scholarly journals The use of relaxation methods in the WRF model for the analysis of meteorological conditions in Ukraine over a long period

2020 ◽  
Vol 2 ◽  
pp. 30-42
Author(s):  
O.V. Khalchenkov ◽  
◽  
I.V. Kovalets ◽  
Keyword(s):  
Large Scale ◽  
Mesoscale Model ◽  
Soil Layer ◽  
Meteorological Conditions ◽  
Optimal Combination ◽  
Relaxation Methods ◽  
Advantages And Disadvantages ◽  
Long Period ◽  
Surface Measurements

The possibility of using grid and spectral relaxation methods and other options in the WRF mesoscale model for long-term continuous calculations has been investigated. Results of comparison of selected me-teorological parameters with surface measurements are presented. The basic recommendations for select-ing the optimal combination of long-term calculation parameters are given. The use of the selected param-eters allowed to obtain continuous meteorological fields over a long period (several months), which are well consistent with surface measurements, retain large scale synoptic structures and have a deviation from measurements commensurate with the results of short-term simulations over corresponding time peri-od. The selected optimal combination of parameters allowed us to perform continuous calculation for the period from January 1, 2019 to November 6, 2019 without accumulating errors. In a long-run calculation of meteorological conditions in Ukraine with spatial resolution 0.15 deg. for a temperature at a height of 2 meters was obtained a mean absolute error of MAE=2,05 ºC, a correlation coefficient of Corr=0,97, for a wind speed at a height of 10 meters of MAE=1.4 m/s, of Corr=0,75, and for a wind direction at a height of 10 meters of MAE=24,6 degrees, Corr=0,66. The influence of the parametrizations of the underlying sur-face and the active soil layer on the quality of calculation of meteorological fields is studied. Using the option to update the water surface temperature allowed to reduce the MAE for the temperature from 2,17 ºС to 2,05 ºС. Each of the investigated surface models showed its advantages and disadvantages. The pa-rameterizations RUC and NOAH LSM showed good agreement with the measurements for all studied pa-rameters and can be recommended for use in long-term continuous calculations. A long calculation made it possible to describe the process of accumulation and melting of snow correctly, and made it possible to reproduce the temperature of the upper soil layer correctly as well. The paper shows that the disadvantage of long- term calculations is the inability to determine the temperature of the lower layers of the soil cor-rectly.

A Review of Downhole Wireless Technologies and Improvements

2021 ◽  
Author(s):  
Brett Bouldin ◽  
Ahmed AlShmakhy ◽  
Ahmed Khaled Bazuhair ◽  
Muzoon Hasan Alzaabi ◽  
Jarl André Fellinghaug
Keyword(s):  
Wireless Communication ◽  
Flow Rate ◽  
Large Scale ◽  
Pressure Pulse ◽  
Cost Effective ◽  
Directional Drilling ◽  
Wireless Technologies ◽  
Advantages And Disadvantages ◽  
Wireless Telemetry

Abstract Downhole wireless communication in the form of mud pulse telemetry enabled directional drilling over the past 60 years and has been hugely successful. Technologies like Measurement While Drilling (MWD), Logging While Drilling (LWD), and Geosteering would simply not exist without it. But in the Production and Producing end of the business, applications for downhole wireless communication have been less clear, especially where long distances and long-term monitoring are concerned. Several wireless technologies are in use today for long-term production applications. Electromagnetic (EM), acoustic, and pressure pulse telemetries are finding application as wireless production gauges, drill stem test tools, and drilling alternatives to pressure pulse. But the large-scale vision of, "Breaking the Wire!" in production wells has not yet occurred. Permanent Downhole Gauges (PDG) with an umbilical to surface are still the product of choice for long-term production monitoring. A history of wireless approaches in production applications will be given and the different methods used in the industry will be explained. A comparison and contrast of wireless telemetry methods will be explored, explained, and evaluated. Advantages and disadvantages will be listed for each approach. A ranking system will be employed to illustrate the evaluation results of the different wireless telemetry methods. New variants for wireless telemetry, power supplies, and measurement methods will be proposed. Preferred applications for each gauge type will be given. Downhole gauges can be improved by integrating pressure pulse, a downhole power generator, and downhole flow rate measurement into a single unit. The overall size can be ten times shorter than existing systems while still generating a larger wireless signal. Such a system would make wireless downhole gauges much more practical and should significantly increase their uptake in the industry. Real-time measurement of downhole pressure and downhole flow rate transforms the accuracy and effectiveness of Pressure Transient Analysis (PTA). Better reservoir understanding can be gained by using only drawdown tests, without shutting in the well. Smaller tools are generally more cost effective.

