scholarly journals Predicting the External Corrosion Rate of X60 Pipeline Steel: A Mathematical Model

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 583
Author(s):  
Min Xu ◽  
Hongxing Liang ◽  
Yu Liu ◽  
Edouard Asselin
Keyword(s):  
Mathematical Model ◽  
Corrosion Rate ◽  
Pipeline Steel ◽  
Soil Conditions ◽  
Salt Composition ◽  
Wide Range ◽  
Soil Corrosivity ◽  
External Corrosion ◽  
The Individual ◽  
The Impact

The need for predicting pipeline service life and improving risk assessment relating to corrosion hazards requires establishing a correlation between the corrosion rate (CR) of pipeline steel and its coating condition, cathodic protection (CP) levels and surrounding soil conditions. This paper presents a systematic study of the CR of bare and coated—with and without a dent or holiday defect—X60 pipeline steel in simulated field environments. Three CP scenarios, i.e., no, optimized, and over-protection, were studied to cover a wide range of possible CP conditions that pipeline steel may encounter in the field. Two types of salt solutions (sodium chloride or sodium sulfate) with a variation of temperatures (10 °C, 40 °C, 65 °C) and pH values (2, 7, 12) were investigated to simulate different levels of soil corrosivity. A mathematical model was developed to reveal the impact of various parameters and their interactions on the CR of X60 steel. The coating condition was the most important factor. The individual effects of other factors including temperature, pH, salt composition and CP were not shown to be significant. Instead, the interactions between temperature and salt composition, and particularly the interaction between pH and CP appeared more important in determining the overall CR.

scholarly journals Earth-based observations of impact phenomena

1996 ◽  
Vol 156 ◽  
pp. 81-109
Author(s):  
Philip D. Nicholson
Keyword(s):  
Hubble Space Telescope ◽  
Common Pattern ◽  
Mid Infrared ◽  
Wide Range ◽  
Impact Phenomena ◽  
Infrared Wavelengths ◽  
Positive Correlations ◽  
The Individual ◽  
The Impact ◽  
Size Estimates

Earth-based observations at near- and mid-infrared wavelengths were obtained for at least 15 of the SL9 impacts, ranging from the spectacular G, K and L events to the barely-detected N and V impacts. Although there were a few exceptions, most of the IR lightcurves fit a common pattern of one or two relatively faint precursor flashes, followed several minutes later by the main infrared event as the explosively-ejected plume crashed down onto the jovian atmosphere. Correlations with the impact times recorded by the Galileo spacecraft and plumes imaged by the Hubble Space Telescope lead to an interpretation of the twin precursors in terms of (i) the entry of the bolide into the upper atmosphere, and (ii) the re-appearance of the rising fireball above Jupiter's limb. Positive correlations are observed between the peak IR flux observed during the splashback phase and both pre-impact size estimates for the individual SL9 fragments and the scale of the resulting ejecta deposits. None of the fragments observed to have moved off the main train of the comet by May 1994 produced a significant impact signature. Earth-based fireball temperature estimates are on the order of 750 K, 30-60 sec after impact. For the larger impacts, the unexpectedly protracted fireball emission at 2.3 μm remains unexplained. A wide range of temperatures has been inferred for the splashback phase, where shocks are expected to have heated the re-entering plume material at least briefly to several thousand K, and further modelling is required to reconcile these data.

scholarly journals Weak Land–Atmosphere Coupling Strength in HadAM3: The Role of Soil Moisture Variability

2005 ◽  
Vol 6 (5) ◽  
pp. 670-680 ◽  
Author(s):  
David M. Lawrence ◽  
Julia M. Slingo
Keyword(s):  
Boundary Layer ◽  
Soil Moisture ◽  
Coupling Strength ◽  
General Circulation ◽  
General Circulation Models ◽  
Soil Conditions ◽  
Wide Range ◽  
The Impact ◽  
Soil Moisture Variability ◽  
Moisture Variability

Abstract A recent model intercomparison, the Global Land–Atmosphere Coupling Experiment (GLACE), showed that there is a wide range of land–atmosphere coupling strengths, or the degree that soil moisture affects the generation of precipitation, amongst current atmospheric general circulation models (AGCMs). Coupling strength in the Hadley Centre atmosphere model (HadAM3) is among the weakest of all AGCMs considered in GLACE. Reasons for the weak HadAM3 coupling strength are sought here. In particular, the impact of pervasive saturated soil conditions and low soil moisture variability on coupling strength is assessed. It is found that when the soil model is modified to reduce the occurrence of soil moisture saturation and to encourage soil moisture variability, the soil moisture–precipitation feedback remains weak, even though the relationship between soil moisture and evaporation is strengthened. Composites of the diurnal cycle, constructed relative to soil moisture, indicate that the model can simulate key differences in boundary layer development over wet versus dry soils. In particular, the influence of wet or dry soil on the diurnal cycles of Bowen ratio, boundary layer height, and total heat flux are largely consistent with the observed influence of soil moisture on these properties. However, despite what appears to be successful simulation of these key aspects of the indirect soil moisture–precipitation feedback, the model does not capture observed differences for wet and dry soils in the daily accumulation of boundary layer moist static energy, a crucial feature of the feedback mechanism.

