Normal Stress Levels Research Articles

Исследование распределения нормальных контактных напряжений в очагах деформации при горячей прокатке полос из конструкционных низколегированных сталей для повышения стойкости рабочих валков

Introduction. During the operation of the working rolls of the finishing groups of continuous wide-strip hot rolling mills, normal contact stresses have a decisive influence on its resistance and strength, especially when rolling a range of low-alloy structural steels with a minimum thickness range of 5.5–2.0 mm, which does not correspond to the passport characteristics of such mills. The subject of the study. Previously performed studies of the stress-strain state of the rolled strip in the deformation zones make it possible to estimate the level of normal contact stresses acting on the working rolls during hot rolling of strips of low-carbon steels. The paper discusses the results of the study of the stressed state of strips of low-alloy structural steels in contact with rolls, taking into account the features of the chemical composition of the metal and changes in its elastic properties during deformation at hot rolling temperatures. The results obtained are applicable to the evaluation of the contact strength of the finishing rolls of the rolling mill. The purpose of the work is to investigate the distribution of normal contact stresses in the deformation zones during hot rolling of strips of low-alloy structural steels to ensure high resistance of the working rolls. Material and methods. The study is based on the elastic-plastic model and equations for calculating normal contact stresses for each section of the deformation zone. The specificity of variation of Young's modulus (modulus of elasticity) of low-alloyed structural steels in accordance with certain hot rolling temperatures is studied in detail, and the contact strength of high-chromium cast iron work rolls is evaluated. Results and discussion. A reliable regression equation is obtained for determining the values of the Young’s modulus of the rolled strip as a function of changing hot rolling temperatures. The results of a numerical experiment are presented in the form of calculating the maximum normal contact stresses using the elastic-plastic model of the deformation zone and assessing the contact strength of the work rolls based on actual rolling conditions on an operating mill. New improved technological modes of hot rolling of low-alloy structural steels (0.1 C-Cr-Si-Ni-Cu, 0.18 C-Cr-Mn-Ti and 0.14 C-2 Mn-N-V) are proposed, which make it possible to reduce the maximum contact stresses and increase the resistance of the working rolls.

Investigation of the Brittleness and Sensitivity of the Gypseous Sand Improved by Nano-clay

This study examines the brittleness index and sensitivity ratio of two gypseous sand soils under saturation conditions improved by nano-clay. The soil samples were obtained from the cities of Al-Najaf and Tikrit containing 29% and 55% gypsum, respectively. The tests were performed on remolded specimens in a direct shear box. The soil specimens were examined mainly under saturated conditions for both different soil and nano-clay contents (0, 2, 5, and 7 %) under three normal stress levels: 25, 50, and 100 kPa. Additional tests were performed under dry soil conditions for comparison. The calculations of the brittleness index and sensitivity ratio of the saturated soil specimens were dependent on the newly suggested definitions of the peak values of the shear stress. The tP is the peak value in the dry condition, whereas the tR is the peak value in the saturation condition. The results emphasize that the values of the brittleness index and sensitivity ratio require more attention to the possibility that the soil is brittle owing to increased gypsum dissolution and the demolition of the soil structure. The brittleness index and sensitivity ratio increased with increasing gypsum content and decreased with increasing nano-clay content and average stress levels. The optimum percentage of nano-clay for both soil specimens was found to be 5%.

Description of Stress and Cognitive Function in Patients Non-Hemorrhagic Stroke at Tugurejo Hospital in 2022

Stroke is the main cause of death in Indonesia, the incidence has increased from 7% to 10%, of which 74% have ischemic strokes. Stress is common in stroke patients. According to research conducted, 58.8% of stroke survivors experienced severe stress, and 60% of stroke survivors experienced decreased or decreased cognitive function after stroke. The research objective was to describe stress and cognitive function in order to reduce stress levels and cognitive function in non-hemorrhagic patients at Tugurejo Hospital in 2022. This type of research is a quantitative descriptive analysis with a cross sectional design. The study population consisted of post-stroke patients who were diagnosed in 2022 by doctors at Tugurejo General Hospital and met the inclusion criteria, namely the Mini Mental State Exam Test Questionnaire (MMSE) and Depression Anxiety Stress Scales (DASS-21) as research instruments, then the data were analyzed using univariate analysis. The total sample consisted of 40 respondents who were analyzed by univariate. The results of the study describing stress levels in non-hemorrhagic stroke patients at Tugurejo Hospital in 2022 showed that 35% had normal stress levels and 65% had abnormal stress levels. while the picture of cognitive function in non-hemorrhagic stroke patients showed normal results in 32% and impaired cognitive function in 67.5%. Description of stress and cognitive function in non-hemorrhagic stroke patients at Tuguurejo General Hospital in 2022. Based on risk factors, gender, age, education, occupation, pre-existing conditions and stroke onset, the results showed abnormal levels of stress and disruption of cognitive function.

