• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.129-138
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• 2024

This study examines the osteological development of the Pike gudgeon, Pseudogobio esocinus in the cranial, vertebral, caudal, pelvic and pectoral girdle for the purpose of taxonomic and aquacultural studies. Adult Pike gudgeon collected from the Boseonggang River were reared at 18.5~19.5℃ (average 19.0℃). At 5 days after hatching (total length (TL) 4.25 mm), the parasphenoid, dentary, centrum of vertebrae and clavicle began to ossify. At 22 days after hatching (TL 6.33 mm), 36 to 38 vertebrae had ossified. At 42 days after hatching (TL 16.71 mm), the majority of the skeleton had ossified. Pike gudgeon exhibited comparable characteristics to other fishes of Gobionidae throughout its development, although it displayed differences in some areas, such as the caudal skeleton and fin supports.

• Korean Journal of Ichthyology
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• v.32 no.3
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• pp.160-165
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• 2020

Seasonal fluctuation in abundance and species composition of fish in coastal waters off Samcheonpo were investigated using seasonal samples collected by a beam trawl in 2019 to compare the variation of species composition and dominant species with previous studies. A total of 6,518 fish were sampled and classified into 44 species, 30 families, and 6 orders. The dominant species were Nuchequula nuchalis (1,542 individuals, 23.7%), Platycephalus indicus (529 individuals, 8.1%), Thryssa kammalensis (437 individuals, 6.7%), Argyrosomus argentatus (403 individuals, 6.2%), and Acanthogobius flavimanus (354 individuals, 5.4%). The highest number of individuals was found in July (2,385 individuals), while the lowest number of individuals was found in January (925 individuals). The diversity index was the highest in April (H'=2.733) and the lowest in July (H'=2.546).

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.688-697
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• 2014

In this study, electrode bonding technology needed for high density of rechargeable battery is studied, which is recently researched for electric vehicle, the small leisure vessel. For the alternative overcoming the limit of stacking amount able to be stacked by conventional ultrasonic welding, the low temperature bonding method, eligible for minimum of degeneration of chemical activator on the electrode surface which is generated by thermal effect as well as the increase of conductivity and tension strength caused by electrode bonding using filler metal, not using conventional direct heating on the electrode material method, is studied. Specifically to say, recently used more generally the ultrasonic welding and spot welding method are not usable for satisfying stable electric conductivity and bonding strength when much electrode is stacking bonded. If the electrical power is unreasonably increased for the welding, due to the effect of welding temperature, deformation of electrode and activating material degeneration are caused, and after the last packaging, decline of electrical output and generating heat cause to reduce stability of battery. Therefore, in this study, induction heating system bonding method using high frequency heating and differentiated electrode method using filler metal pre-treatment of hot dipping are introduced.

• Korean Journal of Ichthyology
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• v.34 no.2
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• pp.96-101
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• 2022

The egg, larvae, and juvenile development of Platycephalus indicus sampled from Yeosu estuary were conducted. The egg shape of P. indicus is spherical and transparent on the outside, with two perivitelline cavities inside and one oil globule. The diameter of the fertilized eggs were 1.03~1.12 mm (mean =1.08 mm, n =50). The embryos hatched in about 50 hrs 30 mins after fertilization at the water temperature of 20℃. The newly hatched larvae showed a total length of 2.72~3.04 mm (mean=2.93±0.21 mm, n=50). At 5 days after hatching, they were 3.88~4.42 mm (mean=4.11±0.31 mm, n=15) in TL and their yolk was completely absorbed, developing the teeth. They became juvenile 39 days after hatching and reached 10.23~11.95 mm (mean=11.09±0.86 mm, n=5) in TL. At 45 days after hatching, they were 12.01~13.25 mm (mean=12.63±0.62 mm, n=5) in TL, and their body shape and color were similar to those of adult fish.

• Journal of Korean Port Research
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• v.11 no.2
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• pp.321-337
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• 1997

