R.A. Daly’s early model of seafloor generation 40 years before the Vine–Matthews hypothesis: an outstanding theoretical achievement inspired by field work on St. Helena in 1921–1922

2015 ◽  
Vol 52 (10) ◽  
pp. 893-902 ◽  
Author(s):  
Dominik Letsch
Keyword(s):  
Earth Sciences ◽  
Oceanic Crust ◽  
Plate Tectonics ◽  
Large Scale ◽  
Field Work ◽  
Scientific Models ◽  
Small Scale ◽  
Early Model ◽  
Definition Of ◽  
St Helena

Large-scale lateral mobility of the Earth’s lithosphere (mobilism) was a hotly debated issue in Earth Sciences during some two decades following publication of Wegener’s (1912) theory of continental displacement. The final acceptance of lithospheric mobility was brought about with the plate tectonics revolution during the late 1960s. Support for mobilism was rather popular in certain European countries during the 1920s, whereas the reactions in North America were mostly hostile. One of the very few influential mobilists in the New World was Reginald Aldworth Daly of Harvard University. The present paper discusses his model of continental displacement which is very remarkable in many aspects. We focus on the hitherto neglected fact that Daly proposed in the mid-1920s a mechanism to create oceanic crust which would have been totally consistent with the Vine–Matthews hypothesis of seafloor generation published in 1963. It is furthermore suggested that Daly’s geotectonic proposals were inspired by small-scale analogues of lava flows and multiple dike swarms he observed on Atlantic islands such as St. Helena and Ascension. His model to account for the construction of new oceanic crust is reminiscent of the models of Vine and Moores (1972) and Cann (1970) which eventually led to the “Penrose-definition” of ophiolites in 1972. As these scientists arrived at their conclusions absolutely independently of Daly, this episode is an instructive example of a multiple or repeated discovery in the Earth Sciences which renders it difficult to believe certain theories of science which assume scientific models to depend mostly on social factors.

scholarly journals Geographical and logistical factors of sustainable development of rural tourism in the context of regional economy

2016 ◽  
pp. 9-14
Author(s):  
I. Smyrnov
Keyword(s):  
Sustainable Development ◽  
Large Scale ◽  
Regional Economy ◽  
Local Economy ◽  
Rural Tourism ◽  
Small Scale ◽  
Resource Base ◽  
Tourist Flows ◽  
Definition Of ◽  
The Impact

Rural tourism is now seen as an important direction of development of the regional economy. From the perspective of sustainable development rural tourism affects the economic, social and environmental aspects of the regional and local economy. Rural tourism is closely linked with agrotourism, eco-tourism, natural tourism and so on. Sustainable rural tourism can be realized by applying logistic, geographic and marketing approaches as components of sustainable development strategies. Logistics approach is determined by logistic potential of resource base of rural tourism and appropriate tourist flows regulation. In this context in the article the concept of tourism capacity or capacity of the resource base of rural tourism is used. The problem of the definition of tourism pressure on the resource base of rural tourism, particularly in natural landscapes is disclosed. Unlike environmental and recrealogical sciences, which stop at the capacity definition of the resource base of tourism, tourism logistics compares this figure with the existing tourist flows and accordingly determines the safe way of tourism management to ensure its sustainable nature. It was shown that these strategies boil down to two basic types – the further development of tourism in a particular area or limit such activities to conserve the resource base of tourism. Recreational (travel) load is the indicator that reflects the impact of tourism on the resource base of tourism (especially landscape complex), expressed by the number of tourists or tourists-days per area unit or per tourist site for the certain period of time (day, month, season year). There are actual, allowable (the maximum) and destructive (dangerous) types of travel load. The latter can lead recreational area or resource base of rural tourism to destruction. Thus, depending on the intensity of tourism resource base using in rural tourism it may change – according to tourist consumption. Large number of tourists affects the entire range of recreational destinations and their individual components. The most vulnerable part of the environment in this sense is vegetation, except that significant changes may occur with soil, water bodies, air and so on. The geographic dimension of the problem of rural tourism sustainable development includes the concept of zoning, ie the division of the territory, offering to develop rural tourism in several zones with different modes of travel usage – from a total ban (in protected areas) for complete freedom with transitional stages, involving various limit degrees in the development of rural tourism. Marketing approach reflects the application of the curve R. Butler to the stages of development of rural tourism destinations with the release of such steps as: research, involvement, development, consolidation, stagnation (also called “saturation”), revival or decline. Shown the models that link the stage of resource base tourist development (under “Curve Butler”), strength of tourism consumption the magnitude of such effects (eg weak (disperse) impact in large scale, strong (concentrated) impact in large scale, strong (concentrated) impact in small scale, weak (disperse) impact in small scale), dynamics of tourism development at the territory.

