scholarly journals In day 150 of COVID-19 disease, forecasting the number of cases and deaths in Turkey

2020 ◽  
Vol 7 (6) ◽  
pp. 535-545
Author(s):  
Yüksel Akay Ünvan ◽  
Oguzhan Demirel
Keyword(s):  
Test Results ◽  
Arima Models ◽  
Rate Of Spread ◽  
Augmented Dickey Fuller ◽  
First Occurrence ◽  
Biological Development ◽  
Adf Test ◽  
The Relationship ◽  
Expected Increase ◽  
Distribution Assumption

Objective:  This study aims to forecast the number of deaths and cases in Turkey 150 days after (6 August 2020) the first occurrence of COVID-19 in Turkey. The data used is from 10 March 2020 (the first day has seen of COVID-19 in Turkey) to 15 June 2020 and includes people of all ages from all provinces of Turkey. Material and Method: The relationship between cases, deaths, patients in intensive care units, intubated patients, and recovered patients, which are observations of COVID-19, was examined with a correlation matrix. Afterward, the ARIMA (0,2,4) model to forecast the number of COVID-19 cases in Turkey and the ARIMA(0,3,1) model to forecast the number of COVID-19 deaths in Turkey were established. Result: COVID-19 cases were forecasted that there may be 266.692 cases in Turkey on 6 August in the 1st model. Subsequently, a similar forecast has been made on COVID-19 deaths in Turkey on 6 August in the 2nd model. COVID-19 deaths were forecasted that there may be 5718. The p-values of these parameters of models were observed statistically significant (p<0.05). Later, the stationarity of ARIMA models related to these estimates was examined. According to the Augmented Dickey-Fuller (ADF) test results, ARIMA models were stationary and statistically convenient to use (p<0.05). Finally, the Jarque-Bera (JB) test examining the normal distribution assumption was applied and the models were found to be normally distributed. Conclusions: Consequently, there is an increase in both predicted cases and predicted deaths by the 150th day of COVID-19. These estimates show that the number of cases and deaths will not decrease to zero level until August 6. Factors such as the biological development of the COVID-19 virus, the rate of spread of COVID-19 disease, or the presence of COVID-19 therapy may not cause any increase in these observations. On the contrary, more than expected increase may occur in observed cases.

scholarly journals The Analysis of Income Inequality and Economic Growth Relationship: Evidence from Pakistan’s Data

2016 ◽  
Vol I (I) ◽  
pp. 24-35
Author(s):  
Saleem Khan ◽  
Salman Azad Khan ◽  
Muhammad Tariq
Keyword(s):  
Economic Growth ◽  
Income Inequality ◽  
Test Results ◽  
Coefficient Estimates ◽  
Lagged Dependent Variable ◽  
Simple Regression Analysis ◽  
Adf Test ◽  
The Relationship ◽  
Distribution Of Income ◽  
Simple Regression

This research gives a brief overview of Pakistan’s economic growth and income inequality, and empirically assesses the relationship between these two variables of the country over the period of 1990 – 2015. In the empirical part, our study employs the augmented ADF test and simple regression analysis. ADF test results depict that both variables of the model are stationary at the level and exhibit no unit root at the level. Further, in regression results, the coefficient estimates are significant and reveal an inverted U linkage between economic growth of the country and distribution of income. The income level of the country alone explains a significant part of the income inequality. Instead, the lagged dependent variable coefficient is significant and partly explains variation in inequality.

scholarly journals Comparison of the Performance of the SANN, SARIMA and ARIMA Models for Forecasting Quarterly GDP of Nigeria

2021 ◽  
pp. 1-20
Author(s):  
Chukwudike C. Nwokike ◽  
Emmanuel W. Okereke
Keyword(s):  
Mean Squared Error ◽  
Predictive Performance ◽  
Arima Models ◽  
Data Set ◽  
Variance Stabilization ◽  
Augmented Dickey Fuller ◽  
Chi Squared ◽  
Competing Models ◽  
Hidden Layer ◽  
Adf Test

This research aimed at modelling and forecasting the quarterly GDP of Nigeria using the Seasonal Artificial Neural Network (SANN), SARIMA and Box-Jenkins models as well as comparing their predictive performance. The three models mentioned earlier were successfully fitted to the data set. Tentative architecture for the SANN was suggested by varying the number of neurons in the hidden layer while that of the input and output layer remained constant at 4. It was observed that the best architecture was when the hidden layer had 10 neurons and thus SANN (4-10-4) was chosen as the best. In fitting the ARIMA/SARIMA models, the Augmented Dickey Fuller (ADF) test was used to check for stationarity. Variance stabilization and Stationarity were achieved after logarithm transformation and first regular differencing. The ARIMA/SARIMA model with lowest AIC, BIC and HQIC values was chosen as the best amongst the competing models and fitted to the data. The adequacy of the fitted models was confirmed observing the correlogram of the residuals and the Ljung-Box Chi-Squared test result. The SANN model performed better than the SARIMA and ARIMA models as it had a Mean Squared Error value of 0.004 while SARIMA and ARIMA had mean squared errors of 0.527 and 0.705 respectively. It was concluded that the SANN which is a non-linear model be used in modelling the quarterly GDP of Nigeria. Hybrid models which combine the strength of individual models are recommended for further research.

