Multiple Ssid Framework for RSS-Fingerprint Based Indoor Positioning Systems

Abed, Ahmed Western Michigan University ProQuest Dissertations 2019 해외박사(DDOD)

Location-Based Indoor positioning systems significance stems from the bloom of recent applications in various fields such as in tracking services for an elder or a patient within large living communities, mobile robot localization, and several other security applications. Currently, Global Positioning Systems (GPS) are the most widely used location-sensing technique. However, satellite-based GPS signals require line of sight (LOS) to work correctly, which is something cannot be achieved inside buildings. Fortunately, wireless LAN can be employed in indoor positioning systems (IPS), and since all large buildings such as malls, hospitals, airports, schools, and museums have hundreds of Wi-Fi access points, it can provide accurate IPS without any additional infrastructure. Of special significance, the Wi-Fi fingerprinting-based techniques that offer a much less complex when compared to other methods such as the angle of arrival (AOA) and time difference of arrival (TDOA). Wi-Fi fingerprinting-based techniques use the received signal strength (RSS) to build radio maps. However, RSS value is a function of the distance between the Mobile System (MS) and Access Point (AP), which varies due to the multipath propagation phenomenon and human body blockage. Furthermore, fingerprinting approaches have several disadvantages such as labor, computational cost, and diversity (in signals and environment). In this dissertation, a novel approach that uses Multiple Service Set Identifiers (MSSID) to tackle these challenges is presented. MSSID means each AP can be configured to transmit N signals instead of one signal, to serve different clients’ categories simultaneously. IPS MSSID-based framework using three different realizations is proposed, implemented, and verified inside the College of Engineering and Applied Sciences (CEAS) building at Western Michigan University.First, a MSSID Probabilistic Neural Network (PNN)-based multi-classifier is proposed with a spatial voting scheme as a tool to determine the location of the user. Spatial voting is designed specifically to tackle the negative impact of multi-path propagation. The performance of the proposed system compared to some of the conventional methods such as K-Nearest Neighbors (K-NN) and multi-class support vector machine (SVM). Experimental results show that spatial voting of three PNN classifiers can significantly mitigate the adverse effects of RSS variation. The precision of the proposed system for PNN and K-NN at distance error of 2m is 90% and 85%, respectively. As a comparison to the proposed systems, the precision of the traditional techniques for PNN and K-NN is 82% and 78%, respectively. In addition, the experimental results show that the average distance error for PNN-based proposed system is less than 0.73 m when the length of AP (L) is 18. Furthermore, the distance error of proposed system shows high stability where it has lowest standard deviation as compared with other traditional techniques.Second, an MSSID-based adaptive K-nearest neighbor (K-NN) is proposed to tackle the challenges associated with static K-NN based-systems. The K-nearest neighbors (KNN) is selected for its significant performance with ease of realization. However, the static nature of K-NN, that is, in using a constant number of the nearest neighbors, leads to a serious shortcoming in its accuracy. In addition, the nature of the RSS-IPS challenges such as fading due to the multipath of electromagnetic waves inside buildings would mislead the solution of nearest neighbors. These reasons often result in lower perform than expected because of the increase in the distant neighbors’ biasing error. In this part, we address these challenges by proposing a new method based on multiple services set identifiers (MSSID) to select adaptively the appropriate nearest neighbors, and reject undesired ones. The ensemble technique is utilized to enhance the performance by combining the outputs of three adaptive K-NN estimators. The experimental results demonstrate the superiority of the adaptive K-NN based-proposed system over static KNN. The results show that the precision of the proposed system for the adaptive K-NN at distance error of 2m is 73%, and the average distance error is less than 1.3 m. As a comparison to the proposed systems, the precision of the traditional K-NN at distance error of 2m is 61%, and the average distance error is 1.85 m.Third, an MSSID- based particle swarm optimization (PSO) system is proposed. PSO technique is designed to select the most informative APs at each clustered area and combined with the K-means clustering method to confine location of the user into a smaller area and thus enhance positioning accuracy. WLAN-fingerprint based methods require recording RSS data of the surrounding APs, which results in including much more than the needed number of APs. Therefore, eliminating redundant or non-informative APs not only reduces the computational cost but also improves performance accuracy. At each cluster, PSO is applied to select the best joint combination of APs decided by the minimum mean of distance error. The results show that the proposed system outperforms other commonly proposed selection methods such as random, strongest APs, and Fisher criterion. Moreover, with reduction of 68% AP vector’s length (L=11), the results report that the proposed system achieves a positioning accuracy of 0.85 m over 3000 m2, with an accumulative density function (CDF) of 88% with a distance error of 2 m.The use of the multiple SSID technique supports IPS classifiers and produces higher precision than with single SSID. The proposed algorithms show a notable improvement over its counterpart with single SSID along with the distance error and reduction of RSS-vector’s length.

