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Avian flight cannot fail to impress; from the huge migratory distances covered by albatrosses to the dexterity shown by a feeding hummingbird, the performance of birds in flight is remarkable. Until now research into free flight (i.e. not in a wind tunnel or other artificial environment) has been limited to observations from the ground. Here I use a collection of novel techniques, based on the use of onboard instrumentation carried by the bird, to explore if and how this performance might be underpinned by their flexible flight configuration. In the Introduction (chapter 1) to the thesis I investigate previous work into the stability and control of birds in flight. In chapter 2 I investigate a selection of manoeuvres seen commonly in flight, and describe the ways in which they exploit the flexible configuration of the eagle. Then (chapter 3), using an Inertial Measurement Unit (IMU) containing an integrated camera and Pilot-tube I measure the forces acting on the body of the bird in flight, the airspeed of the bird, and using custom-written software, I extract the configuration of the tail from the video. Using the measured configuration of the tail I estimate the lift generated by the tail according to a series of simple aerodynamic models. These are good predictors of the variation in the normal load factor acting on the bird. This suggests that the tail of the eagle is used primarily in soaring flight to balance the bird along the pitch axis. In chapter 4 I further investigate the configuration of the tail, I find that the spread and angle of attack of the tail covary, but that the twist of the tail is adjusted independently. In chapter 5 I explore one manoeuvre, the wing tuck, in more detail. With reference to a 'mean wing tuck' of the key variables I suggest that it is a response to a drop in wing loading, which suggests that it may be a response to atmospheric turbulence. I then investigate the frequency of wing tucking and our principal finding is that it is increased on days when the wind speed is greater, further suggesting that it is a response to atmospheric turbulence. Finally in the Discussion (chapter 6) I summarise the thesis. I also consider future avenues for research into the control and stability of avian flight and discuss some of the limitations of the methods used in this thesis.

Rate of oxygen consumption was used as a method of measuring the metabolic rate of flying locusts. The animals flew into an airstream from a wind tunnel while tethered to a balance so that lift could be determined. Wingbeat frequency was also recorded. The rate of oxygen consumption during flight was found to be determined principally by wingbeat frequency, but using mean values for steady flight good straight line correlations were also found between rate of oxygen consumption and lift, and wingbeat frequency and lift. However, the relationships between these three variables were seen to change during the early part of flight, when lift could be maintained while, in general, wingbeat frequency and rate of oxygen consumption declined. As wingbeat frequency decreased the amount of oxygen used with each wingbeat was found to remain fairly constant, but the amount of lift generated by each wingstroke increased. Therefore the proportion of the locust's total power output which was used to perform aerodynamic work was greater at the lower wingbeat frequency. It was considered that the action of adipokinetic hormone and the change from predominantly carbohydrate to lipid metabolism might be involved in the onset of the period of more economical, steady flight. However, no firm evidence of this was obtained from the experiments which were carried out. When locusts were injected with corpus cardiacum extract 1h before flight, their wingbeat frequency dropped more rapidly than that of saline injected animals. Injection of adipokinetic hormone immediately before flight had a detrimental effect on the locusts' flight performance.

