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The Information Sharing Platform for Port Container Terminal Logistics using Virtual Reality*
Fan Shu, Weijian Mi, Ziqi Xu Logistics Engineering School Shanghai Maritime University
Shanghai, China [email protected] , [email protected]
* This work is supported by SECRP Grant #T0601 to Z.Q. Xu.
Abstract - Port container terminals are essential intermodal interface in the global transportation network. Owing to advances of container logistics in today’s globalized economy, the competitive edge of container terminals has shifted to information management paradigm for the purpose of cost- and time-efficiency. However, an effective yet systematic information sharing strategy, in terms of information acquisition, processing, communication, storage, display and analysis, has not been well addressed. The traditional information from port operation management was conducted using numerical and diagrammatical formats. As a result, it is an imperative to employ the latest visual technologies, i.e. virtual reality (VR) and geographical information system (GIS), to resolve these impacts so as to enhance the efficiency of port logistics. Accordingly, a novel logistics information system, i.e. a VR-based information-sharing infrastructure, which paves a new venue for container terminal operation and control, is proposed and investigated. Finally, a case study on Tianjing Container Port in China is consequently presented to illustrate this approach. It is indicated that the proposed VR-based system can be effectively applied for container terminals operation and facilitate the container terminals logistics process. Index Terms – Port container terminal logistics, Information sharing platform, Virtual reality, system modeling and simulation.
I. INTRODUCTION
As a starting and terminal point of seaborne transportation, the port has become a hub comprising physical, information and financial flows. Moreover, with advances of logistics management, the port has transformed from a ‘transportation centre’ into a ‘logistics centre’. The port logistics is accordingly composed of two perspectives: namely, a micro viewpoint regarding such terminal operations as docking, transportation and inventory; and a macro viewpoint regarding social factors [1, 2]. In this regard, the information flow rather than physical flow secures a crucial position in port logistics. It pertains to a transparent process that can be analysed and controlled efficiently. Based on this notion, the port information platform using visual technologies is accordingly developed for port management purpose. Especially, container terminals are the most important points in port enterprise logistics, container operation management using information technologies should be further studied. The traditional operation management and control systems of container terminals involve the information
management throughout container handling process in terms of numerical and diagrammatical formats. Thus for diversity of container operation activities, it is extremely tough for container operators to handle the information in a real-time manner because of data redundancy and response delay [3]. Owing to the rapid development of information technology (IT), the virtual reality (VR) and geographical information system (GIS) technology paves a novel venue to operate and control container terminals effectively, so as to expedite container operation significantly.
II. OVERVIEW OF CONTAINER PORT LOGISTICS INFORMATION
The port information platform is established to integrate both information sources of enterprise and social logistics. It bridges diverse information management systems, including enterprise and user information. From an internal viewpoint, information communication and coordination is rather critical amongst diverse terminals in a specific port, as well as various departments within a specific terminal. On the other hand, from an external viewpoint, such enterprises as shipping companies or agents, commodity owners or agents, shipping contractors and custom inspectors. Moreover, shipping companies and custom inspections contact with diverse port-level administrative departments (e.g. scheduling, transportation and finance) directly; whereas transportation contractors and commodity owners contact with diverse terminal-level departments directly. As a result, a multiple-level management mode is imperative in consideration with both internal and external issues.
Fig.1 Illustration of correlation amongst port departments Fig.1 illustrates the correlation amongst internal and external departments within a port. The logistics information platform communicates frequently with the department-level
Port Administrative Dept
Terminal N
Custom Inspectors Shipping Agents
Commodity Owners Shipping
Contractors
�����
Terminal 1
Finance
Scheduling
Transport
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1-4244-1531-4/07/$25.00 © 2007 IEEE. 2570
Proceedings of the IEEEInternational Conference on Automation and Logistics
August 18 - 21, 2007, Jinan, China
computer management systems, in which information sources stem from multiple entities. With advances of information technologies (ITs), port information is acquired based on information systems instead of manual working. For instance, vessel charts and cargo manifests are currently transferred from shipping companies to terminal operation departments via electronic data exchange (EDI) technology. IC cards are used while container trucks enter operation zones. Further studied, the radio frequency identification (RFID) technology is employed in replacement of IC cards. The global position system (GPS) is also applied for in-site monitoring and dynamic scheduling. Remote monitoring system (RMS) is as well equipped through programmed logic controller (PLC) to transmit equipment information into Internet advances directly. These examples indicate that diverse acquisition technologies are possibly used under a uniformed system. After the introduction of logistics information, the information regarding object positions and motions are emphasized. Most information is described as a text-based format rather than a spatial object, yet it is a trend to link the spatial information with textual information. The spatial information, such as storage yards, berthing of vessels and transportation route of yard machines, can be used to establish decisions regarding production management, e.g. storage space allocation [4,5], berth allocation [6,7,8] and yard cranes or tucks dispatching [9,10]. Based on these understandings, port information platform is such a complicated system that its efficiency is now an impact. In this regard, logistics information management involves not only information storage, record and display but also information analysis and evaluation. As such, it is critical to establish a visualized data-mining strategy on the basis of an information-sharing infrastructure.
