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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

The relationship between parenting style and epistemological beliefs

Kennell, Brian Lee 12 1900 (has links)
This study explored parenting styles and epistemological beliefs. The purpose was to determine if one’s epistemological beliefs are associated with the parenting style one experiences as a child. Parenting styles were classified as authoritative, authoritarian, indulgent, and neglectful. Epistemological beliefs were classified as certain knowledge, simple knowledge, omniscient authority, quick learning, and innate ability. An ancillary analysis revealed epistemological beliefs and vocabulary knowledge were related to GPA. Sixty-four mostly 17 and 18 year-old students from a medium sized high school in the Midwest completed the Epistemic Beliefs Inventory, a parenting style measure, and a vocabulary measure. Significant differences between parenting styles were found for quick learning, certain knowledge, and omniscient authority. This suggests that the parenting style parents use may impact the formation of the child’s epistemological beliefs. A significant interaction effect was found between vocabulary and quick learning for GPA. This suggests that sophisticated beliefs in quick learning may help a student overcome their low vocabulary knowledge and earn a high GPA. / Thesis (M.Ed.)--Wichita State University, College of Education, Dept, of Counseling, Educational Psychology, and School Psychology / "December 2006."
92

Robust control design of remote catheter insertion mechanism with haptic feedback -- FULL TEXT IS NOT AVAILABLE

Kothari, Chintan Govindbhai 12 1900 (has links)
Robotic surgery is becoming a popular technique for certain procedures since benefits of minimally invasive surgery (MIS) have become general knowledge. However, one of the major shortcomings of the present generation of master-slave robotic systems is the lack of haptic feedback; the surgeon that remotely controls the robot is not able to feel what is happening inside the patient. The objective of this thesis was to design a robust control system for a catheter insertion mechanism for cardiac catheterization with haptic feedback. This thesis is divided into two parts. The first part covers a comprehensive literature review, laboratory setup design and implementation. The second part covers the control aspect and design of a robust control. An H∞ controller was used to achieve system robustness. A new approach to find teleoperation system model for H∞ controller is given. The designed controller was implemented in MATLAB. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering. / "December 2006."
93

Multiterminal Gaussian source coding using pairwise orthogonal transforms

Mahadevaiah, Gowrav Malur 12 1900 (has links)
The multiterminal source coding problem has gained prominence recently due to its relevance to sensor networks. In general, rate-distortion in multiterminal source coding is an open problem. However, variations of multiterminal source coding, such as the chief executive officer problem, are addressed in the literature. In addition, full and partial cooperation among the sensors, and reliability and robustness against sensor failures are also being investigated in the literature. In this thesis, multiterminal Gaussian source coding was investigated in the context of sensor networks. The rate-distortion region was parameterized for a pair of correlated Gaussian sources using an implicit transform parameter. The approach made use of established results in multiple descriptor coding using pairwise orthogonal transforms. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering / "December 2006."
94

Analyze transition state of move rate changes with simulation -- FULL TEXT IS NOT AVAILABLE

Nagabhushana, Keshav Prasad 12 1900 (has links)
In today’s competitive world, on time delivery is one of the most important factors while meeting customer demand. If organizations focus only on the invention and not on value from the customer’s point of view, principles may influence the performance of an organization. On time delivery is expected from organizations to be competitive. This supports research, which will enable to compute various techniques and support them with the organization’s premeditated and equipped plan. This thesis proposes a method that will analyze the transition state of move rate changes in a simulation model for an aircraft assembly plant. In order to analyze the results, the entire thesis was divided into two major sections. In the first section, a real case study was considered to develop a simulation model to match that of the actual system. After developing the model, the simulation was run for different move rates to capture and analyze the results. The case study dealt with an aircraft assembly plant with various input characteristics. In the case study, the company background was first discussed. The various processes were described in detail. After discussing the background and providing information about the various processes, the simulation model was developed to imitate the actual system. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering / "December 2006."
95

Friction stir welding: thermal effects of a parametric study on butt and lap welds

