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An Efficient Anchor Range Extracting Algorithm for The Unit Structuring of News Data (뉴스 정보의 단위 구조화를 위한 효율적인 앵커구간 추출 알고리즘)

  • 전승철;박성한
    • Journal of Broadcast Engineering
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    • v.6 no.3
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    • pp.260-269
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    • 2001
  • This paper proposes an efficient algorithm extracting anchor ranges that exist in news video for the unit structuring of news. To this purpose, this paper uses anchors face in the frame rather than the cuts where the scene changes are occurred. In anchor range, we find the end position (frame) of anchor range with the FRFD(Face Region Frame Difference). On the other hand, in not-anchor range, we find the start position of anchor range by extracting anchors face. The process of extracting anchors face is consists of two parts to enhance the computation time for WPEG decoding. The first pact is to find candidates of anchors face through rough analysis with partial decoding MPEG and the second part is to verify candidates of anchors face with fully decoding. It is possible to use the result of this process in basic step of news analysis. Especially, the fast processing and the high recall rate of this process are suitable to apply for the real news service.

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Mitigation of progressive collapse in steel structures using a new passive connection

  • Mirtaheri, Masoud;Emami, Fereshteh;Zoghi, Mohammad A.;Salkhordeh, Mojtaba
    • Structural Engineering and Mechanics
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    • v.70 no.4
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    • pp.381-394
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    • 2019
  • If an alternative path would not be considered for redistribution of loads, local failure in structures will be followed by a progressive collapse. When a vertical load-bearing element of a steel structure fails, the beams connected to it will lose their support. Accordingly, an increase in span's length adds to the internal forces in beams. The mentioned increasing load in beams leads to amplifying the moments there, and likewise in their corresponding connections. Since it is not possible to reinforce all the elements of the structure against this phenomenon, it seems rational to use other technics like specified strengthened connections. In this study, a novel connection is suggested to handle the stated phenomenon which is introduced as a passive connection. This connection enables the structure to tolerate the added loads after failing of the vertical element. To that end, two experimental models were constructed and thereafter tested in half-scale, one-story, double-bay, and bolted connections in three-dimensional spaces. This experimental study has been conducted to compare the ductility and strength of a frame that has ordinary rigid connections with a frame containing a novel passive connection. At last, parametric studies have been implemented to optimize the dimensions of the passive connection. Results show that the load-bearing capacity of the frame increased up to 75 percent. Also, a significant decrease in the displacement of the node wherein the column is removed was observed compared to the ordinary moment resisting frame with the same loads.

The Conversion of Narrative Strategy: from "An Outpost of Progress" to Heart of Darkness (서술 전략의 전환-「진보의 전초기지」에서 『어둠의 핵심』으로)

  • Lee, Man Sik
    • Journal of English Language & Literature
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    • v.57 no.4
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    • pp.625-649
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    • 2011
  • Even though "An Outpost of Progress" and Heart of Darkness were based upon Joseph Conrad the sailor's same experience in Congo Free State, their narrative strategies are quite different. The realistic representation of "An Outpost of Progress," with which Conrad was not satisfied at all, was converted into the modernistic narrative strategy of Heart of Darkness so that the sympathetic power of the story should be improved. The conservative value system of realism is expressed by the omniscient author in "An Outpost of Progress," whereas the frame narrator of Heart of Darkness is proved to be an unreliable one whose norms and behavior are not in accordance with the implied author. The glorious history of the British Empire, which was proudly presented by the frame narrator at the beginning of Heart of Darkness, was strongly opposed by Marlow, another narrator, who said that the British Empire had been "one of the dark places of the earth" when ruled by the Roman Empire. The feeling of the frame narrator was uneasily changed into the gloomy mood when he described the Thames as the flow which "seemed to lead into the heart of an immense darkness" at the end of Heart of Darkness. Similar to the straightforward narrative strategy of representation in "An Outpost of Progress," the realistic approach of Part I in Heart of Darkness is considered by Conrad as insufficient to reveal the darkest truth of imperialism, which was declared by Kurtz as "The Horror! The Horror!" Thus Conrad uses the Chinese-box structure, in which Kurtz' episode is enveloped by Marlow's tale which is enclosed by the frame narrator's story, in order to penetrate into the mind of ordinary readers in the novelist's age of New Colonialism, while attacking the ideology itself of imperialism instead of critisizing its inefficiency and individualism.