III. ESTABLISHMENT OF INFORMATION SHARING PLATFORM
At present, various management sub-systems, which involve different logistics information, are applied in terminals [11]. For example, the real-time production management system is used for terminal production control; the financial system is employed based on terminal operation data; the facility service system is aimed at equipment maintenance and repair; and remote monitoring system is deployed for equipment condition monitoring and remote servicing. Although these systems are used for different purposes, there exist close relationships amongst them. In details, the equipment idle information should be sent to real-time production system through remote monitoring system, so as to fast respond to the break-down equipment and dynamically re-allocate the machinery. Meanwhile, the idle information should be sent to equipment service system so as to undergo maintenance and repair planning. The import and export time and operation records from production system should be sent to financial system for calculating inventory, contracting and operation fees so as to settle accounts between consignor and terminals. Similarly, the equipment maintenance time, cost, consumables procurement and consumption should be sent to financial system so as to
conduct the internal cost estimation. Accordingly, there exists a public information area. However, the communication amongst different systems is still problematic due to intensive inputs for the same information, data redundancy and error inputs. To resolve this impact, following techniques are adopted: 1) Appropriate procedure of information system development: The sequence of information system development should be concordant with the direction of information flow amongst different management sub-systems. 2) Close cooperation between information system developers and enterprise system engineers: The system maintenance and updating should be conducted based on a team-work of both system developers and enterprise staffs, specifically for development stream and database design. 3) Effective establishment of unified and standard event code tables: Code tables regarding commodity, machinery and port can be directly used; or mapping tables are newly set up so as to guarantee code consistency. Nevertheless, there unavoidably exists inconsistency among historical data in a developed port. As such, establishment of a sharing infrastructure secures a crucial position in port development strategy for information system. The infrastructure includes a two-level mechanism, namely, an administrative level and an operative level. The administrative level departments include port service authority that manages subordinate terminals. As such, a so-called scheduling center is usually set up for integrated information management, for example, such activities as customs declaration, container-collection appointment and acceptance service are handled through an integrated information platform. However, different operation systems and databases may possibly be used by different terminals, so that data transmission is rather time- and cost-consuming. Based on this understanding, the information-sharing platform is established according to the information singularity strategy, that is, the unified information is distributed to subordinate terminals by port authority. Following issues should be considered: 1) For port networking, the terminal departments are able to connect with the enterprise server. 2) For system development, the generality and typicality among terminals should be equivalently emphasized.
IV. THEORETICAL BASIS OF VISUAL TECHNOLOGY
A. Real-time-driven Database In general, the VR-based container operation management systems (COMS) are developed based on legacy systems. These systems employ existing databases and drive motional objects for 3D scenes in a real-time fashion, which represent actual conditions of container operation. Accordingly, the relationship between traditional and VR-based COMS is shown in Fig.2.
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Fig.2 Traditional versus VR-based COMS
B. Virtual-reality technology The VR technology provides an interacting environment for modeling and simulating operation activities by means of the three-dimensional (3D) visualization [12]. As a result, this enables container terminals in controlling operation process and thereafter making decisions efficiently. The VR technology is used to create a virtual world in terms of a computer system, which provides a mechanism for virtual environment and navigation scene. Meanwhile, it can represent the motion of scenery objects using simulation techniques; whereas the 3D world can be requested and responded through the human-computer interfaces (HCI) [13]. In details, the existing COMS is adapted to a virtual environment so that container terminal operators can attain and then respond towards the real-time information conveniently and intuitionally. Specifically in this study, the VR-based COMS, which runs under a VC.NETTM environment, is implemented using a modeling software named CreatorTM and a simulation-driven software called VegaTM.
