scholarly journals HYDRODYNAMIC MODELLING IN INSHORE REEF AREA WITHIN KUANTAN COASTAL REGION

2020 ◽  
Vol 4 (1) ◽  
pp. 01-07
Author(s):  
Muhammad Faiz Mohd Hanapiah ◽  
Shahbudin Saad ◽  
Zuhairi Ahmad
Keyword(s):  
Model Simulation ◽  
Coastal Region ◽  
Flow Speed ◽  
Current Speed ◽  
Benthic Organism ◽  
Reef Area ◽  
Inshore Reef ◽  
Highly Correlated ◽  
The Impact ◽  
Current Circulation

Current circulation provides major transport mechanism especially for benthic organism in the ocean. The present study described current circulation in inshore reef area within Kuantan coastal region by applying a numerical modelling of MIKE 21 Flow Model FM software. Model simulation produced good outcomes when compared with field data measurement with root mean square error (RMSE) for surface elevation, current speed and direction were below 20. Results also clearly indicated that current speed in inshore reef area was highly correlated with local tidal pattern in which higher flow speed were observed during high tides compared to low tide. Contrary to previous belief, our results clearly show the prevalence of tidal forcing in shaping current flow pattern in the study area since the impact of wind forcing was minimal during different monsoon seasons. This study gave new insight into how local tidal properties can regulate hydrodynamic pattern especially in fine-scale inshore reef area.

Response of Poinsettia Growth and Development to Ratio of Radiant to Thermal Energy

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 508e-508
Author(s):  
Bin Liu ◽  
Royal D. Heins
Keyword(s):  
Plant Growth ◽  
Thermal Energy ◽  
Growth And Development ◽  
Model Simulation ◽  
Interactive Effect ◽  
Dry Weight ◽  
Plant Spacing ◽  
Plant Growth And Development ◽  
Daily Light Integral ◽  
Highly Correlated

A concept of ratio of radiant to thermal energy (RRT) has been developed to deal with the interactive effect of light and temperature on plant growth and development. This study further confirms that RRT is a useful parameter for plant growth, development, and quality control. Based on greenhouse experiments conducted with 27 treatment combinations of temperature, light, and plant spacing, a model for poinsettia plant growth and development was constructed using the computer program STELLA II. Results from the model simulation with different levels of daily light integral, temperature, and plant spacing showed that the RRT significantly affects leaf unfolding rate when RRT is lower than 0.025 mol/degree-day per plant. Plant dry weight is highly correlated with RRT; it increases linearly as RRT increases.

scholarly journals The Influence of Trading Locations on Equity Returns

2016 ◽  
Vol 12 (12) ◽  
pp. 188
Author(s):  
Nguyen N.T. Vo
Keyword(s):  
Risk Premium ◽  
Stock Price ◽  
Listed Companies ◽  
Equity Returns ◽  
Stock Exchanges ◽  
Home Market ◽  
Trade Effect ◽  
Market Index ◽  
Highly Correlated ◽  
The Impact

This paper evaluates the impact of trading locations on equity returns by examining the stock price behaviour of three Anglo-Dutch dual-listed companies which result from mergers where two corporations agree to function as a single operating business, but maintain separate identities. The shares of these stocks are traded not only in their home market but also on several US stock exchanges in the form of American Depository Receipts. Regressing the return differentials on these dual-listed and cross-listed stocks on the relative market index returns and currency changes provides evidence of an apparent violation of the Law of One Price. The regression results show that the return on each part of dual-listed companies is highly correlated with the market on which it is most intensively traded. Similarly, returns on cross-listed stocks have considerably higher co-movement with US market indices and considerably lower co-movement with home-market indices than their home-market counterparts. Market risk premium is not a significant explanatory variable of the location of trade effect.

