• Title/Summary/Keyword: dolphin

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Histological Features of the Testis in the Long-beaked Common Dolphin from Korean Waters

  • Kim, Juhwan;Jang, Sungwoong;Jeon, Yubyeol;An, Du Hae;Kim, Doo Nam;Hyun, Sang-Hwan;Moon, Changjong
    • Journal of Embryo Transfer
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    • v.28 no.1
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    • pp.73-78
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    • 2013
  • The present study examined the histological characteristics of adult testis in the long-beaked common dolphin (Delphinus capensis) from Korean waters and the localization of DEAD-box polypeptide 4 (DDX4; a germ cell marker) and vimentin (a Sertoli cell marker) expression in the dolphin testis compared with that in terrestrial mammals, including dogs and rats. The seminiferous tubules of dolphin testis have very small or completely closed lumens, and spermatogenic cells and Sertoli cells within the tubules cannot be differentiated. Immunohistochemical analysis showed that, in the dolphin testis, DDX4- and vimentin-positive cells were scattered extensively within the tubule, whereas in the dog and rat testis, DDX4 immunoreactivity was localized in spermatogenic cells of the adluminal compartment, and vimentin immunoreactivity was localized in Sertoli cells of the basal compartment in the seminiferous epithelium. These results suggest that the histological characteristics of the seminiferous tubules in the dolphin testis differ from those of terrestrial species.

Distribution Status of Indo-Pacific Bottlenose Dolphin Tursiops aduncus in the Jeju Island Based on Social Media Data (소셜 미디어 정보를 활용한 제주도 남방큰돌고래(Tursiops aduncus)의 분포 현황 파악)

  • Kim, Hyun Woo;Lee, Dasom;Sohn, Hawsun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.51 no.5
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    • pp.600-605
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    • 2018
  • The Indo-Pacific bottlenose dolphins Tursiops aduncus are the only cetacean species that can be observed visually on coastal areas of Jeju Island and regarded as one of valuable tour resources. We attempted to figure out location and timing information of the dolphin sightings collected from two major social media, Naver $Caf{\acute{e}}$ and Instagram. 142 of dolphin sighting information were derived from 2,501 dolphin related postings on Naver $Caf{\acute{e}}$ between 2004 to 2017. 292 informative postings also were found on Instagram through hashtag searching. The number of posts about dolphin sighting was not frequent until 2014. Since 13 posts were found in 2014, dramatic increase of the sighting numbers was accelerated as 38 in 2015, 93 in 2016 and 269 in 2017. 195 (45.7%) from coastal area of Daejeong-eup, south-western part of the Island, were posted. The number of dolphin sightings also high from Gujwa-eup(n=50, 11.7%), Hangyeong-myeon (n=49, 11.5%), Seongsan-eup (n=38, 8.9%) and Seogwipo-si (n=34, 8.0%). Our results show that social media data has a high potential to be used as a data source for study of distribution pattern of the dolphins.

Design Conditions for Dolphin Berth by Tanker Fleet Analysis

  • Kang, Seok-Jin;Lee, Joong-Woo;Lee, Dong-Hyun;Kim, Hee-Jae
    • Journal of Navigation and Port Research
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    • v.37 no.6
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    • pp.647-653
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    • 2013
  • Energy acquisition due to the increase of oil price is one of the most important issues and policy for most countries. Various tankers have been built in the world and sent to the trade market. It is necessary to build the port infrastructure and facilities to give them proper services such as mooring, packing, storing, and transshipment, etc. However, the domestic guidelines or standards for design and construction for the dolphin berth among these facilities are out of date and do not meet the recent trend of tanker types. Therefore, it requires amendment on the guidelines or standards. In this study, a detailed analysis of the tanker fleet, covering 8,000 ships under operation and order to build, is made to estimate the proper PBL(Parallel Body Length) of each tanker class. After discussion and comparison on the dolphin berth design and construction codes of various countries, those are the leading countries of tanker operation and management, suggestion was made to amend on the design code. The referred codes are of Korea, Japan, UK, USA, and Canada. The analysis of tanker fleet shows the PBL as 0.45L under the normal ballast condition. In order to verify the deduced amendment on the domestic design code for dolphin berth, it was selected one of the domestic dolphin berth, located at the Yeosu oil terminal, which is almost completed to construct. The design criteria and expected tankers to moor in that terminal were analyzed and the appropriateness and countermeasure for deficiency were summarized.

