Few researches have been concerned about relation between childrenâs spatialthinking and number sense. Narrowing for this small research, we focused onone component of spatial thinking, that is structuring objects, and onecomponent of number senses, that is cardinality by determining quantities. Thisstudy focused on a design research that was conducted in Indonesia in which weinvestigated pre-school childrenâs (between 2 and 3.5 years old) ability inmaking structured arrangement and their ability to determine the quantities bylooking at the arrangements. The result shows us that some…
This paper is about PMRI, the Indonesian version of realisticmathematics education developed in the Netherlands. It is a movement toreform mathematics education in Indonesia. What and why PMRI andthe problems and challenges it faces in its development. It began as asmall experiment ten years ago, now becomes a national movement.Keywords: PMRI, realistic mathematics education
Penelitian kuasi eksperimen ini bertujuan untuk mengetahui dampak daripendidikan matematika realistik (PMR) terhadap peningkatankemampuan pemecahan masalah matematik (KPMM). Desain penelitianyang digunakan adalah kelompok kontrol non-ekuivalen dengan subjekpopulasi seluruh siswa SMP di Kota Yogyakarta yang berasal darisekolah level rendah (C), sedang (B), dan tinggi (A). Dari masing-masinglevel sekolah diambil satu sekolah kemudian dari setiap sekolah yangterambil diambil satu kelas eksperimen yang mendapat PMR dan satukelas kontrol yang mendapat pembelajaran biasa (PB). Instrumen yangdigunaka…
Many researchers assume that people are creative, but their degree ofcreativity is different. The notion of creative thinking level has beendiscussed .by experts. The perspective of mathematics creative thinkingrefers to a combination of logical and divergent thinking which is basedon intuition but has a conscious aim. The divergent thinking is focusedon flexibility, fluency, and novelty in mathematical problem solving andproblem posing. As students have various backgrounds and differentabilities, they possess different potential in thinking patterns,imagination, fantasy and performance; there…
Learning about decimals is an important part in mathematics. However at the same time, decimals are known as the  abstract numbers for students. Mostly in Indonesia, decimal is taught only as another notation for fractions or percentages. There are no meaningful references  for  them  such as  the  use of  concrete  situations. This study aimed at investigating one situation that enables students to learn about decimals in a meaningful way,  i.e.  measurement  activities.  Design research was chosen to reach the research goal. Realistic …
This study is a quasi-experimental research with pretest-posttest control group design, which aims to determine (1) the tendency of students in using various media scaffolding based on gender, and (2) effect of media scaffolding on increasing understanding of students? geometry concepts. Media scaffolding used this study is chart, props, and visual. The population was the fifth grade students of State Elementary School I Gunung Terang (total 40 students), Bandar Lampung, Indonesia of the academic year 2015-2016. The sample was total sampling, respectively 20 students in the experimental class …
Several studies related to mathematical proof have been done by many researchers on high-level materials, but not yet examined on the material of transformation geometry. The aim of this research is identification learning obstacles pre-service teachers on transformation geometry. This study is qualitative research; data were collected from interview sheets and test. There were four problems given to 9 pre-service mathematics teachers. The results of this research were as follows: learning obstacles related to the difficulty in applying the concept; related to visualize the geometry object; re…
Mangga gedong gincu menjadi komoditas hortikultura yang cenderung lebih disukai walaupun harga jualnya lebih tinggi dibandingkan dengan varietas mangga lainnya seperti Aromanis, Cengkir dan Kaweni. Hal ini menandakan mangga gedong gincu memiliki nilai ekonomis tinggi dan berpeluang untuk meningkatan kesejahteraan petani. Namun demikian, usahatani ini mempunyai risiko yang tinggi karena sangat dipengaruhi oleh musim sehingga umumnya mangga gedong gincu tidak tersedia sepanjang tahun walaupun permintaan sangat banyak. Untuk itu petani menerapkan teknologi off season agar produksi bisa dilakukan …
Maize (Zea mays L.) is an important food crop in Indonesia as a source of carbohydrates. The extent of land conversion reduces maize productivity. The experiment aimed to increase the growth and yield of maize in Ultisol which was carried out in the experimental garden of the West Java Horticultural and Various Seed Plant Development Center from October 2017 to March 2018. The Phosphate Solubilizing Bacteria (PSB) and organic ameliorant application test used the factorial randomized block design (RBD) method consisted of two factors. The first factor is PSB and organic ameliorant which consist…
Suatu percobaan di rumah plastik menggunakan media tanah dilaksanakan untuk mempelajari pengaruh kombinasi dosis pupuk kandang ayam dan konsentrasi zat pengatur tumbuh atonik terhadap pertumbuhan dan hasil tanaman krisan. Percobaan dilaksanakan di di dalam Screen House, Kampung Pasir Kuning Desa Pasir Langu Kecamatan Cisarua Kabupaten Bandung Barat. Terletak pada ketinggian 1200 meter dpl dengan order tanah andisol, dan kemasaman tanah (pH) 6. Percobaan dilaksanakan dari bulan Maret 2017 sampai dengan bulan Juli 2017. Rancangan lingkungan yang digunakan yaitu Rancangan Acak Kelompo…