Perceived Social Support and Depression, Anxiety and Stress in Pregnant Women Diagnosed With Foetal Anomaly.

To examine the relationship between perceived social support level and depression, anxiety and stress in pregnant women diagnosed with foetal anomaly. This descriptive and correlational study was conducted in an advanced prenatal evaluation unit of a university hospital between December 2021 and May 2022. The study data collected from 131 pregnant women through a personal information form, depression, anxiety and stress scale (DASS-42) and multidimensional scale of perceived social support (MSPSS). Most of the pregnant women were in the second trimester of pregnancy, and more than half had been advised by a healthcare professional to terminate their pregnancy. Overall, the pregnant women reported moderate levels of social support, while their depression, anxiety and stress levels varied. There was a weak negative correlation between perceived social support from family, friends and multidimensional sources with stress, but the effect rate was low. Most pregnant women diagnosed with foetal anomaly have normal levels of depression, stress and anxiety. There is a weak negative correlation between perceived social support and stress, with family and friend support affecting stress levels at a low rate. Professional support should be provided, and both the woman's mental health and social support mechanisms must be evaluated. This study highlights the importance of social support in managing stress among pregnant women with foetal anomalies. While most women had normal levels of depression, anxiety and stress, increased social support from family and friends was shown to reduce stress. The findings underscore the need for healthcare professionals to assess and strengthen mental health and social support systems in this vulnerable population, informing interventions to improve psychosocial outcomes. This descriptive and correlational study adhered to the CONSORT guidelines for reporting non-randomised trials. No patient or public contribution.

Physics informed neural network can retrieve rate and state friction parameters from acoustic monitoring of laboratory stick-slip experiments

Various machine learning (ML) and deep learning (DL) techniques have been recently applied to the forecasting of laboratory earthquakes from friction experiments. The magnitude and timing of shear failures in stick-slip cycles are predicted using features extracted from the recorded ultrasonic or acoustic emission (AE) signals. In addition, the Rate and State Friction (RSF) constitutive laws are extensively used to model the frictional behavior of faults. In this work, we use data from shear experiments coupled with passive acoustic (variance, kurtosis, and AE rate) interleaved with active source ultrasonic monitoring (transmitted wave amplitude) to develop physics-informed neural network (PINN) models incorporating the RSF law and AE rate generation equation with wave amplitude serving as a proxy for friction state variable. This PINN framework allows learning RSF parameters from stick-slip experiments rather than measuring them through a series of velocity step experiments. We observe that when the stick-slip cycles are irregular, the PINN models outperform the data-driven DL models. Transfer learning (TL) PINN models are also developed by pre-training on data collected at one normal stress level followed by forecasting shear failures and retrieving RSF parameters at other stress levels (i.e., with different recurrence intervals) after retraining on a limited amount of new data. Our findings suggest that TL models perform better compared to standalone models. Both standalone and TL PINN-estimated RSF parameters and their ground truth values show excellent agreements thus demonstrating that RSF parameters can be retrieved from laboratory stick-slip experiments using the corresponding acoustic data and that the transmitted wave amplitude provides a good representation of the evolving frictional state during stick-slips.

