• Journal of Korean Society of Steel Construction
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• v.23 no.2
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• pp.237-247
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• 2011

This paper presents an improved initial force method for determining the initial shape of suspension bridges. After determining the initial shape factors through the force equilibrium conditions of each hanging point, the initial force method was applied with the computed values, each node's coordinates, and unstrained lengths of the cable element as inputs. The unstrained length of each cable element was regarded as a fixed value in each iteration step, unlike in the typical initial force method. This method can be applied to 2D and 3D suspension bridge models. The validity of the present method was demonstrated by comparing the results of the numerical examples.

• YAKHAK HOEJI
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• v.58 no.5
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• pp.300-306
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• 2014

Ethanol consumption causes psychomotor alterations. Hovenia Semen seu Fructus (HS), widely distributed in Korea, China, and Japan, has been reported to have beneficial effects on acute alcohol-induced liver injury. The present study sought to assess the effects of HS extract on ethanol-induced psychomotor alterations in rats. Sprague-Dawley rats were orally (p.o.) given ethanol (4 g/kg) (ethanol group) to induce psychomotor alterations. A separate group (HS-treated groups), were treated with different dosages of HS (50, 100, and 200 mg/kg, p.o.), 30 minutes before ethanol treatment. The control group received only the vehicle (saline). Ethanol-induced psychomotor alterations were evaluated in the open-field, rota-rod, hanging wire, and cold swimming test. In addition, blood ethanol and acetaldehyde concentrations were also measured. Behavioral evaluations and blood analysis were carried out 0.5, 1, 2, 4, and 8 hours after ethanol administration. Pre-treatment of HS ameliorated ethanol-induced alterations in the open-field, rota-rod, and cold swimming test, significantly evident in 2 and 4 hours after ethanol treatment. These improvements coincided with decrease in blood ethanol and acetaldehyde concentration. Based on these results, the present study suggests that HS may have ameliorating effects against ethanol-induced psychomotor alterations.

• Journal of Integrative Natural Science
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• v.6 no.4
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• pp.193-196
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• 2013

Haemoglobin is an interesting physiologically significant protein composed of specific functional prosthetic haem and globin moieties. In recent decades, there has been substantial interest in attempting to understand the structural basis and functional diversity of avian haemoglobins (Hbs). Towards this end, purification, crystallization, preliminary X-ray diffraction and molecular-replacement studies have been carried out on Amaurornis phoenicurus Hb. Crystals were grown by the hanging drop vapor-diffusion method using PEG 2000 and NaCl as precipitants. The crystals belonged to the primitive monoclinic system $P2_1$, with unit-cell parameters $a=65.33{\AA}$, $b=93.14{\AA}$, $c=98.54{\AA}$, ${\beta}=100.48^{\circ}$; a complete data set was collected to a resolution of $2.6{\AA}$. The Matthews coefficient of $2.30{\AA}^3Da^{-1}$ for the crystal indicated the presence of two ${\alpha}_2{\beta}_2$ tetramers in the asymmetric unit.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.175-184
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• 2021

Objective: Fatigue can decrease both quality of life and work efficiency. Ginseng is one of the most popular herbal treatments for improving personal health, with applications in treating fatigue. However, the exact mechanisms of anti-fatigue effects are still unclear. Thus, we investigated the effect of red ginseng powder (RGP) on exercise capacity and peripheral fatigue using both behavioral and molecular experiments in mice. Design: Four-groups behavioral and molecular experiment. Methods: Male 6-weeks-old ICR mice were treated with distilled water, 100, and 200 mg/kg RGP for 5 days via oral administration. The exercise capacity of each animal group was measured by locomotor activity, rota-rod, hanging wire, and cold swimming tests. Additionally, after performing the treadmill to induce fatigue, lactate expression and molecular experiments were investigated using mice gastrocnemius. Results: Mice treated with RGP exhibited increased exercise capacity in the behavioral tests. Additionally, RGP induced a dose-dependent decrease in lactate levels after high-intensity exercise, and Monocarboxylate transporter (MCT) 4 expression increased in groups treated with RGP. However, there was no significant change in MCT1. Conclusions: These results suggest that RGP exerts several anti-fatigue properties by lower lactate and improved exercise capacity. Increased MCT4 expression may also affect lactate transport. Thus, this study suggests that the anti-fatigue properties of RGP might be associated with MCT4 activity.

