Heat transfer characteristics and entropy generation for wing-shaped-tubes with longitudinal external fins in cross-flow

Sayed Ahmed E. Sayed Ahmed,Osama M. Mesalhy,Mohamed A. Abdelatief 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

A numerical study is conducted to clarify heat transfer characteristics, effectiveness and entropy generation for a bundle of wingshaped-tubes attached to Longitudinal fins (LF) at downstream side. The air-side Re a ranged from 1.8 x 10 3 to 9.7 x 10 3 . The fin height (h f ) and fin thickness (δ) have been changed as: (2 mm ≤ h f ≤ 12 mm) and (1.5 mm ≤ δ ≤ 3.5 mm). The analysis of entropy generation is based on the principle of minimizing the rate of total entropy generation that includes the generation of entropy due to heat transfer and friction losses. The temperature field around the wing-shaped-tubes with (LF) is predicted using commercial CFD FLUENT 6.3.26 software package. Correlations of Nu a , St a , and Bejan number (Be), as well as the irreversibility distribution ratio (Φ) in terms of Re a and design parameters for the studied bundle are presented. Results indicated that, installing fins with heights from 2 to 12 mm results in an increase in Nu a from 11 to 36% comparing with that of wing-shaped tubes without fins (NOF). The highest and lowest values of effectiveness (ε) at every value of the considered Re a range are occurred at h f = 6 mm and (NOF), respectively. The wing-shaped-tubes heat exchanger with h f = 6 mm has the highest values of (ε), efficiency index (η) and area goodness factor (G a ) and also the lowest values of Φ and hence the best performance comparing with other arrangements. The minimum values of Φ are occurred at h f = 6 mm. (Be) decreases with increasing Re a for all studied h f . The heat transfer irreversibility predominates for (1800 ≤ Re a ≤ 4200) while the opposite is true for (6950 < Re a ≤ 9700). δ has negligible effect on Nu a and heat transfer irreversibility. Comparisons between the experimental and numerical results of the present study and those, previously, obtained for similar available studies showed good agreements.

Determining Dimensions of Job Satisfaction among Employees: Evidence from Commercial Bank Industries in Bangladesh

Md. Sayed UDDIN(Md. Sayed UDDIN ),Md. Atikur RAHAMAN(Md. Atikur RAHAMAN ),Wasib Bin LATIF(Wasib Bin LATIF ) 한국유통과학회 2023 The Journal of Asian Finance, Economics and Busine Vol.10 No.2

Since the banking industry relies so heavily on strong customer-staff interactions, measuring employee job satisfaction has become a critical problem. To achieve benefits for both individuals and organizations, it is crucial to foster and ensure employee job satisfaction. The main objective of this study is to determine the influencing factors of employees’ job satisfaction in commercial banks in Bangladesh. This study focused on some significant factors such as employee empowerment, job security, management support, and attractive compensation in an organization. In terms of research purpose, non-probability convenience sampling has been used, and the study is quantitative in nature. For data collection purposes, an online survey questionnaire was prepared based on previously published articles. The targeted population was the bank employees of commercial banks in Bangladesh where the final sample size was n = 200. For analyzing the collected data, SPSS 26.0 version has been used to test the study model and the proposed hypotheses. This study also shows that employee empowerment, job security, management support, and attractive compensation have positive and significant effects on employees’ job satisfaction at the workplace. Finally, this study has offered some extraordinary directions and implications for future research on commercial bank authorities in Bangladesh.