Evaluation of Emulative Level for Precast Moment Frame Systems with Dry Mechanical Splices by Using Nonlinear Dynamic Analysis (비선형동적해석을 통한 건식 기계적이음을 갖는 프리캐스트 모멘트 골조의 동등성 평가)

  • Kim, Seon-Hoon;Lee, Won Jun;Lee, Deuckhang
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.2
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    • pp.85-92
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    • 2024
  • This study presents code-compliant seismic details by addressing dry mechanical splices for precast concrete (PC) beam-column connections in the ACI 318-19 code. To this end, critical observations of previous test results on precast beam-column connection specimens with the proposed seismic detail are briefly reported in this study, along with a typical reinforced concrete (RC) monolithic connection. On this basis, nonlinear dynamic models were developed to verify seismic responses of the PC emulative moment-resisting frame systems. As the current design code allows only the emulative design approach, this study aims at identifying the seismic performances of PC moment frame systems depending on their emulative levels, for which two extreme cases were intentionally chosen as the non-emulative (unbonded self-centering with marginal energy dissipation) and fully-emulative connection details. Their corresponding hysteresis models were set by using commercial finite element analysis software. According to the current seismic design provisions, a typical five-story building was designed as a target PC building. Subsequently, nonlinear dynamic time history analyses were performed with seven ground motions to investigate the impact of emulation level or hysteresis models (i.e., energy dissipation performance) on system responses between the emulative and non-emulative PC moment frames. The analytical results showed that both the base shear and story drift ratio were substantially reduced in the emulative system compared to that of the non-emulative one, and it indicates the importance of the code-compliant (i.e., emulative) connection details on the seismic performance of the precast building.

Seismic Tests of Steel Beam-to-column Moment Connections with Inclined End-plate Beam Splice (경사단부강판 보 이음을 갖는 강재 보-기둥 모멘트접합부의 내진실험)

  • Lim, Jong Jin;Kim, Dong Gwan;Lee, Sang Hyun;Park, Choul Soo;Lee, Chang Nam;Eom, Tae Sung
    • Journal of Korean Society of Steel Construction
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    • v.29 no.2
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    • pp.181-192
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    • 2017
  • A beam splice method using inclined end-plates and high-strength tension bolts was developed. The end-plates welded to a bracket and a spliced beam are connected each other by using the tension bolts. In the present study, six exterior beam-to-column moment connections were tested under cyclic loading. Test parameters were the end-plate details and bolt arrangements. All specimens were designed so that moment resistances of the end-plates and bolts were greater than the required moment at the beam splice, in accordance with the design methods of AISC Design Guide 4. Test results showed that in the beam splices with the extended end-plates, the beam moment successfully transferred to the bracket, without any defeats such as excessive prying action of the end plates and brittle failure at the end plate-to-beam flange weld joints. However, the deformation capacities of the overall beam-to-column connections were limited due to the brittle failure of the beam-to-column flange weld joints. From the test results, recommendations for seismic design and detailing of the beam-to-column moment connection with inclined end-plate beam splice were given.

