• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.113-117
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• 2001

Specific capacitance and charge-discharge rate of EDLC using activated carbon electrode were affected by the compositions of electrolytes, the conditions of charge-discharge and physical properties of activated carbon materials. The activated carbon electrode was prepared by dip coating method. Charge-discharge test and electrochemical experiments were carried out for various kinds of organic electrolytes. Effects of charge and discharge current density on the specific capacitance were studied. Characteristics of leakage current, self-discharge and time-voltage curves in optimum conditions of organic electrolytes were compared with conventional $1M-Et_4NBF_4/PC$ electrolyte. The EDLC using MSP-20(specific surface area: $2000m^2/g$) electrode and $1M-LiPF_6/PC-DEC(1:1)$ was exhibited th highest specific capacitance of 130F/g and low polarization resistances. The EDLC using MSP-20 electrode at $1M-LiPF_6/PC-DEC(1:1)$ was small leak current of 0.0004A for 15min, long voltage retention of 0.8V after 100h and linear time-voltage curves with small IR-drop.

• Journal of The Korean Society of Clinical Toxicology
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• v.20 no.2
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• pp.58-65
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• 2022

Purpose: Alcohol is one of the most commonly co-ingested agents in deliberate self-poisoning (DSP) cases presenting at the emergency department (ED). The increased impulsivity, aggressiveness, and disinhibition caused by alcohol ingestion may have different clinical features and outcomes in cases of DSP. This study investigates whether alcohol co-ingestion affects the clinical features and outcomes of DSP patients in the ED. Methods: This was a single-center retrospective study. We investigated DSP cases who visited our ED from January 2010 to December 2016. Patients were classified into two groups: with (ALC+) or without (ALC-) alcohol co-ingestion. The clinical features of DSP were compared by considering the co-ingestion of alcohol, and the factors related to discharge against medical advice (AMA) of DSP were analyzed. Results: A total of 689 patients were included in the study, with 272 (39.5%) in the ALC+ group. Majority of the ALC+ group patients were middle-aged males (45-54 years old) and arrived at the ED at night. The rate of discharge AMA from ED was significantly higher in the ALC+ group (130; 47.8%) compared to the ALC- group (p=0.001). No significant differences were obtained in the poisoning severity scores between the two groups (p=0.223). Multivariate analysis revealed that alcohol co-ingestion (odds ratio [OR]=1.42; 95% confidence interval [CI], 1.01-1.98), alert mental status (OR=1.65; 95% CI, 1.17-2.32), past psychiatric history (OR=0.04; 95% CI, 0.01-0.28), age >65 years (OR=0.42; 95% CI, 0.23-0.78), and time from event to ED arrival >6 hrs (OR=0.57; 95% CI, 0.37-0.88) were independent predictive factors of discharge AMA (p=0.043, p=0.004, p=0.001, p=0.006, and p=0.010, respectively). Conclusion: Our results determined a high association between alcohol co-ingestion and the outcome of discharge AMA in DSP patients. Emergency physicians should, therefore, be aware that DSP patients who have co-ingested alcohol may be uncooperative and at high risk of discharge AMA.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04a
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• pp.159-161
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• 2000

After the square type reset pulse, the condition of remaining wall charge has been experimentally investigated in AC-PDP with VDS (Versatile Driving Simulator) system, in which arbitrary driving waveform and sequence can be used. After the self-discharge process, almost wall charges are eliminated. But some wall charges are not and its quantity is dependent on the voltage of the reset pulse. When the voltage of the reset pulse is growing, its quantity is decreased. But if the voltage of the reset pulse is above 300V, the wall voltage due to remaining wall charge is constant and its value is found out 6V. Also it is found that its polarity is always same with the one made by the reset pulse. It means that the polarity is not changed by the self-discharge.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.526-526
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• 2012

DC magnetron discharges were studied using three-dimensional self-consistent particle-in-cell and Monte Carlo collisional (PIC-MCC) simulation codes. Two rectangular sputter sources (120 mm * 250 mm and 380 mm * 200 mm target sizes) were used in the simulation modeling. The number of incident ions to the Cu target as a function of position and simulation time was obtained. The target erosion profile was calculated by using the incident ions and the sputtering yields of the Cu target calculated with SRIM codes. The maximum ion density of the ion density distribution in the discharge was about $10^{10}cm^{-3}$ due to the calculation speed limit. The result may be less than one or two order of magnitude smaller than the real maximum ion density. However, the target erosion profiles of the two sputter sources were in good agreement with the measured target erosion profiles except for the erosion profile near the target surface, in which which the measured erosion width was broader than the simulation erosion width.

