This paper analyzes the impact on mobile telephony diffusion patterns of the two predominant payment regimes, calling party pays (CPP) and receiving party pays (RPP), for mobile termination services. By applying instrumental variable techniques to panel data we account for a possible interdependency of penetration rates and regulatory interventions. For this purpose we use data on political and...

It is important for search and pay-per-click engines to penetration test their click fraud detection systems, in order to find potential vulnerabilities and correct them before fraudsters can exploit them. In this paper, we describe: (1) some goals and desirable qualities of a click fraud penetration testing system, based on our experience, and (2) our experiences with the challenges of buildin...

Soil stiffness constants govern the soil sinkage and the pressure-sinkage behaviour of the soil under load. To determine soil stiffness constants in Upadhyaya model under field conditions, a field reflecting general character of an agricultural soil was selected and multiplate penetration tests were conducted. The soil stiffness constants in Upadhyaya model were determined from five sets of soi...

The paper begins with a review of screw algebra including dual numbers, unit line vectors, dual vectors, screws, line coordinates, and screw coordinates and summarizes the essential rules of operation for screw algebra. A significant advantage of the algebra is that geometric, kinematic, and dynamic equations of a rigid body can be expressed in a concise and compact form. Several physical quant...

STUDY DESIGN Retrospective evaluation of complications in 180 consecutive patients with cervical disorders who had been treated by using pedicle screw fixation systems. OBJECTIVES To determine the risks associated with pedicle screw fixation in the cervical spine and to emphasize the importance of preoperative planning and surgical techniques in reducing the risks of this procedure. SUMMARY...

BACKGROUND Screw perforation and varus collapse are common complications of treatment with a PHILOS (proximal humerus internal locking system) plate for proximal humerus fractures, which are associated with improper screw length selection and lack of medial column support. The purposes of this study were: (1) to measure the proper length of periarticular screws of the PHILOS plate in the humera...

OBJECTIVE To investigate risk factors for S1 screw loosening after lumbosacral fusion, including spinopelvic parameters and paraspinal muscles. METHODS We studied with 156 patients with degenerative lumbar disease who underwent lumbosacral interbody fusion and pedicle screw fixation including the level of L5-S1 between 2005 and 2012. The patients were divided into loosening and non-loosening ...

Recently it has been shown that anatomic tibial graft fixation in anterior cruciate ligament (ACL) reconstruction is preferable in order to increase isometry and knee stability. To facilitate anatomic patellar tendon graft fixation, customized graft length shortening is necessary. The purpose of this study was to compare the initial fixation strength of four different shortened patellar tendon ...

In this paper, the design and simulation of a symmetrical waveguide filter are presented based on insertion loss method. The designed WR-34 is operating at 28 GHz, where its dimensions a=4.32mm b=8.64mm, fractional bandwidth 2.15% return level better than 16 dB, frequency range from 22Ghz to 33 GHz. structure 5 th -order bandpass with five resonators six circular inductive irises. order optimiz...

Orthopedic screw removal has proven itself to be a challenge. Access to a Screw Removal Set (TM Synthes) is essential. But what options are available when it cannot remove a broken screw in a lesser toe on a background of osteomyelitis of a lesser toe? A young healthy patient had undergone a 2nd and 3rd toe proximal interphalangeal joint (PIPJ) and distal interphalangeal joint (DIPJ) fusion usi...