The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the interface between adjacent control volumes. A temperature dependent specific heat capacity proposed by a 4th Degree polynomial is fitted. A good agreement is obtained when the predicted results are compared with those obtained from the analytical solution.
In this paper, new concepts which are called: left derivations and generalized left derivations in nearrings have been defined. Furthermore, the commutativity of the 3-prime near-ring which involves some
algebraic identities on generalized left derivation has been studied.
(1)
This research introduce a study with application on Principal Component Regression obtained from some of the explainatory variables to limitate Multicollinearity problem among these variables and gain staibilty in their estimations more than those which yield from Ordinary Least Squares. But the cost that we pay in the other hand losing a little power of the estimation of the predictive regression function in explaining the essential variations. A suggested numerical formula has been proposed and applied by the researchers as optimal solution, and vererifing the its efficiency by a program written by the researchers themselves for this porpuse through some creterions: Cumulative Percentage Variance, Coefficient of Determination, Variance
... Show MoreThe significance of interpretation for linguists varied , and its methods varied between appreciations, deletion, understanding the meaning
ان العقد – في تكوينه – عبارة عن اتفاق ارادتين من اجل احداث اثر قانوني معين ، بيد ان العقد نفسه – في آثاره – يخضع لمجموع الالتزامات التي تشكلت طبقاً لما انصرفت اليه ارادة طرفيه ، فضلاً عمّا تيسّر من احكام اخرى فرضها المشرع او العرف او العدالة او مبادئ حسن النية .
This study was carried out to investigate the preparation of thermosetting polymeric blend consisting of three adhesive types, namely: epoxy, polyvinyl formal (PVF) and unsaturated polyester. Both of epoxy and PVF were used as a matrix-binder at fixed weight. Whilst unsaturated polyester was used at different weights and added to the matrix so as to produce prepared epoxy-PVF-unsaturated polyester blend. Several experiments were performed at different operating conditions, mixing speed and time at room temperature to identify the most favorable operating conditions. The optimum mixing speed and mixing time for the prepared blend were 500rpm and 5 minutes respectively.
Solid wastes-synthetic sack fib
... Show Moreמבוא
אין איזה סוג מן הספק ש החוקרים התמזג ו בתאריכי החברות הישנות מצדדים שונים ,
פוליטיים, חברתיים או מחשבתיים. שהספרות נחשב ת אחת תעודותיה של הידיעה
החשובות ביותר שתאפשר להישען עליה ולשאוב את הידיעות ליצירות הגנוז ות בחברה
מהחברות שיהיה קשה לפעמים רבים לדעת אות ן מתוך מקורותיה של הידיעה לפי
הכתיבות הפוליטיות,החברתיות,פולסופיות וכ.... (1)
הסופר הוא צורתה של החברה , הנושאים שלו הם הבעות והרגשות עצמיות ו
This paper is an applied study of the temporal meaning of structure, to assess the strength of time-dependent expressions as a framework for the action or verb
Prophecy in general, and Muhammadism in particular, can not seem to go away from life, or lag behind it, because it was originally for reform. It can not succeed in achieving this reform. It has grown away from it, and its conditions have not caused it to vary and diversify. These conditions, from its origin to its tranquility, its stillness and its movements, are based on a wise divine workmanship and a strict divine planning that suits the performance of this personality
In this paper the experimentally obtained conditions for the fusion splicing with photonic crystal fibers (PCF) having large mode areas were reported. The physical mechanism of the splice loss and the microhole collapse property of photonic crystal fiber (PCF) were studied. By controlling the arc-power and the arc-time of a conventional electric arc fusion splicer (FSM-60S), the minimum loss of splicing for fusion two conventional single mode fibers (SMF-28) was (0.00dB), which has similar mode field diameter. For splicing PCF (LMA-10) with a conventional single mode fiber (SMF-28), the loss was increased due to the mode field mismatch.
This work aims to investigate the tensile and compression strengths of heat- cured acrylic resin denture base material by adding styrene-butadiene (S- B) to polymethyl methacrylate (PMMA). The most well- known issue in prosthodontic practice is fracture of a denture base. All samples were a blend of (90%, 80%) PMMA and (10%, 20%) S- B powder melted in Oxolane (Tetra hydro furan). These samples were chopped down into specimens of dimensions 100x10x2.5mm to carry out the requirements of tensile tests. The compression strength test specimens were shaped into a cylinder with dimensions of 12.7mm in diameter and 20mm in length. The experimental results show a significant increase in both tensile and compression strengths when compared to cont
... Show More
(8)
(2)