• Journal of the Korean housing association
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• v.11 no.1
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• pp.57-68
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• 2000

This study has been performed to review critical issues affecting continuous residence in profit(self-paid) assistant living facilities for the elderly in the United States. There are three factors influencing continuous residence of frail elderly in the facilities as long as they want without involuntary discharge : Financial ability, behavioral aspects, and facility management situation. Regarding financial ability, income, purchase of insurance policy, cashable assets, willingfulness to pay, and health status were found to be crucial determinants of continuous residence. Overall, 40-50% of those aged 65+ are financially able to stay in the assistant facilities as long as they want, without involuntary discharge. As for behavioral aspects, extroversions, congeniality, culture & life style, conscientiousness, preference for person, and physiological habits were found to be crucial determinants of continuous residence. As for the management situation, it is essential that facilities reach nature level of self-governing rights of the older residents and good local images, and conflicts among the residents and managing parties be resolved on the agreeable standards of inspectors. finally in this study, it is proposed that in Korea, national pension authority offer a liability package for assistant residence, for the case of individual bankruptcy.

• Journal of Electrochemical Science and Technology
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• v.9 no.1
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• pp.20-27
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• 2018

We describe a redox-enhanced electric double-layer capacitor (EDLC) that turns the electrolyte in a conventional EDLC into an integral, active component for charge storage-charge is stored both through faradaic reactions with soluble redox-active molecules in the electrolyte, and through the double-layer capacitance in a porous carbon electrode. The mixed-redox electrolyte, composed of vanadium and iodides, was employed to achieve high power density. The electrochemical reaction in a supercapacitor with vanadium and iodide was studied to estimate the charge capacity and energy density of the redox supercapacitor. A redox supercapacitor with a mixed electrolyte composed of 0.75 M NaI and 0.5 M $VOSO_4$ was fabricated and studied. When charged to a potential of 1 V, faradaic charging processes were observed, in addition to the capacitive processes that increased the energy storage capabilities of the supercapacitor. The redox supercapacitor achieved a specific capacity of 13.44 mAh/g and an energy density of 3.81 Wh/kg in a simple Swagelok cell. A control EDLC with 1 M $H_2SO_4$ yielded 7.43 mAh/g and 2.85 Wh/kg. However, the relatively fast self-discharge in the redox-EDLC may be due to the shuttling of the redox couple between the polarized carbon electrodes.

• Korean Journal of Adult Nursing
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• v.19 no.1
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• pp.132-143
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• 2007

Purpose: The purpose of this study was to identify effects of a self-management program on symptom and functional status, health perception, and quality of life(QOL) of patients with CHF. Methods: Patients with CHF as defined through clinical judgment using the Framingham criteria and EF<50% were enrolled in the study (experimental: 21, control: 20). The symptom focused self-management program consisted of coping behaviors for symptoms including dyspnea, chest discomfort/pain, dizziness, ankle edema, and basic self-management including medications, diets, activity, lifestyle changes. Experimental group received an educational booklet after survey, and periodic telephone follow-up by a trained nurse. Data were collected the 3rd day after admission and at 1 month, 3 months, and 6 months after discharge using questionnaires. Results: Significant differences were found in the presence of symptoms, health perception, and QOL between groups during follow-up. Although no significant difference was found in functional status, the experimental group reported better functional status than the control group. Conclusion: By facilitating self-management of CHF using tailored interventions including education programs and telephone monitoring, it is expected that patients will be able to monitor their symptoms routinely, adhere to therapeutic regimen, and have a better QOL.

