The Trans-Alaska Pipeline System Synthetically Insulated Workpad—An Evaluation of Present Conditions

1983 ◽  
Vol 105 (2) ◽  
pp. 230-235 ◽  
Author(s):  
E. S. Clarke ◽  
T. G. Krzewinski ◽  
M. C. Metz

The purpose of the insulated workpad study, described in the following paper, was twofold. First, the owners of the Trans-Alaska Pipeline System (TAPS) needed an evaluation of present conditions of the insulated pad to determine the feasibility of plans by builders of the Alaska Natural Gas Transportation System (ANGTS) to reuse the TAPS workpad for parallel construction. Secondly, since the integrity of the elevated support system used by TAPS in insulated workpad areas was dependent on the insulation maintaining a shallow active layer, it was important for Alyeska (the operator of TAPS) to be assured that the insulated pad was performing as designed. The fieldwork undertaken for the study included test pitting and probing to determine the depth of thaw, sampling the insulation, and installing thermistors for long-term temperature monitoring. The insulation samples were tested for several parameters. Total performance of the workpad was better than expected, although several types of problems were encountered. Most were related to construction practices or postconstruction activity.

1983 ◽  
Vol 48 (8) ◽  
pp. 2165-2174
Author(s):  
Karel Smrček ◽  
Martin Wedell ◽  
Jiří Mrha ◽  
Miroslava Musilová

From the ratio of hydrophobic to hydrophilic pore volumes determined after a long-term exposure of the gas or active layer to water, the strong hydrophobic nature of the teflonized carbon black contained in carbon-based gas diffusion electrodes was confirmed. This material proves better than Teflon in Teflon-bonded active carbon electrodes, whose hydrophobicity is adversely affected on heating and the mechanical strength of the layer decreases. Measurement of the penetration of water and rate of flow of oxygen revealed that the teflonized carbon black ensures two essential functions of the gas diffusion electrode: feeding the active layer with oxygen and prevention of flooding of the gas pores.


1994 ◽  
Vol 12 (2-3) ◽  
pp. 221-225
Author(s):  
Michael E.J. Phelps

Northeastern B.C. has several trillion cubic feet of established gas reserve and estimates of ultimate potential are as high as 50 tcf. Westcoast's current deliverability of 1.9 bcf/d is expected to rise by 30% over the next five years. Through-put on Westcoast's pipeline system reached 0.5 bcf/d in 1992. The new role of natural gas in the energy mix will lead to greater consumption such as in gas-fired cogeneration. The price will be “right” when supply and demand are evenly balanced.


2020 ◽  
pp. 431-434
Author(s):  
Oliver Arndt

This paper deals with the conversion of coke fired lime kilns to gas and the conclusions drawn from the completed projects. The paper presents (1) the decision process associated with the adoption of the new technology, (2) the necessary steps of the conversion, (3) the experiences and issues which occurred during the first campaign, (4) the impacts on the beet sugar factory (i.e. on the CO2 balance and exhaust gas temperature), (5) the long term impressions and capabilities of several campaigns of operation, (6) the details of available technologies and (7) additional benefits that would justify a conversion from coke to natural gas operation on existing lime kilns. (8) Forecast view to develop systems usable for alternative gaseous fuels (e.g. biogas).


Author(s):  
A. D. Chalfoun

Abstract Purpose of Review Anthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’ responses to development and summarize remaining gaps in knowledge. To do so, I evaluated the directionality of a wide variety of responses in relation to taxon, location, development type, development metric, habitat type, and spatiotemporal aspects. Recent Findings Studies (n = 70) were restricted to the USA and Canada, and taxonomically biased towards birds and mammals. Longer studies, but not those incorporating multiple spatial scales, were more likely to detect significant responses. Negative responses of all types were present in relatively low frequencies across all taxa, locations, development types, and development metrics but were context-dependent. The directionality of responses by the same species often varied across studies or development metrics. Summary The state of knowledge about wildlife responses to oil and natural gas development has developed considerably, though many biases and gaps remain. Studies outside of North America and that focus on herpetofauna are lacking. Tests of mechanistic hypotheses for effects, long-term studies, assessment of response thresholds, and experimental designs that isolate the effects of different stimuli associated with development, remain critical. Moreover, tests of the efficacy of habitat mitigation efforts have been rare. Finally, investigations of the demographic effects of development across the full annual cycle were absent for non-game species and are critical for the estimation of population-level effects.


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 758
Author(s):  
Fiona Esam ◽  
Rachel Forrest ◽  
Natalie Waran

The influence of the COVID-19 pandemic on human-pet interactions within New Zealand, particularly during lockdown, was investigated via two national surveys. In Survey 1, pet owners (n = 686) responded during the final week of the five-week Alert Level 4 lockdown (highest level of restrictions—April 2020), and survey 2 involved 498 respondents during July 2020 whilst at Alert Level 1 (lowest level of restrictions). During the lockdown, 54.7% of owners felt that their pets’ wellbeing was better than usual, while only 7.4% felt that it was worse. Most respondents (84.0%) could list at least one benefit of lockdown for their pets, and they noted pets were engaged with more play (61.7%) and exercise (49.7%) than pre-lockdown. Many respondents (40.3%) expressed that they were concerned about their pet’s wellbeing after lockdown, with pets missing company/attention and separation anxiety being major themes. In Survey 2, 27.9% of respondents reported that they continued to engage in increased rates of play with their pets after lockdown, however, the higher levels of pet exercise were not maintained. Just over one-third (35.9%) of owners took steps to prepare their pets to transition out of lockdown. The results indicate that pets may have enjoyed improved welfare during lockdown due to the possibility of increased human-pet interaction. The steps taken by owners to prepare animals for a return to normal life may enhance pet wellbeing long-term if maintained.


2021 ◽  
Vol 13 (2) ◽  
pp. 164
Author(s):  
Chuyao Luo ◽  
Xutao Li ◽  
Yongliang Wen ◽  
Yunming Ye ◽  
Xiaofeng Zhang

The task of precipitation nowcasting is significant in the operational weather forecast. The radar echo map extrapolation plays a vital role in this task. Recently, deep learning techniques such as Convolutional Recurrent Neural Network (ConvRNN) models have been designed to solve the task. These models, albeit performing much better than conventional optical flow based approaches, suffer from a common problem of underestimating the high echo value parts. The drawback is fatal to precipitation nowcasting, as the parts often lead to heavy rains that may cause natural disasters. In this paper, we propose a novel interaction dual attention long short-term memory (IDA-LSTM) model to address the drawback. In the method, an interaction framework is developed for the ConvRNN unit to fully exploit the short-term context information by constructing a serial of coupled convolutions on the input and hidden states. Moreover, a dual attention mechanism on channels and positions is developed to recall the forgotten information in the long term. Comprehensive experiments have been conducted on CIKM AnalytiCup 2017 data sets, and the results show the effectiveness of the IDA-LSTM in addressing the underestimation drawback. The extrapolation performance of IDA-LSTM is superior to that of the state-of-the-art methods.


Sign in / Sign up

Export Citation Format

Share Document