• 제목/요약/키워드: Whales

검색결과 41건 처리시간 0.024초

세일링요트의 기본적 요소와 구조에 관한 소고 (A Study on the Basic Element and Structure of Sailing-yachts)

  • 김용재
    • 수산해양교육연구
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    • 제15권1호
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    • pp.123-133
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    • 2003
  • The present investigations were carried out for the most and fundamental elements, what is called maneuverability, stability, safety, rig, sail about the world famous race, VOLVO60 and America's cup. The results obtained are summarized as follows: First, the structure of yacht should be designed with focuse on the preparation for the preparation of collision with other yachts around, with the dumps of iceberg and also whales nearby. At the same time, the accurate calculation on the each structure and equipment of yacht should be processed for the dynamic stability in the rainstorms. Second, VOLVO60, long-distance sailing, should be emphasized on the light weight and the safety, while the boat for America's cup, short-distance sailing, should be stressed on the appropriate weight of the body and the maximum speed for fast maneuverability. Third, up-to-the minute materials should be developed for the appropriate wind power and the turning of directions.

반구대 암각화와 후빙기 후기 울산만의 환경변화 (Bangudae-rockgraving-picture and environmental change in the Ulsan-Bay on the period of late-Postglatcial)

  • 윤순옥
    • 한국제4기학회지
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    • 제9권1호
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    • pp.1-18
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    • 1995
  • The intent of this study is to suppose the time of engraving of Bangudae-rockgraving-picture and the change of the ancient soci-ety related to the Postglacial transgression and regression in the Ulsan Bay. Main results can be summed up as follows; 1. It is supposed that the shoreline in the maximum Postglacial transgression of the Ulsan bay has arrived to Gulhwa-Ri about 14km upstream from the present Taehwa River mouth. 2,.This transgression has occurred about 6,000-5,000 years ago. The prehistoric men around the Bangudae had hunted the whale near the inner bay From this time the people had begun to engrave pictures on the Rock of Bangudae for the ceremony and instruction of the whale hunting,. 3. Since then the shoreline had regressed and the whale hunting area had moved to distant area from the residence and the number of the captured whales had diminished. The whale hunting society had been transformed to the overland animals on the Bangudae-rockgraving- pictures had gradually increased.

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자동기록식 수중청음기를 이용한 저주파 해양잡음의 측정 (Measurement of Low-Frequency Ocean Noise by a Self-Recording Hydrophone)

  • 김봉채;김병남;조홍상
    • Ocean and Polar Research
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    • 제29권4호
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    • pp.311-316
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    • 2007
  • Ocean noise may be used for monitoring wind speed and rainfall rate on the sea surface, as well as for tracking whales' migration routes. In particular, low-frequency ocean noise has recently been of concern with relation to the behavior of marine mammals. Low-frequency ocean noise has been increasing over the past few decades due to increase of ship traffic and offshore oil industry activities. Mechanical noise such as flow noise and cable strumming noise may be induced if low-frequency ocean noise is measured by cabled traditional hydrophone in high current areas. To successfully measure low-frequency ocean noise in a shallow water environment with strong current, we developed a self-recording hydrophone. This paper describes the main configurations of the self-recording hydrophone and presents some results on measured data.

고래자원의 가치 논쟁에 관한 연구 (A Research on the Debates of Whale Resource Values)

  • 박성쾌
    • 수산경영론집
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    • 제45권3호
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    • pp.111-129
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    • 2014
  • The main purpose of this study is to analyze the disputes concerning the 1982 moratorium on commercial whaling and the standing rights of other natural objects. Basically, the debates has arisen from the very nature of whales and other natural resources, that is to say, a mixed good of consumptive and non-use value. The debates between pro- and anti-moratorium states regarding whaling may not find out a peaceful solution without compromise or negotiation since any international institution for official settlements does not exist. If the pro-states could provide anti-states with a certain type of economic incentive which is side payments, anti-states might offer self-restraint not to whale. Here, it would be considered to apply Kaldor-Hicks compensation principles to this problem. Since 1965, some countries such as the United States and Japan began to recognize the standing right of natural objects. Even though rejected, the newt case in Korea was brought to the Supreme Court. If a standard of living increases significantly to a higher level(i.e. more than per capita income US$30,000), there would be a tendency of valuing natural objects and their beauty more and more highly.

