Time Spread Research Articles

Perbandingan Algoritma Regresi Linier dan Regresi Random Forest Dalam Memprediksi Kasus Positif Covid-19

The world is in an uproar by a virus that was first reported in Wuhan, China. This virus is reported to have a very wide spread in a short time, so that it spread throughout the world. The World Health Organization (WHO) has designated Corona Virus Disease 2019 as a global pandemic. In a short time the Covid 19 virus immediately spread to all corners of the world, including Indonesia. As a result of the spread of COVID-19 which soared, there was a stir in the community. This situation affects many sectors of the nation's life. Therefore, the researchers conducted this study to find out how much data were affected, died, and recovered from Covid 19 and how to analyze linear regression and forest random regression. The results of the author's research resulted in an RMSE value of 4310,952 MAPE 19.9 and an accuracy rate of 91.4% in the Linear Regression algorithm while the Random Forest algorithm produced an RMSE value of 4342,481, MAPE 16.2 and an accuracy rate of 91.3%. So it can be said that in this research linear regression is slightly better than random forest.

Nodal is a short-range morphogen with activity that spreads through a relay mechanism in human gastruloids

Morphogens are signaling molecules that convey positional information and dictate cell fates during development. Although ectopic expression in model organisms suggests that morphogen gradients form through diffusion, little is known about how morphogen gradients are created and interpreted during mammalian embryogenesis due to the combined difficulties of measuring endogenous morphogen levels and observing development in utero. Here we take advantage of a human gastruloid model to visualize endogenous Nodal protein in living cells, during specification of germ layers. We show that Nodal is extremely short range so that Nodal protein is limited to the immediate neighborhood of source cells. Nodal activity spreads through a relay mechanism in which Nodal production induces neighboring cells to transcribe Nodal. We further show that the Nodal inhibitor Lefty, while biochemically capable of long-range diffusion, also acts locally to control the timing of Nodal spread and therefore of mesoderm differentiation during patterning. Our study establishes a paradigm for tissue patterning by an activator-inhibitor pair.

Unprecedented Training: Experience of Residents During the COVID-19 Pandemic

Unprecedented Training: Experience of Residents During the COVID-19 Pandemic

Micro and macro-structural properties of waste tyre rubber fibre-reinforced bacterial self-healing mortar

Incorporating waste originated fibre in cementitious mixes facilitate safe waste disposal and leads to environment-friendly construction practices. The use of waste originated fibre sometimes degrades cementitious mixes’ properties due to weak fundamental properties of waste originated fibre. In the present study, waste tyre rubber (WTR) fibre was used to prepare fibre-reinforced self-compacting mortar (SCM) up to 2% volume fraction. To improve the efficacy of WTR fibre-reinforced SCM, calcite precipitating bacteria Escherichia Coli was introduced to the mix by i) direct addition with the mixing water and ii) the use of WTR fibre as bacteria carrier. The effectiveness of two different modes of the bacteria incorporation was evaluated by performing the air content, density, flow spread, and flow time test as fresh state properties. The microstructural characterisation, self-healing ability, compressive strength, flexural strength, indirect tensile strength, porosity, and water absorption tests were conducted as hardened state properties. Results indicated that untreated WTR fibre improved the flow of SCM, whereas bacteria immobilised fibre hindered particle movements of the fresh SCM. Microstructural characterisation revealed loose and non-uniform bacterial calcite precipitation over untreated WTR fibre while incorporating WTR fibre as bacteria carrier showed properly adhered calcite precipitation. Compared to the untreated WTR fiber-reinforced SCM, bacteria immobilised WTR fiber-reinforced SCM exhibited the highest mechanical and durability properties. This study compares two modes of incorporating the bacteria, which indicated that the use of WTR fibre as a bacteria carrier improved the properties of fibre-reinforced SCM.

