• Korean Journal of Crystallography
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• v.9 no.1
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• pp.11-14
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• 1998

The synthesis and characterization of [Cu(L)](NCS)2 (1) (L:2,5,9,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) are described. Crystal structure of 1 crystallizes in the monoclinic system, space group P21/a, a=7.622(2)Å, b=17.645(2) Å, c=8.223(3) Å, β=109.99(2)˚ Z=2. Least-squares refinement of 1 led to a R(Rw) factor of 0.087 (0.158) for 1535 observed reflections of F0>40(F0). The complex 1 has a square planar geometry with average Cu-N (secondary amines) bond distance of 2.030(4)Å. The axially disposed thiocyanate anions are not coordinated with Cu-N distances of 2.842(7) Å.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.6
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• pp.493-503
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• 2018

The present study is a conceptual replication of O'Grady, Lee, and Choo's (2003) earlier study designed to investigate two hypotheses (linear distance hypothesis vs. structural distance hypothesis) in relation to L2 Korean learners' processing of Korean subject and object relative clauses (RCs) in a scholarly attempt to explicate Keenan and Comrie's (1977) Noun Phrase Accessibility Hierarchy (NPAH). In addition, the current study is intended to explore any potential role of working memory capacity (WMC) in the processing of Korean subject and/or object RCs. Chinese-speaking learners of Korean taking a language course offered at a local university in Korea participated in this experimental study. Among those recruited, only 23 learners completed the experimental tasks appropriately according to the specific instructions provided on each task, and thus, subsequent statistical analyses were conducted on their data. Fifteen Korean NSs were also recruited for the control group. Two experimental tasks were administerd to the participants: one picture selection task containing the same test items used in O'Grady et al.'s study to measure their processing of subject-object RCs and an operation span (OSPAN) task to measure their WMC. Somewhat differently from O'Grady et al.'s findings, the participating Chinese learners of Korean performed significantly better on object RCs than on subject RCs, seemingly lending support to the linear distance hypothesis. Further analyses, however, suggested that the results in favor of, or relative ease of processing, object relative clauses were due, most likely, to the learners' excessive use of the canonical sentence strategy, which also led to nonsignificant correlations between WMC and learner performance on the picture selection task.

• Journal of Korean Neurosurgical Society
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• v.63 no.5
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• pp.614-622
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• 2020

Objective : The method of approach during transforaminal endoscopic lumbar discectomy (TELD) has been the subject of repeated study. However, the ideal entry point during TELD has not been studied in detail. Therefore, this study investigated the ideal entry point for avoiding complications using computed tomography (CT) scans obtained from patients in the prone position. Methods : Using CT scans obtained from patients in the prone position, we checked for retroperitoneal or visceral violations and measured the angles of approach with five conventional approach lines drawn on axial CT scans at each disc space level (L2-3, L3-4, and L4-5). We also determined the ideal entry point distance and approach angles for avoiding retroperitoneal or visceral violations. Correlation analysis was performed to identify the patient characteristics related to the ideal entry point properties. Results : We found that the far lateral approach at the L2-3 level resulted in high rates of visceral violation. However, rates of visceral violation at the L3-4 and L4-5 levels were remarkably low or absent. The ideal angles of approach decreased moving caudally along the spine, and the ideal entry point distances increased moving caudally along the spine. Weight, body mass index (BMI), and the depth of the posterior vertebral line from the skin were positively associated with the distance of the ideal entry point from the midline. Conclusion : We reviewed the risk of the extreme lateral approach by analyzing rates of retroperitoneal and visceral violations during well-known methods of approach. We suggested an ideal entry point at each level of the lumbar spine and found a positive correlation between the distance of the entry point to the midline and patient characteristics such as BMI, weight, and the depth of the posterior vertebral line from the skin.

