Robust Face Representation and Recognition Under Low Resolution and Difficult Lighting Conditions

This dissertation focuses on different aspects of face image analysis for accurate face recognition under low resolution and poor lighting conditions. A novel resolution enhancement technique is proposed for enhancing a low resolution face image into a high resolution image for better visualization and improved feature extraction, especially in a video surveillance environment. This method performs kernel regression and component feature learning in local neighborhood of the face images. It uses directional Fourier phase feature component to adaptively lean the regression kernel based on local covariance to estimate the high resolution image. For each patch in the neighborhood, four directional variances are estimated to adapt the interpolated pixels. A Modified Local Binary Pattern (MLBP) methodology for feature extraction is proposed to obtain robust face recognition under varying lighting conditions. Original LBP operator compares pixels in a local neighborhood with the center pixel and converts the resultant binary string to 8-bit integer value. So, it is less effective under difficult lighting conditions where variation between pixels is negligible. The proposed MLBP uses a two stage encoding procedure which is more robust in detecting this variation in a local patch. A novel dimensionality reduction technique called Marginality Preserving Embedding (MPE) is also proposed for enhancing the face recognition accuracy. Unlike Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), which project data in a global sense, MPE seeks for a local structure in the manifold. This is similar to other subspace learning techniques but the difference with other manifold learning is that MPE preserves marginality in local reconstruction. Hence it provides better representation in low dimensional space and achieves lower error rates in face recognition. Two new concepts for robust face recognition are also presented in this dissertation. In the first approach, a neural network is used for training the system where input vectors are created by measuring distance from each input to its class mean. In the second approach, half-face symmetry is used, realizing the fact that the face images may contain various expressions such as open/close eye, open/close mouth etc., and classify the top half and bottom half separately and finally fuse the two results. By performing experiments on several standard face datasets, improved results were observed in all the new proposed methodologies. Research is progressing in developing a unified approach for the extraction of features suitable for accurate face recognition in a long range video sequence in complex environments

Design of a microstrip antenna on Duroid 5870 substrate material for Ku and K-band applications

U ovom je radu prikazana mikrostrip antena na podlozi Duroid 5870 za aplikacije Ku i K pojasa. Predložena se antena sastoji od kružnih i pravokutnih nizova tiskanih na dielektričnom materijalu podloge Duroid 5870, a pobuđuje ju 50 Ω mikrostrip dalekovod. HFSS elektromagnetski solver visoke frekvencije uzet u obzir u ovoj studiji temelji se na metodi konačnih elemenata (MKE). Antena generira dvije odvojene rezonantne frekvencije za pokrivanje Ku i K-pojasa. Ima područje impedancije (2:1 VSWR) od 1,11 GHz (16,14 ÷ 15,03 GHz) na donjem pojasu i širinu pojasa od 1,15 GHz (20,99 ÷ 19,84 GHz) na gornjem pojasu. Postigla je stabilan kružni dijagram zraćenja u operativnom frekvencijskom pojasu. Predstavljeni su i detaljno raspravljeni učinkovitost, raspodjela struje, VSWR te povratni gubitci predložene antene.A microstrip antenna on Duroid 5870 substrate material has been presented for Ku and K-band applications in this paper. The proposed antenna has consisted of circular and rectangular slots printed on Duroid 5870 dielectric substrate material and excited by a 50 Ω microstrip transmission line. High frequency electromagnetic solver HFSS has been taken into account in this study based on the Finite Element Method (FEM). The antenna has generated two separate resonant frequencies to cover Ku and K-band. It has an impedance bandwidth (2:1 VSWR) of 1,11 GHz (16,14 ÷ 15,03 GHz) on the lower band and a bandwidth of 1,15 GHz (20,99 ÷ 19,84 GHz) on the upper band. It has achieved a stable omni-directional radiation pattern in the operating frequency band. The efficiency, current distribution, VSWR, return loss of the proposed antenna have been presented and discussed in detail

Estimating the Environmental Cost of Shrimp Farming in Coastal Areas of Chittagong and Coxs bazaar in Bangladesh

During the last three decades, shrimp has remained one of the major export items in Bangladesh. It contributes to the development of this country by enhancing export earnings and promoting employment. However, coastal wetlands and agricultural lands are used for shrimp culture, which reduces agricultural opportunity and peasants income, and destroys the mangroves and coastal eco-system. These are the external environmental costs that are not reflected in farmers price and output decisions. This study has aimed to estimate those external environmental costs through the contingent valuation method. The calculated environmental cost of shrimp farming is USD 13.66 per acre per year. Findings suggest that current shrimp production and shrimp price will no longer be optimal once the external costs are internalized. Thus alternative policy recommendations have been proposed so that shrimp farming becomes a sustainable and equitable means of aquaculture.Comment: 28 page

Does Use of Twitter by Political Leaders Matter in a Health Crisis? The Perspective of COVID-19

While extant literature has reached a consensus on the effectiveness of Twitter in crisis communication, this paper contextualizes the use of Twitter specifically by political leaders during the COVID-19 crisis. We first identify political leaders on Twitter using machine learning techniques and then examine the significant properties of their networks. The findings demonstrate that the network of political leaders on Twitter is relatively dense and well-connected. However, a few nodes are highly prominent and have a large number of connections. Our study detects twenty-three communities of political leaders and observes the evidence of political polarization in the network. We also find two large communities representing the Republican and Democratic parties at the national-level. The remaining communities are reasonably well-balanced in size and center at the state-level. In further analysis, we plan to investigate the patterns of COVID-19 crisis communications through this network and explore the association with COVID-19 outcomes using panel data

