• Geomechanics and Engineering
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• v.35 no.1
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• pp.29-39
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• 2023

As the intensity of urban underground space development increases, more and more tunnels are planned and constructed, and sometimes it is inevitable to encounter situations where tunnels have to underpass the river embankments. Most previous studies involved tunnels passing river embankments perpendicularly or with large intersection angle. In this study, a project case where two EPB shield tunnels with 8.82 m diameter run parallelly underneath a river embankment was reported. The parallel length is 380 m and tunnel were mainly buried in the moderate / slightly weathered clastic rock layer. The field monitoring result was presented and discussed. Three-dimensional back-analysis were then carried out to gain a better understanding the interaction mechanisms between shield tunnel and embankment and further to predict the ultimate settlement of embankment due to twin-tunnel excavation. Parametrical studies considering effect of tunnel face pressure, tail grouting pressure and volume loss were also conducted. The measured embankment settlement after the single tunnel excavation was 4.53 mm ~ 7.43 mm. Neither new crack on the pavement or cavity under the roadbed was observed. It is found that the more degree of weathering of the rock around the tunnel, the greater the embankment settlement and wider the settlement trough. Besides, the latter tunnel excavation might cause larger deformation than the former tunnel excavation if the mobilized plastic zone overlapped. With given geometry and stratigraphic condition in this study, the safety or serviceability of the river embankment would hardly be affected since the ultimate settlement of the embankment after the twin-tunnel excavation is within the allowable limit. Reasonable tunnel face pressure and tail grouting pressure can to some extent suppress the settlement of the embankment. The recommended tunnel face pressure and tail grouting pressure are 300 kPa and 550 kPa in this study, respectively. However, the volume loss plays the crucial role in the tunnel-embankment interaction. Controlling and compensating the tunneling induced volume loss is the most effective measure for river embankment protection. Additionally, reinforcing the embankment with cement mixing pile in advance is an alternative option in case the predicted settlement exceeds allowable limit.

• Korean Journal of Legislative Studies
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• v.25 no.2
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• pp.35-67
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• 2019

This study aims to analyze and evaluate the outcomes of the far-right parties in the 2019 European Parliament (hereinafter EP) elections. To this end, this study refrains from the conventional method of analyzing the number of seats of the political group(s) classified as far-right in the EP. Instead, the study takes a method based on the party family classification by summing up the number of the EP members who have been elected to the far-right party within individual member states. There are two reasons for the analysis of EP election results based on this far-right party family. Firstly, some of the far-right members of the EP do not join the political group(s) classified as far-right, and secondly, some of the political group(s) classified as far-right tends to be inhomogeneous. In this vein, this study attempts to analyze the outcomes of the far-right party in the 2019 EP elections based on the classification of the far-right party family. As a result, this study shows that the assessment of the European major press based on the number of seats of the political group(s) classified as far-right in the EP was inconsistent with the actual political landscape. According to the analysis of election results based on the classification of the far-right party family, the number of seats secured by the far-right parties in the 2019 EP elections corresponded to or significantly exceeded the results of previous polls. In addition, this is a significant increase in the seats of the far-right parties compared to the 2014 EP elections, and it is reasonable to affirm that the far-right parties have made great strides in the 2019 EP elections.

• Journal of Industrial Convergence
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• v.22 no.4
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• pp.31-38
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• 2024

The purpose of this study was to examine the current status of elderly sports both domestically and internationally, and to explore strategies for the activation of Silver Taekwondo as one of the sports disciplines for the elderly. To investigate the status of elderly sports globally, press releases and statistical data from various national public institutions and sports facilities (including the Ministry of Culture, Sports and Tourism, the Ministry of Health and Welfare, the Korean Statistical Information Service, e-National Indicators, and the Korea Sports Promotion Foundation) were collected. Comparative analysis with related papers, journals, and books led to the following findings for activating Silver Taekwondo. Firstly, elderly sports in South Korea are primarily conducted through welfare centers, with a preference for dance, yoga, and music, while martial arts, including Taekwondo, had a lower preference rate. To increase participation in Silver Taekwondo, a variety of marketing approaches, similar to those used internationally, such as experiential case studies in media, film production, distribution, and telephone promotions, are necessary. Secondly, the development of Silver Taekwondo programs tailored to the training targets and the cultivation of instructors capable of executing these programs are needed. The development of programs should involve collaboration with Taekwondo institutions, dojangs, universities, and lifelong education centers, requiring the participation of majoring students and elderly sports instructors.