Problematic Internet Use digunakan Ketika Kesepian pada Remaja

2020 ◽  
Vol 14 (1) ◽  
pp. 45-60
Author(s):  
Yashinta Yashinta ◽  
Dwi Hurriyati
Keyword(s):  
Internet Use ◽  
Hypothesis Test ◽  
Problematic Internet Use ◽  
Coefficient Of Determination ◽  
Test Results ◽  
Research Subjects ◽  
Significance Level ◽  
Relationship Of ◽  
The Relationship ◽  
Effective Contribution

This study aims to determine the relationship of loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city. Research subjects numbered 220 people using random sampling methods. Data was collected using a 60 item problematic internet use scale and a 60 item loneliness. Realibility is generated on scale of problematic internet use of 0,955 and loneliness of 0,946.Hypothesis testing uses product moment correlation analysis techniques. Hypothesis test results showed a positive relationshif between loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city r= 0,684 with a significance level of 0,000 (p<0,01). Loneliness in this study made an effective contribution of 46,8% to problematic internet use which can be seen from the coefficient of determination (r²) that is equel to 0,468.

Sunlight exposure: the effects on the performance of paragliding fabric

2018 ◽  
Vol 69 (05) ◽  
pp. 381-389
Author(s):  
MENGÜÇ GAMZE SÜPÜREN ◽  
TEMEL EMRAH ◽  
BOZDOĞAN FARUK
Keyword(s):  
Mechanical Properties ◽  
Aging Process ◽  
Air Permeability ◽  
Sunlight Exposure ◽  
Test Results ◽  
Coating Materials ◽  
Strength Tests ◽  
Before And After ◽  
The Relationship ◽  
Dark Blue

This study was designed to explore the relationship between sunlight exposure and the mechanical properties of paragliding fabrics which have different colors, densities, yarn counts, and coating materials. This study exposed 5 different colors of paragliding fabrics (red, turquoise, dark blue, orange, and white) to intense sunlight for 150 hours during the summer from 9:00 a.m. to 3:00 p.m. for 5 days a week for 5 weeks. Before and after the UV radiation aging process, the air permeability, tensile strength, tear strength, and bursting strength tests were performed. Test results were also evaluated using statistical methods. According to the results, the fading of the turquoise fabric was found to be the highest among the studied fabrics. It was determined that there is a significant decrease in the mechanical properties of the fabrics after sunlight exposure. After aging, the fabrics become considerably weaker in the case of mechanical properties due to the degradation in both the dyestuff and macromolecular structure of the fiber

Adolescent smoking behavior and communication with parents: Depression as a mediator and gender as a moderator

2019 ◽  
Vol 47 (10) ◽  
pp. 1-9 ◽  
Author(s):  
Xieping Chen ◽  
Qian Xie ◽  
Yuting Yang
Keyword(s):  
Smoking Behavior ◽  
Depression Scale ◽  
Epidemiological Studies ◽  
Adolescent Smoking ◽  
Junior High Schools ◽  
Test Results ◽  
Negative Effect ◽  
And Gender ◽  
The Relationship ◽  
Communication Scale

Parent–adolescent communication is assumed to be an important factor affecting adolescent smoking behavior. However, the inner mechanism accounting for this association has still not been clarified in research. Our purpose in this study was to examine the relationships between parent–adolescent communication, adolescent smoking behavior, and depression, as well as gender differences in the relationship between depression and adolescent smoking behavior. Participants were 1,134 students at 6 junior high schools in China who completed the Parent-Adolescent Communication Scale, the Epidemiological Studies Depression Scale, and the Smoking Behavior Test. Results showed that parent-adolescent communication had a significant negative effect on adolescent smoking behavior and depression partially mediated the relationship between parent–adolescent communication and adolescent smoking behavior. In addition, gender moderated the relationship between depression and adolescent smoking behavior. Overall, these findings may help to promote better understanding of the relationship between parent–adolescent communication and adolescent smoking behavior.