Seismic Isolation Retrofit for Large-Scale Government Building Identified as Cultural Assets

2009 ◽  
Vol 4 (3) ◽  
pp. 199-207 ◽  
Author(s):  
Takao Nishizawa ◽  
Keyword(s):  
Seismic Isolation ◽  
Large Scale ◽  
Seismic Retrofitting ◽  
Disaster Prevention ◽  
Prevention Measures ◽  
Distant Future ◽  
Long Period ◽  
Earthquake Resistant ◽  
Resistant Structure

The Aichi Prefectural Government building in Nagoya, designated a national registered cultural asset and an important disaster prevention facility, was found in 2002 to be seismically inadequate for anticipated earthquakes. While seismic retrofitting has been considered, however, no report has, to our knowledge, compared retrofitting alternatives in depth. The building is located in a Nagoya district scheduled for disaster prevention measures anticipating the Tokai and Tonankai earthquakes - two “super shakers” expected to devastate major Japanese cities, including Tokyo, and decimate the urban population in the not too distant future. These quakes are expected to produce long-term earthquake movement with amplified long-period components and to damage long-period structures such as skyscrapers and base-isolated buildings. In 2003, we selected seismic retrofitting as the optimum answer given the prefectural building’s features. We made objective comparisons working with academic experts and, in 2004, jointly examined the building using simulated earthquake motion based on the latest knowledge and data, making the main building a highly earthquake-resistant structure. This paper reports our findings and the aftermath of recommendations. The building appearance and building structure conception diagram are shown in Fig. 1.

scholarly journals Review of Wind Models at a Local Scale: Advantages and Disadvantages

2021 ◽  
Vol 9 (3) ◽  
pp. 318
Author(s):  
Felix P. Martinez-García ◽  
Antonio Contreras-de-Villar ◽  
Juan J. Muñoz-Perez
Keyword(s):  
Large Scale ◽  
Near Field ◽  
Wind Farms ◽  
Local Scale ◽  
Data Driven ◽  
Future Scenarios ◽  
Global Circulation ◽  
Advantages And Disadvantages ◽  
Global Circulation Models

Wind forecasts are widely spread because of the growth in wind power, but also because there are other applications to consider, such as the long-term scenario forecasts regarding the effects of global warming. Overall, there have been big developments in global circulation models (GCM) that inform future scenarios at the large scale, but wind forecast at a local scale is a problem that has not totally been solved. It should be possible to estimate the winds in the near field with a certain accuracy, which is interesting for aspects such as the blowing of incident wind at wind farms, the wind on a dune in movement, or the wind blowing in a harbour. Therefore, a data-driven wind transference equation at a local scale is needed. Among the conclusions, it is worthy to state that the statistical downscaling techniques are suitable for application as a statistical inference at small scales. The aim of this paper is therefore to review the current methods and techniques used and show the different methodologies and their applications in the field. Additional targets will be to identify the advantages, disadvantages, or limitations of the current models at the local scale and propose research to find possible improvements.

scholarly journals NMR Spectroscopy for Metabolomics Research

Metabolites ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 123 ◽  
Author(s):  
Abdul-Hamid Emwas ◽  
Raja Roy ◽  
Ryan T. McKay ◽  
Leonardo Tenori ◽  
Edoardo Saccenti ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Large Scale ◽  
Analytical Techniques ◽  
Advantages And Disadvantages ◽  
Nmr Techniques ◽  
Tissue Specimens ◽  
High Level ◽  
Lower Limits