High school seniors' perceptions of career and technical education and factors influencing their decision to attend an area career technical center

Gaunt, David P Western Michigan University 2005 해외박사(DDOD)

This study explored the profile of CTE students with regard to their academic standing and their socioeconomic background, examined high school seniors' perceptions of career and technical education, and identified the people and other factors that influence students in their decision-making about CTE enrollment. A 29-question survey was administered to 451 seniors from seven public high schools served by the Wexford-Missaukee Area Career Technical Center, operated by an intermediate school district in northern lower Michigan. Significant findings indicate that the typical profile of CTE students with respect to socioeconomic status and academic standing would identify a CTE student as performing somewhat lower academically, living less often with both parents while more commonly residing without either parent present, and being more economically disadvantaged than their non-CTE counterparts. While more CTE students than non-CTE students perceive the Career Technical Center as an avenue to college, both groups identify strongly with the CTE connection to the workplace. Even more significantly, both groups strongly perceive that the Career Technical Center addresses the needs of students from all ability levels. The most influential people upon a student regarding a decision to attend, or not to attend, a CTE program, are friends and parents. CTE staff and high school counselors also play a fairly significant role in influencing CTE students to attend. Spending half of the day away from the high school is the most significant factor in influencing CTE students to attend. The opportunity for students to see the area center firsthand, and the opportunity to receive college credit, were also significant influencing factors.

The practice of continuous improvement in higher education

Thalner, Deborah M Western Michigan University 2005 해외박사(DDOD)

Studies on the use of Total Quality Management (TQM) within higher education have primarily focused on the implementation of TQM as an institutional initiative. While TQM has been successful in business and industry and has seen some limited success in higher education, the most recent studies on its use in higher education indicate that it has not been successful institution-wide, and in many cases has been abandoned after two to three years. The problem, therefore, is one of a perceived need for continuous improvement in coupled with mixed results from previous attempts at implementation. This research study focused on higher education's use of continuous improvement methods; however, the focus was on specific departmental initiatives, rather than on institution-wide implementation. This study surveyed directors in departments of Financial Services, Facilities Management, Auxiliary Services, and Corporate Training within all public higher education institutions in Michigan. Out of a population of 148 directors surveyed, 54% responded to the survey. Directors of these departments were sent an e-mail with a link to a web-based survey. In addition to determining the level of continuous quality improvement (CQI) use in these departments, the survey also identified common drivers, obstacles, support factors, and outcomes derived from CQI. Key findings included that most had attempted CQI methods at some point in time and continued to pursue CQI. They were able to achieve the outcomes of improved service, quicker response, improved efficiencies, and increased financial returns, while at the same time seeing improved communications within their department and with the institution. These improvements could be realized regardless of institution type, department type, or type of CQI method used, and in spite of the obstacles encountered. In summary, TQM purists would suggest that TQM/CQI is no longer in place within higher education institutions as there is limited evidence of institution-wide continuing implementation. This study revealed, however, that department-based implementation is still in effect, and these departments continue to use CQI methods beyond the time period that current literature suggests it takes for higher education institutions to abandon CQI.

