• Smart Structures and Systems
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• v.21 no.6
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• pp.715-725
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• 2018

Truss-Z (TZ) is an Extremely Modular System (EMS). Such systems allow for creation of structurally sound free-form structures, are comprised of as few types of modules as possible, and are not constrained by a regular tessellation of space. Their objective is to create spatial structures in given environments connecting given terminals without self-intersections and obstacle-intersections. TZ is a skeletal modular system for creating free-form pedestrian ramps and ramp networks. The previous research on TZ focused on global discrete geometric optimization of the spatial configuration of modules. This paper reports on the first attempts at structural optimization of the module for a single-branch TZ. The internal topology and the sizing of module beams are subject to optimization. An important challenge is that the module is to be universal: it must be designed for the worst case scenario, as defined by the module position within a TZ branch and the geometric configuration of the branch itself. There are four variations of each module, and the number of unique TZ configurations grows exponentially with the branch length. The aim is to obtain minimum-mass modules with the von Mises equivalent stress constrained under certain design load. The resulting modules are further evaluated also in terms of the typical structural criterion of compliance.

• Korean Journal of Adult Nursing
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• v.16 no.4
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• pp.556-565
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• 2004

Purpose: According to Lazarus & Folkman (1984), appraising a stressor as a threat is associated with negative psychological and physical adjustment, whereas appraising a stressor as a challenge is positive psychological and physical adjustment. This study examined how cognitive appraisal of PTCA(heart disease threat and treatment appraisal) related to the cardiac risk reduction behaviors(smoking cessation, low salt and low cholesterol diet, regular exercise and stress management) 6 weeks following discharge. Method: Data were collected from 50 subjects with successful primary PTCA. Result: Heart disease threat was negative related to treatment appraisal (r=-0.240, p=0.046). Psychological well-being was negative related to heart disease threat (r=-0.317, p=0.012) and positive related to treatment appraisal(r=0.402, p=0.002). The cardiac risk reduction behaviors score was negative related to heart disease threat(r= -0.296, p=0.018) and positive related to treatment appraisal(r=-0.291, p=0.020). Conclusion: More negative appraisal was related to lower the cardiac risk reduction behaviors score. But more positive appraisal was related to higher the cardiac risk reduction behaviors score. So, there is a need to develop the cognitive-behavioral intevention that increase the coping strategy to replace with positive appraisal.

• Structural Engineering and Mechanics
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• v.64 no.1
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• pp.59-69
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• 2017

The field of fracture mechanics has gained significance because of its ability to address the behaviour of cracks. Predicting the fracture properties of concrete based on experimental investigations is a challenge considering the quasi-brittle nature of concrete. So, there is a need for developing a standard numerical tool which predicts the fracture energy of concrete which is at par with experimental results. The present study is an attempt to evaluate the fracture energy and characteristic length for different grades of concrete using Concrete Damage Plasticity (CDP) model. Indian Standard and EUROCODE are used for the basic input parameters of concrete. Numerical evaluation is done using Finite Element Analysis Software ABAQUS/CAE. Hsu & Hsu and Saenz stress-strain models are adopted for the current study. Mesh sensitivity analysis is also carried to study the influence of type and size of elements on the overall accuracy of the solution. Different input parameters like dilatation angle, eccentricity are varied and their effect on fracture properties is addressed. The results indicated that the fracture properties of concrete for various grades can be accurately predicted without laboratory tests using CDP model.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1430-1434
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• 2005

We conducted two experiments to assess the effect of transfer from housing to grazing on stress hormone secretion in cattle using urine samples. In a preliminary experiment, urine samples were collected following an adrenocorticotrophic hormone (ACTH) challenge, and cortisol levels in urine were compared with the levels in plasma. In a second experiment, urinary cortisol was measured before and after the start of a grazing season in 6 Japanese Shorthorn cows, all of which had experienced grazing before. In experiment 1, urinary cortisol showed a pattern of changes similar to that of plasma with a 0.5-h temporal lag time, and the peak levels were 4 to 10 times higher than the basal levels. In experiment 2, the urinary cortisol levels in cows did not change after the cows were let out to pasture, with no decreases in body weight. This study suggests that the transfer from housing to grazing did not affect physiological responses to cause high excretion of urinary cortisol in grazing-experienced cattle using a non-invasive sampling method.

• Research in Community and Public Health Nursing
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• v.9 no.1
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• pp.21-29
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• 1998

This study was undertaken in order to examine the relationship of hardiness and health-promoting behavior and the effects of hardiness on stress-related physical symptoms. The subjects were 104 female nursing students of one college in Kongju. The instruments used for this study were a survey of general characteristics, hardiness(25 items), health-promoting behavior(44 items), and physical symptoms(35 items), Analysis of data was done by use of mean, Pearson correlation coefficient, stepwise regression and a hierarchical multiple regression with an SAS program. The results of this study are as follows. 1) Significant correlations between health -promoting behavior and subscales of hardiness, that is, control(r=-.35, P<.00l), commitment(r= -.29, P<.0l), and challenge(r= -.23, p<.05) were found. 2) Control was the highest factor predicting health -promoting behavior. 3) Main and buffering effects of hardiness on current physical symptoms were not found.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.270-275
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• 2004

