• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.199-207
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• 2022

Lithium-sulfur batteries (LSBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) owing to their high energy density and economic viability. In addition, all-solid-state LSBs, which use solid-state electrolytes, have been proposed to overcome the polysulfide shuttle effect while improving safety. However, the high interfacial resistance and poor ionic conductivity exhibited by the electrode and solid-state electrolytes, respectively, are significant challenges in the development of these LSBs. Herein, we apply a poly (ethylene oxide) (PEO)-based composite solid-state electrolyte with oxide Li₇La₃Zr₂O₁₂ (LLZO) solid-state electrolyte in an all-solid-state LSB to overcome these challenges. We use an electrochemical method to evaluate the degradation of the all-solid-state LSB in accordance with the carbon content and loading weight within the cathode. The all-solid-state LSB, with sulfur-carbon content in a ratio of 3:3, exhibited a high initial discharge capacity (1386 mAh g^-1), poor C-rate performance, and capacity retention of less than 50%. The all-solid-state LSB with a high loading weight exhibited a poor overall electrochemical performance. The factors influencing the electrochemical performance degradation were revealed through systematic analysis.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.488-500
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• 2022

Most fungal infections by opportunistic yeast pathogens such as Candida spp. are the major causes of morbidity and mortality in patients with lowered immune. Previous studies have reported that some strains of Candida secret secondary metabolites play an important role in the decreasing of immunity in the infected patient. In this study, 110 Candida spp. were isolated from different clinical specimens from Baghdad hospitals. Candida isolates were identified by conventional methods, they were processed for Candida speciation on CHROMagar. The results of identification were confirmed by internal transcribed spacer (ITS) sequencing. Phylogenetic trees were analyzed with reference strains deposited in GenBank. Antifungal susceptibility testing was evaluated by the disc diffusion method and performed as recommended by the Clinical and Laboratory Standard Institute (CLSI) M44-A document. Candida isolates investigated produce secondary metabolites gliotoxin with HPLC technique and quantification. Out of 110 Candida isolates, C. albicans (66.36%) was the most frequent isolate, followed by the isolates of C. tropicalis (10.9%) and C. glabrata (6.36%) respectively. Concerning the antifungal susceptibility test, Candida isolates showed a high level of susceptibility to Miconazole (70.9%), Itraconazole (68.2%), and Nystatine (64.5%). The ability of obtained isolates of Candida spp. to produce gliotoxin on RPMI medium was investigated, only 28 isolates had the ability to secret this toxin in culture filtrates. The highest concentrations were detected in C. albicans (1.048 ㎍/ml). Gliotoxin productivity of other Candida species was significantly lower. The retention time for gliotoxin was approximately 5.08 min.

• Membrane and Water Treatment
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• v.15 no.1
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• pp.21-29
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• 2024

1H,1H,2H,2H-perfluorodecytriethoxysilane (C₁₆H₁₉F₁₇O₃Si) be successfully applied to the hydrophobic modification of Al₂O₃ tubular ceramic membrane. Taking the concentration of modification solution, modification time, and modification temperature as factors, orthogonal experiments were designed to study the hydrophobicity of the composite membranes. The experiments showed that the modification time had the greatest impact on the experimental results, followed by the modification temperature, and the modification solution concentration had the smallest impact. Concentration of the modified solution 0.012 mol·L^-1, modification temperature 30 ℃ and modification time 24 h were considered optimal hydrophobic modification conditions. And the pure water flux reached 274.80 kg·m^-2·h^-1 at 0.1MPa before hydrophobic modification, whereas the modified membrane completely blocked liquid water permeation at pressures less than 0.1MPa. Air gap membrane distillation experiments were conducted for NaCl (2wt%) solution, and the maximum flux reached 4.20 kg·m^-2·h^-1, while the retention rate remained above 99.8%. Given the scarcity of freshwater resources in coastal areas, the article proposed a system for seawater desalination using air conditioning waste heat, and conducted preliminary research on its freshwater production performance using Aspen Plus. Finally, the proposed system achieved a freshwater production capacity of 0.61 kg·m^-2·h^-1.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.484-498
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• 2023

This study aimed to analyze the appropriateness of the criteria and methods of the feasibility study for national park re-planning. The rate of 'release area' was derived at a lower rate in the absolute evaluation (the second) than the relative evaluation(the third) Seoraksan and Juwangsan National Parks as well as Gayasan National Park. Despite the third evaluation method aiming to maintain park area through retention by setting the areas available for release as 10% rather than applying release, it was found that the absolute evaluation method did not derive more areas available for release. When the second and third ecology-based assessments were applied to study sites, both second and third ecological-based assessments showed that the actual release areas were not reflected in the extraction in 2011. Consequently, it was found that the ecological-based assessment was only a means of assistance instead of a means of critical decision-making for determining the release area. From the district adjustment of the park planning easibility study, it can be determined that interactive exchange and priority application of release criteria as external factors acted more significantly.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.4
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• pp.135-149
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• 2020

