Oscillatory Fouling in Condensers in Cooling Tower Systems

2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Wei Li
Keyword(s):  
Theoretical Analysis ◽  
Cooling Tower ◽  
Oscillatory Behavior ◽  
Water Velocity ◽  
Experimental Uncertainty ◽  
Physical Mechanisms ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship

Abstract Oscillatory fouling in condensers using cooling tower water was recognized in 1980s, but it had not yet been theoretically analyzed. Without careful theoretical analysis, it is easy to think that oscillatory fouling phenomenon is generated from experimental uncertainty. The new analysis is to split the fouling rate into a mean variable and a fluctuating variable. The mean variable exhibits an asymptotic behavior, and the fluctuating variable exhibits an oscillatory behavior. A theoretical analysis based on the relationship of continuity is used to present fouling oscillatory behavior along the space and time dimensions simultaneously to provide the intuitive understanding in physical mechanisms driving the phenomenon. A series of long-term cooling tower water fouling tests were conducted: fouling data collected in two copper helically ribbed tubes with the same internal and external diameters and different inside geometric parameters at the same water velocity in condenser in practical cooling tower conditions present oscillatory behavior. The frequencies of the fluctuation are the same for the two tested tube geometries. The spatial and the temporal oscillatory fouling behaviors presented in the experimental results are predicted by the theoretical analysis.

Multi-Center Calibration of the Second Reference Material for Thromboplastin, Rabbit, Plain, Coded CRM 149R

1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Reference Material ◽  
Standard Error ◽  
Standard Errors ◽  
Sensitivity Index ◽  
Long Term Stability ◽  
Significant Bias ◽  
The Mean ◽  
The Relationship ◽  
International Sensitivity Index

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.

scholarly journals Domain randomization-enhanced deep learning models for bird detection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xin Mao ◽  
Jun Kang Chow ◽  
Pin Siang Tan ◽  
Kuan-fu Liu ◽  
Jimmy Wu ◽  
...  
Keyword(s):  
Deep Learning ◽  
Continuous Monitoring ◽  
Bird Species ◽  
Training Data ◽  
Learning Models ◽  
Fine Grained ◽  
Bird Detection ◽  
Relationship Of ◽  
The Relationship

AbstractAutomatic bird detection in ornithological analyses is limited by the accuracy of existing models, due to the lack of training data and the difficulties in extracting the fine-grained features required to distinguish bird species. Here we apply the domain randomization strategy to enhance the accuracy of the deep learning models in bird detection. Trained with virtual birds of sufficient variations in different environments, the model tends to focus on the fine-grained features of birds and achieves higher accuracies. Based on the 100 terabytes of 2-month continuous monitoring data of egrets, our results cover the findings using conventional manual observations, e.g., vertical stratification of egrets according to body size, and also open up opportunities of long-term bird surveys requiring intensive monitoring that is impractical using conventional methods, e.g., the weather influences on egrets, and the relationship of the migration schedules between the great egrets and little egrets.

Intra-Task Reliability and Specificity of Individual Consistency

1970 ◽  
Vol 30 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Albert V. Carron
Keyword(s):  
Motor Response ◽  
Present Report ◽  
Motor Task ◽  
Response Component ◽  
Linear Movement ◽  
The Mean ◽  
Individual Consistency ◽  
Response Consistency ◽  
Relationship Of ◽  
The Relationship

The present report is based on reanalysis of data of Marisi (1969) in order to examine the relationship of consistency of motor response among the component responses of a single motor task. 120 high school Ss were tested on a special task, the rho. A single trial on this motor task can be logically separated into three component motor responses: reaction time, a short circular movement, and a short linear movement. The results indicated that consistency of motor response was moderately reliable within the response components but tended to be response-component specific. Further, both the reliability and specificity of motor-response consistency were independent of the size of the mean performance scores.

Technology and Employment in Developing Countries

1978 ◽  
Vol 16 (4) ◽  
pp. 549-564 ◽  
Author(s):  
J. W. Garmany
Keyword(s):  
Developing Countries ◽  
Optimum Combination ◽  
Current Consumption ◽  
The Creation ◽  
Relationship Of ◽  
The Relationship ◽  
Choice Of Technology

This article discusses some of the issues involved in the choice of technology in developing countries, especially those in Africa, and the relationship of this to employment and output. The problem is to find an optimum combination of productive resources that comes nearest to satisfying two objectives: the full and economically efficient utilisation of such resources, and the creation of as much surplus as possible over current consumption, thereby making possible new investment and long-term growth.

scholarly journals The Relationship between Reputation, Customer Satisfaction, Trust, and Loyalty

2014 ◽  
Vol 4 (3) ◽  
pp. 368 ◽  
Author(s):  
Roshana Gul
Keyword(s):  
Customer Satisfaction ◽  
Customer Loyalty ◽  
Significant Relationship ◽  
Positive Sign ◽  
Medical College ◽  
Independent Variable ◽  
Relationship Of ◽  
The Relationship ◽  
Self Administered Questionnaire