• Advances in nano research
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• v.17 no.3
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• pp.213-219
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• 2024

Nanotechnology is one of the critical factors involved in enhancing the sensitivity of serum biomarker detection. To explore the relationship between serum APN, Cystatin C and MMP-9 levels in patients with hypertension during pregnancy and the severity and prognosis of the disease. A total of 75 cases of hypertensive disorder complicating pregnancy (HDCP) patients who were admitted to the hospital from February 5, 2023 to May 9, 2024, were selected as the study group, and 70 healthy pregnant women who were in the same gestational week were selected as the control group. The serum APN, MMP-9 and Cys C levels of pregnant women and HDCP patients with different disease severity were compared between the two groups, and the receiver characteristic curve (ROC) was used to analyze its diagnostic value. The serum APN, MMP-9 and Cys C levels of HDCP patients with different prognosis were compared, and the factors affecting the prognosis of patients were analyzed by Logistic regression. Nanoparticles could aslo enable the sensitive detection and quantification of APN, Cystatin C, and MMP-9 in serum samples, thus increasing the accuracy of the study. The serum MMP-9 and Cys C levels of pregnant women in the study group were significantly increased, and the APN level was significantly decreased (P<0.05). Serum MMP-9 and Cys C levels in patients with pregnancy-induced hypertension, mild preeclampsia, and severe preeclampsia gradually increased (r=0.768, 0.766; P<0.001), and APN levels gradually decreased (r=-0.748, P< 0.001). In the diagnosis of patients with HDCP, the sensitivity, specificity and AUC of APN single diagnosis were 70.00%, 82.67% and 9.848 respectively. The sensitivity, specificity and AUC of MMP-9 single diagnosis were 82.86%, 74.67% and 298.300 respectively. The sensitivity, specificity and AUC of Cys C single diagnosis were 80.00%, 74.67% and 1.301 respectively. There were significant differences in age, BMI, parity, dysthymia, disease severity, APN, MMP-9 and Cys between patients with poor prognosis of HDCP and patients with good prognosis of HDCP (P<0.001). The patient's age, BMI, disease severity, APN, MMP-9 and Cys Cwere all related to HDCP. They were related risk factors of HDCP (P<0.05).

• Journal of Korean Neurosurgical Society
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• v.29 no.11
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• pp.1421-1428
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• 2000

Objectives : The aim of this study is to evaluate the sequential metabolic changes in experimental hydrocephalus and the clinical applicability to the diagnosis and prognosis of hydrocephalus using proton MR spectroscopy. Methods : Hydrocephalus was experimentally induced in 30 cats(2-3kg body weight) by injecting 1ml of sterile kaolin suspension(250mg/ml) into the cisterna magna. Proton MRS was performed with a 1.5 T MRI/MRS unit (Vision Plus, Siemens) at pre-treatment and at 1, 3, 7, 14, 21, and 28 days after the kaolin injection. PRESS(TR/TE＝1500/270msec) technique was employed. The major metabolites which include N-acetyl aspartate (NAA), creatine(Cr), choline(Cho), and lactate(Lac) were quantitatively analyzed and the relative concentrations ratios were evaluated. Multislice $T_2$-weighted images were also obtained using fast spin echo sequence(TR/TE＝ 2500/96msec) to monitor the morphologic changes along with progression of hydrocephalus. Results : Hydrocephalus was successfully induced in all 30 cats. Twenty five cats died within 3 days and one at the end of the second week. In all animals, the NAA/Cr ratios initially decreased during the acute stage. In 4 surviving cats, the NAA/Cr ratios initially decreased during the acute stage(<14 days) and then gradually increased to the prekaolin level as follows : pre-kaolin($1.49{\pm}0.04$), day 1($1.11{\pm}0.07$), day 7($1.17{\pm}0.04$), day 14($1.40{\pm}0.03$), day 21 ($1.46{\pm}0.06$), day 28($1.43{\pm}0.03$). These levels were relatively well correlated with the symptomatologic improvement. Lactate peak, which reflects the evidence of ischemia, did not appear throughout the entire period except in one case which expired at the end of the second week. Conclusions : The NAA/Cr ratio of the sequential proton MRS in kaolin-induced hydrocephalic cats reflects a metabolic aspect of the hydrocephalus at each stage. A decreased NAA level at the early stage is from both neuronal and axonal damage which may provide diagnostic information in the acute stage of hydrocephalus. In addition, the initial fall of NAA/Cr ratio and recovery in the late stage, when no lactate peak emerges, may suggest that the main insult of the parenchyma is not to the neuron itself but to the axon, which may be related to a good prognosis. However, emergence of the lactate peak and unrecoverable NAA/Cr at the end of the acute phase may be a poor prognostic factor. In the chronic stage, recovery of NAA/Cr ratio may provide a diagnostic clue for the differentiation between hydrocephalus and cortical atrophy.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.323-332
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• 2010