Naidu, Rajesh B. 12 1900 (has links)
The purpose of this thesis was to develop and validate finite element models of the friction stir welding process for butt and lap welds for specific experimental cases that in effect enhances the predictability of temperature evolution in the joined workpiece. Significant research has been conducted on butt weld thermal process but limited study has been conducted on lap welds. Through examination of several process parameters critical to both weld and lap weld operations insights into process characterization of process parameters could be made. In this study three dimensional finite element heat transfer models using the commercial code LSDYNA were developed to obtain the temperature distribution in the workpiece for two types of welds, namely butt joints and lap joints. For the lap weld model a step function for thermal conductance between sheets was applied to account for varying contact resistance. The developed finite element models were validated with published experimental data. Parametric studies were performed involving both types of welds including process parameters such as tool travel rate and rotational tool velocity for different aluminium alloys. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering. / "December 2006."
96

The effect of unions on work/family benefits

O'Donnell, Joseph B. 12 1900 (has links)
This study seeks to examine the factors that influence work/family benefits. A conceptual model which includes relational, structural, and environmental level factors is proposed to reveal which factors affect the amount of benefits that a company offers. This research uses the National Organizational Survey of 2002. OLS regression analysis indicates strong relationships with Internal Labor market and Unions resulting in statistically significant increases in benefits by 1.526 and .947 respectively. These results indicate the importance of relational level variables on company dynamics. / Thesis (M.A.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Sociology / "December 2006."
97

Design of haptic force feedback for catheter insertion mechanism

Patel, Nikunj Manubhai 12 1900 (has links)
The objective of this thesis is to design a system which can perform catheter insertion into a human body with haptic feedback. The haptic feedback will consist of a system; a surgeon can use to feel forces in his hand while performing operation from a remote distance. The addition of touch sensor will enable the surgeon to know how much force is being applied to any tissues, and he will sense the same feeling as if working on the patient during the manipulation of the catheter. In this research scale model is used to simulate the catheter insertion operation. This research also demonstrates the effectiveness of MR fluid devices in force feedback applications. Force and displacement sensors sense the environment conditions along which the end effectors of electronic actuator moves. This information is then used to control the MR fluid device to provide appropriate force feedback to user. The research done and system created intended for future research benefiting the Wichita State University’s biomechanics program. Suggestions for future research are included. Problems encountered during research and solutions found are also addressed. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "December 2006."
98

Modeling and evaluation of child safety seat and restraint system for aerospace application

Patil, Ashutosh Ashok 12 1900 (has links)
The increasing trend of carrying babies in aircraft raises the question of their safety. The National Transportation Safety Board (NTSB) states that all occupants should be restrained during takeoff, landing, and turbulent conditions and that all infants and small children should be restrained in an approved child restraint system appropriate to their height and weight. The present child seats are primarily developed for automotive applications and not tested for aerospace applications; therefore, there is a need to test these child restraint systems for aerospace test conditions. Also, the cost of actual testing and the secrecy maintained by manufacturers make research process difficult and increase the importance of computer simulations. The need for validated computer models is imperative. The 12-month-old and 3-year-old child seats used in this research have been approved for use in automobiles but not in aircraft. This research attempts to develop and validate a child restraint seat model for aerospace application. Two types of child restraint seat models - 12-month-old and 3-year-old child seat models were developed and validated using the computational tool MADYMO. The surface models of these two types of seat were exported in IGS format and meshed using Hypermesh. The meshed model was then defined as a facet in MADYMO. These models were validated for the type II dynamic test condition specified according to FAA regulations. Validation was carried out by comparing the kinematics in the simulations and the actual sled tests. To ensure validity, a comparison of various acceleration profiles and force/moments experienced by the occupant under test conditions were compared. Furthermore, the injury levels sustained by the occupant in the actual sled tests and the simulations were compared. Thus, the seat models were validated for their practical applications. These simulated models can help in future research on child safety and to generate guidelines for child restraint use in aircraft. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "December 2006."
99

