A capacity study for vessel traffic using automatic identification system data

In this study, we created a simulation model to assess the overall impact of implementing a one-way traffic policy due to construction works. The inputs of the simulation model are found by performing statistical analysis on data from the Automatic Identification System (AIS). The aim of this study is twofold: (a) map the vessel traffic during the reference period and (b) analyse the congestion for the new traffic conditions. We use a non-homogeneous Poisson process with piecewise linear intensity to model the arrival process. For scenarios with varying arrival intensities, we compare the vessels' waiting times as well as the maximum queue lengths. The latter is important for upstream traffic since there are space constraints

Customer's satisfaction at Langkawi ferry terminal

This research was conducted to determine the relationship between the factors that influences and customer’s satisfaction at the Langkawi ferry terminal.There are many issues arising because of several factors.This factor all gives a big impact on Langkawi ferry terminal. The factor is accessibility, facilities, infrastructure, safety and services.The purpose of this study is to determine is it customers’ satisfactions have a relationship with the factors that influences the customers’ after used the product or service provided at the Langkawi ferry terminal.This research paper was conduct base on the Expectancy Disconfirmation Theory (EDT).The respondent was getting from 400 UUM students whom had visited Langkawi.The data were collected via a questionnaire survey targeting respondents who went to Langkawi Terminal, and processed with SPSS v.9 statistical technique descriptive statistics. These study results indicate key customer’s satisfaction in the Langkawi ferry Terminal context, such as facilities, accessibility, infrastructure, service and safety.The survey was constrained by the sample size and cross-section due to the time constraints, more empirical works need to be done to generalize the findings of customer’s satisfaction.This research paper is significant because it helps to identify the customers’ satisfaction at the Langkawi Ferry Terminal

Decision Performance and Safety Performance: A Value-Focused Thinking Study in the Oil Industry

Considerable research has been performed to develop leading indicators of safety performance. We use value-focused thinking to understand the objectives and evaluation measures that frame a particular safety-related decision within an organization. These decisions are part of the safety culture. Our research partners were two oil shipping companies; we surveyed crewmembers on their tankers to evaluate performance in each decision objective on their vessel. We demonstrate that measurements of the achievement of these objectives are related to future safety performance and thus provide leading indicators of safety

SIMULATION OPTIMIZATION OF THE RESOURCES IN TECHNICAL/NAUTICAL SERVICES: SELECTION OF THE PARKING LOCATIONS OF THE TUGBOATS

Suyollarında, kıyı tesislerinde ve açık deniz yapılarında deniz araçlarının manevra emniyeti ve verimliliği için kılavuzluk, römorkörcülük ve palamar hizmetlerine ihtiyaç duyulmaktadır. Bu hizmetler genel olarak "teknik seyir hizmetleri" (technical-nautical services) olarak isimlendirilmektedir. Teknik seyir hizmetleri kapsamında gemi ve deniz araçları için sunulan römorkörcülük hizmetlerinin verimliliği, teşkilatların işletme maliyeti ve hizmet kalitesi açısından son derece önemli bir konudur. Römorkör hizmetinin sunulma biçimi, hizmet talebini yerine getirme zamanı, hizmet sahasının büyüklüğü, çekme kuvveti yeterliliği, römorkör sayısı ve manevra kabiliyeti bu hizmetin başlıca kalite ölçütleri arasındadır.   Bu araştırma, 2011 yılında Gemport Kılavuzluk ve Römorkörcülük Hizmetleri Teşkilatında Emniyet Kültürünü Güçlendirme Çalışmaları sırasında teşkilatın ihtiyacına yönelik olarak geliştirilmiştir. Araştırma, teşkilatın Gemlik Körfezi'nde sunmuş olduğu teknik seyir hizmetleri kapsamında kullanmış olduğu iki adet römorkörün "park" yerlerinin belirlenmesi amacıyla geliştirilmiştir. Araştırmada gemi trafiği varış zamanı verileri, gemi ölçülerinin dağılımı, limanlardaki yük elleçleme zamanlarına ait veriler ve hizmetin verilme şekli konusunda yapılan görüşmelerden elde edilen bilgiler kullanılarak bir algoritma geliştirilmiştir. Bu algoritma Promodel simülasyon programında test edilerek optimum römorkör park yerleri belirlenmiştir. Römorkörcülük hizmetinin verildiği sahada belirlenen bu en uygun park yeri noktaları, römorkörlerin park yerinden hizmet verme noktasına gidiş süresi ile hizmet verdikten sonra da park yerine dönecekleri süre toplamının optimizasyonuyla sağlamıştır. Technical-nautical services such as pilotage, towage, and mooring are needed in order to ensure the safety and efficiency of ship manoeuvring at ports, In the scope of these services, efficiency of the towage service provided for the ships or maritime structures is an issue of utmost importance for the operating costs and service quality of towage organizations. The main quality criteria of towage service are the methods of towage services provided, response time of services, size of service area, pulling capacity, numbers and manoeuvrability of the tugboats.   This research was developed in 2011as a response due to the needs of the Gemport Pilotage and Towage Services Organizations, during the "Project for Enhancement of Safety Culture in Pilotage and Towage Services" in Gemlik Bay. The aim of this study is to determine the optimum parking locations for two tugboats which are being used in towage service in Gemlik Bay. The optimization of parking locations was defined as an optimization of the travel times from "parking location" to "service commencement location" and from "service completion location" to "parking location" of the tug boats for all possible parking location combinations. In order to achieve the aim of the research, the data regarding the number of ship traffic at all jetties, arrival times of ships, sizes and durations at the berth of ships were gathered from Information Management System of Gemport Pilot Organisation. Towage services algorithm was developed using data obtained from interviews with marine pilots. A simulation model was developed using statistical data and interview. Afterwards simulation model was run in the Promodel Simulation Program for all parking location combinations of tugboats. As a conclusion, optimum parking locations were selected using simulation optimization outcom