As youth employment has become a social issue every year, the government is pushing for policies to support youth start-ups to create jobs voluntarily as a way to enhance the youth employment rate. In the case of young people in Gangwon Province, the number of people moving to other regions is increasing. This research is intended to empirically analyze the actual achievements of youth start-ups through the 'Youth Start-up Project' in Gangwon-do. It was divided into four categories: participation in government support, education completion, intellectual property right retention, and certification retention, which are characteristics of start-up companies, and hypotheses that they will have a positive impact on start-up performance (sales amount, duration of existence, or whether they are retained or not). Age and geographical factors (Yeongdong and Yeongseo) were injected as control variables to see how they affect them. Furthermore, empirical analysis was conducted by setting up a hypothesis that the characteristics of start-up companies and subsequent support between start-up performance would have a positive intermediary effect. The research results showed that the remaining characteristics, except for education completion, had a positive impact on sales, and that the more participation in government projects, the longer the duration of the company's existence. In addition, the level of participation in government support projects was significant in the direction of the government. The analysis results of the parameter, follow-up support, had a positive impact on the start-up performance, and the subsequent support mediating effect showed the mediating effect of the start-up performance, except for geographical factors. The results of this study suggest the need for customized support suitable for the characteristics of youth start-ups in order to enhance the performance of young start-ups. Support agencies need to refer to corporate characteristics for smooth management and selection. In the Gangwon-do area, the government should seek to provide timely and organic support for start-up companies in order to produce successful start-up cases.

• Journal of the Korean Chemical Society
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• v.63 no.4
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• pp.246-252
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• 2019

In the system of GC-OTC/FID (Gas chromatography-Open Tubular Column/Flame Ionization Detector), DMSO (Dimethyl sulfide) solvent was used to separate the polar solvents (Alcohols). In this system DMSO was eluted later than the separated polar solvents. At this system to calculate chromatographic factors [adjusted retention time ($t_R^{\prime}=t_R-t_O$), capacity factor{$k^{\prime}=(t_R-t_O)/t_O$} and separation factor {${\alpha}=(t_{R2}-t_O)/(t_{R1}-t_O)$}], dead time($t_O$) is necessary, but the method to calculate it has not been reported yet. Therefore, we have tried to develop $t_O$. To calculate $t_O$, we conversed DMSO retention time (DMSO $t_R$) to logarithm ($f(x)={\log}\;t_{R(DMSO)}{\rightarrow}t_O$, $t_O={\log}$ 9.551=0.980). To confirm the optimization of the developed method, we compared with $CH_4\;t_R$ and ${\ln}\;t_{R(DMSO)}$. Both of the values calculated by $CH_4\;t_R$ and ${\ln}\;t_{R(DMSO)}$ were not suitable in the calculation k' and ${\alpha}$. The developed method in this study{${\log}\;t_{R(DMSO)}$} has satisfied both of the values k' criteria (1${\alpha}(1<{\alpha}<2)$. The developed calculation method in this study was easy and convenient, therefore it can be expected to be applied to these similar systems.

• Herbal Formula Science
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• v.16 no.1
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• pp.15-27
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• 2008

This report describes 46 studies related to the use of Fructus Ponciri Seu Aurantii main blended prescriptions from Dongeuibogam. The following conclusions were reached through investigations on the prescriptions that use Fructus Ponciri Seu Aurantii as a key ingredient. 1. 19.6% of feces recorded the largest number of clinical frequency of the prescriptions in therapeutic use when Fructus Ponciri Seu Aurantii was taken as a monarch drug in prescriptions. In addition, 13.0% of each of a cough and an abdominal mass with distention and pain ranked second. 2. Prescriptions that utilize Fructus Ponciri Seu Aurantii as the main ingredient are used in the treatmeant of 5 diseases related to each of feces and an abdominal mass with distention and pain, and they are also used for treating different types of diseases related to the following ; a cough, a chest, ribs, eyes, the fullness in the chest, Qi, skin areas. 3. In the view of the causative agent of a disease, the prescriptions which are compounded with Fructus Ponciri Seu Aurantii as a monarch drug are related to endogenous agents such as seven emotion, food, deficiency, exogenous agents such as wind-cold pathogen, heat and non-endo-exopathogcnic factors like diseases due to external factors, poison. And in the view of the pathology of a disease, they are applied to the viscera pathology related to the lung, the spleen and stomach, the pathology of Qi and blood related to the reversed flow of Qi, the congestion of Qi, the deficiency of blood, the obstruction of Qi and blood, and the pathology about the retention of phlegm and fluid related to phlegm stagnation. 4. The dosage of Fructus Ponciri Seu Aurantii is 1.25pun(about 0,47g) to 2jeon(about 7.5g), however 1jeon(about 3.75g) has been taken the most for clinical application. 5. We can find out that according to herbs or prescriptions blended with itself, Fructus Ponciri Seu Aurantii makes a variety of functions to penetrate and remove stagnation, regulate Qi flow, relieve stagnation, expell wind and get rid of pain.

