Test Analysis Methods Research Articles

Multiple rounds using mixed chaotic keys method for secure message cryptography

Protecting secret messages from being hacked is a vital problem. This research paper will present a simple and flexible data cryptography method. The method can encrypt-decrypt messages of any length. Also, it can be easily used to encrypt-decrypt gray and color images. The proposed method will use a private key, which contains the needed information to generate chaotic keys; these keys will be used to obtain indices keys, which will be used as a lockup table in the encryption and decryption phases. The generated key will be very sensitive to the P.K. contents. The P.K. used in the proposed method will have a complex structure, providing a huge key space that can resist attacks. The proposed method will be implemented using various messages, the obtained results will be analyzed, and several test analysis methods will be used to prove the achievements of the proposed method. The quality analysis will use the calculated values of MSE, PSNR, CC, and NSCR to prove the quality of the proposed method in both the encryption and decryption phases. A sensitivity analysis will be performed to show how the encryption and decryption phase is sensitive to the selected P.K.; any changes in the P.K. during the decryption phase will be considered a hacking attempt by producing a damaged decrypted message. A speed analysis will be provided to prove that the proposed method is efficient, and the obtained results will be compared with other methods' results to show the speedup provided by the proposed method.

Research on application technology of lithium battery assessment technology in energy storage system

Due to the complexity of the state change mechanism of lithium batteries, there are problems such as difficulties in aging characterization. Establishing a state assessment model for lithium batteries can reduce its safety risk in energy storage power station applications. Therefore, this paper proposes a method for establishing a lithium battery model including aging resistance under the combination of digital and analog, and uses the time–frequency domain test analysis method to establish the aging impedance expression to realize the parameterization of the aging process and state estimation of lithium batteries. A battery model that can characterize the battery aging process is established by combining digital and simulation methods, and the equivalent representation of the lithium battery aging process is realized. Finally, a simulation example is designed to verify its effectiveness, which provides important reference value for the practical engineering application of lithium battery energy storage system.

DETERMINANTS OF FAST FOOD CONSUMPTION BEHAVIOR IN ADOLESCENTS IN THE CITY OF JAKARTA

Fast food is high in calories and fat. Consuming fast food excessively can cause various health problems, including obesity. This study aims to determine the factors related to the behavior of fast food consumption in adolescents at SMA Negeri 30 Jakarta in 2022. The research design was quantitative with a cross-sectional approach. Data collection in this study was carried out in April - May 2022 with a population of 884. A total of 200 respondents as samples were collected and processed using the Quota Sampling sampling technique. This research employs univariate, bivariate, and Chi-Square test analysis methods. The results of the univariate analysis of most categories showed that adolescents often consumed fast food (51%), female gender (59.5%), had good knowledge (65%), had a positive attitude (59%), had a positive body image (56%), has high pocket money (66.5%), is not affected by social media (68.5%), not affected by peers (78%) and unaffected by promotion (65%). The bivariate analysis showed a relationship between knowledge (p-value= 0.000; PR= 2.566; 95% CI= 1.661-3.963), body image (p-value= 0.035; PR= 1.381; 95% CI= 1.042-1.830) , pocket money (p-value= 0.046; PR= 1.369; 95% CI= 1.039-1.804), and the influence of promotion (p-value = 0.009; PR= 1.572; 95% CI= 1.109-2.229) on fast food consumption behavior.

Influence of the experience of the project manager and the foreman on project management’s success in the context of LPS implementation

Production planning is a key element for success in building project management. Last Planner System (LPS) has emerged as an alternative proactive management method through the commitment of the different stakeholders involved in the project; however, further research is required to determine the factors that can affect the success of LPS implementation. This research aims to analyze how the implementation of LPS and the construction management experience of the project manager and the construction site foreman individually influence project management's success, getting minimum time and cost deviations. In this work, newly built single-family house projects were analyzed. Quantitative and qualitative analyses, based on the Mann–Whitney U test and qualitative comparative analysis method, respectively, were performed to constrain both the individual and combined effects of LPS, the project foreman, and the project manager in terms of cost and time deviation as measures of project management success. The results highlight that LPS implementation is significant in terms of time deviation and combined LPS implementation and the foreman's experience in construction management are sufficient to maintain time deviations below 10%. However, among the studied variables, only the foreman’s experience is a required condition to maintain cost deviations under 10%. Overall, this study may help construction organizations to improve their managerial practices at construction sites.