Over the past two decades, nuclear magnetic resonance (NMR) has emerged as one of the three principal analytical techniques used in metabolomics (the other two being gas chromatography coupled to mass spectrometry (GC-MS) and liquid chromatography coupled with single-stage mass spectrometry (LC-MS)). The relative ease of sample preparation, the ability to quantify metabolite levels, the high level of experimental reproducibility, and the inherently nondestructive nature of NMR spectroscopy have made it the preferred platform for long-term or large-scale clinical metabolomic studies. These advantages, however, are often outweighed by the fact that most other analytical techniques, including both LC-MS and GC-MS, are inherently more sensitive than NMR, with lower limits of detection typically being 10 to 100 times better. This review is intended to introduce readers to the field of NMR-based metabolomics and to highlight both the advantages and disadvantages of NMR spectroscopy for metabolomic studies. It will also explore some of the unique strengths of NMR-based metabolomics, particularly with regard to isotope selection/detection, mixture deconvolution via 2D spectroscopy, automation, and the ability to noninvasively analyze native tissue specimens. Finally, this review will highlight a number of emerging NMR techniques and technologies that are being used to strengthen its utility and overcome its inherent limitations in metabolomic applications.

scholarly journals Large-Scale Synoptic Systems and Fog During the C-FOG Field Experiment

2021 ◽  
Author(s):  
Clive E. Dorman ◽  
Sebastian W. Hoch ◽  
Ismail Gultepe ◽  
Qing Wang ◽  
Ryan T. Yamaguchi ◽  
...  
Keyword(s):  
Large Scale ◽  
Longwave Radiation ◽  
Meteorological Conditions ◽  
Cloud Base ◽  
Atlantic Canada ◽  
The North ◽  
Coastal Fog ◽  
Surface Measurements ◽  
Avalon Peninsula ◽  
Cloud Base Height

AbstractThe goal of this work is to summarize synoptic meteorological conditions during the Coastal Fog (C-FOG) field project that took place onshore and offshore of the Avalon Peninsula, Newfoundland, from 25 August until 8 October 2018. Visibility was measured at three locations at the Ferryland supersite that are about 1 km from each other, and at two additional sites 66 and 76 km to the north. Supporting meteorological measurements included surface winds, air temperature, humidity, pressure, radiation, cloud-base height, and atmospheric thermodynamic profiles from radiosonde soundings. Statistics are presented for surface measurements during fog events including turbulence kinetic energy, net longwave radiation, visibility, and precipitation. Eleven fog events are observed at Ferryland. Each significant fog event is related to a large-scale cyclonic system. The longest fog event is due to interaction of a northern deep low and a tropical cyclone. Fog occurrence is also examined across Atlantic Canada by including Sable Island, Yarmouth, Halifax, and Sydney. It is concluded that at Ferryland, all significant fog events occur under a cyclonic system while at Sable Island all significant fog events occur under both cyclonic and anticyclonic systems. The fog-formation mechanism involves cloud lowering and stratus broadening or only stratus broadening for the cyclonic systems while for the anticyclonic systems it is stratus broadening or radiation. Although widely cited as the main cause of fog in Atlantic Canada, advection fog is not found to be the primary or sole fog type in the events examined.

scholarly journals Study on soil moisture by thermal infrared data

2013 ◽  
Vol 17 (5) ◽  
pp. 1375-1381 ◽  
Author(s):  
Jun He ◽  
Xiao-Hua Yang ◽  
Shi-Feng Huang ◽  
Chong-Li Di ◽  
Ying Mei
Keyword(s):  
Soil Moisture ◽  
Large Scale ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Soil Layer ◽  
Growth Period ◽  
Vegetation Growth ◽  
Term Monitoring ◽  
Infrared Data

Information on soil moisture is important for environment management. This study bases on the daily observation to study the normalized difference vegetation index and to classify the index data. The results indicate that: (1) the index is able to adequately reflect the changes of soil moisture content in 10 cm and 20 cm thickness of soil layer during the vegetation growth period and (2) Information on soil moisture can be used for regional drought monitoring. The method can be extended for long-term monitoring of droughts over large-scale regions.

