• Steel and Composite Structures
• /
• 제25권2호
• /
• pp.157-175
• /
• 2017

The novelty of this work is the use of a new displacement field that includes undetermined integral terms for analyzing thermal buckling response of functionally graded (FG) sandwich plates. The proposed kinematic uses only four variables, which is even less than the first shear deformation theory (FSDT) and the conventional higher shear deformation theories (HSDTs). The theory considers a trigonometric variation of transverse shear stress and verifies the traction free boundary conditions without employing the shear correction factors. Material properties of the sandwich plate faces are considered to be graded in the thickness direction according to a simple power-law variation in terms of the volume fractions of the constituents. The core layer is still homogeneous and made of an isotropic material. The thermal loads are assumed as uniform, linear and non-linear temperature rises within the thickness direction. An energy based variational principle is employed to derive the governing equations as an eigenvalue problem. The validation of the present work is checked by comparing the obtained results the available ones in the literature. The influences of aspect and thickness ratios, material index, loading type, and sandwich plate type on the critical buckling are all discussed.

• 한국연극학
• /
• 제49호
• /
• pp.49-71
• /
• 2013

Melodrama emerged as a form of the moral in the early modern age. As an approach 'the moral' not only means that rewarding virtue and punishing vice, but also refer to a principle of spiritual life and a way of life. -Melodrama theatricalizes a new vision of human life and society through a new type of the virtuous protagonist and sentiment/-ality. -This allows melodrama to be a dominant cultural form in this modern age, beyond the borders of the theater, mass-media, and literature. Virtue and sentiment/-ality are the core elements of melodrama, which differentiate it from tragedy and comedy especially in the structure and effect of the drama. Actually virtue and sentiment/-ality have been a main target of criticism. Virtue has been regarded as a trite quality of the stereotypical protagonist, and sentiment/-ality as a banal emotion which paralyzes an audience's recognition of reality. -However, this thesis regards both virtue and sentiment/-ality as vehicles for showing and sharing the morals of the modern age. First, the virtues of the protagonist included the general and universal ones of the bourgeois -at that times, the bourgeois represented themselves as a human being- such as the responsibility and obedience of a father, a mother, a wife, a husband, a daughter and a son. They also included the professional ethics such as courage, honesty, and justice and so on. The fall or salvation of the protagonist is largely determined by his/her private individual virtue. Second, sentiment/ality is a theatrical device that makes the audience internalize the protagonist's virtue. The protagonist expresses his/her universal virtue sentimentally, and the audience also expresses their virtue by sympathizing with the protagonist's virtue sentimentally. However, the melodramatic protagonist as an individual, is not connected with society, but remains isolated. As a result, s/he has no influence on the society, where s/he can only ends her/his play alone with a happy-ending. S/he is happy alone, or at best happy with his/her own family. On the contrary to this, tragic protagonist usually fixes social disorder through his/her fall. In that sense, we can say that melodrama presents only the half of the human life.

• Steel and Composite Structures
• /
• 제32권2호
• /
• pp.157-171
• /
• 2019

In this research, the dynamic instability region (DIR) of the sandwich nano-beams are investigated based on nonlocal strain gradient elasticity theory (NSGET) and various higher order shear deformation beam theories (HSDBTs). The sandwich piezoelectric nano-beam is including a homogenous core and face-sheets reinforced with functionally graded (FG) carbon nanotubes (CNTs). In present study, three patterns of CNTs are employed in order to reinforce the top and bottom face-sheets of the beam. In addition, different higher-order shear deformation beam theories such as trigonometric shear deformation beam theory (TSDBT), exponential shear deformation beam theory (ESDBT), hyperbolic shear deformation beam theory (HSDBT), and Aydogdu shear deformation beam theory (ASDBT) are considered to extract the governing equations for different boundary conditions. The beam is subjected to thermal and electrical loads while is resting on Visco-Pasternak foundation. Hamilton principle is used to derive the governing equations of motion based on various shear deformation theories. In order to analysis of the dynamic instability behaviors, the linear governing equations of motion are solved using differential quadrature method (DQM). After verification with validated reference, comprehensive numerical results are presented to investigate the influence of important parameters such as various shear deformation theories, nonlocal parameter, strain gradient parameter, the volume fraction of the CNTs, various distributions of the CNTs, different boundary conditions, dimensionless geometric parameters, Visco-Pasternak foundation parameters, applied voltage and temperature change on the dynamic instability characteristics of sandwich piezoelectric nano-beam.

