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Distance learning activities are a big challenge for teachers because they have never experienced it before. Project-based learning through Google Classroom is an alternative method that can be applied by teachers in distance learning activities (PJJ). The purpose of this study was to determine whether the project-based learning model through Google Classroom could be applied to the learning activities of class IX-9 students of SMP Negeri 8 Pematangsiantar. Project-based learning grammar, namely, first, basic questions, second, designing product plans, third, preparing a manufacturing plan, fourth, monitoring project activities and development, fifth, test results, and sixth, evaluating the learning experience. The results showed that the average student could write the program text correctly. Student performance can be described with an average score of 82 points, the highest score of 95 points, and the lowest score of 70 points. There is 1 person with a score of 95, 3 students with a score of 89, and 7 students with a score of 89. 86, 2 students have 85 points, 6 students have 83 points, 3 students have 79 points, 2 students have 77 points, and 71 students have 7 points. [ABSTRACT FROM AUTHOR]

This research was conducted with the title Analysis of the second semester students' ability of the English Education Study Program in understanding reading texts. The purpose of this research is to examine the students' ability to understand the text. This study uses a qualitative method. The population used is the second semester students of HKBP Nommensen Pematangsiantar University for the 2020/2021 academic year. The sample taken is 32 people. The research data were collected from the given text. During the test, 30 questions were given. The type of test given is an objective test. After collecting the data, the writer then analyzed the students' scores. From these students, it was found that almost all students could not understand the text. There are 19 students (59.37%) who score below 65 and that makes them still need more attention than to help them improve their ability to understand the text. [ABSTRACT FROM AUTHOR]

In order to examine the influence of forcing (river flow and tides) and anthropogenic activities (dredging and dam regulation) on stratification, a study was conducted over a period of 19 months (June 2008-December 2009) in the Gautami-Godavari estuary (G-GE) during spring and neap tide periods covering entire spectrum of discharge over a distance of 36 km from the mouth. The bathymetry of the estuary was recently changed due to dredging of ∼20 km of the estuary from the mouth for transportation of barges. This significantly changed the mean depth and salinity of the estuary from its earlier state. The variations in the distribution of salinity in the Godavari estuary are driven by river discharge during wet period (June-November) and tides during dry period (December-May). The weak stratification was observed during high discharge (July-August) and no discharge (January-June) periods associated with dominant fresh water and marine water respectively. The strong stratification was developed associated with decrease in discharge during moderate discharge period (October-December). Relatively stronger stratification was noticed during neap than spring tides. The 15 psu isohaline was observed to have migrated ∼2-3 km more towards upper estuary during spring than neap tide suggesting more salt enters during former than latter period. Total salt content was inversely correlated with river discharge and higher salt of about 400×10 m psu was observed during spring than neap tide. Flushing times varied between less than a day and more than a month during peak and no discharge periods respectively with lower times during spring than neap tide. The flushing times are controlled by river discharge during high discharge period, tides during dry period and both (river discharge and tides) under moderate discharge period. This study suggests that modification of discharge, either natural due to weak monsoon, or artificial such as dam constructions and re-routing the river flow, may have significant impact on the stratification and biogeochemistry of the Godavari estuary. [ABSTRACT FROM AUTHOR]

The T4 cell count, which is considered one of the markers of disease progression in an HIV infected individual, is modelled in this paper. The World Health Organisation has recently advocated that countries encourage HIV infected individuals to commence antiretroviral treatments once their T4 cell count drops below 350 cells per ml of blood (this threshold was formerly 200 cells per ml of blood). This recommendation is made because when the T4 cell count is low, the T4 cells are unable to mount an effective immune response against antigens and any such foreign matters in the body, and consequently the individual becomes susceptible to opportunistic infections and lymphomas. A stochastic catastrophe model is developed in this paper to obtain the mean, variance and covariance of the uninfected, infected and lysed T4 cells. The amount of toxin produced in an HIV infected person from the time of infection to a later time may also be obtained from the model. Numerical illustrations of the correlation structures between uninfected and infected T4 cells, and between the infected and lysed T4 cells are also presented. [ABSTRACT FROM AUTHOR]

Abstract  We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 �10 6) and high food levels (1.5 � 106 cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter. [ABSTRACT FROM AUTHOR]

This study reports a novel approach for growing multilayer thin films consisting of alternate layers of carbon nanotubes (CNT) and nickel on Si (1 0 0) substrates and justifies their use in thin film temperature sensors. A low pressure chemical vapor deposition system was employed for synthesizing CNT films, while Ni films were deposited by electrodeposition. Porous-Si was used as substrate to increase adhesion between the layers of the multilayer structure. The structure of the multilayer films and the quality of the CNT grown were analyzed using several characterization methods, including scanning electron microscopy, x-ray photoelectron spectroscopy, x-ray auger electron spectroscopy and Raman spectroscopy. The electrical characteristics were investigated using a van der Pauw setup and the effect of the increasing number of CNT layers in the multilayer structure was studied. The sensitivity of the multilayer film was found to increase with increasing number of CNT layers, despite the decrease of the temperature coefficient of resistance. On the other hand, the initial resistance was found to increase. Results indicated that these multilayer structures are appropriate for fabricating highly sensitive thin film gauges that can detect lower heat fluxes with more accuracy. [ABSTRACT FROM AUTHOR]

