Knowledge sharing by entrepreneurs in a virtual community of practice (VCoP)

PurposeThis paper examines how entrepreneurs engage in a Virtual Community of Practice (VCoP) to share knowledge. Intensity of engagement is taken as a proxy to measure the strength of knowledge sharing.Design/methodology/approachThe archival data spanning over a three-year period from ‘Start-up-Nation©’ (a VCoP purposefully setup for entrepreneurs) is used for analysis. A set of indices are introduced to measure participants’ intensity of engagement in terms of message length, message frequency and reciprocity in the knowledge sharing process. Content analysis is employed to test a sample of ‘highly engaged’, ‘moderately engaged’, ‘low engaged’ and ‘not engaged’ discussion topics as part of the on-line discourse.FindingsWe find that entrepreneurs normally use short (fewer than 100 words) or medium (fewer than 250 words) message size to contribute to the discussions. In addition, we find that senior members and discussion moderators play important roles in igniting the ‘reciprocity’ behaviour in stimulating the interest of the community with the topic discussion. We also findthat highly engaged topics usually lead to further discussion threads.Originality/valueThis is the first study of its kind to explore how entrepreneurs engage in a VCoP to share their knowledge and experiences. The set of measurement indices tested here provide a tool for the owner, designer and moderator of the VCoP to measure the utility of their website in terms of its members’ participation. In addition, the set of textual and subjective interventions identified here enable the moderator (administrator) of a VCoP to design effective interventions to facilitate on-line discourse and augment the knowledge sharing process amongst its community members

Dynamic Spectrum Leasing for Bi-Directional Communication: Impact of Selfishness

In this paper, we propose a beamforming-based dynamic spectrum leasing (DSL) technique to improve the spectral utility of bi-directional communication of the legacy/primary spectrum users through the help of colocated secondary users. The secondary users help for a time interval to relay the data between two primary terminals using physical layer network coding and beamforming to attain bi-directional communication with high spectral utility. As a reimbursement, the secondary users, cognitive radios (CRs) in our case, get exclusive access to the primary spectrum for a certain duration. We use Nash bargaining to determine the optimal division of temporal resources between relaying and reimbursement. Moreover, we consider that a fraction of secondary nodes can act selfishly by not helping the primary, yet enjoy the reimbursement time. We measure the utility of the DSL scheme in terms of a metric called time-bandwidth product (TBP) ratio quantifying the number of bits transmitted in direct communication versus DSL. We show that if all secondary nodes act honestly, more than 17-fold increase in the TBP ratio is observed for a sparse CR network. However, in such a network, selfish behavior of CR nodes can reduce the gain by more than a factor of 2

Analysis of dynamic spectrum leasing for coded Bi-directional communication

In this paper, we aim to present a cooperative relaying based two way wireless communication scheme which can provide both spectral and energy efficiency in future wireless networks. To this end, we propose a novel network coding based Dynamic Spectrum Leasing (DSL) technique in which the cognitive secondary users cooperatively relay the primary data for two-way primary communication. In exchange for the relaying services, the primary grants exclusive access to the secondary users for their own activity. We model the random geometry of the ad hoc secondary users using a Poisson point process. We devise a game theoretic framework for the division of leasing time between the primary cooperation and secondary activity phases. We demonstrate that under these considerations and employing network coding, DSL can improve the number of bits that are successfully transmitted by 54% as compared to un-coded direct two way primary communication. Also the energy costs of the proposed DSL scheme are more than 10 times lower. Employing DSL also enables the cognitive users to get reasonable time for their own transmission after increasing the primary spectral and energy efficiency

Energy Consumption Rate based Stable Election Protocol (ECRSEP) for WSNs

In recent few yearsWireless Sensor Networks (WSNs) have seen an increased interest in various applications like border field security, disaster management and medical applications. So large number of sensor nodes are deployed for such applications, which can work autonomously. Due to small power batteries in WSNs, efficient utilization of battery power is an important factor. Clustering is an efficient technique to extend life time of sensor networks by reducing the energy consumption. In this paper, we propose a new protocol; Energy Consumption Rate based Stable Election Protocol (ECRSEP). Our CH selection scheme is based on the weighted election probabilities of each node according to the Energy Consumption Rate (ECR) of each node. We compare results of our proposed protocol with Low Energy Adaptive Clustering Hierarchy (LEACH), Distributed Energy Efficient Clustering (DEEC), Stable Election Protocol (SEP), and Enhanced SEP(ESEP). Our simulation results show that our proposed protocol, ECRSEP outperforms all these protocols in terms of network stability and network lifetime

