Adaptive QoS scheduling in wireless cellular networks

Quality of service (QoS) has been always controversial in resource shared networks. Scheduling as a packet prioritizing mechanism at Data Link Layer (DLL) contributes to QoS guarantee provisioning significantly. In this paper, a novel packet scheduler is developed in wireless cellular networks. The proposed scheme provides QoS-guaranteed service for the applications running on the sensor nodes in all the three aspects of QoS, i.e. data rate, packet loss and packet delay with regard to jitter simultaneously. We establish a three-dimensional space with certain basis vectors for QoS and introduce the efficient point of performance in terms of QoS provisioning in that space. Then we develop a generalized metric, the QoS-deviation, which is the Euclidean distance between the QoS work point of flows and the QoS efficient point in the proposed space. Based on this metric, a novel scheduling approach, namely AQDC, is designed which makes it possible to tune the trade-off between QoS provisioning and throughput optimization in an adaptive manner depending on the current Cell QoS-deviation level (CDL). Furthermore, we also develop another scheduler, namely ARTC, which is the residual-time version of the AQDC scheduler. Finally, a QoS-deviation-based CAC policy will be introduced which can be applied to all schedulers without any consideration about their structure and can be employed in cellular packet switched networks.     

Diagnostic pre-treatment procedure for simultaneous cyanide leaching of gold and silver from a refractory gold/silver ore

This study investigates the optimization of simultaneous dissolution of gold and silver from a refractory gold ore through determination of pre-treatment stages. Based on the mineralogical studies (thin layer and polished section) and chemical analysis on the ore sample, a “diagnostic leaching” procedure was designed. Results from diagnostic leaching suggest that the most effective pre-treatment agents for gold and silver are ferric chloride and sulfuric acid media, respectively. Optimum conditions for the simultaneous dissolution of gold and silver were determined using a two factorial design technique. Pre-treatments with sulfuric acid and ferric chloride reagents increased the efficiency of the dissolution of gold from 54.7% to 82% and silver from 37.4% to 81.6%.     

Rheological interactions between Lallemantia royleana seed extract and selected food hydrocolloids

BACKGROUND: Lallemantia royleana (Balangu) is a mucilaginous endemic plant which is grown in different regions of world. The flow behaviour of Balangu seed extract (BSE) and its mixture with xanthan, guar and locust bean gums at 1:3, 1:1 and 3:1 ratios, in addition to control samples (0% BSE), were evaluated. To describe the rheological properties of samples, the power law model was fitted on apparent viscosity–shear rate data. To evaluate the interaction between BSE and selected hydrocolloids in dilute solutions, the relative viscosity was also investigated. RESULTS: There was no significant difference between the consistency coefficient of guar and locust bean solutions and their blends substituted with 250 g kg^?1 BSE. The BSE–xanthan mixture at 1:3 and 1:1 ratios had consistency index equal to xanthan solution. BSE–locust bean gum at all ratios, BSE–xanthan at 1:3 ratio and BSE–guar gum at 1:1 and 3:1 ratios indicated relative viscosity lower than values calculated assuming no interaction. The intrinsic viscosity value of BSE was determined 3.50 dL g^?1. CONCLUSION: The apparent viscosities of BSE, selected hydrocolloids and their blends were the same at a shear rate of 293 s^?1 and the commercial gums can be substituted by 250 g kg^?1 and 500 g kg^?1 BSE. Copyright © 2011 Society of Chemical Industry     

In vivo assessment of basal and drug-induced dopamine release in cortical and subcortical regions of the anesthetized primate

There is an acute interest in studying the functional characteristics of dopamine systems in the cortex of primates. In particular, the prefrontal cortical dopamine projections have received a great deal of attention. This system is essential for proper functioning of the prefrontal cortex, and dysfunction within the system may be involved in some psychiatric and neurological illnesses. In vivo assessments of cortical dopamine in the primate have been scarce. This has been due, in part, to technical difficulties associated with these studies and with quantifying the relatively low levels of dopamine found in cortical regions. In the present study, intracerebral microdialysis was utilized to assess the extracellular concentration of dopamine in cortical and subcortical areas of the pentobarbital-anesthetized rhesus monkey. Basal extracellular dopamine levels were consistently detected in the medial prefrontal cortex, premotor cortex, and caudate-putamen. The basal extracellular concentration of dopamine in the dorsolateral prefrontal cortex was reliably detected in 1 of 4 animals. Intravenous administration of amphetamine (1 mg/kg) enhanced extracellular dopamine levels in the caudate-putamen area by more than 20-fold. In cortical areas, amphetamine's effect was less profound: An increase of 400-500 percent over basal extracellular dopamine levels was observed in each region. These studies demonstrate the feasibility of microdialysis for detecting extracellular fluxes of dopamine in the cortex of nonhuman primates. They further provide direct evidence that the dopamine released within the prefrontal cortex and the premotor cortex of nonhuman primates responds to pharmacological manipulation.     

