• 제목/요약/키워드: Tsukuba

검색결과 446건 처리시간 0.026초

On the genus Rhodella, the emended orders Dixoniellales and Rhodellales with a new order Glaucosphaerales (Rhodellophyceae, Rhodophyta)

  • Scott, Joe;Yang, Eun-Chan;West, John A.;Yokoyama, Akiko;Kim, Hee-Jeong;De Goer, Susan Loiseaux;O'Kelly, Charles J.;Orlova, Evguenia;Kim, Su-Yeon;Park, Jeong-Kwang;Yoon, Hwan-Su
    • ALGAE
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    • 제26권4호
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    • pp.277-288
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    • 2011
  • The marine unicellular red algal genus Rhodella was established in 1970 by L. V. Evans with a single species R. maculata based on nuclear projections into the pyrenoid. Porphyridium violaceum was described by P. Kornmann in 1965 and transferred to Rhodella by W. Wehrmeyer in 1971 based on plastid features and the non-parietal position of the nucleus. Molecular and fine structural evidences have now revealed that Rhodella maculata and R. violacea are one species, so R. violacea has nomenclatural priority and the correct name is Rhodella violacea (Kornmann) Wehrmeyer. The status of families within Rhodellophyceae was examined. The order Dixoniellales and family Dixoniellaceae are emended to include only Dixoniella and Neorhodella. The order Rhodellales and family Rhodellaceae are emended to include Rhodella and Corynoplastis. Glaucosphaera vacuolata Korshikov and the Glaucosphaeraceae Skuja (1954) with an emended description are transferred to the Glaucosphaerales ord. nov.

Evaluation of Computational Fluid Dynamics for Analysis of Aerodynamics in Naturally Ventilated Multi-span Greenhouse

  • Lee, In Bok;Short, Ted H.;Sase, Sadanori;Lee, Seung Kee
    • Agricultural and Biosystems Engineering
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    • 제1권2호
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    • pp.73-80
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    • 2000
  • Aerodynamics in a naturally ventilated multi-span greenhouse with plants was analyzed numerically by the computational fluid dynamics (CFD) simulation. To investigate the potential application of CFD techniques to greenhouse design and analysis, the numerical results of the CFD model were compared with the results of a steady-state mass and energy balance numerical model. Assuming the results of the mass and energy balance model as the standard, reasonably good agreement was obtained between the natural ventilation rates computed by the CFD numerical model and the mass and energy balance model. The steady-state CFD model during a sunny day showed negative errors as high as 15% in the morning and comparable positive errors in the afternoon. Such errors assumed to be due to heat storage in the floor, benches, and greenhouse structure. For a west wind of 2.5 m s$^{-1}$ , the internal nonporous shading screens that opened to the east were predicted to have a 15.6% better air exchange rate than opened to the west. It was generally predicted that the presence of nonporous internal shading screens significantly reduced natural ventilation if the horizontal opening of the screen for each span was smaller that the effective roof vent opening.

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An Application of GP-based Prediction Model to Sunspots

  • Yano, Hiroshi;Yoshihara, Ikuo;Numata, Makoto;Aoyama, Tomoo;Yasunaga, Moritoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.523-523
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    • 2000
  • We have developed a method to build time series prediction models by Genetic Programming (GP). Our proposed CP includes two new techniques. One is the parameter optimization algorithm, and the other is the new mutation operator. In this paper, the sunspot prediction experiment by our proposed CP was performed. The sunspot prediction is good benchmark, because many researchers have predicted them with various kinds of models. We make three experiments. The first is to compare our proposed method with the conventional methods. The second is to investigate about the relation between a model-building period and prediction precision. In the first and the second experiments, the long-term data of annual sunspots are used. The third is to try the prediction using monthly sunspots. The annual sunspots are a mean of the monthly sunspots. The behaviors of the monthly sunspot cycles in tile annual sunspot data become invisible. In the long-term data of the monthly sunspots, the behavior appears and is complicated. We estimate that the monthly sunspot prediction is more difficult than the annual sunspot prediction. The usefulness of our method in time series prediction is verified by these experiments.

