• Title/Summary/Keyword: and symmetric group

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Comparison of the condyle-fossa relationship between skeletal class III malocclusion patients with and without asymmetry: a retrospective three-dimensional cone-beam computed tomograpy study

  • Kim, Hyoun Oak;Lee, Won;Kook, Yoon-Ah;Kim, Yoonji
    • The korean journal of orthodontics
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    • v.43 no.5
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    • pp.209-217
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    • 2013
  • Objective: This study investigated whether temporomandibular joint (TMJ) condyle-fossa relationships are bilaterally symmetric in class III malocclusion patients with and without asymmetry and compared to those with normal occlusion. The hypothesis was a difference in condyle-fossa relationships exists in asymmetric patients. Methods: Group 1 comprised 40 Korean normal occlusion subjects. Groups 2 and 3 comprised patients diagnosed with skeletal class III malocclusion, who were grouped according to the presence of mandibular asymmetry: Group 2 included symmetric mandibles, while group 3 included asymmetric mandibles. Pretreatment three-dimensional cone-beam computed tomography (3D CBCT) images were obtained. Right- and left-sided TMJ spaces in groups 1 and 2 or deviated and non-deviated sides in group 3 were evaluated, and the axial condylar angle was compared. Results: The TMJ spaces demonstrated no significant bilateral differences in any group. Only group 3 had slightly narrower superior spaces (p < 0.001). The axial condylar angles between group 1 and 2 were not significant. However, group 3 showed a statistically significant bilateral difference (p < 0.001); toward the deviated side, the axial condylar angle was steeper. Conclusions: Even in the asymmetric group, the TMJ spaces were similar between deviated and non-deviated sides, indicating a bilateral condyle-fossa relationship in patients with asymmetry that may be as symmetrical as that in patients with symmetry. However, the axial condylar angle had bilateral differences only in asymmetric groups. The mean TMJ space value and the bilateral difference may be used for evaluating condyle-fossa relationships with CBCT.

Evaluation of Serum Symmetric Dimethylarginine Concentrations in Dogs with Chronic Mitral Valve Insufficiency

  • Kim, Nam-Kyun;Song, Joong-Hyun;Yu, Do-Hyeon;Hwang, Tae-Sung;Lee, Hee-Chun;Jung, Dong-In
    • Journal of Veterinary Clinics
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    • v.34 no.5
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    • pp.313-317
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    • 2017
  • Symmetric dimethylarginine (SDMA) is a new renal biomarker for kidney function. It is almost exclusively eliminated by renal filtration. The purpose of this retrospective study was to evaluate the changes in serum ceatinine (CREA), blood urea nitrogen (BUN) and SDMA concentrations in dogs with chronic mitral valve insufficiency (CMVI), according to the severity of CMVI. The evaluation of the severity of CMVI was performed according to the American College of Veterinary Internal Medicine (ACVIM) classification of heart failure. The dogs were classified into two groups: group 1 (ACVIM B; n = 11) and group 2 (ACVIM C; n = 15). In dogs with advanced CMVI, the serum SDMA concentrations were significantly increased above the normal reference range and were independent of body weight (BW), systolic blood pressure (SBP), or sex. No dog in either group had higher serum CREA concentrations than the upper limit. The serum SDMA concentration may be a better renal marker than serum CREA concentrations for the early diagnoses of renal dysfunction in dogs with CMVI.

THE HOMOLOGY HOMOMORPHISM INDUCED BY HARER MAP

  • Lee, Deogju;Song, Yongjin
    • Korean Journal of Mathematics
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    • v.19 no.4
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    • pp.409-421
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    • 2011
  • We study a natural map from the braid group to the mapping class group which is called Harer map. It is rather new and different from the classical map which was studied in 1980's by F. Cohen, J. Harer et al. We show that this map is homologically trivial for most coefficients by using the fact that this map factors through the symmetric group.

A Novel Authenticated Group Key Distribution Scheme

  • Shi, Run-hua;Zhong, Hong;Zhang, Shun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.935-949
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    • 2016
  • In this paper, we present a novel authenticated group key distribution scheme for large and dynamic multicast groups without employing traditional symmetric and asymmetric cryptographic operations. The security of our scheme is mainly based on the basic theories for solving linear equations. In our scheme, a large group is divided into many subgroups, where each subgroup is managed by a subgroup key manager (SGKM) and a group key generation center (GKGC) further manages all SGKMs. The group key is generated by the GKGC and then propagated to all group members through the SGKMs, such that only authorized group members can recover the group key but unauthorized users cannot. In addition, all authorized group members can verify the authenticity of group keys by a public one-way function. The analysis results show that our scheme is secure and efficient, and especially it is very appropriate for secure multicast communications in large and dynamic client-server networks.