Behavior Analysis of RMPM Applied Steel Frame Structures (반력모멘트를 이용한 라멘형 철골구조물의 거동분석)

  • Ahn, Jin Hee;Kim, Jun Hwan;Kim, Tae Yeon;Kim, Sang Hyo;Lee, Sang Woo
    • Journal of Korean Society of Steel Construction
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    • v.19 no.6
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    • pp.611-620
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    • 2007
  • The beam-column connection is the critical design section of general steel frame structures owing to the behavioral characteristics of the structural system. As most members of a frame structure are composed of rolled section beams, the cross-section of the beam members is governed by the negative bending moment near beam-column connections. Such a design concept leaves a redundant load-carrying capacity at the positive bending regions of the beam members leading to design inefficiency. Therefore, it is of utmost importance to redistribute the beam end moments and reduce the stresses at the beam-column connections for a more efficient design of steel frame structures. In this study, reaction-moment prestressing method (RMPM) was proposed for the innovative design and construction of steel frame structures. The RMPM is a prestressing method utilizing the elastic bending deformation of a beam member induced by temporary prestressing for the distribution of a relatively large bending moment to other sections for the efficient use of the beam section. By the application of the RMPM, the negative bending moment at the beam-column connections can be significantly reduced, ultimately leading to possible use of smaller beam sections. Through a series of model tests and numerical analyses of steel frame structures, the moment distributing effect and feasibility of the RMPM was verified.

Experimental investigation of force-distribution in high-strength bolts in extended end-plate connections

  • Abdalla, K.M.;Abu-Farsakh, G.A.R.;Barakat, S.A.
    • Steel and Composite Structures
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    • v.7 no.2
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    • pp.87-103
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    • 2007
  • This paper presents some of the results from an experimental research project on the behavior of extended end-plate connections subjected to moment conducted at the Structural Laboratory of Jordan University of Science and Technology. Since the connection behavior affects the structural frame response, it must be included in the global analysis and design. In this study, the behavior of six full-scale stiffened and unstiffened cantilever connections of HEA- and IPE-sections has been investigated. Eight high strength bolts were used to connect the extended end-plate to the column flange in each case. Strain gauges were installed inside each of the top six bolts in order to obtain experimentally the actual tension force induced within each bolt. Then the connection behavior is characterized by the tension force in the bolt, extended end-plate behavior, moment-rotation relation, and beam and column strains. Some or all of these characteristics are used by many Standards; therefore, it is essential to predict the global behavior of column-beam connections by their geometrical and mechanical properties. The experimental test results are compared with two theoretical (equal distribution and linear distribution) approaches in order to assess the capabilities and accuracy of the theoretical models. A simple model of the joint is established and the essential parameters to predict its strength and deformational behavior are determined. The equal distribution method reasonably determined the tension forces in the upper two bolts while the linear distribution method underestimated them. The deformation behavior of the tested connections was characterized by separation of the column-flange from the extended end-plate almost down to the level of the upper two bolts of the lower group and below this level the two parts remained in full contact. The neutral axis of the deformed joint is reasonably assumed to pass very close to the line joining the upper two bolts of the lower group. Smooth monotonic moment-rotation relations for the all tested frames were observed.

Experimental seismic behaviour of L-CFST column to H-beam connections

  • Zhang, Wang;Chen, Zhihua;Xiong, Qingqing;Zhou, Ting;Rong, Xian;Du, Yansheng
    • Steel and Composite Structures
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    • v.26 no.6
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    • pp.793-808
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    • 2018
  • In this study, the seismic performance of the connections between L-shaped columns composed of concrete-filled steel tubes (L-CFST columns) and H-beams used in high-rise steel frame structures was investigated. Seven full-scale specimens were tested under quasi-static cyclic loading. The variables studied in the tests included the joint type, the axial compression ratio, the presence of concrete, the width-to-thickness ratio and the internal extension length of the side plates. The hysteretic response, strength degradation, stiffness degradation, ductility, plastic rotation capacity, energy dissipation capacity and the strain distribution were evaluated at different load cycles. The test results indicated that both the corner and exterior joint specimens failed due to local buckling and crack within the beam flange adjacent to the end of the side plates. However, the failure modes of the interior joint specimens primarily included local buckling and crack at the end plates and curved corners of the beam flange. A design method was proposed for the flexural capacity of the end plate connection in the interior joint. Good agreement was observed between the theoretical and test results of both the yield and ultimate flexural capacity of the end plate connection.

