• Title/Summary/Keyword: challenging problems

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Correction of Lip Canting Using Bioabsorbables during Orthognathic Surgery

  • Park, Young-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.36 no.4
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    • pp.178-183
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    • 2014
  • Lip canting is associated with facial asymmetry, and is one of the most challenging problems in surgical correction of facial deformities. The author corrected lip canting using bioabsorbable devices during orthognathic surgery. Soft tissue suspension procedures were performed on four patients with facial asymmetry. Lip lines improved for all patients. Over an observation period of five years, no complications were noted, nor did any late relapse develop. Furthermore, as time past, the effect of the Endotine suspension procedure increased probably due to induction of fibrosis on surrounding soft tissues.

COMPARISON OF METAHEURISTIC ALGORITHMS FOR EXAMINATION TIMETABLING PROBLEM

  • Azimi, Zhara-Naji
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.337-354
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    • 2004
  • SA, TS, GA and ACS are four of the main algorithms for solving challenging problems of intelligent systems. In this paper we consider Examination Timetabling Problem that is a common problem for all universities and institutions of higher education. There are many methods to solve this problem, In this paper we use Simulated Annealing, Tabu Search, Genetic Algorithm and Ant Colony System in their basic frameworks for solving this problem and compare results of them with each other.

Development of Fuzzy Objective Functioin for Establishing the Region Correspondence

  • Soh, Young-sung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.2 no.3
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    • pp.22-28
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    • 1992
  • One of the challenging problems in dynamic scene analysis is the correspondence problem. Points and lines have been two major entities for establishing the correspondence among suxcessive frmes and gave rise to discrete approach to dynamic scene analysis. SOme researchers take continuous approach to analyse the motion. There it is usually assumed that some sort of region correspondence has already been established. In this paper, we propose a method based on fuzzy membership function for solving region correspondence problem.

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Implant Placement Using Various Surgical Techniques: Case Report

  • Lee, Ji-Young;Kim, Young-Kyun
    • Journal of Korean Dental Science
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    • v.3 no.2
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    • pp.50-59
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    • 2010
  • Implant placement is frequently complicated and challenging because of the poor quality and inadequate height of bone. Clinicians should consider various surgical procedures to overcome the problems. We report a case with various surgical procedures used such as inferior alveolar nerve repositioning, sinus bone graft, and autogenous block bone graft using the coronoid process and ramus to overcome severe vertical and horizontal alveolar bone atrophy.

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Analysis of Automatic Machine Learning Solution Trends of Startups

  • Lee, Yo-Seob
    • International Journal of Advanced Culture Technology
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    • v.8 no.2
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    • pp.297-304
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    • 2020
  • Recently, open source automatic machine learning solutions have been applied in many fields. To apply open source automated machine learning to real world problems, you need to write code with expertise in machine learning. Writing code without machine learning knowledge is challenging. To solve this problem, the automatic machine learning solutions provided by startups are made easy to use with a clean user interface. In this paper, we review automatic machine learning solutions of startups.

A field-consistency approach to plate elements

  • Prathap, Gangan
    • Structural Engineering and Mechanics
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    • v.5 no.6
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    • pp.853-865
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    • 1997
  • The design of robust plate and shell elements has been a very challenging area for several decades. The main difficulty has been the shear locking phenomenon in plate elements and the shear and membrane locking phenomena together in the shell elements. Among the various artifices or devices which are used to develop elements free of these problems is the field-consistency approach. In this paper this approach is reviewed, It turns out that not only Mindlin type elements but also elements based on higher-order theories could be developed using the technique.

Online nonparametric Bayesian analysis of parsimonious Gaussian mixture models and scenes clustering

  • Zhou, Ri-Gui;Wang, Wei
    • ETRI Journal
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    • v.43 no.1
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    • pp.74-81
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    • 2021
  • The mixture model is a very powerful and flexible tool in clustering analysis. Based on the Dirichlet process and parsimonious Gaussian distribution, we propose a new nonparametric mixture framework for solving challenging clustering problems. Meanwhile, the inference of the model depends on the efficient online variational Bayesian approach, which enhances the information exchange between the whole and the part to a certain extent and applies to scalable datasets. The experiments on the scene database indicate that the novel clustering framework, when combined with a convolutional neural network for feature extraction, has meaningful advantages over other models.

Renzulli 수학 영재 교수-학습 모형 적용에 관한 연구

  • Nam, Young-Man;Park, Dong-Am
    • East Asian mathematical journal
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    • v.25 no.3
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    • pp.379-397
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    • 2009
  • In this paper we apply to Renzulli's Teaching and Learning models for mathematically gifted students based on the gifted science education center in university. Gifted students were very positive reaction in solving problems creatively using this program, and they were challenging and very confident performing new tasks. They reacted variously in debates with their classmates, in self-initiative studying. So more positive changes are needed for the activities using the gifted learning-teaching program to let each student have full use of his or her possibility and potential.

Autotransplantation of Premolars and Esthetic Rehabilitation in a Traumatized Teenage Patient with Challenging Oral Problems: A Case Report (어려운 구강 문제를 가진 외상당한 청소년 환자의 소구치 자가이식 및 심미적 회복: 증례 보고)

  • Kho, Junhee;Park, Howon;Lee, Juhyun;Seo, Hyunwoo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.47 no.2
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    • pp.213-218
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    • 2020
  • The loosely structured periodontal ligament and low mineralized bone surrounding erupting teeth provide minimal resistance to an extrusive force. The maxillary central incisors are the most frequently avulsed due to trauma. The prognosis of replanted teeth is affected by extra-alveolar period and conditions. Implant-supported restorations are contraindicated in adolescent patients with poor prognosis traumatized teeth. Autotransplantation of premolar to the anterior region provides a viable treatment alternative. This case report describes the autotransplantation of premolars and esthetic rehabilitation in a teenage patient with traumatized incisors, poor oral hygiene, and severe crowding. Comprehensive and long-term treatments were performed to improve complex and challenging oral problems.

Heuristics for Motion Planning Based on Learning in Similar Environments

  • Ogay, Dmitriy;Kim, Eun-Gyung
    • Journal of information and communication convergence engineering
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    • v.12 no.2
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    • pp.116-121
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    • 2014
  • This paper discusses computer-generated heuristics for motion planning. Planning with many degrees of freedom is a challenging task, because the complexity of most planning algorithms grows exponentially with the number of dimensions of the problem. A well-designed heuristic may greatly improve the performance of a planning algorithm in terms of the computation time. However, in recent years, with increasingly challenging high-dimensional planning problems, the design of good heuristics has itself become a complicated task. In this paper, we present an approach to algorithmically develop a heuristic for motion planning, which increases the efficiency of a planner in similar environments. To implement the idea, we generalize modern motion planning algorithms to an extent, where a heuristic is represented as a set of random variables. Distributions of the variables are then analyzed with computer learning methods. The analysis results are then utilized to generate a heuristic. During the experiments, the proposed approach is applied to several planning tasks with different algorithms and is shown to improve performance.