• Title/Summary/Keyword: couple

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Effect of pre-magneto-electro-mechanical loads and initial curvature on the free vibration characteristics of size-dependent beam

  • Arefi, M.
    • Structural Engineering and Mechanics
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    • v.71 no.1
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    • pp.37-43
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    • 2019
  • This paper studies application of modified couple stress theory and first order shear deformation theory to magneto-electro-mechanical vibration analysis of three-layered size-dependent curved beam. The curved beam is resting on Pasternak's foundation and is subjected to mechanical, magnetic and electrical loads. Size dependency is accounted by employing a small scale parameter based on modified couple stress theory. The magneto-electro-mechanical preloads are accounted in governing equations to obtain natural frequencies in terms of initial magneto-electro-mechanical loads. The analytical approach is applied to investigate the effect of some important parameters such as opening angle, initial electric and magnetic potentials, small scale parameter, and some geometric dimensionless parameters and direct and shear parameters of elastic foundation on the magneto-electro-elastic vibration responses.

Time Harmonic interactions in the axisymmetric behaviour of transversely isotropic thermoelastic solid using New M-CST

  • Lata, Parveen;Kaur, Harpreet
    • Coupled systems mechanics
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    • v.9 no.6
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    • pp.521-538
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    • 2020
  • The present study is concerned with the thermoelastic interactions in a two dimensional homogeneous, transversely isotropic thermoelastic solid with new modified couple stress theory without energy dissipation and with two temperatures in frequency domain. The time harmonic sources and Hankel transform technique have been employed to find the general solution to the field equations.Concentrated normal force, normal force over the circular region, thermal point source and thermal source over the circular region have been taken to illustrate the application of the approach. The components of displacements, stress, couple stress and conductive temperature distribution are obtained in the transformed domain. The resulting quantities are obtained in the physical domain by using numerical inversion technique. Numerically simulated results are depicted graphically to show the effect of angular frequency on the resulted quantities.

Stress-assisted oxidation behaviour of inconel 52M/316 austenitic stainless-steel dissimilar weld joints in a simulated pressurised water reactor

  • Xu, Youwei;Yang, Binhui;Shi, Yu
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3778-3787
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    • 2022
  • The stress-assisted oxidation behaviour of Inconel 52 M/316 austenitic stainless-steel (SS) dissimilar weld joints (DMWJ) in a simulated pressurised water reactor environment was investigated. A corrosion galvanic couple formed between the Inconel 52 M and 316 SS due to differences in their nonferrous metal content. The electric field from the corrosion couple attracted metal cations (e.g. Fe2+, Cr3+) to the Inconel 52 M that were deposited as FeCr2O4. An additional corrosion galvanic couple was generated due to variations in the plastic deformation of the DMWJ. The superposition of electric fields from the different couples resulted in ridge-like oxide depositions in the fusion zone.

Nonlinear oscillations of a composite microbeam reinforced with carbon nanotube based on the modified couple stress theory

  • M., Alimoradzadeh;S.D., Akbas
    • Coupled systems mechanics
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    • v.11 no.6
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    • pp.485-504
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    • 2022
  • This paper presents nonlinear oscillations of a carbon nanotube reinforced composite beam subjected to lateral harmonic load with damping effect based on the modified couple stress theory. As reinforcing phase, three different types of single walled carbon nanotubes distribution are considered through the thickness in polymeric matrix. The non-linear strain-displacement relationship is considered in the von Kármán nonlinearity. The governing nonlinear dynamic equation is derived with using of Hamilton's principle.The Galerkin's decomposition technique is utilized to discretize the governing nonlinear partial differential equation to nonlinear ordinary differential equation and then is solved by using of multiple time scale method. The frequency response equation and the forced vibration response of the system are obtained. Effects of patterns of reinforcement, volume fraction, excitation force and the length scale parameter on the nonlinear responses of the carbon nanotube reinforced composite beam are investigated.

A modified couple-stress magneto-thermoelastic solid with microtemperatures and gravity field

  • Samia M. Said;Elsayed M. Abd-Elaziz;Mohamed I.A. Othman
    • Structural Engineering and Mechanics
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    • v.87 no.5
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    • pp.475-485
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    • 2023
  • The present study deals with wave propagation in a modified couple-stress generalized thermoelastic solid under the effect of gravity and magnetic field. The problem is solved by a refined microtemperatures multi-phase-lags thermoelastic theory. The Fourier series and Laplace transforms will be used to obtain the general solution for any set of boundary conditions. Some comparisons have been shown in figures to estimate the effects of the gravity field, the magnetic field, and different theories of thermoelasticity in the presence of the hall current effect on all the physical quantities. Some particular cases of special interest have been deduced from the present investigation.