Development and validation of a stability-indicating RP-HPLC method for estimation of Lefamulin in pure and pharmaceutical drug products

BackgroundCommonly occurring serious lung parenchymal infection is community-acquired bacterial pneumonia (CABP). Lefamulin acetate drug products are useful for the treatment of community-acquired bacterial pneumonia (CABP). The main objective of the study was the development and validation of a quick reverse-phase high performance liquid chromatographic analytical testing method for Lefamulin in pure and pharmaceutical dosage forms. The C18 column was the stationary phase for reverse-phase high performance liquid chromatographic separation, and the mobile phase consisted of 0.05 M phosphate buffer with a pH adjustment of 2.5 mixed with an equal volume of acetonitrile. A flow rate of 1.0 mL/min, a column temperature of 30 °C, an injection volume of 10 µL, and a detection wavelength of 210 nm were used as optimum conditions.ResultsThe developed method reported that Lefamulin peak’s retention time was 3.1 min, the average theoretical plate count 5000, and the average peak asymmetry 1.12. In both pure and pharmaceutical dosage forms, the method was found to be accurate, precise, specific, linear calibration curve, and robust. Quantitative assay results from laboratory-made formulations showed similarity to existing commercial products of Lefamulin. Lefamulin is stable in acidic and photolytic environmental circumstances, while it degraded in oxidative, basic, and thermal humidity environment, according to the results of stress studies.ConclusionsThe developed analytical method is fast, economic and stability indicating. It is useful for routine pharmaceutical analysis where the Lefamulin is synthesized in pure form, pharmaceutical tablet formulation, and parenteral dosage form, for their quality and safety.

Relationship between Learning Patterns Through Online Media and Stress During the COVID-19 Pandemic in Middle School Students

The purpose of this research is to find out whether there is a relationship between learning patterns through online media and stress during the Covid-19 pandemic for students at SMP Negeri 03 Gunung Tabur in Berau Regency. This study used a design with a cross-sectional design approach. The sample in this study was carried out by means of a total sample of 230 students at SMP Negeri 3 Gunug Tabur. The relationship between the independent variables and also the dependent variable uses the Chi Square test analysis method. The results of the analysis using the chi square test obtained a p value = 0.006 (p value <0.05) with an OR of 2.431. There is a relationship between learning patterns through online media and stress during the Covid-19 pandemic for students at SMP Negeri 03 Gunung Tabur in Berau Regency.

OKUL ÖNCESİ ÖĞRETMENLERİNİN TEKNOLOJİK PEDAGOJİK ALAN BİLGİSİ ÖZGÜVENİ İLE TEKNOLOJİYE YÖNELİK TUTUMU ARASINDAKİ İLİŞKİNİN İNCELENMESİ

The purpose of this study is to examine the relationship between preschool teachers' technological pedagogical content knowledge (TPACK) confidence and their attitude towards technology. In addition, it was aimed to examine whether preschool teachers' technological pedagogical content knowledge and its sub-dimensions predict teachers' attitudes towards technology. The study group consists of 200 preschool teachers who teach 36-72-month-old preschool children in the 2020-2021 academic year. This study is a quantitative study designed in the single and relational screening model, one of the general screening models. The data were collected using the "Technological Pedagogical Content Knowledge Self-Confidence Scale (TPACKACKS)", "Attitude Towards Technology Scale" and "Personal Information Form". The data obtained were analyzed with SPSS 26.0 and JASP 0.16 programs and normality test, Pearson Correlation test and multiple linear regression analysis methods were used. As a result of the study, when the relationship between preschool teachers' attitudes towards technology and technological pedagogical content knowledge and sub-factors of it was examined, a significant positive relationship was found. When the other findings obtained from the research were examined, it was concluded that the relationship between preschool teachers' attitude towards technology scores and technological content knowledge sub-dimension scores was relatively low compared to other sub-dimensions.

