• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.5
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• pp.456-463
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• 2015

Nowadays, small quantity batch production, which is so-called a flexible manufacturing system, is a major trend in the modern factory automation industry. The demands for new transportation system are increased gradually, with which multiple passive carriers carrying materials and semi-products are precisely and individually controlled along a single closed rail. Thus, a new type of permanent magnet linear synchronous motor (PMLSM), which consists of state coils on a single rail and PM movers as many as carriers, is proposed in this paper. The rail can be segmented as modules with pairs of coils and a current amplifier, which makes the transportation system simple; therefore, the rail can be easily extended and repaired. A design method of the new PMLSM with a single carrier is proposed, which can be thought as a new version of PMLSM, a coil-segmented coreless PMLSM (CS-CLPMLSM). Experimental setup for it is made, and propulsion results show that with the help of a new effective coil selection and switching algorithms, the conventional current-based vector control is sufficient to fulfill the position and velocity control of the new PMLSM. The proposed PMLSM is expected to fulfill seamless servo-control of multiple carriers also in process line, such as a new generation of flat panel display manufacturing line.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.2
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• pp.5-22
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• 2017

The purpose of this study is to analyze the teaching and learning strategies included in the inquiry tasks of elementary moral textbooks with multiple intelligences (M.I), and to propose educational information services of teacher librarians. It was found that the tasks were mainly designed by the linguistic intelligence, logical & mathematical intelligence and spatial intelligence. In terms of the information literacy process, linguistic intelligence and spatial intelligence are mainly applied to the analysis-understanding stage. Logical & mathematical intelligence is applied to the stage of comprehensive-application and linguistic intelligence is applied to expression-delivery step. In order to cultivate the insufficient M.I in inquiry activities, teacher librarians should improve room and teaching materials of their school library and provide workbooks using the graphic organizer after analyzing the linkage of the inquiry tasks between the subjects.

• Investigative and Clinical Urology
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• v.59 no.6
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• pp.371-375
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• 2018

Purpose: To compare patients with sepsis due to obstructive urolithiasis (Sep-OU) and underwent drainage by percutaneous nephrostomy (PCN) or a double-J (DJ)-ureteral stent and to identify predictive risk factors of DJ stent failure in these patients. Materials and Methods: We reviewed our records from January 2013 to July 2018 and identified 286 adult patients with Sep-OU out of which 36 had bilateral involvement, thus total 322 renal units were studied. Urologic residents in training carried out both ureteral stenting and PCN tube placement. Demographic data and stone characteristics were recorded along with Charlson comorbidity index. For predicting risk factors of DJ stent failure, those variables that had a p-value <0.1 in univariate analysis were combined in a multinomial regression analysis model. Results: The patients with PCN placement were significantly older than those with DJ stent placement (p=0.001) and also had significant number of units with multiple calculi (p=0.018). PCN was also placed more frequently in those patients with a upper ureteric calculi (p<0.05). On multinomial regression analysis multiple calculi (p=0.014; odds ratio [OR], 4.878; 95% confidence interval [CI], 1.377-17.276) and larger calculi size (p=0.040; OR, 0.974; 95% CI, 0.950-0.999) were the significant predictors of DJ stent failure. Conclusions: In patients with sepsis from obstructive urolithiasis due to larger and multiple calculi a PCN placement might be better suited although this data requires further prospective randomized studies to be extrapolated.

• Urogenital Tract Infection
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• v.13 no.3
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• pp.58-65
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• 2018

Purpose: This study aimed to investigate the relationship between uropathogens of infants with febrile urinary tract infection (UTI) and vesicoureteral reflux (VUR). Materials and Methods: We analyzed 308 infants hospitalized for febrile UTI between January 2010 and December 2015, and assessed the voiding cystourethrography (VCUG). The medical records, including clinical symptoms, laboratory findings, urinalysis, urine culture tests, ultrasound (US), dimercaptosuccinic acid scan, and VCUG, were retrospectively obtained. The incidences of VUR and high-grade VURs (III, IV, and V) were analyzed in 4 groups categorized by uropathogens and renal US findings. Results: The mean age of 308 infants was $3.29{\pm}2.18months$. The male-to-female ratio was 3.46:1. In urine culture tests, 267 infants (86.69%) showed single bacterial uropathogen; Escherichia coli in 241 infants (78.25%) and non-E. coli uropathogens in 26 infants (8.44%). Multiple distinctive microorganisms were identified as causative uropathogens in 41 infants (13.31%). Abnormal findings of US and VCUG were identified in 216 and 64 patients, respectively. In 308 infants, the incidences of VUR and high-grade VUR were not different among the 4 groups. In 239 male infants, the incidences of high-grade VUR were higher in patients with non-E. coli single or multiple uropathogen and with abnormal US findings (p=0.042). Conclusions: In male infants with non-E. coli uropathogen or multiple uropathogens and with abnormal US findings at febrile UTI, there was an increased chance of finding high-grade VURs on subsequent VCUG tests.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.1-8
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• 2022

