Effect of Environmental Factors on the Performance Characteristics of an Oil Cooling System Designed for a Turbo-Shaft Engine

2009 ◽  
Author(s):  
R. K. Mishra ◽  
A. K. Mishra ◽  
G. Gouda
Keyword(s):  
Environmental Factors ◽  
Environmental Conditions ◽  
Coastal Area ◽  
Power Loss ◽  
Cooling System ◽  
Performance Characteristics ◽  
System Level ◽  
High Humidity ◽  
Acceptable Limit ◽  
Loss And Damage

High rotor speeds of turbo-shaft engines demand an efficient oil cooling system to keep the bearing temperature within the acceptable limit. This makes the oil cooling system to play an important part in engine lubrication circuit and any malfunction or inefficiency of the system will lead to rotor instability and seizure causing power loss and damage to the engine. An oil cooling system has been designed for a 900 kW class turbo-shaft engine. It has undergone system level tests to study the effect of various environmental conditions such as sand ingestion during desert operation, prolong exposure to high humidity and salt-laden atmosphere during marine/coastal area operation, and with growth of fungus on external surfaces, etc. The paper presents the tolerance of the oil cooling system to different adverse environmental factors and highlights their effect on the performance characteristics of the system.

scholarly journals Regional environmental controllers influence continental scale soil carbon stocks and future carbon dynamics

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Ruiz Potma Gonçalves ◽  
Umakant Mishra ◽  
Skye Wills ◽  
Sagar Gautam
Keyword(s):  
Environmental Factors ◽  
Land Cover ◽  
Environmental Conditions ◽  
Climate Feedback ◽  
Soil Types ◽  
Climatic Data ◽  
Earth System ◽  
Land Cover Types ◽  
Continental Scale ◽  
Soc Stocks

AbstractUnderstanding the influence of environmental factors on soil organic carbon (SOC) is critical for quantifying and reducing the uncertainty in carbon climate feedback projections under changing environmental conditions. We explored the effect of climatic variables, land cover types, topographic attributes, soil types and bedrock geology on SOC stocks of top 1 m depth across conterminous United States (US) ecoregions. Using 4559 soil profile observations and high-resolution data of environmental factors, we identified dominant environmental controllers of SOC stocks in 21 US ecoregions using geographically weighted regression. We used projected climatic data of SSP126 and SSP585 scenarios from GFDL-ESM 4 Earth System Model of Coupled Model Intercomparison Project phase 6 to predict SOC stock changes across continental US between 2030 and 2100. Both baseline and predicted changes in SOC stocks were compared with SOC stocks represented in GFDL-ESM4 projections. Among 56 environmental predictors, we found 12 as dominant controllers across all ecoregions. The adjusted geospatial model with the 12 environmental controllers showed an R2 of 0.48 in testing dataset. Higher precipitation and lower temperatures were associated with higher levels of SOC stocks in majority of ecoregions. Changes in land cover types (vegetation properties) was important in drier ecosystem as North American deserts, whereas soil types and topography were more important in American prairies. Wetlands of the Everglades was highly sensitive to projected temperature changes. The SOC stocks did not change under SSP126 until 2100, however SOC stocks decreased up to 21% under SSP585. Our results, based on environmental controllers of SOC stocks, help to predict impacts of changing environmental conditions on SOC stocks more reliably and may reduce uncertainties found in both, geospatial and Earth System Models. In addition, the description of different environmental controllers for US ecoregions can help to describe the scope and importance of global and local models.

Emerging investigator series: interacting effects of environmental factors on Daphnia magna removal of Escherichia coli from wastewater

2021 ◽  
Vol 7 (4) ◽  
pp. 726-738
Author(s):  
Seyyed M. H. Abtahi ◽  
Ojaswi Aryal ◽  
Niveen S. Ismail
Keyword(s):  
Escherichia Coli ◽  
Environmental Factors ◽  
Daphnia Magna ◽  
Environmental Conditions ◽  
E Coli

Zooplankton can significantly impact E. coli inactivation in wastewater, but inactivation rates are dependent on environmental conditions.

scholarly journals Contributions of Dopamine-Related Genes and Environmental Factors to Highly Sensitive Personality: A Multi-Step Neuronal System-Level Approach

