Forced Convective Aggregation

2020 ◽  
Author(s):  
Beth Dingley ◽  
Guy Dagan ◽  
Philip Stier
Keyword(s):  
Diabatic Heating ◽  
Monsoon Season ◽  
Radiative Properties ◽  
Aerosol Model ◽  
Low Level ◽  
Heating Source ◽  
Wide Range ◽  
The Difference ◽  
High Level ◽  
The Impact

<p>The phenomenon of convective aggregation in idealised radiative convective equilibrium simulations has the ability to change the mean state of its domain. When compared to non-aggregation conditions, these simulations usually have warmer drier mean atmospheres, with stronger precipitation in the convective areas. Many of these idealised experiments use a fixed sea surface temperature (SST), where higher temperatures generally increase the scale of aggregation. SST gradients have been shown to organise convection, yet there has been no work done to investigate the impact of heating perturbations in the air on the aggregation of convection. Here we investigate how strong diabatic heating of the atmospheric column affect the existence and properties of convective aggregation. These perturbations provide a link to studying the effect of large pollution plumes on convection, for example during the Indian monsoon season.</p><p>An aerosol model is used to insert plumes of strongly absorbing aerosols into aquaplanet, non-rotating, global RCE simulations. We study the sensitivity of the response to aerosol optical depth (AOD) and aerosol radiative properties under different SSTs.</p><p>Without any forcing, the simulations at low SST do not aggregate while at high SST they do. We also see that adding the forcing causes aggregation at both temperatures for a wide range of AODs. Detailed investigation shows that the diabatic heating source causes two circulations to develop, one with low-level convergence towards the plume and high-level divergence away from the plume. A secondary circulation works tangentially to the plume, again with low-level convergence and high-level divergence, driving the formation of several radial branches of aggregated convection. We argue that, as we see this aggregation for plumes with realistic AODs, this could be an analogue for real-world organisation during high pollution events. Future work will investigate the difference in mechanisms between forced and unforced convective aggregation as well as conducting similar experiments in smaller, cloud resolving domains.</p>

scholarly journals A CloudSat–CALIPSO View of Cloud and Precipitation Properties across Cold Fronts over the Global Oceans

2015 ◽  
Vol 28 (17) ◽  
pp. 6743-6762 ◽  
Author(s):  
Catherine M. Naud ◽  
Derek J. Posselt ◽  
Susan C. van den Heever
Keyword(s):  
Large Scale ◽  
Cold Front ◽  
Conveyor Belt ◽  
Low Level ◽  
Scale Parameters ◽  
Convective Clouds ◽  
Cold Fronts ◽  
Surface Front ◽  
High Level ◽  
The Impact

Abstract The distribution of cloud and precipitation properties across oceanic extratropical cyclone cold fronts is examined using four years of combined CloudSat radar and CALIPSO lidar retrievals. The global annual mean cloud and precipitation distributions show that low-level clouds are ubiquitous in the postfrontal zone while higher-level cloud frequency and precipitation peak in the warm sector along the surface front. Increases in temperature and moisture within the cold front region are associated with larger high-level but lower mid-/low-level cloud frequencies and precipitation decreases in the cold sector. This behavior seems to be related to a shift from stratiform to convective clouds and precipitation. Stronger ascent in the warm conveyor belt tends to enhance cloudiness and precipitation across the cold front. A strong temperature contrast between the warm and cold sectors also encourages greater post-cold-frontal cloud occurrence. While the seasonal contrasts in environmental temperature, moisture, and ascent strength are enough to explain most of the variations in cloud and precipitation across cold fronts in both hemispheres, they do not fully explain the differences between Northern and Southern Hemisphere cold fronts. These differences are better explained when the impact of the contrast in temperature across the cold front is also considered. In addition, these large-scale parameters do not explain the relatively large frequency in springtime postfrontal precipitation.

scholarly journals A Two-Level Sound Classification Platform for Environmental Monitoring

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Stelios A. Mitilineos ◽  
Stelios M. Potirakis ◽  
Nicolas-Alexander Tatlas ◽  
Maria Rangoussi
Keyword(s):  
Cultural Heritage ◽  
Organizational Innovation ◽  
Gaussian Mixture ◽  
Low Level ◽  
Heritage Sites ◽  
Acoustic Sensor Networks ◽  
Preventive Actions ◽  
Integrated Platform ◽  
High Level ◽  
The Impact