Investigation on penetration model of shaped charge jet in water

2016 ◽  
Vol 30 (02) ◽  
pp. 1550268 ◽  
Author(s):  
Jinwei Shi ◽  
Xingbai Luo ◽  
Jinming Li ◽  
Jianwei Jiang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Model ◽  
Model Simulation ◽  
Theoretical Models ◽  
Theoretical Research ◽  
Water Medium ◽  
Simulation Results ◽  
Jet Penetration ◽  
The Impact ◽  
Penetration Velocity

To analyze the process of jet penetration in water medium quantitatively, the properties of jet penetration spaced target with water interlayer were studied through test and numerical simulation. Two theoretical models of jet penetration in water were proposed. The theoretical model 1 was established considering the impact of the shock wave, combined with the shock equation Rankine–Hugoniot and the virtual origin calculation method. The theoretical model 2 was obtained by fitting theoretical analysis and numerical simulation results. The effectiveness and universality of the two theoretical models were compared through the numerical simulation results. Both the models can reflect the relationship between the penetration velocity and the penetration distance in water well, and both the deviation and stability of theoretical model 1 are better than 2, the lower penetration velocity, and the larger deviation of the theoretical model 2. Therefore, the theoretical model 1 can reflect the properties of jet penetration in water effectively, and provide the reference of model simulation and theoretical research.

Examining Terrain Effects on an Upstate New York Tornado Event Utilizing a High-Resolution Model Simulation

2021 ◽  
Author(s):  
Luke J. LeBel ◽  
Brian H. Tang ◽  
Ross A. Lazear
Keyword(s):  
New York ◽  
High Resolution ◽  
Wind Shear ◽  
Model Simulation ◽  
Wrf Model ◽  
Severe Weather ◽  
Streamwise Vorticity ◽  
Low Level ◽  
Severe Convection ◽  
The Impact

AbstractThe complex terrain at the intersection of the Mohawk and Hudson valleys of New York has an impact on the development and evolution of severe convection in the region. Specifically, previous research has concluded that terrain-channeled flow in the Mohawk and Hudson valleys likely contributes to increased low-level wind shear and instability in the valleys during severe weather events such as the historic 31 May 1998 event that produced a strong (F3) tornado in Mechanicville, New York.The goal of this study is to further examine the impact of terrain channeling on severe convection by analyzing a high-resolution WRF model simulation of the 31 May 1998 event. Results from the simulation suggest that terrain-channeled flow resulted in the localized formation of an enhanced low-level moisture gradient, resembling a dryline, at the intersection of the Mohawk and Hudson valleys. East of this boundary, the environment was characterized by stronger low-level wind shear and greater low-level moisture and instability, increasing tornadogenesis potential. A simulated supercell intensified after crossing the boundary, as the larger instability and streamwise vorticity of the low-level inflow was ingested into the supercell updraft. These results suggest that terrain can have a key role in producing mesoscale inhomogeneities that impact the evolution of severe convection. Recognition of these terrain-induced boundaries may help in anticipating where the risk of severe weather may be locally enhanced.

scholarly journals Exploiting correlated molecular-dynamics networks to counteract enzyme activity–stability trade-off

2018 ◽  
Vol 115 (52) ◽  
pp. E12192-E12200 ◽  
Author(s):  
Haoran Yu ◽  
Paul A. Dalby
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Active Site ◽  
Dynamic Networks ◽  
Aromatic Aldehydes ◽  
Active Site Residues ◽  
Trade Off ◽  
Highly Correlated ◽  
Dynamics Simulations ◽  
The Impact

The directed evolution of enzymes for improved activity or substrate specificity commonly leads to a trade-off in stability. We have identified an activity–stability trade-off and a loss in unfolding cooperativity for a variant (3M) of Escherichia coli transketolase (TK) engineered to accept aromatic substrates. Molecular dynamics simulations of 3M revealed increased flexibility in several interconnected active-site regions that also form part of the dimer interface. Mutating the newly flexible active-site residues to regain stability risked losing the new activity. We hypothesized that stabilizing mutations could be targeted to residues outside of the active site, whose dynamics were correlated with the newly flexible active-site residues. We previously stabilized WT TK by targeting mutations to highly flexible regions. These regions were much less flexible in 3M and would not have been selected a priori as targets using the same strategy based on flexibility alone. However, their dynamics were highly correlated with the newly flexible active-site regions of 3M. Introducing the previous mutations into 3M reestablished the WT level of stability and unfolding cooperativity, giving a 10.8-fold improved half-life at 55 °C, and increased midpoint and aggregation onset temperatures by 3 °C and 4.3 °C, respectively. Even the activity toward aromatic aldehydes increased up to threefold. Molecular dynamics simulations confirmed that the mutations rigidified the active-site via the correlated network. This work provides insights into the impact of rigidifying mutations within highly correlated dynamic networks that could also be useful for developing improved computational protein engineering strategies.

