Study on BCN and BAN Ruled Surfaces in $\mathbb{E}^{3}$

Hamdy N. Abd-Ellah,Abdelrahim Khalifa Omran 강원경기수학회 2017 한국수학논문집 Vol.25 No.4

As a continuation to the study in [8, 12, 15, 17], we construct bi-conservative central normal (BCN) and bi-conservative asymptomatic normal (BAN) ruled surfaces in Euclidean 3-space $\mathbb{E}^{3}$. For such surfaces, local study is given and some examples are constructed using computer aided geometric design (CAGD).

Strengthening of Cutouts in Existing One-Way Spanning R. C. Flat Slabs Using CFRP Sheets

Hamdy K. Shehab,Ahmed S. Eisa,Kareem A. El-Awady 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.2

Openings in slabs are usually required for many different applications such as aeriation ducts and air conditioning. Opening in concrete slabs due to cutouts significantly decrease the member stiffness. There are different techniques to strengthen slabs with opening cutouts. This study presents experimental and numerical investigations on the use of Carbon Fiber Reinforced Polymers (CFRP) as strengthening material to strengthen and restore the load carrying capacity of R.C. slabs after having cutout in the hogging moment region. The experimental program consisted of testing five (oneway spanning R.C. flat slabs) with overhang. All slabs were prismatic, rectangular in cross-section and nominally 2000 mm long, 1000 mm width, and 100 mm thickness with a clear span (distance between supports) of 1200 mm and the overhang length is 700 mm. All slabs were loaded up to 30 kN (45% of ultimate load for reference slab, before yielding of the longitudinal reinforcement), then the load was kept constant during cutting concrete and steel bars (producing cut out). After that operation, slabs were loaded till failure. An analytical study using finite element analysis (FEA) is performed using the commercial software ANSYS. The FEA has been validated and calibrated using the experimental results. The FE model was found to be in a good agreement with the experimental results. The investigated key parameters were slab aspect ratio for the opening ratios of [1:1, 2:1], CFRP layers and the laminates widths, positions for cutouts and the CFRP configurations around cutouts.

Euler-Maruyama Numerical solution of some stochastic functional differential equations

( Hamdy M. Ahmed ) 한국산업응용수학회(구 한국산업정보응용수학회) 2007 한국산업정보응용수학회 Vol.11 No.1

Preparation and characterization of controlled-release doxazosin mesylate pellets using a simple drug layering-aquacoating technique

Hamdy Abdelkader,Heba A. Hazzah,Magda A. EL-Massik,Ossama Y. Abdallah 한국약제학회 2013 Journal of Pharmaceutical Investigation Vol.43 No.4

Pellets are one of multiparticulate pharmaceutical forms and can offer numerous technical and biopharmaceutical advantages compared with single dose unit formulations, e.g. tablets and capsules. This study aimed at formulation of controlled-release pellets of doxazosin mesylate (DM), a widely used treatment for antihypertensive and benign prostatic hyperplasia. DM was loaded onto microcrystalline cellulose CELLETS pellets using hydroalcoholic solution and alcoholic suspension layering techniques to achieve a minimum drug load of 4 mg DM/g pellets. DM-layered CELLETS were coated by Aquacoat dispersion (ready-made ethylcellulose dispersion) using a coating pan technique as a simple and widely utilized technique in pharmaceutical industry. Controlled-release DM-layered pellets showed a release profile comparable to the controlled-release commercial product Cardura XL Tablet. Also, the mechanism of DM release from Aquacoat CELLETS was mathematically modeled and imaged by scanning electron microscopy to elucidate drug release mechanisms from the prepared pellet formulations. Accelerated stability studies of the prepared pellets were performed under stress conditions of 40 C, and 75 % RH for 3 months. In conclusion, preparation of controlledrelease DM-layered CELLETS is feasible using a simple and conventional coating pan technology.

Effects of surfactant type and cholesterol level on niosomes physical properties and in vivo ocular performance using timolol maleate as a model drug

Hamdy Abdelkader,Usama Farghaly,Hossam Moharram 한국약제학회 2014 Journal of Pharmaceutical Investigation Vol.44 No.5

This study aimed at investigating the roles ofboth Span surfactant type (having a gel/liquid transitiontemperature range from\10 to 55 C), and cholesterol levelon in vitro characteristics and in vivo performance oftimolol maleate niosomes. Span 20, Span 40 and Span 60niosomes were prepared using the thin film hydrationmethod. Span:cholesterol levels employed were 7:3 mol/mol(a minimum concentration for stable niosomes) and1:1 mol/mol (a maximum concentration accommodated byniosomes). Niosomes were characterized for size, percentageentrapment efficiency, morphology, in vitro release andintra-ocular pressure (IOP) lowering activity in rabbits. Theorder of the area under IOP-time curve (AUC) was rankedas follows: Span 40[Span 20[Span 60. The AUC andIOPmax values for Span 40:cholesterol (7:3) niosomes weresuperior due to having a good compromise between thermoresponsivenessand efficient capacity for loading a significantdrug cargo, compared with Span 20 and Span 60.

