• 제목/요약/키워드: Artificial Distribution

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전남 여수 금오도 인공어초 설치 해역의 해조류 분포 (Seaweed distribution on the area of artificial reefs in Geumo-do, Yeosu)

  • 김철원;정달상
    • 현장농수산연구지
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    • 제17권1호
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    • pp.45-56
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    • 2015
  • 2017년도 여수 금오도에서 패조류 어초설치와 해조번식을 위한 베드장 조성을 위하여 해조류 생물상 조사한 결과 해조류 출현종은 녹조류 4종, 갈조류 9종, 홍조류 15종으로 총 30종이 출현하였으며 현존량도 1600~4000g/m2로 같은 시기의 다른 지역보다 높게 나타났다. 상부인 조간대에서는 출현종수와 우점도가 가장 높게 나타났으며 조하대인 수심 1~3m에서는 해조류 현존량이 높은 것으로 나타났다. 그러나 수심 4~6m의 하부에서는 출현종, 우점도 및 현존량 모두 낮게 나타났다. 본 조사시 나타난 특징은 금오도 지역은 조하대 수심 4~6m권에서 갯녹음현상 발생으로 해조류 군집이 급격이 감소되어 이 해역에 해조류형 어초나 해조배드를 설치하여 자원량을 증강시키는 것이 필요 할 것으로 사료되었다. 또한 해조류형 어초시설의 경우 투하시기는 해조류의 포자가 방출되기 전인 시기인 초봄시기에 시설되는 것이 바람직 할 것으로 생각되며 수심은 보상심도가 유지되는 3~6m권내에 설치 될 수 있도록 하는 것이 효율적이라고 판단된다.

흐름장에서 인공용승구조물의 블록투하 및 용승효과에 관한 실험적 연구 (An Experimental Study for the Falling Test and Upwelling Effect of the Artificial Upwelling Structures in Flow Field)

  • 전용호;이경선;강윤구;류청로
    • 한국해양공학회지
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    • 제21권4호
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    • pp.21-27
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    • 2007
  • The multiplication equipment of marine products with artificial upwelling structures could be useful in the fishing grounds near coastal areas. Artificial upwelling structures could move the inorganic nutrients from the bottom to the surface. Artificial upwelling structures have been used to improve the productivity of fishing grounds. Until now, research on artificial upwelling structures has been related to the distribution of the upwelling region, upwelling structures, and the marine environment. However, little work on the optimum design of the rubber-mound artificial upwelling structures has been done to increase the efficiency of drawing up the inorganic nutrients. This study investigated the optimum cross-section of rubber-mound artificial upwelling structures by means of hydraulic experiments. The hydraulic experiments include the falling test of rubber. Based on the results of the falling test, the relationship between the length of the rubber mound and water velocity, and the relationship between the shape of the rubber and the stratification parameter were established. In addition, the effect of the void ratio of various artificial structures on the stratification parameter was studied. From the experiment, it was found that upwelling could be enhanced when the ratio of structure height to water depth was 0.3 and stratification parameter was 3.0. The upwelling was not improved when the void ratio exceeded 0.43. The optimum size of rubber mounds was determined when the incident velocity was influenced by the mean horizontal length rather than size of block.

Effects of Artificial UV-B and Solar Radiation on Four Species of Antarctic Rhodophytes

  • Han, Tae-Jun;Park, Seon-Joo;Lee, Min-Soo;Han, Young-Seok;Kang, Sung-Ho;Chung, Ho-Sung;Lee, Sang-Hoon
    • Ocean and Polar Research
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    • 제23권4호
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    • pp.389-394
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    • 2001
  • During austral summer 1998 we examined the impacts of artificial UV-B and solar radiation on chlorophyll a content and fresh weight of four species of Antarctic red algae namely, Georgiella confluens, Iridaea cordata, Pantoneura plocamioides and Porphyra endiviifolium. These subject species were taken in consideration of clear demarcations of their vertical distribution and classified as shallow water group (Iridaea and Porphyra) and deep water group (Georgiella and Pantoneura). When irradiated with artificial UV-B at the irradiance of $2.0Wm^{-2}$ the shallow water inhabitants were much more resistant than the algae from deep water the fresh weight of which was reduced by 40-50% relative to control apart from loss of pigmentation. Direct solar radiation was lethal to the deep water group with a sign of complete bleaching whereas the shallow water group did not show any change in the physiological parameters. We were unable to discriminate difference in the algal sensitivity between UV-filtered and UV-transparent treatments since samples tested were either all unaffected or dead. Spectrophotometric measurements of methanolic extracts revealed a strong absorption peak in the UV range in the shallow water group of algae, Iridaea and Porphyra, but not in the deep water counterparts. Species difference in sensitivity to artificial UV-B and solar radiation is discussed in relation to biochemical and morphological characteristics and the role of the radiation in the algal vertical distribution is suggested from ecological perspective.