Though a lot of studies have been done to conclude customer loyalty as dependent variable but still there is a vast margin of researches to be conducted in future in different spheres of this construct. On the other hand the truth of the importance of customer loyalty as an enduring asset cannot be falsified. It is fundamental for organizations to build up long term and mutual beneficial associations with the customers. The purpose of this research paper is to show the inter relationship of reputation, customer satisfaction and trust on customer loyalty. According to the observations reputation is the major independent variable that has significant relationship with customer satisfaction, customer loyalty, and trust. Data for this research study was taken from the Islamia University, Quaid-e-Azam Medical College, and different banks located at various geographic locations of Bahawalpur region of Pakistan. Data was collected through self administered questionnaire and analyzed by using regression through SPSS. The results have been drawn from 150 users of NISHAT LINEN and it was found that there is positive and significant relationship among reputation, customer satisfaction, trust and customer loyalty. Hence the studies give the positive sign that with the increment of reputation, customer satisfaction and trust the customer loyalty enhances.  

Respiratory Periodicity and Electroencephalogram Arousals During Sleep in Older Adults

2007 ◽  
Vol 8 (4) ◽  
pp. 249-260 ◽  
Author(s):  
Barbara Waag Carlson ◽  
Virginia J. Neelon ◽  
John R. Carlson ◽  
Marilyn Hartman ◽  
Sunil Dogra
Keyword(s):  
Older Adults ◽  
Exploratory Study ◽  
High Variability ◽  
Arterial Oxygenation ◽  
Type B ◽  
Breathing Patterns ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship ◽  
Electroencephalogram Eeg

The aim of this exploratory study was to examine the relationship of electroencephalogram (EEG) arousals to breathing patterns and the relationship of both arousals and breathing patterns to arterial oxygenation during sleep in older adults. Five older adults were monitored using standard polysomnography. Records were divided into 5-min segments and breathing patterns identified based on the level of respiratory periodicity and the variability in the frequency of breathing cycles. Standard criteria were used to determine sleep states and occurrence of EEG arousals. High respiratory periodicity was seen in 23% of the segments, whereas 24% had low respiratory periodicity with minimal variability in the frequency of breathing (Type A low respiratory periodicity) and 53% had low respiratory periodicity with high variability in the frequency of breathing (Type B low respiratory periodicity). Nearly all (97%) segments with high respiratory periodicity had EEG arousals, whereas fewer segments (33%) with low respiratory periodicity had arousals, regardless of the stage of sleep. Desaturations occurred more often in segments with high respiratory periodicity, F (2,4) = 57.3, p < .001, but overall, the mean SaO2 of segments with high respiratory periodicity did not differ from levels seen in segments with low respiratory periodicity, F( 2,4) = 0.77, ns. Our findings suggest that high respiratory periodicity is a common feature of EEG arousals and, in older adults, may be important for maintaining oxygen levels during desaturations during sleep.

scholarly journals Astrometric and Photometric Variability in Quasars

2009 ◽  
Vol 5 (S267) ◽  
pp. 103-103
Author(s):  
A. H. Andrei ◽  
S. Bouquillon ◽  
J. L. Penna ◽  
F. Taris ◽  
S. Anton ◽  
...  
Keyword(s):  
Strong Support ◽  
Optical Emission ◽  
Optical Observations ◽  
Massive Black Hole ◽  
Full Account ◽  
Photometric Variability ◽  
Central Engine ◽  
Relationship Of ◽  
The Relationship

Quasars are the choicest objects to define a quasi-inertial reference frame. At the same time, they are active galactic nuclei powered by a massive black hole. As the astrometric precision of ground-based optical observations approaches the limit set by the forthcoming GAIA mission, astrometric stability can be investigated. Though the optical emission from the core region usually exceeds the other components by a factor of a hundred, the variability of those components must surely imply some measure of variability of the astrometric baricenter. Whether this is confirmed or not, it puts important constraints on the relationship of the quasar's central engine to the surrounding distribution of matter. To investigate the correlation between long-term optical variability and what is dubbed as the “random walk” of the astrometric center, a program is being pursued at the WFI/ESO 2.2m. The sample was selected from quasars known to undergo large-amplitude and long-term optical variations (Smith et al. 1993; Teerikorpi 2000). The observations are typically made every two months. The treatment is differential, comparing the quasar position and brightness against a sample of selected stars for which the average relative distances and magnitudes remain constant. The provisional results for four objects bring strong support to the hypothesis of a relationship between astrometric and photometric variability. A full account is provided by Andrei et al. (2009).

scholarly journals Relationship of altitude mountain sickness and smoking: a Catalan traveller’s cohort study

