• Title/Summary/Keyword: discontinuous group

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MICROLEAKAGE EVALUATION IN AMALGAM RESTORATIONS USED WITH BONDING AGENTS (수종의 접착제를 사용한 아말감 수복시의 미세 변연 누출에 관한 연구)

  • Choi, Sang-Cheol;Park, Joon-Il;Kwom, Hyuk-Choon
    • Restorative Dentistry and Endodontics
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    • v.22 no.1
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    • pp.447-463
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    • 1997
  • The purpose of this study was to evaluate the effectiveness of copal varnish and five bonding agents(Scotchbond Multi-Purpose Plus Dental Adhesive System, Panavia 21, All Bond 2, Superbond D-Liner II plus, Fuji Duet) in reducing microleakage under amalgam restorations. Class V cavity were prepared on both buccal and lingual surface of sixty extracted human molars with cementum margin and were filled with different kinds of liners and amalgam. All teeth were stored at $37^{\circ}C$ in physiologic saline solution. After 1 week they were thermally stressed for 500 cycles between 5 and $55^{\circ}C$ in baths containing 0.5 % basic fuchsin dye. The dye penetrations were observed with a stereomicroscope. Scanning electron micrographs were taken of representative tooth sections from each group to assess the nature of the tooth/liner/amalgam interface. The statistical test were applied to the results using a one way analysis variance (ANOVA) and Duncan's multiple range test. The results were as follows ; 1. In all groups, the enamel margin showed significantly lower leakage value than the cementum margin (p<0.05). 2. At the dentin and enamel margins, the leakage value of Copalite-lined group showed significantly higher than that of no liner group (p<0.05), but showed significantly lower than that of bonding agent lined-groups (p<0.05). 3. There was no significant difference between the bonding agent lined-groups (p>0.05). 4. On the backscattered scanning electron microscopy observation, discontinuous gaps were observed between amalgam and dentin in the bonding agent-lined amalgam restorations and the bonding agents appeared to fill the gap space and were mixed with amalgam particles. At the amalgam/tooth interface, unsealed dentin and continuous gaps were found in both unlined and Copalite-lined restorations.

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Discontinuous Percoll Gradients Enrich X-Bearing Porcine Sperms and Female Embryos (불연속 Percoll 원심분리에 의한 돼지 X-정자와 자성배아에 관한 연구)

  • Shim, Dae-Yong;Yoo, Seong-Jin;Kang, Han-Seung;Yoo, Jeong-Min;Lee, Chae-Kwan;Kang, Sung-Goo
    • Development and Reproduction
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    • v.5 no.1
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    • pp.47-52
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    • 2001
  • Predetermination of sex in livestock of offpring is in great demand and is of critical importance to providing for the most efficient production of the animal ariculture. Such a sexing techlology would also enhance the economy of conventional artificial insemination(AI) and aid the porcine industry. The purpose of this study was to evaluate the efficiency of enriching X-bearing porcine sperm using discontinuous percoll gradients and PCR mefhod. Semen was collected from mature boars of proven fertility center (AI center KimHae). Sperm was leaded on the isotonic discontinuous percoll gradient and then it was centrifuged at 120 ${\times}$ g for 20 minutes. After centrifugation, sperm included in each fraction were recovered (7${\times}$10$^6$ sperms/ml) and then sperm genomic DNA was extractedfor the PCR. SRY gene was used to evaluate the ratio between X and Y sperm in the separated fractions. Ju viro ffrtilization wascarried out by adding the unseparated sperm (control) or separated (experimental poop) to the matured oocytes in TCM-199. Embryos for sex determination were obtained at 2 cell stage and then was used for SRY gene amplification. After centrifugation of discontinuous percoll gradient, the most motile sperm was obtained at 95% fiaction (94.4% ${\pm}$ 5.1%, p < 0.01). The PCR analysis evaluated that 30%, 50% and 65% fractions were Y sperm rich, whereas 80% and 95% fractions were X sperm rich. PCR analysis with each porcineembryo showed that 33.3% of control and 66.7% of experimental group were determined as female embryos. In conclusion, in vitro matured oocytes inseminated with sperms (95% fraction) prepared by percoll gradient centrifugation showed high fertilization rates and female embryos than control sperms.

