• 제목/요약/키워드: Unfavorable pattern

검색결과 58건 처리시간 0.031초

Numerical analysis of a long-span bridge response to tornado-like winds

  • Hao, Jianming;Wu, Teng
    • Wind and Structures
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    • 제31권5호
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    • pp.459-472
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    • 2020
  • This study focused on the non-synoptic, tornado-like wind-induced effects on flexible horizontal structures that are extremely sensitive to winds. More specifically, the nonuniform, intensive vertical wind-velocity and transient natures of tornado events and their effects on the global behavior of a long-span bridge were investigated. In addition to the static part in the modeling of tornado-like wind-induced loads, the motion-induced effects were modeled using the semi-empirical model with a two-dimensional (2-D) indicial response function. Both nonlinear wind-induced static analysis and linear aeroelastic analysis in the time domain were conducted based on a 3-D finite-element model to investigate the bridge performance under the most unfavorable tornado pattern considering wind-structure interactions. The results from the present study highlighted the important effects due to abovementioned tornado natures (i.e., nonuniform, intensive vertical wind-velocity and transient features) on the long-span bridge, and hence may facilitate more appropriate wind design of flexible horizontal structures in the tornado-prone areas.

임상가를 위한 특집 1 - Comprehensive approach with implant

  • 이동현
    • 대한치과의사협회지
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    • 제51권11호
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    • pp.586-594
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    • 2013
  • The critical factors affecting the esthetics of anterior implants can be summarized as following: 1) Correct positioning of implant fixture 2) Enough amount of alveolar bone 3) Optimum volume of soft tissue. The position of implant is probably the most important factor in obtaining esthetic treatment outcome. The 3-dimensional orientation of implant is determined by the position on the alveolar ridge and its direction. Clinicians often try to mimic natural teeth when fabricating restorations. During the course of esthetic diagnosis and treatment, however, one should not forget to consider the correlation between facial pattern, lips, gingiva, alveolar ridge, as well as remaining dentition. Since anterior region is biologically unfavorable when compared with posterior region, one minor discrepancy in positioning of implant can cause esthetically undesirable treatment outcome. If one understands the biological and prosthetic meaning of implant's 3-dimensional position, he or she can achieve superior esthetic outcome in anterior region.

RTM 공정에서 기공 최소화를 위한 공정 제어에 관한 연구 (A Study on the Control Strategy to Minimize Voids in Resin Transfer Mold Filling Process)

  • 이도훈;전영재;이우일;엄문광;변준형
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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    • pp.292-296
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    • 2004
  • In case of Resin Transfer Molding(RTM) process, 'race-track' effects and non-uniform fiber volume fraction may cause undesirable resin flow pattern and thus result in dry spots, which affect the mechanical properties of the finished parts. In this study, a real time RTM control strategy to prevent these unfavorable effects is proposed. The control strategy consists of two 'stages' depending on the extent the resin front has reached. Through numerical simulations and experiments, the validity of the proposed scheme is demonstrated. The results show that the proposed scheme is effective in reducing the void formation during RTM mold filling.

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국내 육 가공품의 소비성향에 관한 연구 (Consumption Pattern of Meat Products in Korea)

  • 윤명헌;장경만;최일신
    • 한국축산식품학회지
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    • 제21권1호
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    • pp.18-23
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    • 2001
  • A total of 100 adults were surveyed on types of favorable meat products. They tended to show much of unsatisfactory on the market products. Those unsatisfactory were mostly conceptual such as instant products, unreliable raw materials, sanitation conditions, list of unfavorable ingredients, mix of harmful additives, and etc. The results indicated that the consumers purchased the products of ham, cheese, chicken, sausages, and canned products mostly at medium-large marts(56%), department stores(22%), retail stores(19%) and others(3%). They were also concerned with the distribution date, prices, shape of packaging, and etc. The types of products and frequencies of purchasing various products were varied by time. For the purchase of products, mixed items were more favored rather than the single items.

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광패턴을 이용한 능동형 수위 및 거리 측정 기법 (Active Water-Level and Distance Measurement Algorithm using Light Beam Pattern)

  • 김낙우;손승철;이문섭;민기현;이병탁
    • 전자공학회논문지
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    • 제52권4호
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    • pp.156-163
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    • 2015
  • 본 논문은 광패턴 조사를 통한 능동형 수위 및 거리 측정 기법을 제안한다. 기존 압력식, 부자식, 초음파식, 레이더식 등의 수위측정기법과 달리 최근에는 수위측정의 정확성과 모니터링 편리성을 강조한 영상기반 수위측정기법이 활용되고 있다. 본 논문에서는 참조용 광패턴을 교각이나 제방 등에 동적으로 조사(照射)하고, 카메라 장치로부터 조사된 광패턴 영상을 실시간 분석 처리하여 자동 수위측정 및 조사(照射) 대상물까지의 거리측정을 위한 새로운 방법을 제시한다. 기존 방법이 교각에 기(旣) 부착된 수위표나 마커 인식을 위해 수동적으로 영상데이터를 분석하는 것이었다면, 본 기법은 교각 설치 환경에 대응하여 능동적으로 참조 광패턴을 생성하여 사용함으로써, 난시야(難視野) 환경 및 잡음 대응에 효과적이고, 포터블 형태로 주야간 이용이 가능하며, 별도 조명 설치를 요구하지 않는 등의 강건한 수위 측정을 지원한다. 본 실험은 실내 시험 환경을 구성하여 시뮬레이션 하였으며, 0.4-1.4m 거리 13.5-32.5cm 높이에서 수위 및 거리 측정을 수행하였다.

