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Collaborating Authors
Regional Government
ABSTRACT There is much room for improvement in the use of techniques involving risk assessment and technical analysis in the public policy decision making process as it applies to the marine field. The example of the regulation of tanker design, as mandated in the Oil Pollution Act of 1990, is utilized as a case study. Proper risk assessment for the complex ~waterway system requires a total-system approach, which is currently beyond the state-of-the art, but the public demands an immediate response to what it perceives as a straight-forward problem and government must react. This paper discusses the further work needed in the areas of methodology, data bases, and communication/education to properly address these policy decisions. INTRODUCTION. While techniques involving risk assessment and technical analysis are well respected and used in industry and ~ a, there often seen~ to be a dearth of such methodologies in the public policy decision making process as it applies to the marine field. This paper will. use the example of the regulation of tanker design, as mandated in the Oil Pollution Act of 1990 (OPA 90), as a case study. The tanker/waterway system is large and complex (and oil spills are a dynamic random-product). A valid "assessment of risk for such a system cannot be made by analyzing a subset of the problem or by drawing conclusions from long-term oil spill statistics. Valid risk assessmentand decision making requires a total-system model and analysis. When acc/dents occur, the public demands action, but the necessary tools to develop cost-effective solutions and to communicate the need and rationale for this process to the public do not exist. Often the solution in one scenario may not be the most cost-effective solution over all possible scenarios and vice versa.
- Law > Statutes (0.95)
- Energy > Power Industry (0.94)
- Energy > Oil & Gas (0.93)
- Government > Regional Government > North America Government > United States Government (0.69)
ABSTRACT: Mariners transiting the 70+ mile waterway complex bounded by the ports of Houston, Galveston, and Texas City are routinely affected by high winds, strong currents, low water levels, and sporadic shoaling. These conditions challenge the mariner's ability to control ships and Imrge-pushin8 towboats. Narrow, dredged channels provide the only means of transiting the area and do not offer abundant room to avoid other vessels. The combination of these and other factors led to a total of 1,525 groundings from 1986 through 1995 as documented by the U.S. Coast Guard Vessel Traffic Service (VTS) monitoring region. VTS loosely defines groundings for their statistical records as an interaction with the bottom which leads to the inability of the master to refloat the vessel at will. Wind, current, and low tide were given as the primary muses in 481 groundings equating to 31.6 percent of the 1986- 1995 total of 1525 groundings. Very recent statistical data indicates a eleven year total (1986–1996) of 1,644 groundings in Galveston Bay. For the ten year period (1987–1996) of pro-active HOGANSAC-USCG waterways management of aids to navigation, there were 1,335 Galveston Bay groundings. The 1987–1991 total groundings were 932. The 1992–1996 total groundings were 403 wich reflects a 57% reduction between the five year periods of management Today, mariners are benefiting from the installation of a modern technological system. Since late-1995, National Oceanic and Atmospheric Administration (NOAA) personnel, members of academia, the maritime community, and the Coast Guard have acted in concert to acquire, deploy, and disseminate~ critical real~ weather, current, and tidal information from a Physical Oceanographic Real-Time System (PORTS). This intelligence can provide every mariner with advance data regarding waterway and meteorological conditions that will affect their vessels.
- Transportation > Marine (1.00)
- Government > Regional Government > North America Government > United States Government (1.00)
- Government > Military (1.00)
ABSTRACT The culture, design, and operation of the maritime industry all contribute to create an error-inducing system. While risk acceptance and risky behavior are often attributed to the "traditions of the sea," the risks associated with sea transportation are no longer restricted to the domain of the seafarer. As oil tankers have gotten larger, the tolerance for error has decreased, and the consequences have increasecL While the tanker industry has been identified by the USCG has a high-risk industry, the USCG has also stated that the industry has a high potential for improvement. A systematic approach must be undertaken to effectively identify tanker accident risks and consequences so that they can be minimized by appropriate safety measures. This paper concentrates on one aspect of a Level 1 Probabilistic Risk Analysis (PRA) for tanker groundings. The approach utilizes fault trees and event trees and incorporates The Human Error Rate Prediction (THERP) data to quantify individual errors. The Motivation Maritime oil spills are a significant international environmental problem. The culture, design, and operation of the maritime industry all contribute to create an error-inducing system (Perrow, 1984). Of. ten, the consequence of these errors is the release of oil into the world's waterways. Since off spills are low probability-high consequence events, and difficult to predict, prevention is the best response It is the risk of an oil spill that motivates further investigation.