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Prototype Extraction for the Categorization of Lotus and Crane Patterns Using Qualitative and Quantitative Approaches (질적, 양적 접근방법에 의한 연화문, 사문의 분류원형 추출)

  • 장수경;김재숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.6
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    • pp.1016-1026
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    • 1996
  • The purpose of this study was to extract protypes from features and concrete images of Lotus and Crane patterns. A qualitative and a quantitative methods were used. Qualitative informations were obtained from depth Interviews for pattern selection and feature extraction, and quantitative informations from a quail-experiment for pattern caregorization. The subjects were 20 female design students and non-design, students in Teajon. The results were summerized into a similarity metrix which was interpreted by the cluster analysis and the multi-dimensional scling(MDS). The patterns for the study were grouped into 8 clusters. Four dimensions were chosen for the MDS. The location of each pattern was visualized in a 2-dimesional spaces and the location of each cluster in a 3-dimensional spaces. The first dimension, "Lotus" vs "Crane" refired to pattern types, and the second dimension, "realistic" vs "transformable", the transformability. The third dimension, "simple" vs "complex", refired to the degree of simplification, and the forth dimension, "continuous" vs "discontinuous", continuity. The results of the Quantitative analysis could be summerized into 3-level prototype hiararchy In the first level, the patterns were devided clearly into two groups. Lotus and Crane by pattern types. In the second levelk, each group was devided into twosubgroups by continuity. In the third, each subgroup was divided into four subgroups by transformability and the degree of simplification. Four protypes, the final targets of the present study, were extracted from the third level. The are Stylized, Realistic, Decorative, Abstract types.d from the third level. The are Stylized, Realistic, Decorative, Abstract types.

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Fuzzy-Sliding Mode Speed Control for Two Wheels Electric Vehicle Drive

  • Nasri, Abdelfatah;Hazzab, Abdeldjabar;Bousserhane, Ismail Khalil;Hadjeri, Samir;Sicard, Pierre
    • Journal of Electrical Engineering and Technology
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    • v.4 no.4
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    • pp.499-509
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    • 2009
  • Electric vehicles (EV) are developing fast during this decade due to drastic issues on the protection of environment and the shortage of energy sources, so new technologies allow the development of electric vehicles (EV) by means of electric motors associated with static converters. The proposed propulsion system consists of two induction motors (IM) that ensure the drive of the two back driving wheels. The electronic differential system ensures the robust control of the vehicle behavior on the road. It also allows controlling, independently, every driving wheel to turn at different speeds in any curve. This paper presents the study of an hybrid Fuzzy-sliding mode control (SMC) strategy for the electric vehicle driving wheels, stability improvement, in which the fuzzy logic system replace the discontinuous control action of the classical SMC law. Our electric vehicle fuzzy-sliding mode control's simulated in Matlab SIMULINK environment, the results obtained present the efficiency of the proposed control with no overshoot, the rising time is perfected with good disturbances rejections comparing with the classical control law.

Finite Element Analysis of the Neutron Transport Equation in Spherical Geometry (구형에서 중성자 수송방정식의 유한요소법에 의한 해석)

  • Kim, Yong-Ill;Kim, Jong-Kyung;Suk, Soo-Dong
    • Nuclear Engineering and Technology
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    • v.24 no.3
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    • pp.319-328
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    • 1992
  • The Galerkin formulation of the finite element method is applied to the integral law of the first-order form of the one-group neutron transport equation in one-dimensional spherical geometry. Piecewise linear or quadratic Lagrange polynomials are utilized in the integral law for the angular flux to establish a set of linear algebraic equations. Numerical analyses are performed for the scalar flux distribution in a heterogeneous sphere as well as for the criticality problem in a uniform sphere. For the criticality problems in the uniform sphere, the results of the finite element method, with the use of continuous finite elements in space and angle, are compared with the exact solutions. In the heterogeneous problem, the scalar flux distribution obtained by using discontinuous angular and spatical finite elements is in good agreement with that from the ANISN code calculation.

