Optimal control of a large dam

A large dam model is an object of study of this paper. The parameters $L^{lower}$ and $L^{upper}$ are its lower and upper levels, $L=L^{upper}-L^{lower}$ is large, and if a current level of water is between these bounds, then the dam is assumed to be in normal state. Passage one or other bound leads to damage. Let $J_1$ $(J_2)$ denote the damage cost of crossing the lower (upper) level. It is assumed that input stream of water is described by a Poisson process, while the output stream is state-dependent (the exact formulation of the problem is given in the paper). Let $L_t$ denote the dam level at time $t$, and let $p_1=\lim_{t\to\infty}\mathbf{P}\{L_t= L^{lower}\}$, $p_2=\lim_{t\to\infty}\mathbf{P}\{L_t> L^{upper}\}$ exist. The long-run average cost $J=p_1J_1+p_2J_2$ is a performance measure. The aim of the paper is to choose the parameter of output stream (exactly specified in the paper) minimizing $J$.Comment: To appear in "Journal of Applied Probability" 44 (2007), No.

Design of Adiabatic MTJ-CMOS Hybrid Circuits

Low-power designs are a necessity with the increasing demand of portable devices which are battery operated. In many of such devices the operational speed is not as important as battery life. Logic-in-memory structures using nano-devices and adiabatic designs are two methods to reduce the static and dynamic power consumption respectively. Magnetic tunnel junction (MTJ) is an emerging technology which has many advantages when used in logic-in-memory structures in conjunction with CMOS. In this paper, we introduce a novel adiabatic hybrid MTJ/CMOS structure which is used to design AND/NAND, XOR/XNOR and 1-bit full adder circuits. We simulate the designs using HSPICE with 32nm CMOS technology and compared it with a non-adiabatic hybrid MTJ/CMOS circuits. The proposed adiabatic MTJ/CMOS full adder design has more than 7 times lower power consumtion compared to the previous MTJ/CMOS full adder

Development of wall-covering glass-ceramics from raw materials

The possibihty of producing wall-covering glass-ceramic materials from raw materials by crystallization of the glass is demonstrated. Glass-ceramics based on β-wollastonite and diopside with various ratios were designed from raw materials such as limestone and dolomite. The phases crystallized were examined by X-ray analysis. Thermal expansion and mechanical properties such as bending strength and microhardness for glasses and glass-ceramics were measured

Behavior of hybrid high-strength fiber reinforced concrete slab-column connections under the effect of high temperature

AbstractConcrete can be modified to perform in a more ductile form by the addition of randomly distributed discrete fibers in the concrete matrix. The combined effect of the addition of two types of fibers (steel fiber and polypropylene fiber with different percentages) to concrete matrix, which is called hybrid effect is currently under investigation worldwide. The current research work presents the conducted experimental program to observe the behavior of hybrid high strength reinforced concrete slab-column connections under the effect of high temperature. For this purpose, ten slab-column connections were casted and tested. The experimental program was designed to investigate the effect of different variables such as concrete mixture, column location and temperature fighting system. All specimens were exposed to a temperature of 500°C for duration of two hours. To observe the effect of each variable, specimens were divided into four groups according to the studied parameters. The test results revealed that using hybrid high strength concrete HFHSC produced more strength in punching failure compared with high strength concrete HSC when exposed to elevated temperature. Fighting by air had higher initial crack load compared with that for without fighting and fighting by water. On the other hand, fighting by water decreased the ultimate load

Crystallization of osumilite from modified basaltic glasses

Osumilite-type phases, which have high temperature stability and low linear thermal expansion coefficients, were crystallized from modified basalt glass composition. To satisfy the compositional requirements of osumilite molecules, a deliberate amount of kaolin, sand, magnesite and TiO2 should be added to the basalt. The crystallization process was investigated by DTA, X-ray diffractometry and SEM. The effect of compositional changes on bulk crystallization and growth morphology was also studied. The linear thermal expansion coefficient was measured to characterize the produced glass-ceramics

Extracorporeal Shockwave Therapy for Painful Chronic Traumatic Heterotopic Ossification after Right Acetabulum Fracture Fixation: A Case Report and Literature Review

BACKGROUND: Heterotopic ossification (HO) usually occurs in trauma, such as fractures. To the best of our knowledge, there is a lack of studies about the effects of shockwave on the size of HO in the literature. AIM: The aim of this study was to describe the effects of extracorporeal shockwave therapy (ESWT) on the size of HO as well as the lower extremity functions in patients with fracture right acetabulum. CASE REPORT: A 36-year-old gentleman had a traffic accident on August 30, 2015, resulted in a fracture of the right acetabulum treated by open reduction and internal fixation on September 2, 2015. The patient has complained of severe right hip pain with limitation of daily activities, especially walking, standing, and sitting, visual analog scale about 7-8/10 with painful and restricted ROM of the right hip. Plain X-ray of the right hip revealed HO at greater trochanter with a long axis length 37.3 mm. ESWT was applied for HO. ESWT was administered 6 times each weekly for 6 weeks. At 6-month follow-up, the size of HO had become slightly smaller with the improvement of pain, and lower extremities functions. DISCUSSION: Soft tissues around HO have been regenerated from ischemia for several reasons such as ESWT stimulating angiogenesis and neurogenesis and the size of HO had become slightly smaller by radial shockwave therapy. CONCLUSION: ESWT is a novel non-invasive and safe treatment for HO. The effects of ESWT on the size of HO had become slightly smaller with the improvement of lower extremities functions

Effect of Different Growth Conditions on Certain Biochemical Parameters of Different Cyanobacterial Strains

Aims: Variation in the traditional growth medium conditions to enhance the production of lipids, carbohydrates, protein and the free amino acids content of three cyanobacterial species. Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.). Conclusion, significance and impact of study: Aerated enriched glucose medium (1%, w/v) was the best growth medium condition used in the present study