• Structural Engineering and Mechanics
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• 제86권1호
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• pp.85-92
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• 2023

This article examines the seismic vulnerability of soil nail wall structures. Detailed information regarding finite element modeling has been provided. The fragility function evaluates the relationship between ground motion intensities and the probability of surpassing a specific level of damage. The use of incremental dynamic analysis (IDA) has been applied to the soil nail wall against low to severe ground motions. In the nonlinear dynamic analysis of the soil nail wall, a set of twenty seismic ground motions with varying PGA ranges are used. The numerical results demonstrate that the soil-nailed wall reaction is extremely sensitive to earthquake ground vibrations under different intensity measures (IM). In addition, the analytical fragility curve is provided for various intensity values.

• 한국수학교육학회:학술대회논문집
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• 한국수학교육학회 2010년도 제44회 전국수학교육연구대회
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• pp.261-267
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• 2010

Both history of mathematics and education of mathematics is old subject. The question arises wether can these two important subjects can help each other or not. Unfortunately this idea made mathematics society into two groups; one has idea that history of mathematics can help education of mathematics and other group has idea that not only history of mathematics can not help education of mathematics but also it makes some confusion. In this article the author is going to do some comparison and take some conclusion that history of mathematics can make education of mathematics so active and interesting.

• 시큐리티연구
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• 제50호
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• pp.175-206
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• 2017

이 연구는 인도네시아 이슬람 극단주의 역사와 최근의 인도네시아의 국제 이슬람 극단주의의 확산 실태를 조사한다. 이 연구의 수행을 위해서는 인도네시아 이슬람 극단주의 관련 문헌조사와 관련자들의 질적 인터뷰를 병행한다. 문헌조사를 위해서는 미디어 보도, 관련 연구 보고서와 논문 등을 수집하고 활용한다. 질적 인터뷰를 위해서는 국내체류 인도네시아 학생들과 체류자들, 인도네시아인과 결혼한 한국인 배우자들, 인도네시아 현지에서 활동하는 한국인 선교사들 등을 포함한다. 이들에 대한 질적 인터뷰는 30분에서 2시간에 걸쳐 진행되었다. 연구대상의 모집단을 사실상 특정화 할 수 없으며 연구주제의 성격상 인터뷰 대상에 접근이 용이하지 않았기 때문에 편의 샘플과 눈덩이 샘플 추출 방식을 활용하였다. 연구결과에 따르면, 인도네시아의 이슬람 극단주의는 뿌리가 깊고 일반적으로 아프가니스탄, 파키스탄, 이집트, 사우디아라비아 등과 같이 이슬람 극단주의가 공고히 뿌리를 내리고 있는 다른 무슬림 국가들과 유사한 역사적 경험을 공유한다. 즉, 서방 제국주의에 대한 반작용으로 이슬람 원리주의가 시작되었으며, 독립이후 근대국가 발전과정에서 소외되었고 소련-아프간 전쟁을 거치며 극단화 폭력화 하는 과정을 거쳤다. 또한 9.11테러 이후 국제적 이슬람 극단주의 네트워크와 연결되어 글로벌 지하드에 편입되는 발전경로를 보여준다. 이러한 역사적 발전 궤적은 인도네시아의 이슬람 극단주의가 상당히 조직적이고 공고하다는 것을 알려준다. 한편, 최근 들어 IS와 알카에다 등의 국제 이슬람 극단주의 세력의 동아시아 확장전략에 따라 인도네시아로의 침투와 확장이 관찰된다. 이는 특히 인도네시아의 소외되고 낙후한 시골지역에서 보다 뚜렷이 관찰된다. 이러한 인도네시아에서의 국제 이슬람 극단주의 세력의 확산은 지리적 근접성, 국내 상당규모의 이주자 공동체의 존재 등의 사실을 고려할 때 직접적으로 우리 국가에 위협을 미치게 될 것이다. 이러한 맥락에서 인도네시아 내에서의 이슬람 극단주의 확산 동향에 대한 주의와 관심은 시기적으로 매우 필요하다고 볼 수 있다.

• Earthquakes and Structures
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• 제13권2호
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• pp.103-118
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• 2017

In vertical seismic isolation (VSI), a building is partitioned intentionally by vertical layers into two dynamically different substructures for seismic response reduction. Initially, a 1-story frame was partitioned into two substructures, interconnected by viscous and visco-elastic links, and seismic responses of the original and the vertically isolated structures (VIS) were obtained, considering a large number of stiffness and mass ratios of substructures with respect to the original structure. Color contour graphs were defined for presentation and investigation of large amounts of output results. Dynamic characteristics of the isolated structures were studied by considering the non-classical damping of the system, and then the effects of viscous and visco-elastic link parameters on the modal damping ratios were discussed. On this basis, three states of mass isolation, interactional state, and control mass were differentiated. Response history analyses were performed by Runge-Kutta numerical method. In these analyses, interaction of isolation ratios and link parameters, on response control of VIS was studied and the appropriate ranges for link parameters as well as the optimal ranges for isolation ratios were suggested. Results show that by using the VSI technique, seismic response reduction up to 50% in flexible substructure and even more in stiff substructure is achievable.

