• 제목/요약/키워드: Position Analysis

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PMSM 적응 센서리스 제어기의 속도/위치 추정기의 특성 분석 (Analysis of characteristics of position/speed estimator of an adaptive sensorless controller for PMSM)

  • 이진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2015년도 전력전자학술대회 논문집
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    • pp.503-504
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    • 2015
  • This paper deals with the analysis of characteristics of position and speed estimator of an adaptive sensorless control algorithm for PMSM drives. The analysis shows that the back emf constant variation results in the position estimation error, but does not the speed estimation error. The simulation and experimental results are shown to verify the analysis result and the usefulness of the back emf constant estimator.

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Comparative Analysis of the Serratus Anterior Muscle Activity When Right and Left Knee Lift during Quadruped Position on Push Up Plus

  • Nam, KiSeok;Kim, JiWoong;Park, JiWon
    • The Journal of Korean Physical Therapy
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    • 제32권1호
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    • pp.58-63
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    • 2020
  • Purpose: This study examined the effects of the right or left knee lift during push up plus in the quadruped position on the serratus anterior (SA) muscle activity. Methods: Twenty-one subjects (male 11, female 10) performed the quadruped position on push up plus. The muscle activities of the lower trapezius (LT), SA, and upper trapezius (UT) were measured by surface electromyography. Repeated measurements of one-way ANOVA were performed for statistical analysis of the data, and the criterion for statistical significance was set to p<0.05 and comparative analysis of the UT and SA ratio using a Paired t-test. Results: The right SA increased the muscle activity of the right knee lift during quadruped position push up plus (p<0.05). In particular, the right SA muscle activity was higher than the left. In addition, comparative analysis of the UT and SA ratio to the right knee lift during quadruped position push up plus was performed (p<0.05). The right was found to be a significant statistic compared to the left, but the left SA increased the muscle activity of the left knee lift during quadruped position push up plus (p<0.05). The left SA muscle activity was higher than right. In addition, comparative analysis of UT and SA ratio to the left knee lift during quadruped position push up plus was performed (p<0.05). The left was found to be a significance statistic than the right. In addition, the interaction effect between the groups showed significant differences (p<0.05). Conclusion: Knee lift during push up plus is recommended for the selective activation of a research exercise protocol of one side of the serratus anterior.

하악전돌증 환자의 악교정 수술후 하악과두의 위치변화에 대한 연구 (A CEPHALOMETRIC AND PANORAMIC ANALYSIS OF THE CHANGES OF THE CONDYLAR POSITION AFTER ORTHOGNATHIC SURGERY)

  • 강영기;김종렬;양동규
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제22권4호
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    • pp.411-419
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    • 2000
  • Purpose: This study was aimed at analysis of the changes in the condyle position in subjects with mandibular setback osteotomies Method: Twenty patients were evaluated retrospectively for their changes in the condyle position who underwent surgical mandibular setback using bilateral sagittal split osteotomies with a manual condyle repositioning technique and rigid fixation. The cephalometric and panoramic analysis was performed preoperatively, 1 week, 6 months, and 1 year postoperatively. And postoperative noise, temporomandibular joint pain, and mouth opening were clinically examined 2 months, 4 months, 6 months, 8 months, 10 months, and 12 months postoperatively. Result: The condyles rotated posteriorly and laterally immediately after surgery, and they returned to the preoperative position during follow-up period but it is not significant. The statistical analysis (Paired t-test) showed no significant effects in postsurgical stability. The changes in the condyle position didn't have a significant harmful influence on temporomandibular joint disorder. Conclusion: A careful surgical mandibular setback using manual condyle repositioning and fixation technique will move condyle minimally and that will decrease the relapse and temporomandibular joint disorder.

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구와 원환체를 이용한 에어백의 모델링 및 비정상위치시의 승객 거동 해석 (A New Airbag Modeling Using a Sphere and a Torus and the Occupant Analysis in the Out-of-position)

  • 임재문;김창환;박경진
    • 한국자동차공학회논문집
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    • 제4권1호
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    • pp.96-109
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    • 1996
  • The airbag system is known to be extremely efficient for the protection in an automobile crash. The performance of the airbag system is evaluated by real tests. However, the test is very difficult and expensive. Therefore, the computational simulations are carried out with low cost. The airbag analysis is included in the anlysis of the full-car crashworthiness. The behavior of the airbag can be predicted by a thermodynamic analysis. The contact force between the occupant and the airbag is calculated from the contact volume and the pressure in the airbag. The injury rate is evaluated from the contact force and the acceleration of dummies. So far, the contact is defined after the airgag is fully inflated. In many cases, the occupant is seated in the out-of-position and the contact can happen during the inflation process. A new algorithm has been developed for the out-of-position. To describe the inflation process precisely, the airbag is defined by a sphere and a torus. The injury is evaluated for the contact happened at any time. The developed algorithm is coded and interfaced with an existing software in the public domain. The full-car modeling is adopted from the previous study which is tuned for the regular position and real tests. Numerical experimentation have been carried out with a couple of dummies in the out-of-position and the injury processes are analyzed.

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Aspect-Based Sentiment Analysis with Position Embedding Interactive Attention Network

  • Xiang, Yan;Zhang, Jiqun;Zhang, Zhoubin;Yu, Zhengtao;Xian, Yantuan
    • Journal of Information Processing Systems
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    • 제18권5호
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    • pp.614-627
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    • 2022
  • Aspect-based sentiment analysis is to discover the sentiment polarity towards an aspect from user-generated natural language. So far, most of the methods only use the implicit position information of the aspect in the context, instead of directly utilizing the position relationship between the aspect and the sentiment terms. In fact, neighboring words of the aspect terms should be given more attention than other words in the context. This paper studies the influence of different position embedding methods on the sentimental polarities of given aspects, and proposes a position embedding interactive attention network based on a long short-term memory network. Firstly, it uses the position information of the context simultaneously in the input layer and the attention layer. Secondly, it mines the importance of different context words for the aspect with the interactive attention mechanism. Finally, it generates a valid representation of the aspect and the context for sentiment classification. The model which has been posed was evaluated on the datasets of the Semantic Evaluation 2014. Compared with other baseline models, the accuracy of our model increases by about 2% on the restaurant dataset and 1% on the laptop dataset.

