• Journal of Communications and Networks
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• v.17 no.4
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• pp.428-439
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• 2015

In this study, we present an approach for reducing the information inaccuracy of existing star aggregation based on bypass links when there are multi-constraint QoS parameters in asymmetric networks. In our approach, bypass links with low similarity are selected. Links that are not chosen as bypass links are included in each group depending on the star's link characteristics. Moreover, each link group is aggregated differently according to the similarity of the links that make up the group. The selection of a bypass link by using link similarity reduces the existing time complexity of O($N^3$) to O(N) by virtue of the simplification of the selection process. In addition, the adaptive integration according to the characteristics of the links in each group is designed to reduce the information inaccuracy caused by static aggregation. Simulation results show that the proposed method maintains low information distortion; specifically, it is 3.8 times lower than that of the existing method, even when the number of nodes in a network increases.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.25 no.2
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• pp.90-95
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• 2014

Background and Objectives : Arytenoid adduction procedure is one of the main surgical options addressed for the correction of glottal incompetence in patients with unilateral vocal cord paralysis. Traditionally, a midline approach is used for identifying and suturing around the muscular process, which often needs over-traction of the thyroid cartilage and results in patient's discomfort as well as surgeon's distress. The authors investigated the advantage of a modified procedure, lateral approach, in which the arytenoid cartilage is exposed through the space between strap muscles and sternocleidomastoid muscle. Materials and Methods : Retrospective chart review was performed for 66 patients who received arytenoid adduction surgery at Samsung Medical Center, between the year 1997 and 2014. Operation time, types of anesthesia, voice outcomes and complications were compared between the midline (n=22) and the lateral (n=44) approach group. Results : Operation time was shorter in the lateral approach group ($125{\pm}24min$) than in the midline group ($144{\pm}24min$). Arytenoid adduction was proceeded under local anesthesia in 66% (n=29/44) and 14% (n=3/22) of patients with lateral and midline approach group, respectively. Voice outcomes and complication rates were comparable between the two groups. Injection laryngoplasty in conjunction with arytenoid adduction resulted in more favorable voice outcomes. Conclusion : A lateral approach for the arytenoid adduction procedure showed comparable voice outcomes and similar complication rates with those of a midline approach. However, lateral approach provided less discomfort to the patients and less distress to a surgeon, and therefore, shorter operation time was needed and local anesthesia could be more frequently applied for this modified procedure.

• Kyungpook Mathematical Journal
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• v.59 no.1
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• pp.23-34
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• 2019

In this paper, we first define generalizations of Pell and Pell-Lucas sequences by the recurrence relations $$p_n=2ap_{n-1}+(b-a^2)p_{n-2}\;and\;q_n=2aq_{n-1}+(b-a^2)q_{n-2}$$ with initial conditions $p_0=0$, $p_1=1$, and $p_0=2$, $p_1=2a$, respectively. We give generating functions and Binet's formulas for these sequences. Also, we obtain some identities of these sequences.

• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.1103-1113
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• 2009

We know that the first digits sequence of fibonacci numbers obey Benford's law. For the sequence in which the first two numbers are the arbitrary integers and the recurrence relation $a_{n+2}=a_{n+1}+a_n$ is satisfied, we can find that the first digits sequence of this sequence obey Benford's law. Also, we can find the stucture of the first digits sequence of this sequence with the exploratory data analysis tools.

• The KIPS Transactions:PartC
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• v.14C no.4
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• pp.383-388
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• 2007

In this paper, we propose a new signal frame structure based on Alamouti code that can maintain the same performance as Alamouti code and increase spectral efficiency. The proposed signal frame structure can increase spectrum efficiency to approach 1(bit/s/Hz) since it can process n bit data during (n+1) time slot. In order to verify two performances, we derive closed form BER via mathematical approach, and compare with the simulation result in Rayleigh fading plus AWGN channel. Then we find that the two performances are exactly same.

