• 대한기계학회논문집A
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• 제27권4호
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• pp.515-523
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• 2003

Shape memory is physical phenomenon which a platically metal is restored to its original shape by a solid state phase change by heating. TiNi alloy the most effective material in the shape memory alloy(SMA). To study(measure) recovery stress of intelligent composite. Ti50-Ni50 shape memory matrix with prestrain SMA fiber. When SMA fiber of the intelligent composite is heated over austenite starting temperature(As) by electric heating. a recovery stress are generated. The recovery stress of the intelligent composite was measured by strain gage or photoelastic experiment. Measuring method of recovery stress by photoelastic experiment was developed in this research. It was certified that photoelastic experiment was more effective and more precise than strain gage method in the measurement of recovery stress.

• Journal of Biosystems Engineering
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• 제32권6호
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• pp.395-402
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• 2007

This study was carried out as basic researches to develop the leaf vegetable harvester. This study was conducted to investigate physical and rheological properties of bundled leaf vegetables with stem (Chinese leek, Crown daisy and Chamnamul) as test materials held and picked-up by a machine. Stress-strain behavior, stress relaxation, and strain recovery for the bundled materials were analyzed using simple Maxwell model. Physical and rheological properties of the materials were investigated by measuring rupture load, deformation and stress experimentally. Also, strain recovery time when unloading was measured using super high speed camera. Recorded recovery time for stress-strain behavior was0.026 s for Chinese leek with liner strain recovery, 0.046 s for Crown daisy and 0.05 s for Chamnamul with non-linear strain recovery. Furthermore, the strain recovery time for permanent deformation was 0.026 s, 0.046 s, and 0.05 s for Chinese Leek, Crown daisy and Chamnamul, respectively. Finally, strain recovery time and strain recovery ratio for the test materials were 0.17 s, 60.4% in Chinese leek, 0.12 s, 55.3% in Crown daisy, 0.15 s, 58.7% in Chamnamul. Here strain recovery time means that how fast the test materials are recovered from initial deformation and strain recovery ratio means how much the test materials are recovered from initial deformation. The above results show that the test materials can be held enough and moved by the belts.

• 대한인간공학회지
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• 제21권2호
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• pp.59-70
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• 2002

This paper is about the evaluation of stress response and recovery using biosignals and fuzzy theory. We caused mental stress by means of a coin-stacking task. During the experiment, 4 kinds of biosignals, including frontalis EMG, ECG, peripheral skin temperature and skin conductance level, were acquired. Then, the degree of stress was assessed by synthetically those signals using fuzzy inference. From the fuzzy inference result, the parameters (amount of physiological change / amount of imposed stress) and (time to 25% recovery), which represent response and recovery respectively, were derived. We made a two-dimensional point graph using the response parameter as an abscissa and the recovery parameter as an ordinate for each subject.

• 한국직업건강간호학회지
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• 제25권1호
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• pp.9-18
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• 2016

Purpose: This study was conducted to identify the factors affecting container terminal worker's recovery experience from job stress. Methods: The subjects were 299 workers from one S dock in P city. Data were collected from April 5 to June 5, 2015 and analyzed by SPSS/WIN 18.0 program using descriptive statistics, t-test, ANOVA, $Sheff{\acute{e}}$ test, Pearson's correlation coefficients, and logistic regression. Results: The mean scores of job stress, ego-resilience, and recovery experience from job stress were 47.18, 46.90, and 49.17 respectively. Recovery experience according to the general characteristics showed significant correlation between daily exercise. There was a significant negative correlation between recovery experience and job stress, and a positive correlation between recovery experience and ego-resilience. Recovery experience was 2.54 times higher for a high ego-resilience group than for a low ego-resilience group, and the group that exercised was 2.25 times higher, than the non-exercising group. The group with a low level of interpersonal conflict was 1.97 times higher, than a group with a high level of interpersonal conflict. Conclusion: Based on this study, intervention programs to increase ego-resilience, decrease interpersonal conflict, and encourage over 30-minute-daily exercise for in container terminal workers should be developed to improve recovery experience of job stress.

• 한국조경학회지
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• 제28권6호
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• pp.106-113
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• 2001

The purpose of this study is to find out the effect of recovery from psychological stress when watching plants indoors. As an instrument of measurement of psychological stress, Galvanic Skin Resistance(GSR) has been used because it has been convenient to read a psychological sign without a medical sense and an instrument. In order to make the conditions of stress and recovery, video programs have been made, and especially, the video program of recovery has consisted of three types-- types 1 of watching plants in a botanical garden, type 2 of watching very bush street, and type 3 of closing eyes naturally. The two groups of normal and the mentally handicapped persons have been participated in this experiment to compare the effect of recovery. As the result of this test, the rate of stress relief has been maximumly effected by watching the video program of plants. Between the two groups the recovery of stress has had better effects on the mentally handicapped than the normal one. And also it shows that the circumstances of emotional refinement is led by having plants in indoor. The result of this test has been turned out to be highly useful. It is desirable that a indoor worker, staying for a long time, contact with plants visually to keep healthy mental conditions. This study suggests that the surrounding conditions or the settings of circumstances play an important role for the emotional refinement of the groups of mentally han야capped persons as well as the normal person.

