Peningkatan produksi suatu industri selalu diikuti oleh peningkatan produksi limbah yang dihasilkan. Industri batik skala rumah tangga umumnya juga belum memiliki instalasi pengolahan limbah cair sehingga limbah langsung dibuang ke lingkungan atau badan air. Hal ini memberikan dampak yang buruk terhadap lingkungan. Penelitian ini bertujuan membuat suatu teknologi pengolahan limbah cair menggunakan metode elektrokoagulasi yang diintegrasikan dengan sistem filter dan menguji efisiensinya terhadap kenaikan kadar keasaman limbah dan penurunan jumlah padatan terlarut (TDS) dari limbah tersebut. Sampel yang digunakan merupakan limbah batik dari salah satu industri batik di kota Jambi sejumlah 20 liter. Elektroda yang digunakan terbuat dari aluminium sebagai anoda dan besi sebagai katoda. Jumlah katoda dan anoda masing-masingnya adalah 4 buah dengan ukuran 60cm x 30cm x 3cm. Tegangan yang digunakan adalah 40 Volt dengan memvariasikan jarak antar elektroda dan waktu pengolahan limbah. Sebelum limbah diolah menggunakan reaktor dilakukan penyaringan dan analisis karakter awal terlebih dahulu.  Hasil penelitian menunjukkan efisiensi reaktor elektrokoagulasi dalam menaikkan pH mencapai 60% hingga 123% dengan rata-rata kenaikan pH 80,83%. Pada perlakuan yang sama, metode elektrokoagulasi memiliki efisiensi dalam menurunkan konsentrasi TDS hingga 50,56 %. Hal ini menunjukkan bahwa metode ini cukup efektif dalam proses pengolahan limbah cair hingga sesuai baku mutu limbah cair.

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The subsurface data acquisition in seismic eksploration usually using expensive equipment. In this work, a low-cost seismic equipment system has been developed for receive and record seismic wave. This system consist of mikrocontroller and software LabView that connected to PC. The subsurface low signals is recorded by geophone and through the amplifier instrument non-inverting. Then, the digital signals is prosessed by Mikrocontroller and visualize by LabView. Output of seismic measurement using this system design are travel time and amplitude. Travel time is used to modelling density and wave velocity to generate wave model. The expected model can give us value of density and wave velocity to obtain the anomaly. It has been tested using 1 geophone and successfully showed the wave, amplitude, and travel time.

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The exhaust gas monitoring system in the coffee roasting process continues to be developed considering the need for more complex roasting coffee beans information. The integrated gas sensor is designed by utilizing a microcontroller controller to see the exhaust gas during the roasting process. The exhaust gas produced during the roasting process is monitored by integrating sensors device to measure exhaust gases (CO, CO2, NOx and SO2). Furthermore, measurements were made by monitoring exhaust gas during roasting of Arabica, Liberica and Robusta coffee beans from Jambi province. The results showed that the total CO concentration in Liberica coffee was 2,121 ppm, Robusta 1,930 ppm and Arabica 1,535 ppm while for CO2 was Liberica 21.3 ppm; Robusta is 22.2 ppm; Arabica is 22.4 ppm, and for NOx is Liberica 303 ppm; Robusta 304 ppm; Arabica is 287 ppm, and the SO2 content for all types of coffee is 0 ppm. The highest exhaust gas concentration occurs after roasting lasts > 20 minutes and at a temperature of 210 - 230°C. It concluded that the integrated gas sensor can be used for the measurement of exhaust gas in the process of coffee beans roasting with the results of measurement of CO exhaust concentration in Liberica coffee is higher than Robusta and Arabica coffee beans.