Molecular Cloning of Mutant cDNA of PU.1 Gene (PU.1 유전자(cDNA)의 인위적 변이체 클로닝)

  • 류종석;유시현
    • KSBB Journal
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    • v.10 no.5
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    • pp.499-509
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    • 1995
  • PU.1, a tissue-specific transcription activator, binds to a purine-rich sequence(5'-GAGGAA-3') called PU box. The PU.1 cDNA consists of an open reading frame of 816 nucleotides coding for 272 amino acids. The amino terminal end is highly acidic, while the carboxyl terminal end is highly basic. Transcriptional activation domain is located at the amino terminal end, while DNA binding domain is located at the carboxyl terminal end. Activation of PU.1 transcription factor is supposed to be accomplished by the phosphorylation of serine residue(s). There exist 22 serines in the PU.1. Five(the 41, 45, 132$.$133, and 148th) of the serines(plausible phosphorylation site by casein kinase II), are the primary targets of interest in elucidating the molecular mechanism(s) of the action of the PU.1 gene. In this study, PU.1 cDNA coding for the five serine residues(41th AGC, 45th AGC, 132$.$133th AGC$.$TCA, and 148th TCT), was mutated to alanine codon(41th GCC, 45th GCC, 132$.$133th GCC$.$GCA, and 1481h GCT), respectively, by Splicing-Overlapping-Extension(SOE) using Polymerase Chain Reaction(PCR). And each mutated cDNA fragments was ligated into pBluescript KS+ digested with HindIII and Xba I, to generate mutant clones named pKKS41A, pRKS45A, pMKS132$.$133A, and pMKS148A. The clones will be informative to study the "Structure and Function" of the immu-nologically important gene, PU.1.

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A Material Characteristic Study on the Sword with an Undecorated Ring Pommel of the Ancient Tombs of Jeongchon, Bogam-Ri, Naju (나주 복암리 정촌고분 출토 소환두도의 재료학적 특성)

  • Lee, Hyeyoun
    • Korean Journal of Heritage: History & Science
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    • v.52 no.3
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    • pp.160-171
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    • 2019
  • The sword with a ring pommel, which was excavated from the first stone chamber of the ancient tombs of Jeongchon Village in Naju, is a sword with a pentagon undecorated ring pommel consisting of a mother sword and two child swords. The sword with an undecorated ring pommel of Jeongchon comprises a ring pommel, a hilt, a knife, and a knife end decoration. This sword was coated with lacquer. The ring pommel is an iron frame covered with silver plate; however the silver tarnished into a light purple due to silver chloride corrosion, and iron corrosion originated from the inside is visible on the surface. Silver chloride corrosion is produced when silver objects are exposed to water, dissolved salts, and dissolved chloride ions when in a buried state. It changes objects into powder, making it difficult to preserve original shapes. The other silver artifacts found in the Jeongchon ancient tombs show similar signs of corrosion. The results of X-ray irradiation and a CT analysis showed that the sword had a ring at the end of the handle, a T-shaped hilt, and was probably connected to the handle end of a knife. If the shape of the mother sword can be inferred from the child swords, the mother sword had a ring pommel, decorations of the handle, covered with silver plate, and a gold ring and a silver line wound around the handle. It is assumed that the ring pommel was connected to the knife by welding because no holes were observed. The end decoration of the knife was made by using an iron plate formed into a shape, half covered by silk, and the other half decorated with silver plate and a gold ring. The sword with an undecorated ring pommel excavated from the ancient tombs of Jeongchon Village comprises the metals of gold, silver, and iron, and includes features of Baekje, Silla, and Gaya, which highlights the influence of surrounding historic sites and various cultures.