scholarly journals A Case Study of Floating Offshore Super-Long Steel Pipeline Combing with Field Monitoring

2021 ◽  
Vol 11 (21) ◽  
pp. 10186
Author(s):  
Jin Yu ◽  
Chonghong Ren ◽  
Yanyan Cai ◽  
Jian Chen ◽  
Yuanqing Wang ◽  
...  
Keyword(s):  
Raw Water ◽  
Long Distance ◽  
Monitoring Method ◽  
Steel Pipeline ◽  
Timely Feedback ◽  
Feedback Monitoring ◽  
Pipeline Project ◽  
Water Pipeline ◽  
Communication Equipment

How to control deformation and avoid resonance is the key to ensuring the safety of the super-long pipeline when it is floating in the sea. Based on the deformation warning value of pipeline prototype composite material obtained from laboratory tests, the raw water pipeline project in Tong’an Xiamen adopts wireless communication equipment to transmit data, supplemented by aerial photography technology to monitor and feedback the strain and vibration during the dynamic construction of long-distance pipeline floating transportation. Combined with dynamic construction, this monitoring method avoids excessive deformation and resonance of the steel pipeline during floating transportation, and prevents the destruction of the anticorrosive coating. The airtightness test after completion shows that the whole pipeline meets the acceptance requirements. The monitoring results show that the strain at the bent position of the pipeline is large in the process of floating transportation, and the jacking speed and position of the tugboats have an important influence on the deformation of the pipeline. The same type of project should focus on these aspects and timely feedback monitoring data. At the same time, the study also provides detailed strain, modal analysis and effective monitoring technology for the safety of offshore steel pipeline floating transportation.

Effects of soil properties on corrosion of buried steel pipeline: A case study of rand water pipeline, South Africa

AFRICON 2015 ◽  
2015 ◽  
Author(s):  
T. H. Shabangu ◽  
A. A. Ponnle ◽  
K. B. Adedeji ◽  
B. T. Abe ◽  
P. A. Olubambi ◽  
...  
Keyword(s):  
South Africa ◽  
Soil Properties ◽  
Steel Pipeline ◽  
Water Pipeline

COMBINING ORAL TRADITIONS AND BAYESIAN CHRONOLOGICAL MODELING TO UNDERSTAND VILLAGE DEVELOPMENT IN THE GULF OF PAPUA (PAPUA NEW GUINEA)

Radiocarbon ◽  
2021 ◽  
pp. 1-21
Author(s):  
Chris Urwin ◽  
Quan Hua ◽  
Henry Arifeae
Keyword(s):  
Papua New Guinea ◽  
New Guinea ◽  
Oral Traditions ◽  
Long Distance ◽  
Spatial History ◽  
The Past ◽  
History Of ◽  
Gulf Of Papua ◽  
The Village

ABSTRACT When European colonists arrived in the late 19th century, large villages dotted the coastline of the Gulf of Papua (southern Papua New Guinea). These central places sustained long-distance exchange and decade-spanning ceremonial cycles. Besides ethnohistoric records, little is known of the villages’ antiquity, spatiality, or development. Here we combine oral traditional and 14C chronological evidence to investigate the spatial history of two ancestral village sites in Orokolo Bay: Popo and Mirimua Mapoe. A Bayesian model composed of 35 14C assays from seven excavations, alongside the oral traditional accounts, demonstrates that people lived at Popo from 765–575 cal BP until 220–40 cal BP, at which time they moved southwards to Mirimua Mapoe. The village of Popo spanned ca. 34 ha and was composed of various estates, each occupied by a different tribe. Through time, the inhabitants of Popo transformed (e.g., expanded, contracted, and shifted) the village to manage social and ceremonial priorities, long-distance exchange opportunities and changing marine environments. Ours is a crucial case study of how oral traditional ways of understanding the past interrelate with the information generated by Bayesian 14C analyses. We conclude by reflecting on the limitations, strengths, and uncertainties inherent to these forms of chronological knowledge.