2-Dimensional inverse opal structured VO2 thin film for selective reflectance adjustment

  • Lee, Yulhee;Yu, Jung-Hoon;Nam, Sang-Hun;Seo, Hyeon Jin;Hwang, Ki-Hwan;Kim, Minha;Lee, Jaehyeong;Boo, Jin-Hyo
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.410.1-410.1
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    • 2016
  • Vanadium dioxide ($VO_2$) is a well-known material that exhibits a metal-semiconductor transition at 340 K, with drastic change of transmittance at NIR region. However, $VO_2$ based thermochromics accompany with low visible transmittance value and unfavorable color (brownish yellow). Herein, we demonstrate the adjustment of visible transmittance of $VO_2$ thin film by nanosphere template assisted patterning process using sol-gel method. 2-Dimenstional honeycomb shape was varied as function of diameter of nanosphere and coating conditions. The morphological geometry of the films was investigated by FE-SEM and AFM. Result shows that inversed shape of nanosphere was formed clearly and pattern width was altered according to the bead size. This structure creates the geometrical blank area from the position of nanosphere which improves the optical transmittance at the visible region. Moreover, such patterned $VO_2$ thin film not only maintains the optical switching efficiency, but also generate the gorgeous scattering effect which presumably support the glazing application.

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Correlation between Serum Carcinoembryonic Antigen Level and Histologic Subtype in Resected Lung Adenocarcinoma

  • Tomita, Masaki;Ayabe, Takanori;Nakamura, Eiichi Chosa Kunihide
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권9호
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    • pp.3857-3860
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    • 2015
  • Background: Recent studies revealed a relationship between ground-glass opacity (GGO) ratio on computed tomography (CT) and serum carcinoembryonic antigen (CEA) level in lung adenocarcinoma. Since an association between lepidic histologic pattern and GGO is well accepted, we investigated the link between histologic subtype and serum CEA level in resected lung adenocarcinoma. Materials and Methods: One hundred and eighty-one consecutive patients with resected lung adenocarcinoma were studied retrospectively. The histologic subtype was subdivided into 2 groups: lepidic dominant histologic subtype, including adenocarcinoma in situ, minimally invasive adenocarcinoma and lepidic predominant invasive adenocarcinoma versus other subtypes. Results: The 5-year survival of patients with s high serum CEA level was significantly more unfavorable than that with normal levels. Similarly, there was also a relationship between the patient survival and histologic subtype, with favorable survival found in patients with the lepidic dominant histologic subtype. There was a significant relationship between serum CEA level and lepidic dominant histologic subtype overall and in p-stage I patients. Conclusions: Lung adenocarcinomas with non-lepidic dominant histologic subtype are associated with high serum CEA levels.

Characterization of full-length enriched expressed sequence tags of dehydration-treated white fibrous roots of sweetpotato

  • Kim, Sun-Hyung;Song, Wan-Keun;Kim, Yun-Hee;Kwon, Suk-Yun;Lee, Haeng-Soon;Lee, In-Chul;Kwak, Sang-Soo
    • BMB Reports
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    • 제42권5호
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    • pp.271-276
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    • 2009
  • Sweetpotato (Ipomoea batatas (L). Lam.) is relatively tolerant to unfavorable growth conditions such as drought, yet has not been exploited to provide a better understanding of the molecular basis of drought stress tolerance. We obtained 983 high-quality expressed sequence tags of 100 bp or longer (average length of 700 bp) from cDNA libraries of detached white fibrous root tissues by subjecting them to dehydration for 6 h. The 431 cDNAs were each assigned a function by alignment using the BLASTX algorithm. Among them, three genes associated with various abiotic stresses and nine genes not previously associated with drought stress were selected for expression pattern analysis through detailed reverse transcription-polymerase chain reaction. The direct and indirect relationships of the 12 genes with drought tolerance mechanisms were ascertained at different developmental stages and under various stress conditions.

벼의 생산력 분석 -[1] 한계 수량- (Analysis of Productivity in Rice Plant -[I] Potential Grain Yield-)

  • 박훈;김영섭;목성균
    • Applied Biological Chemistry
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    • 제14권3호
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    • pp.221-227
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    • 1971
  • 수원 213, 수원 214, 진흥 및 팔달의 한계수량을 각엽위엽의 한계 수량으로부터 계산하였다. 한계수량의 패턴이 각엽의 백분을 기여도에 따라 IR 667계통은 상위엽 의존형인 반면 진흥과 팔달은 하위엽 의존형으로 구분할 수 있었다. 이러한 패턴은 각기 조기노화 및 내음성과 관련될 것으로 추정되었다. 한계수량과 실수랑을 비교한 결과 초형이 비교적 불량한 진흥과 팔달은 보다 더 한계수량에 미달하였다. 한계수량이 갖는 영양생리 및 육종에 있어서의 의의를 검토하였으며 한계수량 측정방법도 논의하였다.

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열대 해수면 온도 분포와 북서태평양 태풍의 계절적 활동 시작일 변동 사이의 관련성 (Relationship between the Tropical Sea Surface Temperature Distribution and Initiation Timing of the Typhoon Season in the Northwestern Pacific)

  • 김동희;김형석
    • 한국기후변화학회지
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    • 제8권1호
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    • pp.11-19
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    • 2017
  • This study examined the relationship between the initiation timing typhoon season in the Northwestern Pacific and the tropical sea surface temperature (SST) using a numerical simulation. The initiation timing of the typhoon season is closely associated with SSTs over the Indian Ocean (IO) and the eastern Pacific (EP) in the preceding winter and early-spring. The experiment based on the Weather and Research Forecast (WRF) model showed that the start date of the typhoon season is delayed for about one month when the SSTs over the IO and the EP increase in the preceding winter. The forced tropical SST pattern induces anticyclonic anomalies in the Northwestern Pacific, which is an unfavorable condition for typhoon development, and hence it could delay the initiation of the typhoon season.