基質輔助鐳射解吸電離飛行時間質譜儀是一種重要的儀器被用來對生物樣品做結構分析，通過諸如源後裂解和碰撞誘導裂解兩種方式實現。然而同碰撞誘導裂解比較，源後裂解具有較低的裂解效率。 / 本課題的目的就是提升我們原有的基質輔助鐳射解吸電離飛行時間質譜儀在結構分析方面的能力。對儀器的改造包括(a)將原有的兩級反射器替換為曲線場反射器(b)安裝一個高壓浮地的碰撞室(c)安裝一個同軸的粒子探測器。曲線場反射器和同軸粒子探測器可以實現母離子跟碎片離子的同時監測，碰撞室可以實現母離子的碰撞裂解。在儀器的性能評估實驗中，母離子和所有的源後裂解的碎片離子同時被探測器記錄。在碰撞誘導裂解實驗中，母離子與碰撞氣體分子發生高能碰撞後大多生成了小質量數的碎片離子，實驗中還發現將碰撞室浮地後，碎片離子的質量解析度和信號強度都有了顯著改進。 / 通過比較曲線場反射器和兩級反射器的性能，我們提出了一種雜化反射器設計，這種反射器在第二片和最後一片電極片上都有可調電壓。第二片和最後一片電極片之間的電場遵循曲線場分佈。這種反射器有兩種操作模式：MS 和MS/MS 模式。類比實驗和分析計算的結果顯示在MS 模式裡，通過調整兩個可調電壓u1 和u2，不同質量離子在反射器裡的反轉點可以被設置在一個最優的位置從而得到最優的質量解析度。在MS/MS 模式裡，一個全質量範圍的譜圖和若干個較窄質量範圍的譜圖可以通過改變兩個可調電壓獲得，其中較窄質量範圍的譜圖具有更高的質量解析度用來分析某個質量範圍內的碎片離子的細節資訊。這些結果表明這種雜化反射器兼具曲線場反射器和兩級反射器的優點。 / Matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOFMS) is an important instrument for structural analysis of biological samples through such as post-source-decay (PSD) or collision-induced dissociation (CID) analysis. However, PSD analysis is a relatively low-efficiency method compared with CID analysis. / This project aims to upgrade the TOF instrument to a high performance TOF/TOF instrument. The modification involves (a) the replacement of the two-stage reflectron with a home-built curved-field reflectron (CFR); (b) the fabrication of a high voltage floated collision cell; and (c) the installation of a coaxial microchannel plate (MCP) detector. The CFR and coaxial detector allow simultaneous reflection of precursor ions and all fragment ions. The collision cell provides an effective means of ion activation (CID). In the performance test, precursor ions with almost all the fragment ions were recorded simultaneously in PSD analysis. In CID experiments, the precursor ions were found to undergo fragmentation due to high energy collision with the target gas and by floating the collision cell to high potential (several kV), the mass resolution and signal intensities of low mass fragment ions were improved substantially. / By comparing the performance of curved-field and two-stage reflectron, a hybrid reflectron was proposed, which has adjustable high voltages U1 and U2 on the second and last electrode element, respectively. The electrostatic potential between the second and last electrode element follows curved-field distribution. There are two operation modes for this reflectron: MS and MS/MS mode. Results from theoretical investigation and experiments showed that in MS mode, optimal energy compensation could be achieved through tuning the values of U1 and U2; in MS/MS mode, a full mass scale spectrum as well as spectra segments with high mass resolution within a narrower mass range could be obtained by setting U1 and U2 with appropriate values. These results indicated that the hybrid reflectron had the advantages both of curved-field reflectron and two-stage reflectron. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Gang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 131-137). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / TABLE OF CONTENTS / LIST OF FIGURES / LIST OF TABLES / ABBREVIATIONS / Chapter Chapter One --- Background Introduction / Chapter 1.1 --- Matrix-assisted laser desorption/ionization (MALDI) --- p.2 / Chapter 1.1.1 --- Laser desorption --- p.2 / Chapter 1.1.2 --- Matrix-assisted laser desorption/Ionization --- p.3 / Chapter 1.2 --- Time-of-flight mass spectrometry --- p.8 / Chapter 1.2.1 --- Linear time-of-flight mass spectrometer --- p.8 / Chapter 1.2.2 --- Reflectron time-of-flight mass spectrometer --- p.9 / Chapter 1.2.2.1 --- Linear-field reflectron --- p.11 / Chapter 1.2.2.2 --- Nonlinear-field reflectron --- p.14 / Chapter 1.3 --- Structural analysis using time-of-flight mass spectrometer --- p.17 / Chapter 1.3.1 --- Post-source decay (PSD) analysis --- p.17 / Chapter 1.3.2 --- Collision-induced dissociation (CID) analysis --- p.20 / Chapter 1.4 --- Project introduction --- p.26 / Chapter Chapter Two --- Instrumentation / Chapter 2.1 --- Instrumentation --- p.28 / Chapter 2.1.1 --- Laser system --- p.28 / Chapter 2.1.2 --- Flight tube and vacuum system --- p.28 / Chapter 2.1.3 --- Ion source --- p.32 / Chapter 2.1.4 --- Deflector and time ion selector --- p.36 / Chapter 2.1.5 --- Two-stage gridless reflectron --- p.39 / Chapter 2.1.6 --- Detectors, digitizer and computer system --- p.42 / Chapter Chapter Three --- Fabrication of the Modified Tandem Time-of-flight Mass Spectrometer / Chapter 3.1 --- Introduction --- p.48 / Chapter 3.2 --- Implementation of a coaxial MCP detector --- p.51 / Chapter 3.3 --- Design, fabrication and implementation of a curved-field reflectron --- p.57 / Chapter 3.4 --- Design, fabrication and implementation of a floated collision cell --- p.61 / Chapter 3.5 --- Summary --- p.66 / Chapter Chapter Four --- Performance Evaluation of the Modified Instrument / Chapter 4.1 --- MS analysis by using the modified instrument --- p.68 / Chapter 4.2 --- MS/MS analysis by using the modified instrument --- p.73 / Chapter 4.2.1 --- Post-source-decay (PSD) analysis --- p.73 / Chapter 4.2.2 --- Collision-induced-dissociation analysis --- p.75 / Chapter 4.3 --- Mass calibration for the modified instrument --- p.84 / Chapter Chapter Five --- A Design of Hybrid Reflectron / Chapter 5.1 --- Introduction of the hybrid reflectron --- p.90 / Chapter 5.2 --- Characterization of the hybrid reflectron --- p.93 / Chapter 5.2.1 --- Calculations using analytical equations --- p.93 / Chapter 5.2.1.1 --- Analytical calculations for MS operation mode --- p.93 / Chapter 5.2.1.2 --- Analytical calculations for MS/MS operation mode --- p.99 / Chapter 5.2.2 --- Simulation experiments by SIMION --- p.106 / Chapter 5.3 --- Calibration of the instrument using the hybrid reflectron --- p.112 / Chapter 5.4 --- Summary --- p.115 / Chapter Chapter Six --- Fabrication and Performance Evaluation of the Hybrid Reflectron / Chapter 6.1 --- Hardware fabrication of the hybrid reflectron --- p.117 / Chapter 6.2 --- Performance evaluation of the hybrid reflectron --- p.121 / Chapter Chapter Seven --- Concluding Remarks --- p.128 / References --- p.131 / Appendix --- p.138 / Chapter Appendix 1 --- Mathematica program for analytical calculations / Chapter Appendix 2 --- Geometry file used in SIMION simulation experiment / Chapter Appendix 3 --- User program for controlling reflectron high voltage

