• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.543-548
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• 1997

The first permanent molar takes important place in the occlusion. Malposition of the lower first molar is frequently due to mesial migration, which is occurred by early exfoliation of the second deciduous molar or proximal caries of deciduous teeth. Above things happen without any consideration of space maintainer, prompt measures for space regaining have to be started. Especially in the case with early loss of the second deciduous molar, it has been said that there is no suitable appliance for maintaining the space before the eruption of the permanent first molar. In distalizing the upper first molar, headgears have been routinely used, which its result was definitely depended on cooperation of the patients. Nowadays, appliances such as pendulum appliances, K-loop, magnets, which can be used without cooperation of the patients, are introduced. Jones Jig, one of the molar distalizing appliances, was used on the patients who visited department of pediatric dentistry in Seoul National University Dental Hospital complaining of no eruption space for the lower second bicuspid. Either removable splint or lingal arch was used as the anchorage. Jones Jig was favorably used in the lower molar, where vestibule is shallow, and this is a case report on the satisfactory result thereof.

• Nuclear Engineering and Technology
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• v.45 no.7
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• pp.921-928
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• 2013

A future nuclear energy system is being developed at Korea Atomic Energy Research Institute (KAERI), the system involves a Sodium Fast Reactor (SFR) linked with the pyro-process. The pyro-process produces a source material to fabricate a SFR fuel rod. Therefore, an isotopic fissile content assay is very important for fuel rod safety and SFR economics. A new technology for an analysis of isotopic fissile content has been proposed using a lead slowing down spectrometer (LSDS). The new technology has several features for a fissile analysis from spent fuel: direct isotopic fissile assay, no background interference, and no requirement from burnup history information. Several calculations were done on the designed spectrometer geometry: detection sensitivity, neutron energy spectrum analysis, neutron fission characteristics, self shielding analysis, and neutron production mechanism. The spectrum was well organized even at low neutron energy and the threshold fission chamber was a proper choice to get prompt fast fission neutrons. The characteristic fission signature was obtained in slowing down neutron energy from each fissile isotope. Another application of LSDS is for an optimum design of the spent fuel storage, maximization of the burnup credit and provision of the burnup code correction factor. Additionally, an isotopic fissile content assay will contribute to an increase in transparency and credibility for the utilization of spent fuel nuclear material, as internationally demanded.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.317-328
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• 2021

This study aims to determine the factors that affect dividends initiation by initial public offering firms in Malaysia. The ownership structure is examined from a corporate governance theoretical perspective in order to evaluate the impacts of managerial, institutional, and family ownership on the dividend's initiation decision of IPO firms. This study employs a quantitative pooled cross-section of 372 Malaysian IPO companies active during the period of 2002-2013. The number of firms that went public each year varies, thus the pooled cross-section data takes place in this case rather than the panel data. The logistic model was employed to test the proposed hypotheses. The results revealed that the presence of institutional investors in the ownership structure make it more likely for IPO firms to initiate dividends. On the contrary, the presence of a family ownership structure in IPO companies as the controlling shareholder makes these companies less probable to initiate dividends. Managerial ownership was found to have no effect on the decision of initiating dividends by IPO firms. The findings of this study suggest that the existence of institutional and family ownerships are agency cost mitigators, as these ownership types could prompt IPOs firms to initiate dividends to overcome the agency conflicts.

• Journal of Trauma and Injury
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• v.36 no.3
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• pp.269-275
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• 2023

A Morel-Lavallée lesion results from a degloving injury between the muscle fascia and the subcutaneous layer. It is most commonly found in the trochanteric area but can occur at other sites. The treatment of the condition varies according to the medical circumstances, as well as the size and chronicity of the condition. A case of large (18×6 and 10×5 cm) bilateral posttraumatic Morel-Lavallée lesions with no underlying bone fracture is presented; the case occurred in a 49-year-old male patient 4 weeks posttrauma. Ultrasound scans showed bilateral large collections of anechoic fluid, which were aspirated under ultrasound guidance and further managed by compression bandages. There were no further complications. The objective of this case report is to present this unique and educational case, as well as to provide an overview of the pathophysiology, diagnosis, and management of Morel-Lavallée lesions. We conclude by discussing the importance of having a high index of suspicion to ensure early detection and prompt treatment of such lesions to avoid complications.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.1
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• pp.49-60
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• 2005

