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Abstrak :
This book discusses new techniques for detecting, controlling, and exploiting the impacts of temperature variations on nanoscale circuits and systems. A new sensor system is described that can determine the temperature dependence as well as the operating temperature to improve system reliability. A new method is presented to control a circuit’s temperature dependence by individually tuning pull-up and pull-down networks to their temperature-insensitive operating points. This method extends the range of supply voltages that can be made temperature-insensitive, achieving insensitivity at nominal voltage for the first time.

Abstrak :
Telah berhasil dibangun pengendali temperatur probe dingin pada sistem karakterisasi material termoelektrik menggunakan kendali PID dengan metode tuning IMC dan telah diuji pada tiga temperatur, yaitu 10°C, 15°C, dan 20°C. Pada temperatur 10°C berhasil stabil dengan gangguan laju konduksi 8,8 W, temperatur 15°C berhasil stabil dengan gangguan laju konduksi 18 W, dan temperatur 20°C berhasil stabil dengan gangguan laju konduksi 19 W. Pengujian tersebut membutuhkan temperatur dingin konstan dan temperatur panas sebagai pemberi gangguan. Untuk membuat temperatur dingin digunakan sel peltier dengan daya 30 W, sementara untuk membuat gangguan panas digunakan empat elemen pemanas konfigurasi paralel dengan daya total 95 W. Selain itu, penelitian ini dilakukan dalam vakum dengan tekanan 2162 uHg. Menggunakan mikrokontroler untuk memproses pengendalian temperatur probe dingin dan untuk mengirim output pengendalian menuju sel peltier juga membaca temperatur pada probe dingin. Output pengendalian berupa sinyal PWM yang dapat divariasikan duty cycle-nya. ......A cold probe temperature controller on thermoelectric material characterization system has been successfully built using PID control with the IMC tuning method and has been tested at three temperatures: 10°C, 15°C, and 20°C. At a temperature of 10°C successfully stabilized with a conduction rate disturbance of 8,8 W, at a temperature of 15°C successfully stabilized with a conduction rate disturbance of 18 W, and at a temperature of 20°C successfully stabilized with a conduction rate disturbance of 19 W. The test requires a constant cold temperature and hot temperature as a disturbance. To create cold temperatures, a peltier cell with a power of 30 W is used, while to create a heat disturbance, four heating elements are used in parallel configuration with a total power of 95 W. In addition, this research was carried out in a vacuum with a pressure of 2162 uHg. Using a microcontroller to process the temperature control of the cold probe and to send the control output to the peltier cell also reads the temperature on the cold probe. The control output is in the form of a PWM signal whose duty cycle can be varied.

Abstrak :
The temperature and humidity inside poultry houses are highly coupled through nonlinear psychrometric processes, and the limitation of actuators makes this type of system difficult to control. To understand the dynamics of such systems and further to design a suitable controller, in this study, the mathematical model for a closed poultry house was derived from the governing equations of the various components related to the poultry house, including the energy and mass balance and the psychrometric correlations of the moist air. The model was simulated and the simulation result was compared to the data collected experimentally for model verification and control gains estimation. Under the assumptions of 70 percent Active Mixing Volume (AMV) with the constant maximum ventilation rate in the case study, the temperature and the relative humidity simulated results were in the good agreement with the real physical plant data. At the front, the middle and the rear part of the poultry house, the root-mean-square error (RMSE) obtained for internal temperatures are 1.17oC, 0.68oC, and 0.46oC, respectively. And those data for relative humidity are 4.31%, 8.07%, and 53.54%, respectively.

Abstrak :
The temperature and humidity inside poultry houses are highly coupled through nonlinear psychrometric processes, and the limitation of actuators makes this type of system difficult to control. To understand the dynamics of such systems and further to design a suitable controller, in this study, the mathematical model for a closed poultry house was derived from the governing equations of the various components related to the poultry house, including the energy and mass balance and the psychrometric correlations of the moist air. The model was simulated and the simulation result was compared to the data collected experimentally for model verification and control gains estimation. Under the assumptions of 70 percent Active Mixing Volume (AMV) with the constant maximum ventilation rate in the case study, the temperature and the relative humidity simulated results were in the good agreement with the real physical plant data. At the front, the middle and the rear part of the poultry house, the root-mean-square error (RMSE) obtained for internal temperatures are 1.17oC, 0.68oC, and 0.46oC, respectively. And those data for relative humidity are 4.31%, 8.07%, and 53.54%, respectively.

Abstrak :
Kelahiran prematur merupakan masalah berkepanjangan yang berhubungan dengan risiko morbiditas dan mortalitas bayi. Sistem inkubator dikemukakan untuk meminimalkan risiko kelahiran prematur. Salah satu sistem otomasi yang digunakan pada inkubator adalah regulasi panas dan kelembaban. Regulasi panas dan kelembaban umumnya dikendalikan menggunakan sistem kendali feedback seperti PID dan fuzzy-logic PID. Material PTC adalah material yang biasa digunakan sebagai pemanas ruangan. Sistem kendali digunakan untuk mengendalikan pemanas PTC agar mencapai suhu yang diinginkan. Pada penelitian ini dilakukan empat jenis eksperimen untuk mengevaluasi performa PTC sebagai pemanas inkubator dengan PID dan fuzzy logic-PID sebagai sistem kendali. Pertama, dilakukan uji karakteristik hambatan PTC terhadap suhu. Selanjutnya, PTC dihubungkan dengan kipas dan digunakan sebagai pemanas inkubator untuk diuji performa material sebagai pemanas. Eksperimen ini meliputi uji step response untuk mengetahui parameter yang diperlukan untuk tuning PID. Parameter ini kemudian digunakan pada kendali PID. Ditambah itu, diberikan implementasi fuzzy-logic pada PID untuk mengevaluasi perbandingan performa pengendali dengan performa inkubator yang sudah ada. Hasil penelitian yang dilakukan menunjukkan bahwa pemanas PTC dapat memanaskan udara pada inkubator dan dapat dikendalikan menggunakan sistem kendali PID dan fuzzy-logic PID. Meski performa lebih buruk dibandingkan sebagian besar inkubator yang sudah ada, konsumsi daya PTC yang hanya membutuhkan 120 Watt bersifat lebih hemat dibandingkan inkubator eksisting yang menghabiskan daya 350 – 400 Watt. ......Premature birth is an everlasting problem that relates to the risk of morbidity and mortality of prematurely-birth infants. Incubator system was invented to minimize the risk. One of the automation systems that are used in incubator is heat and humidity regulation. This particular regulation system commonly uses feedback control system such as PID and fuzzy-logic PID. PTC material is the material commonly used as a room heater. In order to meet the desired temperature, control system is implemented to the PTC. This research evaluates the performance of PTC as incubator heater with PID and fuzzy logic-PID as the control system of choice. First, characteristic test is performed at the material to evaluate its heating performance. This test costists of step response test to determine parameters required to perform PID tuning. The obtained parameter is then calculated to determine the tuned PID parameter gains. After that, fuzzy logic is implemented to the system which controls those parameters based on the measured error and change of error. The result of both experiments are compared to existing incubators used in publications. The result of this comparison shows that PTC is capable of warming incubator to desired temperature and can be controlled with PID and fuzzy-logic PID. While the performance is inferior to majority of existing incubators, this tradeoff of more efficient power (120 Watt versus 350 – 400 Watt) can be considered as an alternative.