Journal articles: 'Process performance ratio'

1

Wang, Cheng, and Bing Yi Li. "CVT Ratio Adjusting Process Control." Advanced Materials Research 139-141 (October 2010): 1929–32. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.1929.

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Aiming at the shortcoming of the integral accumulation in the process of CVT ratio adjusting control, which is caused by the general PID control method, a new ratio adjusting control system based on the shift integral PID control method was designed. The theory of CVT ratio adjusting process and the enhanced control method were analized. The enhanced PID parameter tuning principle was presented. The test-bed of CVT ratio adjusting control was devised and adopted to do the CVT ratio tracing experiments. The experiments of step ratio from 0.45 to 1.45 and from 1.7 to 0.7 were made. The experimental results proved that the new ratio adjusting control system and the enhanced PID parameter tuning principle were valid, which made the real ratio trace the object ratio rapidly and steadily. The control performance of CVT ratio adjusting was improved.

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Mandal, Pathik. "Signal-to-noise ratio: a fundamental and broad process performance measure." Journal of Engineering Design 23, no. 12 (March 2012): 927–44. http://dx.doi.org/10.1080/09544828.2012.662274.

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Fröhlichová, M., D. Ivanišin, A. Mašlejová, R. Findorák, and J. Legemza. "Iron-Ore Sintering Process Optimization / Optymalizacja Procesu Aglomeracji Rudy Żelaza." Archives of Metallurgy and Materials 60, no. 4 (December 1, 2015): 2895–900. http://dx.doi.org/10.1515/amm-2015-0462.

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The work deals with examination of the influence of the ratio between iron ore concentrate and iron ore on quality of produced iron ore sinter. One of the possibilities to increase iron content in sinter is the modification of raw materials ratio, when iron ore materials are added into sintering mixture. If the ratio is in favor of iron ore sinter, iron content in resulting sintering mixture will be lower. If the ratio is in favor of iron ore concentrate and recycled materials, which is more finegrained, a proportion of a fraction under 0.5 mm will increase, charge permeability property will be reduced, sintering band performance will decrease and an occurrence of solid particulate matter in product of sintering process will rise. The sintering mixture permeability can be optimized by increase of fuel content in charge or increase of sinter charge moisture. A change in ratio between concentrate and iron ore has been experimentally studied. An influence of sintering mixture grain size composition, a charge grains shape on quality and phase composition on quality of the produced iron sinter has been studied.

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Zhang, Zhao Huan, Run Jun Sun, Mei Yu Chen, and Cheng Kun Liu. "Structure and Performance in the Compacting Process of Polyacrylonitrile Fiber." Advanced Materials Research 332-334 (September 2011): 437–40. http://dx.doi.org/10.4028/www.scientific.net/amr.332-334.437.

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As a key stage in wet spinning, compacting process served as a connection between spin and post treatment, it has significant influence on the performances of polyacrylonitrile (PAN) fiber. In this paper, the influences of temperature, time and tension on the compacting process and performance of fibers were studied. The test shows that the suitable compacting process condition is 110°C for 90s with a higher shrinkage ratio. With increasing shrinkage ratio, density and breaking elongation raise, but orientation and breaking strength decrease. To obtain better effect of compacting process, loss of orientation and breaking strength can hardly be avoided; it can be compensated by secondary draw in post process.

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Kilic, Arzu, Erkan Sahinkaya, and Ozer Cinar. "Kinetics of autotrophic denitrification process and the impact of sulphur/limestone ratio on the process performance." Environmental Technology 35, no. 22 (June 9, 2014): 2796–804. http://dx.doi.org/10.1080/09593330.2014.922127.

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Aoki, Nobuhiro, and Mitsuo Kawase. "Development of High-Performance Thermophilic Two-Phase Digestion Process." Water Science and Technology 23, no. 7-9 (April 1, 1991): 1147–56. http://dx.doi.org/10.2166/wst.1991.0566.

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Anaerobic digestion of anaerobic sewage sludge leads to the generation of methane gas and reduction of the sludge volume. Because conventional digestion requires a long time, the digestion facilities must be large. We studied decomposing volatile suspended solids (VSS) in sewage sludge, capacitating high acid generation rates and a high-speed methane evolution reactor to reduce retention time for anaerobic digestion. We also studied how to increase VSS reduction ratio by using bio-technology. The high-performance thermophilic two-phase digestion (HPTTD) process is proposed as a innovative digestion system which has high-rate reducing and high-ratio reduction of volatile suspended solids in sewage sludge. This thermophilic digestion process consists of sludge conditioning, acidification and methanation steps. In the sludge conditioning step, sewage sludge is conditioned with thermal treatment and dosed with a protolytic enzyme. In the next step, acidification, acid fermentation is carried out at 70°C; this temperature is higher than that of conventional fermentation (conventional thermophilic digestion process: 55°C). In the methanation step an anaerobic fixed-bed reactor is used. In the digestion experiments using excess sludge, we obtained a 30% higher VSS reduction ratio (78% at HPTTD process) than that of conventional mesophilic digestion,

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Mhilu, C. F. "Modeling Performance of High-Temperature Biomass Gasification Process." ISRN Chemical Engineering 2012 (November 1, 2012): 1–13. http://dx.doi.org/10.5402/2012/437186.

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Biomass utilization is becoming a subject of increasing interest as an alternative to clean fuel. A novel gasification process using highly preheated air gasifier using agricultural residue such as sugar bagasse, rice husks, and palm stem widely available in Tanzania is presented. The study examines, irreversibilities making the gasifier the least efficient unit in the gasification process employing a thermodynamic equilibrium model allowing predicting the main product gas composition CO, CO2, H2, and CH4. The derived model equations are computed using the MAPLE process simulation code in MATLAB. The gasification regime is investigated at temperatures ranging from 800 K to 1400 K and at equivalence ratio (ER) values between 0.3 and 0.4. The results obtained conform to the second law efficiency based on chemical exergy yielding maximum values for the types of biomass materials used. These results indicate that the application of preheated air has an effect on the increase of the chemical exergy efficiency of the product gas, hence reducing the level of irreversibility. Similarly, these results show that the combined efficiency based on physical and chemical exergy is low, suggesting that higher irreversibilities are encountered, since the exergy present in the form of physical exergy is utilized to heat the reactants. Such exergy losses can be minimized by altering the ratio of physical and chemical exergy in the syngas production.

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Xiao, Dong Ling, and Jian Ying Dai. "Application of Analytic Hierarchy Process (AHP) to Used Car Residue Ratio." Applied Mechanics and Materials 543-547 (March 2014): 228–31. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.228.