PLoS ONE ◽  
2011 ◽  
Vol 6 (7) ◽  
pp. e21636 ◽  
Author(s):  
Chunhui Chen ◽  
Chuansheng Chen ◽  
Robert Moyzis ◽  
Hal Stern ◽  
Qinghua He ◽  
...  
Keyword(s):  
Environmental Factors ◽  
System Level ◽  
Neuronal System ◽  
Highly Sensitive

scholarly journals REDUCING THE INFLUENCE OF ENVIRONMENTAL FACTORS ON THE BENDING DEFORMATION OF CURED CARBON FIBER BY MICROWAVE PROCESSING

2021 ◽  
pp. 56-58
Author(s):  
I. V. Zlobina
Keyword(s):  
Electromagnetic Field ◽  
Composite Materials ◽  
Carbon Fiber ◽  
Environmental Factors ◽  
Flux Density ◽  
Environmental Conditions ◽  
Climatic Factors ◽  
Transverse Load ◽  
Bending Deformation ◽  
Energy Flux Density

The article discusses the results of a study of bending deformation and creep under transverse load of cured polymer composite materials (PCM), which were located for 8 months in full-scale environmental conditions in Saratov. It was found that being under the influence of natural climatic factors for the specified time leads to an increase in the bending deformation of samples from 13,5 to 25,4%, depending on the load. Processing in a microwave electromagnetic field with a frequency of 2450 MHz with an energy flux density of (17-18) x10 mW / cm for 2 minutes reduces bending deformation by (9-18)%, and creep - up to 4 times.

In vitro studies on the induction of sporogenous tissue on leaves of cinnamon fern. I. Environmental factors

1972 ◽  
Vol 50 (12) ◽  
pp. 2673-2682 ◽  
Author(s):  
William H. Harvey ◽  
James D. Caponetti
Keyword(s):  
Environmental Factors ◽  
Light Intensity ◽  
Environmental Conditions ◽  
Light Exposure ◽  
Progressive Increase ◽  
Light Phase ◽  
Sporogenous Tissue ◽  
Light Darkness

Intact, set III, cinnamon fern cataphyll and frond primordia, which were shown to have no predisposition to fertility in situ, produced sporangia when excised and cultured under sterile conditions in Knudson's medium supplemented with various levels of sucrose and maintained on 11 different regimens of light, darkness, and temperature for 10 weeks. Increasing levels of sucrose resulted in increased fertility under all environmental conditions, but the highest percentage of fertility was obtained under conditions of continuous dark at 26 °C. As the length of the light phase of the photoperiods decreased, a progressive increase in induction of fertile leaves was observed, suggesting that periods of long light exposure are inhibitory to the initiation of sporangia. Conversely, as the light intensity was increased, an inhibition of sporophyll differentiation occurred. Sporangia excised from dark-induced sporophylls and cultured in the light produced viable spores which germinated yielding haploid gametophytes that ultimately produced sporophytes.

Bioeroding sponge assemblages: the importance of substrate availability and sediment

2018 ◽  
Vol 99 (2) ◽  
pp. 343-358 ◽  
Author(s):  
Joseph Marlow ◽  
Christine H.L. Schönberg ◽  
Simon K. Davy ◽  
Abdul Haris ◽  
Jamaluddin Jompa ◽  
...  
Keyword(s):  
Coral Reef ◽  
Environmental Factors ◽  
Spatial Variation ◽  
Environmental Conditions ◽  
Sponge Species ◽  
Coral Mortality ◽  
Substrate Availability ◽  
Abiotic Conditions ◽  
Assemblage Composition ◽  
Reef Health

Despite global deterioration of coral reef health, not all reef-associated organisms are in decline. Bioeroding sponges are thought to be largely resistant to the factors that stress and kill corals, and are increasing in abundance on many reefs. However, there is a paucity of information on how environmental factors influence spatial variation in the distribution of these sponges, and how they might be affected by different stressors. We aimed to identify the factors that explained differences in bioeroding sponge abundance and assemblage composition, and to determine whether bioeroding sponges benefit from the same environmental conditions that can contribute towards coral mortality. Abundance surveys were conducted in the Wakatobi region of Indonesia on reefs characterized by different biotic and abiotic conditions. Bioeroding sponges occupied an average of 8.9% of available dead substrate and variation in abundance and assemblage composition was primarily attributed to differences in the availability of dead substrate. Our results imply that if dead substrate availability increases as a consequence of coral mortality, bioeroding sponge abundance is also likely to increase. However, bioeroding sponge abundance was lowest on a sedimented reef, despite abundant dead substrate. This suggests that not all forms of coral mortality will benefit all bioeroding sponge species, and sediment-degraded reefs are likely to be dominated by a few resilient bioeroding sponge species. Overall, we demonstrate the importance of understanding the drivers of bioeroding sponge abundance and assemblage composition in order to predict possible impacts of different stressors on reefs communities.

