http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Mohamed A. Aboamer,Doaa H. Elgohary,Ali Abdullah Almukil,Ahmed A. Aboamer,Ibrahim M Alarifi,Mohsen Bakouri,Nader A. Rahman Mohamed 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.7
This study aims to examine the mechanical properties of acrylonitrile butadiene styrene specimens using ASTM 638, 695, and 790. UVC radiation was also used as a sterilizing method. The fused deposition modeling of 3D-printed polymerize with 30 % filling was used to manufacture 30 specimens for tensile, compression, and bending. Half of the specimens were treated with UVC, whereas the other half were not. The chosen dosage of 13.5 J/cm 2 with an exposure time of 48 min corresponds to 3650 sterilization treatments or 10 years of sterilization. The average ultimate stress in the tensile test, compression test, and bending test was 34.5 ± 7.4, 25.4 ± 0.5, and 24.5 ± 2.1 Mpa, respectively. The analysis of variance test shows that UVC radiation has a demonstrable influence on tensile specimens, with a P-value of 0.012, which is less than the significance threshold of 0.05. Thus, the null hypothesis is rejected.
Mohamed A. Aboamer,Ahmed A. Aboamer,Doaa H. Elgohary,Tarek M. Alqahtani,Ahmed Abdel-Hadi,Samiya M. Al-Mutairi,Tarek M. El-Bagory,Khaled M. Alshareef,Nader A. Rahman Mohamed 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12
The aim of this research is to investigate the sterilizing effect of UVB radiation on the degradation and oxidation of low- and high-density polyethylene specimens using ASTM 638 and 695. Polyethylene is a reliable, efficient, and low-cost biomaterial and an alternative to various bone transplants. Twenty high-density polyethylene (HDPE) specimens and twenty low-density polyethylene (LDPE) specimens were used for tensile and compression testing. The dosage of 13.5 J/cm 2 was chosen with an exposure time of 48 minutes during the sterilization process. In terms of mechanical tensile properties, LDPE has a lower effect compared with HDPE. The p-value of yield stress equals 3.008×10 -4 , the p-value of ultimate stress equals 2.5×10 -4 , and the p-value of break stress equals 0.0075.
Effect of DUPIC Cycle on CANDU Reactor Safety Parameter
Nader M.A Mohamed,Alya Badawi 한국원자력학회 2016 Nuclear Engineering and Technology Vol.48 No.5
Although, the direct use of spent pressurized water reactor (PWR) fuel in CANda Deuterium Uranium (CANDU) reactors (DUPIC) cycle is still under investigation, DUPIC cycle is a promising method for uranium utilization improvement, for reduction of high level nuclear waste, and for high degree of proliferation resistance. This paper focuses on the effect of DUPIC cycle on CANDU reactor safety parameters. MCNP6 was used for lattice cell simulation of a typical 3,411 MWth PWR fueled by UO2 enriched to 4.5w/o U-235 to calculate the spent fuel inventories after a burnup of 51.7 MWd/kgU. The code was also used to simulate the lattice cell of CANDU-6 reactor fueled with spent fuel after its fabrication into the standard 37-element fuel bundle. It is assumed a 5-year cooling time between the spent fuel discharges from the PWR to the loading into the CANDU-6. The simulation was carried out to calculate the burnup and the effect of DUPIC fuel on: (1) the power distribution amongst the fuel elements of the bundle; (2) the coolant void reactivity; and (3) the reactor point-kinetics parameters.
