bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inventory control using ABC and min-max analysis on retail management information system
Authors: Asana I M D P , Radhitya M L , Widiartha K K , Santika P P , Wiguna I K A G 
Published: March 2020

Abstract
Determination of reorder point aims to meet the safety stock. This is a central parameter of inventory control. This study aims to find reorder point based on goods classification and safe stock. This approach is implemented in retail information systems that have been running. The information system has about 15.000 active items with the number of sales transactions around 1.100 per day. The problem in determining the reorder point is the unavailability of the safe stock reference. Lack of safe stock information triggered the ordering goods error. This error causes over stock. It can increase the potential of expired goods. In this study the researcher classifies the goods and determines the amount of safe stock to control the inventory. We used ABC analysis method for goods classification. It divides the group of goods into A, B, C, and D. The amount of safe stock is determined based on the goods sale’s history using Min Max Analysis method. Classification result is used to determine the limits on the inventory of allowed items to be ordered. Limitation safety stock amount refers to the limits from the min max method result. While, testing is done by comparing cost before and after implementation of this method.
Designing a solar power plant model as an energy mix at Darma Persada University
Authors: Suherman E , Astuty E Y 
Published: March 2020

Abstract
Universitas Darma Persada (Unsada) energy profile has an average of almost 2300 kWh everyday. This energy profile is quite high especially at noon, and the existence of solar power plant potential as an electricity producers shows that it is appropriate if Unsada were pushed to utilize this electricity producers as a diffusion of energy supply. Therefor a research is needed especially in power usage data, daily insulation data, solar power plant production specification data from power plant and regulations on the use of renewable energy, electricity to be supplied and power plant system. From the results of processing the data, will be obtained an output of Electricity System and Unsada Electric Energy profile. The solar power plant system that will be develop for the additional power supply is a hybrid solar power system with power plant electrical supply which power is generated at 50.4 kWp. 420 m2 of land is required for the installation of solar panels (can be installed on additional power roofs) and as many as 336 solar panels with 4 locations in each location of 84 solar panels.
Antioxidant activity of loloh Malaka fruit (Phyllanthus emblica L.) in Ayurveda Medication: How it supports environmental conservation
Authors: Cahyaningrum P L , Yuliari S A M , Putra C , Suta I B P 
Published: March 2020

Abstract
Traditional medication method in Bali use the Ayurveda principle known as Usadha. Usadha used herb or fruit as main component of medicine. One of them is Malaka fruit (Phyllanthus emblica L.) and commonly in Bali known as kalimaka, kalimoko, kamlika. Malaka can be processed through boiling using water and consumed as traditional drink (loloh). Malaka fruit has been known to contain vitamin C as antioxidant. Therefore, this research aims to determinant the antioxidant activity of malaka fruit loloh using DPPH (2,2-difenil-1-pikrillhidrazil). The result showed that malaka fruit loloh obtained was antioxidant activity with antioxidant capacity 164 mg/100 mL and IC50 691,1 µg/Ml. Further contains vitamin C obtained was 0,184 mg/100mL, Flavonoid was 3,15 mg/100mL, phenol was 375 mg/100mL and tannin was 546 mg/mL. Based on these result malaka fruit loloh can be use as on alternative for traditional medication.
The role of the informal sector of waste management
Authors: Satori M , Aviasti A , Amaranti R , Shofia N , Utami R P , Faikar F A 
Published: March 2020

Abstract
Garbage, on the one hand, is an environmental problem, but on the other hand, it can give the potential economically. One indication of it there are IS activities that collect certain types of waste as recycled materials and then sold to the recycling industry. This research aims to determine the role of IS of solid waste management (SWM) in Bandung municipality. The study used mixed method research, which is a combination of qualitative and quantitative. The results of this study concluded that the estimated number of scavengers as IS in Bandung municipality is about 3990 people, and contributed to the reduction of waste about 6, 8% of the total solid waste generation. As economically, the average income of IS is IDR 1 million/person/month. Considering the role of IS both in SWM contexts and in economic contexts, the government must be to make a policy to integrate the IS with SWM. Base on the AHP methods, this study recommended that to integrated IS of SWM can be developed by facilitating them at TPS/TPS 3R.The implication of the strategy that the existence of IS will be more organized and reduce waste generation to the maximum.
Soil erosion in agroforestry development in South Bandung Region, Indonesia
Authors: Chofyan I , Andriani D I 
Published: March 2020

