• Title/Summary/Keyword: Second-frame

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Study on Estimate of Thermal Resistance of PVC Frame Window Due to Material Composition (PVC 창호의 구성에 따른 단열성능 예측에 관한 연구)

  • Sung, Uk-Joo;Lee, Jin-Sung;Cho, Soo;Jang, Cheol-Yong;Paek, Sang-Hun;Song, Kyoo-Dong
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.1075-1080
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    • 2006
  • Purpose of this study is proposal of estimating method about window thermal performance that based on KS F 2278 'Test method of thermal resistance for windows and doors' due to material composition of PVC frame window. First step of this study is research of present state about material composition of PVC frame window. Second is selection of main effective elements about window thermal resistance. For example, composition of Glazing, Frame area ratio of total window area, frame width, opening type, area of heat transfer and so on. Third is multiple regression analysis about thermal performance of PVC frame window due to main effective elements. It produces equations of multiple regression analysis due to opening type. Case of sliding window is $Y=0.149+0.034X_g+0.248X_{far}$, 4track sliding is $Y=0.584+0.175X_g+1.355X_{far}-0.008X_{fw}$, Tilt & Turn window is $Y=-0.161+0.076X_g+0.576X_{far}+0.0008X_{fw}$.

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Finite element modeling of pre-damaged beam in concrete frame retrofitted with ultra high performance shotcrete

  • Xuan-Bach Luu
    • Computers and Concrete
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    • v.33 no.2
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    • pp.121-136
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    • 2024
  • In recent times, there has been a growing need to retrofit and strengthen reinforced concrete (RC) structures that have been damaged. Numerous studies have explored various methods for strengthening RC beams. However, there is a significant dearth of research investigating the utilization of ultra-high-performance concrete (UHPC) for retrofitting damaged RC beams within a concrete frame. This study aims to develop a finite element (FE) model capable of accurately simulating the nonlinear behavior of RC beams and subsequently implementing it in an RC concrete frame. The RC frame is subjected to loading until failure at two distinct degrees, followed by retrofitting and strengthening using Ultra high performance shotcrete (UHPS) through two different methods. The results indicate the successful simulation of the load-displacement curve and crack patterns by the FE model, aligning well with experimental observations. Novel techniques for reinforcing deteriorated concrete frame structures through ABAQUS are introduced. The second strengthening method notably improves both the load-carrying capacity and initial stiffness of the load-displacement curve. By incorporating embedded rebars in the frame's columns, the beam's load-carrying capacity is enhanced by up to 31% compared to cases without embedding. These findings indicate the potential for improving the design of strengthening methods for damaged RC beams and utilizing the FE model to predict the strengthening capacity of UHPS for damaged concrete structures.

A Note on Complex Two-Phase Sampling with Different Sampling Units of Each Phase

  • Lee, Sang Eun;Jin, Young;Shin, Key-Il
    • Communications for Statistical Applications and Methods
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    • v.22 no.5
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    • pp.435-443
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    • 2015
  • Two phase sampling design is useful to increase estimation efficiency using deep stratification, improved non-response adjustment and reduced coverage bias. The same sampling units are commonly used for the first and the second phases in complex two-phase sampling design. In this paper we consider a sampling scheme where the first phase sampling units are clusters and the second phase sampling units are list samples. Using selected clusters in first phase requires that we list up elements in the selected clusters from the first phase and then use the list as a secondary sampling frame for the second phase sampling design. Then we select second phase samples from the listed sampling frame. We suggest an estimator based on the complex two-phase sampling design with different sampling units of each phase. Also the estimated variances of the estimator obtained by using classic and replication variance methods are considered and compared using simulation studies. For real data analysis, 2010 Korea Farm Household Economy Survey (KFHES) and 2011 Korea Agriculture Survey (KAS) are used.

A Comparative Analysis of Broadcasting News about Social Conflict Issues: Focused on Between Central and Local News Frame (사회갈등 이슈에 대한 방송뉴스보도 비교 연구: 중앙과 지역의 보도 프레임 비교를 중심으로)

  • Nam, Chong-Hoon
    • Journal of Digital Contents Society
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    • v.12 no.4
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    • pp.475-483
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    • 2011
  • This study examines how television news constructed an issue of social conflict between nationwide and local broadcasting. Especially, this study focused on new ariport of east-south region in Korea. To do this, this study conducted frame analysis on KBS, MBC, SBS main news including national and local ones, broadcasted from 1 January, 2011 to 15 April, 2011. In addition, frame analysis was divided into two aspects, formal and substance. As a result, the findings are as follow: First, in formal aspect both national and local broadcastings are dealing with episode style news frames, while subject style is just 7.5%. Second, in substance aspect, 6 categories are founded: site decision frame, competition and conflict frame, economic frame, rescission and response frame, government countermeasure and alternative frame, etc frame. In conclusion, national and local broadcasting television news have different perspective each other on defining an issues of social conflict like east-south new airport.