• 정보보호학회논문지
• /
• 제12권4호
• /
• pp.77-85
• /
• 2002

본 논문에서는 TEA[7]와 TEA[6]의 축소된 라운드에 대한 불능 차분 공격 (Impossible Differential Cryptanalysis)에 관하여 알아본다. 이 두 블록 암호의 주요 설계원리는 단순성과 효율성의 추구이다. 그러나 단순성 추구가 큰 확산 (diffusion) 효과를 주지 못하여, XTEA와 TEA의 축소된 라운드에 대한 불능 차분 공격을 가능하게 한다. 구체적으로 말하면 12라운드 불능 차분 특성을 이용하여 14라운드 XTEA에 대하여 $2^{62.5}$개의 선택평문들과 $2^{85}$번의 암호화 과정을 통하여 128비트 마스터키를 찾아낼 수 있다. 또한, TEA의 경우 10라운드 불능 차분 특성을 이용하여 11라운드 마스터키를 $2^{52.5}$개의 선택평문들과 약 $2^{84}$번의 암호화 과정을 통하여 찾아낸다.

• 대한안전경영과학회지
• /
• 제24권1호
• /
• pp.61-72
• /
• 2022

This study aims to propose a conceptual design of information displays for supporting responsive actions under severe accidents in Nuclear Power Plants (NPPs). Severe accidents in NPPs can be defined as accident conditions that are more severe than a design basis accident and involving significant core degradation. Since the Fukushima accident in 2011, the management of severe accidents is increasing important in nuclear industry. Dealing with severe accidents involves several cognitively complex activities, such as situation assessment; accordingly, it is significant to provide human operators with appropriate knowledge support in their cognitive activities. Currently, severe accident management guidelines (SAMG) have been developed for this purpose. However, it is also inevitable to develop information displays for supporting the management of severe accidents, with which human operators can monitor, control, and diagnose the states of NPPs under severe accident situations. It has been reported that Ecological Interface Design (EID) framework can be a viable approach for developing information displays used in complex socio-technical systems such as NPPs. Considering the design principles underlying the EID, we can say that EID-based information displays can be useful for dealing with severe accidents effectively. This study developed a conceptual design of information displays to be used in severe accidents, following the stipulated design process and principles of the EID framework. We particularly attempted to develop a conceptual design to make visible the principle knowledge to be used for coping with dynamically changing situations of NPPs under severe accidents.

• 기독교교육논총
• /
• 제71권
• /
• pp.371-399
• /
• 2022

우리가 살아가고 있는 시대는 각 분야와 영역의 경계와 한계가 사라지고 서로 유기적으로 융합되고 공유되는 초연결성의 시대이다. 초연결성의 시대를 살아가는 그리스도인들은 거룩과 세속, 교회와 세상, 영혼과 육체, 신앙과 삶, 인간과 자연 등 다양한 구분과 단절로 삶의 방향을 잃어가고 있다. 그러나 초연결성 사회에서는 단절로 인한 분열과 갈등에서 벗어나 인간과 자연과 세상이 서로 연결되고 연대함을 통해 하나님나라를 구현해야 한다. 이를 위한 기독교교육의 방향성을 모색하기 위해 본 연구는 초연결성 시대의 특성과 초연결성의 핵심인 연대성의 원리를 살펴보았다. 연대성의 신학적 의미는 인간과 자연과 세상의 측면에서 살펴보았고, 이러한 이해를 바탕으로 초연결성 시대의 기독교교육의 방향을 모색한바 첫째, 시대와 세대의 흐름을 인식하되 절대적 가치를 따를 것 둘째, 페리코레시스적 존재양식을 가진 호모커넥투스의 신앙적 인간이해를 할 것 셋째, 연대적 관계성 속에서 함께 더불어 살아갈 수 있는 정의와 평화의 하나님 나라에 대한 교육을 할 것 등으로 요약할 수 있다.

• Structural Engineering and Mechanics
• /
• 제85권3호
• /
• pp.289-304
• /
• 2023

The main objective of this paper is to study the effect of porosity on the buckling behavior of thick functionally graded sandwich plate resting on various boundary conditions under different in-plane loads. The formulation is made for a newly developed sandwich plate using a functional gradient material based on a modified power law function of symmetric and asymmetric configuration. Four different porosity distribution are considered and varied in accordance with material propriety variation in the thickness direction of the face sheets of sandwich plate, metal foam also is considered in this study on the second model of sandwich which containing metal foam core and FGM face sheets. New quasi-3D high shear deformation theory is used here for this investigate; the present kinematic model introduces only six variables with stretching effect by adopting a new indeterminate integral variable in the displacement field. The stability equations are obtained by Hamilton's principle then solved by generalized solution. The effect of Pasternak and Winkler elastic foundations also including here. the present model validated with those found in the open literature, then the impact of different parameters: porosities index, foam cells distribution, boundary conditions, elastic foundation, power law index, ratio aspect, side-to-thickness ratio and different in-plane axial loads on the variation of the buckling behavior are demonstrated.

