Routing Protocols in Delay Tolerant Networks: Comparative and Empirical Analysis

Wireless Personal Communications - A Delay Tolerant Network (DTN) is a network capable of handling long delays and data loss efficiently in various challenged scenarios and environments. Owing to...     

A QoS Aware Resource Placement Approach Inspired on the Behavior of the Social Spider Mating Strategy in the Cloud Environment

Wireless Personal Communications - The efficient management of resource sharing plays a crucial role in the cloud execution environment. The constraints such as heterogeneity and dynamic nature of...     

Structural and Luminescence Studies on Barium Sodium Borosilicate Glasses Containing Uranium Oxides

Barium sodium borosilicate glasses containing different amounts of uranium oxides were prepared by conventional melt quench method and investigated for their structural aspects by ²⁹Si and ¹¹B MAS NMR technique combined with steady‐state luminescence and lifetime measurements. Based on MAS NMR studies, it is confirmed that uranium ions act as network modifier up to 15 wt% and beyond which a separate uranium containing phase is formed. From the luminescence studies, it is inferred that uranyl species is in a highly distorted environment. For more than 15 wt% uranium oxide incorporation, weaker U–O–U linkages are formed at the expense stronger U–O–Si/B linkages, as suggested by the excited state lifetime value of the uranyl species as well as red shift in emission peak maximum. For glass samples containing more than 25 wt% uranium oxides, crystalline barium uranium silicate gets phase separated from glass matrix as confirmed by XRD studies.     

Design and performance evaluation of biogas stove for community cooking application

Matured biogas production technology has led to the development of a number of biogas appliances for lighting, power generation, and cooking. The most promising among them is the biogas stove, to meet the energy requirement for cooking application at domestic as well as at the community level. In this paper, an attempt has been made to design and develop a community biogas stove for baking chapatti (bread) or other food items on a hotplate for canteen or community purposes. The performance of the stove was evaluated by using a 25 m³ floating type biogas plant at Asha Dham Asharm, Udaipur, India. The gas consumption rating of the developed stove was 1 m³ (19 MJ/h) and the cooking efficiency of the stove was recorded to be about 43.96%.     

Parametric Study of Jatropha Seeds for Biodiesel Production by Reactive Extraction

The purpose of the present study was to reduce the cost and increase the efficiency of biodiesel production by reactive extraction (in situ) of Jatropha seeds. Oil from the seeds was extracted and reacted in a single step. Experimental studies have been carried out to maximize the yield of biodiesel by varying the reaction parameters viz. seed size (<0.85 mm to >2.46 mm), seed/solvent ratio (w/w) (1:2.6–1:7.8) and catalyst concentration (0.05–0.1 M). Under the optimized conditions: seed size (>2.46 mm), seed/solvent ratio (w/w) (1:7.8), catalyst concentration (0.1 M) and reaction time 1 h, approximately 98% conversion to biodiesel was achieved meeting International (ASTM) as well as National (BIS) specifications. The results were supported by HPLC analysis.     

Study of synthetic complex esters as automotive gear lubricants

A number of di‐ and triol‐centered polyols such as 2, 2‐dimethyl‐1, 3‐propane diol, 2, 2‐diethyl‐1, 3‐propane diol and 1, 1, 1‐tris hydroxy methyl propane complex esters have been synthesized using di‐carboxylic acids like adipic and sebacic acids (C₆–C₁₀) and 2‐ethyl 1‐hexanol with indigenous ion‐exchange resin (Indion‐130) catalyst. The applicability of these esters as automotive gear lubricants has been evaluated. The products were found to be compatible with extreme pressure additives. In addition, the products are readily biodegradable. Copyright © 2008 John Wiley & Sons, Ltd.     

Effect of low frequency ultrasonic assisted extraction on the quality of seed oils of Indian origin

The study gives an insight into the effect of low frequency ultrasonic enhancement of solvent extraction on the quality of non-edible oils (Jatropha and Pongamia as model seed varieties) in comparison to conventional methods of extraction i.e. direct reflux or soxhlet extraction using hexane. A series of experiments have been carried out to study the effect of variables; solute to solvent ratio (1:2.5-1:10) and reaction time (30 s-60 min) on the yield of oil. The quality of oil extracted by different methods have been assessed by determining the acid value of oil by ASTM D-974/04 method, a measurement of triglyceride and fatty acid degradation, by the presence of phorbol esters in Jatropha curcas and phenolic compounds in Pongamia oil analyzed using HPLC. Under optimized conditions solute to solvent ratio of 1:10 (w/v), 3 min extraction time yields > 95% pure oil having < 1% FFA in Jatropha curcas and 30 s extraction time in Pongamia seed yields oil with less than 2% FFA in comparison to conventional method of extraction in 16 h.     

Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia

The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16–20th weeks, 26–30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α‐linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n‐6 fatty acids were higher (p < 0.05) at 16–20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n‐3, 22:6n‐3, 24:1n‐9, MUFA, and total n‐3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n‐3 and 24:1n‐9 at 16–20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.     

Developing maintainable expert systems using case-based reasoning

Abstract: Maintainability problems associated with traditional software systems are exacerbated in rule-based systems. The very nature of that approach — separation of control knowledge and data-driven execution — hampers maintenance. While there are widely accepted techniques for maintaining conventional software, the same is not true for rule-based systems. In most situations, both a knowledge engineer and a domain expert are necessary to update the rules of a rule-based system. This paper presents, first, an overview of the software engineering techniques and object-oriented methods used in maintaining rule-based systems. It then discusses alternate paradigms for expert system development. The benefits of using case-based reasoning (from the maintenance point of view) are illustrated through the implementation of a case-based scheduler. The main value of the scheduler is that its knowledge base can be modified by the expert without the assistance of a knowledge engineer. Since changes in application requirements can be given directly to the system by the expert, the effort of maintaining the knowledge base is greatly reduced.