On the sets where subharmonic function is large

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Synthesis and Characterization of Silica Supported Co/Nb Bimetallic Catalyst for the Production of Synthetic Fuel via Fischer-Tropsch

Fischer Tropsch synthesis has received considerable attention as it offers a viable alternative to produce liquid fuels and chemicals from non-petroleum carbon resources such as biomass, coal and natural gas. The objective of this work is to synthesize, characterize and study the performance of supported bimetallic cobalt (Co) and niobium (Nb) catalyst in Fischer Tropsch synthesis. Supported bimetallic Co and Nb catalyst have been formulated using reverse microemulsion method. 5wt% of nano particles metal loadings were deposited on silica (SiO2) support. The effect of different metal loading composition of Co and Nb (100:0, 95:5, 90:10, 85:15) on the physiochemical properties of the catalyst has been investigated. The physiochemical properties of the catalyst were studied using field emission electron microscopy (FESEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) and N2 physical adsorption. The FTS performance of the synthesized catalyst was examined in a fixed-bed Microreactor at 220oC, atmospheric pressure and H2/CO ratio of 2:1. Results from the N2 physical adsorption shows that addition of niobium decreases the pore area and volume. It also changes the textural structure from non porous to porous. FESEM and TEM results have shown that the metal particles are well dispersed on the support. The average particle sized ranges from 10.61 nm - 25.5 nm. Introduction of niobium to the catalyst changes its shape from spherical to hexagonal and forms fringes on the particles. This indicates the crystalline structure of cobalt particles. The FTS results exhibit that the CO conversion increases with the amount of Nb in the catalyst. The highest CO conversion is obtained from Sample D (85Co15Nb) which is 70.07%. Sample B (95Co5Nb) showed the lowest selectivity towards CH4 (6.58%) and highest selectivity towards C5+ hydrocarbons i.e. 8.79%. All the samples catalysts display high olefin productivity, indicating that the catalysts synthesized are more suitable for olefin production

Ergodic Capacity of MIMO Correlated Channels in Multipath Fading Environment with known Channel State Information

In this paper we have evaluated the performance of Multiple Input Multiple Output (MIMO) channels in fading environment. Both cases of correlated and uncorrelated MIMO channels are considered under the condition when Channel State Information (CSI) is not known at transmitter and CSI is known at receiver side. We have compared the capacity of 2x2, 3x3 and 4x4 MIMO channels and have shown that capacity increases linearly with increase in the number of antennas at transmitter and receiver side. Increase in the channel capacity is observed because of the uncorrelated channel paths Correlation among the the signals is dependent on the antenna structure and properties and number of the scatterers in the environment. Antenna structure includes the number of elements, the inter-element distance, Angle of Arrival (AOA) and Direction of Arrival (DOA). Additionaly, Correlation increases with the number of scatterers, their distribution, location and degree of movement. Signals with same spatial signature received are considered correlated which reduces the channel capacity. In sum, correlation among the sub-channels causes the degradation in the spectral efficiency of MIMO channels.DOI:http://dx.doi.org/10.11591/ijece.v2i5.151

The relationship between leadership styles and job performance : the moderating role of performance appraisal politics

Drawing upon the leader-member exchange theory and equity, fairness and justice theory, the present study examined the role of performance appraisal politics in moderating both relationships between transactional and transformational leadership styles with job performance. This study also examined the corresponding dimensions of transactional and transformational leadership styles in relation to job performance. Using the quantitative inquiry, the survey method employed had collected a total of 266 responses from bank managers of six large banks in Sindh, Pakistan. They were selected using the stratified random sampling technique. The PLS-SEM analyses revealed that the study supported both the hypothesized relationships between transactional leadership, transformational leadership styles and job performance. Specifically, positive relationships were found between two dimensions of transactional leadership (contingent reward and management by exception [active]) with job performance. Conversely, the significance of relationship between management by exception (passive) and job performance was not supported. However, except intellectual stimulation, remaining four dimensions of transformational leadership styles, namely, idealized influence (attributed), idealized influence (behavior), inspirational motivation, and individualized consideration, were found positively related to job performance. Additionally, while performance appraisal politics moderated the relationship between transformational leadership style and job performance, the reverse was found for the relationship between transactional leadership style and job performance. In general, the results suggested that transformational leadership indeed plays an integral role in facilitating job performance; this relationship is strengthened in the presence of the moderating variable, performance appraisal politics. Finally, the theoretical, methodological, and practical implications were also include