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Confirm the value of used car with improved replacement cost method, which involves one of the key parameters of the used car into residue ratio. Calculated by different mathematical model into residue ratio, reflected in the final pricing of used cars, there will be a larger gap. In this article, we will consider several factors to affect the value of a used car. Based on the MATLAB statistical software, performance factors and aggregative factors, analyzes and firm the weight of each performance index in calculating modified coefficients in accord with Analytic Hierarchy Process (AHP). Then modifies residue ratio of used motor vehicles with coefficients and firms the assess price. Finally, it was useful and effective that the improved replacement cost method was proved by some experiences.

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Guo, Ming Hui, and Jian Peng Hu. "The Fiberboard of Hot Pressing Process Optimization and Combination Performance Characterization." Applied Mechanics and Materials 44-47 (December 2010): 2278–82. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.2278.

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To pack a certain quality ratio ammonium lignosulfonate / urea as a filler into the natural wood fiber, Using flat pressure process fiberboard materials, Optimize the hot pressing technique that the filler is 20% (The quality ratio of lignosulfonate/ urea is 5: 3), slab moisture content is 13%, hot-pressing temperature is 190°C; hot-pressing time is 7 minutes, hot-pressing pressure is 2MPa and 1% paraffin emulsion. Verifying test results show that mechanical performance is stable and reliable process. Analyze the reactivity of fiberboard packing, fiber gathered, the microstructure of interface properties with the application of FTIR, XRD and ESEM and other modern instrument analysis technology.

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Su, J. L., and C. F. Ouyang. "Nutrient removal using a combined process with activated sludge and fixed biofilm." Water Science and Technology 34, no. 1-2 (July 1, 1996): 477–86. http://dx.doi.org/10.2166/wst.1996.0406.

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A new nutrient removal system combining activated sludge with fixed biofilm was developed in this work. Fully and partially submerged rotating biological contactors (RBC) were added in the anaerobic, anoxic and aerobic reactors, respectively. The pilot-scale plant was fed synthetic municipal wastewater with the different operating parameters (i.e., hydraulic retention time, return sludge ratio and mixed liquid recycle ratio) to evaluate its performance. High degree performances of nutrient removal were obtained in the experiments. The specific substrate utilization rates in each reactor were also conducted in this work. The kinetic behaviours presented in the combined process were similar to the performance in a single sludge system. The biokinetics of a single sludge system can also be applied to the system that combines biofilm and activated sludge.

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11

Fan, Yuhong. "Position adjusted turnover ratio and mutual fund performance." Studies in Economics and Finance 35, no. 1 (March 5, 2018): 65–80. http://dx.doi.org/10.1108/sef-03-2016-0075.

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Purpose The purpose of this study is to examine the impact of position adjusted turnover ratio on mutual fund performance. Design/methodology/approach The author calculates position adjusted turnover ratio in the same three steps as Edelen et al. (2013). Position adjusted turnover ratio is intended to be a trading cost proxy that captures both fund trading volume and per-trade costs. A metric of eight Morningstar performance measures is utilized. Findings Results show that funds with a higher position adjusted turnover ratio tend to have a lower risk-adjusted performance, such as indicated by both Sharpe and Sortino ratios, and even though these funds may have a higher annualized return. Research limitations/implications The sample selection process is subject to a survival bias. Also, this study utilizes Morningstar performance measures rather than the widely used factors models. Practical implications This study examines the impact of invisible costs from fund trading. These findings encourage fund managers to take strategic steps to reduce the overall invisible cost impact to improve fund performance. Originality/value Few studies have investigated fund trading cost measured by position adjusted turnover ratio and its impact on fund performance. Further, this study contributes to current literature by using eight Morningstar fund performance variables, which are practitioner-oriented and are accessible by investors.

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12

Ebrahimi, R. "Effect of Volume Ratio of Heat Rejection Process on Performance of an Atkinson Cycle." Acta Physica Polonica A 133, no. 1 (January 2018): 201–5. http://dx.doi.org/10.12693/aphyspola.133.201.

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13

Li, Weiqiang, Daulat D. Mamora, and Yamin Li. "Solvent-Type and -Ratio Impacts on Solvent-Aided SAGD Process." SPE Reservoir Evaluation & Engineering 14, no. 03 (May 18, 2011): 320–31. http://dx.doi.org/10.2118/130802-pa.

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Summary Coinjecting solvent with steam under a steam-assisted-gravity-drainage (SAGD) process to reduce the required steam for production has gained importance in recent years. An extensive 2D simulation study to better understand the drainage mechanism of steam-with-solvent coinjection in the SAGD process shows that the condensation time difference of solvent and steam results in different films of gas solvent, liquid solvent, and water along the fluid interface. There is an optimal solvent-type and -concentration-ratio range for a particular reservoir and operating condition. Coinjecting the solvent at low concentration ratios can take advantage of the solvent dilution effect without losing too much heat effect from steam. In addition, this study indicates coinjection of suitable solvent mixtures may lead to better performance than injection of pure solvent in the field.

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14

Kaiser, Sandra K., and Richard R. Dague. "The Temperature-Phased Anaerobic Biofilter Process." Water Science and Technology 29, no. 9 (May 1, 1994): 213–23. http://dx.doi.org/10.2166/wst.1994.0483.

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The “temperature-phased anaerobic biofilter” or TPAB process (U.S. Patent pending), is a new high-rate anaerobic treatment system that includes a thermophilic (56°C) biofilter connected in series with a mesophilic (35°C) biofilter providing for two-temperature, two-phase treatment. Three TPAB systems of different thermophilic:mesophilic reactor size ratios were operated at system HRTs of 24 hrs, 36 hrs, and 48 hrs to characterize performance and to determine if an optimum size ratio exists between the thermophilic and mesophilic phases. The three TPAB systems achieved SCOD reductions in excess of 97% and TCOD reductions in excess of 90% for a synthetic milk substrate over a range of system COD loadings from 2 g COD/L/day to 16 g COD/L/day. There was little difference in performance between the three TPAB systems based on COD reduction and methane production. The 1:7 ratio of thermophilic:mesophilic phase TPAB system performed as well as the 1:3 and 1:1 size ratio TPAB systems. In applications of the process, a relatively small thermophilic first-phase can be used without sacrificing overall two-phase system performance. The TPAB process is a promising new anaerobic treatment technology with the ability to achieve higher efficiencies of organic removals than is generally possible for single-stage anaerobic filter systems operated at equivalent HRTs and organic loadings.

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Ettouney, H., H. El-Dessouky, and F. Al-Juwayhel. "Performance of the once-through multistage flash desalination process." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 216, no. 3 (May 1, 2002): 229–41. http://dx.doi.org/10.1243/095765002320183559.

