An Adaptive Algorithm to Optimize the Dynamics of IEEE 802.15.4 Networks

Presentado en ICST 2013IEEE 802.15.4 standard is becoming one of the most popular technologies for the deployment of low rate Wireless Personal Area Networks with strong power constraints. In order to reduce the energy consumption, beacon-enabled networks with long network inactive periods can be employed. However, the duration of these inactivity periods, as some other configuration parameters, are conventionally set to default values and remain fixed during the whole network operation. This implies that if they are misconfigured the network will not adapt to changes in the conditions of the environment, particularly to the most determining one, i.e. the traffic load. This paper proposes a simple procedure for the dynamic adaptation of several key parameters of IEEE 802.15.4 networks. Under this procedure, the 802.15.4 parameters are modified as a function of the existing traffic conditions.Spanish National Project No.TEC2009-13763-C02-01

THE CHARACTERIZED CONCEPT OF VAGUE CO-FRAMES

In this paper we introduce vague frame, vague co- frames, vague frame generated by frame and investigate some of its basic properties. In particular, some interesting characterizations closely related to the vague co- frames and vague cut sets on vague co-frame are given also studied their properties. Further we investigate the development of some important results and theorems about vague cut sets on vague co-frame

Water-saving Rice Production Technologies in Krishna Western Delta Command of Andhra Pradesh – An Economic Analysis

The economic analysis of water-saving rice production technologies, viz. system of rice intensification (SRI), semi-dry and rotational irrigation vis-à-vis farmers’ practice has been carried out based on the study executed in Modukuru pilot area of Guntur district of Andhra Pradesh. Among the three water-saving rice production technologies analyzed, the total cost of cultivation has been recorded highest in SRI (Rs 58645/ha), followed by rotational (Rs 47140/ha) and semi-dry (Rs 39321/ha). But, the per hectare yield has been found highest in SRI (6.85 t), followed by semi-dry (6.66 t) and rotational (6.2 t), inferring that all the three technologies have recorded higher yields over farmers’ practice of 5.5 t/ha. However, the net returns and B-C ratio are maximum in semi-dry (Rs 43,484/ha; 1.11), followed by rotational (Rs 30,085; 0.64) and SRI (Rs 26,466/ha; 0.45) methods. Similarly, the water-use efficiency has been found highest in SRI (8.53 kg/ ha-mm), followed by semi-dry (8.02 kg/ha-mm) and rotational (7.33 kg/ ha-mm) methods, while the water-use efficiency benefit (Rs/ha-mm) has been recorded maximum in semi-dry (52.39), followed by SRI (42.08) and rotational (35.56) methods. With the initiation of Andhra Pradesh Water Management Project, Bapatla, the area under semi-dry rice cultivation has been found increasing over a period of four years, from 0.6 ha in 2004-2005 to 22 ha in 2007 -2008.Agricultural and Food Policy,

A theoretical review of the operation of vibratory stress relief with particular reference to the stabilization of large-scale fabrications

Vibratory stress relief (VSR) is widely used on large welded fabrications to stabilize the structures so that they do not distort during further machining or during operational duty. The level of applied stress achieved during VSR on such structures is only 5–10 per cent of the yield stress. It is, therefore, not obvious how these applied loads come to modify the level of residual stress. It is suggested here that the reason for the success of VSR applied to large fabrications lies (a) in the origin of the residual stresses and (b) in the partial relief of these residual stresses by the initiation of the transformation of retained austenite particles (in the size range from 1 to 25 µm) by the movement of dislocations into positions that are favourable for the nucleation of martensite embryos. The shear deformation associated with the transformation of retained austenite into martensite will reduce the residual stress field to the point where the stability of the structure may be assured

Study of Mechanical and Chemical Properties of Biodegradable Fibers before and after Alkali Treatment

The Tensile, Flexural properties, Chemical resistance and Scanning Electron Microscope analysis of bamboo, jute and grass fibers reinforced polyester composites were studied. The effect of alkali treatment of the bamboo, jute and grass fibers on these properties was also studied. It was observed that flexural properties of the hybrid composite increase with bamboo fiber content. These properties found to be higher when alkali treated bamboo fibers were used in the hybrid composites. The elimination of amorphous hemi-cellulose with alkali treated leading to higher crystallinity of the bamboo fibers with alkali treatment may be responsible for these observations. The author investigated the interfacial bonding between Glass/Bamboo reinforced epoxy composites. The effect of alkali treatment on the bonding between Glass/Bamboo composites was also studied. The chemical resistance of Bamboo, jute and grass reinforced polyester composites to acetic acid, Nitric acid, Hydrochloric acid, Sodium hydroxide, Sodium carbonate, Benzene, Toluene, carbon tetrachloride and water was studied. Keywords:Bamboo fiber, jute fiber, grass fiber composites, chemical resistance, polyester, flexural strength, tensile strength, SEM test, chemical resistance test

Rheology of Active-Particle Suspensions

We study the interplay of activity, order and flow through a set of coarse-grained equations governing the hydrodynamic velocity, concentration and stress fields in a suspension of active, energy-dissipating particles. We make several predictions for the rheology of such systems, which can be tested on bacterial suspensions, cell extracts with motors and filaments, or artificial machines in a fluid. The phenomena of cytoplasmic streaming, elastotaxis and active mechanosensing find natural explanations within our model.Comment: 3 eps figures, submitted to Phys Rev Let

Induction of division and differentiation of somatic embryos in the leaf epidermis of Gaillardia picta

Somatic embroys and subsequent plant regeneration were obtained from isolated leaf epidermis of Gaillardia picta. Abaxial and adaxial epidermal peels (monolayer) from 45 days old aseptic seedlings were isolated and segments measuring 5 mm × 3 mm were cultured on B5 basal medium supplemented with various growth regulators such as naphthaleneacetic acid or indolebutyric acid and benzylaminopurine or kinetin. Within 12 h of culture the epidermal cells showed receding of cytoplasm from the walls. After 48 h of incubation 3 or 4 localized zones, each consisting of 3-8 cells that accumulated cytoplasm and stained densely, were observed. Mitotic divisions occurred in these zones on day 3 of culture and localized masses of callus were observed in 95% of the cultures after 10 days. In another 5 days, the callus differentiated somatic embryos or roots, depending on the growth regulators and their concentration in the medium

DEVELOPMENT AND VALIDATION OF RP-HPLC METHOD FOR THE ESTIMATION OF SITAFLOXACIN IN BULK AND PHARMACEUTICAL DOSAGE FORMS

Objective: A simple, specific, and precise reversed phase high performance liquid chromatography method was developed and validated as per the ICH guidelines for the determination of Sitafloxacin in bulk and tablet dosage forms.Methods: The quantitation was carried out by using Symmetry C18 ((5 µm, 100X4.6 mm) column at 300c with Water: Acetonitrile in ratio of 70:30 % V/V as mobile phase. The flow rate is 0.9 mL/min and the estimation was carried out by using PDA detector at 300 nm.Results: The retention time of Sitafloxacin was 2.198 minutes. The linearity was observed from 5-25 μg/mL with correlation coefficient 0.9999. The LOD and LOQ were found to be 0.429μg/mL and 1.415μg/mL respectively.Conclusion: The Statistics data for the Sitafloxacin was concluded that the method was found to be simple, reliable, selective, reproducible and accurate. The method was successfully used for quality control analysis of Sitafloxacin in bulk and Pharmaceutical dosage forms.Â