The Tolerance Coordination Design Method of Related Feature and Datum Features When Applying Material Condition

Author(s):  
Yuguang Wu ◽  
Zhiqian Mei

When the datum features apply a material condition, the tolerance of a related feature must coordinate with its datum features. The tolerance coordination design of the related feature with its datum features is an important issue; an uncoordinated tolerance will give rise to an unnecessarily tight tolerance of a target geometrical feature or an invalid application of the material condition. In this paper, a coordination design method is proposed. The notion of the shift tolerance is used to establish the coordination relationship of the tolerance between the related feature and its datum features. The calculation mechanism of the shift tolerance for two datum features applying a material condition is described. To calculate the shift tolerance of the datum features, the datum feature simulator is used to construct the measurement coordinate system and the design coordinate system. For the different combination of two datum features applying a material condition, the relative motion of the design coordinate system with respect to the measurement coordinate system is represented by the parallel-crank mechanism, and the length of the crank is used to calculate the shift tolerance. Based on the shift tolerance, two criteria of the tolerance design at applying material condition are studied, one is the coordination guideline for the geometric tolerance of the related feature and the dimensional tolerance of the datum feature; the other criterion is the coordination guideline for the dimension tolerance between two datum features. Finally, two case studies are introduced to verify reasonableness of the proposed criteria and method.

Electronics ◽  
2021 ◽  
Vol 10 (15) ◽  
pp. 1856
Author(s):  
Yen-Chung Chiang ◽  
Juo-Chen Chen ◽  
Yu-Hsin Chang

In a radio frequency (RF) system, it is possible to use variable inductors for providing tunable or selective frequency range. Variable inductors can be implemented by the microelectromechanical system (MEMS) process or by using transistors as switches to change the routing of coils or coupling quantities. In this paper, we investigated the design method of a variable inductor by using MOS transistors to switch the main coil paths and the secondary coupled coils. We observed the effects of different metal layers, turn numbers, and layout arrangements for secondary-coupled coils and compared their characteristics on the inductances and quality factors. We implemented two chips in the 0.18 m CMOS process technology for each kind of arrangement for verification. One inductor can achieve inductance values from about 300 pH to 550 pH, and the other is between 300 pH and 575 pH, corresponding to 59.3% and 62.5%, respectively, inductance variation range at 4 GHz frequency. Additionally, their fine step sizes of the switched inductances are from 0.5% to 6% for one design, and 1% to 12.5% for the other. We found that both designs achieved a large inductance tuning range and moderate inductance step sizes with a slight difference behavior on the inductance variation versus frequency.


During the last few years of his life Prof. Simon Newcomb was keenly interested in the problem of periodicities, and devised a new method for their investigation. This method is explained, and to some extent applied, in a paper entitled "A Search for Fluctuations in the Sun's Thermal Radiation through their Influence on Terrestrial Temperature." The importance of the question justifies a critical examination of the relationship of the older methods to that of Newcomb, and though I do not agree with his contention that his process gives us more than can be obtained from Fourier's analysis, it has the advantage of great simplicity in its numerical work, and should prove useful in a certain, though I am afraid, very limited field. Let f ( t ) represent a function of a variable which we may take to be the time, and let the average value of the function be zero. Newcomb examines the sum of the series f ( t 1 ) f ( t 1 + τ) + f ( t 2 ) f ( t 2 + τ) + f ( t 3 ) f ( t 3 + τ) + ..., where t 1 , t 2 , etc., are definite values of the variable which are taken to lie at equal distances from each other. If the function be periodic so as to repeat itself after an interval τ, the products are all squares and each term is positive. If, on the other hand, the periodic time be 2τ, each product will be negative and the sum itself therefore negative. It is easy to see that if τ be varied continuously the sum of the series passes through maxima and minima, and the maxima will indicated the periodic time, or any of its multiples.


Author(s):  
John F. McGrew

This paper discusses a case study of a design and evaluation of a change management system at a large Telecommunications Corporation. The design and evaluation were done using the facilitated genetic algorithm (a parallel design method) and user decision style analysis. During the facilitated genetic algorithm the design team followed the procedure of the genetic algorithm. Usability was evaluated by applying user decision style analysis to the designed system. The design is compared with an existing system and with one designed by an analyst. The change management system designed by the facilitated genetic algorithm took less time to design and decision style analysis indicated it would be easier to use than the other two systems.


1944 ◽  
Vol 90 (380) ◽  
pp. 753-760 ◽  
Author(s):  
E. Stengel

In recent years important additions to the knowledge of the symptomatology in cases with involvement of the parietal lobe have been made. Both constructional apraxia (Kleist, 1922) and Gerstmann's syndrome, consisting of finger-agnosia, disturbance of right-left orientation, agraphia and acalculia (1924) have been related to lesions of the angular gyrus of the dominant hemisphere. Before the description of those symptoms, a loss of spatial orientation had been described in cases with lesions of the same localization. Balint (1910), Riddoch (1917), and others had observed that symptom in single cases, but the most comprehensive description was given by Gordon Holmes (1918), who studied it in a case-material of war injuries. When Holmes and his co-workers published their observations, constructional apraxia and Gerstmann's syndrome were still unknown. Loss of spatial orientation as a fully developed symptom is rare, while the other two disorders are not uncommon. For this reason the psychopathological relationship of those symptoms is still insufficiently understood. The following case offers an opportunity for studying the problem:


1990 ◽  
Vol 7 (4) ◽  
pp. 329-346 ◽  
Author(s):  
William McTeer ◽  
James E. Curtis

This study examines the relationship between physical activity in sport and feelings of well-being, testing alternative interpretations of the relationship between these two variables. It was expected that there would be positive relationships between physical activity on the one hand and physical fitness, feelings of well-being, social interaction in the sport and exercise environment, and socioeconomic status on the other hand. It was also expected that physical fitness, social interaction, and socioeconomic status would be positively related to psychological well-being. Further, it was expected that any positive zero-order relationship of physical activity and well-being would be at least in part a result of the conjoint effects of the other variables. The analyses were conducted separately for the male and female subsamples of a large survey study of Canadian adults. The results, after controls, show a modest positive relationship of physical activity and well-being for males but no such relationship for females. The predicted independent effects of the control factors obtained for both males and females. Interpretations of the results are discussed.


