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Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mohammed Jayed Alenzi,1,* Ahmed S Alshalash,1 Abdulmohsen Nayef Al-enzi,2 Fahad Suhayman Al-anazi,2 Nawaf Mohammed Al-anzi,2 Khalid Omar Alsharari,2 Abdulhadi Abdullah Alanazi,2 Sultan Mohammed Alanazi,2 Ashokkumar Thirunavukkarasu3,* 1Department of Surgery, College of Medicine, Jouf University, Sakaka, Aljouf, Saudi Arabia; 2Medical Student, College of Medicine, Jouf University, Sakaka, Aljouf, Saudi Arabia; 3Department of Community and Family Medicine, College of Medicine, Jouf University, Sakaka, Aljouf, Saudi Arabia*These authors contributed equally to this workCorrespondence: Ashokkumar Thirunavukkarasu, Department of Community and Family Medicine, College of Medicine, Jouf University, Sakaka, 72388, Saudi Arabia, Tel +966-599739619, Email ashokkumar@ju.edu.saBackground: Assessment of parents’ awareness of testicular torsion (TT) is essential to plan for necessary awareness-raising campaigns by policymakers. Hence, the preventable loss of testis due to inadequate awareness can be avoided. We aimed to evaluate the awareness of TT amongst parents from the Aljouf region, KSA, and to assess their response to a potential torsion.Methods: We conducted a cross-sectional study among parents from the Aljouf region. The sample population was obtained using a consecutive sampling method. The present study used a pretested Arabic questionnaire. We used a statistical package for social science software for data analysis.Results: There were 320 parents who participated in different public places for the present study. Of the respondents, 10.6% of their children had sudden pain in the scrotum. More than half (52.2%) had never heard of testicular torsion, and 72.5% of parents agreed that they would seek immediate medical attention for severe testicular pain, but a low (42.5%) proportion of parents responded that they would seek help immediately. Nearly one-fourth of them responded that less than 6 hours is the critical time for repair. Parents who were knowledgeable at the critical time had more odds of presenting to a healthcare facility immediately for both mild (OR = 2.77, CI = 1.55– 4.03, p = 0.001) and severe (OR = 1.92, CI = 1.03– 3.63, p = 0.032).Conclusion: We found a lack of awareness of TT among Saudi parents. It is suggested to improve the knowledge among them through awareness-raising campaigns by the concerned health authorities through feasible methods. Furthermore, we recommend conducting a futuristic multicenter and exploratory study to find province-specific awareness.Keywords: testicular torsion, awareness, Saudi, pain, parents, critical time

The monkeypox virus (MPXV) has caused an unusual epidemiological scenario—an epidemic within a pandemic (COVID-19). Despite the inherent evolutionary and adaptive capacity of poxviruses, one of the potential triggers for the emergence of this epidemic was the change in the status of orthopoxvirus vaccination and eradication programs. This epidemic outbreak of HMPX spread worldwide, with a notable frequency in Europe, North America, and South America. Due to these particularities, the objective of the present study was to assess and compare cases of HMPX in these geographical regions through logistic and Gompertz mathematical modeling over one year since its inception. We estimated the highest contagion rates (people per day) of 690, 230, 278, and 206 for the world, Europe, North America, and South America, respectively, in the logistic model. The equivalent values for the Gompertz model were 696, 268, 308, and 202 for the highest contagion rates. The Kruskal–Wallis Test indicated different means among the geographical regions affected by HMPX regarding case velocity, and the Wilcoxon pairwise test indicated the absence of significant differences between the case velocity means between Europe and South America. The coefficient of determination (R2) values in the logistic model varied from 0.8720 to 0.9023, and in the Gompertz model, they ranged from 0.9881 to 0.9988, indicating a better fit to the actual data when using the Gompertz model. The estimated basic reproduction numbers ( R 0 ) were more consistent in the logistic model, varying from 1.71 to 1.94 in the graphical method and from 1.75 to 1.95 in the analytical method. The comparative assessment of these mathematical modeling approaches permitted the establishment of the Gompertz model as the better-fitting model for the data and the logistic model for the R 0 . However, both models successfully represented the actual HMPX case data. The present study estimated relevant epidemiological data to understand better the geographic similarities and differences in the dynamics of HMPX. [ABSTRACT FROM AUTHOR]

In this paper, the non-harmonic resonance of Bernoulli viscoelastic beams, Kirchhoff viscoelastic plates, Timoshenko viscoelastic beams, and Mindlin viscoelastic plates subjected to time-dependent exponentially decreasing transverse distributed load is investigated for the first time. The constitutive equations are expressed utilizing Boltzmann integral law with a constant bulk modulus. The displacement vector is approximated by employing the separation of variables method. The Laplace transformation is used to transfer equations from the time domain to the Laplace domain and vice versa. The novel point of the proposed method is to express, prove and calculate the critical time in which the displacement will be several times the displacement at time zero. In addition, this new method calculates the maximum deflection at the critical time, explicitly and exactly, without any need to follow the time-displacement curve with a low computational cost. Additionally, the proposed method introduces the critical range of time so that the responses are greater than the responses at time zero. [ABSTRACT FROM AUTHOR]