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The brine circulation multistage flash desalination process (MSF) dominates the thermal desalination market, while the once-through multistage flash desalination process (MSF-OT) remains to be found on a limited scale. This is because the MSF-OT process has no control on the temperature of the feed sea water. For non-equatorial regions, where the sea water temperature drops to 5 — 15°C during winter operation, the MSF-OT performance deteriorates unless the volume of the low-temperature stages is drastically increased to allow for reduction in the brine reject temperature to lower values. Another approach to solving this problem is to use the brine mixing (MSF-M) technique to control the feed sea water temperature. Irrespective of this, the MSF-OT process should be considered the optimum choice for large-scale thermal desalination in equatorial regions, where the sea water temperature remains constant throughout the year at 28°C. This study focuses on design and performance features of the MSF-OT process. Results are presented in terms of variations in the process thermal performance ratio, the specific heat transfer area and the conversion ratio as a function of the top brine temperature, the number of flashing stages and the feed sea water temperature. The performance of the MSF-OT process is identical to the MSF process as long as the feed sea water temperature remains above 25°C. Evaluation of the MSF-M system and comparison with the performance of the MSF and MSF-OT processes is presented.

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Aamir, Muhammad, Zarnish Mahmood, Aqsa Nisar, Amjad Farid, Syyed Adnan Raheel Shah, Mudassir Abbas, Muhammad Ismaeel, Tanveer Ahmed Khan, and Muhammad Waseem. "Performance Evaluation of Sustainable Soil Stabilization Process Using Waste Materials." Processes 7, no. 6 (June 18, 2019): 378. http://dx.doi.org/10.3390/pr7060378.

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The process of soil stabilization is a fundamental requirement before road infrastructure development is possible. Different binding materials have been used worldwide as soil stabilizers. In this study, water treatment waste (i.e., alum sludge (AS)) was used as a soil stabilizer. Alum sludge can work not only as a low-cost soil stabilizer but also can solve the problem of waste management at a large scale. Utilization of alum waste can be a sustainable solution and environmentally friendly exercise. Thus, in consideration of the pozzolanic properties of alum, it was applied as a binder, similar to cement or lime, to stabilize the soil with the addition of 2%, 4%, 6%, 8%, and 10% of dry soil by weight. To analyze the resulting improvement in soil strength, the California Bearing Ratio (CBR) test was conducted in addition to three other tests (i.e., particle size analysis, Atterberg’s limits test, and modified proctor test). The soil bearing ratio was significantly improved from 6.53% to 16.86% at the optimum level of an 8% addition of alum sludge. Furthermore, the artificial neural networks (ANNs) technique was applied to study the correlations between the CBR and the physical properties of soil, which showed that, at 8% optimum alum sludge, maximum dry density, optimum moisture content, and plasticity index were also at maximum levels. This study will help in providing an eco-friendly soil stabilization process as well as a waste management solution.

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Zhou, Shi Biao, An Guo Xiao, Yong Chen, Zhen Gan Chen, Ai Ping Hao, Yuan Dao Chen, and Xiao Bing Huang. "The Preparation and Performance of Gypsum-Based Composites." Applied Mechanics and Materials 310 (February 2013): 46–50. http://dx.doi.org/10.4028/www.scientific.net/amm.310.46.

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Gypsum-based composites was produced using gypsum power(cement), PVA, white latex and sawdust via pouring process. The influences of water/ cement ratio, PVA/ cement ratio and glue/ cement ratio on release time, density and impact strength of the gypsum-based composites were investigated through orthogonal experiment. The results showed that PVA strengthened obviously impact strength, and also delayed the s release time of the Gypsum-based composites. Sawdust as light filler reduced the composites density. Low content of white latex is beneficial to increase the impact strength, while high content of white latex is easy to form micelle in the gypsum crystallization process and is enclosed in crystals, which decreases the impact strength of composite materials.

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Santoso, Dana, and Arif Mahendra Besral. "SUPPLIER PERFORMANCE ASSESSMENT USING ANALYTICAL HIERARCHY PROCESS METHOD." SINERGI 22, no. 1 (February 28, 2018): 37. http://dx.doi.org/10.22441/sinergi.2018.1.007.

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This research was conducted in Hyundai Aluminium Co., Ltd. The company is a manufacturer and applicator for the job, especially aluminium curtain wall installation. Glass materials needed to form a curtain wall unit that these materials are not produced by Hyundai Aluminium Co., Ltd. To the researchers intend to determine the priority criteria, sub-criteria and consistency of thought or opinion of the respondents who are staff at Hyundai Aluminium Co., Ltd. in determining the glass supplier. In this study, the authors use the method of Analytical Hierarchy Process (AHP) to determine the priority of criteria, sub-criteria that compared global priority and will test the level of consistency of answers. The order of importance of criteria on the results of this research is Quality (.290), accuracy of delivery (0.279), price (0.238) and Service (0.193). Sequence global priority sub-criteria are H1 (0.174), K1 (0,138), D1 (0.114), K3 (0.096), H2 (0.063), K2 (0.056), L3 (0.034), D2 (0.025), L2 (0,023), L1 (0.006). Consistensi Value Ratio (CR) among criteria and sub-criteria inter smaller than 0.1 (CR, 0.1) which means that the answers of the respondents consistently.

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Kim, Kyoung Hoon, and Chul Ho Han. "Performance Analysis of Wet Compression Process under Critical Conditions of Water Injection." Applied Mechanics and Materials 229-231 (November 2012): 2541–45. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.2541.

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In wet compression process water is injected at an inlet of compressor and continuous cooling occurs due to evaporation of water droplets during the compression process of air, which can save the compression work and enhance the performance of gas turbine system. In this work, performance analysis of the wet compression process is carried out under the critical conditions of water injection which are defined as the maximum water injection which can be evaporated completely inside the compressor. For various ambient conditions the important variables of wet compression process such as water injection ratio, temperature-averaged polytropic coefficient, compressor outlet temperature, and compression work are estimated under the critical injection conditions. Parametric studies show that compression work decreases with ambient temperature, however, the reduction ratio of compression work relative to dry increases with ambient temperature.

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Lee, J. G., J. M. Hur, D. Chang, and T. H. Chung. "Performance characterization of anaerobic sequencing batch reactor process for digestion of night soil." Water Science and Technology 43, no. 1 (January 1, 2001): 27–34. http://dx.doi.org/10.2166/wst.2001.0007.

