Network Structure and Design in the Deregulated U.S. Airline Industry: an Argument for Re-Regulation?

This paper develops a model to explain and analyze the evolution of network structure (connectivity)and design (flight frequency, aircraft size, prices) in the post-deregulation U.S. airline industry. We show that legacy carriers choice of Hub-and-Spoke networks and the emergence of low cost carriers (LCCs) operating Point-to-Point networks were optimal choices. We demonstrate that LCCs need not necessarily charge lower prices, and their entry impacted legacy carriers’ prices in all markets, even those where there is no direct competition. We show that in response to entry, legacy carriers optimally lower flight frequency, leading to longer wait times between flights for which passengers are compensated by lower prices; conversely, if the entrant later exits, legacy carriers raise flight frequency and therefore prices, which may erroneously appear to be predatory pricing when in fact it is the consequence of optimal network redesign. Finally, we demonstrate that even though low cost carriers lower prices, total social welfare with competing network structures can also be lowered. In other words, the poor financial performance of legacy carriers is not due to their inefficiency per se but due to an efficient Hub-and-Spoke network undermined by competition from inefficient Point-to-Point networks. We argue that social welfare may have been, and still can be, higher if entry and exit in air passenger travel industry is regulated.Networks, Airlines, Regulation

SECURING CENTRALIZED SDN CONTROL WITH DISTRIBUTED BLOCKCHAIN TECHNOLOGY

Software Defined Networks (SDN) advocates segregation of network control logic, forwarding functions and management applications into different planes to achieve network programmability, automated and dynamic flow control in next generation networks. It promotes deployment of novel and augmented network management functions to have flexible, robust, scalable and cost-effective network deployments. All these features introduce new research challenges and require secure communication protocols among the segregated network planes. This manuscript focuses on the security issue of southbound interface which operates between the SDN control and data plane. We have highlighted the security threats associated with an unprotected southbound interface and the issues related with the existing TLS based security solution. A lightweight blockchain based decentralized security solution is proposed for southbound interface to secure the resources of logically centralized SDN controllers and distributed forwarding devices from opponents. The proposed mechanism can operate in multi-domain SDN deployment and can be used with wide range of network controllers and data plane devices. In addition to it, the proposed security solution is analyzed in terms of security features, communication and reauthentication overhead

Human Verification using Multiple Fingerprint Texture Matchers

This paper presents a multimodal biometric verification system using multiple fingerprint matchers. Theproposed verification system is based on multiple fingerprint matchers using Spatial Grey LevelDependence Method and Filterbank-based technique. The method independently extract fingerprinttexture features to generate matching scores. These individual normalized scores are combined into afinal score by the sum rule and the final score is eventually used to effect verification of a person asgenuine or an imposter. The matching scores are used in two ways: in first case equal weights are assignedto each matching scores and in second case user specific weights are used. The proposed verificationsystem has been tested on fingerprint database of FVC2002. The experimental results demonstrate that theproposed fusion strategy improves the overall accuracy of the system by reducing the total error rate of thesystem.Keywords: - Multimodal biometric System, Fingerprint verification, SGLDM, Filterbank matching, Scorelevel fusion, Sum rule

Synthesis, characterization and antimicrobial studies of imine derivatives of amoxicillin

Some novel imine derivatives (1-14) of a broad spectrum antibiotic amoxicillin were prepared by condensation with different carbonyl compounds. The amoxicillin imine derivatives were characterized using elemental analysis and spectroscopic techniques such as FT-IR and 1H NMR. The prepared imine derivatives were evaluated for antimicrobial activities against some pathogens using disc diffusion method. The results of present studies demonstrate enhanced antimicrobial activity of the novel imine derivatives of amoxicillin as compared to the parent drug

A Simple and Cost-Effective EPON-Based Next Generation Mobile Backhaul RAN Architecture

This study proposes a novel, simple and cost-effective PON-based next generation mobile backhaul RAN architecture that enables redistribution of some of the intelligence currently centralized in the Mobile Packet Core (MPC) platform out into the access nodes of the RAN. Specifically, this work proposes a fully distributed ring-based EPON architecture that enables the support of a converged PON-4G/5G mobile WiMAX/LTE access networking transport infrastructure to seamlessly backhaul both mobile and wireline multimedia traffic and services

Hepatitis B vaccination status of health care workers and their antiHBs titres - A cross sectional study

Back ground: The risk from occupational exposure to HBV infection is 2-4 times higher in HCW’s. A protective vaccine with a reported efficacy of 95% is available. Yet many HCW’s in developing countries remain non vaccinated, incompletely vaccinated or if vaccinated unaware of their post vaccination anti HBs status. Estimation of protective immune response following vaccination is essential to clear the misconceptions regarding booster dose of vaccine and non responder state which prevails among the HCW’s. Objective: The present study is designed to assess the hepatitis B vaccination rates in HCW’s and their antiHBs titres. Material and methods: A cross sectional study on 87 subjects was carried out at a tertiary care hospital by testing their sera for HBsAg & anti HBs levels. Results: None of the HCW’s were found to be HBsAg positive. Vaccination rate observed was 79%. Most vaccinated were the doctors and least the paramedics. Among doctors variation within the occupational groups was noticed. More number of males and young subjects were vaccinated and protected. Only 49% of the vaccinated HCW’s were vaccine compliant and 35% of these were protected. Factors like age, sex and time since last dose of vaccine influenced the anti HBs titres. None were aware of their anti HBs titres post vaccination. Conclusion: The study group involves only a small number of HCW’s but the findings are significant. Keeping in mind the annual global hepatitis B infection rates in HCW’s in developing countries we recommend the health care authorities to strengthen the existing educational programmes on Hepattis B infection which improves the awareness levels and thereby increases the vaccine rates. Further to make essential post vaccination assessment of antiHBs titres and its documentation to clear misconceptions regarding booster dose of vaccine

Prevalence of thyroid dysfunction in type 2 diabetes mellitus: a case control study

Background: Diabetes mellitus and thyroid disorders are the most common endocrine disorders worldwide. Various studies have found that diabetes and thyroid disorders mutually influence each other and both disorders tend to coexist. So, we conducted a study to find out the prevalence of thyroid disorders in patients of type 2 diabetes mellitus.Methods: This study was conducted on 100 diabetic patients and 100 controls. All the participants were evaluated for thyroid dysfunctions by testing thyroid profile. The correlation of prevalence of thyroid disorder with age distribution, gender distribution, BMI, duration of diabetes and HbA1C was then done.Results: The prevalence of thyroid dysfunctions were high in diabetic patients compared to controls (29% versus 9%, P value <0.001). Most common thyroid disorder in diabetic patients was subclinical hypothyroidism (16%) while least common was hyperthyroidism (1%). The levels of serum T3 and T4 were significantly low while serum TSH levels were significantly high in diabetic group compared to control group. Prevalence of thyroid disorders in diabetics were significantly more in patients with age ≥ 50 years, more in females, more in patients with BMI ≥ 30 and more in patients with duration of diabetes ≥ 5 years. The association of prevalence of thyroid disorders with HBA1C was not significant.Conclusions:Current study showed high prevalence of thyroid dysfunctions in diabetic patients. We conclude that screening for thyroid dysfunction among patients with diabetes mellitus should be routinely performed, so as to recognize these dysfunctions early.