• Title/Summary/Keyword: Physical Science Domain

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Modified Finite Volume Time Domain Method for Efficient Prediction of Radar Cross Section at High Frequencies

  • Chatterjee, Avijit;Myong, Rho-Shin
    • Journal of electromagnetic engineering and science
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    • v.8 no.3
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    • pp.100-109
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    • 2008
  • The finite volume time domain(FVTD) technique faces serious limitations in simulating electromagnetic scattering at high frequencies due to requirements related to discretization. A modified FVTD method is proposed for electrically large, perfectly conducting scatterers by partially incorporating a time-domain physical optics(PO) approximation for the surface current. Dominant specular returns in the modified FVTD method are modeled using a PO approximation of the surface current allowing for a much coarser discretization at high electrical sizes compared to the original FVTD scheme. This coarse discretization can be based on the minimum surface resolution required for a satisfactory numerical evaluation of the PO integral for the scattered far-field. Non-uniform discretization and spatial accuracy can also be used in the context of the modified FVTD method. The modified FVTD method is aimed at simulating electromagnetic scattering from geometries containing long smooth illuminated sections with respect to the incident wave. The computational efficiency of the modified FVTD method for higher electrical sizes are shown by solving two-dimensional test cases involving electromagnetic scattering from a circular cylinder and a symmetric airfoil.

A Study on the Educational Needs of the Kidney Transplant Patients and Educational Importance perceived by Their Nurses (신장이식 환자의 교육요구와 간호사가 지각하는 교육의 중요성 비교)

  • Ahn, Jae Hyun
    • Korean Journal of Adult Nursing
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    • v.12 no.4
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    • pp.678-689
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    • 2000
  • The purpose of this study was to explore the educational needs of kidney transplant patients and educational importance perceived by their nurses to develop a rehabilitational and educational program. Data were collected from January 29, 1999 to July 30, 1999 with interviews using a structured questionnaire. The subjects for this study were 173, of whom 107 were patients who had had a kidney transplant and had visited the out-patient department and 66 were transplant ward nurses who were taking care of the kidney transplant patients at six general hospitals located in Seoul. The questionnaire used for this study was developed by the investigator through a literature review and collected and modified by 11 professional personnel and 3 kidney transplant patients. The data were analyzed using the SAS program for numbers, percentiles, mean, standard deviation, t-test, ANOVA, and $Scheff{\acute{e}}$ test. The results were as follows; 1) In the patient group, the total mean score for educational needs was 154.61 and the item mean score was 3.96. In the nurses group, the total mean score for perceived educational importance was 166.26 and the item mean score was 4.26. In the nurses group, perceived educational needs were scored higher than by the patient group. With regard to domains, both patient and nurses group had the highest educational needs and perceived educational importance in the domain of physical condition and the top five items in the educational needs and perceived educational importance were also in the domain of physical condition. 2) In the patient group, women and the divorce/bereavement group had higher educational needs in the domain of nutritional management, those who had been admitted longer than 4 weeks from their kidney transplant time had higher educational needs in the domains of physical condition and those who were less than 4 years from their transplant had higher educational needs in the domain of follow-up care. In the nurses group, those who were married had higher perceived educational importance in the domain of physical condition.

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The Physical Interaction between Nucleotide-Binding Oligomerization Domain Containing 2 and Leucine-Rich Repeat Kinase 2

  • Jung, Ji-A;Park, Sangwook
    • Biomedical Science Letters
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    • v.26 no.1
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    • pp.47-50
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    • 2020
  • Recently, decades of robust researches on degenerative brain disorder have been highlighted on the interactive connection of gut and brain. In terms of inflammatory cytokine production, others have shown that Nucleotide-Binding Oligomerization Domain Containing 2 (NOD2) is involved with Leucine-Rich Repeat Kinase 2 (LRRK2). HEK293T cells were transiently co-transfected with Myc-tagged LRRK2 and Flag-tagged NOD2 and then followed by co-immunoprecipitation assay. In this study, we provide the novel finding of physical protein-protein interaction between NOD2 and LRRK2. G2019S variant has shown stronger interactions against NOD2 than those of wild type LRRK2. In an axis of NOD2-LRRK2 communication, it is believed to pave a new way in the understanding of the bidirectional molecular mechanism of brain disorder, including Parkinson's disease into gut inflammatory disease, including Crohn's disease.