Influences of cathode potential and carbon source on parabromoaniline degradation in microbial electrolysis cell

AbstractA microbial electrolysis cell was established to explore the degradation characteristics of characteristic pollutants in wastewater for parabromoaniline (P‐BrA). Their effects on P‐BrA reduction and degradation were investigated through factors such as impressed voltage and cosubstrate type. The P‐BrA residue and degradation in wastewater were analysed quantitatively through analytical testing methods, such as ultraviolet–visible, cyclic voltammetry, high‐performance liquid chromatograph, and scanning electron microscopy. The results showed that under the cathode potential of 0.5 V, electrons and electroactive microorganisms generate coupling action to accelerate the degradation of P‐BrA, reaching 94.94%. Moreover, the addition of carbon source organisms, such as glucose and sodium acetate, can facilitate the degradation of P‐BrA in the cathode chamber on the precondition that the electroactive anaerobic microbial C/N ratio was satisfied, both reaching over 90%. In addition, the microbial community diversity and richness of bioelectrochemistry system were enhanced after bioaugmentation. The increase in the Anacrolincalcs, Betaproteobacteriales, and Micrococcales also played an important role in the granulation of bioelectrochemistry system and the removal of characteristic pollutants.

Impact of the COVID-19 lockdown on typical ambient air pollutants: Cyclical response to anthropogenic emission reduction

Preliminary studies have confirmed that ambient air pollutant concentrations are significantly influenced by the COVID-19 lockdown measures, but little attention focus on the long term impacts of human countermeasures in cities all over the world during the period. Still, fewer have addressed their other essential properties, especially the cyclical response to concentration reduction. This paper aims to fill the gaps with combined methods of abrupt change test and wavelet analysis, research areas were made of five cities, Wuhan, Changchun, Shanghai, Shenzhen and Chengdu, in China. Abrupt changes in contaminant concentrations commonly occurred in the year prior to the outbreak. The lockdown has almost no effect on the short cycle below 30 d (days) for both pollutants, and a negligible impact on the cycle above 30 d. PM2.5 (fine particulate matter) has a stable short-cycle nature, which is greatly influenced by anthropogenic emissions. The analysis revealed that the sensitivity of PM2.5 to climate is increased along with the concentrations of PM2.5 were decreasing by the times when above the threshold (30–50 μg m−3), and which could lead to PM2.5 advancement relative to the ozone phase over a period of 60 d after the epidemic. These results suggest that the epidemic may have had an impact earlier than when it was known. And significant reductions in anthropogenic emissions have little impact on the cyclic nature of pollutants, but may alter the inter-pollutant phase differences during the study period.

Analysis of the Influence of Investment in Education and Health on Economic Growth in Malaysia

This study aims to determine the effect of education as seen from the mean year of schooling and literacy rate, health as seen from life expectancy and infant mortality rate on economic growth in Malaysia. This study uses the panel regression analysis method to see the effect of the independent variables on the dependent variable as seen from data in 2016 to 2020 in Malaysia. By using the Classic Assumption Test and Multiple Linear Regression Analysis methods to see whether the independent variables can affect the dependent variable in Malaysia. The results of this study indicate that mean year of schooling, literacy rate, life expectancy and infant mortality rate have no significant effect on economic growth in Malaysia. From the research results, it is suggested to the government to be able to improve the quality of education and health in the community by providing facilities evenly throughout the country. The need to raise awareness that the importance of education and health as human capital investment. In addition, there is a need for good education and health planning in an effort to improve the quality of human resources.

Stronger than Ever: Multifilament Fiberglass Posts Boost Maxillary Premolar Fracture Resistance.

