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Study of Zwitterionic Homopolymer Polysulfobetaine and Gel Properties in Various Solutions of Different Anion Species and Cation Valences
Get PDFZwitterionic homopolymer polysulfobetaine (PBET) gels were synthesized using free radical polymerization. The effect of temperatures on adsorption behavior of the gel and transition temperature of the polymer in various solutions of LiCl, KCl, NaCl, Al(NO3)3, Zn(NO3)2, and NaNO3 were studied. The tendency of poly(BET)s transition temperature in Cl solutions very identical. All of poly(BET) solution resulted in Upper Critical Temperature (UCST). Its number increased along with the elevation of salt concentration. The number declined again when the concentration was too high. BET gel successfully adsorbed various ions with the amount of adsorption tendency of LiCl < NaCl < KCl
Bioethanol Production from Wastewater of Brown Sugar Home Industry in Kediri via Enzymatic Hydrolysis and Fermentation
Get PDFBioethanol is ethanol whose main ingredients are from plants and generally use a pharmaceutical process. Therefore, Indonesia still needs a more effective source of bioethanol as fuel. Bioethanol production from vegetable waste is a realistic solution, one example is waste from the brown sugar home industry. The purpose of this research is to innovate the production of bioethanol by utilizing sap sugarcane waste in a brown sugar industry home using the Enzyme Hydrolysis and Fermentation Method. The process of making bioethanol is the raw material preparation stage, the hydrolysis stage, and the fermentation stage. The first stage, the preparation of raw materials is done by filtering the molasses waste and then dissolving it with distilled water in 2000 mL Erlenmeyer. the second stage, the hydrolysis stage, is to hydrolyze the molasses solution according to the predetermined ratio variables, by going through two stages in the hydrolysis stage, namely liquefaction and saccharification. In the liquefaction process, -amylase is added at a temperature of 90oC and heated on a hot plate stirrer for 2 hours. Then the saccharification stage was carried out by adding the enzyme gluco-amylase at a temperature of 65oC for 4 hours. The third stage, the fermentation stage, was carried out with variations of bread and yeast tape with the additional variables of 5%, 10%, and 15% nutrient (2% urea and 3%). Fermentation will be carried out for 3 days. The results showed that the maximum sugar content was achieved by using a concentration ratio of sugarcane juice: water = 1:0 with an enzyme hydrolysis process of 196.08 g/L. The maximum bioethanol content after fermentation was 18.6% and reducing sugar of 10.98 g/L was achieved by using 10% baker's yeast at a concentration of sugar cane juice: water ratio = 1:1. The maximum bioethanol content after the fermentation process was 12.96% and the reducing sugar was 27.78 g/L was achieved using 10% tape yeast at a concentration ratio of sugarcane juice: water = 1:1
The Characteristic of Variable Frequency Drive for Water Flow Control in the SFC Plant
Get PDFOne of several techniques to control fluid flow-rate through a pump is using variable frequency drive. This paper presents how experiment be able to perceive the characteristic of variable frequency drive (VFD) to control water flow-rate in the Simulator Flow Control (SFC) plant. The SFC plant is developed for a fluid course learning simulator. The user would be able to set the desired value of frequency or flow-rate through a convenient interface. To provide it, the characteristic of VFD-frequency-to-flow-rate must be firstly observed, as reported in this paper. The fluid flow-rate control is designed without an electric valve, but using VFD to drive the 250 Watt water pump. In this first development, the SFC Plant successfully work with various water flow-rate from 2 Liter per minute until 20 Liter per minute by changing the frequency input of VFD. The water flow-rate was measured by manual rotameter, the flow sensor has not been applied yet in this first development. In this experiment, the VFD’s frequency was set from 10 Hz to 36 Hz with 2 Hz intervals. Result showed that VFD frequency is proportional to water flow-rate. The higher frequency given to VFD, the faster rotational motor of water pump generated and then given rise to water flow-rate. Using linear graphic approach, the characteristic is shown through the linearity coefficient of 0,68 and constant value of 3.43. This characteristic value would be useful for open-loop-control and user interface programming in next step of development
Estimation of the Catastrophic Risk using Mixture Models