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NDVI RESPONSES TO THE FOREST CANOPY AND FLOOR IN EASTERN SIBERIA

  • Suzuki, Rikie;Kobayashi, Hideki;Delbart, Nicolas;Hiyama, Tetsuya;Asanuma, Jun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.325-328
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    • 2007
  • We discuss the Normalized Difference Vegetation Index (NDVI) of the forest canopy and floor separately based on airborne spectral reflectance measurements and simultaneous airborne land surface images acquired around Yakutsk, Siberia in 2000. The aerial land surface images were visually classified into four forest types: no-green canopy and snow floor (Type-1), green canopy and snow floor (Type-2), no-green canopy and no-snow floor (Type-3), and green canopy and no-snow floor (Type-4). The mean NDVI was calculated for these four types. Although Type-2 had green canopy, the NDVI was rather small (0.17) because of high reflection from the snow cover on the floor. Type-3, which had no green canopy, indicated considerably large NDVI (0.45) due to the greenness of the floor. Type-4 had the largest NDVI (0.75) because of the greenness of both the canopy and floor. These results reveal that the NDVI depends considerably on forest floor greenness and snow cover in addition to canopy greenness.

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과 부영양형 호수의 유기물 변동에 따른 박테리아 군집의 그램 염색 특성 (The Gram-Stain Characteristics of the Bacterial Community as a Function of the Dynamics of Organic Debris in a Hypereutrophic Lake)

  • 강헌
    • 한국해양학회지
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    • 제24권3호
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    • pp.148-156
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    • 1989
  • 본 연구는 여러 수생생태계에서 유기물의 동적순환에 따른 부유성 박테리아와 부착성 박테리아의 그램염색(gram-stain) 특성을 알아보기 위한 일련의 시도로서 일본에서 두번째로 크며 부영양화가 상당히 진전된 가스미가우라 호수에서 1년간, 매주 실시했다. 이 전형적인 부영양형(eutrophic) 수생생태계의 박테리아군집의 그램염색 특성은 중영양형(mesotrophic) 환경과 같이 유기물의 유입에 따라 변화함을 보여준다. 그램음성(negative) 박테리아군집은 부유성 박테리아군집이 약 57%, 부착성 박테리아군집이 약 53%이며, 두 군집의 통계분석은 서로 다른 특성을 보여준다. 부착성 박테리아군집은 그램 양성, 음성 모두 쇄설성 유기물 형성과 분해에 영향을 미친다. 또한 그램 음성 부유박테리아는 특히 용존 유기물의 동적순환에 관여한다.

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Ni과잉 Ti-Ni 합금의 형상기억특성 및 피로 특성에 미치는 시효처리의 영향 (Effects of Aging Treatment on Shape Memory and Fatigue Properties in Ni-rich Ti-Ni Alloy)

  • 김재일;성장현;미야자키 슈이치;이상화
    • 열처리공학회지
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    • 제20권1호
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    • pp.11-16
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    • 2007
  • The fatigue properties of Ti-Ni shape memory alloy wires were investigated. In Ni-rich Ti-Ni shape memory alloys, $Ti_3Ni_4$ precipitates formed by aging treatments are believed to vary the shape memory and mechanical properties. In this study, the effect of aging temperature and aging time on shape memory properties and fatigue life were investigated using Ti-50.9 at% Ni alloy wires. The specimens were solution-treated at 1073 K for 3.6 ks followed by aging at 573 K, 673 K and 773 K for periods between 3.6 ks and 3600 ks. It was found that the fatigue life under a constant stress decreased with increasing aging temperature. When the specimens were aged at 573 K for periods between 36 ks and 360 ks, superior shape memory and fatigue properties were obtained. The fatigue life also decreased when the test temperature and strain amplitude increased. It was concluded that the fatigue life exhibited a linear relationship with the critical stress for slip.