Bisphosphonate’s effect on the tongue in adult male albino rats and the possible protective role of rutin: light and scanning electron microscopic study

Dalia El-sayed El-ghazouly(Dalia El-sayed El-ghazouly ),Rania Ibrahim Yassien(Rania Ibrahim Yassien ) 대한해부학회 2024 Anatomy & Cell Biology Vol.57 No.1

Alendronate sodium (ALS) is a nitrogen-containing bisphosphonate used for the treatment of different bone disorders. However, its adverse effect on oral soft tissue has been detected. Rutin (RUT) is natural flavonoid with antioxidant and anti-inflammatory properties. This work aimed to investigate the possible effect of ALS on the tongue of adult male albino rats and to evaluate the possible protective role of RUT. Forty adult male albino rats were equally divided into four groups: group I (control), group II (RUT): Received RUT 50 mg/kg, group III (ALS): Received ALS 1 mg/kg, group IV (ALS+RUT): Received ALS and RUT with the same doses as pervious groups. The drugs were given once daily for 5 weeks. Tongue specimens were taken and processed for light and scanning electron microscopic inspection. ALS treated group revealed structural changes in the tongue in the form of decrease in the height of the filiform papillae with blunt ends, marked atrophy in some papillae with areas of focal loss, loss of some epithelial cells, pyknotic nuclei and cytoplasmic vacuoles in some epithelial cells. The lamina propria showed inflammatory cellular infiltration with congested blood vessels. Statistically, there were highly significant decrease in the number of proliferating cell nuclear antigen immunopositive cells, area percentage of Bcl-2 immunoexpression and highly significant increase in the collagen content compared to control group. Administration of RUT with ALS minimizes these changes. RUT protected the rat tongue against the histological and immunohistochemical changes induced by ALS through its antioxidant and anti-inflammatory properties.

Alleviation of salt stress in  Triticum aestivum by biopriming with  Phanerochaete chrysosporium

Hanan El-Sayed Dief,El-Sayed A. Hashem,Salwa Fawzan,Ashraf S. A. El-Sayed 한국작물학회 2021 Journal of crop science and biotechnology Vol.24 No.1

Wheat is one of the most important cereals, vital basic crop in Egypt, covering approximately 32.6% of the total winter land. However, sensitivity to abiotic stress especially salinity is one the major current hurdles that reduce the global yield of this crop. Plant biopriming with fungi is the recent technology that might alleviate the salt stress eff ect. Thus, the objective of this work was to examine the eff ect of Triticum aestivum grains biopriming with Phanerochaete chrysosporium on the response of wheat to salt stress. From the physiological and biochemical parameters, biopriming of wheat grains with P. chrysosporium significantly alleviates the salt stress and markedly increases the growth parameters, photosynthetic pigments and osmolytes (soluble sugars, soluble protein and proline) contents. In addition, it alleviates the oxidative damage, as indicated by the lower accumulation of malondealdehyde and increasing the activity of antioxidant enzymes; superoxide dismutase, catalase, and ascorbate peroxidase in wheat seedlings. Results indicate the potential of using P. chrysosporium biopriming for reducing the deteriorating eff ects of salinity.

Separation axioms in (L,M)-fuzzy topology (L,M)-fuzzy convexity spaces

Osama Rashed Sayed,EL-Sayed EL-Sanousy,Yaser Hassanein Ragheb Sayed 원광대학교 기초자연과학연구소 2021 ANNALS OF FUZZY MATHEMATICS AND INFORMATICS Vol.21 No.1

In this paper, we dene r-L-fuzzy closed convex sets and r-L-fuzzy closed neighbourhoods in an (L, M)-fuzzy topology (L, M)-fuzzy convexity spaces. Also, r-L-fuzzy neighbourhood separation properties r- L-FNSi were studied where i = f0, 1, 2, 3, 4g. In addition, we also study the invariance or otherwise of these separation properties under subspace and product.

Digital Game-Based Learning for Remedial Mathematics Students : A New Teaching and Learning Approach in Malaysia

Sayed Yusoff Syed Hussain,Wee Hoe Tan,Muhammad Zaffwan Idris 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.11

This paper presents a game-based learning study in Malaysia in which a game has been designed for remedial Mathematics students at primary school level. Mathematics is a core subject taught in all primary schools in Malaysia. However, for students who are recognized as weak in Mathematics, teachers use remedial modules supplied by the Ministry of Education in teaching and learning activities. A research study has been initiated to propose digital game-based learning for the remedial students, aiming to enhance the effectiveness of the modules. A prototype game is designed to be playable on tablet computers. The game contains lessons under the title of Whole Numbers: Addition in Year Two syllabus. This paper reveals the concepts and rationale behind the study and the game design. The research plan is also included to justify the ecological validity of the study.