On Compressor Station Layout

2003 ◽  
Author(s):  
Rainer Kurz ◽  
Sebouh Ohanian ◽  
Matt Lubomirsky
Keyword(s):  
Gas Turbine ◽  
Electric Motor ◽  
Operating Conditions ◽  
Performance Characteristics ◽  
General Context ◽  
Operational Flexibility ◽  
Gas Engine ◽  
Wide Range ◽  
The Individual ◽  
The Impact

This paper discusses issues that influence the decision on the arrangement of compressors and the type of equipment in gas pipeline compressor stations. Different concepts such as multiple small units versus single large units are considered, both regarding their impact on the individual station and the overall pipeline. The necessity of standby units is discussed. Various concepts for drivers (gas turbine, gas motor and electric motor) and compressors (centrifugal and reciprocating) are analyzed. The importance of considering all possible operating conditions is stressed. With the wide range of possible operating conditions for the pipeline in mind, the discussion will be brought into the general context of operational flexibility, availability, reliability, installation issues, remote control, and operability of gas turbine driven centrifugal compressors compared to other solutions such as electric motor driven compressors or gas engine driven reciprocating compressors. The impact of different concepts on emissions and fuel cost is discussed. Among the assumptions in this paper are the performance characteristics of the compressor. It will be outlined how these performance characteristics influence the conclusions.

SOIL CONDITIONS OF FOREST VEGETATION GROWTH OF NORTHERN VOLGA

10.12737/3822 ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. 112-116
Author(s):  
Жубрин ◽  
Denis Zhubrin ◽  
Сабиров ◽  
Ayrat Sabirov
Keyword(s):  
Forest Soils ◽  
Forest Ecosystems ◽  
Biological Diversity ◽  
Basic Research ◽  
Economic Assessment ◽  
Forest Vegetation ◽  
Soil Conditions ◽  
Vegetation Growth ◽  
Wide Range ◽  
The Impact

Conducting soil studies are relevant in determining the subordination of forest types and biodiversity of vegetation to soil taxa, in determining the dependence of basic forest stand productivity from soil conditions, in creating a land registry and economic assessment of forest land, in studying the soil evolution of forest plantations under the impact of anthropogenic influences. Soil is the most important environmental factor in shaping the productivity and biodiversity of forest phytocenosis. The study of forest soils is also important in terms of basic research of their genesis, evolution. The article presents the results of research of soil conditions of vegetation growth of forest ecosystems of northern regions of Volga of the Republic of Tatarstan. The main types of forest soils are characterized in the paper. The studied forest formations grow on various soils on genesis and forest vegetation properties: sod-podzol, gray forest, brown forest, brown forest sandy, alluvial meadow, rendziny soil. The granulometric structure of soils varies from sandy to the clay. The well structured soils are formed on loamy layers under forest phytocenosis canopy. Pine and spruce ecosystems have a medi-decomposed litter of moder and multi-moder types; linden, oak, birch and aspen biogeocoenoses have strong-decomposed litter of multi type, that characterizes the intense biological cycle of substances in forest ecosystems. The wide range of place conditions of territories causes the biological diversity of forest vegetation at the level of species and ecosystems.

scholarly journals PLAYBACK-THEATRE IN THE SYSTEM OF SOCIALIZATION AND RE-SOCIALIZATION OF PERSONALITY

2018 ◽  
pp. 17-20
Author(s):  
M. Dergach
Keyword(s):  
Psychological Adaptation ◽  
Psychological Support ◽  
Psychological Climate ◽  
Psychological State ◽  
Wide Range ◽  
Important Means ◽  
The Common ◽  
Main Thing ◽  
The Individual ◽  
The Impact