Kompensationsgeschäfte der DDR - Instrumente einer europäischen Ost-West-Wirtschaftsintegration?

2008 ◽  
Vol 49 (2) ◽  
Author(s):  
Matthias Judt
Keyword(s):  
Large Scale ◽  
East Germany ◽  
The West ◽  
Trade Relations ◽  
Advantages And Disadvantages ◽  
East German ◽  
Potential Losses ◽  
Foreign Commerce ◽  
Investment Goods

AbstractThe article deals with the issue of countertrades, GDR foreign commerce enterprises contracted with western firms in order to secure the modernizing of its economy. It discusses the argument of whether those contracts could establish new forms of European East-Westintegration between Comecon and EEC economies.Starting from rather unfavorable general trading conditions in the 1950s and early 1960s, East Germany could intensify its trade relations with western countries in the late 1960s. Based on its international recognition in the late 1960s and early 1970s, it also got easier access to western credits to finance large-scale investment programs in the economy. With varying success and in order to refinance those imports from the West, GDR officials tried to conclude contracts pre-engaging western partners to accept mandatory deliveries by East German enterprises in return. The author defines three major forms of such contracts, distinguishable by the level and the type of GDR counter deliveries, agreed on by the contracting partners.Since East Germany failed to put through high levels of its own counter deliveries, these projects contributed to its long-term indebtedness. Moreover, this kind of business, unintentionally created potential losses in the GDR’s foreign trade firms due to various factors. Western companies themselves started to market East German products received in fulfillment of countertrade contracts. Western deliverers of investment goods managed to secure higher prices for their deliveries and lower ones for East German goods in order to subsidize the marketing of East German products they had taken over. That put additional pressure on the already decreasing competitiveness of East German export goods. Finally, the article presents a judgment on the advantages and disadvantages of the countertrade concept for East Germany itself.

scholarly journals Long-term analysis of carbon dioxide and methane column-averaged mole fractions retrieved from SCIAMACHY

2010 ◽  
Vol 10 (11) ◽  
pp. 27479-27522 ◽  
Author(s):  
O. Schneising ◽  
M. Buchwitz ◽  
M. Reuter ◽  
J. Heymann ◽  
H. Bovensmann ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Large Scale ◽  
Near Infrared ◽  
Retrieval Algorithm ◽  
Steady Increase ◽  
Absorption Bands ◽  
Longitudinal Gradients ◽  
Surface Measurements ◽  
Concentration Changes

Abstract. Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic greenhouse gases contributing to global climate change. SCIAMACHY onboard ENVISAT (launch 2002) was the first and is now together with TANSO onboard GOSAT (launch 2009) the only satellite instrument currently in space whose measurements are sensitive to CO2 and CH4 concentration changes in the lowest atmospheric layers where the variability due to sources and sinks is largest. We present long-term SCIAMACHY retrievals (2003–2009) of column-averaged mole fractions of both gases (denoted XCO2 and XCH4) derived from absorption bands in the near-infrared/shortwave-infrared (NIR/SWIR) spectral region focusing on large-scale features. The results are obtained using an upgraded version (v2) of the retrieval algorithm WFM-DOAS including several improvements, while simultaneously maintaining its high processing speed. The retrieved mole fractions are compared to global model simulations (CarbonTracker XCO2 and TM5 XCH4) being optimised by assimilating highly accurate surface measurements from the NOAA/ESRL network and taking the SCIAMACHY averaging kernels into account. The comparisons address seasonal variations and long-term characteristics. The steady increase of atmospheric carbon dioxide primarily caused by the burning of fossil fuels can be clearly observed with SCIAMACHY globally. The retrieved annual mean XCO2 increase over both hemispheres agrees with CarbonTracker within the error bars but is on average somewhat smaller (1.8 ppm yr−1 compared to 1.9 ppm yr−1). The amplitude of the XCO2 seasonal cycle as retrieved by SCIAMACHY, which is 4.3 ppm for the Northern Hemisphere and 1.4 ppm for the Southern Hemisphere, is on average about 1 ppm larger than for CarbonTracker. An investigation of the boreal forest carbon uptake during the growing season via the analysis of longitudinal gradients shows good agreement between SCIAMACHY and CarbonTracker concerning the overall magnitude of the gradients and their annual variations. The retrieved XCH4 results show that after years of stability, atmospheric methane has started to rise again in recent years which is consistent with surface measurements. The largest increase is observed for the tropics and northern mid- and high-latitudes amounting to about 8 ppb yr−1 since 2007. Due care has been exercised to minimise the influence of detector degradation on the quantitative estimate of this anomaly.