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COMPUTATIONAL EFFICIENCY OF A MODIFIED SCATTERING KERNEL FOR FULL-COUPLED PHOTON-ELECTRON TRANSPORT PARALLEL COMPUTING WITH UNSTRUCTURED TETRAHEDRAL MESHES

  • Kim, Jong Woon;Hong, Ser Gi;Lee, Young-Ouk
    • Nuclear Engineering and Technology
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    • v.46 no.2
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    • pp.263-272
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    • 2014
  • Scattering source calculations using conventional spherical harmonic expansion may require lots of computation time to treat full-coupled three-dimensional photon-electron transport in a highly anisotropic scattering medium where their scattering cross sections should be expanded with very high order (e.g., $P_7$ or higher) Legendre expansions. In this paper, we introduce a modified scattering kernel approach to avoid the unnecessarily repeated calculations involved with the scattering source calculation, and used it with parallel computing to effectively reduce the computation time. Its computational efficiency was tested for three-dimensional full-coupled photon-electron transport problems using our computer program which solves the multi-group discrete ordinates transport equation by using the discontinuous finite element method with unstructured tetrahedral meshes for complicated geometrical problems. The numerical tests show that we can improve speed up to 17~42 times for the elapsed time per iteration using the modified scattering kernel, not only in the single CPU calculation but also in the parallel computing with several CPUs.

Time-Matching Poisson Multi-Bernoulli Mixture Filter For Multi-Target Tracking In Sensor Scanning Mode

  • Xingchen Lu;Dahai Jing;Defu Jiang;Ming Liu;Yiyue Gao;Chenyong Tian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.6
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    • pp.1635-1656
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    • 2023
  • In Bayesian multi-target tracking, the Poisson multi-Bernoulli mixture (PMBM) filter is a state-of-the-art filter based on the methodology of random finite set which is a conjugate prior composed of Poisson point process (PPP) and multi-Bernoulli mixture (MBM). In order to improve the random finite set-based filter utilized in multi-target tracking of sensor scanning, this paper introduces the Poisson multi-Bernoulli mixture filter into time-matching Bayesian filtering framework and derive a tractable and principled method, namely: the time-matching Poisson multi-Bernoulli mixture (TM-PMBM) filter. We also provide the Gaussian mixture implementation of the TM-PMBM filter for linear-Gaussian dynamic and measurement models. Subsequently, we compare the performance of the TM-PMBM filter with other RFS filters based on time-matching method with different birth models under directional continuous scanning and out-of-order discontinuous scanning. The results of simulation demonstrate that the proposed filter not only can effectively reduce the influence of sampling time diversity, but also improve the estimated accuracy of target state along with cardinality.

THE STUDY ON SHEAR BOND STRENGTHS OF VARIOUS ONE-BOTTLE DENTIN ADHESIVES (수종의 One-bottle 상아질 결합제의 전단 결합 강도에 관한 연구)

  • Oh, So-Hee;Kim, Jong-Soo;Kwon, Soon-Won
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.4
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    • pp.553-565
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    • 2001
  • One-bottle adhesive system was recently developed in order to simplify the clinical skills and save chair time after continuous improvements on dentin bonding agents. To test the shear bond strength of a new "one-bottle adhesive" system to bovine dentin various commercially available one-bottle adhesives(Prime & Bond $2.1^{(R)}$, One Coat $Bond^{(R)}$, Syntac $Sprint^{(R)}$, Single $Bond^{(R)}$) were included for comparison. And we observe the interfacial morphology by scanning electron microscope. The results were as follows; 1. Group II (One Coat $Bond^{(R)}$) showed higher shear bond strength than group I (Prime & Bond $2.1^{(R)}$), group III(Syntac $Sprint^{(R)}$), and group IV(Single $Bond^{(R)}$), but no statistically significant difference was founded between groups(p>.05). 2. Relating reverse-cone shape resin tags were observed in samples of all groups under SEM. We could observed hybrid layer, resin tag and many lateral branches in every group. But, we observed in group III rare lateral branched than other three groups, and discontinuous hybrid layer.