In order to comprehend the ageing characteristics profoundly and evaluate the ageing degree of cross-linked polyethylene (XLPE) cable insulation, the XLPE cable insulation is subjected to accelerated ageing experiment at 135 oC. The variation of elongation at break is characterized by the tensile test. The carbonyl concentration and antioxidant contents in XLPE are measured by Fourier transform infrared spectroscopy. Results show that the ageing of XLPE cable insulation exhibits critical time characteristic, namely elongation at break of XLPE decreases slowly and then decreases dramatically with ageing time. Meanwhile the carbonyl concentrations also increase slowly at first and then increases rapidly. The critical time is 2016h when aged at 135 oC. While the content of antioxidant gradually decreases without inflection point. Based on the chain free radical theory, the thermal ageing kinetics model considering the reaction of antioxidant is established, and the variation of antioxidant content and carbonyl concentration during the thermal ageing of XLPE cable insulation are furtherly calculated by simulation. Simulation results are in good agreement with the experimental results. The results indicate that the antioxidant content could reveal the ageing degree of XLPE insulation.

Coal spontaneous combustion is one of the important disasters affecting the development of coal-related industries. To understand the characteristics of various parameters of coal spontaneous combustion process in detail, a combination of experiment and numerical simulation was used to study the coupling characteristics of multiple physical parameters of coal low-temperature oxidation, the reliability of the numerical model is verified by the experiment. The evolution law of coal spontaneous combustion under different oxygen conditions is further explored, the results show that the established numerical model can well characterize the multi-parameter coupling characteristics of coal spontaneous combustion. The oxygen volume fraction decreases with the increase of coal temperature, and the CO and CO2 volume fractions increase with the increase of coal temperature. The gas consumption and production characteristics of coal oxidation reaction show hysteresis characteristics. The CO and CO2 produced by the coal oxidation reaction under different oxygen conditions increase with the increase of the oxygen volume fraction, and the change within 8 h has a linear relationship with the oxygen volume fraction. The distribution of oxygen inside the coal body presents a “stratified” feature. Taking 2 h as the critical time, the minimum temperature and the average temperature of the coal sample show different increasing trends. As the oxygen volume fraction decreases, the low temperature area in the coal body expands to the gas inlet area.

The widespread use of structural elements consisting of functionally graded (FG) materials in advanced technologies has led to extensive research. Due to the difficulties encountered during modeling and problem solving, the number of studies on the dynamic behavior of structural elements made of FG viscoelastic materials is quite limited compared to the number examining FG elastic materials. This study is one of the first attempts to solve the dynamical problem by the mathematical modeling of functionally graded viscoelastic plates (FG-VE-Ps) and viscoelastic media together with different initial conditions. FG-VE-Ps on viscoelastic foundations (VE-Fs) are assumed to be under compressive edge load in the longitudinal direction. The governing equations for FG-VE-Ps on VE-Fs are derived using Boltzmann and Volterra concepts. The problem is reduced to the solution of integro-differential equation system using the Galerkin method. Then, by performing Laplace transforms, new analytical expressions for the time-dependent deflection function and critical time at different initial conditions are found. The loss of stability of FG-VE-Ps on VE-Fs is modeled to cover three time-varying ranges: the first is the range in which the deflection function decreases; the second is the transition interval; the third is the increase range of deflection function, which leads to the loss of stability. The time corresponding to the sharp increase of the deflection function is defined as the critical time, and is determined both theoretically and numerically. The results are compared with the results obtained by various methods to confirm their accuracy. Finally, the effects of VE-Fs, VE material properties, and FG profiles on the critical time behavior of plates are studied numerically. [ABSTRACT FROM AUTHOR]