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LDA와 LSTM를 응용한 뉴스 기사 기반 선물가격 예측 (Futures Price Prediction based on News Articles using LDA and LSTM)

  • 주진현;박근덕
    • 산업융합연구
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    • 제21권1호
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    • pp.167-173
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    • 2023
  • 경제지표를 분석하는 방법으로 회귀 분석이나, 인공지능을 활용하여 미래의 데이터를 예측하는 연구가 발표되었다. 본 연구에서는 토픽모델링을 사용하여 과거 뉴스 기사로부터 얻은 주제 확률 데이터를 이용한 인공지능으로 미래 선물 가격을 예측하는 시스템을 구상하였다. 과거 뉴스 기사로부터 비지도학습을 통한 문서의 주제를 추출할 수 있는 LDA 방법으로 각 뉴스 기사 주제 확률 분포 데이터를 얻을 수 있고, 해당 데이터를 인공지능의 RNN의 파생 구조인 LSTM의 입력 데이터로 활용함으로써 미래 선물 가격을 예측하였다. 본 연구에서 제안한 방법에서는 선물 가격의 추세를 예측할 수 있었고, 이를 활용하여 추후 옵션 상품 등의 파생 상품에 대한 가격 추세도 예측할 수 있을 것으로 보인다. 다만, 일부 데이터에 대해 오차가 발생하는 것이 확인되어 정확도 향상을 위한 추가적인 연구가 필요하다.

Distribution Competitive Advantage of Vietnamese Fintech Enterprises and its Impact on Dynamic Capabilities

  • Nguyen Van THUY
    • 유통과학연구
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    • 제22권1호
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    • pp.61-67
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    • 2024
  • Purpose: The study has identified factors affecting dynamic capabilities and the distribution of competitive advantage under the impact of dynamic capabilities of Vietnamese fintech businesses. Research design, data, and methods: The method used in this study is a survey analysis of 120 Vietnamese fintech businesses to test the hypothesized relationships of the research model as well as evaluate its effectiveness. The study uses the Cronbach alpha analysis, factor analyses, and structural equation modeling to assess the research's measurement and structural models. Results: Research results show that 3 critical success factors: "Capacity to develop financial service ideas," "Ability to develop a platform," and "Business capacity" have a positive impact on "Dynamic capabilities." In addition, the study also evaluates the effect of "dynamic capabilities" on the "competitive advantage" of fintech businesses. Conclusion: Theoretically, this result contributes to discovering new, specific factors affecting the dynamic capabilities of fintech businesses. In practice, the research results are empirical evidence of the distribution of competitive advantages of Vietnamese Fintech businesses and their impact on dynamic capabilities.

지진-공중음파 자료를 이용한 2001년도 인공발파 식별 (Artificial blasts discrimination by using seismo-acoustic data in 2001)

  • 제일영;전명순;전정수
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2002년도 춘계 학술발표회 논문집
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    • pp.59-63
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    • 2002
  • Artificial blasts, defined as seismo-acoustic events, were discriminated from natural earthquakes in the Korean Peninsula by analyzing seismo-acoustic data. 219 seismo-acoustic events corresponding to 9 percent of total seismic events in 2001 were analyzed and classified as artificial surface blasts. Most seismo-acoustic events were concentrated in several areas. This distribution pattern was similar to the previous result in 1999-2000. Most of seismo-acoustic events especially concentrated at 7 small areas in North and South Korea. The number of seismo-acoustic events occurred in North and South Korea was 79 and 140 events, respectively. The local magnitude of seismic events from North Korea was relatively larger than from South. And some infrasound occurred from North Korea had a characteristic of sequential arrivals of signals, which reflected the different propagation in the atmosphere.

