• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.5
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• pp.581-589
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• 2021

With the recent increase in the introduction of micro-electric vehicles in Korea, interest in micro-electric vehicle user satisfaction is increasing to revitalize related markets. In this paper, a basic study was conducted on the development of public services using micro-electric vehicle based on the constituent factors of user satisfaction. The survey includes: ① 'Analytic Hierarchy Process (AHP) for selecting the priority factors of user satisfaction of micro-electric vehicles', ② 'A survey of micro-electric vehicles image' to collect data in advance for providing users' preferences and transportation services for micro-electric vehicles, ③ In order to investigate the user satisfaction level of users who actually operated micro-electric vehicles, the order of 'user satisfaction survey of micro-electric vehicle drivers' was conducted. In the Analytic Hierarchy Process (AHP) analysis, it was found that users regarded as important in the order of 'user utilization data', 'vehicle movement data', and 'charging service data'. In the micro-electric vehicle image survey, users perceived micro-electric vehicles more positively in terms of "safety", 'durability', 'Ride comfort', 'design', 'MOOE (Maintenance and other operating expense)', and 'environment-friendly' when comparing micro-electric vehicles with electric motorcycles. In the survey on the user satisfaction of micro-electric vehicle drivers, the use of micro-electric vehicle did not directly affect work performance efficiency, and there was an experience of being disadvantaged on the road due to the size of the micro-electric vehicle, and driving in a cluster of micro-electric vehicle for outdoor advertisements. The city's public relations effect was great, but it was concerned about safety. In the future, based on the results of this study, we plan to build a user satisfaction structural equation model, preemptively discover feedback R&D for micro-electric vehicle utilization services in the public field, and actively seek to discover new public mobility support services.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.86-92
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• 2022

Recently, the bio-healthcare market is enlarging worldwide due to various reasons such as the COVID-19 pandemic. Among them, biometric measurement and analysis technology are expected to bring about future technological innovation and socio-economic ripple effect. Existing systems require a large-capacity battery to drive signal processing, wireless transmission part, and an operating system in the process. However, due to the limitation of the battery capacity, it causes a spatio-temporal limitation on the use of the device. This limitation can act as a cause for the disconnection of data required for the user's health care monitoring, so it is one of the major obstacles of the health care device. In this study, we report the concept of a standalone healthcare monitoring module, which is based on both triboelectric effects and electromagnetic effects, by converting biomechanical energy into suitable electric energy. The proposed system can be operated independently without an external power source. In particular, the wireless foot pressure measurement monitoring system, which is rationally designed triboelectric sensor (TES), can recognize the user's walking habits through foot pressure measurement. By applying the triboelectric effects to the contact-separation behavior that occurs during walking, an effective foot pressure sensor was made, the performance of the sensor was verified through an electrical output signal according to the pressure, and its dynamic behavior is measured through a signal processing circuit using a capacitor. In addition, the biomechanical energy dissipated during walking is harvested as electrical energy by using the electromagnetic induction effect to be used as a power source for wireless transmission and signal processing. Therefore, the proposed system has a great potential to reduce the inconvenience of charging caused by limited battery capacity and to overcome the problem of data disconnection.

• Journal of Korea Entertainment Industry Association
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• v.14 no.4
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• pp.321-331
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• 2020

This study was conducted to investigate communication competence, clinical competence and experience of handover which influence self-efficacy of handover among nursing students. The study design was a descriptive survey. A total of 255 students were recruited from nursing departments in G-city. Structured questionnaire was self-administrated from June to September, 2019. The collected data were analyzed using t-test, ANOVA, Pearson's coefficient and stepwise multiple regression. As results of the study, communication competence 57.3, clinical competence 69.8 and self-efficacy of handover was 33.8. Self-efficacy of handover had significant differences in gender(F=4.60, p<.001), age(F=16.72, p<.001), grade(t=-6.39, p<.001), satisfaction of clinical practice(F=3.68, p=.027), education experience about handover(t=26.44, p<.001), experience of handover(t=4.84, p<.001), fear of handover(F=16.97, p<.001), and handover importance of patient's safety(F=6.42, p=.002). Self-efficacy of handover had significant positive correlations with communication competence(r=.249, p<.001) and clinical competence(r=.426, p<.001). In multiple regression analysis, fear of handover(β=-.294, p<.001), clinical competence(β=.252, p<.001), grade(β=.191, p=.001), experience of handover(β=.185, p<.001), gender(β=.150, p=.003), and education experience about handover(β=.126, p=.017) were significant factors of self-efficacy of handover explaining 40.0%(F=29.26, p<.001) of the variables. In conclusion, to enhance self-efficacy of handover for nursing students, it is necessary to develop educational program for increasing experiences of handover, education experience about handover, and clinical competence.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.1
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• pp.58-72
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• 2009