- Transportation > Marine (1.00)
- Government > Regional Government > North America Government > United States Government (1.00)
- Energy > Oil & Gas (1.00)
- Transportation > Freight & Logistics Services > Shipping > Tanker (0.89)
Toward a Port-Level Model of the Physical Risk of Grounding
Kite-Powell, Hauke L. (Woods Hole Oceanographic Institution) | Jin, Di (Woods Hole Oceanographic Institution) | Giziaki, Ernestini (University of Athens ) | Jebsen, Johan (Massachusetts Institute of Technology) | Papakonstantinou, Vassilis (Massachusetts Institute of Technology) | Patrikalakis, Nicholas (Massachusetts Institute of Technology)
ABSTRACT We formulate a Bayesian model to estimate the physical risk of groundings during transits into and out of port as a function of explanatory factors. We assemble and analyze information on factors surrounding groundings in five U.S. ports between 1981 and 1995. Although the data are far from perfect, it is possible to establish associations between grounding risk and changes in factors such as vessel type and size, wind ~ and visibility. We apply the model to an investigation of the effect of visibility on the risk of grounding in the Port of New York/New Jersey. 1. INTRODUCTION A collaborative research project on Formulation of a Model for Ship Transit Risk was started in late 1995 by researchers at the Massachusetts Institute of Technology's Ocean Engineering Department and the Marine Policy Center of the Woods Hole Oceanographic Institution. The project was developed as a three-year research activity. The focus of the first year was on collection and assimilation of data to support an improved understanding of factors that contribute to vessel groundings. Groundings of commercial ships account for about one third of all commercial maritime accidents, including some of the most expensive in the United States" history, such as the Exxon Valdez. Many factors contribute to vessel groundings. Some of these factors are of particular concern to federal agencies responsible for aspects of the nation's marine transit routes. For example, the National Oceanic and Atmospheric AdminisU~tion (NOAA) is responsible for the stwvey of U.S. waters and for the publication of nautical charts. The U.S. Coast Guard (USCG) and the U.S. Army Corps of Engineers (ACE) are responsible for navigation aids and for channel design and maintenance, respectively. All of these aspects may influence how likely groundings are to occur.
- Government > Regional Government > North America Government > United States Government (1.00)
- Government > Military (1.00)
- Information Technology > Information Management (0.67)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Uncertainty > Bayesian Inference (0.34)
- Information Technology > Artificial Intelligence > Machine Learning > Learning Graphical Models > Directed Networks > Bayesian Learning (0.34)
ABSTRACT A unique field test was conducted in July 1995 to check the load-deflection characteristics of the breasting dolphins of Ras Tanura Sea Island No. 2, The purpose of the test was to confirm the assumptions used in the mathematical simulation and structural analysis of the dolphins. A secondary objective was to check whether there is a "play" in the structures, i.e. whether the dolphins deflected one way or the other under no significant load. Two opposing dolphins of different berths were tested simultaneously. Deflections measured were in line with the expected deflections predicted by the computer structural simulation. The facility, test apparatus and procedure are described in this paper. Results of measured deflections and the corresponding computer simulation plots are also presented. INTRODUCTION Ras Tanura Sea Island 2 is a crude oil loading terminal which was constructed in 1969. The breasting dolphin structures consist of steel decks, supported by but rigidly connected to, free standing vertical piles. The water depth at the Sea Island is about 90 feet. It has been reported that large lateral deflections have been observed in relatively calm weather. The conditions have been reported to have deteriorated over the years and caused some concerns about the integrity of the structures. Therefore, it was the objective of the static field load test on the existing Outer Breasting Dolphin (OBD) structures at Sea Island 2 to measure:Load/Deflection characteristics of OBD=7 of Berth=15 and OBD=8 of Berth-16 structures under lateral loads. This is to compare the results with the computer simulation and come to a conclusion regarding the relationship between the ~test results and computer modeling. "Play" of the OBD structures, i.e. the deflections associated with small lateral load application. The "Play" measurements are to verify the structural behavior in opposite directions under small load.
