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The intelligent infrastructures research program aims at developing theory and applications concerning novel intelligent modes for control and management of the utilization of infrastructures, such as road, rail, energy, water and... more
The intelligent infrastructures research program aims at developing theory and applications concerning novel intelligent modes for control and management of the utilization of infrastructures, such as road, rail, energy, water and telecom. As an illustrative example of research topics within the scope of this program, distributed anticipatory control for automated guided vehicles is discussed. Today transport systems using automated guided
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ABSTRACT This paper provides a methodology, supported with a simulation tool, to determine the required stockyard size for dry bulk terminals. To determine the parameters that affect the required storage size, the storage factor was... more
ABSTRACT This paper provides a methodology, supported with a simulation tool, to determine the required stockyard size for dry bulk terminals. To determine the parameters that affect the required storage size, the storage factor was derived analytically. This factor defines the ratio between the annual throughput of a dry bulk terminal and the required stockyard size. Simulation is required for stockyard dimensioning when including the stochastic variations in the ship interarrival times, ship sizes and bulk material storage times. In addition, operational procedures were investigated that potentially increase the storage capacity. In a case study, the proposed approach was demonstrated by sizing the required stockyard area for a specific import terminal.
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ABSTRACT In this paper simulation is applied to reschedule the stacker-reclaimers operation to increase the dry bulk terminal's performance by reducing the waiting time of cargo trains being loaded at the terminal.... more
ABSTRACT In this paper simulation is applied to reschedule the stacker-reclaimers operation to increase the dry bulk terminal's performance by reducing the waiting time of cargo trains being loaded at the terminal. Stacker-reclaimers perform both the stacking and reclaiming of dry bulk materials. Due to the differences in loads between ships and cargo trains, the time needed for stacking and reclaiming varies considerably per job. The simulation tool developed can be used to support decisions when to interrupt ship servicing in favor of train loading based on the availability of transportation routes and expected disturbances. An experimental study demonstrated that ships and trains have to spend less time in the port when the stockyard lanes are accessible by two stacker-reclaimers due to the higher machines redundancy. Using the stacker-reclaimers rescheduling function the average port time of trains decreased without significantly affecting the port time of ships.
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This paper describes the complete modelling process for simulation, starting with the identification of agents and ending with a clear and unambiguous description of their behaviour that can be easily translated into each process-oriented... more
This paper describes the complete modelling process for simulation, starting with the identification of agents and ending with a clear and unambiguous description of their behaviour that can be easily translated into each process-oriented simulation platform. It focuses on the definition of agents, a subject which is described rarely. Agents usually "are there", emerging from the things one can see. Defining agents however, determines completely the range and content of a simulation and is not a trivial case. After a deliberate definition of the agents, a natural way to describe their behaviour is presented. These behaviour descriptions match the real process interaction approach. The described method is developed for educational reasons in order to teach discrete event simulation in a non-mathematical way, but is rather complete, coherent and well-defined.
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Theuseoftechnological tools inlogistics hasthe intention ofincreasing visibility, capacity andcontrol inthe supply chain. Decrease ofuncertainties duetoasymmetric data hasbeentheconstant challenge ofmanagement. Misdiagnosis ofsituations... more
Theuseoftechnological tools inlogistics hasthe intention ofincreasing visibility, capacity andcontrol inthe supply chain. Decrease ofuncertainties duetoasymmetric data hasbeentheconstant challenge ofmanagement. Misdiagnosis ofsituations andequipment, inaccurate production planning, shrinkage andcounterfeiting aresomeofthecommonproblems asaconsequence oferroneous information. Theideaofprognostic logistics istouserealtimeinformation andanintelligent system todiagnose andpredict early failures andhazardous situations. Theautomatic capture ofinformation inprognostic logistics hastheintent toreduce humanerrors. Automatic identification technologies enable thecreation ofaprognostic logistic network wherereal timeinformation isusedtomakeaccurate forecasting, pushing aproactive supply chaininstead ofareactive one. IndexTerms-Prognostics, logistics, automatic identification, RFID.