An Analysis Code and a Planning Tool Based on a Key Element Index for Controlled Explosive Demolition

  • Isobe, Daigoro
    • 국제초고층학회논문집
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    • 제3권4호
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    • pp.243-254
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    • 2014
  • In this study, a demolition analysis code using the adaptively shifted integration (ASI)-Gauss technique, which describes structural member fracture by shifting the numerical integration point to an appropriate position and simultaneously releasing the sectional forces in the element, is developed. The code was verified and validated by comparing the predicted results with those of several experiments. A demolition planning tool utilizing the concept of a key element index, which explicitly indicates the contribution of each structural column to the vertical load capacity of the structure, is also develped. Two methods of selecting specific columns to efficiently demolish the whole structure are demonstrated: selecting the columns from the largest index value and from the smallest index value. The demolition results are confirmed numerically by conducting collapse analyses using the ASI-Gauss technique. The numerical results suggest that to achieve a successful demolition, a group of columns with the largest key element index values should be selected when explosives are ignited in a simultaneous blast, whereas those with the smallest should be selected when explosives are ignited in a sequence, with a final blast set on a column with large index value.

Profenofos에 대한 집파리(Musca domestica L.) 저항성 유전자의 연쇄군 해석 (Linkage Group Analysis of Profenofos Resistance in the Housefly(Diptera: Mucsidae))

  • 박정규;정야준부;안용준
    • 한국응용곤충학회지
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    • 제35권2호
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    • pp.159-163
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    • 1996
  • 유기인체 살충제인 Pyraclofos에 저항성인 집파리를 profenofs로 7세대 도태시킨 P-Pro 계통을 이용하여 Pro-fenofos 저항성의 유전학적인 분석을 행하였다. Profenofos저항성은 불완전우성으로 나타났기 때문에 가시돌연변이로 각 염색체를 표식한 감수성 ac;ar;bwb;ye;snp 계통을 이용하여 $F_1$male-backcross에의한 연쇄군분석을 한 결과, 이 계통의 profenofos 저항성의 우성유전자는 각 염색체에 고루 존재하지만 제 2 염색체와제 5염색체 상의 유전자에 크게 지배받으면 웅성결정인자 M은 제 3염색체와 관련이 있는 것으로 나타났다.

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Information Professionals' Knowledge Sharing Practices in Social Media: A Study of Professionals in Developing Countries

  • Islam, Anwarul;Tsuji, Keita
    • International Journal of Knowledge Content Development & Technology
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    • 제6권2호
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    • pp.43-66
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    • 2016
  • The primary objective of this study was to investigate the perception of informational professionals' knowledge sharing practices in social media platforms. The specific objectives of the study included learning professionals' perceptions and awareness of knowledge sharing using social media, understanding their opinions and beliefs, and gaining familiarity with and reasons for using these tools. Open & close ended web-based questions were sent out by email to the international training program (ITP) participants. Findings indicated that most of the respondents' were aware of using social media and that they used social media for knowledge sharing. Speed and ease of use, managing personal knowledge, easier communication with users and colleagues and powerful communication tool are the areas that motivated them to use it. It also stated some barriers like lack of support, familiarity, trust, unfiltered information and fear of providing information. The study was limited to the perceptual aspect of the issue, specifically from the individuals' opinions and sentiments.

지표면 열수지의 강수응답성에 관한 연구 (The Response of soil surface heat budget to the precipitation)

  • 황수진;진병화
    • 한국환경과학회지
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    • 제3권2호
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    • pp.89-100
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    • 1994
  • It is very important to assess accurately the terms which are included in the heat budget equation of soil surface because they are used in the UM and miso-scale circulation modeling as well as in the micrometeorological studies. Each terms in the heat budget equation change according to the soil moisture content. So, it is necessary to specify clearly the relations between soil moisture content and these terms. Special experiment with micrometeorological measurements was executed to study these relations at Environmental Research Center of Tsukuba University, Japan. The results are as follow: 1. The soil moisture contents of 1 cm and 4 cm depth are oscillated with one day Period in drying process and the amplitude of variation of 1 cm depth is greater than that of 4 cm. 2. Increase in soil moisture contents due to precipitation result in decrease of albedo with step function. 3. Sensible heat is in reverse proportion to the soil moisture content and latent heat is in direct proportion to it. Latent heat is more sensitive than sensible heat according to the soil moisture variation. Net long wave radiation have high correlation with soil moisture. 4. Comparing with the radiative term with the flux term in wetting process due to precipitation, the energy transfer of the aero and thermodynamic flux is greater than that of the radiative heat flux.

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