• Bulletin of the Korean Mathematical Society
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• v.50 no.1
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• pp.97-103
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• 2013

As a suitable application of the well known generalized maximum principle of Omori-Yau, we obtain rigidity results concerning to a complete hypersurface immersed with bounded mean curvature in the $(n+1)$-dimensional hyperbolic space $\mathbb{H}^{n+1}$. In our approach, we explore the existence of a natural duality between $\mathbb{H}^{n+1}$ and the half $\mathcal{H}^{n+1}$ of the de Sitter space $\mathbb{S}_1^{n+1}$, which models the so-called steady state space.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.445-445
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• 2000

This paper proposes the MIMO indirect adaptive fuzzy controller to control the two-link manipulators. The input-output linearization technique, equivalent control input plus integral term, augmented error model and recursive least square adaptive law are used fer the controller. The linear type of fuzzifier-defuzzifier fuzzy logic system used for nonlinear function makes easy to farm the error model and able to follow the adaptive system approach. Such that control approach, the control system is not required joint speed and accerelation measurement and easy to implement and tune. The simulation results showed that the proposed controller has good control performance, stability, very small tracking error, decoupling, fast convergence, robust to parameter variation and load.

• The Korean Journal of Applied Statistics
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• v.5 no.1
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• pp.9-17
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• 1992

In this paper we give a Bayesian approach to problems of estimation for the ratio in finite populations. Adopting the Ericson's superpopulatin approach in which the finite population of size N is viewed as arising form a random sample of N units from some superpopulation. We derive the exact posterior of the ratio under the noninformative prior on superpopulation parameters. Based on our results we compute an exact Bayesian confidence interval and compare this with the existing methods.

• Honam Mathematical Journal
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• v.27 no.1
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• pp.115-129
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• 2005

In this paper, we give a digital graph-theoretical approach of the study of digital images with relation to a simplicial complex. Thus, a digital graph $G_k$ with some k-adjacency in ${\mathbb{Z}}^n$ can be recognized by the simplicial complex spanned by $G_k$. Moreover, we demonstrate that a graphically $(k_0,\;k_1)$-continuous map $f:G_{k_0}{\subset}{\mathbb{Z}}^{n_0}{\rightarrow}G_{k_1}{\subset}{\mathbb{Z}}^{n_1}$ can be converted into the simplicial map $S(f):S(G_{k_0}){\rightarrow}S(G_{k_1})$ with relation to combinatorial topology. Finally, if $G_{k_0}$ is not $(k_0,\;3^{n_0}-1)$-homotopy equivalent to $SC^{n_0,4}_{3^{n_0}-1}$, a graphically $(k_0,\;k_1)$-continuous map (respectively a graphically $(k_0,\;k_1)$-isomorphisim) $f:G_{k_0}{\subset}{\mathbb{Z}}^{n_0}{\rightarrow}G_{k_1}{\subset}{\mathbb{Z}^{n_1}$ induces the group homomorphism (respectively the group isomorphisim) $S(f)_*:{\pi}_1(S(G_{k_0}),\;v_0){\rightarrow}{\pi}_1(S(G_{k_1}),\;f(v_0))$ in algebraic topology.

• Journal of Korean Foot and Ankle Society
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• v.21 no.4
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• pp.139-143
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• 2017

Purpose: Osteochondral lesion of the talus (OLT) has traditionally been treated using an autologous osteochondral graft via the medial malleolar approach. Here, we compare the traditional method with the anterior arthrotomy approach. Materials and Methods: Between January 2005 and June 2015, 24 cases of patients who received autologus osteochondral graft for OLT and with at least 2 years of follow-up were evaluated. They were divided into two groups; one group receiving autologous osteochondral graft via the medial malleolar osteotomy approach (group 1, n=9) and another group via the anterior arthrotomy approach (group 2, n=15). The clinical outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) score. Results: In all cases, the size of the subchondral cyst of the talus decreased, if not disappeared on the final follow-up radiograph. All osteochondral grafts were united. The mean AOFAS score increased from 61.5 preoperatively to 84.9 at the final follow-up. The mean AOFAS score of group 1 increased from 60.3 preoperatively to 78.0 (p=0.007) at the final follow-up, and the mean AOFAS score of group 2 also increased from 62.2 to 89.1 (p=0.006). The AOFAS score was statistically better in group 2 than in group 1 (p=0.034) at the final follow-up. Conclusion: Autologous osteochondral graft of the OLT yields satisfactory radiologic and clinical outcomes. Especially, better clinical outcome was observed in the group using the anterior arthrotomy approach (group 2) than in the group using the medial malleolar osteotomy approach (group 1).