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Intersecting Sanctuaries: Exploring Cultural Hybridity at Córdoba's Mosque-Cathedral

  • Soojeong YI
    • Acta Via Serica
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    • v.9 no.1
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    • pp.139-160
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    • 2024
  • This study delves into the concept of cultural hybridity, using the Great Mosque-Cathedral in Córdoba, Spain as a unique case study. This monumental site stands as a testament to the convergence of Islamic and Christian architecture and ideology, a phenomenon that is often discussed in modern contexts. However, this study takes a step further, examining cultural hybridity across historical epochs to reveal its persistent relevance in shaping social and cultural landscapes. Originally a mosque transformed into a Christian cathedral, the Great Mosque-Cathedral is a prime example of this phenomenon, reflecting continuous cultural, architectural, and ideological exchanges between the two religions. This paper meticulously analyzes how the structure's architectural elements embody these exchanges, such as its ornate mihrab and unique double-arched columns. By integrating theories of hybridity with a detailed architectural and historical analysis, the study argues that the mosque-cathedral is not merely a physical space but a dynamic medium through which cultural negotiations and adaptations are articulated. The findings underscore the complexity of cultural hybridity, challenging simplistic interpretations of cultural exchange and dominance, and highlighting the mosque-cathedral's role in ongoing debates about identity and heritage in contemporary society. This comprehensive examination contributes to academic discussions on hybridity and enhances our understanding of cultural resilience and transformation through architectural spaces.

A two-stage Kalman filter for the identification of structural parameters with unknown loads

  • He, Jia;Zhang, Xiaoxiong;Feng, Zhouquan;Chen, Zhengqing;Cao, Zhang
    • Smart Structures and Systems
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    • v.26 no.6
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    • pp.693-701
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    • 2020
  • The conventional Kalman Filter (KF) provides a promising way for structural state estimation. However, the physical parameters of structural systems or models should be available for the estimation. Moreover, it is not applicable when the loadings applied to the structures are unknown. To circumvent the aforementioned limitations, a two-stage KF with unknown input approach is proposed for the simultaneous identification of structural parameters and unknown loadings. In stage 1, a modified observation equation is employed. The structural state vector is estimated by KF on the basis of structural parameters identified at the previous time-step. Then, the unknown input is identified by Least Squares Estimation (LSE). In stage 2, based on the concept of sensitivity matrix, the structural parameters are updated at the current time-step by using the estimated structural states obtained from stage 1. The effectiveness of the proposed approach is numerically validated via a five-story shearing model under random and earthquake excitations. Shaking table tests on a five-story structure are also employed to demonstrate the performance of the proposed approach. It is demonstrated from numerical and experimental results that the proposed approach can be used for the identification of parameters of structure and the external force applied to it with acceptable accuracy.

Artificial Control of ZnO Nanorods via Manipulation of ZnO Nanoparticle Seeds (산화아연 나노핵의 조작을 통한 산화아연 나노로드의 제어)

  • Shin, Kyung-Sik;Lee, Sam-Dong;Kim, Sang-Woo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.399-399
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    • 2008
  • Synthesis and characterization of ZnO structure such as nanowires, nanorods, nanotube, nanowall, etc. have been studied to multifunctional application such as optical, nanoscale electronic and chemical devices because it has a room-temperature wide band gap of 3.37eV, large exiton binding energy(60meV) and various properties. Various synthesis methods including chemical vapor deposition (CVD), physical vapor deposition, electrochemical deposition, micro-emulsion, and hydrothermal approach have been reported to fabricate various kinds of ZnO nanostructures. But some of these synthesis methods are expensive and difficult of mass production. Wet chemical method has several advantage such as simple process, mass production, low temperature process, and low cost. In the present work, ZnO nanorods are deposited on ITO/glass substrate by simple wet chemical method. The process is perfomed by two steps. One-step is deposition of ZnO seeds and two-step is growth of ZnO nanorods on substrates. In order to form ZnO seeds on substrates, mixture solution of Zn acetate and Methanol was prepared.(one-step) Seed layers were deposited for control of morpholgy of ZnO seed layers by spin coating process because ZnO seeds is deposited uniformly by centrifugal force of spin coating. The seed-deposited samples were pre-annealed for 30min at $180^{\circ}C$ to enhance adhesion and crystallinnity of ZnO seed layer on substrate. Vertically well-aligned ZnO nanorods were grown by the "dipping-and-holding" process of the substrates into the mixture solution consisting of the mixture solution of DI water, Zinc nitrate and hexamethylenetetramine for 4 hours at $90^{\circ}C$.(two-step) It was found that density and morphology of ZnO nanorods were controlled by manipulation of ZnO seeds through rpm of spin coating. The morphology, crystallinity, optical properties of the grown ZnO nanostructures were carried out by field-emission scanning electron microscopy, high-resolution electron microscopy, photoluminescence, respectively. We are convinced that this method is complementing problems of main techniques of existing reports.