Conclusion

2017 ◽  
Keyword(s):  
National Identity ◽  
Geographical Distribution ◽  
Crucial Role ◽  
Large Scale ◽  
Small Scale ◽  
Modern History ◽  
Late Modernity ◽  
History Of ◽  
Definition Of

This chapter extends the book’s insights about nature, technology, and nation to the larger history of the modern period. While the modern nation loses its grip as a locus of identity and analysis, attempts to understand the operation, disruption, and collapse of continental and global infrastructures continue to mix the natural and the machinic in ways that define them both. Those vulnerabilities emphasize large-scale catastrophe; historiographically, they mask the crucial role of small-scale failures in the experience and culture of late modernity, including its definition of nature. Historical actors turned the uneven geographical distribution of small-scale failures into a marker of distinctive local natures and an element of regional and national identity. Attending to those failures helps not only situate cold-war technologies in the larger modern history of natural and machinic orders; it helps provincialize the superpowers by casting problematic “other” natures as central and primary.

scholarly journals Balanced reconnection intervals: four case studies

2008 ◽  
Vol 26 (12) ◽  
pp. 3897-3912 ◽  
Author(s):  
A. D. DeJong ◽  
A. J. Ridley ◽  
C. R. Clauer
Keyword(s):  
Case Studies ◽  
Large Scale ◽  
The Other ◽  
Small Scale ◽  
Polar Cap ◽  
Reconnection Rate ◽  
Magnetospheric Convection ◽  
The Third ◽  
New Name ◽  
Definition Of

Abstract. During steady magnetospheric convection (SMC) events the magnetosphere is active, yet there are no data signatures of a large scale reconfiguration, such as a substorm. While this definition has been used for years it fails to elucidate the true physics that is occurring within the magnetosphere, which is that the dayside merging rate and the nightside reconnection rate balance. Thus, it is suggested that these events be renamed Balanced Reconnection Intervals (BRIs). This paper investigates four diverse BRI events that support the idea that new name for these events is needed. The 3–4 February 1998 event falls well into the classic definition of an SMC set forth by Sergeev et al. (1996), while the other challenge some previous notions about SMCs. The 15 February 1998 event fails to end with a substorm expansion and concludes as the magnetospheric activity slowly quiets. The third event, 22–23 December 2000, begins with a slow build up of magnetospheric activity, thus there is no initiating substorm expansion. The last event, 17 February 1998, is more active (larger AE, AL and cross polar cap potential) than previously studied SMCs. It also has more small scale activity than the other events studied here.

scholarly journals Significance of the Small and Medium Enterprises (SMEs) Sector in Pakistan and Assessment of its Employment Potential

2000 ◽  
Vol 5 (1) ◽  
pp. 23-59 ◽  
Author(s):  
Shahid Amjad Chaudhry
Keyword(s):  
Health Insurance ◽  
Social Security ◽  
Old Age ◽  
Large Scale ◽  
Small And Medium Enterprises ◽  
Small Scale ◽  
Medium Enterprise ◽  
Employment Potential ◽  
Definition Of ◽  
Medium Enterprises

Definitions and Sources Definitions: In this paper it is proposed to use the definition of selfemployed, small scale (2-9 employees), medium scale (10-99 employees) and large scale (100 employees and above) to discuss the issues relating to the Small and Medium Enterprise (SME) sector in Pakistan. The national pension (regulated through the Employees Old Age Benefit Institution Legislation) and health insurance (The Provincial Social Security Institutions Legislation) is applicable to institutions with 10 or more employees and provides a natural cut off point between the small scale and medium and large scale sectors. The cut off between the medium and large scale at 100 workers is also appropriate.

scholarly journals From Chernozem to Luvisol or from Luvisol to Chernozem? A discussion about the relationships and limits of the two types of soils. A case study of the soil catena of Hrušov, Czechia

Geografie ◽  
2020 ◽  
Vol 125 (4) ◽  
pp. 473-500
Author(s):  
Barbora Strouhalová ◽  
Anne Gebhardt ◽  
Damien Ertlen ◽  
Luděk Šefrna ◽  
Kristýna Flašarová ◽  
...  
Keyword(s):  
Large Scale ◽  
Field Work ◽  
Intensive Agriculture ◽  
Soil Types ◽  
Small Scale ◽  
Soil Micromorphology ◽  
Simultaneous Presence ◽  
Soil Evolution ◽  
Soil Catena

