bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Ryan Ramp-A Unique Stabilizing Design for a Dynamic Situation
Authors: Ryan William J. 
Published: October 2008

ABSTRACT
The Ryan Ramp (Patent pending) is a unique structural design which affords safe transfer of personnel and equipment between vessels and offshore structures.
A study conducted on the prototype ramp under actual field conditions is presented in this paper. The tests relate the forces involved in the system and the stability imparted to the vessel. The swing rope and personnel basket are also compared with this new technique. Design details are discussed.

INTRODUCTION
Problems in the transfer of personnel and equipment at sea have been in existence since the invention of boats. Although many devices have been designed to solve this problem, the offshore industries generally use two basic methods: the personnel basket and the swing rope. These techniques have managed to keep the industry operating, but not without problems.
The purpose of the Ryan Ramp is to increase safety and accessibility to offshore structures. This new design has been in active use for over a year and was used in all operational sea conditions without a malfunction. It weathered Hurricane Carmen, which had 180 mile per hour winds, without damage to the platform or the ramp.

DISCUSSIONS

Swing Rope
The swing rope is the least expensive and the most used method. It operates satisfactorily in light seas with no outside assistance. However, many accidents have resulted from this technique. A person using the swing rope successfully must possess the following physical dexterity:Confidence in his ability to negotiate the transfer.Timing in order to grab the rope when the boat is on the top of the swell.Judgment as to when to release from the rope. Otherwise, he may swing back between the boat and the structure.Strength to hold his body weight by his hands alone while swinging.Agility to adjust to the impact when he hits the deck while maintaining balance on a moving boat.
In using the swing rope, the boat operator must position the boat close to the structure and the man preparing to use the swing rope must get close to the side or stern of the boat. If a swell surges the vessel into the platform, the impact can cause damage and send him over the side.

Personnel Basket
The personnel basket requires a crane on the structure which has as its primary function: the handling of heavy equipment. It is relatively inexpensive and is more effective in rougher seas than the swing rope.
This method requires the structure be manned in order to operate the crane. It is limited by the skill and ability of the crane and boat operators, as well as the ability of the passengers on the basket. Also, the loose construction of the basket tends to give the passenger a feeling of insecurity, particularly when he is hanging on the outside high above the water. Since the crane operator is located well above the boat deck, many accidents have resulted from misjudgments.
An Advanced Two Axis Acoustic Current Meter
Authors: Hardies Charles E. 
Published: October 2008

ABSTRACT
A Current Meter for long "in situ" performance in the ocean environment is described. The problems solved in applying acoustic techniques to current measurements in open flow channels, the limitations of these techniques, and test results are presented. The meter has good accuracy, it has no moving parts, and it consumes very little power. Its short and long term stability are both excellent. These features together result in an instrument uniquely suited for long unattended use in the ocean environment.

1 INTRODUCTION
The Oceanic Division of Westinghouse is a manufacturer of acoustic flowmeters. (1, 2) We also supplied the sensor system for the engineering experimental phase of the National Data Buoy Development Project. (3, 4) As a continuation of these programs, we have a development program on a new acoustic current meter. The purpose is to provide users with a reasonably accurate and reliable meter that is capable of long "in situ" operation. (5) We are using an extension of the principle used on our Westinghouse flowmeter, namely the difference between acoustic pulse travel times in opposite directions thru the same path. Flowmeters using this basic principle have been field proven to be both accurate and reliable. Systems are presently achieving approximately 0.1% accuracy.
Our interest in current meters resulted from the difficulty we experienced with the water current sensors on the Engineering Experimental Phase of the National Data Buoy (NDB) program. As sensor system supplier, we had to identify sensors for the various measurands. We were able to identify sensors that offered a high probability of successful performance over the target one year deployment for all of the parameters except current. (4) The requirement for long deployments eliminated current meters with moving parts. Figure 1 shows one of the oceanographic sensors after 6 months dep10yment.which has been antifoulant coated with tetratributyl tin oxide prior to its deployment. The two types of meters that we concluded could function for a year, and had reasonable accuracy and power consumption were the electromagnetic and the doppler acoustic types. The problem with the electromagnetic sensor is that its response to currents other than in line with the probes is nonlinear. Cosine response is required for a sensor in order to output the two orthogonal components of the current. We saw no way to improve the EM meter and chose to use the acoustic doppler. Several of these sensors were procured and tested. We found them unacceptable in water where the concentration of particles for the sound to backscatter from was low. This problem was encountered in tests at the David Taylor Model Basin tow tank, and later in at-sea tests in the Gulf of Mexico.
The Westinghouse flowmeter is specifically designed to measure volumetric flow in closed conduits such as pipes or rivers. It was included in the evaluation of transducers for the oceanographic sensors, but the development effort required to change it to a current sensor was not compatible with the NOB program schedule.
Display Parameters of Marine Geophysical Data
Authors: Sheriff R.E. , Farrell Judy E. 
Published: October 2008