• Journal of Korean Academy of Nursing
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• v.30 no.4
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• pp.995-1005
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• 2000

This study was performed to identify the physiological and psychological variables related to successful weaning from a mechanical ventilator. The subjects of this study were 22 patients who received mechanical ventilation therapy for more than 3 days in intensive care units. Before the weaning trial, baseline data for following physiologic variables were obtained: spontaneous respiration rate, blood pressure, pulse rate, PaO2, PaCO2, PEEP, static compliance, minute ventilation, tidal volume, rapid shallow breathing index(f/VT), SaO2, PaO2/FiO2 and mean arterial pressure. During spontaneous breathing, physiologic and psychologic variables such as vital signs, ABG, perspiration, chest retraction, paradoxical respiration, dyspnea, anxiety, confidence and efficacy were measured. Successful weaning was defined as sustaining spontaneous respiration over 24 hours after extubation. Weaning failure was defined as the development of more than one of following signs: (1) hypoxemia, (2) CO2 retention or (3) perspiration, tachypnea, chest retraction, tachycardia, arrhythmia, hypotension or hypertension. Subjects (N=18) who successfully weaned from mechanical ventilator were compared with subjects (N=4) who failed. The results are as follows; Eighteen percents of the subjects failed during the weaning trial. Most subjects in the failed group were mechanically ventilated for long-time. This result shows that the success of weaning is more difficult in long-term ventilation patients. In the baseline data that was measured before weaning trial, the mean score of PaO2 in the successfully weaned group was 121mmHg. This is significantly higher than the mean score of PaO2 in the failed group(95mmHg). However, the scores of pH, tidal volume, f/VT, pulse rates, blood pressure, mean airway pressure, SaO2, and PaCO2 were similar between the two groups. Specially the scores of f/VT index as a predominant predictor for successful weaning were not significant (f/VT=44.4) and (f/VT=47). During spontaneous breathing, the scores of dyspnea and anxiety level in the successfully weaned group were less than those of the failed group. On the contrary, the scores of confidence and efficacy in the successful group were greater than those of the failed group. In conclusion, the baseline data that were measured before weaning trial were similar between the both groups, therefore future studies are needed to focus on searching other variables besides physiological parameters related to weaning outcome.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.6
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• pp.689-699
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• 2003

This study was to examine characteristics of treating toluene vapor, which gets to be problematic due to its harmful carcinogenicity and mass generation from various sources, through a biological treatment facility which is environment-friendly and adopts a high-efficient and low-cost clean technology. In order to identify whether Alnus Firma Fruit (AFF) can be used as a media for a bioreactor, its utility and basic operating factors, a study was conducted on pressure drop, supply of nutrient substances and retention time which are operating factors of a biofilter, and eliminating characteristics were compared between AFF and the conventional biological activatedcarbon (BAC) widely used as filter media. In the case of AFF, the initial microbial deposits was 2.3${\times}$10$^{7}$ CFU/g dry AFF, which represents the initial microbial density higher than the case of BAC showing 5.5${\times}$10$^{6}$ CFU/g dry BAC And it took about 2 weeks to acclimate until its eliminating rate got to be increased over 90%. As a result of comparing pressure loss taking place with the lapse of time between BAC and AFF, after 130 days passed at SV 25h$^{-1}$ , BAC showed that its eliminating efficiency had a tendency to drop greatly due to a great pressure loss (0.53\longrightarrow54.7 mm$H_2O$/m) caused by an excess of biomass as accumulated. On the other hand. AFF showed that the pressure drop was 0.53 mm$H_2O$/m, about 2 times as much as the initial pressure loss of 0.4 mm$H_2O$/m, which represents no great change in the pressure loss, and its eliminating efficiency was also shown to be continuously high. Therefore, when AFF was used as a filler for a biological treatment facility, a biological filter enabling improvement of the purifying efficiency to be promoted could be provided, and moreover, the pressure loss was so small that the filler replacement cycle or the back flushing cycle could be extended. So, even in terms of the operating cost, it was identified to be an economical filler When an inorganic material was used as a filler, the biofilters performance acted sensitively on whether nutrient substances were supplied or not. In the case of AFF with low adsorptivity, addition of ethyl-alcohol increased the solubility of toluene, and consequently, biodegradation got to be actively made by microbes, and thus, its eliminating rate could be increased. As the flow velocity and the inflow concentration got to be more increased, its eliminating rate got to be lower, and particularly, an increase in the flow velocity made its eliminating rate drop more greatly than an increase in the concentration.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.183-194
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• 2020

Recently, in Korea, financial institutions such as banks are most severely affected by the universalization of the Internet and smartphones. On the other hand, the use of online systems by financial institutions keeps increasing; the convenience of online services has a significant influence on the attraction and the retention of financial customers; consumer needs are also diversely expressed. This paper deduces from the precedent researches a mechanism that online financial system enhances the trust of customers -the medium of the online system and other customers- and its perceived easiness affects its perceived effectiveness and then all these internal variables induce satisfaction. Plus, this paper aims at verification of the hypothesis in terms of an extended technology acceptance model, based on the hypothesis that word of mouth and repurchase are significantly linked to this mechanism. Through this study, the researchers tried to check how the online service quality and emotional factors of financial institutions affect the users in accordance with the trend of changes in the service usage method of financial institutions, and confirmed that the hypothesis was not rejected.