• 제목/요약/키워드: Moment prior

검색결과 67건 처리시간 0.027초

A Study on the Prediction Analysis of Aviation Passenger Demand after Covid-19

  • Jin, Seong Hyun;Jeon, Seung Joon;Kim, Kyoung Eun
    • 한국항공운항학회지
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    • 제28권4호
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    • pp.147-153
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    • 2020
  • This study analyzed the outlook for aviation demand for the recovery of the aviation industry, focusing on airlines facing difficulties in management due to the Covid-19 crisis. Although the timing of the recovery in aviation demand is uncertain at the moment, this study is based on prior research related to Covid-19 and forecasts by aviation specialists, and analyzed by SWOT technique to a group of aviation experts to derive and suggest implications for the prospects of aviation demand. Looking at the implications based on the analysis results, first, customer trust to prevent infection should be considered a top priority for recovering aviation demand. Second, promote reasonable air price policy. Finally, it seeks to try various research and analysis techniques to predict long-term aviation demand to overcome Covid-19.

모멘트 정보와 표면거리 기반 다중 모달리티 의료영상 정합 (Multi-modality MEdical Image Registration based on Moment Information and Surface Distance)

  • 최유주;김민정;박지영;윤현주;정명진;홍승봉;김명희
    • 한국정보과학회논문지:시스템및이론
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    • 제31권3_4호
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    • pp.224-238
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    • 2004
  • 다중 모달리티 영상정합은 서로 다른 성격의 두 영상의 중요정보를 결합하여 복합적 정보를 얻기 위해 널리 사용되는 영상처리 기법이다. 본 연구에서는 정합 대상 객체의 초기위치 및 방향에 종속적이지 않고, 낮은 정합오차 범위 내에서의 안정적인 정합을 지원하기 위하여 기존의 표면기반 정합 기법을 개선한 모멘트 정보 및 표면거리 기반의 정합 기법을 제시한다. 제안방법에서는 우선 정합대상객체의 표면 윤곽 점을 추출하고, 이를 기반으로 대상객체의 모멘트 정보를 추출하여, 표면거리 기반 상세 정합 이전에 모멘트 정보를 일치시키는 변환을 수행함으로써, 정합이전 대상객체의 위치 및 방향이 상이한 경우에 있어서도 정합이 안정적으로 수행되도록 한다. 또한 테스트 영상에 대한 표면 대표점 추출 시, 표면 코너추출법을 적용함으로써, 기존 표면 정보 기반 정합기법에서 일반적으로 사용하고 있는 무작위 샘플링 및 일정간격 샘플링에 의한 취약점을 보완한다. 본 논문에서 제안기법의 검증을 위하여 뇌 부위 자기공명단층영상(MRI)과 양자 방출 단층 촬영 영상(PET)을 적용하고, 정합오류율과 정합결과에 대한 2,3차원 가시화 영상의 육안평가를 통하여 정확성 및 안정성 측면을 검증한다.

Cyclic behavior of steel I-beams modified by a welded haunch and reinforced with GFRP

  • Egilmez, O. Ozgur;Alkan, Deniz;Ozdemir, Timur
    • Steel and Composite Structures
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    • 제9권5호
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    • pp.419-444
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    • 2009
  • Flange and web local buckling in beam plastic hinge regions of steel moment frames can prevent beam-column connections from achieving adequate plastic rotations under earthquake-induced forces. Reducing the flange-web slenderness ratios (FSR/WSR) of beams is the most effective way in mitigating local member buckling as stipulated in the latest seismic design specifications. However, existing steel moment frame buildings with beams that lack the adequate slenderness ratios set forth for new buildings are vulnerable to local member buckling and thereby system-wise instability prior to reaching the required plastic rotation capacities specified for new buildings. This paper presents results from a research study investigating the cyclic behavior of steel I-beams modified by a welded haunch at the bottom flange and reinforced with glass fiber reinforced polymers at the plastic hinge region. Cantilever I-sections with a triangular haunch at the bottom flange and flange slenderness ratios higher then those stipulated in current design specifications were analyzed under reversed cyclic loading. Beam sections with different depth/width and flange/web slenderness ratios (FSR/WSR) were considered. The effect of GFRP thickness, width, and length on stabilizing plastic local buckling was investigated. The FEA results revealed that the contribution of GFRP strips to mitigation of local buckling increases with increasing depth/width ratio and decreasing FSR and WSR. Provided that the interfacial shear strength of the steel/GFRP bond surface is at least 15 MPa, GFRP reinforcement can enable deep beams with FSR of 8-9 and WSR below 55 to maintain plastic rotations in the order of 0.02 radians without experiencing any local buckling.

