• Korean Journal of Crystallography
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• v.2 no.2
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• pp.13-21
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• 1991

X-ray methods have been used to determine the chain conformation and packing of the thermotropic liquid crystalline copolyester prepared from 50% tarephthaloyl chloride(TPA) and 50% (1-phenylethyl) hydroquinone(PEHQ). The x-ray patterns of annealed melt-spun fibers contain a series of annealed melt-Pointing to a well ordered crystalline structure, despite the random sense(2 or 3-) of the 1-phenylethyl substiuttion on the TPA-hydroquinone backbone. The crystalline fiber is monoclinic with space group P2l and the unit cell has dimensions 11=12.77 A, b=10.17 A (upique axis), c=12.58 h (fiber axis). and β=90.1° and contains TPA-PEHO units of to or chains. The random substitution of 1-phenylethyl groups was modelled by placing these groups at both the 2and 3 positions and giving each a weight of one-hal(. T he structure has been refined by linked a rom least square methods(LALS) against 16 observed and 21 unobserved reflections. and had a final R value of 0.20. Packing of the side chains is effected by staggering adjacent chains along the b axis by approximately c/2, so that the side chains are interleaved. The phenyl-COO and COO-phenyl torsion angles are -6.1 and 65.6, respectively, such that the main chain phenyls are mutually inclined at 59.5 (the ester groups are assumed to be planar). These torsion angles compare very well with those for the model compounds, notably phenylbenzoate, and can be used in future analyses of the structures of more complex random sequence copolyesters.

• Geophysics and Geophysical Exploration
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• v.14 no.4
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• pp.298-304
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• 2011

We conducted magnetic survey using IBRV (Ice Breaker Research Vessel) ARAON of KORDI (Korea Ocean Research and Development Institute), ROV (Remotely Operated Vehicle) of Oceaneering Co. and three components vector magnetometer, at Apr., 2011 in the western slope of the caldera of TA25 seamount, the Lau Basin, the southwestern Pacific. The depth ranges of the survey area are from about 900 m to 1200 m, below sea level. For the deep sea magnetic survey, we made the nation's first small deep sea three components magnetometer of Korea. The magnetometer sensor and the data logger was attached with the upper part and lower part of ROV, respectively. ROV followed the planning tracks at 25 ~ 30 m above seafloor using the altimeter and USBL (Ultra Short Base Line) of ROV. The three components magnetometer measured the X (North), Y (East) and Z (Vertical) vector components of the magnetic field of the survey area. A motion sensor provided us the data of pitch, roll, yaw of ROV for the motion correction of the magnetic data. The data of the magnetometer sensor and the motion sensor were recorded on a notebook through the optical cable of ROV and the network of ARON. The precision positions of magnetic data were merged by the post-processing of USBL data of ROV. The obtained three components magnetic data are entirely utilized by finding possible hydrothermal vents of the survey area.

• Progress in Medical Physics
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• v.9 no.1
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• pp.1-9
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• 1998

In order to provide complementary image data, CT(computed tomography), MR(magnetic resonance) and angiography have been used in the field of Stereotactic Radiosurgery(SRS) and neurosurgery. The aim of this work is to develop 3-D stereotactic localization system in order to determine the precise shape, size and location of the lesion in the brain in the field of Stereotactic Radiosurgery(SRS) and neurosurgery using multi-image modality and multi purpose QA phantom. In order to obtain accurate position of a target, Hitchcoke stereotactic frame and CT/angiography localizers were rigidly attached to the phantom with nine targets dispersed in 3-D space. The algorithms to obtain a 3-D stereotactic coordinates of the target have been developed using the images of the geometrical phantom which were taken by CT/angiography. Positions of targets computed by our algorithms were compared to the absolute position assigned in the phantom. Outlines of targets on each CT image were superimposed each other on angiography images. A spatial mean distance errors were 1.02${\pm}$0.17mm for CT with a 512${\times}$512 matrix and 2mm slice thickness, 0.41${\pm}$0.05mm for angiogra- phy localization. The resulting accuracy in the target localization suggests that the developed system has enough Qualification for Stereotactic Radiosurgery (SRS).

