bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physics virtual laboratory: an innovative media in 21st century learning
Authors: Rani S A , Mundilarto  , Warsono  , Dwandaru W S B 
Published: November 2019

Abstract
Despite Virtual Laboratory (VL) in 21st century Physics learning is commonly used, but its development which is appropriate with theories and concepts is still a lacking. VL is a media to explain abstract concepts and minimize misconceptions. If VL is applied in Physics instruction, a better understanding of Physics theories and concepts is needed. This development study aims to 1) map important components for creating Physics Virtual Laboratory (PVL), 2) create PVL innovation which is appropriate with theories and concepts of Physics, and 3) design the PVL sketch and animation. This study uses an instructional design of Morrison, Ross, and Kemp to create the PVL. Isobaric process in Thermodynamics is provided as the topic. The findings of the study are 1) PVL consists of some components, i.e. basic competence and indicator, video, experiment goals, virtual experiment, and problems, 2) Thermodynamics is applied for developing the PVL, and 3) the final sketch is designed using Corel Draw and Adobe Illustrator, while the animation is created by Adobe Flash. Further study is recommended to implement the PVL to other Thermodynamics processes, such as isothermal, isochoric, or adiabatic.
Review of metal corrosion on food cans
Authors: Rahayu E F , Asmorowati D S 
Published: November 2019

Abstract
Research has been carried out on Fe metal content from samples of tin cans of Lassegakote circulating in the community. This study aims to determine Fe metal content from canned beverage. Sample beverage solution are taken based on the difference in the length of time the sun is exposed. The consentration of Fe is determined by atomic absorption spectrophotometer. The results show that Fe metal content at various type of beverage with tinplate cans is increase if the sunlight exposure is longer.
The fractional separation of citronella, cajeput, and patchouli crude oils using spinning band distillation
Authors: Kurniawan C , Haryani S , Kadarwati S , Cahyono E 
Published: November 2019

Abstract
Spinning band distillation is one of the methods to separate high and close boiling mixtures. Spinning band distillation can be effective as it does not use solvent or other additive for the separation. Fractionation of Citronella, Cajeput, Patchouli essential oils has been experimentally conducted using B/R Instrument Spinning Band Distillation System Model 36-100. The crude oil was placed in the 150 mL heating pot and the temperature cut and heating rate was set. The range of temperature cut is around 230-300, 176-280, and 150-230°C for Patchouli, Citronella, and Cajeput, respectively. Running pressure was set at 10 mmHg for Patcouli oil, and 30 mmHg for citronella and cajeput oil. As expected, the heating process was stable and the solution manages to boil. It is observed that using spinning band distillation, the condensed vapor flow faster than simple vacuum fractionation and at the end product was maximize. The citronella, 1,8-cineole, and patchouli alcohol component were 88%, 67%, 44%, respectively.
Effectiveness of solubility equilibrium module based on lesson study to improve critical thinking ability of chemistry students and teachers in senior high school Kampar district, Riau
Authors: Erna M , Rasmiwetti  , Adnan E , Wahyudi V 
Published: November 2019

Abstract
The study on solubility equilibrium materials based on Lesson Study (LS) have been conducted by chemistry teachers in Kampar District, Riau. This lesson study was involved three main step, namely step plan (planning), do (open class) and reflection. Meanwhile the selected samples in this study were student of Senior High School 1 and chemistry teacher community in Kampar District, Riau. The number of chemistry teacher community and student were involved 6 peoples and 35 peoples, respectively. Research data was analyzed descriptively quantitative. The average score of students’ critical thinking abilities was obtained by 84.21 with very high criterion quality and average score of critical chemistry teacher’s ability on chemical equilibrium material equal to 68 with high criterion. The results of this study indicate that the process of making module discussions and application of solubility equilibrium module can improve the ability of chemical teachers’ thinking effectively.
The determinant of individual smoking consumption in Central Java province
Authors: Subanti S , Hakim A R , Sriwiyanto H S J N , Hakim I M 
Published: November 2019

