858 research outputs found
Zone Melting Studies of Organic Eutectic Mixtures: Naphthalene-Catechol & Naphthalene-p-Chloronitrobenzene Systems
819-82
Allocative Efficiency of Resource use on Beekeeping in Chitwan District of Nepal
Agriculture is facing with increasing pollinators decline all over the world affecting the functioning of regulatory and production service of pollination in adverse manner. Study on ways to conserve pollinating agents like bee is crucial in modern intensive agriculture. In this context a study was conducted to estimate the productivity and resource use efficiency of bee keeping in Chitwan district of Nepal. The study used data collected from randomly selected 48 bee keepers using face to face interview technique in the year 2014. Descriptive statistics, gross margin analysis, benefit cost analysis and multiple regression analysis using Cob-Douglas form were employed to achieve study objectives. It was found that farmers were rearing honey bee on an average of about 34 hives per farm with annual productivity of bee products equivalent to 36 Kg honey per hive. Gross margin of beekeeping in the research area was found to be NRs. 3111.55 per hive with undiscounted benefit cost ratio of 1.71. Human labour use, expenditure on sugar, drugs and comb foundation and; migration cost were significantly contributing to the productivity of beekeeping and were required to increase their use by 39%, 34% and 74%, respectively to achieve optimum profit. It was suggested to increase the level of all variable inputs through loan, subsidy and insurance to promote beekeeping enterprise in the study area for ensuring optimum profit to farmers and conservation of the most important agent of pollination
Quantum state estimation and large deviations
In this paper we propose a method to estimate the density matrix \rho of a
d-level quantum system by measurements on the N-fold system. The scheme is
based on covariant observables and representation theory of unitary groups and
it extends previous results concerning the estimation of the spectrum of \rho.
We show that it is consistent (i.e. the original input state \rho is recovered
with certainty if N \to \infty), analyze its large deviation behavior, and
calculate explicitly the corresponding rate function which describes the
exponential decrease of error probabilities in the limit N \to \infty. Finally
we discuss the question whether the proposed scheme provides the fastest
possible decay of error probabilities.Comment: LaTex2e, 40 pages, 2 figures. Substantial changes in Section 4: one
new subsection (4.1) and another (4.2 was 4.1 in the previous version)
completely rewritten. Minor changes in Sect. 2 and 3. Typos corrected.
References added. Accepted for publication in Rev. Math. Phy
Inconsistency of the MLE for the joint distribution of interval censored survival times and continuous marks
This paper considers the nonparametric maximum likelihood estimator (MLE) for
the joint distribution function of an interval censored survival time and a
continuous mark variable. We provide a new explicit formula for the MLE in this
problem. We use this formula and the mark specific cumulative hazard function
of Huang and Louis (1998) to obtain the almost sure limit of the MLE. This
result leads to necessary and sufficient conditions for consistency of the MLE
which imply that the MLE is inconsistent in general. We show that the
inconsistency can be repaired by discretizing the marks. Our theoretical
results are supported by simulations.Comment: 27 pages, 4 figure
Droplet actuation induced by coalescence: experimental evidences and phenomenological modeling
This paper considers the interaction between two droplets placed on a
substrate in immediate vicinity. We show here that when the two droplets are of
different fluids and especially when one of the droplet is highly volatile, a
wealth of fascinating phenomena can be observed. In particular, the interaction
may result in the actuation of the droplet system, i.e. its displacement over a
finite length. In order to control this displacement, we consider droplets
confined on a hydrophilic stripe created by plasma-treating a PDMS substrate.
