Demurrage Cost Research Articles

Ship-berth link simulation: impact on total demurrage costs

The ship-berth link is one of the most critical aspects to be managed at port operations. Up to now, simulation models have considered the impact of queue priorities, such as size and type of ships, on waiting times. This paper differentiates from previous studies by considering another variable – the demurrage cost for each type of ship – and the possibility of having different berth allocation policies. It reports on a simulation study carried out on a small Brazilian private container terminal, where different berth allocation policies and queue priorities have been tested. Results indicate that the demurrage cost ratio between large and small ships and the critical waiting time in queue, after which demurrage costs are charged, impact on the choice of most adequate combination of policies and priorities. The analysis presented in this paper may help port authorities in determining a more precise figure for total demurrage costs.

A Comparative analysis of the dispatch cost and demurrage cost according to the berth operating strategy - A Case of Posco -

A Comparative analysis of the dispatch cost and demurrage cost according to the berth operating strategy - A Case of Posco -

인천항 기능 재배치에 따른 갑문의 대기 시뮬레이션 연구

인천항에서는 인천대교 건설을 계기로 남외항 건설을 추진함과 더불어 인천 내항 등의 기능 재배치가 추진되고 있다. 본 논문은 기능 재배치 계획에 따라 2011년과 2015년의 해상교통량을 추정하고, 내항의 갑문 운용에 따른 선박의 대기시간을 항만운용 시뮬레이션에 의하여 분석하여 내항에 기항하는 선박들의 체선 체화비용을 산정 분석하고자 하였으며, 최종적으로 2011년부터 2015년까지 내항에 기항하던 컨테이너선들의 남항/남외항으로의 이전에 따른 경제적 효과를 평가하고자 한다. 주요한 연구결과는 다음과 같다. (1) 갑문 이용율이 약 <TEX>$7\sim8%P$</TEX> 낮아졌다. (2) 갑문 대기시간 및 체선 체화비용이 약 25%P 절감되는 효과가 나타났다. (3) 자문 이용료와 선석 이전에 따른 항로 단축 편익 등을 제외하고 갑문 운용에 따라 발생되는 체선 체화비용은 연간 약 8억원의 절감효과가 있었다. Due to the construction of Incheon Grand Bridge, there is driven a necessity for rearranging the function of Inner Port with the development of Outer South Port. In this paper, I'd like to simulate the port operation levels of Lock Gate in Inner Port with estimating the traffic volumes of 2011 and 2015, which will reveal the Demurrage Cost and the Accumulation Cost of Freight in Inner Port. Finally I will evaluate the economic movement effects of the container ship's calling from Inner port to South Port/Outer South Port from 2011 to 2015. The results are as followings ; (1) The average utilization of Lock Gates are reduced by <TEX>$7\sim8$</TEX> percentage point. (2) The mean queueing value are saved by 25 percentage point. (3) The Demurrage Cost and the Accumulation Cost of Freight except Lock Gate charges and the Benefit of Routeing Reduction are saved about 800 million Won annually.

Rail freight and sustainable urban distribution: Potential and practice

How far can rail freight developments reduce lorry movements and promote sustainable urban distribution when planners discard economically infeasible projects? To expand current dedicated bulk long rail hauls, marginally viable, from Plymouth, UK, potential rail traffics must tap capacity to treble output and cut unit costs. Potentially, aggregated inter-county bulk road movements imply viable train hauls from upgraded railhead facilities. Optimal configurations of enhanced loading, storage and processing facilities and port-railhead links proffer reduced ship demurrage costs with upgraded port handling and relocated petroleum-loading facilities creating employment and further reducing lorry movements. However, in practice, non-viable developments are not sustainable.

인천항 제2연륙교 적정 주경간 폭 결정에 관한 연구 (2) 주경간의 통항방식에 따른 항만운영의 경제성 분석

인천항의 송도 신도시와 영종도 인천국제공항을 이어주는 제2연륙교 건설사업이 1999년 민간제안사업으로 정부에 제안되어 3차례에 걸친 통항 안전성 연구에도 불구하고 적정 교각폭이 결정되지 못하고 있다. 따라서 본 연구에서는 인천항의 제2연륙교 설치시 왕복통항이가능한 교각폭으로 설계한 경우를 대비하여 10,000G/T이상 선박이 일방통항으로 항로폭을 설계할 경우의 항만운용효율 변화 및 경제성을 분석 하고자 한다. 연구결과, 제2연륙교 항로의 왕복통항대비 10,000G/T 이상 일방통항시 제2연륙교 주경간 항로에서의 총대기시간은 2011년도에 20,362시간, 2020년에는 24,544시간으로 평가되었다. 따라서 10,000G/T이상 선박의 일방통항에 따른 체선<TEX>$\cdot$</TEX>체화비용으로 2011년에 약 197억원, 2020년에는 약 233억원이 될 것으로 추정되므로 제2연륙교가 완공될 2008년부터 2040년까지의 33년간의 총 체선<TEX>$\cdot$</TEX>체화비용은 약 7,689억원으로 평가되었다. A construction project of Incheon 2nd bridge, which is connected between the Incheon Song-Do New Town and the Incheon International Airport in Young-Jong-Do, has been proposed by the private capital in 1999. But the optimal width of the main span has not been decided in spite of the three investigations into the feasibility of ship's safe transit in this planned bridge. In this paper, we study the economic analysis on port operational efficiency according to traffic schemes, one-way or two-way of vessels over 10,000G/T, in the main span of this bridge. In this comparative result, total queueing time due to the one-way in the bridge main span is evaluated 20,362 hours in 2011 and 24,544 hours in 2020. Therefore the demurrage cost and the accumulation cost of freight are evaluated 19.7 billion won in 2011, and 23.3 billion won in 2020, then total accumulated costs during 33 years from 2008 until 2040 are evaluated about 768.9 billion won.