This paper investigates the influence of cavity configuration and post-endodontic restoration on the fracture resistance, failure mode and stress distribution of premolars by using a method of fracture failure test and finite elements analysis (FEA) coupled to Weibull analysis (WA). One hundred premolars were divided into one control group (Gcontr) (n = 10) and three experimental groups, according to the post-endodontic restoration (n = 30), G1, restored using composite, G2, restored using single fiber post and G3, restored using multifilament fiberglass posts (m-FGP) without post-space preparation. Each experimental group was divided into three subgroups according to the type of coronal cavity configuration (n = 10): G1O, G2O, and G3O with occlusal (O) cavity configuration; G1MO, G2MO, and G3MO with mesio-occlusal (MO); and G1MOD, G2MOD, and G3MOD with mesio-occluso-distal (MOD). After thermomechanical aging, all the specimens were tested under compression load, and failure mode was determined. FEA and WA supplemented destructive tests. Data were statistically analyzed. Irrespective of residual tooth substance, G1 and G2 exhibited lower fracture resistance than Gcontr (p < 0.05), whereas G3 showed no difference compared to Gcontr (p > 0.05). Regarding the type of restoration, no difference was highlighted between G1O and G2O, G1MO and G2MO, or G1MOD and G2MOD (p > 0.05), whereas G3O, G3MO, and G3MOD exhibit higher fracture resistance (p < 0.05) than G1O and G2O, G1MO and G2MO, and G1MOD and G2MOD, respectively. Regarding cavity configuration: in G1 and G2, G1O and G2O exhibited higher fracture resistance than G1MOD and G2MOD, respectively (p < 0.05). In G3, there was no difference among G3O, G3MO and G3MOD (p > 0.05). No difference was found among the different groups and subgroups regarding the failure mode. After aging, premolars restored with multifilament fiberglass posts demonstrated fracture resistance values comparable to those of an intact tooth, irrespective of the different type of cavity configuration.

Rainfall and Streamflow Trends in the Upper &lt;em&gt;Maduru Oya&lt;/em&gt; Sub-watershed in Sri Lanka: A Comparative Study Using Different Statistical Methods

Analysis of historical data on rainfall and streamflow provides useful information for water resources management in a river basin. The objective of this study was to assess the variations and trend analysis of rainfall and streamflow data in the upper Maduru Oya sub watershed in Sri Lanka during a 30 year period (1989 October to 2019 September) using daily rainfall data from two gauging locations (Padiyathalawa and Bibile) and daily average streamflow data from one gauging location (Padiyathalawa). Descriptive statistics were used to assess the variations. The Mann Kendal Trend Test (MK test) and Innovative Trend Analysis method (ITA) were used to analyze the trend, and Sen’s Slope Estimator was used to assess the magnitude of the trend. Based on the MK test, most of the rainfall trends obtained are in an increasing direction, and streamflow trends are in a decreasing direction. Rainfall trends found in Padiyathalawa are not statistically significant. Annual, First Inter Monsoon, March, and May time scales of rainfall showed significant upward trends at Bibile (p&lt;0.1) while streamflow in January, April, and September showed significant negative trends (p&lt;0.1) at Padiyathalawa. The results displayed by all three tests were in very good agreement for rainfall. ITA results showed similar trend types of 77%, 95% and 41% at Padiyathalawa and Bibile rainfall and streamflow, respectively. A significant positive (ρ&lt;0.01) strong and lower correlation between the trend value of the ITA and the Z value of the MK test were found for rainfall and streamflow, respectively. Changes in rainfall are not sufficient to explain the observed trends in streamflow. Therefore, future research should be directed at the causal aspects of streamflow change in this watershed.

Development of high performance granite fine fly dust particle reinforced epoxy composites: structure, thermal, mechanical, surface and high voltage breakdown strength properties

The granite waste generated from the granite cutting and polishing industries contributes to lot of environmental contamination and health hazards. In the present work, an attempt has been made to assess the method to minimise environmental problems associated with granite dust pollution to the possible extent by converting the granite dust waste into value added high voltage electrical insulator products. Two types of epoxy matrices comprising bisphenol-A diglycidyl ether-phenalkamine (ER-1) and bisphenol-A diglycidyl ether-methyl hexahydrophthalic anhydride (ER-2) separately reinforced with varying weight percentages of (20, 40, 60, 80 and 100 wt%) of granite dust. The matrices and composites obtained were characterized for their structural, morphology, hydrophobic properties, thermal stability, mechanical strength, thermal conductivity, thermal resistivity, electrical resistivity, breakdown voltage and dielectric strength behaviour using appropriate analytical testing methods. Data resulted from different studies, it was inferred that the composites prepared using ER-2 possess better properties than those of ER-1. The composites with 100 wt% of cutting waste granite fly dust reinforced ER-2 possesses the higher values of electrical surface resistivity (5.22 × 1012 Ω), and electrical volume resistivity (5.60 × 1013 Ω) than those of neat ER-2 matrix (surface resistivity 4.82 × 109 Ω and volume resistivity 2.48 × 1013 Ω). The breakdown voltage and dielectric strength of ER-2 matrix were increased from 28 ±1 kV and 14 ± 0.5 kV/mm to 34 ±1 kV and 17 ± 0.5 kV/mm respectively, when reinforced with 100 wt % granite dust. The value of breakdown voltage was increased by 22% for 100 wt% granite dust reinforced composites when compared to that of neat epoxy matrix.

