High-torque variator with rocker oscillating mechanism

2021 ◽  
pp. 3-9
Author(s):  
B.V. Pylaev

The design and the theory of calculation of the rocker oscillatory mechanism are presented, which provides an increase in more than 2 times the oscillation range of the oscillating shaft in comparison with the known oscillating mechanisms. The device allows to significantly increase the effectiveness of a high-torque non-frictiontype variator: it increases the variation range, reduces the cost of the design and reduces the metal consumption of the variator. Keywords: adjustable oscillating mechanism, cam non-friction high-torque variator [email protected]

2021 ◽  
Vol 11 (3) ◽  
pp. 62-66
Author(s):  
Oleg G. ORLOV

Various sources of noise in cities and ways to combat them are considered. The effi ciency of two types of acoustic screens is analyzed: single-layer and two-and three-layer. The positive and negative characteristics of various designs of existing acoustic screens are listed. A fundamentally new design of the acoustic screen is described: the panels have a ridge profi le, they are located along the vertical axis of the frame with a step at which the panels above the located ridge cover the top of the lower ridge, the outer surfaces of the panels and their end parts are made of a material that has sound-refl ecting properties, and the inner surfaces of the panels are made of sound-absorbing material. Such an acoustic screen is devoid of the disadvantages inherent in acoustic screens of other structures and is more effi cient. The considered invention allows due to the use of the ridge shape of acoustic panels: prevent the refl ection of sound energy in the direction of noise sources (a small part will be directed upwards); provide almost complete absorption of sound energy as it passes through the channels formed by the ridge panels; provide the same effective protection against noise sources located on both sides of the screen; prevent the formation of snow and ice crust on sound-absorbing surfaces, which ensures the constant eff ectiveness of the screen in diff erent seasons of the year; reduce metal consumption, which will reduce the weight of the structure without reducing its effi ciency and reduce the cost of acoustic screens.


2021 ◽  
Vol 7 (1) ◽  
pp. 99-123
Author(s):  
Nikolai A. Senkin ◽  
Aleksandr S. Filimonov ◽  
Islam M. Khalimbekov ◽  
Angelica I. Kravets ◽  
Dona S. Mitrovska ◽  
...  

Background: As part of student research at St. Petersburg architectural-construction University continues to develop alternative proposals for the creation of a circumferential highway at the boundaries of communication areas of St. Petersburg and Leningrad region. The article presents the results of research works on optimization of routing highways, according to the architectural layout of buildings, transport hubs, to study the effects the pre-tension of the puffs and the guys at the reduction of efforts and deformations of the main elements of the highway, the calculations of the designs of the most high and loaded sea area. The construction of the 8-high-speed transport highway was upgraded due to restrictions related to the reconstruction of Levashovo and Pulkovo airports, the transfer of the capital of the Leningrad region to Gatchina, and linking to the promising metro stations Strelna, Yanino and Kudrovo. The upgraded scheme of the highway is proposed in the form of an open polygon with transport and interchange nodes in the corners and is based on load-bearing trestle structures of arched-cable design that provide the necessary functionality, reliability and safety. Aim: development of a district high-speed transport system on the borders of St. Petersburg and the Leningrad region, based on the widespread use of electric transport, with passenger traffic comparable to the metro line. Materials and Methods: trestle structures are designed for combinations of operating loads, forces and impacts, including consideration of dynamic aspects and non-linearity, using the "SCAD Office" software package. Results: based on the results of variant design, an arch-cable-stayed version with spans of 180 m and 360 m was adopted as a supporting structure according to the metal consumption criterion, which became the basic one for building a highway of overpass design. From an approximate calculation, it follows that the cost of building a highway on land plots (two-track scheme) compared to the construction of the metro, it is expected to be 5-6 times lower, and on the sea sections 3-4 times lower due to high pylons and deep pile foundations. Conclusion: the estimated volume of passenger traffic per day for the two-track high-speed and two-track high-speed highways will be 208 thousand passengers, and 76 million passengers per year, which is quite comparable to this indicator for the metro line.


Author(s):  
James F. Mancuso

IBM PC compatible computers are widely used in microscopy for applications ranging from control to image acquisition and analysis. The choice of IBM-PC based systems over competing computer platforms can be based on technical merit alone or on a number of factors relating to economics, availability of peripherals, management dictum, or simple personal preference.IBM-PC got a strong “head start” by first dominating clerical, document processing and financial applications. The use of these computers spilled into the laboratory where the DOS based IBM-PC replaced mini-computers. Compared to minicomputer, the PC provided a more for cost-effective platform for applications in numerical analysis, engineering and design, instrument control, image acquisition and image processing. In addition, the sitewide use of a common PC platform could reduce the cost of training and support services relative to cases where many different computer platforms were used. This could be especially true for the microscopists who must use computers in both the laboratory and the office.


Author(s):  
H. Rose

The imaging performance of the light optical lens systems has reached such a degree of perfection that nowadays numerical apertures of about 1 can be utilized. Compared to this state of development the objective lenses of electron microscopes are rather poor allowing at most usable apertures somewhat smaller than 10-2 . This severe shortcoming is due to the unavoidable axial chromatic and spherical aberration of rotationally symmetric electron lenses employed so far in all electron microscopes.The resolution of such electron microscopes can only be improved by increasing the accelerating voltage which shortens the electron wave length. Unfortunately, this procedure is rather ineffective because the achievable gain in resolution is only proportional to λ1/4 for a fixed magnetic field strength determined by the magnetic saturation of the pole pieces. Moreover, increasing the acceleration voltage results in deleterious knock-on processes and in extreme difficulties to stabilize the high voltage. Last not least the cost increase exponentially with voltage.


1994 ◽  
Vol 58 (11) ◽  
pp. 832-835 ◽  
Author(s):  
ES Solomon ◽  
TK Hasegawa ◽  
JD Shulman ◽  
PO Walker
Keyword(s):  

1998 ◽  
Vol 138 (2) ◽  
pp. 205-205
Author(s):  
Snellman ◽  
Maljanen ◽  
Aromaa ◽  
Reunanen ◽  
Jyrkinen‐Pakkasvirta ◽  
...  
Keyword(s):  

2004 ◽  
Vol 171 (4S) ◽  
pp. 40-40
Author(s):  
Leslee L. Subak ◽  
Stephen K. Van Den Eeden ◽  
Jeanette S. Brown ◽  
Arona I. Ragins ◽  
Eric Vittinghoff ◽  
...  

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