• Restorative Dentistry and Endodontics
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• v.39 no.1
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• pp.7-11
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• 2014

Objectives: The aim of this study was to compare the dimensional standard of several nickel-titanium (Ni-Ti) rotary files and verify the size conformity. Materials and Methods: ProFile (Dentsply Maillefer), RaCe (FKG Dentaire), and TF file (SybronEndo) #25 with a 0.04 and 0.06 taper were investigated, with 10 in each group for a total of 60 files. Digital images of Ni-Ti files were captured under light microscope (SZX16, Olympus) at $32{\times}$. Taper and diameter at $D_1$ to $D_{16}$ of each files were calculated digitally with AnalySIS TS Materials (OLYMPUS Soft Imaging Solutions). Differences in taper, the diameter of each level ($D_1$ to $D_{16}$) at 1 mm interval from (ANSI/ADA) specification No. 101 were statistically analyzed using one-way ANOVA and Scheffe's post-hoc test at 95% confidence level. Results: TF was the only group not conform to the nominal taper in both tapers (p < 0.05). All groups except 0.06 taper ProFile showed significant difference from the nominal diameter (p < 0.05). Conclusions: Actual size of Ni-Ti file, especially TF, was different from the manufacturer's statements.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.32-38
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• 2020

Based on the cases of fire and explosion accident in the chemical reactor, thr problems of preventive measures installed in the chemical reactor were analyzed. The chemical reactors produce a variety of chemicals and install rupture disk to relieve the pressure that rises sharply in the event of a runaway reaction. In order to maintain the function of the rupture disk, the emissions was allowed to be discharged into the atmosphere, resulting in fire and explosion accidents. As a way to improve this, safety instrumented system based on the safety integrity level(SIL3) was applied as a preventive measures for chemical reactor. Two emergency shur-off valves are installed in series on pipe dropping raw materials for chemical reactor so that the supply of raw materials can be cut off even if only one of the two emergency shut-off valves is operated during the runaway reaction. The automatic on/off valve is installed in parallel in the supply pipe of the reaction inhibitor so that the reaction inhibitor can be injected even if only one valve is opened at the time of the runaway reaction.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.103-107
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• 2012

This study was performed to design a modified Y-View as an imaging method for the Y-View in supine position for patients who requires Y-View imaging for the diagnosis of shoulder impingement syndrome but having trouble for the positioning of patients complaining of shoulder pain. On the result of comparative analysis of the images obtained by changing the lateral-medio degree of X-ray tube into $35^{\circ}$, $40^{\circ}$, and $45^{\circ}$ while patient is in supine position, $40^{\circ}$ of X-ray tube in lateral-medio direction produced the most valuable image for the diagnosis by best describing the shapes of acromion, clavicle space, and coracoacromial arch. Therefore, patients who have difficulty in Y-View position to obtain Y-View image, modified Y-View can be applied as a useful alternative method. By this study, various applications not only in shoulder impingement syndrome but also in diverse omarthralgia diseases are expected.

• YAKHAK HOEJI
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• v.44 no.2
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• pp.182-188
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• 2000

High soy consumption leading to high exposures of soy isoflavones has been associated with a reduced risk of cancers at many sites. As part of a study focusing on the chemopreventive mechanisms, we have investigated the modulating effects of daidzein and genistein, a prominent and more bioavailable isoflavone in soy foods, on murine immune function. Daidzein (50 mg/kg) or genistein (50 mg/kg) was administered p.o. once a day for 7 days in BALB/c mice. Daidzein decreased the mitogen-stimulated proliferation of murine splenocyte, but genistein increased it. Daidzein stimulated the secretion of interleukin-4, but inhibited the secretion of ${\gamma}$-interferon, interleukin-2 and tumor necrosis factor-$\alpha$. Genistein stimulated the secretion of ${\gamma}$-interferon, interleukin-2 and tumor necrosis factor-$\alpha$, but inhibited the secretion of interleukin-4. Daidzein and geiustein inhibited the production of nitric oxide and enhanced the phagocytic activity in peritoneal macrophage. These results suggest that cancer preventive effects of daidzein is partly concerned with the secretion of $T_{H}$2 cells cytokine and the activation of macrophage phagocytosis, and genistein is partly concerned with the secretion of $T_{H}$l cells cytokine, tumor necrosis factor-$\alpha$ and the activation of macrophage phagocytosis.sis.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.455-461
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• 2018

Background: Surgical-site, multimodal drug injection has recently evolved to be a safe and useful method for multimodal pain management even in patients with musculoskeletal trauma. Methods: Fifty consecutive patients who underwent plating for mid-shaft and distal clavicular fractures were included in the study. To evaluate whether surgical-site injections (SIs) have pain management benefits, the patients were divided into two groups (SI and no-SI groups). The injection was administered between the deep and superficial tissues prior to wound closure. The mixture of anesthetics consisted of epinephrine hydrochloride (HCL), morphine sulfate, ropivacaine HCL, and normal saline. The visual analogue scale (VAS) pain scores were measured at 6-hour intervals until postoperative hour (POH) 72; stress biomarkers (dehydroepiandrosterone sulfate [DHEA-S], insulin, and fibrinogen) were measured preoperatively and at POH 24, 48, and 72. In patients who wanted further pain control or had a VAS pain score of 7 points until POH 72, 75 mg of intravenous tramadol was administered, and the intravenous tramadol requirements were also recorded. Other medications were not used for pain management. Results: The SI group showed significantly lower VAS pain scores until POH 24, except for POH 18. Tramadol requirement was significantly lower in the SI group until POH 24, except for POH 12 and 18. The mean DHEA-S level significantly decreased in the no-SI group ($74.2{\pm}47.0{\mu}g/dL$) at POH 72 compared to that in the SI group ($110.1{\pm}87.1{\mu}g/dL$; p = 0.046). There was no significant difference in the insulin and fibrinogen levels between the groups. The correlation values between all the biomarkers and VAS pain scores were not significantly different between the two groups (p > 0.05). Conclusions: After internal fixation of the clavicular fracture, the surgical-site, multimodal drug injection effectively relieved pain on the day of the surgery without any complications. Therefore, we believe that SI is a safe and effective method for pain management after internal fixation of a clavicular fracture.

