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"As an initial analysis,numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flowconditions and geometry can be adjusted easily to obtain results. Computationalfluid dynamics (CFD) methods, suchas the k-ε model, renormalizationgroup (RNG) k-ε model and reynolds stress model (RSM), are widely used toconduct research on differentobjects and conditions. Choosing the appropriate model helps produce and developconstant values.Modeling studies as appropriate, i.e., in the turbulent flow simulation in the windtunnel, isdone to get a more accurate result. This study was conducted by comparing the results ofthe simulation k-ε model, RNG k-ε model and RSM, which is validated by the testresults. The air had adensity of 1,205 kg/m3, a viscosity of 4×10-5 m2/sand a normal speed of 6 m/s. By comparing the simulation results of the k-ε model, RNG k-ε model and RSM, which isvalidated by the test results, the third turbulencemodel provided good results to predict the distribution of speedand pressure of the fluid flow in the wind tunnel. As for predicting theturbulent kinetic energy, turbulent dissipation rate and turbulent effectiveviscosity, the k-εmodel was effectivelyused with comparable results to the RSM models."

"As an initial analysis, numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flow conditions and geometry can be adjusted easily to obtain results. Computational fluid dynamics (CFD) methods, such as the k-? model, renormalization group (RNG) k-? model and reynolds stress model (RSM), are widely used to conduct research on different objects and conditions. Choosing the appropriate model helps produce and develop constant values. Modeling studies as appropriate, i.e., in the turbulent flow simulation in the wind tunnel, is done to get a more accurate result. This study was conducted by comparing the results of the simulation k-? model, RNG k-? model and RSM, which is validated by the test results. The air had a density of 1,205 kg/m3, a viscosity of 4×10-5 m2/s and a normal speed of 6 m/s. By comparing the simulation results of the k-? model, RNG k-? model and RSM, which is validated by the test results, the third turbulence model provided good results to predict the distribution of speed and pressure of the fluid flow in the wind tunnel. As for predicting the turbulent kinetic energy, turbulent dissipation rate and turbulent effective viscosity, the k-? model was effectively used with comparable results to the RSM models."

"The combination ofbaffled air flotation and a membrane system for the treatment of palm oil milleffluent (POME) was studied. The POME was obtained from a palm oil factory inPTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions,such as the hydraulic retention time and air flow rates, were varied to findthe optimum process. The air flotation process is able to reduce theconcentration of suspended solids and fats/ oils contained in the wastewater,which increases the performance of the membrane by reducing clogging. Theresults showed that this method was promising for POME treatment. The optimumorganic removal efficiency of the air flotation pretreatment was obtained atHRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequentlypassed through an anaerobic membrane system to achieve the highest removalefficiency treatment. The removal efficiency of chemical oxygen demand (COD),total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS),mixed liquor volatile suspended solids (MLVSS), and fats/oils after passingthrough the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%,respectively. The results also showed that the pH could be neutralized to 6.18,while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A highquality of effluent was obtained, which met the standards for POME effluent."

"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 ofthe poultry house, the root-mean-square error (RMSE) obtained for internal temperatures are 1.17oC, 0.68oC, and 0.46oC, respectively. Andthose data for relative humidity are 4.31%, 8.07%, and 53.54%, respectively."

"UKM memiliki peranan terhadap peningkatan produk domestik bruto (PDB) dan penyerapan tenaga kerja. pemerintah dan swasta diharapkan ikut memberikan perhatian dan inisiatif yang lebih dalam pengembangan UKM, sehingga UKM diharapkan mempunyai daya saing yang tinggi. penggunaan teknologi diharapkan dapat memberikan manfaat yang besar terhadap dunia bisnis yang kompetitif tersebut. salah satu jenis implementasi teknologi dalam hal meningkatkan persaingan bisnis dan penjualan produk adalah dengan menggunakan electronic commerce (e-commerce) untuk memasarkan berbagai macam produk atau jasa, baik dalam bentuk fisik maupun dalam bentuk digital. ukm di denpasar, bali memerlukan e-commerce yang mendukung aktifitas bisnisnya. untuk memenuhi keperluan tersebut diperlukan model e-commerce yang sesuai dengan UKM denpasar bali. Metode Structural Modeling (SEM) digunakan untuk membentuk e-commerce. faktor manajerial, faktor lingkungan dan kultur organisasi mempengaruhi perencanan strategi UKM terhadap pembangunan e-commerce. perencanaan strategi berpengaruh positif terhadap kinerja perusahaan. model ini diharapkan dapat memberikan pengetahuan tentang pengetahuan tentang e-commerce yang dapat membantu UKM untuk menjalankan aktivitas bisnisnya. model tersebut akad digunakan sebagai dasar untuk pengembangan aplikasi e-commerce pada penelitian selanjutnya."