BMJ Open ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. e017058 ◽  
Author(s):  
Alba Sánchez-Mascuñano ◽  
Cristina Masuet-Aumatell ◽  
Sergio Morchón-Ramos ◽  
Josep M Ramon
Keyword(s):  
Smoking Status ◽  
Medical Advice ◽  
Health Clinic ◽  
Travel Health ◽  
Systemic Corticosteroids ◽  
The Mean ◽  
Mountain Sickness ◽  
Relationship Of ◽  
The Relationship ◽  
Chronic Use

ObjectivesThe aim of this study is to analyse the relationship between smoking andaltitude mountain sicknessin a cohort of travellers to 2500 metres above sea level (masl) or higher.SettingTravel Health Clinic at the Hospital Universitari de Bellvitge, in Barcelona, Spain.ParticipantsA total of 302 adults seeking medical advice at the travel clinic, between July 2012 and August 2014, before travelling to 2500 masl or above, who agreed to participate in the study and to be contacted after the trip were included. Individuals who met the following criteria were excluded: younger than 18 years old, taking carbonic anhydrase inhibitors for chronic use, undergoing treatment with systemic corticosteroids and taking any medication that might prevent or treat altitude mountain sickness (AMS) prior to or during the trip. The majority of participants were women (n=156, 51.7%). The mean age was 37.7 years (SD 12.3). The studied cohort included 74 smokers (24.5%), 158 (52.3%) non-smokers and 70 (23.2%) ex-smokers. No statistical differences were observed between different sociodemographic characteristics, constitutional symptoms or drug use and smoking status.OutcomesThe main outcome was the development of AMS, which was defined according to the Lake Louise AMS criteria.ResultsAMS, according to the Lake Louise score, was significantly lower in smokers; the value was 14.9%, 95% CI (6.8 to 23.0%) in smokers and 29.4%, 95% CI (23.5 to 35.3%) in non-smokers with an adjusted OR of 0.54, 95% CI (0.31 to 0.97) independent of gender, age and maximum altitude reached.ConclusionsThese results suggest that smoking could reduce the risk of AMS in non-acclimated individuals. Further studies should be performed in larger cohorts of travellers to confirm these results. Despite the results, smoking must be strongly discouraged because it greatly increases the risk of cardiorespiratory diseases, cancer and other diseases.

scholarly journals Frequency of non-motor symptoms in Peruvian patients with Parkinson's disease

2013 ◽  
Vol 71 (4) ◽  
pp. 216-219 ◽  
Author(s):  
Carlos Cosentino ◽  
Yesenia Nuñez ◽  
Luis Torres
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Progressive Increase ◽  
Motor Symptoms ◽  
Number Of Patients ◽  
Progression Of Disease ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship ◽  
Non Motor Symptoms

Introduction: Non-motor symptoms in Parkinson's disease are often not well recognized in clinical practice. Non-motor symptoms questionnaire (NMSQuest) is a simple instrument that allows patients or caregivers to report non-motor symptoms in a practical manner. Objective: We attempted to determine the prevalence of non-motor symptoms in three hundred Parkinson's disease outpatients. Results: The mean total non-motor symptoms was 12.41, ranging from 0 to 27 of a maximum of 30. At least one was present in 99.3% of patients. A progressive increase in mean total score was observed across each 5-year interval. Depression domain scored the most “positive” answers while urinary and anxiety /memory were secondly and thirdly most prevalent respectively. Conclusion: The large number of patients included in this study allowed evaluation of the occurrence of non-motor symptoms in early and advanced disease in addition to the relationship of these kinds of symptoms with progression of disease.

scholarly journals Career Satisfaction Based on Trust and Proactive Personality

2020 ◽  
Vol 9 (1) ◽  
pp. 35-45
Author(s):  
Iwan Sunardi ◽  
Vini Wiratno Putri
Keyword(s):  
Career Satisfaction ◽  
Analytical Data ◽  
Sampling Technique ◽  
Test Methods ◽  
Validity And Reliability ◽  
Career Needs ◽  
Relationship Of ◽  
The Relationship ◽  
The City

The purpose of this study was to examine the effect of the trust of co-workers and proactive personalities on career satisfaction by exchanging leader-members as mediation on employees of bus assembly companies in the city of Semarang. Career satisfaction is the phase in which employees’ long-term career needs are aligned with what they get while working. Employees will always look for opportunities and trust in the organization and people who will help them in achieving career satisfaction. The sampling method uses a purposive sampling technique in the category of staff and foreman employees who have worked for more than five years with a sample of 160 employees. The analytical data in this study uses descriptive statistical test methods, instinctual tests include validity and reliability, and hypothesis testing. The tool used to test in this study uses SmartPLS 3.0. The results of this study, colleague trust cannot directly influence career satisfaction. However, it can be mediated by the exchange of leader members and produce significant influence. For further researchers, they can re-examine the relationship of coworkers’ trust with career satisfaction. And can expand the object of research or respondents under study.

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