The Back Bone of gearing portion between Core Network System which is used in wire and wireless system is No.7 Protocol. ISUP( ISDN User Part), INAP handling in Intelligent Network and MAP gearing method for linking each Network Element System in mobile network have use of No.7 signaling. Therefore, it is require for system to detect the problem - operating problem occurs in Core Network which use No.7 signaling or the existing problem that is not recognized - in shortest time. This paper study out analyzing and measuring system for No.7 protocol and analyzing out system whether out of order or not. It can abstract No.7 Signaling Message and analyze system performance and report it. This system is connected in system No.7 HW Module which is in charge of No.7 Signaling. It is not offer Emulator function and Simulation function for any scenario but offer monitoring No.7 signaling. This system perform the function about No.7 MTP, ISUP, INAP and MAP and is offered several wire and wireless network Operator. It can detect and correct SW system, HW system and operating system problem. From now on, this system may offer the function about A-interface which is gearing between BSC and MSC, so it will perform to analyze generally and prompt effective operating for Core Network system.

• Journal of Korean Neurosurgical Society
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• v.60 no.6
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• pp.667-675
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• 2017

Objective : Total resection without consecutive postoperative whole brain radiation therapy is indicated for patients with a single or two sites of brain metastasis, with close follow-up by serial magnetic resonance imaging (MRI). In this study, we explored the effectiveness, usefulness, and safety of this follow-up regimen. Methods : From January 2006 to December 2015, a total of 109 patients (76 males, 33 females) underwent tumor resection as the first treatment for brain metastases (97 patients with single metastases, 12 with two metastases). The mean age was 59.8 years (range 27-80). The location of the 121 tumors in the 109 patients was supratentorial (n=98) and in the cerebellum (n=23). The origin of the primary cancers was lung (n=45), breast (n=17), gastrointestinal tract (n=18), hepatobiliary system (n=8), kidney (n=7), others (n=11), and unknown origin (n=3). The 121 tumors were totally resected. Follow-up involved regular clinical and MRI assessments. Recurrence-free survival (RFS) and overall survival (OS) after tumor resection were analyzed by Kaplan-Meier methods based on clinical prognostic factors. Results : During the follow-up, MRI scans were done for 85 patients (78%) with 97 tumors. Fifty-six of the 97 tumors showed no recurrence without adjuvant local treatment, representing a numerical tumor recurrence-free rate of 57.7%. Mean and median RFS was 13.6 and 5.3 months, respectively. Kaplan-Meier analysis revealed the cerebellar location of the tumor as the only statistically significant prognostic factor related to RFS (p=0.020). Mean and median OS was 15.2 and 8.1 months, respectively. There were no significant prognostic factors related to OS. The survival rate at one year was 8.2% (9 of 109). Conclusion : With close and regular clinical and image follow-up, initial postoperative observation without prompt postoperative radiation therapy can be applied in patients of brain metastasi(e)s when both the tumor(s) are completely resected.

• Restorative Dentistry and Endodontics
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• v.29 no.2
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• pp.177-184
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• 2004

Objectives : This study investigated the hypothesis that increasing light-curing time would leave the oxygen-inhibited layer (OIL) of the adhesive thinner, and in turn, result in lower shear bond strength (SBS) than those obtained by the routine curing procedures. Methods：120 human extracted posterior teeth were randomly divided into three groups for bonding with three adhesives：All Bond 2/sup (R)/, One Step/sup (R)/, and Adper Prompt/sup (R)/. They were subsequently divided into four subgourps with different light-curing time (10, 20, 30 and 60s). The assigned adhesives were applied on superficial occlusal dentin according to the manufacturer's instructions and cured with one of the four curing times. Composite resin cylinder, 2.35㎜ in diameter, were built on the cured adhesive and light-cured for 40s. SBS were measured after 24h from the bonding using a universal testing machine (crosshead speed 1.0 ㎜/min). The relative thickness of the OIL and the degree of conversion (DC) were determined from the adhesive on a slide glass using FT-NIR in an absorbance mode. Data were analysed with One-way ANOVA and Duncan's multiple test (p〈0.05), Results：With increasing cure time, although there were no significant difference in th SBS of One-step and Adper Prompt (p〉0.05), those of All Bond 2 decreased significantly (p〈0.05). The relative thicknesses of the OIL on each adhesive were not affected by the cure time (p〉0.05). Although the DC of All-Bond 2 were statistically not different with increasing cure time (p〉0.05), those of One-Step and Adper Prompt showed an increasing trends with increasing cure time (p〈0.05). Conclusions：Increasing light-curing time did not affect on the relative thickness of the OIL of the adhesives, and in turn, on the SBS to dentin.