Horizontal deformation in South Korea from permanent GPS network data, 2000-2003

Hamdy, A. M.,Park, P.-H.,Lim, H.-C. TERRA SCIENTIFIC PUBLISHING COMPANY 2005 Earth, planets, and space Vol.57 No.2

Simplified Design Procedure for Reinforced Concrete Columns Based on Equivalent Column Concept

Hamdy M. Afefy,El-Tony M. El-Tony 한국콘크리트학회 2016 International Journal of Concrete Structures and M Vol.10 No.3

Axially loaded reinforced concrete columns are hardly exist in practice due to the development of some bending moments. These moments could be produced by gravity loads or the lateral loads. First, the current paper presents a detailed analysis on the overall structural behavior of 15 eccentrically loaded columns as well as one concentrically loaded control one. Columns bent in either single curvature or double curvature modes are tested experimentally up to failure under the effect of different end eccentricities combinations. Three end eccentricities ratio were studied, namely, 0.1b, 0.3b and 0.5b, where b is the column width. Second, an expression correlated the decay in the normalized axial capacity of the column and the acting end eccentricities was developed based on the experimental results and then verified against the available formula. Third, based on the equivalent column concept, the equivalent pin-ended columns were obtained for columns bent in either single or double curvature modes. And then, the effect of end eccentricity ratio was correlated to the equivalent column length. Finally, a simplified design procedure was proposed for eccentrically loaded braced column by transferring it to an equivalent axially loaded pin-ended slender column. The results of the proposed design procedure showed comparable results against the results of the ACI 318-14 code.

The Role of Negative Binomial Sampling In Determining the Distribution of Minimum Chi-Square

Hamdy H.I.,Bentil Daniel E.,Son M.S. The Korea Contents Association 2007 International Journal of Contents Vol.3 No.1

The distributions of the minimum correlated F-variable arises in many applied statistical problems including simultaneous analysis of variance (SANOVA), equality of variance, selection and ranking populations, and reliability analysis. In this paper, negative binomial sampling technique is employed to derive the distributions of the minimum of chi-square variables and hence the distributions of the minimum correlated F-variables. The work presented in this paper is divided in two parts. The first part is devoted to develop some combinatorial identities arised from the negative binomial sampling. These identities are constructed and justified to serve important purpose, when we deal with these distributions or their characteristics. Other important results including cumulants and moments of these distributions are also given in somewhat simple forms. Second, the distributions of minimum, chisquare variable and hence the distribution of the minimum correlated F-variables are then derived within the negative binomial sampling framework. Although, multinomial theory applied to order statistics and standard transformation techniques can be used to derive these distributions, the negative binomial sampling approach provides more information regarding the nature of the relationship between the sampling vehicle and the probability distributions of these functions of chi-square variables. We also provide an algorithm to compute the percentage points of the distributions. The computation methods we adopted are exact and no interpolations are involved.

Anuria in a 9-Month-Old Infant Resulting from Ureteral Cystine Stones

Hamdy Aboutaleb 대한비뇨의학회 2011 Investigative and Clinical Urology Vol.52 No.9

Pediatric urolithiasis and calcular anuria in early infancy are rare. Cystine stones may develop in utero or during early infancy. We report the case of a female 9-month-old infant with obstructive anuria resulting from cystine stones in a single functioning unit. She presented to the emergency department owing to the absence of micturition for 3 days. Radiological investigations revealed four left ureteral stones and an atrophic right kidney resulting from a calcular obstruction. Her laboratory values were as follows: serum creatinine 6.7 mg/dl, Na 132 mEq/l, K 6 mg/dl, and hematocrit 32%. An urgent percutaneous nephrostomy tube was inserted into the left side for urinary drainage, and her serum levels of creatinine and K returned to normal within 3 days. A left ureterolithotomy was the final management. Stone analysis revealed pure cystine crystals.

Reconstruction of an Amputated Glans Penis With a Buccal Mucosal Graft: Case Report of a Novel Technique

Hamdy Aboutaleb 대한비뇨의학회 2014 Investigative and Clinical Urology Vol.55 No.12

Penile amputation is a rare catastrophe and a serious complication of circumcision. Reconstruction of the glans penis may be indicated following amputation. Our reportdiscusses a novel technique for reconfiguration of an amputated glans penis 1 year aftera complicated circumcision. A 2-year-old male infant presented to us with glans penisamputation that had occurred during circumcision 1 year previously. The parents complainedof severe meatal stenosis with disfigurement of the penis. Penis length was 3cm. Complete penile degloving was performed. The distal part of the remaining peniswas prepared by removing fibrous tissue. A buccal mucosal graft was applied to thedistal part of the penis associated with meatotomy. The use of a buccal mucosal graftis a successful and simple procedure with acceptable cosmetic and functional resultsfor late reconfiguration of the glans penis after amputation when penile size is suitable.