The Experts below are selected from a list of 10179 Experts worldwide ranked by ideXlab platform

Alexander Laufer - One of the best experts on this subject based on the ideXlab platform.

  • what does the construction Foreman do
    Construction Management and Economics, 1991
    Co-Authors: Igal M Shohet, Alexander Laufer
    Abstract:

    Despite his acknowledged role in the execution of construction projects, the crew Foreman's function has received little attention. The study described here tries to answer three questions: How does the Foreman divide his workday time and on what subjects? With whom does he communicate? Can a correlation be detected between the way he divides his time and the performance of his crew? The research is based on a sample of 24 foremen in the USA and 32 in Israel. The findings throw more light on the perennial discussion to what extent the Foreman is manager or supervisor, and whether one can replace replanning with preplanning.

  • span of control of construction Foreman situational analysis
    Journal of Construction Engineering and Management-asce, 1991
    Co-Authors: Alexander Laufer, Igal M Shohet
    Abstract:

    The function of the crew Foreman has not received the degree of attention in research the crucial role in construction deserves. In this study, we investigate aspects of the Foreman's role that have strong implications on the productivity of the crew. By enquiring into how the Foreman divides workaday time between various functions and activities, how these are affected by the size of the crew, what factors determine the span of control, and what effect the size of the crew has on its performance, the study has come to the conclusion that: (1) The size of the crew and the managerial assistance, if given, affect the mode of daily activities; (2) the size of the crew can vary considerably, depending on circumstances; (3) the size of the crew can affect its performance; and, finally, (4) the size of the crew has to be adapted to prevailing conditions.

Joseph S Alpert - One of the best experts on this subject based on the ideXlab platform.

  • which patent foramen ovales need closure to prevent cryptogenic strokes
    The American Journal of Medicine, 2017
    Co-Authors: James E Dalen, Joseph S Alpert
    Abstract:

    Abstract Patients with cryptogenic strokes are more likely to have a patent foremen ovale than in the general population. It is speculated that these strokes are due to paradoxical embolism, that is, passage of a venous thrombus across the patent foremen ovale to enter the arterial circulation, resulting in an embolic stroke. Venous thromboembolism is rarely present in these cases of cryptogenic stroke. Thousands of patients with cryptogenic strokes have undergone transcatheter closure of their patent foremen ovale via a variety of devices. The first 3 randomized clinical trials comparing patent foremen ovale closure with medical therapy failed to show a significant advantage of patent foremen ovale closure. Three additional trials reported in 2017 had longer years of follow-up and demonstrated an advantage of patent foremen ovale closure versus medical therapy. Analysis of their data indicated that patent foremen ovale closure in patients with an atrial septal aneurysm in addition to a patent foremen ovale had a very significant decrease in cryptogenic strokes ( P P  = .37). Aneurysms of the atrial septum are easily recognized by echocardiography and are present in approximately one-third of patients with patent foremen ovales. These data suggest that closure of patent foremen ovales in patients with an atrial septal aneurysm is indicated. In patients with a patent foremen ovale without an aneurysm of the atrial septum, patent foremen ovale closure is not indicated.

C J J Westermann - One of the best experts on this subject based on the ideXlab platform.

  • patent foramen ovale causing position dependent shunting in a patient when laying down her corset
    European Respiratory Journal, 2001
    Co-Authors: Jan C Grutters, J Ten M Berg, J Van Der Zeijden, W Jaarsma, J M P G Ernst, C J J Westermann
    Abstract:

    A 75-;yr-old female presented with platypnoea and orthodeoxia, shortly after laying down an old and pinching corset. The injection of activated Haemaccel in the right cubital vene during transoesophageal echocardiography, in the upright position, revealed a direct blood flow from the superior caval vein at a patent foremen ovale, consequently opening it and causing a large right-to-left shunt which was calculated at 28.5%. In the supine position there was only a minimal opening of the patent foremen ovale with a calculated right-to-left shunt of 9.5%. The patent foremen ovale was successfully closed percutaneously with a CardioSEALTM.

A M Stewart - One of the best experts on this subject based on the ideXlab platform.

  • interatomic forces phonons the Foreman lomer theorem and the blackman sum rule
    arXiv: Statistical Mechanics, 2011
    Co-Authors: A M Stewart
    Abstract:

    Foreman and Lomer proposed in 1957 a method of estimating the harmonic forces between parallel planes of atoms of primitive cubic crystals by Fourier transforming the squared frequencies of phonons propagating along principal directions. A generalized form of this theorem is derived in this paper and it is shown that it is more appropriate to apply the method to certain combinations of the phonon dispersion relations rather than to individual dispersion relations themselves. Further, it is also shown how the method may be extended to the non-primitive hexagonal close packed and diamond lattices. Explicit, exact and general relations in terms of atomic force constants are found for deviations from the Blackman sum rule which itself is shown to be derived from the generalized Foreman-Lomer theorem.

  • interatomic forces phonons the Foreman lomer theorem and the blackman sum rule
    International Journal of Modern Physics B, 2001
    Co-Authors: A M Stewart
    Abstract:

    Foreman and Lomer proposed in 1957 a method of estimating the harmonic forces between parallel planes of atoms of primitive cubic crystals by Fourier transforming the squared frequencies of phonons propagating along principal directions. A generalized form of this theorem is derived in this paper and it is shown that it is more appropriate to apply the method to certain combinations of the phonon dispersion relations rather than to individual dispersion relations themselves. Further, it is also shown how the method may be extended to the hexagonal close packed and diamond lattices. Explicit, exact and general relations in terms of atomic force constants are found for deviations from the Blackman sum rule which itself is shown to be derived from the generalized Foreman–Lomer theorem.

Itzhak Kronzon - One of the best experts on this subject based on the ideXlab platform.

  • Left Atrial Hypertension as a Result of Occlusion of a Patent Foreman Ovale
    Circulation-cardiovascular Interventions, 2010
    Co-Authors: James Slater, Itzhak Kronzon
    Abstract:

    A 70-year-old woman with a history of hypertension, pulmonary hypertension, and transient ischemic attack was referred for transcatheter closure of a patent foramen ovale (PFO). The patient complained of dyspnea on exertion but showed no other signs of heart failure. A previous transthoracic echocardiogram had documented normal left ventricular size and function, continuous left-to-right shunting across the PFO, right ventricular enlargement, severe pulmonary hypertension, and a Qp:Qs ratio of 1.4:1 calculated by Doppler echocardiography. The patient was brought into the procedure room to undergo catheter-based closure of the PFO. Transesophageal echocardiography was performed throughout the procedure and confirmed the presence of a characteristic PFO with left-to-right shunting across the space between the septum primum and secundum (Figure 1). Figure 1. Color Doppler image of left-to-right shunt across a characteristic PFO, demonstrating flow between the septum primum and secundum. LA indicates left atrium; RA, right atrium. Venous access was obtained through …