The patchy character of the distribution of Chernozems and Luvisols formed on loess is often observable on the pedological maps, on a large scale, in Czechia. The focus of the paper is to examine the features of the soil catena of Hrušov (Czechia), which is characterized by the simultaneous presence of Chernozem, Luvisol and Luvic Chernozem – without obvious environmental reasons. A catena of only 330 meters is considered a system of transformation between these soils. Along with field work and the pedological analysis, we used the soil micromorphology method to understand the processes of pedogenesis. We concluded that the presence of considerably different soil types on a small scale is due to intensive agriculture. We found that the present Chernozem is formed on the Luvisol by retrograde soil evolution, which included a shift in the vegetation, erosion, and recarbonation. The evolution of Luvisol in the lower part of the catena has been considerably modified.

scholarly journals Crossing Multiple Gray Zones in the Transition from Mesoscale to Microscale Simulation over Complex Terrain

Atmosphere ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 274 ◽  
Author(s):  
Fotini Chow ◽  
Christoph Schär ◽  
Nikolina Ban ◽  
Katherine Lundquist ◽  
Linda Schlemmer ◽  
...  
Keyword(s):  
Complex Terrain ◽  
Large Scale ◽  
Climate Modeling ◽  
Numerical Models ◽  
Weather Prediction ◽  
Regional Climate ◽  
Regional Climate Modeling ◽  
Small Scale ◽  
Gray Zone ◽  
Definition Of

This review paper explores the field of mesoscale to microscale modeling over complex terrain as it traverses multiple so-called gray zones. In an attempt to bridge the gap between previous large-scale and small-scale modeling efforts, atmospheric simulations are being run at an unprecedented range of resolutions. The gray zone is the range of grid resolutions where particular features are neither subgrid nor fully resolved, but rather are partially resolved. The definition of a gray zone depends strongly on the feature being represented and its relationship to the model resolution. This paper explores three gray zones relevant to simulations over complex terrain: turbulence, convection, and topography. Taken together, these may be referred to as the gray continuum. The focus is on horizontal grid resolutions from ∼10 km to ∼10 m. In each case, the challenges are presented together with recent progress in the literature. A common theme is to address cross-scale interaction and scale-awareness in parameterization schemes. How numerical models are designed to cross these gray zones is critical to complex terrain applications in numerical weather prediction, wind resource forecasting, and regional climate modeling, among others.

scholarly journals Spherical convective dynamos in the rapidly rotating asymptotic regime

2017 ◽  
Vol 813 ◽  
pp. 558-593 ◽  
Author(s):  
Julien Aubert ◽  
Thomas Gastine ◽  
Alexandre Fournier
Keyword(s):  
Large Scale ◽  
Scaling Laws ◽  
Numerical Solutions ◽  
Strong Field ◽  
Magnetic Reynolds Number ◽  
Small Scale ◽  
Asymptotic State ◽  
Asymptotic Regime ◽  
Classical Models ◽  
Definition Of

Self-sustained convective dynamos in planetary systems operate in an asymptotic regime of rapid rotation, where a balance is thought to hold between the Coriolis, pressure, buoyancy and Lorentz forces (the MAC balance). Classical numerical solutions have previously been obtained in a regime of moderate rotation where viscous and inertial forces are still significant. We define a uni-dimensional path in parameter space between classical models and asymptotic conditions from the requirements to enforce a MAC balance and to preserve the ratio between the magnetic diffusion and convective overturn times (the magnetic Reynolds number). Direct numerical simulations performed along this path show that the spatial structure of the solution at scales larger than the magnetic dissipation length is largely invariant. This enables the definition of large-eddy simulations resting on the assumption that small-scale details of the hydrodynamic turbulence are irrelevant to the determination of the large-scale asymptotic state. These simulations are shown to be in good agreement with direct simulations in the range where both are feasible, and can be computed for control parameter values far beyond the current state of the art, such as an Ekman number $E=10^{-8}$. We obtain strong-field convective dynamos approaching the MAC balance and a Taylor state to an unprecedented degree of accuracy. The physical connection between classical models and asymptotic conditions is shown to be devoid of abrupt transitions, demonstrating the asymptotic relevance of classical numerical dynamo mechanisms. The fields of the system are confirmed to follow diffusivity-free, power-based scaling laws along the path.

scholarly journals Multicriteria Definition of Small-Scale Biorefineries Based on a Statistical Classification

2021 ◽  
Vol 13 (13) ◽  
pp. 7310
Author(s):  
Aicha Ait Sair ◽  
Kamal Kansou ◽  
Franck Michaud ◽  
Bernard Cathala
Keyword(s):  
Large Scale ◽  
Added Value ◽  
Small Scale ◽  
Processing Capacity ◽  
Trade Offs ◽  
End Products ◽  
Investment Cost ◽  
Consensual Definition ◽  
Definition Of ◽  
Process Complexity

