scholarly journals Mesoscale Assimilation of Radial Velocities from Doppler Radars in a Preoperational Framework

2009 ◽  
Vol 137 (6) ◽  
pp. 1939-1953 ◽  
Author(s):  
Thibaut Montmerle ◽  
Claudia Faccani
Keyword(s):  
Three Dimensional ◽  
Radial Velocities ◽  
Horizontal Wind ◽  
Low Level ◽  
Convective Systems ◽  
Daily Monitoring ◽  
The Status ◽  
Quality Checks

Abstract This paper presents the results of a preoperational assimilation of radial velocities from Doppler radars of the French Application Radar la Météorologie InfraSynoptique (ARAMIS) network in the nonhydrostatic model, the Application of Research to Operations at Mesoscale (AROME). For this purpose, an observation operator, which allows the simulation of radial winds from the model variables, is included in the three-dimensional variational data assimilation (3DVAR) system. Several data preprocessing procedures are applied to avoid as much as possible erroneous measurements (e.g., due to dealiasing failures) from entering the minimization process. Quality checks and other screening procedures are discussed. Daily monitoring diagnostics are developed to check the status and the quality of the observations against their simulated counterparts. Innovation biases in amplitude and in direction are studied by comparing observed and simulated velocity–azimuth display (VAD) profiles. Experiments over 1 month are performed. Positive impacts on the analyses and on precipitation forecasts are found. Scores against conventional data show mostly neutral results because of the much-localized impact of radial velocities in space and in time. Significant improvements of low-level divergence analysis and on the resulting forecast are found when specific sampling conditions are met: the closeness of convective systems to radars and the orientation of the low-level horizontal wind gradient with respect to the radar beam. Focus on a frontal rainband case study is performed to illustrate this point.

scholarly journals The Ecological Footprint Accounting of Products: When Larger Is Not Worse

Resources ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 65 ◽  
Author(s):  
Nicoletta Patrizi ◽  
Valentina Niccolucci ◽  
Riccardo Pulselli ◽  
Elena Neri ◽  
Simone Bastianoni
Keyword(s):  
Environmental Impact ◽  
Ecological Footprint ◽  
Three Dimensional ◽  
Product System ◽  
Sustainability Evaluation ◽  
Competitive Systems ◽  
The Status ◽  
Resource Accounting ◽  
Selection Of

One of the main goals of any (sustainability) indicator should be the communication of a clear, unambiguous, and simplified message about the status of the analyzed system. The selected indicator is expected to declare explicitly how its numerical value depicts a situation, for example, positive or negative, sustainable or unsustainable, especially when a comparison among similar or competitive systems is performed. This aspect should be a primary and discriminating issue when the selection of a set of opportune indicators is operated. The Ecological Footprint (EF) has become one of the most popular and widely used sustainability indicators. It is a resource accounting method with an area based metric in which the units of measure are global hectares or hectares with world average bio-productivity. Its main goal is to underline the link between the (un)sustainability level of a product, a system, an activity or a population life style, with the land demand for providing goods, energy, and ecological services needed to sustain that product, system, activity, or population. Therefore, the traditional rationale behind the message of EF is: the larger EF value, the larger environmental impact in terms of resources use, the lower position in the sustainability rank. The aim of this paper was to investigate if this rationale is everywhere opportune and unambiguous, or if sometimes its use requires paying a special attention. Then, a three-dimensional modification of the classical EF framework for the sustainability evaluation of a product has been proposed following a previous work by Niccolucci and co-authors (2009). Finally, the potentialities of the model have been tested by using a case study from the agricultural context.

Model maturity towards modeling and simulation: Concepts, index system framework and evaluation method

2020 ◽  
Vol 11 (03) ◽  
pp. 2040001
Author(s):  
Lin Zhang ◽  
Ying Liu ◽  
Yuanjun Laili ◽  
Weicun Zhang
Keyword(s):  
Index System ◽  
Evaluation System ◽  
Evaluation Method ◽  
Quality Model ◽  
Simulation Fidelity ◽  
The Status ◽  
Hierarchical Evaluation ◽  
Quality Evaluation System