Newly designed tissue adhesion prevention technology based on photocurable mucopolysaccharides. In vivo evaluation

Tissue adhesion after surgery occasionally causes serious complications. The authors have been developing photocurable mucopolysaccharides for a tissue adhesion prevention material that meets requirements such as nonadherent surface characteristics, biocompatibility, biodegradability in accordance with the wound healing rate, and nontoxicity. Mucopolysaccharides (hyaluronic acid and chondroitin sulfate) partially derived with photoreactive groups, such as cinnamate or thymine, were subjected to ultraviolet (UV) irradiation to produce water insoluble gels via intermolecular photodimerization of photoreactive groups. Photocured films that covered injured liver surfaces of rats were implanted for as long as 4 weeks and histologically evaluated. In vivo performance, including tissue adhesion prevention, biodegradability, and mechanical flexibility of the films, was found to be controlled by the type of mucopolysaccharides, the type of photoreactive groups, and their degrees of substitution (DS). Photocured films with lower DS, which had high water swellability and flexibility, prevented tissue adhesion and exhibited enhanced biodegradability. As an increase in DS occurred, tissue adhesion prevention, biodegradability, and mechanical flexibility were reduced. Control of the biodegradation rate was feasible. Minimum inflammatory reaction was noticed.     

Psychology in the three worlds: As reflected by the crisis in social psychology and the move toward indigenous third-world psychology.

The three worlds in which psychologists research and practice are distinguished: The first consists of the United States, the second comprises the other developed nations, and third is made up of the developing countries. The three worlds have unequal capacities for producing and disseminating psychological knowledge and for shaping psychology; the dominant power is the first world. The crisis in western social psychology is reviewed and is interpreted as partly arising from an attempt by the second world to establish a distinct social psychology, independent of that of the United States. The movement toward a third-world psychology indicates a possible challenge to the domination of first- and second-world psychologies in third-world societies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling of rough-surface effects in an optical turning mirrorusing the finite-difference time-domain method

A finite-difference time-domain (FDTD) method is applied to calculate the forward-reflected and back-reflected powers of a guided mode from a rough turning mirror in a bent waveguide of a high-power laser array. By segmenting this large problem into a number of smaller problems, the simulation region can be shrunk to a small area containing only the details of the rough-surface mirror. By launching the incident wave judiciously, the computation time grows linearly with the length of the mirror. A farfield transformation of the calculated time-domain scattered field yields forward-reflected and back-reflected powers. The computer time needed to analyze this large turning-mirror system is reduced to about 3 min of CRAY time, compared to several hours for a brute-force approach using a full mesh     

Optimum strength distribution for seismic design of tall buildings

This paper examines the effects of strength distribution pattern on seismic response of tall buildings. It is shown that in general for an MDOF structure there exists a specific pattern for height‐wise distribution of strength and stiffness that results in a better seismic performance in comparison with all other feasible patterns. This paper presents a new optimization technique for optimum seismic design of structures. In this approach, the structural properties are modified so that inefficient material is gradually shifted from strong to weak areas of a structure. This process is continued until a state of uniform deformation is achieved. It is shown that the seismic performance of such a structure is optimal, and behaves generally better than those designed by conventional methods. The optimization algorithm is then conducted on shear building models with various dynamic characteristics subjected to a group of severe earthquakes. Based on the results, a new load pattern is proposed for seismic design of tall buildings that is a function of fundamental period of the structure and the target ductility demand. The optimization method presented in this paper could be useful in the conceptual design phase and in improving basic understanding of seismic behavior of tall buildings. Copyright © 2007 John Wiley & Sons, Ltd.     

Genetic-based multi-objective optimization of alkylation process by a hybrid model of statistical and artificial intelligence approaches

The purpose of this research is to find the optimal operating point in the production process of the cumene. Therefore, the production process was optimized through statistical and genetic algorithm-based methods. The performance of an alkylation reactor was optimized through maximizing the yield of cumene production. Response surface methodology (RSM) with design type of central composite was applied for design of experiment, modelling, and optimizing the process. The analysis of variance (ANOVA) was performed for finding the important operative parameters as well as their effects. The effects of three parameters including temperature, reactor length, and pressure on the alkylation process were investigated. Further, two types of feed-forward neural network were applied to model the alkylation reactor. To develop the neural network model, leave-one-out method was used. The best prediction performance belonged to a fitting network with 2 and 8 neurons in the hidden layer, respectively. This model was used for optimizing the performance of the alkylation reactor. The statistical and artificial intelligence systems were capable of prediction of cumene production yield in different conditions with R² of 0.9098 and 0.9986, respectively. Genetic algorithm-based optimization was performed by the developed neural network model. The maximum accessible value of cumene production yield was 0.7771, which can be achieved when the temperature, length of reactor, and column pressure are 160°C, 2 m, and 4000 kPa, respectively. By finding the optimal operating point in the cumene production process, capital cost, energy consumption, and other operating costs can be significantly reduced.