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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents instrumentation and telemetry system techniques used in free-flight research drop model testing at the NASA Langley Research Center. The free-flight drop model test technique is used to conduct flight dynamics research of high performance aircraft using dynamically scaled models. The free-flight drop model flight testing supplements research using computer analysis and wind tunnel testing. The drop models are scaled to approximately 20% of the size of the actual aircraft. This paper presents an introduction to the Free-Flight Drop Model Program which will be followed by a description of the current instrumentation and telemetry systems used at the NASA Langley Research Center, Plum Tree Test Site. The paper describes three telemetry downlinks used to acquire the data, video, and radar tracking information from the model. Also described are two telemetry uplinks, one used to fly the model employing a ground based flight control computer and a second to activate commands for visual tracking and parachute recovery of the model. The paper concludes with a discussion of free-flight drop model instrumentation and telemetry system development currently in progress for future drop model projects at the NASA Langley Research Center.

by Poon Kai Lok. / Title also in Chinese. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 89-90. / LIST OF TABLES --- p.iv / LIST OF FIGURES --- p.v / ACKNOWLEDGEMENTS --- p.vii / ABSTRACT --- p.viii / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- LASER PULSE INDUCED DEFORMATION OF DROPLET ： PART I / Chapter 2.1 --- Curvature and surface tension on a deformed surface on the droplet --- p.6 / Chapter 2.2 --- Solution of the Navier-Stokes equation in the absence of viscosity --- p.8 / Chapter CHAPTER 3 --- GEOMETRIC OPTICS ： CALCULATION OF INTERNAL INTENSITY / Chapter 3.1 --- Trace of a narrow light beam inside a droplet --- p.14 / Chapter 3.2 --- Intensity within droplet --- p.16 / Chapter 3.3 --- Mean intensity on the surface of a concentric sphere --- p.25 / Chapter 3.4 --- Intensity on the surface of the droplet --- p.28 / Chapter CHAPTER 4 --- PHYSICAL OPTICS ： MIE SCATTERING / Chapter 4.1 --- "Formalism of Mie Scattering (Mie, 1908〕" --- p.35 / Chapter 4.2 --- Expression of Fl and its result --- p.39 / Chapter CHAPTER 5 --- LASER PULSE INDUCED DEFORMATION OF DROPLET ： PART II / Chapter 5.1 --- Including viscosity --- p.50 / Chapter 5.2 --- Droplet deformation --- p.52 / Chapter 5.3 --- Discussion --- p.58 / Chapter CHAPTER 6 --- TWO FLUID PROBLEM / Chapter 6.1 --- Derivation and discussion of the equation of motion --- p.61 / Chapter 6.2 --- Calculated results --- p.65 / Chapter 6.3 --- The incompressibi1ity assumption --- p.73 / Chapter CHAPTER 7 --- CONCLUSION --- p.76 / APPENDIX A --- p.78 / APPENDIX B --- p.80 / APPENDIX C --- p.82 / APPENDIX D --- p.88 / REFERENCES --- p.89

Despite the higher incidence of anterior cruciate ligament injuries in pediatric female populations, limited research has investigated sex-differences in youth biomechanics. Furthermore, research involving jump mechanics typically requires participant to follow a set protocol, such as sticking the landing. To reduce variability and improve reliability, trails where participants fail to meet the required protocol are discarded; however, significant clinical findings may be elucidated from these trials. The purpose of this thesis was to provide a complete biomechanical analysis of unanticipated single-leg drop-jump landings in youth athletes. Thirty-two healthy youth athletes completed unanticipated single-leg drop-jump landings on their dominant limb. Trials where participants shifted foot position or touched the ground with the contralateral leg were categorized as failed. Drop-jump landings were time-normalized using landmarks within the drop-jump task. Statistical parametric mapping (SPM) determined time-varying sex-differences in muscle onset time, co-activation, kinematics and kinetics. Wilcoxon signed-rank tests and paired sample t-tests compared lower-limb kinematics, centre-of-mass excursion and muscle activation amplitudes during the successful and failed landings. A logistic regression model was also fit to predict the likelihood of a successful landing. SPM identified significantly greater trunk flexion angle in males during the deceleration, flight, and landing phase of the drop-jump. Greater quadriceps-gastrocnemius co-activation was identified during the flight phase in female participants and independent sample t-test identified longer muscle onset time in the vastus lateralis of male participants. When comparing failed and successful landings greater hip abduction and less external rotation angles were observed during the successful trials. In addition, greater preparatory muscle activation was observed in the rectus femoris and semitendinosus during the flight phase of the failed landings. A logistic regression model, which included eight kinematic and neuromuscular variables, offered a training classification accuracy of 70% and a leave-one-out cross-validation accuracy of 65%. In conclusion, females land in a more erect posture and may be less effective at dissipating landing forces. In addition, greater co-activation and shorter pre-activations of the lower limb musculature may indicate a less effective muscle activation strategy in females. Furthermore, hip kinematics and the surrounding musculature play an important role in controlling successful and failed unanticipated landings. The variables included in the logistic regression model indicate which key factors are linked to landing a jump successfully. Training modalities aimed at improving landing mechanics should therefore focus on modifying these variables.