Evaluating the impact of corporate logos towards corporate reputation: a case of Persia and Mexico

Purpose - This paper examines the impact of corporate logos on corporate image and reputation in creating competitive advantage in the context of Persia and Mexico as emerging markets. This paper provides an extensive links between corporate logo and its dimension and internal stakeholders’ attitudes towards advertisement, familiarity, and recognisability as intermediaries to corporate image and reputation. Design/methodology/approach - A qualitative exploratory approach was taken, comprising 12 face-to-face interviews 14 skype in-depth interviews were conducted with graphic designers, design, communication and marketing consultant in Mexico and Persia based on attribution theory. Findings - The study posits that the more favorable the name, color, typeface and design of the company and color, the more favorable the attitude Mexican consumers have towards the corporate logo, corporate image and reputation. However, in comparison for Persia these factors have less effect on customers’ judgment and behavior, towards the corporate logo, corporate image and reputation. The research findings suggest that the selection of color in a corporate logo is related to its marketing objectives, cultural values, desired customer relationship levels with the organisation, and organisation’s corporate communications. Practical implications - Corporate logo should be considered a constructive tool that can be effectively applied to managing the image and reputation of any organization. Moreover we suggest that regional or cultural variants can play an important role while selecting the logos in different cultures. The results are helpful for communication professionals who deal with organization’s corporate identity, branding, and communication, and aim to enhance the consistency of messages both visual and written within their organization Originality/value - Corporate logo has received little attention in marketing literature and barely been researched in emerging market. This is the first research of its kind to find the effect of the compound logo in emerging markets of Persia and Mexico. It thereby adds to the corporate visual identity literature by developing of the sphere of influence of the corporate logo and its antecedents and consequences (corporate image and corporate reputation)

Preliminary analysis of the diet of wild boar (Sus scrofa L., 1758) in an agro-ecosystem of central Punjab, Pakistan

Hafeez, S., Ashfaq, M

EXTRACTIVE SPECTROPHOTOMETRIC DETERMINATION OF SOME ANTIHISTAMINIC DRUGS FROM PHARMACEUTICAL FORMULATIONS USING ROSE BENGAL

Objective: Simple and sensitive an extractive-spectrophotometric method have been developed for the determination of four important antihistaminic drugs, namely desloratadine (DSL), chlorpheniramine maleate (CPM), diphenhydramine hydrochloride (DPH) and fexofenadine (FXO).Methods: This method is based on the formation of colored ion-pair complexes between the basic nitrogen of the drugs and halofluorescein dyes, namely rose bengal (RB) dye in weak acidic medium. The formed complexes were extracted with dichloromethane measured spectrophotometrically at 550 nm.Results: The reaction conditions were optimized to obtain the maximum color intensity. Beer's law was obeyed with a good correlation coefficient (0.9963-0.9975) in the concentration ranges 1-6, 4-18, 6-16 and 2-22 µg/ml for DSL, CPM, DPH and FXO, respectively. The composition ratio of the ion-pair complexes was found to be 1:1 as established by Job's method.Conclusion: The proposed method was successfully extended to pharmaceutical preparations. Excipients used as additive in commercial formulations did not interfere in the analysis. The proposed method can be recommended for quality control and routine analysis where time, cost effectiveness and high specificity of analytical technique are of great importance.Â

Evaluating the impact of corporate logos towards corporate reputation: a case of Persia and Mexico

