keywords stress
Recently Published Documents


TOTAL DOCUMENTS

54
(FIVE YEARS 34)

H-INDEX

2
(FIVE YEARS 0)

Author(s):  
Andrey Grabovskiy ◽  
Mykola А. Tkachuk ◽  
Natalia Domina ◽  
Ganna Tkachuk ◽  
Olha Ishchenko ◽  
...  

  In many constructions, their elements are in contact with nominally matching (congruent) surfaces. In reality, this contact is disturbed due to deviations in the shape of these surfaces from the nominal. To study the effect of this perturbation on the distribution of contact pressure, the analysis of the stress-strain state of the body system of punched sheet-die is carried out. The middle element of this system deviates from the nominally flat shape. This causes a change in the contact pressure distribution. The proportionality between the clamping force and the level of contact pressure is also lost. The reliability and accuracy of the results obtained by numerical calculation have been experimentally confirmed. Keywords: stress-strain state; contact pressure; contact interaction; method of variational inequalities; Kalker variational principle; finite element method


Author(s):  
Mykola M. Tkachuk

The paper describes the developed statistically averaged models of deformation of materials with a random network structure of differently oriented fibers. New methods of stress-strain analysis and micromacromechanical models of material deformation in the volume of bodies made of material with a network structure taking into account structural and physical nonlinearities have been created. These models are based on the micromechanics of network structures at the level of statistical sets of their chains. The novelty of approaches, models, methods and results is the creation of theoretical foundations for the analysis of the deformation of non-traditional network materials. Nonlinear mathematical models of material deformation in the form of a chaotic network structure of one-dimensional fragments are proposed, which are constructed involving fundamentally new approaches to the description of physical and mechanical properties at the micro level of statistical sets of fiber chains and spatial homogenization of their macroproperties. Compared to traditional models, they more adequately model the features of material deformation in the form of spatial chaotic and ordered network structures, as they do not involve a number of additional non-physical hypotheses. This creates fundamentally new opportunities not only for analyzing the properties of such materials, but also when creating new ones with specified properties. Using the created methods, models and research tools, the basis for solving a number of model and applied problems has been created. The nature of deformation of non-traditional materials with a network structure of one-dimensional elements is determined. The macro-properties of these materials are established on the basis of the developed micromechanical models, variational formulations and averaging methods. Keywords: stress-strain state, network structures, contact interaction, finite element method, contact pressure, machine parts, variational formulation


Author(s):  
Anton Vasiliev ◽  
Serhii Kutsenko ◽  
Mykola А. Tkachuk ◽  
Andrey Grabovskiy ◽  
Oleg Shatalov ◽  
...  

To study the effect of shock wave load on the body elements of vehicles, a setting has been developed that takes into account the mobile nature of this load. A specialized parametric finite-element model of the body layout has been created armored-carrier, taking into account the peculiarities of the studied process. The problem of determining the stress-strain state armored-hulls solved in static and dynamic formulation. The space-time distributions of components and characteristics of the stress-strain state of the investigated model armored-carrier of armored hulls are given. The results of research in the used formulations indicate the need to solve the problem in a complete dynamic formulation with account for plastic deformations. This  establishes a new methodology for the rational choice of engineering solutions. Keywords: stress-strain state; armored carrier; armored hulls; shock wave; moving load; sample; rational constructive decision


Author(s):  
Oleg Veretelnik ◽  
Mykola M. Tkachuk ◽  
Serhii Kravchenko ◽  
Mariia Saverska ◽  
Serhii Kutsenko ◽  
...  

Research and experimental studies of stress-strain state of discrete-continual hardened machine parts are presented in this work. This hardening method is distinguished by incorporation of numerous hard spots into the surface layer of one of the bodies. Meanwhile the other part is covered by a continuous corundum layer. Correspondingly, a network of microchannels for lubricant is formed between the bodies. Furthermore the contact loads are intensified in the vicinity of the harder material in the discrete zones. As a result the strength and durability of the loaded parts is increased. The technological parameters of the hardening process have great impact on the resulting characteristics. In particular, this concern the shape of the discrete hardening zones and the material properties of the corundum layer. These factors were varied in stress-strain analyses of the contacting bodies. The dependence of the stress-strain state characteristics on the varied parameters was established. The justified recommendations regarding the technological parameters of the discrete-continual hardening have been developed. Keywords: stress-strain state,  discrete-continual hardening,  contact interaction, finite element method, contact pressure, machine parts