Parental Experiences with Chemotherapy-Induced Alopecia among Childhood Cancer Patients in Indonesia

  • Gunawan, Stefanus;Broeke, Chloe ten;Ven, Peter van de;Arnoldussen, Marijn;Kaspers, Gertjan;Mostert, Saskia
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권4호
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    • pp.1717-1723
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    • 2016
  • Background: This study assessed parental experiences with chemotherapy-induced alopecia among children with cancer treated at an Indonesian academic hospital. Materials and Methods: Fifty parents of childhood cancer patients were interviewed using semi-structured questionnaires. Results: The moment that hair fell out was the moment that parents (84%) had to admit their child had cancer. Alopecia was a traumatizing painful experience (46%). Active strategies to hide alopecia, mainly hats, were used by 66% of children, while 34% never covered their bald head. If money had not been an issue, 40% would use another strategy. Alopecia made children limit outdoor daily activities (78%) and engagement with others (60%). Significantly more children from high-educated (95%) than low-educated (60%) parents received sympathy from other people (P=0.012). Significantly more Christian (29%) than Muslim (0%) families confirmed that alopecia lowered the quality of life (P=0.046). Most parents (82%) had no prior plans about alopecia management, yet for significantly more girls (26%) than boys (0%) such plans existed (P=0.044). Parents received most information about alopecia from other parents (66%). Parents (92%) needed more alopecia education from doctors. Of all school-attending children, 53% were bullied and 47% did not want to attend school due to alopecia. Significantly more high-educated than low-educated families received pity from teachers and pupils (94% vs. 0%, P=0.004), and acceptance by pupils (81% vs. 0%, P=0.021). Conclusions: Alopecia is a severe, far-stretching side-effect of chemotherapy with physical, psychological and social consequences for children and parents. Parents should be better informed about occurrence and impact of alopecia. Extra attention is required to facilitate children's return to school. Healthcare providers should facilitate optimal supportive care through open dialogue and provision of educational m aterials for parents, children and their community.

사용중 PSC-I 거더 철도 교량의 휨모멘트에 대한 신뢰도 분석 (Flexural Reliability Assessment of PSC-I Girder Rail Bridge Under Operation)

  • 김기현;여인호;심형보
    • 한국철도학회논문집
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    • 제19권2호
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    • pp.187-194
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    • 2016
  • 철도교량의 신뢰도 기반 한계상태설계법 도입 시 목표신뢰도지수 산정을 위하여 기존 철도교량의 신뢰도지수 산정이 선행되어야 한다. 대표적인 복선 철도교량 중 하나인 6주형 PSC-I형 거더교량에 대해 신뢰도지수를 산정하였다. 최외측 거더의 휨모멘트에 대한 신뢰도 해석을 수행하였다. 휨저항강도 및 고정하중효과는 도로교 한계상태설계법 도입 시 적용된 선행연구자들의 평균과 변동계수를 활용하였고, 열차의 활하중 효과는 여객/화물 혼용선 중 중량화차 통행이 빈번한 중앙선에서 현장계측 데이터를 활용하였다. 한계상태방정식에 대하여 개선된 일계이차 모멘트법(AFOSM)으로 신뢰도 분석을 수행하였으며, 하중효과와 저항효과의 각 요소가 신뢰도지수에 미치는 민감도를 분석하여 중요도를 검토하였다.

