• 제목/요약/키워드: deviation

검색결과 9,444건 처리시간 0.039초

Three-dimensional analysis of the outcome of different scanning strategies in virtual interocclusal registration

  • Jiansong, Mei;Liya, Ma;Jiarui, Chao;Fei, Liu;Jiefei, Shen
    • The Journal of Advanced Prosthodontics
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    • 제14권6호
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    • pp.369-378
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    • 2022
  • PURPOSE. The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS. Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies. Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS. For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION. Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations.

턱관절균형의학에서 편차발생현상의 신경과학 및 재료역학적 해석과 일반화 (Interpretation and Generalization by Neuroscience and Material Mechanics on Deviation in Temporomandibular Joint Balancing Medicine)

  • 지규용
    • 턱관절균형의학회지
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    • 제12권1호
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    • pp.1-6
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    • 2022
  • Objectives: For the deviation phenomenon occurring during the treatment process in temporo-mandibular balancing medicine (TBM), hypotheses were established regarding the cause and mechanism of formation from the perspective of neuro-science and material mechanics, and a verification method was proposed. Methods: The deviation phenomenon was theoretically analyzed based on the structure theories of material mechanics of the joint and the neurological pain mechanism. Results: Deviation occurs due to temporary yield by the accumulation of heterogeneous stress in the temporo-mandibular joint and the affected joint. Because the joint structures are corresponding with material mechanics showing compressive and tensile properties. The size of the deviation is expressed in terms of strain. The occlusal surface of the teeth is level with the axial joint. Since the magnitude of the deviation has a proportional relationship with the degree of abnormality of the temporo-mandibular joint, the magnitude of the deviation calculated by the balance measurement can be replaced by the strain. The major variables involved in the occurrence of deviations are the strength of joint structures and neurological conditions. Therefore plastic deformation and adaptation occur as a long-term depression of neural circuits is strengthened in different ways at different locations each time in various clinical situations. This is the reason why the sequence of the restoration process while correcting deviations is following reverse order of the accumulation in many layers in the muscular nervous system. Conclusions: From the above results, it can be inferred that the occurrence and correction of the deviations are corresponding with the plastic deformation and neuro-plasticity.

A Comparative of Knee Joint Instability and Muscle Activity Due to Medial or Lateral Deviation of Knee while Lunge Exercise

  • Sijin Lee;Byeong-Jo Min;Jin-A Park;Hyeong-Geun Kim;Doochul Shin
    • Physical Therapy Rehabilitation Science
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    • 제13권2호
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    • pp.163-170
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    • 2024
  • Objective: The purpose of this study was to compare the muscle activity of the vastus lateralis, vastus medialis, rectus femoris, and gluteus medius muscles according to the medial/lateral bias of the knee during lunge exercise. Design: Crossed-control group study Methods: This study recruited 20 healthy men and women in their 20s who were capable of lunge exercise and had no musculoskeletal or neurological abnormalities. All three postures were performed three times each during lunge exercise. In each posture, surface electromyography (EMG) equipment was used to measure muscle activity of the vastus lateralis, vastus medialis, rectus femoris, and gluteus medius during lunge exercise. Results: As a result of comparing lower extremity muscle activity in normal, medial and lateral knee-deviation postures according to lunge exercise, the muscle activity of the vastus medialis was 107.09±13.90% in the normal posture, 79.24±5.26% in the medial- deviation posture and 125.73±14.30% in the lateral- deviation posture, which was a statistically significant difference (p<0.05). However, In the case of the vastus lateralis, rectus femoris and gluteus medius there was no statistically significant difference in muscle activity in the medial and lateral deviation positions(p>0.05). Conclusions: As a result, it was found that the muscle activity of the vastus medialis during lunge exercise significantly increased in the lateral deviation posture compared to the normal and medial deviation postures. In the case of the vastus lateralis, rectus femoris and gluteus medius there was no significant difference in muscle activity for medial and lateral knee deviation.

효율적인 LARGE DEVIATION 방법에 의한 발전 시뮬레이션에 관한 연구 (A STUDY ON THE PROBABILISTIC PRODUCTION COST SIMULATION BY THE EFFICIENT LARGE DEVIATION METHOD)

  • 송길영;차준민;김용하;오광해
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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    • pp.244-246
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    • 1990
  • This paper describes the Large Deviation Method for computing the loss-of-load-probability (L.O.L.P.) index for a generating system. Also, we introduce a rule to prevent the initial value from diverging in Newton-Raphson method which we have to use to determine the value of t. By applying the Large Deviation Method to computing the L.O.L.P. index for some representative reliability test systems, it is verified that the Large Deviation Method is generally very accurate and very fast.

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미소한 비대칭이 존재하는 원판의 진동해석을 위한 유한요소 개발 (Development of a Finite Element for Vibration Analysis of an Annular Plate with Slight Deviation)

  • 김민중;정진태;이장무
    • 소음진동
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    • 제10권2호
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    • pp.361-366
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    • 2000
  • In this paper, a new finite annular plate element is developed, which considers the effects of the slight deviation from a perfect axisymmetry. It is assumed that, when a local deviation is introduced to an axisymmetric plate, the natural modes are separated into the symmetric and asymmetric modes. The proposed method is very efficient because a few elements are demanded and lots of active degrees of freedom are reduced in comparison with commercial numerical analysis programs. In addition, when the deviation is small enough. It is more accurate than the result of using usual plate elements of commercial FEM programs.

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품질비용 발생편차와 품질관리활동 그리고 성과간의 관계:품질성과와 납기성과를 중심으로 (The Relationships among the Degree of Quality Cost Deviation, Quality Management Activities and Performance)

  • 김달곤;김순기;정순여
    • 품질경영학회지
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    • 제31권4호
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    • pp.1-18
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    • 2003
  • Quality is a critical competitive factor in today's environment because of the impact of quality on costs and delivery. Many companies regard quality as a key concept of company strategy in order to achieve the competitive edge. Measuring and reporting quality cost is the first step in quality management program. The supposition of quality cost model is that investment in prevention activities will bring rewards from reduced failure costs, and that further investment in prevention activities will show profits from reduced appraisal costs. In this study, the degree of quality cost deviation is conceptualized. This means a deviation between the ideal and present ranking in the amounts of quality cost categories. This study analysed that the effect of its deviation on quality management activity and performance variables. However, there are no difference in these variables. The major reason is that most of companies are endeavoring for quality management but operating quality cost system unsystematically. The review against a prevention and appraisal activity is necessary.

Asymptotic Properties of Nonlinear Least Absolute Deviation Estimators

  • Kim, Hae-Kyung;Park, Seung-Hoe
    • Journal of the Korean Statistical Society
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    • 제24권1호
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    • pp.127-139
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    • 1995
  • This paper is concerned with the asymptotic properties of the least absolute deviation estimators for nonlinear regression models. The simple and practical sufficient conditions for the strong consistency and the asymptotic normality of the least absolute deviation estimators are given. It is confirmed that the extension of these properties to wide class of regression functions can be established by imposing some condition on the input values. A confidence region based on the least absolute deviation estimators is proposed and some desirable asymptotic properties including the asymptotic relative efficiency also discussed for various error distributions. Some examples are given to illustrate the application of main results.

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