• Child Health Nursing Research
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• v.12 no.2
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• pp.189-195
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• 2006

Purpose: The purpose of this study was to examine the effect of a maternal self-efficacy promotion program for Korean primiparas on maternal confidence and mother-infant interaction. Method: This study was non-equivalent quasi-experimental research with a control group selected by purposive sampling. Based on Bandura’s (1986) self-efficacy theory, the research team developed the maternal self-efficacy promotion program. The program included achievement experiences, verbal persuasion, and vicarious experiences. The program was provided through face-to-face teaching at the time of discharge, counseling sessions over the telephone, and a home visit. Subjects also learned about parenting skills using a videotape developed by the research team. Sixteen primiparas were recruited to the experimental group at one hospital in Kyongi province, and fifteen primiparas who were matched according to socioeconomic status were recruited to the control group at a postpartum care center in the same province. Results: Subjects in the experimental group demonstrated significantly higher maternal confidence and mother-infant interaction than those in the control group. Conclusion: The maternal self-efficacy promotion program appears to be an effective nursing intervention for parenting of first-time mothers in Korea.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.33 no.3
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• pp.59-66
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• 2022

Objectives: This study aimed to investigate the clinical characteristics of adolescents hospitalized through the emergency room for intentional self-harm or suicide attempts. Methods: This retrospective study used data from the Korean National Hospital Discharge In-depth Injury Survey conducted between 2006 and 2018 for individuals aged 10-24 years. The clinical characteristics of the patients were analyzed and compared across sex and age groups using the Rao-Scott chi-square tests and multiple logistic regression analysis for complex survey data. Results: The most common psychiatric diagnosis was mood disorder (22.0%), and more female patients were diagnosed with it than male patients (p=0.010). The 19-24 years age group was diagnosed with mood disorder the most compared to other younger groups (p=0.012). Male patients used lethal methods more than female patients (p=0.008), and the 19-24 years age group used more drug poisoning and cutting or piercing (p<0.001) for intentional self-harm or suicide attempts than younger groups. Conclusion: Adolescents hospitalized for intentional self-harm or suicide attempts showed significant differences in clinical characteristics across sex and age groups. These findings suggest that measures for preventing self-harm or suicide attempts need to be differentiated according to the sex and age of adolescents.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.179-190
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• 2011

The swirling flow developing in Francis turbine draft tube under part load operation leads to pressure fluctuations usually in the range of 0.2 to 0.4 times the runner rotational frequency resulting from the so-called vortex breakdown. For low cavitation number, the flow features a cavitation vortex rope animated with precession motion. Under given conditions, these pressure fluctuations may lead to undesirable pressure fluctuations in the entire hydraulic system and also produce active power oscillations. For the upper part load range, between 0.7 and 0.85 times the best efficiency discharge, pressure fluctuations may appear in a higher frequency range of 2 to 4 times the runner rotational speed and feature modulations with vortex rope precession. It has been pointed out that for this particular operating point, the vortex rope features elliptical cross section and is animated of a self-rotation. This paper presents an experimental investigation focusing on this peculiar phenomenon, defined as the upper part load vortex rope. The experimental investigation is carried out on a high specific speed Francis turbine scale model installed on a test rig of the EPFL Laboratory for Hydraulic Machines. The selected operating point corresponds to a discharge of 0.83 times the best efficiency discharge. Observations of the cavitation vortex carried out with high speed camera have been recorded and synchronized with pressure fluctuations measurements at the draft tube cone. First, the vortex rope self rotation frequency is evidenced and the related frequency is deduced. Then, the influence of the sigma cavitation number on vortex rope shape and pressure fluctuations is presented. The waterfall diagram of the pressure fluctuations evidences resonance effects with the hydraulic circuit. The influence of outlet bubble cavitation and air injection is also investigated for low cavitation number. The time evolution of the vortex rope volume is compared with pressure fluctuations time evolution using image processing. Finally, the influence of the Froude number on the vortex rope shape and the associated pressure fluctuations is analyzed by varying the rotational speed.