• Applied Chemistry for Engineering
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• v.33 no.6
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• pp.636-645
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• 2022

In this study, we investigated the adsorption characteristics of methyl orange (MO), an anionic dye, on ginkgo shell-based activated carbon (AC). For this purpose, ACs (GS-1, GS-2, and GS-4) with different textural properties were prepared using ginkgo shells and potassium hydroxide (KOH), a representative chemical activating agent. The correlation between the textural characteristics of AC prepared and the mixing ratio of KOH was investigated using nitrogen adsorption/desorption isotherms. The MO adsorption equilibrium experiment on the prepared ACs was conducted under different pH (pH 3~11) and temperature (298~318 K) conditions, and the results were investigated by Langmuir, Freundlich, Sips and temperature-dependent Sips equations. The feasibility of the MO adsorption treatment process of the prepared AC was also investigated using the dimensionless Langmuir separation factor. The heterogeneous adsorption properties of MO for the prepared AC examined using the adsorption energy distribution function (AED) were closely related to the system temperature and textural characteristics of AC. The kinetic results of the batch adsorption performed at different temperatures can be satisfactorily explained by the homogeneous surface diffusion model (HSDM), which takes into account the external mass transfer, intraparticle diffusion, and active site adsorption. The relationship between the activation energy value obtained by the Arrhenius plot and the adsorption energy distribution function value was also investigated. In addition, the adsorption process mechanism of MO on the prepared AC was evaluated using Biot number.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.6
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• pp.121-127
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• 2022

Smart mirror is an IoT device that attaches a display and an embedded computer to the mirror and provides various information to the useer along with the mirror function. This paper went beyond the form of dealing with smart mirrors only stand alone device the provide information to users, and constructed a network in which smart mirrors are connected, and proposed and implemented a CoMirror system that allows users to talk and share information with other smart mirror users. The CoMirror system has a structure in which several CoMirror clients are connected on one CoMirror server. The CoMirror client consists of Raspberry Pi, a mirror film, a touch pad, a display device, an web camera, etc. The server has functions such as face learning and recognition, user management, a relay role for exchanging messages between clients, and setting up for video call. Users can communicate with other CoMirror users via the server, such as text, image, and audio messages, as well as 1:1 video call.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.5
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• pp.607-616
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• 2022

Corrosion and degradation of reinforced structures due to abnormal climates and natural disasters further accelerate the aging of structures. Coping with the decrease in structure performance, many old structures are being repaired and reinforced with low-weight and high-strength materials such as glass fiber composite material (GFRP). To further contribute, this paper focus on a more economical and eco-friendly material, basalt fiber composite (BFRP), which provide a more effective lateral constraint effect for seismic reinforcement. The main variables considered in this study are the curing temperature during the manufacturing of BFRP and the material characteristics of the target concrete member. The lateral constraint reinforcement effect was investigated through the evaluation of the performance of normal concrete and those with improved durability through fiber reinforcement. The reinforcement effect was 3.15 times for normal concrete and 3.72 times for fiber reinforced concrete, and the difference in reinforcement effect due to the improvement of the durability characteristics of the compression member was not significant. Lastly, the performance of the BFRP was compared with the results of the GFRP reinforcement from the previous study. The effect of the BFRP reinforcement was 1.18 times better than that of the GFRP reinforcement.

• Journal of the Korean Applied Science and Technology
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• v.39 no.5
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• pp.605-613
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• 2022

The genus Flavobacterium, type genus of the family Flavobacteriaceae and a member of the phylum Bacteriodetes includes gram-negative and yellow-pigmented rods. Those bacteria have been isolated from various environments of the earth. A yellow-pigmented, gram-negative rod was isolated from a pond in the campus of the Changwon University, Changwon, Kyeongnam and designated as strain B1. Strain B1 was further analyzed physiologically, biochemically and phylogenetically, and concluded to be a member of genus Flavobacterium. BLAST search of the 16S rRNA gene sequence of strain B1 shows homology no higher than 99.0% with those sequences of other bacteria. The major fatty acids of strain B1 are iso-C_15:0 (19.6%), summed feature 3(C_16:1 ω7c and/or C_16:1 ω6c, 16.1%), iso-C_17:0 3OH(10.2%), iso-C_15:0 3OH(8.4%) and iso-C_15:1 G(6.6%) showing significant differences in fatty acid compositions between strain B1 and the other known Flavobacterium species. DNA sequence of 16S rRNA gene of strain B1 was deposited in genbank under accession number OP060681.