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Application of Bayer-Villiger Reaction to the Synthesis of Dibenzo-18-crown-6, Dibenzo-21-crown-7 and Dihydroxydibenzo-18-crown-6

  • Utekar, Druman R.;Saman, Shriniwas D.
    • Journal of the Korean Chemical Society
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    • v.58 no.2
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    • pp.193-197
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    • 2014
  • Dibenzo-18-crown-6, dibenzo-21-crown-7 and dihydroxy dibenzo-18-crown-6 were synthesized by Bayer-Villiger oxidation strategy. Dibenzo-18-crown-6 and dibenzo-21-crown-7 could be synthesized through a three-step protocol starting from salicylaldehyde. Salicylaldehyde was reacted with bis-(2-chloroethyl)ether using $K_2CO_3$ in acetonitrile to link the two phenolic groups with the oxyethylene bridge followed by conversion of the formyl group to the hydroxy group via a Baeyer-Villiger reaction and finally linking the two phenolic group with appropriate oxyethylene bridge. The two target crown ethers were obtained in overall yield, 24% and 30%, respectively. This method has a great potential for synthesis of symmetrical as well as unsymmetrical dibenzo crowns with varying oxyethylene bridges. Baeyer-Villiger oxidation could be used to prepare dihydroxy derivative of dibenzo-18-crown-6 through acetylation of dibenzo-18-crown-6 followed by Baeyer-Villiger oxidation. The Baeyer-Villiger oxidation could be substantially accelerated using trifluoroacetic acid.

Performance Evaluation of a Quarter Car Suspension System Installed with MR Damper Featuring Bypass Flow Holes in Piston (피스톤 바이패스 유로가 있는 MR 댐퍼 장착 1/4 차량 현가시스템의 성능평가)

  • Kim, Wan Ho;Hwang, Yong Hoon;Park, Jhin Ha;Shin, Cheol-Soo;Choi, Seung-Bok
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.27 no.1
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    • pp.65-71
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    • 2017
  • This work presents a comparative work on the ride comfort of a quarter car suspension system between two different magneto-rheological (MR) dampers; one is conventional type without bypass hole and the other is featured by several bypass holes in the piston. As a first step, two different MR dampers are designed on the basis of the governing equation and manufactured with same geometric dimensions except the bypass holes. After investigating the field-dependent damping properties, two dampers are installed to the quarter car suspension system. The suspension model is then derived and a sky-hook controller is implemented to identify vibration control performance under random road. It is shown that the suspension system with MR damper featured by the bypass holes can provide much better ride quality than the case without the bypass holes. This is validated via experimental implementation.

Nonlinear numerical model of headed shear stud anchors for composite open web steel joists

  • Yanez, Sergio J.;Dinehart, David W.;Pina, Juan Carlos;Guzman, Carlos Felipe
    • Steel and Composite Structures
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    • v.44 no.4
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    • pp.545-555
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    • 2022
  • Empirical relationships that capture the nonlinear behavior of headed steel shear stud anchors have been derived from standard push out tests, where the specimens are comprised of large wide flanged steel sections attached to flat concrete slabs via the anchors. However, many composite systems used in practice utilize much smaller steel members and/or steel decking as part of the slab system. Composite open web steel joist systems generally include both of these elements and consequently the nonlinear performance ofthe anchor is not accurately represented by existing models. In this paper, a new empirical relation is presented for open web steel joist systems based on experimental results from a modified push out test that more realistically represent a composite open web steel joist system. The methodology for obtaining the proposed nonlinear function where the response of the system is characterized by two parameters(α and β) is presented. The two-step process for obtaining the two parameters is described and the empirical relation is calibrated with the experimental data. In comparison with existing expressions, the new proposal herein more accurately predicts the high initialstiffness of the system and overall nonlinear system performance.