NOMA based resource allocation and mobility enhancement framework for IoT in next generation cellular networks

With the unprecedented technological advances witnessed in the last two decades, more devices are connected to the internet, forming what is called internet of things (IoT). IoT devices with heterogeneous characteristics and quality of experience (QoE) requirements may engage in dynamic spectrum market due to scarcity of radio resources. We propose a framework to efficiently quantify and supply radio resources to the IoT devices by developing intelligent systems. The primary goal of the paper is to study the characteristics of the next generation of cellular networks with non-orthogonal multiple access (NOMA) to enable connectivity to clustered IoT devices. First, we demonstrate how the distribution and QoE requirements of IoT devices impact the required number of radio resources in real time. Second, we prove that using an extended auction algorithm by implementing a series of complementary functions, enhance the radio resource utilization efficiency. The results show substantial reduction in the number of sub-carriers required when compared to conventional orthogonal multiple access (OMA) and the intelligent clustering is scalable and adaptable to the cellular environment. Ability to move spectrum usages from one cluster to other clusters after borrowing when a cluster has less user or move out of the boundary is another soft feature that contributes to the reported radio resource utilization efficiency. Moreover, the proposed framework provides IoT service providers cost estimation to control their spectrum acquisition to achieve required quality of service (QoS) with guaranteed bit rate (GBR) and non-guaranteed bit rate (Non-GBR)

Natural Disasters, Relief Aid, and Household Vulnerability in Pakistan: Evidence from a Pilot Survey in Khyber Pakhtunkhwa

Based on a pilot survey, we analyze the damages caused by floods in Pakistan, 2010, the istribution of aid, and the extent of recovery at he household level. With regard to the nature of damages, we show that flood damages had both between-village and within-village variation, and damages to houses, land (crops), livestock, and other business assets were not highly correlated. In the distribution of aid from outside, we again find substantial between-village and within-village variation - the aid distribution across villages appeared well-targeted toward the severely affected villages, while aid within villages was targeted toward households with larger house damages, but not toward households with larger damages to land, crop, or other assets. The positive aid response to house damages and the negative aid response to the initial wealth level were found but the marginal response of aid to these characteristics was not large. With regard to the recovery from flood damages, we find that aid recipients did not show higher or lower recovery than non-recipients, especially for house damages, which could be due to mixing of a recovery-promoting effect of aid and a selection effect of aid toward households that have more difficulty in recovery. We also show that households who had initially fewer assets and hit by larger flood damages had more difficulty in recovery.natural disaster, relief distribution, resilience, Pakistan

Studies on Collection and Marketing of Morchella (Morels) of Utror-Gabral Valleys, District Swat, Pakistan

This paper is based on a research project carried out to study the collection and marketing status of morels in the remote HinduKush-Himalayan regions of Utror and Gabral, Pakistan. Eight species of morels were found to be collected in the project area during the months of March to July. Morchella conica and Morchella esculenta were the major species collected in the area. These morels are sold in the local markets of Madyan and Mingora, from where they are exported to France, Belgium, Switzerland, Austria and Germany. Morels thus provide a vital source of income to the poor population of Utror and Gabral. Morel collectors include 38.0% women, 37.0% men and 25.0% children. Huge quantities of morels are lost each year due to improper storage and collection techniques

Drug Resistance Pattern in Multidrug Resistance Pulmonary Tuberculosis Patients

Objective: To evaluate accuracy of modified Kenneth Jones scoring criteria (MKJSC) as a screening tool to diagnose tuberculous meningitis in children. Study Design: Cross-sectional study. Place and Duration of Study: Paediatric Medicine, Unit-I, Bahawal Victoria Hospital, Bahawalpur, from May 2006 to March 2007. Methodology: A total of 100 children admitted through emergency in Paediatric Medicine, Unit-I, were included who were having fever and features suggestive of central nervous system (CNS) infection. Lumbar puncture was done in all patients after written consent. Findings of lumbar puncture were taken as gold standard for the diagnosis of TBM. MKJSC was applied on each patient and accuracy determined against the gold standard. Results: Out of 100 children, 47 were diagnosed as TBM on the basis of CSF results. All children had scored 0-7 or above according to MKJSC. A score 1-2, 3-4, 5-6 and 7 or more was obtained in 23, 25, 30 and 22 children respectively. Children who had scored 5 or more received ATT. Accuracy of MKJSC was calculated to be 91%. Conclusion: MKJSC is a simple and accurate tool to improve tuberculous meningitis case detection rate in children