• Geomechanics and Engineering
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• 제10권6호
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• pp.737-755
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• 2016

The load transfer depth of a ground anchor is the minimum length required to transfer the initial prestressing to the grout column through the bonded part. A thorough understanding of the mechanism of load transfer as well as accurate prediction of the load transfer depth are essential for designing an anchorage that has an adequate factor of safety and satisfies implicit economic criteria. In the current research, experimental and numerical studies were conducted to investigate the load transfer mechanism of ground anchors based on a series of laboratory and field load tests. Optical FBG sensors embedded in the central king cable of a seven-wire strand were successfully employed to monitor the changes in tensile force and its distribution along the tendons. Moreover, results from laboratory and in-situ pullout tests were compared with those from equivalent case studies simulated using the finite difference method in the FLAC 3D program. All the results obtained from the two proposed methods were remarkably consistent with respect to the load increments. They were similar not only in trend but also in magnitude and showed more consistency at higher pullout loading stages, especially the final loading stage. Furthermore, the estimated load transfer depth demonstrated a pronounced dependency on the surrounding ground condition, being shorter in hard ground conditions and longer in weaker ones. Finally, considering the safety factor and cost-effective design, the required bonded length of a ground anchor was formulated in terms of the load transfer depth.

• Journal of architectural history
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• 제27권2호
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• pp.51-62
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• 2018

This study examines the site and erection of the Government Complex Seoul which was a project attempted to assemble dispersed government buildings in a certain place. The study focuses on the fact that the project is situated between the 1960s' making of capital Seoul and Seoul urban planning, and the way how the project achieved symbolism in capital Seoul. The project, one of the 1960s' Major Government Buildings, led both plan of capital Seoul and transforming city Seoul. The 1960s' Major Government Building Plan had identical drive with the 1950's Major Government Building Plan, however the 1960s' had additional layer: Seoul urban planning. After restoration of the Capital building, Sejongro the capital street was planned to the site arranging government offices. The Government Complex Seoul was set to be a modern building on a site with historical context according to the plan. Because of the site, the Government Complex Seoul was constructed in aware of other buildings that represented a competitive high-rise atmosphere in the late 1960s, including the Capital building nearby. PAE International's plan was completed through a series of design modification, and it boasted a vertical aspect, unlike the horizontal-looking plan that was already won after the design competition. The Government Complex Seoul tried to acquire the symbolism in the central space of the capital Seoul and high-rised city Seoul. "The new construction method" was a requirement to achieve the height.

• Korean Journal of Materials Research
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• 제17권5호
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• pp.250-255
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• 2007

The alloying effects on the electronic structures of Zinc are investigated using the relativistic $DV-X{\alpha}molecular$ orbital method in order to obtain useful information for alloy design. A new parameter which is the d obital energy level(Md) and the bonder order(Bo) of alloying elements in Zinc was introduced and used for prediction of the mechanical properties. The Md correlated with the atomic radius and the electronegativity of elements. The Bo is a measure of the strength of the covalent bond between M and X atoms. First-principles calculations of electronic structures were performed with a series of models composed of a MZn18 cluster and the electronic states were calculated by the discrete variational- $X{\alpha}method$ by using the program code SCAT. The central Zinc atom(M) in the cluster was replaced by various alloying elements. In this study energy level structures of pure Zinc and alloyed Zinc were calculated. From calculated results of energy level structures in MZn18 cluster, We found Md and Bo values for various elements of Zn. In this work, Md and Bo values correlated to the tensile strength for the Zn. These results will give some guide to design of zinc based alloys for high temperature applications and it is possible the excellent alloys design.

• Polymer(Korea)
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• 제29권1호
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• pp.59-63
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• 2005

Kinetic study of a reaction between poly(caprolactone diol) and aliphatic isocyanate was investigated by FTIR spectroscopy. The reaction rate was obtained from analyzing the absorbance change of NCO peak (2265 $cm^{-1}$) in series IR spectra. In the results, the overall reaction between PCL and isocyanate conformed to the simple second-order law, and the rate constant increases with increasing reaction temperature. The activation energies obtained from the evaluation of kinetic data were 25.4∼30.9 kJ/mol for hexamethylene diisocyanate and 16.8∼22.1 kJ/mol for cyclohexylmethane diisocyanate, respectively.