This controlled actuation opens up unexplored opportunities in the field of
microfluidics. In order to explain the observed actuation phenomenon, we
propose a simple phenomenological model based on Newton's second law and a
simple balance between the driving force arising from surface energy gradients
and the viscous resistive force. This simple model is able to reproduce
qualitatively and quantitatively the observed droplet dynamics
Asymptotic estimation theory for a finite dimensional pure state model
The optimization of measurement for n samples of pure sates are studied. The
error of the optimal measurement for n samples is asymptotically compared with
the one of the maximum likelihood estimators from n data given by the optimal
measurement for one sample.Comment: LaTeX, 23 pages, Doctoral Thesi
Harmonic Analysis of Boolean Networks: Determinative Power and Perturbations
Consider a large Boolean network with a feed forward structure. Given a
probability distribution on the inputs, can one find, possibly small,
collections of input nodes that determine the states of most other nodes in the
network? To answer this question, a notion that quantifies the determinative
power of an input over the states of the nodes in the network is needed. We
argue that the mutual information (MI) between a given subset of the inputs X =
{X_1, ..., X_n} of some node i and its associated function f_i(X) quantifies
the determinative power of this set of inputs over node i. We compare the
determinative power of a set of inputs to the sensitivity to perturbations to
these inputs, and find that, maybe surprisingly, an input that has large
sensitivity to perturbations does not necessarily have large determinative
power. However, for unate functions, which play an important role in genetic
regulatory networks, we find a direct relation between MI and sensitivity to
perturbations. As an application of our results, we analyze the large-scale
regulatory network of Escherichia coli. We identify the most determinative
nodes and show that a small subset of those reduces the overall uncertainty of
the network state significantly. Furthermore, the network is found to be
tolerant to perturbations of its inputs
Low temperature synthesis, magnetic and magnetotransport properties of (La1-xLux)0.67Ca0.33MnO3 (0 < x < 0.12) system
We have been able to synthesize Lu+3 substituted La0.67Ca0.33MnO3 (LCMO) by
an auto-combustion method. Synthesis of this compound is not successful by
conventional ceramic or other chemical methods. Magnetic and electrical
transport properties of the Lu substituted LCMO [(La1-xLux)0.67Ca0.33MnO3 (0 <
x < 0.12)] system have been investigated and compared with those of the Y+3,
Pr+3, Dy+3 and Tb+3 substituted LCMO systems. All the compounds show a
ferromagnetic metal to paramagnetic insulator transition at TC. The tolerance
factor reduces from 0.917 for x = 0 to 0.909 for x = 0.12 and for this range
all are ferromagnetic metals indicating the dominance of the coupling between
spins due to double exchange over the antiferromagnetic superexchange
interaction. The transition temperatures and magnetization decrease as the Lu
concentration increases. This is satisfactorily accounted for on the basis of
transition from ferromagnetic at x = 0 to canted spin order for x > 0. All the
samples show higher magnitude of MR compared to that in pure LCMO at 80 kOe
field in the temperature range of 5 to 320K. A fairly high value of low field
magnetoresistance (LFMR) of about 30% is obtained in all the samples at a field
less than 5 kOe.Comment: Total 35 pages of text and figure
Considering the impact of situation-specific motivations and constraints in the design of naturally ventilated and hybrid buildings
A simple logical model of the interaction between a building and its occupants is presented based on the principle that if free to do so, people will adjust their posture, clothing or available building controls (windows, blinds, doors, fans, and thermostats) with the aim of achieving or restoring comfort and reducing discomfort. These adjustments are related to building design in two ways: first the freedom to adjust depends on the availability and ease-of-use of control options; second the use of controls affects building comfort and energy performance. Hence it is essential that these interactions are considered in the design process. The model captures occupant use of controls in response to thermal stimuli (too warm, too cold etc.) and non-thermal stimuli (e.g. desire for fresh air). The situation-specific motivations and constraints on control use are represented through trigger temperatures at which control actions occur, motivations are included as negative constraints and incorporated into a single constraint value describing the specifics of each situation. The values of constraints are quantified for a range of existing buildings in Europe and Pakistan. The integration of the model within a design flow is proposed and the impact of different levels of constraints demonstrated. It is proposed that to minimise energy use and maximise comfort in naturally ventilated and hybrid buildings the designer should take the following steps: 1. Provide unconstrained low energy adaptive control options where possible, 2. Avoid problems with indoor air quality which provide motivations for excessive ventilation rates, 3. Incorporate situation-specific adaptive behaviour of occupants in design simulations, 4. Analyse the robustness of designs against variations in patterns of use and climate, and 5. Incorporate appropriate comfort standards into the operational building controls (e.g. BEMS)
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