This paper study the influence of roughness of the tank base in the formation of air core vortex when liquid inside the cylindrical tank is rotated and subsequently drained. The vortex air core formation in drain tanks can lead to the blockage of drain port and can result in reduced discharge of draining liquid as an immediate consequence. The formation of such a vortex in propellant tanks of spacecraft and rockets will lead to underutilization of propellants and can adversely affect the performance of rocket engines. Ingestion of air core vortex in metal casting process can affect the mechanical properties of casted metal. Hence, suppression of air core vortex is inevitable in the fields of aerospace, metal casting and other hydraulic engineering systems. Current study makes use of roughness of the tank base to suppress vortexing which is the first of its kind and therefore, novel. Experimental investigations have been carried out at several values of roughness height and initial fluid rotation to study the characteristics of air core vortex. It is found that at the highest value of initial rotation provided to the liquid, air core vortexing can be subdued up to 25% by making use of base roughness. Current study also recommends drain tank manufacturers not to smoothen the tank base surface spending time at extra cost. In addition, applying roughness on the tank base will further weaken the formation of air core vortex, in the light of this study. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Engineering Technology is the property of Editorial Department of Electric Power Engineering Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transport time lag is a crucial characteristic of fire spreading in fire early stage, which determines the activation time of the fire detector. To clarify the quantitative relationship between the delay behavior and the quasi-steady state of smoke transmission in a long-narrow space, a time-varying spreadsheet is theoretically proposed to calculate the delay time of fire smoke transmission based on the theory of weak plume and the existing achievements concerned. Moreover, a theoretical model concerning the critical time for quasi-steady state assumption applicability is developed, where the method of calculating the critical time is also presented. The results of the case study show that due to the difference of smoke spreading velocity in long-narrow spaces and unconfined spaces for a case with the same conditions, the critical time for the smoke transmission to reach the quasi-steady state at a given radial distance on the ceiling in a long-narrow space is larger than that in the open space. For the open case, the thin ceiling plume, the small volume of entrained air, and the relatively high velocity of smoke lead to the longer delay time of smoke transmission in a long-narrow space than that in the open space under the same situations.

[Display omitted] • Kinetics and rheology were both studied for hydrate formation with KHIs' presence. • The concept of 'critical time' was proposed to distinguish hydrate formation stages. • Hydrate kinetics and rheology has various sensitivity to determine the critical time. • One new KHI was proposed which has good inhibition performance on hydrate. Kinetic hydrate inhibitors have the characteristics of delaying hydrate nucleation and reducing hydrate growth rate. The utilized of kinetic hydrate inhibitors for hydrate blockage risk management is a promising technology for hydrate prevention in oil and gas industry. In this study, the rheological and kinetic properties of gas–water systems contained pure water, polyvinyl pyrrolidone and newly-synthesized inhibitor during hydrate formation at different subcooling degrees were in situ characterized using a high-pressure rheometer. By analyzing the experimental results, the concept of 'critical time' have been proposed to divide the time-varying process of hydrate formation into multiple stages. The three critical times indicated distinct trends in viscosity and pressure changes, as well as varying risks of hydrate blockage in hydrate prevention. The results further compared the differences in determining critical time through pressure and viscosity. The critical time of hydrate nucleation determined by viscosity was earlier than pressure due to the hypothesis of lag in gas consumption. The critical time of rapid hydrate growth determined by viscosity was later than gas consumption, which may be due to that the sharp increase in viscosity requires the aggregation of hydrates. According to the inhibition effect evaluation results determined by three critical times, it was found that the newly-synthesized inhibitor was more effective than polyvinyl pyrrolidone in inhibiting nucleation, delaying rapid hydrate growth time and reaching high viscosity time. This study can provide a comprehensive evaluation method for assessing the performance of kinetic hydrate inhibitors from both kinetic and rheological perspectives. [ABSTRACT FROM AUTHOR]

The monkeypox virus (MPXV) has caused an unusual epidemiological scenario—an epidemic within a pandemic (COVID-19). Despite the inherent evolutionary and adaptive capacity of poxviruses, one of the potential triggers for the emergence of this epidemic was the change in the status of orthopoxvirus vaccination and eradication programs. This epidemic outbreak of HMPX spread worldwide, with a notable frequency in Europe, North America, and South America. Due to these particularities, the objective of the present study was to assess and compare cases of HMPX in these geographical regions through logistic and Gompertz mathematical modeling over one year since its inception. We estimated the highest contagion rates (people per day) of 690, 230, 278, and 206 for the world, Europe, North America, and South America, respectively, in the logistic model. The equivalent values for the Gompertz model were 696, 268, 308, and 202 for the highest contagion rates. The Kruskal–Wallis Test indicated different means among the geographical regions affected by HMPX regarding case velocity, and the Wilcoxon pairwise test indicated the absence of significant differences between the case velocity means between Europe and South America. The coefficient of determination (R2) values in the logistic model varied from 0.8720 to 0.9023, and in the Gompertz model, they ranged from 0.9881 to 0.9988, indicating a better fit to the actual data when using the Gompertz model. The estimated basic reproduction numbers (R0) were more consistent in the logistic model, varying from 1.71 to 1.94 in the graphical method and from 1.75 to 1.95 in the analytical method. The comparative assessment of these mathematical modeling approaches permitted the establishment of the Gompertz model as the better-fitting model for the data and the logistic model for the R0. However, both models successfully represented the actual HMPX case data. The present study estimated relevant epidemiological data to understand better the geographic similarities and differences in the dynamics of HMPX.