Interactions in transversely isotropic new modified couple stress solid due to Hall current, rotation, inclined load with energy dissipation

  • Parveen Lata;Harpreet Kaur
    • Coupled systems mechanics
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    • v.13 no.1
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    • pp.21-41
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    • 2024
  • This paper is concerned with the disturbances in a transversely isotropic new modified couple stress homogeneous thermoelastic rotating medium under the combined influence of Hall currents, magnetic fields, and mechanical sources represented by inclined loads. The application of Laplace and Fourier transform techniques are used for the derivation of analytical expressions for various physical quantities. As an application,the bounding surface is subjected to uniformly and linearly distributed force (mechanical force). Present model contains length scale parameters that can capture the size effects. Numerical inversion techniques has been used to provide insights into the system's behavior in the physical domain. The graphical representation of numerical simulated results has been presented to emphasize the impact of rotation and inclined line loads on the system, enhancing our understanding of the studied phenomena. Further research can extend this study to investigate additional complexities and real-world applications.

Perception of Internet Cyber Community Participants on Reconciliation of Divorced Couple (이혼 후 재결합에 대한 인터넷 사이버공동체 참여자들의 인식)

  • Lim, Choon-Hee
    • The Journal of the Korea Contents Association
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    • v.12 no.10
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    • pp.237-253
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    • 2012
  • The purpose of this study was to examine the perception of cyber community participants on reconciliation of divorced couple and find reasons for pros and cons concerning reconciliation after divorce. The data were collected through searching for website or Internet cafe related to 'reconciliation after divorce' on Internet. The contents of 7 cases for asking for advice on reuniting and opinions of cyber community participants on them were analyzed. Cyber community participants expressed their approval of divorced couple's reuniting for following reasons: 'strong motive for reunion', 'sexual relation with ex-partner', 'parental responsibility', 'regarding reconciliation as a better choice than remarriage', 'regarding as a good choice for child' etc. But cyber community members were opposed to divorced couple's reuniting for following reasons: 'doubt about real intention to reuniting', 'no self-reflection on previous marriage and ex-spouse', 'concern for recurrence of former marital conflict', 'reuniting only for child not for couple', 'no prior settlement of former marital conflict', 'no forgiveness and tolerance for ex-spouse', 'no reflection and change', 'no effort on ex-spouse's side' etc. Though these results were restrictive, this study identified issues surrounding reconciliation after divorce through asking and giving advices by anonymous members on cyberspace. These findings implied that we should take more interest in reconciliation as an realistic alternative marriage pattern after divorce and consider what is important to successful reuniting after divorce.

The Comparative Study of Family Dynamics between Families of Problem Students and of Normal Students (문제학생가족과 정상학생가족의 가족역동 비교연구)

  • 김윤희;문희자
    • Journal of Korean Academy of Nursing
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    • v.23 no.2
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    • pp.187-206
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    • 1993
  • The study was done to better understand problem behavior in high school students as described in family system theory, which explains the individual’s problem within the family interactions. The purpose of the study 1. To analyze the difference in the parents’ relationship as a couple between the two groups. 2. To analyze the difference in the parent-adolecent relationship between the two groups. 3. To analyze the difference in the family function (cohesion adaptability) between the two groups. The method of the study The staudy subjects consisted of a total of 176 families (528 persons), 109 high school students (End grade) with problem behavior and their parents (problem family group) ,and 69 high school students (same grade) with normal behavior and their parents (normal family group) residing in the Seoul area. Data were gathered from structured, self-reporting qestionaires which included a Couple Relation measurement (95 items) , Parent-Adolescent communication measurement (20 items), Family Cohesion Adaptability Scale (20 items) by DavidH. Olson et al., and a behavior evaluation tool. The results of the study 1. The results as related to the hypothesis were as follows. Hypothesis 1 : “satisfaction within The couple's relationship of the parents of problem family group will be lower than the normal family group was supported significantly(t=3.07, p=.005). Hypothesis 2: “The parent-adolescent relationship of the problem family group will be more negative and problematic than the normal family group” was supported significantly(t=4.06, p=.000). Hypothesis 3: “The family function (cohesion adaptability) of the problem family group will be lower than the normal family group" was supported significantly(t=2.20, p=.022) 2. The results of related analysis were as follows 1) Analysis of a causal relation between the couple’s relationship, the parent-adolescent relationship, family function and adolescent behavior showed that the Above 3 variables influenced adolescent behavior.. In cases where couple’s relation-ship, the parent-adolescent’s relationship, the family function are the better, their adolescent’s behavior is better. 2) Discriminant analysis of the research tool showed The discriminant ability of couple’s relationship tool was 75.57%, the Parent-Adolescent communication tool, 67.05, the family adaptability cohesion tool.67. 61%. In summary, interpersonal relationships in the family subsystems are interactive and their relation influences the behaviors. of adolescents in the family. Therefore, family therapy would be a more effective method than individual therapy, to resolve negative problem for adolscents, and the research tool used in this study are very useful for family system diagnosis and nursing intervention.

