• Journal of Hydrogen and New Energy
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• v.27 no.1
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• pp.42-48
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• 2016

This study presents an experiment investigation on natural convection heat transfer of air-cooling Proton exchange membrane fuel cells (PEMFCs) in a enclosure system for unmanned aerial vehicles (UAVs). Considered are replacing fuel cell stack with Aluminum block for heat generating inside a enclosure chamber. The volume ratio of fuel cell stack and chamber for simulation to the actual size of aerial vehicle is 1 to 15. The parameters considered for experimental study are the environmental temperature range from $25^{\circ}C$ to $-60^{\circ}C$ and the block heat input of 10 W, 20 W and 30 W. Effect of the thermal conductivity of the block and power level on heat transfer in the chamber are investigated. Experimental results illustrate the temperature rise at various locations inside the chamber as dependent upon heat input of fuel cell stack and environmental temperature. From the results, dimensionless correlation in natural convection was proposed with Nusselt number and Rayleigh number for designing air-cooling PEMFC powered high altitude long endurance (HALE) UAV.

• Integrative Medicine Research
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• v.6 no.4
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• pp.388-394
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• 2017

Background: The present study optimized ultrasound-assisted extraction conditions to maximize extraction yields of glycyrrhizic acid from licorice. Methods: The optimal extraction temperature ($X_1$), extraction time ($X_2$), and methanol concentration ($X_3$) were identified using response surface methodology (RSM). A central composite design (CCD) was used for experimental design and analysis of the results to obtain the optimal processing parameters. Results: Statistical analyses revealed that three variables and the quadratic of $X_1$, $X_2$, and $X_3$ had significant effects on the yields and were followed by significant interaction effects between the variables of $X_2$ and $X_3$ (p<0.01). A 3D response surface plot and contour plots derived from the mathematical models were applied to determine the optimal conditions. The optimum ultrasound-assisted extraction conditions were as follows: extraction temperature, $69^{\circ}C$; extraction time, 34?min; and methanol concentration, 57%. Under these conditions, the experimental yield of glycyrrhizic acid was 3.414%, which agreed closely with the predicted value (3.406%). Conclusion: The experimental values agreed with those predicted by RSM models, thus indicating the suitability of the model employed and the success of RSM in optimizing the extraction conditions.

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.115-124
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• 2022

Emerging evidence has shown that RNA-binding proteins (RBPs) dynamically regulate all aspects of RNA in cells and involve in major biological processes of RNA, including splicing, modification, transport, transcription and degradation. RBPs, as powerful and versatile regulatory molecule, are essential to maintain cellular homeostasis. Perturbation of RNA-protein interactions and aberration of RBPs function is associated with diverse diseases, such as cancer, autoimmune disease, and neurological disorders. Therefore, it is crucial to systematically investigate the RNA-binding proteome for understanding interactions of RNA with proteins. Thanks to the development of the mass spectrometry, a variety of proteome-wide methods have been explored to define comprehensively RNA-protein interactions in recent years and thereby contributed to speeding up the study of RNA biology. In this review, we systematically described these methods and summarized the advantages and disadvantages of each method.

• Journal of Korean Elementary Science Education
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• v.32 no.3
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• pp.285-297
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• 2013

The purpose of this research is to find the effect of the lesson using open-inquiry report Lubric on open-inquiry standard and science process skill; to find the change of cognition on open-inquiry for elementary school 5th grade students. Two classes (elementary school 5th grade) were selected which located in a small and medium-sized city for this research and they were separated as an experimental group and a comparative group. Open-inquiry lesson was done by referring teaching method which introduced through the curriculum. The procedure was understanding about open-inquiry, making open-inquiry subject, planning, and performing inquiry, mid-term, performing inquiry, making a report, presentation, and evaluation. Open-inquiry report Lubric which developed by Sook-Kyung Kim et al. (2010) was provided to the experimental group. Comparative group was instructed by using open-inquiry report which introduced to the elementary school 5th grade science text book. Interview paper was developed in order to check out the effect of the research by using a test paper of science process skill. The following could be found out through the research. After open-inquiry lesson, 10 open-inquiry reports(5 reports from experimental group, 5 reports from comparative group) have been drawn at random as samples from the total 62 sets (30 reports from experimental group, 32 reports from comparative group) and evaluated by a researcher and two elementary school teachers who have master degree. The reliability of the 3 scorers was 0.923 of mean correlation coefficient. And then the researcher evaluated all open-inquiry reports. The average score of open-inquiry report was 66.78 for experimental group, 54.27 for comparative group, respectively. And there was a significant difference at p<0.05 level as a result of the t-test. The experimental group rated high at p<0.05 level according to the analysis of post-science process skill test. According to the result of survey, both experimental group and comparative group had understood open-inquiry activity. It was especially rated high for experimental group on understanding scientific inquiry process, interest and satisfaction in open-inquiry and re-participation rate. By interviewing experimental group, it is recognized that the students utilized Lubric very well through the overall process. Finally, self-evaluation was done during open-inquiry activity and it was reported that the students gained more knowledge about science and changed to positive about science. As a result, the lesson using open-inquiry report Lubric was effective for students to improve writing skill of an open-inquiry report and science process skill and finally changed the cognition to positive about open-inquiry lesson.