In the liquid hydrogen storage and delivery, cavitation and boiling bubbles are prone to occur, which reduces the safety and economy of the liquid hydrogen delivery. For the bubble in liquid hydrogen, its growth process is different from that of room temperature media owing to the thermodynamic properties. In this paper, a single bubble growth model in liquid hydrogen is developed considering temperature distribution inside the bubble. The growth of single bubble in liquid hydrogen is described and predicted by solving Rayleigh-Plesset equation, thermal diffusion equation, thermal equilibrium equation, and heat conduction equation in semi-infinite space simultaneously. The growth trend of bubble radius, radius growth rate, vapor pressure, thermal boundary layer thickness and temperature difference between boundary and center are investigated by the model. The influence of superheat and ambient pressure on the growth of single bubble in liquid hydrogen is investigated by analysis of variance (ANOVA) and range analysis method. The mechanism of the single bubble transform from dynamic growth to thermal growth is clarified by comparing the critical time of the above physical indicators. • A cryogenic cavitation model is developed considering temperature at bubble center. • The growth of single bubble in liquid hydrogen is described and predicted. • Influence of factors on critical times of bubble growth is investigated. • The relationship among critical times of bubble growth is drawn by statistics. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Halide perovskite light‐emitting diodes (PLEDs) have raised considerable attention due to their high color purity and rapid development performance. Although high‐efficiency PLEDs have been continuously and repeatedly reported, the lack of a highly reproducible manufacturing process for PLEDs hinders their future development and commercialization. Here, a generic protocol for rational control of the nucleation and crystallization process of the perovskite emission layer is reported. Through the monitoring of the photoluminescence during spin‐coating, the antisolvent dripping time can be precisely determined. Therefore, it is possible to repeatedly produce a perovskite emission layer with high PLQY, smooth surface/interface, and good homogeneity. As a result, high‐performance PLEDs are easily obtained. Moreover, the standard deviation of the fabricated PLEDs performance is smaller than 0.8%, showing high reproducibility independent of the process conditions such as the process temperature, solvent atmosphere, and spin‐coating parameters, which highlights the statement of the importance of rationally control of the antisolvent process. The methodology provides important progress towards highly reproducible manufacturing of PLEDs for practical applications. [ABSTRACT FROM AUTHOR]

Under mixed traffic conditions prevailing on Indian roads, drivers show complex response when faced with yellow signal because lane assignment gets dynamic in nature. The present study analyzes the effect of surrounding vehicles on response of the drivers while facing dilemma at intersections. Although dilemma zone definitions hold true in case of homogeneous traffic mix, a statistical analysis is performed to check the consistency across the definitions under mixed traffic condition. Present study shows a significant difference in percentage of red light running in comparison to homogeneous traffic as reported by various studies. For carrying out the research, study locations are chosen in such a way to reflect diversity in road geometry, traffic composition and signal characteristics. The results deduced in this study indicate a strong correlation between the driver's decision making choice and the effect of presence of surrounding vehicle at the onset of yellow signal. The effect of critical time analysis has been found out to be one of the parameters other than critical distance in categorizing driver's aggressiveness while facing the yellow signal. In the process of identifying the statistical significance of dilemma zone definitions, it has been found that under heterogeneous traffic condition, drivers behave differently as compared to homogenous traffic when it comes to dilemma zone. It is observed that the percentage of vehicles crossing the intersection when faced with dilemma by violating the red light is 11.6% according to dilemma zone definition I whereas the definition II has yielded about 10.8% violation covering different vehicle types. The above violation figures derived based on the above definition is somewhat higher as compared to homogeneous traffic condition which is observed to be of the order of 5%–6%.

The existing geogrid constitutive model does not consider its damage effects under high stress. To analyze the mechanical properties (creep and stress relaxation) of geogrids under arbitrary loading history conditions while considering the different creep characteristics of geogrids under different load levels, it is considered that the geogrid exhibits elastic strain, plastic strain, and viscoelastic strain when it is at a low stress level, and a viscoelastic-plastic model that can reflect the attenuation creep under low stress level is established. Furthermore, when the geogrid is at a high stress level, in addition to the strain at a low stress level, the damage effects of the geogrid needs to be considered, and a viscoelastic-plastic damage model reflecting the non-attenuation creep under high stress levels is established. Both models are composed of spring, plastic element, and Kelvin body in series. The research results show that the two constitutive relations of the proposed geogrid can better match the test results under different stress levels and can predict the stress relaxation of the geogrid well. According to the creep curve fitting of the geogrid, the relationship between the critical time and stress change considering the damage of the geogrid can be obtained, and then the stress range that needs to be considered for the damage of the geogrid can be determined; the stress–strain relationship of the plastic element changes in the form of a hyperbola passing through the origin. These results can provide a scientific basis for studying the performance of geogrids under long-term loads and analyzing their creep reduction coefficients. [ABSTRACT FROM AUTHOR]

