Effects of loading adjustment on the reliability degradation of composites

2011 ◽  
Vol 18 (1-2) ◽  
pp. 61-67
Author(s):  
Chung-Ling Chen ◽  
Kuo-Shong Wang
Keyword(s):  
Residual Strength ◽  
Failure Time ◽  
Transition Period ◽  
Strength Distribution ◽  
Low Level ◽  
Time Period ◽  
The Mean ◽  
Two Parameters ◽  
The Relationship ◽  
Good Agreement

AbstractThis paper defines two parameters to describe the effects of fatigue load adjustment on the reliability degradation of composites. The transition period, n2a, indicates the free failure time period from the instant of high-low adjustment until the residual strength distribution meets the low-level stress. The reliability drop, ∣ΔR∣, is shown at the instant of low-high adjustment. Based on the strength-life equal rank assumption, a typical Yang model of the residual strength is considered to derive these two items by retrieving the residual strength distributions to the corresponding initials. The predicted parameters are verified to be in good agreement with the Monte Carlo simulation of fatigue failure. It is found that n2a increases dramatically as the reliability Ra at which the stress level changes, in the range of 1>Ra>0.95. The relationship between ∣ΔR∣ and Ra exhibits a parabolic-like curve with a peak near the mean cycles to failure of the process at low-level stress.

P3754Comparison of the transdermal bisoprolol patch with the oral bisoprolol fumarate administration as a therapeutic agent for idiopathic frequent premature ventricular contractions

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Shinohara ◽  
R Wada ◽  
K Akitsu ◽  
T Kinoshita ◽  
H Yuzawa ◽  
...  
Keyword(s):  
Therapeutic Agent ◽  
Group Differences ◽  
Night Time ◽  
Premature Ventricular Contractions ◽  
Duration Of Action ◽  
Time Period ◽  
Significant Difference ◽  
The Mean ◽  
Initiation Of Therapy ◽  
The Relationship

Abstract Background The transdermal bisoprolol patch (TB) was designed to maintain a sustained concentration of bisoprolol in plasma by higher trough concentration than the oral bisoporolol fumarate administration (OB). It is unclear whether the TB is as effective in treating idiopathic premature ventricular contractions (PVCs) as the OB. Purpose We compared the efficacy between the TB and OB in treating idiopathic PVCs while considering their duration of action. Methods Among 198 patients with a PVC count of ≥3,000 beats/24 hours, 84 patients were divided into groups treated with TB 4mg (n=50) or OB 2.5mg (n=34). The PVCs were divided into positive heart rate (HR)-dependent PVCs (P-PVCs) and non-positive HR-dependent PVCs (NP-PVCs) based on the relationship between the hourly PVCs density and hourly mean HR. To evaluate the efficacy, PVC counts by 24-hour Holter electrocardiograms were measured at baseline and at 1 month after the initiation of the therapy. Results There were no significant between-group differences for the mean HR, PVC count, or type of PVCs. Both the TB (from 16,692±9,737 to 10,442±10,711 beats/24 hours, P<0.001) and OB (from 19,633±16,298 to 9,235±12,124 beats/24 hours, P<0.001) significantly decreased the total PVC count after the initiation of therapy, and a comparison between the two drugs showed no significant difference (P=0.46). In the P-PVC group, both the TB and OB significantly decreased the total PVC count (P<0.001, P=0.022 respectively), PVC count during the day-time (P<0.001, P=0.030 respectively), and PVC count during the night-time (P=0.0038, P=0.022 respectively). In contrast, in the NP-PVC group, neither the TB nor OB made any significantly change in the total PVC count (P=0.079, P=0.10 respectively), PVC count during the day-time (P=0.35, P=0.12 respectively), or PVC count during the night-time (P=0.11, P=0.12 respectively). The TB exhibited a significant reduction during each time period regarding the changes within 24-hours in the P-PVC count from baseline, while the OB did not significantly reduce the P-PVC count from baseline during each time period between 0 and 5 o'clock. Conclusions Compared with the OB, the TB could be used with the same efficacy for reducing the PVC count. The TB could be a more useful therapeutic agent for idiopathic P-PVCs during a 24-hour period than the OB.

scholarly journals The Relationship Between Defense Mechanisms and Nurses’ Occupational Burnout: A Cross-Sectional Study