This study examined whether the integrated education social studies textbooks developed for students with disabilities were properly implemented in terms of universal design for learning. For analysis, "Teaching and learning materials for inclusive education of students with disabilities: grade 3~6 social studies textbooks", which were instructional adaptation, were selected for students with disabilities who are unable to learn the contents of general textbooks for the 3rd to 6th grade of the elementary school social course in the 2015 revised curriculum. The social curriculum grades are composed of 20 units, including general public, geography and history. The content analysis standard was based on detailed items of 9 definitions according to the 3 principles of UDL presented in CAST (2018). Overall, the aspect of providing multiple means of action and expression was the most frequently observed, followed by providing multiple means of representation and providing multiple means of engagement. Special education teachers and textbook developers can use these results as a resource for designing curricula and lessons for students with disabilities in the inclusive classroom.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.267-278
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• 2009

The purpose of this study was to examine parents' perceptions towards, and the importance and performance levels of, foodservices in child-care centers and to suggest ways to increase foodservice quality and promote efficient operations in the future. A questionnaire survey was provided to 540 parents and the return rates 82%. The survey period was from June 20 to July 27,2007. The collected data were statistically analyzed with the SAS package program using descriptive statistical analysis, t-tests, ANOVA, Duncan's multiple comparisons, factor analysis, and multiple regression analysis. The results were as follows: The parents perceived that foodservice operations promoted their children's health and helped them form desirable dietary habits. The parents also had a high level of perception toward the need for foodservice, earning greater than 4.5 points out of 5 points. Their perceptions of foodservice quality were examined by four dimensions of importance and performance levels. While the parents gave 4 points or greater of 5 points to most quality attributes of importance level, they gave 4 points of less out of 5 points to most quality attributes of performance level. As for the importance and performance levels of the quality dimensions of meal service, the parents regarded sanitation as the most important dimension. IPA showed that 'organic food materials' was included as a 'focus here' area. The overall satisfaction level for foodservice was 3.59 out of 5 points. A higher level of satisfaction was shown when a dietitian was present as well as in public childcare centers. According to multiple regression analysis, 53.51% of the variance in the respondents' overall satisfaction scores was explained by factors such as food, sanitation, environment, and foodservice effects.

• Advances in nano research
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• v.15 no.5
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• pp.467-484
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• 2023

Despite the significant features of fiber-reinforced cementitious composites (FRCCs), including better mechanical, fractural, and durability performance, their high content of cement has restricted their use in the construction industry. Although ground granulated blast furnace slag (GGBFS) is considered the main supplementary cementitious material, its slow pozzolanic reaction stands against its application. The addition of nano-sized mineral modifiers, including nano-silica (NS), is an alternative to address the drawbacks of using GGBFS. The main object of this empirical and numerical research is to examine the effect of NS on the strain-hardening behavior of cementitious composites; ten mixes were designed, and five levels of NS were considered. This study proposes a new method, using a four-point bending test to assess the use of nano-silica (NS) on the flexural behavior, first cracking strength, fracture energy, and micromechanical parameters including interfacial friction bond strength and maximum bridging stress. Digital image correlation (DIC) was used for monitoring the initiation and propagation of the cracks. In addition, to attain a deep comprehension of fiber/matrix interaction, scanning electron microscope (SEM) analysis was used. It was discovered that using nano-silica (NS) in cementitious materials results in an enhancement in the matrix toughness, which prevents multiple cracking and, therefore, strain-hardening. In addition, adding NS enhanced the interfacial transition zone between matrix and fiber, leading to a higher interfacial friction bond strength, which helps multiple cracking in the composite due to the hydrophobic nature of polypropylene (PP) fibers. The findings of this research provide insight into finding the optimum percent of NS in which both ductility and high tensile strength of the composites would be satisfied. As a concluding remark, a new criterion is proposed, showing that the optimum value of nano-silica is 2%. The findings and proposed method of this study can facilitate the design and utilization of green cementitious composites in structures.