Get PDFIndonesia is one of the countries in the world that is susceptible to various types of natural disasters such as earthquakes, floods, etc. These events do not occur very often, however, they cause massive financial loss. This risk of loss is termed as a catastrophic risk where it not only affects the individual but also the government and at the same time posing a threat to insurance companies if they do not have sufficient resources to make a payment of claims. However, due to the complexity and uncertainty of natural hazards, measuring this risk is quite challenging. This paper proposes an estimation method of the catastrophic risk based on Value-at-Risk (VaR) of total loss from natural disasters in Indonesia. A key issue for estimating VaR is to fit an appropriate distribution. Extreme value distribution, such as Generalized Pareto Distribution (GPD) has been used to assess the tail behavior of extreme loss. However, this distribution does not give any information about the central behavior that may affect the estimation of the model parameter in GPD. Therefore, this paper utilized mixture models that combine the parametric form of loss distributions such as gamma, Weibull, and lognormal distribution with GPD. The result shows that VaR estimations are quite different under different mixture models and confidence levels. In addition, the lognormal-GPD model is selected as the best model that fits data best with the highest value of Log-likelihoo
Design of Fault Tolerant Control on Wind Turbine Speed Control Based on Bias Fault Estimation Method with Optimization l_0 Norm Constraint
No full textThe availability of onshore wind power plant systems (PLTB) reaches 98%, but the maintenance costs required are still very high for the wind turbine generator system. Meanwhile, the availability of offshore PLTB is decreased by 60% due to the main cause of damage to some components in wind turbine systems. This study proposes the use of fault estimation methods of wind turbine system components in fault tolerant control (FTC) strategy. The error estimation method is build using the ℓ0 norm constraint optimization. The optimization formulation with ℓ0 norm constraint is derived by applying the compressed sensing technique so that the estimation of the bias error can be used to estimate the error of several components by a single observer. This answers the observability issues encountered in single observer use cases. The proposed implementation of observers with the FTC results in better response characteristics when compared to systems without FTC. Response characteristics on actuator errors of 0.3 – 1.3pu, system with observers resulting in a maximum undershoot value of 0.4-1% while systems without observers resulting in a maximum undershoot value of 6.2-26.4%. The characteristics of the response with the observer on sensor errors resulting 0.3-1.3pu resulting in value of 1.6-4%, 0% and 63.9- 70.7s. System without observers, with sensor errors of 0.3-1.3pu resulting in maximum undershoot, steady state error and settling time of 6.2-26.2%, 6.2-26.4%, and 0
Modeling Risk Factors for Total Paralysis of Stroke Patients in RSUD Dr. R. Sosodoro Djatikoesoemo Bojonegoro Using Binary Logistic Regression
Get PDFOne of the causes of death in Bojonegoro Regency is stroke. Stroke is a nervous system function disorder that occurs suddenly and is caused by circulatory disorders of the brain. From 2015 to March 2018, stroke has always been ranked first as the type of disease that most patients suffer in RSUD Dr. R. Sosodoro Djatikoesoemo Bojonegoro. Stroke can cause sufferers to experience limited ability to carry out daily activities (eating, dressing, defecating, bathing, and moving) because there are limbs that are paralyzed so it is difficult to move. Therefore, this study aims to describe the characteristics of stroke patients and to analyze the risk factors that cause stroke patients get totally paralyzed using binary logistic regression. The data used in the form of secondary data obtained from the results of medical records of stroke patients who were hospitalized at RSUD Dr. R. Sosodoro Djatikoesoemo Bojonegoro from January to March 2018. Based on the results of the analysis showed that the majority of stroke patients are over 55 years old and males also the risk factors that cause stroke patients geet totally paralyzed are the type of stroke and previous history of stroke
Monitoring and Analysis of Single Tube Temperature Distribution in Heat Exchanger Simulator Using TPA 81 Thermopile Array