한반도 근해 고래류의 한국어 일반명에 대한 고찰 (Review of the Korean Vernacular Names of Cetaceans)

  • 손호선;안두해;김두남
    • 한국수산과학회지
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    • 제45권5호
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    • pp.513-522
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    • 2012
  • This paper reviews the Korean vernacular names of 35 cetacean species found in Korean waters and mentioned in 19 references, including laws, high school textbooks, and books on whales. The vernacular names of 16 species were identical in all sources examined. Some names have their origins in old Korean books, while others have recently entered public awareness through movies, TV programs, and the mass media; some species are frequently studied by researchers. Given the nature of vernacular names, that is, names used by people who live in sympatry with the animals, priority was not given high consideration in this paper. Instead, we carefully investigated the origin, publicity, and rationale of the Korean common names for the 35 species. All of these Korean names are also listed in "The World Cetacea Database (http://www.marinespecies.org/cetacea/)," which contains the most accurate cetacean systematic information on the Web.

살오징어(Todarodes pacificus)와 갑오징어(Sepia esculenta)에 대한 광대역 음향산란특성의 비교 (Comparison of Broadband Acoustic Scattering Characteristics Between Japanese Flying Squid Todarodes pacificus and Golden Cuttlefish Sepia esculenta)

  • 이대재
    • 한국수산과학회지
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    • 제52권6호
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    • pp.709-718
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    • 2019
  • Cephalopods, such as the Japanese flying squid Todarodes pacificus and golden cuttlefish Sepia esculenta, are an important food source for all toothed whales, particularly bottlenose dolphins in costal and offshore waters around the Korean Peninsula. A controlled laboratory experiment was conducted to investigate the broadband acoustic backscattering from live individuals of these two cephalopod species using linear chirp signals (100-200 kHz). The backscattered echo signal was measured at about 1° intervals from -45° (head down) to +45° (head up) in the dorsal plane. The species-specific, frequency-dependent scattering characteristics were investigated by comparing the relationship between the wavelength-normalized backscattering cross-section (σ/λ2) and the wavelength-normalized fish length L/λ for each species. The estimated σ/λ2 value for Japanese flying squid was 9.51 at an L/λ range of 12.79-30.27 (mean, 21.26). This was approximately 7% of the σ/λ2 value (136.1) for golden cuttlefish at an L/λ range of 9.07-25.49 (mean, 15.77).

Small creatures can lift more than their own bodyweight and a human cannot-an explanation through structural mechanics

  • Balamonica, K;Jothi Saravanan, T.;Bharathi Priya, C.;Gopalakrishnan, N.
    • Biomaterials and Biomechanics in Bioengineering
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    • 제4권1호
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    • pp.9-20
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    • 2019
  • Living beings are formed of advanced biological and mechanical systems which exist for millions of years. It is known that various animals and insects right from small ants to huge whales have different weight carrying capacities, which is generally expressed as a ratio of their own bodyweights i.e., Strength to Bodyweight Ratio (SBR). The puzzle is that when a rhinoceros beetle (scientific name: Dynastinae) can carry 850 times its own bodyweight, why a man cannot accomplish the same feat. There are intrinsic biological and mechanical reasons related to their capacities, as per biomechanics. Yet, there are underlining principles of engineering and structural mechanics which tend to solve this puzzle. The paper attempts to give a plausible answer for this puzzle through structural mechanics and experimental modeling techniques. It is based on the fact that smaller an animal or creature, it has larger value of weight lifting by self-weight ratio. The simple example of steel prism model discussed in this paper, show that smaller the physical model size, larger is its SBR value. To normalize this, the basic length of the model need to be considered and when multiplied with SBR, a constant is arrived. Hence, the aim of the research presented is to derive this constant on a pan-living being spectrum through size/scaling effect.

