• 제목/요약/키워드: Horizontal Position

검색결과 918건 처리시간 0.027초

에지 기반 고속 지평선 검출 알고리즘 (A Fast Horizontal line detection algorithm based on edge information)

  • 나상일;이웅호;서동진;이웅희;정동석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
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    • pp.199-202
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    • 2003
  • In the research for Unmaned Air Vehicles(UAVs), the use of Vision-sensor has been increased. It is possible to calculate the position information of air vehicle by finding a horizontal line. In this paper, we proposed a vision-based algorithm for finding the horizontal line. Experimental results show that the proposed algorithm is faster than an existing algorithm.

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Properties of transient horizontal magnetic fields and their implication to the origin of quiet-Sun magnetism

  • Ishikawa, Ryohko
    • 천문학회보
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    • 제37권1호
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    • pp.84.1-84.1
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    • 2012
  • Recent spectropolarimetric observations with high spatial resolution and high polarization sensitivity have provided us with new insight to better understand the quiet-Sun magnetism. This talk is concerned with the ubiquitous transient horizontal magnetic fields in the quiet-Sun, as revealed by the Solar Optical Telescope (SOT) on board Hinode satellite. Exploiting the SOT data with careful treatment of photon noise, we reveal the enigmatic properties of these horizontal magnetic fields such as lifetime, size, position in terms of granular structure, occurrence rate, three-dimensional structure, total magnetic flux, field strength distribution, relationship with the meso- and super-granulations and so on. Based on these observational consequences, we conjecture that the local dynamo process, which takes place in a relatively shallow layer with the granular size, produces these transient horizontal magnetic fields and that these horizontal magnetic fields contribute to the considerable amount of quiet-Sun magnetic fields. We also estimate the magnetic energy flux carried by these horizontal magnetic fields based on the statistical data, and find that the total magnetic energy is comparable to the total chromospheric and coronal energy loss, implying their important role for the chromospheric heating and dynamism.

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Effect of slice inclination and object position within the field of view on the measurement accuracy of potential implant sites on cone-beam computed tomography

  • Saberi, Bardia Vadiati;Khosravifard, Negar;Nourzadeh, Alireza
    • Imaging Science in Dentistry
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    • 제50권1호
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    • pp.37-43
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    • 2020
  • Purpose: The purpose of this study was to evaluate the accuracy of linear measurements in the horizontal and vertical dimensions based on object position and slice inclination in cone-beam computed tomography (CBCT) images. Materials and Methods: Ten dry sheep hemi-mandibles, each with 4 sites (incisor, canine, premolar, and molar), were evaluated when either centrally or peripherally positioned within the field of view (FOV) with the image slices subjected to either oblique or orthogonal inclinations. Four types of images were created of each region: central/cross-sectional, central/coronal, peripheral/cross-sectional, and peripheral/coronal. The horizontal and vertical dimensions were measured for each region of each image type. Direct measurements of each region were obtained using a digital caliper in both horizontal and vertical dimensions. CBCT and direct measurements were compared using the Bland-Altman plot method. P values <0.05 were considered to indicate statistical significance. Results: The buccolingual dimension of the incisor and premolar areas and the height of the incisor, canine, and molar areas showed statistically significant differences on the peripheral/coronal images compared to the direct measurements (P<0.05). Molar area height in the central/coronal slices also differed significantly from the direct measurements (P<0.05). Cross-sectional images of either the central or peripheral position had no marked difference from the gold-standard values, indicating sufficient accuracy. Conclusion: Peripheral object positioning within the FOV in combination with applying an orthogonal inclination to the slices resulted in significant inaccuracies in the horizontal and vertical measurements. The most undesirable effect was observed in the molar area and the vertical dimension.

플랫폼 다이빙 뒤로서서 앞으로뛰기 1½ 회전동작의 운동학적 분석 (A Kinematics Analysis of Inward 1½ Somersault in Platform dives)

  • 이종희
    • 한국운동역학회지
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    • 제16권1호
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    • pp.139-149
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    • 2006
  • This study is to analyze the kinematic variables of inward $1{\frac{1}{2}}$ somersault in platform diver. For the manner, 3 people form the national diving team in the year 2000were chosen as the subjects and two S-VHS video cameras set in 60frames/sec were used for recording their motions. Coordinated raw positions data through digitizing are smoothing by butter-worth's low-pass filterin method at a cut off frequency 6.0Hz. and the direct linear transformation(DLT) method was employed to obtain 3-D position coordinates. The conclusions were as follows. However, horizontal distance which is the change of the COG, form the point of the jump to the point of Event 3 where the player is out of the board range completely, Subject B showed 105.1cm and 71.1cm of the vertical distance which are shorter horizontal distance and higher vertical distance, thus, took a great advantage of the position to prepare for the entry. Therefore, if a player takes higher position by speeding up the vertical velocity at the moment of the jumping off the board, and stays in the air longer, the player can have more time to show his skill. Because of the use of the characteristics of the inward somersault, keeping the safe distance form the board is important but in order to higher the completeness, it is ideal to keep the horizontal distance little over 100cm. Also, the angles of shoulder and elbow from Event 1 to 4, depending on swing of the arms, motions in the air, getting ready for the entry, showed some difference individual by individual, according to the velocity of the thigh and shank showed much difference while getting ready and take-off, and it's because of the individual's different bending and straightening for horizontal and vertical distance.