• The Journal of Advanced Prosthodontics
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• v.16 no.4
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• pp.212-220
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• 2024

PURPOSE. This cone-beam computed tomography (CBCT) study aimed to analyze the anatomical characteristics of alveolar bone at mandibular first molar (MFM) and their implications for immediate implant placement surgery. MATERIALS AND METHODS. 100 patients with 140 MFMs were reviewed retrospectively. We first performed a 3D reconstruction of the patient's CBCT data to determine a reference plane with ideal implant placement and orientation. The following parameters of MFM region were analyzed: mesial-distal socket size (MDSS), buccal-lingual socket size (BL-SS), root furcation fornix to inferior alveolar nerve (IAN) distance (RF-I), interradicular bone thickness (IRB), mesial/distal root apex to the IAN distance (MRA-I/DRA-I), thickness of the buccal/lingual bone of the mesial root (MR-B/MR-L), thickness of the buccal/lingual bone of the distal root (DR-B/DR-L). RESULTS. The MD-SS of MFM was 8.74 ± 0.76 mm, and the BLSS was 8.26 ± 0.72 mm. The MR-B, DR-B was 1.01 ± 0.40 mm and 1.14 ± 0.50 mm, and the difference was statistically significant (P = .001). The values of the MR-L, DR-L were 2.71 ± 0.78 mm and 3.09 ± 0.73 mm, and the difference was also statistically significant (P < .001). The mean distance of RF-I was 15.68 ± 2.13 mm, and the MRA-I was 7.06 ± 2.22 mm, which was greater than that of DRA-I (6.48 ± 2.30 mm, P < .001). The IRB at 2 mm, 4 mm apical from the furcation fornix, and at apex level was 2.81 ± 0.50 mm, 3.30 ± 0.62 mm, and 4.44 ± 1.02 mm, respectively. CONCLUSION. There is relatively sufficient bone mass in interradicular bone in height, but an adequate width is lacking for the bone between the mesial and distal root after the extraction of the MFM for immediate implantation. The thickness of the MFM buccal bone is relative thin, especially for the mesial root.

• Journal of Welding and Joining
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• v.4 no.3
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• pp.50-57
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• 1986

In this study, the experiments were earried out for the purpose of the clarifying the optimum metal arc spraying conditions, such as spraying distance, wire feed speed, arc current, etc, by using the stainless steel wire ER 308L. Main results obtained are as follows: 1. Optimum spraying distance is closely related to the equilibrium temperature of base material in back surface. 2. The size fused metal particles is increased according to the temperature of fused metal. 3. The maximum adhesion strength of coatings is obtained under the optimum spraying conditions of which the temperature of fundamental is maximum.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.80-84
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• 1991

We cloned and expressed hepatitis B viral core antigen (HBcAg) gene in E. coli using $P_{L}$ promoter system. For optimal expression of the gene, we undertook the studies on the effects of the distance between Shine-Dalgarno (SD) sequence and start codon, copy number of repressor gene, induction temperature, and the stability of the core antigen. The results demonstrated that the induction at 37.deg.C was more efficient than at 42.deg.C, and the 11 base pairs (bp) distance between SD sequence and start codon of HBcAg gene was more efficient than the 15 bp distance in E. coli. The copy number of cI857 repressor gene did not influence on the expression of HBcAg, and the expression level of HBcAg in mutant type (low protease activity) and wild type strains was almost the same. The produced core antigen appeared to be HBcAg not HBeAg judged by two different radioimmunoassat (RIA) kits. This result suggested that the antigen was stable in E. coli.i.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.4
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• pp.267-274
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• 2001

