The paper presents an analytical model for travel time evaluation in double-deep, triple-deep, quadruple-deep and fivefold-deep tier-captive shuttle-based storage and retrieval system (SBS/RS). Under ...the assumption of the deepest location rule for the storage process and the nearest neighbour rule for the retrieval process, the expressions for single-command and dual-command cycle times of the shuttle vehicle and elevator are developed, from which the SBS/RS performance can be estimated. The model based on the probability theory enables the evaluation of all individual times that make up the cycle times and assessment of the average number of totes relocated during a retrieval process. Special attention is devoted to the modelling of the relocation of totes which block access to the requested tote during the retrieval process. The validity of the analytical model is examined via the developed simulation model. The given case study shows that the proposed analytical travel time model results match the results of the simulation model. The presented modelling strategy could be applied to bigger system racking depths following the same modelling logic.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
This paper aims at the identification and assessment of High-Impact Research Papers (HIRPs) on the Berth Allocation Problem (BAP) research at marine terminals. The BAP objective is to optimally ...assign and schedule ships at berthing positions along a quay, as well as to determine the berthing times and positions of ships at a port. The purpose of this study is to facilitate the work of the relevant research community and ultimately promote the research quality in this area. In meeting this objective, the paper utilizes a systematic and fair method to determine HIRPs of the BAP, which is based on the h-index and the g-index. An in-depth bibliometric analysis of the identified studies reveals their key features and characteristics. The analysis was conducted using the VOSviewer and bibliometrix R-package software programs. The main findings provide many useful insights on the BAP research development. The adopted approach and associated analysis results present an up-to-date detailed picture of the BAP research and constitute a valuable tool for its applications into other relevant research areas. The common trends in the reviewed HIRPs and important future research needs are discussed in a comprehensive manner. This survey study can be viewed as the first attempt for a comprehensive bibliometric survey of the high-impact BAP literature, which will be of a great value to researchers and industry practitioners. Furthermore, the proposed methodology for the identification of HIRPs can be used not only for the BAP research but for the literature surveys in other domains as well.
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•A comprehensive analysis is conducted for the Berth Allocation Problem (BAP) research.•High Impact Research Papers (HIRPs) in the BAP research are identified and analyzed.•The co-authorship relations among countries, institutes, and authors are investigated.•Trending models of HIRPs and their solution techniques are discussed.•The statistical techniques for mapping and network analysis of HIRPs are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Intermodal freight transportation refers to a multi-modal chain of container-transportation services which usually links the initial shipper to the final consignee of the container (door-to-door ...service) and takes place over long distances. Container transportation is a major component of intermodal transportation and international commerce. Container flow should be optimal to ensure proper resource utilization and profitability to players. Various multi-objective evolutionary algorithms have been developed to efficiently solve optimization problems in container flows. This paper presents a short review of optimization problems in intermodal transport using sea and land legs together regarding three mostly observed objectives (transport cost, transit time and CO2 emissions).
The aim of this research is to study the dynamic behaviour of a real gantry crane subjected to the actions induced by the trolley and payload movement. A specific numerical procedure was developed ...and implemented in the finite element method in order to simulate different trolley movement modes on the crane's main beam. From the results, it is clear that the crane displacement, especially the longitudinal one, is strongly dependent on the acceleration both in the starting phase and in the stopping phase to which the trolley is subjected during its movement on the crane main beam. The last part of this research simulates the sudden stop of the trolley movement and subsequent payload swinging; in this case, the length of the rope that suspend the payload to the trolley has a fundamental role in the trend and maximum longitudinal crane displacement value.
We discuss dynamic system performance evaluation in the river port utilizing queuing models with batch arrivals. The general models of the system are developed. This system is modelled by MX/M/n/m ...queue with finite waiting areas and identical and independent cargo-handling capacities. The models are considered with whole and part batch acceptance (or whole and part batch rejections) and the interarrival and service times are exponentially distributed. Results related to the batch blocking probability and the blocking probability of an arbitrary vessel in nonstationary and stationary states have been obtained. Numerical results and computational experiments are reported to evaluate the efficiency of the models for the real system.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The evolution of belt conveyors, as an important type of continuous conveying machinery, is examined here in a historical perspective. For this purpose, the selected period is from the ancient time, ...i.e. occurrence of conveying equipment, and up to the end of the nineteenth century. The basic postulation of a modern machine, including conveyors, is often interlinked to that of its ancestor, which may be simple and primitive. Ancient machines and principles of their work were the basis for later improvements which also brought the inventions in engineering. For instance, Archimedes lifted water to high altitude with a screw, which was regarded as the ancestor of today’s screw conveyor and essentially his design has not changed since then. Bucket elevators also have their predecessors dating back to ancient times. In the concrete case of belt conveyors, a first trace can be found in the beginning of the seventeenth century, even classified as primitive example. During the Industrial Revolutions, various machines, such conveyors, appeared. The first modern-like belt conveyors are dedicated to the late eighteenth century due to the invention of Oliver Evans in USA and to the nineteenth century, by Lyster in England, Lopatine in Russia and Thomas Robins in USA. The technical solutions developed by the end of the nineteenth century were forerunners of the today’s belt conveyors, while the key operational principles have not changed.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Tie-rods are vital parts of the bucket wheel excavator slewing superstructure.•Experimental and numerical investigations are carried out on the eyebar model.•Plastification occurs across the full ...width of the cross-section near the hole.•DIN yields the results much lower than the actual stress values around the opening.•Nevertheless, DIN criterion is sufficient for the preservation of the eye integrity.
