• Title/Summary/Keyword: Approach Angle

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Computed Tomography (CT) Simulated Fluoroscopy-Guided Transdiscal Approach in Transcrural Celiac Plexus Block

  • Kong, Yu Gyeong;Shin, Jin Woo;Leem, Jeong Gill;Suh, Jeong Hun
    • The Korean Journal of Pain
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    • v.26 no.4
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    • pp.396-400
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    • 2013
  • Conventional transcrural CPB via the "walking off" the vertebra technique may injure vital organs while attempting to proximally spread injectate around the celiac plexus. Therefore, we attempted the CT-simulated fluoroscopy-guided transdiscal approach to carry out transcrural CPB in a safer manner, spreading the injectate more completely and closely within the celiac plexus area. A 54-year-old male patient with pancreatic cancer suffered from severe epigastric pain. The conventional transcrural approach was simulated, but the needle pathway was impeded by the kidney on the right side and by the aorta on the left side. After simulating the transdiscal pathway through the T11-12 intervertebral disc, we predetermined the optimal insertion point (3.6 cm from the midline), insertion angle (18 degrees), and advancement plane, as well as the proper depth. With the transdiscal approach, we successfully performed transcrural CPB within a narrow angle, and the bilateral approach was not necessary as we were able to achieve the bilateral spread of the injectate with the single approach.

Recognition of Partial Discharge Patterns using Classifiers and the Neural Network (신경회로망과 Classifier를 이용한 부분방전패턴의 인식)

  • 이준호;이진우
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1999.11a
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    • pp.132-135
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    • 1999
  • In this work, two approaches were proposed for the recognition of partial discharge patterns. The first approach was neural network with backpropagation algorithm, and the second approach was angle calculation between two operator vectors. PD signal were detected using three electrode systems; IEC(b), needle-plane and CIGRE method II electrode system. Both of neural network and angle comparison method showed good recognition performance for the patte군 similar to the trained patterns. And the number of operators to be used had a great influence on the recognition performance to the untrained patterns.

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Kill Probability Analysis Based on the Relation between Final Angle of Attack and Impact Angle of a Guided Anti-tank Missile (대전차유도무기의 종말 받음각 및 입사각의 상관관계에 의한 표적 파괴율 분석)

  • Jeong, Dong-Gil
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.4
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    • pp.520-527
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    • 2010
  • The kill probability of a missile depends on guidance error, warhead performance, and etc. In this paper, we analyzed the kill probability of anti-tank missile in a new approach. Under the condition that the missile hit the target, we studied the effect of angle of attack and impact angle. High impact angle increase the probability that the missile hits the upper armour which is relatively weaker, while high angle of attack at the impact instant decreases the effectiveness of the jet induced by the warhead. We proposed a way to increase the capability of penetration by analyzing the interrelation between impact angle and angle of attack.

A Study on the Multi-Laser Image Tracking Method using the Latest Approach Angle (최근접 각도를 이용한 복수 레이저 영상 추적 방법 연구)

  • Jo, Jin-Pyo;Ko, Ho-Jeong;Kim, Jeong-Ho
    • Journal of Internet of Things and Convergence
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    • v.6 no.2
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    • pp.37-43
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    • 2020
  • The paper proposed the method of calculating the latest approach angle that can reliably recognize multiple laser images even with the change in separation distance between screen and laser launch device. This method recognizes the angle of the laser pattern angle by using the distance of the laser pattern angle, and the angle extraction of the laser detects the laser image from the acquired image using the labeling algorithm, and performs the huff conversion to extract the angle of the straight line. The distance of the reference angle and angle of the laser image extracted using Euclidean distance among similarity scales is calculated, and the furnace is recognized using the calculated distance result value. Experiments with changing the separation distance to "200 cm to 400 cm" showed 100% recognition of individual strands at all separation distances. The experiment confirmed the reliability of the proposed method.

Indoor Mobile Robot Heading Detection Using MEMS Gyro North Finding Approach (MEMS Gyro North Finding 방법을 이용한 실내 이동로봇의 전방향 탐지)

  • Wei, Yuan-Long;Lee, Min-Cheol;Kim, Chi-Yen
    • The Journal of Korea Robotics Society
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    • v.6 no.4
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    • pp.334-343
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    • 2011
  • This paper presents a new approach for mobile robot heading detection using MEMS Gyro north finding method in the indoor environment. Based on this, the robot heading angle measurement scheme is proposed; improved north finding theory and algorithm are also explained. Several approaches are applied to confirm system's precision and effectiveness. In order to find out the heading angle, a single axis MEMS gyroscope to sense the angle between the robot heading direction and the north is used. To reach enough estimation accuracy and reduce detection time, the least square method (LSM) for the signal fitting and parameter estimation is applied. Through a turn-table, we setup a carouseling system to decrease the substantial bias effect on gyroscope's heading angle. For the evaluation of the proposed method, this system is implemented to the Pioneer robot platform. The performance and heading error are analyzed after the test. From the simulation and experimental results, system's accuracy, usefulness and adaptability are shown.

The Third Critical Angle in Reflection of Elastic Waves in Fiber-reinforced Composites (섬유강화 복합재료 내 탄성파 반사현상의 제3임계각)

  • Yim, Hyun-June;Baek, Eun-Sol
    • Composites Research
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    • v.20 no.1
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    • pp.15-22
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    • 2007
  • As a fundamental approach to studying elastic wave behaviors in fiber-reinforced composites, this paper introduces the analytical method to predict the modes, directions, and amplitudes of all reflected waves that are generated by free-surface reflection in fiber-reinforced composites. The paper also explores a new phenomenon where a reflected wave that is predicted to exist in accordance with the slowness surface may disappear. This may occur when the angle of incidence of a quasi-shear wave exceeds a newly defined critical angle, named the third critical angle. It is hoped that the analytical approach introduced in this paper will provide an easy-to-follow guideline for researchers in the relevant area such as ultrasonic nondestructive testing.