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Particle swarm optimization (PSO) attracts much attention due to its ability in solving complex practical engineering problems effectively. To further improve its performance, a heterogeneous particle swarm optimizer (HPSO) is proposed in... more
Particle swarm optimization (PSO) attracts much attention due to its ability in solving complex practical engineering problems effectively. To further improve its performance, a heterogeneous particle swarm optimizer (HPSO) is proposed in this work. Five widely used benchmark functions are selected to test its efficiency. Furthermore, five state-of-the-art improved PSO variants are selected for a comparisons purpose. The results demonstrate that HPSO is better than the other five algorithms. A logistics problem in aircraft manufacturing is then studied and solved. The results show HPSO's superiority over its tested PSO variants.
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Purpose– The macroscopic properties of dried sand can be correctly modelled when the accurate determination of the microscopic properties is available. The microscopic properties between the particles such as the coefficients of rolling... more
Purpose– The macroscopic properties of dried sand can be correctly modelled when the accurate determination of the microscopic properties is available. The microscopic properties between the particles such as the coefficients of rolling (µr) and sliding (µs), are numerically determined in two different ways: with and without considering the fluid effect. In an earlier study, the microscopic properties were determined by discrete element method (DEM) and without considering the air effect on the macroscopic properties such as the Angle of Repose. The purpose of this paper is to recalibrate the microscopic properties through a coupling between the DEM and computational fluid dynamics (CFD).Design/methodology/approach– The first step is dedicated to the calibration of the CFD-DEM model through modelling a single particle sedimentation within air, water, and silicon oil. The voidage and drag models, the grid size ratio (D/dx), the domain size ratio (W/D), and the optimum coupling interv...
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The Internet of Things and Big data these days means big business. Monitoring Belt Conveyor Systems used to be performed by means of inspectors and off line. These days the developments are towards fully automated inspection systems. The... more
The Internet of Things and Big data these days means big business. Monitoring Belt Conveyor Systems used to be performed by means of inspectors and off line. These days the developments are towards fully automated inspection systems. The IoT enables that more information from sensor systems becomes available that was not available in the past. Theoretically this means that monitoring Belt Conveyor systems 24/7 should become reality and down-time and unexpected maintenance a thing of the past. All these sensor systems produce a vast amount of information. Big data implies a combination of databases too large and/or too diverse to maintain by regular database management systems. Big data plays an ever-increasing role these days. This paper discusses an application of the IoT in bulk solid handling and transportation systems and the utilization of big data. It discusses recent developments and a case study.
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This paper proposes a new mathematical model for predictive scheduling of perishable material transports with the aim of reducing losses of perishable goods. The model is particularly designed for allocation of potatoes from several farms... more
This paper proposes a new mathematical model for predictive scheduling of perishable material transports with the aim of reducing losses of perishable goods. The model is particularly designed for allocation of potatoes from several farms to a nearby starch mill, which produces starch from a limited amount of potatoes each day. Scheduling should determine how much amount of potatoes be sent from which farm to the mill on each day. It is known that the quality of potatoes decreases over time and as a result less starch is produced. A model predictive control approach is proposed to maximize the production of starch. Simulation experiments indicate that predictive scheduling can yield higher starch production compared to non-predictive approaches.
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During the past decade, inland vessels have gained importance in container transport because of their reliability, low environmental impact, and major capacity for increased exploitation. Although inland vessels are crucial in container... more
During the past decade, inland vessels have gained importance in container transport because of their reliability, low environmental impact, and major capacity for increased exploitation. Although inland vessels are crucial in container transport between terminals in the port and the hinterland, in a large seaport like the one in Rotterdam, Netherlands, only 62% of the inland vessels leave the port on time. The other vessels have to stay in the port area for a longer time than planned. This situation leads to uncertainty in waiting times of vessels at terminals and low utilization of terminal quay resources. A two-phase approach is proposed that integrates mixed-integer programming (MIP) and constraint programming (CP) to solve the problem by generating optimal rotation plans for inland vessels. In the first phase, the single-vessel optimization problem is formulated on the basis of MIP and solved with state-of-the-art MIP solvers. In the second phase, the multiple-vessel coordinati...
