• Journal of Korea Society of Industrial Information Systems
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• v.28 no.1
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• pp.35-48
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• 2023

In this study, we introduced the development status and the government policy of the Chinese automobile industry under the rapidly changing global economic environment. We conducted a consumer trend survey on automobile purchases by consumers in China. Despite the Chinese government's strong national emission control policy and stricter standards for manufacturing and selling internal combustion engine vehicles, 59.6% of respondents saying they would choose an internal combustion engine vehicle when purchasing a vehicle in the future for various reasons. It was confirmed that there is a significant gap between government policies and consumer perceptions. In addition, we have discovered the recent declining trend of automobile sales in China, and used the monthly sales volume from January 2010 to December 2020 as training set, and the sales volume from January 2021 to November 2022 as a test set. We proposed and evaluated a time-series model for predicting future automobile demand in China. Then, we showed the monthly sales forecast for 2023 when each model was applied.

• Imaging Science in Dentistry
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• v.52 no.3
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• pp.303-308
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• 2022

Purpose: This technical report aims to describe and detail the use of micro-computed tomography for a reliable evaluation of the bulk-fill composite/tooth interface. Materials and Methods: Bulk-fill composite restorations in tooth cavities were scanned using micro-computed tomography to obtain qualitatively and quantitatively valuable information. Two-dimensional information was processed using specific algorithms, and ultimately a 3-dimensional (3D) specimen reconstruction was generated. The 3D rendering allowed the visualization of voids inside bulk-fill composite materials and provided quantitative measurements. The 3D analysis software VG Studio MAX was used to perform image analysis and assess gap formation within the tooth-restoration interface. In particular, to evaluate internal adaptation, the Defect Analysis addon module of VG Studio Max was used. Results: The data, obtained with the processing software, highlighted the presence and the shape of gaps in different colours, representing the volume of porosity within a chromatic scale in which each colour quantitatively represents a well-defined volume. Conclusion: Micro-computed tomography makes it possible to obtain several quantitative parameters, providing fundamental information on defect shape and complexity. However, this technique has the limit of not discriminating materials without radiopacity and with low or no filler content, such as dental adhesives, and hence, they are difficult to visualise through software reconstruction.

• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.174-183
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• 2022

Acoustic radiation from a submerged elastic shell with an internal fluid surrounded by the bubble layer is studied with the modal theory. An omni-directional point source located on the center of the internal fluid is used as acoustic noise source. The unknown coefficients of modal solutions are solved using the interface conditions between media. To preserve the stability of the modal solution over wide frequency ranges, the scaled technique of modal solution is used. The bubble layer is modeled with four kinds of bubble distribution; uni-modal distribution, uniform distribution, normal distribution, and power-law distribution, based on the effective medium theory of Commander and Prosperetti. For each bubble distribution, the insertion losses are mainly calculated for the frequency. In addition, the numerical simulations are performed depending in the bubble void fraction, the material property of elastic shell, and the gap between the bubble layer and the elastic shell.

• Asia Marketing Journal
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• v.16 no.2
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• pp.59-75
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• 2014

Although previous works have established that mood can considerably influence consumer behavior (Vohs et al. 2007), they provided inconsistent results (Cohen et al. 2008). In particular, previous works only examined the willingness of consumers to regulate their mood and implicitly assumed that consumers have the control to regulate their mood states. Thus, this research intends to fill the current gap in the extant literatures by investigating whether consumer locus of control (CLOC) can act as a moderator for mood effects on consumers' likelihood to purchase. In an experiment, participants' CLOC was initially measured. Afterwards, they watched different video clips to induce different mood states. Finally, participants rated their likelihood to purchase after seeing an advertisement. The results suggest that, in the positive mood, CLOC tendencies do not impact consumers' likelihood to purchase. However, in the negative mood, internal CLOC consumers show a higher likelihood to purchase than external CLOC consumers. This phenomenon occurs because consumers with high internal CLOC tendencies have the motivation to regulate their negative mood. These findings extend the extant literatures in four aspects. First, this paper shows that the CLOC tendencies could influence consumers' motivation to regulate their negative mood. Second, this research examines the moderating effect of CLOC in the relationship between mood and consumers' likelihood to purchase. Third, the results add further evidence regarding the role of negative mood in the self-regulation process. Finally, this research also shows that mood can unconsciously influence consumer behavior. This paper provides two managerial implications. First, marketers should consider the mood states and consumers' control tendencies in creating advertisements. Second, firms in retail or service business should aim to evoke a positive mood on consumers so that their CLOC tendencies would not influence their behaviors.