An improved theoretical model for the maximum smoke temperature rise in a tunnel based on equivalent fire source

The maximum smoke temperature rise underneath tunnel ceiling is of great importance for the assessment of heat exposure, estimation of fire detection time and possibility analysis of fire spread. Previous studies mainly focused on the scenario with a single fire source, but the existence of two fire sources is common due to the increase traffic volume. The maximum smoke temperature rise induced by two fire sources is studied through theoretical analysis in this study. A virtual equivalent fire source is proposed, which is mainly affected by the total fire heat release rate (HRR) of two fires, longitudinal ventilation velocity, effective tunnel height and separating distance between two fires. The HRR of the equivalent fire source decreases with a longer separating distance, which indicates that the influences of the downstream fire on the maximum ceiling temperature weakens gradually as the separating distance increases. An improved model on the maximum ceiling smoke temperature rise caused by two fire sources was developed, and the predictions based on the revised model agree well with the experimental data.

Preparation, characterization and properties study of a superhydrophobic ceramic membrane based on fly ash

With the increasing demand for environmental protection, the recovery and reuse of fly ash has attracted more and more attention. In this paper, the fly ash based porous ceramic membrane is modified from hydrophilic to superhydrophobic successfully. Average contact angle and roll-off angle of the modified superhydrophobic fly ash based ceramic membrane are 151.3° and 11.3°, respectively. Additionally, a variety of performances of the prepared superhydrophobic fly ash based ceramic membrane are characterized. Dynamic process of droplets with different initial velocities impacting on the surface of superhydrophobic fly ash based ceramic membrane is photographed by high-speed camera. It is proved that dynamic process of droplet impacting on superhydrophobic surface includes spreading, retraction and partial rebound. Spreading, retraction and solid-liquid contact time of droplets are about 2.9 ms, 11.5 ms and 14.4 ms, respectively. The above data is almost unaffected by impact velocity of droplets. In addition, experiments show that the prepared superhydrophobic fly ash based ceramic membrane has good acid and alkali corrosion resistance, and self-cleaning performance. In this paper, superhydrophobic ceramic membrane prepared by fly ash shows excellent performance and it can provide guidance for the reuse of fly ash.

Understanding drop spreading behaviour on WC-10wt%Co cutting tools – an experimental and numerical study

WC-Co cutting tools performance under demanding cutting conditions largely depend on the efficiency of the cutting fluid, mainly its ability to remove heat and reduce friction, both highly dependent on the wettability and drop spreading behaviour of the fluid. In this context, this study focuses on the spreading behaviour of machining cutting fluid and water in WC-10 wt%Co cutting tools surface. Contact angles were experimentally measured and then used for performing numerical simulations by the level set method. A contact angle of 75.3˚ and 92.8˚ were measured for the machining cutting fluid and distilled water, respectively, and coincident values were found by numerical simulation, as well as a strong agreement in the drop shape. It was also possible to observe that machining cutting fluid has a lower spreading time than water, due to a lower contact angle and higher viscous dissipation, allowing to reach equilibrium phase sooner. Also, the machining cutting fluid presents a higher drop radius than water, meaning a 24.2% contact area increase over 50 ms of spreading time. Furthermore, numerical simulation showed that the drops spreading over the capillary-inertial time, at the early stage of spreading, follow an exponential dependency with a spreading factor of approximately t1/2, which indicates that the initial spreading of both drops is driven and controlled by the balance between inertial and capillary forces. This work intends to contribute to the knowledge on the phenomena that drive the drop spreading behaviour on WC-10 wt%Co cutting tools, being the development of numerical models to predict this behaviour of utmost importance, since it can lead to the development of novel surface improved tools, with an enhanced lubrification effect and heat removal capacity closer to the cutting zone during machining processes, and consequently allowing an improvement in the tribological and cutting performance of these tools.

Experimental study of liquid droplets impact on powder surface: The application of effective dimensionless parameters in analysis

Spreading dynamics of liquid droplets impacting onto powder bed are experimentally studied using high-speed photography. Dimensionless numbers—We, Re, the modified We* and Re∗ corrected by substrate deformation—are used to analyze the impact behaviors of droplets. The spreading time and the maximum spreading factor are further analyzed. The spreading time is accurately described by a universal scaling law that is obtained from the modified dimensionless time vs. the effective Weber number (We∗), and the maximum spreading factor is found to follow the modified classic scaling law βmax = f(We*, Re*).