Characteristics of Bottlenose Dolphin(Tursiops truncatus) Whistle (큰돌고래의 휘슬음 특성)

  • 신형일;서두옥;이대재;황두진;배문기;이유원
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.4
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    • pp.271-277
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    • 2002
  • This paper was described on the characteristics of bottlenose dolphin (Tursiops truncatus) whistle to develop a warning and attracting acoustic system which can be made friends woith environment and minimized to the fishing pollution from Cetaceans. The experiment for the acoustics of bottlenose dolphin whistle was carried out in dolphin performance hall at Seoul Grand Park during 18th~19th April, 2002. The frequency and the spectrum level of whistle a same pool were revealed 6~10KHz and 85㏈ but those revealed two harmonic waves a 6.7KHz and 21.3KHz for the frequency and 110㏈ and 94㏈ for the spectrum level, respectively, when a dolphin isolated from others. The range of frequency change of whistle was 3.86KHz and continuous time was 0.08 sec. The range of frequency change 10.20 KHz higher as 14.06 KHz and continuous time was 0.11sec longer as 0.19sec when a dolphin isolated from others. By the Mann-Whitney test for the result, there was a significant difference for the range of frequency change and continuous time between normal condition and when a dolphin was isolated from others. The pattern of whistle at the dolphin performance hall was five types and the frequency was getting increased slowly in the range of 5~10KHz at normal condition but there were pattern change of 5~20KHz at the isolated condition. Therefore it is thought that these experiments would be valuable for the development of acoustic system.

COMPARISONS OF MEASUREMENTS OBTAINED FROM LATERAL CEPHALOMETRIC RADIOGRAPHS AND DIGIGRAPHS OF DOLPHIN IMAGING SYSTEM (측모 두부 방사선사진과 컴퓨터 영상사진 (Dolphin Imaging System)의 계측치 에 관한 비교)

  • Park, Hae-Joon;Park, Young-Chel
    • The korean journal of orthodontics
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    • v.24 no.3 s.46
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    • pp.521-534
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    • 1994
  • The purpose of this study was to compare the differences in measurements between cephalometric radiographs and digigraphs of Dolphin Imaging System. 26 Korean adult male and 24 adult female with normal occlusion were selected. For each subject lateral cephalogram was taken. Digitizing with Digigraph Work Station of Dolphin in System. was performed as well. 50 tracings and 50 digigraphs were analyzed with Yonsei, Ricketts, Burstone analyses. The comparable measurements between tracing group and digigraph group were statistically analyzed. The results were as follows: 1. 13 of 64 comparable measurements did not show any statistically significant difference (P>0.05) between tracing group and digigraph group. 2. Three of the measurements with FH plane as a reference plane did not show any statistically insignificant difference. All measurement with SN plane as a reference plane showed statistically significant difference(p<0.05). 3. The measurements which showhed no statistically significant difference were mostly short distance linear measurements while most of the angular measurements showed statistically significant difference(p<0.05).

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Feasibility of Photo-identification Techniques for the Bottlenose Dolphins(Tursiops truncatus) from Jeju Island, Korea

  • Song, Kyung-Jun;Kim, Zang-Geun;An, Yong-Rock;Choi, Seok-Gwan;Sohn, Haw-Sun;Zhang, Chang-Ik
    • Fisheries and Aquatic Sciences
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    • v.11 no.3
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    • pp.166-171
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    • 2008
  • The feasibility of photo-identification techniques for the bottlenose dolphins from Jeju Island, Korea, and the potential for dolphin watching were simultaneously evaluated in this study. During the sighting survey, a pod of bottlenose dolphins composed of approximately 30 individuals was observed in the southwestern coastal area of Jeju Island. Among 35 suitable photographs, five bottlenose dolphin individuals were identified and cataloged using unique nicks and notches on their dorsal fins. This shows that the Jeju Island dolphins can be individually identified by the nicks and notches on their dorsal fins using photo-identification techniques. Furthermore, the Jeju Island population appears to be suitable for long-term population biology studies using this technique. The potential for dolphin watching around the island would be higher if more information on the seasonal distribution, movement, and residency of this population were obtained.

