A Shelved Structure for the Support of An Electron Optical Column

1970 ◽  
Vol 28 ◽  
pp. 366-367
Author(s):  
P.H. McLaughlin
Keyword(s):  
Electron Source ◽  
Floating Platform ◽  
Supporting Structure

A shelved structure for the support of an electron optical column affords advantages both to the designer and the user. A lens may be removed for cleaning for example, without demounting the remaining lenses. A custom device for another example, may be placed on a shelf, substituting for the standard lens perhaps so that some specialized research may be undertaken. Especially advantageous is a shelved arrangement if the column assembly is designed to hang from a supporting structure such as a gas borne floating platform, as is the case with the system described below.As shown on the schematic, a floating platform (I) supports the electron source apparatus (2) and a U-shaped column support shelf (3). The column support shelf acts as a key for locating and supporting three struts (4) which with nuts (5) support the condenser shelf (6), the objective shelf (7), the upper projector shelf (8), and the lower projector shelf (9).

Structural Engineering of Aluminum Helideck Structure Based on the NORSOK Requirement

2016 ◽  
Author(s):  
Joo Shin Park ◽  
R. Krishna Kishore ◽  
Yeong Su Ha ◽  
Ki Bok Jang
Keyword(s):  
Structural Engineering ◽  
Steel Structures ◽  
Emergency Evacuation ◽  
Offshore Structures ◽  
International Standards ◽  
National Standards ◽  
Floating Platform ◽  
Analysis And Design ◽  
Supporting Structure ◽  
Drilling Rig

Recently, the numbers of large offshore structures and fixed jacket type platforms are rapidly increasing for oil and gas companies. Generally, a shuttle vessel or helicopter is used to access offshore structures such as a fixed platform, floating platform, jack-up rig and so on. The helideck structure should be installed in these offshore structures for landing and taking-off of the helicopter. The helideck structure comprises of pancakes, girders using aluminum materials and supporting steel structures. The helideck structure should be designed to accommodate a safe landing area suitable for the largest and heaviest helicopter that is anticipated to land on the helideck. The helideck and its supporting structure are safety critical elements as a result of their role in emergency evacuation, as well as during normal operations. The codes and standards applicable for the structural design of the helideck will be determined by where the helideck is to be operated and the national jurisdiction governing the installation or vessel of which the helideck will become part. International standards such as ISO(International Organization for Standardization) codes, Eurocodes, or national standards, e.g. BS(British Standards)5950, NORSOK N-004 or AISC(American Institute of Steel Construction) may be specified for detailed design. The objective of this study is to present the results of structural analysis and design that has been performed for a 28.54 meter diameter octagonal standard aluminum helideck with support truss & lower steel support structure of jackup drilling rig based on the NORSOK requirements. The supporting structure is designed to provide the adequate resistance to the external force produced by the design helicopter and environmental conditions.

Optical Properties of HVEM Accelerators

1975 ◽  
Vol 33 ◽  
pp. 180-181
Author(s):  
A. Strojnik ◽  
J.W. Scholl ◽  
V. Bevc
Keyword(s):  
Optical Properties ◽  
Electron Accelerator ◽  
Systematic Investigation ◽  
Electron Source ◽  
High Brightness ◽  
The Past ◽  
Wide Range ◽  
Optical Behavior

The electron accelerator, as inserted between the electron source (injector) and the imaging column of the HVEM, is usually a strong lens and should be optimized in order to ensure high brightness over a wide range of accelerating voltages and illuminating conditions. This is especially true in the case of the STEM where the brightness directly determines the highest resolution attainable. In the past, the optical behavior of accelerators was usually determined for a particular configuration. During the development of the accelerator for the Arizona 1 MEV STEM, systematic investigation was made of the major optical properties for a variety of electrode configurations, number of stages N, accelerating voltages, 1 and 10 MEV, and a range of injection voltages ϕ0 = 1, 3, 10, 30, 100, 300 kV).

A comparative study on the cold type and thermal type field emission guns used in the same electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 58-59
Author(s):  
M. Iwatsuki ◽  
Y. Kokubo ◽  
Y. Harada
Keyword(s):  
Electron Microscope ◽  
Field Emission ◽  
Signal To Noise Ratio ◽  
Electron Source ◽  
Resolving Power ◽  
Optical Source ◽  
Experimental Conditions ◽  
High Brightness ◽  
Illumination System ◽  
Transmission Electron

On accout of its high brightness, small optical source size, and minimal energy spread, the field emission gun (FEG) has the advantage that it provides the conventional transmission electron microscope (TEM) with a highly coherent illumination system and directly improves the resolving power and signal-to-noise ratio of the scanning electron microscope (SEM). The FEG is generally classified into two types; the cold field emission (C-FEG) and thermal field emission gun (T-FEG). The former, in which a field emitter is used at the room temperature, was successfully developed as an electron source for the SEM. The latter, in which the emitter is heated to the temperature range of 1000-1800°K, was also proved to be very suited as an electron source for the TEM, as well as for the SEM. Some characteristics of the two types of the FEG have been studied and reported by many authors. However, the results of the respective types have been obtained separately under different experimental conditions.

