• Title/Summary/Keyword: post-2012

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The Development of School Uniform Design for the Post-digital Generation (포스트디지털 세대의 교복 디자인 개발)

  • Mun, Jihyun;Na, Hyunshin
    • Fashion & Textile Research Journal
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    • v.14 no.5
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    • pp.758-765
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    • 2012
  • As the 21st century is the post-digital era, a mix of the hard digital and the soft analog realm, the school uniform designs for the post-digital generation need to be changed within this paradigm shift. Thus, this study is conducted with the purpose of developing the school uniform design that reflects aesthetic value and sensitivity of the post-digital generation. The definition and background of the post-digital generation is reviewed and the values of this generation are drawn based on the theoretical research. Also, through the survey of 205 high school girls in Seoul, the purchase, wear & fit, and suggestions for improvement of present school uniforms are investigated. Based on the studies above, the guidelines for designing school uniforms for the post-digital generation are established and the products are developed.

Post-buckling analysis of Timoshenko beams made of functionally graded material under thermal loading

  • Kocaturk, Turgut;Akbas, Seref Doguscan
    • Structural Engineering and Mechanics
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    • v.41 no.6
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    • pp.775-789
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    • 2012
  • This paper focuses on post-buckling analysis of functionally graded Timoshenko beam subjected to thermal loading by using the total Lagrangian Timoshenko beam element approximation. Material properties of the beam change in the thickness direction according to a power-law function. The beam is clamped at both ends. The considered highly non-linear problem is solved by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. As far as the authors know, there is no study on the post-buckling analysis of functionally graded Timoshenko beams under thermal loading considering full geometric non-linearity investigated by using finite element method. The convergence studies are made and the obtained results are compared with the published results. In the study, with the effects of material gradient property and thermal load, the relationships between deflections, end constraint forces, thermal buckling configuration and stress distributions through the thickness of the beams are illustrated in detail in post-buckling case.

Post-buckling analysis of Timoshenko beams with temperature-dependent physical properties under uniform thermal loading

  • Akbas, Seref Doguscan;Kocaturk, Turgut
    • Structural Engineering and Mechanics
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    • v.44 no.1
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    • pp.109-125
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    • 2012
  • Post-buckling behavior of Timoshenko beams subjected to uniform temperature rising with temperature dependent physical properties are studied in this paper by using the total Lagrangian Timoshenko beam element approximation. The beam is clamped at both ends. In the case of beams with immovable ends, temperature rise causes compressible forces end therefore buckling and post-buckling phenomena occurs. It is known that post-buckling problems are geometrically nonlinear problems. Also, the material properties (Young's modulus, coefficient of thermal expansion, yield stress) are temperature dependent: That is the coefficients of the governing equations are not constant in this study. This situation suggests the physical nonlinearity of the problem. Hence, the considered problem is both geometrically and physically nonlinear. The considered highly non-linear problem is solved considering full geometric non-linearity by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. The beams considered in numerical examples are made of Austenitic Stainless Steel (316). The convergence studies are made. In this study, the difference between temperature dependent and independent physical properties are investigated in detail in post-buckling case. The relationships between deflections, thermal post-buckling configuration, critical buckling temperature, maximum stresses of the beams and temperature rising are illustrated in detail in post-buckling case.

Dynamic Characteristic of Post-tensioned Void Slab (포스트텐션 중공슬래브의 동적 특성)

  • Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.12 no.3
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    • pp.89-95
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    • 2012
  • Post-tensioned void slab is frequently used for improving the deflection and sound proofing. Two one story 8m spanned structures were built. One structure applied post-tensioned solid slab, but the other did post-tensioned void slab. Dynamic characteristics, which is natural frequency and damping ratio, was compared between that of solid slab and void slab before and after post tension. The natural frequency of void slab was greater than that of solid slab before and after post tension. It was shown that damping ratio of solid slab and void slab was almost same at two stages.

ISO14971:2019 detailed analysis and Post Market Surveillance Application Method - Focusing on IVDR requirements (ISO14971:2019 세부분석과 Post Market Surveillance의 적용 방안 - IVDR 요구사항 중심으로)

  • Knag, Il Kyu
    • Journal of Biomedical Engineering Research
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    • v.43 no.4
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    • pp.199-213
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    • 2022
  • EN ISO 14971:2012 a risk management standard approved and applied as a European standard in 2012, will be adopted and applied as ISO 14971:2019 published in December 2019, ISO/TR 24971(Guidance) published in June 2020 from May 2022. After that, it is applied to IVDD surveillance and IVDR new and conversion, and the manufacturer is already preparing for application or is starting preparation for application. In addition, 98/78/EEC IVDD applied from 1998 will also be applied as REGULATION (EU) 2017/746 IVDR from May 2022. In particular, in IVDR, the requirements for post-marketing investigations such as Post Market Surveillance (PMS), Summary of safety and performance(SSP), Periodic Safety Update Report(PSUR) and Post Market Performance Follow Up(PMPF), which were not required in the existing IVDD, increased, and the contents were also specified. This study focused on ISO14971:2019 among these strengthened and newly applied regulations, and tried to present a detailed analysis and application plan of Post Market Surveillance (PMS) required by 2017/746 IVDR.