The article reveals the peculiarities of playback theater as a psychodramatic technique, analyzes the current practice of using playback theater in the system of socialization and re-socialization. The author found that socialization, as a necessary process for interaction with the outside world, is manifested in the assimilation and appropriation of social experience for the purpose of productive functioning in it and to construct an image of the common and own world (as a part of the common), which allows a person to live a life while preserving individuality. and creatively influence the world. Within this provision, playback theater should be regarded as a technology of the paratheater system of dramatherapy, which is relevant at any stage of the socialization of the individual or as a means in the mechanisms of socialization. Playback theater contributes to the development of tolerance for social differences, the acceptance of another with all its features, values. Thanks to him, we learn to listen to understand others, because in the performance the main thing is the story of the viewer, the realization of which is impossible in reality without careful perception. The author has found that playback theater as a paratheater system of drama is a rather interesting and important means of socialization and re-socialization of the personality, it can be used in any group of people to solve problems of a wide range. The article describes in detail the content of the playback theater application, namely: social integration of individual subgroups into society; social and psychological adaptation of personality; social-psychological and therapeutic support for people who are in emotional and psychological state; creation of a more favorable social and psychological climate for the team; social and psychological support in complex events; development of personal qualities of children in educational institutions; social and psychological support of people in recreational activities; playback theater as a means of creating space for social networking. Prospects for further research on the topic of the article are to study the attitude of the audience to the performances of the playback theater, the search for the means of expression of the actors, the impact of playback on the children's audience.

Factors Contributing to the Occurrence of Leptospirosis, and the Impact on Public Health in Saint Lucia 2008-2019

2020 ◽  
Vol 8 (4) ◽  
pp. 69-78
Author(s):  
Edward L. Emmanuel
Keyword(s):  
Public Health ◽  
Secondary Data ◽  
Educational Programme ◽  
Easy Access ◽  
Bacterial Disease ◽  
Mortality And Morbidity ◽  
Wide Range ◽  
Saint Lucia ◽  
The Individual ◽  
The Impact

Leptospirosis is a bacterial disease that affects humans and animals. The causative agent is a spirochete of the genus Leptospira. In humans, it causes a wide range of symptoms, however, asymptomatic presentation is not uncommon. Without proper treatment, leptospirosis can lead to kidney damage, meningitis, liver failure, and respiratory distress. Death may occur in some patients. The aim of the study is to identify the factors contributing to the occurrence of leptospirosis, and the impact on public health in Saint Lucia 2008-2019. The study design is a mixed – method, comprising quantitative and qualitative data. A stratified sampling design using probability proportionate to size sampling at the settlement level was used. Secondary data on the incidence of leptospirosis were obtained from the Ministry of Health, and rainfall data were obtained from the Meteorology Office. Analysis of the data reveals several factors contributing to the occurrence of leptospirosis in Saint Lucia: poor garbage disposal; a large rodent population with easy access to garbage; and a lack of knowledge of leptospirosis. The impact on public health is manifested in the mortality and morbidity of individuals primarily men, and the health, social, and economic impact on the country. Reducing the impact of leptospirosis on the individual and country necessitates an island wide multi - sectoral control and prevention educational programme; an evaluation of the collection, storage, and disposal of household garbage; and the enforcement of legislation governing the proper collection, storage and disposal of garbage.

scholarly journals Emergence and establishment of native and non-native species in soils of remnant and converted highland grasslands – southern Brazil

2017 ◽  
Vol 17 (1) ◽  
Author(s):  
Helena de Lima Müller ◽  
Rodrigo Ramos Lopes ◽  
Julia-Maria Hermann
Keyword(s):  
Soil Type ◽  
Native Species ◽  
Seedling Emergence ◽  
Soil Conditions ◽  
Holcus Lanatus ◽  
Native Grasslands ◽  
Exotic Tree ◽  
Wide Range ◽  
Tussock Grass ◽  
The Impact

Abstract Native grasslands in the Campos de Cima da Serra, Brazil, are being converted at speed for exotic tree plantations and cropland. The impact of modified and novel soil conditions on the establishment of native grassland species is unknown; establishment of non-native species, deliberately or accidentally introduced, could be favoured. In a common garden composed of fully randomized replicate samples of soils collected from remnant grassland, former cropland and pine plantations, we tested emergence and establishment of five cold-season species: Native low-tussock grass Piptochaetium montevidense (Spreng.) Parodi; native legume Trifolium riograndense Burkart; naturalized low-tussock grass Vulpia bromoides (L.) Gray; low-tussock grass Holcus lanatus L., cultivated and naturalized in Brazil; and a cultivar of non-native Trifolium repens. Other than expected, soil type and species*soil type interactions had no significant effect on seedling emergence after 132 days in the field. Species effect on seedling emergence, however, was highly significant. Vulpia bromoides emergence was significantly highest in all soil types. Holcus lanatus and Trifolium riograndense both achieved second highest emergence rates and did not differ significantly from each other. Lowest overall emergence rates were found in the non-native clover cultivar. Lab germination tests failed for Piptochaetium, although it showed reasonable emergence in the field. Good performance of the native clover is encouraging for future grassland restoration, but the value of highly germinable Vulpia as a forage remains to be tested. Holcus tolerates a wide range of soil conditions and its life history traits may promote naturalization, or even invasiveness. Native grasslands of the region should be monitored for this species. Studies like these, but set up on a larger geographical scale and with a wider array of native species, will be essential in developing ecological restoration methods for southern Brazilian grasslands.

