• Geomechanics and Engineering
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• v.11 no.3
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• pp.439-455
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• 2016

This paper presented solutions of displacement and stress for a circular opening which is reinforced with grouted rock bolt. It satisfies the Mohr-Coulomb (M-C) or generalized Hoek-Brown (H-B) failure criterion, and exhibits elastic-brittle-plastic or strain-softening behavior. The numerical stepwise produce for strain-softening rock mass reinforced with grouted rock bolt was developed with non-associative flow rules and two segments piecewise linear functions related to a principle strain-dependent plastic parameter, to model the transition from peak to residual strength. Three models of the interaction mechanism between grouted rock bolt and surrounding rock proposed by Fahimifar and Soroush (2005) were adopted. Based on the axial symmetrical plane strain assumption, the theoretical solution of the displacement and stress were proposed for a circular tunnel excavated in elastic-brittle-plastic and strain-softening rock mass compatible with M-C or generalized H-B failure criterion, which is reinforced with grouted rock bolt. It showed that Fahimifar and Soroush's (2005) solution is a special case of the proposed solution for n = 0.5. Further, the proposed method is validated through example comparison calculated by MATLAB programming. Meanwhile, some particular examples for M-C or generalized H-B failure criterion have been conducted, and parametric studies were carried out to highlight the influence of different parameters (e.g., the very good, average and very poor rock mass). The results showed that, stress field in plastic region of surrounding rock with considering the supporting effectiveness of the grouted rock bolt is more than that without considering the effectiveness of the grouted rock bolt, and the convergence and plastic radius are reduced.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6547-6555
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• 2014

This study attempted to verify what motivates fans to follow college sports teams' social media and identify the motivational factors that can best predict fans' social media consumption. Confirmatory Factor Analysis (CFA) indicated that previously identified seven motives for online consumption, i.e., information, diversion, socialization, pass-time, fanship, team support, and technical knowledge, are compatible with the use of college sports teams' social media. In addition, a results of multiple regression found diversion, socialization, fanship, team support, and technical knowledge to significantly predict the level of social media consumption while information and pass-time did not significantly affect social media consumption. In particular, socialization had the greatest influence on social media consumption.

• Journal of the Optical Society of Korea
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• v.19 no.1
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• pp.55-62
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• 2015

In this study we demonstrate ultrahigh-resolution spectral domain optical coherence tomography (UHR SD-OCT) with a linear-wavenumber (k) spectrometer, to accelerate signal processing and to display two-dimensional (2-D) images in real time. First, we performed a numerical simulation to find the optimal parameters for the linear-k spectrometer to achieve ultrahigh axial resolution, such as the number of grooves in a grating, the material for a dispersive prism, and the rotational angle between the grating and the dispersive prism. We found that a grating with 1200 grooves and an F2 equilateral prism at a rotational angle of $26.07^{\circ}$, in combination with a lens of focal length 85.1 mm, are suitable for UHR SD-OCT with the imaging depth range (limited by spectrometer resolution) set at 2.0 mm. As guided by the simulation results, we constructed the linear-k spectrometer needed to implement a UHR SD-OCT. The actual imaging depth range was measured to be approximately 2.1 mm, and axial resolution of $3.8{\mu}m$ in air was achieved, corresponding to $2.8{\mu}m$ in tissue (n = 1.35). The sensitivity was -91 dB with -10 dB roll-off at 1.5 mm depth. We demonstrated a 128.2 fps acquisition rate for OCT images with 800 lines/frame, by taking advantage of NVIDIA's compute unified device architecture (CUDA) technology, which allowed for real-time signal processing compatible with the speed of the spectrometer's data acquisition.

