An Improved Mathematical Model of Resin Concrete and the Study of its Thermal Stability

An improved model with polygonal aggregates is proposed to analyze the thermal stability of the resin concrete in this paper. A 2D polygonal aggregates model is established to make the calculating results closer to the reality and the 2D model is the slice directly captured from the 3D model based on the predecessors theory. A comparison is made between the conventional model with spherical aggregates and the polygonal aggregates model in this paper. The results of the analysis on the improved model are closer to the previous research results and more accurate than the spherical aggregates model. It confirms that the polygonal aggregates model is accurate enough to analyze the properties of the resin concrete.

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Retailer’s Ordering and Discounting Policies Under Advance Sales Discount and Trade Credit Based on Sharia

Jurnal Teknologi ◽

10.11113/jt.v59.2575 ◽

2012 ◽

Vol 59 (2) ◽

Author(s):

Chairul Saleh ◽

Achmad Chairdino Leuveano ◽

Reny Lagaida ◽

Md. Razali Muhammad

Keyword(s):

Mathematical Model ◽

Cycle Time ◽

Trade Credit ◽

Price Discount ◽

Inventory Cost ◽

Conventional Model ◽

Credit Period ◽

Model Based ◽

Advance Sales ◽

Replenishment Cycle

The use of conventional model to minimize the inventory cost creates a disturbance between the sellers and buyers. It creates a usury since the payment conducts to interest paid and interest earned. In this paper, sharia principle is implemented, that is Bai Al Istishna which allows credit period and margin agreement as the payment. The model is engaged to replenishment cycle time and price discount policy to attract the customer’s demand which based on sharia principle. This paper provides a useful mathematical model based on sharia principles in order to usury/interest can be eliminated in the trading process.

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Effect of substrate concentration and temperature on the kinetics and thermal stability of cyclodextrin glycosyltransferase for the production of β-cyclodextrin: Experimental results vs. mathematical model

Process Biochemistry ◽

10.1016/j.procbio.2011.03.007 ◽

2011 ◽

Vol 46 (7) ◽

pp. 1399-1404 ◽

Cited By ~ 5

Author(s):

Sri Rezeki Muria ◽

Benjamas Cheirsilp ◽

Suleeporn Kitcha

Keyword(s):

Mathematical Model ◽

Thermal Stability ◽

Substrate Concentration ◽

Experimental Results ◽

Cyclodextrin Glycosyltransferase ◽

Thermal Stability Of

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A comparison of a two-dimensional depth averaged flow model and a three-dimensional RANS model for predicting tsunami inundation and fluid forces

10.5194/nhess-2018-150 ◽

2018 ◽

Cited By ~ 1

Author(s):

Xinsheng Qin ◽

Michael Motley ◽

Randall LeVeque ◽

Frank Gonzalez ◽

Kaspar Mueller

Keyword(s):

Built Environment ◽

3D Model ◽

Computational Cost ◽

Three Dimensional ◽

Vertical Direction ◽

3D Models ◽

Tsunami Inundation ◽

Model Based ◽

Fine Mesh ◽

2D Model

Abstract. The numerical modeling of tsunami inundation that incorporates the built environment of coastal communities is challenging for both depth-integrated 2D and 3D models, not only in modeling the flow, but also in predicting forces on coastal structures. For depth-integrated 2D models, inundation and flooding in this region can be very complex with variation in the vertical direction caused by wave breaking on shore and interactions with the built environment and the model may not be able to produce enough detail. For 3D models, a very fine mesh is required to properly capture the physics, dramatically increasing the computational cost and rendering impractical the modeling of some problems. In this paper, comparisons are made between GeoClaw, a depth-integrated 2D model based on the nonlinear shallow water equations (NSWE), and OpenFOAM, a 3D model based on Reynolds Averaged Navier-Stokes (RANS) equation for tsunami inundation modeling. The two models were first validated against existing experimental data of a bore impinging onto a single square column. Then they were used to simulate tsunami inundation of a physical model of Seaside, Oregon. The resulting flow parameters from the models are compared and discussed, and these results are used to extrapolate tsunami-induced force predictions. It was found that the 2D model did not accurately capture the important details of the flow near initial impact due to the transiency and large vertical variation of the flow. Tuning the drag coefficient of the 2D model worked well to predict tsunami forces on structures in simple cases but this approach was not always reliable in complicated cases. The 3D model was able to capture transient characteristic of the flow, but at a much higher computational cost; it was found this cost can be alleviated by subdividing the region into reasonably sized subdomains without loss of accuracy in critical regions.