Petroleum-based adhesive resins have extensively been used for the production of wood panels. However, it is necessary to develop environmentally friendly adhesive resins due to the increase of manufacturing cost and the environmental issue, such as the emission of volatile organic compounds, of the pertroleum-based adhesive resins. This study was conducted to formulate environmentally friendly adhesive resins using by rapeseed flour (RSF), which is the by-product of bio-diesel produced from rapeseed, for replacing petroleum-based adhesives with them. To formulate RSF-based adhesive resins, RSF was hydrolyzed in de-ionized water, 1% and 3% sodium hydroxide solutions. As a crosslinking agent, PF prepolymers were prepared with 1.8, 2.1 and 2.4 mol formaldehyde and 1 mol phenol (1.8-, 2.1- and 2.4-PF), and then mixed with RSF hydrolyzates to complete the formulation of RSF-based adhesive resins. The RSF-based adhesive resins were applied to fabricate 3-ply plywood panels. The solid content of RSF-based adhesive resins were ranged from 26.08% to 36.12% depending on the hydrolysis condition of RSF and PF prepolymer type with a high viscosity. The tensile shear strength and wood failure of plywood fabricated with RSF-based adhesive resins exceeded a minimum requirement of KS standard for ordinary plywood regardless of the hydrolysis condition of RSF and PF prepolymer type. Formaldehyde emissions of the plywood panels fabricated with 1.8-PF and RSF hydrolyzates were lower than that of E0 specified in the KS standard. Based on the results, RSF might be used as a raw material of environmentally friendly adhesives for the production of plywood panels, but further researches - the increase of solid content of RSF-based adhesives for reducing press time and the microscopic observation of plywood specimen for identifying the relationship between tensile shear strength and the penetration of adhesives into wood structure - are required to commercialize the RSF-based adhesives.

• Journal of the Korean Magnetics Society
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• v.18 no.3
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• pp.109-114
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• 2008

The samples were synthesized by using a solid state reaction. The X-ray diffraction pattern for $Ti_{0.96}Co_{0.02}Fe_{0.02}O_2$ showed a pure rutile phase with tetragonal structure, Mixtures of the proper proportions of the elements sealed in evacuated quartz ampoule were heated at $870{\sim}930^{\circ}C$ for one day and then slowly cooled down to room temperature at a rate of $10^{\circ}C$/h. In order to obtain single phase material, it was necessary to grind the sample after the first firing and to press the powders into pellets before annealing them for a second time in evacuated and sealed quartz ampoule. Magnetic properties have been investigated using the vibrating sample magnetometer (VSM). Room temperature magnetic hysteresis (M-H) curve showed an obvious ferromagnetic behavior and the magnetic moment per Fe atom under the applied of 0.8 T was estimated to be about $1.5\;{\mu}_B$/CoFe. But the magnetic moment per Fe atom under the applied of 0.8 T was estimated to be about $0.02\;{\mu}_B$/CoFe without Ti-getter. Size of particles is about $1\;{\mu}m$ using the transmission electron microscope (TEM). The ingredients of sample are distributed irregular in particles. Only Fe get shown on the surface of particles.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.164-176
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• 2012

In the present study, rapeseed flour (RSF), which is a by-product from the production of edible oil and biodiesel extracted from rapeseed, was used to develop alternative adhesives for the production of plywood panels. To examine the effects of the enzyme on the adhesive properties and formaldehyde emission of the RSF-based adhesive resins, three enzymes, such as cellulase (CEL), pectinase (PEC) and protease (ALC), were used either separately or together. As a crosslinking agent, PF prepolymers, which were prepared with 1.5, 1.8 and 2.1 mole formaldehyde and 1 mol phenol (1.8-, 2.1- and 2.4-PF), were added into the RSF hydrolyzates. The adhesive resins formulated with CEL- or CEL-PEC-RSF hydrolyzates and 1.8-F/P PF prepolymers exhibited excellent adhesive strengths and formaldehyde emission. The tensile shear strength and formaldehyde emission of the plywood panels bonded with the formulate resins were satisfied with the minimum requirement of the KS standard for ordinary plywood panels (0.6 N/$mm^2$). In addition, formaldehyde emissions of the plywood panels approached to that of E0 specified in the KS standard (0.5 mg/${\ell}$), and even had much better than those of commercial UF glue mixes. Overall, the use of RSF-based adhesive resins for the production of plywood panels might provide durable adhesive properties and an environmentally friendly substitute for petroleum-based adhesive resins. However, further researches - the increase of solid content of RSF-based adhesives for reducing press time and the microscopic observation of plywood specimen for identifying the relationship between tensile shear strength and the penetration of adhesives into wood structure - are required to commercialize the RSF-based adhesives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.598-604
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• 2012

