Application of Monte-Carlo statistical experiments in design of ocean engineering - Estimating the parameters, models and probabilities

Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long- term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms.

The Statistical Experimental Design for Chemical Reactors Modeling

The Statistical Experimental Design techniques are the most powerful tools for the chemical reactors experimental modeling. Empirical models can be formulated for representing the chemical behavior of reactors with the minimal effort in the necessary number of experimental runs, hence, minimizing the consumption of chemicals and the consumption of time due to the reduction in the number of experimental runs and increasing the certainty of the results. Four types of nonthermal plasma reactors were assayed seeking for the highest efficiency in obtaining hydrogen and ethylene. Three different geometries for AC high voltage driven reactors, and only a single geometry for a DC high voltage pulse driven reactor were studied. According to the fundamental principles of chemical kinetics and considering an analogy among the reaction rate and the applied power to the plasma reactor, the four reactors are modeled following the classical chemical reactors design to understand if the behavior of the nonthermal plasma reactors can be regarded as the chemical reactors following the flow patterns of PFR (Plug Flow Reactor) or CSTR (Continuous Stirred Tank Reactor). Dehydrogenation is a common elimination reaction that takes place in nonthermal plasmas. Owing to this characteristic, a paraffinic heavy oil with an average molecular weight corresponding to C15 was used to study the production of light olefins and hydrogen.

An Efficient Three-Party Authenticated Key Exchange Procedure Using Chebyshev Chaotic Maps with Client Anonymity

Internet of Things(IoT)applications can be found in various industry areas,including critical infrastructure and healthcare,and IoT is one of several technological developments.As a result,tens of billions or possibly hundreds of billions of devices will be linked together.These smart devices will be able to gather data,process it,and even come to decisions on their own.Security is the most essential thing in these situations.In IoT infrastructure,authenticated key exchange systems are crucial for preserving client and data privacy and guaranteeing the security of data-in-transit(e.g.,via client identification and provision of secure communication).It is still challenging to create secure,authenticated key exchange techniques.The majority of the early authenticated key agreement procedure depended on computationally expensive and resource-intensive pairing,hashing,or modular exponentiation processes.The focus of this paper is to propose an efficient three-party authenticated key exchange procedure(AKEP)using Chebyshev chaotic maps with client anonymity that solves all the problems mentioned above.The proposed three-party AKEP is protected from several attacks.The proposed three-party AKEP can be used in practice for mobile communications and pervasive computing applications,according to statistical experiments and low processing costs.To protect client identification when transferring data over an insecure public network,our three-party AKEP may also offer client anonymity.Finally,the presented procedure offers better security features than the procedures currently available in the literature.

Combining the People Power and the Process Power to Achieve Six Sigma Process Capability——A Case Study

Achieving Six-Sigma process capability starts with l istening to the Voice of the Customers, and it becomes a reality by combining th e People Power and the Process Power of the organisation. This paper presents a Six-Sigma implementation case study carried out in a magnet manufacturing compa ny, which produces bearing magnets to be used in energy meters. If the thickness of the produced bearing magnets is between 2.35 mm and 2.50 mm, they will be ac cepted by the customers. All the time the company could not produce the bearing magnets within the specified thickness range, as their process distribution was flat with 2.20 mm as lower control limit and 2.60 mm as upper control limit. This resulted in a huge loss in the form of non-conformities, loss of time and goodwill. The process capability of the company then was around 0.40. Organisat ion restructuring was carried out to reap the benefit of the People Power of the organisation. Statistically designed experiments (Taguchi Method based Design o f Experiments), Online quality control tools (Statistical Process Control To ols) were effectively used to complete the DMAIC (Define, Measure, Analyse, Impr ove and Control) cycle to reap the benefit of the Process Power of the organisat ion. Presently the company enjoys a process capability of 1.75, a way towards Si x-Sigma Process Capability.

Effect of Operating Parameters on Carbon Dioxide Depressurized Regeneration in Circulating Fluidized Bed Downer using Computational Fluid Dynamics

Typically,heating or high-temperature treatment has been used to regenerate solid sorbent.In this study,the depressurized regeneration using a circulating fluidized bed downer was proposed and the significance of its operating parameters was identified.Two-dimensional computational fluid dynamics were employed to systematically investigate the effects of operating parameters on carbon dioxide depressurized regeneration with potassium carbonate solid sorbent particles.The simulated model was based on a laboratory scale circulating fluidized bed downer.The chemical equilibrium model for predicting the highest outlet carbon dioxide mass fraction was then used.A central composite design was employed to identify the main,quadratic,and interaction effects of operating parameters to the regeneration process.The operating parameters consisted of the outlet system pressure,inlet gas velocity,and inlet solid circulation rate,while the response variable was the released outlet carbon dioxide mass fraction.Among the multiple operating parameters,there were two main operating parameters and their combinations,namely the inlet gas velocity,outlet system pressure,square of inlet gas velocity,and interaction between inlet gas velocity and outlet system pressure,which had great impacts on the regeneration.All the main,quadratic,and interaction effects were explained.Then,the optimal operating conditions were obtained through the response surface method.

Simultaneous saccharification and fermentation of wheat bran flour into ethanol using coculture of amylotic Aspergillus niger and thermotolerant Kluyveromyces marxianus

Studies on simultaneous saccharification and fermentation(SSF)of wheat bran flour,a grain milling residue as the substrate using coculture method were carried out with strains of starch digesting Aspergillus niger and nonstarch digesting and sugar fermenting Kluyveromyces marxianus in batch fermentation.Experi-ments based on central composite design(CCD)were conducted to maximize the glucose yield and to study the effects of substrate concentration,pH,temperature,and enzyme concentration on percentage conversion of wheat bran flour starch to glucose by treatment with fungalα-amylase and the above parameters were optimized using response surface methodology(RSM).The optimum values of substrate concentration,pH,temperature,and enzyme concentration were found to be 200g/L,5.5,65℃ and 7.5IU,respectively,in the starch saccharification step.The effects of pH,temperature and substrate concentration on ethanol concentration,biomass and reducing sugar concentration were also investigated.The optimum temperature and pH were found to be 30℃ and 5.5,respectively.The wheat bran flour solution equivalent to 6%(w/V)initial starch concentration gave the highest ethanol concentrationof 23.1g/Lafter 48hoffermentation at optimum conditions of pH and temperature.The growth kinetics was modeled using Monod model and Logistic model and product formation kinetics using Leudeking-Piret model.Simultaneous saccharificiation and fermenta-tion of liquefied wheat bran starch to bioethanol was studied using coculture of amylolytic fungus A.niger and nonamylolytic sugar fermenting K.marxianus.

Effect of a pulsating flow on hydrodynamics and fluid catalytic cracking chemical reaction in a circulating fluidized bed riser

The three-dimensional computational fuid dynamics(3D-CFD)of a pulsating flow applied to the fluid catalytic cracking(FCC)reaction was investigated in the riser of a circulating fluidized bed reactor.The kinetic parameters of the FCC and coke burning reactions for predicting the reactant conversion and product yield percentages were applied.To increase the reactant conversion level and product yield.the effect of the pulsating flow operating parameters was considered using a 2k statistical experimental design with four factors(amplitude,frequency,types of the waveform,and amplitude ratio).The 3DCFD simulation was successfully validated from the experimental literature data.The frequency and type of the waveform were found to be the significant operating parameters.The expression of the fitted regression model and response surface contour were derived and revealed that the pulsating flow provides a higher reactant conversion level and product yield percentages compared to a non-pulsating or steady flow.