• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.217-226
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• 2019

Optimum engineering methods for bank protection were classified based on steepness of bank slope and an existence of waterfront facility in the floodplain, and a new concept of eco-hybrid rolling mat method which could be applicable for the unfitted cases with previously developed countermeasures was suggested in this study. The eco-hybrid rolling mat method can be constructed while maintaining the river environment and ecosystem that does not interfere with the ground and slopes, when bank erosion occurs, it is an economical and efficient construction method that can protect the revetment and the bank slope immediately. The developed eco-hybrid rolling mat method was verified for the designed structure, system, function and effect based on large-scale river experiments including field exposure and decomposition test. As a result, the normal operation and effect of the rolling mat ted under low and high velocity conditions were confirmed with respect to bank protection. The effect of bank erosion prevention was quantitatively validated by sediment concentration monitoring and analysis, and the product specification of the eco-hybrid rolling mat was presented based on the standardized mat applied in real-scale tests.

• Journal of Hospice and Palliative Care
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• v.7 no.2
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• pp.179-188
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• 2004

Purpose: The purpose of this study was to investigate the degree of fatigue and its related factors in cancer patients during chemotherapy. Methods: The subjects of this study consisted of 90 patients over 20 years old who were receiving chemotherapy at the injection room of the o.p.d. and ward admission care unit in a University hospital located in Gwang-ju city and data were collected from August 8th to October 2nd, 2002. Collected data were analysed using SPSS v 10.0. to obtain summary statistics for the descriptive analysis, t-test, ANOVA, pearson correlation, and multiple regression. Results: 1. Fatigue of the subjects was significantly correlated with physical distress score. and 6 items of subscale those were nausea, vomiting, anorexia, pain, and immobility, showed statistically significant correlation. 2. Fatigue of the subjects showed statistically significant differences according to a nap satisfaction. Fatigue of the subjects was significantly correlated with mood state, Also, all 5 items of subscale, which are those were anxiety, confusion, depression, energy, and anger showed statistically significant correlations. 3. Fatigue of the subjects showed statistically significant differences according to metastasis, chemotherapy cycle, post operation existence, post radiation therapy existence. There were significant negative correlation between fatigue and hematocrit and fatigue and weight change. There was no significant correlation between fatigue and spiritual well-being state. With the result to multiple regression, Immobility, Anorexia, Anger explained fatigue by, pain, and immobility showed statistically significant correlation.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.645-652
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• 1996

Selective catalytic oxidation of $H_2S$ to elemental sulfur using $TiO_2/SiO_2$ catalysts was investigated in this study. The reaction test with pure $TiS_2$ and $Ti(SO_4)_2$ and cyclic temperature operation revealed that $TiO_2$ had a good resistance to sulfation and sulfidation, which are known as the main cause of catalytic deactivation in sulfur recovery process. With the increase of $TiO_2$ loading amount in $TiO_2/SiO_2$ catalysts, the conversion of $H_2S$ increased and the selectivity of elemental sulfur was very slightly decreased. As the ratio of $O_2/H_2S$ increased, the selectivity to elemental sulfur was drastically decreased. In the presence of 10 vol.% water vapor to a stoichiometric mixture of $H_2S$ and $O_2$($H_2S$= 5 vol.% O=2.5 vol.% ), both activity and selectivity of 10 wt.% $TiO_2/SiO_2$ catalyst are decreased, but it still showed more than 80% of sulfur yield.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.495-501
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• 2016

Mineral oil has been widely used as an insulating oil for electrical transformers for a long time, but the necessity of employing new insulation oil such as vegetable oil has been increased due to urgent needs for the biodegradability when it leaks and also for the thermal stability at a higher operation temperature. Although specific periods are required between the production and consumption, there are still short of the data to prove the insulation oils' storage stability depending upon various circumstances and their resources. Thus, this paper demonstrates the insulation oils' oxidation characteristics of both mineral and vegetable oils when each was exposed to different environments for 12 weeks. From this test, some properties including total acid number, water content and dielectric breakdown were changed under specific conditions and resources. Vegetable oils showed higher hydrophilicity and water saturation than those of mineral oils due to their molecular compositions. Under sunlight exposure condition, all insulation oils oxidized and changed their properties when exposing to the direct light, regardless of the resource used.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.110-117
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• 1998

