• Title/Summary/Keyword: Docking

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A Study on Selection of Cross-Docking Center based on Existing Logistics Network (기존 물류 네트워크 기반에서 크로스 - 도킹 거점선정에 관한 연구)

  • Lee, In-Chul;Lee, Myeong-Ho;Kim, Nae-Heon
    • IE interfaces
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    • v.19 no.1
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    • pp.26-33
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    • 2006
  • Many Firms consider the application of a cross-docking system to reduce inventory and lead-time. However, most studies mainly concentrate on the design of a cross-docking system. This study presents the method that selects the cross-docking center under the existing logistics network. Describing the operation environment to apply the cross-docking system, the selection criteria of the cross-docking center, and the main constraints of transportation planning under the environment of multi-level logistics network, we define the selection problem of the cross-docking center applied to a logistics field. We also define the simulation model that can analyze variously the cross-docking volume and develop the selection methodology of the cross-docking center. The simulation model presents the algorithm and influence factors of the cross-docking system, the decision criteria of the system, policy parameter, and input data. In addition, this study analyzes the effect of increasing the number of simultaneous receiving and shipping docks, and the efficiency of the overnight transportation and cross-docking by evaluating each scenario after simulating the scenarios with the practical data of the logistics field.

Study on the Docking Algorithm for Underwater-Docking of an AUV Using Visual Guidance Device (광학식 유도장치를 이용한 자율 무인잠수정의 수중 도킹 알고리즘에 관한 연구)

  • Choi, Dong-Hyun;Jun, Bong-Huan;Lee, Pan-Mook;Kim, Sang-Hyun;Lim, Geun-Nam
    • Journal of Ocean Engineering and Technology
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    • v.21 no.3 s.76
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    • pp.33-39
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    • 2007
  • The more deeply the researches make progress in ocean researches including the seabed resource investigation or the oceanic ecosystem investigation, the more important the role of UUV gets. In case of study on the deep sea, there are difficulties in telecommunications between AUV and ships, and in data communication and recharging. Therefore, docking is required. In AUV docking system, the AUV should identify the position of docking device and make contact with a certain point of docking device. MOERI (Maritime & Ocean Engineering Research Institute), KORDI has conducted the docking testing on AUV ISIMI in KORDI ocean engineering water tank. As AUV ISIMI approachs the docking device, there is some cases of showing an unstable attitude, because the lights which is on Image Frame are disappeared. So we propose the docking algorithm that is fixing the rudder and stem, if the lights on image frame are reaching the specific area in the Image Frame. Also we propose the new docking device, which has a variety of position and light number. In this paper, we intend to solve the some cases of showing an unstable attitude that were found in the testing, which, first, will be identified the validity via simulation.

Docking Assessment Algorithm for AUVs with Uncertainties (불확실성이 포함된 무인잠수정의 도킹 평가 알고리즘)

  • Chon, Seung-jae;Sur, Joo-no;Jeong, Seong-hoon
    • Journal of Advanced Navigation Technology
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    • v.23 no.5
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    • pp.352-360
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    • 2019
  • This paper proposes a docking assessment algorithm for an autonomous underwater vehicles (AUVs) with sensor uncertainties. The proposed algorithm consists of two assessments, state assessment and probability assessment. The state assessment verifies the reachability by comparing forward distance to the docking station with expected distance to reach same depth as the docking station and necessity for correcting its route by comparing calculated inaccessible areas based on turning radius of the AUV to position of the docking station. When the AUV and the docking station is close enough and the state assessment is satisfied, the probability assessment is conducted by computing success probability of docking based on the direction angle, relative position to the docking station, and sensor uncertainties of the AUV. The final output of the algorithm is decided by comparing the success probability to threshold whether to try docking or to correct its route. To verify the validation of the suggested algorithm, the scenario that the AUV approaches to the docking station is implemented through Matlab simulation.