A Study on the Design of Dolphin System for VLFS (부유식 해양구조물을 위한 돌핀 계류시스템의 설계 연구)

  • Cho Kyo-Nam
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.19 no.1 s.71
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    • pp.105-111
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    • 2006
  • Dolphin mooring system can be a good candidate for the VLFS fastening system in view point of strength and effectiveness. In the design process of the dolphin system, precise calculation of the wave forces and the subsequent selecting the proper number of the piles adopted are one of the main factors. In this paper, one of the design process of the dolphin system is investigated and a proper configuration of the system is derived based on the structural characteristics of the system that was obtained through the structural analysis of the basic pile element confronted to the external loadings including wave impact load. It was found that lot the better design of ihe mooring system for VLFS, mono pile mooring system is more recommendable in a specific condition than other multi piles mooring system.

Optimum design of steel frame structures by a modified dolphin echolocation algorithm

  • Gholizadeh, Saeed;Poorhoseini, Hamed
    • Structural Engineering and Mechanics
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    • v.55 no.3
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    • pp.535-554
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    • 2015
  • Dolphin echolocation (DE) optimization algorithm is a recently developed meta-heuristic in which echolocation behavior of Dolphins is utilized for seeking a design space. The computational performance of meta-heuristic algorithms is highly dependent to its internal parameters. But the computational time of adjusting these parameters is usually extensive. The DE is an efficient optimization algorithm as it includes few internal parameters compared with other meta-heuristics. In the present paper a modified Dolphin echolocation (MDE) algorithm is proposed for optimization of steel frame structures. In the MDE the step locations are determined using one-dimensional chaotic maps and this improves the convergence behavior of the algorithm. The effectiveness of the proposed MDE algorithm is illustrated in three benchmark steel frame optimization test examples. Results demonstrate the efficiency of the proposed MDE algorithm in finding better solutions compared to standard DE and other existing algorithms.

Motion Analyses for a Very Large Floating Structure with Dolphin Mooring Systems in Irregular Waves (불규칙파 중에서 돌핀 계류된 해상공항에 대한 운동 해석)

  • 이호영;신현경;임춘규;강점문;윤명철
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.57-62
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    • 2000
  • The very large flcating structure which am be used for as airport may be as large as several kilomet wide. The first order wave forces as well as wave drift forces are very important forces on such a very large floating In the present studv, the time simulation of motion responses with dolphin-moored VLFS in waves is presented The coeffcients and wave forces involved in the equations are obtained from a three-dimensionul panel method in the frequc The horizontal drift forces and mooring forces for dolphin systems are taken into account. As for numerical example, analyses are carried out for a VLFS in irregular wave condition

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Pulmonary Botryomycosis in a Gill`s bottle-nosed Dolphin (태평양돌고래에서 폐장의 포도상 진균증)

  • 강민수;최재훈;오상연;한인규;김대용
    • Journal of Veterinary Clinics
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    • v.19 no.2
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    • pp.250-252
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    • 2002
  • A 14-year-old female Gill's bottle-nosed dolphin died after having 1 month history of depression, anorexia, and respiratory insufficiency. At necropsy, numerous well-demarcated tan firm nodules in variable sizes ranging from 2 m to 3 cm in diameter were scattered throughout the lung lobes. Histologically, the pulmonary nodules formed typical granulomatous inflammation. Center of the granulomatous foci consisted of necrotic center with gram positive cocci surrounded by eosinophilic Splendore-Hoeppli material then by macrophages, epithelioid cells, multinucleated giant cells, a few lymphocytes and fibroblasts. The is the first report of pulmonary botryomycosis in dolphin in Korea.