Independent and Interactive Effects of Environmental Conditions on Aerosolized Surrogate SARS-CoV-2 — Beijing, China, June to September 2020

What is already known about this topic?Environmental factors such as temperature and humidity play important roles in the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via droplets/aerosols.What is added by this report?Higher relative humidity (61%–80%), longer spreading time (120 min), and greater dispersal distance (1 m) significantly reduced SARS-CoV-2 pseudovirus loads. There was an interaction effect between relative humidity and spreading time.What are the implications for public health practice?The findings contribute to our understanding of the impact of environmental factors on the transmission of SARS-CoV-2 via airborne droplets/aerosols.

Application of heuristics for packing problems to optimise throughput time in fixed position assembly islands

Accompanied with globalisation, companies are confronted with new competitors and price competitions. In order to meet these challenges manufactures strive to increase their efficiency throughout the value stream. Especially special machine manufactures assembling in fixed position assembly islands show a high non-value adding share, since their assembly and logistical processes are characterised by a low degree of standardisation and maturity. This leads to a high spread of throughput times and increases the risk of delivery delays. To improve this weakness, this paper presents an approach to increase the degree of standardisation and to lower and stabilise the throughput time. The new approach bases on heuristics for packing problems and applies them to the material supply. By that, the allocation of the supplied components is optimised, as a result of which search times and path lengths for walking and transporting are shortened and the value adding time share is increased.

Structural, dielectric, and electrical study of bismuth ferrite-lithium vanadate

The composite, BiFeO3-LiVO3 was synthesized through a solid-state reaction technique. The X-ray diffraction (XRD) confirmed the formation of the tetragonal structure at room temperature. The dielectric constant and dielectric loss increased with the rise in temperature. The Nyquist plot projected the contribution of bulk effect and a slight indication of grain boundary effect. The presence of a temperature-dependent relaxation process occurred in the material. Electrical modulus confirmed the non-Debye type relaxation and indicated the asymmetric peak broadening for the spread of relaxation time. The activation energies were calculated from the ac conductivity by linear fitting. The fitted Jonscher power law was very close which implied a similar type of charge carrier which exists in the conduction mechanism for the system. Thermistor parameters were evaluated using the grain resistance for different temperatures.

Pathogen.jl: Infectious Disease Transmission Network Modeling with Julia

We introduce Pathogen.jl for simulation and inference of transmission network individual level models (TN-ILMs) of infectious disease spread in continuous time. TN-ILMs can be used to jointly infer transmission networks, event times, and model parameters within a Bayesian framework via Markov chain Monte Carlo (MCMC). We detail our specific strategies for conducting MCMC for TN-ILMs, and our implementation of these strategies in the Julia package, Pathogen.jl, which leverages key features of the Julia language. We provide an example using Pathogen.jl to simulate an epidemic following a susceptible-infectious-removed (SIR) TN-ILM, and then perform inference using observations that were generated from that epidemic. We also demonstrate the functionality of Pathogen.jl with an application of TN-ILMs to data from a measles outbreak that occurred in Hagelloch, Germany, in 1861 (Pfeilsticker 1863; Oesterle 1992).

Retracted] Research on Maximizing Influence of Blockchain Social Network Based on BCLT Model

In the blockchain social network, the traditional influence maximization algorithm has the problem of insufficient accuracy of the influence spread. To solve the above problem, a BCLT model including the characteristics of the blockchain is established based on the linear threshold model. The BC‐RIS algorithm is proposed based on the reverse reachable set. The BC‐RIS algorithm's influence spread and running time and the traditional algorithm is compared using the real blockchain social network data set. The experimental results show that the BC‐RIS algorithm can obtain a larger influence spread range, which is more in line with the influence propagation law of the blockchain social network.

Beaufort Sea observations of 11 to 12.5 kHz surface pulse reflections near 50 degree grazing angle from summer 2016 to summer 2017.