Abstract
The paper aims to determine the socio-economic factors that significantly affect the individual smoking consumption and to make smoker profile in Central Java Province. This paper uses national economy social survey (Susenas) based on individual analytical units. The estimation technique with ordinary least squares regression. The findings of the paper is the factors that significantly influence the individual smoking consumption are cigarette prices, income, marriage status, urban-rural, education level, poor status, and living condition. This study suggests that to reduce cigarette consumption, the government needs to increase the price of cigarettes. In addition, the government needs to promote anti-smoking campaigns and smoking bans at work.
Representation, representational transformation and spatial reasoning hierarchical in spatial thinking
Authors: Fiantika F R , Setyawati S P 
Published: November 2019

Abstract
The aim of this study is to find out the spatial thinking process of students in transforming 2-dimensional (2D) object image to 3-dimensional (3D) object image representation. Spatial thinking is needed to build how to transforming 2- dimensional (2D) object image to 3- dimensional (3D) object image. There is application of spatial thinking in our daily activities for examples in using maps, planning routes, designing floor plans, and creating art. The students of 5th grade have concrete operation level’s, it is critical period of concrete operation toward early abstract period. In preliminary study researcher found that they have problem to drawing 2-dimensional image object to 3-dimentional image object. They had said that side of cube is not square after they had drawn it but it was parallelogram. It is a problem and important thing, the researcher needs to explore how student using their spatial thinking. It is included how to student thinking process specially in case transforming 3dimensional (3D) object image to 2-dimensional (2D) object image in critical period. Spatial thinking in this study is identified through geometrical problems of transforming a 2dimensional object image into a 3-dimensional object image. Subject in this study are a boy and a girl who have visual learning style in middle level of mathematical ability. This is explorative descriptive study through qualitative approach. The result are: 1) there are different internal representations and spatial reasoning of spatial thinking between a boy and a girl, 2) there are different external representations and spatial reasoning of spatial thinking between a boy and a girl, 3) there are different representational transformation spatial objects between a boy and a girl.
Thin film flow over a bump on an inclined channel
Authors: Wiryanto L H 
Published: November 2019

Abstract
Lubrication theory is applied to model thin film flow on an inclined channel. The flow is uniform, but it is disturbed by a bump so that it produces a surface wave that is formulated into a single equation of the fluid thickness. Since the model is strongly non-linear, a numerical method is chosen for solving the equation. The effect of the bump can be seen by generating the wave at the surface. The wave increases the amplitude, splits, and propagates. For the long run, we obtain a steady form of the surface. The profile depends on the bump.
The estimated proportion of chronic disease sufferer in Duren Sawit district, East Jakarta, using hierarchical bayes method in small area estimation (SAE)
Authors: Fajar I , Siswantining T , Soemartojo S M 
Published: November 2019

AbstractThe purpose of this research is to observe the proportion of chronic disease sufferer in the Duren Sawit district, East Jakarta. The data that used in this research is the primary data in the form of survey data directly and the secondary data in the form of census data from Dinas Kesehatan (Dinkes) 2017 and Badan Pusat Statistik (BPS) 2017. The sampling method used is simple random sampling with a sample size of 1% of the total heads of families living in the Duren Sawit district, that is 1229 the heads of the family. On direct estimation, estimating parameter only based on survey data of subpopulations is inappropriate action, because the sample size obtained relatively few or there are subpopulations that is not selected as the sample. To overcome this, indirect estimation is used with small area estimation (SAE) method, which borrowed extra information such as administrative data or census data from other areas or area itself and there’s an addition random area effect into the model. In this research, the proportion of chronic disease sufferer in Duren Sawit district is obtained used direct estimation and indirect estimation with hierarchical bayes method in SAE. The results of the estimates proportion from direct estimation is 18.87% with Mean Square Error (MSE) is 0.000130741, whereas the estimates of the proportion from indirect estimation is 18.37% with MSE 0.0000922915. Based on the MSE that obtained, the estimate proportion of chronic disease sufferer from indirect estimation is more reliable than direct estimation.
Analysis of obstructive sleep apnea, diabetes mellitus type 2, and prediabetes at dr. Cipto Mangunkusumo hospital using partial least squares
Authors: Puspitaningtyas F E , Siswantining T , Kamelia T 
Published: November 2019