A Study on the Educational Needs of Patients with Kidney Transplants and their Family Members after Discharge from Hospital (신장이식 환자와 가족의 퇴원후 교육요구)

  • 안재현;김남초
    • Journal of Korean Academy of Nursing
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    • v.29 no.6
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    • pp.1324-1335
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    • 1999
  • The purpose of this study was to explore the educational needs of patients with, kidney transplants and their family members to develop a rehabilitational and educational program. Data were collected from January 29, 1999 to April 20, 1999 with interviews using a structured questionnaire. There were 184 subjects in this study. of them, 107 were patients who had kidney transplants and had visited at the out-patient department of three general hospitals located in Seoul and 77 were family members. The questionnaire used for this study was developed by the investigator through a literature review and from data collected from 11 professional personnel and three kidney transplant patients and their families. The data were analyzed using the SAS program with t-test, ANOVA, Scheff test, Pearson correlation coefficient. The results are as follows; 1) In the patient group, total mean score for educational needs was 154.61 and the item mean score was 3.96. For the family group, total mean score for educational needs was 168.84 and the item mean score was 4.15. So in the family group, educational needs were scored higher than by the patient group. With regard to domains, both patient and family groups had as the highest educational needs, the domain of physical health and the top ten items in the educational needs were also in the domain of physical health. 2) In the patient group, women and the divorce/ bereavement group had higher educational needs in the domain of nutritional management, those who had been admitted longer than four weeks from their kidney transplant had higher educational needs in the domain of physical health and those who were less than 4 years from their transplant had higher educational needs in the domain of follow-up care. In the family group, those who were Catholics and had high school education had higher educational needs in the domain of nutritional management. 3) In the patient group, academic background was positively correlated(r=.208, p=.031) to educational needs.

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Effect of rotation and inclined load in a nonlocal magneto-thermoelastic solid with two temperature

  • Lata, Parveen;Singh, Sukhveer
    • Advances in materials Research
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    • v.11 no.1
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    • pp.23-39
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    • 2022
  • This work deals with the two-dimensional deformation in a homogeneous isotropic nonlocal magneto-thermoelastic solid with two temperatures under the effects of inclined load at different inclinations. The mathematical model has been formulated by subjecting the bounding surface to a concentrated load. The Laplace and Fourier transform techniques have been used for obtaining the solution to the problem in transformed domain. The expressions for nonlocal thermal stresses, displacements and temperature are obtained in the physical domain using a numerical inversion technique. The effects of nonlocal parameter, rotation and inclined load in the physical domain are depicted and illustrated graphically. The results obtained in this paper can be useful for the people who are working in the field of nonlocal thermoelasticity, nonlocal material science, physicists and new material designers. It is found that there is a significant difference due to presence and absence of nonlocal parameter.

A magneto-thermo-viscoelastic problem with fractional order strain under GN-II model

  • Deswal, Sunita;Kalkal, Kapil Kumar;Sheoran, Sandeep Singh
    • Structural Engineering and Mechanics
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    • v.63 no.1
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    • pp.89-102
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    • 2017
  • In this work, we present a theoretical framework to study the thermovisco-elastic responses of homogeneous, isotropic and perfectly conducting medium subjected to inclined load. Based on recently developed generalized thermoelasticity theory with fractional order strain, the two-dimensional governing equations are obtained in the context of generalized magnetothermo-viscoelasticity theory without energy dissipation. The Kelvin-Voigt model of linear viscoelasticity is employed to describe the viscoelastic nature of the material. The resulting formulation of the field equations is solved analytically in the Laplace and Fourier transform domain. On the application of inclined load at the surface of half-space, the analytical expressions for the normal displacement, strain, temperature, normal stress and tangential stress are derived in the joint-transformed domain. To restore the fields in physical domain, an appropriate numerical algorithm is used for the inversion of the Laplace and Fourier transforms. Finally, we have demonstrated the effect of magnetic field, viscosity, mechanical relaxation time, fractional order parameter and time on the physical fields in graphical form for copper material. Some special cases have also been deduced from the present investigation.