Wavelet coherence analysis of PM2.5 variability in response to meteorological changes in South Asian cities

Assessment of trends and variability of atmospheric particles can help set the target for pollution reduction, robust air-pollution and climate change policy decision-making, and clean air. This study investigated the recent trends and variability of Particulate Matter 2.5 (PM2.5) concentrations led by meteorological factors in fifteen major South Asian cities. It comprehensively assessed the influence of climatic factors through multiple statistical and time-frequency models. Trends were identified using the Mann-Kendal Test and innovative trend analysis methods. This study found the most critical air quality condition in Lahore (105.43 μg/m3), safe condition in Ho Chi Minh City (25.97 μg/m3), and most of the cities experience unhealthy to very unhealthy air conditions during winter. PM2.5 levels exhibited ascending trends in Dhaka, Jakarta, Lahore, Karachi, and Islamabad, while descending trends in Delhi, Mumbai, Hyderabad, Kolkata, Chennai, Kathmandu, Rangoon, Hanoi, Vientiane, and Ho Chi Minh City. Statistical models such as linear regression, Pearson's correlation, and Spearman rank correlation were applied to determine the influence of temperature, rainfall, humidity, and windspeed on PM2.5 concentrations. Despite the differences in climate conditions, PM2.5 concentrations were most sensitive to humidity, followed by temperature, rainfall, and windspeed across most cities. Most cities showed a negative relationship between PM2.5 and meteorological factors. Bi-wavelet coherence (WC) analyses were performed to investigate how the frequency components of PM2.5 and meteorological factors relate to each other over time. This WC analysis showed a high correlation with phase and antiphase correlations and demonstrated that all meteorological factors have influenced PM2.5 concentrations over time.

Field tests on large-scale instrumented piles driven in chalk: results and interpretation

The design of large open steel piles driven at chalk sites suffers from considerable uncertainty, leading to major difficulties in many significant onshore and offshore projects. This paper describes recent instrumented driving, monotonic testing to failure, and restrike tests conducted on large open steel piles driven in primarily low- to medium-density chalk at a site in North-western France. The experiments are described and interpreted with reference to a high-quality site characterisation, dynamic and static methods of test analysis, and alternative predictive design approaches. Important new conclusions flow regarding driving behaviour, the set-up that took place over up to 65 days after installation and the resistances available under compression and tension loading. Surprisingly large differences are shown between tension and compression shaft capacity, which are postulated to be due to Poisson straining in the steel pile shaft and its interaction with the surrounding chalk mass. The field tests contribute to building a high-quality dataset that allows proposed axial capacity design methods to be tested and potentially refined to provide reliable and representative design tools.

The Macroeconomic Factors on Malaysia’s Future Crude Palm Oil (FCPO)

Over the past few years, there has been much interest regarding the Futures Crude Palm Oil (FCPO) in Malaysia. Its volatility in particular, has drawn a lot of concern and has become the focus of discussion in several studies. This study attempts to contribute to the research by examining the macroeconomic variables on Malaysia’s Crude Palm Oil from the year 1990 to 2021. It is crucial to identify the factors in order to have a better control regarding the FCPO price uncertainties. The primary question that is being addressed here is whether the macroeconomic variables affect the price of FCPO. Moreover, a selection of independent variables was chosen in this study, namely Gross Domestic Product (GDP), Interest Rate (IR) and Inflation Rate (CPI). Meanwhile the dependent variable would be FCPO price. All data were sourced from The World Bank and Trading Economics. For analysis, this study employed the methods of Descriptive Analysis, Regression Analysis, Normality Test and Correlation Analysis. Overall, the results found that GDP and IR have a significant and positive relationship with the price of FCPO, with IR as the most significant variable. The study also revealed that CPI has no significant relationship with the price of FCPO and, in fact, negatively affected it. The results of this research may assist the Malaysian government, as well as private and palm oil sectors to take better initiatives to control the volatility of FCPO and boost the growth of CPO in Malaysia.

