• Applied Chemistry for Engineering
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• v.22 no.4
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• pp.395-399
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• 2011

Material of the gasket for lithium ion battery requires the chemical resistance, the electrical insulting property, the compression set, the anti-contamination level and the low temperature resistance. We compounded ethylene propylene diene monomer (EPDM), which showed widely different solubility parameter index, with adjusting the amount of metal oxide as an activator. We did long-term test and compression set against an electrolyte with consideration for operating conditions in lithium-ion battery. In these tests, we checked the physical, chemical characteristics and the effect to lithium ion battery with different kinds of activators. In case of rubber with ZnO as an activator, through 1000 h depositing test in propylene carbonate which is one of representative solvents, we could get the satisfying characteristics and result. However, $Zn^{2+}$ had eluted in the ion elution test. So, ZnO should be limited in EPDM compound for the gasket material in lithium-ion battery.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.1
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• pp.15-25
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• 2022

This study was conducted to provide useful basic data for restoration and maintenance of the Changdeokgung Palace(昌德宮)'s inner palace area in the future by exploring the background of terraced flower beds installed in the front space of Seunghwaru(承華樓) and grasping the reality before and after terraced flower beds were installed. The main results of this study can be summarized as follows. First, in the early 1900s, the front space of Seunghwaru formed a relatively higher terrain than the Nakseonjae(樂善齋) area. In addition, along the topography of high north and low south, a yard surrounded by Haenggak(行閣) and a rectangular open space connected to the West Haenggak of Nakseonjae were created. In particular, the rectangular open space was a staircase-type slope in which rectangular stone columns were arranged at regular intervals. Second, the terraced flower beds of Seunghwaru originated from the renovation of the new building of Nakseonjae West Hanggak, which was implemented in the late 1920s. This is because in order to secure enough available land for construction and auxiliary space during the renovation of the new building, the terraced flower beds for topographic treatment was created along the cutting area after cutting off the original topography of the front space of Seunghwaru. Third, after the construction of the terraced flower beds, many deformation occurred in the topographic features of the front space of Seunghwaru. The front yard of Seunghwaru was relatively higher than the Nakseonjae area, but most of them were cut off and disappeared as the terraced flower beds were created. The staircase-type also disappeared after the construction of the new building and terraced flower beds. The stylobate and front fence of Seunghwaru were newly built along the alignment of terraced flower beds and the unique style of narrow gate and auxiliary stairs were also relocated to the new fence.

• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.10-21
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• 2000

Purpose: Episodic memory is described as an 'autobiographical' memory responsible for storing a record of the events in our lives. We performed functional brain activation study using ${H_2}^{15}O$ PET to reveal the neural basis of the encoding and the retrieval of episodic memory in human normal volunteers. Materials and Methods: Four repeated ${H_2}^{15}O$ PET scans with two reference and two activation tasks were performed on 6 normal volunteers to activate brain areas engaged in encoding and retrieval with verbal materials. Images from the same subject were spatially registered and normalized using linear and nonlinear transformation. Using the means and variances for every condition which were adjusted with analysis of covariance, t-statistic analysis were performed voxel-wise. Results: Encoding of episodic memory activated the opercular and triangular parts of left inferior frontal gyrus, right prefrontal cortex, medial frontal area, cingulate gyrus, posterior middle and inferior temporal gyri, and cerebellum, and both primary visual and visual association areas. Retrieval of episodic memory activated the triangular part of left inferior frontal gyrus and inferior temporal gyrus, right prefrontal cortex and medial temporal area, and both cerebellum and primary visual and visual association areas. The activations in the opercular part of left inferior frontal gyrus and the right prefrontal cortex meant the essential role of these areas in the encoding and retrieval of episodic memory. Conclusion: We could localize the neural basis of the encoding and retrieval of episodic memory using ${H_2}^{15}O$ PET, which was partly consistent with the hypothesis of hemispheric encoding/retrieval asymmetry.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.3
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• pp.205-213
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• 2005

To evaluate the reliability of binocular vision measurements by phorometry. 90 students volunteered to participate in this study. 25 subjects were males, and 65 were females, they ranged in ages from 21 to 30 years. All subjects had normal ocular and systematic health, and all of them had at least 1.0 visual acuity with their best correction. At negative relative convergence(NRC) measurement in distance, the percentage of subjects is included in expected value(blur point/break point/recovery point) was 78%/61%/67%, divergence excess(DE) was 9%/31%/33%, and divergence insufficience(DI) was 13%/8%/9%, respectively. And positive relative convergence(PRC) measurement, includes expected value was 20%/46%/39%, convergence excess(CE) was 22%/14%/16%, and convergence insufficience(CI) was 35%/40%/45%. AC/A ratios of 42 subjects were normal. 38 were low, and the rest of them high. A low AC/A ratio is usually the result of a small vergence response in relation to accommodation. Negative relative convergence(NRC) at near, includes expected value was 26%/29%/44%, divergence excess(DE) was 61%/33%/24%, and divergence insufficience(DI) was 3%/38%/32%. And PRC at near, includes expected value was 33%/40%/31%, convergence excess(CE) was 61%/23%/42%, and convergence insufficience(CI) was 6%/37%/27%. For the near point of convergence(NPC) test, 58% of their subjects had a break of ${\leq}8cm$ with the accommodative target. In case of NRA(PRA) measurement, the expected value was 41%(33%). Accommodative insufficiency (AI) was 33%(43%), and accommodative excess(AE) was 26%(24%), respectively. AE was related to respectively low values of NRA. AI and CE are associated with high value of NRA, and the dysfunction of convergence excess combined with AE was related to a normal-high values of NRA. PRA in AI was related to a low value, wheres the dysfunction are associated with high values of PRA.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.89-97
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• 2007

