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Characteristics of Linoleic Acid Production by Marine Fungi in Sea Water Media (해수배지를 이용한 해양 미생물의 Linoleic acid 생성 특성 규명)

  • 김수정;박경원;허병기
    • KSBB Journal
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    • v.15 no.2
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    • pp.195-200
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    • 2000
  • Studies were made on the optimization of media to c비tivate Thraustochytrium aureum A TCC 34304 for the enhanc엉d p production of linoleic acid. The medium optimization was made with the artificial sea water medium. Yeast extract, sodium g glutamate, peptone and tryptone were considered as nitrogen source. The effect of $\infty$ncentration of nitrogen source as well a as initial glucose on the production of linoleic acid were investigated to optimize the media. The maximum yield of lipid was 0 0.302 mg/g cell mass when initial glucose $\infty$ncentration was 10 g/L and sodium glutamate was used as nitrogen source, a and the yield of linoleic acid to unit cell mass was also maximum to be 8 % in that case. The highest linoleic acid c concentration was obtained in the initial glucose concentration 30 g/L regardless of the kinds of nitrogen source and the | linoleic acid concentration was 0.208 g/L when peptone was supplemented to be 2 g/L.

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A Study on Indicator Bacteria for Water Quality Management of Urban Artificial Lakes (도심지역 인공호의 수질관리를 위한 지표세균에 관한 연구)

  • Chu, Duk-Sung;Kwon, Hyuk-Ku;Lee, Sang-Eun;Lee, Jang-Hoon
    • Journal of Environmental Health Sciences
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    • v.33 no.4
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    • pp.299-305
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    • 2007
  • Distribution of fecal pollution indicator bacteria and environmental parameter were investigated of urban artificial lakes. An average concentration of temperature, pH, SS, DO, $COD_{Mn}$, T-P, T-N, Turbidity, Chl-a were $21.5^{\circ}C$, 8.07, 116.70 mg/l, 8.66 mg/l, 2.24 mg/1, 0.52 mg/l, 1.71mg/l, 80.54 NTU, and 52.12 mg/l respectively. From the results of bivariate correlation analysis, fecal contamination indicator bacteria were found to be mutually correlated. And turbidity and suspended solid were correlated. From the results of principal component analysis, four factors were extracted. And four factors of variance explained up to 81.5 percentage. Factor 1 was pollution pattern by fecal contamination, factor 2 was physical pollution pattern by pollution source, factor 3 was natural pollution by precipitation, and factor 4 was artificial pollution pattern by organism.

Artificial Habitat Creation of Luciola lateralis (Coleoptera: Lamphyridae) and Research of Breeding Technique for Festival at Hwadamsup, Korea

  • Kang, Seung-Ho;Jeon, Mi-Kyung;Kwon, Soon-Jik;Na, Seok-Jong;Kim, Kyung-Ho;Jeong, Jong-Chul
    • Journal of Forest and Environmental Science
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    • v.34 no.4
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    • pp.275-283
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    • 2018
  • This study created the running water (Bandibooliwon) and lentic water (Sooryunwon) artificial habitats of Luciola lateralis in Hwadamsup, Gwangju-si, Gyunggi-do from April 2014 to February 2016. Through various habitat types, metapopulation was formed, and more sound population was induced to be maintained via interactions between habitats. We investigated coenosite at the habitat creation-target site, and 20 species in the lentic water site and 38 species in running water site were found. After releasing L. lateralis, we checked the status of settlement of L. lateralis larvae through traps and macroscopy, controlled the flow velocity of the habitats in line with the life cycle of L. lateralis (hatching, larva period, landing, pupation, copulation, and oviposition), and shaped gentle slope at water side, and planted moss. We artificially supplied melanian snails (Semisulcospira sp.), the food source, in the running water site and induced stable feeding. Also, We created artificial insectary, bred larvae stably in winter, and secured firefly population for a festival. Through night time observation, the time most suitable for a festival was confirmed to be from 20:30 to 22:00.