2021 ◽  
Vol 1 ◽  
pp. 953-958
Author(s):  
Azmiati Fuadina ◽  
Mokhamad Arifin

AbstractHypertension is a disease of high blodd pressure in which the blooad pressure in the arteries exceeds normal limits. It is caused by various factors, such as increasing age, stress, unhealthy consumtion patterns, obesity, and jeredity. Stress is physical and psychological pressure that occurs on oneself and take place continuously. This literature review aimed determine the correlation between stress and hypertension in the community. The method used in teh study was a literature review, by accessing the Google Scholar and PubMed databases using the keywords “Stress” AND “Hypertension” AND “Society”. Participants in this study were public from young adults, middle adults, and old adults who had a P-Value of 0,000. The results of this study indicated that there was a relationship between stress and hypertension in the community, seen from the five articles that experienced stress as many as 204 respondents and had hypertension as much as 82%. This is a correlation between stress and hypertension in the community. It is hoped that it can provide further nursing intervensions in overcoming stress and hypertension problems in the community.Keywords: Stress; Hypertension; Public. AbstrakHipertensi adalah penyakit darah tinggi dimana tekanan darah dalam arteri melebihi batas normal. Hal ini disebabkan oleh berbagai faktor, seperti bertambahnya usiam stres, pola konsumsi yang tidak sehat, kegemukan, dan keturunan. Stres adalah suatu tekanan fisik dan psikis yang terjadi pada diri sendiri dan berlangsung secara terus menerus. Literature Review ini yaitu untuk mengetahui hubungan stres dengan hipertensi pada masyarakat. Metode yang digunakan dalam penelitian ini adalah literature review, dengan mengakses database Google Scholar dan Pubmed dengan menggunakan kata kunci “Stres” AND “Hipertensi” AND “Masyarakat”. Partisipan pada studi ini adalah masyarakat dari usia dewasa muda, dewasa menengah, dan dewasa tua yang didapatkan P-Value 0,000, diperoleh dengan menggunakan metode melalui cross sectional. Hasil penelitian ini menunjukan bahwa ada hubungan stres dengan hipertensi pada masyarakat, dilihat dari kelima artikel yang mengalami stres sebanyak 204 responden dan mengalami hipertensi sebanyak 82%. Hasil penelitian ini diketahui ada hubungan stres dengan hipertensi pada masyarakat, diharapkan dapat memberikan intervensi keperawatan lebih lanjut dalam mengatasi masalah stres dan hipertensi pada masyarakat.Kata kunci: Stres1; Hipertensi; Masyarakat


Author(s):  
Anvarjon Xakimov

Annotation: The deformation resistance properties of structural materials in the case of linear and flat stresses are given on the basis of experimental results. The method of estimating the mechanical properties of the material based on the initial deformation diagrams is described. Keywords: Stress, deformation, longitudinal force, internal pressure, stress state, deformation diagram, initial deformation, Yung modulus, Poisson's ratio, anisotropy, strength, yield strength


NSC Nursing ◽  
2021 ◽  
pp. 50-63
Author(s):  
Ika Murtiyarini ◽  
Imelda Imelda ◽  
Yuli Suryanti ◽  
Rosmaria Rosmaria

Introduction: Prenatal stress is often encountered but is rarely recognized and is considered not to affect pregnancy. Pregnancy has the potential to cause morbidity during pregnancy. In a study in Indonesia, 64.4% of pregnant women experienced severe stress and were at risk of causing preterm labour. One of the preventive measures during pregnancy to improve the health condition of the mother and baby is yoga. Prenatal yoga can prepare pregnant women physically, mentally, and spiritually to play a role in the delivery process. Materials and Methods: The current study is a quantitative study with a pre-experimental design with one group pretest-posttest without control to determine the effect of prenatal yoga on stress levels of pregnant women in the private midwives of Jambi City in 2020. The study population was 86 pregnant women; by purposive sampling, 30 pregnant women were taken. The time of the study was from March to November 2020. The data analysis used was univariate analysis and bivariate analysis with the Wilcoxon test. Results: In the initial assessment, most pregnant women experienced moderate stress levels; after prenatal yoga, most pregnant women experienced mild and average stress levels. Wilcoxon test results show that prenatal yoga has an effect on stress levels of pregnant women with a p-value of 0.0001 (<0.05). Conclusion: Prenatal yoga is effective for reducing stress in third-trimester pregnant women. Keywords: Stress, pregnant women, Prenatal yoga, Depression Anxiety and Stress Scale (DASS)