scholarly journals Long-term analysis of carbon dioxide and methane column-averaged mole fractions retrieved from SCIAMACHY

2011 ◽  
Vol 11 (6) ◽  
pp. 2863-2880 ◽  
Author(s):  
O. Schneising ◽  
M. Buchwitz ◽  
M. Reuter ◽  
J. Heymann ◽  
H. Bovensmann ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Boreal Forest ◽  
Large Scale ◽  
Retrieval Algorithm ◽  
Steady Increase ◽  
Absorption Bands ◽  
Longitudinal Gradients ◽  
Surface Measurements ◽  
Concentration Changes

Abstract. Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic greenhouse gases contributing to global climate change. SCIAMACHY onboard ENVISAT (launch 2002) was the first and is now with TANSO onboard GOSAT (launch 2009) one of only two satellite instruments currently in space whose measurements are sensitive to CO2 and CH4 concentration changes in the lowest atmospheric layers where the variability due to sources and sinks is largest. We present long-term SCIAMACHY retrievals (2003–2009) of column-averaged dry air mole fractions of both gases (denoted XCO2 and XCH4) derived from absorption bands in the near-infrared/shortwave-infrared (NIR/SWIR) spectral region focusing on large-scale features. The results are obtained using an upgraded version (v2) of the retrieval algorithm WFM-DOAS including several improvements, while simultaneously maintaining its high processing speed. The retrieved mole fractions are compared to global model simulations (CarbonTracker XCO2 and TM5 XCH4) being optimised by assimilating highly accurate surface measurements from the NOAA/ESRL network and taking the SCIAMACHY averaging kernels into account. The comparisons address seasonal variations and long-term characteristics. The steady increase of atmospheric carbon dioxide primarily caused by the burning of fossil fuels can be clearly observed with SCIAMACHY globally. The retrieved global annual mean XCO2 increase agrees with CarbonTracker within the error bars (1.80±0.13 ppm yr−1 compared to 1.81±0.09 ppm yr−1). The amplitude of the XCO2 seasonal cycle as retrieved by SCIAMACHY, which is 4.3±0.2 ppm for the Northern Hemisphere and 1.4±0.2 ppm for the Southern Hemisphere, is on average about 1 ppm larger than for CarbonTracker. An investigation of the boreal forest carbon uptake during the growing season via the analysis of longitudinal gradients shows good agreement between SCIAMACHY and CarbonTracker concerning the overall magnitude of the gradients and their annual variations. The analysis includes a discussion of the relative uptake strengths of the Russian and North American boreal forest regions. The retrieved XCH4 results show that after years of stability, atmospheric methane has started to rise again in recent years which is consistent with surface measurements. The largest increase is observed for the tropics and northern mid- and high-latitudes amounting to about 7.5±1.5 ppb yr−1 since 2007. Due care has been exercised to minimise the influence of detector degradation on the quantitative estimate of this anomaly.

Evolution of Large-Scale Coronal Structures

1994 ◽  
Vol 144 ◽  
pp. 29-33
Author(s):  
P. Ambrož
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Large Scale ◽  
Coronal Magnetic Field ◽  
Source Surface ◽  
Solar Cycles ◽  
Characteristic Relationship ◽  
The Magnetic Field ◽  
Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

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