Background: The automotive parts supply chain measures its success in terms of parts availability and stock required to achieve the availability target, measured as allocation fill rate (AFR). The supply chain strives to achieve an AFR target of 95.5% while maintaining low levels of stock. Objective: The first objective of this study is to evaluate the current inventory management approach, namely the maximum inventory position (MIP) method, to understand the difference between the theoretical derivation and the actual implementation. The second objective is to develop and compare the performance of a new stock target setting (STS) method relative to the MIP methods. Method: The theoretical and actual equations behind the MIP and STS methods are derived for steady state as well as stochastic conditions. A system dynamics simulation model (SDSM) was developed to describe both the local and imported supply chains. The SDSM was used to simulate and confirm the parameters for the STS method. It was also used to compare the three inventory management methods against a theoretical environment and actual data sets. Results: The STS method requires a damping factor (DF) to ensure it does not cause the bullwhip effect. The SDSM was used to determine that a value equal to the lead time ensures effective damping. In the theoretical environment, the MIPTheory method requires the lowest stock, but also has the lowest AFR. MIPActual achieves the highest AFR, but with significantly higher stock holding. The STS method improves on the AFR achieved by the MIPTheory method, with lower stock holding than the MIPActual method. With the actual demand data sets, the results vary by parts movement type. With fast moving parts, all methods achieve the AFR target, the MIPActual method has a higher stock holding for all cases, and the STS method results in reduced stock holding for 7 of 12 cases. With medium moving parts, the MIPActual method improves on the AFR in all 15 cases, but with significantly higher stock. The STS method increases the AFR in 7 of 15 cases and reduces the stockholding in 11 of 15 cases. With slow moving parts, both the MIPActual and STS methods improve the AFR with increased stock holding. The increase in stock holding for the STS method is significantly lower. With erratic moving parts, the MIPActual method improves on the AFR in all 17 cases, but requires significantly higher stock holding. The STS method achieves lower AFR values in 10 of 17 cases, but also requires lower or equal stock holding in 10 of 17 cases. Conclusion: The STS method provides a new approach to inventory management in the automotive supply chain. It provides improved performance for lower stock holding than the implemented MIP method (MIPActual). The results for the different movement category suggest that there is further research to be done to confirm the effectiveness of the various methods with other demand distributions. [ABSTRACT FROM AUTHOR]

Jute plant retting is a preferential rotting process in which jute plants are submerged in water and subsequently jute fibers are extracted out by decomposing the cellular tissues and pectin surrounding the fiber bundles through the joint action of water and aquatic/soil microorganisms. Due to the shortage of water during retting period of jute, all crops cannot be stacked at a time and therefore farmers are often compelled to harvest over-matured plants and use the same water body repeatedly for retting. This generates inferior quality of fiber. Traditional retting is also labor intensive and not environment friendly and takes longer time to ret. A feasibility study has been undertaken for dry retting of jute plants on land under water limiting condition using a defined microbial consortium. Field trials of dry retting of jute plants carried out at farmer's level have shown promising results wherein jute plant retting can be achieved in shorter time without submerging jute plants in water body. Quality of jute fibers obtained from such dry retting process is comparable to the conventionally retted jute process. [ABSTRACT FROM AUTHOR]

Fine size-controlled synthesis of superparamagnetic iron-oxide and its nanocomposites are reported by a supersonic thermal-plasma assisted process. The effects of oxygen flow rates, gas injection position, and carrier gas types were studied, and the phase composition of the product material was estimated by Rietveld refinement technique. The smallest iron-oxide nanoparticle sample with 10 nm average size was synthesized at 19 liters per minute flow of oxygen, which also had the largest contribution from the magnetite/maghemite phases at 88%. The saturation magnetization and the magnetic coercivity of this superparamagnetic sample were measured as 28 emu g−1 and 6 Oe, respectively, the latter one is the smallest value reported in the literature produced by a plasma method. The sample demonstrated satisfactory biocompatibility behavior, which should be suitable for advanced bio-medical and environmental applications. A superparamagnetic nanocomposite material containing iron-oxide, carbon-encapsulated iron nanoparticles, along with single-walled carbon nanotubes was also produced while injecting oxygen into the vacuum chamber and using hydrogen as the carrier gas. The average particle size was 5.1 nm, which had saturation magnetization of 52 emu g−1 and coercivity 10 Oe. The sample was found to be slightly more toxic, assumed due to the presence of the single walled carbon nanotubes. The high rate of production and single step processing were the other important advantages of this synthesis technique for the nanocomposite material. [ABSTRACT FROM AUTHOR]