Matching Items (224)
Description
The Kasturba Gandhi Balika Vidyalaya (KGBV) policy scheme launched in 2004 by the Ministry of Human Resource Development, the Government of India, aims to provide secondary level education (grade 6-8) for girls residing predominantly in minority communities, the Scheduled Caste (SC), the Scheduled Tribe (ST), and the Other Backward Caste (OBC). Since its launch, the Government of India established 2,578 KGBV schools in 27 states and union territories (UTs). The present study examines the new policy and its implementation at three KGBV schools located in rural villages of Uttar Pradesh (UP), India. The purpose was to analyze the Government of India's approach to increasing education opportunity and participation for educationally disadvantaged girls using the empowerment framework developed by Deepa Narayan. Observations at three schools, interviews with teachers and staff members of the implementation agency (i.e., Mahila Samakhya (MS)), and surveys administered to 139 teachers were conducted over a four month period in 2009. Adopting creative teaching approaches and learning activities, MS creates safe learning community which is appropriate for the rural girls. MS gives special attention to nurturing the girls' potential and empowering them inside and outside the school environment through social discussion, parental involvement, rigid discipline and structure, health and hygiene education, and physical and mental training. Interviews with the state program director and coordinators identified some conflicts within government policy schemes such as the Teacher-pupil ratios guidelines as a part of the programs for the universalization of elementary education. Major challenges include a high turnover rate of teachers, a lack of female teachers, a lack of provision after Class 8, and inadequate budget for medical treatment. Recommendations include promoting active involvement of male members in the process of girls' empowerment, making MS approaches of girls' education in rural settings standardized for wider dissemination, and developing flexible and strong partnership among local agencies and government organizations for effective service delivery.
ContributorsWatanabe, Miku (Author) / Fischman, Gustavo (Thesis advisor) / Wiley, Terrence (Committee member) / Mccarty, Teresa (Committee member) / Arizona State University (Publisher)
Created2011
Description
There will always be a need for high current/voltage transistors. A transistor that has the ability to be both or either of these things is the silicon metal-silicon field effect transistor (MESFET). An additional perk that silicon MESFET transistors have is the ability to be integrated into the standard silicon on insulator (SOI) complementary metal oxide semiconductor (CMOS) process flow. This makes a silicon MESFET transistor a very valuable device for use in any standard CMOS circuit that may usually need a separate integrated circuit (IC) in order to switch power on or from a high current/voltage because it allows this function to be performed with a single chip thereby cutting costs. The ability for the MESFET to cost effectively satisfy the needs of this any many other high current/voltage device application markets is what drives the study of MESFET optimization. Silicon MESFETs that are integrated into standard SOI CMOS processes often receive dopings during fabrication that would not ideally be there in a process made exclusively for MESFETs. Since these remnants of SOI CMOS processing effect the operation of a MESFET device, their effect can be seen in the current-voltage characteristics of a measured MESFET device. Device simulations are done and compared to measured silicon MESFET data in order to deduce the cause and effect of many of these SOI CMOS remnants. MESFET devices can be made in both fully depleted (FD) and partially depleted (PD) SOI CMOS technologies. Device simulations are used to do a comparison of FD and PD MESFETs in order to show the advantages and disadvantages of MESFETs fabricated in different technologies. It is shown that PD MESFET have the highest current per area capability. Since the PD MESFET is shown to have the highest current capability, a layout optimization method to further increase the current per area capability of the PD silicon MESFET is presented, derived, and proven to a first order.
ContributorsSochacki, John (Author) / Thornton, Trevor J (Thesis advisor) / Schroder, Dieter (Committee member) / Vasileska, Dragica (Committee member) / Goryll, Michael (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT The purpose of this study is to demonstrate that stable lipid bilayers can be set up on an array of silicon micropores and can be used as sites for self-inserting ion-channel proteins which can be studied independently of each other. In course of this study an acrylic based holder was designed and machined to ensure leak-free fluidic access to the silicon micropores and physical isolation of the individual array channels. To measure the ion-channel currents, we simulated, designed and manufactured low-noise transimpedance amplifiers and support circuits based on published patch clamp amplifier designs, using currently available surface-mount components. This was done in order to achieve a reduction in size and costs as well as isolation of individual channels without the need for multiplexing of the input. During the experiments performed, stable bilayers were formed across an array of four vertically mounted 30 µm silicon micropores and OmpF porins were added for self insertion in each of the bilayers. To further demonstrate the independence of these bilayer recording sites, the antibiotic Ampicillin (2.5 mM) was added to one of the fluidic wells. The ionic current in each of the wells was recorded simultaneously. Sub-conductance states of Ompf porin were observed in two of the measurement sites. In addition, the conductance steps in the site containing the antibiotic could be clearly seen to be larger compared to those of the unmodified site. This is due to the transient blocking of ion flow through the porin due to translocation of the antibiotic. Based on this demonstration, ion-channel array reconstitution is a potential method for efficient electrophysiological characterization of different types of ion-channels simultaneously as well as for studying membrane permeation processes.