Fractality of Simulated Fracture

2009 ◽  
Vol 409 ◽  
pp. 154-160 ◽  
Author(s):  
Petr Frantík ◽  
Zbyněk Keršner ◽  
Václav Veselý ◽  
Ladislav Řoutil
Keyword(s):  
Numerical Model ◽  
Elastic Plate ◽  
Model Simulation ◽  
Element Model ◽  
The Other ◽  
Particle Model ◽  
Discrete Element Model ◽  
Fractal Nature ◽  
Discrete Elements ◽  
The Impact

The paper is focussed on numerical simulations of the fracture of a quasi-brittle specimen due to its impact onto a fixed rigid elastic plate. The failure of the specimen after the impact is modelled in two ways based on the physical discretization of continuum: via physical discrete elements and pseudo-particles. Advantages and drawbacks of both used methods are discussed. The size distribution of the fragments of the broken specimen resulting from physical discrete element model simulation follows a power law, which indicates the ability of the numerical model to identify the fractal nature of the fracture. The pseudo-particle model, on the other side, can successfully predict the kinematics of the fragments of the specimen under impact failure.

scholarly journals Exploring farmers’ perception on climate-induced events and adaptation practices to protect crop production and livestock farming in Haor area of northeastern Bangladesh

2021 ◽  
Author(s):  
Tasneem Chowdhury Fahim ◽  
Bivuti Bhushan Sikder
Keyword(s):  
Climate Change ◽  
Crop Production ◽  
Coastal Region ◽  
Climate Extremes ◽  
Livestock Farming ◽  
Chi Square ◽  
Study Results ◽  
Tools And Techniques ◽  
Adaptation Practices ◽  
The Impact

Abstract Bangladesh is confronting terrible impacts of climate change on agriculture across the country, especially in the low-lying area like- Haor, coastal region, and islands. This behavioral study (N = 320) examines the perception and knowledge of farmers on climate-induced events and experiences, and explores the adaptation practices they adopt to protect crop production and livestock farming from the impact of climate change in the Northeastern Haor area of the country. Using triangulation method, it is detected that farmers of the study area have erroneous idea on climate change and the causes of frequent climate extremes. Study results show that respondents’ perception and experiences on climate-induced event are verified positively with the historical trend and time-series analysis of climate indicators as well as with the findings of researchers using PRA tools and techniques. This study explores the traditional and systematic adaptation approaches of farmers which are practiced in individual or community level. The rationale of each of the approach from respondents’ side is also analyzed in the study. It is statistically tested using chi-square that some of the scientific and systematic adaptation options for crop production is predominantly influenced by the educational qualifications of the respondents. The study reveals that lack of proper information prevents subsistence farmers to find the most effective adaptation pathways.

scholarly journals The Impact of Criteria-based and Data-driven Sampling Approaches on the Heterogeneity and Interpretability of Posttraumatic Stress Symptom Networks

2020 ◽  
Author(s):  
Santiago Papini ◽  
Mikael Rubin ◽  
Michael J Telch ◽  
Jasper A. J. Smits
Keyword(s):  
Data Driven ◽  
Network Heterogeneity ◽  
Psychopathological Symptom ◽  
Highly Correlated ◽  
And Cluster Analysis ◽  
Sensitivity Specificity ◽  
Future Work ◽  
The Impact ◽  
Sample Heterogeneity ◽  
Source Of Error

Background. The application of psychopathological symptom networks requires reconciliation of the observed cross-sample heterogeneity. We leveraged the largest sample to be used in a PTSD network analysis (N = 28,594) to examine the impact of criteria-based and data-driven sampling approaches on the heterogeneity and interpretability of networks.Methods. Severity and diagnostic criteria identified four overlapping subsamples and cluster analysis identified three distinct data-derived profiles. Networks estimated on each subsample were compared to a respective benchmark network at the symptom-relation level by calculating sensitivity, specificity, correlation, and density of the edges. Negative edges were assessed for Berkson’s bias, a source of error that can be induced by threshold samples on severity.Results. Criteria-based networks showed reduced sensitivity, specificity, and density but edges remained highly correlated and a meaningfully higher proportion of negative edges was not observed relative to the benchmark network of all cases. Among the data-derived profile networks, the Low Severity network had the highest proportion of negative edges not present in the benchmark network of symptomatic cases. The High Severity profile also showed a higher proportion of negative edges, whereas the Medium Severity profile did not. Conclusion. Although networks showed differences, Berkson’s bias did not appear to be a meaningful source of systematic error. These results can guide expectations about the generalizability of symptom networks across samples that vary in their ranges of severity. Future work should continue to explore whether network heterogeneity is reflective of meaningful and interpretable differences in the symptom relations from which they are composed.