In this study, the organic matter and biomass was characterized by using respirometry based on ASM No.2d (Activated Sludge Model No.2d). The activated sludge models are based on the ASM No.2d model, published by the IAWQ(International Association on Water Quality) task group on mathematical modeling for design and operation of biological wastewater treatment processes. For this study, OUR(Oxygen Uptake Rate) measurements were made on filtered as well as non-filtered wastewater. Also, GC-FID and LC analysis were applied for the estimation of VFAs(Volatile Fatty Acids) COD(S_A) in slowly bio-degradable soluble substrates of the ASM No.2d. Therefore, this study was intended to clearly identify slowly bio-degradable dissolved materials(S_S) and particulate materials(X_I). In addition, a method capable of determining the accurate time to measure non-biodegradable COD(S_I), by the change of transition graphs in the process of measuring microbial OUR, was presented in this study. Influent fractionation is a critical step in the model calibrations. From the results of respirometry on filtered wastewater, the fraction of fermentable and readily biodegradable organic matter(S_F), fermentation products(S_A), inert soluble matter(S_I), slowly biodegradable matter(X_S) and inert particular matter(X_I) was 33.2%, 14.1%, 6.9%, 34.7%, 5.8%, respectively. The active heterotrophic biomass fraction(X_H) was about 5.3%.

• Journal of the Korea Society of Computer and Information
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• v.16 no.2
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• pp.267-278
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• 2011

This study examines the relationship among stock options, pay equity, organizational commitment. Employees who received stock options tend to perceive their pay more equitable and the tendency shows a positive relationship among the amount of stock options and the equity perception. Also employees who received stock options perceive greater procedural equity, as they recognize stock options are awarded to many employees. However, the perception of stock options was not significantly associated with organizational commitment, turnover intention, and pay satisfaction. In 2003, the study surveyed 115 employees who received stock options in 10 publicly owned Korean firms that introduced stock option plans. The statistical analysis leads to the conclusions as follows. First, as the number of stock options increases, the receiver tends to perceive that pay system is more distributively equitable. Second, as the number of stock option receivers increases, the employees perceive the pay system more procedurally equitable. Third, stock option payments don't ensure that it improves pay satisfaction, turnover intention, and organizational commitment. This study shows a positive relationship that stock options work favorably in terms of pay equity, but the effect doesn't seem to be widely positive. The reason is that the introduction of stock options in domestic firms has been made only recently after the foreign exchange crisis in the late 1990s. More experiments and design issues should be discussed for the future.

• Food Science and Preservation
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• v.24 no.7
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• pp.957-964
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• 2017

The purpose of this study was to determine the optimum spray drying conditions of soft persimmon latte using response surface methodology that is a statistical procedure used for optimization studies. A central composite design was applied to investigate the effects of independent variables, inlet temperature ($X_1$), air flow rate ($X_2$), and feed flow rate ($X_3$), on responses such as yield, water absorption index, and total phenolic compounds. Statistical analysis revealed that independent variables significantly affected all the responses. A maximum yield of 8.11 g was obtained at $90^{\circ}C$ of $X_1$, 51.82 mL/min of $X_2$ and 7.00 mL/min of $X_3$. A minimum water absorption index of 0.58 was obtained at $101^{\circ}C$ of $X_1$, 60.00 mL/min of $X_2$ and 17.00 mL/min of $X_3$. A maximum total phenolic compounds of $298.02{\mu}g/mL$ was obtained at $90^{\circ}C$ of $X_1$, 43.33 mL/min of $X_2$ and 17.00 mL/min of $X_3$. In conclusion, the best spray drying conditions were as follows: $X_1$, $90^{\circ}C$; $X_2$, 53 mL/min; $X_3$, 17 mL/min. Under those optimal conditions, the powder's yield (7.46 g), water absorption index (0.54), and the content of total phenolic compounds ($294.75{\mu}g/mL$) were estimated.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.13-25
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• 2016