ContributorsRamakrishnan, Shankar (Author) / Goryll, Michael (Thesis advisor) / Thornton, Trevor J (Committee member) / Blain Christen, Jennifer M (Committee member) / Arizona State University (Publisher)
Created2011
Description
In the last few years, significant advances in nanofabrication have allowed tailoring of structures and materials at a molecular level enabling nanofabrication with precise control of dimensions and organization at molecular length scales, a development leading to significant advances in nanoscale systems. Although, the direction of progress seems to follow the path of microelectronics, the fundamental physics in a nanoscale system changes more rapidly compared to microelectronics, as the size scale is decreased. The changes in length, area, and volume ratios due to reduction in size alter the relative influence of various physical effects determining the overall operation of a system in unexpected ways. One such category of nanofluidic structures demonstrating unique ionic and molecular transport characteristics are nanopores. Nanopores derive their unique transport characteristics from the electrostatic interaction of nanopore surface charge with aqueous ionic solutions. In this doctoral research cylindrical nanopores, in single and array configuration, were fabricated in silicon-on-insulator (SOI) using a combination of electron beam lithography (EBL) and reactive ion etching (RIE). The fabrication method presented is compatible with standard semiconductor foundries and allows fabrication of nanopores with desired geometries and precise dimensional control, providing near ideal and isolated physical modeling systems to study ion transport at the nanometer level. Ion transport through nanopores was characterized by measuring ionic conductances of arrays of nanopores of various diameters for a wide range of concentration of aqueous hydrochloric acid (HCl) ionic solutions. Measured ionic conductances demonstrated two distinct regimes based on surface charge interactions at low ionic concentrations and nanopore geometry at high ionic concentrations. Field effect modulation of ion transport through nanopore arrays, in a fashion similar to semiconductor transistors, was also studied. Using ionic conductance measurements, it was shown that the concentration of ions in the nanopore volume was significantly changed when a gate voltage on nanopore arrays was applied, hence controlling their transport. Based on the ion transport results, single nanopores were used to demonstrate their application as nanoscale particle counters by using polystyrene nanobeads, monodispersed in aqueous HCl solutions of different molarities. Effects of field effect modulation on particle transition events were also demonstrated.
ContributorsJoshi, Punarvasu (Author) / Thornton, Trevor J (Thesis advisor) / Goryll, Michael (Thesis advisor) / Spanias, Andreas (Committee member) / Saraniti, Marco (Committee member) / Arizona State University (Publisher)
Created2011
Description
The theme for this work is the development of fast numerical algorithms for sparse optimization as well as their applications in medical imaging and source localization using sensor array processing. Due to the recently proposed theory of Compressive Sensing (CS), the $\ell_1$ minimization problem attracts more attention for its ability to exploit sparsity. Traditional interior point methods encounter difficulties in computation for solving the CS applications. In the first part of this work, a fast algorithm based on the augmented Lagrangian method for solving the large-scale TV-$\ell_1$ regularized inverse problem is proposed. Specifically, by taking advantage of the separable structure, the original problem can be approximated via the sum of a series of simple functions with closed form solutions. A preconditioner for solving the block Toeplitz with Toeplitz block (BTTB) linear system is proposed to accelerate the computation. An in-depth discussion on the rate of convergence and the optimal parameter selection criteria is given. Numerical experiments are used to test the performance and the robustness of the proposed algorithm to a wide range of parameter values. Applications of the algorithm in magnetic resonance (MR) imaging and a comparison with other existing methods are included. The second part of this work is the application of the TV-$\ell_1$ model in source localization using sensor arrays. The array output is reformulated into a sparse waveform via an over-complete basis and study the $\ell_p$-norm properties in detecting the sparsity. An algorithm is proposed for minimizing a non-convex problem. According to the results of numerical experiments, the proposed algorithm with the aid of the $\ell_p$-norm can resolve closely distributed sources with higher accuracy than other existing methods.
