• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.4
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• pp.458-464
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• 2014

This paper proposes the rotor position and rotor speed estimation for an interior permanent magnet synchronous machines (IPMSM) using Unscented Kalman Filter (UKF) in alpha-beta coordinate system. Conventional algorithms using UKF are based on the simple observer model of IPMSM in d-q coordinate system. Rotor acceleration is neglected within the sampling step. An expansion of the observer model in an alpha-beta coordinate system with the consideration of the rotor speed variation provides the improved rotor position and speed estimation. The results show good stability concerning the expansion of observer model for the IPMSM.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1799-1802
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• 2007

In the constructed auto-stereoscopic display system for one observer. 1.stereoscopic images displayed on a special LCD are made on a large concave mirror. 2.The view-zone limiting aperture is set between the projection lens and the concave mirror. 3.The real image of the aperture is made at the observer's eye position by the concave mirror. 4.The observer's eye-position tracking of the view-zone is realized. 5.At same time, stereoscopic image changes automatically according to the eye position of the observer.

• Journal of Mechanical Science and Technology
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• v.17 no.3
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• pp.336-342
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• 2003

Increasing demand on precision machining using computerized numerical control (CNC) machines have necessitated that the tool move not only with the smallest possible position error but also with smoothly varying feedrates in 3-dimensional (3D) space. This paper presents the simultaneous 3D machining process investigated using a retrofitted PC-NC milling machine. To achieve the simultaneous 3-axis motions, a new precision interpolation algorithm for 3D Non Uniform Rational B-Spline (NURBS) curve is proposed. With this accurate and efficient algorithm for the generation of complex 3D shapes, a real-time NURBS interpolator was developed using a PC and the simultaneous 3D machining was accomplished satisfactorily.

• Spatial Information Research
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• v.13 no.2 s.33
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• pp.129-138
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• 2005

In this paper, a 3D position tracking algorithm for a moving objects using a stereo CCD cameras was proposed. This paper purposed the method to extract the coordinates of the moving objects. That is improve the operating and data processing efficiency. We were applied the relative orientation far the stereo CCD cameras and image coordinates extraction in the left and right images after the moving object segmentation. Also, it is decided on 3D position far moving objects using an acquired image coordinates in the left and right images. We were used independent relative orientation to decide the relative location and attitude of the stereo CCD cameras and RGB pixel values to segment the moving objects. To calculate the coordinates of the moving objects by space intersection. And, We conducted the experiment the system and compared the accuracy of the results.

• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.272-277
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• 2010

AR(Augmented Reality) needs medium between real and virtual, world, and recognition techniques are necessary to track an object continuously. Optical tracking using marker is mainly used, but it takes time and is inconvenient to attach marker onto the target objects. Therefore, many researchers try to develop markerless tracking techniques nowaday. In this paper, we extract features and 3D position from 3D objects and suggest realtime tracking based on these features and positions, which do not use just coplanar features and 2D position. We extract features using SURF, get rotation matrix and translation vector of 3D object using POSIT with these features and track the object in real time. If the extracted features are nor enough and it fail to track the object, then new features are extracted and re-matched to recover the tracking. Also, we get rotation in matrix and translation vector of 3D object using POSIT and track the object in real time.

• The Journal of the Acoustical Society of Korea
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• v.19 no.7
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• pp.7-14
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• 2000

In this paper, we propose a near-field target localization algorithm using a bottom-mounted linear sensor amy in a multipath environment. In a multipath environment, the conic angles of a target signals through each path are different, and the position of the target can be estimated using these conic angles and the time difference of these signals. We derive equations on the relation of time-difference of signals and conic angles estimates under the far-field assumption, and estimate the position of target by simultaneously solving these equations. For a certain geometry of a target and the sensor array, there exist cases when the conic angles are very close. In such a case, we estimate the position of the target using an additional 1-D search.