Impacts of Climate Change on Natural Runoff in the Yellow River Basin of China during 1961–2020

The change in natural runoff is highly relevant to total river flow dispatch and water resource utilization in the Yellow River Basin (YRB). Based on the annual mean temperature and total precipitation records from 70 meteorological stations from 1961–2020, the impact of climate change on the natural runoff of the YRB is investigated using the Mann-Kendall (M-K) test and Bivariate Wavelet analysis methods. Results show that the annual mean temperature over the YRB increased by 0.33 °C decade−1 during 1961–2020, with a warming rate of more than 0.40 °C decade−1 observed in its northern part. The annual total precipitation increases by 10–20 mm decade−1 in the northwest YRB, while it decreases by 20–30 mm decade−1 in the southeast YRB. The result of the M-K test shows abrupt variations in temperature and natural runoff, especially in the 1980s and 1990s. The decrease in natural runoff is closely tied to the increase (decrease) in temperature (precipitation), especially for the period 1993–2020. The bivariate wavelet coherence analysis further suggests that the decrease in the natural runoff, which has persisted over the past 60 years, is primarily driven by precipitation reduction rather than regional warming. In the stage of rapid warming, the inter-decadal influence of precipitation on natural runoff gradually changes to the influence of inter-annual fluctuation. The finding contributes to providing an important scientific basis for evaluating the optimal allocation of water resources in arid and semi-arid areas against the background of climate change.

Design and Optimization of a Liquid Cooling Thermal Management System with Flow Distributors and Spiral Channel Cooling Plates for Lithium-Ion Batteries

In this study, a three-dimensional transient simulation model of a liquid cooling thermal management system with flow distributors and spiral channel cooling plates for pouch lithium-ion batteries has been developed. The cooling plates play the role of uniforming temperature distribution and reducing the maximum temperature within each battery, while the flow distributors have the function of reducing the temperature difference between batteries in the battery module. The accuracy of the thermophysical properties and heat generation rate of the battery was verified experimentally. The optimal structure and cooling strategy of the system was determined by single factor analysis as well as orthogonal test and matrix analysis methods. The optimal solution resulted in a maximum battery module temperature of 34.65 °C, a maximum temperature difference of 3.95 °C, and a channel pressure drop of 8.82 Pa. Using the world-harmonized light-duty vehicles test cycle (WLTC) conditions for a battery pack in an electric car, the performance of the optimal battery thermal management system (BTMS) design was tested, and the results indicate that the maximum temperature can be controlled below 25.51 °C and the maximum temperature difference below 0.21 °C, which well meet the requirements of BTMS designs.

The Effect of Work Facilities and Motivation on Teacher Performance at SDIT Tunas Ilmu Tanjungpinang

The purpose of this study was to determine the influence of work facilities and motivation on teacher performance at SDIT Tunas Ilmu Tanjungpinang. Teacher performance is the ability and effort of teachers to carry out learning tasks as well as possible in planning teaching programs, implementing learning activities and evaluating learning outcomes. This research uses quantitative methods. The research sample used was a saturated sample of 50 people. The data collection technique in this study was to use a 5-point likert scale in the form of a questionnaire with a total of 30 questions. The data analysis method is carried out using the validity test analysis method, reliability test, normality test, and hypothesis test. The results of this study show that work facilities affect teacher performance with a significant level (0.001 &lt; 0.05), and motivation affects teacher performance with a significant level (0.000 &lt; 0.05), the conclusion of this study is that there is an influence of work facilities and motivation together on teacher performance at SDIT Tunas Ilmu Tanjungpinang with a significant level (0.000 &lt; 0.05).

Research and Analysis of One-button Sequential Control for GIS

One-button sequential control is one of the advanced applications of the intelligent substation, which is the key technology to promote the deep integration of modern information technology and power grid technology and to construct intelligent operation and inspection systems. Traditional switching depends on manual operation and has a great risk of misoperation. The application of one-button sequential control can effectively reduce misoperation and improve the safety level of power grid switching operations. Through the analysis and research on the key technology of one-button sequential control and combined with the action characteristics and position requirements of the moving contact of disconnector in the opening or closing process, the test analysis method and test control technical requirements of the one-button sequential control are put forward, which provides a certain technical basis for the control and design of the one-button sequential control in the future.