Logistics and supply chain strategies in grain exporting

AbstractThe grain shipping industry is highly competitive and has become technically advanced during the past decade. These changes, along with the introduction of innovative shipping mechanisms, have made logistics management an important source of opportunity and risk for grain shippers. A stochastic simulation model was developed to evaluate tradeoffs and effects of key variables on logistical costs in the grain supply chain for an individual firm. Average demurrage for the supply chain was $2.14 million ($0.70/mt or 1.8 cent/bu) with the highest demurrage costs for vessels and lowest for railcars. Of the random variables modeled, unexpected changes in export demand had the greatest impact on costs. [EconLit citation: Q130.] © 2004 Wiley Periodicals, Inc. Agribusiness 20: 449–464, 2004.

DISCRETE TIME PARALLEL-MACHINE SCHEDULING: A CASE OF SHIP SCHEDULING

Parallel-machine scheduling concerns scheduling a number of jobs on more than one processor working in parallel. A medium-term ship scheduling problem frequently encountered in ports is the scheduling of arriving ships so as to minimize the total demurrage cost incurred. This problem is in fact a parallel-machine scheduling problem, and can be formulated as a pure zero-one integer program when time is discrete. Different from the usual parallel-machine scheduling studies, the ready time of each job is not required to be identical. As an illustration, the ship scheduling problem faced by China Steel Corporation in Taiwan is discussed and solved- The proposed model is applicable to other deterministic parallel-machine scheduling problems in which jobs have to be processed continuously on the same or different machines

Coordinated dock operations: Integrating dock arrangement with ship discharging

The operations of material docks involve two major tasks: dock arrangement and ship discharging. The former concerns the sequencing of ships waiting to be berthed for discharging whereas the latter considers the combinations of ship unloaders, conveyors and stackers, so that the total demurrage cost incurred is minimized. Apparently, different arrangements of the docks have different effects on the time required for the subsequent discharging operations. On the other hand, the arrangement of the docks is also affected by the time required for discharging. Hence, a careful coordination of these two tasks is deemed necessary. In this paper an interactive procedure which passes the necessary information between the two subsystems is devised to integrate the two tasks. This procedure is applied successfully to the material docks of the China Steel Corporation. Under complicated situations, the demurrage cost saved is estimated to reach 70%. An example is provided to stress that the performance of the integrated system is better than that of conducting the two tasks independently.

Demurrage costs optimization in ports using binary mathematical programming models

SODA is a system by which the schedule of ships in a port can be found in order to minimize the demurrage and operating costs associated with shipping operations. SODA constructs and resolves binary programming models using shipping data (arrival dates, demurrage costs, berths to be used, etc.) and available berths in a planning horizon. The model is of an adjustable precision: major accuracy implies greater calculation time. SODA provides an optimal result to a complex problem in a resolution time which is generally better than that needed for a manual solution.

Improving Throughput of a Coal Transport System with the Aid of Three Simple Models

The Cape Breton Development Corporation had not been achieving the throughput needed from its transport system for moving coal from its coal storage sites to the shipping piers for loading onto ocean going vessels. We used three simple models to analyze this system and to convince management that it could improve the system dramatically with no capital investment. By following these recommendations, the company has approximately doubled the throughput of this system. This leads to significant savings in vessel demurrage costs and improves the market opportunities for coal sales.

Knowledge-based approach to the optimal dock arrangement

ABSTRACT A problem frequently encountered in ports is the sequencing of waiting ships for berthing to load or unload so that the total demurrage cost incurred is minimized. Here a knowledge-based approach is applied to solve this problem. The constraints of the port and the working rules adopted by the port are expressed as knowledge rules and embedded into the framework of the logic of dock arrangement. With the inference mechanism of a knowledge engineering language OPS5, the best arrangement of the docks can be inferred. Since the operation rules differ from port to port, the problem is confined to the material docks of the China Steel Corporation. A system entitled DOCK is designed to find the best three available alternatives. The idea can be applied and the DOCK system modified for use by other ports.