Simulation has become an essential way and sometimes the only way to study complex systems (e.g., system of systems, SoS). Simulation is the model-based activity. How to build a high-quality model is the first consideration in simulation. Fidelity and credibility are the two mostly used metrics to evaluate the quality of a model. However, the definitions and evaluation methods of fidelity and credibility vary from one research to another and it’s hard to evaluate the metrics precisely. More importantly, the evolution process of a model in use cannot be directly reflected by the two metrics. Therefore, this paper introduces the model maturity to track the status of a model during its life cycle, especially in the use and management phases, which will be an important supplement to the quality evaluation system of models. The concept of model maturity is given and a framework of index system for model maturity evaluation is established. Then, a hierarchical evaluation method based on qualitative and quantitative analysis (HEQQ) for model maturity is proposed. Finally, a case study is used to validate the feasibility and effectiveness of the proposed method.

A Modeling Study of a Low-Level Jet along the Yun-Gui Plateau in South China

2016 ◽  
Vol 55 (1) ◽  
pp. 41-60 ◽  
Author(s):  
Ming-Yang He ◽  
Hong-Bo Liu ◽  
Bin Wang ◽  
Da-Lin Zhang
Keyword(s):  
South China ◽  
Large Scale ◽  
Model Simulation ◽  
Three Dimensional ◽  
Radiative Heating ◽  
Horizontal Wind ◽  
Maximum Speed ◽  
Pressure System ◽  
Low Level ◽  
Low Level Jet

AbstractIn this study, the three-dimensional structures and diurnal evolution of a typical low-level jet (LLJ) with a maximum speed of 24 m s−1 occurring in the 850–800-hPa layer are examined using both large-scale analysis and a high-resolution model simulation. The LLJ occurred on the eastern foothills of the Yun-Gui Plateau in south China from 1400 LST 29 June to 1400 LST 30 June 2003. The effects of surface radiative heating, topography, and latent heat release on the development of the LLJ case are also studied. Results show that a western Pacific Ocean subtropical high and a low pressure system on the respective southeast and northwest sides of the LLJ provide a favorable large-scale mean pressure pattern for the LLJ development. The LLJ reaches its peak intensity at 850 hPa near 0200 LST with wind directions veering from southerly before sunset to southwesterly at midnight. A hodograph at the LLJ core shows a complete diurnal cycle of the horizontal wind with a radius of 5.5 m s−1. It is found that in an LLJ coordinates system the along-LLJ geostrophic component regulates the distribution and 65% of the intensity of LLJ, whereas the ageostrophic component contributes to the clockwise rotation, thus leading to the formation and weakening of the LLJ during night- and daytime, respectively. Numerical sensitivity experiments confirm the surface radiative heating as the key factor in determining the formation of the nocturnal LLJ. The existence of the Yun-Gui Plateau, and the downstream condensational heating along the mei-yu front play secondary roles in the LLJ formation.

scholarly journals Estimation and Mapping of Hurricane Turbulent Energy Using Airborne Doppler Measurements

2010 ◽  
Vol 138 (9) ◽  
pp. 3656-3670 ◽  
Author(s):  
Sylvie Lorsolo ◽  
Jun A. Zhang ◽  
Frank Marks ◽  
John Gamache
Keyword(s):  
Boundary Layer ◽  
Three Dimensional ◽  
Turbulent Energy ◽  
Vertical Shear ◽  
Horizontal Wind ◽  
Horizontal Shear ◽  
Retrieval Method ◽  
Hurricane Boundary Layer

Abstract Hurricane turbulent kinetic energy (TKE) was computed using airborne Doppler measurements from the NOAA WP-3D tail radars, and TKE data were retrieved for a variety of storms at different stages of their life cycle. The geometry of the radar analysis coupled with the relatively small beam resolution at ranges <8 km allowed for the estimation of subkilometer turbulent processes. Two-dimensional profiles of TKE were constructed and revealed that the strongest turbulence was generally located in convective regions, such as the eyewall, with magnitudes often exceeding 15 m2 s−2 and in the boundary layer with values of 5–10 m2 s−2 in the lowest kilometer. A correlation analysis showed that the strong turbulence was generally associated with strong horizontal shear of vertical and radial wind components in the eyewall and strong vertical shear of horizontal wind in the boundary layer. Mean vertical profiles of TKE decrease sharply above the hurricane boundary layer and level off at low magnitude for all regions outside the radius of maximum wind. The quality of the retrieval method was evaluated and showed very good agreement with TKE values directly calculated from the three-dimensional wind components of in situ measurements. The method presented here provides a unique opportunity to assess hurricane turbulence throughout the storm, especially in high-wind regions, and can be applied on extensive datasets of past and future airborne hurricane penetrations.