Purpose - This paper examines the impact of corporate logos on corporate image and reputation in creating competitive advantage in the context of Persia and Mexico as emerging markets. This paper provides an extensive links between corporate logo and its dimension and internal stakeholders’ attitudes towards advertisement, familiarity, and recognisability as intermediaries to corporate image and reputation. Design/methodology/approach - A qualitative exploratory approach was taken, comprising 12 face-to-face interviews 14 skype in-depth interviews were conducted with graphic designers, design, communication and marketing consultant in Mexico and Persia based on attribution theory. Findings - The study posits that the more favorable the name, color, typeface and design of the company and color, the more favorable the attitude Mexican consumers have towards the corporate logo, corporate image and reputation. However, in comparison for Persia these factors have less effect on customers’ judgment and behavior, towards the corporate logo, corporate image and reputation. The research findings suggest that the selection of color in a corporate logo is related to its marketing objectives, cultural values, desired customer relationship levels with the organisation, and organisation’s corporate communications. Practical implications - Corporate logo should be considered a constructive tool that can be effectively applied to managing the image and reputation of any organization. Moreover we suggest that regional or cultural variants can play an important role while selecting the logos in different cultures. The results are helpful for communication professionals who deal with organization’s corporate identity, branding, and communication, and aim to enhance the consistency of messages both visual and written within their organization Originality/value - Corporate logo has received little attention in marketing literature and barely been researched in emerging market. This is the first research of its kind to find the effect of the compound logo in emerging markets of Persia and Mexico. It thereby adds to the corporate visual identity literature by developing of the sphere of influence of the corporate logo and its antecedents and consequences (corporate image and corporate reputation)

Structured hydrological analysis for targeting fallow evaporation to improve water productivity at the irrigation system level

International audienceThis paper provides results of an application of a holistic systematic approach of water accounting using remote sensing and GIS coupled with ground water modeling to evaluate water saving options by tracking non-beneficial evaporation in the Liuyuankou Irrigation System (LIS) of China. Groundwater rise is a major issue in the LIS, where groundwater levels have risen alarmingly close to the ground surface (within 1 m) near the Yellow River. The lumped water balance analysis showed high fallow evaporation losses and which need to be reduced for improving water productivity. The seasonal actual evapotranspiration (ETs) was estimated by applying the SEBAL algorithm for eighteen NOAA AVHRR-12 images over the year of 1990?1991. This analysis was aided by the unsupervised land use classification applied to two Landsat 5 TM images of the study area. SEBAL results confirmed that a significant amount (116.7 MCM) of water can be saved by reducing ETs from fallow land which will result in improved water productivity at the irrigation system. The water accounting indicator (for the analysis period) shows that the process fraction per unit of depleted water (PFdepleted) is 0.52 for LIS, meaning that 52% of the depleted water is consumed by agricultural crops and 48% is lost through non-process depletion. Finally, the groundwater modeling was applied to simulate three land use and water management interventions to assess their effectiveness for both water savings and impact on the groundwater in LIS. MODFLOW's Zone Budget code calculates the groundwater budget of user-specified subregions, the exchange of flows between subregions and also calculates a volumetric water budget for the entire model at the end of each time step. The simulation results showed that fallow evaporation could be reduced between 14.2% (25.51 MCM) and 45.3% (81.36 MCM) by interventions such as canal lining and ground water pumping. The reduction in non-beneficial ETs volumes would mean that more water would be available for other uses and it would allow the introduction of more surface water supplies in the area through improved water management strategies. This will ultimately lead to improved water productivity of the LIS system

Congestion Control for 6LoWPAN Networks: A Game Theoretic Framework

The Internet of Things (IoT) has been considered as an emerging research area where the 6LoWPAN (IPv6 over Low-Power Wireless Personal Area Network) protocol stack is considered as one of the most important protocol suite for the IoT. Recently, the Internet Engineering Task Force has developed a set of IPv6 based protocols to alleviate the challenges of connecting resource limited sensor nodes to the Internet. In 6LoWPAN networks, heavy network traffic causes congestion which significantly degrades network performance and effects the quality of service (QoS) aspects e.g. throughput, end-to-end delay and energy consumption. In this paper, we formulate the congestion problem as a non-cooperative game framework where the nodes (players) behave uncooperatively and demand high data rate in a selfish way. Then, the existence and uniqueness of Nash equilibrium is proved and the optimal game solution is computed by using Lagrange multipliers and KKT conditions. Based on this framework, we propose a novel and simple congestion control mechanism called game theory based congestion control framework (GTCCF) specially tailored for IEEE 802.15.4, 6LoWPAN networks. GTCCF is aware of node priorities and application priorities to support the IoT application requirements. The proposed framework has been tested and evaluated through two different scenarios by using Contiki OS and compared with comparative algorithms. Simulation results show that GTCCF improves performance in the presence of congestion by an overall average of 30.45%, 39.77%, 26.37%, 91.37% and 13.42% in terms of throughput, end-to-end delay, energy consumption, number of lost packets and weighted fairness index respectively as compared to DCCC6 algorithm