scholarly journals How the growth of ice depends on the fluid dynamics underneath

2021 ◽  
Vol 118 (10) ◽  
pp. e2012870118
Author(s):  
Ziqi Wang ◽  
Enrico Calzavarini ◽  
Chao Sun ◽  
Federico Toschi
Keyword(s):  
Temporal Evolution ◽  
Global Climate ◽  
Melting Process ◽  
Complex Nature ◽  
Convective Flows ◽  
Qualitative And Quantitative ◽  
Density Anomaly ◽  
Water Layers ◽  
Current Parameter ◽  
Different Levels

Convective flows coupled with solidification or melting in water bodies play a major role in shaping geophysical landscapes. Particularly in relation to the global climate warming scenario, it is essential to be able to accurately quantify how water-body environments dynamically interplay with ice formation or melting process. Previous studies have revealed the complex nature of the icing process, but have often ignored one of the most remarkable particularities of water, its density anomaly, and the induced stratification layers interacting and coupling in a complex way in the presence of turbulence. By combining experiments, numerical simulations, and theoretical modeling, we investigate solidification of freshwater, properly considering phase transition, water density anomaly, and real physical properties of ice and water phases, which we show to be essential for correctly predicting the different qualitative and quantitative behaviors. We identify, with increasing thermal driving, four distinct flow-dynamics regimes, where different levels of coupling among ice front and stably and unstably stratified water layers occur. Despite the complex interaction between the ice front and fluid motions, remarkably, the average ice thickness and growth rate can be well captured with the theoretical model. It is revealed that the thermal driving has major effects on the temporal evolution of the global icing process, which can vary from a few days to a few hours in the current parameter regime. Our model can be applied to general situations where the icing dynamics occur under different thermal and geometrical conditions.

Formation of work models ormation of work models of nursing staff of different levels

2020 ◽  
pp. 39-47
Author(s):  
Irina Muntyan
Keyword(s):  
Nursing Staff ◽  
Nursing Personnel ◽  
Methodological Basis ◽  
Qualitative And Quantitative ◽  
Quantitative Characteristics ◽  
Work Model ◽  
Different Levels ◽  
Qualitative And Quantitative Characteristics

The work model of a nurse includes 14 elements representing the qualitative and quantitative characteristics of the work. The analysis of these elements allowed us to form and offer work models for senior and rankand-file nurses. These models ensure selection, evaluation and placement of nursing personnel on a uniform methodological basis.

scholarly journals Emerging Mosquito-Borne Threats and the Response from European and Eastern Mediterranean Countries

2018 ◽  
Vol 15 (12) ◽  
pp. 2775 ◽  
Author(s):  
Nicholas Johnson ◽  
Mar Fernández de Marco ◽  
Armando Giovannini ◽  
Carla Ippoliti ◽  
Maria Danzetta ◽  
...  
Keyword(s):  
At Risk ◽  
Eastern Mediterranean ◽  
Global Climate ◽  
Detection Methods ◽  
Human Populations ◽  
Tropical Regions ◽  
Mediterranean Countries ◽  
Wildlife Migration ◽  
Different Levels ◽  
Autochthonous Transmission

Mosquito-borne viruses are the cause of some of the greatest burdens to human health worldwide, particularly in tropical regions where both human populations and mosquito numbers are abundant. Due to a combination of anthropogenic change, including the effects on global climate and wildlife migration there is strong evidence that temperate regions are undergoing repeated introduction of mosquito-borne viruses and the re-emergence of viruses that previously were not detected by surveillance. In Europe, the repeated introductions of West Nile and Usutu viruses have been associated with bird migration from Africa, whereas the autochthonous transmission of chikungunya and dengue viruses has been driven by a combination of invasive mosquitoes and rapid transcontinental travel by infected humans. In addition to an increasing number of humans at risk, livestock and wildlife, are also at risk of infection and disease. This in turn can affect international trade and species diversity, respectively. Addressing these challenges requires a range of responses both at national and international level. Increasing the understanding of mosquito-borne transmission of viruses and the development of rapid detection methods and appropriate therapeutics (vaccines / antivirals) all form part of this response. The aim of this review is to consider the range of mosquito-borne viruses that threaten public health in Europe and the eastern Mediterranean, and the national response of a number of countries facing different levels of threat.