Biorefineries have many possible designs and therefore, present varied benefits in regards to sustainable development. Evaluating these biorefineries is central for the domain, and, as small-scale biorefineries (SSB) are commonly opposed to the large ones, specifying the concept of scale of a biorefinery is essential as well. However, there is no consensual definition of the “scale”, and the meaning of the term changes with the context. This paper presents a methodology to specify the concept of scale by grouping various biorefineries processing lignocellulosic biomass according to factors related to feedstock, process, economy and mobility of the facility, without any predetermined pattern. Data from 15 operational biorefineries are analyzed using a multivariate analysis combined with a hierarchical clustering. The classification obtained categorizes biorefineries into four design classes: smallest, small, hybrid and large scale. Small-scale biorefineries are characterized by a small investment cost (less than 2 M€), a low processing capacity (less than 100 t/day) and a low process complexity, while the end-products’ added value is variable. The mobility of the plants is a sufficient, but not necessary, criterion to have a small-scale biorefinery. Finally, the designs of the investigated biorefineries can be explained by two main trade-offs: one between the mobility and the processing capacity-investment cost, and the other between the process complexity and the added value.

Quasi-experimental research in culture sensitive psychology

2018 ◽  
Vol 24 (3) ◽  
pp. 327-342 ◽  
Author(s):  
Pierre R. Dasen ◽  
Ramesh C. Mishra ◽  
Jürg Wassmann
Keyword(s):  
Large Scale ◽  
Cultural Psychology ◽  
Developmental Psychology ◽  
Field Work ◽  
Cross Cultural ◽  
Small Scale ◽  
Spatial Skills ◽  
Cultural Variables ◽  
Quasi Experimental ◽  
The Many

The research presented in this article follows up on several aspects of Gustav Jahoda’s long and fruitful career: (1) his early fieldwork on cognitive development in Africa, particularly in the area of spatial skills; (2) his interest in cross-cultural psychology as a research method; and (3) his insistence on bringing anthropology and psychology together. The topic of our research is the development of a so-called “geocentric” frame of spatial reference. This is a cognitive style, in which individuals describe and represent small-scale table-top space in terms of large-scale geographic dimensions. We explore the development with age of geocentric language and cognition, and the relationships between the two. We also explore the many environmental and socio-cultural variables that favor the use of this frame. We demonstrate how we untangled several of these variables by using a succession of within-society group comparisons, in several societies where a geocentric frame is in common usage (Bali, Indonesia, India, and Nepal). Our research program unfolds like a detective story, where one finding that is difficult to interpret because of several confounded variables leads to another quasi-experimental group comparison that suggests another hypothesis, which is then tested in a further session of field-work. In each case, we emphasize how important it was to have extensive linguistic and ethnographic knowledge before implementing psychological tests. The research design is not cross-cultural as such (we hardly ever perform comparisons between societies), but culturally sensitive within a series of societies; in other words, as Dasen and Jahoda (1986 , p. 413) defined it, “cross-cultural developmental psychology is not just comparative: essentially it is an outlook that takes culture seriously.”

scholarly journals BERT-PLI: Modeling Paragraph-Level Interactions for Legal Case Retrieval

2020 ◽  
Author(s):  
Yunqiu Shao ◽  
Jiaxin Mao ◽  
Yiqun Liu ◽  
Weizhi Ma ◽  
Ken Satoh ◽  
...  
Keyword(s):  
Large Scale ◽  
Ad Hoc ◽  
Computational Cost ◽  
Small Scale ◽  
Case Retrieval ◽  
Retrieval Task ◽  
Semantic Relationships ◽  
Relevance Judgments ◽  
Legal Case ◽  
Definition Of

Legal case retrieval is a specialized IR task that involves retrieving supporting cases given a query case. Compared with traditional ad-hoc text retrieval, the legal case retrieval task is more challenging since the query case is much longer and more complex than common keyword queries. Besides that, the definition of relevance between a query case and a supporting case is beyond general topical relevance and it is therefore difficult to construct a large-scale case retrieval dataset, especially one with accurate relevance judgments. To address these challenges, we propose BERT-PLI, a novel model that utilizes BERT to capture the semantic relationships at the paragraph-level and then infers the relevance between two cases by aggregating paragraph-level interactions. We fine-tune the BERT model with a relatively small-scale case law entailment dataset to adapt it to the legal scenario and employ a cascade framework to reduce the computational cost. We conduct extensive experiments on the benchmark of the relevant case retrieval task in COLIEE 2019. Experimental results demonstrate that our proposed method outperforms existing solutions.

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