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This paper presents the use of the Simulation Integrated Design (SID) approach for agribulk terminal design. The SID approach, as a part of the 'Delft Systems approach', applies simulation from the very start of the design... more
This paper presents the use of the Simulation Integrated Design (SID) approach for agribulk terminal design. The SID approach, as a part of the 'Delft Systems approach', applies simulation from the very start of the design process. SID shows that the iterative process of creating and verifying (discrete-event) simulation models enriches the perception of the system (agribulk terminal). The use of SID is illustrated by the development of two simulation models: the Terminal Configuration Model (TCM) and the Terminal Operational Model (TOM). Experiments with TCM enable the design team to investigate strategic design decisions. Possible bottlenecks and unexpected problems can be revealed early on in the design process by using the time dependant behavior of the terminal and using stochastic characteristics, preventing costly adjustments of the design plan in a later stage. Experiments with TOM enable the design team to investigate, in a further developed stage of the design process, control requirements, tactical design decisions and their related process parameters.
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Airports are very important for economic growth. The demand for airport capacity has been growing very fast and private companies are now also investing in airport infrastructure. Airports must however be regulated because they are... more
Airports are very important for economic growth. The demand for airport capacity has been growing very fast and private companies are now also investing in airport infrastructure. Airports must however be regulated because they are natural monopolies with high market power. Airports have variables and factors that are vital for airline operations. The identification of these variables are important to
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This paper examines the effects that low-cost carriers (LCC’s) produce when entering new routes operated only by full-service carriers (FSC’s) and routes operated by low-cost carriers in competition with full-service carriers. A... more
This paper examines the effects that low-cost carriers (LCC’s) produce when entering new routes operated only by full-service carriers (FSC’s) and routes operated by low-cost carriers in competition with full-service carriers. A mathematical model has been developed to determine what routes should be operated by a low-cost carrier with better possibilities to subsist. The proposed model in this paper was
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The invention relates to a recovery vehicle suitable for heavy loads such as an aircraft, comprising a mobile chassis upon which a lifting element is provided and the lifting element comprises an air cushion. The lifting element comprises... more
The invention relates to a recovery vehicle suitable for heavy loads such as an aircraft, comprising a mobile chassis upon which a lifting element is provided and the lifting element comprises an air cushion. The lifting element comprises an adjustable lifting platform and the air cushion is provided on this lifting platform. The height of the lifting platform in relation
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... emulation and prototyping Mark B. Duinkerken, Ashley Nuttall, Jaap A. Ottjes and Gabriel Lodewijks Abstract ... real time, its scheduling capacities can also be used to establish the poll frequencies for the ... be linearized to: d;... more
... emulation and prototyping Mark B. Duinkerken, Ashley Nuttall, Jaap A. Ottjes and Gabriel Lodewijks Abstract ... real time, its scheduling capacities can also be used to establish the poll frequencies for the ... be linearized to: d; =-V-<P, (2) The front (aml) and rear (ana) steering angles ...
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This paper presents a general framework for the application of simulation during the different phases of decision making in production control. Each phase of decision-making requires a different simulation model with different goals and... more
This paper presents a general framework for the application of simulation during the different phases of decision making in production control. Each phase of decision-making requires a different simulation model with different goals and characteristics. The modeler should be aware of these characteristics in order to take full advantage of the use of simulation. The paper shows the decision-making structure and explains the way how simulation could support and improve this. Finally a general framework results with different interacting models, reflecting the decision-making structure of a company.
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A supporting body (1) for an axially moving body such as a conveyor belt, a cable or a stepless escalator, comprising a roller (3) rotatable about a shaft (2) for the support of the body and at least a first support (4) in which the shaft... more
A supporting body (1) for an axially moving body such as a conveyor belt, a cable or a stepless escalator, comprising a roller (3) rotatable about a shaft (2) for the support of the body and at least a first support (4) in which the shaft of the roller is mounted for carrying the roller, wherein a second support is provided, wherein the first support and the second support (5) are designed to cooperate in carrying the roller, wherein the second support is fixedly mounted and the first support can, in the moving body's direction of movement, be fixedly coupled with the second support, while in a plane perpendicular to this direction of movement, the first support is rotatable about a pivoting point located on a contact surface shared by the roller and the body to be supported by the roller.
