Computation in Focused Intuitionistic Logic

International audienceWe investigate the control of evaluation strategies in a variant of the λ-calculus derived through the Curry-Howard correspondence from LJF, a sequent calculus for intuitionistic logic implementing the focusing technique. The proof theory of focused intuitionistic logic yields a single calculus in which a number of known λ-calculi appear as subsystems obtained by restricting types to a certain fragment of LJF. In particular, standard λ-calculi as well as the call-by-push-value calculus are analysed using this framework, and we relate cut elimination for LJF to a new abstract machine subsuming well-known machines for these different strategies

Magnetic and the magnetocaloric properties of Ce1-xRxFe2 and Ce(Fe1-xMx)2 compounds

We have studied selected rare earth doped and transition metal doped CeFe2 compounds by examining their structural, magnetic and magneto-thermal properties. With substitution of Ce by 5 and 10% Gd and 10% Ho, the Curie temperature can be tuned to the range of 267-318 K. Localization of Ce 4f electronic state with rare earth substitutions is attributed for the enhancement of Curie temperature. On the other hand, with Ga and Al substitution at the Fe site, system undergoes paramagnetic to ferromagnetic transition and then to an antiferromagnetic phase on cooling. The magnetocaloric effect across the transitions has been studied from both magnetization isotherms and heat capacity data. It is shown that by choosing the appropriate dopant and its concentration, the magnetocaloric effect around room temperature can be tuned.Comment: 13 pages, 6 figures, 2 table

Modeling of Regional Hydroclimate Change over the Indian Subcontinent: Impact of the Expanding Thar Desert

Abstract The Thar Desert between northwestern India and Pakistan is the most densely populated desert region in the world, and the vast surrounding areas are affected by rapid soil degradation and vegetation loss. The impact of an expanded desert (implemented by changing vegetation type and related greenness fraction, albedo, surface roughness length, emissivity, among others) on the South Asian summer monsoon hydroclimate is investigated by means of 7-month, 4-member ensemble sensitivity experiments with the Weather Research and Forecasting model. It is found that extended desertification significantly affects the monsoon at local and large scales. Locally, the atmospheric water cycle weakens because precipitation, evaporation, and atmospheric moisture convergence all decrease; soil moisture and runoff reduce too. Air temperature cools because of an increase in albedo (the desert makes the area brighter) and a reduction of surface turbulent fluxes; the cooling is partially offset by adiabatic descent, generated to maintain thermodynamic balance and originating at the northern flank of the low-level anticyclone forced by desert subsidence. Regionally, an anomalous northwesterly flow over the Indo-Gangetic Plain weakens the monsoon circulation over northeastern India, causing precipitation to decrease and the formation of an anomalous anticyclone in the region. As a result, the middle troposphere cools because of a decrease in latent heat release, but the ground heats up because of a reduction in cloudiness. At larger scale, the interaction between the anomalous circulation and the mountains leads to an increase in precipitation over the eastern Himalayas and Indochina. The findings of this study reveal that the expansion of the Thar Desert can lead to a pronounced and large-scale impact on summer monsoon hydroclimate, with a potential to redistribute precious water over South Asia.</jats:p

Sharp magnetization step across the ferromagnetic-to-antiferromagnetic transition in doped CeFe<SUB>2</SUB> alloys

Very sharp magnetization step is observed across the field-induced antiferromagnetic-to-ferromagnetic transition in various doped CeFe2 alloys, when the measurement is performed below 5 K. In the higher temperature regime (T&gt;5 K) this transition is quite smooth in nature. Comparing to the recently observed similar behavior in manganites showing colossal magnetoresistance and magnetocaloric material Gd5Ge4, we argue that such a magnetization step is a generalized feature of a disorder-influenced first-order phase transition

Principles and Practices for Groundnut Seed Production in India. Information Bulletin No. 94

Seed production is a specialized farming controlled by various rules and regulations and requires different treatment than the commercial crop. A successful seed producer should be well versed with the crop and its production, packaging and storage technologies and improved varieties and their characteristics besides being aware of various seed acts and regulations in operation in the country. This publication deals with brief introduction of the crop, its origin, taxonomy and reproductive biology and status of groundnut improvement in India to create awareness about the crop and provides information on the procedure of release and notification of varieties, seeds acts and regulations, protection of plant varieties and farmers' rights act, seed systems prevailing in India and different classes of certified seeds and their production practices and quality standard requirements. In the last few sections, the publication deals with the management of seed crop, important varieties released in India, crop processing, packaging and storage. All those who wish to undertake groundnut seed production or wish to promote groundnut seed production will benefit from this publication as it will prepare them well with the basics of seed production in groundnut