Construction material supply risk management using Asian option contracts: the case of a pipeline project

2020 ◽  
Vol 27 (10) ◽  
pp. 3395-3414
Author(s):  
Mohammad Vahdatmanesh ◽  
Afshin Firouzi
Keyword(s):  
Risk Management ◽  
Scenario Analysis ◽  
Price Risk ◽  
Asian Option ◽  
Steel Pipeline ◽  
Content Type ◽  
Price Fluctuations ◽  
Option Contracts ◽  
Pipeline Project ◽  
Total Price

PurposeSteel price uncertainty exposes pipeline projects that are inherently capital intensive to the risk of cost overruns. The current study proposes a hedging methodology for tackling steel pipeline price risk by deploying Asian option contracts that address the shortcomings of current risk mitigation strategies.Design/methodology/approachA stepwise methodology is introduced, which uses a closed-form formula as an Asian option valuation method for calculating this total expenditure. The scenario analysis of three price trends examines whether or not the approach is beneficial to users. The sensitivity analysis then has been conducted using the financial option Greeks to assess the effects of changes in volatility in the total price of the option contracts. The total price of the Asian options was then compared with those of the European and American options.FindingsThe results demonstrate that the Asian option expenditure was about 1.87% of the total cost of the case study project. The scenario analysis revealed that, except for when the price followed a continuous downward pattern, the use of this type of financial instrument is a practical approach for steel pipeline price risk management.Practical implicationsThis approach is founded on a well-established financial options theory and elucidates how pipeline project participants can deploy Asian option contracts to safeguard against steel price fluctuations in practice.Originality/valueAlthough the literature exists about the theory and application of financial derivative instruments for risk management in other sectors, their application to the construction industry is infrequent. In the proposed methodology, all participants involved in fixed price pipeline projects readily surmount the risk of exposure to material price fluctuations.

Long distance pollen-mediated gene flow at a landscape level: the weed beet as a case study

2007 ◽  
Vol 16 (18) ◽  
pp. 3801-3813 ◽  
Author(s):  
STÉPHANE FÉNART ◽  
FRÉDÉRIC AUSTERLITZ ◽  
JOËL CUGUEN ◽  
JEAN-FRANÇOIS ARNAUD
Keyword(s):  
Gene Flow ◽  
Long Distance ◽  
Landscape Level

Basic communication sciences

1969 ◽  
Vol 308 (1493) ◽  
pp. 183-198
Keyword(s):  
Long Distance ◽  
Earth Station ◽  
Early Communication ◽  
Technical Developments ◽  
Radiated Power ◽  
The Earth ◽  
Distance Communication ◽  
Quality Of Transmission ◽  
Communication Equipment

The feasibility and utility of long-distance communication via Earth-orbiting satellites has been demonstrated during recent years and it is appropriate therefore to focus attention on the more important scientific studies and technical developments that will be needed if full use is to be made of this valuable mode of communication in the future. The early communication satellites (the Telstar and Relay series) were pioneers in a relatively unknown propagation environment. The satellites themselves were conceptually simple and the communication equipment consisted essentially of a frequency-changing transponder with an r. f. power output of a few watts and a bandwidth some tens of megahertz. Carrier frequencies in the range 2 to 6 GHz were employed; typically either 2 or 6 GHz was used for transmission and 4 GHz for reception at the Earth station. To obtain an adequate signal/noise ratio at the output of the Earth station receiver, frequency modulation was employed, the frequency deviations being greater than those used on terrestrial microwave links. Launcher limitations and other factors meant that the satellites had to be placed in inclined elliptical orbits (see figure 1) with maximum heights of only a few thousand miles. Nevertheless, these satellites demonstrated that some hundreds of frequency-division multiplex telephony circuits, or a television channel, could be achieved with generally satisfactory quality of transmission. It is to be noted, however, that the satellite transponders accommodated only one, or at the most two, r. f. carriers at any time, and that the transmission performance was at times marginal due to limitations of the satellite effective radiated power. Furthermore, these relatively low orbit satellites provided communication in periods of generally less than an hour at a time and required continuous tracking by the Earth station aerials, due to movement of the satellites relative to the Earth.

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