Background: Maternal handwashing practice is an important measure to prevent the spreading of childhood disease. Handwashing is still being practiced to a very low extent especially at critical times since the global prevalence of handwashing with soap was estimated at 19% by a systematic review after compiling 42 studies all over the world. Objective: To assess the handwashing practice and its predictors among mothers of children aged 0 to 23 months in Mareka District, south Ethiopia, 2020. Method: A community-based cross-sectional study was conducted with a multistage sampling technique on 520 women having children aged 0 to 23 months in Mareka District. Data were collected by using interviewer-administered pre-tested structured questionnaires. Data were checked for completeness and entered into Epi data entry 4.6.2. The data were exported into SPSS version 22 for analysis with multivariate logistic regression analysis at P <.05. Result: Mothers wash their hands with soap and water after visiting the latrine (27.1%), after cleaning the child's bottom (28.5%), before cooking (6.2%), before eating (6.9%), and before feeding the child (21.2%). The most important predictors were water availability near the handwashing location with an adjusted odds ratio (AOR) 5.26 (95% CI 1.99-13.69) and soap availability near the handwashing location with AOR 0.40 (95% CI 0.18-0.89) for good handwashing practice. Conclusion: The handwashing practice at critical times was low. The presences of water and soap near the handwashing location were the most important predictors. It is necessary to increase the provision of both water and soap near the handwashing location for improving handwashing with soap and water at key times. [ABSTRACT FROM AUTHOR]

Estimation of temporal changes undergone by municipal solid waste (MSW) in its physico–chemico–geomechanical properties in a bioreactor landfill (BLF) is essential for: (i) efficient landfilling, (ii) establishing the state of decomposition of MSW with time and (iii) deciding upon the appropriate time to initiate landfill mining. To achieve this, a series of destructive (DTs) and non-destructive tests (NDTs) can be conducted on the MSW samples in the BLF. With this in view, several DTs were conducted on these samples retrieved from different depths of the two cells of a fully operational BLF in Mumbai, India. Subsequently, the physical and chemical properties of these samples such as composition, moisture content, volatile solids (VS), elemental content, lignocellulosic content (i.e. cellulose, hemicellulose and lignin content) and bio-methanation potential, were determined by following the laboratory testing, as a function of time. Also, NDTs such as cone penetration test and multichannel analysis of surface waves were conducted on these cells of BLF to obtain geomechanical parameters (viz. cone resistance, sleeve resistance, friction ratio and shear wave velocity) of the MSW. Based on the data obtained from these tests, and reported in the literature, it has been observed that the VS, elemental content, lignocellulosic content and bio-methanation potential of MSW exhibits very well-defined trends, as compared to the geomechanical parameters, with time. Furthermore, it has been observed that the VS, hydrogen-, carbon- and nitrogen-content reduce significantly (≈62%, 70%, 50% and 30%, respectively), following an exponential decay, until the critical time (t cr) (≈4 years) has been achieved. As, beyond t cr these parameters remain practically unchanged, which corresponds to the 'stabilized MSW', mining of the BLF can be initiated without further delay. [ABSTRACT FROM AUTHOR]

In this study, we investigated the sludge rising process during denitrification, especially its hydrodynamics, with both experiments and computational fluid dynamics (CFD) modeling. The rising process was observed and divided into three stages: bubble-forming, sludge particles rising with isolated bubbles, and sludge blanket rising. A new solid phase denoted as lighter sludge was introduced in the CFD simulation to bridge the gap between the simulation and the reality. We simulated the three-phase (wastewater, normal activated sludge, and lighter sludge) turbulent flow in the secondary clarifier. CFD simulation agreed with the experiments and math-model results. Lighter sludge dominated the effluent quality during the denitrification process. Sludge blanket rising started at scattered points in the bottom hopper. A 30-min window occurred between the rising of the sludge blanket and the worsening of effluent quality, which could be regarded as a critical time to prevent sludge from rising. [ABSTRACT FROM AUTHOR]

The Fisher–Kolmogorov–Petrovsky–Piskunov (Fisher–KPP) equation is one of the prototypical reaction–diffusion equations and is encountered in many areas, primarily in population dynamics. An important consideration for the phenomena modelled by diffusion equations is the length of the diffusive process. In this paper, three definitions of the critical time are given, and bounds are obtained by a careful construction of the upper and lower solutions. The comparison functions satisfy the nonlinear, but linearizable, partial differential equations of Fisher–KPP type. Results of the numerical simulations are displayed. Extensions to some classes of reaction–diffusion systems and an application to a spatially heterogeneous harvesting model are also presented. [ABSTRACT FROM AUTHOR]

Now a days most of the techniques are working on critical time data processiong, cloud computing is one of the most popular soft computing techniques, is hard to implement because it need higher latency and bandwidth. To rectify this problem edge computing is used. Edge computing isthe prototype or methodology of critical time data processing which processes data at network edge. Edge computing's main work is that it reduces the location gap in between the storage where data is stored and the computation location. As the name suggest its an time critical application so used where time is crucial. In this paper we propose a model to create edge computing device by using linux platform. It is basically application which is used in latest model car which have facility of on board and gps sensor. Multiple data segments has been collected and analysed by Edgex which supports to implement IoT applications. This research shows that edge computing can improve IoT applications performance. [ABSTRACT FROM AUTHOR]