ContributorsShen, Wei (Author) / Mittlemann, Hans D (Thesis advisor) / Renaut, Rosemary A. (Committee member) / Jackiewicz, Zdzislaw (Committee member) / Gelb, Anne (Committee member) / Ringhofer, Christian (Committee member) / Arizona State University (Publisher)
Created2011
Description
In this dissertation I present data gathered from an eleven-month qualitative research study with adolescents living and working on the streets of Lima, Peru. Through the pairing of photovoice with participant observations, this work incorporates distinctive methodological and theoretical viewpoints in order to complicate prevailing understandings of street life. In this dissertation, I examine the identities that children and adolescents on the street develop in context, and the ways in which photography can be a useful tool in understanding identity development among this population. Through a framework integrating theories of identity and identity performance with spatial theories, I outline how identity development among children and adolescents living on the street is directly connected to their relationships with the urban landscape and the outreach organizations that serve them. The organizations and institutions that surround children on the street shape who they are, how they are perceived by society, and how they view and understand themselves in context. It is through the interaction with aid organizations and the urban landscape that a street identity is learned and developed. Furthermore, as organizations, children and adolescents come together within the context of the city, a unique street space is created. I argue that identity and agency are directly tied to this space. I also present the street as a thirdspace of possibility, where children and adolescents are able to act out various aspects of the self that they would be unable to pursue otherwise. Weaved throughout this dissertation are non-traditional writing forms including narrative and critical personal narrative addressing my own experiences conducting this research, my impact on the research context, and how I understand the data gathered.
ContributorsJoanou, Jamie Patrice (Author) / Swadener, Beth B. (Thesis advisor) / Margolis, Eric (Committee member) / Arzubiaga, Angela (Committee member) / Fischman, Gustavo (Committee member) / Arizona State University (Publisher)
Created2011
Description
The Civil Rights Project estimates that Black girls are among the least likely to graduate from high school. More specifically, only about half, or 56%, of freshman Black girls graduate with their class four years later. Beyond the statistics little is known about Black girls who drop out, why they leave school and what happens to them once they are gone. This study is a grounded theory analysis of the stories eight adult Black women told about dropping out of high school with a particular focus on how dropping out affected their lives as workers, mothers and returners to education. There is one conclusion about dropping out and another about Black female identity. First, the women in my study were adolescents during the 1980s, experienced life at the intersection of Blackness, womaness, and poverty and lived in the harsh conditions of a Black American hyperghetto. Using a synthesis between intersectionality and hyperghettoization I found that the women were so determined to improve their economic and personal conditions that they took on occupations that seemed to promise freedom, wealth and safety. Because they were so focused on their new lives, their school attendance suffered as a consequence. In the second conclusion I argued that Black women draw their insights about Black female identity from two competing sources. The two sources are their lived experience and popular controlling images of Black female identity.
ContributorsGriffin, Erica Nicole (Author) / Powers, Jeanne (Thesis advisor) / Fischman, Gustavo (Committee member) / Margolis, Eric (Committee member) / Arizona State University (Publisher)
Created2011
Description
In very small electronic devices the alternate capture and emission of carriers at an individual defect site located at the interface of Si:SiO2 of a MOSFET generates discrete switching in the device conductance referred to as a random telegraph signal (RTS) or random telegraph noise (RTN). In this research work, the integration of random defects positioned across the channel at the Si:SiO2 interface from source end to the drain end in the presence of different random dopant distributions are used to conduct Ensemble Monte-Carlo ( EMC ) based numerical simulation of key device performance metrics for 45 nm gate length MOSFET device. The two main performance parameters that affect RTS based reliability measurements are percentage change in threshold voltage and percentage change in drain current fluctuation in the saturation region. It has been observed as a result of the simulation that changes in both and values moderately decrease as the defect position is gradually moved from source end to the drain end of the channel. Precise analytical device physics based model needs to be developed to explain and assess the EMC simulation based higher VT fluctuations as experienced for trap positions at the source side. A new analytical model has been developed that simultaneously takes account of dopant number variations in the channel and depletion region underneath and carrier mobility fluctuations resulting from fluctuations in surface potential barriers. Comparisons of this new analytical model along with existing analytical models are shown to correlate with 3D EMC simulation based model for assessment of VT fluctuations percentage induced by a single interface trap. With scaling of devices beyond 32 nm node, halo doping at the source and drain are routinely incorporated to combat the threshold voltage roll-off that takes place with effective channel length reduction. As a final study on this regard, 3D EMC simulation method based computations of threshold voltage fluctuations have been performed for varying source and drain halo pocket length to illustrate the threshold voltage fluctuations related reliability problems that have been aggravated by trap positions near the source at the interface compared to conventional 45 nm MOSFET.