C. Geographical information system technology Traditionally, information is represented in a textual form to describe an object from diverse viewpoints, so as to map into a multiple-field table in terms of multi-attributes [14]. With the development of logistics, spatial information is further stressed as geographical information, which can be categorized as follows: 1) Attribute information: i.e. traditionally-described information that covers various attributes of an object, involving manifest, attributes of containers, operation records of gantry cranes. 2) Geographical information: i.e. space-related information that is related much to 3-dimensional (3D) spatial information, such as terminal yard location and container vessel types. The 3D spatial information can be transferred into 2D spatial information if the z-coordination is set to 0, such as terminal yard layout map.
V. IMPLEMENTATION OF VR-BASED COMS
The modeling for VR-based COMS is conducted based on the 2D models. Simultaneously, a number of transformation interfaces are provided for various formatted files to avoid redundancy of modeling tasks [15]. Due that a large number of scene models and objects exist during the simulation process, an SGI workstation, together with CreatorTM software, is applied to generate the scene models of container terminals. This is realized based on the surveying information that contains dimensions and locations of objects. For this purpose, these models are further simplified. A. Static Scene Modeling The static scene includes such motionless objects as ground and sea levels, buildings and plants. As this work focuses on the container yards, other objects are included in the static scene. In this respect, they are grouped into a unified modeling file. Therefore, following tasks are carried out within the modeling process. 1) File format transformation: Prior to inputting to CreatorTM, the existing models are transformed into the demanded formats. These models are then optimized to omit some details that may complicate the modeling process. 2) External database introduction: In order to facilitate the storage space saving and virtual data updating, the external databases, which store existing models, are utilized in this study. In so doing, the existing modeling data are introduced and re-allocated into appointed databases. 3) Texture acquisition and creation: On the basis of photos, the texture acquisition is conducted using PhotoShopTM. The colors are fused via a combination of several photos so as to create new textures. Alternatively, textures of a specific photo are preceded in terms of chromatics degree, saturation degree and luminosity. Besides universal textures, some transparent textures, e.g. trees and backgrounds in the form of *.rgba or *.inta format, are further handled by PhotoShopTM via a CreatorTM plugin.
B. Motional Scene Modeling The motional scene, including such moving objects as container, tractor-trailers and cranes, is driven and coordinated by the information that is stored in databases. In details, 1) Three types of textures are respectively created for different containers, e.g. 20 and 40 inches. 2) The gantry cranes, which possess both global and local motions, are rather complicated amongst modeling objects. These motions are so inter-dependent that are modeled according to the changes of object locations and sizes. This is fulfilled by adopting CreatorTM hierarchical data structure, i.e. OpenFlight. Degree of freedom (DOF) nodes are added into the modeling database hierarchy in order that special parts of gantry crane can move around, respectively. A DOF establishes a local coordinate system, and the geometry it controls moves towards the axes of the coordinate system. 3) The models of container tractor-trailers are significantly simplified in the form of presenting the appearance rather than structure of the tractor-trailers.
C. Modeling Files Integration
Shared
DB
VR-base
Container Operation System
Traditional Container Operation System
Query & Statistical
CFS
Container management
Operation Mgt & Control
CTS
Gateway Entrance / Exit
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Consequently, two categories of modeling files are formed. One is an integrated file of static objects (including static objects and backgrounds) accompanied by some pre-defined models from external databases. The others are relevant files of motional objects (including container, tractor-trailers, crane objects). The workflow of these modeling files is illustrated in Fig.3. In details, LynxTM graphical user interfaces (GUI) are added to the interfaces of static objects; while applications via VegaTM are associated with the operations of motional object numbers and dimensions based on VC.NETTM programming [16].
VI. A CASE STUDY
A case study on Tianjing Container Port in China is consequently presented to illustrate this approach. In this regard, such 3D simulation software as CreatorTM and VegaTM
are used for system implementation, together with VC.NETTM for in-depth VegaTM programming. A GUI of the VR-based COMS is presented in Fig.4. Some detailed interpretations are presented as follows.
A. Pre-definition of Application Programs Define abbreviations and acronyms the first time they are used in the text, even if they have been defined in the abstract. Abbreviations such as IEEE, SI, MKS, CGS, ac, dc, and rms do not have to be defined. Do not use abbreviations in the title unless they are unavoidable.
