scholarly journals AERODYNAMIC ANALYSIS OF THE CLARK YH AIRFOIL

2021 ◽  
Vol 19 (1) ◽  
pp. 37-46
Author(s):  
Vasile PRISACARIU ◽  

The analysis of the performance of aerodynamic airfoils leads to optimized approaches regarding the pre-design of fixed and rotating lifting surfaces, with implications on the global characteristics and performances of aircraft. The 2D aerodynamics of the airfoils provides indications on the aeromechanical behavior of the selected geometric elements, which may come as constructive solutions depending on the typology of the missions and the initial requirements of the project. The article provides a scrutiny of and certain educational perspectives on the Clark YH profile analysis, using freeware tools (Javafoil, Profiles and XFLR5).

2019 ◽  
Vol 111 ◽  
pp. 100583
Author(s):  
Spencer J. Stebbins ◽  
Eric Loth ◽  
Andy P. Broeren ◽  
Mark Potapczuk

Author(s):  
John W. Coleman

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.


Author(s):  
S.F. Corcoran

Over the past decade secondary ion mass spectrometry (SIMS) has played an increasingly important role in the characterization of electronic materials and devices. The ability of SIMS to provide part per million detection sensitivity for most elements while maintaining excellent depth resolution has made this technique indispensable in the semiconductor industry. Today SIMS is used extensively in the characterization of dopant profiles, thin film analysis, and trace analysis in bulk materials. The SIMS technique also lends itself to 2-D and 3-D imaging via either the use of stigmatic ion optics or small diameter primary beams.By far the most common application of SIMS is the determination of the depth distribution of dopants (B, As, P) intentionally introduced into semiconductor materials via ion implantation or epitaxial growth. Such measurements are critical since the dopant concentration and depth distribution can seriously affect the performance of a semiconductor device. In a typical depth profile analysis, keV ion sputtering is used to remove successive layers the sample.


Crisis ◽  
2020 ◽  
Vol 41 (4) ◽  
pp. 288-295 ◽  
Author(s):  
Nadia Bounoua ◽  
Jasmeet P. Hayes ◽  
Naomi Sadeh

Abstract. Background: Suicide among veterans has increased in recent years, making the identification of those at greatest risk for self-injurious behavior a high research priority. Aims: We investigated whether affective impulsivity and risky behaviors distinguished typologies of self-injurious thoughts and behaviors in a sample of trauma-exposed veterans. Method: A total of 95 trauma-exposed veterans (ages 21–55; 87% men) completed self-report measures of self-injurious thoughts and behaviors, impulsivity, and clinical symptoms. Results: A latent profile analysis produced three classes that differed in suicidal ideation, suicide attempts and nonsuicidal self-injury (NSSI): A low class that reported little to no self-injurious thoughts or behaviors; a self-injurious thoughts (ST) class that endorsed high levels of ideation but no self-harm behaviors; and a self-injurious thoughts and behaviors (STaB) class that reported ideation, suicide attempts and NSSI. Membership in the STaB class was associated with greater affective impulsivity, disinhibition, and distress/arousal than the other two classes. Limitations: Limitations include an overrepresentation of males in our sample, the cross-sectional nature of the data, and reliance on self-report measures. Conclusion: Findings point to affective impulsivity and risky behaviors as important characteristics of veterans who engage in self-injurious behaviors.


Sign in / Sign up

Export Citation Format

Share Document