• Structural Engineering and Mechanics
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• 제27권4호
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• pp.393-408
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• 2007

This paper presents the findings of an experimental study to evaluate retrofit methods which address particular weaknesses that are often found in reinforced concrete structures, especially older structures, namely the lack of the required flexural and shear reinforcement within the columns and the lack of the required shear reinforcement within the joints. Thus, the use of a high-strength fiber jacket for cases of post-earthquake and pre-earthquake retrofitting of columns and beam-column joints was investigated experimentally. In this paper, the effectiveness of the two jacket styles was also compared.

• 한국언어정보학회지:언어와정보
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• 제10권2호
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• pp.67-94
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• 2006

This paper revisits some old issues of irony, i.e., situational vs. verbal irony, and irony vs. paradox, in order to further clarify the issues. Although these issues seem to have been fully discussed, there are still unresolved and/or vague aspects that need to be accounted for. This paper also revisits the issue of theorizing the phenomenon of verbal irony, which has long been scrutinized by many philosophers and linguists including Aristotle, Grice, Sperber and Wilson, and recently, Utsumi and Attardo.

• Earthquakes and Structures
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• 제12권1호
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• pp.1-12
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• 2017

Historical earthquakes have shown that successive seismic events may occur in regions of high seismicity. Such a sequence of earthquakes has the potential to increase the damage level of the structures, since any rehabilitation between the successive ground motions is practically impossible due to lack of time. Few studies about this issue can be found in literature, most of which focused their attention on the seismic response of SDOF systems or planar frame structures. The aim of the present study is to examine the impact of seismic sequences on the damage level of 3D multistorey R/C buildings with various structural systems. For the purposes of the above investigation a comprehensive assessment is conducted using three double-symmetric and three asymmetric in plan medium-rise R/C buildings, which are designed on the basis of the current seismic codes. The buildings are analyzed by nonlinear time response analysis using 80 bidirectional seismic sequences. In order to account for the variable orientation of the seismic motion, the two horizontal accelerograms of each earthquake record are applied along horizontal orthogonal axes forming 12 different angles with the structural axes. The assessment of the results revealed that successive ground motions can lead to significant increase of the structural damage compared to the damage caused by the corresponding single seismic events. Furthermore, the incident angle can radically alter the successive earthquake phenomenon depending on the special characteristics of the structure, the number of the sequential earthquakes, as well as the distance of the record from the fault.

• Molecules and Cells
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• 제24권2호
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• pp.224-231
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• 2007

$H_2O_2$, as an example of oxidative stress, induces cardiac myocyte apoptosis. Bcl-2 family proteins are key regulators of the apoptotic response while their functions can be regulated by post-translational modifications including phosphorylation, dimerization or proteolytic cleavage. In this study, we examined the role of various protein kinases in regulating total BAD protein levels in adult rat cardiac myocytes undergoing apoptosis. Stimulation with 0.1 mM $H_2O_2$, which induces apoptosis, resulted in a marked down-regulation of BAD protein, which is attributed to cleavage by caspases since it can be restored in the presence of a general caspase inhibitor. Inhibition of PKC, p38-MAPK, ERK1/2 and PI-3-K did not influence the reduced BAD protein levels observed after stimulation with $H_2O_2$. On the contrary, inhibition of PKA or specifically $PKC{\delta}$ resulted in up-regulation of BAD. Decreased caspase 3 activity was observed in $H_2O_2$ treated cells after inhibition of PKA or $PKC{\delta}$ whereas inhibition of PKA also resulted in improved cell survival. Furthermore, addition of okadaic acid to inhibit selected phosphatases resulted in enhanced BAD cleavage. These data suggest that, during oxidative stress-induced cardiac myocyte apoptosis, there is a caspase-dependent down-regulation of BAD protein, which seems to be regulated by coordinated action of PKA, $PKC{\delta}$ and phosphatases.

