• Title/Summary/Keyword: separating point

Search Result 111, Processing Time 0.024 seconds

ACCURATE SYNTHESIS OF SEEDLING SEPARATING-PLANTING MECHANISM OF RICE TRANSPLANTER

  • Hu, Hanxiang;Chen, Dejun;Wang, Changbing;Li, Zhenyong;Wu, Jienian;Xu, Jinda
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 1993.10a
    • /
    • pp.284-290
    • /
    • 1993
  • In order to improve the adaptability of rice transplanter to seeding with different length when transplanting multicropping rice in south China. The seedling separating planting mechanism is resynthesized in the paper. According to the agronomy requirements of seedling's transplanting, optimum motional path of the tip point of planting needle is obtained. by applying the established kinematic model of the separating planting mechanism, the relevant software is compiled. On the basis of the features of the problem, the constrained optimization method is utilized to solve the problem with 24 restrictions. Thus, the optimum structure parameters are obtained to satisfy the path points accurately.

  • PDF

Effect of the separating streamline curvature on the axisymmetric backward-facing step flow (박리 유선의 곡률 변화가 축대칭 후향계단 흐름에 미치는 영향)

  • Kim, K.C.;Boo, J.S.;Yang, J.P.;Jung, J.Y.
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.20 no.4
    • /
    • pp.1510-1520
    • /
    • 1996
  • An experimental study on the flow over the axisymmetric backward-facing step was carried out. The purpose of the present study is to investigate the effect of the separating streamline curvature on the reattachment length and to understand the structure of recirculating flows. Local mean and fluctuating velocity components were measured in the separating and reattaching axisymmetric region of turbulent boundary layer on the wall of convex cylinder placed in a water tunnel by using 2-color 4-beam fiber optics laser Doppler velocimetry. The study demonstrates that the reattachment length increases with increasing separating streamline curvature. It is also observed that the reverse flow velocity and turbulent kinetic energy increase with an increase in the separating streamline curvature. In addition, the behavior of maximum turbulent stresses show that the effect of separating streamline curvature is larger in the region of recirculating zone(X/H<2) than in the region of reattachment point.

Characteristic Analysis and Selection of Process Parameters in Direct Rolling Processes (직접압연공정의 특성해석 및 공정변수 선정)

  • 박영준;조형석;이원호;강태욱
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.04a
    • /
    • pp.384-388
    • /
    • 1997
  • Recently,direct rolling process has been drawing increasing interests because production cost be greatly reduced by eliminating subsequent hot rolling processes. Such a process has been characterized to prosuce thin steel strip (thickness 1~5mm) directly from molten metal and to skip over the conventional hot rolling processes. However, since there are several process parameters, which affect the quality of product,and their relationship between the parametersare very complex,it is therefore very difficult to realize the process design and the quality control. To overcome these difficulties quantitative relationship between the parameters are investigated through a numerical analysis. Form these results, it is found that solidification final point is the most important paramter which is critical to quality of the strip. Also,the multiple regression model is obtianed to determine their relationship from the solidification final point and roll separating force which can be easily estimated

  • PDF

Effect Of The Separating Shear Layer on the Flow Over an Axisymmetric Backward-Facing Step (박리전단층이 축대칭 하향단흐름에 미치는 영향)

  • 부정숙;김경천;양종필
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.19 no.4
    • /
    • pp.1102-1115
    • /
    • 1995
  • An experimental study on the flow over the axisymmetric backward-facing step was carried out. The purpose of the present study is to investigate the effect of the boundary layer thickness at the separation point on the reattachment length and to understand the structure of the recirculating flows. Local mean and fluctuating velocity components were measured in the separating and reattaching axisymmetric turbulent boundary layer over the wall of convex cylinder placed in a water tunnel by using 2-color 4-beam fiber optics laser Doppler velocimetry. The study demonstrated that the reattachment length increases with increasing boundary layer thickness. It was also observed that the reverse flow velocity and turbulent kinetic energy decrease with an increase in the momentum thickness at the separation point. The measured velocity field suggests that the boundary layer thickness at the separation can affect definitely on the formation of corner eddy.