Abstract
Forest is an ecosystem unit in the form of a stretch of land containing biological natural resources dominated by trees in its natural environment. Ecologically, the function of forests is to absorb rainwater to prevent erosion. Land conversion of forest to other uses causes disturbed ecological functions of the forest. The agroforestry system is a land optimization system by combining the components of perennial woody crops, agricultural crops and also livestock. Agroforestry systems have become one of the alternative systems to overcome problems that arise due to the high of land conversion. Bandung District recommends 3 types of agricultural crops in the development of agroforestry in the South Bandung Region, namely coffee and tea, which are perennial crops, and vegetable crops which are annual crops. The purpose of this study is to compare the erosion level of the three types of plants used for agroforestry. The method used in this study are land suitability analysis and erosion estimation analysis. The final results of this study conclude that the erosion level of perennial crops is lower than annual crops.
Value of domestic water economy and sustainability of regional cross water resources management
Authors: Burhanudin H , Akliyah L S , Kurniasari N 
Published: March 2020

Abstract
Water resources has economic, political, social and cultural values becomes a commodity desired by many people. On a cross-border administrative scale, the struggle for water can be a problem and is a source of conflict between communities, regions and even countries. A view of water resources as a public commodity that is not subject to prices is time to change especially for water use in a business. Water companies need to take into account the water value in relation to the cost of supply, in order to create sustainable water resources. The principle of paying users is applied to obtain compensation for the benefits received. Costs charged to water users need to be calculated through a reasonable payment mechanism in order to cover the costs of managing water resources that have been spent. The value of water benefits is the basis of the application of economic instruments to help the calculating process of water prices. This paper discusses the case of cross-regional water resource management in Indonesia Kuningan Regency – Cirebon City by emphasizing the value of water benefits as a basis for calculating water prices. Thus this paper will examine how the contribution of water resources if used for domestic water business (drinking water) based on the value of economic benefits and how the implications for the continuity of water resources management. Based on the results of the analysis it has been shown that if the raw water source is used for domestic water business, PDAM in Cirebon City is able to return 75% of the total cost of managing water resources that have been spent. Considering regulations where users of water sources outside the administrative boundaries are required to pay water prices, with this capability, water resources management across the Kuningan Regency -Cirebon City area has the opportunity to continue. On a global scale, the application of economic benefit values as a basis for calculating water prices can be used as a lesson for resolving cases of water resources conflict with characteristics similar to regions in Indonesia. By ensuring sustainable water resource management, at least the completion of cross-regional water resources in Indonesia can reduce the burden to resolve the problem of the water crisis in Southeast Asia.
The monozukuri concept as the right 5S implementation tool in Jakarta Vocational High Schools
Authors: Siahaan F S , Purba J , Buwono A , Ratih R , H Refendi 
Published: March 2020

Abstract
The concept of monozukuri as the implementation of 5S will have an impact on changes in the environment and work procedures towards a better direction. This development can also affect the mindset of ignorance of the environment itself. In general, the dream of every society expects a clean, neat, safe, comfortable environment to be maintained around. In achieving a clean and healthy environment, one of the patterns of approach that will be taken is to apply the 5S lifestyle that will improve the performance of the Vocational High School teachers in Jakarta. How does the monozukuri concept with the implementation of 5 S affect the performance of teachers in Vocational High Schools which aims to create a work environment that is free of obstacles and produces work effectiveness. The work method is carried out starting with creating a questionnaire Likert scale based on 5S implementation variables. Provisions on the judge’s approach to the number of respondents and then the pre-questionnaire test and the results will be tested for validity for the validity of each questionnaire as a parameter of actual data collection. The results of actual data collection will be tested for validity and then analyze the effect of dominant 5S / R by multiple regression methods.
Mathematical creative thinking ability in middle school students’
Authors: Sahliawati M , Nurlaelah E 
Published: March 2020

AbstractThe mathematical creative thinking ability in this study is the ability to think which involves elements of fluency, flexibility, originality, or elaboration, in the process of solving mathematical problems. This study aims at determining the mathematical creative thinking ability of junior high school students in solving the problem of the plane figure. To do so, first, 28 students in the 7th grade (12-13- years-old) from a junior high school in Indonesia were given four plane figure problems. The problems were developed based on indicators of creative thinking ability. Then, three of the students were selected based on the prior mathematical ability to represent the creative thinking ability of all students. The interviews were conducted to confirm the students’ answers. Finally, the results of student answers were analyzed based on indicators of creative thinking ability. The results of the study show that overall students were able to make new problems from the information presented, although the solution they wrote has not been systematically structured. In this case, the most visible students’ creative thinking element is flexibility.
Mathematical reflective thinking strategy in problem-solving viewed by cognitive style
Authors: Salido A , Suryadi D , Dasari D , Muhafidin I 
Published: March 2020

