scholarly journals Cooperative Scheduling of AGV and ASC in Automation Container Terminal Relay Operation Mode

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Qinglei Zhang ◽  
Weixin Hu ◽  
Jianguo Duan ◽  
Jiyun Qin
Keyword(s):  
Waiting Time ◽  
Large Scale ◽  
Buffer Capacity ◽  
Container Terminal ◽  
Operation Mode ◽  
Buffer Zone ◽  
Buffer Zones ◽  
Collaborative Scheduling ◽  
Automated Container Terminal ◽  
Time Buffer

The key problem of operation optimization for automated container terminal is the coordinated scheduling of automated quay crane (QC), automated guided vehicle (AGV), and automated stacking crane (ASC). In order to solve this problem, this paper proposed a new method to optimize the scheduling of ASC and AGV. In the automated container terminal, each container block is equipped with twin ASCs. At the same time, buffer zones are set at both ends of the container block to achieve the decoupling operation among ASC, AGV, and container truck. Considering the buffer capacity constraint and twin ASC operation interference, and introducing the design of handshake area, this paper developed a collaborative scheduling model of AGV and ASC in automatic terminal relay operation mode. This model is designed based on the genetic algorithm. The model aims to minimize the AGV waiting time and the ASC running time. The results indicated that the introduction of handshake area can effectively reduce the ASC operation interference by 10.56% on average. Also, it can be found that increasing buffer capacity can reduce the waiting time of AGV by about 4.25% on average, and the effect of relay operation is more obvious in large-scale operation. It was proved that buffer zone and handshake area can reduce task delay time and improve coordination between AGV and ASC.

An Investigation into Sidings Allocation Strategy for Automated Container Terminal Based on A* Search Algorithm

2012 ◽  
Vol 472-475 ◽  
pp. 526-532
Author(s):  
Wei Yan ◽  
Yuan Jiang ◽  
Jun Liang He
Keyword(s):  
Waiting Time ◽  
Search Algorithm ◽  
Container Terminal ◽  
Rolling Horizon ◽  
Optimal Solutions ◽  
Dynamic Allocation ◽  
Allocation Strategy ◽  
Actual Case ◽  
Allocation Model ◽  
Automated Container Terminal

A rolling-horizon approach was proposed, which aims at the problem of sidings allocation for automated container yard stacking system designed and invented by ZPMC. The dynamic allocation model using objective programming was initially developed for sidings allocation. The model objective function was subject to the minimization of the total job waiting time. Furthermore A* search algorithm was employed for solving the model, which can return optimal solutions. Finally an actual case was firstly studied to illustrate the proposed approach for sidings allocation strategy, and then verified the validity and usefulness of this model and algorithm.

scholarly journals Noisy Optimization of Dispatching Policy for the Cranes at the Storage Yard in an Automated Container Terminal

2021 ◽  
Vol 11 (15) ◽  
pp. 6922
Author(s):  
Jeongmin Kim ◽  
Ellen J. Hong ◽  
Youngjee Yang ◽  
Kwang Ryel Ryu
Keyword(s):  
Container Terminal ◽  
Scoring Function ◽  
Weight Vector ◽  
Container Terminals ◽  
Exploration And Exploitation ◽  
Noisy Optimization ◽  
Automated Container Terminal ◽  
Simulation Based ◽  
The Cost ◽  
Operation Schedule

In this paper, we claim that the operation schedule of automated stacking cranes (ASC) in the storage yard of automated container terminals can be built effectively and efficiently by using a crane dispatching policy, and propose a noisy optimization algorithm named N-RTS that can derive such a policy efficiently. To select a job for an ASC, our dispatching policy uses a multi-criteria scoring function to calculate the score of each candidate job using a weighted summation of the evaluations in those criteria. As the calculated score depends on the respective weights of these criteria, and thus a different weight vector gives rise to a different best candidate, a weight vector can be deemed as a policy. A good weight vector, or policy, can be found by a simulation-based search where a candidate policy is evaluated through a computationally expensive simulation of applying the policy to some operation scenarios. We may simplify the simulation to save time but at the cost of sacrificing the evaluation accuracy. N-RTS copes with this dilemma by maintaining a good balance between exploration and exploitation. Experimental results show that the policy derived by N-RTS outperforms other ASC scheduling methods. We also conducted additional experiments using some benchmark functions to validate the performance of N-RTS.

