• 제목/요약/키워드: Second Impact

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사회영향평가의 원칙 및 지침에 관한 연구 - 미국 사례를 중심으로 - (Principles and Guidelines for Social Impact Assessment: A Critical Review on the US Case)

  • 정주철;임재영
    • 환경영향평가
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    • 제16권1호
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    • pp.45-58
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    • 2007
  • Despite the ubiquitous practice of environmental impact assessment around the world, social impact assessment has been alienated from assessment process from the beginning. Not until 1993 was 'Interorganizational Committee' established in the United States to prepare for 'Principles and Guidelines for Social Impact Assessment.' This study is an attempt to critically examine US 'Principles and Guidelines.' First, the study traces history of social impact assessment to reveal why the latter became "the orphan in the assessment process." Second, it critically reviews 'Principles and Guidelines' to find its merits and defects. For instance, a principle regarding environmental justice is perceived as necessary as society has become conscious of social justice and equity while putting too much emphasis on predictive traits of social impact assessments only fosters "checklist mentality." Third, the study reflects on 'Principles and Guidelines' in particular and social impact assessment in general in order to probe what is social impact assessment. To do so, it pays attention to scholars, who have criticized technocratic and procedural elements of 'Principles and Guidelines.' They show that social impact assessment is philosophically and methodologically teleological in that "fluid and contested meanings" between social impacts and the public are meaningful in itself. And simple procedural guarantee of the public involvement, they argue, is not enough to define social impacts. Lastly, from the critical analysis of 'Principles and Guideline,' the study looks for alternatives to improve how to assess social impacts in a Korean context.

Analysis of colliding index on impact behavior of RC columns under repeated impact loading

  • Tantrapongsaton, Warakorn;Hansapinyo, Chayanon;Wongmatar, Piyapong;Limkatanyu, Suchart;Zhang, Hexin;Charatpangoon, Bhuddarak
    • Computers and Concrete
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    • 제30권1호
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    • pp.19-32
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    • 2022
  • This paper presents an investigation into the failure of RC columns under impact loadings. A numerical simulation of 19 identical RC columns subjected to single and repeated impact loadings was performed. A free-falling hammer was dropped at midspan with the same total kinetic energy input but varying mass and momentum. The specimens under the repeated impact test were struck two times at the same location. The colliding index, defined as the impact energy-momentum ratio, was proposed to explain the different impact responses under equal-energy impacts. The increase of colliding index from low to high indicates the transition of the impact response from static to dynamic and failure mode from flexure to shear. This phenomenon was more evident when the column had a greater axial load and was impacted with a high colliding index. The existence of the axial load had an inhibitory effect on the crack development and increased the shear resistance. The second impact changes the failure mode from flexural to brittle shear as found in the specimen with 20% axial load subjected to high a colliding index. Moreover, a deflection prediction equation based on the impact energy and force was limited to the low colliding index impact.

세포 병리 자문 재판독의 진단 불일치에 관한 연구: 서울아산병원의 경험 (Second Opinion Diagnoses of Cytologic Specimens on Consultation : Asan Medical Center Experience)

  • 박소형;노재윤;조경자;공경엽;조영미;강신광
    • 대한세포병리학회지
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    • 제19권2호
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    • pp.99-106
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    • 2008
  • Background : Second opinion diagnosis of outside pathology slides is a common practice for efficient and proper patient management. We analyzed cytology slides from outside hospitals submitted for a second opinion diagnosis to determine whether the second opinion diagnosis had any influence on patient care. Methods : We reviewed 1,153 outside cytology slides referred to Asan Medical Center for second opinions from January, 2007, to December, 2007. All cases were categorized into three groups; no diagnostic discrepancy, minor diagnostic discrepancies (no impact on the management), and major diagnostic discrepancies (significant impact on the management and subsequent follow-up). Results : The thyroid was the most common organ system (933 cases, 80.9%), Forty cases (3.6%) belonged to the major diagnostic discrepancy group and 149 cases (12.8%) to the minor discrepancy group. For validation of second opinion diagnoses in major discrepancy cases, subsequent biopsy or surgical resection specimens and clinical information were reviewed, which were available in 29 cases. The second opinion diagnoses resulted in alteration of clinical management in 21 of 29 cases. Conclusion : For all referred patients, second opinion diagnosis is important and mandatory for appropriate patient care.