ABSTRACT
The display of marine geophysical data has an important influence on the ability of an interpreter to recognize and understand interrelationships among data elements. For seismic record sections, the proper choice of such parameters as horizontal and vertical scales, the number of traces per horizontal unit, the trace amplitude color, and black/white bias may aid the interpreter in his search for significant structural and stratigraphic features.
Continuity of events can be emphasized with variable area displays. Superimposing a wiggle plot on the variable area aids the interpreter in detailed work. Vertical exaggeration also emphasizes reflection alignment but loses some details of wave shape.
Apparent information content is altered by varying display parameters. The choice of these parameters, therefore, has a critical effect on the ability of the display to communicate information to the interpreter.

INTRODUCTION
The volume of geophysical data which an interpreter must comprehend and interrelate is vast. The output of a marine seismic crew can be in the order of 100 reels of magnetic tape per day. The interpreter must be able to search through these data for significant features for mapping of earth structure. He must attempt to determine the nature of the rocks and the fluids which they contain and he must be able to interrelate data elements to check the internal consistency of his interpretation hypotheses. If oil is found in the minds of men, as it is often said, then the problem we have to face is how to get our geophysical information into the mind of the interpreter in a form that he can comprehend.
Marine seismic data are usually acquired along lines of traverse and displayed in record section form. The abscissa of a seismic record section is location along the seismic line and the ordinant is the travel time of reflections. The travel time, in a crude way, indicates the depth of the reflectors (when allowing for velocity and reflector dip) so that the seismic section is sort of a pseudocross-section of the earth indicating reflecting interfaces.

DISPLAY MODES
Seismic data are ordinarily displayed in wiggle, variable area or variable density form, or a superposition of these forms. Display parameters include choice of horizontal and vertical scale, the number of traces per horizontal unit, the trace amplitude, the degree of overlap between adjacent traces, and the zero-line bias.
The term "wiggle" describes the appearance of the individual trace on the record section, where displacement from a zero line indicates data values. It is simply a conventional graph display. This display is generated by pen plotters, raster-scan plotters and analog plotters commonly in use today. One significant quality of this display mode is that it allows the interpreter to see details of waveshape.
New York Bight- An Environmental Baseline Study
Authors: Cox Geraldine V. , Wastler T.A 
Published: October 2008

1.0 Abstract
This paper summarizes the field data collection effort associated with the first comprehensive baseline survey of a proposed ocean disposal site under the Marine Protection and Sanctuaries Act of 1972, PL 92–532.
This study included data collection of every environmental element associated with the proposed ocean disposal site. It resulted in 45,000 discrete data points relating to over 2,000 species and approximately 45 different types of environmental measurements. Three cruises were conducted within a one-year period, and the data collection effort was as synoptic as logistics would allow.
The results of the study are used to characterize conditions prior to sludge disposal as well as to form a data base against which a monitoring program will be developed. Accurate baseline documentation is essential to generation of a statistically-based monitoring program capable of defining environmental changes which result from sewage sludge disposal at the site.

2.0 Background
Barged Ocean disposal of waste materials was first regulated under the 1888 Rivers and Harbor Act. Under this act, areas for the disposal of mud, cellar dirt, stone and wrecks were established in areas where they would not be considered hazardous to navigation. A site for the disposal of sewage sludge was selected in 1924, and it has been in continuous use since that time. The acid waste site was established in 1948 and has been used since that time. Figure 1 illustrates the dispersal pattern of acid wastes in the New York Bight Apex.
In 1965 a toxic wastes site was established about 120 miles southeast of New York.. The locations of these sites and a use summary are presented in Table 1. Roughly 27% of all wastes discharged in this period from 1960–1974 were sewage sludge solids.
In 1974, for example, 3.7 × 10 6m3 of sludge (4.9 × l06yd3) were released at the New York Bight sewage sludge disposal site.
Since 1971, considerable concern about sewage sludge movement and impact has encouraged many studies in the New York Bight apex. Most of these studies were conducted under the auspices of the MESA program of NOM. Charnell3 reviews these data; and MESA4 released a recent review. Cox5 presents a summary of ocean disposal in the United States.
Public pressure against sewage sludge release 12 miles from area branches caused the Environmental Protection Agency to seek an alternative sewage sludge disposal site. They asked NOAA to designate candidate sites, and the study site, Figure 2, was one of the two NOAA nominations. EPA issued contract 68-01-2770 to Raytheon Oceanographic & Environmental. Services to perform the first comprehensive environmental baseline study conducted under PL 92–532, The Marine Protection and Sanctuaries Act of 1972.
On-Bottom Pipe line Stability In Steady Water Currents
Authors: Jones Warren T. 
Published: October 2008