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Laboratory experiments were conducted to investigate the performance of an anaerobic sequencing batch reactor (ASBR) process for night soil treatment. Performances of the reactors were evaluated at an equivalent hydraulic retention time (HRT) of 10 days with an equivalent loading rate of 2.6 kgVS/m3/d (3.1 kgCOD/m3/day) at 35°C. Digestion of a night soil was possible using the ASBR at an HRT of 10 days in spite of high concentration of ammonia nitrogen and settleable solids. Solids were accumulated rapidly in the ASBRs, and their concentrations were 2.3∼2.4 times higher than that in a completely mixed control reactor. Remarkable increases in gas production were observed in the ASBRs compared with the control reactor. Average increases in equivalent daily gas production from the ASBRs were 205∼220% compared with that from the control run. The ASBR with reaction period/thickening period ratio (R/T ratio) of 1 showed a little higher gas production and organic removal efficiency than that with R/T ratio of 3. Volatile solids removals based on supernatant of the ASBRs were 12∼14% higher than that of the control reactor. Thus, the ASBR was a stable and effective process for the treatment of night soil having high concentration of settleable organics and ammonia nitrogen.

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Park, Jiyeong, Seok-Hong Min, Won-Hee Lee, No-Suk Park, Hyung-Soo Kim, and Jong-Oh Kim. "Properties and filtration performance of microporous metal membranes fabricated by rolling process." Journal of Water Reuse and Desalination 7, no. 1 (March 3, 2016): 11–15. http://dx.doi.org/10.2166/wrd.2016.000.

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We evaluated the filtration performance of microporous metal membranes fabricated by the rolling process. Metal wire meshes were rolled with thickness reduction ratios of 10, 20, and 30%. The pore size of the metal wire mesh membrane decreased with increasing rolling ratio, whereas the removal efficiency of the suspended solids and turbidity showed a very slight increase compared to that of an unrolled mesh membrane. The metal powder was dispersed on the surface of the rolled metal wire mesh membrane and bound with polyvinyl alcohol, then dried at 100°C for 1 h, and finally sintered at 1,000°C for 3 h. The mean pore size, suspended solids, and turbidity of the metal powder membrane at a rolling ratio of 30% were approximately 0.7 μm, 84% and 83%, respectively. Therefore, microporous metal membranes successfully fabricated by the rolling process were also sufficiently permeable filters.

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Yan, Jun Hai, and Xiao Song Zhang. "The Performance Analysis of Single Water Droplet Evaporative Supercooled Process for Ice Slurry Production." Applied Mechanics and Materials 325-326 (June 2013): 1422–26. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.1422.

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To analyze evaporative supercooled process of single water droplet in the air with low temperature and low humidity ratio, a mathematical model was constructed to simulate the evaporative process of single water droplet. The droplet temperature during its evaporation process and the influence of different initial droplet diameter, initial water temperature, air temperature and air humidity ratio were analyzed. The evaporative process of droplet in supercooled stage was simulated through the mathematical model, results from modeling basically tallies with the experiment. The numerical results show that lower initial temperature of water droplet can lessen the supercooled time of reaching steady state evaporation stage. Additionally it can not only lessen the supercooled time but also acquire lower supercooled temperature of water droplet by reducing air humidity ratio or lowering air temperature. Furthermore, the smaller initial diameter of water droplet is, the shorter supercooled time of reaching steady state evaporation stage becomes.

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Wang, Wen Bin, Dao Yuan Liu, and Yu Qin Yao. "Study of PID Control Algorithm Based on the Critical Ratio Method." Applied Mechanics and Materials 494-495 (February 2014): 1246–48. http://dx.doi.org/10.4028/www.scientific.net/amm.494-495.1246.

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PID control is one of the earliest control strategy and till has the most widely use in the industrial process at the present. The PID parameter tuning and optimizing decide what the control performance of the control system can achieve. PID parameter tuning is the core content in control system design. In this paper, aiming at the complexity of PID parameter tuning process, the critical ratio method was optimized and propose a simple and effective method of tuning PID parameters. By simulation, this method turn out to be simple and effective, good real-time performance.

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YING, FUQIANG, LINHANG ZHOU, and LI WANG. "ANALYSIS OF THE STRUCTURAL PERFORMANCE AND STRETCHING PROCESS OF THE HONEYCOMB PAPER CORE." Journal of Advanced Manufacturing Systems 07, no. 01 (June 2008): 187–92. http://dx.doi.org/10.1142/s0219686708001346.

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Honeycomb paper core stretching is an important process in paper core manufacture because the performance and the quality of paperboard are greatly enhanced when the honeycomb hole is stretched to a regular hexagon structure. In view of the above, first the finite element method is used to compare the mechanical performances of honeycomb paperboards of different aperture ratios, and the aperture ratio, which has an important influence on the performance of the honeycomb paper, is explained. Next, a paper core stretching simulation is carried out by means of the dynamic software; thus the variation trend of the stretching force, the stretching speed, and the lateral shrinkage needed in paper core manufacture of different specifications can be obtained. This research can provide useful instruction in the actual manufacture of honeycomb paper core.

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Yang, Ruomiao, Xiaoxia Sun, Zhentao Liu, Yu Zhang, and Jiahong Fu. "A Numerical Analysis of the Effects of Equivalence Ratio Measurement Accuracy on the Engine Efficiency and Emissions at Varied Compression Ratios." Processes 9, no. 8 (August 16, 2021): 1413. http://dx.doi.org/10.3390/pr9081413.

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Increasingly stringent regulations to reduce vehicle emissions have made it important to study emission mitigation strategies. Highly accurate control of the air-fuel ratio is an effective way to reduce emissions. However, a less accurate sensor can lead to reduced engine stability and greater variability in engine efficiency and emissions. Additionally, internal combustion engines (ICE) are moving toward higher compression ratios to achieve higher thermal efficiency and alleviate the energy crisis. The objective of this investigation was to analyze the significance of the accuracy of air-fuel ratio measurements at different compression ratios. In this study, a calibrated 1D CFD model was used to analyze the performance and emissions at different compression ratios. The results showed that carbon monoxide (CO) and nitrogen oxides (NOx) were sensitive to the equivalence ratio regardless of the compression ratio. With a slight change in the equivalence ratio, a high compression ratio had little effect on the change in engine performance and emissions. Moreover, with the same air-fuel ratio, an excessively high compression ratio (CR = 12) might result in knocking phenomenon, which increases the fluctuation of the engine output parameters and reduces engine stability. Overall, for precise control of combustion and thermal efficiency improvement, it is recommended that the measurement accuracy of the equivalence ratio is higher than 1% and the recommended value of the compression ratio are roughly 11.

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Kadarwati, Sri, and Sri Wahyuni. "Characterization and Performance Test of Palm Oil Based Bio-Fuel Produced Via Ni/Zeolite-Catalyzed Cracking Process." International Journal of Renewable Energy Development 4, no. 1 (February 15, 2015): 32–38. http://dx.doi.org/10.14710/ijred.4.1.32-38.