STORM is an ongoing European research project that aims at developing an integrated platform for monitoring, protecting, and managing cultural heritage sites through technical and organizational innovation. Part of the scheduled preventive actions for the protection of cultural heritage is the development of wireless acoustic sensor networks (WASNs) that will be used for assessing the impact of human-generated activities as well as for monitoring potentially hazardous environmental phenomena. Collected sound samples will be forwarded to a central server where they will be automatically classified in a hierarchical manner; anthropogenic and environmental activity will be monitored, and stakeholders will be alarmed in the case of potential malevolent behavior or natural phenomena like excess rainfall, fire, gale, high tides, and waves. Herein, we present an integrated platform that includes sound sample denoising using wavelets, feature extraction from sound samples, Gaussian mixture modeling of these features, and a powerful two-layer neural network for automatic classification. We contribute to previous work by extending the proposed classification platform to perform low-level classification too, i.e., classify sounds to further subclasses that include airplane, car, and pistol sounds for the anthropogenic sound class; bird, dog, and snake sounds for the biophysical sound class; and fire, waterfall, and gale for the geophysical sound class. Classification results exhibit outstanding classification accuracy in both high-level and low-level classification thus demonstrating the feasibility of the proposed approach.

scholarly journals The Impact of CEOs' Compensations on Cost Stickiness in Industrial Companies Listed on the Amman Stock Exchange

2021 ◽  
Vol 15 (1) ◽  
pp. 152
Author(s):  
Lina Fuad Hussien
Keyword(s):  
Stock Exchange ◽  
Industrial Companies ◽  
Level Of Activity ◽  
Cost Behavior ◽  
Study Population ◽  
The Difference ◽  
High Level ◽  
The Cost ◽  
The Impact ◽  
Cost Stickiness

The purpose of this study is to analyze the asymmetry in cost behavior (cost stickiness) and to identify the impact of CEOs' compensation on the degree of cost stickiness behavior. The study population consists of the public shareholding companies listed on the ASE, which number (56) industrial company. Data were collected from (35) industrial companies for the period (2009 - 2019). To measure the degree of costs stickiness, The Model of Weiss (2010) was used. The Model of Weiss (2010) takes into account the costs and changes in the level of activity (sales) for the last four quarters of the company, Weiss (2010) model constructs the difference in logarithmic ratios of changes in cost. The study found that the CEO's compensation in Jordanian industrial companies consists of two forms. The companies pay fixed salaries or performance-related bonuses. The study found that the form of compensation that is paid to the CEO affects the behavior of managers. The results indicated that the performance-related rewards are accompanied by a decrease in the level of cost stickiness, and the compensation paid in the form of fixed salaries are accompanied by a high level of cost stickiness. The study recommends that companies should understand the role of the compensation form in administrative decisions, especially with regard to resource modifications, as management motives in relation to resource modifications must be taken into account because of their clear and direct impact on the cost structure of companies.

scholarly journals The effects of grouping types on promoting critical thinking in EFL collaborative writing

2020 ◽  
Vol 9 (2) ◽  
pp. 108-120
Author(s):  
Nguyen Thi Minh Tram ◽  
Bui Thi Thuc Quyen
Keyword(s):  
Critical Thinking ◽  
Collaborative Learning ◽  
Tertiary Education ◽  
Collaborative Writing ◽  
Homogeneous Groups ◽  
Learning And Teaching ◽  
Low Level ◽  
Heterogeneous Groups ◽  
High Level ◽  
The Impact

Nurturing critical thinking (CT) has been acknowledged as a core objective of tertiary education, and drawn attention from academia of teaching English as a Foreign Language (EFL), particularly in EFL argumentative writing. It has been claimed that collaborative learning which stimulates the active exchange of ideas within small groups not only increases interest among the participants but also promotes critical thinking. One of the important aspects of learning and teaching through collaboration is the group composition or grouping “who with whom”. The present study was an attempt to investigate the impact of homogeneous and heterogeneous groupings on critical thinking in collaborative writing. Having been required to write an argumentative essay as a pre-test, 75 participants, who were categorized by their prior critical thinking levels, were assigned into three group types: heterogeneous, homogeneous high and homogeneous low groups. As a consequence, four types of students were considered their improvement before and after the experiment: high-level students in heterogeneous groups, lowlevel students in heterogeneous groups, high-level students in homogeneous groups, low-level students in homogeneous groups. The results demonstrated that learners improved their critical thinking level through collaborative writing, whether working with stronger or weaker peers. However, heterogeneous grouping showed superiority over homogeneous grouping at the low level. The results revealed that cooperative learning could be especially beneficial for low students. It is hoped that the findings of the present study will give teachers deep insights into group compositions in collaborative learning courses, and will help them make better group experiences for students.

scholarly journals The Effect of Attribute Alignability on Product Purchase: The Moderating Role of Product Familiarity and Self-Construal

