• 제목/요약/키워드: Islamic History

검색결과 95건 처리시간 0.023초

Seismic response of RC structures rehabilitated with SMA under near-field earthquakes

  • Shiravand, M.R.;Khorrami Nejad, A.;Bayanifar, M.H.
    • Structural Engineering and Mechanics
    • /
    • 제63권4호
    • /
    • pp.497-507
    • /
    • 2017
  • During recent earthquakes, a significant number of concrete structures suffered extensive damage. Conventional reinforced concrete structures are designed for life-time safety that may see permanent inelastic deformation after severe earthquakes. Hence, there is a need to utilize adequate materials that have the ability to tolerate large deformation and get back to their original shape. Super-elastic shape memory alloy (SMA) is a smart material with unique properties, such as the ability to regain undeformed shape by unloading or heating. In this research, four different stories (three, five, seven and nine) of reinforced concrete (RC) buildings have been studied and subjected to near-field ground motions. For each building, two different types of reinforcement detailing are considered, including (1) conventional steel reinforcement (RC frame) and (2) steel-SMA reinforcement (SMA RC frame), with SMA bars being used at plastic zones of beams and steel bars in other regions. Nonlinear time history analyses have been performed by "SeismoStruct" finite element software. The results indicate that the application of SMA materials in plastic hinge regions of the beams lead to reduction of the residual displacement and consequently post-earthquake repairs. In general, it can be said that shape memory alloy materials reduce structural damage and retrofit costs.

Dynamic response of layered hyperbolic cooling tower considering the effects of support inclinations

  • Asadzadeh, Esmaeil;Alam, Mehtab;Asadzadeh, Sahebali
    • Structural Engineering and Mechanics
    • /
    • 제50권6호
    • /
    • pp.797-816
    • /
    • 2014
  • Cooling tower is analyzed as an assembly of layered nonlinear shell elements. Geometric representation of the shell is enabled through layered nonlinear shell elements to define the different layers of reinforcements and concrete by considering the material nonlinearity of each layer for the cooling tower shell. Modal analysis using Ritz vector analysis and nonlinear time history analysis by direct integration method have been carried out to study the effects of the inclination of the supporting columns of the cooling tower shell on its dynamic characteristics. The cooling tower is supported by I-type columns and ${\Lambda}$-type columns supports having the different inclination angles. Relevant comparisons of the dynamic response of the structural system at the base level (at the junction of the column and shell), throat level and at the top of the tower have been made. Dynamic response of the cooling tower is found to be significantly sensitive to the change of the inclination of the supporting columns. It is also found that the stiffness of the structure system increases with increase in inclination angle of the supporting columns, resulting in decrease of the period of the structural system. The participation of the stiffness of the tower in structural response of the cooling tower is fund to be dependent of the change in the inclination angle and even in the types of the supporting columns.

알 카시의 첨두아치 작도와 티무르조 건축의 곡면구조 (Al-Kāshī's Pointed Arch Drawing and Curved Structure of the Timurid Architecture)

  • 최남섭
    • 건축역사연구
    • /
    • 제32권5호
    • /
    • pp.21-30
    • /
    • 2023
  • The study aims to analyze the geometric characteristics of the pointed arches proposed by Al-Kāshī in his book "Miftāḥ al-Ḥisāb" (Key of Arithmetic) and investigate their planning principles, architectural application, and typological characteristics. Al-Kāshī completed this significant work in 1427 and dedicated it to Ulugh Beg, a Timurid Sultan in Samarkand. In the ninth chapter, titled "Al-'Imārāt wa al-Abnīya" (Amīr's Mansion and Building), Al-Kāshī sought to measure the surface areas and volumes of barrel vaults (Azaj) and domes (Qubba). To achieve this, he proposed five kinds of pointed arches (Ṭāq) and analyzed their drawing methods and composition principles. The Īwān and Qubba structures, which are curved architectural elements, hold significant importance in Islamic architecture. However, previous research has predominantly focused on comparing the drawings in Al-Kāshī's book with historical buildings, neglecting the inherent characteristics of the drawings themselves. This study intends to contribute to a deeper understanding of Al-Kāshī's remarkable work and shed light on the geometric aspects of monumental structures in the Timurid Period.

