocks of the ecological framework of the territories.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Chunhui Huo ◽  
Javaria Hameed ◽  
Muhammad Waqas Sadiq ◽  
Gadah Albasher ◽  
Wedad Alqahtani

PurposeThis paper aims to provide a valid insight into consumers' minds while considering word of mouth (WOM), brand image and uniqueness as independent variables while considering the tourism industry as the primary stakeholder.Design/methodology/approachThe study adopts qualitative research methods and data collected from 1,033 respondents using convenience sampling methodology. The data are collected from different tourists spots in China and Pakistan. The PROCESS macro was utilized in this study using SPSS version 25.0 to inspect the impacts by using Model 4 and the conditional effects indirectly by utilizing Model 14.FindingsCustomer's intimacy, search for novel and unexplored destinations highlight WOM interactions and perceived service value. Service value, interactional justice and professional attitude of hotel management mediated all the given relationships significantly. The brand image does not mediate any significant associations. Perceived service value and brand image predict customer's loyalty, and WOM is the direct measure of their intentions, and these variables are market trend indicators. A tourist's response toward different destinations is described in this study with comparative analysis of Chinese and Pakistani tourists. The study results showed a significantly positive relationship between hotel management professional behavior, customer's loyalty, customer's intimacy and WOM.Research limitations/implicationsThe recruited population might not be represented as the broader and larger visitor population, resulting in restricting establishing tactics. Moreover, this study's results provide significant insight into a tourism industry, hence providing a chance to manage customer loyalty better.Social, managerial and theoretical implicationsThis study contributes significantly to the body of knowledge and provides remarkable insight from the managerial perspective. Interactional justice results in significant value for hotel management directors and top management, front desk staff and operatives and front level employees and managers. Consumer sensitivity of fairness in interpersonal dealings calls for behavioral changes in frontline employees, especially those directly dealing with hotel visitors. Hotel staff and management should formulate a system to deal with the demands and needs of visitors. It should describe the rights and obligations of visitors and ensure that each customer is treated equally and with respect. Customers should be motivated to read the survey questionnaires kept in their rooms and offer their views on the services provided. This strategy might increase the customers' sense of empowerment and leading to notions of fairness in individual encounters.Originality/valueThis study provides an insight into the customer's minds while considering essential variables that include WOM, brand image, perceived service value and uniqueness.


2021 ◽  
Vol 13 (1) ◽  
pp. 68-77
Author(s):  
Igor Мarmut ◽  
◽  
Andriy Kashkanov ◽  
Vitaliy Kashkanov ◽  
◽  
...  

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. As an example, the study of the braking qualities of four-wheel drive cars on an inertial roller stand is considered. Diagnosing the technical condition of cars from the point of view of traffic safety is one of the most important problems. This is especially important for systems whose technical condition affects traffic safety: especially braking systems. Foreign and domestic experience testifies to the effectiveness of instrumental control. The diagnostic equipment includes roller stands, on which you can check the braking properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. Such stands allow you to reproduce the real speed and thermal modes of the brakes (especially those equipped with ABS). To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the rollers. The studies of wheel rolling on the stand rollers have been carried out by many authors since the 80s of the last century. However, all these studies were carried out on uniaxial stands and for mono-drive vehicles. Nowadays, a large number of passenger cars have four-wheel drive. Rolling of the wheels of such cars on rollers and their interaction has practically not been studied. Therefore, a return to the study of this issue is relevant. A power model of the system of interaction between the car and the stand has been developed, taking into account the design features of the stand and the design features of the car's suspension. The power model of the system under consideration contains the equilibrium equations of the body and two bridges and the equations of motion of the rollers and wheels of the car. Based on the results of the analysis of the acting forces in the "car-stand" system, the braking moments on the wheels M and the coefficients of the use of the load q during the braking tests of a 4x4 vehicle were determined. The obtained research results allowed to improve the theory of interaction of a car wheel with the rollers of an inertial diagnostic stand.


2016 ◽  
Vol 12 (5) ◽  
pp. 24
Author(s):  
Majed F. Mujalli ◽  
Maen Z. Zakarneh ◽  
Ala’a Kh. Abu Aloyoun

<p>The aim of the study was to investigate the common sports injuries among physical activities practitioners at the physical fitness centers in Jordan. Study sample consisted of (272) volunteered male (n=221) and female (n=51) (age 30±3). Researchers used a special form used to evaluate athletic injuries. After collecting and analyzing the data. Results showed that the most common sports injuries among sample of the study was muscular tears 27.7%, muscle spasm 20.7%, and tears ligament 20.2%. And the most exposed parts of the body to injury is the lumbar area 26.8%, elbows 16.9%, followed by shoulders 8.9%. Also the study results revealed that the most cusses of injuries was over training 24.14%. Poor warm-up 22.1% and bad technic 11.3%. Bodies-building was the most type of activities subjects to injury with 18.8%. Physical Fitness 6.6% and weight loss 27.7. Results also showed that physical therapy was the most means of treating injuries 54.14%, drugs therapy 33.3% and surgical intervention 4.2%. Also the study shows that males are more exposed to injuries than females.</p><p>Conclusions: These finding indicate that sports injures is part of physical</p><p>Activities participations, preventive measures should be taken by participant's the researchers recommended the need for physical and medical checkup before participation in physical activity at the physical fitness centers.</p>


2019 ◽  
Vol 47 (1) ◽  
pp. 37-47 ◽  
Author(s):  
Heather Moorefield-Lang

Purpose What happens when a librarian outgrows their maker learning location or transfers to a new library? The purpose of this study is to explore the planning process for second and/or new library makerspaces. Is the planning more intentional? Is there more focus on how the makerspace should be put together for the community served? Is the community further involved? This study will explore those questions and more. Design/methodology/approach Using content analysis, the perspectives of practicing librarians in the achievement of subsequent makerspaces are examined. Data include librarian interviews, an analysis using NVivo 11 through the lens of design thinking, and a final review using member checking by each research participant. Findings Makerspaces continue to grow in popularity in school and public/community libraries. What is unexplored is the moving from a first makerspace to the implementation of a second and/or new maker learning location. More intentional planning is involved. The community served by the library is further engaged in the planning. Study results illustrate the value that community insight and intentional planning play in the design and implementation of makerspaces. Originality/value Makerspaces in libraries continue to grow in popularity; in turn, the body of peer-reviewed, scholarly publications also continues to grow. Librarians in the field are beginning to move from their first to second makerspaces. This study investigates those perspectives. Much can be gained from the experiences of those who have implemented their second or third makerspace.


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