Hasil untuk "cond-mat.mes-hall"

B. A. F. Wehrfritz

Antoine Balikungeri

The acidity constants of 2-morpholinoethanesulfonic acid (MES) have been determined at various ionic strengths; pKa1 = 1.99 and pKa2 = 6.21 at ionic strength I = 0.1 M. The conditional stability constant of CuII-MES complex has been measured by means of a CuII-ion selective electrode: lg cKCu-MES = 1.39 ± 0.07 at pH = 5.57. Furthermore the interaction between CuII and hydrous manganese oxide surface in MES buffer was studied by differential pulse polarography. Conditional stability constants for CuII-MnOx complex (SCu) at three pH values were calculated by two methods: van den Berg-Ružić method as well as the Scatchard plot yield corresponding values for lg cKSCu. Both methods indicated the presence of one class of equivalent binding sites. The results of this investigation corroborate that MES is a suitable buffer for studying metal-MnOx interactions.

Wahyul Huda

", A. Kozhakhmet, Institute of Genetics and Physiology" et al.

Қазақтың етті-жүнді қойы - өнімділігі бойынша елімізде алдыңғы қатарда тұратын қой тұқымына жатады.Бұл зерттеуде төлділікке жауап беретін BMP15 генінің 2 мутациясы қазақтың етті-жүнді бағыттағы қой тұқымында қарастырылады:В2 (c.718C>Т), В4 (c.1100G>T). Зерттеу кезінде 75 қойдың геномдық ДНҚ-сы бөлініп, полимеразды тізбекті реакция (ПТР) арқылы амплификацияланып, рестрикциялық фрагменттердің ұзындығы полиморфизміне (РФҰП) талдау жүргізілді, кездейсоқ таңдалып алынған 10 үлгіге аталған ген бойынша секвенирлеу жүргізілді. ПТР арқылы BMP15 генінің 310 жұп нуклеотидтен (ж.н.) тұратын фрагменті Hinf1 рестрикция ферменті арқылы өңделіп талдау жасалды. РФҰП талдау нәтижесінде Қазақтың етті-жүнді қой тұқымында анықталған мутациялардың мономорфты екендігі байқалды. Келесі ретте BMP15генінің қажетті фрагментіне сиквенс жасалды. Сиквенс нәтижесінде алынған тізбек бойынша NCBI базасындағы қолжетімді әртүрлі қой тұқымдарының ДНҚ сиквенс нәтижелерімен салыстырмалы талдау жасалды. Сонымен қатар, филогенетикалық талдау жүргізілді. Филогенетикалық сызбанұсқа бойынша нақты үш кластер құрылды, зерттеуге алынған үлгілер екінші кластерге біріктірілді. Жалпы сиквенс нәтижелері бойынша зерттеу тобындағы қойларда бірнеше жаңа бірнуклеотидті полиморфизм (SNP) локустары анықталды. Алдағы уақытта жаңадан анықталған SNP маркерлердің қызметтерін анықтау үшін қосымша зерттеулер жүргізілуі қажет.

Debora Exaudi Sirait

Due to the impact of Covid-19, many Indonesians have been affected by layoffs, so they have switched to taking part in the multi-level marketing program of Oriflame and Jafra products, both of which are the best-selling beauty products today. This study examines the marketing strategy used by these two beauty producers using game theory. Game theory is a theory that uses a mathematical approach in formulating situations of competition and conflict between various interests. This theory was developed to analyze the decision-making process, namely the optimum strategy for different competitive situations and involving two or more interests. The problem boundaries were chosen to be 5 aspects of the problem, namely: product, price, location, promotion, and service. From the results of the preliminary questionnaire reliability test using SPSS 19.0 software, a value of 0.820 was obtained. With a pure strategy, a saddle point is obtained because the maximum value is the same as the minimum value, so that the pure strategy is the optimal strategy. Therefore, with a pure strategy, optimal marketing strategies have been obtained from both manufacturers, namely Jafra and Oriflame. Where Jarfa producers use products (variations) as their marketing strategy while Oriflame producers use price as their marketing strategy.