- Energy > Oil & Gas (1.00)
- Government > Regional Government > Asia Government > Middle East Government > Saudi Arabia Government (0.97)
ABSTRACT This paper investigates determinants of the total loss risk of ship (tanker, container and bulk)accidents. The results suggest that loss risk is greater for smaller than for larger sized ships and for human-caused and fire/explosion ship accidents than for other accidents. Also, it is greater when the weather is foggy, at higher wind speeds and in an ocean or gulf waterway, but less if the ship is manned by a licensed operator. The incremental loss risk (among binary variables) is greatest for a fire/explosion accident. I. Introduction In 1980, the number of ship accidents for which the ships were a total loss was 387, representing 1.8 million ship gross tons; by 1990 these figures had declined to 188 losses and 1.1 million gross tons (Lloyd's Register, 1991). Although these data suggest that the safety of ocean transport has improved, safety concerns remain. Among marine insurers there is concern that the inspection of ships by classification societies has failed to spot defects and that maintenance of much of the world's aging ship fleet needs to be improved. Also, competition among open registries - the registration of ships by owners in foreign countries - has the potential to lower ship safety standards. Do ships classified by a particular society or having a certain flag of registry have a greater risk of total loss in an accident? Does the age of a ship or the cause of its accident (e.g., human, environmental or ship) increase this risk? The purpose of this paper is to investigate the effects of these and other factors on the total loss risk of a ship accident, i.e., on the (conditional) probability that a ship accident (having occurred) will result in the total loss of the ship.
- Transportation > Marine (1.00)
- Law (1.00)
- Shipbuilding (0.95)
- (2 more...)
ABSTRACT Economic and environmental pressures have required the Navy to minimize dredging when determining the depth of entrance channels for deep draft ships. To maintain the capability of these deep draft ships transiting shallow entrance channels safely, the Navy has developed a risk-based methodology to aid in grounding avoidance and minimizing required channel depth. This methodology generates a prediction of the underkeel clearance of the ship during transit of a channel of a defined depth and calculates the associated risk. The risk of the ship touching the channel bottom is calculated based upon the uncertainties in each of the major parameters contributing to the underkeel clearance prediction. A summary of the details of the underkeel clearance prediction, the risk model, and its application in an operational system and channel depth determination is provided. INTRODUCTION Some of the U.S. Navy's large deep draft ships have home ports in harbors that have entrance channels that are both shallow and exposed to waves. Economic and environmental pressures have required minimizing the amount of dredging of the channels. This has resulted in less than fully accessible channels for these ships. To respond to these constraints, the Navy has developed an operational system, known as the Environmental Monitoring and Operator Guidance System (EMOGS), to predict the net effective clearance between the keel of the deep draft Navy vessels and the channel bottom before they transit the shallow entrance channel. A risk analysis has been developed for the system and applied to aid in assessing the amount of risk of grounding for the calculated underkeel clearance. Additionally, the methodology has been used to determine the optimum channel depth for a deep draft ship. The optimum channel depth is defined as the depth which allows the maximum accessibility with the least amount of dredging.
- Government > Regional Government > North America Government > United States Government (1.00)
- Government > Military > Navy (1.00)
ABSTRACT This paper presents the results of the technological assessment of steel pipe pile cutting technologies, and the preliminary tests of an automated plasma arc cutter. A rapid pipe cutting technology is needed in support of the Navy Modular Elevated Causeway System, which transfers cargo from ships moored offshore to an unimproved beach staging area. The developed cutter will be used to improve the efficiency of the causeway system installation by reducing the pile cutting time from 20 minutes with the current practice to less than 3 minutes. INTRODUCTION The U.S. Navy is developing a rapid pipe steel pile cutting technology to improve the installation of the Navy Modular Elevated Causeway System (ELCAS(M)). The elevated causeway system is used to transfer logistics cargo from ships moored offshore to any unimproved beach staging area during an amphibious operation. The causeway system consists of a ramp, roadway, pierhead, and driven pile foundations. A part of the elevated causeway during construction is shown in Fig. 1. The modules of causeway sections, construction equipment, and supporting vehicles are unloaded from ships, ferried to the beach staging area, and assembled. The installation of the modular causeway sections begins from the beach toward the ocean by a cantilevering process. The installation sequence is from ramp, roadway, to pierhead. The causeway sections are elevated to 6 meters above the water surface at high tide to eliminate any environmental interference from waves, the tide, or current during installation and operation. The causeway system adopted the modular concept that each structural module is prefabricated to a standard dimension. The modules require minimal preparation or modification in the field. The modules and their parts are interchangeable to keep the inventory simple. The entire causeway system is supported by driven piles.
