Li Li¹, Chen Cui^1,2, Jianfeng Lu¹, Shanqing Zhang^1,*, Ching-Chun Chang³

Computer Systems Science and Engineering, Vol.38, No.3, pp. 291-303, 2021, DOI:10.32604/csse.2021.016340

Abstract As an efficient technique for anti-counterfeiting, holographic diffraction labels has been widely applied to various fields. Due to their unique feature, traditional image recognition algorithms are not ideal for the holographic diffraction label recognition. Since a tensor preserves the spatiotemporal features of an original sample in the process of feature extraction, in this paper we propose a new holographic diffraction label recognition algorithm that combines two tensor features. The HSV (Hue Saturation Value) tensor and the HOG (Histogram of Oriented Gradient) tensor are used to represent the color information and gradient information of holographic diffraction label, respectively. Meanwhile, the tensor… More >

Harsh Tripathi¹, Amer Ibrahim Al-Omari², Mahendra Saha¹, Ayed R. A. Alanzi^3,*

Computer Systems Science and Engineering, Vol.38, No.3, pp. 381-392, 2021, DOI:10.32604/csse.2021.015624

Abstract Recently, the Darna distribution has been introduced as a new lifetime distribution. The two-parameter Darna distribution represents is a mixture of two well-known gamma and exponential distributions. A manufacturer or an engineer of products conducts life testing to examine whether the quality level of products meets the customer’s requirements, such as reliability or the minimum lifetime. In this article, an attribute modified chain sampling inspection plan based on the time truncated life test is proposed for items whose lifetime follows the Darna distribution. The plan parameters, including the sample size, the acceptance number, and the past lot result of the… More >

Md Sadikur Rahman¹, Emad E. Mahmoud², Ali Akbar Shaikh^1,*, Abdel-Haleem Abdel-Aty^3,4, Asoke Kumar Bhunia¹

Computer Systems Science and Engineering, Vol.38, No.3, pp. 351-364, 2021, DOI:10.32604/csse.2021.015451

Abstract The present paper aims to develop the Kuhn-Tucker and Fritz John criteria for saddle point optimality of interval-valued nonlinear programming problem. To achieve the study objective, we have proposed the definition of minimizer and maximizer of an interval-valued non-linear programming problem. Also, we have introduced the interval-valued Fritz-John and Kuhn Tucker saddle point problems. After that, we have established both the necessary and sufficient optimality conditions of an interval-valued non-linear minimization problem. Next, we have shown that both the saddle point conditions (Fritz-John and Kuhn-Tucker) are sufficient without any convexity requirements. Then with the convexity requirements, we have established that… More >

Mostafa Zaydan¹, Mehdi Riahi^1,2,*, Fateh Mebarek-Oudina³, Rachid Sehaqui¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 789-819, 2021, DOI:10.32604/fdmp.2021.015422

Abstract Steady, laminar mixed convection inside a lid-driven square cavity filled with nanofluid is investigated numerically. We consider the case where the right and left walls are moving downwards and upwards respectively and maintained at different temperatures while the other two horizontal ones are kept adiabatic and impermeable. The set of nonlinear coupled governing mass, momentum, and energy equations are solved using an extensively validated and a highly accurate finite difference method of fourth-order. Comparisons with previously conducted investigations on special configurations are performed and show an excellent agreement. Meanwhile, attention is focused on the heat transfer enhancement when different nano-particles:… More >

Qingzhuo Chi¹, Huimin Chen¹, Lizhong Mu^1,*, Ying He¹, Yong Luan²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 721-743, 2021, DOI:10.32604/fdmp.2021.015200

Abstract Type A aortic dissection (AD) is one of the most serious cardiovascular diseases, whose risk predictors are controversial. The purpose of this research was to investigate how elongation accompanied by dilation of the ascending aorta (AAo) affects the relevant haemodynamic characteristics using image-based computational models. Five elongated AAos with different levels of dilation have been reconstructed based on the centerlines data of an elderly and an AD patient. Numerical simulations have been performed assuming an inflow waveform and a Windkessel model with three elements for all outflow boundaries. The numerical results have revealed that the elongation of AAo can disturb… More >

Yukun Lv, Quanzhi Ge^*, Zhuang Wei, Shuang Yang

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 833-844, 2021, DOI:10.32604/fdmp.2021.015082

Abstract The splitter is an important component of water-based cooling systems used to extract heat from computer boards. In the present study, the flow characteristics of a 16-splitter structure were numerically simulated and compared with experimental results to verify the reliability of the numerical simulation method. Accordingly, the concept of splitter structural coefficients was proposed. Based on the results of this study, we recommend a selection range of 5 ≤ k ≤ 6 for the structure factor k of the splitter; after optimization, the maximum deviation of the splitter outlet flow was reduced from the original value of 100% to 8.3%. More >

Quanbin Ba^1,2, Yanbao Liu^1,2,*, Zhigang Zhang^1,2, Wei Xiong^1,2, Kai Shen^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 697-710, 2021, DOI:10.32604/fdmp.2021.014762

Abstract The characteristics of the flow field associated with a multi-hole combined external rotary bit have been studied by means of numerical simulation in the framework of an RNG k-ε turbulence model, and compared with the results of dedicated rock breaking drilling experiments. The numerical results show that the nozzle velocity and dynamic pressure of the nozzle decrease with an increase in the jet distance, and the axial velocity of the nozzle decays regularly with an increase in the dimensionless jet distance. Moreover, the axial velocity related to the nozzle with inclination angle 20° and 30° can produce a higher hole… More >

Xulan Wang^1,*, Zezhong Chen¹, Changzhen Liu¹, Wei Ren², Bo Wu¹, Shude Ji¹, Xiaofei Chen¹, Shijie Wen¹, Yonggang Hao¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 821-831, 2021, DOI:10.32604/fdmp.2021.014707

Abstract Taking the combustor composite structure of a high-strength diesel engine as the main research object, dedicated tests have been conducted to verify the accuracy of three distinct cylinder gasket pressure simulation models. Using the measured cylinder gasket compression rebound curve, a gasket unit has been designed and manufactured. For this unit, the influence of the bolt pretension, cylinder body and cylinder head material on gasket sealing pressure has been investigated systematically in conditions of thermo-mechanical coupling. The results show that the bolt pretension force is one of the most important factors affecting the cylinder gasket sealing pressure. The change of… More >

Huali Guo^*, Zhilong Zhang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 745-757, 2021, DOI:10.32604/fdmp.2021.014651

Abstract In some competitions the rules clearly state that all participating cars must install a restrictor valve structure in the intake system of the engine. The intake air volume of the engine is considerably affected due to the existence of such a valve. Indeed, a small interface diameter through which gas flows can lead to considerable flow resistance and loss. In this study, a four-cylinder engine for FSC racing is analyzed using a combined method based on numerical simulation and experiments. The analysis reveals that the main factors affecting the intake air volume are the intake manifold and the volume of… More >

Yulin Jiang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 759-772, 2021, DOI:10.32604/fdmp.2021.014470

Abstract When a pipe is partially filled with a given working liquid, the relationship between the electromotive force (EMF) measured by the sensor (flowmeter) and the average velocity is nonlinear and non-monotonic. This relationship varies with the inclination of the pipe, the fluid density, the pipe wall friction coefficient, and other factors. Therefore, existing measurement methods cannot meet the accuracy requirements of many industrial applications. In this study, a new processing method is proposed by which the flow rate can be measured with an ordinary electromagnetic flowmeter even if the pipe is only partially filled. First, a B-spline curve fitting method… More >