• Title/Summary/Keyword: margin consistency

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An Experimental Study on Margin Consistency of Prosthesis According to the Continued Time of Casting-Ring in the course of the Casting of Dental Alloy (치과용 합금 주조 시 주조링의 계류시간에 따른 보철물의 변연 적합도 실험에 관한 연구)

  • Hwang, Seong-Sig;Lee, Sang-Hyeok
    • Journal of Technologic Dentistry
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    • v.23 no.2
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    • pp.179-188
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    • 2002
  • With regard to the manufacture of dental prosthesis, all the dental mechanism is of vital significance at the aspect of activating its function by fixing the prosthesis to Patient's oral cavity. However, if there we will take our immediate action without the discretion about its process none the less for the importance of dental mechanism, then we might have a serious problem. Accordingly, there need to pay attention to the dilatability makes up for the shrinkage state occurring by the feature of metal materials and manufacturing process which appeared in the process of dental mechanism, which eventually is expected to playa very important role in casting a dental prosthesis appropriate to one's oral tissue. This study was designed to take into account of the effects on margin consistency of prosthesis according to the continued time of casting-ring in the course of the casting of dental alloy. For this, the researcher made an experiment on the casting of dental alloy, its dilatability, and the change of phase. The results of this study were as follows: First, the researcher could see that the sample which was cast under the condition of $650^{\circ}C/20$ Minutes(the continued time) was far superior to others at the aspect of margin consistency. Second, according to the measurement of expansion coefficient by Dilatometer, the researcher perceived the fact that the expansion-coefficient showed a maximum of $37.1{\mu}m$ considering the sample's length which was cast with ordinary temperature under the condition of $650^{\circ}C/20$ Minutes. Third, from the result of X-ray diffraction under the condition of $650^{\circ}C/20$ Minutes(the continued time), the researcher could find that there's no difference between the change of phase and its intensity. As mentioned above, the researcher could ascertain the fact that its contraction don't give rise to the change of phase.

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A Note on Linear SVM in Gaussian Classes

  • Jeon, Yongho
    • Communications for Statistical Applications and Methods
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    • v.20 no.3
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    • pp.225-233
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    • 2013
  • The linear support vector machine(SVM) is motivated by the maximal margin separating hyperplane and is a popular tool for binary classification tasks. Many studies exist on the consistency properties of SVM; however, it is unknown whether the linear SVM is consistent for estimating the optimal classification boundary even in the simple case of two Gaussian classes with a common covariance, where the optimal classification boundary is linear. In this paper we show that the linear SVM can be inconsistent in the univariate Gaussian classification problem with a common variance, even when the best tuning parameter is used.

Ultrasonogram as a Diagnostic Modality in Thyroid Tumors (갑상선 결절의 진단에서 초음파의 유용성)

  • Cho Yong-Hwan;Hur Jun;Yoon Dae-Kun;Kim Jeong-Jin;Park Yoon-Kyu;Yoon Dae-Won;Park Sung-Gil
    • Korean Journal of Head & Neck Oncology
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    • v.17 no.1
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    • pp.42-47
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    • 2001
  • Purpose: To evaluate the usefulness of ultrasonogram as a preoperative diagnostic tool in thyroid nodular diseases, this study was carried out. Materials and Methods: From January 1998 to December 1999, 51 patients who underwent thyroidectomy were analyzed retrospectively. We compared the finally histopathological results to ultrasonographical findings such as internal consistency, multiplicity of nodules, nodular ehogenicity, nodular capsule or margin, calcification of nodules. Results: There were 47 females and 4 males with 25 benign tumor, 23 malignant tumor and 3 occult carcinoma in histopathological diagnosis. The solid tumors in ultrasonography carried a probability of malignancy as 66.7%(16/24 cases) whereas cystic or mixed tumors as 16.7%(1/6cases) or 23.8%(5/21cases) (p=0.006). The single nodular diseases carried a high probability of malignancy as 50%(13/26cases) whereas multiple diseases as 28.6%(6/21cases). The hypoechogenicity of thyroid nodular disease showed a probability of malignancy as 60%(9/15cases) whereas mixed-echogenicity as 36.4%(4/11cases). The nodules with poorly-defined margin in ultrasonographic findings showed higher probability of malignancy as 63.6% (7/11cases) than the nodules with well -defined margin as 26.5%(9/34 cases) (p=0.025). The nodules with calcification in ultrasonographic findings were represented to high probability of malignancy as 70.6%(12/17cases) compared to those without calcification as 29.4%(10/34cases) (p=0.005). The differency between ultrasonic and histopathological diagnosis was high in solid nodules(33%), 3-4cm sized nodules (28.6%) and mixed echogenecity(27.3%) whereas low in complex nodules with cystic and solid nature(4.8%), 2-3 cm sized nodules(8.3%) and pooly defined margin(9.1%). The accuracies of sonography in differentiating malignacy from benign thyroid nodules were 7.1% of false positivity, 39.1% of false negativity, 60.9% of sensitivity, 92.9% of specificity and 78.4% of accuracy. Conclusion: Sonographic examination was relatively excellent test as a preoperative diagnostic tool in thyroid nodular diseases when detailed checklists were applied such as internal consistency, multiplicity of nodules, nodular ehogenicity, nodular capsule or margin and calcification of nodules.