• Restorative Dentistry and Endodontics
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• v.34 no.3
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• pp.177-183
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• 2009

The aim of this study was to evaluate the marginal and internal gaps in CEREC3 CAD/CAM inlays of three different preparation designs. CEREC3 Inlays of three different preparation designs (n=10) were fabricated according to Group I-conventional functional cusp capping/shoulder preparation, Group II-horizontal reduction of cusps and Group III-complete reduction of cusps/shoulder preparation. After cementation of inlays. the bucco-lingual cross section was performed through the center of tooth. Cross section images of 20 magnifications were obtained through the stereomicroscope. The gaps were measured using the Leica application suite software at each reference point. Statistical analysis was performed using one-way ANOVA and Tukey's test (${\alpha}<0.05$). The marginal gaps ranged from 80.0 to $97.8{\mu}m$ for Group I, 42.0 to $194.8{\mu}m$ for Group II, 51.0 to $80.2{\mu}m$ for Group III. The internal gaps ranged from 90.5 to $304.1{\mu}m$ for Group I, 80.0 to $274.8{\mu}m$ for Group II, 79.7 to $296.7{\mu}m$ for Group III. The gaps of each group were the smallest on the margin and the largest on the horizontal wall. For the CEREC3 CAD/CAM inlays, the simplified designs (groups II and III) did not demonstrate superior results compared to the traditional cusp capping design (group I).

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.254-261
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• 2020

Purpose: The purpose of this study was to assess the marginal and internal fit of interim crowns fabricated by two different manufacturing method (subtractive manufacturing technology and additive manufacturing technology). Materials and Methods: Forty study models were fabricated with plasters by making an impression of a master model of the maxillary right first molar for ceramic crown. On each study model, interim crowns (n = 40) were fabricated using three types of 3D printers (Meg-printer 2; Megagen, Zenith U; Dentis, and Zenith D; Dentis) and one type milling machine (imes-icore 450i; imes-icore GmbH). The internal of the interim crowns were filled with silicon and fitted to the study model. Internal scan data was obtained using an intraoral scanner. The fit of interim crowns were evaluated in the margin, absolute margin, axial, cusp, and occlusal area by using the superimposition of 3D scan data (Geomagic control X; 3D Systems). The Kruskal-wallis test, Mann-Whitney U test and Bonferroni correction method were used to compare the results among groups (α = 0.05). Results: There was no significant difference in the absolute marginal discrepancy of the temporary crown manufactured by three 3D printers and one milling machine (P = 0.812). There was a significant difference between the milling machine and the 3D printer in the axial and occlusal area (P < 0.001). The temporary crown with the milling machine showed smaller axial gap and higher occlusal gap than 3D printer. Conclusion: Since the marginal fit of the temporary crown produced by three types of 3D printers were all with in clinically acceptable range (< 120 ㎛), it can be sufficiently used for the fabrication of the temporary crown.

• Tuberculosis and Respiratory Diseases
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• v.59 no.2
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• pp.151-156
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• 2005

Background : Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in hospital-acquired infection, and is prevalent in intensive care units (ICU). The MRSA colonization rates of the nares and throat were examined in both the ICU and general ward. This study was performed to investigate the MRSA rate and necessity for MRSA screening cultures in patients admitted to ICU. Methods : Between June and September 2004, those patients admitted to both the medical ICU and general ward participated in this study. Bacterial cultures were performed on swabs of the nares and throat taken within 24 hours of admission. Clinical data were also collected. Results : One hundred and twenty one patients and 84 patients, admitted to the medical ICU and medical general ward, respectively, were investigated. The numbers of nasal MRSA colonization in the ICU and general ward were 3 (2.5%) and 3 (3.6%), respectively. There were 2 (1.7%) cases of throat MRSA colonization in the ICU, but none in the general ward. The MRSA colonization rates of the nares and throat were no different between the ICU and general ward. There were no significant differences in the previous admission, operation history and admission route between the ICU and general ward groups. Conclusion : The MRSA colonization rates of the nares and throat were 3.3 and 3.6% in the ICU and the general ward, respectively. The MRSA screening test does not appear to be required in all patients admitted to the ICU, but further studies, including high-risk patients, are recommended.