Experimental studies on impact damage location in composite aerospace structures using genetic algorithms and neural networks

  • Mahzan, Shahruddin;Staszewski, Wieslaw J.;Worden, Keith
    • Smart Structures and Systems
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    • 제6권2호
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    • pp.147-165
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    • 2010
  • Impact damage detection in composite structures has gained a considerable interest in many engineering areas. The capability to detect damage at the early stages reduces any risk of catastrophic failure. This paper compares two advanced signal processing methods for impact location in composite aircraft structures. The first method is based on a modified triangulation procedure and Genetic Algorithms whereas the second technique applies Artificial Neural Networks. A series of impacts is performed experimentally on a composite aircraft wing-box structure instrumented with low-profile, bonded piezoceramic sensors. The strain data are used for learning in the Neural Network approach. The triangulation procedure utilises the same data to establish impact velocities for various angles of strain wave propagation. The study demonstrates that both approaches are capable of good impact location estimates in this complex structure.

Free vibration and buckling analysis of the impacted hybrid composite beams

  • Ergun, Emin;Yilmaz, Yasin;Callioglu, Hasan
    • Structural Engineering and Mechanics
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    • 제59권6호
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    • pp.1055-1070
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    • 2016
  • The aim of this experimental study is to investigate the free vibration and buckling behaviors of hybrid composite beams having different span lengths and orientation angles subjected to different impact energy levels. The impact energies are applied in range from 10 J to 30 J. Free vibration and buckling behaviors of intact and impacted hybrid composite beams are compared with each other for different span lengths, orientation angles and impact levels. In free vibration analysis, the first three modes of hybrid beams are considered and natural frequencies are normalized. It is seen that first and second modes are mostly affected with increasing impact energy level. Also, the fundamental natural frequency is mostly affected with the usage of mold that have 40 mm span length (SP40). Moreover, as the impact energy increases, the normalized critical buckling loads decrease gradually for $0^{\circ}$ and $30^{\circ}$ oriented hybrid beams but they fluctuate for the other beams.

브랜드자산과 소비자행동의 관계 (The Relation of Brand Equity and Consumer Behavior.)

  • 김세환
    • 산업융합연구
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    • 제8권1호
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    • pp.1-18
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    • 2010
  • The purpose of this study is to examine the impacts of sports marketing mix factors on brand equities and consumer behaviors. The findings of this study are as follows: first, there are differences in sports marketing mix factors, depending on individual characteristics. Differences are found in gender and living standard with regard to individual characteristics and prices. second, there are differences in brand equities, according to individual characters. third, sports marketing mix factors impact brand equities. fourth, the sports marketing mix factors impact perceive quality, brand recognition, location related to brand image and products. fifth, sports marketing mix factors impact brand equities and consumer behaviors. In regards with brand equities and repeat purchases, sports marketing mix factors impact promotion, products, perceived quality and image. In satisfaction, the sports marketing mix factors impact location, price promotion and product recognition. In the intention of transmission by word of mouth, the factors impact price, products, perceive quality and image.

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벌크 아몰퍼스 금속의 충격파괴 거동 평가를 위한 미소 샬피 시험편을 사용한 계장화 충격 시험법 (Instrumented Impact Test using Subsize Charpy Specimen for Evaluating Impact Fracture Behavior in Bulk Amorphous Metals)

  • 신형섭;고동균;정영진;오상엽;김문생
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.101-106
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    • 2003
  • In order to investigate the mechanical behavior of newly developed materials, the evaluation of mechanical properties using small-size specimen is essential. For those purposes, an instrumented impact testing apparatus, which provides the load-displacement curve under impact loading without oscillations, was devised. To develop the test procedure with the setup, the impact behaviors of various kinds of structural materials such as S45C, SCM4, Ti alloys (Ti-6V-4Al) and Zr-based bulk amorphous metal, were investigated through the instrumented Charpy V-notch impact tests. The calibrations of the dynamic load and displacement that was calculated based on the Newton' second law were carried out through the quasi-static load test and the comparison of a directly measured value using a laser displacement meter. Satisfactory results could be obtained. The crack initiation and propagation processes during impact fracture could be well divided on the curve, depending on the intrinsic characteristic of specimen tested; ductile or brittle. The absorbed impact energy in Zr-basd BAM was largely used for crack initiation not for crack propagation process. The fracture surfaces under impact loading showed different feature when compared with the static cases.