Managing Engagement in an Emerging Economy Service

© 2019, Emerald Publishing Limited. Purpose: The purpose of this paper is to offer a better understanding of managing engagement in an emerging economy service. It explores the role of organisational climates for initiative and psychological safety as the key drivers of employee engagement (EE). It also examines the effects of EE on customer engagement (CE) and, in turn, on relationship commitment and switching intention. Design/methodology/approach: Data were collected through a structured survey of service employees and customers of 69 bank branches in Bangladesh using two survey instruments. Responses were collected from 156 employees and 316 customers. A dyadic data set was created by matching customer data with the corresponding employee data collected from each bank branch. Structural equation modelling using AMOS (version 22.0) was employed for data analysis. Findings: Organisational climates for initiative and psychological safety positively influence EE. In turn, EE significantly influences CE which has a significant impact on customer relationship commitment and switching intention. Research limitations/implications: Future research could consider actual customer behaviour, such as repeat purchase, as the key outcome variable. Practical implications: The findings emphasise that investment by service managers in organisational resources to facilitate favourable climates for initiative and psychological safety would engage employees at work, which would ultimately help to attain CE and commitment, and reduce switching intention. Originality/value: This research extends the existing engagement literature with empirical evidence supporting two new EE drivers and two new CE outcomes. It offers a better understanding of managing engagement in the financial services industry of an emerging economy, focussing on the relationship chain from organisational climate to EE, CE and customer-based outcomes

An mHealth Application to Promote Diabetes Self-care Behavior among Medically Underserved Population

Diabetes is a chronic illness that causes serious health complications such as kidney failure, limb amputations, and often leads to premature death. Adoption of self-care behavior among diabetes patients is known to improve their health conditions and quality of life. Medically underserved populations (MUP) are disproportionately affected by diabetes. In this research we use a design science approach to develop an mHealth app to promote diabetes self-care behavior among MUPs. Using design theories on behavior change and user-centered design we articulated five key design principles. A mobile app based on these principles and AADE7 self-care behavior framework has been implemented using an Android system. We are currently in the process of evaluating its effectiveness. Our research contributes to the discourse on design for behavior change and illustrates the effectiveness of mHealth apps in promoting healthy lifestyles

Compact Wrench-Shaped Resonator Loaded UWB Antenna with Notched Frequency Characteristics

In the manuscript, the design of a wrench-shaped resonator loaded ultra-wideband (UWB) antenna has been proposed using notched frequency characteristics. The antenna is composed of the patch with microstrip feed line, a wrench-shaped resonator, and a slotted partial ground plane. A notched frequency is created due to the electromagnetic coupling of wrench-shaped resonator. In order to observe the effects of wrench-shaped resonator, a parametric study has been executed. Measured results are compared with simulations (with and without notched bands) and a stable similarity has been observed. The surface current, radiation patterns and the impedance (imaginary and real) have ensured the compression of wanted notched frequency band

New NRI Metamaterial for Multi-band Operation

A new negative refractive index (NRI) metamaterial unit cell is presented in this study. The negative refractive index property is being displayed by the unit cell of metamaterial in the four distinct microwave frequency bands. Finite integration technique was adopted to evaluate the property of the material. More than 1 GHz bandwidth region was found exhibiting NRI property for the material in the microwave spectra

Prevalence and risk factors of childhood anemia in Nepal: A multilevel analysis

Introduction Anemia is a common problem in children particularly in developing countries and taking steps to tackle it is one of the major public health challenges for Nepal. The objective of this study is to investigate the prevalence of individual, household and community level determinants of childhood anemia in Nepal. Methods Data was taken from a nationally representative sample of 1,942 Nepalese children aged from 6–59 months. The Chi-square test was used to determine the bivariate relationship between the selected variables and childhood anemia and a multilevel logistic regression model with a random intercept at household and community level was used to identify important determinants of this kind of anemia. Results The results showed that 52.6% (95% CI: 49.8%-55.4%) of the children were anemic while 26.6% (95% CI: 24.0%-29.3%) of them were moderate to severe. The prevalence of overall anemia was higher among children aged less than 11 months as well as in underweight children, children of underweight, anemic and uneducated mothers and those in the terrain ecological regions. Multivariable analysis showed that children aged less than 11 months, who were underweight and had anemic mothers were more likely to have moderate or severe anemia. Children in the hilly ecological region were less likely to have it compared to mountain and terrain ecological regions. Children in middle-class families and children of mothers who completed secondary education were more likely to have anemia. Conclusion Nepal is facing a serious public health problem due to the high prevalence of childhood anemia. This adverse situation occurs due to socio-demographic and geographical factors such as age, malnutrition status, mother’s anemia status, socio-economic status and regional variations. Prevention of childhood anemia should be given top priority in Nepal and should be considered as a major public health intervention

A Diamond Shaped Multilevel Inverter With Dual Mode of Operation

This study presents a novel multilevel inverter structure that can operate in both switched capacitor and asymmetric DC source modes. In the first mode, it can produce seven-level output voltage employing two switched capacitors and one single DC supply. The five-level output voltage is produced while operating the second mode. The voltage ratio between the input and output voltage for the capacitor mode is 1:3 (triple voltage gain). During the first mode, the capacitor of the inverter is self -balanced whereas the inverter can produce higher voltage output in the DC source mode. The proposed inverter reduces the total standing voltage in both modes of operations as it can generate the output voltage without requiring any additional H-bridge circuit. The feasibility and predominate features of the proposed inverter have been established by comparing with existing topologies in terms of power components count. Results obtained from this study are validated using simulation employing sinusoidal pulse width modulation (SPWM). A hardware prototype has also been developed for further validation