• Title/Summary/Keyword: Dimensional Control

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Does the palatal vault form have an influence on the scan time and accuracy of intraoral scans of completely edentulous arches? An in-vitro study

  • Osman, Reham;Alharbi, Nawal
    • The Journal of Advanced Prosthodontics
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    • v.14 no.5
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    • pp.294-304
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    • 2022
  • PURPOSE. The purpose of this study was to evaluate the influence of different palatal vault configurations on the accuracy and scan speed of intraoral scans (IO) of completely edentulous arches. MATERIALS AND METHODS. Three different virtual models of a completely edentulous maxillary arch with different palatal vault heights- Cl I moderate (U-shaped), Cl II deep (steep) and Cl III shallow (flat)-were digitally designed using CAD software (Meshmixer; Autodesk, USA) and 3D-printed using SLA-based 3D-printer (XFAB; DWS, Italy) (n = 30; 10 specimens per group). Each model was scanned using intraoral scanner (Trios 3; 3ShapeTM, Denmark). Scanning time was recorded for all samples. Scanning accuracy (trueness and precision) were evaluated using digital subtraction technique using Geomagic Control X v2020 (Geomagic; 3DSystems, USA). One-way analysis of variance (ANOVA) test was used to detect differences in scanning time, trueness and precision among the test groups. Statistical significance was set at α = .05. RESULTS. The scan process could not be completed for Class II group and manufacturer's recommended technique had to be modified. ANOVA revealed no statistically significant difference in trueness and precision values among the test groups (P=.959 and P=.658, respectively). Deep palatal vault (Cl II) showed significantly longer scan time compared to Cl I and III. CONCLUSION. The selection of scan protocol in complex cases such as deep palatal vault is of utmost importance. The modified, adopted longer path scan protocol of deep vault cases resulted in increased scan time when compared to the other two groups.

Development of Preventive Self-Management Knowledge Related to Premature Labor (PSMK-PL) Scale for Women of Childbearing Age : An Item Response Theory Approach (가임 여성의 조기진통에 대한 예방적 자가관리 지식 측정 도구 개발: 문항반응이론 적용)

  • Kim, Sun-Hee;Lee, Yu-Jin
    • The Journal of the Korea Contents Association
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    • v.22 no.9
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    • pp.439-450
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    • 2022
  • Purpose: This study was to develop the Preventive Self-Management Knowledge related to Premature Labor (PSMK-PL) scale for women of childbearing age. Methods: Preliminary items were developed based on the literature and interview results of those who experienced premature labor. The online survey was conducted and the data of 250 women were analyzed using the DIMTEST and DETECT programs by applying the item response theory. Internal consistency reliability was analyzed with Cronbach's alpha (95% CI). Results: Among the 30 preliminary items, six items were deleted. The difficulty and discrimination of the 24 final three-dimensional scales were all acceptable, respectively. Cronbach's alpha (95% CI) was .89 (.87~.91). Conclusion: The PSMK-PL scale generally consisted of items with validity, and the reliability was acceptable.

Elevated plasma α1-antichymotrypsin is a biomarker candidate for malaria patients

  • Young Yil, Bahk;Sang Bong, Lee;Jong Bo, Kim;Tong-Soo, Kim;Sung-Jong, Hong;Dong Min, Kim;Sungkeun, Lee
    • BMB Reports
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    • v.55 no.11
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    • pp.571-576
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    • 2022
  • Advancements in the field of proteomics have provided opportunities to develop diagnostic and therapeutic strategies against various diseases. About half of the world's population remains at risk of malaria. Caused by protozoan parasites of the genus Plasmodium, malaria is one of the oldest and largest risk factors responsible for the global burden of infectious diseases with an estimated 3.2 billion persons at risk of infection. For epidemiological surveillance and appropriate treatment of individuals infected with Plasmodium spp., timely detection is critical. In this study, we used combinations of depletion of abundant plasma proteins, 2-dimensional gel electrophoresis (2-DE), image analysis, LC-MS/MS and western blot analysis on the plasma of healthy donors (100 individuals) and vivax and falciparum malaria patients (100 vivax malaria patients and 8 falciparum malaria patients). These analyses revealed that α1-antichymotrypsin (AACT) protein levels were elevated in vivax malaria patient plasma samples (mean fold-change ± standard error: 2.83 ± 0.11, based on band intensities), but not in plasma from patients with other mosquito-borne infectious diseases. The results of AACT immunoblot analyses showed that AACT protein was significantly elevated in vivax and falciparum malaria patient plasma samples (≥ 2-fold) compared to healthy control donor plasma samples, which has not been previously reported.