Abstract
This research aims to know the relationship model of OSA, DM type 2, and prediabetes simultaneously. Data used in this research is primary data which obtained by direct examination to patients with OSA at RSCM. The sampling method used in this research is non-probability sampling, with the number of samples is 205 patients. Partial Least Squares (PLS) method is used to obtain the purpose of this research. OSA, DM type 2, and prediabetes are dependent variables. Moreover, the independent variables are gender, age, blood pressure, obesity, and sleep hygiene. The risk of OSA is determined using the Berlin Questionnaire. DM type 2 and prediabetes are determined using fasting blood glucose (FBG). Using significance 0.1, we prove that OSA is directly affected by obesity and sleep hygiene. DM type 2 is directly affected by prediabetes, and indirectly affected by gender, age, obesity, and OSA. Gender, age, and OSA have direct effect to prediabetes, meanwhile, sleep hygiene has indirect effect to prediabetes. While obesity has direct and indirect effect to prediabetes, through OSA.
Stability analysis of a mathematical model of tumor with chemotherapy
Authors: Sari E R , Lestari D , Yulianti E , Subekti R 
Published: November 2019

Abstract
The purposes of this research are to analyze a mathematical model of tumor with chemotherapy and to present numerical verification of the derived result. There are four classes in the model, namely tumor cells, immune cells which is divided by active CTL cells and helper T cells, and chemotherapy drug. There are three kinds equilibrium point: tumor free, tumor persistent, and coexisting equilibrium. The dynamical behaviour of our system by analysing the existence and stability of the system at each equilibrium is discussed. The dynamical behaviour of the model is also numerically verified.
A simulation based teaching method to explain the concept of probability theory; an alternative learning method
Authors: Darnius O , Maulida Y , Enita D B T , Israil S 
Published: November 2019

Abstract
A concept of defining classical probability is often based on the equally likely outcome assumption of an experiment, so the experiment should be based on the equality outcome of media or tool used. If the equality assumption is not met then the alternative for defining probability is done by using the concept of relative frequency. The concept of a relative frequency means that the probability of an event is the proportion of the event occurred in an experiment with infinite trials. Mathematically If P(A) denotes a probability of event A, f(A) denotes the frequency of event A occurred, and n denotes the number of trials in an experiment, then P(A) = lim
n→∞
fA
/
n
, assumed the limit exists. This paper proves the existence of limit for the relative frequency as the number of trials goes infinitely through simulation. This simulation can finally be used as an alternative learning method in understanding the concept of probability.
The process of student’s thinking deduction level to solve the problem of geometry
Authors: Yudianto E , Trapsilasiwi D , Sunardi  , Suharto  , Susanto  , Yulyaningsih  
Published: November 2019

Abstract
Each thinking level van Hiele will describe the process of thinking a people use learning the geometric concepts and types of geometric ideas thinks. This research is a qualitative descriptive research what aims to describe the thinking process of students at the level of deduction in solving geometry problems. The collection data’s method in this research is test and interview method. The test is classification of students’ thinking geometry level according to van Hiele using instruments developed by Usiskin, so that the students get the level of deduction. The test of geometry to knowing the thinking process students use 1 problem from the International Mathematical Olympiad (IMO) field Geometry. Interviews were conducted to the students to confirm the student’s work. The results of this study indicated that students at the level of deduction to solving geometry problems as accordance with the characteristics of van Hiele geomeri thinking in its level.
Analytical and numerical studies of resonant wave run-up on a plane structure
Authors: Andadari G , Magdalena I 
Published: November 2019