Abstract Background The burden of communicable diseases within developing countries is mainly influenced by poor personal hygiene practices. Hand washing is considered as most cost effective intervention for reducing health problems such as diarrhoea and acute respiratory tract infections. This study aimed to assess hand washing practice at critical times and identify associated factors among mothers of under five children in Debark town. Method A community based cross-sectional study design was carried out from May 1–20, 2018 in Debark town. After selection of participants using simple random sampling, face to face interview was performed by using semi-structured pre-tested questionnaire. Data were entered into EPI Info 7 and exported into SPSS 21 for further analysis. Results were presented by simple frequency, percentage and mean for descriptive variables. Binary logistic regression analysis was used to test the association of dependent and independent factors. Variables with 95% confidence interval and p ≤ 0.2 during the univariable binary logistic regression analysis were included in the multivariate logistic regression analysis. At the final model variables with p ≤ 0.05 were treated as significantly associated factors of hand washing practice at critical times. Results Good hand washing practice at critical times was reported in 52.2% (95% CI: 47.5, 57.2%) of study participants. Desirable attitude [AOR = 3.37, 95% CI (2.03, 5.58)], presence of water for washing hands [AOR = 4.86, 95% CI (1.26, 18.69)] and a good knowledge [AOR = 2.98, 95% CI (1.92, 4.60)] were significantly associated factors with hand washing practice at critical times. Conclusion The hand washing practice at critical times of study participants was found to be low. A significant proportion of mothers of under five children have a poor hand washing practice at critical times. It is necessary to increase the access to water and to improve knowledge and attitude of mothers to improve their hand washing practice at critical times.

Stroke survivors are at high risk of falling during turning. The kinematics of performing a 360° turn have not been fully analyzed among individuals after stroke. Quantitative differences in the parameters of turning between healthy older adults and those after stroke could provide detailed information on turning ability among these groups. The purpose of the current study was to characterize differences between healthy older adults and adults after stroke in 360° turn kinematics. Fourteen individuals with chronic stroke (mean age: 69 ± 8.4 years) and 14 healthy older adults (mean age: 74 ± 8.7 years) performed three trials of 360° turning. Kinematics data were collected using 26 reflective markers at several body landmarks. This new method for quantifying turning revealed that stroke significantly affected the number of turn cycles, number of single support (SS) critical phases, and critical time. In some cases, falls among individuals with stroke may be related to the combination of impaired movement patterns and the complexity of tasks such as turning. Understanding turning kinematics can inform clinical interventions targeting improvements in turning ability and consequently, fall risk reduction in individuals after stroke. [ABSTRACT FROM AUTHOR]

SynopsisBoth optimal stereoacuity and integration time to achieve that are impaired in patients with intermittent exotropia. The deterioration of stereoacuity is more revealing since it correlates well with exotropia control score.BackgroundDespite the periodic misalignment of two eyes, some intermittent exotropia (IXT) patients exhibit normal stereoacuity, particularly when evaluated with static tests. It is not clear if the temporal integration process of stereopsis is altered in IXT patients, thus warranting further research.MethodsIXT patients (n = 29) and age-matched normal controls (n = 36) were recruited. Static stereopsis was measured with the Titmus stereoacuity test. In computer-generated random dots tests, stereoacuity was measured with a stimuli presentation duration varying from 100 to 1,200 ms. And the relationship between stereoacuity and stimuli duration was fitted into a quadratic model. Optimal stereoacuity was achieved when fitted curve flattened and the critical integration time was the duration needed to achieve optimal stereoacuity.ResultsIXT patients were not found to differ significantly from control subjects under the Titmus test, while the Random Dots stereotest showed significantly worse optimal stereoacuity and significantly longer critical integration time. Multiple regression analysis showed that age (R = −4.83; P = 0.04) had statistically significant negative correlation on the critical integration time, age (R = −6.45; P = 0.047) and exotropia control scores (R = 60.71; P = 0.007) had statistically significant effects on optimal stereoacuity.ConclusionThe temporal integration for stereopsis is impaired in IXT patients, requiring longer critical integration time to achieve elevated optimal stereoacuity.

This article presents a method for timetabling a project affected by risk. The times required to carry out tasks are modelled using type-2 fuzzy numbers. The parameters of these type-2 fuzzy numbers are given by experts: the lower membership function corresponding to the duration of a task in stable conditions, with no risks materialising, and the upper membership function corresponding to the duration of a task in the case when risks do occur. Finally, a case study will be presented and analysed: the project of constructing a shopping mall in Poland. [ABSTRACT FROM AUTHOR]