Association between Stress Levels and Functional Dyspepsia among Medical Students During the COVID-19 Pandemic: A Study of Indonesian Christian University

Background: Stress is a problem that often occurs among students. The high incidence of stress in students can interfere with students' effectiveness in carrying out their lecture activities. Stress in students not only affects the quality of learning but can also affect the physical condition of students, one of which is the occurrence of gastrointestinal disorders, one example of which is dyspepsia. Aims: This study aims to determine whether there is a relationship between stress levels and functional dyspepsia in students at the Faculty of Medicine, Indonesian Christian University class of 2020. Study Design: This research uses an observational analytical research design method with a cross-sectional approach. The main data source is primary data obtained through questionnaires taken online via Google Forms. Place and Duration of Study: The research was conducted at the Indonesian Christian University located in Cawang, East Jakarta. Time of research in September 2022. Methodology: The population in this study was 137 students from the Faculty of Medicine, Indonesian Christian University class of 2020. The sample was taken using a simple random sampling technique totaling 103 people determined using the Slovin formula with an uncertainty percentage of 5%. Results: From the results of data collection on 103 respondents who were FK UKI students Class of 2020, around 65% or 67 respondents were identified as having normal stress levels and as many as 64 students (62%) had symptoms of functional dyspepsia. Based on the results of the bivariate analysis, it was found that there was a relationship between the level of stress and the incidence of dyspepsia experienced by FK UKI students class of 2020 with the results of the chi-square test, namely p = 0.003 < sig 0.05 Conclusion: There is a significant relationship between stress levels and functional dyspepsia. This certainly cannot be taken lightly because the incidence of functional dyspepsia can have fatal consequences which can disrupt the sufferer's activities and productivity. Therefore, it is very necessary to manage emotions (stress levels) both by the sufferer himself and with professional help.

Prevalence of Psychological Stress and Associated Risk Factors Among Hypertensive Patients in Jordan: Cross-Sectional Study

Hypertension is considered one of the chronic illnesses that affect many individuals across the globe. It has been evident that stress is associated with hypertension. The current study aimed to assess the prevalence of stress among hypertensive men as well as determine the risk factors causing psychological stress in Jordan. This study used a descriptive correlation cross-sectional design. The researchers recruited 200 patients with hypertension from six hospitals located in the central part of Jordan. Data was collected from the participants through self report questionnaire. The study results revealed that the total scores of perceived stress among the study participants ranged from 4 to 42 (M= 18.17; SD= 8.18). Almost half of the study participants (40%) perceived normal level of stress (0 ≤ total stress subscale ≤ 14). The findings showed that gender (t = -1.99, B = -2.90, p = 0.048), educational Level (t = -2.39, B = -2.39, p = 0.02), health Status (t = 3.08, B = 1.67, p = 0.002), and sleep (t =2.45, B = 3.22, p = 0.02) were the significant predictors of stress among Jordanian patients with hypertension. This study contributed to the existing body of knowledge and can be considered as a baseline for future researcher in the area of stress. The health care providers in various medical departments should make effort to provide optimal care for patients with hypertension that directed toward decreasing the level of stress.

Assessment of concrete-to-concrete shear bond behavior using 3-D direct shear testing

The interfaces that develop when fresh concrete is poured onto existing substrates are noted for their vulnerability and influence on the durability and integrity of the composite structure. Studies on the shear bond properties and failure mechanisms of such composite concrete-to-concrete joints under normal stress are essential for developing predictive and numerical models that accommodate various levels of joint substrate roughness. This study aims to use an innovative 3D shearing box, BCR3D, to analyze the shear behavior of concrete-to-concrete joints under direct shear tests at a constant normal stress. The influence of the degree of surface roughness on the pure shear behavior of these joints was assessed at a normal stress level of 1 MPa. The substrate post-hardening surface morphology was evaluated using a high-resolution laser profilometer. Statistical surface roughness parameters were computed using MATLAB. A parametric study was carried out involving bond strength, residual shear stress, contractive-dilative behaviors, and total fracture energy. Results showed that bond strength, dilative normal displacement, and total fracture energy were proportional to the substrate surface roughness. Residual shear stress was not affected by the initial surface roughness. Dilative normal displacements were more significant for specimens with higher surface substrate roughness due to interlocking, with values reaching up to 1.77 mm. Joints with high substrate surface roughness exhibited similar bond strength and fracture energy to those obtained from the monolithic specimens, underscoring the significance of substrate preparation before casting new concrete layers.

Factors influencing sexual interest in postmenopausal Asian women.