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Catalytic cracking process of palm oil into bio-fuel using Ni/zeolite catalysts (2-10% wt. Ni) at various reaction temperatures (400-500oC) in a flow-fixed bed reactor system has been carried out. Palm oil was pre-treated to produce methyl ester of palm oil as feedstock in the catalytic cracking reactions. The Ni/zeolite catalysts were prepared by wetness impregnation method using Ni(NO3)2.6H2O as the precursor. The products were collected and analysed using GC, GC-MS, and calorimeter. The effects of process temperatures and Ni content in Ni/zeolite have been studied. The results showed that Ni-2/zeolite could give a yield of 99.0% at 500oC but only produced gasoline fraction of 18.35%. The physical properties of bio-fuel produced in this condition in terms of density, viscosity, flash point, and specific gravity were less than but similar to commercial fuel. The results of performance test in a 4-strike engine showed that the mixture of commercial gasoline (petrol) and bio-fuel with a ratio of 9:1 gave similar performance to fossil-based gasoline with much lower CO and O2 emissions and more efficient combustion

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Toda, Hiro Y. "Finite Sample Performance of Likelihood Ratio Tests for Cointegrating Ranks in Vector Autoregressions." Econometric Theory 11, no. 5 (October 1995): 1015–32. http://dx.doi.org/10.1017/s0266466600009956.

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This paper investigates through Monte Carlo simulation the finite sample properties of likelihood ratio tests for cointegrating ranks that were proposed by Johansen (1991, Econometrica 59, 1551–1580). We transform the model into a canonical form so that the experiment is well controlled without loss of generality and then conduct a comprehensive simulation study. As expected, the test performance is very sensitive to the value of the stationary root(s) of the process. We also find that the test performance depends crucially on the correlation between the innovations that drive the stationary and the nonstationary components of the process. We conclude that 100 observations are not sufficient to ensure reasonably good performance uniformly over the values of the nuisance parameters that affect the distributions of the test statistics.

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Wang, Lei, Huai Chen, Ting Ting Liu, Jun Yang Ji, and Xue Hui Gan. "Study on the Composite Spinning Co-Extrusion Process of the Tri-Component." Advanced Materials Research 661 (February 2013): 81–86. http://dx.doi.org/10.4028/www.scientific.net/amr.661.81.

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In the molding process of the tri-component composite spinning, the flow control of each component plays a significant impact on extrusion swell. This paper simulates the extrusion swell of the tri-component fiber in different flow ratio of different components based on Polyflow fluid dynamics simulation software, and measures the extrusion swell ratio of the tri-component fiber in different flow ratio of different components through the experiment. Simulation and experimental results show that by adjusting the melt flow ratio of the various components, we can obtain the desired extrusion swell ratio, which can improve the performance of the tri-component fiber.

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Shodhan, K., and I. Wei. "Effects of mixing on chloramination process." Water Supply 10, no. 4 (September 1, 2010): 629–37. http://dx.doi.org/10.2166/ws.2010.170.

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According to a recent study more than 90 percent of water treatment plants utilizing chloramination for distribution system residuals indicate a certain level of dissatisfaction toward the process performance. One factor that may lead to such dissatisfaction is the inadequacy of mixing when ammonia is added to chlorinated water. If mixing is not instantaneous and uniform, the actual chlorine to ammonia nitrogen molar ratio will become variable at a micro-level, even though the overall ratio at the macro-level is close to the desired 1:1 ratio. Because of the non-uniform mixing, certain portions of the mixture might have a molar ratio exceeding the stoichiometric ratio of 1:1. In such instances, certain unintended reactions (e.g. breakpoint type of chlorine chemistry) can occur. This will lead to the resultant monochloramine concentration being significantly less than the stoichiometric concentration, based upon the calculation using the overall molar ratio. Other factors, such as pH variation in the micro environment, could also affect the final chemical composition of the chloramination process. In this study, the effect of mixing was studied by conducting breakpoint chlorination experiments under different levels of mixing, represented by the average velocity gradient, G in s−1. A unique way of plotting breakpoint chlorination curve was utilized to analyze the data, which allowed a clear delineation if the monochloramine formation was according to the stoichiometry. A quantitative comparison between experimental data and stoichiometry can clearly indicate the impact of non-uniform mixing. The experimental data showed that as the G value increased from 35 to 500 s−1, the monochloramine formation increased from 75 to 87 percent of the stoichiometric value. The location of the breakpoint, correspondingly, increased from a molar ratio of 1.25 to 1.75. Comparison of 40 s−1 (50 rpm) and 300 s−1 (200 rpm) experimental data was conducted and a breakpoint curve was plotted imposing one over the other. It has been observed from previous literature that in ideal conditions, breakpoint occurs at chlorine to ammonia nitrogen molar ratio of 1.5:1, and the peak of monochloramine is expected at a molar ratio of 1:1. Hence, breakpoint curve was plotted at mixing speed of 50 and 200 rpm, indicating free chlorine, monochloramine, dichloramine, trichloramine, and total chlorine concentration at contact time of 45 minutes. Few studies were found in literature on mixing effects in chloramination. Data from a previous study was re-analyzed and compared with the current study, and a similar trend was observed. In another case study, the design G value for a modern water treatment plant in metropolitan Boston was found to be 800 s−1, which was higher than the maximum G value used in this study (500 s−1), and is likely to be more than sufficient. In conclusion, when chlorine and ammonia are combined to produce monochloramine, the degree of mixing indeed has significant impact on the performance of the chloramination process, and therefore must be a critical consideration in its design and operation.

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Guan, Bowen, Jun Liu, Xiaohua Liu, Tao Zhang, Liangliang Chen, and Xiaoyang Chen. "Performance investigation of a novel hybrid deep-dehumidification process using liquid desiccant." E3S Web of Conferences 111 (2019): 01047. http://dx.doi.org/10.1051/e3sconf/201911101047.

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As one of the essential dehumidification ways, liquid desiccant air conditioning system has developed quickly in recent years, especially in the deep dehumidification field. A novel hybrid deep- dehumidification system using liquid desiccant driven by heat pump is proposed in this study to simplify the arrangement of air ducts and guarantee a competitive energy efficiency. In the proposed process, the regenerator, condensing dehumidifier and liquid dehumidifier are cascaded, and the process air flow through them sequentially. Heat pump cycle is utilized in the system, where the cooling capacity of evaporator is used to cool the liquid desiccant in dehumidifier, and the heating capacity of condenser is used for desiccant regeneration. The humidity ratio of the supplied air is as low as 2.6 g/kg. No extra regeneration air or corresponding air duct are needed in the proposed process, which obviously simplifies the layout of the system. Performance of the proposed system is then analysed by numerical results. It’s indicated 17.5~29.2% energy is saved compared with the conventional deep dehumidification process with two-stage heat pump, with the outlet humidity ratio of 2.6 g/kg.