New Hybrid Discrete PSO for Solving Non Convex Trim Loss Problem

2012 ◽  
Vol 3 (2) ◽  
pp. 19-41 ◽  
Author(s):  
Kusum Deep ◽  
Pinkey Chauhan ◽  
Millie Pant
Keyword(s):  
Optimal Solution ◽  
Complex Nature ◽  
Sigmoid Function ◽  
Loss Minimization ◽  
Physical Constraints ◽  
Trim Loss ◽  
Discrete Pso ◽  
Global Optimal ◽  
Power Mutation ◽  
Different Levels

Trim loss minimization is the most common problem that arises during the cutting process, when products with variable width or length are to be produced in bulk to satisfy customer demands from limited available/stocked materials. The aim is to minimize inevitable waste material. Under various environmental and physical constraints, the trim loss problem is highly constrained, non convex, nonlinear, and with integer restriction on all variables. Due to the highly complex nature of trim loss problem, it is not easy for manufacturers to select an appropriate method that provides a global optimal solution, satisfying all restrictions. This paper proposes a discrete variant of PSO, which embeds a mutation operator, namely power mutation during the position update stage. The proposed variant is named as Hybrid Discrete PSO (HDPSO). Binary variables in HDPSO are generated using sigmoid function with its domain derived from position update equation. Four examples with different levels of complexity are solved and results are compared with two recently developed GA and PSO variants. The computational studies indicate the competitiveness of proposed variant over other considered methods.

scholarly journals Fossil crocodilian distributions, Upper Cretaceous to present: implications for paleoclimate

1992 ◽  
Vol 6 ◽  
pp. 198-198
Author(s):  
Paul Markwick
Keyword(s):  
Late Cretaceous ◽  
Middle Eocene ◽  
Global Climate ◽  
A Priori ◽  
Tropical Regions ◽  
Cooling Trend ◽  
Geologic Record ◽  
Continental Interior ◽  
Different Levels ◽  
Limited Scope

The present day distribution of crocodilians appears to be climatically controlled, at least in part, with the group restricted to tropical through sub-tropical regions. Studies have shown that although crocodiles may be able to withstand sub-zero temperatures they can do so for only limited periods. By analogy the presence of fossil crocodilians in the geologic record has been interpretated as indicating warmth. However previous studies have generally been of limited scope. This study uses global paleodistributions of the crocodilians to map gross global climate for the last 100 million years.A comprehensive database of published occurrences of fossil crocodilians from the late Cretaceous to the Present has been constructed. Taphonomic and collection biases have been addressed using ‘control groups', these are respectively the Testudines and the vertebrates in general. Problems of taxonomic inconsistency have been dealt with by ‘accepting’ a standard published taxonomic scheme (Carroll, 1988). Geographic and temporal uncertainties and imprecisions are coded on the database to facilitate sorting; this allows the analyses to be run at different levels of precision and provides an opportunity to understand the way biogeographic and hence paleoclimatic interpretations may be influenced by both the nature of the geologic record itself and by a priori decisions made by the worker. The database also includes lithologic, stratigraphic and environmental information on some 3300 localities and includes specimen information for the taxa entered (>14000 separate entries assembled from 1000 references).Preliminary analyses of paleolatitudinally reconstructed localities reveals the following trends: an overall equatorward movement of the poleward limit of the crocodiles from the late Cretaceous to the present; this is punctuated by an abrupt equatorward excursion of almost 10° during the Oligocene and another of similar magnitude at the end of the Miocene, with an apparent Miocene ‘recovery’ in between (this trend is shown most clearly by the families Alligatoridae and Crocodylidae). At the suborder level the Mesosuchians (excluding the Sebecidae) show a distinct equatorial shift from the Campanian through to the middle Eocene when they disappear; inclusion of the Sebecidae in the Mesosuchia gives rise to a sudden poleward expansion in the middle Eocene of some 20° paleolatitude. Map reconstructions, especially for North America, reveal an eastward shift of crocodilian localities as the Tertiary progresses, perhaps due in part to a taphonomic artifact, viz., the migration of the locus of sedimentation. With the late Miocene the crocodilians disappeared completely from the continental interior record, a transition which seems tied to increased aridity (as indicated by the development of caliches in many areas) and increased seasonality of temperature. This pattern is also seen in the southern ‘U.S.S.R’.The distributions of the Crocodylia through time therefore reflect and support established views concerning late Cretaceous through Tertiary climate with a general cooling trend from the late Cretaceous to the present punctuated by abrupt coolings in the Oligocene and around the Miocene-Pliocene boundary.

