Analysis of Drive Shaft Speed Variations in a Scotch Yoke Mechanism

1982 ◽  
Vol 104 (1) ◽  
pp. 239-246 ◽  
Author(s):  
J. L. Wiederrich
Keyword(s):  
Practical Importance ◽  
Drive Shaft ◽  
Constant Speed ◽  
Shaft Speed ◽  
Flexible Coupling ◽  
Harmonic Content ◽  
Common Drive ◽  
Scotch Yoke Mechanism

Two analyses are presented for determining the drive shaft speed variations in a scotch yoke mechanism. The first analysis determines the speed variations when the mechanism is rigidly connected to a motor having a quadratic speed versus torque characteristic. The second analysis determines the speed variations when the mechanism is connected to a constant speed source through a flexible coupling. Together these models represent the two most common drive configurations. The results are of practical importance since they can be used in the preliminary calculations necessary in either the design of a main drive or the diagnosis of a drive problem in an existing machine. The methods are also of theoretical importance since they may be extended to the analysis of mechanisms having a greater harmonic content than the simple scotch yoke mechanism.

Optimization for Harmonics Reduction and Path Generation of Linkage Mechanisms

2003 ◽  
Vol 03 (03) ◽  
pp. 435-442 ◽  
Author(s):  
Zhongfan Yuan ◽  
Yi Min Wu
Keyword(s):  
Optimal Design ◽  
Dynamic Characteristics ◽  
Fuzzy Theory ◽  
Present Approach ◽  
Constant Speed ◽  
Path Generation ◽  
Servo Motor ◽  
Harmonic Content ◽  
Hybrid Mechanism

The optimal design of linkage mechanisms for path generation and motions with reduced harmonic content is investigated. The designs are carried out using a two-objective optimizer based on the fuzzy theory. As an illustration, the present approach is applied to the optimization of a five-bar hybrid mechanism driven by a constant speed motor and a servo motor. The dynamic characteristics of the servo motor are improved, as the harmonics in the servo motion are reduced.

Designing Self-Balanced Spatial Mechanisms

2015 ◽  
Vol 770 ◽  
pp. 328-332
Author(s):  
I.K. Bituev
Keyword(s):  
Mechanical Systems ◽  
Drive Shaft ◽  
Mutual Arrangement ◽  
Single Loop ◽  
Spatial Mechanisms ◽  
Common Drive

This paper summarises the results obtained from a study of the conditions required to achieve self-balanced mechanical systems. The design self-balanced systems composed of single-loop spatial mechanisms with a common drive shaft, is reviewed. The paper explains how the problems are solved by selecting the relative angles of the mechanism's cranks, their number and mutual arrangement. The resulting self-balancing criteria enable the construction of spatial mechanical systems with predetermined levels of residual imbalance.

Practical Importance of Spatial Resolution and Analytical Sensitivity in AEM X-ray Microanalysis

1990 ◽  
Vol 48 (2) ◽  
pp. 432-433
Author(s):  
J. Zhang ◽  
D.B. Williams ◽  
J.I. Goldstein
Keyword(s):  
Spatial Resolution ◽  
Practical Importance ◽  
Beam Current ◽  
Specimen Thickness ◽  
Analytical Sensitivity ◽  
Related Factors ◽  
X Ray ◽  
Probe Size ◽  
Excitation Volume ◽  
Two Parameters

Analytical sensitivity and spatial resolution are important and closely related factors in x-ray microanalysis using the AEM. Analytical sensitivity is the ability to distinguish, for a given element under given conditions, between two concentrations that are nearly equal. The analytical sensitivity is directly related to the number of x-ray counts collected and, therefore, to the probe current, specimen thickness and counting time. The spatial resolution in AEM analysis is determined by the probe size and beam broadening in the specimen. A finer probe and a thinner specimen give a higher spatial resolution. However, the resulting lower beam current and smaller X-ray excitation volume degrade analytical sensitivity. A compromise must be made between high spatial resolution and an acceptable analytical sensitivity. In this paper, we show the necessity of evaluating these two parameters in order to determine the low temperature Fe-Ni phase diagram.A Phillips EM400T AEM with an EDAX/TN2000 EDS/MCA system and a VG HB501 FEG STEM with a LINK AN10 EDS/MCA system were used.

Contrasts of planar defects in reflection electron microscopy

1993 ◽  
Vol 51 ◽  
pp. 1004-1005
Author(s):  
Feng Tsai ◽  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Surface Defects ◽  
Practical Importance ◽  
Theoretical Treatment ◽  
Crystal Surfaces ◽  
Planar Defects ◽  
Surface Steps ◽  
Surface Reconstructions ◽  
Domain Boundaries ◽  
Reflection Electron Microscopy

Reflection electron microscopy (REM) has been used to study surface defects such as surface steps, dislocations emerging on crystal surfaces, and surface reconstructions. However, only a few REM studies have been reported about the planar defects emerging on surfaces. The interaction of planar defects with surfaces may be of considerable practical importance but so far there seems to be only one relatively simple theoretical treatment of the REM contrast and very little experimental evidence to support its predications. Recently, intersections of both 90° and 180° ferroelectric domain boundaries with BaTiO3 crystal surfaces have been investigated by Tsai and Cowley with REM.The REM observations of several planar defects, such as stacking faults and domain boundaries have been continued by the present authors. All REM observations are performed on a JEM-2000FX transmission electron microscope. The sample preparations may be seen somewhere else. In REM, the incident electron beam strikes the surface of a crystal with a small glancing angle.