Sea-surface acoustic scattering is investigated using observations from the 2016-2017 Canada Basin Acoustic Propagation Experiment. The motions of the low-frequency acoustic source and/or receiver moorings were measured using long-baseline acoustic navigation systems in which the signals transmitted once per hour by the mooring instruments triggered high-frequency replies from the bottom-mounted transponders. The moorings recorded these replies, giving the direct path and single-bounce surface-reflected arrivals, which have grazing angles near 50°. The reflected signals are used here to quantify the surface scattering statistics in an opportunistic effort to infer the changing ice characteristics as a function of time and space. Five scattering epochs are identified: (1) open water, (2) initial ice formation, (3) ice solidification, (4) ice thickening, and (5) ice melting. Significant changes in the ice scattering observables are seen using the arrival angle, moment of reflected intensity and its probability density function, and pulse time spread. The largest changes took place during the formation, solidification, and melting. The statistical characteristics across the experimental region are similar, suggesting consistent ice properties. To place the results in some physical context, they are interpreted qualitatively using notions of the partial and fully saturated wave fields, a Kirchhoff-like approximation for the rough surface, and a thin elastic layer reflection coefficient model.

Investigating the Liquid Moisture Transport Behavior of Cotton and Polyester Cotton Blended Woven Fabric

This study focused on the effects of varying the warp and weft densities and blend ratio on the overall liquid transport behavior of plain woven 100% cotton and polyester/cotton blended fabric. Overall Moisture Management Capability (OMMC) and Accumulative One-way Transport Index (AOTI) along with wetting and spreading time of the top and bottom surfaces was measured on moisture management tester. The results were used as a basis to grade the fabric for its moisture transport behavior. It was observed that polyester/cotton blends have an overall higher accumulative one-way transport index and overall moisture management capability than 100% cotton fabric. Furthermore, an increase in the polyester content in the fabric resulted in a significant increase in the transport of moisture. However less number of warp and weft yarns in the blended fabric improved the overall moisture management capability of the fabric.

Molecular dynamics study of nanoscale droplets impacting on textured substrates of variable wettability

The impact of nanodroplets on a solid surface is widely encountered in industrial processes. Understanding the processes that occur when nanodroplets impact a rough surface is of great significance, but the mechanism and dynamics of these processes remain unclear due to the limitations of experimental tools and the shortcomings of most macroscale models. This paper describes molecular dynamics simulations conducted to explore these nanoscale processes. The wettability and solid fraction of the textured substrate and the effects of different impact velocities are investigated. We demonstrate that the maximum spreading time can be described as a power law of the Weber number and that the maximum spreading factor increases with increasing surface wettability. Owing to changes in the attraction between the nanodroplets and the textured substrate, the maximum spreading factor also increases as the solid fraction increases. Based on energy analysis, a theoretical model is proposed for predicting the maximum spreading factor, and this is found to be in good agreement with the simulation results. The results of this study provide useful guidance for predicting the dynamics of nanodroplet impacts.

Women’s Roles and Rights in the Means of Earning and Nation’s Economic Growth

Women are the most important members of the society. Islam is the only religion where women are given their due rights in the light of rights and duties without discrimination. As we know that in human society there have been opinions based on discrimination against women’s character and role. Prophet Mohammad (PBUH) has completed all aspects of prophet-hood and nothing can be added and removed in it. And the most important thing is that Prophet (PBUH) has shed ample light on women’s social and economic role. This elaboration of women’s social and economic role has uncovered the fact that during the time of Prophet Mohammad and spread of Islam women have participated to their utmost to benefit Islam. Among different aspects of women’s liberation one aspect is their right of trade and business ownership which is complete contrast against western concept of women liberation. 
 Though in Islam, women are not obligated to earn for living, but Islam gives them proper right in certain economic issues like, Feminine services, breastfeeding, incubation, and medicine and women surgeries.
 In the light of mentioned example we conclude that women are one of the most important part of economic welfare of the society, and there is no place of Western claim that Islam has made women “a disabled part”.
 In the light of Prophet Mohammad’s (PB UH) character and sayings all possible means of earning for women and their level of participation is discussed and elaborated in accordance with the following professions: trade, agriculture, labor, handicraft. In this brief article following topics will be discussed:
 
 Women’s monetary right in the light of prophet’s Teachings. 
 Legitimate means of earning for women (in accordance with modern era)
 Illegitimate means of earning for women (in accordance with modern era)
 Suggestions and recommendations. 

