http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ramadan N. Elshaer,Mohamed K. El‑Fawakhry,Ahmed I. Z. Farahat 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.6
The effect of quenching after martensitic finish (QAMf) or quenching & partitioning (Q&P) on microstructure evolution,mechanical properties, and strain hardening instability of low and medium carbon hot rolled steels were investigated. Twoheats of low and medium carbon steels were cast in an induction open furnace. The chemical composition of low carbonsteel is 0.16C–0.27Si–1.47Mn–0.02Al while medium carbon steel is 0.49C–0.30Si–0.91Mn–0.03Al. They were hot-rolledat 1200 °C for 30 min followed by air cooling. The microstructure after hot-rolled gives bands of ferrite and pearlite for0.16 wt% low carbon steel. On the other hand, 0.49 wt% medium carbon steel produces coarse pearlite islands surrounded byferrite phase. To enhance mechanical properties, it was necessary to modify the microstructure of low and medium carbonsteels using QAMfor Q&P processes. The resultant matrix of microstructure after QAMfand Q&P processes containedferrite, bainite, lath martensite, and retained austenite for 0.16 wt% low carbon steel, and polygonal ferrite, lath martensite,and retained austenite for 0.49 wt% medium carbon steel, respectively. In low carbon steel, QAMfprocess increased uniformelongation from 6.6 to 13.5% (105% increase) while ultimate tensile strength (UTS) improved slightly from 645 to 692 MPa(7% increase). However, in medium carbon steel, Q&P reduced uniform elongation from 12.4 to 4.8% (61% decrease) whileincreased UTS from 769 to 1242 MPa (61.5% increase). It is worthy to mention that QAMfprocess exhibited strain hardeninginstability zone (7.8% strain before necking) compared to hot-rolled process (0% strain before necking). On the otherhand, Q&P process highly decreased strain hardening instability zone (0.77% strain before necking) compared to hot-rolledprocess (3.4% strain before necking).
Amal G. Ramadan(Amal G. Ramadan ),Ahmed A. M. Yassein(Ahmed A. M. Yassein ),Eissa A. Eissa(Eissa A. Eissa ),Gamal M. Hassan(Gamal M. Hassan ) 한국축산식품학회 2022 Food and Life Vol.2022 No.3
Zinc oxide nanoparticles (ZnO-NPs) are regularly utilized in the food and fertilizers industries. In our investigation, rats received oral administration of ZnO NPs with a particle size of 30±5 nm once daily at doses of 100, 200, 300, 400, and 600 mg/kg for ten weeks in order to assess the genotoxic effect. Impacts on hematological markers, genotoxic impact, and growth were investigated. The findings showed that ZnO-NPs significantly reduced body weight gain, red blood cell count (RBC), hemoglobin concentration (Hb), hematocrit value (HCT), and platelet count (PLT), while increasing white blood cell (WBC), mean capsular volume (MCV), mean capsular hemoglobin (MCH), and mean capsular hemoglobin concentration (MCHC) in the treated rats. Our results for the comet assay and micronuclei test show a dosage-dependent increase in DNA fragmentation, which was supported by an increase in the percentage of DNA that is tailed, the length and intensity of DNA tails, and the tail moment, especially at the dose of 600 mg/kg. According to the findings, the frequency of micronucleated cells has increased.
SUPRA FUZZY CONVERGENCE OF FUZZY FILTERS
Ramadan, A.A.,El-Latif, A.A. Abd Korean Mathematical Society 2008 대한수학회보 Vol.45 No.2
We introduce and study the notions of supra fuzzy convergence of fuzzy filters, $s{\gamma}$-fuzzy open (closed) sets, $s{\gamma}($s{\gamma}^*)$-fuzzy continuous and $s{\gamma}$-fuzzy open mapping. Also. we investigate some of fundamental properties of these notions.
Ramadan, A.A.,Abdel-Sattar, M.A.,Kim, Yong-Chan Korean Mathematical Society 2002 대한수학회보 Vol.39 No.4
In this paper, we study some properties of fuzzy interior spaces. Also, we investigate the relations between fuzzy interior spaces and fuzzy topological spaces. In particular, we prove the existence of product fuzzy topological spaces and product fuzzy interior spaces. We investigate the relations between them.
Smooth neighborhood structures
Ramadan, A.A.,Kim, Y.C.,El-Gayyar, M.M. Korean Institute of Intelligent Systems 2002 한국지능시스템학회논문지 Vol.12 No.2
In this paper, we introduce the notion of smooth neighborhoods in smooth topological spaces and investigate some of their properties. In particular, we can obtain some smooth topologies from a smooth neighborhood system.
Ramadan, A.A.,El-Dardery, M.,Kim, Y.C. Korean Institute of Intelligent Systems 2002 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.2 No.1
We study some properties of smooth uniform spaces. We investigate the relationship between smooth topological spaces and smooth uniform spaces. In particular, we define a subspace of a smooth uniform space and a product of smooth uniform spaces.
Ramadan S. Tantawi 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.9
The influence of the initial stress and the Hall current on a two-temperature thermoelastic material is investigated in the framework of the modified Ohm’s law and Green-Naghdi theory. Analytical expressions for the physical quantities are obtained by using the normal mode method and are presented graphically. Finally, the resulting physical quantities are discussed with and without the initial stress and the Hall current. The results of this study have applications in a wide range of physical problems, geophysical applications, and radiation physics.
Study on the Coupled Effects of Process Parameters on Silicon Growth Using Chemical Vapor Deposition
Ramadan, Zaher,Ko, Dong Kuk,Im, Ik-Tae The Korean Society Of SemiconductorDisplay Technol 2019 반도체디스플레이기술학회지 Vol.18 No.3
Response surface methodology (RSM) is used to investigate the complex coupling effects of different operating parameters on silicon growth rate in planetary CVD reactor. Based on the computational fluid dynamics (CFD) model, an accurate RSM model is obtained to predict the growth rate with different parameters, including temperature, pressure, rotation speed of the wafer, and the mole fraction of dichlorosilane (DCS). Analysis of variance is used to estimate the contributions of process parameters and their interactions. Among the four operating parameters that have been studied, the influences of susceptor temperature and the operating pressure were the most significant factors that affect silicon growth rate, followed by the mole fraction of DCS. The influence of wafer rotation is the least. The validation tests show that the results of silicon deposition rate obtained from the regression model are in good agreement with those from CFD model and the maximum deviations is 2.15%.
ON FUZZY BITOPOLOGICAL SPACES IN ŠOSTAK'S SENSE (II)
Ramadan, Ahmed Abd El-Kader,Abbas, Salah El-Deen,El-Latif, Ahmed Aref Abd Korean Mathematical Society 2010 대한수학회논문집 Vol.25 No.3
In this paper, we have use a fuzzy bitopological space (X, $\tau_1$, $\tau_2$) to create a family $\tau_{ij}^s$ which is a supra fuzzy topology on X. Also, we introduce and study the concepts of r-($\tau_i$, $\tau_j$)-generalized fuzzy regular closed, r-($\tau_i$, $\tau_j$)-generalized fuzzy strongly semi-closed and r-($\tau_i$, $\tau_j$)-generalized fuzzy regular strongly semi-closed sets in fuzzy bitopological space in the sense of $\check{S}$ostak. Also, these classes of fuzzy subsets are applied for constructing several type of fuzzy closed mapping and some type of fuzzy separation axioms called fuzzy binormal, fuzzy mildly binormal and fuzzy almost pairwise normal.