A three-dimensional (3D) magnetotelluric (MT) survey has been carried out to delineate subsurface structures and possible fractures, for development of low-temperature geothermal resources in Pohang, Korea. Quite good quality MT data could be obtained throughout the survey region by locating the remote reference in Kyushu, Japan, which is ${\sim}480\;km$ from the centre of the field site. 3D modelling and inversion are performed taking into account the sea effect in MT measurements near the seashore. The nearby sea in the Pohang area affects MT data at frequencies below $1\;Hz{\sim}0.2\;Hz$, depending on the distance from the seashore. The most severe sea effects were observed in the south-east parts of the survey area, closer to Youngil Bay. 3D inversion with and without the seawater constraint showed very similar results at shallow depths, roughly down to 2 km. At greater depths, however, a strong sea effect seems to form a fictitious conductive structure in ordinary 3D inversion, especially in the south-eastern part of the survey region. Comparison between drilling results and the resistivity profiles from inversions showed that five layered structures can be distinguished the subsurface beneath the target area. They are: (a) semi-consolidated mudstones with resistivity less than $10\;{\Omega}m$, which are ${\sim}300\;m$ thick in the northern part and ${\sim}600\;m$ thick in the southern part of the survey area; (b) occasional occurrence of trachybasalt and lapilli tuff within the mudstone layer has resistivity of a few tens of${\Omega}m$, (c) intrusive rhyolite ${\sim}400\;m$ thick has resistivity of several hundreds of ${\Omega}m$, (d) alternating sandstone and mudstone down to 1.5 km depth shows resistivity of ${\sim}100\;{\Omega}m$, (e) a conductive structure was found at a depth of ${\sim}3\;km$, but more geological and geophysical study should be carried out to identify this structure.

• Journal of Life Science
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• v.18 no.11
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• pp.1532-1537
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• 2008

The purpose of this study was to investigate the effect of different arthroplasty designs on knee kinematic and lower limb muscular activation for up-stair and down-stair movement. 3-D video analysis of whole body and joint kinematics and EMG analysis of quadriceps and hamstrings were conducted. One-way ANOVAs were used for statistical analyses (p=0.05). The single-radius group exhibited more arthroplasty limb quadriceps EMG and hamstring coactivation EMG than the multi-radius group. Single-radius demonstrated more abduction angular displacement and reached peak abduction earlier than the multi-radius arthroplasty limb. The single- radius the percent body fat showed similar values in the Elderly, Single and Multi-radius group among the periods, however Control group was Lowered among the periods. Single-radius group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. Resting metabolic rate was significantly increased in control group in the period of LI. Energy expenditure was extremely increased in all groups except control group among the periods. We can say this is the exercise effects.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.230-236
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• 2010

Purpose: We wanted to evaluate the result of percutaneous, mini-open reduction for the treatment of Mason II or III radial head and neck fractures. Materials and Methods: 13 patients (8 male, 5 female) with Mason II or III radial head and neck fractures were treated by 1 cm percutaneous mini-open reduction under fluoroscopy. The average age of our subjects was 29 years. Follow up duration was 18 months. Results: Union was noted in all cases. Mean radial neck angulation was decreased from 33.2 degrees to 7.8 degrees. The mean change in angulation between the immediate post-operative and last follow-up was 0.7 degrees. The mean range of motion at the elbow joint was at last follow up, 133.1 degrees in flexion, 7.3 degrees in extension, 80 degrees in pronation and 84.3 degrees in supination. Postoperatively, mean Mayo Elbow Performance Index, American Shoulder and Elbow Surgeons elbow score, and Disabilities of the Arm, Shoulder and Hand score were 96.2, 97 and 1.2. Temporary posterior interosseous nerve palsy (1 case) and minimal cubitus valgus deformity (1 case) were noted. Conclusion: Selected Mason II or III radial head and neck fractures can be treated satisfactorily with percutaneous mini-open reduction.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.159-166
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• 2009