Sepulchral complexes of human burials and animal deposits, site 23, Sadowie, Opatów Distrct. Study of selected examples

This article attempts to reconstruct the functional relationships between human graves and animal deposits in the context of a Globular Amphora culture cemetery in Sadowie, Opatów District, Sandomierz Upland, Poland. A special characteristic of this cemetery is the grouping of graves into complexes, forming functional-chronological wholes. For the purpose of the study, three such complexes were selected: III (Graves 1 and 2), IV (Graves 5–4-3) and IX (Graves 8–7). Each consisted of a human burial and an accompanying animal deposit of mostly cattle remains. In the case of Complexes III and IX, the lack of stratigraphic relationships and similarity in cultural inventories suggest that they were built at short intervals. Complex IV in contrast, is characterised by a time spread between animal deposits and human burials, which is indicated by radiocarbon dates. The complexes of human graves and animal deposits find analogies in other sepulchral features in the Vistula drainage basin and areas settled by the other regional groups of the Globular Amphora culture at that time.

Optimization of international road transportation of cargoes in the management of enterprises of agricultural sector and road transport enterprises

To enhance the efficiency of management of enterprises in the agricultural sector, it is necessary to improve logistic processes of delivery of livestock and crop production in the implementation of international road transportation. Delivery of cargo "just in time" is very important, so transportation time planning is relevant and allows reducing costs. The process of planning the delivery of perishable goods was described. The spread of the required time is presented for transportation with a varied degree of stochasticity. It was found that the specifics of customs clearance affect the availability of a certain minimum time required for such a procedure. The time of customs clearance of cargo and delay time affect the deadline for cargo registration in international road transportation. The widest spread of time is observed by the procedure of customs clearance of cargoes that takes from 12 to 25 hours, and the probability of customs clearance is only 0.435. Accordingly, this affects a decrease in indicators of "just in time" delivery. The functional dependence of the probability of transit time not exceeding the planned time was compared, depending on the data of the specified route. Based on probabilistic analysis, the possibility of unplanned deviations from the estimated terms of each stage was taken into account and the optimal set of time intervals, which allow obtaining the optimal probability of "just in time" delivery, was proposed. The total cargo delivery time does not change. The recommendations on formulating the requirements for road transport enterprises were given. Namely, to strengthen the requirements for the time of cargo transit. These requirements include the average speed of motion, the choice of appropriate transport, planning the route in terms of the speed mode of highways, etc.

U-Pb zircon age of a sheeted dike complex in ophiolites in the structure of the Revdinsky massif, Ural Рlatinum Belt

Research subject. A tectonic block of ophiolites, corresponding to the root zone of a sheeted dike complex, in the eastern part of the Revdinsky massif of the Platinum-bearing belt of the Urals (UPB).Materials and methods. Zircons for dating were collected in the first-generation dolerite dikes of the sheeted dike complex under study, which had been previously considered as Ordovician. U-Pb dating of zircons was performed by LA-ICP-MS on a NexION 300S quadrupole mass spectrometer with a laser ablation attachment NWR 213.Results. Zircons with an age of 425.6 ± 2.9 Ma are characterized by primary magmatic zoning and apparently correspond to the time of intrusion of the sheeted dike complex. In zircons with an age of 404.0 ± 2.9 Ma, inclusions of metamorphogenic minerals (amphibole, chamosite, quartz, clinozoisite) were discovered. This age reflects rock recrystallization or metamorphism, for example, during the intrusion of later vein rocks of the diorite-tonalite series or dolerite dikes of the second generation. Three points of determination showed a younger age of 362 ± 5.6 Ma, probably reflecting the time of metamorphism at the beginning of collisional processes. Conclusions. For the first time, the Silurian U-Pb age of zircons (LA-ICP-MS) was obtained for the ophiolite block (root zone of the sheeted dike complex) in the structure of the Revdinsky massif UPB. The obtained age of intrusion of the sheeted dike complex (425.6 ± 2.9 Ma) coincides with the age of zircons (428.5 ± 3.7 Ma) from gabbro screens in sheeted dikes of the East Ural zone determined earlier (Smirnov, Ivanov, 2010) and corresponds to the time of spreading over the subduction zone in the Middle Urals.