Lubrication Characteristics of Electric Sliding Contacts Consisting of Rotating Circular Grooved Disk and Stationary Rider With Spherical Surface Under Lubricated Condition

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Satoru Kaneko ◽  
Hiroo Taura ◽  
Ryosuke Fukasawa ◽  
Hitoshi Kanai
Keyword(s):  
Frictional Force ◽  
Spherical Surface ◽  
Disk Surface ◽  
Cross Sectional Area ◽  
Metal Contact ◽  
Sectional Area ◽  
Sliding Contacts ◽  
Cross Sectional ◽  
Oil Film ◽  
Lubricant Oil

Electric sliding contacts are widely used in various electrical components such as for home appliances and automobiles. The purpose of the present study is to improve the performance characteristics of the electric sliding contacts operating under the lubricated condition by the combination of circular grooved disk and rider with a spherical surface. The experimental and theoretical analyses have been carried out to investigate the effect of cross-sectional area of circular grooves provided in the rotating disk surface on the frictional characteristics and the electrical conductivity. The experimental analysis is conducted with a pin-on-disk friction tester to measure the frictional force and the contact voltage between the sliding contacts under the lubricated condition. The oil-film force and the frictional force between the rider and disk are also calculated with the Reynolds equation and they are found to be closely corresponding to the experimental results. The results obtained in the present study show that increasing the cross-sectional area of the circular grooves on the disk extends the operation condition yielding the metal contact to a higher value of the bearing characteristic number S, which is defined by ηU0L0λ/W (η is the lubricant oil viscosity, U0 is the sliding velocity, L0 is the rider arc length in the sliding direction at the middle of radial width, W is the applied load, and λ is the aspect ratio of rider), and also decreases the frictional force at the maximum value of S at which the rider could contact with the disk surface. These are expected since upstream lubricant oil dragged into the contact region tends to easily leak out along the circular grooves, yielding a lower oil-film force between the rider and disk and enhancing the metal contact.

Pelvic Canal Narrowing Caused by Triple Pelvic Osteotomy in the Dog

1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani
Keyword(s):  
Postoperative Complications ◽  
Pelvic Osteotomy ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Canal Width ◽  
Operative Complications ◽  
Post Operative Complications

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.

DETERMINATION OF THE FUNCTION OF THE ROD’S CROSS-SECTIONAL AREA USING VIBRATION EIGENFREQUENCIES

2020 ◽  
Vol 0 (4) ◽  
pp. 19-24
Author(s):  
I.M. UTYASHEV ◽  
◽  
A.A. AITBAEVA ◽  
A.A. YULMUKHAMETOV ◽  
◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Variable Cross ◽  
Sectional Area ◽  
Longitudinal Vibrations ◽  
Cross Sectional ◽  
Method Error ◽  
Various Boundary Conditions ◽  
Elastic Fixation ◽  
Crosssectional Area

The paper presents solutions to the direct and inverse problems on longitudinal vibrations of a rod with a variable cross-sectional area. The law of variation of the cross-sectional area is modeled as an exponential function of a polynomial of degree n . The method for reconstructing this function is based on representing the fundamental system of solutions of the direct problem in the form of a Maclaurin series in the variables x and λ. Examples of solutions for various section functions and various boundary conditions are given. It is shown that to recover n unknown coefficients of a polynomial, n eigenvalues are required, and the solution is dual. An unambiguous solution was obtained only for the case of elastic fixation at one of the rod’s ends. The numerical estimation of the method error was made using input data noise. It is shown that the error in finding the variable crosssectional area is less than 1% with the error in the eigenvalues of longitudinal vibrations not exceeding 0.0001.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

Unequal Probability Scheme for Fruit Count in a Guava Tree

2016 ◽  
Vol 3 (4) ◽  
Author(s):  
R. C. BHARATI
Keyword(s):  
Cross Sectional Area ◽  
Equal Probability ◽  
Sampling Scheme ◽  
Research Station ◽  
Sectional Area ◽  
Cross Sectional ◽  
Unequal Probability ◽  
Selection Probabilities ◽  
Horticultural Research ◽  
Number Of Branches

Data on fruit count corresponding to primary, secondary and tertiary branches of a randomly selected guava CV. Allahabad Safeda were recorded from the guava orchard of Horticultural Research Station, Birauli. The proposed sampling scheme in which the selection probabilities are based on length of braches between two forking points was compared with equal probability(PE), probability proportional to the number of branches(PPN), probability proportional to the cross sectional area (PPA) and probability proportional to volume (PPV) method of sampling and found to be more efficient.

Effect of Early Low-Intensity Exercise on Rat Hind-Limb Muscles Following Acute Ischemic Stroke

2006 ◽  
Vol 7 (3) ◽  
pp. 163-174 ◽  
Author(s):  
Myoung-Ae Choe ◽  
Gyeong Ju An ◽  
Yoon-Kyong Lee ◽  
Ji Hye Im ◽  
Smi Choi-Kwon ◽  
...  
Keyword(s):  
Hind Limb ◽  
Gastrocnemius Muscle ◽  
Exercise Group ◽  
Cross Sectional Area ◽  
Type I ◽  
Sectional Area ◽  
Muscle Type ◽  
Cross Sectional ◽  
Low Intensity ◽  
Low Intensity Exercise

This study examined the effects of daily low-intensity exercise following acute stroke on mass, Type I and II fiber cross-sectional area, and myofibrillar protein content of hind-limb muscles in a rat model. Adult male Sprague-Dawley rats were randomly assigned to 1 of 4 groups (n = 7-9 per group): stroke (occlusion of the right middle cerebral artery [RMCA]), control (sham RMCA procedure), exercise, and stroke-exercise. Beginning 48 hours post-stroke induction/sham operation, rats in the exercise group had 6 sessions of exercise in which they ran on a treadmill at grade 10 for 20 min/day at 10 m/min. At 8 days poststroke, all rats were anesthetized and soleus, plantaris, and gastrocnemius muscles were dissected from both the affected and unaffected sides. After 6 sessions of exercise following acute ischemic stroke, the stroke-exercise group showed the following significant (p < .05) increases compared to the stroke-only group: body weight and dietary intake, muscle weight of affected soleus and both affected and unaffected gastrocnemius muscle, Type I fiber cross-sectional area of affected soleus and both affected and unaffected gastrocnemius muscle, Type II fiber cross-sectional area of the unaffected soleus, both affected and unaffected plantaris and gastrocnemius muscle, Type II fiber distribution of affected gastrocnemius muscle, and myofibrillar protein content of both affected and unaffected soleus muscle. Daily low-intensity exercise following acute stroke attenuates hind-limb muscle atrophy in both affected and unaffected sides. The effects of exercise are more pronounced in the soleus and gastrocnemius as compared to the plantaris muscle.

D of Inner Cross-Sectional Area of Airway Branches in COPD Patients

2019 ◽  
Author(s):  
D. Kinose ◽  
E. Ogawa ◽  
Y. Matsuo ◽  
W. Shigemori ◽  
Y. Uchida ◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Copd Patients

Estimating myofiber cross‐sectional area and connective tissue deposition with electrical impedance myography: a study in D2 ‐mdx mice

2021 ◽  
Author(s):  
Sarbesh R. Pandeya ◽  
Janice A. Nagy ◽  
Daniela Riveros ◽  
Carson Semple ◽  
Rebecca S. Taylor ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Electrical Impedance ◽  
Cross Sectional Area ◽  
Mdx Mice ◽  
Sectional Area ◽  
Cross Sectional
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