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Meta-analysis of the effects on family life education for couples in Korea (한국 부부교육 프로그램의 효과에 대한 메타분석)

  • Lee, Eun-yeong;Jang, Jin-Kyung
    • Journal of Family Relations
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    • v.22 no.4
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    • pp.181-204
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    • 2018
  • Objectives: The aim of this study is to integrate the results of the previous studies from 1900 to 2016 according to the types of dependent variables individually and statistically to obtain the results of the overall level of the marital education program I need to figure it out. In other words, the general and valid study on the overall effectiveness of the marriage education program will lead to more concluded conclusions and draw up an integrated and holistic conclusion about the effectiveness of the marriage education program. Method: The purpose of this study was to investigate the effect of married couples' education program on married couples' education program. The results of this study are as follows. First, Comprehensive Meta-Analysis. In other words, funnel plot, forest plot, and trim & fill were used to analyze all the variables related to the education of the couple, and homogeneity test After choosing an analytical model for the analysis, we calculated the 'standardized mean difference' effect size (d) that can compare different individual studies through the analytical model. The results of this study are as follows. Results: The purpose of this study was to investigate the overall effect size of domestic couples education programs after 1990, and to investigate the effect sizes of dependent variable types and program - related variables. First, the total effect size of the domestic marriage education program was close to the level of the large effect size and had a substantial and preventive effect. Self-esteem, communication, marital adjustment, emotion, and self control have a substantial and prophylactically significant change depending on the type of subordinate variables related to the marital education program But there was no change in origin family and life satisfaction. Third, as a result of the categorization of the dependent variable categorization of the Korean couple education program, it was found that the marital relations of the participant in the individual inner and the marital relations The effect was significant enough to change. Fourth, Korean couple education program was most effective when mixed age couples were participated in various family life cycle. Conclusions: Based on the results of this study, it is necessary to study more deeply about marital education program effect of marriage education for various special groups such as married couples who are in a crisis of divorce, . It also means that the results of the research for the last 30 years from 1900 to 2016 were comprehensively and systematically summarized through meta - analysis. The results of this study provide information on how to provide the most effective couples education programs for practitioners in the field. The result of this study will be the data of judgment about how to organize the marital education program for people of any ages and characteristics in the future.

The Effect of Burden of Caring Unmarried Adult Children on Depression of Employed Women: Mediating Effects of Couple Communication and Job Satisfaction (취업 여성의 미혼 성인자녀 돌봄 부담이 우울에 미치는 영향 : 부부의사소통과 일 만족도의 매개효과)

  • Cho, Ouk-Sun;Paik, Jina
    • Journal of Convergence for Information Technology
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    • v.8 no.6
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    • pp.293-303
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    • 2018
  • The purpose of this study is to explore the effect of burden of caring unmarried adult children on depression of employed women and to verify the mediating effects of couple communication and job satisfaction. For the purpose, the data from the fourth year Korean Longitudinal Survey of Women and Families on 586 employed women with baby boomer husbands and unmarried adult children were analyzed by using structure equation modeling. The found results are as follows. First, burden of caring unmarried adult children of employed women had a positive effect on their depression, while it had a negative effect on couple communication and job satisfaction. Second, couple communication of employed women influenced negatively on their depression and had a partial mediating effect on the relationship between burden of caring unmarried adult children and depression. Third, the effect of burden of caring unmarried adult children on depression of employed women was partly mediated by their job satisfaction. Further, the practical programs to enhance couple communication and job satisfaction, as well to reduce depression, were presented.