B. Secondary Development of Application Programs Upon completion of pre-defined files, the parameters of application programs are initialized. The motional objects are simulated using such object-oriented (O-O) programming tool-kits as VC.NETTM via VegaAPI functions. Due that VC.NETTM is used as the development platform for MFC-based application programs, the VR-based COMS possesses good interfacing and visualization functionalities through VegaTM. In details, 1) Access and track database: Once some changes of database records are detected, the 3D models, which denote different operation activities, are responded to these changes (Fig.5).
Fig.3 Workflow of static and motional modeling files
Fig.4 An illustration of VR-based terminal scheduling
2) Drive scene models: The changes of database information are represented by the changes of displacement and color on account of VegaTM objects. In this case, the models are rendered based on the interaction amongst databases, tables and objects (Fig.6). 3) Render modeling scenes: After the color table is set up, it is easy to find the monitored containers or container categories from color changes of objects. For the purpose of events tracking, users can click 3D objects using mouse or key in relevant query information.
VII. CONCLUSIONS
To ride on the demands of port operation reliability, a port logistics information platform is accordingly proposed. By incorporating with port management sub-systems, an information-sharing platform is established; whereas a visualized data mining strategy is postulated. Through information communication amongst port entities, an integrated approach is attempted to combine both data mining and visualization technologies. Therefore, it is envisaged that port logistics information could be effectively utilized within a reliable logistics information platform.
Fig.5 Relationship amongst RecordSets, linked lists and scene objects
Linked list Structure (Linked list Classes)
Initialization
Initialization
Controlling
Comparisons
Updating
Scene Objects
Database Information (RecordSets Classes)
Modeling files
via Creator TM
Static Scene
(including static objects
and backgrounds)
Motional Scene
(including container,
truck, crane objects)
LynxTM graphical user
interfaces ( GUI added
to object interfaces)
Application
Based on Vega TM
(Operations of object
numbers and dimensions
via VC.NET TM)
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Fig.6 Illustration of scene objects controlled by databases and tables The conventional operation management systems (COMS) of container terminals are related to the information organization within container handling process in terms of numerical and diagrammatical formats. Hence for various container operation activities, it is rather difficult for container operators to handle the information in a real-time manner due to data redundancy and response delay. Because of the advent of information technology (IT), the virtual reality (VR) technology provides a new way to operate container terminals effectively. In this regard, the VR technology creates an integrated environment to model and simulate operation activities using the three-dimensional (3D) visualization. Generally speaking, the VR-based COMS is developed based on existing systems. These systems should drive motional objects for 3D scenes in a real-time manner. The VR technology is applied to generate a virtual world as a computer system. Alternatively, it can represent the motion of scenery objects by employing simulation techniques; meanwhile, the 3D platform can be operated via the human-computer interfaces (HCI). The VR-based COMS models are conducted on the basis of the 2D models. Because of a lot of scene models and objects during the simulation process, an SGI workstation together with CreatorTM software is utilized to generate the scene models of container terminals. Upon completion of object modeling, two types of modeling files are formed. To a detailed extent,
LynxTM graphical user interfaces (GUI) are generated to interface static objects; whereas applications via VegaTM are conducted to operate motional object numbers and dimensions based on VC.NETTM programming. In this regard, such 3D simulation software as CreatorTM and VegaTM are used for system implementation, together with VC.NETTM for in-depth VegaTM programming. A two-step approach is adopted, comprising pre-definition and secondary development of application programs. In summary, the VR technology is applied for system modeling and simulation. This provides a cooperative platform for geometrical and motional modelling, where operation activities are visualized in three-dimensional (3D) formats. Furthermore, data of motional models are driven by a real-time database, which contains operation management information. A case of Tianjing Container Port in China is consequently employed to study this approach. It is envisaged that the proposed VR-based system is proven effective in container terminal operation.
ACKNOWLEDGMENT
The authors would like to thank an anonymous referee for his/her careful review and helpful suggestion. This research work is sponsored by Shanghai Education Committee Research Projects (SECRP).
Incoming Container tractor-trailer Locations
RecordSets Classes (Current
Information)
Linked list Classes (Existing
Information)
Comparisons
Y
RecordSets Increasing
Add Vega-modeled Container & tractor-trailer Objects (Both within the scene)
Unloading
Import Voyage
N Y
Add Vega-modeled tractor-trailer Objects to Search for Container Objects
(Tractor-trailer within the scene only)
Outgoing Loading
RecordSets Reducing
N
Import Voyage
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