• Steel and Composite Structures
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• 제13권6호
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• pp.571-586
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• 2012

The paper addresses some key issues related to the design of composite slabs with cold-formed profiled steel sheets. An experimental programme is first presented, involving six composite slab specimens tested with a view to evaluating Eurocode 4 (EC4) provisions on testing of composite slabs. In four specimens, the EC4-prescribed 5000 load cycles were applied using different load ranges resulting from alternative interpretations of the reference load $W_t$. Although the rationale of the application of cyclic loading is to induce loss of chemical bond between the concrete plate and the steel sheet, no such loss was noted in the tests for either interpretation of the range of load cycles. Using the recorded response of the specimens the values of factors m and k (related to interface shear transfer in the composite slab) were determined for the specific steel sheet used in the tests, on the basis of three alternative interpretations of the related EC4 provisions. The test results confirmed the need for a more unambiguous description of the m-k test and its interpretation in a future edition of the Code, as well as for an increase in the load amplitude range to be used in the cyclic loading tests, to make sure that the intended loss of bond between the concrete slab and the steel sheet is actually reached. The study also included the development of a special-purpose software that facilitates design of composite slabs; a parametric investigation of the importance of m-k values in slab design is presented in the last part of the paper.

• Earthquakes and Structures
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• 제17권3호
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• pp.297-306
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• 2019

The extension of existing RC buildings is a challenging process, which requires efficient connection between existing and new materials to guarantee load transferring between the lap-spliced longitudinal columns' reinforcement. Therefore, the length of the columns' starter bars is a crucial factor, which decisively affects the seismic response of the new columns. In particular, when the length of the starter bars is short, then the length of the lap splices of reinforcement is inadequate to ensure load transfer between steel bars and concrete, with an indisputable detrimental impact on the seismic behaviour of the columns. Moreover, in most of the existing RC buildings the column starter bars are of particularly short length, while they have probably been bent, cut or corroded. In the present study, the effectiveness of both welded rebar and mechanical splices of reinforcement in ensuring load transferring between the starter bars and the longitudinal reinforcement of the new column was experimentally evaluated. Four cantilever column subassemblages were constructed and subjected to earthquake-type loading. Three of the specimens were used to examine different types of shielded metal arc welding (SMAW), while in the fourth subassemblage mechanical splices were tested. The hysteretic response of the columns was evaluated and compared to the behaviour of a fifth specimen with continuous reinforcement, tested by Kalogeropoulos and Tsonos (2019). Test results clearly demonstrated that the examined types of SMAW were equally satisfactory in ensuring the ductile seismic performance of the columns, while the mechanical splices found to be more susceptible to exhibit slipping of the bars.

• 비교문화연구
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• 제50권
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• pp.371-394
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• 2018

황금세기 스페인 연극의 대표적 걸작으로 평가되는 "세비야의 별"은 17세기의 대표적인 극작가인 로뻬의 비극작품이다. 그러나 이 연극은 뛰어난 작품성에도 불구하고 로뻬의 창작 진위 여부를 둘러싼 여러 논란들로 인해 스페인에서도 작품 자체에 대한 본격적인 연구는 그리 많이 이루어지지 않았다. 이에 본 연구에서는 이 연극이 가지고 있는 비극성을 크게 아리스토텔레스적 관점과 셰익스피어적 관점으로 나누어 구체적으로 살펴보고자 한다. 이 연극은 주인공들의 고귀한 사회적 신분이나 남자주인공 산초 오르띠스의 고뇌하는 적절한 대사 등 덕분에 아리스토텔레스가 말하는 카타르시스적 기능을 수행하는 데에는 별 문제가 없어 보인다. 그러나 아리스토텔레스적 비극의 핵심적 본질인 '절대적 운명에 저항하는 주인공의 자유의지'의 측면에서는 다소 문제점이 발견된다. 이 연극에는 절대적 운명을 형성하는 핵심적 장치인 하마르티아가 부재하고, 이에 따라 절대적 운명이나 운명의 불가항력성이 설정되어있지 않기 때문이다. 오히려 이 연극이 지닌 비극성은 셰익스피어적 관점에서 좀 더 온전하게 규명되어질 수 있다. 아리스토텔레스와 달리 셰익스피어는 비극성을 주인공의 성격으로부터 비롯된 것이라고 여긴다. 즉 절대적 운명과 같은 외부적 요인이 아닌 주인공 자신의 가치관과 성격으로부터 비극이 시작된다는 것이다. 실제로 이 연극의 두 가지 비극적 사건인 부스또의 죽음과 산초 오르띠스와 에스뜨레야의 이별은 불가항력적인 사건이라기보다 전횡을 휘두른 국왕 산초 4세의 비뚤어진 이기심과 욕망, 그리고 산초 오르띠스의 국왕에 대한 지나치게 맹목적인 충성심으로 인해 비롯된 것이라 할 수 있다. 즉, 절대적 권력의 부당함 앞에 궁극적으로 할 수 있는게 아무것도 없다는 무기력한 상황 그리고 이로 인한 절망감이야말로 이 연극의 비극적 결말을 목격하며 관객들이 느꼈을 비극적 감정인 것이다.

