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Three-way catalytic converter (TWC) is considered as the most effective solution to reduce emissions in new electric fuel injection engines. The usage of the TWC on carburetor system will not promo...

Designing and manufacturing a combined system that utilizes the thermal energy of coolant and exhaust gases from Internal Combustion Engines (ICE) to distill fresh water from seawater on Vietnamese offshore fishing vessels is an education ministry-level project that the research team is working on. Utilizing this heat sources not only improve heat efficiency, but also provide fresh water on equipped vehicles. The experimental process shows that, the heat energy emission changes consecutively according to the ICE modes, directly affects the performance of the heat recovery equipment as well as the performance of the system. The content of this paper will present the process of designing a waste heat recovery tube by assessing the effect of heat exchanger structure in exhaust heat recovery equipment to the heat transfer efficiency between exhaust gases and sea water. The studies were conducted on Ansys Fluent software, in which the input data was determined from experimental data. The research results depict that the exhaust heat recovery efficiency is highly dependent on the heat exchanger fins structure. With a reasonable format, the heat recovery efficiency can reach up to 40% in most engine operating modes which lead to an improvement of approximately 12% of the total input energy.

The noble metals (Pt, Pd, Rh) supported on Cu-Ce mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate were investigated as catalytic performance of Three Way Catalysts (TWC) under simulated automotive exhaust feed gas. The structural, morphological features and catalytic activity were observed by X-ray diffractometry (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS) and GC-TCD (Varian CP-4900). The catalytic performance of noble metals (Pt, Rh, Pd) supported on Cu-Ce mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate was be compared with noble metals (Pt, Rh, Pd) supported on Ce-Zr mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate and only γ-Al2O3 washcoat/FeCrAl substrate at various stoichiometric ratio of oxygen. The results showed that the addition of Cu-Ce mixed oxides improved CO oxidation reaction at lower temperature during stable lambda of 1, the highest CO conversion of 99% is observed for the noble metals (Pt, Pd, Rh) support on Cu-Ce with γ-Al2O3 washcoat/FeCrAl substrate. The results also showed that, the addition of Cu-Ce mixed oxides promoted released oxygen, thus it improved strongly CO and C3H8 conversion at lean oxygen stoichiometric operation.

The aim of this paper is to extend the results in [E. Bolthausen, Exact convergence rates in some martingale central limit theorems, Ann. Probab., 10(3):672–688, 1982] and [J.C. Mourrat, On the rate of convergence in the martingale central limit theorem, Bernoulli, 19(2):633–645, 2013] to the L1-distance between distributions of normalized partial sums for martingale-difference sequences and the standard normal distribution.

For a double array of random elements fXmn;m 1;n 1g in a p-uniformly smooth Banach space, fbmn;m 1;n 1g is an array of positive numbers, convergence of double random series ∑ 1=1 ∑ 1=1Xmn, ∑ 1 m=1 ∑ 1 n=1 b 1 mnXmn and strong law of large numbers b 1 mn m ∑ i=1 n ∑ j=1 Xij ! 0 as m ^ n ! 1

For a double array of random elements {Vmn;m ‚ 1,n ‚ 1} in a real separable Banach space, some mean convergence theorems and weak laws of large numbers are established. For the mean conver- gence results, conditions are provided under which k i 1 r mn P um i=1 P vn j=1 (Viji E(Vij|Fij)) ! 0 in Lr (0 < r < 2). The weak law results provide con- ditions for k i 1 r mn P Tm i=1 P ?n j=1 (Vij i E(Vij|Fij)) ! 0 in probability where {Tm;m ‚ 1} and {?n;n ‚ 1} are sequences of positive integer-valued random variables, {kmn;m ‚ 1,n ‚ 1} is an array of positive integers. The sharpness of the results is illustrated by examples.

In this paper we establish Marcinkiewicz-Zygmund type laws of large numbers for double arrays of random elements in Banach spaces. Our results extend those of Hong and Volodin [6].

It is shown that in an infinite-dimensional dually separated second category topological vector space X there does not exist a probability measure μ for which the kernel coincides with X. Moreover, we show that in “good” cases the kernel has the full measure if and only if it is finitedimensional. Also, the problem posed by S. Chevet [Kernel associated with a cylindrical measure, Springer-Verlag, 1981, p. 69] is solved by proving that the annihilator of the kernel of a measure μ coincides with the annihilator of μ if and only if the topology of μ-convergence in the dual space is essentially dually separated.