2020 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Forouzan Elyasi ◽  
Seyed Mohammad Hosseininejad ◽  
Parisa Islami Parkoohi ◽  
Mahsa Kamali ◽  
Marzieh Azizi ◽  
...  
Keyword(s):  
Significant Relationship ◽  
Defense Mechanisms ◽  
Maslach Burnout Inventory ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Occupational Burnout ◽  
Cross Sectional ◽  
Low Level ◽  
The Mean ◽  
The Relationship

Background: Occupational burnout is a psychological syndrome that occurs in response to chronic stress in the workplace. Nowadays, it is known as one of the most important consequences of occupational stress. Defense mechanisms may also affect occupational burnout. Objectives: Since burnout is an important factor influencing the productivity of nurses, this study was conducted to investigate the relationship between the defense mechanisms and occupational burnout among nurses in the educational hospitals of an urban area in Iran. Methods: This descriptive cross-sectional study was conducted on 318 nurses who had at least one-year of work experience in four educational hospitals in Sari city, Iran, in 2018. Sampling was performed using the proportional stratified sampling method. The data were collected by the Maslach Burnout Inventory (MBI) scale, psychological Defense Styles questionnaire (DSQ-40), and a demographic questionnaire. Data were analyzed using descriptive and inferential statistics via the SPSS software V.20. Results: A total of 318 nurses were studied, 13 (4.1%) of the nurses had a burnout. The mean score of the dimension of emotional exhaustion (EE) was 17.49, in the dimension of depersonalization (DP) it was 5.42, and in the dimension of personal achievement (PA) it was 31.58. They indicated a low level of occupational burnout, and the mean scores of FE, DP, and PA subscales indicated a low level of occupational burnout. The use of more mature defense mechanisms had a significant negative correlation with the increase of the EE score (rho = -0.210, P < 0.001), but no significant relationship was reported with other aspects of burnout. Increased use of immature defense mechanisms had a direct correlation with the increase in the score of DP (rho = 0.255 and P < 0.001), but had a significant inverse relationship with the PA score (rho = -0.238 and P < 0.001) and no significant relationship with EE (P = 0.627). No significant relationship was found between the use of neurotic defense mechanisms and burnout dimensions (PEE = 0.119, PDP = 0.174, and PPA = 0.127). Conclusions: Since there is a significant relationship between defense mechanisms and occupational burnout, using the components of defense mechanisms in job interviews can lead to choosing appropriate nurses to perform different tasks in different settings, in accordance with individual and psychological characteristics. Also, teaching problem-solving skills, stress management, and useful information can improve defense mechanisms, nurses’ job performance, and patient satisfaction.

Volume distribution of Evans blue dye and iodinated albumin in the dog

1963 ◽  
Vol 205 (2) ◽  
pp. 351-356 ◽  
Author(s):  
R. A. Huggins ◽  
E. L. Smith ◽  
S. Deavers
Keyword(s):  
Plasma Volume ◽  
Blue Dye ◽  
Volume Distribution ◽  
Reasonable Estimate ◽  
Time Period ◽  
Straight Line ◽  
Point Curve ◽  
The Mean ◽  
The Difference ◽  
Good Agreement

Three hundred seventy-two morphine-pentobarbitalized dogs were divided into groups according to the sampling time after injections of T-1824, I131, or both simultaneously. The data were programmed for digital computer analysis. In dogs receiving the tags separately the mean plasma volume was 50.0 ± 0.63 and 49.8 ± 0.72 ml/kg for dye and I131, respectively. Three simultaneous T-1824 and I131-tagged albumin injections were made with samples taken at 5, 10, 15, 20, 30, 45, and 60 min after each injection. Mixing was complete at approximately 5 min. Mean plasma volumes were 52.5 ± 2.24 ml/kg for the dye and 49.3 ± 1.69 ml/kg for the I131. The difference was not significant. In this group there was a good agreement between plasma volumes when calculated from the seven point curve or from three points only, indicating that all points were part of the same straight line. Therefore, a shorter time period with fewer samples is advantageous. Furthermore, when maximum accuracy is not required, the 5-min sample gives a reasonable estimate of plasma volume.

scholarly journals The Relationship between Parental Involvement and the Students’ Achievement at the Eighth Grade Students of MTs Negeri 1 Makassar

