A real-time digital program for estimating aircraft stability and control parameters from flight test data by using the maximum likelihood method

A computer program (Langley program C1123) has been developed for estimating aircraft stability and control parameters from flight test data. These parameters are estimated by the maximum likelihood estimation procedure implemented on a real-time digital simulation system, which uses the Control Data 6600 computer. This system allows the investigator to interact with the program in order to obtain satisfactory results. Part of this system, the control and display capabilities, is described for this program. This report also describes the computer program by presenting the program variables, subroutines, flow charts, listings, and operational features. Program usage is demonstrated with a test case using pseudo or simulated flight data

Designing a new joint for the iXa walker

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 18).In the fall of 2009, the Purple team developed a walker which allows users to rise from a seated position by folding down to provide a set of handles which the user can push off of to aid in the standing process. The walker relies on a unique geometry and a joint that allows the walker to transition between the standing and kneeling positions. Several members of the team decided to continue the project in attempts to create a beta prototype that improved upon the flaws of the old design in attempts to create a patentable product. My area of focus in the redesign was creating the exterior of the joint including the locking pin interface, the alignment of the legs in relation to the joint, and the integration of the joint into the frame. After deliberating the costs and benefits of each feature, it was decided that the joint would have and axial pin, inline legs, and would be welded to the legs of the walker. These features were then used to create a new joint design. The design process was completed by analyzing the new joint for deflection, optimizing it for weight limitations and material costs, and looking at for design for manufacturing and assembly considerations. Overall, the goal of creating a new joint that could be implemented into a future iteration of the walker was achieved.by Garth S. Grove.S.B

Satellite Power System (SPS) international agreements

The problems in obtaining international agreements on geostationary orbit availability, microwave frequency allocations and microwave frequency standards for satellites transmitting solar power are considered. The various U.S. policy options, strategies and time frames with respect to key issues are analyzed

Opposing shear senses in a subdetachment mylonite zone: Implications for core complex mechanics

[1] Global studies of metamorphic core complexes and low‐angle detachment faults have highlighted a fundamental problem: Since detachments excise crustal section, the relationship between the mylonitic rocks in their footwalls and the brittle deformation in their hanging walls is commonly unclear. Mylonites could either reflect ductile deformation related to exhumation along the detachment fault, or they could be a more general feature of the extending middle crust that has been “captured ” by the detachment. In the first case we would expect the kinematics of the mylonite zone to mirror the sense of movement on the detachment; in the second case both the direction and sense of shear in the mylonites could be different. The northern Snake Range décollement (NSRD) is a classic Basin and Range detachment fault with a well‐documented top‐east of displacement. We present structural, paleo-magnetic, geochronological, and geothermometric evidence to suggest that the mylonite zone below the NSRD locally experienced phases of both east ‐ and west‐directed shear, inconsistent with movement along a single detachment fault. We therefore propose that the footwall mylonites represent a predetachment dis-continuity in the middle crust that separated localized deformation above from distributed crustal flow below (localized‐distributed transition (LDT)). The mylonites were subsequently captured by a moderately dipping brittle detachment that soled down to the middle crust and exhumed them around a rolling hinge into a subhorizontal orientation at the surface, produc-ing the present‐day NSRD. In this interpretation the brittle hanging wall represents a series of rotated upper crustal normal faults, whereas the mylonitic footwall represents one or more exhumed middl

Examining the Relationship Between Throwing Injuries Sustained in Adolescent Baseball Players and Use of an Injury Prevention Smartphone Application Throw Like a Pro

Objective: To describe the use rate of the injury prevention smartphone app “Throw Like a Pro” (TLP), and determine the relationship between use of the app and throwing injuries in adolescent baseball players. Design and Setting: The smartphone application TLP was distributed to adolescent baseball players. Instruction was given on correct use of the application. Stretches, exercises, and application features were demonstrated to subjects. Data on use and injuries was compiled through self-reported surveys. Subjects: A convenience sample of adolescent baseball players (n=20) aged 13-18 from the Babe Ruth Little League organization in Missoula, Montana were selected. Measurements: A modified Kerlan-Jobe Orthopedic Clinic demographic questionnaire was collected on participants including age, current/previous history of shoulder or elbow injury, and years of playing experience. Self-reported surveys collected data pertaining to use of the smartphone application TLP and throwing injuries sustained during the baseball season. Results: Thirty-nine separate time point responses were obtained from participants. Forty-one percent of total responses (n=16/39) revealed shoulder or elbow pain during the season. This is representative of national averages for adolescent baseball players. Athletes who stretched 3-4 times per week experienced less pain than athletes who did not. Pitchers who followed recommended rest periods saw a decreased likelihood of shoulder or elbow pain when compared to pitchers who did not follow recommended rest periods. Conclusions: The incidence rate of overuse injuries in adolescent baseball players is rising. Many rehabilitative exercises post-injury exist, however preventative approaches are lacking. This research reveals the importance of both using pitch count to decrease likelihood of shoulder or elbow pain, as well as the need for ways to increase compliance among athletes. Further research is needed on the use of smartphone applications as a viable source of treatment protocol and injury prevention

Coupling of shells in a carbon nanotube quantum dot

We systematically study the coupling of longitudinal modes (shells) in a carbon nanotube quantum dot. Inelastic cotunneling spectroscopy is used to probe the excitation spectrum in parallel, perpendicular and rotating magnetic fields. The data is compared to a theoretical model including coupling between shells, induced by atomically sharp disorder in the nanotube. The calculated excitation spectra show good correspondence with experimental data.Comment: 8 pages, 4 figure

Leishmaniasis in South West Africa: preliminary notes on host reservoir and vector studies

Studies were undertaken to determine the sandfly fauna of South West Africa with the view to finding possible vectors of leishmaniasis, and to locate a host reservoir. A possible vector species belonging to the Synphlebotomus group of sandflies, which have been incriminated as leishmania vectors in Kenya, has been found in South West Africa. All host reservoir studies have proved negative. Both of these aspects will be the subject for further investigations in the territory

The asymmetrical anthropocene: resilience and the limits of posthumanism

In this article we critique resilience’s oft-celebrated overcoming of modern liberal frameworks. We bring work on resilience in geography and cognate fields into conversation with explorations of the ‘asymmetrical Anthropocene’, an emerging body of thought which emphasizes human-nonhuman relational asymmetry. Despite their resonances, there has been little engagement between these two responses to the human/world binary. This is important for changing the terms of the policy debate: engaging resilience through the asymmetrical Anthropocene framing shines a different light upon policy discourses of adaptative management, locating resilience as a continuation of modernity’s anthropocentric will-to-govern. From this vantage point, resilience is problematic, neglecting the powers of nonhuman worlds that are not accessible or appropriable for governmental use. However, this is not necessarily grounds for pessimism. To conclude, we argue that human political agency is even more vital in an indeterminate world

Magnetic-Field Dependence of Tunnel Couplings in Carbon Nanotube Quantum Dots

By means of sequential and cotunneling spectroscopy, we study the tunnel couplings between metallic leads and individual levels in a carbon nanotube quantum dot. The levels are ordered in shells consisting of two doublets with strong- and weak-tunnel couplings, leading to gate-dependent level renormalization. By comparison to a one- and two-shell model, this is shown to be a consequence of disorder-induced valley mixing in the nanotube. Moreover, a parallel magnetic field is shown to reduce this mixing and thus suppress the effects of tunnel renormalization.Comment: 5 pages, 3 figures; revised version as publishe