Speaking of Religion

  • Pecora, Vincent P.
    • 인문언어
    • /
    • 제2권2호
    • /
    • pp.183-201
    • /
    • 2002
  • Since the end of the Cold War, debate about the grand struggle between capitalism and communism has been largely replaced by debate about religious sectarianism. Some have even referred to a "clash of civilizations" in the wake of the spread of Islamic fundamentalism. This is in fact an old debate, but it has been given new life by arguments about globalization and economic development as envisioned by the West, and especially by the terrorist attacks in New York on September 11, 2001. While the political right has had little difficulty treating religious belief as a fundamental human and social interest, much of the political left has remained committed to secular Enlightenment, even when it criticizes the hegemony of the West. The dispute depends upon competing notions of history, secularism, and progress, and ultimately on the possibility or desirability of universal solidarity. While for many a world unified by one religion may no longer make sense, the old Enlightenment dream that a single version of secular and universal reason will eventually prevail over religious difference may also need to be reconsidered. The process that we call secularization is neither as singular, nor as transparent, as we might think.

  • PDF

Influence of near-fault ground motions characteristics on elastic seismic response of asymmetric buildings

  • Tabatabaei, R.;Saffari, H.
    • Structural Engineering and Mechanics
    • /
    • 제40권4호
    • /
    • pp.489-500
    • /
    • 2011
  • The elastic seismic response of plan-asymmetric multi storey steel-frame buildings is investigated under earthquake loading with particular emphasis on forward-rupture directivity and fling records. Three asymmetric building systems are generated with different torsional stiffness and varying static eccentricity. The structural characteristic of these systems are designed according to UBC 97 code and their seismic responses subjected to a set of earthquake records are obtained from the response history analysis (RHA) as well as the linear static analysis (LSA). It is shown that, the elastic torsional response is influenced by the intensity of near-fault ground motions with different energy contents. In the extreme case of very strong earthquakes, the behaviour of torsionally stiff buildings and torsionally flexible buildings may differ substantially due to the fact that the displacement envelope of the deck depends on ground motion characteristics.

A new lateral load pattern for pushover analysis in structures

  • Pour, H. Gholi;Ansari, M.;Bayat, M.
    • Earthquakes and Structures
    • /
    • 제6권4호
    • /
    • pp.437-455
    • /
    • 2014
  • Some conventional lateral load patterns for pushover analysis, and proposing a new accurate pattern was investigated in present research. The new proposed load pattern has load distribution according weight and stiffness variation in height and mode shape of structure. The assessment of pushover application with mentioned pattern in X type braced steel frames and steel moment resisting frames, with stiffness and mass variation in height, was studied completely and the obtained results were compared with nonlinear dynamic analysis method (including time history analysis). The methods were compared from standpoints of some basic parameters such as displacement, drift and shape of lateral load pattern. It is concluded that proposed load pattern results are closer to nonlinear dynamic analysis (NDA) compared to other pushover load patterns especially in tall and medium-rise buildings having different stiffness and mass during the height.

Development of a Disperse Dye Immunoassay Technique for Detection of Antibodies against Neospora caninum in Cattle

  • Selahi, Fatemeh;Namavari, Mehdi;Hosseini, Mohammad Hossein;Mansourian, Maryam;Tahamtan, Yahya
    • Parasites, Hosts and Diseases
    • /
    • 제51권1호
    • /
    • pp.129-132
    • /
    • 2013
  • In this study a disperse dye immunoassay method was standardized and evaluated for detection of antibodies against Neospora caninum in cattle. Sera from 150 cattle with a recent history of abortion were collected and tested by commercial ELISA kit and a standardized in-house dye immunoassay system. The positivity rate for the sera used in this study was 34.6% for the disperse dye immunoassay (DDIA) compared to 32% obtained by ELISA kit. This study showed no significant difference between DDIA and ELISA. The results indicated that the DDIA provide an economic, simple, rapid and robust test for detection of N. caninum infection in cattle.