2018 ◽  
Vol 5 (2) ◽  
pp. 22-35
Author(s):  
Sitti Maryam Hamid
Keyword(s):  
Decision Making ◽  
Parental Involvement ◽  
Eighth Grade ◽  
Low Level ◽  
Eighth Grade Students ◽  
The Mean ◽  
English Achievement ◽  
Learning At Home ◽  
The Relationship ◽  
Academic Year

The objective of this research were to analyze: (1) parental involvement in the students’ achievement at the Eighth Grade Students of MTsNegeri 1 Makassar. (2) the relationship between parental involvement and students’ achievement at the eighth grade students of MTsNegeri 1 Makassar.The researcher used descriptive correlation research. There were two variables in this research, namely parental involvement (variable X) and the students’ English achievement (variable Y). The technique of collecting data used questionnaire and documentation. The questionnaire consisted of 24 items. The sample of this research was 42 students.The result of the research showed that forms of parental involvement are found at the eighth grade of MTsNegeri 1 Makassar, the mean score of parenting was 3.20, communicating was 2.76, volunteering was 2.43, learning at home was 2.49, decision making was 2.78, collaborating with community was 2.53, and the total of the mean score was 16.19. It means that  parental involvement of the eighth grade students of MTsNegeri 1 Makassar is low level. Based on the result of the research, it showed that there was a relationship between parental involvement and students’ English achievement at the eighth grade students of MTsNegeri 1 Makassar in Academic Year of 2018/2019 because r = 0,125.

Effect of electrical stimulation of the crossed olivocochlear bundle on temporary threshold shifts in auditory sensitivity. II. Dependence on the level of temporary threshold shifts

1988 ◽  
Vol 60 (2) ◽  
pp. 569-579 ◽  
Author(s):  
R. Rajan
Keyword(s):  
Sound Pressure ◽  
Standard Stimulus ◽  
Detailed Examination ◽  
Low Level ◽  
Olivocochlear Bundle ◽  
Summating Potential ◽  
Site Of Action ◽  
Two Parameters ◽  
The Relationship ◽  
Maximum Threshold

1. This report presents a more detailed examination of crossed olivocochlear bundle (COCB) effects on temporary threshold shifts (TTS). The principal aim was to establish the details of the relationship between the effects of continuous COCB stimulation and the TTS caused by various exposures. Initially, in various groups, different intensities of a 1-min exposure were presented with or without COCB stimulation. Stimulation at any particular rate caused greatest reductions in TTS to occur for the higher intensity exposures than for the lower intensity ones. Thus COCB stimulation at 140 pulses/s reduced maximum threshold losses by the following amounts: 13.33 [106 dB sound pressure level (SPL) exposure], 13.29 (103 dB SPL exposure), 8.9 (101 dB SPL exposure), and 0.77 dB (97 dB SPL exposure). 2. The effect of COCB stimulation was also examined on a shorter duration (30 s) exposure causing TTS intermediate between that due to 1-min exposure at 97 dB SPL and that at 101 dB SPL. Reductions in TTS to the shorter duration exposure were not obtained with COCB stimulation at 140 pulses/s but only when the rate was increased to 260/s. 3. Thus COCB stimulation at any particular rate caused greatest reductions in TTS when the exposure would have caused a large amount of TTS, regardless of the intensity or duration of exposure. These two parameters of the exposure could be traded to provide a level of TTS that would be affected by a standard COCB stimulus. Low-level exposures that caused only small amounts of TTS were not affected by the standard COCB stimulus. As the level of the exposure, and therefore, the ensuing TTS, increased (with increased duration or intensity of exposure), the standard stimulus had greater effects. Increasing the rate of pulses in the COCB stimulus resulted in the low-level exposures now being affected. Even at the higher rate, greatest reductions in TTS were obtained when the exposure would have resulted in high levels of TTS. 4. In an attempt to determine the site of action of the continuous COCB stimulus the endocochlear potential (EP) and the summating potential (SP) were recorded from scala media of the basal turn while applying COCB stimuli similar to those used in the TTS experiments. Although the continuous COCB stimulus caused the traditional changes in the EP and SP associated with COCB stimulation with pulsed short electrical trains, these changes adapted quite rapidly and did not persist for the amount of time shown to be necessary for full reductions in TTS to be obtained.(ABSTRACT TRUNCATED AT 400 WORDS)