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Enhancing the Seismic Performance of Multi-storey Buildings with a Modular Tied Braced Frame System with Added Energy Dissipating Devices

  • Tremblay, R.;Chen, L.;Tirca, L.
    • International Journal of High-Rise Buildings
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    • v.3 no.1
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    • pp.21-33
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    • 2014
  • The tied braced frame (TBF) system was developed to achieve uniform seismic inelastic demand along the height of multi-storey eccentrically braced steel frames. A modular tied braced frame (M-TBF) configuration has been recently proposed to reach the same objective while reducing the large axial force demand imposed on the vertical tie members connecting the link beams together in TBFs. M-TBFs may however experience variations in storey drifts at levels where the ties have been removed to form the modules. In this paper, the possibility of reducing the discontinuity in displacement response of a 16-storey M-TBF structure by introducing energy dissipating (ED) devices between the modules is examined. Two M-TBF configurations are investigated: an M-TBF with two 8-storey modules and an M-TBF with four 4-storey modules. Three types of ED devices are studied: friction dampers (FD), buckling restrained bracing (BRB) members and self-centering energy dissipative (SCED) members. The ED devices were sized such that no additional force demand was imposed on the discontinuous tie members. Nonlinear response history analysis showed that all three ED systems can be used to reduce discontinuities in storey drifts of M-TBFs. The BRB members experienced the smallest peak deformations whereas minimum residual deformations were obtained with the SCED devices.

Complex Segregation Analysis of Categorical Traits in Farm Animals: Comparison of Linear and Threshold Models

  • Kadarmideen, Haja N.;Ilahi, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.8
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    • pp.1088-1097
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    • 2005
  • Main objectives of this study were to investigate accuracy, bias and power of linear and threshold model segregation analysis methods for detection of major genes in categorical traits in farm animals. Maximum Likelihood Linear Model (MLLM), Bayesian Linear Model (BALM) and Bayesian Threshold Model (BATM) were applied to simulated data on normal, categorical and binary scales as well as to disease data in pigs. Simulated data on the underlying normally distributed liability (NDL) were used to create categorical and binary data. MLLM method was applied to data on all scales (Normal, categorical and binary) and BATM method was developed and applied only to binary data. The MLLM analyses underestimated parameters for binary as well as categorical traits compared to normal traits; with the bias being very severe for binary traits. The accuracy of major gene and polygene parameter estimates was also very low for binary data compared with those for categorical data; the later gave results similar to normal data. When disease incidence (on binary scale) is close to 50%, segregation analysis has more accuracy and lesser bias, compared to diseases with rare incidences. NDL data were always better than categorical data. Under the MLLM method, the test statistics for categorical and binary data were consistently unusually very high (while the opposite is expected due to loss of information in categorical data), indicating high false discovery rates of major genes if linear models are applied to categorical traits. With Bayesian segregation analysis, 95% highest probability density regions of major gene variances were checked if they included the value of zero (boundary parameter); by nature of this difference between likelihood and Bayesian approaches, the Bayesian methods are likely to be more reliable for categorical data. The BATM segregation analysis of binary data also showed a significant advantage over MLLM in terms of higher accuracy. Based on the results, threshold models are recommended when the trait distributions are discontinuous. Further, segregation analysis could be used in an initial scan of the data for evidence of major genes before embarking on molecular genome mapping.