Prediction of Chiral Discrimination by β-Cyclodextrins Using Grid-based Monte Carlo Docking Simulations

  • Choi, Young-Jin;Kim, Dong-Wook;Park, Hyung-Woo;Hwang, Sun-Tae;Jeong, Karp-Joo;Jung, Seun-Ho
    • Bulletin of the Korean Chemical Society
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    • v.26 no.5
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    • pp.769-775
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    • 2005
  • An efficiency of Monte Carlo (MC) docking simulations was examined for the prediction of chiral discrimination by cyclodextrins. Docking simulations were performed with various computational parameters for the chiral discrimination of a series of 17 enantiomers by $\beta$-cyclodextrin ($\beta$-CD) or by 6-amino-6-deoxy-$\beta$-cyclodextrin (am-$\beta$-CD). A total of 30 sets of enantiomeric complexes were tested to find the optimal simulation parameters for accurate predictions. Rigid-body MC docking simulations gave more accurate predictions than flexible docking simulations. The accuracy was also affected by both the simulation temperature and the kind of force field. The prediction rate of chiral preference was improved by as much as 76.7% when rigid-body MC docking simulations were performed at low-temperatures (100 K) with a sugar22 parameter set in the CHARMM force field. Our approach for MC docking simulations suggested that the conformational rigidity of both the host and guest molecule, due to either the low-temperature or rigid-body docking condition, contributed greatly to the prediction of chiral discrimination.

Parametric Study for Assessment of Reaction Forces on Ship Docking Supports

  • Ryu, Cheol-Ho;Kim, Sung-Chan;Lee, Jang-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.3
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    • pp.290-301
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    • 2013
  • The docking analysis of a global ship structure is requested to evaluate its structural safety against the reaction forces at supports during docking works inside a dry dock. That problem becomes more important recently as the size of ships is getting larger and larger. The docking supports are appropriately arranged in a dock to avoid their excessive reaction forces which primarily cause the structural damages in docking a ship and, up to now, the structural safety has been assessed against the support arrangement by the finite element analysis (FEA) of a global ship structure. However, it is complicated to establish the finite element model of the ship in the current structural design environment of a shipyard and it takes over a month to finish the work. This paper investigates a simple and fast approach to carry out a ship docking analysis by a simplified grillage model and to assign the docking supports position on the model. The grillage analysis was considered from the motivation that only the reaction forces at supports are sufficient to assess their arrangement. Since the simplified grillage model of the ship cannot guarantee its accuracy quantitatively, modeling strategies are proposed to improve the accuracy. In this paper, comparisons between the proposed approach and three-dimensional FEA for typical types of ships show that the results from the present grillage model have reasonably good agreement with the FEA model. Finally, an integrated program developed for docking supports planning and its evaluation by the proposed approach is briefly described.

Effect of Consecutive Ship Docking and Undocking on Seawater Circulation in Harbor (선박의 연속적 접⋅이안이 항내 해수순환에 미치는 영향)

  • Hong, Namseeg
    • Journal of Ocean Engineering and Technology
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    • v.30 no.3
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    • pp.177-185
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    • 2016
  • In this study, the model developed by Hong (2012) was modified to describe the consecutive docking/undocking situation and was also applied to investigate the effect on seawater circulation in Busan port by consecutive docking/undocking at the connecting bridge of Busan port. Numerical experiments for various docking/undocking cases were performed by dumping the initial concentration within Busan Port and indicated that the concentration in Busan port becomes steady state without numerical wiggles after sufficient time (at least 20 or 30 days). In addition, it was found that the seawater circulation under ship docking was slightly reduced in comparison with that under ship undocking, and the approach time to the target concentration under all the docking cases increased in comparison with the undocking case.

A Design of Molecular Docking Application in Grids (그리드에서 Molecular Docking 어플리케이션 설계)