은행나무 유식물에 있어서 반응조직의 분화에 대한 해부학적 연구 (Anatomical Studies on the Differentiation of Reaction Tissues in Ginkgo biloba L. Seedling)

  • 강경덕
    • Journal of Plant Biology
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    • 제33권4호
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    • pp.285-292
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    • 1990
  • In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Ginkgo biloba seedling in horizontal position. The righting of the horizontal first internode took place at the middle portion and gradually proceeded to the base during the primary growth. Reaction tissues were formed corresponding to the righting movement in the horizontal first internode. During the transition from primary to secondary growth, compression wood was gradually developed on the lower side only. The anatomical features of compression wood also extended longitudinally to the lower side of the vertical portion where it coincided with the lower side of the horizontal first internode occurs acropetally from basal to apical portion. Eventually, some of the anatomical features of compression wood occurred at the primary growth. And the typical compression wood is gradually established during the secondary growth. On the other hand, the lower side tracheid and ray were longer and higher than those of the upper side in the horizontal first internode. However, difference in the width of ray was not observed between the lower and upper sides.

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MULTI-SENSOR DATA FUSION FOR FUTURE TELEMATICS APPLICATION

  • Kim, Seong-Baek;Lee, Seung-Yong;Choi, Ji-Hoon;Choi, Kyung-Ho;Jang, Byung-Tae
    • Journal of Astronomy and Space Sciences
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    • 제20권4호
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    • pp.359-364
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    • 2003
  • In this paper, we present multi-sensor data fusion for telematics application. Successful telematics can be realized through the integration of navigation and spatial information. The well-determined acquisition of vehicle's position plays a vital role in application service. The development of GPS is used to provide the navigation data, but the performance is limited in areas where poor satellite visibility environment exists. Hence, multi-sensor fusion including IMU (Inertial Measurement Unit), GPS(Global Positioning System), and DMI (Distance Measurement Indicator) is required to provide the vehicle's position to service provider and driver behind the wheel. The multi-sensor fusion is implemented via algorithm based on Kalman filtering technique. Navigation accuracy can be enhanced using this filtering approach. For the verification of fusion approach, land vehicle test was performed and the results were discussed. Results showed that the horizontal position errors were suppressed around 1 meter level accuracy under simulated non-GPS availability environment. Under normal GPS environment, the horizontal position errors were under 40㎝ in curve trajectory and 27㎝ in linear trajectory, which are definitely depending on vehicular dynamics.

Comparison of condylar displacement between three biotypological facial groups by using mounted models and a mandibular position indicator

  • Ponces, Maria Joao;Tavares, Jose Pedro;Lopes, Jorge Dias;Ferreira, Afonso Pinhao
    • 대한치과교정학회지
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    • 제44권6호
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    • pp.312-319
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    • 2014
  • Objective: Facial-type-associated variations in diagnostic features have several implications in orthodontics. For example, in hyperdivergent craniofacial types, growth imbalances are compensated by displacement of the condyle. When diagnosis and treatment planning involves centric relation (CR), detailed knowledge of the condylar position is desirable. The present study aimed to measure condylar displacement (CD) between CR and maximum intercuspation in three facial types of an asymptomatic orthodontic population. Methods: The study was conducted in 108 patients classified into three groups of 36 individuals each (27 women and 9 men; mean age, 20.5 years), based on the following facial patterns: hyperdivergent, hypodivergent, and intermediate. To quantify CD along the horizontal and vertical axes, the condylar position was analyzed using mounted casts on a semi-adjustable articulator and a mandibular position indicator. The Student t-test was used to compare CD between the groups. Results: Vertical displacement was found to be significantly different between the hyperdivergent and hypodivergent groups (p < 0.0002) and between the hyperdivergent and intermediate groups (p < 0.0006). The differences in horizontal displacement were not significant between the groups. In each group, vertical CD was more evident than horizontal displacement was. Conclusions: All facial types, especially the hyperdivergent type, carried a significantly high risk of CD. Therefore, the possibility of CD should be carefully evaluated and considered in the assessment of all orthodontic cases in order to accurately assess jaw relationships and avoid possible misdiagnosis.