Hasil penelitian ini menunjukan lokasi dan luasan yang sesuai untuk ditanami tanaman akar wangi. Ordo kesesuaian lahan untuk tanaman akar wangi terdiri dari ordo S (sesuai) dengan luas 30.095 hektar atau sebesar 83,57% dari luas area penelitian dan ordo N (tidak sesuai) dengan luas sebesar 5.917 hektar atau sebesar 16,43% dari luas area penelitian. Tingkat Kelas yang diperoleh yaitu S2 (cukup sesuai) dengan luas 11.157 hektar atau 30,98%, S3 (sesuai marginal) sebanyak 18.938 hektar atau 52,59% dan N (tidak sesuai) dengan luas 5.917 hektar atau sebesar 16,43%. Pada tingkat sub kelas terdapat 11…
Budidaya jeruk keprok pada umumnya menggunakan bibit yang berasal dari perbanyakan cara okulasi. Okulasi adalah salahsatu perbanyakan untuk meningkatkan mutu bibit dengan cara mempelkan mata tunas sebagai batang atas pada suatu irisan kulit pohon lain sebagai batang bawah, sehingga tumbuh bersatu menjadi tanaman baru. Penelitian ini bertujuan untuk mengetahui daya tumbuh bibit jeruk sistem perbanyakan okulasi pada batang bawah dan mata tempel yang berbeda. Percobaan dilaksanakan mulai Agustus sampai dengan Oktober 2018 di Kecamatan Karangpawitan Kabupaten Garut Jawa Barat. Metode yang di…
Banana cropping patterns applied by farmers in West Java using polyculture systems. This system can build a diversity of plant species that are mutually beneficial. This study aims to determine the level of biodiversity of the banana ecosystem in West Java using vegetation analysis. The study was conducted in six districts in the area of ??West Java (Garut, Purwakarta, Bandung, Cianjur, Bogor and Banjar) from February to April 2019. The materials used were all types of plants found in each observation location, while the tools used in the study this is the Global Positioning System (GPS), long…
The aim of this research was to know the production performance of Holstein Friesian dairy cow on first lactation based on milk production records and length of lactation. The research was done at PT. Ultra Peternakan Bandung Selatan, West Java. A method of the research used descriptive analysis. Milk production and length lactation period on first lactation were used as production performance variable. The data obtained from 2011-2015 production record of 750 dairy cows on first lactation. Production performance of dairy cows on first lactation were have average daily milk production of 18,94…
Biostimulants plays an important role in the phytoremediation process of soil contaminated with hydrocarbon compounds. This experiment aims to determine the best treatment between N-fixing bacteria (BNF) and cow manure (CM) that can improve oil-polluted soil. The experiment was conducted in January-April 2019 at Kebun Percobaan Ciparanje Fakultas Pertanian Universitas Padjadjaran, Jatinangor, Sumedang, used a randomized block design method with four combinations (without BNF + without CM, Azotobacter sp. + without CM, without BNF + CM dose of 100% and Azotobacter sp. 4% + CM dose of 100%). The…
The study was conducted from January to February 2014 in the Broiler Cage Stage Cikandang Village, Rumpin District, Bogor Regency, West Java. The study aims to examine the utilization of fermented banana peels on protein consumption, crude protein digestibility and protein mass of broiler chicken meat. The material used was 120 broiler chickens (unsex) with an average body weight of 475 ± 0.98 g / head for 14 days, rumen fluid, banana peels and rations arranged in iso energy and iso protein. The experimental design used was a completely randomized design (CRD) with 4 treatments and 6 replicat…
The agronomic characteristics of Robusta coffee plants are influenced by several factors, one of which is altitude. Robusta coffee can grow optimally at an altitude of 400-1,000 meters above sea level with a temperature of 21-24 °C. Pejawaran sub-district is known as a mountainous area with a height of 900-1600 m above sea level. This research was conducted in July to September 2019 in the coffee garden of Sarwodadi Village, Pejawaran District, Banjarnegara Regency. The selection of research sites was carried out by conducting a survey where 3 altitudes were selected that had a greater number…
With respect to the problem of big volume, large weight and high power consumption of lunar sampler nowadays, the paper firstly described a novel flexible mini lunar regolith sampler. Then the vibration model of it is established while drilling. The drilling efficiency can be improved more effectively by controlling the lunar regolith sampler always in the resonance state. But the dynamical modeling of the sampler-regolith system is difficult to obtain and time varies when the sampler is in different depth in the lunar regolith. So we present a method of the vibration frequency fuzzy adaptive …
A new solar electric bicycle design and study were carried out on in this paper. Application of CAD technology to establish three-dimension geometric model, using the kinetic analysis on the frame and other parts for numerical simulation and static strength analysis for the vehicle model design, virtual assembly, complete frame dynamics analysis and vibration analysis, with considering other factors, first on the frame structure improvement, second on security of design calculation analysis and comparison, finally get the ideal body design. DOI: http://dx.doi.org/10.11591/telkomnika.v11i10.3…
Mobile payment is a form of payment transaction processing where the payer utilizes mobile communication methods together with mobile devices to initiate, authorize or complete payment. Hence, with the huge increase in mobile device usage, the retail sector will be able to collect large volumes of data. Unfortunately, most Malaysians still do not make full use of digital payments or cashless payments. Consumers in South East Asia still tend to use money or bank cards, and companies have been "limitedly effective" in encouraging a cashless revolution. The objective of this study was to identify…