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Impact point dispersion of a direct fire rocket can be drastically reduced with a ring of appropriately sized lateral pulse jets coupled to a trajectory tracking flight control system. The system is shown to work well against uncertainty in the form of initial off-axis angular velocity perturbations as well as atmospheric winds. For an example case examined, dispersion was reduced by a factor of one hundred. Dispersion reduction and mean miss distance are strong functions of the number of individual pulse jets, the pulse jet impulse, and the trajectory tracking window size. Proper selection of these parameters for a particular rocket and launcher combination is required to achieve optimum dispersion reduction to the pulse jet control mechanism. For the lateral pulse jet control mechanism that falls into the category of an impulse control mechanism, the trajectory tracking flight control law provides better reduction in dispersion and mean miss distance than the proportional navigation guidance law especially when small number of individual pulse jets is used. Estimation of body frame components of angular velocity and angular acceleration of a rigid body projectile undergoing general three-dimensional motion using linear acceleration measurements is considered. The results are comparable to those obtained from a conventional Inertial Measurement Unit (IMU) that composes of accelerometers and gyroscopes. From the study of the effect of sensor errors to the measurement and the control performance, the sensitivity of the angular rate estimation to the sensor noise is a strong function of the constellation of these three accelerometers. When more than three point measurements are used, the most effective method to fuse data is with one cluster that contains all sensors. In the conventional IMU, the dispersion and miss distance are less sensitive to the errors from accelerometers than to the gyroscopes. The estimation of angular rates plays essential roles in the performance of the control system in the reduction of dispersion and miss distance. The use of many accelerometers does not guarantee to reduce the sensitivity to errors. The selection of constellation among accelerometers in the data fusion process must be carefully taken into account. / Graduation date: 2002