scholarly journals Truck Appointment System for Cooperation between the Transport Companies and the Terminal Operator at Container Terminals

2020 ◽  
Vol 11 (1) ◽  
pp. 168
Author(s):  
Hyeonu Im ◽  
Jiwon Yu ◽  
Chulung Lee
Keyword(s):  
Large Scale ◽  
Container Terminal ◽  
Container Terminals ◽  
The Past ◽  
Cooperation Model ◽  
Appointment System ◽  
New Form ◽  
Truck Appointment System ◽  
Import Container ◽  
Very High

Despite the number of sailings canceled in the past few months, as demand has increased, the utilization of ships has become very high, resulting in sudden peaks of activity at the import container terminals. Ship-to-ship operations and yard activity at the container terminals are at their peak and starting to affect land operations on truck arrivals and departures. In response, a Truck Appointment System (TAS) has been developed to mitigate truck congestion that occurs between the gate and the yard of the container terminal. The vehicle booking system is developed and operated in-house at large-scale container terminals, but efficiency is low due to frequent truck schedule changes by the transport companies (forwarders). In this paper, we propose a new form of TAS in which the transport companies and the terminal operator cooperate. Numerical experiments show that the efficiency of the cooperation model is better by comparing the case where the transport company (forwarder) and the terminal operator make their own decision and the case where they cooperate. The cooperation model shows higher efficiency as there are more competing transport companies (forwarders) and more segmented tasks a truck can reserve.

scholarly journals Quantitative Evaluation of China’s Pork Industry Policy: A PMC Index Model Approach

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 86
Author(s):  
Youzhu Li ◽  
Rui He ◽  
Jinsi Liu ◽  
Chongguang Li ◽  
Jason Xiong
Keyword(s):  
Low Income ◽  
Quantitative Research ◽  
Large Scale ◽  
Industrial Structure ◽  
Central Government ◽  
Operation Mode ◽  
Control Policy ◽  
Price Control ◽  
Price Regulation ◽  
Index Model

To ease the fluctuation of hog prices and maintain the hog market’s stability, the central government of China has issued a series of hog price control policies. This paper, supplemented by co-word analysis and LDA thematic modeling, constructed 9 first-level indicators and 36 s-level indicators and used a PMC index model to conduct quantitative research on the selected 74 policies and regulations of China’s pig price regulation policies from July 2007 to April 2020. The research concludes that the research tool system of China’s hog price control is formed. The overall design of the hog price control policy is relatively reasonable, but there are still the following problems: the subject of China’s pig price control policy is singular, so it is difficult to form a resultant force; the policy pays attention to the price regulation in the short term, but ignores the long-term industrial structure adjustment; it emphasizes market supervision, but insufficient support for slaughtering and processing; it focuses on production and management to improve the development quality and efficiency of the pig industry, but does not take social equity into account. Finally, some policy suggestions are put forward: multi-department division of labor and close cooperation; adjusting the industrial structure of hog and carrying out appropriate large-scale breeding; establishing the operation mode of slaughtering and processing in the producing area to reduce the circulation cost of the pig industry; ensuring the consumption of pork by low-income groups and giving consideration to social efficiency and equity.

Optimal berth allocation under regular and emergent vessel arrivals

2020 ◽  
pp. 147509022093788
Author(s):  
Abbas Al-Refaie ◽  
Hala Abedalqader
Keyword(s):  
Waiting Time ◽  
Container Terminal ◽  
Allocation Problem ◽  
Container Terminals ◽  
Future Research ◽  
Satisfaction Level ◽  
Berth Allocation ◽  
Scheduling Problems ◽  
Berth Allocation Problem ◽  
Quay Crane Assignment

