a parametrik investigation was conducted to study the non-linear behavior of precast and cast-in-place reinforced concrete beam-column connections subjected to tabas seismic forces (1979). the behavior of these types of connections in a four stories structure with respect to strength, ductility , stiffness, and bond deterioration at the joint core are presented and discussed. calculation result...

This paper features the proposed modeling and design of a Robust Decentralized Periodic Output Feedback (RDPOF) control technique for the active vibration control of smart flexible multimodel Euler-Bernoulli cantilever beams for a multivariable (MIMO) case by retaining the first 6 vibratory modes. The beam structure is modeled in state space form using the concept of piezoelectric theory, the E...

Analytic calculation and numerical simulations reveal a multiline structure in the spectrum of coherent dipole oscillations in the colliding beam system due to coupled synchrobetatron beam-beam modes. The model employed in the analysis involves linearization of the beam-beam kick and takes into account the fact that the length of the colliding bunches is finite. In the present paper, we discuss...

As is known, a totally reflected beam experiences a lateral displacement from its position predicted by the geometric optics because each of its plane-wave components undergoes a different phase change [1]. For the beam reflected from an interface, the lateral beam shift (the so-called Goos-Hänchen effect) is usually much less than the beam width. However, larger beam shifts may occur in the la...

Interaction between the bunches in the NLC main linac via long range wakefields can cause a beam breakup instability. Although the magnitude of the long range wakefields for an ideal NLC structure is below the instability threshold, the wake increases when structure manufacturing errors are taken into account. In case of large errors, the developing instability can result in the projected emitt...

We analyze transmission of a layered photonic structure ~a one-dimensional photonic crystal! consisting of alternating slabs of two materials with positive and negative refractive index. For the periodic structure with zero averaged refractive index, we demonstrate a number of unique properties of the beam transmission observed in strong beam modification and reshaping. © 2003 American Institut...

Beam emittance dilution caused by wakefield effects is one of the important issues in the SLC linac. The detection of beam induced dipole mode signals in the C.. band range could provide a direct measure of the strength of transverse wakefield kicks the beam experiences in the accelerating structures. We investigate the applicability of these microwave signals for beam steering purposes. The RF...

Complex amplitude and polarization distribution of an optical beam plays a dominant role in shaping the focused structure of the beam. It is therefore possible to engineer the focal spot using the pupil function manipulation. Helical phase structure arising due to phase singularity in the wave front plays an important role in shaping the focal spot. Tight focusing of an optical beam produces in...

Ion beam irradiation-induced nanoporous structure formation was investigated on GaSb, InSb, and Ge surfaces via controlled point defect creation using a focused ion beam (FIB). ‎This paper compares the nanoporous structure formation under the same extent of point defect creation while changing the accelerating voltage and ion dose. Although the same number of point defects were created in each ...