This study aims to analyze the change process in order to set the improvement strategies for the zoo in the Seoul Children's Grand Park. The zoo can be reviewed through three significant time periods with noticeable changes. As a framework to analyze the major changes that happened in the zoo, this study looks at the changes in terms of the planning aspect as well as the animal welfare and program operation aspect. The findings are as follows: first, the era of general theme park turned out to have focused on exhibiting animals to meet visitor demands by expanding the zoo area of the zoo without enlarging stockyards for the animals. Second, the environmental park era created a zoo having entertaining and educational functions by arranging animal houses with the concept of zoological taxonomy and introducing animal behavioral enrichment, animal welfare programs and visitor participatory programs. The era of the zoo as an Urban Cultural Park improved old animal houses and facilities for the welfare of the animals and increased educational programs to preserve species and provide environmental education. The current status of the zoo turns out not to meet the conditions for creating an ecological zoo, which is the overall goal for contemporary zoos. The improvement strategies based on the analysis through three different eras are three-fold. First, the zoo needs to improve the boundary conditions of the animals to showcase animal wildness through landscape immersion. Second, the zoo should provide a shared environment for animals from the same habitats by changing the classification methods from the existing polyphyletic taxon to a classification that considers ecological habitat. Third, the zoo needs to develop various ecological education programs by supplementing specialists in professional education.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.169-174
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• 2008

Statement of problem: Changes of the marginal bone around dental implants have significance not only for the functional maintenance but also for the esthetic success of the implant. It was proposed that bone-retention elements such as microthreads at the coronal part of implant might help maintain the marginal bone level. Purpose: This study was designed to evaluate the effect of microthread configuration within the marginal coronal portion of the implant fixture at the marginal bone changes after loading around two different external hex implants. Material and methods: Twenty-four patients were included and randomly assigned to treatment with $Br{{\aa}}nemark$ system implants (Group 1, rough-surfaced implants, n=20) and Oneplant system implants (Group 2, rough-surfaced neck with microthreads, n=20). Clinical and radiographic examinations were conducted at baseline (implant loading) and 1 year postloading. Data analysis was performed by the SAS statistical package version 9.1.3 (SAS Institute, Cary, NC, USA) and the final model was calculated by the MIXED procedure (three-level ANCOVA) for marginal bone change of each test group at baseline and 1 year follow-up. Results: Comparing to baseline, significant differences were noted in marginal bone level changes for the 2 groups at 1 year follow-up (P<0.05). Group 1 had a mean crestal bone level changes of $0.83{\pm}0.31mm$; Group 2 had a mean crestal bone level changes of $0.44{\pm}0.36mm$. Rough-surfaced with microthreads implants showed significantly less marginal bone loss than rough surfaced neck without microthread implants. Conclusion: A rough surface with microthreads at the implant was beneficial design to maintain the marginal bone level against functional loading.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.52-64
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• 2015