Abstract
Mathematical reflective thinking is a mathematical thinking activity involving the persistent consideration process of the use of knowledge and decision making in solving a problem. This study aims to describe mathematical reflective thinking strategy of students based on impulsive and reflective cognitive styles in solving the mathematical problems. To do so, first, we developed three tasks about the linear programming problems. Next, 35 students of senior high school in the 11th grade (16-17 years-old), were given tasks and continued with the giving one set of Familiar Figures Figure Test (MFFT). Then four students were selected as representatives of the other students. In-depth interviews were conducted with students to confirm the findings of the task’s answers. Finally, the data were analyzed to explain the mathematical reflective thinking strategy of students based on cognitive styles. We found that students with impulsive cognitive styles have a tendency to think reflectively on the stage of understanding and reflection, using inefficient strategies, not completing answers, and give up easily in the face of a difficult task. Whereas the students with reflective cognitive style have a tendency to think reflectively on the stage of reflection and critical reflection, using expert strategies, concluding answers, and solving difficult problems in accordance with logic; and trial and error.
Mathematical connection ability in 7th grade students viewed from self-regulated learning
Authors: Putri E R , Budiyono B , Indriati D 
Published: March 2020

Abstract
The purpose of this research is to determine which mathematical connection ability is better; students with high, medium or low self-regulated learning. This research was descriptive quantitative research. The instruments used in this research were questionnaire of self-regulated learning and written test of mathematical connection ability. The research samples consisted of 186 students who were studying at a state Junior High School in Sukoharjo Regency, Indonesia, with heterogeneous abilities. The data analysis technique used was one-way Anova with unbalanced cell and post hoc test using the Scheffe method. The results show that students with high self-regulated learning have better mathematical connection ability than students with medium and low self-regulated learning. Students with medium self-regulated learning have better mathematical connections ability than students with low self-regulated learning. In order to connect to each mathematical problem, students must first remember the problem, while to understand the problem, students must be able to make connections with topics related to the problem so that students’ efforts in finding solutions to mathematical problems are through self-regulated learning activities. When students have self-regulated learning, they will significantly improve their mathematical connection ability.
Analysis of mathematical creativity in the field of geometry in junior high school students
Authors: Permatasari S D A , Budiyono B , Pratiwi H 
Published: March 2020

Abstract
Nowadays, world civilization has entered the 21st century. One of the challenges of education in the 21st century is the development of human resources that have mathematical creativity. With mathematical creativity, students are trained to solve problems related to mathematics, students can facilitate their abilities, discuss various ways to find solutions, and make combinations of new knowledge or new problem solving techniques. This research has an aim to analyse mathematical creativity in the field of geometry in junior high school students in Surakarta. The research method used in this research is quantitative descriptive. The sample of this research is 56 students from 8th grade student of junior high school in Surakarta were taken by random sampling method that represent the population. The results of this research indicated that out of 56 students of junior high school in Surakarta have 2 students who are on level 3 of mathematical creativity, 17 students who are on level 2 of mathematical creativity, and 37 students who are on level 1 of mathematical creativity. These result can be used as preliminary data to determine the level of mathematical creativity students in Surakarta.
The effect of differentiated instruction on student mathematical communication ability
Authors: Nurasiah L , Priatna B A , Priatna N 
Published: March 2020

AbstractThis study aims to analyze: (a) mathematical communication ability of students before and after learning with Different Instruction; (b) difference between students’ mathematical communication ability using Differentiated Instruction and conventional learning. The research method used in this study is a quantitative research. 70 Junior High School students of the 8th graders, participate in this study. The first class sample is learning with Differentiated Instruction approach and the second class with the conventional learning. Data obtained using research instruments consisting of pre-test and post-test. Based on the results of data processing, it was obtained: (a) the mean achievement of communication ability of the students of Differentiated Instruction class is 77.37 in the medium level and the student of conventional class (75.87) in the medium level too; (b) to improve students’ mathematical communication ability, Differentiated Instruction approach is better to use. From the data that has been obtained, the effect of Differentiated Instruction is to improve students’ mathematical communication ability.
Analysis of higher order thinking skills 8th grade students in math problem solving
Authors: Rohman F M A , Riyadi R , Indriati D 
Published: March 2020

Abstract
This study aims to describe the higher order thinking skills of 8th grade students in mathematics problem solving. The sample used was one class consisting of 29 students and the class was selected based on purposive random sampling. Data collected through tests and interview. Data analyzed by descriptive analysis. The students are given mathematics problem solving test which includes HOTS level of analyze, evaluate and create. The result in the analyze level as many as 86.2% of students be able to differentiating, 48.3% of students be able to organizing, and 48.3% of students be able to attributing. In the Evaluate level as many as 72.4% of students be able to checking and 68.9% of students be able to critiquing. In the Create level, as many as 37.9% of students be able to generating, 31% of students be able to planning and 27.6% of students be able to producing.
Effect of geometric parameters on the performance of motorcycle catalytic converters
Authors: Lapisa R , Halim A G , Sugiarto T , K Arwizet , Martias M , Maksum H , Krismadinata K , Ambiyar A 
Published: March 2020