Get PDFThe Energy and Environmental Engineering Laboratory had a heat exchanger simulator which was used to determine the temperature changes with respect to time due to air velocity. This simulator used tubes which were used to find out the temperature change with time. The working principle of this simulator was to monitor changes in temperature on the tube that had been preheated and then cooled using a fan contained in the simulator. This study performed temperature measurements using a TPA81 thermal array sensor. We chose this sensor because it could measure the temperature without touching the object and had 8 pixels for image measurement. This was because the process of reducing the temperature of the tube becomes purely caused by the fan and not from the outside environment. The results obtained from this study were visualization of temperature distribution using the Thermal Array TPA81 sensor, having a linearity value of 0.034%, a precision value of the instrument of 98.1%, an accuracy value of 0.285%, and error value of 0.154 (W/m2K). For the analysis of temperature distribution, it was concluded that the value of the temperature did not affect the value h, because the value of h (the coefficient of heat transfer convection) is distributed with time
Performance of Water Pump on Distribution and Transmission Process using Variable Speed Drive
Get PDFThe Pump is the vital component in the transmission of water from one unit to another or the distribution water from booster unit to customer. Water pumping has become ineffective due to incorrect installation of the installed pump not in accordance with the pre-installed piping. Investing in network development in the coming year is sometimes one of the reasons why pumps are installed improperly. Thus, high pressure pumps are sometimes installed at lower pipeline pressure. This condition usually does not only double between the pressure in the pipe and pump. Classically, pump output lines are usually coupled with valves (usually butterfly or rotary valves) to provide conditions that correspond to the pump's datasheet. Meanwhile, the classical concept will decrease the lifetime of pump, so the Variable Speed Drive (VSD) becomes the solution. TawangSari, SiwalanPanji, and KedungUling units are picture how VSD can fix kind of problem that faced in classical system. Worst energy use and decreased performance in classical system cause by wrong installation and limitation of supply power are solved by adapting frequency produced by VSD as it needed
Design and Development of Fuzzy-PID Controller for Four-Wheeled Mobile Robotic Stability: A Case Study on the Uphill Road
Get PDFDesign intelligent control to maximize the performance of the Four-Wheeled Mobile Robot (FWMR) in case of uphill road problems. The variation of slope angle and load variation on the uphill road is applied to know the performance of the automatic control system on FWMR. The research is divided into three two covering, system identification, design system and simulation testing. The Rotary speed control system response with fuzzy-PID control method has a good performance by anticipating various tilt angle 5o. The system can through uphill with loads 11N with a steady time and fast travel time. The best travel time in the 5o tilt angle condition is 2 seconds with a 4m circuit length. This research concludes that fuzzy-PID control can be implemented and increase the dynamic response of the FWMR effectively on the uphill road problems
Study Literature of Extraction Lipid Method from Microalgae Nannochloropsis sp
Get PDFBiodiesel is a promising alternative fuel obtained from plant oils and animal fats through the esterification process with alcohol. Lipid microalgae Nannochloropsis sp. can be used as raw material for the production of biodiesel or biofuel with oil content in the microalgae Nannochloropsis sp. as much as 21.3 - 32.7% so, it has the potential to be used as a raw material in making biodiesel. Biodiesel produced from microalgae biomass is the most suitable alternative fuel for the future and environmentally friendly fuel. In microalgae lipid extraction, Nannnochloropsis sp. using several process aids such as autoclave, microwave, and soxhlet. Different types of solvents are used to determine the% yield of lipids present in microalgae. Extraction was carried out to compare the extraction method using autoclave, microwave, and soxhlet to obtain the best method that produced the most substantial % lipid. An autoclave obtained the most abundant lipid yield with n-hexane solvent with a ratio of 3: 1 solvent and algal oil. Thus, this review describes the lipid extraction of the microalgae Nannochloropsis sp. with various extraction aids and different solvent types related to lipid production over the past few years