건물적용 태양광발전시스템의 국내 지역에 따른 설치각도별 연간 전력생산량 예측에 관한 연구 (Annual energy yield prediction of building added PV system depending on the installation angle and the location in Korea)

  • 김동수;신우철;윤종호
    • KIEAE Journal
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    • 제14권1호
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    • pp.67-74
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    • 2014
  • There have distinctly been no the installation criteria and maintenance management of BIPV systems, although the BIPV market is consistently going on increasing. In addition, consideration of the BIPV generation quantity which has been installed at several diverse places is currently almost behind within region in Korea. Therefore, the main aim of this study is to evaluate the BIPV generation and to be base data of reducing rate depending on regional installation angles using PVpro which was verified by measured data. Various conditions were an angle of inclination and azimuth under six major cities: Seoul, Daejeon, Daegu, Busan, Gwangju, Jeju-si for the BIPV system generation analysis. As the results, Seoul showed the lowest BIPV generation: 1,054kWh/kWp.year, and Jeju-si have 5percent more generation: 1,108.0kWh/kWp.year than Seoul on horizontal plane. Gwangju and Daejeon turned out to have similar generation of result, and Busan showed the highest generation: 1,193.5kWh/kWp.year, which was increased by over 13percent from Seoul on horizontal plane. Another result, decreasing rate of BIPV generation depending on regional included angle indicate that the best position was located on azimuth: $0^{\circ}$(The south side) following the horizontal position(an angle of inclination: $30^{\circ}$). And the direction on a south vertical position(azimuth: $0^{\circ}$, an angle of inclination: $90^{\circ}$) then turned out reducing rate about 40percent compared with the best one. Therefore, these results would be used to identify the installation angle of the BIPV module as an appropriate position.

한국인의 상악중절치 위치설정에 관한 연구 (A STUDY ON THE POSITIONING OF THE MAXILLARY CENTRAL INCISOR IN KOREANS)

  • 허윤석;신상완
    • 대한치과보철학회지
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    • 제33권1호
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    • pp.85-97
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    • 1995
  • The arrangement of anterior artificial teeth is an important factor on the esthetics in the construction of complete denture and prosthesis. During construction of the complete denture the position of maxillary central incisor plays an important role in the arrangements of artificial teeth. The proper position of maxillary central incisor provides natural appearance of anterior teeth and the anterior reference point of occlusal plane. Many methods have been utilized to eatablish the position of the maxillary central incisor in complete denture prosthodontics. However, there has not been provided for the reference for Korean yet. This study was aimed to extablish the position of the maxillary central inciosr in Korean. The horizontal and vertical distance between the maxillary central incisor and incisive papilla in korean were measured. The results were as follows : 1. The mean value of horizontal distance from the maxillary central incisor to the incisive papilla had significant sexual difference, the average distance was 12.648mm (male), 11.385mm(female). 2. The horizontal distance of incisive papilla had sexual difference, the average distance was 6.182mm(male), 5.622mm(female). 3. The vertical distance from the maxillary central incisor to the incisive papilla had not sexual difference, the average distance was 7.21mm. 4. The crown length of maxillary central inciosrs from the distal interdental papilla had not sexual difference, the right central incisor was 6.40mm(mean) and the left central inciosr was 6.43mm(mean). 5. The clinical crown length of the maxillary central incisors had not sexual difference, the right central incisor 10.35mm(mean) and the left central incisor was 10.43mm(mean). 6. The anatomic shapes of incisive papilla were pear(68.4%), oval(16%), triangular(6%), irregular(5%), rectangular(4%), and inverted pear(1%) shape.

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Dual Foot-PDR System Considering Lateral Position Error Characteristics

  • Lee, Jae Hong;Cho, Seong Yun;Park, Chan Gook
    • Journal of Positioning, Navigation, and Timing
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    • 제11권1호
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    • pp.35-44
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    • 2022
  • In this paper, a dual foot (DF)-PDR system is proposed for the fusion of integration (IA)-based PDR systems independently applied on both shoes. The horizontal positions of the two shoes estimated from each PDR system are fused based on a particle filter. The proposed method bounds the position error even if the walking time increases without an additional sensor. The distribution of particles is a non-Gaussian distribution to express the lateral error due to systematic drift. Assuming that the shoe position is the pedestrian position, the multi-modal position distribution can be fused into one using the Gaussian sum. The fused pedestrian position is used as a measurement of each particle filter so that the position error is corrected. As a result, experimental results show that position of pedestrians can be effectively estimated by using only the inertial sensors attached to both shoes.