scholarly journals Quality Assessment of Milling Pavement Surface Using 3D Line Laser Technology

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Bing Hui ◽  
Mu Guo ◽  
Xiaofang Liu
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
Poor Quality ◽  
Surface Model ◽  
Premature Failure ◽  
Quality Work ◽  
Milled Surface ◽  
Surface Assessment

To ensure that a regular milled surface texture provides good bonding without residual distress, a new specification of milling surface assessment has been established for quantitatively evaluating the milled surface quality. This research explores the possibility of using three-dimensional (3D) laser scanning technology to develop an algorithm to obtain a milled surface model that can measure evaluating indicators, milling depth and texture depth, and identify poorly milled areas. A case study was conducted by using a laser scanning vehicular system to collect 3D continuous pavement transverse profiles data in a 500 m long segment of Highway S107. The results show that the proposed method is very promising and can measure the milling depth and texture depth to effectively and quantitatively differentiate between good- (milling depth between 47 mm and 53 mm and texture depth exceeding 2 mm) and poor-quality work. Moreover, the poorly milled areas such as those with residual distress and unmilled areas that will lead to premature failure can also be identified using the proposed method. The proposed method can effectively support remilling work and ensure the quality of the overlay pavement.

scholarly journals Environment Associated with Deep Moist Convection under SALLJ Conditions: A Case Study

2010 ◽  
Vol 25 (3) ◽  
pp. 970-984 ◽  
Author(s):  
Paloma Borque ◽  
Paola Salio ◽  
Matilde Nicolini ◽  
Yanina García Skabar
Keyword(s):  
Frontal Zone ◽  
Mesoscale Convective Systems ◽  
South American ◽  
Moist Convection ◽  
Low Level ◽  
Convective Systems ◽  
Mesoscale Convective ◽  
Low Level Jet ◽  
Deep Moist Convection

Abstract The present work focuses on the study of the environmental conditions preceding the development of a group of subtropical mesoscale convective systems over central and northern Argentina on 6–7 February 2003 during the South American Low Level Jet Experiment. This period was characterized by an extreme northerly low-level flow along the eastern Andes foothills [South American low-level jet (SALLJ)]. The entire studied episode was dominated by the presence of a very unstable air mass over northern Argentina and a frontal zone near 40°S. The SALLJ generated an important destabilization of the atmosphere due to the strong humidity and differential temperature advection. Orography provided an extra lifting motion to the configuration of the regional wind field, which was efficient in forcing the initiation of convection. Once convection developed, it moved and regenerated in regions where the convective instability was horizontally homogeneous and stronger.

scholarly journals Characteristics of Vertical Velocity Cores in Different Convective Systems Observed over Gadanki, India

2009 ◽  
Vol 137 (3) ◽  
pp. 954-975 ◽  
Author(s):  
K. N. Uma ◽  
T. Narayana Rao
Keyword(s):  
Deep Convection ◽  
Horizontal Wind ◽  
Air Velocity ◽  
Low Level ◽  
Convective Systems ◽  
Vertical Extent ◽  
Mesoscale Convective ◽  
Data Points ◽  
Radar Measurements ◽  
High Level