Autonomous-Driving Vehicle Learning Environments using Unity Real-time Engine and End-to-End CNN Approach (유니티 실시간 엔진과 End-to-End CNN 접근법을 이용한 자율주행차 학습환경)

  • Hossain, Sabir;Lee, Deok-Jin
    • The Journal of Korea Robotics Society
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    • v.14 no.2
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    • pp.122-130
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    • 2019
  • Collecting a rich but meaningful training data plays a key role in machine learning and deep learning researches for a self-driving vehicle. This paper introduces a detailed overview of existing open-source simulators which could be used for training self-driving vehicles. After reviewing the simulators, we propose a new effective approach to make a synthetic autonomous vehicle simulation platform suitable for learning and training artificial intelligence algorithms. Specially, we develop a synthetic simulator with various realistic situations and weather conditions which make the autonomous shuttle to learn more realistic situations and handle some unexpected events. The virtual environment is the mimics of the activity of a genuine shuttle vehicle on a physical world. Instead of doing the whole experiment of training in the real physical world, scenarios in 3D virtual worlds are made to calculate the parameters and training the model. From the simulator, the user can obtain data for the various situation and utilize it for the training purpose. Flexible options are available to choose sensors, monitor the output and implement any autonomous driving algorithm. Finally, we verify the effectiveness of the developed simulator by implementing an end-to-end CNN algorithm for training a self-driving shuttle.

Digital Image Comparisons for Investigating Aging Effects and Artificial Modifications Using Image Analysis Software

  • Yoo, Yeongsik;Yoo, Woo Sik
    • Journal of Conservation Science
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    • v.37 no.1
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    • pp.1-12
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    • 2021
  • In the digital era, large archives of information and Internet accessibility make information search, including image search, easier and affordable, even from remote locations. Information transmission and sharing can be performed instantly, at any moment. In the case of images, there are risks of transmitting and recklessly sharing intentionally modified images. Such modified images can also be transmitted and used as an additional source of information by followers. In this study, historical portraits of Yu Kil-Chun are shown, who was the first Korean student to study in both Japan and the United States. He was an intellectual, writer, politician, and independence activist of Korea's late Joseon Dynasty. Using image processing software, the portrait images were compared to investigate aging effects and artificial modifications. Statistics of red (R), green (G), blue (B), and L*, a*, and b* values of every pixel in the selected identical areas of the portraits were compared to identify possible causes of variations, including aging effects and artificial modifications. Sepia toning, used in black and white photographs until the 1930s, and modern digital sepia toning can be very confusing owing to their aging effects. The importance of preservation of physical copies and preservation of context (interconnections between data and between documents) is discussed from archiving and conservation science perspectives.

A lightweight true random number generator using beta radiation for IoT applications

  • Park, Kyunghwan;Park, Seongmo;Choi, Byoung Gun;Kang, Taewook;Kim, Jongbum;Kim, Young-Hee;Jin, Hong-Zhou
    • ETRI Journal
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    • v.42 no.6
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    • pp.951-964
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    • 2020
  • This paper presents a lightweight true random number generator (TRNG) using beta radiation that is useful for Internet of Things (IoT) security. In general, a random number generator (RNG) is required for all secure communication devices because random numbers are needed to generate encryption keys. Most RNGs are computer algorithms and use physical noise as their seed. However, it is difficult to obtain physical noise in small IoT devices. Since IoT security functions are required in almost all countries, IoT devices must be equipped with security algorithms that can pass the cryptographic module validation programs of each country. In this regard, it is very cumbersome to embed security algorithms, random number generation algorithms, and even physical noise sources in small IoT devices. Therefore, this paper introduces a lightweight TRNG comprising a thin-film beta-radiation source and integrated circuits (ICs). Although the ICs are currently being designed, the IC design was functionally verified at the board level. Our random numbers are output from a verification board and tested according to National Institute of Standards and Technology standards.