Kinetics of the Thermal Decomposition of Mg-Al Sulfate Hydrate (Mg-Al 복합 황산염 수화물의 열분해 속도)

  • 박홍채;오기동
    • Journal of the Korean Ceramic Society
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    • v.24 no.5
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    • pp.417-422
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    • 1987
  • Kinetic studies were made on the thermal decomposition of hydrated magnesium aluminum double sulfate by a nonisothermal TG method. Thermal analyses of the dehydration of tricosahydrate showed that the reaction proceeded via decahydrate to the anhydrous MgAl2(SO4)4 in the range 50$^{\circ}$to 400$^{\circ}C$. Decomposition of MgAl2(SO4)4 occurred as the two-step between 650$^{\circ}$ and 970$^{\circ}C$. Dehydration of MgAl2(SO4)4$.$23H2O and a 2D diffusion controlled with an activation energy of 16.6kcal/mole, respectively. MgAl2(SO4)4 fitted the contracting volume model with an activation energy of 10.5kcal/mole, and MgSO4 fitted a contracting area model with an activation of 4.5kcal/mole.

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Synthesis and Characterization of Novel Aromatic Polyimides from Bis (3-aminophenyl) 3,5-bis (trifluorormethyl) phenyl Phosphine Oxide

  • Jeong, Kwang-Un;Kim, Jang-Joo;Yoon, Tae-Ho
    • Macromolecular Research
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    • v.8 no.5
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    • pp.215-223
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    • 2000
  • A novel diamine monomer, containing fluorine and phosphine oxide, bis(3-aminophenyl) 3,5-bis(trifluoromethyl)phenyl phosphine oxide (mDA6FPPO), was prepared via Grignard reaction, and utilized to prepare polyimides with dianhydrides such as PMDA, 6FDA, BTDA or ODPA, by the conventional two-step route; preparation of poly(amic acid), followed by solution imidization. The polyimides were characterized by FT-IR, NMR, and DSC with intrinsic viscosity and refractive index also being evaluated. A phosphine oxide containing monomer, bis(3-aminophenyl)phenyl phosphine oxide (mDAPPO) and a commercial 3,3-diaminodiphenyl sulfone (mDDS) were also used for comparison. The polyimides derived from mDA6FPPO exhibited high T$\sub$g/, excellent solubility and low birefringence.

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Characterizations of nitrided gate oxides by fowler-nordheim tunneling electron injection (Fowler-nordheim 터널링 전자주입에 의한 질화 게이트 산화막의 특성 분석)

  • 장성수;문성근;노관종;노용한;이칠기
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.7
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    • pp.79-87
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    • 1998
  • Nitrided oxides which have been investigated as alternative gate oxide for metal-oxide-semiconductor field effect devices were grown by two-step process using N$_{2}$O gas, and were chaacterized via a fowler-nordheim tunneling(FNT) electron injection technique. Electrical characteristics of nitrided gate oxides were superior to that of control oxides.Further, the FNT electron injection into the nitrided gate oxides reveals that gate oxides degrade more both if electrons were foreced to inject from the gate metal and if thicker nitrided gate oxides were used in the thickness range of 90~130.angs.. Models are suggested to explain these phenomena.

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Anisotropic Superomniphobic Wettability on Hierarchical Structures of Micro Line Array Combined with Fluorinated Wax (C24F50)

  • Jeon, Deok-Jin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.209.2-209.2
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    • 2014
  • In recent years, researches about hydrophobic and hydrophilic surfaces have been executed however their other effects have not been researched enough. In this paper, the fabrication method of hierarchical structures of micro line array combined with fluorinated wax for anisotropic superomniphobic wettability is presented. We have achieved anisotropic and superomniphobic surface via simple two step methods, which are maskless photolithography and wax deposition. In order to prove how to provide those characteristics, SEM, contact angle measurement tool and X-ray diffraction are used. Fluorinated wax is crystalized self-assembly and it is subordinated on micro line array so that it is able to display anisotropic wettability. Understanding on anisotropic superomniphobic surface and simple fabrication method has been attracted to apply for lots of applications which range from self-cleaning surface, microfluidic chip, to directionally fluid control device, even in oily fluid.

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