Four types of mixed citrus and carrot juice (CCJ) were prepared with citrus-pressed juice and cake, and carrot-pressed juice. Their physicochemical properties and antioxidative activities were investigated. The four types of juices were created using different ratios of citrus-pressed juice, carrot-pressed juice, citrus-pressed cake, and additives. The mixing ratios of the four CCJ were as follows (all ratios given in the order of citrus-pressed juice : carrot-pressed juice : citrus-pressed cake : additives; 70:30:0:0 for CCJ-1, 65:30:0:5 for CCJ-2, 65:30:5:0 for CCJ-3, and 60:30:10:0 for CCJ-4. Acidity was low in CCJ-3 and -4 at 0.82 and 0.80, respectively, compared with 0.95 in CCJ-1. The fructose, glucose, and sucrose content was 2.11~5.76 g/100 g, 1.20~2.75 g/100 g, and 3.00~4.21 g/100 g, respectively. Total phenolic content was 1.17 and 1.22 times high as 863 and 898 mg% in CCJ-3 and -4, respectively, compared with 735 mg% in CCJ-1. DPPH radical scavenging activities of methanol extracts of CCJ-3 and -4 were 3.05 and 3.29 times as high as 58.7% and 63.3%, respectively, compared with 19.2% in CCJ-1. Superoxide anion scavenging activities were also 1.67 and 1.80 times higher in CCJ-3 and -4 than that of CCJ-1. Inhibition of NO production in methanol extracts of CCJ-4 were 1.15 and 1.57 times as high as 20.9% and 28.5%, respectively, compared with 18.2% in CCJ-1. Based on the sensory evaluation, CCJ-3 was more preferable in terms of color, flavor, taste, and overall preference than CCJ-1, -2, and -4. It was concluded that CCJ-3 made with 65% citrus-pressed juice, 30% carrot-pressed juice, and 5% citrus-pressed cake were high in antioxidative activity and the inhibition of NO production, and more preferable in terms of sensory attributes.

• Korean Journal of Cognitive Science
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• v.27 no.4
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• pp.573-597
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• 2016

Recent fMRI and EEG research for neural representations of action concepts insist that processing of action concepts evoke the simulation of sensory-motor information. Moreover, there are several behavioral studies showing that understanding of action verbs or sentences describing actions interfere or facilitate current action performance. However, it is unclear that online interaction between processing of action concepts and current action is based on the simulation of sensory-motor information, or other neural mechanisms. The present research aims to explore the underlying neural mechanism that how the perception of action language influence the performance of current action using high-spacial temporal resolution EEG and multiple source analysis techniques. For this, participants were asked to perform a cued-motor reaction task in which button-pressing hand action and pedal-stepping foot action were required according to the color of the cue, and we presented auditorily action verbs describing the responding actions (i.e., /press/, /step/, /stop/) just before the color cue and examined the interaction effect from the semantic congruency between the action verbs and the current action. Behavioral results revealed consistently a facilitatory effect when action verbs and responding actions were semantically congruent in both button-pressing and pedal-stepping actions, and an inhibitory effect when semantically incongruent in the button-pressing action condition. In the results of EEG source waveform analysis, the semantic congruency effects between action verbs and the responding actions were observed in the Wernicke's area during the perception of action verbs, in the anterior cingulate gyrus and the supplementary motor area (SMA) at the time when the motor-cue was presented, and in the SMA and primary motor cortex (M1) during action execution stage. Based on the current findings, we argue that perceived action verbs evoke the facilitation/inhibition effect by influencing the expectation and preparation stage of following actions rather than the directly activating the particular motor cortex. Finally we discussed the implication on the neural representation of action concepts and methodological limitations of the current research.