Many failures of interpersonal communication and coordination in the aircraft cockpit have been found to occur as a result of poor management of flightdeck 'resources'. Crew Resource Management (CRM) is a concept that has evolved within the aviation community to specifically address this issue of resource management. The concept of CRM has necessitated a paradigm shift from individual pilot issues to crew behavior or group-level issues. Despite a decade of research, CRM remains a poorly defined concept. Ongoing research in the field of CRM has led to the development of a few models of CRM and group performance, but although these models provide valuable insight into the issues involved, they fail to present a much needed, coherent theory of crew performance. I believe that the application of the principles of systems engineering can lead to a better definition of the terms and concepts involved in CRM, thereby leading to its better understanding. Using the principles of Structured Analysis and Design Technique (SADT) and IDEF0, I developed a model of crew performance. By treating the crew as a system, performance was analyzed from a CRM perspective, resulting in a functional model of crew performance which acts as a framework for understanding and integrating the various terms and concepts involved in CRM, such as mental models and situation awareness. The model was then applied towards analyzing two aircraft accidents representative of "good" and "bad" CRM. The model is potentially useful in developing objective measures of crew performance so as to enable the establishment of CRM standards for evaluation. A comprehensive representation of crew performance, it can be applied to analyzing aircraft accidents and incidents. It is also potentially useful as an instructional aid in the development of training programs for CRM instructors and check airmen, and in the design of flightdecks. / Graduation date: 1995

A design approach for an aircraft takeoff performance monitoring system (TOPMS) is described. In this approach, it is proposed that the Global Positioning System (GPS) in conjunction with a discrete Kalman Filter be used to determine aircraft acceleration, ground speed, and position relative to the end of the runway. A practical evaluation of the feasibility of this proposal showed clear superiority of a GPS-derived acceleration over a more traditional method employing accelerometers. This study found that, when compared to observations from carefully mounted accelerometers, the GPS-derived observation agreed to within 0.10 metres per second squared ninety percent of the time. Advantages of the GPS-derived observation included a modest noise level, insusceptibility to gravity and temperature-influenced variations, and far simplified mounting criteria. A theoretical dynamic model of an aircraft in contact with the ground was developed in consideration of factors pertaining to runways at far-northern Canadian airports. In the model, factors such as runway slope, wind velocity, wheel friction coefficient, and aircraft control settings were considered constant. While variability in any parameter considered constant by the model could influence the performance of a TOPMS, such variability was deemed beyond the scope of this preliminary investigation of a TOPMS designed specifically for the far-northern environment. A device containing a GPS receiver and data acquisition system was designed and certified, then installed in an aircraft operated by an airline servicing far-northern Canadian airports. The data collected in this manner were used to validate the theoretical model. It was concluded that a projection of displacement can be determined to within an uncertainty of fifteen metres in sufficient time to alert the pilot of an unsafe situation.

A design approach for an aircraft takeoff performance monitoring system (TOPMS) is described. In this approach, it is proposed that the Global Positioning System (GPS) in conjunction with a discrete Kalman Filter be used to determine aircraft acceleration, ground speed, and position relative to the end of the runway. A practical evaluation of the feasibility of this proposal showed clear superiority of a GPS-derived acceleration over a more traditional method employing accelerometers. This study found that, when compared to observations from carefully mounted accelerometers, the GPS-derived observation agreed to within 0.10 metres per second squared ninety percent of the time. Advantages of the GPS-derived observation included a modest noise level, insusceptibility to gravity and temperature-influenced variations, and far simplified mounting criteria. A theoretical dynamic model of an aircraft in contact with the ground was developed in consideration of factors pertaining to runways at far-northern Canadian airports. In the model, factors such as runway slope, wind velocity, wheel friction coefficient, and aircraft control settings were considered constant. While variability in any parameter considered constant by the model could influence the performance of a TOPMS, such variability was deemed beyond the scope of this preliminary investigation of a TOPMS designed specifically for the far-northern environment. A device containing a GPS receiver and data acquisition system was designed and certified, then installed in an aircraft operated by an airline servicing far-northern Canadian airports. The data collected in this manner were used to validate the theoretical model. It was concluded that a projection of displacement can be determined to within an uncertainty of fifteen metres in sufficient time to alert the pilot of an unsafe situation.

Abstract Thanks to the superior material, the volume and sweet spot of a golf club have been bigger and bigger. If the impact surface of a golf club has also been taken care well, the driving effects of a club, it may benefit golf player¡¦s performance in a golf court. By means of a LS-DYNA solver, the researcher analyzed the impact problem of a golf club head. He also calculated velocity¡Bangular velocity and trajectory of golf ball in impact analysis with the C++ program. In this thesis, the researcher analyzed different offcenter impact of a golf club head with various horizontal¡Bvertical curvature. Then he discussed the influence of velocity¡Bangular velocity and trajectory on a golf ball. After that, he generalized the best curvature of club head and discussed (a) the relationship between the best curvature and the club head speed, (b) that between horizontal entering angle¡Bsloping angle and trajectory, and (c) that between vertical entering angle and launching distance.