• Animal Systematics, Evolution and Diversity
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• v.36 no.3
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• pp.240-250
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• 2020

Member of the genus Tobrilus Andrássy, 1959, which belongs to Tobrilidae Filipjev, 1918, are known as free-living nematodes in freshwater habitat. This genus was previously unknown from Korea. Five Tobrilus species are here reported for the first time from Korea: Tobrilus aberrans (Schneider, 1925), Tobrilus diversipapillatus (Daday, 1905), Tobrilus gracilis (Bastian, 1865), Tobrilus longus (Leidy, 1851), and Tobrilus wesenbergi (Micoletzky, 1925). Specimens were collected from sediments of the Nakdong River in Korea. Morphological characters and measurements of the specimens generally agree with the original descriptions of Tobrilus species, except for some differences that can be attributed to intraspecific variation among populations(e.g., nerve ring position [% pharynx] and reproductive length). Each species can be distinguished from other members of the genus by specific characters (e.g., cephalic setae length and position, buccal cavity and pocket shape, vulva position, degree of development of reproductive system, and tail length and shape). Here, five species in the genus Tobrilus are fully redescribed and illustrated using optical microscopy images. DNA barcode sequence information (the D2-D3 region of 28S rDNA) is also provided for molecular species identification.

• Journal of Korean Academy of Nursing
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• v.8 no.1
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• pp.139-151
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• 1978

This study is to observe the effects of nursing care according to change of position for comfort during labor and safe delivery of newborn infants and perturbment women. Fifty antepartal primipara with labor pain who were admitted to the delivery room of H University Medical Center from September 1, 1976 to November 15, 1976 (Estimate Delivery Confinement) were selected for this investigation. Among the 50 parturiencys, the experimental group (28 primipara) were placed in 30 degree upright sitting position and the control group (22 primipara) were placed in the supine position. following placement, both groups were observed. The summarized findings of the study were as follows; 1. There was a noticeably significant difference in the duration of the first stage of labor (defined as 4 cm. dilatation of the cervical os with the fetal presenting part engaged to full or 10 cm. dilatation) , between the two groups. For women in the 30 degree upright sitting position, the first stage of labor was close to 33.66 minutes shorter. than for the women in the supine position. (t : 32.79, D.F : 48, p<0.0,i) 2. Although slight differences were observed between the Apgar Scores of the newborn infants of primipara in the two groups, these were not significant. The mean Apgar Score among the newborn infants of primipara in the 30 degree upright sitting position was 9.64 compared with 9.04 for the newborn infants of primipara in the supine position, a difference of 0.6. (x$^2$= 2.44, D.F : 2, p〉0.05) 3. There was a significant difference in the conformability of the perturbment women between the two groups because the shortened duration of the first stage and the high level of comfort score calculated for six factors (body activity, serving bed pan, serving kidney basin, pushing, deep breathing and perturbment women's feelings), that affect nursing care.

• Knowledge Management Research
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• v.10 no.3
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• pp.153-173
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• 2009

Virtual world typically characterized by Second Life (www.secondlife.com) has been successfully drawing a great deal of potential users all around the world. Attention towards 3D avartars has been increasing exponentially especially in the electronic commerce world. 3D avatars have firm position in the virtual world. This study is launched to explore this research void in which trust transference from 3D-avatars-sales representative to customers purchase intention will be especially analyzed on. To perform experiments, a research model was built in a form of path analysis. Two types of 3D avatars were designed and implemented-at-tractive type and professional type. Questionnaire survey was adopted, and empirical analysis results were obtained from the research model. Results reveal that the proposed hypotheses are proven with statistical significance.

• Journal of IKEEE
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• v.26 no.2
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• pp.160-168
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• 2022

In this paper, we propose a 3D mesh reconstruction method from a single image using deep learning and a sphere shape transformation method. The proposed method has the following originality that is different from the existing method. First, the position of the vertex of the sphere is modified to be very similar to the 3D point cloud of an object through a deep learning network, unlike the existing method of building edges or faces by connecting nearby points. Because 3D point cloud is used, less memory is required and faster operation is possible because only addition operation is performed between offset value at the vertices of the sphere. Second, the 3D mesh is reconstructed by covering the surface information of the sphere on the modified vertices. Even when the distance between the points of the 3D point cloud created by correcting the position of the vertices of the sphere is not constant, it already has the face information of the sphere called face information of the sphere, which indicates whether the points are connected or not, thereby preventing simplification or loss of expression. can do. In order to evaluate the objective reliability of the proposed method, the experiment was conducted in the same way as in the comparative papers using the ShapeNet dataset, which is an open standard dataset. As a result, the IoU value of the method proposed in this paper was 0.581, and the chamfer distance value was It was calculated as 0.212. The higher the IoU value and the lower the chamfer distance value, the better the results. Therefore, the efficiency of the 3D mesh reconstruction was demonstrated compared to the methods published in other papers.