Purpose: We wanted to evaluate the surgical results of early mobilization after rigid fixation of small coronoid fracture using the tension band technique Materials and Methods: Eight cases of coronoid fracture were fixed with the tension band technique and using K-wire and wire through the medial approach. All the cases were Regan-Morrey type 2. According to O'Driscoll, they were classified as 5 cases of the tip type (subtype 2) and 3 cases of the anteromedial type (1 case of subtype 2, and 2 case of subtype 3). The associated collateral ligament injuries (6 cases) and radial head/neck fractures (4 cases) were managed simultaneously. After immobilization for 5~7 days, active ROM exercise with a fitted hinge brace started and continued till postoperative 6 weeks. The patients were assessed for pain, ROM and functional disability using the Mayo elbow performance score (MEPS) at an average of 11 months (range: 6~28 months). The ulnar nerve symptoms were also investigated. Results: We observed solid union in all the coronoid fractures without hardware failure. An average of 2.2 wires (range: 2~4) were used. The mean extension was $3^{\circ}$(range: $0^{\circ}\sim25^{\circ}$), the mean flexion was $137^{\circ}$(range: $130^{\circ}\sim140^{\circ}$), the mean pronation was $69^{\circ}$(range: $45^{\circ}\sim90^{\circ}$) and the mean supination was $78^{\circ}$(range: $45^{\circ}\sim90^{\circ}$). The mean MEPS was 96 (range: 65~100). Ulnar nerve symptoms occurred at postoperative one day and persisted in one patient with the terrible triad of taking radial head excision and residual medial instability. Conclusion: The tension band technique uses easily obtained, economic K-wires and the wire was strong enough to permit early elbow ROM exercise and the technique might improve the elbow function. It was especially useful for fixation of multiple small fragments.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.3
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• pp.1-10
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• 2020

The purpose of this study is to identify whether the cranes had been bred in the palace of the Joseon Dynasty period and to consider the related cases. The temporal range of this study is in the Joseon Dynasty period, and the spatial range is throughout the entire palace, including the naejeon(內殿) and oijeon(外殿), and government offices inside(闕內各司) and government offices outside(闕外各司). The reference materials for this study were partly extracted and translated from the original documents to consider, and a Korean version of documents was used in the database of the Institute for the Translation of Korean Classics. The results of this study are summarized as follows. First, the cranes were bred from the early Joseon Dynasty Era in Uijeongbu, the highest government office in the Joseon Dynasty period. After the Japanese Invasion of Korea in 1592, crane breeding in Uijeongbu(議政府) seems to have been suspended due to the damage to the government building and the change in the status of the government office. Second, crane breeding in Hongmungwan(弘文館), which was responsible for the classics colloquium(經筵) and public opinions and assisted the king by the side, continued from the early Joseon Dynasty period(Jungjong's Era) to the late Joseon Dynasty period(Jeongjo's Era) after the Japanese Invasion of Korea in 1592. Third, in the Jeongjo's Era, the cranes were also bred in Gyujanggak(奎章閣), which was newly established as the central institution of learning to strengthen the royal authority. At that time, it seems that several cranes were bred in Gyujanggak. Fourth, it is judged that 'Crane breeding' in the core government offices of Joseon, such as Uijeongbu, Hongmungwan, and Gyujanggak, was meaningful as a symbol of identities, such as the status and character of the institution. Fifth, it seems that the cranes bred in the palace, including Hongmungwan, were conventionally brought by the Baecheon County of Hwanghae-do. This convention caused minor conflicts between the central and local government offices during the Yeongjo's Era, but it seems to have continued throughout the Jeongjo's Era. In this study, there is a limit that most of the studies were conducted based on local data. If further data discovery and translation outcomes are accumulated in the future, more abundant cases will be identified. The deepened follow-up studies are also needed, other than the cases of rearing cranes in the local government offices and temples.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.174-191
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• 2021

Gangdo (江都), a reproduction of Gaegyeong, was the capital of Goryeo for 39 years. However, due to the urgent wartime situation of the Mongol invasion and the geographical features of Ganghwa Island, the castle system and palace layout were somewhat different from those of Gaegyeong. Gangdo's castle can be understood as a triple castle system consisting of outer castle, middle castle, and inner castle. First, the outer castle was the first to be completed, and it was built at the forefront to prevent the Mongol army from invading in the first place. It is presumed that the section was between Huamdon and Hwadodon in the outer castle during the Joseon Dynasty. The middle castle can be seen as the present 'Middle Castle', a castle built of earth on the outskirts of the Ganghwa-mountain Castle. Considering the sophistication and robustness of the construction method confirmed in the archaeological research, this castle is thought to have been built under a meticulous plan. In other words, as the capital city, it was completed 'at last' as recorded in the Koryo History, after a long 18-year construction process to protect palaces, government offices, and private houses. The inner castle was a castle with the character of a palace. This corresponds to the Old Castle of Ganghwabu (江華府) during the Joseon Dynasty, and it almost coincided with the scale of the composition of Gaegyeong's palace castle. It was a complex functional space, featuring the integration of the palace and the imperial castle, where the main government offices and ancillary facilities, including the palace, were located. Based on the documentary record that these palaces were similar to Gaegyeong's palace, the palace map was overlapped with that of Gaegyeong. The central axis of the building from Seungpyeongmun (昇平門) to Seongyeongjeon (宣慶殿) coincided with Kim Sangyongsunjeol Monument in Ganghwa- Goryeo Palace. Therefore, it seems that the palace of Gangdo had the same basic structure as that of Gaegyeong. However, the inner palace and annexed buildings must have been arranged in consideration of the topographical conditions of Ganghwa, and this is estimated to be the Gunggol area in Gwancheong-ri.