다점지지 계류시스템의 정적해석에 대한 연구 (A Study on the Analysis of Multi-let Spread Mooring Systems)

  • 신현경;김덕수
    • 한국해양공학회지
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    • 제9권2호
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    • pp.53-60
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    • 1995
  • A multi-leg spread mooring system for floating offshore structures is important, but the multi-leg static analysis is complicated due to the nonlinear behavior of each line and the effect of current which affects each line differently. The pretensioned position of the multi-leg mooring system obtained from the static equilibrium condition changes into a different position due to external loads and current. In this paper, the new position and the static tension at each line are caculated. The relation between the initial static equilibrium position and the new position due to the external loads is expressed in terms of the Taylor's series expansion. The Runge-Kutta $4^{th}$ method is employed in analyzing the 3-dimensional static cable nonlinear equations.

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반송파 기반 센서리스 운전에서 주입하는 신호의 주파수에 따른 위치 추정 성능 분석 (Analysis on Position Estimation Performance according to Injection Frequency in Carrier-Based Sensorless Operation)

  • 황채은;이영기;설승기
    • 전력전자학회논문지
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    • 제23권2호
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    • pp.139-146
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    • 2018
  • This work puts forward a theoretical analysis on position estimation performance of interior permanent magnet synchronous motor (IPMSM) according to the injection frequency in carrier-based sensorless operation. The effects of spatial harmonics on inductance and voltage distortion due to the nonideal characteristics of IPMSM and inverter are examined as factors influencing the position estimation performance. Furthermore, the position estimation performance is analyzed by calculating the current at the switching instant in several operating conditions. In summary, the half switching frequency injection is more robust to the nonideal characteristics of IPMSM, especially with light load condition. The validity of the analysis is verified by the simulation and experimental results.

영미 및 한국의 사서직제 분석과 시사점 (Analysis and Suggestions of the Librarians Public Servants in USA, UK and Korea)

  • 윤희윤
    • 한국도서관정보학회지
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    • 제36권2호
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    • pp.121-140
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    • 2005
  • 이 연구는 영미 양국과 국내의 공직 및 사서직제를 분석하고 시사점을 적출하는데 목적이 있다. 영미의 사례는 직제의 선진성과 시사점을, 그리고 국내의 직제분석은 그 후진성과 현주소를 파악하는데 유용할 뿐만 아니라 후속 연구과제인 사서직제 개선방안의 핵심논거로 활용될 수 있다. 한국의 사서직제가 문화선진국의 그것을 준용하는 방향으로 개편되기 위해서는 도서관 및 사서직에 내재된 이론적, 현실적 취약성과 한계를 극복하기 위한 논리를 개발해야 한다. 그리고 직제개선은 유연한 사고와 주체적 행위가 정합되어야 그 가능성도 높아진다.

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자율주행용 자계도로의 3차원 해석 및 차량위치검출시스템 (3-Dimensional Analysis of Magnetic Road and Vehicle Position Sensing System for Autonomous Driving)

  • 유영재
    • 한국지능시스템학회논문지
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    • 제15권1호
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    • pp.75-80
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    • 2005
  • 이 논문에서는 지능형 교통시스템에서 자율주행용 자계도로 3차원적으로 해석하여 차량의 위치를 검출하기 위한 시스템에 관하여 다룬다. 특히 자율주행시스템을 구성하는 핵심요소 중 하나인 위치검출시스템의 새로운 방법을 제안한다. 기존의 위치검출시스템은 자계와 차량의 위치 관계를 맵핑하는 원리를 이용한다. 이는 데이터의 저장이 필수적이며 대용량의 메모리를 요구되어 상용화시 고비용의 문제점을 가지고 있다. 이 논문에서는 기존 위치검출시스템이 가지는 문제점을 극복하기 위한 방법으로 신경망을 이용한 위치검출시스템을 제안한다. 그리고 제안한 위치검출시스템을 적용한 자율주행시스템을 설계한다. 설계한 자율주행시스템의 적용 가능성을 파악하기 위하여 자율주행실험을 행하고 이를 분석한다.

POSITION RECOGNITION AND QUALITY EVALUATION OF TOBACCO LEAVES VIA COLOR COMPUTER VISION

  • Lee, C. H.;H. Hwang
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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    • pp.569-577
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    • 2000
  • The position of tobacco leaves is affluence to the quality. To evaluate its quality, sample leaves was collected according to the position of attachment. In Korea, the position was divided into four classes such as high, middle, low and inside positioned leaves. Until now, the grade of standard sample was determined by human expert from korea ginseng and tobacco company. Many research were done by the chemical and spectrum analysis using NIR and computer vision. The grade of tobacco leaves mainly classified into 5 grades according to the attached position and its chemical composition. In high and low positioned leaves shows a low level grade under grade 3. Generally, inside and medium positioned leaf has a high level grade. This is the basic research to develop a real time tobacco leaves grading system combined with portable NIR spectrum analysis system. However, this research just deals with position recognition and grading using the color machine vision. The RGB color information was converted to HSI image format and the sample was all investigated using the bundle of tobacco leaves. Quality grade and position recognition was performed through well known general error back propagation neural network. Finally, the relationship about attached leaf position and its grade was analyzed.

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