Nader A. Al Theeb,Mohammed S. Obeidat,Manar Aljarrah,Theyab A. Alhwiti 대한산업공학회 2019 Industrial Engineeering & Management Systems Vol.18 No.4
A single machine scheduling problem with sequence-dependent setup times and setup costs has a critical role in manufacturing and service sectors to minimize orders delays and costs. This study provides multiple objectives model tosolve the single machine total weighted tardiness and setup costs scheduling problem associated with sequencedependent setup times and sequence-dependent setup costs (MOSTWTSCSD). The objectives are to minimize thetotal weighted tardiness and the total setup costs for all jobs without any certain relationship between the setup timeand the setup cost, as happened in some machines. An alternative heuristic procedure based on discrete particle swarmoptimization (DPSO) is suggested to find representative Pareto front (non-dominated) solutions. Many efficient methods have been used inside the DPSO to improve its performance. Results show that the ability of the suggested solution approach to provide a representative Pareto fronts in reasonable computational efforts compared with anotherheuristic.
Nader Dehghani,Mohamad Reza Fouladivanda,Mohamed Amin Ghobadifar,Gelayol Safshekan-Esfahani,Armin Akbarzadeh 전남대학교 의과학연구소 2015 전남의대학술지 Vol.51 No.1
The current study aimed to determine the efficacy of probing with adjunctive mitomycinC (MMC) as a treatment for nasolacrimal duct obstruction (NLDO) in adults and tostudy the association of probing success with demographic and obstructioncharacteristics. This was a prospective, randomized, double-blind, placebo-controlledtrial including 140 patients (each with a unilateral NLDO) scheduled for nasolacrimalprobing who were randomly assigned to receive MMC (0.2 mg/ml, 70 patients; groupA) or placebo (normal saline, 70 patients; group B). Irrigation was carried out with 0.5cc of MMC (0.2 mg/mL) in the duct with a nasal pack for 10 minutes in group A. Patients’postprobing epiphora was evaluated at 2 weeks and 1, 3, 6, and 9 monthspostoperatively. Probing was judged to be a success if there was no or mild wateringfor at least 9 months after the procedure. There were no significant differences betweenthe two study groups in demographic characteristics or duration of the operation(p=0.062). The overall success rate of probing with MMC was 47/70 (67.1%), which wassignificantly higher than the success rate of the procedure with placebo (p=0.0027). When the sex of the patients was controlled for by logistic regression, a significant associationbetween the failure rate of probing and increasing age was found in cases andcontrols (p=0.004 vs. p=0.006, respectively). No significant side effects of probing withMMC were noted after 9 months of follow-up. Administering MMC in a dosage of 0.2mg/mL during nasolacrimal probing significantly increased the success rate of probing. The failure rate of probing increased with age. A low dose of MMC is cheap, safe, andeasily accessible; thus, it is recommended during nasolacrimal probing, especially inpatients who refuse dacryocystorhinostomy surgery.
Nader Al Theeb,Mohammed Hayajneh,Naqaa AL Qubelat 대한산업공학회 2020 Industrial Engineeering & Management Systems Vol.19 No.4
A new optimization model and solution approach for the Electric Vehicle Routing Problem (EVRP) is presented in this research, where the electric vehicles are used to deliver the products from manufacturing plant to multiple customers through a split delivery system which allows vehicles to partially recharged and return to a depot to get more loads if needed. The proposed model is a Mixed Integer Linear Programming (MILP) model used to determine the optimal route achieving the desired objective function for each vehicle which ensures maximization of customer satisfaction by minimizing total amount deviations and minimization of total distribution time. CPLEX solver is used to solving the different sizes of data sets to test the performance of the model, while a new heuristic approach is constructed to solve the same data sets. Then the results of the heuristic are compared with those obtained by CPLEX. The results of the small size data sets show that the CPLEX and heuristic obtain a competitive solution in terms of both computation time and solution quality. For medium-size data sets, the proposed heuristic can find the same or better solution for some of them compared with the result produced by CPLEX.