Immune Defense of Rats Immunized with Fennel Honey, Propolis, and Bee Venom Against Induced Staphylococcal Infection

Sayed, S.M.,El-Ella, Ghada A. Abou,Wahba, Nahed M.,Nisr, Neveen A. El,Raddad, Khaled,Rahman, M.F. Abd El,Hafeez, M.M. Abd El,Aamer, Ahmed Abd El Fattah The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

The objective of this work was to evaluate the potency of bee product-immunized rats to overcome an induced Staphylococcus aureus infection. Forty rats were divided to eight groups: T1, T3, and T5 received, respectively, fennel honey, ethanol, and aqueous propolis extracts orally, and T2, T4, and T6 were administered the respective materials intraperitoneally; T7 received bee venom by the bee sting technique; and T8 was the control group. All groups were challenged by a bovine clinical mastitis isolate of S. aureus. Each rat received 2mL of broth inoculated with $1{\times}10^5$ colony-forming units/mL intraperitoneally. Two weeks post-induced infection all rats were sacrificed and eviscerated for postmortem inspection and histopathological study. Three rats from T8 and one rat from T7 died before sacrifice. Another two rats, one each in T4 and T5, had morbidity manifestations. The remaining experimental animals showed apparently healthy conditions until time of sacrifice. Postmortem inspection revealed that all T8 rats showed different degrees of skeletal muscle and internal organ paleness with scattered focal pus nodules mainly on lungs and livers. All rats of the treated groups showed normal postmortem features except three rats. A dead rat in group T7 showed focal pus nodules on the lung surface only, whereas the affected two rats in groups T4 and T5 appeared normal except with some pus nodules, but much smaller than in the control, scattered on the hepatic surface and mesentery. Histopathological studies revealed that T8 rats had typical suppurative bronchopneumonia and or severe degenerative and necrobiotic changes in hepatic tissues. Three affected rats of the treated groups showed slight bronchopneumonia or degenerative hepatic changes only. The other animals of the treated groups showed completely normal parenchymatous organs with stimulated lymphatic tissues. It was concluded that all tested previously bee product-immunized rats could significantly challenge the induced S. aureus infection (P < .01). The effects were more pronounced in rats that had received fennel honey solution.

Application of Taguchi method in optimization of process parameters of ODS tungsten heavy alloys

Sayed, Mohamed A.,Dawood, Osama M.,Elsayed, Ayman H.,Daoush, Walid R. Techno-Press 2017 Advances in materials research Vol.6 No.1

In the present work, a design of experiment (DOE) technique using Taguchi method, has been applied to optimize the properties of ODS tungsten heavy alloys(WHAs). In this work Taguchi method involves nine experiments groups for four processing parameters (compaction pressure, sintering temperature, binding material type, and oxide type) with three levels was implemented. The signal-to-noise (S/N) ratio and analysis of variance (ANOVA) were employed to obtain the optimal process parameter levels and to analyze the effect of these parameters on density, electrical conductivity, hardness and compressive strength values. The results showed that all the chosen factors have significant effects on all properties of ODS tungsten heavy alloys samples. The density, electrical conductivity and hardness increases with the increase in sintering temperature. The analysis of the verification experiments for the physical properties (density and Electrical conductivity) has shown that Taguchi parameter design can successfully verify the optimal parameters, where the difference between the predicted and the verified values of relative density and electrical conductivity is about 1.01% and 1.15% respectively.