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A Fuel Spiking Test for the Surge Margin Measurement in Gas Turbine Engines

  • Lee, Jinkun;Kim, Chuntaek;Sooseok Yang;Lee, Daesung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.380-384
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    • 2004
  • A fuel spiking test was performed to measure the surge margin of the compressor in a gas turbine engine. During the test, fuel spiking signal was superimposed on the engine controller demand and the mixed signals were used to control a fuel line servo-valve. For the superimposition, a subsystem composed of a fuel controller and a function generator was used. During the fuel spiking test, the original scheduled fuel signals and the modified signals were compared to guarantee the consistency excluding the spiking signals. The spiking signals were carefully selected to maintain the engine speed constant. The fuel spiking effects were checked by three dynamic pressure sensors. Sensors were placed before the servo-valve, after the servo-valve, and after the compressor location, respectively. The modulations of the spiking signal duration and fuel flow rate were examined to make the- operating point approach the surge region. The real engine test was performed at the Altitude Engine Test Facility (AETF) in Korea Aerospace Research Institute (KARI). In the real engine test, fuel spiking signals with 25~50 ㎳ of spiking signal time and 17~46 % of base fuel flow rate condition were used. The dithering signal was 5~6 ㎃ at 490 Hz. The test results showed good agreement between the fuel spiking signals and the fuel line pressure signals. Also, the compressor discharge pressure signals showed fuel spiking effects and the changes of the operating point on the compressor characteristic map could be traced.

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Correlation between different methodologies used to evaluate the marginal adaptation of proximal dentin gingival margins elevated using a glass hybrid

  • Hoda S. Ismail;Brian R. Morrow;Ashraf I. Ali;Rabab El. Mehesen;Franklin Garcia-Godoy;Salah H. Mahmoud
    • Restorative Dentistry and Endodontics
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    • v.47 no.4
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    • pp.36.1-36.17
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    • 2022
  • Objectives: This study aimed to evaluate the effect of aging on the marginal quality of glass hybrid (GH) material used to elevate dentin gingival margins, and to analyze the consistency of the results obtained by 3 in vitro methods. Materials and Methods: Ten teeth received compound class II cavities with subgingival margins. The dentin gingival margins were elevated with GH, followed by resin composite. The GH/gingival dentin interfaces were examined through digital microscopy, scanning electron microscopy (SEM) using resin replicas, and according to the World Dental Federation (FDI) criteria. After initial evaluations, all teeth were subjected to 10,000 thermal cycles, followed by repeating the same marginal evaluations and energy dispersive spectroscopy (EDS) analysis for the interfacial zone of 2 specimens. Marginal quality was expressed as the percentage of continuous margin at ×200 for microscopic techniques and as the frequency of each score for FDI ranking. Data were analyzed using the paired sample t-test, Wilcoxon signed-rank test, and Pearson and Spearmen correlation coefficients. Results: None of the testing techniques proved the significance of the aging factor. Moderate and strong significant correlations were found between the testing techniques. The EDS results suggested the presence of an ion-exchange layer along the GH/gingival dentin interface of aged specimens. Conclusions: The marginal quality of the GH/dentin gingival interface defied aging by thermocycling. The replica SEM and FDI ranking results had stronger correlations with each other than either showed with the digital microscopy results.

4 Cases of Head and Neck Philomatricoma (두경부에 발생한 모기질종(Pilomatricoma) 4예)

  • Chung Phil-Sang;Woo Seung-Houn;Lee Sang-Hun;Myong Na-Hye;Lee Sang-Joon
    • Korean Journal of Head & Neck Oncology
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    • v.20 no.1
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    • pp.62-66
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    • 2004
  • Pilomatricoma is a benign neoplasm of the hair follicle origin which most common occur in the head and neck, particularly in the cheek and preauricular region. This neoplasm is superficially located and stony, hard consistency on palpation and sometimes shows reddish or bluish discoloration on the overlying skin. The diagnosis is confirmed by histopathologic examination. Radiologic evaluation is little diagnostic and fine needle aspiration biopsy often misdiagnose because both tissues from basaloid cell component and shadow cell component should be obtained for correct diagnosis. And Otolaryngologist should consider the possibility of philomatricoma when childhood or early adulthood persion visits with hard, supferficial mass on the parotid or cheek area. The treatment of choice is surgical excision with clear resection margin. In many instances, overlying skin excision is needed. We report 4 cases of philomatricoma arising from preauricular, cheek and posterior neck.