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Hu, Fang, and Jun Fen Sun. "Performance and Morphology of PVDF/PEG-POSS Hybrid Membrane." Advanced Materials Research 1096 (April 2015): 446–49. http://dx.doi.org/10.4028/www.scientific.net/amr.1096.446.

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Polyvinylidene fluoride (PVDF)/PEG-POSS hybrid membrane was prepared by immersion phase separation process. The hybrid membranes were characterized by pure water flux, retention ratio to BSA, contact angle, shrinkage ratio and scanning electron microscopy (SEM). The hydrophilicity of the membrane was improved. The contact angles decreases from 82.2°to 76.3°. The shrinkage ratio decreases and the pure water flux increased when 1.0% POSS was used.Keywords: polyvinylidene fluoride (PVDF); PEG-POSS; hybrid membrane; hydrophilicity

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Amrina, Uly, and Alfa Firdaus. "THE SELECTION OF PRODUCTIVITY KEY PERFORMANCE INDICATORS FOR CAR MANUFACTURING COMPANIES USING INTEGRATED PERFORMANCE MEASUREMENT SYSTEM." SINERGI 22, no. 2 (June 27, 2018): 101. http://dx.doi.org/10.22441/sinergi.2018.2.005.

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The increase in car market 17% in 2020, and ASEAN Free Trade policy only 5% for imported products, cause tightened competition in the automotive market. Car manufacturing companies face problems in selecting their performance indicators related to competitive challenges. The purpose of this research is to develop productivity key performance indicators in car manufacturing that conform to stakeholder requirements as a strategy to win the market. The conditions are manifested in a mapping of manufacturing symbols using the Integrated Performance Measurement System (IPMS) method. That manufacturing productivity indicators will become the focus of the top management to be controlled. There are four stages to go through, starting with the identification of stakeholder requirement, which produces six criteria and 12 stakeholder requirements and mapped into 16 goals and 24 key performance indicator (KPI). The second stage is benchmarking, and preparation of KPI hierarchy and the third stage is the description of each KPI in the form of KPI specification table. The fourth stage is the weighting of the six main criteria that result in 3 priority criteria which must be reported monthly between the manufacturing division (painting), finance and administration. Those are employee safety, manufacturing process effectiveness (painting) and waste elimination activities. The priority is obtained based on questionnaires answered by ten stakeholders (experts) processed with Analytical Hierarchy Process (AHP) approach and has been tested consistency in the number 0.09. These three criteria are described in 15 KPIs: performance rate, availability rate, quality rate, trained operator ratio, training value ratio> 80, delay ratio, attendance ratio, downtime losses, setup and adjustment losses, idle time, defect losses, yield losses, manpower efficiency, environmental impact and work accident ratio.

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LOBOS, J., C. WISNIEWSKI, M. HERAN, and A. GRASMICK. "Sequencing versus continuous membrane bioreactors: Effect of substrate to biomass ratio (F/M) on process performance." Journal of Membrane Science 317, no. 1-2 (June 5, 2008): 71–77. http://dx.doi.org/10.1016/j.memsci.2007.08.041.

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Zhang, Xiaojing, Dong Li, Yuhai Liang, and Jie Zhang. "Reactor performance and microbial characteristics of CANON process with step-wise increasing of C/N ratio." Environmental Technology 37, no. 3 (August 21, 2015): 407–14. http://dx.doi.org/10.1080/09593330.2015.1070921.

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Feng, Suping, Nannan Zhang, Hanchao Liu, Xiaolin Du, Yongli Liu, and Hai Lin. "The effect of COD/N ratio on process performance and membrane fouling in a submerged bioreactor." Desalination 285 (January 2012): 232–38. http://dx.doi.org/10.1016/j.desal.2011.10.008.

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Jiang, Xingren, Ning Yang, and Rijie Wang. "Effect of Aspect Ratio on the Mixing Performance in the Kenics Static Mixer." Processes 9, no. 3 (March 5, 2021): 464. http://dx.doi.org/10.3390/pr9030464.

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Continuous manufacturing has received increasing interest because of the advantages of intrinsic safety and enhanced mass transfer in the pharmaceutical industry. However, the difficulty for scale-up has limited the application of continuous manufacturing for a long time. Recently, the tubular flow reactor equipped with the Kenics static mixer appears to be a solution for the continuous process scale-up. Although many influence factors on the mixing performance in the Kenics static mixer have been investigated, little research has been carried out on the aspect ratio. In this study, we used the coefficient of variation as the mixing evaluation index to investigate the effect of the aspect ratio (0.2–2) on the Kenics static mixer’s mixing performance. The results indicate that a low aspect ratio helps obtain a shorter mixing time and mixer length. This study suggests that adjusting the aspect ratio of the Kenics static mixer can be a new strategy for the scale-up of a continuous process in the pharmaceutical industry.

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Ong, Y. H., A. S. M. Chua, B. P. Lee, and G. C. Ngoh. "Long-term performance evaluation of EBPR process in tropical climate: start-up, process stability, and the effect of operational pH and influent C:P ratio." Water Science and Technology 67, no. 2 (January 1, 2013): 340–46. http://dx.doi.org/10.2166/wst.2012.552.

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To date, little information is known about the operation of the enhanced biological phosphorus removal (EBPR) process in tropical climates. Along with the global concerns on nutrient pollution and the increasing array of local regulatory requirements, the applicability and compliance accountability of the EBPR process for sewage treatment in tropical climates is being evaluated. A sequencing batch reactor (SBR) inoculated with seed sludge from a conventional activated sludge (CAS) process was successfully acclimatized to EBPR conditions at 28 °C after 13 days' operation. Enrichment of Candidatus Accumulibacter phosphatis in the SBR was confirmed through fluorescence in situ hybridization (FISH). The effects of operational pH and influent C:P ratio on EBPR were then investigated. At pH 7 or pH 8, phosphorus removal rates of the EBPR processes were relatively higher when operated at C:P ratio of 3 than C:P ratio of 10, with 0.019–0.020 and 0.011–0.012 g-P/g-MLVSS•day respectively. One-year operation of the 28 °C EBPR process at C:P ratio of 3 and pH 8 demonstrated stable phosphorus removal rate of 0.020 ± 0.003 g-P/g-MLVSS•day, corresponding to effluent with phosphorus concentration <0.5 mg/L. This study provides the first evidence on good EBPR activity at relatively high temperature, indicating its applicability in a tropical climate.