Ground Test of Docking Phase for Nanosatellite (초소형위성 지상 환경 도킹 시험)

  • Kim, Hae-Dong;Choi, Won-Sub;Kim, Min-Ki;Kim, Jin-Hyung;Kim, KiDuck;Kim, Ji-Seok;Cho, Dong-Hyun
    • Journal of Space Technology and Applications
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    • v.1 no.1
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    • pp.7-22
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    • 2021
  • In this paper, we describe the results of the docking phase test in the ground environment of the rendezvous/docking technology verification satellite under development for the first time in Korea. rendezvous/docking technology is a high-level technology in space technology, which is also very important for accessing and performing tasks on relative objects in space orbit. In this paper, we describe the ground test results that the chaser finally docks the fixed target using an air bearing device. Based on the thrust control algorithm in the docking phase and the relative object recognition and relative distance estimation algorithm using visual-based sensors validated in this paper, we intend to use them for later expansion to rendezvous/docking algorithms in three-dimensional space for testing in space.

Clinical assessment of various imaging systems for dental plaque scoring after the use of 3 different toothpastes

  • Simge Meseli;Sergen Ekenel;Bora Korkut;Burak Aksu;Dilek Tagtekin;Funda Yanikoglu
    • Imaging Science in Dentistry
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    • v.53 no.3
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    • pp.209-216
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    • 2023
  • Purpose: This study was conducted to compare dental plaque scores obtained through clinical examinations and various imaging techniques, as well as to assess the effectiveness of herbal and conventional toothpastes for plaque removal. Materials and Methods: Thirty volunteers were divided into 3 groups. Each group was given a different toothpaste (from 2 herbal toothpastes and a conventional toothpaste) with which to brush their teeth for 21 days. Both initially and after brushing, dental plaque samples were collected, and plaque on the buccal surfaces of anterior teeth was scored using several imaging systems after staining with a disclosing agent. Specifically, digital dental photography, intraoral digital scanning, and FluoreCam imaging were employed to capture intraoral images. The Turesky Modified Quigley-Hein Plaque Index was used for clinical examination and image analysis. Quantitative polymerase chain reaction analyses and correlational assessments between clinical examination and imaging scores were conducted before and after toothpaste use. The Shapiro-Wilk test and Pearson correlations were utilized. Results: The lowest mean value was observed in the clinical examination without staining, while the highest was obtained using the FluoreCam method. No significant change was found in the level of any microorganism assessed following toothpaste use (P<0.05), with the exception of a decrease in S. mutans levels after using conventional toothpaste (P<0.05). Conclusion: Herbal toothpaste demonstrated plaque-removal effectiveness comparable to that of conventional toothpaste. The use of imaging methods for measuring plaque index has been suggested as a means to educate patients about plaque control and promote ongoing oral care.

An aluminum-based reflective nanolens array that enhances the effectiveness of a continuous-flow ultraviolet disinfection system for livestock water

  • Changhoon Chai;Jinhyung Park
    • Journal of Animal Science and Technology
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    • v.65 no.1
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    • pp.258-270
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    • 2023
  • Climate change has worsened droughts and floods, and created conditions more likely to lead to pathogen contamination of surface water and groundwater. Thus, there is a growing need to disinfect livestock water. Ultraviolet (UV) irradiation is widely accepted as an appropriate method for disinfecting livestock water, as it does not produce hazardous chemical compounds and kills pathogens. However, UV-based disinfection inevitably consumes electricity, so it is necessary to improve UV disinfection effectiveness. Aluminum-based reflective nanolens arrays that enhanced the effectiveness of a continuous-flow UV water disinfection system were developed using electrochemical and chemical processes, including electropolishing and two-step anodization. A continuous UV disinfection system was custom designed and the parts were produced using a three-dimensional printer. Electropolished aluminum was anodized at 40 and 80 V in 0.3 M oxalic acid, at 120 and 160 V in 1.0 M phosphoric acid, and at 200 and 240 V in 1.5 M citric acid. The average nanolens diameters (D) of the aluminum-based reflective nanolens arrays prepared using 40, 80, 120, 160, 200, and 240 V anodization were 95.44, 160.98, 226.64, 309.90, 296.32, and 339.68 nm, respectively. Simple UV reflection behind irradiated water disinfected Escherichia coli O157:H7 in water more than did the non-reflective control. UV reflection and focusing behind irradiated water using an aluminum-based reflective nanolens array disinfected E. coli O157:H7 more than did simple UV reflection. Such enhancement of the UV disinfection effectiveness was significantly effective when a nanolens array with D 226.64 nm, close to the wavelength of the irradiated UV (254 nm), was used.