(A)study of instructor grading philosophies and practices in undergraduate courses at Western Michigan University

오은경 Western Michigan University 1976 국내박사

The effects of the Michigan Transition Outcomes Project

Finn, Jane E Western Michigan University 2005 해외박사(DDOD)

This study investigated whether the Transition Outcomes Project used in Michigan resulted in improved compliance with the transition components required by the Individuals with Disabilities Education Act of 1997 (IDEA 1997) and interviewed staff who have implemented this model to identify their perceptions of how it affected the transition planning process for students with disabilities. The study used qualitative and quantitative measures. The quantitative measures studied the effectiveness of the model, while the qualitative measures investigated the perceptions of the school personnel who implemented the model in their district. Findings showed that the Michigan Transition Outcomes Project is an effective model for improving compliance with IDEA transition components. The key contact personnel interviewed reported that the model had three major positive effects: greater understanding of IDEA's transition requirements, enhancement of students' participation in the planning process, and improved interagency and interdisciplinary collaboration. Outcomes consisted of better focused transition meetings, improved perceptions concerning the ability of students with disabilities, more parent participation at meetings, and improved compliance. Results also showed that "best practices" in transition were implemented, including formal and informal assessments, life skills instruction, and staff training on transition components. The results of this study extend the research on how to improve compliance with the IDEA transition components, and provide valuable information about the perceptions of the participants who used the model.

A study of emergent leadership factors in a Total Ministry model

Meyers, David C Western Michigan University 2001 해외박사(DDOD)

This study generalized emergent leadership research to the unstudied population of Total Ministry parishes in the Episcopal Church. The research population was 75 small congregations who chose parish members as their liturgical and pastoral leaders. A survey was designed to distinguish more satisfied from less satisfied parishes in areas of worship, climate, and pastoral care. Each group was given a questionnaire with 29 emergent leadership factors. It was hypothesized that more satisfied parishes would match the constructs of emergent leadership to a higher degree. A T-test was used to compare scores. Results were very strong in pastoral care and climate, indicating that emergent leadership principals can be generalized to the study group in those areas. The area of worship was less closely aligned with the hypotheses. Peculiarities responsible for the discrepancy suggested that qualifications for a priest of the church may not represent those of a typical emergent leader.

Teacher quality and teacher preparedness in public secondary schools: Evidence from SASS 1999--2000

Lu, Xuejin Western Michigan University 2005 해외박사(DDOD)

In this study, I inquired into the quality of public secondary school teachers by examining what percentages of teachers were highly qualified in the fields of their main teaching assignment and in each specific field they taught. The focus was placed on the core academic fields (English, social studies, math, and science) and the subfields of science (chemistry, physics, earth science, and physical science). I also investigated whether there were possible variations in the distribution of highly qualified teachers by school locations and by the percentages of minority student enrollment in schools. Furthermore, I examined the relationship between the quality of new secondary school teachers and their perceptions on their preparation for teaching. In this study, a highly qualified teacher had the following characteristics: holding at least a bachelor's degree, a full state certification, and an undergraduate or graduate major in the subject taught. I analyzed data extracted from the 1999-2000 Schools and Staffing Survey (SASS) for public school teachers. Descriptive statistics was used to identify the percentages of highly qualified teachers in the subjects taught. Chi-Square tests were employed to examine the distribution of highly qualified teachers. Multivariate analysis of variance was used to determine the relationship between the quality of new teachers and their perceptions on their preparedness. Results revealed that the percentages of highly qualified teachers in the core academic fields, especially in the subfields of science, were far from satisfactory. Overall more than one-forth of the teachers were not highly qualified in their main assignment fields. Teachers who were not highly qualified in the subfields of science were found with a range from 52 percent to 84 percent. Urban schools and schools with a higher percentage of minority students were much less likely to have highly qualified teachers. New teachers who were highly qualified in the subject taught felt better prepared than those who were not highly qualified. The findings suggest that the situation of teacher quality in secondary schools is posing a serious challenge for implementing the NCLB's mandate of highly qualified teachers by 2006. Furthermore, the findings seem to raise an equity issue in staffing schools.