• Korean Journal of School Psychology
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• v.17 no.3
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• pp.287-306
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• 2020

The purpose of this study was to investigate the effect of motivation promotion on task performance. Unlike most previous studies that have used survey methods, this study examined the effects of motivation promotion on arithmetic and linguistic task performances under experimental conditions. Effort-inducing instructions and positive feedbacks were used to promote participants' motivation. Experiments 1 and 2 examined the effect of effort-inducing instructions and positive feedback on participants' autonomous selection of task difficulty when performing arithmetic and linguistic tasks. The results of the both experiments showed that the experimental group which received effort-inducing instructions and positive feedback chose more difficult task than the control group did. Experiment 3 examined whether motivation promotion enhances task performance and task persistence. The experimental group was more accurate and persistent than the control group. The results of the current study offer experimental evidence suggesting that activating intrinsic motivation through motivation promotion improves attitudes toward tasks and task performance.

• The Korean Society of Law and Medicine
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• v.22 no.2
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• pp.49-79
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• 2021

Due to defendant's wrongful act by implant surgery, plaintiff has been suffered serious damages to his face and teeth, and pain caused by establishing implanted teeth. Jeonju Appellate Court sentenced to pay future medical expenses and alimony to the plaintiff in compensation for breach of duty or torts. The ruling is designed to relieve the burden of proof because it is extremely difficult for non-experts to determine whether dentists violated their 'duty of care' or whether there was a causal relationship between damages to medial treatment. It was judged that if symptoms that contributed to the patient's significant outcome occurred during or after surgery, such symptoms could be presumed to have been caused by medical negligence if indirect facts were proven to be other than medical negligence. Originally, the shifting of burden of proof in Germany, has already been developed in medical malpractice case since 1940s. In order to guarantee the patients' right, §630h German Civil Code (BGB) - presumption of negligence in the realization of controllable risk- has been also legislated. BGH (Bundesgerichtshof) has been interested in ensuring that the principle of equality between patients and doctors. So, in this study, we wanted to refer to German precedent cases to analyzing Korean medical malpractice lawsuit. In particular, the decision could be significant in that it approaches closer to allows the shifting burden of proof in drastically growing dental malpractice cases. This is clearly confirmed in the judgment of the dentist's "fault" that "if indirect facts about the symptom or occurrence are proven to be cause other than medical negligence, such symptoms can be presumed to be due to medical negligence."

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.8-16
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• 2002

This study was performed to produce the high reactive lignin zero substrates from autohydrolyzed wood resources. In chemical compositions of used raw-materials, there were significant differences between two species, Japanese larch (Larix leptolepis) and oak (Quercus mongolica) woods. Japanese larch contained 25 to 3.5 times higher amounts of extractives than oak wood, which is mainly derived from high content of arabinogalactan in Japanese larch wood. Oak wood has 5% lower lignin content and 3% higher holocellulose and pentosans than larch wood. Concerned to changes in wood components during autohydrolysis pretreatment at 22 kg/cm² steaming pressure for 5~60 min, glucose content was constant during pretreatment, while hemicellulose and lignin were abruptly changed. Hemicellulose fraction was decreased significantly and lignin contents increased because of its condensation reaction with hemicellulose degradation products. The pH of hydrolyzates during pretreatment was decreased, reached upto pH 3 and since then leveled off. In the case of oak wood, same tendency was observed as in Japanese larch. Autohydrolysis followed by sodium chlorite and sulfite or bisulfite pretreatment was very effective in delignification of the substrates. In particular, two-stage delignification of autohydrolyzed woods with alkali and O₂-alkali resulted in very low lignin content substrates, such as 0~0.2% lignin substrate.