A Performance Comparison between XEN and KVM Hypervisors While Using Cryptographic Algorithms
Mohammed Al-Shalabi,Waleed K. Abdulraheem,Jafar Ababneh,Nader Abdel Karim International Journal of Computer ScienceNetwork S 2024 International journal of computer science and netw Vol.24 No.1
Cloud Computing is internet-based computing, where the users are provided with whatever service they need from the resources, software, and information. Recently, the security of cloud computing is considered as one of the major issues for both cloud service providers CSP and end-users. Privacy and highly confidential data make many users refuse to store their data within cloud computing, since data on cloud computing is not dully secured. The cryptographic algorithm is a technique which is used to maintain the security and privacy of the data on the cloud. In this research, we applied eight different cryptographic algorithms on Xen and KVM as hypervisors on cloud computing, to be able to measure and compare the performance of the two hypervisors. Response time and CPU utilization while encryption and decryption have been our aspects to measure the performance. In terms of response time and CPU utilization, results show that KVM is more efficient than Xen on average at 11.5% and 11% respectively. While TripleDES cryptographic algorithm shows a more efficient time response at Xen hypervisor than KVM.
Abdulrazzaq, Mohammed Abdulraoof,Kadhim, Zeyad D.,Faleh, Nadhim M.,Moustafa, Nader M. Techno-Press 2020 Structural monitoring and maintenance Vol.7 No.1
Dynamic stability of graded nonlocal nano-dimension plates on elastic substrate due to in-plane periodic loads has been researched via a novel 3- unknown plate theory based on exact position of neutral surface. Proposed theory confirms the shear deformation effects and contains lower field components in comparison to first order and refined 4- unknown plate theories. A modified power-law function has been utilized in order to express the porosity-dependent material coefficients. The equations of nanoplate have been represented in the context of Mathieu-Hill equations and Chebyshev-Ritz-Bolotin's approach has been performed to derive the stability boundaries. Detailed impacts of static/dynamic loading parameters, nonlocal constant, foundation parameters, material index and porosities on instability boundaries of graded nanoscale plates are researched.
A Multi Levels Data Fusion Approach for an Electric Wheelchair Control
Fatma Ben Taher,Nader Ben Amor,Mohamed Jallouli,Aicha Ben Hammouda,Olfa Dghim 대한의용생체공학회 2016 Biomedical Engineering Letters (BMEL) Vol.6 No.4
Purpose Assistive technology has allowed providing valuableassistance to people with special needs. Several studies havetargeted “smart” wheelchairs. However, these prototypes arenot yet commercialized, mainly for security reasons. Theobjective of this study is to ameliorate the control successrate and fulfill maximally the security constraint. Methods In this paper, we present a multi-levels data fusiontechnique. Three subsystems operate separately to find thenavigation command. These subsystems are based respectivelyon EEG signals, head position tracking and eye tracking. Their individual decisions are then fused to deliver the finalcommand to the wheelchair. Results The proposed technique achieves was able to reacha success rate equal to 94.4%. This rate represents animprovement of 7% compared to single source controltechniques. Conclusions The results of this study demonstrate the abilityof data fusion to improve the success rate and to avoidcritical situations such as total breakdown in case of sensorfailure.
Assessment of stability of early loaded nano-coated hydroxyapatite implants in posterior maxilla
Ola Abdelsamad Amin,Ingy Mohamed Shehata,Heba Mohamed Kamel,Nader Nabil Elbokle 대한치과이식임플란트학회 2024 The Korean Academy of Implant Dentistry Vol.43 No.1
Purpose: This study assessed the stability of nano-coated hydroxyapatite implants in the posterior maxilla after early loading. Materials and Methods: This study was conducted on nine patients missing at least one maxillary posterior tooth. Ten nano-coated hydroxyapatite implants were inserted in nine patients and subjected to early loading according to the secondary stability readings taken by Osstell®. The implant stability was measured at the time of implant insertion (T0), 4 (T1), 6 (T1 modified), weeks, and four months (T2) after surgery. Cone-beam computed tomography (CBCT) was performed in all patients before treatment started. Nine implants healed well, but one implant failed due to infection. Results: The secondary stability results six weeks after implant insertion were sufficient for implant loading. Significant differences were observed between T0, T1, T1 modified, and T2. Conclusions: Nano-coated hydroxyapatite implants are a good choice in the posterior maxilla because they allow early loading.