Abstract
Wave run-up is the vertical extent of wave up rushed on a structure. To describe wave run-up characteristic, we tend to relate to its maximum height. It was a common belief that the leading wave will usually reach the maximum run-up. However, It turns out that this is not always the case. Resonance is a phenomenon when the incident wave shares the same frequency as the natural frequency. In this article, the natural frequency of a semi-enclosed basin on a plane structure is derived using the variable separation technique. Next, the staggered conservative scheme is used to test these natural frequencies through simulations of wave run up on a plane structure. The result shows that when the incoming wave frequency is close to the natural frequency, the largest run-up height is not the leading wave, but the second, third, or fourth waves. This indicates the occurrence of resonance phenomena. Sensitivity analysis was applied to show the dependence of the maximum run-up height to the structure’s slope, as well as the incident wave frequency. Further, a physical simulation was conducted to examine whether the resonance phenomenon appears in the actual events.
Does motivation have meaning for loyalties? Empirical study from cultural destinations in Bali
Authors: Kencana E N , Darmayanti T , Jayanegara K 
Published: November 2019

Abstract
Over the last two decades, tourism has been successfully proved its significant effect on Bali economic development as well to increase people wealthiest. Since 2010, tourism in Bali contributes more than 35 percent in formulating the regional domestic product. In addition, this sector and its related industries also absorb more than 41 percent of Bali labor force. It is well known that tourism in Bali based on its cultural uniqueness where Uluwatu and Taman Ayun temples are two famous cultural destinations for foreign as well as domestic tourists. This work is directed to elaborate the effect of visitors motivation visited Uluwatu and Taman Ayun temples toward their loyalties. By positioning internal and external motives as the antecedents of tourists’ loyalties and their satisfaction as a mediating construct, the structural equation model (SEM) is built. A hundred visitors of Uluwatu or Taman Ayun were asked to fill out the questionnaire with 5-scaled Likert’s items on August 2017. By applying variance-based SEM, both types of motivations show a significant role in forming visitors’ satisfaction, but only the external motive affect visitors’ loyalties, significantly. Examining the mediating role of visitors’ satisfaction, there is no evidence this construct able to strengthen the effect of internal and/or external tourists’ motives in forming their loyalties.
Analytical solution of the string vibration model on Sasando musical instrument
Authors: Kusumastuti A , Jamhuri M , Hidayati N A 
Published: November 2019

Abstract
This research constructs mathematic model for string vibration on Sasando that expressed as a second-order linear partial differential equation with u denote the vertical displacement experienced by the string at the point x at time t. Besides, the purpose of this research is to determine analytical solution using a method known as separation of variable. There are three analytical solutions from three cases based on constant coefficient values. Case 1 occurs when

k
d

2

>
4

n
π

l

2

1
2

c
2

+
2

c
2

l

. Based on he simulation, the string produces a quarter wave within 3 seconds. This means the vibration wavelength 0.083 Hz. In this case the vertical displacement of the string is back to quiescent after vibrating to produce a quarter wave. Case 2 occurs when

k
d

2

=
4

n
π

l

2

1
2

c
2

+
2

c
2

l

. The string produces 3.5 waves within 3 seconds, means the vibration wavelength is 1.67 Hz. In this case, the farthest vertical displacement (amplitude) become smaller drastically and back to quiescent. Case 3 occurs when

k
d

2

<
4

n
π

l

2

1
2

c
2

+
2

c
2

l

. The vibration wavelength of the string is 2.83 Hz, with 7.5 waves within 3 seconds. The vertical displacement decreases periodically and back to quiescent at a certain time. Analysis of 2-dimensional graph for vertical displacement u(x,t) is done with n = 1,2,3,4,5 which is compared with profile of u(x,t) Gulla (2011). Based on results of the model were mentioned before, the mathematical model of string vibration on Sasando has the similar profile as Gulla (2011). For further, this research is suggested to perform a graph profile analysis of other cases that may arise with variation of parameter values.
Representation of students metacognition in constructing of graphics
Authors: Soedjoko E , Suyitno H , Rochmad  
Published: November 2019