A Time–Motion Analysis of Elite Solo Synchronized Swimming

2008 ◽  
Vol 3 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Teresa Alentejano ◽  
Dru Marshall ◽  
Gordon Bell
Keyword(s):  
Horizontal Distance ◽  
Time Motion ◽  
Significant Relationships ◽  
Time Period ◽  
Synchronized Swimming ◽  
Face Immersion ◽  
The Mean ◽  
The Times ◽  
The Relationship ◽  
Analysis Of Performance

Purpose:To determine the total amount and relative time periods of face immersion (FI) in a synchronized swimming solo routine and the relationship between FI, distance covered, and the technical-merit score of the 11 top Canadian soloists at a synchronized swimming national championship (mean age 20 ± 1.8 y, height 173.3 ± 4.1 cm, and body mass 58.3 ± 4 kg).Methods:Videotape and timing of solo performances combined with manual tracking of pool patterns.Results:Analysis of performance revealed that an average of 18 FI periods, mean of 6.8 s, were performed for an average total time of 133.7 ± 27.1 s (range 102.2 to 199.8 s). The average longest FI time period was 25.45 ± 6.2 s (range 18.18 to 38.72 s), and most (10/11) of these were in the first third of the solo. The mean total horizontal distance covered was 57.61 ± 6.84 m (range 48.61 to 68.2 m), and the total horizontal distance covered relative to time was 0.276 ± 0.034 m/s (range 0.235 to 0.340 m/s). No significant relationships were found between any of the FI periods and the distance covered or between the technical-merit score and FI periods. Each solo contained 6 to 8 underwater sequences, none of which were longer than 40 seconds, the cutoff deemed dangerous by FINA (Fédération Internationale de Natation).Conclusion:This study shows that the times underwater for solos in Canada are within safety limits recommended by FINA and that judging in Canada is not related to underwater periods of swimming.

Measurements of the mean force on a particle near a boundary in turbulent flow

1988 ◽  
Vol 187 ◽  
pp. 451-466 ◽  
Author(s):  
D. Hall
Keyword(s):  
Boundary Layer ◽  
Surface Roughness ◽  
Lift Force ◽  
Smooth Surface ◽  
Small Particles ◽  
Fluid Boundary ◽  
The Mean ◽  
Lift Forces ◽  
The Relationship ◽  
Good Agreement

The transport of particles through gaseous systems is controlled by three factors: their arrival to the surface; whether or not they bounce upon impact; and when (if ever) they are resuspended from the surface. One of the parameters required in determining whether or not a particle is suspended is the lift force acting on the particle. We demonstrate that the fluid lift forces acting on particles as small as 1 μm in diameter can be modelled by particles of several mm in diameter. However, the forces involved in modelling such small particles are around 10−8 N, which is several orders of magnitude smaller than reported in published measurements of fluid lift forces. A system to determine such lift forces has been developed and is described. Measurements of the mean force acting on particles on both rough and smooth surfaces are presented.The data recorded here for the mean fluid lift force on a sphere on a smooth surface are in good agreement with the relationship \[ F^{+} = (20.90\pm 1.57)(a^{+})^{2.31\pm 0.02}, \] where F+ is the non-dimensional force and a+ the non-dimensional particle radius scaled on fluid-boundary-layer parameters. It was observed that surface roughness can change the force by up to a factor of six.

scholarly journals The relationship of shortening and strength of eggshell to some egg quality indicators and egg production in hens of different initial laying lines*

2002 ◽  
Vol 45 (3) ◽  
pp. 287-296 ◽  
Author(s):  
L. Máchal ◽  
J. Simeonovová
Keyword(s):  
Rhode Island ◽  
Egg Production ◽  
Egg Quality ◽  
Mean Values ◽  
Time Period ◽  
The Mean ◽  
Positive Correlations ◽  
Shape Ratio ◽  
Relationship Of ◽  
The Relationship