• Structural Engineering and Mechanics
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• 제88권3호
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• pp.263-271
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• 2023

Base isolation is a widely used technique for the seismic control of structures as it reduces the structural seismic demand. However, displacement of the isolation layer is not economically feasible in congested urban areas. To resolve the issue, an innovative system is proposed here to isolate both horizontally at the base and vertically in the upper portion of the structure. A simplified linear three degree-of-freedom (3DOF) model of the system that considers the mass and stiffness ratios of the substructure has been introduced and analyzed in MATLAB by spectrum analysis. The 3DOF model results revealed that, when the period of the soft substructure reaches 2.5 times that of the stiff substructure, the isolation and the lower substructure responses decrease by 65% and 51%, respectively. Time-history analysis of a MDOF system at three frequency ratios under a wide range of ground motions indicated that, at the expense of accepting a certain large drift by the soft substructure in the upper portion of the structure, base isolation displacement can be decreased by 10%.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제28권4호
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• pp.493-511
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• 2014

우리는 본 논문에서 초등학교 수학 교과서가 다루는 주요 수학사를 알아보았다. 우리나라 초등수학 교과서는 기축시대가 반영된 수학사를 다루고 있으며, 또한, 고대 이집트, 고 바빌로니아, 그리고 이슬람 수학을 배제하고 고대 그리스에서 로마, 유럽으로 수학문화의 전이를 왜곡하여 다루고 있다. 이를 초등수학 교과서를 통하여 알아보고 그 보완방안을 제시하였다.

• Earthquakes and Structures
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• 제5권4호
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• pp.417-438
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• 2013

This study was concerned on the application of a hybrid approach for analyzing the buried pipelines deformations subjected to earthquakes. Nonlinear time-history analysis of Finite Element (FE) model of buried pipelines, which was modeled using laboratory data, has been performed via selected earthquakes. In order to verify the FE model with experiments, a statistical test was done which demonstrated a good conformity. Then, the FE model was developed and the optimum intersection angle of pipeline and fault was obtained via genetic algorithm. Transient seismic strain of buried pipeline in the optimum intersection angle of pipeline and fault was investigated considering the pipes diameter, the distance of pipes from fault, the soil friction angles and seismic response duration of buried pipelines. Also, a two-layer perceptron Artificial Neural Network (ANN) was trained using results of FE model, and a nonlinear relationship was obtained to predict the bending strain of buried pipelines based on the pipes diameter, intersection angles of the pipelines and fault, the soil friction angles, distance of pipes from the fault, and seismic response duration; whereas it contains a wide range of initial input data without any requirement to laboratory measurements.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4411-4416
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• 2014

Breast cancer is the most common cancer in females all over the world with approximately one million new cases each year as well as one of second leading causes of death among females. In Pakistan, the most frequently diagnosed cancer among females is also breast cancer, accounting for nearly one in nine female patients. Its incidence in Pakistan is 2.5 times higher than that in neighboring countries like Iran and India. The risk factors associated with breast cancer are age, family history, early menarche, intake of combined estrogen and progestin menopausal hormones, alcohol consumption, physical inactivity, low socioeconomic status and lack of awareness regarding the disease. This mini-review article aims to provide awareness about breast cancer as well as an updated knowledge about the prevalence, risk factors and disease knowledge of breast cancer in Pakistan.

• Earthquakes and Structures
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• 제15권4호
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• pp.431-441
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• 2018

This study provides fragility-based assessment of seismic performance of reinforced concrete bridges. Seismic fragility curves were created using nonlinear analysis (NA) and artificial neural networks (ANNs). Nonlinear response history analyses were performed, in order to calculate the seismic performances of the bridges. To this end, 306 bridge-earthquake cases were considered. A multi-layered perceptron (MLP) neural network was implemented to predict the seismic performances of the selected bridges. The MLP neural networks considered herein consist of an input layer with four input vectors; two hidden layers and an output vector. In order to train ANNs, 70% of the numerical results were selected, and the remained 30% were employed for testing the reliability and validation of ANNs. Several structures of MLP neural networks were examined in order to obtain suitable neural networks. After achieving the most proper structure of neural network, it was used for generating new data. A total number of 600 new bridge-earthquake cases were generated based on neural simulation. Finally, probabilistic seismic safety analyses were conducted. Herein, fragility curves were developed using numerical results, neural predictions and the combination of numerical and neural data. Results of this study revealed that ANNs are suitable tools for predicting seismic performances of RC bridges. It was also shown that yield stresses of the reinforcements is one of the important sources of uncertainty in fragility analysis of RC bridges.

• 복식문화연구
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• 제11권6호
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• pp.941-955
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• 2003

In this study, the researcher investigated how tailored garment were accepted and developed in India where the traditional costumes, such as Sari and Dhothi, excluding the tailored process, were mainly worn. It is suspected that pants and coats were first introduced during the Kushan Dynasty but they scarcely influenced on the costumes of India. In the 7th Century when Islam made its entrance in India, pants and coats were not accepted in India due to the exclusive attitudes of Indians, Hindu. Pants and coats were worn locally as Indian costumes through the Islamic Mughul Empire in the 16th Century. During that period, the cultural exchange between Islam and Hindu made the change of the clothes of India reflected the mixing of Islamic and Hindu elements. The colonization of India by Great Britain that was the turning point for diverse kinds of tailored garment in the costume history of India inasmuch as western elements were introduced. The western style tailored method and design changed the appearance of Indian pants into slimmer style. The style spread and influenced on the design of indian clothes greatly; hence, western style shirts and coats were accepted in India.