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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A study of safety in lift industry /

Leung, Shui-cheung, January 1998 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references.
2

Seismic Performance of Rail-Counterweight System of Elevator in Buildings

Rildova 06 October 2004 (has links)
Elevators serve a critical function in essential facilities such as hospitals and need to remain operational during and after earthquakes. However, they are still known to malfunction during earthquakes even after several design and sensing improvements required by the current code have been incorporated. Most of the damages were experienced or caused by the rail-counterweight system. Being the heaviest component of an elevator, the counterweight induced strong dynamic effects to the guiding system sometimes even collided and damaged the passenger car. A realistic analytical model of rail-counterweight system of an elevator that includes details of the supporting system is developed in this study. The nonlinearities caused by closing of the code specified clearances play an important role in determining the dynamic behavior of the system, and are thus included in this study. Also included are the acceleration inputs from different floor of building and the effect of different location of the counterweight along the guide rail. Parametric study is carried out to investigate the effect of different parameters on the seismic responses of the rail-counterweight system. In order to improve the seismic performance of the rail-counterweight system, several protective schemes are investigated. One simple approach is to increase the damping of the system using additional discrete viscous dampers. However, there is not much space available for installing the devices, and placement parallel to the spring at the roller guide assemblies is not quite effective due to contact between the restraining plate at the roller guide assemblies and the rail that makes the roller guides ineffective. Another method is to convert the top part of the weights into a tuned mass damper. This method can reduce the maximum stress in the rail if designed properly. The effectiveness of the passive tuned mass damper can be improved further by using it in an active mode by installing an actuator between the mass damper and the counterweight frame. The numerical results that confirm the effectiveness of such an active tuned mass damper are presented. As an alternative to the fully active control scheme, a semi-active control scheme using a magnetorheological damper device between the mass damper and the frame is also studied. This control approach is found to be as effective in reducing the seismic response as a fully active scheme. Since this MR damper can be operated using a simple battery, the external power requirements for implementation of this approach are quite minimal. / Ph. D.
3

A search for an index of lift traffic performance

Wareing, Malcolm January 1985 (has links)
No description available.
4

The Adaptation of a Thunder Bay Grain Elevator

Gillies, Richard 22 March 2011 (has links)
This thesis is an exploration of spatial possibilities within a concrete terminal grain elevator in Thunder Bay, Ontario, Canada. Informed by research into the history, function, and construction of grain elevators, this investigation develops an approach to adaptation that would inhabit the interior spaces while preserving the sense of wonder and intrigue inherent in these structures. Using a program defined only as the most basic requirements for habitation, spatial possibilities are investigated to augment the aesthetic, monumental, and mysterious qualities of the structure, without domesticating it.
5

Total quality management : a study of its applications to customer services in a Hong Kong elevator company /

Lai, Po-wah. January 1996 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 114-117).
6

Building international strategic alliances through a network approach /

Tam, Kai-man. January 1998 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1998. / Includes bibliographical references.
7

Use of a sternal elevator to reverse complete airway obstruction secondary to anterior mediastinal mass in an anesthetized child

Linnaus, Maria E., Morray, Jeffrey, Bae, Jae-O, Fraser, Jason D. 05 1900 (has links)
Patients with an anterior mediastinal mass pose significant risk for cardiorespiratory compromise during surgical procedures and general anesthesia. Several techniques have been described to reverse airway obstruction in these patients. In extreme circumstances, patients may require cardiac bypass or extracorporeal membrane oxygenation (ECMO) until definitive treatment of the mass and patient stabilization is achieved. We present a case in which the RulTract (R) system was used for emergency sternal elevation as a bridge to ECMO in acute respiratory collapse in an 11-year-old female with a minimally symptomatic anterior mediastinal mass. (C) 2016 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
8

Building international strategic alliances through a network approach

譚啓文, Tam, Kai-man. January 1998 (has links)
published_or_final_version / Business Administration / Master / Master of Business Administration
9

A study of safety in lift industry

Leung, Shui-cheung, 梁瑞祥 January 1998 (has links)
published_or_final_version / abstract / Real Estate and Construction / Master / Master of Science in Construction Project Management
10

Discrete Event Simulation of Elevator Systems

Desai, Sasi Bharath 01 January 2012 (has links)
The intent of this paper is to present the reader with a simple comparison of two systems of vertical transportation. Vertical transportation is a a relatively new field and is the subject of much interest in today's world. As buildings get taller and real estate becomes more expensive, the need to find a quick, efficient system with a small footprint becomes important. By performing a simulation and subjecting the two systems under study to similar traffic conditions, one can determine the effectiveness of one system relative to the other. Additionally, we look at the effects of changing various system attributes to gain a better understanding of the primary drivers of average travel time.

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