A packed-bed reactor with immobilized transglucosidase (TG) was operated to test the possibility of continuous production of isomaltooligosaccharides (IMO) and the effect of concentration and feed rate of substrate solution on the production pattern as well as operational stability The pattern of formation of IMO was the same to the one of soluble TG. The concentrations of glucose and isomaltose produced by the packed-bed reactor were gradually decreased as the flow rates were increased regardless of the concentrations and kinds of maltose solution as substrate. Isomaltotriose showed the same tendency except 10% maltose solution. But the concentration of panose was increased and then decreased as the flow rates were increased. The maximum yield of IMO was 52.1% when 10% (w/v) solution was fed to the reactor at 2 mL./min feed rate. When each 20% and 30% (w/v) solution was respectively used at $0.5{\sim}1.0\;mL/min$, the maximum yield were $39.0{\sim}38.0%\;and\;12.1{\sim}14.2%$. The maximum yield was 36.3% at $0.5{\sim}1.0\;mL/min$ when a commercial maltose product containing 20% maltose was used. The reactor was stably operated at $55^{\circ}C$. 85% and 65% of initial activity was maintained for 144 hours and 288 hours of operation, respectively. A reactor analysis strongly an immobilized TG system could apply to continuous production of IMO.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.59-69
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• 2012

This study examines the role of mathematics anxiety as a mediator between self efficacy and mathematics skills using a series of regression analyses suggested by Baron RM & Kenny DA(1986). The participants include college students who enrolled in the Food Service Production and Operation course in a department of hotel and restaurant management at a college in the United States. Descriptive analysis, principal component analysis, reliability test, and a series of regression analyses were used for data analysis using SPSS 19.0. In order to collect data for the study, General Self Efficacy Scale(GSES) and Math Anxiety Rating Scale(MARS) were utilized, and they turned out to be reliable(${\alpha}$=.906 and ${\alpha}$=.890, respectively). A significant negative relationship was found between self efficacy and mathematics anxiety. In addition, it was found that self-efficacious students performed better mathematics skills than those who had lower level of self efficacy. However, the relationship was no longer significant when the concept of mathematics anxiety was added, which satisfies the condition of mediation.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.264-274
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• 2001

About the patients who visited the emergency department of a hospital, investigative study was performed to assess and to classify them with triage tool, and to estimate the characteristics of them. 210 patients older than 15 years were investigated. Among them 11 patients who had responded inappropriately were excluded and remaining 210 patients were chosen as study subjects. Investigation had been performed for 30 days from Jan. 10, 2001 to Feb. 9, 2001. The triage tool was designed through the modification of triage tools developed by Kim and Choi. The data were analyzed with the SPSS program using mean, standard deviation, frequency, percentage, ANOVA and Scheffe's test. The results were as follows: 1. Of the characteristics of the study subjects, mean age of patients were 55.76 years and 70-79 years group which included 41 patients(20.6%) were most numerous. 101 (51.8%) patients visited emergency room by 119 emergency service and 91(45.7%) patients walked with assistance. 127 patients were cared in internal medicine department. 2. The distribution of triage scores were from minimum 6 points to maximum 18 points with mean $13.76{\pm}2.58$ points. 3. Triage scores had significant relationship with age(F=13.349,P=0.000), visiting method (F=8.832, P=0.000), walking status(F=28.185, p=0.000), care department(F=2.596, P=0.019), and preexisting disease(F=12.012, P=0.000). 4. After trage there were no urgent patient, 35 emergent patients(17.6%),109 subemergent patients(54.8%), and 55 nonemergent patients (27.6%). The result of emergency care were 80 admission(40.2%), 59 discharge (29.6%), 34 ICU admission(17.1%), 14 transfer to other hospital(7%), 10 operation (5%), and 2 death (2%). 5. About the time required for triage, mean duration to triage were $7.54{\pm}2.28$ mins in emergent patients, mean $7.23{\pm}2.50$ mins in subemergent patients and mean $6.49{\pm}2.19$ mins in nonemergent patients. There were no differences in duration to triage according to the severity of triage. 6. Time required in emergency treatment were mean $116.23{\pm}88.10$ in emergent patients mean $101.61{\pm}73.27$ in subemergent patients and mean $81.56{\pm}61.01$ in nonemergent patients. There were no significant difference among groups. This study depicted that triage scores were below the middle level and there were many geriatric patients in this hospital. Among the characteristics of patients, age, visiting method, walking status, care department, and accompanying disease could be data for triage of emergency patients. With triage score of a patient, the outcome of emergency care of a patient could be anticipated and this could be basal data in determining the priority of emergency nursing.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.791-794
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• 2010