• Journal of IKEEE
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• v.11 no.1 s.20
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• pp.69-76
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• 2007

This paper presents the design of LVDS (Low-Voltage-Differential-Signaling) transmitter for Gb/s-per-pin operation. The proposed LVDS transmitter is designed using BiCMOS technology, which can be compatible with CMOS technology. To reduce chip area and enhance the robustness of LVDS transmitter, the MOS switches of transmitter are replaced with lateral bipolar transistor. The common emitter current gain($\beta$) of designed bipolar transistor is 20 and the cell size of LVDS transmitter is $0.01mm^2$. Also the proposed LVDS driver is operated at 1.8V and the maximum data rate is 2.8Gb/s approximately In addition, a novel ESD protection circuit is designed to protect the ESD phenomenon. This structure has low latch-up phenomenon by using turn on/off character of P-channel MOSFET and low triggering voltage by N-channel MOSFET in the SCR structure. The triggering voltage and holding voltage are simulated to 2.2V, 1.1V respectively.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.69-75
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• 2015

PURPOSE. To compare the shear bond strength of various veneering materials to grade II commercially pure titanium (CP-Ti). MATERIALS AND METHODS. Thirty specimens of CP-Ti disc with 9 mm diameter and 10 mm height were divided into three experimental groups. Each group was bonded to heat-polymerized acrylic resin (Lucitone 199), porcelain (Triceram), and indirect composite (Sinfony) with 7 mm diameter and 2 mm height. For the control group (n=10), Lucitone 199 were applied on type IV gold alloy castings. All samples were thermocycled for 5000 cycles in $5-55^{\circ}C$ water. The maximum shear bond strength (MPa) was measured with a Universal Testing Machine. After the shear bond strength test, the failure mode was assessed with an optic microscope and a scanning electron microscope. Statistical analysis was carried out with a Kruskal-Wallis Test and Mann-Whitney Test. RESULTS. The mean shear bond strength and standard deviations for experimental groups were as follows: Ti-Lucitone 199 ($12.11{\pm}4.44$ MPa); Ti-Triceram ($11.09{\pm}1.66$ MPa); Ti-Sinfony ($4.32{\pm}0.64$ MPa). All of these experimental groups showed lower shear bond strength than the control group ($16.14{\pm}1.89$ MPa). However, there was no statistically significant difference between the Ti-Lucitone 199 group and the control group, and the Ti-Lucitone 199 group and the Ti-Triceram group. Most of the failure patterns in all experimental groups were adhesive failures. CONCLUSION. The shear bond strength of veneering materials such as heat-polymerized acrylic resin, porcelain, and indirect composite to CP-Ti was compatible to that of heatpolymerized acrylic resin to cast gold alloy.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.26
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• pp.111-117
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• 1992

In the stock marketing. investor needs speedy and accurate decision making for the investment. A stock exchange index provides the important index of the early of 1993 in Korea using Fuzzy Delphi Method(F. D. M) which is widely used to a mid and long range forecasting in decision making problem. In the Fuzzy Delphi method, considerably qualified experts an first requested to give their opinion seperately and without intercommunication. The forecasting data of experts consist of Triangular Fuzzy Number (T.F.N) which represents the pessimistic, moderate, and optimistic forecast of a stock exchange index. A statistical analysis and dissemblance index are then made of these subject data. These new information are then transmitted to the experts once again, and the process of reestimation is continued until the process converges to a reasonable stable forecast of stock exchange index. The goal of this research is to forecast the stock exchange index using F.D.M. in which subjective data of experts are transformed into quasi -objective data index by some statistical analysis and fuzzy operations. (a) A long range forecasting problem must be considered as an uncertain but not random problem. The direct use of fuzzy numbers and fuzzy methods seems to be more compatible and well suited. (b) The experts use their individual competency and subjectivity and this is the very reason why we propose the use of fuzzy concepts. (c) If you ask an expert the following question: Consider the forecasting of the price index of stocks in the near future. This experts wi11 certainly be more comfortable giving an answer to this question using three types of values: the maximum value, the proper value, and the minimum value rather than an answer in terms of the probability.

