• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.78-80
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• 1994

Conventional methods for root finding of the algebraic equations are intrinsically synthetic division methods, i.e., which are the factorization in forms of $f(x)=(x-x_i)Q(x)$. So existing methods have some demerits such as deflation and root-polishing procedures. To overcome these defects a new powerful algorithm, namely circular arithmetic algorithm(CSM), was introduced and has been investigated about its fascinating properties. In this paper, we will propose a simple and effective method of getting the initial guesses for the roots of the equation. With this method the CSM can me all the root of equation with great efficiency.

• Imaging Science in Dentistry
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• 제52권2호
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• pp.165-170
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• 2022

Purpose: This report presents a case of an unusual and rare presentation of Stafne bone defect (SBD) with apical resorption extending from the lower right lateral incisor to the right first premolar. A systematic search of the current literature on cases where SBD affected the adjacent teeth was conducted. Materials and Methods: From 259 identified articles, 114 studies were examined, containing 12 individuals with a mean age of 41.58 years. Ten cases in the anterior mandible and 2 in the posterior mandible were found. Results: The results of SBD varied from apical blunting to severe root resorption, and some cases showed close apical contact with the lesion or involvement of the root without any effect. Conclusion: SBD is an unusual incidental finding in the anterior region of the mandible, and unexpected behavior of the lesion, such as root resorption, must be considered.

• Journal of Periodontal and Implant Science
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• 제23권3호
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• pp.647-658
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• 1993

The purpose of this study is to examine the influence of 5% tetracycline(Tc) gel on healing of gingival tissue and change of diseased root surface when used with nonsurgical procedure. 7 patients with advanced periodontitis were received thorough scaling and root planning, followed by saline irrigation on 10 randomly selected control teeth and Tc gel application for 5 minutes with specifically designed plastic instrument of 10 test teeth in contralateral side. At 0, 1, 7, 14, and 21 days after treatment, biopsy and extraction were carried out. At day 7, Tc group showed decreased inflammation and delayed proliferation of pocket epithelium in comparison with control group which was continued for all experimental days. Scanning electron microscopic finding revealed demineralized and cleaned root surface with exposed dentinal tubules in Tc gel group. In the present study, clinically successful result is expected with combined use of nonsurgical periodontal therapy and intrapocket application of Tc gel.

• Journal of Korean Neurosurgical Society
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• 제46권1호
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• pp.11-15
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• 2009

Objective: Two findings easily found at coronal source images of MR myelography (MRM) were evaluated : dorsal root ganglion (DRG) swelling and running course abnormality (RCA) of L5 exiting root at foramen or extraforamen. We tried to find the sensitivity of each finding when root was compressed. Methods: From 2004 July to 2006, one hundred and ten patients underwent one side paraspinal decompression for their L5 root foraminal or extraforaminal compression at L5-S1 level. All kinds of conservative treatments failed to improve leg symptom for several months. Before surgery, MRI, CT and MRM were done. Retrospective radiologic analysis for their preoperative MRM coronal source images was done to specify root compression sites and L5 root morphologic changes. Results: DRG swelling was found in 66 (60%) of 110 patients. DRG swelling has statistically valuable meaning in foraminal root compression (chi-square test, p<0.0001). Seventy-two (66%) in 110 patients showed abnormal alteration of running course. Abnormal running course has statistically valuable meaning in foraminal or extraforaminal root compression (chi-square test, p<0.0001). Conclusion: Three-dimensional MRM provides precise thin sliced coronal images which are most close to real operative views. DRG swelling and running course abnormality of L5 exiting root are two useful findings in diagnosing L5 root compression at L5-S1 foramen or extraforamen. MRM is thought to provide additional diagnostic accuracy expecially in L5-S1 foraminal and extraforaminal area.

• 전기학회논문지
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• 제67권2호
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• pp.277-284
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• 2018

In this paper, a new numerical method of finding the roots of a nonlinear system is proposed, which extends the conventional fixed point iterative method by relaxing the constraints on it. The proposed method determines the real valued roots and expands the convergence region by relaxing the constraints on the conventional fixed point iterative method, which transforms the diverging root searching iterations into the converging iterations by employing the metric induced by the geometrical characteristics of a polynomial. A metric is set to measure the distance between a point of a real-valued function and its corresponding image point of its inverse function. The proposed scheme provides the convenience in finding not only the real roots of polynomials but also the roots of the nonlinear systems in the various application areas of science and engineering.