ABSTRACT
A recommended practical is established for the on-bottom stability design of a pipeline subjected to steady water currents. The analysis leading to the recommended design procedure recognizes that, the water velocity decreases as the bottom is approached due to the boundary layer effect and that the magnitude of the hydrodynamic forces on the pipe will be a function of the shape of this velocity profile. The analysis also assumes that the lateral resistance to movement provided by the bottom soil is proportional to the net vertical resultant force acting on the bottom. Equilibrium, or stability, occurs when the lateral resistance is just equal to the forces exerted on the pipeline by the steady current. The resulting design equation (or the required pipeline weight contains several parameters whose numerical value depends on the pipe, seawater, and soil properties. A nominal see of these values is chosen and a parametric study is made of their effect on the required pipeline weight. Design curves are generated based on the chosen parameter values, and procedures for their user are recommended. The parametric study demonstrates that the minimum specific gravity required for equilibrium is relatively insensitive to large variations in the value of most of the parameters in the design equation. It also demonstrates that the selection of the design current velocity is the most significant factor in the stability analysis. Hence, further research on stability can most profitably be aimed at developing better methods of determining the design velocity for a particular location in the ocean.

INTRODUCTION
The design of an offshore pipeline system must give due consideration to each of the following factors. The operating requirements internal pressure, throughput, etc. have a large influence on the design. At the same time the design must provide for the safety and integrity of the line in the face of external and environmental factors over the expected lifetime of the system. Factors influencing the selection, design, and efficiency of the construction system must also be included in the overall consideration of the design.
The specifications for the line pipe and the pipe coating system must not exceed those required to ensure adequate operating performance and long-term safety of the line. Unnecessary pipe weight and too stringent pipe handling criteria impose undue operating limits on present construction systems even in moderate water depths. In deeper water they may impose impractical requirements on the construction system. The selection of the pipe and specifications for the coating system are directly affected by the criteria established for the maximum environmental conditions expected over the life of the pipeline. Therefore, the environment of the operating pipeline is the basic starting point for the design.
A complete discussion of the environment near the seawater soil interface is beyond the scope of this paper.
Evaluation of Fatigue Considerations in the Design of Framed Offshore Structures
Authors: Kallaby Joseph , Price James B. 
Published: October 2008

ABSTRACT
Fatigue is an important consideration for deep water platforms in hostile environments such as the North Sea and the Tasman Sea. This paper evaluates the implications of the fatigue criteria on platform design using recent experiences with the Maui Platform A offshore New Zealand. It underlines the importance of realistic fatigue criteria and examines various methods for analysis. The need for estimating appropriate stress concentration factors is illustrated. The impact of fatigue on the weight and cost of the platform is discussed.

INTRODUCTION
Offshore structures installed in the hostile North Sea can be subjected to fatigue loading far exceeding that experienced in the Gulf of Mexico. The China Sea and offshore Australia and New Zealand are examples of other areas imposing a fatigue premium. Several papers have dealt with various elements of the analysis and design for fatigue with attention focused on estimating the stress concentration factors at the nodes of frame structures.
This paper evaluates the significant elements of fatigue design using recent experiences with the Maui Platform A, installed offshore New Zealand. It evaluates the importance of realistic fatigue criteria and examines various methods for analysis. A comparison of stress concentration factors determined with several proposed equations and a finite element analysis is presented. The weight and cost implications are discussed.

MAUl PLATFORM A
The Maui Platform A, Fig. 1, presently being installed in 354 feet of water some 23 miles offshore Taranaki, North Island, New Zealand, consists of a 432 foot tower topped by three deck levels for development drilling, production and processing of 660 MMscfd of gas and 20,000 bpd of condensate through 12 wells.
The four legged tower is 70x 160 feet at the top and 160 × 160 feet at the base with the broad sides battered and the narrow sides vertical (Fig. 2). Two of the legs are 22 feet in diameter necking down to 6 ft. at the top. The legs served as pontoons to float the tower on a 5200 mile journey from the fabrication site in Japan to New Zealand. The other two legs are 6 feet in diameter increasing to 16 feet in the bottom panel. The tower is anchored to the seabed with twenty-eight 48 inch diameter steel piles driven to 240 feet penetration.
The tower float out weight is 14020 kips. Maximum deck loading is 24000 kips. The mass for calculations of the dynamic properties of the platform is 100,000 kips, which includes added mass. Steel specifications called for normal DIN steel with 50 ksi yield strength. To enhance the resistance of the structure to fatigue, improved DIN steel, with special impact and through-thickness properties, was specified at the joints. Approximately 2500 kips of this special steel was required. Further discussions of the tower is given in Ref. 1 and 2.
A Deep-Tow Multi-Purpose Sparker System
Authors: Harrington Patrick K. , Moody C. Douglas 
Published: October 2008

ABSTRACT
Sea trials were conducted on deep tow Sparker profiling equipment. Preliminary results indicate that data can be obtained of higher quality and in significantly worse sea conditions compared with equivalent surface towed systems. The addition of a tape recording facility should partly eliminate the problem of combining high resolution with good penetration. Cost will be comparable to existing surface towed systems, with mobility and operational flexibility only slightly reduced.