Evaluation of seismic response of soft-storey infilled frames

  • Santhi, M. Helen;Knight, G.M. Samuel;Muthumani, K.
    • Computers and Concrete
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    • v.2 no.6
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    • pp.423-437
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    • 2005
  • In this study two single-bay, three-storey space frames, one with brick masonry infill in the second and third floors representing a soft-storey frame and the other without infill were designed and their 1:3 scale models were constructed according to non-seismic detailing and the similitude law. The models were excited with an intensity of earthquake motion as specified in the form of response spectrum in Indian seismic code IS 1893-2002 using a shake table. The seismic responses of the soft-storey frame such as fundamental frequency, mode shape, base shear and stiffness were compared with that of the bare frame. It was observed that the presence of open ground floor in the soft-storey infilled frame reduced the natural frequency by 30%. The shear demand in the soft-storey frame was found to be more than two and a half times greater than that in the bare frame. From the mode shape it was found that, the bare frame vibrated in the flexure mode whereas the soft-storey frame vibrated in the shear mode. The frames were tested to failure and the damaged soft-storey frame was retrofitted with concrete jacketing and, subjected to same earthquake motions as the original frames. Pushover analysis was carried out using the software package SAP 2000 to validate the test results. The performance point was obtained for all the frames under study, therefore the frames were found to be adequate for gravity loads and moderate earthquakes. It was concluded that the global nonlinear seismic response of reinforced concrete frames with masonry infill can be adequately simulated using static nonlinear pushover analysis.

A Study on Degradation Characteristic of High Strength Fire Resistance Steel for Frame Structure by Acoustic Emission (음향방출법에 의한 고강도 구조요 내화강의 열화특성에 관한 연구)

  • 김현수;남기우;강창룡
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.04a
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    • pp.51-56
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    • 2000
  • Demand for new nondestructive evaluations is growing to detect tensile crack growth behavior to predict long term performance of materials and structure in aggressive environments, especially when they are in non-visible area. Acoustic emission technique is well suited to these problems and has drawn a keen interests because of its dynamic detection ability, extreme sensitivity and location of growing defects. In this study, we analysed acoustic emission signals obtained in tensile test of high strength fire resistance steel for frame structure with time frequency analysis methods. The results obtained are summaries as follows ; In the T and TN specimen consisting of ferrite and pearlite grains, most of acoustic emission events were produced near yield point, mainly due to the dislocation activities during the deformation. However, B specimen under $600^{\circ}C$ - 10min had a two peak which was attribute to the presence of martensite phase. The first peak is before yield point the second is after yield point. The sources of second acoustic emission peak were the debonding of martensite-martensite interface and the micro-cracking of brittle martensite phase. In $600^{\circ}C$-30min to $700^{\circ}C$-60min specimens, many signals were observed from area before yield point and counts were decreased after yield point.

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The empirical corner stiffness for right-angle frames of rectangular and H-type cross-sections

  • Kwon, Young-Doo;Kwon, Soon-Bum;Gil, Hyuck-Moon;Cho, Hui-Jeong
    • Structural Engineering and Mechanics
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    • v.51 no.3
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    • pp.471-485
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    • 2014
  • Until now, the finite corner stiffness of the right-angle frames used as horizontal girders in a bonnet, have not been considered during the design process to result in not a precise result. This paper presents a design equation set for right-angle frames used as horizontal girders in a bonnet assuming rigid corner stiffness. By comparing the center stresses of the right-angle frame according to the design equation set with the results of the finite element method, the master curves for the empirical corner stiffness can be determined as a function of slenderness ratio. A second design equation set for a right-angle frame assuming finite corner stiffness was derived and compared with the first equation set. The master curves for the corner stiffness and the second design equation set can be used to determine the design moments at the centers of the girder so that the bending stresses can be analyzed more precisely.