Examination of Thermal and Electrical Performance of Cassegrain Concentrator System

2019 ◽  
Vol 8 (6S2) ◽  
pp. 96-98
Keyword(s):  
Stainless Steel ◽  
Great Degree ◽  
Electrical Performance ◽  
Personal Satisfaction ◽  
The Sun ◽  
Supporting Structure ◽  
Apex Point ◽  
Control Water ◽  
Working Liquid ◽  
Made In

The sun oriented power (SP) is a one of a kind renewable vitality innovation. SP frameworks can give control, water warming and water decontamination in one unit. This innovation will be to a great degree accommodating in enhancing the personal satisfaction for some individuals around the globe who do not have the vitality expected to carry on with a sound life. A financial allegorical dish sort Cassegrain concentrating framework was created at the foundation of Energy Studies, Anna University Chennai. An old microwave media transmission reception apparatus having a paraboloidal shape made in aluminum frames an essential reflector which guarantees effortlessness of generation and operation. The essential concentrator was settled with mirror cleaned stainless steel with reasonable cement .The optional concentrator is inward mirror .Suitable supporting structure was developed for supporting the cassegrain concentrator. Double hub following framework is mounted for adjusting the concentrator to azimuth and apex point by utilizing DC engine and direct actuator individually. Water goes about as working liquid to expel warm from .The tank is protected with thermocol material upheld with wooden structure on all sides to maintain a strategic distance from convection misfortunes. The material Cost for the framework was Rs 15000

Spar Floating Platform: Numerical Analysis and Comparison with Data

1997 ◽  
Author(s):  
Alok K. Jha
Keyword(s):  
Numerical Analysis ◽  
Floating Platform

EFFECT OF DIFFERENT DENTURE BASE MATERIAL ON THE SUPPORTING STRUCTURE OF PARTIALLY COVERAGE MAXILLARY IMPLANT RETAINED OVERDENTURE

2017 ◽  
Vol 63 (4) ◽  
pp. 3343-3349
Author(s):  
Nora Sheta ◽  
Shaimaa Lotfy
Keyword(s):  
Base Material ◽  
Denture Base ◽  
Supporting Structure

Study of Seismic Design Method for Slope Supporting Structure of Soil Nailing

2013 ◽  
Vol 353-356 ◽  
pp. 2073-2078
Author(s):  
Tian Zhong Ma ◽  
Yan Peng Zhu ◽  
Chun Jing Lai ◽  
De Ju Meng
Keyword(s):  
Seismic Design ◽  
Calculation Method ◽  
Retaining Wall ◽  
Earth Pressure ◽  
Calculation Model ◽  
Soil Nailing ◽  
Case Record ◽  
Analysis And Design ◽  
Supporting Structure ◽  
Earthquake Action

Slope anchorage structure of soil nail is a kind of economic and effective flexible slope supporting structure. This structure at present is widely used in China. The supporting structure belong to permanent slope anchorage structure, so the design must consider earthquake action. Its methods of dynamical analysis and seismic design can not be found for the time being. The seismic design theory and method of traditional rigidity retaining wall have not competent for this new type of flexible supporting structure analysis and design. Because the acceleration along the slope height has amplification effect under horizontal earthquake action, errors should be induced in calculating earthquake earth pressure using the constant acceleration along the slope height. Considering the linear change of the acceleration along the slope height and unstable soil with the fortification intensity the influence of the peak acceleration, the earthquake earth pressure calculation formula is deduced. The soil nailing slope anchorage structure seismic dynamic calculation model is established and the analytical solutions are obtained. The seismic design and calculation method are given. Finally this method is applied to a case record for illustration of its capability. The results show that soil nailing slope anchorage structure has good aseismic performance, the calculation method of soil nailing slope anchorage structure seismic design is simple, practical, effective. The calculation model provides theory basis for the soil nailing slope anchorage structure of seismic design. Key words: soil nailing; slope; earthquake action; seismic design;

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