by Chan Chiu Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves [68-69]). / by Chan Chiu Wah. / List of Tables --- p.i / List of Figures --- p.ii / Acknowledgments --- p.iv / Abstract --- p.v / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Theory --- p.4 / Chapter 2.1 --- Radiation pressure on a droplet --- p.4 / Chapter 2.2 --- Laser levitation of a droplet --- p.7 / Chapter 2.3 --- Dynamic of a laser levitated spherical droplet --- p.9 / Chapter Chapter 3 --- Experiment --- p.11 / Chapter 3.1 --- Principle and calibration of the position sensor --- p.14 / Chapter 3.2 --- Measurement of the levitated laser beam waist --- p.16 / Chapter Chapter 4 --- Results and discussion --- p.18 / Chapter 4.1 --- Vertical motion due to MDRs --- p.22 / Chapter 4.2 --- Artifacts in the displacement --- p.26 / Chapter 4.3 --- Elastic scattering light intensity --- p.28 / Chapter 4.4 --- Effect of the size of beam waist --- p.31 / Chapter 4.5 --- Small size parameter droplet --- p.33 / Chapter Chapter 5 --- Conclusion and future outlook --- p.35

To design a cyclone abatement system for particulate control, it is necessary to accurately estimate cyclone performance. In this cyclone study, new theoretical methods for computing travel distance, numbers of turns and cyclone pressure drop have been developed. The flow pattern and cyclone dimensions determine the travel distance in a cyclone. The number of turns was calculated based on this travel distance. The new theoretical analysis of cyclone pressure drop was tested against measured data at different inlet velocities and gave excellent agreement. The results show that cyclone pressure drop varies with the inlet velocity, but not with cyclone diameter. Particle motion in the cyclone outer vortex was analyzed to establish a force balance differential equation. Barth??s "static particle" theory, particle (with diameter of d50) collection probability is 50% when the forces acting on it are balanced, combined with the force balance equation was applied in the theoretical analyses for the models of cyclone cut-point and collection probability distribution in the cyclone outer vortex. Cyclone cut-points for different dusts were traced from measured cyclone overall collection efficiencies and the theoretical model for calculating cyclone overall efficiency. The cut-point correction models (K) for 1D3D and 2D2D cyclones were developed through regression fit from traced and theoretical cut-points. The regression results indicate that cut-points are more sensitive to mass median diameter (MMD) than to geometric standard deviation (GSD) of PSD. The theoretical overall efficiency model developed in this research can be used for cyclone total efficiency calculation with the corrected d50 and PSD. 1D3D and 2D2D cyclones were tested at Amarillo, Texas (an altitude of 1128 m / 3700 ft), to evaluate the effect of air density on cyclone performance. Two sets of inlet design velocities determined by the different air densities were used for the tests. Experimental results indicate that optimal cyclone design velocities, which are 16 m/s (3200 ft/min) for 1D3D cyclones and 15 m/s (3000 ft/min) for 2D2D cyclones, should be determined based on standard air density. It is important to consider the air density effect on cyclone performance in the design of cyclone abatement systems.

Experimental and numerical analyses were both adopted in the thesis. First, the BGA with three different solder ball components and pads, were investigated and their strength was affected by drop tests and thermal cycling test. Then the concept of numerical simulation to do the follow-up analysis was adopted. the relationships of stress, strain, and creep strain energy density were found. The lead-free solder ball has better resistance to the drop test with lower silver content; on the contrary, it has better properties due to thermal cycling tests with higher silver content. In the drop test, the failure of solder ball were found obviously in the packages that near four corner of the test board, and concentrated in the diagonal screw holes. The failure of solder ball was distributed over the peripheral of the package in the middle cross section of test board. Comparing the different position of 15 packages due to drop test, the amount of failed solder balls showed that the package positions U3, U8, U13 was obviously fractured, and the situation of fracture was relatively slight in the positions of U1, U5, U6, U7, U9, U10, U11, U15. In the fatigue life prediction of thermal cycling test, the simplified model of package in 45¢X direction was mostly close to the experimental data. After the except ion of the solder ball with failure mode A1, the major failure mode in drop test was mode B3. But the mode C was the majority of thermal cycling test. The structure and intensity of SMD play an important role on above experiments; the better choice of SMD can reduce the rate of failure mode A1, and improve the accuracy of the experiment.

System Andersson AB is a company located in Jönköping that works with developing computer systems for the mechanical engineering industry. As of today, when this report is written, the company is working on the development of a new Manufacturing Planning and Control (MPC) system. This new system aims to create not only a user friendly interface but also a modern, stylish interface. To achieve this, the company has decided to work with a, for them, new application framework; Windows Presentation Foundation (WPF).System Andersson is well known for developing systems for different kinds of touch screens, this project is no exception. For this new user interface the company wishes to implement different types of Drag&Drop functionality. They have not had enough time themselves to study and finish these parts and therefore they have chosen to hand out the task as a thesis project.The first step in the process was to get to know what WPF was and how it works, and especially how it handles Drag&Drop. The goal was to put together some sort of class library and a presentation that together were to give the company a quick guide on how they could implement the functionality into their system.As the framework was new for the company there were also a wish for alternative solutions that demonstrated how the WPF framework could be used to solve the task in as many ways as possible.This report contains a summary of the projects procedure and result. In the report the results are presented and motivated as well as demonstrated in the appendix.