2021 ◽  
Vol 22 (1) ◽  
pp. 205-215
Author(s):  
Syed Mohammad Hilmi Syed Abdul Rahman ◽  
Annuar Ramadhon Kasa @Muhyiddin

Abstract Everyone could not escape from hardship in life whereby it may result heterogeny feelings including stress. Stress is one of a serious mental illness that can be suffered since childhood.  The lack of children control towards stress may result many negative impacts to their physical, emotion and mental. Therefore, Islam had place parents as one of children educator and mentor for their every single problem in life. The purpose of this research is to discuss several strategies in managing children stress in accordance to Islamic perspective. This article is a qualitative research which use documentation methodology for collecting data and thematic analysis for analyzing data. The data’s collected based on this research themes such as health, psychology, parenting education and early childhood education according to Islamic approach. This paper identified several convenient and suitable ways for children’s stress management according to Islamic views. Keywords: stress management, children, Islamic perspective.   Abstrak Setiap individu tidak terlepas daripada ujian dalam kehidupan yang akhirnya menimbulkan pelbagai perasaan termasuklah keadaan tertekan. Tekanan yang juga disebut sebagai stres merupakan masalah kesihatan mental yang serius sehingga boleh dihidapi sejak peringkat kanak-kanak lagi. Ketidakupayaan anak-anak dalam menguruskan stres boleh menimbulkan pelbagai implikasi negatif kepada fizikal, emosi dan mental. Oleh sebab itu, Islam memposisikan ibu bapa sebagai pendidik dan pembimbing kepada anak-anak dalam setiap urusan termasuklah menguruskan setiap permasalahan mereka. Tujuan kajian ini dijalankan adalah untuk membincangkan strategi mapan dalam menguruskan stres anak-anak menurut perspektif Islam. Artikel ini merupakan kajian kualitatif yang menggunakan metode dokumentasi bagi mengumpul data dan analisis tematik bagi menganalisis data. Data-data tersebut diambil berdasarkan tema berkaitan kajian seperti kesihatan, psikologi, pendidikan keibubapaan dan pendidikan awal kanak-kanak menurut pandangan Islam.  Hasil kajian ini juga telah mengenalpasti beberapa pengurusan stres yang sesuai diguna pakai oleh ibu bapa terhadap anak-anak mereka menurut pandangan Islam. Kata kunci: pengurusan stres, anak-anak, perspektif Islam.


2021 ◽  
Vol 6 (3) ◽  
pp. 281-284
Author(s):  
Shallu Chaudhary ◽  
Neha Atwal

Anaesthesia has emerged as one of the most stressful branches owing to the work it involves like emergency, critical care and other difficult patient situations. This occupational stress leads to the development of burnout syndrome among the anesthesiologists. This is characterized by emotional exhaustion, depersonalization and lack of personal accomplishments resulting in medical errors and deterioration of performance. A vast amount of literature is available listing the various causes of this syndrome. Appropriate stress managing strategies are advocated to reduce the stress sources. Keywords: Stress, Anesthesiologists, Anaesthesia


2021 ◽  
Vol 6 (2) ◽  
pp. 280-282
Author(s):  
Shallu Chaudhary ◽  
Major Amit Atwal

In our study, we presented a 48 year old female patient who developed stress cardiomyopathy after undergoing two major surgeries:- left nephrectomy followed by exploratory laparotomy with limited resection of colon with colostomy. Our patient had chest pain and dyspnea. ECG and ECHO findings were consistent with findings of stress cardiomyopathy. The Troponin I and BNP levels were also raised. Our patient developed left ventricular failure which was treated with injection lasix and injection morphine. Further management included beta-blockers, ACE inhibitors, diuretics. Our patient responded to the treatment and improved progressively. Keywords: Stress induced cardiomyopathy, reversible cardiomyopathy, Takotsubo cardiomyopathy.


Sign in / Sign up

Export Citation Format

Share Document