1. INTRODUCTION
For many years, engineering seismic profiling surveys have been conducted under a number of limitations. Foremost amongst these is the problem of obtaining consistently good records in sea conditions resulting from wind forces greater than about force 3. In the North Sea this problem has become progressively more important as oil activity has flowed northwards into rougher, more exposed waters. At the latitude of the Shetlands in winter, successful profiling work is normally restricted to a very few short lulls of seldom more than a few hours duration and, as often as not, at times when accurate navigational systems cannot be used. Ship's propeller noise can be an allied problem. This varies markedly from ship to ship, is difficult to predict and requires skill and experience to eliminate. Some vessels are virtually unusable. A third problem is that increasing resolution tends towards decreasing penetration. Inevitably same compromise is necessary between the power and the frequency of the seismic source.
With such limitations in mind targets were set to increase the usefulness of the profiling system. These targets are:-SEA NOISETo obtain good quality records in sea states corresponding to winds up to at least force 6.ENGINE NOISETo be able to use any vessel without interference from engine noise.PENETRATION AND RESOLUTIONTo be able to obtain records combining good penetration with high resolution from a single system. (Specifically 300 feet of penetration through sediment, with an ability to resolve down to 1 foot in the uppermost 30 feet).COSTCosts should not differ markedly from conventional surface towed equipment.PORTABILITYThe system should be fully portable and capable of operating from boats down to about 30 feet in length.
Targets 1 and 2 (sea and engine noise) can be overcome by the use of deep-tow equipment. However to satisfy 4 and 5 (cost and portability) it was necessary to use existing equipment wherever possible. Target 3 (penetration and resolution) is more difficult. A Multielectrode Sparker has the necessary frequency content and power handling capability, but like all other sources cannot normally achieve both aspects of the target on a single-pass. A partial way round this is to tape input. To keep within the cost target an analogue or very simple digital system is required and, it must be confessed here, this target has not yet been satisfactorily achieved.
An Advanced Sonar for Hydrographic Survey
Authors: Colvin Douglas W. 
Published: October 2008

ABSTRACT
Admiralty charts published by Hydrographer, Royal Navy, are used world-wide, but many relating to British coastal waters have not been up-dated since the last century. The United Kingdom is surrounded by some of the busiest shipping routes in the world. Many vessels are of a draught undreamed of 20 years ago. Offshore exploration and exploitation is taking place throughout the Continental Shelf at an accelerated pace. To keep up with these developments, the marine surveyor is now required to work faster, more accurately, and to greater depths, over very large areas of the seabed. The present paper summarizes the evidence available on the inadequacy of hydrographic charts, describes detailed field trials of research sonar equipment, presents parameters and design criteria for new survey equipment, describes pre-production equipment now under manufacture and summarizes its proposed method of deployment in the field.

INTRODUCTION
The Hydrographer of the Royal Navy runs an organization responsible for carrying out depth soundings and producing Admiralty Charts used by mariners world-wide. For some years now he has inserted cautions in the Mariners' Handbook (1) and issued regular Notices to Mariners (2) drawing attention to the dangers involved in reading false security into his charts.
It is necessary to look more closely at the background to the general concern and at what has led Hydrographer to issue such serious warnings about the inadequacy of his own products.

SHIPPING STATISTICS.
We begin by looking at trends in accident statistics, the increase in world shipping, its change of character and the causes of accidents.
Annual total loss figures have risen fairly steadily for many years (3): from just under 3 × 105 ft (87 ships) in 1958 to record levels over 1 × 106 gt in 1972-74 (195 ships in 1974). Tanker losses were 7 (8%) in 1968 and 25 (13%) in 1974. This latter figure, however, constituted more than 20% of all total losses (the 1972 figure was 44%). In this time the world fleet tonnage had risen by a factor of 3 to more than 3 × 108 gt and its composition changed. In 1958 VLCCs constituted 1/3 of the world fleet. By 1973 they accounted for almost 3/5 (4), oil tankers alone equating to the total world fleet in 1958, and representing, as a single category, almost 40% of the 1973 world fleet. 1973 was an outstanding year for world ship building, but the world order book itself rose to the phenomenal total of 1.3 × 108 tons at the end of December. The world tanker order book constituted 75% of this, almost equaling the then world tanker fleet. A year later the world economic crisis had begun to take effect and the decrease in world trade, especially in oil, reduced demand.