scholarly journals Resource Capacity Requirement for Multi-Terminal Cooperation in Container Ports

2021 ◽  
Vol 11 (19) ◽  
pp. 9156
Author(s):  
Byung Kwon Lee ◽  
Joyce M. W. Low

Capacity sharing among neighboring terminals offer a means to meet increasing or unexpected demand for cargo-handling without additional capital investment. This study proposes a model for capacity requirement planning of major resources, such as quay cranes (QCs), storage space, and gate, in multiterminal port operations where demand is time dependent. A resource profile simulation is run to generate random events across the terminals and estimate the capacity requirement in the form of workload distributions on port resources over time-shifts. The effects on workload requirement, arising from multiterminal cooperation, are subsequently evaluated in consideration of different container flows among terminals. Experimental results suggest that higher transferring rate between terminals will reduce the QC intensity and storage space requirements but increase gate congestion. Variabilities in the QC intensity and storage space requirements also increase due to shorter stays and more movements in container inventory at the yard. The interaction effect between transferring and trans-shipment rates further shows that the average resource requirements for a terminal can be greatly reduced when the interterminal transferring of containers contributes positively to a more even workload redistribution across terminals. The most significant improvements occur when trans-shipment rate is 85% and transferring rate is 75% for QC intensity; trans-shipment rate is 90% and transferring rate is 60% for storage capacity; and trans-shipment rate is 80% and transferring rate is 75% for gate congestion.

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Qing An ◽  
Jun Zhang ◽  
Xin Li ◽  
Xiaobing Mao ◽  
Yulong Feng ◽  
...  

The economical/environmental scheduling problem (EESP) of the ship integrated energy system (SIES) has high computational complexity, which includes more than one optimization objective, various types of constraints, and frequently fluctuated load demand. Therefore, the intelligent scheduling strategies cannot be applied to the ship energy management system (SEMS) online, which has limited computing power and storage space. Aiming at realizing green computing on SEMS, in this paper a typical SIES-EESP optimization model is built, considering the form of decision vectors, the economical/environmental optimization objectives, and various types of real-world constraints of the SIES. Based on the complexity of SIES-EESPs, a two-stage offline-to-online multiobjective optimization strategy for SIES-EESP is proposed, which transfers part of the energy dispatch online computing task to the offline high-performance computer systems. The specific constraints handling methods are designed to reduce both continuous and discrete constraints violations of SIES-EESPs. Then, an establishment method of energy scheduling scheme-base is proposed. By using the big data offline, the economical/environmental scheduling solutions of a typical year can be obtained and stored with more computing resources and operation time on land. Thereafter, a short-term multiobjective offline-to-online optimization approach by SEMS is considered, with the application of multiobjective evolutionary algorithm (MOEA) and typical schemes corresponding to the actual SIES-EESPs. Simulation results show that the proposed strategy can obtain enough feasible Pareto solutions in a shorter time and get well-distributed Pareto sets with better convergence performance, which can well adapt to the features of real-world SIES-EESPs and save plenty of operation time and storage space for the SEMS.


2020 ◽  
Vol 38 (1B) ◽  
pp. 15-25
Author(s):  
Ali A. Hussain ◽  
Rehab F. Hassan

Spatial indexes, such as those based on the Quad Tree, are important in spatial databases for the effective implementation of queries with spatial constraints, especially when queries involve spatial links. The quaternary trees are a very interesting subject, given the fact that they give the ability to solve problems in a way that focuses only on the important areas with the highest density of information. Nevertheless, it is not without the disadvantages because the search process in the quad tree suffers from the problem of repetition when reaching the terminal node and return to the behavior of another way in the search and lead to the absorption of large amounts of time and storage. In this paper, the quad tree was improved by combining it with one of the space filling curve types, resulting in reduced storage space requirements and improved implementation time


2018 ◽  
Vol 2 ◽  
pp. e28197
Author(s):  
Kelsey Falquero ◽  
Katherine Roberts ◽  
Jessica Nakano