• Restorative Dentistry and Endodontics
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• v.29 no.1
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• pp.66-72
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• 2004

All-in-one adhesives were recently developed for reducing the technique sensitivity and chair time, but lots of concerns were made on bondability, longevity, and microleakage. The object of this study was to evaluate microleakage and marginal quality of all-in-one adhesives using electrochemical method and SEM analysis quantitatively. After making Class V cavities, they were bulk filled with Heliomolar(#A1 after surface treatment with three adhesives: Adper Prompt (Group A), One up bond F (Group O), Xeno III (Group X) Electrical conductivity (microamphere, ${\mu}A$) was checked two times: before and after cavity filling. Percentage of leaky margin was estimated from SEM image (${\times}1,000$). The data were statistically analysed: ANOVA and Paired T test for electrical conductivity, Kruskal-Wallis and Mann-Whitney test for marginal quality, Spearman s rho test for checking of relationships between 2 methods. The result were as follows: 1. There was no difference in microleakage between adhesive systems and every specimen showed some of microleakage after filling. 2. Microleakage was reduced about 70% with composite resin filling. 3. Marginal quality was the best in group A. decreasing among groups in the following order: group O, followed by group X. There were significant differences between group A and group X (p=0.015), and between group 0 and group X (p=0.019). 4. There was no relationship between the microleakage measured by electrochemical method and marginal quality measured by SEM analysis. Within the results of this study, there was no difference in microleakage among groups by electrical conductivity. However, significant difference in marginal quality was seen among groups. It was believed that these dissimilar results might be induced because of their own characteristics. Analysis of microleakage needs various methods for accuracy.

• Archives of Craniofacial Surgery
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• v.22 no.4
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• pp.177-182
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• 2021

Background: Although prompt surgery after an orbital fracture is preferable, the actual timing of surgery in real-world settings varies. Therefore, this study investigated the outcomes of implant surgery for inferior orbital wall fractures by comparing three groups according to the time interval between the injury and surgery. Methods: A retrospective review was conducted of patients' medical charts and initial computed tomography images from 2009 to 2020. The time to treatment was chosen by patients or their guardians based on the patients' comorbidities and the physician's explanation. The patients were divided into three groups according to the time of surgery (group 1: 3-7 days, group 2: 8-14 days, group 3: 15 or more days). Data were collected on age, the time interval until surgery, the dimensions of the defect, the operation time, the follow-up period, and the postoperative paresthesia score (ranging from 0 to 10). The outcomes were evaluated using a 4-point scale: 4=good (no complications), 3=fair (no subjective symptoms), 2=poor (remaining paresthesia), and 1=very poor (strabismus and/or enophthalmos). Results: The study included 85 patients with unilateral fractures who underwent surgery from 3 to 93 days after injury. The overall score distribution of the surgical outcomes was as follows: good=63, fair=7, poor=6, and very poor=9. The three groups showed no significant differences in the transverse dimension of the injury (p=0.110) or the anteroposterior dimension (p=0.144). In groups 1, 2, and 3, the postoperative outcome scores were 3.84±0.37, 3.63±0.87, and 2.93±1.33 (p=0.083), and the percentage of patients with good outcomes was 84%, 81.25%, and 57.14%, respectively. Conclusion: Performing surgery using an artificial implant within 2 weeks of the injury showed better outcomes and fewer postoperative complications than when treatment was delayed.

• Journal of Mechanical Science and Technology
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• v.16 no.7
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• pp.1009-1018
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• 2002

The Representative Interactive Flamelet (RIF) concept has been applied to numerically simulate the combustion processes and pollutant formation in the direct injection diesel engine. Due to the ability for interactively describing the transient behaviors of local flame structures with CFD solver, the RIF concept has the capabilities to predict the auto-ignition and subsequent flame propagation in the diesel engine combustion chamber as well as to effectively account for the detailed mechanisms of soot formation, NOx formation including thermal NO path, prompt and nitrous 70x formation, and reburning process. Special emphasis is given to the turbulent combustion model which properly accounts for vaporization effects on the mixture fraction fluctuations and the pdf model. The results of numerical modeling using the RIF concept are compared with experimental data and with numerical results of the commonly applied procedure which the low-temperature and high-temperature oxidation processes are represented by the Shell ignition model and the eddy dissipation model, respectively. Numerical results indicate that the RIF approach including the vaporization effect on turbulent spray combustion process successfully predicts the ignition delay time and location as well as the pollutant formation.