Modern problems of regionalization of territories and human adaptation in regions with extreme natural and climatic conditions

2021 ◽  
Author(s):  
A.L. Maksimov
Keyword(s):  
Environmental Factors ◽  
Environmental Conditions ◽  
Allostatic Load ◽  
Climatic Conditions ◽  
Extreme Conditions ◽  
Human Adaptation ◽  
Nonspecific Resistance ◽  
Key Words Adaptation ◽  
High Level ◽  
Selection Of

The paper considers modern approaches to the zoning of territories and the selection of people for life in extreme environmental conditions, taking into account modern geopolitical challenges. It is shown that it is possible, based on the allostasis concept, to conduct not only the selection of persons with a high level of nonspecific resistance, but also to quantify the degree of extremity of environmental factors using the standard represpiration test. Key words: adaptation, extreme conditions, selection, hypoxia, cold, rerespiration, allostatic load.

scholarly journals Diversity and Preference of Habitat Violin Crabs in Mangrove Areas Pancer Cengkrong Trenggalek Regency, East Java

2019 ◽  
Vol 17 (1) ◽  
pp. 82
Author(s):  
Niken Sawitri ◽  
Sunarto Sunarto ◽  
Prabang Setyono
Keyword(s):  
Environmental Factors ◽  
Natural Resource ◽  
Environmental Conditions ◽  
Diversity Index ◽  
Aquatic Biota ◽  
Vegetation Density ◽  
Mangrove Area ◽  
Living Things ◽  
Mangrove Vegetation ◽  
Mangrove Roots

ABSTRAKMangrove merupakan suatu ekosistem yang khas dan menjadi sumber daya alam yang sangat berperan penting dalam keberlangsungan makhluk hidup. Salah satunya melibatkan faktor lingkungan perairan mangrove yang dapat menyebabkan kesuburan diperairan sehingga banyak ditemukannya biota air yang hidup di kawasan tersebut, salah satunya adalah kepiting biola. Tujuan penelitian ini ialah untuk mengetahui keanekaragaman kepiting biola yang hidup di kawasan mangrove Pancer. Penelitian ini dilaksanakan pada bulan November-Desember 2017 di mangrove Pancer Cengkrong Kabupaten Trenggalek, Jawa timur. Dari penelitian ini ditemukan 7 jenis kepiting biola, yaitu Uca rosea, U.annulipes, U.forcipata, U.crassipes, U.vomeris, U.lactea dan U.paradussumieri. Tujuh spesies kepiting biola menempati beberapa tipe habitat yaitu, substart berpasir, substrat berlumpur, berlumpur dan berpasir, sekitar akar mangrove, serta akar mangrove yang berpasir. Indeks keanekaragaman kepiting biola di kawasan mangrove bagian stasiun 1 (3,4) tergolong tinggi, stasiun 2 (1,8), dan stasiun 3 (1,3) tergolong sedang. Kondisi lingkungan yang ada di seluruh stasiun relatif baik untuk kehidupan vegetasi mangrove dan kepiting biola. Kondisi tersebut ialah pH 7-9, suhu 27-31, salinitas 21,6 ppt, oksigen terlarut 5,5-8 mg/L, dan substrat lumpur berpasir. Kesimpulan dari penelitian ini ialah kerapatan vegetasi mangrove sangat berkaitan dengan kelimpahan jenis (kepadatan) kepiting biola serta banyaknya spesies di dalam suatu komunitas akan mempengaruhi keanekaragaman ekosistem yang ada di kawasan mangrove Pancer. Kata kunci : Kepiting biola, mangrove, keanekaragaman, TrenggalekABSTRACTMangroves are a unique ecosystem and become a natural resource that plays an important role in the survival of living things. One of them involves the environmental factors of mangrove waters that can cause fertility in the waters so that many aquatic biota are found in the area, one of which is a violin crab. The purpose of this study was to determine the diversity of violin crabs that live in the Pancer mangrove area. This research was carried out in November to Desember 2017 in the mangrove Pancer Cengkrong Trenggalek Regency, East Java. The results found seven types of violin crabs, namely Uca rosea, U.annulipes, U.forcipata, U.crassipes, U.vomeris, U.lactea and U.paradussumieri. seven species of violin crabs occupy several types of habitats, namely sandy substrates, muddy substrate, muddy and sandy, around mangrove roots, and sandy mangrove roots. Diversity index of violin crabs in the station 1 (3,4) mangrove area classified as high, station 2 (1,8), and station 2 (1,3) classified as medium. The environmental conditions in al stations are relatively good for the life of mangrove vegetation and violin crabs. These conditions are pH 7-9, temperature 27-32, salinity 21.6 ppt, dissolved oxygen 5.5-8 mg/L, and sandy mud substrate. The conclusion of this study is that mangrove vegetation density is closely related to the abundance of species (density) of violin crabs and the number of species in a community will affect the diversity of ecosystems in the Pancer mangrove area.Keywords: Violin Crab, Mangrove, Diversity, Trenggalek