Q?rius is an interactive learning venue at the Smithsonian National Museum of Natural History (NMNH) designed specifically for a teen audience. The space gives visitors a chance to interact with museum specimens, especially in the Collections Zone. The Q?rius collections are non-accessioned education collections, belonging to the Office of Education and Outreach (E&O). The collections include the Museum’s seven disciplines – Anthropology, Botany, Entomology, Invertebrate Zoology, Mineral Sciences, Paleobiology, and Vertebrate Zoology. Starting in 2013, collections staff began performing safety assessments on specimens before their rehousing and storage in the publicly accessible Collections Zone. Risks assessed include sharpness, ingestibility, radioactivity, and contaminants (such as arsenic, mercury, and lead, which were historically used in specimen preparation or for pest management). Specimen and object fragility was also assessed. The goal of these assessments was to minimize risks to our visitors and to our collections. The safety assessments allow collections staff to make housing recommendations that would ensure the safety of NMNH’s visitors and the preservation of E&O’s collections in a publicly accessible storage space. This practice now extends to other pre-existing learning venues that contain publicly accessible portions of the E&O Collection, further minimizing risks. Staff have started adding the data gathered by these safety assessments to our collections management system, to protect the data from loss and to make the information easily accessible to staff. This poster relates to a second poster, Establishing Legal Title for Non-Accessioned Collections.


Author(s):  
Jorge Loureiro ◽  
Orlando Belo

OLAP queries are characterized by short answering times. Materialized cube views, a pre-aggregation and storage of group-by values, are one of the possible answers to that condition. However, if all possible views were computed and stored, the amount of necessary materializing time and storage space would be huge. Selecting the most beneficial set, based on the profile of the queries and observing some constraints as materializing space and maintenance time, a problem denoted as cube views selection problem, is the condition for an effective OLAP system, with a variety of solutions for centralized approaches. When a distributed OLAP architecture is considered, the problem gets bigger, as we must deal with another dimension—space. Besides the problem of the selection of multidimensional structures, there’s now a node allocation one; both are a condition for performance. This chapter focuses on distributed OLAP systems, recently introduced, proposing evolutionary algorithms for the selection and allocation of the distributed OLAP Cube, using a distributed linear cost model. This model uses an extended aggregation lattice as framework to capture the distributed semantics, and introduces processing nodes’ power and real communication costs parameters, allowing the estimation of query and maintenance costs in time units. Moreover, as we have an OLAP environment, whit several nodes, we will have parallel processing and then, the evaluation of the fitness of evolutionary solutions is based on cost estimation algorithms that simulate the execution of parallel tasks, using time units as cost metric.


2014 ◽  
Vol 507 ◽  
pp. 7-10
Author(s):  
Da Ke Wei ◽  
Hong Jin ◽  
Hong Yuan Mei

This study focuses on the internal layout of premises of UKs day care unit for older people, including possible combinations of rooms and spaces, access and circulation. All day units require a minimum of a dining/activity space, a kitchen, (a) toilet (s) and storage space, these rooms and spaces are combined into the basic type of premises. Depending on the aims of the unit, the number of places provided, and users' needs, many of the disadvantages associated with basic premises can be overcome if the premises have extra spaces. From the above analysis we can see that, in existing day unit premises, the number and type of rooms and spaces and how they are grouped together vary considerably, ranging from simple to complex arrangements. Also, the relationships between rooms and spaces in layouts for all day unit premises need to be pondered over, including distances between key rooms/spaces, the relative location of spaces in terms of their functions, the relationship between private and public spaces and the views within and between rooms, and from external windows. In addition, access and circulation of a day unit need to be considered carefully, including access to the day unit premises and the reception space and internal circulation.


2012 ◽  
Vol 48 (No. 8) ◽  
pp. 347-352
Author(s):  
M. Vicen ◽  
I. Ubrežiová

The analysis is made in the set of the selected foodstuffs wholesales in the Slovak Republic and shows their differences from the viewpoint of the size (sale place 15 m2–1 300 m2 , storage space 106 m2–6 500 m2 ), number of workers (1–81) and yearly turnover (219 thousand SKK–2 748 thousand SKK). The main part of wholesales is operated by owners (83%) and a small part (17%) is on lease. From the viewpoint of location, the wholesales are situated in the centre of town (50%) and village (27%). The rest is located in the habitations and suburbs of town. The competitive wholesales (43%) are situated in the distance from 11 to 500 m. The highest labour productivity was obtained at the wholesale with location in the suburbs of town and the distance from competitive firms is about 500–1 000 m. Suitable results were achieved in the wholesales on lease with location in the suburbs of towns. The efficiency of wholesales was affected by the main factors, including the number of workers, size of sale place and storage space which determined up to the 92% of the volume of yearly turnover.


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