• Journal of Korean Medicine Rehabilitation
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• v.32 no.1
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• pp.51-62
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• 2022

Objectives Objective of this study is to investigate the role of paraspinal muscles by examining the correlation between slip percentage (SP) of spondylolisthesis and fatty infiltration of lumbar paraspinal muscle. Methods Retrospective analysis was performed on 45 patients diagnosed with spondylolisthesis based on medical records. Using T2-weighted axial magnetic resonance imaging, cross-sectional areas (CSAs) of psoas major (PM), multifidus (MU) and erector spinae (ES) were calculated and divided by CSA of lower level vertebral body (VB). SP was measured using sagittal T2-weighted images. Correlation of SP with muscle relative cross-sectional area (RCSA) and muscle fatty infiltration by Goutallier classification was respectively analyzed using Spearman correlation. Statistic assessment conducted by Wilcoxon signed rank test and paired t-test using program GraphPad prism 5 (GraphPad Software, Inc., San Diego, CA, USA). Results Spondylolisthesis forward slip percentage by Taillard's method was negatively associated with both side MU RCSAs. No significant correlation was found between PM RCSA, ES RCSA and SP. Forward slippage was significantly correlated with fatty infiltration of lumbar paraspinal muscle measured by Goutallier classification. Conclusions This study is to understand the role of paraspinal muscle affecting spinal instability by investigating correlation between statistical deviation of lumbar muscle characters (RCSA, fatty infiltration of lumbar muscle) and SP. We found that spondylolisthesis SP is positively related to fatty infiltration of lumbar paraspinal muscle. and is negatively associated with both side MU RCSAs.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.327-333
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• 2021

The two main hypotheses that explain why invasive alien plants successfully colonize new environments are: 1) invasive alien plants are functionally different from native plants in a community, and 2) the plants can adapt well to new environments because they are functionally similar to native plants. The present study investigated the functional traits of naturalized alien herbaceous plants and their native neighbors in a riparian park area near the Hapcheon-Changyeong weir along the Nakdong River to determine which of the two hypotheses applied to the study area. According to the results, leaf functional traits, such as leaf area, specific leaf area, leaf thickness, leaf dry matter content, leaf nitrogen content, and leaf carbon content differed between naturalized alien and native plants, which could be attributed to the higher leaf nitrogen contents in naturalized alien plants than in native plants. The high leaf nitrogen contents are associated with high photosynthetic rates, which lead to effective resource use and rapid growth; therefore, naturalized alien plants growing in the study area were considered to have such functional traits. The results of the present study support the hypothesis that the successful establishment of invasive alien plants is attributed to the functional trait differences between invasive and native plants.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.701-718
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• 2021

Geological field surveys and a series of laboratory tests were conducted to obtain data related to landslides in Sancheok-myeon, Chungju-si, Chungcheongbuk-do, South Korea where many landslides occurred in the summer of 2020. The magnitudes of various factors' influence on landslide occurrence were evaluated using logistic regression analysis and an artificial neural network. Undisturbed specimens were sampled according to landslide occurrence, and dynamic cone penetration testing measured the depth of the soil layer during geological field surveys. Laboratory tests were performed following the standards of ASTM International. To solve the problem of multicollinearity, the variation inflation factor was calculated for all factors related to landslides, and then nine factors (shear strength, lithology, saturated water content, specific gravity, hydraulic conductivity, USCS, slope angle, and elevation) were determined as influential factors for consideration by machine learning techniques. Minimum-maximum normalization compared factors directly with each other. Logistic regression analysis identified soil depth, slope angle, saturated water content, and shear strength as having the greatest influence (in that order) on the occurrence of landslides. Artificial neural network analysis ranked factors by greatest influence in the order of slope angle, soil depth, saturated water content, and shear strength. Arithmetically averaging the effectiveness of both analyses found slope angle, soil depth, saturated water content, and shear strength as the top four factors. The sum of their effectiveness was ~70%.