Structure preserving algorithms for computing the symplectic singular value decomposition

Chaiyakarn, Archara Western Michigan University 2005 해외박사(DDOD)

In this thesis we develop two types of structure preserving Jacobi algorithms for computing the symplectic singular value decomposition of real symplectic matrices and complex symplectic matrices. Unlike general purpose algorithms, these algorithms produce symplectic structure in all factors of the singular value decomposition. Our first algorithm uses the relation between the singular value decomposition and the polar decomposition to reduce the problem of finding the symplectic singular value decomposition to that of calculating the structured spectral de composition of a doubly structured matrix. A Jacobi-like method is developed to compute this doubly structured spectral decomposition. The second algorithm is a one-sided Jacobi method that directly computes the structured singular value decomposition of real or complex symplectic matrices. Numerical experiments show that our algorithms converge quadratically. Furthermore, the number of sweeps needed for convergence is favorable when compared to Jacobi-like algorithms for other structured matrices.

Global optimality conditions in mathematical programming and optimal control

Pacheenburawana, Pariwat Western Michigan University 2005 해외박사(DDOD)

We derive new first-order necessary and sufficient optimality conditions characterizing global minimizers in mathematical programming and optimal control problems. These conditions are based on level sets of an objective functional and they do not assume special structure of a problem (convexity, linearity, etc.). For a mathematical programming problem of minimization of a smooth functional on some compact convex set with equality nonlinear constraints, we derive first-order optimality conditions in the form of a generalized Lagrange multiplier rule. This rule should hold for any point from the level set of the objective functional corresponding to a global minimizer. We demonstrate that these necessary conditions become sufficient ones for optimality under additional assumption of non-degeneracy of the Lagrange multiplier rule. We also study global optimality conditions for free time optimal control problem which includes the classical minimum-time problem. We derive necessary conditions for global optimality of relaxed controls in terms of Pontryagin minimum principle for any relaxed control from the level set of the objective functional. It is shown that these optimality conditions are sufficient for global optimality if the minimum principle is non-degenerated at least at one point on a time interval. In particular, we derive that if some relaxed control satisfies non-degenerated Pontryagin minimum principle and there is no other relaxed controls with the same value of the objective functional, then this relaxed control is globally optimal. Finally, we demonstrate that for some generic class of free time optimal control problems for almost all initial points there exists a unique optimal control satisfying the non-degenerated minimum principle. This implies that for such problems our sufficient global optimality conditions can be applied for almost all initial points.

Bufadienolides in the chemical defenses of the toads, Bufo americanus and Bufo fowleri

Merovich, Catherine E Western Michigan University 2005 해외박사(DDOD)

I investigated the steroidal chemical defenses (bufadienolides) of Bufo americanus and Bufo fowleri. By the nature of their complex, biphasic life cycles, toads, like other amphibians are important components of aquatic and terrestrial habitats and are prey to numerous invertebrates and vertebrates. Bufadienolides are presumed to be important anti-predatory compounds although much of their chemical ecology is poorly understood. I investigated (1) ontogenetic variation in bufadienolides, (2) bufadienolides from adult parotoid secretion, (3) effectiveness of bufadienolides against a terrestrial predator, and (4) effectiveness of bufadienolides against an aquatic predator. I hypothesized that B. americanus would have a more extensive bufadienolide profile and a more effective suite of chemical defenses than B. fowleri and that this could account for distributional differences in these toads. Results showed variability in numbers and concentrations of bufadienolides among toad developmental stages, but cumulatively no difference in total mean concentrations. Bufadienolide concentrations across developmental stages appeared to fit Brodie and Formanowicz's (1987) model, but were more pronounced in eggs. Bufadienolides did not appear to be inducible following metamorphosis. More bufadienolides were detected in adult B. americanus but their mean total concentrations were not larger than in B. fowleri suggesting that distributional differences might be explained by variation in bufadienolide types rather than by bufadienolide concentrations. However, seven bufadienolides were statistically different between toad species. In B. americanus there was much overlap in bufadienolide types and concentrations from all collection sites. Repeated expressions of parotoid glands revealed highly variable individual responses among toads. In tongue-flick bioassays, terrestrial snake predators responded to chemical stimuli from both B. americanus and B. fowleri with more tongue-flicks and greater tongue-flick attack scores than snakes exposed to distilled water. Because snakes showed elevated tongue-flick rates with parotoid secretions than with toad skin stimuli, parotoid chemicals may present a more concentrated toad stimulant and are not necessarily deterrents to predation. Also, aquatic Dytiscid beetle predators equally consumed both B. americanus and B. fowleri suggesting no discrimination between species or between toad developmental stages.