High Power-Density SiC Converter

2008 ◽  
Vol 600-603 ◽  
pp. 1223-1226 ◽  
Author(s):  
Shin Ichi Kinouchi ◽  
Hiroshi Nakatake ◽  
T. Kitamura ◽  
S. Azuma ◽  
S. Tominaga ◽  
...  
Keyword(s):  
Power Density ◽  
High Power ◽  
Power Loss ◽  
Cooling System ◽  
High Power Density ◽  
Loss Reduction ◽  
Effective Volume ◽  
Similar Rating ◽  
Power Densities ◽  
System Volume

A compact SiC converter having power densities about 9 W/cm3 is designed and fabricated. It is confirmed that the converter operates in a thermally permissive range. The power loss of the module of the converter measured under motor operations is less than 50% of the similar-rating Si module loss. The shrink of the effective volume of DC-link capacitor is necessary to achieve the high power-density SiC converter, in addition to the decrease of the cooling system volume due to the loss reduction caused by SiC devices.

scholarly journals Development of MILIONCAST, an Improved Model for Predicting Downy Mildew Sporulation on Onions

Plant Disease ◽  
2004 ◽  
Vol 88 (7) ◽  
pp. 695-702 ◽  
Author(s):  
Tijs Gilles ◽  
Kath Phelps ◽  
John P. Clarkson ◽  
Roy Kennedy
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Temporal Pattern ◽  
Random Model ◽  
Controlled Environment ◽  
High Humidity ◽  
Potted Plants ◽  
Effects Of Temperature ◽  
Improved Model ◽  
Accuracy Of Prediction

The effects of temperature and relative humidity on Peronospora destructor sporulation on onion (Allium cepa) leaves were studied under controlled environmental conditions. Sporangia were produced most rapidly at 8 to 12°C after 5 h of high humidity during dark periods. The greatest number of sporangia was produced at 100% relative humidity (RH), and sporulation decreased to almost nil when humidity decreased to 93% RH. A model, named MILIONCAST (an acronym for MILdew on onION foreCAST), was developed based on the data from these controlled environment studies to predict the rate of sporulation in relation to temperature and relative humidity. The accuracy of prediction of sporulation was evaluated by comparing predictions with observations of sporulation on infected plants in pots outdoors. The accuracy of MILIONCAST was compared with the accuracy of existing models based on DOWNCAST. MILIONCAST gave more correct predictions of sporulation than the DOWNCAST models and a random model. All models based on DOWNCAST were more accurate than the random model when compared on the basis of all predictions (including positive and negative predictions), but they gave fewer correct predictions of sporulation than the random model. De Visser's DOWNCAST and ONIMIL improved their accuracy of prediction of sporulation events when the threshold humidity for sporulation was reduced to 92% RH. The temporal pattern of predicted sporulation by MILIONCAST generally corresponded well to the pattern of sporulation observed on the outdoor potted plants at Wellesbourne, UK.

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