The sexual interest of postmenopausal women is a crucial aspect of their overall well-being. Despite its importance, factors influencing postmenopausal sexual interest, particularly in Asian women, remain understudied and poorly understood. To investigate the various factors influencing sexual interest in postmenopausal women in Malaysia. A cross-sectional study was conducted of postmenopausal women attending a gynecology or primary care clinic in a teaching hospital in Malaysia. We investigated how interpersonal dynamics and cultural norms-including the physical and mental health of women and their partners, as well as their sexual values-affect menopausal sexual interest as measured by the Menopausal Sexual Interest Questionnaire. Women in the study reported an average sexual interest, with a mean score of 32.8 (SD, 9.4) out of 70 on the Menopausal Sexual Interest Questionnaire. Multivariable analysis results showed that higher personal sexual values (odds ratio [OR], 2.65; 95% CI, 1.26-5.61) and spousal sexual values (OR, 2.68; 95% CI, 1.22-5.86) were significantly associated with higher menopausal sexual interest. There was a positive correlation between the physical fitness of spouses and menopausal sexual interest, with women who rated their spouses as very fit or fit (OR, 3.22; 95% CI, 1.15-9.00) or moderately fit (OR, 2.63; 95% CI, 1.05-6.63) showing higher menopausal sexual interest as compared with those whose spouses were very unfit or unfit. Women with normal stress levels (OR, 5.89; 95% CI, 1.03-33.62) and mild to moderate stress levels (OR, 8.13; 95% CI, 1.53-43.22) reported higher menopausal sexual interest. This study emphasizes a holistic approach to postmenopausal sexual health, highlighting the significance of promoting positive sexual values, improving physical fitness, and managing stress. Health care providers should educate, counsel, and collaborate interdisciplinarily, ensuring culturally sensitive care tailored to individual needs. The study's strength lies in its provision of valuable insights into factors affecting sexual interest among postmenopausal Asian women, enhancing comprehension of holistic sexual health approaches. However, reliance on self-assessments may introduce response bias influenced by social desirability, and limited generalizability stems from single-site data collection. Our study highlights the significance of adopting a holistic approach to addressing sexual health in postmenopausal women, which includes promoting positive sexual values, improving physical fitness, and managing stress.

Pattern of Utilization of Antenatal Care Services and Adherence Among Females Following Up at Primary Healthcare Centers in Al-Ahsa.

Background Antenatal care (ANC) is a crucial component of maternal and child health, yet disparities in utilization persist globally. This study aimed to assess the patterns of ANC service utilization and adherence among pregnant women attending primary healthcare centers (PHCCs) in Al-Ahsa, Saudi Arabia. Methodology A quantitative, cross-sectional study was conducted among 277 women attending PHCCs in Al-Ahsa. Data were collected through structured questionnaires, assessing demographic characteristics, ANC follow-up patterns, structural and personal barriers, and mental health conditions using the Depression, Anxiety, and Stress Scale. Results Significant regional variations in ANC follow-up patterns were observed, with higher proportions of pregnant women attending ANC in the Middle and Eastern regions. Prominent structural barriers included transportation challenges (structural barrier 3, 61.0%) and limited service availability (structural barrier 6, 56.0%), while personal barriers encompassed transportation problems (personal barrier 6, 36.8%) and forgetfulness regarding appointments (personal barrier 4, 19.9%). Mental health assessments revealed predominantly normal levels of depression, anxiety, and stress, with some regional variations in distress levels. Conclusions The study highlights regional disparities in ANC service utilization and adherence, influenced by structural barriers, personal barriers, and mental health conditions. Tailored interventions addressing these barriers, improving access to care, and providing targeted support are crucial for enhancing ANC service utilization and promoting maternal and child health in Al-Ahsa.

Particle shape descriptors as a tool for classification of grain breakage

This study explores particle breakage of a calcareous sand, utilising dynamic image analysis and direct shear tests at varying normal stress levels to analyse the sand crushing mechanism. Tests were arrested at four phase transition points encountered during shear. Particle breakage was traced along a proposed scale based on the literature. Distinct behaviours in shape descriptors for particles of different diameters were observed under changing stress conditions. Agglomerated particle-level behaviour indicates that applied stress levels lead to different soil responses; at low stress, grains roll or slide, whereas at high stresses, grain movement is restricted. Particle breakage was evident even at minimal stress, with increasing grain size reduction as shear strain and stress levels heightened. This study introduces a parameter loading intensity (LI), amalgamating the effects of force chains and loading duration to model grain crushing. Relationships among the shape-angularity group indicator (SAGI), convexity (Cx) and sphericity (S) were also established, enabling calculation of these descriptors, after any loading intensity is applied, based on the initial values. Finally, a methodology for forecasting changes in S and Cx, under any given LI for materials with a known SAGI is presented.