The effect of arm posture and descent height on landing forces

Polsani, Anoop Kumar 12 1900 (has links)
Operators of mobile construction equipment (e.g., bulldozers, scrapers, etc.) often opt to descend out of the cabin in an irregular fashion without using proper egress methods, despite being trained on proper egress methods. The main objective of this research was to quantify and compare the effect of arm posture, landing style, and descent height on ground reaction forces, and acceleration at the ankle and knee by performing a laboratory study. Fifteen male subjects descended from three different descent heights (38.1, 50.8, and 63.5cm) using three different arm postures (arms to the side, arms front, and arms crossed) and landing on both legs at the same time, right leg first, and left leg first. The results demonstrated that with the increase in descent heights, the ground reaction forces, and accelerations at the ankle and knee increased. Landing with the arms out stretched horizontally in front of the body (arms front) resulted in higher ground reaction forces, peak resultant acceleration at the knee, and higher transmissibility between the ankle and the knee compared to the arms hanging to the side of the body. Although having the arms out front when landing may slightly reduce impact forces, this posture may help in maintaining balance upon landing. Landing with “both legs at same time” increased the GRF, whereas landing on one leg first followed by the other leg seemed to distribute the landing force over a longer period of time. Landing on one or two legs at the heights tested in this study resulted in ground reaction forces lower than injury threshold values for the ankle from previous research. However, descending from higher heights may result in impact forces approaching or exceeding injury threshold levels. Results from this study on the effect of arm posture and landing style may be helpful for training OE on egress at lower level heights, however, engineering controls may be needed at higher egress heights. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering / "December 2006."
100

Parametric study of head paths and HIC data for aircraft seat and cabin interior certification

Prabhu, Ghanashyam 12 1900 (has links)
Head Injury is one of the main reasons causing fatalities in air crashes. In the year 2005, of the total 3448 accidents reported in U.S. general and civil aviation, 655 have been fatal with a total of 1150 on-board fatalities. Head Injury being the most important component contributing to these statistics. One of the main obstructions which causes head impacts are the bulkheads dividing the cabin interiors. Bulkheads in an aircraft or a ship are usually the partitions mounted using the seat tracks and upper mountings that divide different classes or sections of an aircraft. But the actual function of the Bulkhead is to provide structural stability to the aircraft or the ship. When installed by the aircraft door, it protects passengers against the cold winds blowing from the airfield. The passengers sitting on the first row behind the bulkhead in the aircraft are less than three feet away from the bulkhead. Hence in the event of an air crash or an emergency landing the front row passengers seated directly behind bulkheads or cabin class dividers have the tendency to have a head and upper torso impact with the bulkhead making it important to study this criteria in order to reduce the HIC value or the Head Injury Criteria. There are other obstructions in the head paths during a crash inside the cabin interiors of an aircraft. These may cause severe head injuries and in many cases can even cause fatalities. A comprehensive study of the head path can prevent these injuries. This thesis presents a parametric study conducted on the head paths and head trajectories during a crash using Federal Aviation Regulations Part 25 and Part 23. This thesis also presents a parametric study of the properties of the bulkhead, the seat belt, the friction and the seat pitch, and how its variation affects the HIC (Head Injury Criteria) value and the trajectory of the head paths. The attempt is to find the ideal set of properties so as to minimize the HIC value. For example the stiffness of the bulkhead directly affects the structural stability of the aircraft. The more stiff the bulkhead the more strength it imparts to the fuselage and vice versa. But as the bulkhead used gets more stiff the higher is the corresponding value of HIC. The attempt of this experiment is to arrive at the best possible stiffness so as to avoid human fatalities at the same time impart the highest structural stability to the aircraft fuselage. For this purpose, front facing impact tests are simulated using S2 50th percentile Hybrid II human dummy model with a regular two point restraint system as is common in aircraft seating systems. Tests are conducted for a single seated occupant. Sets of parametric studies are conducted by varying the stiffness of the bulkhead, the coefficient of friction between the human dummy and the seat pan & backrest, the seat belt elongation properties and the seat pitch, so as to find the best, most safe combination of material properties for the an allowable HIC value and maximum structural stability. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "December 2006."

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