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Rizlan, Zulkhairi, and Othman Mamat. "Process Parameters Optimization of Silica Sand Nanoparticles Production Using Low Speed Ball Milling Method." Chinese Journal of Engineering 2014 (February 26, 2014): 1–4. http://dx.doi.org/10.1155/2014/802459.

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Experiments are designed using Taguchi method to find the optimum parameters for silica sand nanoparticles production using low speed ball milling. Orthogonal array and signal-to-noise ratio are applied to study performance characteristics of machining parameters which are the ball to powder weight ratio, volume of milling jar, and rotation speed. Results obtained from signal-to-noise ratio analysis showed that ball to powder weight ratio is the most influential parameter.

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Chen, Xue Wen, Ze Hu Liu, and Jing Li Zhang. "Robust Optimization for Tube Bending Process Based on Finite Element Method." Key Engineering Materials 531-532 (December 2012): 746–50. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.746.

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The main causes of performance variation in tube bending process are variations in the mechanical properties of material, initial tube thickness, coefficient of friction and other forming process parameters. In order to control this performance variation and to optimize the tube bending process parameters, a robust design method is proposed in this paper for the tube bending process, based on the finite element method and the Taguchi method. During the robust design process, the finite element analysis is incorporated to simulate the tube bending process and calculate the objective function value, the orthogonal design method is selected to arrange the simulation experiments and calculate the S/N ratio. Finally, a case study for the tube bending process is implemented. With the objective to control tube crack (reduce the maximum thinning ratio) and its variation, the robust design mathematical model is established. The optimal design parameters are obtained and the maximum thinning ratio has been reduced and its variation has been controlled.

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Jin, Dan, Zejun Lang, and Wu Yao. "Analysis of Early Performance of Cement Paste by Low Field NMR." Applied Sciences 9, no. 5 (March 2, 2019): 896. http://dx.doi.org/10.3390/app9050896.

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The change of the evaporable water content in the early hydration process of cement paste with different water-to-cement ratios was monitored by low field nuclear magnetic resonance (LF-NMR) relaxometry. The hydration degree and gel/space ratio were accordingly calculated and analyzed. The test results show that the first derivative curves of the transverse magnetization are in good agreement with the known five stages of cement hydration process at an early age. The initial and final setting times of the cement paste are closely related to the times the gel/space ratio reaches a fixed value. The early compressive strength of the hardened cement paste exhibits a power function relationship with the gel/space ratio.

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Szűcs, B. Rózsáné, G. L. Szántó, M. Simon, and Gy Füleky. "Process performance of dry, batch anaerobic digestion of sewage sludge: methanogenic seed mixtures." Water Science and Technology 66, no. 2 (July 1, 2012): 445–50. http://dx.doi.org/10.2166/wst.2012.223.

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A dry, batch anaerobic digestion (DBAD) process was tested on two sewage sludge types with different methanogenic seed fractions under laboratory conditions. The aim was to indicate optimal sludge:seed mixing ratios and analyse process performance based on degradation rate and reactor-specific methane production. The attained results were compared with the performance of a liquid-state, laboratory-scale stirred reactor (SR). A mixing ratio of at least 1:1.25 (sludge:seed) yielded processes free from significant inhibitions. Further seeding increments resulted in slightly better performances, but much lower sludge fractions treated in the reactors. Compared with the SR process, the DBAD reactors produced comparable degradation rates albeit in a significantly longer process and with somewhat lower reactor-specific methane production rates. These findings indicate that the DBAD method may provide a viable alternative to liquid-state processes if sludge drying is already applied and reactor volume requirements are of importance.

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Ma, Feng, Jiasheng Dai, Zhen Fu, Jenny Liu, Wenhao Dong, and Zhen Huang. "A New Type of Crumb Rubber Asphalt Mixture: A Dry Process Design and Performance Evaluation." Applied Sciences 10, no. 1 (January 3, 2020): 372. http://dx.doi.org/10.3390/app10010372.

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To obtain a crumb rubber asphalt mixture with excellent performance, this study combined trans-polyoctenamer rubber (TOR), crumb rubber, and other additives to establish a new type of crumb rubber (CRT). The objective of this study was to design and evaluate the road performance of the new type of crumb rubber asphalt mixture (CRTAM) with a skeleton dense texture through a dry process. First, the skeleton intrusion compact volume method was used to optimize the grading of coarse and fine aggregates, and the design of the CRTAM gradation was carried out through the same and unequal volume replacement grading method. Then, three types of road performance were analyzed: high-temperature stability, low-temperature crack resistance, and water stability. The results showed that 2% and 2.5% CRT met a low-temperature index with equal volume substitution, and the six gradations obtained by unequal volume replacement with 2% CRT complied with the requirements of a skeleton dense texture. When the substitution ratio was 1.5 and 0.5, the high-temperature performance was better. In addition, when the substitution ratio was 0.5, the flexural strain energy density was the highest and the low-temperature performance was the best. Including considerations of economic benefits, it is recommended that the CRT content be 2% and the substitution ratio be 0.5.

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Orssatto, Fábio, Marcio A. Vilas Boas, Ricardo Nagamine, and Miguel A. Uribe-Opazo. "Shewhart's control charts and process capability ratio applied to a sewage treatment station." Engenharia Agrícola 34, no. 4 (August 2014): 770–79. http://dx.doi.org/10.1590/s0100-69162014000400016.

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The current study used statistical methods of quality control to evaluate the performance of a sewage treatment station. The concerned station is located in Cascavel city, Paraná State. The evaluated parameters were hydrogenionic potential, settleable solids, total suspended solids, chemical oxygen demand and biochemical oxygen demand in five days. Statistical analysis was performed through Shewhart control charts and process capability ratio. According to Shewhart charts, only the BOD(5.20) variable was under statistical control. Through capability ratios, we observed that except for pH the sewage treatment station is not capable to produce effluents under characteristics that fulfill specifications or standard launching required by environmental legislation.

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Han, Seho, Kisong Lee, Hyun-Ho Choi, and Howon Lee. "BiPAD: Binomial Point Process Based Energy-Aware Data Dissemination in Opportunistic D2D Networks." Energies 11, no. 8 (August 9, 2018): 2073. http://dx.doi.org/10.3390/en11082073.