• Progress in Medical Physics
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• v.26 no.3
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• pp.153-159
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• 2015

This study is to evaluate thedosiemtric leaf gap (DLG) at different depths for dynamic intensity-modulated radiation therapy (IMRT) in order to evaluate the absolute dose and dose distribution according to the different positions of tumors and compare the measured and planned the multileaf collimator (MLC) transmission factor (T.F.) and DLG values. We used the 6 MV and 15 MV photon beam from linear accelerator with a Millenium 120 MLC system. After the import the DICOM RT files, we measured the absolute dose at different depths (2 cm, 5 cm, 10 cm, and 15 cm) to calculate the MLC T. F. and DLG. For 6 MV photon beam, the measured both MLC T. F. and DLG were increased with the increase the measured depths. When applying to treatment planning systemas fixed transmission factor with its value measured under the reference condition at depth of 5 cm, although the difference fixed and varied transmission factor is not significant, the dosiemtric effect could be presented according to the depth that the tumor is placed. Therefore, we are planning to investigate the treatment planning system whichthe T. F. and DLG factor according to at the different depths can be applied in the patient-specific treatment plan.

• Journal of the Korean Geographical Society
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• v.50 no.3
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• pp.289-303
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• 2015

This paper is an introductory research to theorize women migrants' positionality in the era of globalization and the feminization of migration. It particularly examines three recent theoretical approaches within feminist studies and their application to the feminist migration study. Migration means a process of continuous negotiations of one's social and material positions within ever changing relations and situations through crossing various borders including national boundaries. Women migrants face multifaceted oppressions due to gendered relation and greater challenges to transform their identities. They embody politics of location through migration. The paper revolves around theories that explore a potential of feminist subjectivation of marginalized women such as female migrants through their identity negotiation and transformation. The theories in questions are Borderlands and the New Mestiza introduced by Gloria $Anzald{\acute{u}}a$, Intersectionality of oppressions, and Transpositions and the Nomadic Subjects by Rosi Braidotti who borrowed the theories of Deleuze and Guattari through feminist critiques. These theories all represent power relations and subject transformations through spatial metaphors. rough spatialized understandings, the paper proposes interlocking relations among space, gender and migration, and explores conceptual tools as well as epistemological insights for Korean migration study.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.371-380
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• 2017

PURPOSE. The aim of this study is to evaluate and compare the stress distribution in Locator attachments in mandibular two-implant overdentures according to implant locations and different loading conditions. MATERIALS AND METHODS. Four three-dimensional finite element models were created, simulating two osseointegrated implants in the mandible to support two Locator attachments and an overdenture. The models simulated an overdenture with implants located in the position of the level of lateral incisors, canines, second premolars, and crossed implant. A 150 N vertical unilateral and bilateral load was applied at different locations and 40 N was also applied when combined with anterior load at the midline. Data for von Mises stresses in the abutment (matrix) of the attachment and the plastic insert (patrix) of the attachment were produced numerically, color-coded, and compared between the models for attachments and loading conditions. RESULTS. Regardless of the load, the greatest stress values were recorded in the overdenture attachments with implants at lateral incisor locations. In all models and load conditions, the attachment abutment (matrix) withstood a much greater stress than the insert plastic (patrix). Regardless of the model, when a unilateral load was applied, the load side Locator attachments recorded a much higher stress compared to the contralateral side. However, with load bilateral posterior alone or combined at midline load, the stress distribution was more symmetrical. The stress is distributed primarily in the occlusal and lateral surface of the insert plastic patrix and threadless area of the abutment (matrix). CONCLUSION. The overdenture model with lateral incisor level implants is the worst design in terms of biomechanical environment for the attachment components. The bilateral load in general favors a more uniform stress distribution in both attachments compared to a much greater stress registered with unilateral load in the load side attachments. Regardless of the implant positions and the occlusal load application site, the stress transferred to the insert plastic is much lower than that registered in the abutment.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.246-253
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• 2016

The optimal time for the removal of supernumerary teeth can be divided into two groups; early removal and late removal. While each group has its own advantages, the effects on maxillary central incisor can be significant. The purpose of this study was to determine the ideal time for the removal of the supernumerary teeth by evaluating 166 patients for three months after surgical removal of supernumerary teeth. Relatively young patients in early Hellman's dental stage with less developed or unerupted maxillary central incisor had less midline deviation. No statistical significance was found in diastema, rotation of the maxillary incisors and their changes during a follow-up period. Removal of supernumerary teeth should be considered as a preventative measure prior to eruption of the maxillary incisors when the midline deviation is observed in panoramic radiographic examination. This study will be useful in determining the optimal time for the removal of supernumerary teeth depending on the location of the maxillary incisors. This study will be informative on deciding the optimal time to remove the supernumerary teeth depending on the various positions of the maxillary central incisor. (this sentence is better to use)

• Korean Journal of Social Welfare
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• v.69 no.1
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• pp.147-174
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• 2017

This study is aimed at examining the rights of students who are under social work field practicum, as trainees, in the aspect of the rights to learn and the rights to work, in particular. This study utilized FGI method, and a total of 18 trainees participated. As a result, awareness of students who joined social work field practicum was reduced to five categories in total and 19 sub-categories. The results is as following. First, social work field trainees did not aware of their rights. Second, the field trainees were taking the role with double positions as a trainee and a worker, and experiencing confusion and difficulties thereof. Third, they were not provided proper instructions as trainees, and feeling burden therefrom. Fourth, even though the students were providing actual labor at the field, they felt anxiety and unfairness because they were not properly protected when they were faced with issues regarding reasonable reward and safety. Fifth, due to such difficulties, students were demanding that field organizations and schools make positive efforts to improve awareness about protection of the rights. Based on such results, offered basic data for field training improvement plans and intended to explore alternative plans for improvement of social work field practicum.

• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.136-144
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• 1999

Crystal structures of tungsten-bronze type microwave dielectric ceramics, $BaOLa_2O_34TiO_2$ (BLT) and $BaO(Nd_{0.77}Y_{0.23})_4TiO_2$ (B(NY)T), were analysed using the Rietveld method. The most relibale refinement was obtained by refining the cation and anion positions from the x-ray and neutron diffraction data, respectively. The ambiguites inherent in the refined crystal structure by Mateeva et al. were resolved. The $BaORe_2O_34TiO_2$ structure consiste of $3\times2$ perovskite blocks and 4 pentagon-channels. The Ti-O6 octahedrons are distroted and tilted, which, consequently, induces the displacements of Ba and Re ions producing the superlattics (c$\approx$ 7.6 $\AA$). The B(NY)T showed more severely tilted Ti-O6 octahedrons. The relative dielectric constant $\varepsilon_{\gamma}$ and temperature coefficient $\tau_\varepsilon$ are 109.5 and-$180 ppm/^{\circ}C$ in BLT, 76 and $+40 ppm/^{\circ}C$ in B(NY)T, respectively. The small Re ions produced a positive $\tau_\varepsilon$. The relation between $\tau_\varepsilon$ and the octahedron tilting in complex perovskite is discussed for the tungsten bronze type structure.

• Journal of Korean Academy of Nursing
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• v.4 no.1
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• pp.22-37
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• 1974

Through the examination of hospitalized patient's records, this study purports to determine. the extent to which nursing record behaviors meet general expectations held for nursing records and the differences in nursing record behavior in relation to different nursing categories, period of recording and hospitals with different management patterns. Nursing record behaviors of 802 patient's records in four hospitals in Seoul were examined. by use of a check list, which was prepared by the author as an instrument for the study. Data obtained from this examination were processed into percentage values for percentage. test and chi-square test in order to determine their significance. Results are as follows; 1. Records pertaining to treatment ranked highest among all care categories in their extent of coverage, averaging 65.6 percent. 2. Of the treatment category records, records of medication led others at 94.3 percent. followed by records of test and collection of specimens at 59.9 percent. diet at 58.8 percent and treatment at 41.0 percent. 3. Records in the category of physical assessment and care averaged 44.1 percent, the second highest next to treatment category records, 4. Of the records in the category of physical assessment and care, records in vital signs. placed first at 98.9 percent, followed by sleep at 76.2 percent, body weight at 74.7 percent, symptoms and signs at 69.3 percent, rest at 44.5 percent, hygiene at 39.7 percent, activities and participation at 16.9 percent, positions at 10.3 percent, level of consciousness at 9.8 percent and physiological dysfunction at 1.1 percent in that order. 5. Records in the category of psychological assessment and care averaged 3.2 percent, the lowest of the -three major categories. 6. Of the records in the category of psychological assessment and care, records on emotional responses ranked top at 10.5 percent, followed by self-concern at 2.1 percent, adjustment at 2.0 percent, family, occupational and social relations at 0.7 percent and preferences. and interest at 0.5 percent in that order. 7. Records in relation to the category of specific conditions were found in 9.1 percent of the total records. 8. Of the records in the category of specific conditions, consultation and transfer records, stood first at 25.0 percent, followed by precautionary measurements at 1.4 percent and isolation at 0.9 percent 9. A great difference in nursing record behavior was observed between the first week of hospitalization and the last week, with the first week's recordings much higher than the last week in the categories of treatment and specific conditions (p<0.01). and of physical assessment and care (p <0.05). 10. A big difference was also observed among the hospitals (p<0.01). 11. A big difference was also observed between the government-run hospitals and the private hospitals in the categories of physical assessment and care and specific conditions in the first week of hospitalization (P<0.05l), and in the category of psychological assessment and care in the last week (P<0.05). 12. Between the hospitals established with foreign aid and the other hospitals, the difference in nursing record behavior was significant only in the category of physical assessment and care both in the first week and the last week (P<0.01). 13. The average nursing record behavior in all care categories stood at 45.1 percent in the extent of its coverage in relation to the general expectations.