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      • Empathic Modelling for Product Design Engineering Students

        ( Ibrahim,N. I. ) 한국감성과학회 2014 춘계학술대회 Vol.2014 No.-

        This paper explains the use of empathic modelling as a pedagogical tool for Product Design Engineering students. The objective is to expose students to the challenges of being physically impaired when using products. The method that had been used include using low technology props and focusing on simulating people with multiple disabilities. Based on students` responses, it can be concluded that empathic modelling has helped students to gain better understanding the difficulties that older and disabled people usually encounter when carrying out daily tasks. Finally, several issues and challenges related to the use of empathic modelling method are discussed. It is hope that this paper will be valuable for those interested in using empathic modelling in teaching Product Design Engineering.

      • KCI등재

        Ameliorative effect of hesperidin against high dose sildenafil-induced liver and testicular oxidative stress and altered gene expression in male rats

        Ibrahim M. Ibrahim Laila,Samar HassabAllah Kassem,Marwa Salah ElDin Mohamed Diab 한국실험동물학회 2023 Laboratory Animal Research Vol.39 No.3

        Background: The clinical use of sildenafil citrate (Viagra), a drug used to treat erectile dysfunction, is limited because of its many side effects on tissues. In this context, we aimed to investigate the protective effects of hesperidin, a citrus flavonoid, on hepatic and testicular damage induced by a high dose of sildenafil citrate in male rats. Rats were randomly divided into four groups. The first group was used as the control group. The second group was orally administered sildenafil citrate at a high dose of 75 mg/kg thrice a week. In the third group, hesperidin was administered orally at a dose of 50 mg/kg/day. The fourth group was administered 75 mg/kg sildenafil citrate three times a week with 50 mg/kg hesperidin daily. The experiment lasted for 28 days. Results: In the sildenafil-treated groups, blood indices were altered, liver function tests were deranged, and serum testosterone levels were reduced. In the liver and testicular tissue, sildenafil citrate treatment resulted in significant reductions in catalase and total antioxidant capacity; as well as increased malondialdehyde, reactive oxygen species, and nitrous oxide levels. In addition, sildenafil citrate treatment caused abnormal histopathological patterns in both the liver and the testes. Liver vascular endothelial growth factor and testicular steroidogenic acute regulatory protein gene expression were upregulated. Conclusions: Hesperidin attenuated the harmful effects of intensive sildenafil citrate treatment on liver and testicular functions, alleviated oxidative stress and normalized blood indices. Therefore, hesperidin could be protective against sildenafil citrate-induced oxidative damage that may develop over the long term.

      • KCI등재

        Numerical characterization of downburst wind field at WindEEE dome

        Ibrahim Ibrahim,Haitham Aboshosha,Haitham Aboshosha 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.30 No.3

        Downbursts are acknowledged for being a major loading hazard for horizontally-extending structures like transmission line systems. With these structures being inherently flexible, it is important to characterize the turbulence associated with the wind flow of downburst events being essential to quantify dynamic excitations on structures. Accordingly, the current study numerically characterizes the downburst wind field of open terrain simulated at the Wind Engineering, Energy and Environment (WindEEE) dome testing facility at The University of Western Ontario in Canada through a high-resolution large eddy simulation (LES). The study validates the numerical simulation considering both the mean and the turbulent components of the flow. It then provides a detailed visual description of the flow at WindEEE through the capabilities enabled by LES to identify the key factors affecting the flow. The study also presents the spatial distribution of turbulence intensities and length scales computed from the numerical model and compares them with previous values reported in the literature. The comparison shows the ability of the downburst simulated at WindEEE to reproduce turbulence characteristics similar to those reported from field measurements. The study also indicates that downburst turbulence is well-correlated circumferentially which imposes high correlated loads on horizontally-distributed structures such as transmission lines.

      • Challenges and Opportunities for Niger's Economic Development: A Focus on Agriculture and Mining

        Ibrahim Aïchatou(Ibrahim Aïchatou ),Ousmane Mariama(Ousmane Mariama ) 아시아사회과학학회 2023 Jornal of Asia Social Science Vol.10 No.1

        This paper examines the challenges and opportunities for sustainable economic development in Niger, focusing on the agriculture and mining sectors. While agriculture is the mainstay of Niger's economy, it faces challenges such as climate change, low productivity, and lack of infrastructure. The mining sector has great potential, but also faces challenges related to regulation, environmental protection, and social impacts. The government has implemented policies and initiatives to support these sectors and promote sustainable development. The paper identifies key policy options, including revising regulations, improving infrastructure, promoting local content, and implementing social and environmental safeguards. To achieve sustainable and inclusive development, Niger needs to prioritize investments in human capital, social protection, and environmental sustainability, while also promoting private sector engagement and regional integration.

