Development of Dynamic Local Work Load Measurement Method Using Electromyography (EMG) (an Experimental Measurement with Drilling Activities)

This paper presents a scheme to build a system of musculosceletal maesurement using Electromyography and for measuring physical dynamic workload of local muscles, i.e., drilling activities. Electro-myography (EMG) can be signal of muscle contractions and provides continous record as the analog signal. The result of this dynamic local workload measurement show a nonlinear relationship between peak level power spectra of EMG signal and torque. the work load for drilling 0.8 mm to 5 mm plate activities ranges between 0,1513 to 1, 6979 Joule

Pengembangan Sistem Aquisis Data Kadar Nitrogen Tanah Berbasis Sensor Infra Merah Sebagai Pedoman Penentuan Dosis Pemupukan

Abstract Site specific nitrogen fertilizing  needs an accurate map of soil nitrogen content. The use of sensors operated upon the soil is a promising method since the accurate soil sampling methods are costly and time consuming. The objectives of this research are to determine the relation between soil nitrogen level and near infrared spectrum using artificial neural network (ANN) and to develop soil nitrogen content data acquisition system for static dan dynamic measurement. The results showed that the 1506 nm wavelength can be used to estimate the soil nitrogen content. Furthermore it was found that static measurement showed a better correlation (R2= 0.6286) than the dynamic measurement (R2=0.3111). Combined with the developed ATMega32 microcontroller based display recorder, the precision of N content measurement achieved 0.12% wb with 0.1% wb noise. Keywords : NIR, soil nitrogen level, data acquisition, artificial neural network, precision farming Abstrak Pemupukan unsur hara nitrogen spesifik lokasi membutuhkan sebuah peta nitrogen tanah yang akurat. Penggunaan sensor untuk pengujian tanah dapat dijadikan alternatif menggantikan metode konvensional yang membutuhkan waktu yang lama dan biaya yang mahal. Penelitian ini bertujuan untuk membangun hubungan antara komposisi kadar nitrogen tanah dengan spektra Near Infrared (NIR) menggunakan jaringan saraf tiruan (JST) dan membuat sistem akuisisi data kadar nitrogen tanah pada pengukuran statis dan dinamis. Hasil penelitian menunjukkan panjang gelombang spesifik yang dapat digunakan untuk menduga kadar nitrogen tanah adalah pada panjang gelombang 1506 nm. Hubungan antara kadar nitrogen dan tegangan reflektan pada pengukuran statis menunjukkan hubungan yang lebih baik dengan R2 sebesar 0.6286 dibandingkan pada pengukuarn dinamis dengan R2 sebesar 0.3111. Simulasi sistem akuisisi data  kadar nitrogen tanah menggunakan mikrokontroler ATMega 32 yang dilengkapi dengan display memberikan ketelitian sebesar 0.12% berat dengan noise sebesar ±0.1 % berat. Kata kunci: NIR, kadar nitrogen tanah, akuisisi data, Jaringan Saraf Tiruan, pertanian presisi.Diterima:28 Juni 2011 ; Disetujui: 26 September 201

Desain Model Diagnostik Resiko Ergonomi pada Kelapa Sawit secara Manual

Oil palm harvesting activity is mostly done by ‘human power' manual handling, therefore the activity may cause work safety and health problems.This research is deal with anthropometry, motion study andbiomechanic to find out the risk of manual handling and to develop ergonomic assessment model of oil palm harvesting. This model was designed in the aims to find out better work motion, good procedure and better design of harvesting tool, so the manual harvesting can be done in more safe, efficient and productive. The formula for the appropriate distance between harvester's position and the tree and the length of egrek show that oil palm harvesting for more than 16 m bunches's height is not safe with ‘egrek'. Critical load for neck, shoulder and forearm are 21.85 N, 1091.96 N and 1634.31 N. Ergonomic risk assesment's tool of oil palmmanual harvesting was designed with the parameter: appropriate distance (dt), the length of egrek (lp), critical range of motion (CRM) and critical load (CL) for neck, shoulder and forearm

Development of Dynamic Local Work Load Measurement Method Using Electromyography (EMG) (an experimental measurement with drilling activities)

This paper presents a scheme to build a system of musculosceletal maesurement using Electromyography and for measuring physical dynamic workload of local muscles, i.e., drilling activities. Electro-myography (EMG) can be signal of muscle contractions and provides continous record as the analog signal. The result of this dynamic local workload measurement show a nonlinear relationship between peak level power spectra of EMG signal and torque. the work load for drilling 0.8 mm to 5 mm plate activities ranges between 0,1513 to 1, 6979 Joule

Pengembangan Sistem Aquisisi Data Kadar Nitrogen Tanah Berbasis Sensor Infra Merah Sebagai Pedoman Penentuan Dosis Pemupukan

Site specific nitrogen fertilizing needs an accurate map of soil nitrogen content. The use of sensors operated upon the soil is a promising method since the accurate soil sampling methods are costly and time consuming. The objectives of this research are to determine the relation between soil nitrogen level and near infrared spectrum using artificial neural network (ANN) and to develop soil nitrogen content data acquisition system for static dan dynamic measurement. The results showed that the 1506 nm wavelength can be used to estimate the soil nitrogen content. Furthermore it was found that static measurement showed a better correlation (R2= 0.6286) than the dynamic measurement (R2=0.3111). Combined with the developed ATMega32 microcontroller based display recorder, the precision of N content measurement achieved 0.12% wb with 0.1% wb noise