• The Plant Pathology Journal
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• 제26권4호
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• pp.306-312
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• 2010

The pathotypes of Cercospora beticola, causal agent of sugar beet leaf spot disease, were identified by application of pathogenicity test using 100 isolates obtained from the provinces with intensive sugar beet cultivation. For the identification of pathotypes, five sugar beet cultivars were used each with different resistance factors. Cultivar reactions were determined by inoculation of cultivars with the isolates under controlled conditions and measuring disease severity on the $15^{th}$ day according to the 1-9 KWS Scale. Based on the reactions of the five cultivars, a total of 15 pathotypes were detected. All employed sugar beet cultivars were resistant to Pathotype no:1 comprising most of the isolates. Genetic diversity of the causal agent was characterized by AFLP reaction. The products acquired at the end of AFLP reaction were detected by means of Beckman CEQ 8800 DNA Capillary Series Analysis and the results obtained were evaluated according to the similarity index UPGMA. For the genetic analysis of C. beticola isolates, 9874 polymorphic fragments of sizes between 100 and 500 bp were analysed which were generated by nine primers. The dendrogram derived from AFLP analysis depicted the existence of five different subgroups. The polymorphism rate among isolates was 91.13% and the dendrogram distribution of the pathotypes obtained by pathogenicity indicated that pathotypes were not discriminated and did not compose any groups.

• Economic and Environmental Geology
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• 제10권3호
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• pp.107-117
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• 1977

The Charyong batholith extends northeasterly from the west coast to the west of Wonju in the central parts of Korean Penninsula. The batholith is separated by the metamorphic complex into the northern and the southern granites. and is believed to intrude during the Daebo orogeny of early Jurassic to early Cretaceous age. It constitutes a sort of anticlinorium and the metamorphic complex can be regarded as a huge roof pendant. The modal analysis indicates that the Charyong batholith belongs to a series of adamellite-granodiorte-to-nalite. The oxidation property happened during a magmatic segregation reveals that the batholith shows in general orogenic assimilation trend. The granites of early to middle Jurassic age show orogenic assimilation trend, whereas those of late Jurassic to early Cretaceous age post orogenic noassimilation trend. The fracture system of the whole region is two folds: the fractures having attitute of $N25{\sim}40^{\circ}E$ and $70^{\circ}SE$ are regarded as tension fractures, and those of NS, and 50E to vertical and $N50^{\circ}E$ and $80^{\circ}E$ to vertical as shear fractures. All these facts suggest definitely that the Charyong batholith is the syntectonic intrusives during the Daebo orogeny. The mineral deposits in the area studied are gold-silver deposits in majority which was named by O,J.Kim(1970) as the Chonan metallogenic province. They are sulfides baring quartz veins which were emplaced along the tension and shear fractures originated by the Daebo orogeny.

• Archives of Plastic Surgery
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• 제48권5호
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• pp.528-533
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• 2021

Bladder acontractility affects several thousand patients in the United States, but the available therapies are limited. Latissimus dorsi detrusor myoplasty (LDDM) is a therapeutic option that allows patients with bladder acontractility to void voluntarily. Our goal was to conduct a systematic review of the literature to determine whether LDDM is a better option than clean intermittent catheterization (CIC) (standard treatment) in patients with bladder acontractility. On January 17, 2020, we conducted a systematic review of the PubMed/MEDLINE, Cochrane Clinical Answers, Cochrane Central Register of Controlled Trials, Embase, and ClinicalTrials.gov databases, without time frame limitations, to identify articles on the use of LDDM for bladder acontractility. Of 75 potential articles, 4 fulfilled the eligibility criteria. The use of LDDM to treat patients with bladder acontractility was reported in four case series by the same group in Europe. Fifty-eight patients were included, and no comparison groups were included. The most common cause of bladder acontractility was spinal cord injury (n=36). The mean (±standard deviation) operative time was 536 (±22) minutes, postoperative length of hospital stay ranged from 10 to 13 days, and follow-up ranged from 9 to 68 months. Most patients had complete response, were able to void voluntarily, and had post-void residual volume less than 100 mL. Although promising outcomes have been obtained, evidence is still weak regarding whether LDDM is better than CIC to avoid impairment of the urinary tract among patients with bladder acontractility. Further prospective studies with control groups are necessary.