      • Effect of horizontal joints on structural behavior of sustainable self-compacting reinforced concrete beams

        Ibrahim, Omar Mohamed Omar,Heniegal, Ashraf Mohamed,Ibrahim, Khamis Gamal,Agwa, Ibrahim Saad Techno-Press 2020 Advances in concrete construction Vol.10 No.5

        This study investigated the effect of horizontal casting joints on the mechanical properties and structural behavior of sustainable self-compacting reinforced concrete beams (SCRCB). The experimental research consisted of two stages. The first stage used four types of concrete mixtures which were produced to indicate the effects of cement replaced with cement waste at 0%, 5%, 10%, and 15% by weight of cement content on fresh concrete properties of self-compacting concrete (SCC) such as, passing ability, filling ability, and segregation resistance. In addition, mechanical properties such as compressive, tensile, and flexural strength were also studied. The second stage selected the best mixture from the first stage and studied the effect of horizontal casting joints on the structural behavior of sustainable SCRCBs. The effect of horizontal casting joints on the mechanical properties and structural behavior were at the 25%, 50%, 75%, and 100% of sample height. Load deflection, failure mode, and theoretical analysis were studied. Results indicated that the incorporation of replacement with cement waste by 5% to 10% led to economic and environmental advantages, and the results were acceptable for fresh and mechanical properties. The results indicated that delaying the time for casting the second layer and increasing the cement waste in concrete mixtures had a great effect on the mechanical properties of SCC. The ultimate load capacity of horizontal casting joints reinforced concrete beams slightly decreased compared with the control beam. The maximum deflection of casting joint beams with 75% of samples height is similar with the control beam. The experimental results of reinforced concrete beams were substantially acceptable with the theoretical results. The failure modes obtained the best forced casting joint on the structural behavior at 50% height of casting in the beam.

      • KCI등재
      • Intelligent Offline Multi Object Recognition Walking Stick for The Blind

        Ibrahim Mohammed Abdullahi,Olayemi Mikail Olaniyi,Jacob Omokhafe Irefu,Sangwon Oh,Ibrahim Aliyu 한국디지털콘텐츠학회 2021 The Journal of Contents Computing Vol.3 No.2

        Vision is one of the most important characteristics of a human that aid their day to day activities. Loss of vision however affects the ability of humans to freely navigate their environment and recognized objects along their path. Existing object recognition systems for the blind are mostly cloud based and its performance depends on reliable internet access. This makes them unsuitable in places with unreliable internet. Therefore, in this paper, a multi-object recognition intelligent walking stick for the blind that is completely independent of the internet was developed. The system is divided into three units, detection, recognition and communication units. The detection unit make use of an ultrasonic sensor and a buzzer, for informing the user of an impending obstacle. The recognition system makes use of a camera for capturing images with Convolutionary Neural Network architecture and Mobile Network Single Shot Multi-Box Detector (MobileNet SSD) for detecting objects in images. The communication unit transmits the recognised objects through voice to the user in English Language. The entire system was deployed in a Raspberry Pi microcontroller due to its processing power. The result obtained from testing of the device on the field showed that the recognition unit achieved an average sensitivity, specificity, precision and accuracy of 87.26%, 67.45%, 89.07%, 82.50% respectively. This shows that the system is reliable and can be used in recognizing objects for the blind.

      • SCIESCOPUSKCI등재

        Activity and stability of purified amylase produced by streptomyces aureofaciens 77

        Ibrahim, A.N.,Ahmed, F.H.,Ibrahim, M.M.K.,Arafa, M.A.I. The Pharmaceutical Society of Korea 1990 Archives of Pharmacal Research Vol.13 No.1

        The effects of pH values, temperature and some elements on the amylolytic activity and stability of the purified S. aureofacienc 77 amylase were studied in this investigation. The purified enzyme showed its maximum activity at pH 6 within 8 min incubation at $40^{\circ}C$. None of the tested 6 metals showed on stimulatory effect on the enzymatic activity, $Fe^{+++}$, $Cu^{++}$ and $Hg^{++}$ at high dose inhibited the enzyme activity to great extent as compared with $Zn^{++}$, $Mn^{++}$ and $Fe^{++}$ whih gave less effect in this respect. The enzyme liquor was found to be thermolabile, since it lost completely its activity after 4 days incubation under room temperature and showed maximum activity during this period as a result of additions of $Ca^{++}$and NaCl, Gradual reduction was however recorded until activity reached 30% after 60 days of incubation.

      • SCIESCOPUSKCI등재

        Precepitation and purification of amylase enzyme produced by streptomyces aureofaciens 77

        Ibrahim, A.N.,Ahmed, F.H.,Ibrahim, M.M.K.,Arafa, M.A.I. The Pharmaceutical Society of Korea 1990 Archives of Pharmacal Research Vol.13 No.1

        Precipitation and purification of amylase secreted by Streptomyces aureofaciens 77 in liquid inorganic salts-starch medium under the optimum conditions were carried out. Ammonium sulphate fractionation was used to precipitate amylase in cell free culture filtrate. (NH/sub 4/)/sub 2/ SO/sub 4/ at a concentration of 50-70% saturation gave the highest enzyme yield. The obtained precipitates were redissolved in phosphate buffer (pH 7.0) and subjected to dialysis. The dialyzed enzyme preparation was applied to DEAE-cellulose column chromatography which resulted in an increase of purification up to 59.48 fold. A further step of purification was done by applying the obtained purified sample to Sephadex-G200 column chromatography which resulted in ann increase of purification up to 73. 92 fold. The results clearly indicated that the isolated amylase from S. aureofaciens 77 was only on type.

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