Kinematic Analyses of Women's Pole Vault in IAAF World Championships, Daegu 2011 (2011 대구 세계육상선수권대회 여자 장대높이뛰기경기 기술의 운동학적 분석)

  • Choi, Kyoo-Jeong;Yi, Kyung-Ok;Kim, Nam-Hee;Kang, Ji-Eun;Kim, Hye-Lim
    • Korean Journal of Applied Biomechanics
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    • v.21 no.5
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    • pp.561-571
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    • 2011
  • The purpose of this study was to perform the kinematic analyses of the women's pole vault skills in IAAF World Championships Daegu 2011. Subjects were the 1st through 8th place finishers in the pole vault. The kinematic analyses were divided into four phases: two dimensional run up analysis, and three dimensional analyses for the remaining plant, swing up, and extension phases. Run-up variables consisted of run up distance, number of steps, average step length, ratio of step length to height, average velocity at the final 5~10 m, approach position. Three variables were analyzed during plant: pole angle, center of gravity (COG) velocity, and COG takeoff angle. Swing up phase variables included: pole flection angle, COG velocity (horizontal, vertical, resultant), COG trajectory and bar approach angle of COG. Compared to the 2009 World Championships in Berlin, the average vault height increased, while run up velocity and approach position were almost unchanged. However, horizontal velocity during the last two steps of the final approach decreased noticeably compared to speeds from 1990. These results reflect the change in both technique and physical fitness in pole vaulters. During extension, the peak height of COG surpassed the clearance height by an average of 0.11m. These specific results can help coaches and athletes modify training and improve performance.

Design of Path Tracking Controller for Underactuated Autonomous Underwater Vehicle Using Approach Angle Concept (접근 각도 개념을 이용한 과소 작동기 무인 잠수정의 경로 추적 제어기 설계)

  • Kim, Kyoung-Joo;Choi, Yoon-Ho;Park, Jin-Bae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.2
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    • pp.225-231
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    • 2012
  • In this paper, we propose a method for designing the path tracking controller using an approach angle concept for an underactuated autonomous underwater vehicle (AUV). The AUV is controlled by the surge speed and yaw rate: there is no side thruster. To solve this underactuated AUV problem in the path tracking, we introduce an approach angle concept which makes the AUV converge to the reference path. And we design the path tracking controller using the proposed approach angle. To design the path tracking controller, we obtain the new vehicle's error dynamics in the body-fixed frame, and then design the path tracking controller based on Lypunov direct method. Finally, some simulation results demonstrate the effectiveness of the proposed controller.

Transbuccal versus transoral approach for management of mandibular angle fractures: a prospective, clinical and radiographic study

  • Khandeparker, Purva Vijay Sinai;Dhupar, Vikas;Khandeparker, Rakshit Vijay Sinai;Jain, Hunny;Savant, Kiran;Berwal, Vikas
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.42 no.3
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    • pp.144-150
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    • 2016
  • Objectives: We compared the transbuccal and transoral approaches in the management of mandibular angle fractures. Materials and Methods: Sixty patients with mandibular angle fractures were randomly divided into two equal groups (A, transoral approach; group B, transbuccal approach) who received fracture reduction using a single 2.5 mm 4 holed miniplate with a bar using either of the two approaches. Intraoperatively, the surgical time and the ease of surgical assess for fixation were noted. Patients were followed at 1 week, 3 months, and 6 months postoperatively and evaluated clinically for post-surgical complications like scarring, infection, postoperative occlusal discrepancy, malunion, and non-union. Radiographically, the interpretation of fracture reduction was also performed by studying the fracture gap following reduction using orthopantomogram tracing. The data was tabulated and subjected to statistical analysis. A P -value less than 0.05 was considered significant. Results: No significant difference was seen between the two groups for variables like surgical time and ease of fixation. Radiographic interpretation of fracture reduction revealed statistical significance for group B from points B to D as compared to group A. No cases of malunion/non-union were noted. A single case of hypertrophic scar formation was noted in group B at 6 months postsurgery. Infection was noted in 2 patients in group B compared to 6 patients in group A. There was significantly more occlusal discrepancy in group A compared to group B at 1 week postoperatively, but no long standing discrepancy was noted in either group at the 6 months follow-up. Conclusion: The transbuccal approach was superior to the transoral approach with regard to radiographic reduction of the fracture gap, inconspicuous external scarring, and fewer postoperative complications. We preferred the transbuccal approach due to ease of use, minimal requirement for plate bending, and facilitation of plate placement in the neutral mid-point area of the mandible.

Determination of inclination of strut and shear strength using variable angle truss model for shear-critical RC beams

  • Li, Bing;Tran, Cao Thanh Ngoc
    • Structural Engineering and Mechanics
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    • v.41 no.4
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    • pp.459-477
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    • 2012
  • This paper attempts to determine the inclination of the compression strut within variable angle truss models for RC beams loaded in shear-flexure through a proposed semi-analytical approach. A truss unit is used to analyze a reinforced concrete beam, by the principle of virtual work under the truss analogy. The inclination of the compression strut is then theoretically derived. The concrete contribution is addressed by utilizing the compatibility condition within each truss unit. Comparisons are made between the predicted and published experimental results of the seventy one RC beams with respect to the shear strength and the inclined angle of the compression strut at this state to investigate the adequacy of the proposed semi-analytical approach.