• Journal of the Korea Society of Computer and Information
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• v.11 no.3
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• pp.31-39
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• 2006

This paper presents a novel approach to real-time recognition of 3D environment and objects for various applications such as intelligent robots, intelligent vehicles, intelligent buildings,..etc. First, we establish the three fundamental principles that humans use for recognizing and interacting with the environment. These principles have led to the development of an integrated approach to real-time 3D recognition and modeling, as follows: 1) It starts with a rapid but approximate characterization of the geometric configuration of workspace by identifying global plane features. 2) It quickly recognizes known objects in environment and replaces them by their models in database based on 3D registration. 3) It models the geometric details the geometric details on the fly adaptively to the need of the given task based on a multi-resolution octree representation. SIFT features with their 3D position data, referred to here as stereo-sis SIFT, are used extensively, together with point clouds, for fast extraction of global plane features, for fast recognition of objects, for fast registration of scenes, as well as for overcoming incomplete and noisy nature of point clouds.

• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.790-799
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• 2018

UHD broadcasting based on ATSC 3.0 is being implemented in Korea, and discussion on mobile broadcasting based on ATSC 3.0 is underway. The ATSC 3.0 standard introduces internet protocol based standards in order to facilitate the implementation of conventional broadcasting services as well as broadcasting and communication convergence services interlocking with communication services. In this process, various requirements for the receiver have been derived, and factors to consider for developing the receiver product have also increased. ATSC 3.0 broadcasting is currently in the introduction stage of the service, and additional technology development and product implementation related to the receiver should proceed until the full-scale market is formed. In this regard, this paper describes the considerations for developing UHD receiver based on ATSC 3.0 and the test procedure for verifying developed receiver.

• Journal of the Korean Society of Safety
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• v.35 no.6
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• pp.78-84
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• 2020

The F&EI technique is one of the risk assessments with many advantages. It can save time and effort compared to quantitative risk assessment (QRA). By using the evaluation result of this technique, it is possible to check the effectiveness of the investment cost. In addition, a relative risk ranking can be created and used to establish the facility management cycle and to prioritize investment. However, evaluating the target process can be evaluated more than the actual risk since the LCCF, a loss prevention measure, is too limited. In addition, calculating premiums via this method can result in excessive premiums, making it difficult to evaluate the risk precisely. Therefore, new safety guard was added to the LCCF of the F&EI risk assessment with reference to HAZOP and LOPA techniques. Newly added LCCFs are Deflagration arrester, Check valve, SIS, and Vacuum beaker, etc. As a case study, F&EI risk assessment was performed on Acetone storage tank of a API (Active pharmaceutical ingredient) plant to compare actual MPPD. The estimated loss amount was 592,558$ for the existing technique and 563,571$ for the improved technique, which was reduced by about 5% compared to the previous one.This proved that a more precise evaluation is possible and that the efforts for safety at the workplace are reflected in the evaluation results.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.265-270
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• 2022

With the implementation of the fox restoration project, the number of foxes released into nature are increasing; therefore, in the future, foxes will be dispersed to other areas and will appear in human habitats. In this study, the habitat suitability index (HSI) of foxes was developed to predict and prepare for the effects. After extracting major environmental variables through literature research and GIS analysis, 5 suitability indices (SIs) were constructed. The forest physiognomy, slope, aspect, distance from water source, and distance from road are the main variables, and the arithmetic average value by giving twice the weight to the forest physiognomy is the HSI result. As a result of comparing with the data from the Natural Environment Survey, it is found that the fox coordinates have an average HSI value of 0.64, and the probability of appearance is high when it is 0.53 or higher. Using the results of this study, it is expected to be able to predict the distribution of foxes in advance, to use them as basic data for future restoration plans, or to identify the distribution of the species and the reduction plan in future environmental impact assessments.

• Nuclear Engineering and Technology
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• v.27 no.4
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• pp.518-531
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• 1995

A study has been Peformed to investigate the thermal margin increase by replacing the single-channel analysis model with a multichannel analysis model. h new critical heat flux(CHF) correlation, which is applicable to a 17$\times$17 Korean Fuel Assembly(KOFA)-loaded core, was developed on the basis of the local conditions predicted by the subchannel analysis code, TORC. The hot sub-channel analysis was carried out by using one-stage analysis methodology with a prescribed nodal layout of the core. The result of the analysis shooed that more than 5％ of the thermal margin can be recovered by introducing the TORC/KRB-1 system(multichannel analysis model) instead of the PUMA/ERB-2 system(single-channel anal)sis model). The thermal margin increase was attributed not only to the effect of the local thermal hydraulic conditions in the hot subchannel predicted by the code, but also to the effect of the characteristics of the CHF correlation.