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In opportunistic device-to-device (D2D) networks, the epidemic routing protocol can be used to optimize the message delivery ratio. However, it has the disadvantage that it causes excessive coverage overlaps and wastes energy in message transmissions because devices are more likely to receive duplicates from neighbors. We therefore propose an efficient data dissemination algorithm that can reduce undesired transmission overlap with little performance degradation in the message delivery ratio. The proposed algorithm allows devices further away than the k-th furthest distance from the source device to forward a message to their neighbors. These relay devices are determined by analysis based on a binomial point process (BPP). Using a set of intensive simulations, we present the resulting network performances with respect to the total number of received messages, the forwarding efficiency and the actual number of relays. In particular, we find the optimal number of relays to achieve almost the same message delivery ratio as the epidemic routing protocol for a given network deployment. Furthermore, the proposed algorithm can achieve almost the same message delivery ratio as the epidemic routing protocol while improving the forwarding efficiency by over 103% when k≥10.

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Guo, Xiaoyu, Yajing Mao, Lizhai Pei, and Chuangang Fan. "Mechanical Performance of the Phosphogypsum Baking-free Bricks." Current Materials Science 14, no. 2 (August 12, 2021): 131–40. http://dx.doi.org/10.2174/2666145414666210203115332.

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Background: A large amount of phosphogypsum occupies the land and causes environmental pollution. It is of great research significance and urgency to the utilization of the phosphogypsum. Methods: The influence of the ratio of the cementing materials and phosphogypsum (C/P ratio) on the compressive strength, water absorption, softening coefficient and freeze-thaw stability of the phosphogypsum baking-free bricks was investigated. The consolidation process of the phosphogypsum baking-free bricks was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results: XRD patterns show that the phosphogypsum baking-free bricks curved for 28 d are mainly composed of monoclinic CaSO4·2H2Oand hexagonal Ca6Al2(SO4)3(OH)12·26H2O (Aft) phases. SEM observation shows that the phosphogypsum bricks consist of Aft nanorods and irregular microscale particles. The softening coefficient, water-resistant performance and freezethaw stability of the phosphogypsum baking-free bricks remarkably decrease with decreasing the C/P ratio. 28 d compressive strength decreases from 26.42 MPa to 15.58 MPa with the change of the C/P ratio from 1:1 to 1:2.5. The optimal ratio of the cementing materials and phosphogymsum is 1:1. The phosphogypsum baking-free bricks exhibit good stability after 18 freeze-thaw cycles. Conclusion: Phosphogypsum baking-free bricks were prepared by natural curing process using phosphogypsum as the raw materials, cement, slag, fly ash and silica fume as the cementing materials. The phosphogypsum baking-free bricks exhibit great application in the field of building materials.

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Zubrowska-Sudol, M., J. Yang, J. Trela, and E. Plaza. "Evaluation of deammonification process performance at different aeration strategies." Water Science and Technology 63, no. 6 (March 1, 2011): 1168–76. http://dx.doi.org/10.2166/wst.2011.356.

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In a deammonification process applied in the moving bed biofilm reactor (MBBR) oxygen is a crucial parameter for the process performance and efficiency. The objective of this study was to investigate different aeration strategies, characterised by the ratio between non-aerated and aerated phase times (R) and dissolved oxygen concentrations (DO). The series of batch tests were conducted with variable DO concentrations (2, 3, 4 mg L−1) and R values (0-continuous aeration; 1/3, 1, 3-intermittent aeration) but with the same initial ammonium concentration, volume of the moving bed and temperature. It was found that the impact of DO on deammonification was dependent on the R value. At R=0 and R=1/3, an increase of DO caused a significant increase in nitrogen removal rate, whereas for R=1 and R=3 similar rates of the process were observed irrespectively of the DO. The highest nitrogen removal rate of 3.33 g N m−2 d−1 (efficiency equal to 69.5%) was obtained at R=1/3 and DO=4 mg L−1. Significantly lower nitrogen removal rates (1.17–1.58 g N m−2 d−1) were observed at R=1 and R=3 for each examined DO. It was a consequence reduced aerated phase duration times and lesser amounts of residual nitrite in non-aerated phases as compared to R=1/3.

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Ren, Lian Hai. "Hydrothermal Process for Restaurant Garbage." Applied Mechanics and Materials 295-298 (February 2013): 1687–95. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.1687.

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In order to optimized the process parameters of Hydrothermal Process for Restaurant Garbage, a set of U24(63) uniform design trial tests were implemented. The results showed that the optimal condition for preparing feed from restaurant garbage is being heated for 80 minutes at 120 °C with water addition ratio on 30%. Additionally, hydrothermal treatment can kill bacteria thoroughly and affect the dewaterablity of the garbage markedly. Furthermore, hydrothermal process improvs the de-oil performance of the garbage, and the optimal conditions for de-oil is being heated for 80 minutes at 160 °C.

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Wasiwitono, Unggul, Agus Sigit Pramono, I. Nyoman Sutantra, and Yunarko Triwinarno. "Influence of Spring Ratio on Variable Stiffness and Damping Suspension System Performance." Applied Mechanics and Materials 836 (June 2016): 31–36. http://dx.doi.org/10.4028/www.scientific.net/amm.836.31.

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The variable stiffness and damping (VSVD) suspension system offers an interesting option to improve driver comfort in an energy efficient way. The aim of this study is to analyze the influence of the spring ratio on the VSVD. The realization of the VSVD is obtained by the application of variable damping with magnetorheological (MR) damper. In this study, the nonlinear damping force characteristic of the MR damper is modeled with the Bouc-Wen model and the road disturbance is modeled by a stationary random process with road displacement power spectral density. It is shown from simulation that VSVD has a potential benefit in improving performance of vehicle suspension.

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Li, Li. "The GLR Chart for Poisson Process with Individual Observations." Advanced Materials Research 542-543 (June 2012): 42–46. http://dx.doi.org/10.4028/www.scientific.net/amr.542-543.42.

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A GLR (generalized likelihood ratio) chart for Poisson distributed process with individual observations is proposed and the design procedure of the GLR chart is discussed. The performance of the GLR charts is compared to the exponentially weighted moving average (EWMA) chart and the GWMA chart. The numerical experiments show that the GLR chart has comparable performance as the other two charts. However, the GLR chart is much easier to design and implement since there are more design parameters in these two charts.

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Yildiz, Ozkan, Kelly Stano, Shaghayegh Faraji, Corinne Stone, Colin Willis, Xiangwu Zhang, Jesse S. Jur, and Philip D. Bradford. "High performance carbon nanotube – polymer nanofiber hybrid fabrics." Nanoscale 7, no. 40 (2015): 16744–54. http://dx.doi.org/10.1039/c5nr02732b.

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A novel hybridization process combining carbon nanotube sheet drawing and electrospinning is a versatile way to produce multifunctional, binder free fabrics which contain ultra high aspect ratio carbon nanotubes intermingled with polymer nanofibers.

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Journal articles on the topic 'Process performance ratio'

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