Judul: Design and Performance Test of Egrek with Shock and Spring System for Palm Oil Harvesting
Abstrak: Egrek merupakan alat bantu panen yang digunakan untuk memotong pelepah dan tandan buah segar kelapa sawit dengan cara ditarik. Alat bantu panen egrek kelapa sawit hasil modifikasi pada dasarnya dirancang dengan memanfaatkan ruang pergerakan dari mata pisau yang lebih optimal, serta memanfaatkan benturan terhadap sentakan antar komponen ring yang terjadi sangat keras pada alat bantu egrek panen dari mekanisme tarik dan sentak, oleh operator panen. Alat bantu egrek panen hasil modifikasi menjadikan pemanenan dengan menggunakan egrek yang dirancang menjadi lebih mudah dan ringan hingga 0,3 kg dibanding egrek konvensional biasa yang ada di lapangan, ditambah lagi dengan sistem pegas dan sistem penguncian (Spring lock and snap system) yang terpasang pada rancangan sebagai pemanfaatan energi potensial dalam bentuk penyimpanan dan penambahan tenaga bagi operator (pekerja panen) ketika melakukan awalan pemberian gaya tarik terhadap galah, serta dengan mata pisau egrek yang tajam dapat memotong pelepah serta tandan buah segar kelapa sawit lebih kuat dan cepat 18,30 detik/pohon, yang artinya mampu meningkatkan produktivitas panen hingga 38,4% dari egrek konvensional sebelumnya, sehingga dari penggunaan waktu dan tenaga pada proses pemanenan kelapa sawit akan lebih mudah, ringan, kuat dan cepat serta juga menjadikan proses pemanenan menjadi lebih efektif dan efisien., Egrek is a harvesting tool that is used to cut the midrib and fresh fruit bunches of oil palm by pulling it. The modified oil palm egrek harvesting aids are basically designed by utilizing the movement space of the blade more optimally, as well as taking advantage of the impact on the jerks between ring components that occur very hard on the egrek harvesting aids from the pull and jerk mechanism, by the harvest operator. The modified egrek harvesting tool makes harvesting using egrek which is designed to be easier and lighter up to 0.3 kg compared to ordinary conventional egrek in the field, coupled with a spring system and a lock system (Spring lock and snap system) installed on the the design as the utilization of potential energy in the form of storage and additional energy for operators (harvest workers) when pre-applying the pulling force on the poles, and with a sharp egrek blade it can cut the midrib and fresh fruit bunches of oil palm more strongly and quickly 18.30 seconds /tree, which means it is able to increase harvest productivity up to 38.4% from the previous conventional egrek, so that the use of time and energy in the oil palm harvesting process will be easier, lighter, stronger and faster and also make the harvesting process more effective and efficient.
Keyword: effective and efficient tool, egrek, midrib pruning, oil palm harvester

Judul: Studi Antropometri dan Gerak Kerja Pemanen Kelapa Sawit serta Aplikasinya untuk Penyempurnaan Desain Alat Panen Sawit (Egrek dan Dodos)
Abstrak: Oil palm harvesting process using conventional tools named pole and curve knife and chisel may cause risk of injury. Good matching and compatibility between human and tools dimensions is necessary to gain optimum performance. So an anthropometric approach in order to obtain an ergonomic design is needed. The purpose of this study was to analyze suitable dimentional of pole and curve knife and chisel based on natural range of motion and anthropometric data of harvester’s, and to recommend a better design of pole and curve knife and chisel which are more ergonomic. The result range of motion analysis show that the upper body such as the neck, shoulder and forearm determine the level of risk and can cause risk of injury. Simulation result obtained an egronomic stem length of chisel is 1 meter with 3 connected stem, and seen from technical aspect is 1.5 meter with 2 connected stem. While the length of pole and curve knife stem is 4 meter with 5 connected stem. In addition to that, this research revealed that the total length of pole and curve knife stem needed in a certain harvesting activity can be formulated as : ( ) , where h is the high of cutting target, t is the high of harvesters.
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Judul: Pengaruh Pairing pada Isotop Sn dengan Menggunakan Pemodelan Sembilan Tingkat Energi
Abstrak: Formation of the neutron-rich tin isotopes (Sn isotopes) is the one of the interesting topics in the field of nuclear reaction, especially regarding the stability of the heavy nuclei. Calculations of total energy using the BCS approach using five energy levels can only calculate the total energy up to Sn50132. On the other hand, the experiment continues and has exceeded the formation of isotopes. Therefore, there is need for a new model to accomadate more neutrons. In this research, Sn isotopes is modelled using nine energy levels and constant interaction potential to explain the pairing phenomenon up to Sn50154. However, to obtain more accurate results, other methods to minimize the differences with the experimental results are clearly needed here.
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