This research proposes two optimization models to deal with the berth allocation problem. The first model considers the berth allocation problem under regular vessel arrivals to minimize the flow time of vessels in the marine container terminal, minimize the tardiness penalty costs, and maximize the satisfaction level of vessels’ operators on preferred times of departure. The second model optimizes the berth allocation problem under emergency conditions by maximizing the number of assigned vessels, minimizing the vessel’s waiting time, and maximizing the satisfaction level on the served ships. Two real examples are provided for model illustration under regular and emergent vessel arrivals. Results show that the proposed models effectively provide optimal vessel scheduling in the terminal, reduce costs at an acceptable satisfaction level of vessels’ operators, decrease the waiting time of vessels, and shorten the delay in departures under both regular and emergent vessel arrivals. In conclusion, the proposed models may provide valuable assistance to decision-makers in marine container terminals on determining optimal berth allocation under daily and emergency vessel arrivals. Future research considers quay crane assignment and scheduling problems.

A New Memetic Approach to Solve the Strategic Berth Template Problem

2021 ◽  
Vol 12 (3) ◽  
pp. 212-231
Author(s):  
Issam El Hammouti ◽  
Azza Lajjam ◽  
Mohamed El Merouani
Keyword(s):  
Large Scale ◽  
Container Terminal ◽  
Mathematical Formulation ◽  
Population Based ◽  
Allocation Problem ◽  
Computational Time ◽  
Berth Allocation ◽  
Berth Allocation Problem ◽  
Simulating Annealing ◽  
Annealing Algorithm

The berth allocation problem is one of the main concerns of port operators at a container terminal. In this paper, the authors study the berth allocation problem at the strategic level commonly known as the strategic berth template problem (SBTP). This problem aims to find the best berth template for a set of calling ships accepted to be served at the port. At strategic level, port operator can reject some ships to be served for avoid congestion. Since the computational complexity of the mathematical formulation proposed for SBTP, solution approaches presented so far for the problem are limited especially at level of large-scale instances. In order to find high quality solutions with a short computational time, this work proposes a population based memetic algorithm which combine a first-come-first-served (FCFS) technique, two genetics operators, and a simulating annealing algorithm. Different computational experiences and comparisons against the best known solutions so far have been presented to show the performance and effectiveness of the proposed method.

scholarly journals HiBuffer: Buffer Analysis of 10-Million-Scale Spatial Data in Real Time

2018 ◽  
Vol 7 (12) ◽  
pp. 467 ◽  
Author(s):  
Mengyu Ma ◽  
Ye Wu ◽  
Wenze Luo ◽  
Luo Chen ◽  
Jun Li ◽  
...  
Keyword(s):  
Real Time ◽  
Spatial Data ◽  
High Performance ◽  
Large Scale ◽  
Computation Time ◽  
Buffer Analysis ◽  
Data Volume ◽  
Time Buffer ◽  
Real World Datasets ◽  
Spatial Indexes

Buffer analysis, a fundamental function in a geographic information system (GIS), identifies areas by the surrounding geographic features within a given distance. Real-time buffer analysis for large-scale spatial data remains a challenging problem since the computational scales of conventional data-oriented methods expand rapidly with increasing data volume. In this paper, we introduce HiBuffer, a visualization-oriented model for real-time buffer analysis. An efficient buffer generation method is proposed which introduces spatial indexes and a corresponding query strategy. Buffer results are organized into a tile-pyramid structure to enable stepless zooming. Moreover, a fully optimized hybrid parallel processing architecture is proposed for the real-time buffer analysis of large-scale spatial data. Experiments using real-world datasets show that our approach can reduce computation time by up to several orders of magnitude while preserving superior visualization effects. Additional experiments were conducted to analyze the influence of spatial data density, buffer radius, and request rate on HiBuffer performance, and the results demonstrate the adaptability and stability of HiBuffer. The parallel scalability of HiBuffer was also tested, showing that HiBuffer achieves high performance of parallel acceleration. Experimental results verify that HiBuffer is capable of handling 10-million-scale data.

scholarly journals Housing and population sprawl near tailings storage facilities in the Witwatersrand: 1952 to current

2015 ◽  
Vol Volume 111 (Number 11/12) ◽  
Author(s):  
Melanie A. Kneen ◽  
Matthew E. Ojelede ◽  
Harold J. Annegarn ◽  
◽  
◽  
...  
Keyword(s):  
Census Data ◽  
Buffer Zone ◽  
Housing Development ◽  
Aerial Photographs ◽  
Population Exposure ◽  
Residential Areas ◽  
Gold Extraction ◽  
Buffer Zones ◽  
Quality Dispersion ◽  
Storage Facilities