Comparison of Glenohumeral Stabilization Exercise and Scapular Stabilization Exercise on Upper Extremity Stability, Alignment, Pain, Muscle Power and Range of Motion in Patients With Nonspecific Shoulder Pain

  • Jeon, Na-young;Chon, Seung-chul
    • Physical Therapy Korea
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    • v.23 no.4
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    • pp.38-46
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    • 2016
  • Background: Shoulder stabilization commonly involves two components: the glenohumeral stabilization exercise (GSE) and scapular stabilization exercise (SSE). Despite the fact that the shoulder stabilization has advantageous merit, to our knowledge, only a few studies have compared the superior of the GSE and the SSE. Objects: The purpose of this study was to assess the effects of GSE in patients with nonspecific shoulder pain. Methods: Thirty subjects with nonspecific shoulder pain were randomly divided into an experimental group and control group, each with 15 patients. The experimental group used an GSE, whereas the control group did SSE. All subjects were measured in shoulder stability, scapular symmetric alignment, pain, muscle power, and range of motion before and after the intervention. Results: GSE resulted in significantly better shoulder stability (p=.046, from $8.67{\pm}7.54$ score to $13.93{\pm}9.40$) in the experimental group compared with SSE in the control group. However, no significant effects were observed for scapular symmetric alignment including the angles of inferior scapular distance (p=.829) and inferior scapular height difference (p=.735), pain (p=.113), muscle power including shoulder flexion (p=.723) and abduction (p=.897) and range of motion including shoulder flexion (p=.853) and abduction (p=.472). Conclusion: These findings suggest that GSE may be more effective in increasing the shoulder stability than the SSE in patients with nonspecific shoulder pain, probably through a centralization effect on the shoulder mechanism.

Effect of Asymmetric Hot Rolling on the Texture Evolution of Fe-3%Si Steel

  • Na, Tae-Wook;Park, Hyung-Ki;Park, Chang-Soo;Joo, Hyung-Don;Park, Jong-Tae;Han, Heung Nam;Hwang, Nong-Moon
    • Metals and materials international
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    • v.24 no.6
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    • pp.1369-1375
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    • 2018
  • In Fe-3%Si steel, the hot rolling process affects not only the hot rolling texture but also the primary recrystallization texture. Here, the effect of asymmetric hot rolling was studied by comparing the difference in the texture evolved between asymmetric and symmetric hot rolling. The effect of asymmetric hot rolling on the texture of primary recrystallized Fe-3%Si steel was also studied. The symmetric hot rolling of Fe-3%Si steel produces a rotated cube texture at the center but Goss and copper textures near the surface. Asymmetric hot rolling tends to produce Goss and copper textures even at the center like the texture near the surface. After primary recrystallization, the dominant texture at the center changes from {001} <210> to {111} <112> and the new texture has a higher fraction of the grains which make the low energy boundary with Goss grains than that of symmetric hot rolling.

Near-elliptic Core Triangular-lattice and Square-lattice PCFs: A Comparison of Birefringence, Cut-off and GVD Characteristics Towards Fiber Device Application

  • Maji, Partha Sona;Chaudhuri, Partha Roy
    • Journal of the Optical Society of Korea
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    • v.18 no.3
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    • pp.207-216
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    • 2014
  • In this work, we report detailed numerical analysis of the near-elliptic core index-guiding triangular-lattice and square-lattice photonic crystal fiber (PCFs); where we numerically characterize the birefringence, single mode, cut-off behavior and group velocity dispersion and effective area properties. By varying geometry and examining the modal field profile we find that for the same relative values of $d/{\Lambda}$, triangular-lattice PCFs show higher birefringence whereas the square-lattice PCFs show a wider range of single-mode operation. Square-lattice PCF was found to be endlessly single-mode for higher air-filling fraction ($d/{\Lambda}$). Dispersion comparison between the two structures reveal that we need smaller lengths of triangular-lattice PCF for dispersion compensation whereas PCFs with square-lattice with nearer relative dispersion slope (RDS) can better compensate the broadband dispersion. Square-lattice PCFs show zero dispersion wavelength (ZDW) red-shifted, making it preferable for mid-IR supercontinuum generation (SCG) with highly non-linear chalcogenide material. Square-lattice PCFs show higher dispersion slope that leads to compression of the broadband, thus accumulating more power in the pulse. On the other hand, triangular-lattice PCF with flat dispersion profile can generate broader SCG. Square-lattice PCF with low Group Velocity Dispersion (GVD) at the anomalous dispersion corresponds to higher dispersion length ($L_D$) and higher degree of solitonic interaction. The effective area of square-lattice PCF is always greater than its triangular-lattice counterpart making it better suited for high power applications. We have also performed a comparison of the dispersion properties of between the symmetric-core and asymmetric-core triangular-lattice PCF. While we need smaller length of symmetric-core PCF for dispersion compensation, broadband dispersion compensation can be performed with asymmetric-core PCF. Mid-Infrared (IR) SCG can be better performed with asymmetric core PCF with compressed and high power pulse, while wider range of SCG can be performed with symmetric core PCF. Thus, this study will be extremely useful for designing/realizing fiber towards a custom application around these characteristics.

Effect of cylinder diameter and boat tail angle on the free vibration characteristics of a typical payload fairing

  • Ramamurti, V.;Rajarajan, S.;Rao, G. Venkateswara
    • Structural Engineering and Mechanics
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    • v.13 no.3
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    • pp.345-353
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    • 2002
  • Three noded plate and shell finite element and 3D beam element in conjunction with Lanczos method are used for studying the effect of boat tail angle on the free vibration characteristics of a typical payload fairing for three different cylinder diameters with height to diameter ratio 1.5. Configurations without boat tail structural member are also studied. One half of the one side fairing structure is considered for the analysis and symmetric boundary conditions are used.