6,153 research outputs found

    Thin film strain transducer

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    A strain transducer system and process for making the same is disclosed. A beryllium copper ring having four strain gages is electrically connected in Wheatstone bridge fashion to the output instrumentation. Tabs are bonded to a balloon or like surface with strain on the surface causing bending of a ring which provides an electrical signal through the gages proportional to the surface strain. A photographic pattern of a one half ring segment as placed on a sheet of beryllium copper for chem-mill etch formation is illustrated

    Thin film strain transducer

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    Previous attempts to develop an appropriate sensor for measuring the stress or strain of high altitude balloons during flight are reviewed as well as the various conditions that must be met by such a device. The design, development and calibration of a transducer which promises to satisfy the necessary design constraints are described. The thin film strain transducer has a low effective modulus so as not to interfere with the strain that would naturally occur in the balloon. In addition, the transducer has a high sensitivity to longitudinal strain (7.216 mV/V/unit strain) which is constant for all temperature from room temperature to -80 C and all strains from 5 percent compression to 10 percent tensile strain. At the same time, the sensor is relatively insensitive (0.27 percent) to transverse forces. The device has a standard 350 ohm impedance which is compatible with available bridge balance, amplification and telemetry instrumentation now available for balloon flight. Recommendations are included for improved coatings to provide passive thermal control as well as model, tethered and full scale flight testing

    Hypervelocity impact effects Semiannual progress report

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    Effects of target strength on cratering process caused by impact of hypervelocity projectile

    An analytical and experimental study of the behavior of semi-infinite metal targets under hypervelocity impact

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    The material strength and strain rate effects associated with the hypervelocity impact problem were considered. A yield criterion involving the second and third invariants of the stress deviator and a strain rate sensitive constitutive equation were developed. The part of total deformation which represents change in shape is attributable to the stress deviator. Constitutive equation is a means for analytically describing the mechanical response of a continuum under study. The accuracy of the yield criterion was verified utilizing the published two and three dimensional experimental data. The constants associated with the constitutive equation were determined from one dimensional quasistatic and dynamic experiments. Hypervelocity impact experiments were conducted on semi-infinite targets of 1100 aluminum, 6061 aluminum alloy, mild steel, and commercially pure lead using spherically shaped and normally incident pyrex projectiles

    Strain Rate Sensitive Constitutive Equations

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    Stain rate sensitive constitutive equations using yield criterion which incorporates second and third invariants of stress deviato

    Microwave-assisted synthesis of 3-aminobenzo[b]thiophene scaffolds for the preparation of kinase inhibitors

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    Microwave irradiation of 2-halobenzonitriles and methyl thioglycolate in the presence of triethylamine in DMSO at 130 °C provides rapid access to 3-aminobenzo[b]thiophenes in 58–96% yield. This transformation has been applied in the synthesis of the thieno[2,3-b]pyridine core motif of LIMK1 inhibitors, the benzo[4,5]thieno[3,2-e][1,4]diazepin-5(2H)-one scaffold of MK2 inhibitors and a benzo[4,5]thieno[3,2-d]pyrimidin-4-one inhibitor of the PIM kinases

    Understanding Hope: A Review of Measurement and Construct Validity Research

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    Hope has been discussed by philosophers, theologians, educators, and scientists, to name but a few groups of people, over the preceding two millennia. During the last 15 years, C. R. Snyder and his colleagues at the University of Kansas have developed a theory and associated measures of the hope construct that have received extensive, detailed attention both within and outside the field of psychology. In this chapter, we describe Snyder\u27s hope model and some of the research findings that have supported the validity of this construct. Beginning with a conceptual definition of hope, we move to relevant findings about the usefulness of hope in the lives of individuals in various life arenas. We describe measures developed for assessing hope in children and adults, as well as current issues associated with the validity of hope measurement. Finally, we discuss future directions for further investigation of hope

    A common procedure for using the Kinetic Family Drawing (KFD) in educational psychology practice: an exploratory study using the Delphi method

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    While the Kinetic Family Drawing (KFD) is used in educational psychology (EP) practice, the research suggests there is no agreement about the procedure for administering and interpreting the tool. Current literature identifies the KFD may be informed by a range of psychological theories and for differing purposes in both clinical and educational settings. One such approach to its use as a projective assessment through application of psychoanalytic theory to develop hypotheses about unconscious processes that may be influencing a child or young person. However, psychoanalytic techniques appear less popular amongst UK EPs, and some of the challenges include a lack of training in this area and the provision of a best practice framework. In order to investigate further, this study used a multi-staged survey design to gain a consensus opinion amongst EPs. This exploratory piece of research sets out to address the following question: What are the features of an effective use of the kinetic family drawing (KFD) as a projective technique? Three rounds of the survey ran via email using the Delphi approach. Percentage of agreement was used to establish a consensus of opinion amongst eight participants about the key competencies needed for effective administration and interpretation of the KFD. Consensus was reached that 112 competencies of skills, knowledge and process are essential in all situations. Statements which were considered unique to the KFD from those that were general assessment skills were explored and separated and used to develop a KFD best practice framework
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