• Restorative Dentistry and Endodontics
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• v.48 no.3
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• pp.31.1-31.11
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• 2023

Objectives: This retrospective cohort study examined the incidence of interappointment emergencies during multiple-visit molar root canal treatments conducted by undergraduate students. Treatments performed without the use of intracanal medicament were compared to treatments that incorporated calcium hydroxide as an intracanal medicament. Materials and Methods: Interappointment emergencies, defined as instances of pain or swelling that required the patient to make an unscheduled follow-up visit, were recorded for up to 2 months after the intervention. To avoid the influence of obturation on the observed incidence of emergency visits, only unscheduled visits occurring between the start and end of the root canal treatment were included. Results: Of the 719 patients included in this study, 77 (10.7%) were recorded as experiencing interappointment emergencies. Of these emergencies, 62% occurred within 2 weeks following the most recent intervention. In the group of patients who did not receive intracanal medicament, the incidence of interappointment emergencies was 11.9% (46 of 385 patients). In comparison, this rate was 9.3% (31 of 334 patients) among those who received calcium hydroxide as an intracanal medicament (odds ratio, 1.33; 95% confidence interval, 0.82-2.15; p = 0.249). Conclusions: Interappointment emergencies may arise at any point during root canal treatment, but they most commonly occur within the first 2 weeks following intervention. The omission of intracanal medicament in multiple-visit molar root canal treatments, performed by undergraduate students, did not significantly increase the incidence of these emergencies.

• Journal of Gastric Cancer
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• v.24 no.2
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• pp.231-242
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• 2024

Purpose: This study aimed to investigate the recurrence patterns in patients who underwent curative surgery for gastric cancer (GC) and analyze their prognostic value for post-recurrence survival (PRS). Materials and Methods: We retrospectively reviewed the medical records of 204 patients who experienced GC recurrence following curative gastrectomy for GC at a single institution between January 2012 and December 2017. Specific recurrence patterns (lymph node, peritoneal, and hematogenous) and their multiplicity were analyzed as prognostic factors of PRS. Results: The median PRS of the 204 patients was 8.3 months (interquartile range [IQR]: 3.2-17.4). For patients with a single recurrence pattern (n=164), the difference in each recurrence pattern did not show a significant prognostic value for PRS (lymph node vs. peritoneal, P=0.343; peritoneal vs. hematogenous, P=0.660; lymph node vs. hematogenous, P=0.822). However, the patients with a single recurrence pattern had significantly longer PRS than those with multiple recurrence patterns (median PRS: 10.2 months [IQR: 3.7-18.7] vs. 3.9 months [IQR: 1.8-10.4]; P=0.037). In the multivariate analysis, multiple recurrence patterns emerged as independent prognostic factors for poor PRS (hazard ratio, 1.553; 95% confidence interval, 1.092-2.208; P=0.014) along with serosal invasion, recurrence within 1 year after gastrectomy, and the absence of post-recurrence chemotherapy. Conclusions: Regardless of the specific recurrence pattern, multiple recurrence patterns emerged as independent prognostic factors for poor PRS compared with a single recurrence pattern.

• Imaging Science in Dentistry
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• v.54 no.3
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• pp.221-231
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• 2024

Purpose: Multiple myeloma (MM) is a rare cancer that is typically managed with bisphosphonates to slow bone resorption and prevent skeletal complications. This study aimed to identify imaging patterns in MM patients receiving bisphosphonate therapy. Materials and Methods: This systematic review included studies investigating maxillomandibular bone alterations based on imaging examinations in MM patients treated with bisphosphonates. The selected studies were qualitatively assessed using the Critical Appraisal Tools from SUMARI. Results: Six studies, involving 669 MM patients, were included, with 447 receiving bisphosphonate treatment. The majority were treated with pamidronate, zoledronate, or a combination of both. Seventy patients developed medication-related osteonecrosis of the jaw (MRONJ), predominantly in the mandible, characterized by the presence of bony sequestrum, bone sclerosis, increased periodontal ligament space, osteolytic lesions, and osteomyelitis as observed in imaging analyses. For non-MRONJ lesions, the mandible also exhibited the highest frequency of asymptomatic bone alterations. These ranged from "punched-out" osteolytic lesions or "soap bubble" lesions to solitary bone lesions, areas of bone sclerosis, abnormalities of the hard palate, osteoporosis, non-healed alveoli, and cortical bone rupture. Conclusion: MM patients treated with bisphosphonates display radiographic patterns of maxillomandibular bone lesions. These patterns aid in diagnosis and facilitate early and targeted treatment, thereby contributing to improved morbidity outcomes for these patients.