Uncertainty in maritime risk analysis: Extended case study on chemical tanker collisions

Uncertainty is inherent to risk analysis. Therefore, it is extremely important to properly address the issue of uncertainty. In the field of risk analysis for maritime transportation systems, the effect of uncertainty is rarely discussed or quantified. For this reason, this article discusses a case study dealing with risk analysis for a chemical spill in the Gulf of Finland and analyses the related uncertainties by adopting a systematic framework. Risk is assessed in terms of the expected spill frequency and spill volumes caused by collisions between ships and chemical tankers in the Gulf of Finland. This is done by applying a collision consequence with a novel approach-to-collision-speed linkage model and Gulf of Finland-specific causation factors, which are based on reanalysing accident data. This article also presents a metamodel for assessing collision probability with initial vessel speeds for any given scenario where a chemical tanker is about to be struck by another vessel. Even when conducting a risk analysis using state-of-the-art methods, there is still a medium-high degree of uncertainty in the model presented in this article, which only becomes apparent when conducting a systematic uncertainty assessment analysis. However, an uncertainty assessment is an important part of quantitative maritime risk analysis. For this purpose, a qualitative framework for uncertainty assessment analysis is introduced for general use in the field of maritime risk analysis.</p

A traffic density analysis of proposed ferry service expansion in San Francisco Bay using a maritime simulation model

A proposal has been made to the California legislature to dramatically increase the frequency and coverage of ferry service in the San Francisco Bay area. A major question in the approval process is the effect of this expansion on the level of congestion on the waterway and the effect this will have on the safety of vessels in the area. A simulation model was created to estimate the number of vessel interactions in the current system and their increases caused by three alternative expansion plans. The output of the simulation model is a geographic profile showing the frequency of vessel interactions across the study area, thus representing the level of congestion under each alternative. Comparing these geographic interaction profiles to a similar one generated for the current ferry service in the San Francisco Bay allows evaluation of the increase in exposure of ferries to adverse conditions, such as, for example, the interaction of high speed ferries in restricted visibility conditions. This analysis has been submitted to the legislature as part of the overall assessment of the proposal and will be used in the expansion decision

Anticipating the Effects of Economic Displacement in Marine Space with Agent Based Models

As marine space is managed into appropriate resource use areas, it is inevitable that some is allocated towards a mutually exclusive spatial activity. This exclusion results in displacement that has real economic consequences. When a wind energy area is placed in coastal waters, navigable space is reduced and vessels are displaced from their former routes. The USCG is concerned that re-routing will result in vessels navigating within closer proximity than they would otherwise in an open ocean scenario, and fear that this will increase the risk of vessel collision (USCG 2016). They recommend research into tools that are capable of predicting changes in vessel traffic patterns (USCG 2016). Agent based models are a method capable of predicting these traffic patterns, and are composed individual, autonomous goal directed software objects that form emergent behavior of interest. Agents are controlled by a simple behavioral rule, they must arrive at their destination without colliding with an obstacle or other vessel. They enforce this rule with the gravitational potential that exists between two objects. Attractive forces pull each agent towards their destination, while repulsive forces push them away from danger. We validated simulated vessel tracks against real turning circle test data, tested for the presence of chaotic systems, developed metrics to assess transportation costs, and applied the method to assess a wind energy area located outside of the entrance to the Port of New York and New Jersey

Traffic-conflict-based modeling of collision risk in port waters

Ph.DDOCTOR OF PHILOSOPH