• Journal of Audiology & Otology
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• v.25 no.1
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• pp.43-48
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• 2021

Background and Objectives: Conflicting mechanisms have been reported about spontaneous reversal of positional nystagmus during head-roll maneuver in patients with benign paroxysmal positional vertigo (BPPV). The objective of this study is to review the reports about the characteristics and possible mechanisms of reversing positional nystagmus and to present seven new cases. Subjects and Methods: Seven cases (5 males, 2 females; 4 left-sided, 3 right-sided) were recruited among 732 patients with BPPV seen outpatient clinic between 2009 and 2019. Diagnosis of lateral canal canalolithiasis was confirmed when transient geotropic nystagmus was documented during head-roll test. Reversing positional nystagmus was analyzed in each case and clinical characteristics of the patients were documented. Results: The age of patients was ranging between 30 to 64 years (46.44±10.91). Duration of symptoms was short (21.34±19.74). Six of them had a story of head trauma. Initial latency was short. First, intense geotropic nystagmus was observed following provocative head-roll position on the affected side. There was short "silent phase". Then, a longer second-phase of reversed nystagmus was noted. Total duration of nystagmus was 78.40±6.82 seconds. Maximal slow phase velocity was 24.05±6.34 deg/sec. All patients were cured with barbeque maneuver. Conclusions: Ipsilateral reversing positional nystagmus during head-roll maneuver is due to lateral canal canalolithiasis. Mechanism is likely to be due to endolymphatic double flow. Bilateral cases may be due to simultaneous co-existence of canalolithiasis and cupulolithiasis. Longer recording of nystagmus is recommended not to miss the cases with spontaneous direction-changing positional nystagmus.

• Korean Journal of Audiology
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• v.25 no.1
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• pp.43-48
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• 2021

Background and Objectives: Conflicting mechanisms have been reported about spontaneous reversal of positional nystagmus during head-roll maneuver in patients with benign paroxysmal positional vertigo (BPPV). The objective of this study is to review the reports about the characteristics and possible mechanisms of reversing positional nystagmus and to present seven new cases. Subjects and Methods: Seven cases (5 males, 2 females; 4 left-sided, 3 right-sided) were recruited among 732 patients with BPPV seen outpatient clinic between 2009 and 2019. Diagnosis of lateral canal canalolithiasis was confirmed when transient geotropic nystagmus was documented during head-roll test. Reversing positional nystagmus was analyzed in each case and clinical characteristics of the patients were documented. Results: The age of patients was ranging between 30 to 64 years (46.44±10.91). Duration of symptoms was short (21.34±19.74). Six of them had a story of head trauma. Initial latency was short. First, intense geotropic nystagmus was observed following provocative head-roll position on the affected side. There was short "silent phase". Then, a longer second-phase of reversed nystagmus was noted. Total duration of nystagmus was 78.40±6.82 seconds. Maximal slow phase velocity was 24.05±6.34 deg/sec. All patients were cured with barbeque maneuver. Conclusions: Ipsilateral reversing positional nystagmus during head-roll maneuver is due to lateral canal canalolithiasis. Mechanism is likely to be due to endolymphatic double flow. Bilateral cases may be due to simultaneous co-existence of canalolithiasis and cupulolithiasis. Longer recording of nystagmus is recommended not to miss the cases with spontaneous direction-changing positional nystagmus.