The responses of battered pile to tunnelling at different depths relative to the pile length

  • Mukhtiar Ali Soomro;Naeem Mangi;Dildar Ali Mangnejo;Zongyu Zhang
    • Geomechanics and Engineering
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    • 제35권6호
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    • pp.603-615
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    • 2023
  • Population growth and urbanization prompted engineers to propose more sophisticated and efficient transportation methods, such as underground transit systems. However, due to limited urban space, it is necessary to construct these tunnels in close proximity to existing infrastructure like high-rise buildings and bridges. Battered piles have been widely used for their higher stiffness and bearing capacity compared to vertical piles, making them effective in resisting lateral loads from winds, soil pressures, and impacts. Considerable prior research has been concerned with understanding the vertical pile response to tunnel excavation. However, the three-dimensional effects of tunnelling on adjacent battered piled foundations are still not investigated. This study investigates the response of a single battered pile to tunnelling at three critical depths along the pile: near the pile shaft (S), next to the pile (T), and below the pile toe (B). An advanced hypoplastic model capable of capturing small strain stiffness is used to simulate clay behaviour. The computed results reveal that settlement and load transfer mechanisms along the battered pile, resulting from tunnelling, depend significantly on the tunnel's location relative the length of the pile. The largest settlement of the battered pile occurs in the case of T. Conversely, the greatest pile head deflection is caused by tunnelling near the pile shaft. The battered pile experiences "dragload" due to negative skin friction mobilization resulting from tunnel excavation in the case of S. The battered pile is susceptible to induced bending moments when tunnelling occurs near the pile shaft S whereas the magnitude of induced bending moment is minimal in the case of B.

포스트 텐션 플랫 플레이트 외부 접합부의 내진 거동 (Seismic Behaviour of Exterior Joints in Post-Tensioned Flat Plate Systems)

  • 한상환;기성훈;강현구;조종;이리형
    • 콘크리트학회논문집
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    • 제18권5호
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    • pp.595-602
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    • 2006
  • 본 연구의 목적은 중력 하중에 저항하도록 설계된 플랫 플레이트 외부 접합부의 이력 거동을 평가하는 데 있다. 이러한 목적을 위하여 2/3의 크기가 조정된 PT 슬래브-기둥 외부 접합부 2개와 RC 슬래브-기둥 외부 접합부 1개를 대상으로 실험적 연구를 수행하였다. 여기서 각각의 PT 실험체는 서로 다른 강선 배치 형태를 띄고 있다. 중력 하중은 동일하게 설정하였고, 지속적인 정적 하중 하에서 유사 정적 횡하중을 적용하였다. 한편 모든 실험체는 ACI 318-05과 ACI 352.1R-89에 근거하여 기둥 폭 내에 하부 철근을 배근 하였다. 또한 PT 외부 접합부의 이력 거동에 대한 일반적인 결론을 얻기 위하여 기존 연구자들의 실험 결과와 함께 비교하였다. 이번 연구를 통하여 강선의 배치는 PT 접합부의 이력 거동을 결정하는 중요한 변수임을 확인하였다. 즉 횡변형 성능, 에너지 소산 능력, 파괴 메커니즘, 그리고 연성 능력이 강선의 배치에 따라 다르게 나타났다. 또한 ACI 352.1R-89에서 구조적 일체성을 위해 제공된 하부 철근의 양은 모멘트 역전에 의해 발생된 정모멘트를 저항하는데 있어서도 적절하다는 것이 밝혀졌다. 또한 실험체의 전단 강도는 강선의 포스트 텐션에 의한 평균 콘크리트 압축 응력($f_{pc}$)의 효과가 고려된 식이 그렇지 않은 식보다 전단 강도를 정확히 예측하는 것으로 나타났다.