Abstract
The critical environmental issues of the Indonesian automotive market growth are the increase in air pollution. Vehicle exhaust emission can cause significant problems for the human health and the environment. Therefore, vehicle emission control is indispensable to mitigate the environmental problem. One of the most widely used methods to reduce automotive emission is utilization of catalytic converter in exhaust system. In fact, the catalyst performance in the reduction of noxious gases depends on its material and geometric design. This study aims to evaluate the effect of geometric parameter on the performance of motorcycle catalytic converters. In this experimental study, the catalytic converter made of brass foil plate is mounted on motorcycle muffler. The effectiveness of three catalyst geometry models namely flat perforated plate, folded perforated plate and rolled brass sheet, will be evaluated in relation to the reduction of hydrocarbon (HC) and carbon monoxide (CO) content. HC and CO emission levels are measured by four gas analyzers. The results show that the geometric parameter has a significant effect on HC and CO’s composition in the exhaust gas. For idle speed test, the second geometry model of catalyst presents the best performance in reduction of Hydrocarbon and CO2 concentration.
Peculiarities of electron emission from high-density deep levels of nanodefects in oxygen-implanted silicon
Authors: Danilov D V , Vyvenko O F , Loshachenko A S , Sobolev N A 
Published: March 2020

Abstract
The peculiarities of electron emission from electronic states of nanodefects formed at the early stages of oxygen precipitation in oxygen-implanted silicon annealed at 700°C were investigated with a combination of capacitance and current transient spectroscopy of the space charge region (SCR) in semiconductors. It was established that the particular properties of acceptor-like states are due to their high density and their localization at the back side of the implanted region. A model is suggested that explains an apparent emission rate slowdown and the appearance of an unexpected sign of capacitance relaxation signal as a result of the non-monotonic shape of the potential of the Schottky-diode.
Analysis of the 7x7 to 5x5 superstructure transition by RHEED in the synthesis of Ge on Si (111) in an MBE installation
Authors: Dirko V V , Lozovoy K A , Kokhanenko A P , Kukenov O I 
Published: March 2020

Abstract
In this paper, we consider the 7×7 to 5×5 superstructure transition during the synthesis of Ge epitaxial layers on a Si (111) surface in its temperature range from 250 to 700 °C. This transition is investigated by reflection high-energy electron diffraction (RHEED). As a result, the dependences of the critical thickness of the 7×7 to 5×5 superstructure transition on the substrate temperature are obtained for the first time.
Influence of plasma on electrophysical properties of the GaP/n-Si isotype heterojunction grown by PE-ALD
Authors: Baranov A I , Uvarov A V , Kudryashov D A , Morozov I A , Gudovskikh A S 
Published: March 2020

Abstract
The work is devoted to studying the influence of an additional step of argon plasma treatment on the quality of the GaP/n-Si isotype heterojunction grown by plasma-enhanced atomic-layer deposition (PE-ALD). Deep-level transient spectroscopy measurements demonstrated that argon plasma leads to the formation of defects with a high concentration in silicon wafers, unlike the PE-ALD mode without a step of hydrogen or argon plasma treatment. In addition, GaP layers obtained by PE-ALD have defects with an activation energy of 0.40 eV and 0.62 eV for processes with and without argon plasma treatment, respectively.
2D electrons and 2D plasmons in AlGaN/GaN nanostructure under highly non-equilibrium conditions
Authors: Loginov L A , Shalygin V A , Moldavskaya M D , Vinnichenko M Ya , Firsov D A , Maremyanin K V , Sakharov A V , Zavarin E E , Arteev D S , Lundin W V , Kauppinen C , Suihkonen S 
Published: March 2020

Abstract
We report on studies of electrically excited non-equilibrium 2D electrons and 2D plasmons in an AlGaN/GaN nanostructure. Optical access to 2D plasmons is provided by means of a metal grating fabricated at the nanostructure surface, while the properties of 2D electrons are examined in the samples without metal grating. The paper focuses on the creation of highly non-equilibrium conditions when the effective temperature of 2D electrons is much higher than the crystal lattice temperature. Such conditions are realized by applying short electrical pulses with a low repetition frequency. A method has been developed for independently determining the temperature of hot electrons and the temperature of the crystal lattice under an applied electric field. It has been shown that under highly non-equilibrium conditions the spectral density of terahertz electroluminescence of 2D plasmons can significantly exceed that of 2D electrons at a certain frequency.