Characteristics of Stress Levels, Learning Motivation, and the Level of Knowledge

Medical students face a variety of stressors, such as the rigorous medical curriculum, competition for their desired specialty, and adherence to the school’s moral and ethical standards. This study aimed to describe the characteristics of motivation and stress of preclinical medical students. The study gathered questionnaires from 250 preclinical medical students from December 2023 to January 2024. The collected data were related to motivation, stress level, CBT/Socca score, and Learn strategy. The sample is 250 participants, most participants were female (70.4%), aged < 20 years old (98.4%), and had medical interests by their own wishes (77.6%). Most preclinical students in the MSLQ questionnaire had moderate motivation (76.8%) and moderate learning strategy (73.6%), and the results were good in the DASS-42 questionnaire with normal depression, anxiety, and stress (69.2%, 45.2%, 70.0%). The CBT vs SOCCA test scores had very different results; the SOCCA score was lower than CBT score SOCCA= E (24 %) with an average value of 60.50 ± 21.03 vs. CBT= A- (20.0%) with an average value of 63.10 ± 11.37. The characteristics of medical faculty students are normal stress levels, moderate learning motivation, and the SOCCA score was lower than the CBT score.

Depression, anxiety, stress, and current e-cigarette use: Results from the Truth Longitudinal Cohort of youth and young adults (2022−2023)

ObjectiveTo examine associations between depression, anxiety, and stress, as measured by the Depression, Anxiety and Stress Scale (DASS-21) scale, with current e-cigarette use. MethodsData from the Truth Longitudinal Cohort – a nationally representative sample of youth and young adults – was collected between October 2022 to February 2023. The analytic sample was comprised of participants who provided information on e-cigarette use and the DASS-21 scale (N = 4198). Chi-square statistics were used to determine differences by current e-cigarette use across covariates and DASS-21 items. Logistic regression analyses were applied to the cross-sectional data to determine which scales predicted current e-cigarette use, adjusted for the effects of age, gender identity, race and ethnicity, parental educational attainment, perceived financial situation, and current use of alcohol, marijuana, and other tobacco use. ResultsThose who had severe/extremely severe levels of depression, anxiety, and stress had greater odds of current e-cigarette use, relative to those who had normal levels of depression, anxiety, and stress, even after adjusting for covariates. Results also demonstrated associations between age, race/ethnicity, parental education, and current use of alcohol, marijuana, and other tobacco products with current e-cigarette use. LimitationsCross-sectional analyses of self-reported data limit the ability to determine directionality of effects between depression, anxiety, stress, and current e-cigarette use. DiscussionMore severe levels of depression, anxiety, and stress were associated with a greater likelihood of current e-cigarette use. Future research is needed to evaluate changes in e-cigarette use, in response to depression, anxiety, and stress symptomatology.

Advantages of using DIC for capturing mechanical shear sliding behaviour of the FRCM strengthened masonry

This paper aims to analyse the advantages of using Digital Image Correlation (DIC) method to capture the effects of the FRCM on masonry wall shear failure. In the scientific literature, most of the experimental programs is focused on strengthening against flexural failure by means of bending tests and against shear, diagonal cracking, by means of diagonal compression tests. The shear failures are one of the main failure modes for the in-plane behaviour of masonry walls in case of horizontal loads. This study primarily focuses on experimentally determining the capacity of clay brick masonry under sliding shear loads for different normal stress levels with a standard test method. The assessment of shear capacity is based on a Mohr-Coulomb failure criterion depending on the external axial load, the internal friction angle and the cohesion values for unreinforced masonry. The experimental tests have been carried out on both unreinforced and strengthened specimens. The results of the tests demonstrate that FRCM, despite the reduced anchorage length in the tests, can significantly enhance the structural performance of masonry structures for sliding shear failure mode. In addition, DIC method is used to analyse, in greater detail, the cracks and the strain evolution in order to analyse the failure of specimens.