This study presents channel design of a CDI stack to achieve high removal efficiency in a large scale by applying parallel flow structure with a concentrated stream. The flow pattern in the stack was simulated by COMSOL Multiphysics program. To prove the salt removal performance, a unit cell and 20 cell stacks were tested at a flow rate condition of 18 ml/min and 360 ml/min, respectively. The removal efficiencies of the unit cell and the 20 cell stacks were obtained as 70.8 % and 75.6 %, respectively, with 100 mg/L sodium chloride solution. During the operation of cell test, water pressures of unit cell and 20 cell pair stack maintained in the ranges of 1.1 psi and 1.3~1.5 psi, respectively. It was demonstrated that the parallel cell structure with two concentrated streams can be employed in a large scale CDI for salt removal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.625-633
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• 2020

this study, an expert AHP questionnaire analysis of public and private groups was conducted to take into consideration the requirements for realistic disaster services. Considered are public areas that manage disasters like fires and earthquakes that can be a major threat to national safety, as well as private areas that mainly develop disaster-related technologies. In the questionnaire, the public respondents valued accurate disaster situation information (ranked 4th and 6th) for citizens (1st), managers (3rd), and related organizations (2nd); the private sector highly valued the importance of three-dimensional (3D) control (ranked 1st, 3rd, and 5th) using future technologies. This study suggests the realization of a disaster-response service that meets the needs of public safety and technological innovation based on a 3D safety state information platform. We anticipate that this study will provide useful data for applying technology and for establishing detailed scenarios during the test bed and commercialization phases. We also expect that further studies will be conducted, such as the practical application and operation of realistic disaster response services, on the financial resources for the proliferation of local governments, and on policy support measures.

• Journal of the Korean Electrochemical Society
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• v.23 no.3
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• pp.57-65
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• 2020

It is crucial to investigate the thermal degradation of lithium-ion batteries (LIBs) to understand the possible malfunction at high temperature. Herein, we investigated the effects of surface film formation on the thermal degradation of lithium cobalt oxide (LiCoO₂, LCO) cathode that is one of representative cathode materials. Cycling test at 60℃ exhibited poorer cycleability compared with the cycling at 25℃. Cathodes after the initial 5 cycles at 60℃ (60-LCO) exhibited higher impedance compared to the cathode after initial 5 cycles at 25℃ (25-LCO), resulting in the lower rate capability upon subsequent cycling at 25℃, although the capacity values were similar at the lowest C-rate of 0.1C. In order to understand degradation of the LCO cathode at the high temperature, we analyzed the cathodes surface using X-ray photoelectron spectroscopy (XPS). Among various peaks, intensity of lithium hydroxide (LiOH) increased substantially after the operation at 60℃, and the C-C signal that represents the conductive agent was distinctly lower on 60-LCO compared to 25-LCO. These results pointed to an excessive formation of cathode-electrolyte interphase including LiOH at 60℃, leading to the increase in the resistance and the resultant degradation in the electrochemical performances.