“Hätte, wäre, wenn…”

2015 ◽  
Vol 1 (1) ◽  
pp. 25-57 ◽  
Author(s):  
Ursula Maden-Weinberger
Keyword(s):  
Second Language Acquisition ◽  
Language Acquisition ◽  
Native Speaker ◽  
Linguistic Knowledge ◽  
Complex Nature ◽  
Human Beings ◽  
Learner Corpus ◽  
Subjunctive Mood ◽  
Cognitive Theories ◽  
Different Levels

The German subjunctive mood (‘Konjunktiv’) is a grammatical feature that attests to the freedom of human beings to step out of the boundaries of their immediate situation and explore new possibilities in hypothetical scenarios. It therefore plays a pivotal role in advanced learner argumentative writing, but due to its highly complex nature regarding both form and usage, the ‘Konjunktiv’ challenges learners on virtually all levels of linguistic knowledge. This paper presents the first learner corpus-based study of this phenomenon with a two-pronged Contrastive Interlanguage Analysis approach: comparing learner data to native-speaker data and learner data at different levels of proficiency using the Corpus of Learner German (CLEG). The investigation seeks to explain the detected patterns of over-, under- and misuse and developmental paths by drawing on cognitive theories of second language acquisition.

CONSTRUCTION OF NEGATIONS IN THE CONTEXT OF CRITICAL THINKING FOR PRIMARY SCHOOL

2018 ◽  
Vol 2 ◽  
pp. 454-463
Author(s):  
Anita Sondore ◽  
Elfrīda Krastiņa ◽  
Pēteris Daugulis ◽  
Elga Drelinga
Keyword(s):  
Critical Thinking ◽  
Primary School ◽  
Qualitative And Quantitative Analysis ◽  
Qualitative And Quantitative ◽  
Correct Usage ◽  
Study Results ◽  
Study Programs ◽  
Study Process ◽  
Primary School Pupils ◽  
Different Levels

In the modern study process it is important to teach pupils critical thinking and involvement in decision making. Formulation of negations and construction of counterexamples is one of the ingredients of critical thinking which are stressed in the new project of the mathematical standard for primary school „Skola 2030” in Latvia. The goal of this study is to analyze experience and skills of primary school pupils and students of teacher study programs, which are related to the ability to formulate negations and counterexamples. A qualitative and quantitative analysis of questionaire answers given by pupils and future teachers is performed in this study. Results of this study show that pupils make mistakes constructing negations and counterexamples. Teachers also have problems constructing correct assertions. These observations should stimulate universities to pay attention to teacher preparation in this sense. Teachers should teach correct usage of the negation operation at different levels of difficulty and correct construction of counterexamples.

scholarly journals Impact of Opened, Non Opened Pollination and Nitrogen Fertilizer on Sesame Production in the Reclaimed Lands, Ismailia Governorate, Egypt

2013 ◽  
Vol 46 (3) ◽  
pp. 57-68
Author(s):  
A.E.H. Blal ◽  
S.M. Kamel ◽  
H.M. Mahfouz ◽  
M. Said
Keyword(s):  
Nitrogen Fertilizer ◽  
Sandy Soils ◽  
Open Pollination ◽  
Insect Pollination ◽  
Qualitative And Quantitative ◽  
Growing Seasons ◽  
Pass Through ◽  
Quantitative Indicators ◽  
The Impact ◽  
Different Levels