Abstract. The mean values of shortening force at fracture of egg found out during the five-month observation period ranged between 0.17 and 0.19 mm in 231 hens of seven initial laying lines and strength of eggshell ranged from 29.05 N to 36.46 N. The mean values of shortening force at fracture decreased with age of hens from 0.18–0.22 mm at 28 wk of age to 0.12–0.15 mm at 46 wk of age. Similarly, strength of eggshell decreased from 31.35–37.68 N to 27.91–34.50 N in same time period. Index of shape, ratio of eggshell and albumen to total egg weight also decreased with increasing age of hens. The highest ratio of abnormal eggs was found in both Bar Plymouth Rock lines (BPR A and BPR B) – 7.5% and 8.3% resp. The lowest ratio was found in lines Rhode Island Red (RIR C) – 2.1% and Susex Light (SU) – 2.4 %. The ratio of cracked eggs ranged from 0.9 % to 3.9 %, the ratio of double-yolked eggs was 0.5%–3.2% and the ratio of eggs without shell was 0.4 %–1.5 %. The calculated coefficients of correlation between shortening of egg and index of shape were mainly positive with rp = 0.41 (P < 0.05) and rp = 0.49 (P < 0.01). The correlations between shortening of egg and total number of eggs were mainly negative with rp = −0. 34 (P < 0.05) and rp = −0. 46 (P < 0.01). Similar correlations existed also between shortening of egg and ratio of cracked eggs, i.e. rp = −0. 44 (P < 0.05) and rp = −0. 46 (P < 0.01). The correlations between shortening and total number of abnormal eggs were mainly negative rp = −0. 39 (P < 0.05) and rp = −0. 53 (P < 0.01). The relationships between strength of eggshell and shortening of egg are characterized by positive correlations – rp = 0. 40 (P < 0.05) and rp = 0.55, (P < 0.01). Positive correlations existed also between strength of eggshell and index of shape (from rp = 0. 37 (P < 0.05) to rp = 0.59 (P < 0.01)). Correlations between strength of eggshell and ratio of eggshell ranged from rp = 0.44 (P < 0.01) to rp = 0.74 (P < 0.01). Mainly negative correlations were found out between strength of eggshell and number of eggs rp = −0. 34 (P<0.05) and rp = −0. 44 (P < 0.01), similarly between the strength of eggshell and cracked eggs rp = −0. 40 (P < 0.05) and rp = −0. 52 (P < 0.01). Negative correlations existed between strength of eggshell and total number of abnormal eggs (rp = −0.45 to rp = −0.53 (P < 0.01)). This means that both eggshell shortening and strength may be used when selecting lines for egg quality.

scholarly journals Climatic control on the variability of flood distribution

2002 ◽  
Vol 6 (2) ◽  
pp. 229-238 ◽  
Author(s):  
V. Iacobellis ◽  
P. Claps ◽  
M. Fiorentino
Keyword(s):  
Coefficient Of Variation ◽  
Rainfall Intensity ◽  
Annual Maximum ◽  
Climatic Control ◽  
Flood Peaks ◽  
Areal Rainfall ◽  
Two Parameters ◽  
The Relationship ◽  
Basin Area ◽  
Good Agreement

Abstract. The variability of the second order moments of flood peaks with respect to geomorphoclimatic basin characteristics was investigated. In particular, the behaviour of the coefficient of variation (Cv) of the series of annual maximum floods was analysed with respect to its dependence on physically consistent quantities. The results achieved were in fairly good agreement with real world observed characteristics and interesting insights on the relationship between Cv and basin size were found. It appears that Cv is controlled mainly by the climate and by some water loss features. Many observations reported in the literature show a decrease of Cv with basin area A, usually ascribed to the limited spatial extent of extreme events, which leads to a decrease with area of the Cv of areal rainfall intensity. An increase of Cv with the area is also sometimes observed for small basins. Such different behaviours were accounted for by the concurrent effect on two parameters that affect the Cv (A) relationship, representative of the way rainfall losses and effective rainfall intensity scale with the basin area. Keywords: floods, climate, coefficient of variation, scaling.

scholarly journals On Respiratory Rate of Cherry Tomatoes under Subcritical Heights

2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
Fang Duan ◽  
Yu-fen Chen ◽  
Zhong-zheng Sun ◽  
Ming-qing Chen ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Respiratory Rate ◽  
Respiration Rate ◽  
Mean Value ◽  
The Mean ◽  
The Relationship ◽  
Cherry Tomatoes ◽  
Good Agreement

The influence of subcritical drop heights on respiratory rate was studied for cherry tomatoes. The cherry tomatoes were dropped, and the mean value of O2concentration was measured, and then the respiration rate was calculated. The results showed that the respiration rate of the cherry tomatoes increases remarkably with the dropping height. Finally, the relationship between the subcritical dropping heights and respiration rate was modeled and validated, showing good agreement.

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