A Mathematical Model and Performance Evaluation for a Single-Stage Grid-Connected Photovoltaic (PV) System

2008 ◽  
Vol 9 (6) ◽  
Author(s):  
Prajna Paramita Dash ◽  
Amirnaser Yazdani
Keyword(s):  
Mathematical Model ◽  
Control Strategy ◽  
Voltage Control ◽  
Current Control ◽  
Operating Conditions ◽  
Single Stage ◽  
Control Loop ◽  
Pv System ◽  
Wide Range ◽  
The Impact

This paper proposes a control strategy for important transients of a single-stage, three-phase, PV system that is connected to a distribution network. The proposed control strategy adopts an inner current-control loop and an outer DC-link voltage control loop. The current-control mechanism renders the PV system protected against external faults, enables control of the DC-link voltage and, therefore, controls/maximizes the PV system power output. The paper also proposes a feed-forward compensation strategy for the DC-link voltage control loop to mitigate the impact of the nonlinear characteristic of the PV array on the closed-loop stability, and to permit design and optimization of the DC-link voltage controller for a wide range of operating conditions. A mathematical model and a control design methodology are presented for the PV system, and it is shown that under the proposed control, the PV system fulfills the operational requirements of a grid-connected PV system. The effectiveness of the proposed control strategy and the most important transients of the PV system are evaluated through simulation studies conducted on a detailed switched model of the PV system in the PSCAD/EMTDC software environment.

An Approximate Investigation of the Off-Design Performance of a Turbo-Compressor Stage

1949 ◽  
Vol 161 (1) ◽  
pp. 227-232 ◽  
Author(s):  
W. Merchant
Keyword(s):  
Mathematical Model ◽  
Tip Clearance ◽  
Simple Problem ◽  
Perfect Incompressible Fluid ◽  
Empirical Correction ◽  
Wide Range ◽  
Multistage Compressors ◽  
Turbo Compressor ◽  
The Individual ◽  
Flow Quantity

Turbine or compressor stages are often designed by comparison with a mathematical model with a perfect fluid and a particular flow quantity. Empirical correction factors are required for the various sources of discrepancy between the mathematical model and an actual stage, such as wall and blade friction losses and tip clearance losses, but such models are of considerable use as a basis of comparisons. In multistage compressors or turbines that are required to operate over a wide range of speeds and flow quantities, the individual stages are required to operate over a wide range of velocity ratios. So far no satisfactory model has been proposed for the effect of variation of flow quantity from the design conditions. This paper considers the simple problem of an isolated stage working in a long, parallel annulus with a perfect incompressible fluid.

scholarly journals The impact of the manager's emotional intelligence on organisational performance

2016 ◽  
Vol 38 (1) ◽  
pp. 58-69 ◽  
Author(s):  
Karolis Karolis
Keyword(s):  
Sustainable Development ◽  
Emotional Intelligence ◽  
Balanced Scorecard ◽  
Economic Indicators ◽  
Organisational Performance ◽  
Development Methodology ◽  
Wide Range ◽  
The Individual ◽  
The Impact

The problem dealt with in the paper is the impact of manager's emotional intelligence (EI) on the economic, social, and ecological sides of the organisational activity and the qualitative criteria of the evaluation of the organisational performance from the viewpoint of sustainable development (SD) of the organisation. The aim of the paper is to justify the interrelationship of the EI of the manager of an organization and the performance of the organization in terms of its sustainable development. Methodology: to evaluate EI, the methodology proposed by J. N. Hall (2005) was adopted as a basis, by means of which the EI of the respondents – the heads of eight organisations that provided a wide range of services (logistics, ICT, etc.) – has been measured. To evaluate the effectiveness of the organisational performance, the indicators of effectiveness proposed by R. S. Kaplan and D. P. Norton (1992, 2001) and supplemented by the author – a balanced scorecard (BS) – has been applied. It was established that, in the evaluation of any organisation, the existing BS of economic indicators should be supplemented by social-cultural and environmental instruments. The EI of managers was found to be closely related both to the individual indicators of the organisational performance and with the integrated BS.

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