Tie-rods of the bucket wheel and counterweight booms are vital parts of the bucket wheel excavator slewing superstructure. This paper is dedicated to the problem of identifying the stress state of the critical cross-section ('net section') of the eye plates on these tie-rods. It presents the results of the experimental and numerical investigations carried out on the eyebar model. The results show the appearance of a plastic deformation in the zone near the contour of the hole even when the eye is subjected to the loads within the range of the permissible loads prescribed by the standard DIN 22261-2. Plastification in the eye net section occurs across the full thickness of the plate, but it does not jeopardize the integrity of the structure. The stress value in the eye net section, calculated in accordance with the standard DIN 22261-2, is significantly lower than the actual stress values around the hole and serves only as a comparative value for the static strength proof for the eye.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Liner shipping is the most efficient mode of transport for goods. International liner shipping is a sophisticated network of regularly scheduled services that transports goods from anywhere in the ...world to anywhere in the world at low cost and with greater energy efficiency than any other form of international transportation. Liner shipping connects countries, markets, businesses and people, allowing them to buy and sell goods on a scale not previously possible. Today, the liner shipping industry transports goods representing approximately one-third of the total value of global trade. Ocean shipping contributes significantly to international stability and security. Considering the large and constant struggle in the market in terms of competitive pricing of products, a very important and indispensable role represents the container transport with a clear task to define the final price of the product. This paper analyzes the costs of container transport flow between Far East and Serbia, using different liner shipping services, observing the six world’s largest container operators (Maersk Line, Mediterranean Shipping Company, CMA CGM, Evergreen Line, China Ocean Shipping Company and Hapag-Lloyd) and inland (truck-rail-river) transport corridors. These corridors include distance between selected Mediterranean ports (Koper, Rijeka, Bar, Thessaloniki, Constanta) and Serbia. As a result, in this paper is considered a mathematical model that provides a comparative analysis of transportation costs on the different routes. It is observed already existing transport routes and it is also given hypothetical review to the development of new transport routes. The main goal of this research is to provide an optimal route with lowest transportation cost during container transport. Selection of the best route in the intermodal network is a very difficult and complex task. The costs in all modes of transport and the quality of their services are not constant parameters and changes depending on a number of conditions and characteristics. The analysis of this model within combined maritime and land-based networks would prove helpful for the study of logistics chains, the hinterland-foreland continuum, intermodal transport systems, and market competitiveness.
PurposeThe paper undertakes a bibliometric analysis and assessment of journal publications in the field of container terminal operations research (CTOR), in an attempt to identify high-impact papers ...(HIPs) published in Science Citation Index/Social Science Citation Index (SCI/SSCI) journals of CTOR subject category from 1973 to 2020.Design/methodology/approachA structured approach for identifying the HIPs is developed based on the utilization of bibliometric and network analyses.FindingsThe CTOR papers are assessed in terms of publication outputs, distribution of outputs in SCI/SSCI journals, authorship, institutions and countries, as well as citation life cycles of papers with the highest total citations since their publication until the year 2020. The results show that between 1989 and 2015, there were 82 HIPs in the field of CTOR, which have been cited at least 200 times, with more than 50% of these citations allocated in the second part of paper citation life cycle according to the database of Google Scholar.Practical implicationsThe practical implication of the aforementioned reviewing and assessing journal publications of CTOR is that it offers the ability to reveal the tone of its development through addressing main characteristics of the relevant HIPs as determined by the highly cited papers in this field of research.Originality/valueThis paper offers a unique analysis and assessment in the field of CTOR by identifying the relevant HIPs and their associated scientific actors (authors, institutions and countries), thus facilitating the future research effort in the field of CTOR.
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The analysis of behaviour of extended one-sided stiffened bolted end-plate moment connection is revisited here. On the basis of experimental tests, the behaviour of beam-to-column ...joint with and without stiffener is investigated. The stress distribution and deformation characteristics were determined and discussed with corresponding results of finite element analysis of joint behaviour. Furthermore, the extensive finite element simulations were carried out and the obtained results are discussed in this paper. The main analyzed parameters are the geometrical characteristics of the plates added to the beam-to-column joint. Their influence on joint resistance and stiffness is observed including the possibility of material cost optimization. Overall, the comparison of used approaches confirms their conjoint importance except for the postulation where the stiffener is assumed to behave as a strut in the joint. Also, there are some practical recommendations in design which can be used by engineers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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