• Food Science and Preservation
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• v.13 no.4
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• pp.495-500
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• 2006

In order to investigate whether antioxidant biomaterials inhibits IL-4 and/or IL-13 expression in vitro and in vivo, we carried out antioxidant assays by enzyme or cell-based assays with Helianthus annuus extract. Antioxidant assays include DPPH, FRAP, hydroxyl radical assays. Helianthus annuus extract exhibited SOD scavenging activity, and had different patterns by each solvent extracted reaction. DW extract inhibited oxidative stress by $H_2O_2$ that induced apoptosis. We measured $CD4^+$ cell and IL-/13 cytokine expression in a classical mouse animal model. The result show that Helianthus annuus extract showed strung inhibition of immune response in the lung. These result suggest that Helianthus annuus extract can reduce inflammation induced by n mouse asthma model.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.804-810
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• 1999

There is a possibility that carvone, a monoterpene from spearmint (Mentha spicata), could induce the bph degradative pathway and genes in Alcaligenes eutrophus H850, which is a known Gram-negative PCB degrader with a broad substrate specificity that was thoroughly investigated with Arthrobacter sp. BIB, a Gram-positive PCB degrader. The strains BIB and H850 were unable to utilize and grow on the plant terpene [(R)-(-)-carvone] (50ppm) to be recognized as a sole carbon source. Nevertheless, the carvone did induce 2,3-dihydroxybiphenyl 1,2-dioxygenase (encoded by bphC) in the strain B lB, as observed by a resting cell assay that monitors accumulation of a yellow meta ring fission product from 4,4'-dichlorobiphenyl (DCBp). The monoterpene, however, did not appear to induce the meta cleavage pathway in the strain H850. Instead, an assumption was made that the strain might be using an alternative pathway, probably the ortho-cleavage pathway. A reverse transcription (RT)-PCR system, utilizing primers designed from a conserved region of the bphC gene of Arthrobacter sp. M5, was employed to verify the occurrence of the alternative pathway. A successful amplification (182bp) of mRNA transcribed from the N-terminal region of the bphC gene was accomplished in H850 cells induced by carvone (50ppm) as well as in biphenyl-growth cells. It is, therefore, likely that H850 possesses a specific PCB degradation pathway and hence a different substrate specificity compared with B1B. This study will contribute to an elucidation of the dynamic aspects of PCB bioremediation in terms of roles played by PCB degraders and plant terpenes as natural inducer substrates that are ubiquitous and environmentally compatible.

• Restorative Dentistry and Endodontics
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• v.43 no.1
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• pp.2.1-2.10
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• 2018

Objectives: To determine the effect of size and insertion depth of irrigation needle on the amount of apical extruded debris and the amount of penetration depth of sealer using a confocal laser scanning microscope (CLSM). Materials and Methods: Twenty maxillary premolars were assigned to 2 groups (n = 10), according to the size of needle tip, 28 G or 30 G. Buccal roots of samples were irrigated with respective needle type inserted 1 mm short of the working length (WL), while palatal roots were irrigated with respective needle type inserted 3 mm short of the WL. Prepared teeth were removed from the pre-weighed Eppendorf tubes. Canals were filled with F3 gutta-percha cone and rhodamine B dye-labeled AH 26 sealer. Teeth were transversally sectioned at 1 and 3 mm levels from the apex and observed under a CLSM. Eppendorf tubes were incubated to evaporate the irrigant and were weighed again. The difference between pre- and post-weights was calculated, and statistical evaluation was performed. Results: Inserting needles closer to the apex and using needles with wider diameters were associated with significantly more debris extrusion (p < 0.05). The position of needles and level of sections had statistically significant effects on sealer penetration depth (p < 0.05 for both). Conclusions: Following preparation, inserting narrower needles compatible with the final apical diameter of the prepared root canal at 3 mm short of WL during final irrigation might prevent debris extrusion and improve sealer penetration in the apical third.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.113-116
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• 2010

The initial presentation of distant metastases in patients with papillary thyroid carcinoma is quite rare. Most distant metastases are solid nodular lesions. A 67-year-old man who complained of severe dyspnea underwent surgery due to a large mediastinal cystic mass compressing the trachea and great vessels. Pathologically, the cystic mass was a metastatic thyroid papillary carcinoma. The thyroid evaluations were compatible with a well differentiated thyroid carcinoma. An occult thyroid carcinoma presenting as a large mediastinal cystic lesion is extremely rare.