2,936 research outputs found
High Temperature Limit of the IIA Matrix Model
The high temperature limit of a system of two D-0 branes is investigated. The
partition function can be expressed as a power series in (inverse
temperature). The leading term in the high temperature expression of the
partition function and effective potential is calculated {\em exactly}.
Physical quantities like the mean square separation can also be exactly
determined in the high temperature limit. We comment on SU(3) IIB matrix model
and the difficulties to study it.Comment: Lattice 2000 (Gravity and Matrix Models
Inverse Transport Theory of Photoacoustics
We consider the reconstruction of optical parameters in a domain of interest
from photoacoustic data. Photoacoustic tomography (PAT) radiates high frequency
electromagnetic waves into the domain and measures acoustic signals emitted by
the resulting thermal expansion. Acoustic signals are then used to construct
the deposited thermal energy map. The latter depends on the constitutive
optical parameters in a nontrivial manner. In this paper, we develop and use an
inverse transport theory with internal measurements to extract information on
the optical coefficients from knowledge of the deposited thermal energy map. We
consider the multi-measurement setting in which many electromagnetic radiation
patterns are used to probe the domain of interest. By developing an expansion
of the measurement operator into singular components, we show that the spatial
variations of the intrinsic attenuation and the scattering coefficients may be
reconstructed. We also reconstruct coefficients describing anisotropic
scattering of photons, such as the anisotropy coefficient in a
Henyey-Greenstein phase function model. Finally, we derive stability estimates
for the reconstructions
Evaluation of Naked Barley Landraces for Agro-morphological Traits
Naked barley (Hordeum vulgare var. nudum L.) is a traditional, culturally important, climate-resilient winter cereal crop of Nepal. Evaluation of the naked barely genotypes for yield and disease is fundamental for their efficient utilization in plant breeding schemes and effective conservation programs. Therefore, to identify high yielding and yellow rust resistant landraces of naked barley for hilly and mountainous agro-ecosystem, twenty naked barley landraces collected from different locations of Nepal, were evaluated in randomized complete block design (RCBD) with three replications during winter season of 2016 and 2017 at Khumaltar, Lalitpur, Nepal. Combined analysis of variances revealed that NGRC04902 (3.46 t/ha), NGRC00886 (3.28 t/ha), NGRC02309 (3.21 t/ha) and NGRC06026 (3.10 t/ha) were the high yielding landraces and statistically at par with the released variety 'Solu Uwa' (3.15 t/ha). The landraces namely NGRC00837 (ACI Value: 1.86) was found resistant to yellow rust diseases. Landraces NGRC06034 (131.7 days) and NGRC02363 (130.8 days) were found early maturing and NGRC02306 (94.36 cm) was found dwarf landraces among tested genotypes. These landraces having higher yield and better resistance to yellow rust need to be deployed to farmers' field to diversify the varietal options and used in resistant breeding program to improve the productivity of naked barley for Nepalese farmers
Biotechnology for Conservation and Utilization of Agricultural Plant Genetic Resources in Nepal
Agricultural biodiversity is the basis of human life and food security. Nepal with 577 cultivated species possesses huge diversity at varietal as well as landrace levels. In most agricultural crops the rapid genetic erosion due to several reasons is a common phenomenon. Thus, considering the importance of agricultural biodiversity declared by Convention on Biological Diversity for sustainable food production, National Agriculture Genetic Resources Center (NAGRC) has been established for conservation and sustainable utilization of agricultural biodiversity. This paper thus delineates the application of biotechnological tools adopted by NAGRC for effective and efficient conservation and use of agricultural plant genetic resources (APGRs). Among the adopted technologies, tissue bank using shoot tip culture of vegetatively propagating and recalcitrant crops eg potato, sugarcane, banana, sweet potato, etc are in function. Under the molecular marker technology, currently random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers have been used for developing DNA profiles, identifying duplicates in the collections, assessing genetic diversity and screening accessions against economic traits. DNA bank has also been created for storing DNA of indigenous crops and these DNA can be accessed for research and study. Genotypic database has been developed for chayote, finger millet, wheat and maize for identification and selection of the accessions.Journal of Nepal Agricultural Research Council Vol.3 2017: 49-5
Inverse Diffusion Theory of Photoacoustics
This paper analyzes the reconstruction of diffusion and absorption parameters
in an elliptic equation from knowledge of internal data. In the application of
photo-acoustics, the internal data are the amount of thermal energy deposited
by high frequency radiation propagating inside a domain of interest. These data
are obtained by solving an inverse wave equation, which is well-studied in the
literature. We show that knowledge of two internal data based on well-chosen
boundary conditions uniquely determines two constitutive parameters in
diffusion and Schroedinger equations. Stability of the reconstruction is
guaranteed under additional geometric constraints of strict convexity. No
geometric constraints are necessary when internal data for well-chosen
boundary conditions are available, where is spatial dimension. The set of
well-chosen boundary conditions is characterized in terms of appropriate
complex geometrical optics (CGO) solutions.Comment: 24 page
The Cop Number of the One-Cop-Moves Game on Planar Graphs
Cops and robbers is a vertex-pursuit game played on graphs. In the classical
cops-and-robbers game, a set of cops and a robber occupy the vertices of the
graph and move alternately along the graph's edges with perfect information
about each other's positions. If a cop eventually occupies the same vertex as
the robber, then the cops win; the robber wins if she can indefinitely evade
capture. Aigner and Frommer established that in every connected planar graph,
three cops are sufficient to capture a single robber. In this paper, we
consider a recently studied variant of the cops-and-robbers game, alternately
called the one-active-cop game, one-cop-moves game or the lazy-cops-and-robbers
game, where at most one cop can move during any round. We show that Aigner and
Frommer's result does not generalise to this game variant by constructing a
connected planar graph on which a robber can indefinitely evade three cops in
the one-cop-moves game. This answers a question recently raised by Sullivan,
Townsend and Werzanski.Comment: 32 page
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