• 대순사상과 동아시아종교
• /
• 제2권1호
• /
• pp.111-132
• /
• 2022

In the 1920s, a new religion emerged in Tay Ninh Province, Southern Vietnam, under the name Caodaism; also known as the Third Universal Salvation of the Great Dao. It is the result of the typical combination of three main religions (Buddhism, Daoism, and Confucianism). Different ethnic groups populated Tay Ninh, such as Chinese, Khmer, Cham, and Kinh. Additionally, the core principle of Caodaism is known as The Three Religions Returned to the Origin, and it is also expanded as The Five Branches Reunited. The Five Branches are humankind's five ways of self-cultivation: the Way of Humans, the Way of Deities, the Way of Saints, the Way of Immortals, and the Way of Buddhas. Although Caodaism was only founded in 1920, this religion is well known domestically and internationally. This is because Caodaism has a distinctive identity; it is a new religion that advocates a syncretistic combination of essential religious teachings that follow the harmonization and reconciliation between the East and West as well as between the past and present. Moreover, the Tay Ninh Holy See is the most important, first, and largest Cao Dai temple in Vietnam. The temple is located in Tay Ninh Province in southwestern Vietnam. This article aims to introduce the Tay Ninh Holy See as the birthplace of Caodaism and as the largest Cao Dai religious palace, not only in Vietnam but also in other countries that practice Caodaism. A brief overview of Tay Ninh Holy See's origin, history, and planning will be provided. Most importantly, the style of the architecture at the Tay Ninh Holy See will be comprehensively analyzed to shed more light on the meaning of each section and the details of this temple structure.

• 사물인터넷융복합논문지
• /
• 제9권2호
• /
• pp.55-60
• /
• 2023

최근 클라우드 컴퓨팅의 수요가 증가하고 자택근무 및 외부 업무로 인한 원격접속의 증가했다. 또한 외부 공격자의 접근뿐만이 아니라 내부 직원의 업무 접속과 같은 내부에서의 접근을 경계해야 할 필요성이 증가함과 동시에 다양한 공격 기법들이 고도화되는 현 상황에서 그에 맞는 새로운 보안 패러다임이 요구된다. 이로 인해 모든 것을 의심하고 신뢰하지 않는다는 핵심 원칙을 가진 제로 트러스트(Zero-Trust)를 적용한 네트워크 보안 모델이 보안업계에서 주목받기 시작했다. 제로 트러스트 보안은 모든 네트워크를 감시하고 접근을 허용 받기 위해선 먼저 인증을 받아야 하며 접근 요청자에 대한 최소한의 접근 권한을 부여함으로써 보안성을 높인다. 본 논문에서는 제로 트러스트와 제로 트러스트 아키텍처에 대해 설명하고, 제로 트러스트와 블록체인을 이용하여 기존 보안 시스템의 한계점을 극복하고 다양한 기업에서 활용할 수 있고 접근제어 강화를 위한 새로운 클라우드 보안 체계를 제안하고자 한다.

• 스마트미디어저널
• /
• 제12권5호
• /
• pp.46-57
• /
• 2023

코로나 팬데믹과 IT 기술의 발전으로 원격 및 재택 근무가 점차 보편화되며, 클라우드 컴퓨팅 기술이 발전하고 있으며, 사이버 공격 기법 또한 더욱 세련되고 고도화되고 있다. 이러한 추세에 따라 기업에서는 기존의 경계 기반 보안을 벗어나 제로트러스트를 적용하여 보안을 강화하려는 움직임이 점차 커지고 있다. 제로트러스트는 모든 것을 의심하고 신뢰하지 않는다는 핵심 원리를 바탕으로 모든 트래픽을 식별하고 엄격한 인증과정을 통해 접근 권한을 부여함으로써 보안을 강화한다. 본 논문에서는 제로트러스트의 도입 배경과 선진적으로 도입을 추진하고 있는 국가들의 도입 정책과 동향에 대해서 분석하고, 기업 보안을 강화하기 위해 국가나 기관에서 필요한 노력과 더불어. 기업에서 제로트러스트를 적용할 때 유의해야 할 내용도 함께 제안한다.