Abstract
The concept of representation is one of the psychological concepts used in mathematics education to explain some important phenomena about how to think. Metacognition knowledge is an indicator of how well a person uses methods and strategies to control and improve their learning and knowledge. The purpose of this study is to describe the representation of students’ metacognition in constructing graphics. This type of research is descriptive qualitative. Research subjects were 6 second semester students at the Department of Mathematics UNNES in 2018. The data collection technique used was a test in the form of constructing a graph. Test results are analyzed by referring to aspects of metacognition, which are revealed through student representation in resolving the problem of constructing a function graph. Based on the results of the analysis, can be grouped into 3 groups; namely Group (1): Students, able to plan problems by understanding the problem and choosing the right strategy, able to monitor the problem through illustrating the picture correctly can then find the results by connecting information obtained from prior knowledge and can relate to other material and be able to evaluate problems indicated by the ability to draw conclusions; Group (2): students have been able to plan the problem correctly but there are still errors in the writing of the settlement procedure, and are able to evaluate the problem through conclusions drawn from the results of the solution, although still not thorough, seen in the absence of units on the results obtained; Group (3): students have not been able to plan problems in writing but can explain the procedure through direct explanation, have not been able to monitor the problem because understanding of the concept is still wrong so it cannot solve the problem and is unable to evaluate the problem correctly.
The development of learning devices based on interpersonal intelligence to improve prospective teachers’ social competence
Authors: Mahmud N , R Amaliyah AR , Amin N , Jufri M , Alimuddin  
Published: November 2019

Abstract
This research is a development research referred to Four-D model. This research aims to develop Interpersonal Intelligence-based of basic statistics learning devices to improve students’ social competence. This type of Four-D model development research consists of four stages: (1) define, (2) design, (3) develop, and (4) disseminate. The learning devices produced are RPS and a textbook that meet valid criteria.
Learning from student thinking in a mathematics classroom
Authors: Tanujaya B , Mumu J 
Published: November 2019

AbstractThe study aims to investigate thinking of students during the mathematics instruction. Data were collected by conducting observations and interviews at 7 secondary schools in Manokwari, West Papua, Indonesia. Observations were held in the classroom and studied videos of instruction to identify what they think during the classroom activities. Data obtained then triangulated through intensive interviews with students, teachers, and pre-service mathematics teachers. The results showed that there are two groups of students, those who have positive and negative thinking. Students who think positively tend to be active, confident and have high motivation. But they tend to be dominant so that it can disrupt the instruction process. On the other hand, students who think contrary tend to be inactive. Students who are inactive are caused by low ability, lack of courage and poor perception of teachers. All groups of students need help from teachers through different teaching strategies.
Identifying students’ understanding of missing angles in parallel lines: a case study of year 7 students in The United Kingdom
Authors: S Salim S 
Published: November 2019

Abstract
This study aims to identify students’ understanding of missing angles in parallel lines by considering what is arbitrary and what is necessary. Data were collected from observing a lesson in a year 7 classroom about the role of angles in parallel lines and interviewing the students to identify their understandings. The results reveal that there are three levels of students’ understanding: (1) the students can remember arbitrary things, but not be aware of the missing angles; (2) the students can remember arbitrary things and sometimes can be aware of necessary things, but get confused when solving a different problem; (3) the students can remember arbitrary things, can be aware of the missing angles although the problem is different from what they usually do, but they do not remember the terms introduced by the teacher during the lesson. It is suggested that teachers have such skill to identify if their students can memorize what is arbitrary and be aware of what is necessary, to assist their students’ memories and to help to educate their awarenesses.