• Journal of Ocean Engineering and Technology
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• 제33권3호
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• pp.259-271
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• 2019

It is important to obtain reasonable predictions of the extent of the damage during maritime accidents such as ship collisions and groundings. Many fracture models based on different mechanical backgrounds have been proposed and can be used to estimate the extent of damage involving ductile fracture. The goal of this study was to compare the damage extents provided by some selected fracture models. Instead of performing a new series of material constant calibration tests, the fracture test results for the ship building steel EH36 obtained by Park et al. (2019) were used which included specimens with different geometries such as central hole, pure shear, and notched tensile specimens. The test results were compared with seven ductile fracture surfaces: Johnson-Cook, Cockcroft-Latham-Oh, Bai-Wierzbicki, Modified Mohr-Coulomb, Lou-Huh, Maximum shear stress, and Hosford-Coulomb. The linear damage accumulation law was applied to consider the effect of the loading path on each fracture surface. The Swift-Voce combined constitutive model was used to accurately define the flow stress in a large strain region. The reliability of these simulations was verified by the good agreement between the axial tension force elongation relations captured from the tests and simulations without fracture assignment. The material constants corresponding to each fracture surface were calibrated using an optimization technique with the minimized object function of the residual sum of errors between the simulated and predicted stress triaxiality and load angle parameter values to fracture initiation. The reliabilities of the calibrated material constants of B-W, MMC, L-H, and HC were the best, whereas there was a high residual sum of errors in the case of the MMS, C-L-O, and J-C models. The most accurate fracture predictions for the fracture specimens were made by the B-W, MMC, L-H, and HC models.

• Geomechanics and Engineering
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• 제17권3호
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• pp.253-259
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• 2019

Concrete-to-concrete bedding planes (CCBP) are observed from time to time due to the multistep hardening process of the concrete materials. In this paper, a series of direct/cyclic shear tests are performed on CCBP under static and dynamic normal load conditions to study the frictional behavior effect by the shear velocities, normal impact frequencies, horizontal shear frequencies, normal impact force amplitudes, horizontal shear displacement amplitudes and normal load levels. According to the experimental results, apparent friction coefficient k ($k=F_{Shear}/F_{Normal}$) shows different patterns under static and dynamic load conditions at the stable shear stage. k is nearly constant in direct shear tests under constant normal load conditions (DCNL), while it is cyclically changing with nearly constant peak value and valley value for the direct shear tests under dynamic normal load conditions (DDNL), where k increases with decreasing normal force and decreases with increasing normal force. Shear velocity has little influence on peak values of k for the DCNL tests, but increasing shear velocity leads to increasing valley values of k for DDNL tests. It is also found that, the valley values of k ascend with decreasing impact normal force amplitude in DDNL tests. The changing pattern of k for the cyclic shear tests under constant and dynamic normal load conditions (CCNL and CDNL tests) are similar, but the peak value of k is smaller in CDNL tests than that in CCNL tests. Normal load levels, shear displacement amplitudes, vertical impact frequencies, horizontal shear frequencies and normal impact force amplitudes have little influence on the changing pattern of k for the cyclic shear tests. The tests of this study provide useful data in understanding the frictional behavior of the CCBP under distinct loadings, and these findings are very important for analyzing the stability of the jointed geotechnical structures under complicated in situ stress conditions.

• Journal of Haehwa Medicine
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• 제28권1호
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• pp.1-12
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• 2019

Objectives : The aim of this study is to review clinical studies of facial palsy sequelae treatment Methods : We used search engines such as PUBMED, OASIS, RISS. We limited sequelae as the cases after three months from the onset. We excluded the studies including operational treatments. We considered papers pubulished only after year 2000. Results : The kinds of treatments were acupunture treatment, physical therapy, Botulinum toxin, and steroids and antiviral agent. Four studies about acupuncture treatment were searched. Two were case studies and the other two were case series studies. Six studies about physical therapy were searched and they were devided into three according to their specific methods - neuromuscular training and biofeedback, electrical stimulation, and facial exercises. We reviewed three studies about Botulinum toxin and 3 studies about combined therapy. Conclusions : Evidence level of the acupuncture studies was not high. Neuromuscular retraining and biofeedback therapies were shown to be effective especially to synkinesis. Mime therapy, one of the facial exercise has significant effect. Electrical stimulation is thought to activate the plasticity of central nerve system. Botulimum Toxin has effective temporary treatment. Steroid therapy increases recovery rate and reduces sequelae.