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Conventional troughed belt conveyors often receive material flows that are smaller than their conveying capacity. DIN 22101 indicates that reducing the belt speed, and thereby maximizing belt load, always results in a reduction of the... more
Conventional troughed belt conveyors often receive material flows that are smaller than their conveying capacity. DIN 22101 indicates that reducing the belt speed, and thereby maximizing belt load, always results in a reduction of the required mechanical and electrical drive power. Predictions of the speed control savings by DIN22101, however, are inaccurate. Therefore power consumption savings can be truly validated only by physical measurements. Several measurements were carried out for validation purposes. With information on speed control savings an evaluation can be made whether the capital expenditures required for speed control conversion are economically feasible. This article provides a methodology to predict these savings with the use of DIN 22101.
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ABSTRACT The application of the rigid ring tyre model, in combination with a new enveloping model with elliptical cams, mounted in a quarter vehicle system is described for both specific obstacles, like potholes and bumps, and measured... more
ABSTRACT The application of the rigid ring tyre model, in combination with a new enveloping model with elliptical cams, mounted in a quarter vehicle system is described for both specific obstacles, like potholes and bumps, and measured road profiles that fit the general category of &#39;&#39;broad-band random signals&#39;&#39;. Validation results of both the tyre and vehicle models are presented. In addition, the models are analysed extensively to obtain insight into how the vehicle system behaves and to investigate how the enveloping model that generates an effective road surface contributes to this behaviour.
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Belt conveyors generally run at designed nominal speed. When material loading rate is smaller than the nominal conveying capacity the belt is under the situation of being partially filled. It provides the potential of reducing energy... more
Belt conveyors generally run at designed nominal speed. When material loading rate is smaller than the nominal conveying capacity the belt is under the situation of being partially filled. It provides the potential of reducing energy consumption by means of adjusting the speed of the belt. For practical reasons discrete control is preferred to adjust the belt speed. This paper presents a fuzzy control method to improve the energy efficiency of large-scale belt conveying systems. Fuzzy logic is applied to represent the change of material loading rate. A fuzzy control algorithm is developed to optimize the adjustment of belt speed to avoid potential material spillage and material overload caused by the short-term material loading peaks. Energy savingsareestimated by computer simulation. Simulation model and outputare verified by practical measurement.
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This book is primarily intended for engineers that reach a managerial position in organisations in the industrial sector (production or transport), public and private services, societies, banks, etc., as well as for members of staff who... more
This book is primarily intended for engineers that reach a managerial position in organisations in the industrial sector (production or transport), public and private services, societies, banks, etc., as well as for members of staff who support these functions. In addition, this book is also intended for engineering students who aspire to a managerial or staff position in the future. Whenever we use the word “manager”, we specifically address the engineer who performs a managing function. 1.1 The Purpose of this Book The purpose of this book is as follows: • To improve the conception of a design in order to obtain a better match between the expected operation and the real operation of an (intended) industrial system. • To integrate the structural and behavioural conceptions of a system to be designed. • To support communication between different specialists, both of whom are involved in the same processes and projects. • To guide managers in their application of this knowledge to th...
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Transportation of perishables such as fruits and vegetables with short shelf life in international, long distance and cooled condition, plays a key role in global cold chains. Compared with truck transportation, intermodal transportation... more
Transportation of perishables such as fruits and vegetables with short shelf life in international, long distance and cooled condition, plays a key role in global cold chains. Compared with truck transportation, intermodal transportation largely reduces logistics cost and emissions, however, has less flexibility for disturbances. Another aspect is that truck transportation occupies the largest share in inland transportation, which causes traffic congestion and environmental pollutions. Synchromodal transportation is a known method to study the effectiveness, efficiency and sustainability of transportation by using real-time information. However, limited articles can be found about the cold chain perspective, an integral analysis is missing. Our objective is to thoroughly analyze the characteristics and challenges of synchromodal transportation in global cold chains. The critical successful factors are analyzed at first. After that, we survey on planning problems in strategic, tactical and operational level, respectively. Finally, we conclude by suggesting further research directions.
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In this paper, we proposed a new approach for the anti-sway control of container cranes. The container crane modeled as a hybrid PDE-ODE system with flexible cable. The dynamics of the moving system is derived as a cable with tension... more
In this paper, we proposed a new approach for the anti-sway control of container cranes. The container crane modeled as a hybrid PDE-ODE system with flexible cable. The dynamics of the moving system is derived as a cable with tension caused payload using Hamilton's principle for the systems. The control objective is to suppress the transverse vibrations of the crane via boundary control. A control law based upon the Lyapunov's second method is derived. It is revealed that a time-varying control force and a suitable passive damping at the actuator can successfully suppress the transverse vibrations. The exponential stability of the closed loop system is proved. The effectiveness of the control laws proposed is demonstrated via simulations.