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Frequentist and Bayesian Learning Approaches to Artificial Intelligence

  • Jun, Sunghae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제16권2호
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    • pp.111-118
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    • 2016
  • Artificial intelligence (AI) is making computer systems intelligent to do right thing. The AI is used today in a variety of fields, such as journalism, medical, industry as well as entertainment. The impact of AI is becoming larger day after day. In general, the AI system has to lead the optimal decision under uncertainty. But it is difficult for the AI system can derive the best conclusion. In addition, we have a trouble to represent the intelligent capacity of AI in numeric values. Statistics has the ability to quantify the uncertainty by two approaches of frequentist and Bayesian. So in this paper, we propose a methodology of the connection between statistics and AI efficiently. We compute a fixed value for estimating the population parameter using the frequentist learning. Also we find a probability distribution to estimate the parameter of conceptual population using Bayesian learning. To show how our proposed research could be applied to practical domain, we collect the patent big data related to Apple company, and we make the AI more intelligent to understand Apple's technology.

Static Switch Controller Based on Artificial Neural Network in Micro-Grid Systems

  • Saeedimoghadam, Mojtaba;Moazzami, Majid;Nabavi, Seyed. M.H.;Dehghani, Majid
    • Journal of Electrical Engineering and Technology
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    • 제9권6호
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    • pp.1822-1831
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    • 2014
  • Micro-grid is connected to the main power grid through a static switch. One of the critical issues in micro-grids is protection which must disconnect the micro-grid from the network in short-circuit contingencies. Protective methods of micro-grid mainly follow the model of distribution system protection. This protection scheme suffers from improper operation due to the presence of single-phase loads, imbalance of three-phase loads and occurrence of power swings in micro-grid. In this paper, a new method which prevents from improper performance of static micro-grid protection is proposed. This method works based on artificial neural network (ANN) and able to differentiate short circuit from power swings by measuring impedance and the rate of impedance variations in PCC bus. This new technique provides a protective system with higher reliability.

Genotype Profiles for the Quantitative Trait Related to Milk Composition in Bulls Used for Artificial Insemination in India

  • Mukhopadhyaya, P.N.;Mehta, H.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권3호
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    • pp.326-329
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    • 2002
  • A population of exotic Holstein Friesian, Jersey, their crossbreds and the indigenous Murrah breed of buffalo bulls (n=486), used in artificial insemination breeding program were screened for the allelic distribution of the ${\kappa}$-casein and ${\beta}$-lactoglobulin genotypes. The preferred "B" allele frequency was highest in Murrah buffalo bulls followed by Jersey and Holstein Friesian. The increase in this particular allele frequency in the Holstein Friesian crossbred bulls was more when compared to their Jersey counterparts. Hardy-Weinberg's equilibrium was maintained albeit with some deviations, which was higher in crossbreds than in purebreds. The feasibility of using such large-scale molecular diagnostic tools in the field and their significance with regards to the dairy economy is discussed.

로봇 저널리즘 연구 동향 및 미래 전망 (Robot Journalism Research Trends and Future Prospects)

  • Cui, Jian-Dong;Song, Seung-keun
    • 한국정보통신학회논문지
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    • 제24권2호
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    • pp.333-336
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    • 2020
  • AI-powered robot news is drawing attention as artificial intelligence technology is fully spread in the news distribution field. Robot news still has many technical and ethical problems, but academic research on this is insufficient. This study analyzes the issue of robot writing in artificial intelligent based robot journalism industry using SWOT analysis. As a result, the advantages of big data processes, accurate information gathering, high efficiency and disadvantages such as lack of independent arguments and lack of evidence and opportunities for technical development, government support, academic development, and industrial applications, and threats such as uncritical acceptance and lack of talent have been found. This study suggests three future-oriented directions, such as human-machine collaboration, intelligent news, and chat-bot, through previous studies on the development direction of robot journalism-based article writing.