Abstract.A refrigeration system to maintain a desired compartment temperature usually uses a thermostat as an on-off controller. In fact, the thermostat has some disadvantages. The main problem of system which is related to the thermostat is the biggest energy consumption in household appliances. In this paper, to solve the problem was designed a new PID controller based on an Arduino Uno R3 with application to a household refrigerator. In this case, the Arduino Uno was uploaded with PID controller algorithm. Then, in implementation to determine controller parameter values was defined new criteria. After that, to obtain the best refrigeration system performance was also proposed new performance criteria based on experimental data. The experimental results showed that the proposed control system was able to maintain the desired temperature with steady-state error of about 0.044°C. In addition, in steady state the control system for the refrigerator was able to the energy saving of about 30% and it almost did not depend on cooling load quantity. InroductionA household refrigerator can maintain a desired compartment temperature since it employs a thermostat which serves as an on-off controller. In fact, the thermostat has some disadvantages. First, the present of control differential, difference between cut-in or cut-out temperature and setpoint temperature, causes response error that is set consciously according to the working principle of the on-off controller. Thus, the error is embedded in the thermostat. Second, if the differensial is set at a too small value, then the refrigerator will often turn on and off. Consequently, this action can breakdown the compressor [7,17]. Besides that, the action also requires high starting current equals to 4 to 10 times bigger than running current [21].Third , the energy consumption of refrigeration system is the biggest in household appliances [11,13,15].To respond these disadvantages, the researchers developed a new on-off controller. However, this way could not reduce significantly both response error [20] and the energy consumption [12]. Then, PID (Proportional Integral Derivative) controller concept was used to improve the on-off controller [1,2,16,22]. Then, it was followed adaptive control concept [8,9,23]. However, in implementation they had constraints, both of them were determination of control parameters, and control components that were needed to support a control system [5]. For example, to modify from the on-off control system to the PID one it needs to consider adding of safety components to avoid an overheat compressor. Since, the PID one is always working without ever turning off as in the on-off one.To reduce the problem and also to give a better optional controller, then in this paper was designed a new PID control system based on Arduino Uno R3 with application to the refrigerator. In this case, Arduino Uno R3 was uploded with a new PID controller algorithm. Control parameters are proportional gain Kp, integral gain Ki, and derivative gain Kd that were det...

This study aims to determine the effect of variations in drying temperature and concentration of green spinach juice (Amaranthus hybridus l) on spinach milk powder using a rotary vacuum machine. This study uses the research design method used is a factorial randomized block design with 2 repetitions. The treatment design carried out in this study consisted of two factors, namely the drying temperature (T) consisting of 3 levels. The rotary vacuum drying method produces the best characteristics with a moisture content of 2.21%, chlorophyll content of 7.65 mg/l, antioxidant activity of 2024.22 ppm. The results of the best physical analysis were 31.50 seconds of dissolution time, 14.95% yield, 80.18% solubility, 11.35% hygroscopicity, 18.11 Cp viscosity, color intensity L* 63.21, color -a* 7, 00, color b* 26.68.

The purpose of this study was to determine the effect of Trehalose and Telang-Pea (Clitoris ternatea L.) which are used as fillers for Telang-Yellow milk powder. This study used a randomized block design, 3x3 factorial, and 2 replications. Trehalose concentrations (10%, 15% and 20%) and t butterfly pea flower concentrations (0.5%, 1% and 1.5%) were research factors. The results of this study included water content, antioxidant activity, viscosity, yield, solubility, dissolution time, hygroscopicity, color intensity, and preference for taste, color, aroma and after taste. The results showed that water content, hygroscopicity, dissolution time, solubility, yield, pH value, color, and hedonic assessment of taste, color, aroma, and aftertaste were affected by trehalose and eggplant concentrations. The best organoleptic results were obtained with t1b2 samples (0.5% trehalose and 15% Butterfly Pea). The best treatment was the t3b3 treatment with the results of the analysis of water content 2.86%, hygroscopicity 7.15%, amendment 20.00%, soluble time 29.13%, solubility 83.98%, pH 6.72, antioxidant activity 557.77 ppm, color intensity *L 48.01, *a 4.73 and *b 6.10.

Kertasari Kabupaten Bandung, bukan hanya sebagai sentra kentang di Jawa Barat juga membuktikan diri sebagai salah satu daerah pemasok kebutuhan kentang nasional. Kualitas kentang tidak kalah, pasar sasaran pasar sejumlah daerah, seperti Jakarta, Sumatra, Kalimantan, dan beberapa daerah lainnya. mampu menembus pasar ekspor, terutama Singapura dan sejumlah supermarket ternama di Indonesia. Berdasarkan hasil wawancara dan observasi pada kelompok usaha kecil di Desa Cibereum, mengatakan produk hasil olahan keripik kentang yang dihasilkan secara masih tradisional, yang dijual ke daerah sekitar, akan tetapi kualitas hasil produksi keripik kentang belum sesuai tuntutan pasar. Permasalahan Utama yang dihadapi kelompok usaha mitra terkait dengan Kapasitas Kewirausahaan dan Teknologi yang digunakan masih terbatas. Pelaksanaan kegiatan ini, mulai dilaksanakan pada

Pengeringan didefinisikan sebagai penerapan panas dalam kondisi terkontrol untuk menghilangkan sebagian besar air dengan penguapan atau dalam kasus pengeringan beku dengan sublimasi. Tujuan dari penelitian yang dilakukan adalah untuk memproduksi tepung jerami nangka dan membandingkan laju pengeringan jerami nangka pada kondisi pengeringan atmosferik dan kondisi vakum. Hasil penelitian menunjukan bahwa laju pengeringan jerami nangka pada kondisi vakum lebih besar dibandingkan dengan laju pengeringan jerami nangka pada kondisi atmosferik.