• Journal of People, Plants, and Environment
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• v.24 no.4
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• pp.365-376
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• 2021

Background and objective: This study aims to develop and apply programs in agriculture and life sciences for promoting divergent thinking in STEAM using classroom wall gardens. The process of the STEAM program such as presentation of the situation, creative design, and success experience is proposed to utilize STEAM education as a distinguished program. Methods: Four types of classroom wall gardens were used in this program, such as the 'plaster pot wall garden', 'attachable LED wall garden'. 'coffee pack wall garden', and 'hanging wall garden' for each classroom. For this purpose, official letters were sent to relevant institutions (elementary schools) specified by the research institute, and classes were conducted on the selected elementary school students. Results: A satisfaction survey and effect analysis were conducted on the students participating in the program. The program was designed to take a total of 11 hours, comprised of teaching plans including the topics, purpose of production, subject outlines, learning goals, and elements of STEAM subjects and stages. Conclusion: According to the survey on student satisfaction and understanding, it was found that students participating in the program have a high level of understanding and participation, as well as increased interest in science. Also, the program helped the students to connect with other subject areas. The level of student satisfaction was especially high in the upper grades. It is believed that the results of this research contribute to the development of STEAM education programs in agriculture and life sciences as well as other subject areas.

• Journal of Dental Anesthesia and Pain Medicine
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• v.23 no.1
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• pp.39-43
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• 2023

Nasotracheal intubation is commonly performed under general anesthesia in oral and maxillofacial surgery. For the convenience of surgery, nasal Ring-Adair-Elwyn (RAE) tubes are mainly used. Because the nasal RAE tubes were bent in an "L" shape, the insertion depth was limited. Particularly, it is necessary to accurately determine the appropriate depth of the RAE tubes in children. Several types of nasal RAE tubes are used in the medical market, which vary in material and length. We performed endotracheal intubation using a nasal RAE tube for double-jaw surgery, but air leakage persisted even when the air pressure in the cuff was increased. When checked with a laryngoscope, it was confirmed that the tube was pushed out, and the cuff was caught on the vocal cords, causing air leakage. Since inserting the tube deeply did not solve the problem, replacing it with a nasal RAE tube (Polar^TM, Preformed Tracheal Tube, Smith Medical, Inc., USA) did not cause air leakage; thus, we reported this case.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.788-793
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• 2009

Constructing substructures by using Top-Down or Downward method needs an efficient formwork system because of difficulties in supporting concrete slabs from the bottom while excavation is in process. Existing underground formwork systems can be classified by three types: graded ground supported type (Slab On Grade, Beam On Grade), suspension type (Non Supporting Top Down Method), and bracket supported type (Bracket Supported R/C Downward). Each method has its own advantages and limits. Application of a specific formwork system for a given construction site is determined by various conditions and affect construction time and cost. This paper presents a newly developed underground non-supporting formwork system, which combines the advantages of a suspension type and a bracket supported type while it overcomes limits of two types. The developed system has a moving formwork which is supported by suspension cables hanging from the bracket placed at the top of pre-installed substructure columns. Then, the moving formwork is repeatedly lowered down for the next floor below to support concrete slab during curing. The details of this bracket and cable supported system have been investigated for the improvement of easiness in construction.

• Journal of the Korea Safety Management & Science
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• v.25 no.3
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• pp.31-36
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• 2023

The use of hanging scaffolding for exterior wall painting and cleaning in building construction and maintenance carries the inherent risk of fall accidents. While periodic rope replacement is crucial for preventing accidents resulting from rope breakage, current regulations lack specificity in determining appropriate disposal period for fiber ropes. This study analyzed the tensile strength of the most commonly used PP fiber ropes with different diameters (16 mm, 20 mm) in the domestic construction industry. Additionally, the effect of outdoor exposure was examined by measuring the tensile strength of new ropes and ropes exposing to outdoor conditions for 30 days and 90 days. The results showed that the new ropes and those exposed to outdoor for 30 days met the KS (Korean Standards) criteria for tensile strength. However, a significant decrease in tensile strength was observed in ropes exposed to outdoor for 90 days compared to both the new ropes and those exposed for 30 days. Furthermore, the ropes exposed for 90 days did not meet the KS criteria. These findings indicate the degradation of PP fiber ropes due to UV (Ultra Violet) radiation, highlighting the importance of considering this factor when determining the replacement period for fiber ropes used in scaffolding work.