The effect of microfinance on women’s empowerment : Evidence from Malaysia

Sayed Samer Ali AL-SHAMI,Muhammad M. RAZALI,Izaidin MAJID,Ahmed ROZELAN,Nurulizwa RASHID 이화여자대학교 아시아여성학센터 2016 Asian Journal of Women's Studies(AJWS) Vol.22 No.3

Microfinance is widely known as a financial development tool for those deprived of access to financial services, especially women. However, the literature provides conflicting evidence and shows that women’s empowerment may not, or may only be partially achieved through microcredit, especially in Muslim societies. This study seeks to scrutinize the effect of Amanah Ikhtiar Malaysia (AIM), a microcredit institution, on Malay Muslim women in an urban area. A quasi-experimental method was used to conduct a cross sectional survey of 500 old and new clients. Informal semi-structured interviews were conducted with 20 current clients who had received microcredit two years earlier. The findings show that AIM microcredit empowered the women and enhanced gender equality. It enabled women to access financial capital, form their micro- and smallbusinesses and obtain an income which helped them to contribute to household expenditure. Even though the effect of microcredit was partial, it provided them bargaining power for decision-making and controlling of resources and enhanced their self-esteem in their households and communities. Pembiayaan mikro secara meluasnya dikenali sebagai kaedah membangunkan mereka yang tidak diberi peluang akses perkhidmatan kewangan lain, khasnya di kalangan golongan wanita. Walau bagaimanapun, literatur kajian lampau telah mengemukakan bukti yang bercanggah di mana pembiayaan mikro kepada golongan wanita terutamanya mereka dalam masyarakat Islam mungkin tidak langsung atau mungkin sebahagiannya sahaja memberi kesan terhadap kejayaan mereka. Kajian ini bertujuan untuk meneliti kesan Amanah Ikhtiar Malaysia (AIM) iaitu sebuah institusi pembiayaan mikro, di kalangan wanita Melayu Islam di kawasan bandar. Satu kaedah kuasieksperimen telah digunakan untuk menjalankan kajian terhadap 500 pelanggan lama dan baru pembiayaan mikro. Temubual informal separa berstruktur telah dijalankan bersama 20 pelanggan yang sedang menerima pembiayaan mikro dalam tempoh dua tahun sebelumnya. Hasil kajian menunjukkan bahawa pembiayaan mikro AIM menjadikan wanita bertambah berjaya dan dapat menyumbang terhadap kesamarataan antara gender. Ia membolehkan mereka memperolehi modal, membentuk perniagaan mikro atau kecil dan seterusnya memperolehi pendapatan yang dapat membantu mereka untuk menyumbang kepada perbelanjaan isi rumah. Walaupun kesan pembiayaan mikro ini menyumbang kepada sebahagian sahaja peningkatan ini, namun ia dapat menyediakan mereka kuasa tawar-menawar untuk membuat keputusan, kawalan ke atas sumber dan meningkatkan keyakinan diri golongan ini.

Enhancing antifouling and separation characteristics of carbon nanofiber embedded poly ether sulfone nanofiltration membrane

Sayed Mohsen Hosseini,Mansoureh Sadat Banijamali,Samaneh Koudzari Farahani,Samaneh Bandehali 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.9

Poly (ether sulfone)-(PES) based mixed-matrix nanofiltration (NF) membranes were fabricated by incorporatingcarbon nanofibers (CNFs) through solution casting technique. Scanning optical microscopy (SOM), scanningelectron microscopy (SEM) and surface roughness analysis were carried out in membrane characterization. Wateruptake, contact angle, tensile strength, and porosity measurements, as well as water flux, salt rejection and antifoulingexperiments were used. SEM images showed more porous structure for the blended membranes compared to virginmembrane. Finger-like pores was also observed for the modified membranes. SOM image showed uniform surface forthe prepared membranes relatively. Surface roughness also showed decreasing trend by increase of CNF ratio. Watercontact angle was reduced from 67.8o for pristine membrane to 54.6o for the blended membranes. Salt rejection alsoincreased from 66.49% for bare membrane to 86.4% for the blended membrane containing of 0.1 wt% CNFs. Themembrane porosity, water content, water flux and tensile strength were enhanced by using CNFs into the membranebody. Blended PES-CNFs membranes showed high fouling resistance compared to the virgin membrane. The fluxrecovery ratio was measured up to 79.20% for the modified membranes.