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Abstract A robotic mobile fulfillment system (RMFS) is a “parts-to-picker” system employing a fleet of autonomous vehicles (AV), which transport pods between a storage area and picking stations. In this paper, an AV interference-free... more
Abstract A robotic mobile fulfillment system (RMFS) is a “parts-to-picker” system employing a fleet of autonomous vehicles (AV), which transport pods between a storage area and picking stations. In this paper, an AV interference-free scheduling on bidirectional paths (IFSB) approach is studied and shows better working efficiency than unidirectional paths. In order to model AV scheduling on bidirectional path with interference-free constraints, a no-wait flexible process job shop scheduling problem (NWFPJSP) is employed to evaluate total completion time. A mathematical model aiming to minimize the total completion time is presented with as constraint interference-free operation. An A* algorithm is modified for path planning and a simulated annealing algorithm (SA) is employed for scheduling AVs and their paths. Based on a case study with a small RMFS, the IFSB approach results in a 40% increase of the storage capacity and a 22% decrease of the total completion time when compared to a unidirectional approach. Meanwhile, the number of AVs stop-starts are decreased by 40% and the paths length for all AV are decreased by 36%. This indicates the great potential of bidirectional paths in future logistic applications, which may increase the storage capacity, working efficiency, technical health of the AVs, and environmental sustainability.
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The ultimate strength of metallic pipelines will be inevitably affected when they have suffered from structural damage after mechanical interference. The present experiments aim to investigate the residual ultimate bending strength of... more
The ultimate strength of metallic pipelines will be inevitably affected when they have suffered from structural damage after mechanical interference. The present experiments aim to investigate the residual ultimate bending strength of metallic pipes with structural damage based on large-scale pipe tests. Artificial damage, such as a dent, metal loss, a crack, and combinations thereof, is introduced to the pipe surface in advance. Four-point bending tests are performed to investigate the structural behavior of metallic pipes in terms of bending moment–curvature diagrams, failure modes, bending capacity, and critical bending curvatures. Test results show that the occurrence of structural damage on the pipe compression side reduces the bending capacity significantly. Only a slight effect has been observed for pipes with damage on the tensile side as long as no fracture failure appears. The possible causes that have introduced experimental errors are presented and discussed. The test da...
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This paper presents an improved zero vibration method for the swing control of bridge-type grab ship unloader. With the method, the concepts of equivalent frequency and the equivalent damping ratio are proposed to cope with the changeable... more
This paper presents an improved zero vibration method for the swing control of bridge-type grab ship unloader. With the method, the concepts of equivalent frequency and the equivalent damping ratio are proposed to cope with the changeable length of rope, and the optimal path planning is considered to avoid collision and improve efficiency. Numerical simulation results of a case study indicate that the maximum residual swing angle of the grab can be limited to a small range to ensure safety using the improved zero vibration method, whereas the traditional zero vibration method with average frequency and zero damping ratio gets poor results of swing control. After that, the sensitivities of the max residual swing angle to the changes of some main design parameters (damping coefficient, deviation of the center of gravity of the grab in rope direction, and time delay of the system) and operating parameters (position deviation of the trolley, initial length deviation of the rope, and ini...
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Condition monitoring systems are commonly exploited to assess the health status of equipment. A fundamental part of any condition monitoring system is data acquisition. Meaningfully estimating the current condition and predicting the... more
Condition monitoring systems are commonly exploited to assess the health status of equipment. A fundamental part of any condition monitoring system is data acquisition. Meaningfully estimating the current condition and predicting the future behaviour of the equipment strongly depend on the characteristic of the data measurement stage. Nowadays, condition monitoring has wide applications in the railway industry, and various monitoring approaches have been proposed for the inspection of wheel and rail conditions. In-service condition monitoring of wheels provides the real-time data required for maintenance planning, while in-workshop inspection is normally done at fixed intervals carried out periodically. In-service data acquisition can be divided into on-board and wayside measurements. In this paper, on the basis of these classifications, the existing data acquisition techniques for the monitoring of railway wheel condition are reviewed, and the state-of-the-art methods and required ...