한국 동해 밍크고래 Balaenoptera acutorostrata의 자원개체수 추정 (Abundance Estimates of the Minke Whale, Balaenoptera acutorostrata, in the East Sea, Korea)

  • 박겸준;안용락;김장근;최석관;문대연;박지은
    • 한국수산과학회지
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    • 제42권6호
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    • pp.642-649
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    • 2009
  • Line transect data from sighting surveys conducted in the East Sea, Korea in 2000, 2002, 2003, 2005 and 2006 were analysed to estimate densities and numbers of minke whale. The half-normal model was fit to the survey in 2000 and the uniform model was the most fitable to the survey in 2002 and 2006, and the surveys in 2003 and 2005 were fit by the hazard-rate model. The estimated density of minke whale in the survey in 2000 was estimated as 0.026 individuals/$km^2$ (CV=0.409; 95% CI 0.011-0.065) and was higher than the survey in 2002 estimated as 0.018 individuals/$km^2$ (CV=0.329; 95% CI: 0.009-0.034). The estimated density of minke whale in the survey in 2003 was estimated as 0.033 individuals/$km^2$ (95% CI: 0.008-0.139) with the highest CV 0.760. The highest density was estimated in the survey in 2005 with 0.053 individuals/$km^2$ (95% CI: 0.020-0.141). The Lowest CV (0.306) was estimated in the survey in 2006 with 0.025 individuals/$km^2$ (95% CI: 0.014-0.046). A total of 500 bootstrap samples were generated within each stratum. Density, CV and 95% CI of each surveys were increased than analytic results except the survey in 2003. There were no increasing or decreasing annual trends in the density of minke whales observed during the study period. A long-term monitor and survey is needed to assess project minke whale abundance in the East Sea.

Molecular adaptation of the CREB-Binding Protein for aquatic living in cetaceans

  • Jeong, Jae-Yeon;Chung, Ok Sung;Ko, Young-Joon;Lee, Kyeong Won;Cho, Yun Sung;Bhak, Jong;Yim, Hyung-Soon;Lee, Jung-Hyun
    • 한국해양바이오학회지
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    • 제6권2호
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    • pp.102-109
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    • 2014
  • Cetaceans (whales, dolphins, and porpoises) are aquatic mammals that experienced drastic changes during the transition from terrestrial to aquatic environment. Morphological changes include streamlined body, alterations in the face, transformation of the forelimbs into flippers, disappearance of the hindlimbs and the acquisition of flukes on the tail. For a prolonged diving, cetaceans acquired hypoxia-resistance by developing various anatomical and physiological changes. However, molecular mechanisms underlying these adaptations are still limited. CREB-binding protein (CREBBP) is a transcriptional co-activator critical for embryonic development, growth control, metabolic homeostasis and responses to hypoxia. Natural selection analysis of five cetacean CREBBPs compared with those from 15 terrestrial relatives revealed strong purifying selection, supporting the importance of its role in mammals. However, prediction for amino acid changes that elicit functional difference of CREBBP identified three cetacean specific changes localized within a region required for interaction with SRCAP and in proximal regions to KIX domain of CREBBP. Mutations in CREBBP or SRCAP are known to cause craniofacial and skeletal defects in human, and KIX domain of CREBBP serves as a docking site for transcription factors including c-Myb, an essential regulator of haematopoiesis. In these respects, our study provides interesting insights into the functional adaptation of cetacean CREBBP for aquatic lifestyle.

신경망과 LPC 계수를 이용한 고래 소리의 분류 (Classification of Whale Sounds using LPC and Neural Networks)

  • 안우진;이응재;김남규;정의필
    • 융합신호처리학회논문지
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    • 제18권2호
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    • pp.43-48
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    • 2017
  • 수중천이신호는 복잡하고 시변, 비선형 및 짧은 지속성의 특성을 지니고 있어서 기준패턴으로 모델링하기가 어렵다. 본 논문에서는 이러한 신호들을 프레임간의 중첩을 허용하는 일정한 짧은 신호로 잘라서 분석한다. 더빈 알고리듬을 이용하여 20차의 선형예측계수(LPC)를 프레임마다 추출하여 2층 은닉신경망회로의 입력신호로 사용한다. 추출된 선형예측계수들의 65%는 신경망구조의 학습에 이용되고 35%는 시험용 입력신호로 사용된다. 고래소리 분류에 사용된 고래 종류는 대왕고래, 들쇠고래, 귀신고래, 혹등고래, 밍크고래, 북방긴수염고래 등이다. 결과적으로 이러한 시험용의 신호들로부터 83%이상의 고래 소리 평균 분류율을 얻을 수 있었다.

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