A study of the Xinfa Suanshu's catalogue (1628.0): Comparison with the star catalogue of the Tablae Rudolphinae

  • Jeon, Junhyeok;Lee, Yong-Bok
    • 천문학회보
    • /
    • 제43권2호
    • /
    • pp.49.1-49.1
    • /
    • 2018
  • The Xinfa Suanshu, which was an important astronomical book in East-Asia, was published in 1644. This book was including the star catalogue. We researched the data of 1365 stars recorded in this star catalogue (the equinox of the catalogue is identified to be 1628 year). According to our analysis, it can be presumed that the star catalogue's data were observed from at least two places or more. Based on historical background, we assumed that the Xinfa Sunashu's catalogue likely referenced knowledge from the Europe or Arab/Islamic culture. The researchers who have studied the Xinfa Sunashu's star catalogue have all focused on Brahe's star catalogue. But they did not provide clear evidence. Therefore, we are compared with the star data recorded in Tablae Rudolphinae. In conclusion, we confirmed that 881 stars among the 1365 stars were perfectly edited from position data of stars recorded in Brahe's star catalogue (1602).

  • PDF

근동지역의 복식연구 II -오스만 터어키(Osman Turkey)복식을 중심으로- (A Study on the Near East Costume (II) -Osman Turkey Costume-)

  • 오춘자;박길순
    • 복식문화연구
    • /
    • 제2권1호
    • /
    • pp.1-27
    • /
    • 1994
  • This result of the study on the costume of Osman Turkey are as following. 1. Empire of Osman Turkey(129∼1922) exerted an almost limites impact and influence on Europe and Asia during their regime 600 years. The distant ancestors of the Osman Turks were nomadic peoples, who wandered I tribal groups through the Central Asia. Therefore their costumes were based on nomadic culture. They had trade with West and East were influenced by Hellenism and Byzantium and grew, to a strong Islamic political power polygamy with which influence their clothing along with other culture. 2. Topkapi Saray was one of he principal residences of the Osman sultans and his court. Late 17 century, Topkapi Saray found many of kaftans of Osman Turks Empires of 14∼17 centuries. Otherwise we studied by the minatures of 16∼17 centuries, Since the Topkapi Saray became a museum in 1924, a program of careful restoration has made it possible to some pars of it to the public, after centuries neglection. 3. Osman Turkey Empire had important role in between West and East(silk-road). Economic, commercial, social and political factor of Turkey led to a development in the art of weaving (kema, kadife, catman, seraser, zerbeft, hatayi, kntnu, atlas)parallel to the rise and development of the Osman Turkey Empire itself, one which raised the art to a level attained nowwhere else in the world. Fabrics woven from gold and silver thread occupied a very important place in the court life of the time. This was due as much to their symbolic as to their material value, reflecting as they did the power, glory and magnificence of the Empire. 4. In order to study Eastern or Western history of costume one must study Turkey history of costume in advance. Also there is a great need of comparison to study of western, central and north eastern area history of costume.

  • PDF

Increased Risk of Childhood Acute Lymphoblastic Leukemia (ALL) by Prenatal and Postnatal Exposure to High Voltage Power Lines : A Case Control Study in Isfahan, Iran

  • Tabrizi, Maral Mazloomi;Bidgoli, Sepideh Arbabi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권6호
    • /
    • pp.2347-2350
    • /
    • 2015
  • Childhood acute lymphoblastic leukemia (ALL) is one of the most common hematologic malignancies, accounting for one fourth of all childhood cancer cases. Exposure to environmental factors around the time of conception or pregnancy can increase the risk of ALL in the offspring.This study aimed to evaluted the role of prenatal and postnatal exposure to high voltage power lines on the incidence of childhood ALL.This cross-sectional case control study was carried out on 22 cases and 100 controls who were born and lived in low socioeconomic families in Isfahan and hospitalized for therapeutic purposes in different hospitals from 2013-2014.With regard to the underlying risk factors, familial history and parental factors were noted but in this age, socioeonomic and zonal matched case control study, prenatal and childhood exposure to high voltage power lines was considered as the most important environmental risk factors of ALL (p=0.006, OR=3.651, CI 95%, 1.692-7.878). As the population was of low socioeconomic background, use of mobiles, computers and microwave was negligible. Moreover prenatal and postnatal exposure to indoor electrically charged objects was not determined to be a significant environmental factor. Thus, pre and post natal exposure to high voltage power lines and living in pollutant regions as well as familial influence could be described as risk factors of ALL for the first time in a low socioeconomic status Iranian population.