TECTONOPHYSICAL ZONING OF ACTIVE FAULTS OF THE BAIKAL RIFT SYSTEM

Tectonophysical zoning of active faults of the Baikal rift system (BRS) was performed based on the degree of hazard caused by the generation of earthquakes of magnitude 7.0 and higher. The first basis for this procedure was the results of the natural stress state reconstruction, earlier performed from seismological indicators of rupture deformations (earthquake focal mechanisms). The second important element of fault zoning was electronic maps of active faults of Eurasia hosted on the GIN RAS sever. Within the algorithmic framework for Rebetsky’s method of cataclastic analysis, both of these datasets allowed calculating the Coulomb stresses for the segments of the BRS faults. During the study, a development of the cataclastic method has been carried out in using a diagram of brittle fracture as the Mohr–Coulomb model, considering a decrease in the range of positive Coulomb stress values with an increase in effective normal stress levels. Such an approach provides a more reliable identification of the fault segments with the maximum Coulomb stress levels. The performed calculations showed that in the BRS crust there are several up to 50 km long fault segments having critically high (80–100 % of the maximum) and high (40–80 % of the maximum) Coulomb stress levels. It is these corebased hazardous zones that are considered as places where seismogenic ruptures of future М>7.0 earthquakes may start. There have been distinguished three zones that present such hazard: 1) in the western segment of the BRS in the western part of the Tunka Valley in the Tunka, Khamardaban-Mondy and Baikal-Mondy fault systems; 2) in the Selenga River delta in the Proval, Delta, Ust-Selenga and Sakhalin-Enkhauk fault systems; 3) within the northeastern flank of the BRS on the fault system of the Muyakan basin (along the North Muya ridge). It is proposed to perform tectonophysical monitoring of changes in the stress state of these three zones and make observations of their surface motions using remote sensing methods.

Effect of deposition rate and annealing on Nb thin film growth on Cu substrate: Molecular dynamics simulation

Molecular dynamics (MD) simulations are performed to study the growth mechanisms of Nb thin film on Cu substrate. In this investigation, we provide insights and information about the quality of the deposited Nb thin film by analyzing the growth mode, stress, and evolution of its microstructural and morphological properties by considering different deposition rates and thermal annealing processes. The results show that the growth of Nb atoms on the Cu substrate follows the island mode. The interface analysis reveals the presence of a nucleation phenomenon, moreover, the results indicate that the first layer of Nb film remains incomplete until approximately the amount of 4 monolayers of Nb is deposited. The analysis of interdiffusion indicates that Nb penetration is initially limited to the first Cu layer. However, after annealing, there is a significant increase in Nb atom penetration and a clear rearrangement of Nb within each layer of the film. The film adopts a BCC structure, with crystallinity rates varying based on the deposition rate. The highest crystallinity rate is observed at 5 atoms/ps, and annealing further increases these percentages. Deposition at different rates leads to different levels of compressive normal and biaxial stress.

Macro-micro investigation on the coefficient of friction on the interface between steel and cast-in-place UHPC

The interface friction force between steel and Ultra-high performance concrete (UHPC) can significantly enhance the shear loading capacity and fatigue performance of steel-UHPC composite structures. Current research on interface friction primarily focuses on the coefficient of friction (COF) on steel-concrete interface. However, using the COF of steel-normal concrete (NC) interface to assess the steel-UHPC interface performance might be debatable and lack accuracy, due to the substantial differences in material properties and compositions between UHPC and NC. In this study, the COF on the interface between the steel plate and cast-in-place UHPC was investigated, and the effects of the steel plate roughness and interface normal stress on the COF were considered. The COF of steel-UHPC was compared with those of steel-NC. The steel plate surface microstructure was also tested using a microscope after experiments. It is recommended that the COF between UHPC and NC and a natural steel plate should be considered as 0.803 and 0.704, respectively, under interface normal stress levels ranging from 0.5 MPa to 9 MPa. The adopted COF in the existing numerical analyses for steel-UHPC structures was conservative, underestimating the value by 37.73 % to 62.64 % compared to the recommended value in this paper. Moreover, when the steel plate roughness of steel-UHPC specimens increased by 1.324 times, the maximum increase in the COF was 11.75 %. However, when the interface normal stress increased by 17 times, the COF on the steel-UHPC interface decreased by a maximum of 12.57 %. Compared to steel-NC specimens, the COF of steel-UHPC showed a maximum increase of 14.25 % under an interface normal stress of 0.5 MPa and 12.98 % under an interface normal stress of 9 MPa.