An Exploratory Study on the Disposable Sanitary Pads for User-Oriented Product Design (사용자 중심 제품설계를 위한 일회용 생리대의 탐색적 연구)

  • Jeon, Eun-Kyung;Moon, Ji-Hyun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.1
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    • pp.167-174
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    • 2010
  • This paper aims to examine the status of sizing specifications for disposable sanitary pads on the market and to offer information on product design that reflect the requests of consumer by gathering opinion through the practical experience of consumers. Seventy-six varieties of sanitary pads on market are measured and the evaluations of wearing comfort were investigated by the questionnaire and interview for sixty three varieties of sanitary pads. As a result, they were classified into five sizes related with length but vaguely related with thickness and width. Thickness is distinguished by the compressibility that is marked as slim or ultra slim by the same brand. However, there is no sizing consistency for all products. The result shows that there is some confusion for consumers to choose desired sizes, In addition, the perception of wearing is categorized into four factors that are product performance, size and fit, wearing feeling and margin of action, and adhesive property and wrapping. The manufacturing specifications for the sanitary pads on domestic market, the requests of consumers for sanitary pad design modifications, and proposals for follow-up studies were figured out through this research.

Satellite FEM Validation test for High Frequency Jitter Analysis

  • Oh, Shi-Hwan;Yong, Ki-Lyuk
    • Bulletin of the Korean Space Science Society
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    • 2008.10a
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    • pp.28.4-29
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    • 2008
  • The aim of the test is to provide an experimental basis to validate the prediction of the FEM for high frequency jitter analysis due to reaction wheel. The principle is to measure structural transfer functions between the input disturbances at RWA base plate and the accelerations near the end tips of payload, in a configuration close to the operational model. The spacecraft shall have to be suspended, in order to be representative of on-orbit boundary conditions. The results of the test shall be compared to the output of the FEM analysis, and if needed, local upgrades of the FEM and/or margin policy shall be defined in order to guarantee a good test/FEM consistency. Test results were compared with the transfer functions of the FEM, which is globally tuned based on the results of vibration test and consequently have lower damping coefficients values than 1% in the frequency range of 60~200Hz. The damping coefficients estimated from the figures of FRF test results are different from the theoretical FEM, but the magnitude trend of FRF of the test results is somewhat similar with the analytical, it is expected that the overall jitter effect of final estimation is nearly same with the preliminary analysis result in which the damping coefficients were assumed to be 1% for all modes in FEM.

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Development of 3-Dimensional Sight Distance Model for Highway Alignments (3차원 입체선형을 고려한 도로시거산정모형 개발에 관한 연구)

  • Park, Je-Jin;Choi, Joo-Yong;Ha, Tae-Jun
    • International Journal of Highway Engineering
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    • v.10 no.1
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    • pp.1-9
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    • 2008
  • Five bases for of highways are sight distance, vehicle stability, driver comfort, drainage and aesthetics. Among these bases, the sight distance is the most critical one in the highway alignment design. It is certain that highways and drivers' observation actions are 3-dimensional in nature. But, the highway alignment design and the sight distance analysis have been performed on 2-dimensional planes because of various constraints and complexity of calculating 3-dimensional sight distance. The purpose of this study is to derive a model for determining exact available sight distance in 3-D combined horizontal and vertical alignments. Application of the model is illustrated using numerical examples. The proposed model should be useful in quantifying the criteria for 3-D highway alignments.

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Antagonistic and growth promotion potential of endophytic bacteria of mulberry (Morus spp.)

  • Pratheesh Kumar, Punathil Meethal;Ramesh, Sushma;Thipeswamy, Thipperudraiah;Sivaprasad, Venkadara
    • International Journal of Industrial Entomology and Biomaterials
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    • v.31 no.2
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    • pp.107-114
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    • 2015
  • Endophytes provide multifarious benefits such as promotion of plant growth and yield, suppression of phyto-pathogens, phosphate solubilising and fixation nitrogen. A study has been carried out to explore growth promotion and antifungal activities of endophytes of mulberry (Morus spp.). Endophytic bacteria were isolated from mulberry plants and studied their cultural, morphological characters, growth promotion as well as their antifungal activity against Rhizoctonia bataticola and Fusarium oxysporum , two mulberry root rot associated pathogens. Except two isolates, all bacteria were colourless and the colony size of eight isolates was small. The margin of five isolates was irregular and the consistency of three isolates was creamy, six isolates was slimy and one was mucoid. Texture of seven isolates was convex and others were flat. Eight isolates were gram positive and the rest Gram negative, five were cocci and others were bacilli (rod shaped). Four isolates were motile and all were catalase positive and only three isolates were oxidase positive. Spore staining was positive only for two isolates. The growth promotion study showed that there was significant difference in root length and seedling length. The antagonistic effect of the bacterial isolates was tested against R. bataticola showed significant (p <0.05) influence of the bacteria, days after inoculation and their interaction on the inhibition of fungal growth. The isolate En-7 completely inhibited the fungus followed by En-5 (66.67%). The bacterial isolates significantly (p <0.05) inhibited growth of F. oxysporum in PDA. The mean inhibition was higher (70.45%) in case of En-7 followed by En-8 (68.65%) and En-10 (66.44%). The study reveals that some endophytic bacteria associated with mulberry have growth promotion and antifungal activity and could be explored for promotion of mulberry growth and managing root rot disease.