Effect of time harmonic sources on transversely isotropic thermoelastic thin circular plate

  • Lata, Parveen;Kaur, Iqbal
    • Geomechanics and Engineering
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    • v.19 no.1
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    • pp.29-36
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    • 2019
  • The present research deals with the deformation in transversely isotropic thin circular thermoelastic rotating plate due to time-harmonic sources. Frequency effect in the presence of rotation and two temperature is studied under thermally insulated as well as isothermal boundaries. The Hankel transform technique is used to find a solution to the problem. The displacement components, stress components, and conductive temperature distribution with the radial distance are computed in the transformed domain and further calculated in the physical domain using numerical inversion techniques. Some specific cases are also figured out from the current research.

Relationship among Pro-environmental Attitude, Behavior to Decrease Exposure, Knowledge of Endocrine Disruptors, and Obesity-related Profiles in Nursing Students (간호대학생들의 환경친화적 태도, 노출저감화 행동, 내분비계 장애물질에 대한 지식과 비만의 관련성 연구)

  • Kim, Min A
    • Journal of Korean Biological Nursing Science
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    • v.18 no.3
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    • pp.160-168
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    • 2016
  • Purpose: This study was conducted to examine the pro-environmental attitude (actual commitment domain, verbal commitment domain, affect domain), behavior to decreased exposure and knowledge of endocrine disruptors by obesity -related profiles (BMI, body fat percentage, visceral fat percentage, skeletal muscle mass percentage, waist circumference, waist-hip ratio). Methods: A cross-sectional study was conducted with 102 nursing students. Data were collected from November to December, 2015 using self-report questionnaires and physical measurements. Data were analyzed using t-test, Pearson correlation and coefficients with SPSS 18.0. Results: The study results showed that actual commitment domain of pro-environmental attitude and behavior to decreased exposure level on endocrine disruptors were significantly related to visceral fat percentage. Actual commitment domain of a pro-environmental attitude was significantly related to body fat percentage. Pro-environmental attitude was significantly related to the behavior to decreased exposure level on endocrine disruptors and knowledge thereof. Conclusion: These findings suggest that visceral fat and body fat percentages were significantly related to the actual commitment domain of a pro-environmental attitude. Therefore, a replication study is recommended to understand the connection between endocrine disruptors and obesity. In addition, developing an education program about endocrine disruptors for nursing students is recommended. In particular, a pro-environmental attitude, especially on actual commitment domain, could be involved as an education program.

A Component Model for Managing Covid-19 Crisis

  • Taweel, Faris M.
    • International Journal of Computer Science & Network Security
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    • v.21 no.7
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    • pp.365-373
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    • 2021
  • Covid-19 posed a serious threat to public health worldwide, especially in the absence of vaccines or medicines. The only viable strategies to combat a virus with a high infection rate were to apply lock-down strategies, transport ban, social and physical distancing. In this work, we provide a domain-specific component model for crisis management. The model allows for building a plan for managing Covid-19 crisis and use the plan as a template to generate a system specific for managing that crisis. The crisis component model is derived from X-MAN II, a generic component model that we have developed for the aircraft industry

Influence of Illumination on Domain Switching and Photovoltaic Current in Poled $(Pb_{1x}La_x)TiO_3$ Freeoelectric Ceramics

  • Park, Si-Kyung;Park, Dong-Gu;Kim, Sung-Ryul
    • The Korean Journal of Ceramics
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    • v.6 no.3
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    • pp.267-271
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    • 2000
  • The influence of photoexcited nonequilibrium carriers on domain switching and photovoltaic current was investigated in two kinds of poled La-modified PbTiO$_3$ferroelectric ceramics, (Pb$_{0.85}$La$_{0.15}$)TiO$_3$and (Pb$_{0.76}$La$_{0.24}$)TiO$_3$, under illumination in the absence of external electric field. Both photovoltaic current and cumulative AE event counts increased with illumination time. The observed nonsteady-state photovoltaic current could be explained on the basis of the cycles of a series of physical events consisting the establishment of space charge field by photoexcited carriers trapped at the grain boundaries, the photoinduced domain switching, and the increase in the remanent polarization. An analysis of energy distribution of the observed AE signals also revealed that the space charge field in (Pb$_{0.85}$La$_{0.15}$)TiO$_3$allowed both 18$0^{\circ}C$ and 90$^{\circ}$domains to be switched during illumination.

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