Effect of Interconnect Structure on the Cell Performance in Anode-supported Tubular SOFC Using Three-dimensional Simulation (3차원 수치모사를 통한 연료극 지지식 관형 고체산화물 연료전지의 전지 성능에 대한 연결재 구조 효과)

  • Hwang, Ji-Won;Lee, Jeong-Yong;Jo, Dong-Hyun;Jung, Hyun-Wook;Kim, Sung-Hyun
    • Clean Technology
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    • v.16 no.4
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    • pp.297-303
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    • 2010
  • Effect of interconnect structure on the cell performance in anode-supported tubular solid oxide fuel cell (SOFC) has been investigated in this study, employing the Fluent CFD solver. For the robust and reliable theoretical analysis corroborating experimental results, it is of great importance to elucidate the role of interconnect which is electrically connected with electrodes on the cell characteristics. From the fact that the thin interconnect provides the enhanced cell performance, it is revealed that the interconnect thickness is a key parameter that is able to effectively control the ohmic resistance. Under the constant thickness condition, the cell performance does not considerably change with the variation of interconnect width. This is because the current passage along with circumferential direction is not effectively altered by the change of interconnect width in tubular SOFC system.

Origin of Tearing Paths in Transferred Graphene by H2 Bubbling Process and Improved Transfer of Tear-Free Graphene Films U sing a Heat Press

  • Jinsung Kwak
    • Korean Journal of Materials Research
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    • v.32 no.12
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    • pp.522-527
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    • 2022
  • Among efforts to improve techniques for the chemical vapor deposition of large-area and high-quality graphene films on transition metal substrates, being able to reliably transfer these atomistic membranes onto the desired substrate is a critical step for various practical uses, such as graphene-based electronic and photonic devices. However, the most used approach, the wet etching transfer process based on the complete etching of metal substrates, remains a great challenge. This is mainly due to the inevitable damage to the graphene, unintentional contamination of the graphene layer, and increased production cost and time. Here, we report the systematic study of an H2 bubbling-assisted transfer technique for graphene films grown on Cu foils, which is nondestructive not only to the graphene film but also to the Cu substrate. Also, we demonstrate the origin of the graphene film tearing phenomenon induced by this H2 bubbling-assisted transfer process. This study reveals that inherent features are produced by rolling Cu foil, which cause a saw-like corrugation in the poly(methyl methacrylate) (PMMA)/graphene stack when it is transferred onto the target substrate after the Cu foil is dissolved. During the PMMA removal stage, the graphene tearing mainly appears at the apexes of the corrugated PMMA/graphene stack, due to weak adhesion to the target substrate. To address this, we have developed a modified heat-press-assisted transfer technique that has much better control of both tearing and the formation of residues in the transferred graphene films.

Prediction of Residual Settlement of Ground Improved by Vertical Drains Using the Elasto-Viscous Consolidation Model - Application for Field Condition - (탄-점성 압밀이론에 의한 버티칼 드레인 타설지반의 잔류침하 예측 (II) - 현장조건에의 적용 -)

  • Baek, Won-Jin;Lee, Kang-Il;Kim, Woo-Jin
    • Journal of the Korean Geotechnical Society
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    • v.23 no.6
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    • pp.85-95
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    • 2007
  • In this study, in order to propose the prediction method of the residual settlement of clayey ground improved by vertical drains, a series of numerical analyses for a model ground were carried out using the elasto-viscous consolidation model. And the effects of ground improvement conditions of the ratio of effective radii $(r_e/r_w)$, consolidation pressure $({\Delta}p)$ on normally consolidated state, and the OCR (overconsolidation ratio) on overconsolidated state to reduce the residual settlement in three-dimensional consolidation by vertical drains were investigated by performing a series of numerical analyses. Furthermore, based on the results of a series of numerical analyses for the model ground, the predicting method of the residual settlement of clayey ground with vertical drains and the determination method of the value of OCR required to control the residual settlement within an acceptable value are proposed.

Data Assimilation of Aeolus/ALADIN Horizontal Line-Of-Sight Wind in the Korean Integrated Model Forecast System (KIM 예보시스템에서의 Aeolus/ALADIN 수평시선 바람 자료동화)

  • Lee, Sihye;Kwon, In-Hyuk;Kang, Jeon-Ho;Chun, Hyoung-Wook;Seol, Kyung-Hee;Jeong, Han-Byeol;Kim, Won-Ho
    • Atmosphere
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    • v.32 no.1
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    • pp.27-37
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    • 2022
  • The Korean Integrated Model (KIM) forecast system was extended to assimilate Horizontal Line-Of-Sight (HLOS) wind observations from the Atmospheric Laser Doppler Instrument (ALADIN) on board the Atmospheric Dynamic Mission (ADM)-Aeolus satellite. Quality control procedures were developed to assess the HLOS wind data quality, and observation operators added to the KIM three-dimensional variational data assimilation system to support the new observed variables. In a global cycling experiment, assimilation of ALADIN observations led to reductions in average root-mean-square error of 2.1% and 1.3% for the zonal and meridional wind analyses when compared against European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS) analyses. Even though the observable variable is wind, the assimilation of ALADIN observation had an overall positive impact on the analyses of other variables, such as temperature and specific humidity. As a result, the KIM 72-hour wind forecast fields were improved in the Southern Hemisphere poleward of 30 degrees.