• Journal of Korean Clinical Nursing Research
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• v.14 no.2
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• pp.115-126
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• 2008

Purpose: This study was aimed to develop an aromatherapy hand massage program, and evaluate the effects of aromatherapy hand massage on cognitive function, sleep disturbance and problematic behaviors of elderly with dementia. Method: The research design was a nonequivalent control group non-synchronized quasiexperimental study. Aromatherapy hand massage was administrated to experimental groupI for 2 weeks, jojoba oil massage were administrated to experimental groupII for 2 weeks, and no treatment for control group for 2 weeks. Data were analyzed using the $x^2-test$, ANOVA, ANCOVA and $Scheff{\acute{e}}$ test in the SPSS 12.0 program. Results: Experimental group I showed significant changes in sleep disturbance and problematic behaviors compared to those in experimental groupII or control group. Conclusion: Aromatherapy hand massage program is found effective on sleep disturbance and problematic behaviors of elderly with dementia.

• Journal of International Academy of Physical Therapy Research
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• v.2 no.2
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• pp.301-307
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• 2011

The purpose of this study was an determine whether elastic band on treadmill training might effect the chest expansion and pulmonary function of the 20's men. 40 subjects with experimental group(male: 20) and control group(male: 20) was participated in experiment. During four weeks, each group participated thirty minutes for three times per week. Subjects were assessed using pre-value and post-value measurement chest length(chest length for resting, chest expansion) and pulmonary function(forced vital capacity, forced expiratory volume at one second, FEV1/FVC, peak expiratory flow, vital capacity, tidal volume, expiratory reserve volume, inspiratory reserve volume) by the CardioTouch 3000S(BIONET, USA). These findings suggest that experimental group can be used to improve chest expansion, pulmonary function than control group. In comparison of both groups, post-test was more improved in experimental group. In conclusion, experimental group helped improving function of pulmonary volume and respiratory muscle, and thus it indicates that the functions will be more improved through the continued respiratory exercise program.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.311-317
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• 2015

It is difficulty to calculate velocity circulation in centrifugal pump impeller outlet accurately. Velocity circulations of a double-blade pump impeller outlet were calculated with Stodola formula, Weisner formula and Stechkin formula. Simultaneously, the internal flow of impeller for the double-blade pump were measured with PIV technology and average velocity circulations at the 0.8, 1.0 and 1.2 times of design flow were obtained. All the experimental values were compared with the above calculation values at the three conditions. The results show that calculation values of velocity circulations with Weisner formula is close to the experimental values. On the basis of the above, velocity circulations of impeller outlet were corrected. The results of experimental verification show that the corrected calculation errors, whose maximum error is 3.65%, are greatly reduced than the uncorrected calculation errors. The research results could provide good references for establishment of theoretical head and multi-condition hydraulic optimization of double-blade pumps.

• Journal of Welding and Joining
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• v.29 no.4
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• pp.73-79
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• 2011

Friction stir welding (FSW) is a solid state joining method patented in 1991 by The Welding Institute (TWI). It is widely used for joining light metals such as Al and Mg alloys. Foreign railway vehicle manufacturing companies have been applying FSW to car body welding, but domestic companies are in the beginning of feasibility study. Therefore, lots of experimental and analytical study is needed. In this study, three-dimensional finite element modeling of the friction stir welding of two Al6061-T6 plates was carried out. And temperature field and residual stresses were obtained and compared to experimental results in the literature. It is found the analytic thermal field is in a good agreement with the experimental results, but there are some differences between numerical and experimental residual stresses.

• Steel and Composite Structures
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• v.12 no.6
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• pp.465-489
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• 2012

Residual stresses play important role for design of steel structural members. Cold formed sections usually have residual stresses caused by roll forming. When compared to stresses caused by the working load, especially for compressed members, the effects of residual stresses can be favorable or unfavorable depending on magnitude, orientation and distribution of these stresses. The research presented in this paper includes experimental investigations of residual stresses, initial imperfections and material properties on cold formed carbon steel open cross sections. Experimental results have been compared to results obtained in similar tests with stainless and high strength steel cross sections. Theoretical and experimental research, conducted for cold formed open cross sections, are important for design of axially compressed members. This paper presents two methods of residual stresses investigation: magnetic method and method of pre-drilled holes and obtained results have been compared with results of residual stresses from other authors.

• The Korean Journal of Rehabilitation Nursing
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• v.3 no.2
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• pp.154-168
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• 2000

This study was done to analyze the trends of research on stroke in Korea, to suggest future direction, for research on stroke. This article reviewed 75 nursing research papers on stroke done since 1990 to 2000 by examining them according to the period of publication or presentation, research design, type of subjects, measurement variables, the intervention outcome of experimental research, and theme of qualitative research. The research were as follows : 1. 26 of 75 studies were composed of master thesis and dissertation of graduate school. There were 53 nonexperimental research, 15 experimental research, and 7 qualitative studies design. 2. Stroke patients subject' Characteristic were 44 and Family and Spouses of caregiver support were 28 of total studies. 3. Most measurement instruments used for research were translated and redesigned it into Korean that developed by foreigners, and development measurement instruments used Kang's ADL. 4. Family support and Social support was shown the frequently among correlational research. 5. Methodological research were development of an evaluation tool for the quality of nursing care in stroke patients, caregiver support of development of nursing intervention list, and Home care Nursing Intervention protocol, and development of client selection criteria based on the needs of services to be offered. 6. The experimental research of intervention were mostly education nursing intervention, rehabilitation program on functional recovery, support nursing intervention, and applying a home care protocol on the nursing care intervention. 7. Theme of qualitative research were family experience, home care in family experience, soobal experience, illness experience, hope of Stroke patients and so on. Phenomenologic methodology and Granded Theory was designed of Qualitative research. On the basis of the above finding the following recommendations are made: 1. It's necessary to develop a reliable and variable measurement tool for stroke patients and family care of stroke patients. 2. It's necessary to study the comparison of Nursing Studies of stroke research abroad, the replication to establish the effect of nursing intervention stroke patients and family care of stroke patients.