• Structural Engineering and Mechanics
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• 제52권2호
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• pp.391-403
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• 2014

In this study an innovative method of earthquake-resistant strengthening of reinforced concrete structures is presented for the first time. Strengthening according to this new method consists of the construction of steel fiber high-strength concrete jackets without conventional reinforcement which is usually applied in the construction of conventional reinforced concrete jackets (i.e., longitudinal reinforcement, stirrups, hoops). The proposed in this study innovative steel fiber high-strength or ultra high-strength concrete jackets were proved to be much more effective than the reinforced concrete jackets and the FRP-jackets when used for the earthquake-resistant strengthening of reinforced concrete structural members.

• Structural Engineering and Mechanics
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• 제14권5호
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• pp.543-563
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• 2002

The use of the epoxy pressure injection technique to rehabilitate reinforced concrete beam-column joints damaged by strong earthquakes is investigated experimentally and analytically. Two one-half-scale exterior beam-column joint specimens were exposed to reverse cyclic loading similar to that generated from strong earthquake ground motion, resulting in damage. Both specimens were typical of new structures and incorporated full seismic details in current building codes. Thus the first specimen was designed according to Eurocode 2 and Eurocode 8 and the second specimen was designed according to ACI-318 (1995) and ACI-ASCE Committee 352 (1985). The specimens were then repaired with an epoxy pressure injection technique. The repaired specimens were subjected to the same displacement history as that imposed on the original specimens. The results indicate that the epoxy pressure injection technique was effective in restoring the strength, stiffness and energy dissipation capacity of specimens representing a modem design.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 1989년도 한글날기념 학술대회 발표논문집
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• pp.65-72
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• 1989

이 논문은 국어 부정문의 의미분석을 위하여 바람직한 의미이론을 제안하려는 것이 목적이다. 특히, 이 논문에서는, 국어의 내부부정 (internal negation)은 물론 외부부정 (external negation)에 상응하는 문장부정의 통사구조가 있다는 것을 논의를 통하여 입증한다. 그러고, 이러한 부정문의 의미를 표상하기 위하여, 부정문 대한 기존의 이론을 수정, 보완할 것을 구체적으로 제안한다. 특히, 아리스토텔레스 (Aristotle)의 부정논리에 입각한 전통에 일치하는 몬테그 (Montague)의 부정문 규칙이 국어의 부정문 처리에는 만족스럽지 못한 점을 지적한다. 그러고, 이러한 문제를 해결하기 위하여 수정된 규칙을 제안한다. 이어서 최근에 발전된 상황의미론(situation semantics) 에서 국어의 문장부정을 다루는데 야기될 수 있는 문제를 지적하고, 이러한 문제를 처리 할 수 있는 이론적 대안을 마련한다. 특히 국어의 외부부정이 야기시키는 중의성의 문제를 잘 다룰 수 있는 바람직한 의미론을 세운다. 그리고 나아가서는 부정문에 대한 보편적 통사-의미론의 기틀을 마련하려는 것이다.