Nurul Qorima Putri, Paian Sianturi

This research is focused on discussing the SEIQRS epidemic model for the spread of the COVID-19 disease with a nonlinear incidence rate. From the result of analysis of the SEIQR model obtained two equilibrium point these are diseases free equilibrium points and endemic equilibrium point. Then, the analysis of the completion behavior is done by using eigenvalues and stability around equilibrium point, the obtained result of the diseases free equilibrium point has two stability traits are saddle point, and stable. The stability diseases free equilibrium will be stable when  R0  1, if R0 1 then the equilibrium point is not stable (saddle point) and conversely the positive endemic equilibrium point will be spiral stable. In numerical analysis, it is done by varying the parameter values and using the fourth order runge-kutta approach.

Rianita Simamora

This study aims to determine the influence of parental attention and learning motivation on mathematics learning outcomes of seventh-grade students of SMP Negeri 1 Pematangsiantar. Parental attention and learning motivation data obtained from an instrument in the form of a closed questionnaire distributed online via google form with good quality because it is valid and reliable. Meanwhile, students' mathematics learning outcomes were obtained from the school's documentation of grades. The test results show that there is a direct effect of parental attention on learning motivation with a t-count of 2.1309 and a significance level of 0.08325; there is a direct effect of parental attention on student mathematics learning outcomes with a t-count of 2.42875 and a significance level of 0.13768; there is an indirect effect of learning motivation on student mathematics learning outcomes with a t-count of 2.58298 and a significance level of 0.14988; there is an indirect effect of parental attention and learning motivation on mathematics learning outcomes. As for the contribution given by parents' attention and learning motivation to mathematics learning outcomes was 28.75% and the total effect was 42.327%. Therefore, the higher parental attention and student motivation, the higher the learning outcomes.

Azrina Purba

Abstract. The purpose of this study is to determine the effect of learning by using a realistic mathematical approach to the ability to understand students' mathematical concepts. This research is a quasi-experimental research. This research was conducted at MTs Islamiyah Medan. The research sample consisted of 50 students, 25 experimental class students, and 25 control class students obtained by cluster random sampling technique in class VII students. The results of the study explained that the average ability to understand mathematical concepts of students who use a realistic mathematical approach is higher than the average ability to understand mathematical concepts of students who use conventional learning. It can be seen from the average posttest score of students' mathematical problem-solving ability of 29.125 in the experimental class and 27.250 in the control class. However, the realistic mathematical approach model in the experimental class was significantly more successful in improving students' understanding of mathematical concept skills compared to conventional methods. Thus the learning of realistic mathematics influences the ability to understand the concepts of mathematical students (tcount = 3.91> ttable = 2.13). The conclusion of this study is that there is a positive influence on realistic mathematical approaches to students' mathematical concept understanding abilities.Keywords: Realistic Mathematics Approach, Understanding of Mathematical Concepts.

Imelda Imelda

Abstract. The purpose of this study was to describe students' difficulties in solving problem solving problems in Algebra and Trigonometry courses. Subjects in this study were students of the Mathematics Education Faculty of Unika Santo Thomas Faculty of Teaching and Education study program in North Sumatra in semester 1 of the 2017-2018 school year, totaling 10 people. The data collection tool used in this study was a test of 5 questions in the form of a description. This type of research is a qualitative descriptive study. Data collection techniques are carried out by tests, observation, interviews and documentation. Data analysis techniques were carried out with the stages of data reduction, data presentation and conclusion drawing. The results showed that students had difficulty using the concept of equality and inequality squared, the use of the concepts of trigonometric formulas. Students also have difficulties in using number sequence principles and completing trigonometric equation solving, difficulties in disclosing information from problem solving and calculation errors. The contributing factor is the existence of several concepts and principles of algebra and trigonometry that are used in solving problems that have not been well controlled by students and are less thorough in performing calculations.Keywords: Analysis of Learning Difficulties, Algebra and Trigonometry

Institute of Computational Technologies MES RK, A. Terehov, N. Makarenko et al.

Automated technology based on ultra-high spatial resolution (QuickBird) satellite data has been developed to estimate fraction of projective covering by crowns of trees and calculate forest integrity on the sample of Aman-Karagaisky forest in the Northern Kazakhstan. The processing algorithm is based on the threshold allocation of mask of shadows and its succeeding morphological filtering. The map of forest’s test area integrity built by Land Cover Classification System [LCCS] criteria have an accuracy of 82.5% relatively to the corresponding map based on an expert decoding.

Phyllis Dalley

František Záviška