• Journal of Gastric Cancer
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• v.5 no.4 s.20
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• pp.222-227
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• 2005

Purpose: There are several reports suggested the usefulness of serum tumor markers, AFP, CEA and CA19-9 as prognostic factors or indicators for recurrence in gastric cancer. This clinical study was peformed to evaluate positive rate of tumor markers according to site of recurrence in gastric cancer. Materials and Methods: From the database of patients who underwent radical gastrectomy for gastric cancer between January 1999 and January 2004, 52 patients who showed recurrence were included in this retrospective study. Serum levels of tumor markers were measured at the time of preoperative diagnosis of the gastric cancer and at the time of postoperative recurrence during follow up, respectively. Results: The overall positivity of tumor markers at the time of recurrence was found to be significantly higher than that of prior to surgery in the recurred group for the single test as well as the combination tests. For the peritoneum, the most common recurrent site, the positivity of CA19-9 was higher at the time of recurrence. And the significant positivity of CEA at the time of recurrence was detected in the liver cases. Conclusion: Having a preoperative positive tumor marker may identify the patient as having an increased chance of a recurrence. Although tumor markers continue to have limited diagnostic significance in gastric cancer, CA19-9 may be useful as a predictor for peritoneal recurrence of the gastric cancer, and CEA for recurrence to liver.

• Tuberculosis and Respiratory Diseases
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• v.50 no.3
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• pp.334-342
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• 2001

Background : RpoB gene mutations have been found in about 96-98% of rifampicin (RMP)-resistant Mycobacterium tuberculosis. Recent reports confirm that the in laboratory settings a rpoB gene mutation can be used as a surrogate marker for multi-drug resistant tuberculosis. However, its usefulness in clinical applications has not been evaluated. This study was performed to confirm whether mutation analysis of the rpoB gene of M. tuberculosis is useful in clinical settings. Methods : The medical records of 33 patients in whom rpoB gene analysis was conducted using an INNOLiPA Rif. TB assay (LiPA) from June, 1998, to July, 2000, at the Asan Medical Center were retrospectively reviewed in 33 patients. The clinical characteristics in addition to the drug susceptibility and LiPA results were analyzed. The drug susceptibility test was considered as a gold standard method for M. tuberculosis susceptibility and these results were compared with those of the rpoB gene study and sequencing analysis. Sequencing analysis of the rpoB gene was done in cases where there was a discrepancy between the results of the drug susceptibility an d rpoB gene study. Results : The mean age and sex ratio was $42{\pm}18$, and 24:9 (M:F), respectively. There were 19 RMP susceptible (58%) and 14 RMP-resistant cases (42%) according to the rpoB gene study. The mean time from the request to reporting the results of the rpoB gene study was $5.2{\pm}2.6$ days. The mean gap from reporting the rpoB gene study to reporting the susceptibility was $56{\pm}35$ days. Twenty-eight cases (85%) showed identical results compared with the drug susceptibility results, whereas five cases (15%) showed contradictory results. When compared with the sequencing analysis, of the five cases that showed contradictory results, two had LiP A analysis errors and the remaining three were identical to the sequencing results. The rpoB gene study was of assistance in choosing the appropriate drugs in 28 cases (85%). Conclusions : An rpoB gene study using an LiP A assay was useful in rapidly diagnosing RMP-resistant tuberculosis, which enabled a proper choice of the appropriate drugs in clinical practices. However, an LiPA assay always should be performed in conjunction with microscopy, culture, and susceptibility tests.

• Korean Medical Education Review
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• v.14 no.2
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• pp.95-101
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• 2012

As North Korea passed from the Devotion (Jeongseong) movement to the black market (Jangmadang) system, the medical service system in that country was effectively destroyed. North Korean physicians who have successfully defected to South Korea (North Korean defector physicians, NKDPs) have experienced socio-economic hardships on their way to becoming incorporated into the South Korean medical system due to different medico- social cultures, different (English-based) medical terminology, and the clinical knowledge gap between North and South Korea. Since 2009, we have operated programs at the Seoul Medical Center to help NKDPs prepare for the South Korean medical licensing examination. These programs consist of clinical education at the medical center, personal mentoring, arrangement of educational programs at the medical college, mock tests at the consortium, and administrative aid. Looking forward, we hope to achieve the following: 1) More systematic support plans are needed involving medical education experts, field physicians, and experts on reunification. 2) An evaluation of defector physicians' current medical knowledge may provide information about the areas where supplementary education is most needed and the standards for certificating licenses. 3) In the short term, a customized glossary should be developed to assist defector physicians prepare for the examination. 4) To secure internships and residencies is the most important issue for further sustained training of NKDP physicians to become good clinicians after certification. Hopefully, this short report on the current ongoing educational course will lead to more extensive discussion.