Abstract The research was conducted at the Agriculture Research Farm, Faculty of Agriculture, University of Suez Canal, during the sesame growing seasons of 2011 and 2012. For studying the impact of insect pollination and nitrogen fertilization on sesame production, the experiment was divided to 13 treatments of open pollination and non open pollination, with three different levels of ammonium nitrate (NH4NO3) and one level of seryalin as biofertilizer. Non opened pollination treatments were covered before the start of flowering period with a perforated net bag, to allow the air to pass through and to prevent insects from approaching the plants. Quantitative and qualitative indicators, were measured as follows: rate of capsule per plant, capsule weight, rate of seeds in each capsule, weight of 1000 seeds, germination (%), seedlings vigour and oil content (%). Results clearly demonstrate that qualitative and quantitative indicators of sesame crop was significantly increased with opened pollination and with the increase of nitrogen fertilizer level up to 40 kg N/feedan-1 plus or minus seryalin, in reclaimed sandy soils, in Ismailia, Egypt.

scholarly journals Climate Change And Migration: Law and Policy Perspectives in Bangladesh

2014 ◽  
Vol 2 (1) ◽  
pp. 35-53 ◽  
Author(s):  
Mostafa Mahmud NASER
Keyword(s):  
Climate Change ◽  
Global Climate ◽  
Humanitarian Assistance ◽  
Complex Nature ◽  
Adaptation To Climate Change ◽  
Full Spectrum ◽  
Road Map ◽  
Future Challenges ◽  
Straightforward Solution ◽  
And Migration

AbstractGlobal climate change and consequent potential migration pose a number of challenges and are becoming increasingly important policy issues for Bangladesh. Therefore, policy responses need to deal with diverse issues, including sustainable development (SD), adaptation to climate change, and humanitarian assistance, to address the future challenges posed by climate change and consequent human displacement. There is no simple and straightforward solution to the challenges posed by climate-induced migration, and a “one-size-fits-all” approach will not effectively resolve the complex nature, and patterns, of population displacement. Rather than any single approach, a multifarious, comprehensive, proactive, and coherent policy approach is imperative for managing climate-induced migration in an orderly and humane manner. Based on the available data regarding the environment, climate change, and migration, this paper suggests a range of policy tools and approaches. It also sets out a road map showing how policy interventions could contribute to better integrating the full spectrum of migration issues and concerns into an overall environmental and developmental policy, and vice versa, within Bangladesh.

Supporting the Management of Ecosystem Services in Protected Areas: Trade-Offs Between Effort and Accuracy in Evaluation

2017 ◽  
Vol 19 (02) ◽  
pp. 1750007 ◽  
Author(s):  
Uta Schirpke ◽  
Rocco Scolozzi ◽  
Benedetta Concetti ◽  
Bruna Comini ◽  
Ulrike Tappeiner
Keyword(s):  
Ecosystem Services ◽  
Protected Areas ◽  
Spatial Scale ◽  
Well Being ◽  
Natura 2000 ◽  
Qualitative And Quantitative ◽  
Monetary Valuation ◽  
Trade Offs ◽  
Multiple Levels ◽  
Different Levels

Integrating ecosystem services (ES) into the management of protected areas, such as European Natura 2000 sites, can improve biodiversity conservation and human well-being; yet, the assessment and application of ES remains challenging. In this study, we propose a roadmap to guide managers in the assessment of ES at multiple levels, including a non-monetary valuation in qualitative and quantitative terms, as well as a monetary valuation, and suggesting the appropriate applications related to ES mapping, communication and planning. The roadmap proceeds through four steps and along a gradient of accuracy and effort required in the assessment methods, with different levels of spatial scale, to effectively support managers. Together with the description of the roadmap, this paper provides insights from its application to terrestrial Natura 2000 sites in Italy.

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