CHARACTERIZATIONS OF (JORDAN) DERIVATIONS ON BANACH ALGEBRAS WITH LOCAL ACTIONS

  • Jiankui Li;Shan Li;Kaijia Luo
    • Communications of the Korean Mathematical Society
    • /
    • v.38 no.2
    • /
    • pp.469-485
    • /
    • 2023
  • Let 𝓐 be a unital Banach *-algebra and 𝓜 be a unital *-𝓐-bimodule. If W is a left separating point of 𝓜, we show that every *-derivable mapping at W is a Jordan derivation, and every *-left derivable mapping at W is a Jordan left derivation under the condition W𝓐 = 𝓐W. Moreover we give a complete description of linear mappings 𝛿 and 𝜏 from 𝓐 into 𝓜 satisfying 𝛿(A)B* + A𝜏(B)* = 0 for any A, B ∈ 𝓐 with AB* = 0 or 𝛿(A)◦B* + A◦𝜏(B)* = 0 for any A, B ∈ 𝓐 with A◦B* = 0, where A◦B = AB + BA is the Jordan product.

A Study on Ground and Object Separation Techniques Utilizing 3D Point Cloud Data in Urban Air Mobility (UAM) Environments (UAM 환경에서의 3D Point Cloud Data 지면/객체 분리 기법 연구)

  • Bon-soo Koo;In-ho choi;Jae-rim Yu
    • Journal of Advanced Navigation Technology
    • /
    • v.27 no.4
    • /
    • pp.481-487
    • /
    • 2023
  • Recently, interest in UAM (Urban Air Mobility) has surged as a critical solution to urban traffic congestion and air pollution issues. However, efficient UAM operation requires accurate 3D Point Cloud data processing, particularly in separating the ground and objects. This paper proposes and validates a method for effectively separating ground and objects in a UAM environment, taking into account its dynamic and complex characteristics. Our approach combines attitude information from MEMS sensors with ground plane estimation using RANSAC, allowing for ground/object separation that isless affected by GPS errors. Simulation results demonstrate that this method effectively operates in UAM settings, marking a significant step toward enhancing safety and efficiency in urban air mobility. Future research will focus on improving the accuracy of this algorithm, evaluating its performance in various UAM scenarios, and proceeding with actual drone tests.

Implementation of Speech Recognizer using DSP(Digital Signal Processor) (DSP를 이용한 음성인식기 구현)

  • 임창환;문철홍;전경남
    • Proceedings of the IEEK Conference
    • /
    • 2000.11d
    • /
    • pp.187-190
    • /
    • 2000
  • In this paper, implementation of speech Recognizer system, Separated from Personal computer. By using DSP, this intends to extend the voice recognizing, limited into PC because of amount of data and calculations. For this performance The thesis uses the real time End point detector and organizes no additional device between human and the system, characteristic vector are that detects End point and voice from absolute energy and ZCR, that uses 12 difference Cepstrum from LPC, that uses the method to compensate the process of pattern separating and pre-calculated standard pattern limitation.

  • PDF

A Study about the Separation of the materials Used in Refractory Cast Dies For Making All Ceramic Crowns (전부 주조관 제작을 위한 내화모형재 분리에 관한 연구)

  • Shin, Moo-Hak;Kim, Yeoun-Soo;Choi, Un-Jea
    • Journal of Technologic Dentistry
    • /
    • v.21 no.1
    • /
    • pp.123-130
    • /
    • 1999
  • I attempted to suggest a better method to separate a refractory cast in order to solve the problems caused by bonding between refractory casts and ceramics in the firing-processing of all ceramic crowns as a part of dental prosthodontics. I emphasize the advantages and effectiveness of easy separation after firing by using the separating materials about the refractory cast dies. 1. We must not usse HF(55%) that is used as the chemical separating methods. 2. We decrease such methods as grinding, blasting, bur, and point 3. We can save time, costs and manual labors by using this methods. 4. This method regulates the expansion and constriction of heat because of the chemical reaction of the separating materials. 5. This method contribute to the breaking down without modification by minimizing the chemical and mechanical damages of the marginal and interior parts.

  • PDF

A Real Time Quadrotor Autonomous Navigation and Remote Control Method (실시간 쿼드로터 자율주행과 원격제어 기법)

  • Son, Byung-Rak;Kang, Seok-Min;Lee, Hyun;Lee, Dong-Ha
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.8 no.4
    • /
    • pp.205-212
    • /
    • 2013
  • In recent, the demand of Unmanned Aerial Vehicles (UAVs) that can autonomous navigation and remote control has been increased in military, civil and commercial field. Particularly, existing researches focused on autonomous navigation method based on vanish point and remote control method based on event processing in indoor environments. However, the existing methods have some problems. For instance, a detected vanish point in intersection point has too much detection errors. In addition, the delay is increased in existing remote control system for processing images in real time. Thus, we propose improved vanish point algorithm by removing detection errors in intersection point. We also develop a remote control system with android platform by separating flying control and image process. Finally, we compare the proposed methods with existing methods to show the improvement of our approaches.