• 동서간호학연구지
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• 제23권1호
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• pp.86-95
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• 2017

Purpose: This study was conducted to investigate the effects of forest walking program on stress and recovery among schizophrenic patients in a closed ward. Methods: A non-equivalent control group pre-posttest design was used. The participants were composed of 36 patients with schizophrenia admitted in two psychiatric hospitals. The experimental group (n = 18) received the forest walking program twice a week with a total of 6 weeks. Results: The study results revealed that the forest walking program was effective on stress(${\chi}^2=34.11$, p<.001), subjective recovery(${\chi}^2=22.40$, p<.001) and clinical recovery(F=28.34, p<.001) of hospitalized patients with schizophrenia. Conclusion: The findings indicate that the forest walking program for schizophrenic patients in the closed ward can be an effective nursing intervention to reduce stress and improve recovery ability. We suggest that mental health nurses may adapt this program to help patients with schizophrenia in a closed ward.

• 자원리싸이클링
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• 제14권1호
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• pp.55-63
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• 2005

This study investigated the electrochemical recovery of palladium in a HCl solution that is used for palladium leaching. The high acidity of HCl solution and the low concentration of Pd ions increased the cathodic overpotential and reduced the limiting current density. Lowering the current density produced dense deposits; however, they were under high tensile stress. Raising the temperature affected both the densification and the stress, which enabled the attainment of dense Pd deposits under low stress. Lowering the current density and raising the temperature up to 70$^{\circ}C$ was recommended for the recovery of palladium as sound bulk Pd deposits. Current efficiency was over 85% at the initial stage of recovery may decrease the current efficiency, since a low Pd ion concentration results in a low limiting current density.

• 임상간호연구
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• 제20권2호
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• pp.256-266
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• 2014

Purpose: This study was done to identify the level of knowledge on and stress from delirium among recovery room nurses, and correlations between these factors. Methods: In this study, 125 nurses agreed to participate in the study were surveyed from October 8 to October 28, 2013. Data were analyzed using t-test, ANOVA, $Scheff{\grave{e}}$ test and Pearson correlation. Results: Average percentage of correct answers to questions about delirium was 81.9% and the mean score was 26.22 (${\pm}5.01$). The mean score for recovery room nurses' work stress from emergency delirium was 3.86 (${\pm}0.99$). Extent of knowledge on delirium significantly differed by age (F=15.017, p<.001), length of clinical experience (F=22.132, p<.001), length of recovery room experience (F=10.538, p<.001), education (F=3.312, p =.040), and marital status (t=4.107, p<.001). Stress from ED was significantly related to age (F=9.185, p<.001), clinical experience (F=7.077, p=.001), and marital status (t=-2.027, p =.045). Knowledge on delirium had a negative relationship with stress from delirium (r=-.514, p<.001). Conclusion: Results show that nurses gained knowledge of delirium from their own clinical experience indicating a need to develop educational programs to improve knowledge on delirium and plans to reduce stress from delirium for recovery room nurses.

• 대한금속재료학회지
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• 제48권3호
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• pp.203-209
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• 2010

An application of the instrumented indentation technique has been expanded from the measurements of hardness and elastic modulus to the analysis of residual stress. A slope of the indentation loading curve increases (or decreases) according to compressive (or tensile) residual stress. A theoretical equation has been established for quantifying residual stress from the slope change. However, a precise observation of the remnant indents is indispensible because the theoretical approach needs actual contact information. In addition, the conventional hardness test is still used for predicting the residual stress distribution of welded joints. Thus, we observed the three-dimensional morphologies of the remnant indents formed on artificial stress states and analyzed stress effects on morphological recovery of the indents. First, a depth recovery ratio, which has been regarded as a sensitive stress indicator, did not show a clear dependency with the residual stress. Thus an analysis on volumetric recovery was tried in this study and yielded a inverse proportional behavior with the residual stress. In addition, an elastic to plastic volume recovery ratio showed more significant correlation with the residual stress.

• 한국정밀공학회지
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• 제14권2호
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• pp.145-151
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• 1997

In this paper, we discuss the cathode ray tube(CRT) glass bulb stress and sagging recovery by the contact band pressure using finite element method. We analyzed the band pressure and stress using contact element method between band and bulb before and after banding process which was conducted to decrease the stress concentration using finite element method, and calculated sagging recovery. The analysis results were confirmed by experiments using strain gauge and sagging recovery test apparatus.