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도로곡선반경에 따른 가변전광표지의 교통안전효과 분석 (An Analysis of Safety Impacts of Variable Message Signage as Functions of Road Curve Radius)

  • 이상혁;조혜진
    • 한국도로학회논문집
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    • 제17권5호
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    • pp.47-56
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    • 2015
  • PURPOSES: The purpose of this study is to estimate the impact of variable message signage (VMS) on traffic safety as a function of road curve radius using statistical methods. METHODS: In order to analyze the impact of VMS installations on traffic safety, travel speed, lateral distance, and geometric data relating to road curvature in each study area was acquired and analyzed for the impact of providing VMS information on driver performance and traffic safety using statistical methods including student t-test, Mann-Whitney test, and the Anderson-Darling test for estimating traffic safety hazard zone in each lane. RESULTS: As a result of analyzing driver performance characteristics before and after providing VMS information, it was determined that by providing VMS information, mean travel speed is deceased and vehicles are driven with increased precision, following the centerline in the first and second lanes. Also the results of analyzing traffic safety impacts of VMS indicate that traffic safety performance factors in the first lane of the Gapyeong section can, on average, increase in the left and right side of the lane by 19.22% and 68.98%, respectively, and in the case of the second lane, safety impacts, on average, can increase in both sides by 100%. For the Hongcheon section, traffic safety impacts in the first lane, on average, can increase along the left and right sides of the lane by 32.31% and 47.18%, and within the second lane, traffic safety can be increased along the left and right side of the lane by 10.97% and -0.01%, respectively. CONCLUSIONS: Based on the results of this study, the impact on traffic safety obtained by providing VMS information for road sections with smaller curve radii is greater than can be obtained for road sections with larger curve radii.

댐이 하류하천에 미치는 영향권 산정에 관한 연구 (A Study on the Impact Range Calculation at the Downstream of Dam)

  • 박봉진;김현식;정관수;지홍기
    • 한국수자원학회논문집
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    • 제41권10호
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    • pp.1009-1021
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    • 2008
  • 본 연구에서는 댐이 하류하천에 미치는 영향권을 산정하기 위하여 수리 수문적, 지형적, 환경 생태적, 사회적 영향의 4개 지표와 38개 항목을 선정하고, 계층분석법을 적용하여 댐의 영향권 산정 지표와 항목의 중요도를 평가하였다. 댐 영향권 산정 지표의 평가결과는 수리 수문적 영향권이 1순위, 환경 생태적 영향권이 2순위, 지형적 영향권 및 사회적 영향권이 각각 3순위와 4순위 이었으며, 항목의 평가결과는 댐설계방류량이 1순위, 하천의 기본 및 계획홍수량이 2순위, 계획홍수량비가 3순위, 유역면적비가 4순위, 하류댐 배수위가 5순위로 평가되었다. 대청댐의 영향권을 산정한 결과, 댐설계방류량 지표는 47.21 km, 하천계획홍수량 지표는 45.71 km, 유역면적비 지표는 13.94 km로 산정되었다.

Impact resistance efficiency of bio-inspired sandwich beam with different arched core materials

  • Kueh, Ahmad B.H.;Tan, Chun-Yean;Yahya, Mohd Yazid;Wahit, Mat Uzir
    • Steel and Composite Structures
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    • 제44권1호
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    • pp.105-117
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    • 2022
  • Impact resistance efficiency of the newly designed sandwich beam with a laterally arched core as bio-inspired by the woodpecker is numerically investigated. The principal components of the beam comprise a dual-core system sandwiched by the top and bottom laminated CFRP skins. Different materials, including hot melt adhesive, high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), epoxy resin (EPON862), aluminum (Al6061), and mild carbon steel (AISI1018), are considered for the side-arched core layer of the beam for impact efficiency assessment. The aluminum honeycomb takes the role of the second core. Contact force, stress, damage formation, and impact energy for beams equipped with different materials are examined. A diversity in performance superiority is noticed in each of these indicators for different core materials. Therefore, for overall performance appraisal, the impact resistance efficiency index, which covers several chief impact performance parameters, of each sandwich beam is computed and compared. The impact resistance efficiency index of the structure equipped with the AISI1018 core is found to be the highest, about 3-10 times greater than other specimens, thus demonstrating its efficacy as the optimal material for the bio-inspired dual-core sandwich beam system.