"Many companies use self - service technology nowadays as a result of advances in technology. In the specific those companies replace personal services with self - service technology facilities. For instance, a bank can use automatic teller machine (ATM) instead of a bank teller inside the bank. The use of self - service technologies is aimed to fulfill the variety of consumers' needs. However, not many research focus on the impact of self - service technology on consumer satisfaction and loyalty. Therefore, the aim of this research is to test a model of the impact of self - service technology on consumer satisfaction and loyalty. This research replicated the model which was developed by Beatson et al (2006) and extend the model by adding a variable called consumer loyalty. Questionnaries were distributed to respondents by the drop - off / pick up method and total of 372 completed questionnaries were used in the analysis. The data was then analyzed using structural equation modeling. All research hypotheses were supported this paper also provides the implications for theoritical and managerial and offers directions of future research"

"The objective of this research was to study the effects of highly moist inlet air conditions such as temperature, relativehumidity, and frontal air velocity on the value of the Lewis number (Le) in the cooling and dehumidifying process of air. A finned tube cooling coil was testedunder ranges of temperature, relative humidity and frontal velocity. It wasfound that the Lewis number (Le) varied within the range of 0.92-1.62 and that the increase in inlet air relative humidity tends todecrease the Lewis number (Le). Based on theexperimental, a correlation for predicting the Lewis number (Le) was also established in this article. Thecorrelation has the mean absolute error (MAE) of 3.04% and covers 98.07% of the data where a discrepancy within ± 10%."

"Rice husk is one of themost abundant biomass wastes in Indonesia. One way to convert it into analternative source of energy is biomass gasification. This is a thermochemicalprocess which converts biomass feedstock into fuel gas or chemical feedstockgas (producer gas). The gasification type which is developed in this study isfixed bed downdraft type due to its low tar content and compatibility inmicroscale implementation. One major problem with the implemented biomassgasification reactor was ruggedness of the partial oxidation process due to theabsence of air in the reactor?s middle section, which consequently affected thepyrolysis zone. Several experiments were conducted previously using coconutshells and rice husks as solid feedstock, where an equivalence ratio (ER) of0.4 was obtained. Therefore, in order to optimize the pyrolysis zone, themodification conducted involves adding a circular air intake into the gasifier.Experiments were conducted in a pyrolysis temperature range of 300?700oCwith ER variation of 0.19, 0.24, 0.27 and 0.31. The results show that a goodquality producer gas is produced at an ER value of 0.24. This value shows apromising result because the ER value of biomass gasification standard is 0.25."

"A multi modelpredictive control and proportional-integral controller switching (MMPCPIS)approach is proposed to control a nonlinear distillation column. The study wasimplemented on a multivariable nonlinear distillation column (Column A). Thesetpoint tracking and disturbance rejection performances of the proposedMMPCPIS were evaluated and compared to a proportional-integral(PI) controller and the hybrid controller (HC). MMPCPIS developed to overcome theHC?s limitation when dealing with very large disturbance changes (50%). MMPCPIS provided improvements by 27% and 31%of the ISE (integral of square error) for feed flow rate andfeed composition disturbance changes, respectively, comparedwith the PI controller, and 24% and 54% of the ISE for feed flow rate and feedcomposition disturbancechange, respectively, compared with HC."