scholarly journals Regional characteristics of spring Asian dust and its impact on aerosol chemistry over northern China

2006 ◽  
Vol 6 (6) ◽  
pp. 12825-12864 ◽  
Author(s):  
Y. L. Sun ◽  
G. S. Zhuang ◽  
Z. F. Wang ◽  
Y. Wang ◽  
W. J. Zhang ◽  
...  
Keyword(s):  
Dust Storm ◽  
Fine Particles ◽  
Coastal Region ◽  
Northern China ◽  
Asian Dust ◽  
Aerosol Chemistry ◽  
Transport Pathway ◽  
Regional Characteristics ◽  
Source Regions ◽  
The Impact

Abstract. TSP and PM2.5 aerosol samples were synchronously collected at six sites along the transport pathway of dust storm from desert regions to coastal areas in the spring of 2004. The aerosol concentration and composition were measured to investigate the regional characteristics of spring Asian dust and its impact on aerosol chemistry over northern China. Based on the daily PM10 concentrations in 13 cities, the northern China could be divided into five regions, i.e., Northern Dust Region, Northeastern Dust Region, Western Dust Region, Inland Passing Region, and Coastal Region. Northern Dust Region was characterized by high content of Ca and Northeastern Dust Region was characterized by low one instead. Northeastern Dust Region was a relatively clean area with the lowest concentrations of pollutants and secondary ions among all sites. Inland Passing Region and Coastal Region showed high concentrations of pollutants, of which As and Pb in Inland Passing Region, and Na+, SO42− and NO3− in Coastal Region were the highest, respectively. The impact of dust on air quality was the greatest in the cities near source regions, and this impact decreased in the order of Yulin/Duolun > Beijing > Qingdao/Shanghai as the increase of transport distance. The spring Asian dust was inclined to affect the chemical components in coarse particles near source regions and those in fine particles in the cities far from source regions. Dust storm could mix significant quantities of pollutants on the pathway and carry them to the downwind cities or dilute the pollutants in the cities over northern China. Each dust episode corresponded to a low ratio of NO3−/SO42− with the lowest value appearing after the peak of dust storm. Asian dust played an important role in buffering and neutralizing the acidity of atmosphere in the cities over northern China, which could lead to the pH in the aerosols increase ~1 in spring.

scholarly journals Edaphic characteristics of Austrian pine (Pinus nigra Arn.) forests in the Visegrad area

2016 ◽  
Vol 68 (2) ◽  
pp. 355-362
Author(s):  
Velibor Blagojevic ◽  
Milan Knezevic ◽  
Olivera Kosanin ◽  
Marijana Kapovic-Solomun ◽  
Radovan Lucic ◽  
...  
Keyword(s):  
Pinus Nigra ◽  
Research Area ◽  
Geological Structure ◽  
Forest Communities ◽  
Production Potential ◽  
High Production ◽  
Highly Correlated ◽  
The Impact ◽  
Important Basis ◽  
Forest Habitats

This paper presents the results of soil research in Austrian pine (Pinus nigra Arn.) forest communities in the Visegrad area, carried out to determine the basic soil characteristics and eco-production potential of forest habitats as an important basis and framework for the successful management of these forests on the principles of sustainable development. Austrian pine forests in this region are an important and ecologically valuable community. The complexity of the geological structure and relief dynamics are dominant environmental factors that condition the expressed variability of soils in the study area. Forest communities of Austrian pine are formed on the peridotites and serpentinites, eutric ranker (haplic leptosol), eutric cambisol (haplic cambisols) and pseudogley (haplic planosol), dense granular and marl limestones calcomelanosol (mollic leptosol), rendzina (rendzic leptosol) and calcocambisol (leptic cambisol). The productivity of these soils is highly correlated with depth and texture composition, and the impact of these factors is linked with soil type, climate and other site conditions. In the research area, soil types with low production potential such as rankers, rendzinas, limestone and dolomite calcomelanosol are dominant. Deeper variants of eutric cambisol, pseudogley and calcocambisol can be classified as soils with moderate to high production potential.

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