2015 ◽  
Vol 1120-1121 ◽  
pp. 1109-1114
Author(s):  
Xin Lei ◽  
Hui Huang ◽  
S.P. Wen

This study investigated the mechanical properties and microstructures of Er-containing Al–Mg alloys. The research found that the H114-T sheet of Er-containing Al–Mg alloys showed a relative good comprehensive performance in mechanical properties. With the special rolling and heat treatment process, this H114-T sheet showed different morphology of microstructures with the other sheets in Er-containing Al–Mg alloys. Grains in H114-T sheet performed irregular shape polygon, a number of subgrains appeared in grains, the amount of dislocations in grains decreased. H114-T sheet possessed a lot of Copper texture, this may be one of important factors influenced the mechanical properties.


1956 ◽  
Vol 23 (1) ◽  
pp. 120-125 ◽  
Author(s):  
J. Czulak ◽  
Jill Naylor

A lysogenic culture, prepared in the laboratory from a strain of Streptococcus lactis, was used as a cheese starter in commercial factories. It was attacked in turn by two other unrelated phage races. The lysogenic condition, which involved slight morphological and physiological changes, persisted in the subsequent forms resistant to one or both the new phage races. Acquired resistance to any one of the three phages did not protect the culture from the other two phages.In nature such interactions between phage races and lactic acid bacteria must be constantly taking place, giving rise to similarly related strains.Two of the three phage races produced spreading haloes around their plaques due to a lysin released during phage action. The lysin may also interfere with the survival of secondary growth after attack by these phage races. Production of this type of lysin is thus a property of the phage race and not of the bacterial strain.


PEDIATRICS ◽  
1962 ◽  
Vol 30 (6) ◽  
pp. 909-916
Author(s):  
Herbert I. Goldman ◽  
Samuel Karelitz ◽  
Hedda Acs ◽  
Eli Seifter

One hundred four healthy premature infants, of birth weight 1,000 to 1,800 gm, were fed one of five feedings: (1) human milk; (2) human milk plus 13 meq/l of sodium chloride; (3) human milk plus 13 meq/l of sodium chloride and 18 meq/l of potassium chloride; (4) a half-skimmed cows milk formula; and (5) a partially-skimmed vegetable oil, cows milk formula. The infants fed any of the three human milk formulas gained weight at a slower rate than the infants fed either of the two cows milk formulas. Infants whose diets were changed from unmodified human milk to the half-skimmed cows milk gained large amounts of weight, and at times were visibly edematous. Infants whose diets were changed from the human milks with added sodium chloride, to the half-skimmed cows milk, gained lesser amounts of weight and did not become edematous. The infants fed the two cows milk diets gained similar amounts of weight, although one diet provided 6.5 gm/kg/day, the other 3.1 gm/kg/day of protein.


Lampas ◽  
2019 ◽  
Vol 52 (4) ◽  
pp. 437-452
Author(s):  
Gerard Boter

Summary The present article discusses three hotly debated interpretational issues in Diotima´s speech in Plato´s Symposium. The first of these is the relationship of Diotima´s speech to other dialogues, such as the Phaedo and the Republic, with regard to the immortality of the soul. It is argued that there is no discrepancy at all, because the immortality of the soul does not play any role in the Symposium. The second issue is the nature of the three classes of posterity: biological, spiritual and philosophical. Whereas the posterity of the first two classes can be relatively easily defined, the character of the philosopher´s posterity, ‘true virtue’, remains rather vague. It may consist in dialectical teaching of the Idea of Beauty by Socrates. Thirdly, it is argued that the philosopher´s immortality differs only gradually from the immortality of the other two classes, that is, the philosopher as a man only survives by means of his posterity.


2021 ◽  
pp. 252-268
Author(s):  
V. V. Dyachkov ◽  

The paper deals with the grammaticalization problems in Tomo Kan (Dogon family, Niger-Congo) and, in particular, with the diachronic relationship of polypredicative constructions and TAM markers. Dogon languages are characterized by TAM systems that seem to be dia-chronically unstable since markers with a similar range of meanings go back to different lexi-cal sources in different languages of the family. TAM markers are apparently associated with polypredicative constructions, which are very common in Dogon and preserve some of their morphosyntactic properties. At the same time, Dogon languages are characterized by complex tonal changes triggered not only by phonological context but also by the syntactic position of constituents. These tonal changes, frequently referred to as tonosyntax, accompany the formation of polypredicative constructions and other syntactic phenomena. A thorough inves-tigation of Tomo Kan TAM markers shows their tonosyntactic properties to resemble those of polypredicative constructions. Moreover, assuming that tonosyntax of polypredicative con-structions triggers certain tonal contour overlays, one can account for tonal alternations ob-served in TAM forms which would have been left otherwise unexplained. However, the anal-ysis also reveals that at least two classes of TAM forms must be distinguished in Tomo Kan: one of them inherits the tonosyntax of polypredicative constructions while the other does not. A hypothesis is put forward that the latter class has a different source of grammaticalization and is probably associated with verb stem incorporation rather than with polypredication. Methodologically, the paper shows a critical role of tonology in the analysis of grammaticalization processes in tonal languages.


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