A Gyro-Free INS Algorithm in the Navigation Frame and Its Application to the Spinning Vehicle with High Rotation Rate

  • Lee, Junhak;Kim, Heyone;Oh, Sang Heon;Do, Jae Chul;Nam, Chang Woo;Hwang, Dong-Hwan;Lee, Sang Jeong
    • Journal of Positioning, Navigation, and Timing
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    • v.7 no.2
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    • pp.91-103
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    • 2018
  • Conventional inertial measurement units cannot be used in the spinning vehicle with high rotation rate due to gyro's narrow operation range. By the way, angular acceleration can be measured using the accelerometer array distributed in the vehicle. This paper derives a mechanization for the gyro-free INS in the navigation frame, and proposes a gyro-free INS algorithm based on the derived mechanization. In addition, the proposed algorithm is used to estimate angular velocity, attitude, velocity, and position of a spinning vehicle with high rotation rate. A MATLAB-based software platform is configured in order to show validation of the proposed algorithm. The reference trajectory of a spinning vehicle at 3 round per second, 30 round per second are set up, and the outputs of accelerometer are generated when triads of accelerometer are located at the origin and all the axes. Navigation results of the proposed algorithm for the generated output are presented. The results show that the proposed navigation algorithm can be applied to the spinning vehicle with high rotation rate.

Influence of DIC Frame Rate on Experimental Determination of Instability and Fracture Points for DP980 Sheets under Various Loading Conditions (다양한 하중 조건에서 DP980 판재의 불안정성 및 파단점 결정시 DIC Frame Rate의 영향)

  • Noh, E.;Hong, S.
    • Transactions of Materials Processing
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    • v.28 no.6
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    • pp.368-374
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    • 2019
  • The past recent years have seen an increasing use of high-strength steel sheets in the automotive industry. However, the formability and damage prediction of these materials requires accurate acquisition of necking and fracture strains. Digital image correlation (DIC) is used to accurately capture the necking and fracture strains during testing. The fact that single time points of capturing vary with frame rate makes the need for an investigation necessary. For the high-strength steel DP980, the frame-rate dependences of the final necking and fracture strains values are analyzed here. To eliminate the influence of gauge length, the strains were measured locally by DIC. Results for three specimen shapes obtained with frame rates of 1 and 900 fps (frames per second) were considered and based on them, triaxiality failure diagrams (TFD) are established. It was observed that after diffuse necking, the deformation path departed from the initially linear one, and the stress triaxiality grew with ongoing deformation. It was further revealed that the frame rate-dependence of the necking strain was rather low (< 2%), whereas the fracture strain could be underestimated by up to 8% when the lower frame rate of 1 fps was used (compared with 900 fps). In this study, this issue is investigated while taking into consideration the three different triaxialities. These results demonstrate the importance of choosing an appropriate frame rate for the determination of necking and fracture strains in particular.

The Classification of Fashion Frame and Fashion Image of Korean Women in their Twenties and Thirties (한국 20~30대 여성의 패션 프레임과 패션이미지 유형화)

  • Shin, Sae-Young;Kim, Young-In
    • Journal of the Korean Society of Costume
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    • v.63 no.4
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    • pp.118-131
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    • 2013
  • The purpose of this study is to take a look at the fashion frame of Korean women in their twenties and thirties to sort the actual fashion image and the ideal fashion image according to the fashion frame of Korean women in their twenties and thirties, and also to find out the standards and features that divide such a classification. For this study, we used the Q method, which is valued as an effective way to assess subjectivity. This helps to objectively classify the perception the fashion images of and the response to them as well. The analyzed materials were divided into two actual fashion frames and two ideal fashion frames, and classified them into 12 fashion image types in total, that is, six actual fashion images and six ideal fashion images, and we named each type of the fashion images and analyzed the features of each fashion image type through the in-depth Q workshop in which 14 professionals participated. The results of this study are as follows: First, the actual fashion frames of Korean women in their twenties and thirties was largely divided into 'Fashion Gold Girl', the fashion frame of mainstream and 'Indi-idol', the fashion frame of subcultures, and this was further divided into six fashion image types: 'Basic Casual', 'Vintage Performer', 'Easy Chic', 'Ladies' Look', 'City Office Girl' and 'Club Mania'. Second, the ideal fashion frame of Korean women in their twenties and thirties was divided into 'Urban Refinement', the fashion frame of the mainstream and 'Mismatched Style', the fashion frame of subcultures. It was also divided into six fashion image types: Power Fashion', 'Fashion Conservative', 'Semi-culture', 'Fashion Otaku', 'Sweet Darling' and 'Fashion Panic'. Third, The characteristics of the fashion images' colors are recognizable according to the type of fashion images.