Design and Simulation Study of a Monorail Network for the Inter-terminal Transport

Truong Ngoc Cuong,Seung-Pil Lee,Hwan-Seong Kim 한국항해항만학회 2020 한국항해항만학회 학술대회논문집 Vol.2020 No.춘계

In line with the trend of global transport volume which has increased rapidly over the years, internal transportation in seaports is always done with high frequency. Therefore, there is always a lot of potential for traffic jams as well as huge transportation costs and emissions. Many efforts to streamline inter-terminal container transport (ITT) through the development of automated vehicles and equipment as well as using private transport facilities to overcome these limitations. This paper aims to develop a framework to design, analyze and validate the efficiency of a new ITT system in a port area base on monorail network and automatic vehicle. By setting goals for performance indicators, the results showed that the system was highly efficient with 100% of the containers being delivered to their destination on time. Besides, a series of other performance tracking is provided to give an insight into the system s capabilities.

Design and Simulation of a Monorail Network for the Inter-terminal Transport

Ngoc Cuong Truong,김환성,김인용,DuyAnh Nguyen,Long Le Ngoc Bao 한국항해항만학회 2020 한국항해항만학회지 Vol.44 No.5

In line with the trend of global transport volume which has increased rapidly over the years, internal transportation in seaports is always conducted with high frequency. Thus, there is always much potential for traffic jams as well as high transportation costs and emissions. Many efforts have been initiated to streamline the inter-terminal container transport (ITT) through the development of automated vehicles and equipment as well as using private transport facilities to overcome these limitations. The purpose of this paper to develop a framework to design, analyze, and validate the efficiency of a new ITT system in a port area based on the monorail network and automatic vehicles. First, the number of shuttles and loaders was determined depending on the transport demand scenario. Next, a simulation model was applied to evaluate the system performance as well as gain more insight into the working process of the ITT system. Finally, by setting goals for the performance indicators, the results showed that the system was highly efficient with 100% of the containers delivered to their destination on time. Besides, a series of other performance tracking was provided to provide insight into the system's capabilities.

Suppression of Coupled Pitch-Roll Motions using Quasi-Sliding Mode Control

이상도,Truong Ngoc Cuong,Xiao Xu,유삼상 해양환경안전학회 2021 해양환경안전학회지 Vol.27 No.2

This paper addressed the problems of controlling the coupled pitch-roll motions in a marine vessel exposed to the regular waves in the longitudinal and transversal directions. Stabilization of the pitch and roll motions can be regarded as the essential task to ensure the safety of a ship’s navigation. One of the important features in the pitch-roll motions is the resonance phenomena, which result in unexpected large responses in terms of pitch and roll modes in some specific conditions. Besides, owing to its inherent characteristics of coupled combination and nonlinearity of restoring terms, the vessel shows various dynamical behaviors according to the system parameters, especially in the pitch responses. Above all, it can be seen that suppression of pitch rate remains the most significant challenge to overcome for ship maneuvering safety studies. To secure the stable upright condition, a quasi-sliding mode control scheme is employed to reduce the undesirable pitch and roll responses as well as chattering elimination. The Lyapunov theory is adopted to guarantee the closed stability of the pitch-roll system. Numerical simulations demonstrate the effectiveness of the control scheme. Finally, the control goals of state convergences and chattering reduction are effectively realized through the proposed control synthesis.

Intelligent Decision Support Algorithm for Uncertain Inventory Management

Le Ngoc Bao Long,Sam-Sang You,Truong Ngoc Cuong,Hwan-Seong Kim 한국항해항만학회 2023 한국항해항만학회 학술대회논문집 Vol.2023 No.1

This paper discovers a robust managerial strategy for a stochastic inventory of perishable products, where the model experiences changing factors including inner parameters and an external disturbance with unknown form. An analytical solution for the optimization problem can be obtained by applying the Hamilton-Bellman-Jacobi equation, however the policy result cannot completely suppress the oscillation from the external disturbance. Therefore, an intelligent approach named Radial Basis Function Neural Networks is applied to estimate the unknown disturbance and provide a robust controller to manipulate the inventory level more effective. The final results show the outstanding performance of RBFNN controller, where both the estimation error and control error are guaranteed in the predefined limit.