Reliability Assessment Method Based on Small Sample Accelerated Life Test Data

Aiming at the problems of small sample size, few test failure data and low reliability evaluation efficiency in accelerated life test of high-reliability and long-life products, an improved virtual augmentation Bootstrap-Bayes reliability evaluation method based on small sample accelerated life test data was proposed. Firstly, the test data under various stress conditions are augmented by virtual fusion. Secondly, the empirical distribution function and bootstrap sampling method are improved, and the kernel density estimation method is used to fit the density distribution of test data as prior information. Then, the parameter estimates of the test data are obtained by Gibbs sampling combined with Bayes formula. Finally, the reliability index under normal stress level is obtained by accelerating model extrapolation. The feasibility of the proposed method is verified by the accelerated life test data of a type of Ship communication equipment.

Gambaran Risiko Dismenore Primer Pada Mahasiwa Tingkat Akhir Universitas ‘Aisyiyah Surakarta

Final-year students completing their final projects often experience anxiety. Risk factors underlying the occurrence of dysmenorrhea include age at menarche, longer than normal menstrual duration, smoking habits, exercise habits, and stress levels. Research Objective: To describe the incidence of dysmenorrhea, age at menarche, menstrual duration, and stress levels among final-year students at Universitas Aisyiyah Surakarta. Method: This study is a quantitative descriptive type using simple random sampling. The study involved 74 respondents meeting the inclusion criteria of final-year female students who have experienced menstruation; exclusion criteria included those willing to participate and not suffering from reproductive organ diseases. Results: Incidence of dysmenorrhea: most respondents experienced dysmenorrhea with mild pain levels, totaling 34 respondents (47.3%). Age at menarche: most respondents experienced menarche at an ideal age, totaling 48 respondents (64.9%). Menstrual duration: most respondents had a normal menstrual duration, totaling 69 respondents (92.2%). Stress levels: most respondents experienced moderate stress, totaling 52 respondents (70.3%). Conclusion: Regarding dysmenorrhea, most respondents experienced mild dysmenorrhea; concerning age at menarche, most respondents had an ideal age; regarding menstrual duration, most respondents had a normal duration; concerning stress levels, most respondents experienced moderate stress.

Assessment of Anxiety, Stress, and Depression Among COVID-19 Survivors After 40 Months in the Kurdistan Region of Iraq: An Online Cross-Sectional Study.

COVID-19 survivors often experience significant and pervasive psychological distress. This study aimed to investigate the prevalence and demographic factors affecting anxiety, stress, and depression levels among COVID-19 survivors in the Kurdistan region of Iraq. This online cross-sectional study was conducted from August 1, 2023to December 17, 2023, in the Kurdistan region of Iraq, including Erbil, Sulaymaniyah, and Duhok. Purposive sampling was used to collect data using an online survey. The survey included demographic information and the Depression, Anxiety, and Stress Scale - 21 Items (DASS-21). Statistical analysis was performed using Stata version 12(StataCorp LLC, College Station, TX), with frequency and percentage used for categorical variables and mean and standard deviation for quantitative variables. Ordinal regression analyses were conducted to assess associations between demographic factors and mental health outcomes. A p-value of less than 0.05 was considered statistically significant. A total of 783 participants were enrolled in the study. The mean score for anxiety was 11.62 ± 4.71, indicating moderate levels. For depression, the mean score was 11.54 ± 5.21, indicating mild levels, and for stress, the mean score was 14.0 ± 5.78, indicating normal levels. Younger individuals (15-27) showed higher stress (Estimate: 18.96, P=0.001) and anxiety (Estimate: 2.79, P=0.001) levels compared to older age groups. Males reported significantly lower stress (Estimate: -1.01, P=0.001), anxiety (Estimate: -1.29, P=0.001), and depression (Estimate: -0.72, P=0.001) than females. Participants with a diploma had lower anxiety (Estimate: 0.65, P=0.004) and stress (Estimate: 0.77, P=0.002) levels compared to those with only elementary education. The study found moderate levels of anxiety among COVID-19 survivors, with mild depression and normal stress levels. To address these issues, it is recommended that policymakers develop targeted mental health interventions. Healthcare providers should focus on early identification and treatment, providing personalized counseling and support to enhance coping mechanisms and overall psychological well-being. By implementing these measures, mental health outcomes for COVID-19 survivors in Iraq can be significantly improved.