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A mathematical model to control thermal stability of blast furnace using proactive thermal indicator

Ironmaking & Steelmaking ◽

10.1080/03019233.2017.1353765 ◽

2017 ◽

Vol 46 (2) ◽

pp. 133-140 ◽

Cited By ~ 5

Author(s):

Ashish Agrawal ◽

Mahesh K. Agarwal ◽

Anil K. Kothari ◽

Santanu Mallick

Keyword(s):

Mathematical Model ◽

Thermal Stability ◽

Blast Furnace ◽

Thermal Indicator ◽

Thermal Stability Of

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Analysis of the stress state in the harmonic drive generator-flexspline system in relation to selected structural parameters and manufacturing deviations

Bulletin of the Polish Academy of Sciences Technical Sciences ◽

10.2478/v10175-010-0073-8 ◽

2010 ◽

Vol 58 (4) ◽

pp. 683-698 ◽

Cited By ~ 7

Author(s):

W. Ostapski

Keyword(s):

Mathematical Model ◽

Stress State ◽

3D Model ◽

Structural Parameters ◽

Short Version ◽

Harmonic Drive ◽

Model Based

Analysis of the stress state in the harmonic drive generator-flexspline system in relation to selected structural parameters and manufacturing deviations In the paper, the problem of failure of the elastic bearing supporting the generator in a harmonic drive is presented. To analyse the cause of the failure, material investigations as well as simulations of the stress state in the bearing versus manufacturing deviations and fits between the bearing and the generator cam have been carried out. Studies on the stress state in the flexpline have also been conducted in dependence of such technological deviations and generator bearing-flexspline fits for the classical, short, and ultra-short version of the harmonic drive with different heights of the bottom. The simulations have been realised on a mathematical model based on analytical relationships and a 3D model with the aid of FEM.

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Study on Structures and Properties of CaSO4 Whiskers/PVC Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.234 ◽

2011 ◽

Vol 335-336 ◽

pp. 234-239 ◽

Cited By ~ 2

Author(s):

Shu Hua Zhang ◽

Wen Jun Gan ◽

Wu Xing Sun ◽

Chen Jun Ling ◽

Xie Wang ◽

...

Keyword(s):

Thermal Stability ◽

Optical Microscope ◽

Perfect Crystal ◽

Elongation At Break ◽

Research Results ◽

Structures And Properties ◽

Stability Time ◽

Perfect Crystal Structure ◽

Degradation Time ◽

Thermal Stability Of

Structures of CaSO4 whisker(A) and CaSO4 whisker(B) were characterized by IR and XRD, and the morphologies were observed by optical microscope. The results showed that the modified CaSO4 whisker(B) has perfect crystal structure, high crystallinity and less defects. Mechanical properties and static thermal stability time(190 °C) of two composites which were prepared by CaSO4 whisker(A) / PVC and CaSO4 whisker(B) / PVC were tested separately, and the degradation processes were analyzed by TG at 50 °C-400°C, N2 atmosphere, and the dispersing states of two whiskers in the composites were observed by means of optical microscope and SEM. The research results showed that the tensile strength and elongation at break increased over 3 MPa and 40% separately, and the static thermal stability time was over 90 min of CaSO4 whisker(B) / PVC, the initial degradation time was delayed comparing with CaCO3 / PVC composite. The consistency and interfacial configuration between whisker and PVC resin were perfect, and the toughness and thermal stability of the composite was improved after CaSO4 whisker was modified. The research results indicated that modified CaSO4 whisker has better toughness and thermal stability actions for PVC.

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The Ordered Phase Formation in Ti-Al-Ga Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069193 ◽

1970 ◽

Vol 28 ◽

pp. 440-441

Author(s):

Shiro Fujishiro ◽

Harold L. Gegel

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Titanium Alloys ◽

Growth Kinetics ◽

Stoichiometric Composition ◽

Good Potential ◽

Alpha Titanium ◽

Cold Rolled ◽

Kinetics Of ◽

Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

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Microstructure studies of tungsten silicide schottky contacts on Gaas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126445 ◽

1987 ◽

Vol 45 ◽

pp. 328-329

Author(s):

Yih-Cheng Shih ◽

E. L. Wilkie

Keyword(s):

Thermal Stability ◽

Field Effect Transistors ◽

Schottky Contact ◽

Schottky Contacts ◽

Excellent Thermal Stability ◽

Barrier Heights ◽

Gaas Substrates ◽

Film Adhesion ◽

Threshold Voltages ◽

Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

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