의복 착장 과정 및 착장 만족도에 대한 탐색적 연구 (The Exploratory Study on Daily Grooming Process and Outfit Satisfaction)

  • 이하경
    • 한국의류학회지
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    • 제42권2호
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    • pp.311-326
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    • 2018
  • The satisfaction of wearing an outfit in daily life can lead to the attitude toward the clothes and further the brand image and repeat purchases; however, satisfaction generated from the moment the outfit was purchased is only temporary. Therefore, it would be necessary to study the antecedent variables that precede daily outfit satisfaction. In the current study, to understand the antecedent variables that influence the daily outfit satisfaction of consumers, in-depth interviews were conducted on thirteen women in their 20s and 30s. The results showed that peoples' outfit satisfaction was dependent on a comparison between their prior expectation and the performance of the outfit based on expectation-performance disconfirmation. The outfit performance was evaluated by themselves or others. Simultaneously, it was found that the others' opinion on the clothes and surroundings influence daily outfit satisfaction. This research helps deepen the understanding on the individual and social influential factors of the temporary satisfaction from purchase to the satisfaction of actually using clothes. This result ultimately intensifies the understanding on the consumption and evaluation of clothes in the whole life cycle of clothing products from purchase to disposal.

WAVELET-BASED FOREST AREAS CLASSIFICATION BY USING HIGH RESOLUTION IMAGERY

  • Yoon Bo-Yeol;Kim Choen
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.698-701
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    • 2005
  • This paper examines that is extracted certain information in forest areas within high resolution imagery based on wavelet transformation. First of all, study areas are selected one more species distributed spots refer to forest type map. Next, study area is cut 256 x 256 pixels size because of image processing problem in large volume data. Prior to wavelet transformation, five texture parameters (contrast, dissimilarity, entropy, homogeneity, Angular Second Moment (ASM≫ calculated by using Gray Level Co-occurrence Matrix (GLCM). Five texture images are set that shifting window size is 3x3, distance .is 1 pixel, and angle is 45 degrees used. Wavelet function is selected Daubechies 4 wavelet basis functions. Result is summarized 3 points; First, Wavelet transformation images derived from contrast, dissimilarity (texture parameters) have on effect on edge elements detection and will have probability used forest road detection. Second, Wavelet fusion images derived from texture parameters and original image can apply to forest area classification because of clustering in Homogeneous forest type structure. Third, for grading evaluation in forest fire damaged area, if data fusion of established classification method, GLCM texture extraction concept and wavelet transformation technique effectively applied forest areas (also other areas), will obtain high accuracy result.

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프랑스이 호텔 및 식당등급 제도 및 평가서 비교 연구 -정부 주도 등급제도, Michelin의 "Guide rouge"Gault-Millau의 "Guide France"를 중심으로- (A comparative study on the rating system of hotels and restaurants in France (The system of gouvernment, "Guide rouge"of Michelin and "Guide France"of Gault-Millau)

  • 김동승;이상정
    • 한국관광식음료학회지:관광식음료경영연구
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    • 제9권
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    • pp.67-91
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    • 1998
  • This study reviews the rating system of hotels and restaurants regulated by french gouvernment and compares the french guide books of worldwide reputaion : Guide rouge of Michelin and Guide France of Gault-Millau. The apparatus of gouvernment and the inspectors deciding the grades, the processes and the prior conditions needed for obtaining the adequate grades are mentioned. So it will be a help to understand the present system of hotels and restaurants in France. The publishing firms like Michelin and Gault-Millau not only encourage the trvel and F & B industry by estimating the hotels and restaurants and publishing the results, but also informe the consumer. Ultimately, the guide books would like to play an important role in improving or making better the levels of the tourism and the gastronomy. They support continuously the publishing of guide books with the qualified persons and financial aid. Especially, Michelin doesn't insert the advertisement in his publications. In publishing the guide books, it can be one of the most important points for proving his independence of hoteliers, restaurateurs and the others. The seconde point is impartial, clear and rigid inspection that doesn't admit any corruption. Now is the moment in korea to promote the tourism and the gastronomy by publishing the credible books like 「Guide rouge」 and 「Guide France」in order to present Korean attrations and epicurean foods.

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