2021 ◽  
Vol 12 ◽  
Author(s):  
Yong Zhang ◽  
Yuwen Wen ◽  
Min Hou
Keyword(s):  
Structural Alignment ◽  
Personal Characteristics ◽  
Product Positioning ◽  
Self Construal ◽  
The Difference ◽  
Product Familiarity ◽  
High Level ◽  
The Impact ◽  
Moderating Role

Previous studies on the Structural Alignment Model suggest that people compare the alignable attributes and nonalignable attributes during the decision-making process and preference formation process. Alignable attributes are easier to process and more effective in clue extracting. Thus, it is believed that people rely more on alignable than nonalignable attributes when comparing alternatives. This article supposes that consumers’ product experience and personal characteristics also play a significant role in regulating consumers’ reliance on attribute alignability. The authors conducted three experiments to examine the moderating role of consumers’ product familiarity and self-construal in the impact of attribute alignability on consumer product purchase. The results show the following: (1) When making a purchase decision, consumers with a high level of product familiarity will rely more on nonalignable attributes, while those with a low level of product familiarity will rely more on alignable attributes. (2) The difference in consumer dependency on attribute alignability is driven by their perceived diagnosticity of attributes. (3) The dependency of consumers with different levels of familiarity on attribute alignability will be further influenced by consumers’ self-construal. Individuals with interdependent self-construal rely more on alignable attributes when unfamiliar with the product, while relying more on nonalignable attributes when familiar with the product. Individuals with independent self-construal, however, rely more on nonalignable attributes regardless of the degree of product familiarity. The conclusions of this paper can be used as references for enterprises to establish product positioning and communication strategies.

scholarly journals Static Profiling of Assembly Code Performance and Optimization Effectiveness using Instructions Performed and Program Latency

2019 ◽  
Vol 8 (2S8) ◽  
pp. 1463-1468
Keyword(s):  
Assembly Language ◽  
Optimization Method ◽  
Program Optimization ◽  
Low Level ◽  
Code Performance ◽  
Execution Speed ◽  
The Difference ◽  
And Performance ◽  
High Level ◽  
Optimization And Performance

Software program optimization for improved execution speed can be achieved through modifying the program. Programs are usually written in high level languages then translated into low level assembly language. More coverage of optimization and performance analysis can be performed on low level than high level language. Optimization improvement is measured in the difference in program execution performance. Several methods are available for measuring program performance are classified into static approaches and dynamic approaches. This paper presents an alternative method of more accurately measuring code performance statically than commonly used code analysis metrics. New metrics proposed are designed to expose effectiveness of optimization performed on code, specifically unroll optimizations. An optimization method, loop unroll is used to demonstrate the effectiveness of the increased accuracy of the proposed metric. The results of the study show that measuring Instructions Performed and Instruction Latency is a more accurate static metric than Instruction Count and subsequently those based on it.

scholarly journals Effect of Interventional Programme on Enhancing Empowerment Status through Decision Making Skills of Tribal Working Women in Utnoor Mandal Adilabad District, India

2021 ◽  
pp. 41-45
Author(s):  
N. Sandhya Rani ◽  
M. Sarada Devi
Keyword(s):  
Decision Making ◽  
Working Women ◽  
Total Sample ◽  
Average Level ◽  
Sample Population ◽  
Test Results ◽  
Low Level ◽  
Tribal Women ◽  
High Level ◽  
The Impact

Empowerment of tribal women is one of the central issues in the process of development all over the world. Empowerment is the process that allows one to gain the knowledge and attitude needed to cope with the changing world and the circumstances in which one lives [1]. Women empowerment is a process in which women gain greater share of control over material, human and intellectual resources as well as control over decision-making in their home, community, society and nation. Given the need to analyze the empowerment status of tribal women, the present study aimed to enhance the empowerment status through enhancing decision-making skills of tribal working women in India. The specific objective is to study the impact of intervention on enhancing status of empowerment through decision-making skills of tribal working women in Utnoor Mandal Adilabad district. The total sample population for the study was 50 tribal working women, and data was analyzed using a paired t test. Results revealed that at pretest, majority of the women were at average level of decision-making skills (78%), 12% were at low level and only 10% were at high level. After the intervention, post test results revealed that 74% of the women were high in decision making skills and remaining 26% were at average level. Interestingly, none of the respondents had low level of life skills. Thus, intervention found to be effective among women respondents to develop and enhance their empowerment status through decision-making skills.