A prototype experiment on the anchovy boat seine was carried out in the southern sea of korea to analyze the vertical opening and the underwater geometry. The vertical opening and the underwater geometry of the prototype net were determined by distance of Minilog position with the combinations of the distance between paired boats and the towing speed. The results osbtained can be summarized as follows; 1. Vertical opening of the protype net was gradually lowered according to the increase of the distance between paired beats and the towing speed. 2. Vertical opening of Wing net, Inside wing net, Square, Fore bag net, Flapper and After bag net of the prototype net according to the distance between paired boats were varied in the range of 8.4~9.0, 15.7~17.4, 12.9~17.9, 13.6~19.0, 8.3~8.4, 11.1~14.7m respectively, varied in the range of 12~16, 22~24, 27~38, 59~83, 92~93, 41~54% of the normal opening respectively. 3. Vertical opening of Wing net, In side wing net, Square, Fore bag net, Flapper and After bag net of the prototype net according to the towing speed were varied in the range of 7.7~10.5, 19.6~21.6, 12.2~16.9, 15.4~17.1, 8.0~8.2, 13.7~14.7m respectively, varied in the range of 14~19, 27~30, 32~36, 67~74, 89~91, 51~54% of the normal opening respectively. 4. Prototype net was appeared apparent the pocket shape, because Wing net and Inside wing net was opened 20% of the normal opening. 5. Working depth of the prototype net was gradually shallow according to the increase of the distance between paired boats and the towing speed.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.1-5
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• 1998

The complex[Cu(L)I2, 2H2O(1) (L:3,14-Dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18, 07.12]docosane) has been prepared and structurally characterized. The complex (1) crystallizes in the triclinic system, space group P1, a=8.400(1)Å, b=8.986(3) Å, c=9.156(1) Å, α=82.42(1)˚, β=73.61(1)˚ λ=81.04(2)˚, Z=1, R for 1926 observed reflections of [F0>40(F0)], measured at 288K, was 0.042. The tetracoordination around Cu atom of complex(1) is square plane and the average bond distance of Cu-N is 2.029 (11) Å. Both six-membered chelate rings adopts a chair conformation and the five-membered ring are gauche with the sec-NH centers having the RRSS configuration.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.201-206
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• 2018

The purpose of this study is to estimate a proper Domain Watch between anchored vessels in order to propose a method for the efficient management of VTS(Vessel Traffic Service) of the N-anchorage in Busan harbor, which is the largest port in Korea. For this purpose, we proposed the calculation method of Domain Watch and investigated the ship length(L), the distance between anchored vessels ($D_{ij}$), the domain radius(R), and the domain radius vs L(R/L) during the peak time of the vessels in the latest usage of anchorage. As a result of technical analysis for the surveyed data, the minimum R/L for securing the safety distance between anchored vessels was selected based on 2.85 corresponding to the 70th percentile of the total data. This result was applied to the N-anchorage of Busan and compared with the 'Guidelines of Port and Harbor Design(2014)', and we have confirmed that it is reasonable to set the Domain radius with the minimum 2.85L or more in VTS. This study considers the safety management of anchorage for VTS. This study could contribute to the safety of vessels using anchorage and the safety management plan of VTS when it is applied to other ports in operation such as it was in Busan.

• ALGAE
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• v.37 no.1
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• pp.15-32
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• 2022

Inspecting herbaria collections of Laurencia rigida highlighted frequent misidentifications between L. rigida and L. heteroclada f. decussata, two poorly studied taxa from Australia. Recent collections of DNA material, including from topotype material, allowed for re-examination of these two taxa using molecular techniques. Detailed morphological and molecular analyses based on two markers (rbcL and COI-5P) strongly supported these two taxa as being distinct from each other and requiring nomenclatural changes. Comprehensive morphological analyses highlighted features useful for accurate identifications. Interestingly, L. rigida was found to belong to the genus Palisada with evidence from both the morphology and molecular data. Therefore, this study proposed recognizing L. rigida as Palisada rigida comb. nov. Molecular data for L. heteroclada f. decussata on the other hand supported its separation from L. heteroclada, with too great a molecular distance to be considered a variety. Morphological characters that best separated P. rigida from L. decussata included seven characters; number of pericentral cells per vegetative axial segment, the presence of secondary pit connections, the presence of lenticular thickenings, tetrasporangia alignment, the presence of corps en cerise, holdfast morphology, and overall plant shape. Morphologically, L. heteroclada f. decussata was also separated from L. heteroclada, particularly by the following characteristics; ultimate branchlets morphologies, lower order branch lengths, primary axis and holdfast morphologies. Therefore, it was proposed that L. heteroclada f. decussata is recognized at a species level as L. decussata comb. et stat. nov.