The determination of the transient stability of an electric power system is a crucial step in power system analysis. This paper investigates the transient stability of an IEEE-9 bus system consisting of three generators and nine buses. At first, a load flow analysis is conducted in order to determine the pre-fault conditions. Secondly, fault analysis is performed to analyze post fault conditions like the fast fault clearing time and load switching in order to determine the system stability. For transient stability analysis, Euler and Runga methods are compared and applied on the frequency and rotor angle of the system to analyze the system variations under different fault conditions. The simulations were done on the Power World Simulator (PWS) software. It is concluded that Critical Fault Clearing Time (CFCT) is a very important factor in keeping the power system within the stability bounds. A slight increase in Clearing Time (CT) from the critical value causes un-synchronism. [ABSTRACT FROM AUTHOR]

UV Raman, TG-MS (TPO) and nitrogen physisorption characterization were used to characterize deactivated Mo/HZSM-5 catalysts from coupling reaction of methane CO2 autothermal reforming (MCAR) and methane dehydroaromatization (MDA). The results show that MCAR/MDA maintains the Mo-oxo species throughout the process, reducing the maximum C6H6 yield, but extending the reaction life by at least 4 time. As O/CH4 increases, MCAR/MDA changes from oxygen-deficient to oxygen-rich state. For MCAR/MDA under oxygen-deficient condition, O2 can only delay the accumulation of aromatics. Grown of coke on Brӧnsted acid eventually leads to complete blockage of the micropores of the catalyst. Slowly deposited graphite coke in MCAR/MDA extended the critical time by nearly 4 times. For MCAR/MDA under oxygen-rich condition, a 70% C6H6 selectivity was maintained throughout the process. After 3700 min of operation, the remaining micropore volume and micropore surface of the deactivated catalyst remained above 1/3. The timely removal of graphite coke at the pore mouth by the MCAR/MDA reaction under oxygen-rich conditions can eliminate the limitation of C6H6 diffusion, thereby effectively preventing the acceleration of the coke deposit micropores which cause the MDA reaction to be rapidly deactivated. [ABSTRACT FROM AUTHOR]

Synopsis: Both optimal stereoacuity and integration time to achieve that are impaired in patients with intermittent exotropia. The deterioration of stereoacuity is more revealing since it correlates well with exotropia control score. Background: Despite the periodic misalignment of two eyes, some intermittent exotropia (IXT) patients exhibit normal stereoacuity, particularly when evaluated with static tests. It is not clear if the temporal integration process of stereopsis is altered in IXT patients, thus warranting further research. Methods: IXT patients (n = 29) and age-matched normal controls (n = 36) were recruited. Static stereopsis was measured with the Titmus stereoacuity test. In computer-generated random dots tests, stereoacuity was measured with a stimuli presentation duration varying from 100 to 1,200 ms. And the relationship between stereoacuity and stimuli duration was fitted into a quadratic model. Optimal stereoacuity was achieved when fitted curve flattened and the critical integration time was the duration needed to achieve optimal stereoacuity. Results: IXT patients were not found to differ significantly from control subjects under the Titmus test, while the Random Dots stereotest showed significantly worse optimal stereoacuity and significantly longer critical integration time. Multiple regression analysis showed that age (R = −4.83; P = 0.04) had statistically significant negative correlation on the critical integration time, age (R = −6.45; P = 0.047) and exotropia control scores (R = 60.71; P = 0.007) had statistically significant effects on optimal stereoacuity. Conclusion: The temporal integration for stereopsis is impaired in IXT patients, requiring longer critical integration time to achieve elevated optimal stereoacuity. [ABSTRACT FROM AUTHOR]

Stroke survivors are at high risk of falling during turning. The kinematics of performing a 360° turn have not been fully analyzed among individuals after stroke. Quantitative differences in the parameters of turning between healthy older adults and those after stroke could provide detailed information on turning ability among these groups. The purpose of the current study was to characterize differences between healthy older adults and adults after stroke in 360° turn kinematics. Fourteen individuals with chronic stroke (mean age: 69 ± 8.4 years) and 14 healthy older adults (mean age: 74 ± 8.7 years) performed three trials of 360° turning. Kinematics data were collected using 26 reflective markers at several body landmarks. This new method for quantifying turning revealed that stroke significantly affected the number of turn cycles, number of single support (SS) critical phases, and critical time. In some cases, falls among individuals with stroke may be related to the combination of impaired movement patterns and the complexity of tasks such as turning. Understanding turning kinematics can inform clinical interventions targeting improvements in turning ability and consequently, fall risk reduction in individuals after stroke.