ContributorsAshraf, Nabil Shovon (Author) / Vasileska, Dragica (Thesis advisor) / Schroder, Dieter (Committee member) / Goodnick, Stephen (Committee member) / Goryll, Michael (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT Early childhood education (ECE) teacher professional development refers to the various modalities of providing new and or additional content knowledge to the teachers who work with children birth to five. The purpose of this study was to examine the effectiveness of an Arizona United Way-administered intervention project designed to provide focused professional development activities to 15 ECE teachers at seven high-need, center-based early care and education settings. Specifically, this study determined if these interventions influenced the teachers to undertake formative career path changes such as college coursework. In addition, the study also sought to understand the views, beliefs, and attitudes of these ECE teachers and if/how their perspectives influenced their educational career paths. Data were gathered through the triangulated use of participants' responses to a survey, face-to-face interviews, and a focus group. Findings demonstrate that the teachers understand that professional development, such as college coursework, can increase a person's knowledge on a given topic or field of study, but that they feel qualified to be a teacher for children birth to five even though 12 of the 15 teachers do not hold an AA/AAS or BA/BS degree in any area of study. Further, the teachers suggested that if they were to earn a degree it would most likely be in another field of study beside education. These responses provide another reason professional development efforts to encourage ECE teachers to seek degrees in the field of education may be failing. If ECE teachers wanted to invest time, energy and funds they would acquire a degree, which provided more financial reward and professional respect.
ContributorsOrtiz, Karen J. (Karen Jean) (Author) / Kelley, Michael F. (Thesis advisor) / Enz, Billie J. (Thesis advisor) / Romero, Mary (Committee member) / Fischman, Gustavo (Committee member) / Arizona State University (Publisher)
Created2011
Description
The past two decades have been monumental in the advancement of microchips designed for a diverse range of medical applications and bio-analysis. Owing to the remarkable progress in micro-fabrication technology, complex chemical and electro-mechanical features can now be integrated into chip-scale devices for use in biosensing and physiological measurements. Some of these devices have made enormous contributions in the study of complex biochemical processes occurring at the molecular and cellular levels while others overcame the challenges of replicating various functions of human organs as implant systems. This thesis presents test data and analysis of two such systems. First, an ISFET based pH sensor is characterized for its performance in a continuous pH monitoring application. Many of the basic properties of ISFETs including I-V characteristics, pH sensitivity and more importantly, its long term drift behavior have been investigated. A new theory based on frequent switching of electric field across the gate oxide to decrease the rate of current drift has been successfully implemented with the help of an automated data acquisition and switching system. The system was further tested for a range of duty cycles in order to accurately determine the minimum length of time required to fully reset the drift. Second, a microfluidic based vestibular implant system was tested for its underlying characteristics as a light sensor. A computer controlled tilt platform was then implemented to further test its sensitivity to inclinations and thus it‟s more important role as a tilt sensor. The sensor operates through means of optoelectronics and relies on the signals generated from photodiode arrays as a result of light being incident on them. ISFET results show a significant drop in the overall drift and good linear characteristics. The drift was seen to reset at less than an hour. The photodiodes show ideal I-V comparison between photoconductive and photovoltaic modes of operation with maximum responsivity at 400nm and a shunt resistance of 394 MΩ. Additionally, post-processing of the tilt sensor to incorporate the sensing fluids is outlined. Based on several test and fabrication results, a possible method of sealing the open cavity of the chip using a UV curable epoxy has been discussed.
ContributorsMamun, Samiha (Author) / Christen, Jennifer Blain (Thesis advisor) / Goryll, Michael (Committee member) / Yu, Hongyu (Committee member) / Arizona State University (Publisher)
Created2011