The Nyquist approach to stability is used in a form suitable for representation on a chart having conventional Smith chart scales. It is shown how the gain and stability of negative conductance reflection amplifiers of the tunnel-diode type can be simultaneously predicted on this chart. The technique described is particularly useful in the practical design of these amplifiers embedded in networ...

Tunnel monitoring is an important task in civil engineering that aims at determining the stability and safety of a structure by using information about its deformations. In this paper we present the development and the results of a fast method for displacement measurement based on digital images, which allows a deformation analysis along the cross-sections of a tunnel. This technique was create...

The tension in an anterior cruciate ligament graft may not be normal when the femoral tunnel is placed using the single-incision arthroscopic technique because the femoral tunnel is drilled through the tibial tunnel. We hypothesized that the in vivo tensile behavior of the double-looped semitendinosus and gracilis tendon graft can be normal or abnormal compared with the native anterior cruciate...

nowadays deep excavations are needed for construction of foundation of high rise buildings, providing space for parking and etc. in some cases deep excavations may be constructed in the vicinity of the subway tunnels and causes unpredicted extra displacements and internal forces in tunnel lining of tunnels which were not designed for them and consequently affect serviceability of tunnel. theref...

objective: yield components and genetic contribution have the most important in final yield and breeding programs of crop plants. for this purpose, 20 varieties of grapevines with russia origin were evaluated in urmia and takestan research station (under full irrigation and drought stress). methods: twenty grapevine genotypes were evaluated in urmia and takestan research station (under full irr...

The paper presents the parallel implementation of a multibody formulation for the analysis of the dynamic stability of a soft-in-plane tiltrotor configuration, with regard to the groundand airresonance phenomena. A multibody model of a tiltrotor semispan wind tunnel model has been used to investigate the phenomenon. An original multibody, multidisciplinary formulation has been used; its impleme...

Dimensionless coefficient () in convergence confinement method shows the relaxation of stress in the wall of the tunnel at different excavation movements. This factor is considered a constant number in previous studies and tunnel geometric characteristics (such as depth, cross-section shape, radius, soil material, etc.) are not included in its determination; however, ignoring these effects can...

The research group of Professor Hideo Ohno of the Center for Spintronics Integrated Systems, the Research Institute of Electrical Communication, and the WPI Advanced Institute for Materials Research, together with ULVAC, successfully fabricated magnetic tunnel junctions with a diameter reduced to 11 nm. They demonstrated that high thermal stability and low power consumption can be simultaneousl...

This work describes the design and construction of a fully adaptive aircraft configuration used as an experimental testbed for aerodynamic modeling and flight control. The adaptive model is designed to achieve large scale shape changes in order to investigate morphing for multi-mission UAVs. There are five independent planform changes along with independent twist control for each wing. Wind tun...