Air bubble is a manufacturing defect that is common to composite wind turbine blades, which might evolve into cracks, leading to failure under load. The evolution and critical state of air bubble are studied to establish a condition assessment method for blade quality control. A method that is based on rheological theory is proposed to recognize the critical state by temperature jump. The air bubble is regarded as a null set and the temperature distribution of bubble defect is affected by the volumetric strain energy under tensile load. An infrared camera can detect a temperature jump when mechanical characteristics drastically change due to crack formation. A tensile fatigue test was carried out to verify the accuracy of this method. The relative error between the measured and calculated temperature rise at the critical moment was less than 7%. Additionally, the specimen with [0/90]s ply angles is more favorable to maintain the structural stability than the others. The method in this paper establishes a quantitative relationship between the meso-defect and macro mechanical properties. The defect severity of wind turbine blade can be defined by infrared imaging technology. [ABSTRACT FROM AUTHOR]

Over the years, one of the key areas of interest in power system is to achieve the adequate conditions needed for stability. Load changes, generator outages, line outages, faults and voltage collapses are some of the disturbances that affects the stable power system operation by dissipating energy. The amount of dissipation of transient energy is frequently used as a device to measure dynamic system restraining. This paper relates and discourses the control approach for suppressing unwanted electromechanical fluctuations in the power system with a STATCOM, a Voltage Source Converter (VSC) capable of generating or absorbing independently controllable reactive power at its terminal and TCSC is a device that is added in series to compensate the reactive losses in the transmission line. A SMIB power system was considered over a several disturbances. The results obtained, through MATLAB simulation, show the efficiency and strength of these devices in power system stability. [ABSTRACT FROM AUTHOR]

In the present paper, the microbuckling or internal stability loss in the viscoelastic composites containing unidirected fibers under compression along the fibers is studied by use of piecewise homogeneous body model. In this model, it is used the 3-D geometrically non-linear exact equations of viscoelasticity theory. The composite material was considered as an infinite viscoelastic body with a row unidirected periodically located elastic fibers that have an initial infinitesimal imperfection. When the initial imperfection starts to increase and becomes indefinitely, this is taken as a stability loss criterion and co-phase microbuckling mode out of plane are taken into account. The numerical results about the influence of the interaction between the fibers on the values of the critical time are obtained and presented. [ABSTRACT FROM AUTHOR]

The decommissioning of conventional power plants and the installation of inverter-based renewable energy technologies decrease the overall power system inertia, increasing the rate of change of frequency of a system (RoCoF). These expected high values of RoCoF shorten the time response needed before load shedding or generation curtailment takes place. In a future scenario where renewables are predominant in power systems, the ability of synchronous machines to meet such conditions is uncertain in terms of capacity and time response. The implementation of fast power reserve and synthetic inertia from inverter-based sources was assessed through the simulation of two scenarios with different grid sizes and primary reserve responses. As main results it was obtained that the full activation time for a fast power reserve with penetration above 80% of inverter-based generation would need to be 100 ms or less for imbalances up to 40%, regardless of the synchronous response and grid size, meaning that the current frequency measurement techniques and the time for fast power reserve deployment would not ensure system stability under high unbalanced conditions. At less-unbalanced conditions, the grid in the European scale was found to become critical with imbalances starting at 3% and a non-synchronous share of 60%.

This document develops a transient stability and a small-signal analysis of a multi-machine system. Hence, the analysis uses the data proposed by El-Abiad and K. Nagappan, and the results from the transient stability study obtaned by Lyapunov's second method; these studies were compared to the answers obtained from the DigSILENT PowerFactory 15.1 system. Therefore, the "RMS/EMS Simulation" funtion is implemented, allowing to define the t-d curves, the speed profiles, the voltage and the frequency. In addition, the small-signal study is included with the "Modal Analysis" function that allows the visualization of the system responses to the smallest disruptions throughout the root locus analysis. Finally, this analysis allows to get a wider view to the stability problems stablished for robust systems that must support failures during the operation. Likewise, new techniques could be implemented to coordinate protections. [ABSTRACT FROM AUTHOR]

The sedimentation process of granular materials exists ubiquitously in nature and many fields which involve the solid-liquid separation. This paper employs the coupled computational fluid dynamics and discrete element method (CFD-DEM) to investigate the sedimentation process of non-cohesive particles, including the hindered settling stage and the deposition stage. Firstly, the coupled CFD-DEM model for sedimentation is validated by the hindered settling velocity at different solid volume concentrations of suspension $$\phi _{0} $$ , i.e., $$\phi _0 =$$ 0.05-0.6. Two typical modes of sedimentation are also presented by the concentration profiles and the equal-concentration lines. Then, the comparisons between mono- and poly-dispersed particle system are detailed. In the sedimentation of the poly-dispersed particle system, the segregation phenomenon is simulated. Furthermore, this segregation effect reduces with the increase of the initial solid concentration of suspension. From the simulations, the contact force between every pair of particles can be obtained, hence we demonstrate the 'effective stress principle' from the view of the particle contact force by giving the correspondence between the particle contact force and the 'effective stress', which is a critical concept of soil mechanics. Moreover, the deposition stage can be simulated by CFD-DEM method, therefore the solid concentrations of sediment bed $$\phi _{\mathrm{max}} $$ on different conditions are studied. Based on the simulation results of $$\phi _{\mathrm{max}} $$ and the theory of sedimentation, this paper also discusses a method to calculate the critical time when sedimentation ends of two typical modes of sedimentation. [ABSTRACT FROM AUTHOR]