[ICACE2022] Prediction of container throughout of Qingdao port using optimized echo state network and improved particle swarm optimization

Zitong Qu,Cuong Truong Ngoc,Bao Long Le Ngoc,이승필,김환성 한국마린엔지니어링학회 2023 한국마린엔지니어링학회지 Vol.47 No.1

The container throughput in a container logistics system is an important technical index, irrespective of the method used to manage and forecast the port throughput. The Qingdao port, one of the most important ports in North China, has the advantage of being located in the "One belt One Road" position. At present, the forecasting method for the container transportation throughput of Qingdao port still needs to be optimized, and a model that can predict its development trend needs to be constructed. Echo state networks (ESN) have been widely used in time-series prediction owing to their simple structure and fast convergence speed. To solve the problem of the applicability of the random weight matrix generated in the ESN to a specific time series, this study proposes an improved particle swarm optimization (PSO) algorithm to optimize partial random weights in the ESN. Compared to the standard particle swarm optimization algorithm, the inertia weight and learning factor were adjusted to improve the optimization performance of the algorithm. Furthermore, by comparing the historical data with the predicted values, the prediction accuracy of the model was found to be over 98%. The container throughput of Qingdao port from 2022 to 2024 was predicted, which showed that the container throughput of Qingdao Port will maintain a rapid and stable growth trend.

Decision making for Shipping Network based on Adaptive Cumulative Prospect Theory

Pham Thi Yen,Nguyen Phung Hung,Truong Ngoc Cuong,Hwan-Seong Kim 한국항해항만학회 2023 한국항해항만학회 학술대회논문집 Vol.2023 No.1

This paper aims to propose optimal method to assess and cumulate the daily profit for liner shipping to support the shipping lines in making optimal decision with the highest average daily profit. This paper not only explains the actual calculated results align with decision-makers’ behavior from concepts indicated in cumulative prospect theory but also contributes to an easy-to-apply method for liner shipping network predictability in and provides optimal decision-making is helpful for shipping managers for the best effective selection of the most appropriate alternative under uncertainties.

Active Stabilization for Surge Motion of Moored Vessel in Irregular Head Waves

이상도,트롱 엥곡 쿠옹,서효,유삼상,Lee, Sang-Do,Truong, Ngoc Cuong,Xu, Xiao,You, Sam-Sang The Korean Society of Marine Environment and safet 2020 海洋環境安全學會誌 Vol.26 No.5

본 논문에서는 불규칙 선수파랑 조건에서 선박계류시스템의 전후동요를 억제하는 연구를 수행하였다. 두점식 계류시스템은 비선형복원력의 특성으로 인하여 규칙파 조건에서도 강한 비선형 응답 특성을 보인다. 종방향 불규칙 장파가 외란으로 선박계류시스템에 작용하게 되면 규칙파 외력이 입사하는 경우보다 변위와 속도에서 더욱 복잡한 비선형 거동이 발생한다. 계의 종동요 변위와 속도를 동시에 억제하기 위하여 슬라이딩모드 제어법(SMC)을 적용하였다. SMC는 매개변수의 불확실성 및 외란에 대한 강인성을 갖는 폐루프 시스템을 제공하지만, 채터링은 이 제어법을 사용할 때 큰 단점이 된다. 본 연구에서는 준 슬라이딩모드의 시그모이드 함수를 이용하여 불규칙 해양파의 외란 조건에서 채터링을 줄이고. 수렴의 정확성에 도달하는 목표를 달성하였다. 제어법의 유효성은 수치시뮬레이션을 통해 증명하였다. This study was focused on the stabilization of surge motions of a moored vessel under irregular head seas. A two-point moored vessel shows strong non-linearity even in regular sea, owing to its inherent non-linear restoring force. A long-crested irregular wave is subjected to the vessel system, resulting in more complex nonlinear behavior of the displacement and velocities than in the case of regular waves. Sliding mode control (SMC) is implemented in the moored vessel to control both surge displacement and surge velocity. The SMC can provide a closed-loop system with performance and robustness against parameter uncertainties and disturbances; however, chattering is the main drawback for implementing SMC. The goal of minimizing the chattering and state convergence with accuracy is achieved using a quasi-sliding mode that approximates the discontinuous function via a continuous sigmoid function. Numerical simulations were conducted to validate the effectiveness of the proposed control algorithm.