A Study on Estimation of Internal Pressure Creep Life Using Small Punch Creep (SPC) Tests for Boiler Pipes

2009 ◽  
Author(s):  
Toshimi Kobayashi ◽  
Toru Izaki ◽  
Junichi Kusumoto ◽  
Akihiro Kanaya
Keyword(s):  
Internal Pressure ◽  
Residual Life ◽  
Test Results ◽  
Creep Life ◽  
Creep Tests ◽  
Good Correspondence ◽  
Small Punch ◽  
Uniaxial Creep ◽  
Wide Range ◽  
The Relationship

The small punch creep (SPC) test is possible to predict residual creep life at a high accuracy. But, the results of SPC tests cannot be compared with uniaxial creep or internal pressure creep results directly. In this report, the relationship between SPC test results and uniaxial creep test results in ASME A335 P11 (1.25Cr-0.5Mo Steel) was studied. The obtained relationship between SPC load and equivalent uniaxial creep stress formed a simple linear equation under the wide range of test temperature and test period. Then, the SPC results can be compared with uniaxial results by converting SPC loads to the equivalent uniaxial creep stresses. The relationship between SPC test results and internal pressure creep tests results was also studied. The internal creep life of as-received P11 pipe was almost same as SPC result when the hoop stress was converted to the SPC load. The creep lives of internal pressure creep influenced materials also showed good correspondence with SPC results. Therefore SPC can estimate the residual life of internal pressure creep influenced materials.

Size Effect on Mechanical Properties of LVL

2014 ◽  
Vol 887-888 ◽  
pp. 824-829
Author(s):  
Qing Fang Lv ◽  
Ji Hong Qin ◽  
Ran Zhu
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Size Effect ◽  
Tensile Test ◽  
Compression Test ◽  
Test Results ◽  
Laminated Veneer Lumber ◽  
Object Of Study ◽  
The Relationship

Laminated veneer lumber is taken as an object of study, and use LVL specimens of different sizes for compression test and tensile test. The goal of the experiment is to investigate the size effect on compressive strength and tensile strength as well as the influence of the secondary glued laminated face, which appears in the secondary molding processes. The results show that both compressive strength and tensile strength have the size effect apparently and the existence of the secondary glued laminated face lower the compressive strength of LVL specimens. Afterwards, the relationship between compressive strength and volume along with tensile strength and area are obtained by the test results.

scholarly journals Compressibility behaviour of remoulded, fine-grained soils and correlation with index properties

2000 ◽  
Vol 37 (3) ◽  
pp. 712-722 ◽  
Author(s):  
A Sridharan ◽  
H B Nagaraj
Keyword(s):  
Liquid Limit ◽  
Plasticity Index ◽  
Engineering Properties ◽  
Test Results ◽  
Index Properties ◽  
Initial Water ◽  
Fine Grained ◽  
Wide Range ◽  
The Relationship ◽  
Water Contents

Correlating engineering properties with index properties has assumed greater significance in the recent past in the field of geotechnical engineering. Although attempts have been made in the past to correlate compressibility with various index properties individually, all the properties affecting compressibility behaviour have not been considered together in any single study to examine which index property of the soil correlates best with compressibility behaviour, especially within a set of test results. In the present study, 10 soils covering a sufficiently wide range of liquid limit, plastic limit, and shrinkage limit were selected and conventional consolidation tests were carried out starting with their initial water contents almost equal to their respective liquid limits. The compressibility behaviour is vastly different for pairs of soils having nearly the same liquid limit, but different plasticity characteristics. The relationship between void ratio and consolidation pressure is more closely related to the shrinkage index (shrinkage index = liquid limit - shrinkage limit) than to the plasticity index. Wide variations are seen with the liquid limit. For the soils investigated, the compression index relates better with the shrinkage index than with the plasticity index or liquid limit.Key words: Atterberg limits, classification, clays, compressibility, laboratory tests.

Mathematics Grade as Correlate to Performance in the National Achievement Test

2020 ◽  
Vol 8 (1) ◽  
pp. 31-41
Author(s):  
Daryl T. Paredes ◽  
Ronalyn G. Albopera ◽  
Gladys T. Balog ◽  
Vincent A. Buladas ◽  
Mary Grace D. Hoyle ◽  
...  
Keyword(s):  
Academic Performance ◽  
Significant Degree ◽  
Achievement Test ◽  
Department Of Education ◽  
Test Results ◽  
Achievement Level ◽  
School Year ◽  
Documentary Analysis ◽  
Student’S Performance ◽  
The Relationship

Tests in schools can be informative. However, the Department of Education administered a set of examinations like the National Achievement Test which is designed to determine the learner's achievement level, strengths, and weaknesses in five curricular subject areas at the end of the school year. The study intended to look into the relationship between academic performance in Mathematics and NAT results. There has been a purposive universal sampling design. It is purposive because the research is only studying the academic performance in Mathematics, and universal because the subjects of the study are all the grade six pupils of Victoriano D. Tirol Advanced Learning Center for four consecutive school years. Documentary analysis was used as to the data of existing records on the academic performance and National Achievement Test results in Mathematics. The association between academic achievement and NAT outcomes in Mathematics was investigated using correlation analysis and one-way analysis of variance (ANOVA). The analyses revealed that there is a significant correlation between the pupil's academic performance and NAT results. Also, there is a significant degree of variance in the student's performance as to National Achievement Test Results in four consecutive school years.

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