Abstract The Indian mesosphere–stratosphere–troposphere (MST) radar measurements during the passage of 60 convective systems are used to study the vertical air velocity (w) characteristics of tropical convection. The up- and downdraft cores and various stages/types of convection (shallow, deep, and decaying) are discerned from radar time–intensity maps of w. The characteristics of cores (speed, size, orientation, vertical extent, gravity wave activity, etc.) at different stages of convection are discussed with the help of three case studies. The cores stratified based on the type of convection are mostly erect in nature in all types of convective systems, except for deep updraft cores. A considerable percentage (35%) of deep updraft cores show inclined structure with elevation angles as low as 0°–20°. The variation of the horizontal wind field with height and the internal dynamics of mesoscale convective systems (MCSs) are thought to be responsible for this geometry. Further, the vertical extent of draft cores is limited in all types of convection, except for deep updraft cores. About 77% of deep updraft cores have a vertical extent greater than 10 km and ∼23% of these cores reach an altitude of 16 km. The size (overpass time) of the core shows an increasing trend with altitude up to 10–12 km and then decreases. Among different types of convection, the size of core is larger for deep updraft cores and smaller for shallow updraft cores. The variation of w distribution with height is different for different convection categories. The mode (and also the mean) of the distribution shows low-level descent (below 3 km) and mid–high-level ascent in shallow and deep convection categories, while nearly uniform distribution is seen in decaying convection. Strong updrafts are seen in deep convective systems in the upper troposphere (of the order of 15–20 m s−1), followed by shallow and decaying systems, while downdrafts are generally weaker in all types of convection. The variability (within the cores and also with altitude) and the number of data points are larger in updraft cores than in downdraft cores corresponding to shallow and deep convection. Contrasting the composite w profile at Gadanki with those obtained elsewhere revealed interesting features: the absence of subsidence at higher levels, the presence of low-level subsidence, a single ascent peak in the middle troposphere, etc. Further, the magnitude of composite w derived from wind profiler measurements is larger than that obtained with other techniques.

scholarly journals Improvement of Service Quality in the Supply Chain of Commercial Banks—A Case Study in Vietnam

2021 ◽  
Vol 14 (8) ◽  
pp. 357
Author(s):  
Han-Khanh Nguyen ◽  
Thuy-Dung Nguyen
Keyword(s):  
Service Quality ◽  
Commercial Banks ◽  
Three Dimensional ◽  
Sustainable Growth ◽  
Factors Affecting ◽  
Business Operations ◽  
Improve Service Quality

The outbreak of the Covid-19 pandemic caused a serious impact on the business activities of enterprises and households, affecting the operation of banks around the world, especially for capital mobilization from those with savings deposits at commercial banks. In face of the unpredictable developments of the pandemic, many services of banks in Vietnam were also affected, so it has been necessary to make a plan to maintain business operations and respond effectively to these difficulties. In this study, the authors used three research models to form a three-dimensional frame of reference (past, present, and future) to identify, analyze, and evaluate the factors affecting the service quality of commercial banks’ savings deposit mobilization, and to suggest solutions that can minimize risks and improve customer satisfaction for savings deposits at commercial banks, improve service quality to avoid potential long-term risks, as well as maintain sustainable growth and social stability in the future.

scholarly journals A case study of a low level jet during OPALE

2014 ◽  
Vol 14 (22) ◽  
pp. 31091-31109 ◽  
Author(s):  
H. Gallée ◽  
H. Barral ◽  
E. Vignon ◽  
C. Genthon
Keyword(s):  
Three Dimensional ◽  
East Antarctica ◽  
Low Level ◽  
Thermal Wind ◽  
Flat Terrain ◽  
Dimensional Version ◽  
Low Level Jet ◽  
Oxidant Production

Abstract. A case study of a low level jet during the OPALE (Oxidant Production over Antarctic Land and its Export) summer campaign is presented. It has been observed at Dome C (East Antarctica) and is simulated accurately by the three-dimensional version of the Modèle Atmosphérique Régional (MAR). It is found that this low level jet is not related to an episode of thermal wind, conforting that Dome C may be a~place where turbulence on flat terrain can be studied.

scholarly journals Enhancing The Role of Business in Transferring Research Results into Agriculture: Case Study in Moc Chau District, Son La Province

2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Ngo Thi Phuong Quy
Keyword(s):  
Focal Point ◽  
Research Results ◽  
The Past ◽  
Local Agriculture ◽  
Technological Advances ◽  
Key Factor ◽  
The Status

In recent years, Vietnam’s agriculture has developed strongly thanks to the application of scientific and technological advances in production. Business is a key factor in attracting investment, expanding markets for agricultural products, and an important focal point for transferring research results into agriculture. Based on the assessment of the status of transferring research results into agriculture in Moc Chau district, Son La province over the past time, the paper proposes views and solutions to enhance the role of business in promoting the transfer of research results in local agriculture such as tax favors for business, linkages between business and researchers and enhance the quality of human resources.

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