Analysis of Defense Method for HTTP POST DDoS Attack base on Content-Length Control (Content-Length 통제기반 HTTP POST DDoS 공격 대응 방법 분석)

  • Lee, Dae-Seob;Won, Dong-Ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.4
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    • pp.809-817
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    • 2012
  • One of the OSI 7 Layer DDoS Attack, HTTP POST DDoS can deny legitimate service by web server resource depletion. This Attack can be executed with less network traffic and legitimate TCP connections. Therefore, It is difficult to distinguish DDoS traffic from legitimate users. In this paper, I propose an anomaly HTTP POST traffic detection algorithm and http each page Content-Length field size limit with defense method for HTTP POST DDoS attack. Proposed method showed the result of detection and countermeasure without false negative and positive to use the r-u-dead-yet of HTTP POST DDoS attack tool and the self-developed attack tool.

A Case Study of the Discrepancy between Ex Ante and Ex Post Evaluation of IS Performance (정보화 성과의 사전-사후평가 차이에 관한 사례연구)

  • Lee, Kuk-Hie;Park, So-Hyun;Gu, Bon-Jae;Lee, Mi-Young
    • Journal of Information Technology Applications and Management
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    • v.19 no.2
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    • pp.59-78
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    • 2012
  • The purpose of this longitudinal case study is to shed light on the reliability problems of IS performance evaluation by analyzing the discrepancy between ex ante evaluation in 2011 and ex post evaluation in 2012. Through an information system development project of a public enterprise, the gap between ex ante and ex post evaluation was ascertained and the causes as to why such gap occurs and the success factors that can solve the problems were derived. The ex ante evaluation of IS performance was performed based on both IS success model and BSC model and the ex post evaluation was carried out at the time after the target system has been built up by applying the evaluation measures and process that are similar to the ex ante evaluation. In the ex ante evaluation the business performance improved by the target system was estimated to 18.2%. On the other hand, it was seen as being low at 15.2% in the ex post evaluation and the differences were found to be statistically significant in 6 out of 10 measures. The reasons as to why such gap occurs were diagnosed as being of 2 types : (1) changes in the evaluation psychology according to the differences in the evaluation objectives; and (2) excessive expectation levels of the target system that is formed at the time of the ex ante evaluation. In other words, the users who have excessive expectations tend to overestimate in the ex ante evaluation and, in the ex post evaluation, tend to underestimate lower than the actual performance mainly due to disappointment on the results that do not meet the early expectations. As solutions to overcome the reliability problem of ex ante evaluation, 3 factors were derived : (1) the temperance of excessive expectation levels of the users; (2) a clear definition of the scope and functionality of the target system; and (3) actual commitments for the evaluations of IT performance.

Assessment of Recanalization after Intra-Arterial Thrombolysis in Patients with Acute Ischemic Stroke : Proposed Modification of the Qureshi Grading System

  • Kim, Jae-Hoon;Kang, Hee-In;Moon, Byung-Gwan;Lee, Seung-Jin;Kim, Joo-Seung
    • Journal of Korean Neurosurgical Society
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    • v.51 no.5
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    • pp.262-267
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    • 2012
  • Objective : We aimed to investigate the correlation between the success of recanalization and a modified version of the Qureshi grading system in acute ischemic stroke patients. Methods : We retrospectively analyzed the intra-arterial thrombolysis (IAT) records of 37 patients who were evaluated by Thrombolysis in Myocardial Infarction (TIMI) and a modified version of the Qureshi grading systems as follows : 1) post-IAT Qureshi grade, 2) modified ${\Delta}$ Qureshi grade : pre-IAT group grade - post-IAT group grade (grade 1 : Qureshi grades 0-2 and grade 2 : Qureshi grade 3-5) and 3) ${\Delta}$ Qureshi grade (post-IAT Qureshi grade - pre-IAT Qureshi grade). Successful recanalization was defined as follows : 1) post-IAT TIMI grades 2 and 3, 2) post-IAT Qureshi grade 0-2, 3) modified ${\Delta}$ Qureshi grade=1, and 4) ${\Delta}$ Qureshi grade of ${\geq}2$ and/or post-IAT Qureshi grade=0. We investigated the correlation between the post-IAT TIMI grade and the modified Qureshi grade and also compared the various grading systems with modified Rankin Scale scores for evaluating the clinical outcome at 3 months. Results : The post-IAT Qureshi grade and ${\Delta}$ Qureshi grade and/or post-IAT Qureshi grade were significantly correlated with the TIMI grade (${\gamma}$=0.976 and, 0.942, respectively). Further, post-IAT Qureshi grade and ${\Delta}$ Qureshi grade and/or post-IAT Qureshi grade showed a significantly stronger association with clinical outcome than did the post-IAT TIMI grade (p=0.001 and, 0.000 vs. 0.083, respectively). Conclusion : Our preliminary results suggest that the modified Qureshi grading system is a useful tool for assessing the success of recanalization after IAT.

The study about the reduction of HC in diesel PCCI combustion by double post injections (이단 후분사의 적용을 통한 디젤 PCCI 연소의 HC 저감에 관한 연구)

  • Park, Youngsoo;Bae, Choongsik
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.179-182
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    • 2012
  • Effect of double post injections on diesel PCCI combustion with focus on HC emission was investigated in a single-cylinder direct-injection diesel engine. The ISFC, HC and CO emissions were reduced by single or double post injections. The application of double post injections could also improve the trade-off relationship between NOx and HC emissions under wide EGR rate range.

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