Previous studies have shown that kimchi and kimchi-derived 3-(4'-hydroxyl-3', 5'-dimethoxyphenyl) propionic acid have anti-oxidative and hypolipidemic effects in rats and rabbits. This study was designed to investigate whether chemically synthesized 3-(4'-hydroxyl-3', 5' -dimethoxyphenyl) propionic acid (HDMPPA) may ameliorate oxidative stress through the regulation of nuclear factor KB (NFkB) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cells. Treatment of RAW 264.7 cells with 400 uM of HDMPPA significantly reduced LPS-stimulated nitric oxide (NO) production. Treatments with HDMPPA at 100 uM to 400 uM concentrations significantly elevated glutathione (GSH) level. However, cell viability and thiobarbituric acid-reactive substances (TBARS) concentrations were not affected by the concentrations of HDMPPA used. The specific DNA binding activities of NFKB, a transcription factor which is sensitive to oxidative stress, were not down-regulated by HDMPPA treatments. These results suggest that HDMPPA may have weak anti-oxidative activity against LPS challenge by scavenging NO and stimulating GSH production.

• Animal Bioscience
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• v.34 no.3_spc
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• pp.338-344
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• 2021

In the modern pig production, pigs are weaned at early age with immature intestine. Dietary and environmental factors challenge the intestine, specifically the jejunum, causing inflammation and oxidative stress followed by destruction of epithelial barrier and villus structures in the jejunum. Crypt cell proliferation increases to repair damages in the jejunum. Challenges to maintain the intestinal health have been shown to be related to changes in the profile of mucosa-associated microbiota in the jejunum of nursery pigs. All these processes can be quantified as biomarkers to determine status of intestinal health related to growth potential of nursery pigs. Nursery pigs with impaired intestinal health show reduced ability of nutrient digestion and thus reduced growth. A tremendous amount of research effort has been made to determine nutritional strategies to maintain or improve intestinal health and microbiota in nursery pigs. A large number of feed additives have been evaluated for their effectiveness on improving intestinal health and balancing intestinal microbiota in nursery pigs. Selected prebiotics, probiotics, postbiotics, and other bioactive compounds can be used in feeds to handle issues with intestinal health. Selection of these feed additives should aim modulating biomarkers indicating intestinal health. This review aims to define intestinal health and introduce examples of nutritional approaches to handle intestinal health in nursery pigs.

• Journal of Powder Materials
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• v.31 no.3
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• pp.213-219
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• 2024

Additive Manufacturing (AM) is a process that fabricates products by manufacturing materials according to a three-dimensional model. It has recently gained attention due to its environmental advantages, including reduced energy consumption and high material utilization rates. However, controlling defects such as melting issues and residual stress, which can occur during metal additive manufacturing, poses a challenge. The trial-and-error verification of these defects is both time-consuming and costly. Consequently, efforts have been made to develop phenomenological models that understand the influence of process variables on defects, and mechanical/ electrical/thermal properties of geometrically complex products. This paper introduces modeling techniques that can simulate the powder additive manufacturing process. The focus is on representative metal additive manufacturing processes such as Powder Bed Fusion (PBF), Direct Energy Deposition (DED), and Binder Jetting (BJ) method. To calculate thermal-stress history and the resulting deformations, modeling techniques based on Finite Element Method (FEM) are generally utilized. For simulating the movements and packing behavior of powders during powder classification, modeling techniques based on Discrete Element Method (DEM) are employed. Additionally, to simulate sintering and microstructural changes, techniques such as Monte Carlo (MC), Molecular Dynamics (MD), and Phase Field Modeling (PFM) are predominantly used.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.575-579
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• 2005

Urinary incontinence is the most common urinary symptom in children and causes considerable anxiety in children and parents. In most cases, there is no underlying organic pathology and the longterm prognosis is excellent. Despite these reassuring facts, children with wetting problems can be a challenge for primary pediatrician. This is probably because the problem is poorly understood, there is no readily identifiable medical pathology, and because treatment is usually time consuming and arduous. There is a great demand for treatment because wetting is an unpleasant symptom that can cause a stress and anxiety in the family. There may also be other coexisting problems such as urinary tract infection, constipation, soiling, and behavioral or emotional difficulties. Despite the frequency and vexing nature of voiding dysfunction, physicians may not always obtain a careful history to identify and to treat children properly with this condition. This article addresses the comprehensive diagnostic and therapeutic approach to such children.

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.616-622
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• 1994

Precise concept analysis has been neglected be-cause of a lack of understanding of its necessity and a lack of conceptual analytic knowledge. Concept analysis is the mental work of examining parts, phenomenon and the interrelated whole of a thing. Focus in this article is to extract the critical attributes of hardiness and make an operational delinition. The process of concept analysis is illustrated and documented using the analytic approach described by Walker and Avant (1983). To explore the explicit or implicit meanings of hardiness, existing literature was reviewed. The evolution of hardiness and the dictionary definitions were also added. Hardiness can be defined as follows : A condition of being inured to fatigue or hardship which has three subcomponents-challenge, control and commitment. Critical attributes of hardiness were extracted that may be used in naming the occurrence of the phenomenon. Model case, contrary case, borderline case and related case were described. Antecedents and consequences were explored. The defining critical attributes of hardiness are : 1. Resistance-hardiness involves resistance of stress or hardship. 2. Hardiness involves appraisal of change as a chance. 3. Hardiness implies interpretation of events and self as influential,. 4. Hardiness requires active involving reaction Implications for nursing and for further study are added.