Scale sensitivity of the Gill circulation, Part II: Off-equatorial case

2021 ◽  
Author(s):  
Gilles Bellon ◽  
Beatriz Reboredo
Keyword(s):  
Diabatic Heating ◽  
Dynamical Response ◽  
Plane Case ◽  
Horizontal Scale ◽  
Overturning Circulation ◽  
Low Level ◽  
Heating Source ◽  
Horizontal Extent ◽  
Westerly Jet ◽  
Tropospheric Heating

Abstract We investigate the steady dynamical response of the atmosphere on the equatorial β-plane to a steady, localized, mid-tropospheric heating source. Following Part I which investigates the case of an equatorial diabatic heating, we explore the sensitivity of the Gill circulation to the latitudinal location of the heating, together with the sensitivity to its horizontal scale. Again, we focus on characteristics of the response which would be particularly important if the circulation interacted with the hydrologic and energy cycles: overturning circulation and low-level wind. In the off-equatorial case, the intensity of the overturning circulation has the same limit as in the equatorial case for small horizontal extent of the diabatic heating, which is also the limit in the f-plane case. The decrease in this intensity with increasing horizontal scale of the diabatic heating is slightly faster in the off-equatorial case than in the equatorial case, which is due to the increase of rotational winds at the expense of divergent winds. The low-level westerly jet is more intense than in the equatorial case, with larger maximum wind and eastward mass transport that tend to infinity for small horizontal extent of the diabatic heating. In terms of spatial characteristics, this jet has a similar latitudinal extent as in the equatorial case but, unlike in the equatorial case, it extends further equatorward than poleward of the diabatic-heating center. It also extends further eastward than in the equatorial case.

The impact of London on a low-level jet

2021 ◽  
Author(s):  
Aristofanis Tsiringakis ◽  
Natalie Theeuwes ◽  
Janet Barlow ◽  
Gert-Jan Steeneveld
Keyword(s):  
Urban Area ◽  
Prediction Models ◽  
Weather Prediction ◽  
Vertical Mixing ◽  
Forecasting Model ◽  
Low Level ◽  
Low Level Jet ◽  
The Difference ◽  
The Impact ◽  
Numerical Weather Prediction Models

<p>The low-level jet (LLJ) is an important phenomenon that can affect (and is affected by) the turbulence in the nocturnal urban boundary layer (UBL). We investigate the interaction of a regional LLJ with the UBL during a 2-day period over London. Observations from two Doppler Lidars and two numerical weather prediction models (Weather Research & Forecasting model and UKV Met Office Unified Model) are used to compared the LLJ characteristics (height, speed and fall-off) between a urban (London) and a rural (Chilbolton) site. We find that LLJs are elevated (70m) over London, due to the deeper UBL, an effect of the increased vertical mixing over the urban area and the difference in the topography between the two sites. Wind speed and fall-off are slightly reduced with respect to the rural LLJ. The effects of the urban area and the surrounding topography on the LLJ characteristics over London are isolated through idealized sensitivity experiments. We find that topography strongly affects the LLJ characteristics (height, falloff, and speed), but there is still a substantial urban influence.</p>

THE LEED-COMMERCIAL INTERIORS (V4) PROJECTS IN CALIFORNIA

2021 ◽  
Vol 16 (3) ◽  
pp. 57-72
Author(s):  
Svetlana Pushkar
Keyword(s):  
Green Building ◽  
Nonparametric Tests ◽  
Indoor Environmental Quality ◽  
Positive Correlation ◽  
Low Level ◽  
Impact Reduction ◽  
Environmental Product Declarations ◽  
The Difference ◽  
High Level ◽  
Building Standards

ABSTRACT This study analyzed the Leadership in Energy and Environmental Design for Commercial Interior Certified, Silver, and Gold projects version 4.0 (LEED-CIv4) in California for the period 2015‒2020. Nonparametric tests were used to assess category and credit achievement, i.e., the difference between possible and achieved points and the correlation between associated credits. The results show that most of the credits in the location and transportation category and the indoor environmental quality categories had a high level of achievement, a few credits in the energy and atmosphere and materials and resources categories had a high level of achievement, and all of the credits in the water efficiency category had a low level of achievement. Some associated credits, such as surrounding density and quality transit, had a high level of achievement and a positive correlation, whereas other associated credits, such as life-cycle impact reduction and environmental product declarations, had a low level of achievement and a positive correlation. If LEED-CIv4 credits meet the requirements of the California Green Building Standards Code 2016 (CGBSC 2016), then these credits typically have a medium/high level of achievement. If LEED-CIv4 credits exceed the requirements of CGBSC 2016, then these credits have a low level of achievement. Therefore, to improve the next version of LEED-CI, it is necessary to improve the local green codes.

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