- Materials > Metals & Mining > Steel (0.90)
- Government > Military > Navy (0.68)
- Government > Regional Government > North America Government > United States Government (0.34)
ABSTRACT The Naval Facilities Engineering Service Center (NFESC) was tasked to develop a conceptual design package for an expeditionary port facility capable of rapid installation, simultaneous offload of two deep draft cargo ships during operations, and located up to 3 km offshore. The system design for the Rapidly Deployed Pier (RDP) includes a floating multi-deck pierhead moored by a single point mooring at the bow and a compliant mooring system aft, allowing the pierhead to be rotated about the SPM pivot point. The floating pierhead is connected to shore by a fixed, elevated approachway constructed using a cantilevered construction method. INTRODUCTION In October 1995, the Defense Advanced Research Projects Agency (DARPA) tasked the Naval Facilities Engineering Service Center (NFESC) to develop a system concept and design package for an expeditionary port facility capable of offloading deep draft cargo ships across unimproved shorelines. The work was led by NFESC, with contracted support provided by M. Rosenblatt & Son, Inc. in association with Elliott Bay Design Group, IMODCO, Inc., MAR, Inc., MCA Engineers, Inc., The Logistics Management Institute, Chesapeake Marine Design, Inc., and USA Models. This paper presents the results of the design and development effort. SYSTEM MISSION The mission of the RDP is to expeditiously provide port facilities for deep draft cargo ships in areas where adequate port facilities do not exist or have been damaged. Current methods for providing logistics support over unimproved shorelines require in-stream offload of ships to lighters, which transport the cargo either directly to the beach or to a shallow water expeditionary pier facility. While these methods are adequate for delivering relatively small quantities of cargo, they are not suitable for larger scale operations that require frequent offloading of modem containerships, Roll-On/Roll-Off (RO/RO) ships, and other deep draft ships bringing cargo to the operating area.
- Transportation > Marine (1.00)
- Transportation > Freight & Logistics Services > Shipping (1.00)
- Government > Regional Government > North America Government > United States Government (0.68)
ABSTRACT The Naval Facilities Engineering Service Center (NFESC) is developing a logistics management system to support the shifting operational paradigm of the Unites States Navy. The shift from shore-based to sea-based facilities will require a more efficient use of operating space and will not allow for the storage of an oversupply of goods. NFESC is using Radio Frequency Identification technologies to develop a refined asset tracking system that will allow the Navy to keep a much more accurate accounting of its inventory status. Users at all points in the supply chain will have the capability to access autonomous, real-time container manifest, and asset location information as items are sent from warehousing facilities in the continental United States to off shore bases throughout the world. INTRODUCTION The Naval Facilities Engineering Service Center is tasked to study the logistical issues involved in shifting the United States Navy (USN) and Marine Corps (USMC) away from operations and exercises in foreign territories that require a large land dependency. One issue being addressed is the accurate tracking of supplies so that operating forces are neither overwhelmed or left short-handed. During the chaos of a military conflict, the movement of supplies is far too rapid to keep accurate records using manual methods. NFESC proposed to address this problem using an automated asset tracking system based on radio frequency identification (RFID) technology. Initial efforts were begun under a project entitled Recording and Tracking Technologies (RTT) sponsored by the United States Marine Corps. Using the RTT system as a baseline, a more refined system is being developed to adapt to U.S. Navy specific requirements under a project entitled Navy Total Asset Visibility (NTAV) sponsored by the Office of Naval Research. This paper presents the results of new NTAV system development and test results of RTT equipment tests.
- Government > Regional Government > North America Government > United States Government (1.00)
- Government > Military (1.00)
- Information Technology > Communications > Networks (0.67)
- Information Technology > Architecture (0.55)