How to speed up to be in time: Action-judgment dissociations in children and adults

2004 ◽  
Vol 63 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Friedrich Wilkening ◽  
Claudia Martin
Keyword(s):  
Rating Scale ◽  
Constant Speed ◽  
Linear Condition ◽  
Speed Up ◽  
Nonlinear Condition ◽  
Speed Change ◽  
Catch Up ◽  
Normative Rule ◽  
Judgment Condition ◽  
Time Linear

Children 6 and 10 years of age and adults were asked how fast a toy car had to be to catch up with another car, the latter moving with a constant speed throughout. The speed change was required either after half of the time (linear condition) or half of the distance (nonlinear condition), and responses were given either on a rating scale (judgment condition) or by actually producing the motion (action condition). In the linear condition, the data patterns for both judgments and actions were in accordance with the normative rule at all ages. This was not true for the nonlinear condition, where children’s and adults’ judgment and also children’s action patterns were linear, and only adults’ action patterns were in line with the nonlinearity principle. Discussing the reasons for the misconceptions and for the action-judgment dissociations, a claim is made for a new view on the development of children’s concepts of time and speed.

JUDICIARY AND JUDICIARY OF UKRAINE IN THE CONTEXT OF THE NATIONAL MENTALITY

2019 ◽  
pp. 88-97
Author(s):  
Oleksandr Byrkovych
Keyword(s):  
Scientific Knowledge ◽  
Practical Importance ◽  
Constitutional Court ◽  
State Institutions ◽  
Radical Reform ◽  
Legal Studies ◽  
National Tradition ◽  
Scientific Institutions ◽  
Legal Foundations ◽  
Constitutional Right

Purpose. The purpose of the article is to identify the fundamental values of the Ukrainian people, on the basis of which not only his mentality, but also all national-state institutions, including institutions of justice and justice, as well as to identify trends of influence of these values on the further development of legal foundations of the judiciary and justice of Ukraine. Method. The methodological basis of the study was the combination of principles and methods of scientific knowledge. For the objectivity of the research, a set of general scientific, special-legal, special-historical and philosophical methods of scientific knowledge was used. Results. At the current stage of reforming the institutions of the judiciary and the judiciary, the notion of fair justice, which is formed on the basis of popular national culture, plays an important role. Given the functioning of the modern Constitutional Court of Ukraine, whose representatives are formed by delegation to the Verkhovna Rada of Ukraine, the President of Ukraine, the Cabinet of Ministers of Ukraine and the judiciary, this institution needs radical reform as it has repeatedly made political rather than constitutional decisions. Scientific novelty. Based on the analysis of the national tradition of justice, it is established that the Constitutional Court should be formed by public organizations, which are formed by legal experts. There are several higher scientific institutions in Ukraine which have departments, constitutional law research institutes. Their representatives should delegate the best experts in the constitutional right to competitive selection to fill vacancies in the constitutional court. Practical importance. The results of the study can be used in further historical and legal studies, preparation of special courses.

Features of labor relations in quarantine conditions

2020 ◽  
pp. 52-58
Author(s):  
Lesja Kosmii
Keyword(s):  
Law Enforcement ◽  
Labor Relations ◽  
Practical Importance ◽  
Functional System ◽  
Labor Rights ◽  
Personnel Decisions ◽  
Labor Legislation ◽  
Foreign Countries ◽  
Legislative Framework ◽  
Work Method

Goal. The purpose of this work is to analyze the norms of the current labor legislation regarding the regulation of the relations between the employee and the employer in the introduction of any restrictions and anti-epidemic measures in the conditions of national quarantine and prevention in such conditions of violations of labor rights of employees. It is important that during the course of the COVID-19 coronary pandemic measures, they were not only effective but also violated human rights, including work. Method. The methodology includes a comprehensive analysis and generalization of available scientific and theoretical material, experience of foreign countries and formulation of relevant conclusions and recommendations. During the research the following methods of scientific knowledge were used: terminological, comparative, functional, system-structural, logical-normative. Results. During the research it was found that the Ukrainian legislature, including foreign experience, was able to respond promptly to the quarantine situation by adopting anti-crisis laws, which did not neglect labor legislation. This is understandable, because in connection with the announcement of quarantine in the whole territory of Ukraine, employers had to make personnel decisions, and the current legislative framework did not clearly regulate the issues that arose. Scientific novelty. The study found that the updating of labor legislation in the area of labor relations regulation during the national quarantine period allows the employer to use certain forms of labor organization, in which the basic labor rights and guarantees of employees can be preserved. Practical importance. The results of the study can be used in law-making and law enforcement activities, as well as by employers in regulating labor relations with employees during the quarantine period.

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