This research traced the characteristics of the semantic landscape, construction intent, landscape composition, and geomantic conditions of the area subject to the research based on the research methods of 'field investigation, document studies, and interviews,' centering around the entire area of Gokseong Hamheo-pavilion (Jeonnam Tangible Cultural Assets No. 160). The result of the research, specifically revealing the forms and methods by which the reciprocal view of nature and landscape composition appearing in the landscape of the entire area of Hamheo-pavilion, as part of the analysis and interpretation over the view-based construction characteristics and position of the entire area of Gokseong Hamheo-pavilion, can be summarized as follows. First, Hamheo-pavilion is a pavilion built as a resting area and as a venue for educational activities in 1543 in the nearby areas after Gwang-hyeon Sim founded Gunjichon-jeongsa for educational activities and dwelling purposes at Gunchon at the 30th year of King Jungjong. Gunchon, where Hamheo-pavilion and Gunjichon-jeongsa is located, exhibits the typical form having water in the front, facing Sunja-river(present Seomjin-river), and a mountain in the back side. Dongak-mountain, which is a guardian mountain, is in a snail-type form where cows leisurely ruminate and lie on the riverside, and the Hamheo-pavilion area is said to be an area bordering on one's way of enjoying peace and richness as it is a place with plentiful grass bushes available for cows to ruminate and lie down while sheppards may leisurely play their flutes at the riverside. The back hill of Hamheo-pavilion is a blood vessel that enters the water into the underwater palace of the turtle, and the building sitting on the turtle's back is Hamheo-pavilion, and the Guam-jodae(龜巖釣臺) and lava on the southern side below the cliff can be interpreted to be the underwater fairly land wanted by the turtle.6) Second, Hamheo-pavilion is the scenery viewpoint of Sungang-Cheongpung (3rd Scenery) and Seolsan-Nakjo(雪山落照, 9th Scenery) among the eight sceneries of Gokseong, while also the scenery viewpoint of Hamheo-Sunja(2nd Scenery) and Cheonma-Gwiam(天馬歸岩, 3rd Scenery) among the eight sceneries of Ipmyeon. On the other hand, the pavilion is reproduced through the aesthetics of bends through sensible penetration and transcendental landscape viewed based on the Confucian-topos and ethics as the four bends among the five bends of Sunja-river arranged in the 'Santaegeuk(山太極) and Sutaeguek(水太極, formation of the yin-yang symbol by the mountain and water)' form, which is alike the connection of yin and yang. In particular, when based on the description over Mujinjeong (3rd Bend), Hoyeonjeong(4th Bend), andHapgangjeong(2nd Bend) among the five bends of Sunja-river in the records of Bibyeonsainbangan-jido(duringthe 18th century) and Okgwahyeonji(1788), the scenery of the five bends of Sunja-river allow to glimpse into its reputation as an attraction-type connected scenery in the latter period of the Joseon era, instead of only being perceived of its place identity embracing the fairyland world by crossing in and out of the world of this world and nirvana. Third, Hamheo-pavilion, which exhibits exquisite aesthetics of vacancy, is where the 'forest landscape composed of old big trees such as oak trees, oriental oak trees, and pine trees,' 'rock landscape such as Guam-jodae, lava, and layered rocks' and 'cultural landscape of Gunchon village' is spread close by. In the middle, it has a mountain scenery composed of Sunja-river, Masan-peak, and Gori-peak, and it is a place where the scenery by Gori-peak, Masan-peak, Mudeung-mountain, and Seol-mountain is spread and open in $180^{\circ}$ from the east to west. Mangseo-jae, the sarangchae (men's room)of Gunjichon-jeongsa, means a 'house observing Seoseok-mountain,' which has realized the diverse view-oriented intent, such as by allowing to look up Seol-mountain or Mudeung-mountain, which are back mountains behind the front mountain, through landscape configuration. Fourth, the private home, place for educational activities, pavilion, memorial room, and graveyard of Gunji-village, where the existence and ideal is connected, is a semantic connected scenery relating to the life cycle of the gentry linking 'formation - abundance - transcendence - regression.' In particular, based on the fact that the descriptions over reciprocal views of nature regarding an easy and comfortable life and appreciations for a picturesque scene of the areas nearby Sunja-river composes most of the poetic phrases relating to Hamheo-pavilion, it can be known that Hamheo-pavilion is expressed as the key to the idea of 'understanding how to be satisfied while maintaining one's positon with a comfortable mind' and 'returning to nature,' while also being expressed of its pedantic character as a place for reclusion for training one's mind and training others through metaphysical semantic scenery.

• Progress in Medical Physics
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• v.20 no.4
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• pp.277-289
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• 2009

Recently, functional MRI has been used to investigate the neurobiological mechanisms of acupuncture and the specificity of acupoint. The group data tend to be regarded as more important than the individual data in the most of previous studies. This study was designed to investigate the effect of the variability of individual data on the group results. A functional MRI (fMRI) of the whole brain was performed in fifteen healthy subjects during placebo and acupuncture stimulations at the ST36 acupoint. After remaining at rest for 30 seconds, the acupuncture was inserted and twisted at the rate of 2 Hz for 45 seconds and then the acupuncture was removed immediately. This process was repeated three times. Individual and group analyses were performed by voxel-based analyses using SPM2 software. Visual inspections of the activation and deactivation maps from individual sessions have shown the large variability across fifteen subjects. This means that the group data reflected the brain activation responses of only a few subjects. We suggest that the individual data should be presented to demonstrate the effect of acupuncture.