• Restorative Dentistry and Endodontics
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• 제44권2호
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• pp.16.1-16.12
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• 2019

Objectives: The upper molars generally have three roots; therefore, different combinations of fusion can occur, increasing the possibility of finding more complex root canal systems. The purpose of this study was to evaluate the prevalence and characterization of fused roots in first and second maxillary molars using cone-beam computed tomography (CBCT) in a Colombian population. Materials and Methods: A total of 1274 teeth were evaluated, of which 534 were maxillary first molars and 740 were maxillary second molars. Axial sections were made at the cervical, middle, and apical levels to determine the prevalence of root fusion and the types of fusion. Results: Overall, 43% of the molars (n = 551) presented some type of fused root. Root fusion was present in 23.4% of the maxillary first molars. The most frequent type of fused root was type 3 (distobuccal-palatal; DB-P) (58.9%). Root fusion was observed in 57.6% of the maxillary second molars, and the most prevalent type of fused root was type 6 (cone-shaped) (45.2%). Of the maxillary molars, 12.5% were classified as C-shaped. Conclusion: Within the limitations of this study, there was a high prevalence of fused roots in maxillary molars in the Colombian population, mainly in the maxillary second molars. In first molars, the most common type of fused root was type 3 (DB-P) and in second molars, the most common type was type 6 (cone-shaped). Additionally, molars with root fusion presented variation at different levels of the radicular portion, with implications for treatment quality.

• The Korean Journal of Pain
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• 제13권2호
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• pp.247-250
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• 2000

Recently, some authors reported that discogenic low back pain should be regarded as a referred pain in respect of neural pathway. The afferent pathways of discogenic low back pain is transmitted mainly by sympathetic afferent fibres from the sinuvertebral nerves in the second lumbar nerve root. This pain arises from the lumbar intervertebral discs, and it had been transmitted mainly through the sympathetic afferent fibres contained in the second lumbar spinal nerve root. Second lumbar dermatome corresponds to the low back area. We experienced a case of low back pain which could not be controlled by conventional therapy and progressed wax and wane. The CT finding showed bulging disc between $L_4$ and $L_5$ and spinal stenosis in $L_4$ area. And epiduroscopic feature showed severe adhesion in $L_4$, $L_5$ and $S_1$. After we blocked $L_2$ root, pain score decreased 10 to 2. Therefore, the $L_2$ root block may be a useful diagnostic procedure as well as provide therapeutic value.

• 한국컴퓨터정보학회논문지
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• 제21권5호
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• pp.49-56
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• 2016

Increasing Internet traffic and forwarding table size need high performance IP address lookup engine which is a crucial function of routers. For finding the longest matching prefix, trie-based or its variant schemes have been widely researched in software-based IP lookup. As a software router, we enhance the IP address lookup engine using GPU which is a device widely used in high performance applications. We propose a data structure for multibit trie to exploit GPU hardware efficiently. Also, we devise a novel scheme that the root subtrie is loaded on Shared Memory which is specialized for fast access in GPU. Since the root subtrie is accessed on every IP address lookup, its fast access improves the lookup performance. By means of the performance evaluation, our implemented GPU-based lookup engine shows 17~23 times better performance than CPU-based engine. Also, the fast access technique for the root subtrie gives 10% more improvement.

• 대한기계학회논문집
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• 제18권12호
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• pp.3159-3174
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• 1994

A simple octree encoding algorithm based on a tetrahedron root has been developed to be used for fully automatic generation of three dimensional finite element meshes. This algorithm starts octree decomposition from a tetrahedron root node instead of a hexahedron root node so that the terminal mode has the same topology as the final tetrahedral mesh. As a result, the terminal octant can be used as a tetrahedral finite element without transforming its topology. In this part(I) of the thesis, an efficient algorithm for the tetrahedron-based octree is proposed. For this development, the following problems have been solved, : (1) an efficient data structure for storing the octree and finite elements, (2) an encoding scheme of a tetrahedral octree, (3) a neighbor finding technique for the tetrahedron-based octree.

• 한국항공우주학회지
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• 제30권4호
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• pp.92-98
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• 2002

본 논문에서는 반능동 레이더 미사일에 대해 다양한 발사 조건과 성능 제한 조건, 표적기의 기동 등을 고려하여 최대 발사 거리 및 F-pole을 산출하고 이를 비교 분석하였다. 또한, Head-On 대치 시 수행되는 일반적 회피 기동에 대해서도 고찰하였다. 표적기와 공격기, 미사일은 질점으로 모델링하였으며 미사일은 공력 성능, 기하학적인 형상, 성능 제한사항, 탐색 레이더의 짐발 제한 등 다양한 고려 요소들을 포함시켜 기존의 연구보다 현실적인 시뮬레이션을 수행하였다. 최대 사거리는 표적기와 미사일의 운동, 미사일의 성능 제한 조건들을 만족하면서 미사일이 추적할 수 있는 최대의 시간에 명중될 수 있는 거리로서 Root Finding Method를 사용하여 산출하였다. F-pole은 명중시 공격기와 표적기와의 거리로서 공격기는 표적기에 대해 추적 유도 방식을 수행하도록 지정하여 그 거리를 산출하였다.