Abstract Mining, tailings storage facilities (TSFs), dust pollution and growth in residential housing development are synonymous with the Witwatersrand, South Africa. Encroachment of housing onto land close to TSFs, i.e. areas rendered marginal because of the dust hazard and risk of structural failure, has continued unabated for decades, intensifying human exposure to windblown mineral dust. Recent research indicates that the finer milling used for modern gold extraction results in aeolian dust emanating from the TSFs which contributes to a higher proportion of inhalable particles in the source material. Air quality dispersion modelling, validated by ambient aerosol monitoring campaigns, indicates that episodic dust events generate particulate matter (PM10) and, specifically, quartz dust concentrations that are unhealthy at distances of up to 2 km downwind from TSFs. This contribution documented residential development from 1952 to 2011 (using historical aerial photographs, census data from 2001 and 2011 and ancillary information) to determine the population exposed to dust emanations from the TSFs. Using the images, land use was classified into residential areas, TSF footprints and open areas, onto which a series of 500 m buffer zone contours were superimposed. The resulting statistics were used to assess the populations exposed to dust hazard within the defined buffer zones. Overall, housing development has experienced a growth of approximately 700% since 1952 at a rate of 14% per year. Analysis of recent monitoring campaign data has confirmed multiple occurrences of quartzrich inhalable dust in residential settings at levels that exceed occupational health standards, extrapolated to values for population exposure.

scholarly journals Geopolitical Discrimination of Some Countries as Exemplified by Ukraine: Difficulties and Perspectives

2018 ◽  
pp. 666-670
Author(s):  
Olha Bohomolets
Keyword(s):  
United States ◽  
Low Cost ◽  
Geographical Location ◽  
Buffer Zone ◽  
The United States ◽  
Western World ◽  
Collective Security ◽  
Buffer Zones ◽  
International Power ◽  
Post War

The article studies the history and the current stage of Russia’s aggression to-wards countries with lower military potential. The collapse of the post-war system of international relations and collective security has become apparent: the aggression of Russia against Moldova, Georgia and Ukraine has testified to the fact that there are no longer any tools to protect countries subjected to discrimination from super powers. Today discrimination affects not only people or social groups, but also some countries. Such countries are not capable of pursuing an independent policy as to major centres of international power they have to deal with. Peculiar to these countries are uncompetitive economy, low quality of life and undeveloped civil society, they hence become a target for “vital interests”, namely bidding by so-called super powers. “Giants” are attracted by the geographical location of a possible “victim”, access to the sea, transit facilities, natural resources, especially energy, low-cost labour, etc. It is often that “discriminated” countries become grounds for ignition of burning or frozen conflicts provoked by powerful neighbours’ influence, or are exposed to open aggression and become subject to occupation or hybrid war. This has all started after the Second World War, when super powers of the USSR and China, on the one hand, and the United States, Great Britain, Australia, and others, on the other, have made Korea fall into two states. In addition, there was subsequently a division of Germany, the Caribbean crisis…However, such conflicts then were not that wide-ranging, since the post-war collective security system was quite effective. Things, though, have changed dramatically in recent decades. One of the largest global players − Russia – has decisively begun to create around itself a buffer zone formed of countries, where it fuels frozen conflicts and in such a way keeps them under the radar and hinders their integration into the Western world. Initially, Russia ignited a conflict in Nagorno-Karabakh, supporting Armenia and assisting it to invade a considerable part of the territory in Azerbaijan, and then initiated the war in Transnistria by virtually occupying part of Moldova’s territory and asserting itself there on the pretext of deploying a peacekeeping mission. Later, there was a war in Abkhazia and then − in South Ossetia aiming to detach part of Georgia’s territory. And lastly, the turn of Ukraine has come… Regrettably, Ukraine is a typical and another example of a country that has fallen victim of multifaceted interests of the leading global players − Russia, the United States and the EU, and has faced all possible forms of discrimination. Keywords: war in eastern Ukraine, military aggression, geopolitics, conflicts, buffer zones.

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