  • 진성호;이화민;이대원;이종혁;박성빈;유헌창
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.466-468
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    • 2004
  • Molecular modelling은 시뮬레이션을 통해 온도, 압력 등과 같은 분자 운동에 영향을 미칠 수 있는 요소를 설정한 후 분자의 움직임을 관찰하는 방법으로 신약, 신소재, 고분자 개발에 있어서 연구 개발 기간을 단축하는 효과적인 방법이다. 기존의 molecular modelling 어플리케이션들은 슈퍼컴퓨터나 단일 클러스터를 이용하여 작업을 수행하도록 설계되어 비용과 성능 측면에서 문제점을 가지고 있다. 1590년대 중반 지리적으로 분산되어 있는 광범위한 자원들을 공유하여 장기간 소요되는 컴퓨팅 작업의 성능 향상 및 비용절감을 목적으로 하는 그리드(grid)가 등장하였다. 이에 본 연구에서는 효율적이면서도 저비용을 갖는 molecular modelling 어플리케이션 개발을 위해 그리드를 기반으로 최적 자원 선택 브로커를 이용하는 molecular docking 어플리케이션을 제안한다. 이를 위해 우리는 molecular docking을 수행하는 그리드 환경의 계층 구조를 설계하고 효율적 작업 수행을 위한 최적 자원 선택 브로커를 설계하였다. 그리고 그리드 환경에서 molecular docking 어플리케이션의 효과적인 수행을 위해 molecular docking 연산 모델을 정의하고 필요한 molecular docking 어플리케이션의 요소들을 설계하였다.

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Flexible Docking Mechanism with Error-Compensation Capability for Auto Recharging System (자동충전 시스템을 위한 오차보정이 가능한 유연한 도킹 메커니즘)

  • Roh, Se-Gon;Park, Jae-Hoon;Song, Young-Kook;Yang, Kwang-Woong;Choi, Moo-Sung;Kim, Hong-Seok;Lee, Ho-Gil;Choi, Hyouk-Ryeol
    • The Journal of Korea Robotics Society
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    • v.2 no.4
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    • pp.289-296
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    • 2007
  • The docking and recharging system for a mobile robot must guarantee the ability of the mobile robot to perform its tasks continuously without human intervention. In this paper, two docking mechanisms are proposed with localization error-compensation capability for the auto recharging system. Friction forces or magnetic forces are used between the docking parts of the docking module and those of the docking station. In addition, an auto recharging system is developed to control the power. Since the system is modularized, it can easily be adapted to other robots.

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A Development of Docking Phase Analysis Tool for Nanosatellite

  • Jeong, Miri;Cho, Dong-Hyun;Kim, Hae-Dong
    • Journal of Astronomy and Space Sciences
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    • v.37 no.3
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    • pp.187-197
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    • 2020
  • In order to avoid the high cost and high risk of demonstration mission of rendezvous-docking technology, missions using nanosatellites have recently been increasing. However, there are few successful mission cases due to many limitations of nanosatellites like small size, power limitation, and limited performances of sensor, thruster, and controller. To improve the probability of rendezvous-docking mission success using nanosatellite, a rendezvous-docking phase analysis tool for nanosatellites is developed. The tool serves to analyze the relative position and attitude control of the chaser satellite at the docking phase. In this tool, the Model Predictive Controller (MPC) is implemented as a controller, and Extended Kalman Filter (EKF) is adopted as a filter for noise filtering. To verify the performance and effectiveness of the developed tool for nanosatellites, simulation study was conducted. Consequently, we confirmed that this tool can be used for the analysis of relative position and attitude control for nanosatellites in the rendezvous-docking phase.

Using reverse docking to identify potential targets for ginsenosides

  • Park, Kichul;Cho, Art E.
    • Journal of Ginseng Research
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    • v.41 no.4
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    • pp.534-539
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    • 2017
  • Background: Ginsenosides are the main ingredients of ginseng, which, in traditional Eastern medicine, has been claimed to have therapeutic values for many diseases. In order to verify the effects of ginseng that have been empirically observed, we utilized the reverse docking method to screen for target proteins that are linked to specific diseases. Methods: We constructed a target protein database including 1,078 proteins associated with various kinds of diseases, based on the Potential Drug Target Database, with an added list of kinase proteins. We screened 26 kinds of ginsenosides of this target protein database using docking. Results: We found four potential target proteins for ginsenosides, based on docking scores. Implications of these "hit" targets are discussed. From this screening, we also found four targets linked to possible side effects and toxicities, based on docking scores. Conclusion: Our method and results can be helpful for finding new targets and developing new drugs from natural products.