Rapid change in the technological environment of marine transportation and the development of the ocean shipping industry have fostered a revolution in the port system. This in turn has caused major changes in the function and use of port in Korea. Aside from this. Mokpo Port, however continues to decline, because the existing port facilities and related subsystem are already obsolete with no chance of regaining operational effectiveness and treatment for proper implementation. Although a few studies have been done on the Mokpo Port, has not been found, any reseach for the analytical approach to the transportation system of it. This paper aims to make an extensive analysis of the physical distribution system in Mokpo Port focusing on the coordination of subsystems such as navigational aids system, quay handling and transfer system, storage system and inland transport system. The base of introduced simulation tool here is the queueing theory. The overall findings are as follows; 1. Among those vessels called at Mokpo Port in 1994, the average size of oceangoing vessels is 4,922.1 G/T, and the domestic is 317.8 G/T. The average arrival interval and service time of the domestic vessels are 6.0 hours and 24.1 hours respectively marking the berth occupation rate over 100%. Those for oceangoing vessels are 34.5 hours, 120.0 hours and 37.2%. In order to maintainin the berth occupation rate to 70% the capacity considering the 1994 of domestic piers must be extended to 145% and oceangoing vessels must be increased to 165% year called. 2. The capacity of approaching channel is enough to handle the total traffic volume. 3. Tugs are sufficiently being provided to handle all ships requiring their services 4. The capacity of storage and inland transportation systems are sufficient to handle the throughput and the yard stroage utilization rate of No.1 $\cdots$ No.5 is 4.5% and No.6 1S 30% of 1993's. 5. The utilization rate of LLc(Level Looping Crane) and PNT(PNeumaTic) are 2.7% and 18.8%, respectively. Practical solution and proposal for improvement of Transportation System in Mokpo Port are as follows; 1. To avoid the congestion in domestic pier introduction of a new port operation system is necessary allowing the domestic vessel to use the oceangoing pier. 2. To establish the port management information system to improve the efficiency of port operation. 3. To build a new storage system for high valued cargos including modernization of the present storage and handling system. 4. To insure the safety of navigation in approaching channel, The Vessel Traffic System including separation scheme is introduced. 5. To interest enormously on public relation to ship owner's association, shippers and consignees by showing that they can save cost and ship turnaround time in order to promote the call to Mokpo Port. At last, to be strategically change the function of Mokpo Port to the Leisure, Fishing & Ferry as well as Maritime port.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.83-90
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• 2023

Five days after hatching in Konosirus punctatus, the larvae were 5.86~6.21 mm (mean 5.96 mm) in TL and ossified parasphenoid, prefrontal, premaxillary, dentary. Sixteen days after hatching, the larvae were 9.66~10.18 mm (mean 9.96 mm) in TL and ossified prootic, opisthotic, ectopterygoid, and epihyal. Twenty-five days after hatching, the larvae were 11.02~12.64 mm (mean 11.03 mm) in TL and ossified supraclavicle, posttemporal, four actinost. Twenty-eight days after hatching, the larvae were 11.98~12.81 mm (mean 12.34 mm) in TL and ossified frontal, pterotic, epiotic, exoccipital, basioccipital, preorbital, maxillary, hyomadibular, preopercle, opercle, hypohyal. Thirty-six days after hatching, the larvae were 15.26~16.39 mm (mean 16.11 mm) in TL and ossified scapula. 37 days after hatching, the larvae were 15.33~16.87 mm (mean 16.25 mm) in TL and ossified ethmoid, nasal, parietal, supraoccipital, and suborbital. Forty-five days after hatching, the larvae were 20.01~21.83 mm (mean 21.14 mm) in TL, and the shoulder girdle was completed by coracoid formation. Forty-eight days after hatching, the larvae were 22.46~24.03 mm (mean 23.20 mm) in TL and ossified articular and subopercle. When the juvenile reached 27.11~34.09 mm (mean 30.11 mm) in TL (53 days after hatching) completed ossification of the cranium, vertebrae, pelvic girdle, shoulder girdle, caudal bone, and pterygiophore.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.30-39
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• 2024

This study examines the osteological development of the Bartail Flathead Platycephalus indicus in the cranial, vertebral, caudal bones and pelvic, sholder grilde bones for the purpose of taxonomic studies. Adult P. indicus were collected from the Yeosu coast and artificially fertilized. Juveniles were reared at 18.5~21.8℃ (average 20.0℃±0.5℃). At 3 days after hatching (total length (TL) 3.49±0.32 mm), the parasphenoid and clavicle began to ossify. At 14 days after hatching (6.34±0.24 mm), the parietal and exoccipital bones of the cranium, the six branchiostegal rays of the hyoid, the urostyle of the caudal bones and the actinost of the shoulder girdle had ossified. At 39 days after hatching (11.39±0.86 mm), the preorbital and suborbital bones of the cranium were ossified, ossification of the pelvis girdle had begun, and the sholuder girdle was fully ossified. The number of vertebral columns were 26. At 45 days after hatching (12.63±0.62 mm), the nasal and supraorbital bones were ossified and the entire skeleton of the juvenile was completely ossified.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.174-181
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• 2024

This study examines the community characteristics of fish species collected by fyke net from the eastern coastal waters of Yeosu, Korea, during the period from 2020 to 2021. A total of 4,539 fish were sampled and classified into 43 species, 28 families, and 7 orders. The dominant species included Mugil cephalus (14.4%), Konosirus punctatus (10.9%), Lateolabrax japonicus (8.3%), Acanthopagrus schlegelii (7.9%), and Pennahia argentata (7.2%). The diversity index was highest in October (H'=2.888) and lowest in February (H'=2.075). Furthermore, the dominance index was highest in March (DI=0.524) and lowest in December (DI=0.178). Hierarchical cluster analysis (HCA) revealed that fish communities could be divided into three groups based on Bray-Curtis similarity. Group 1, consisting mainly of species collected from June to October, formed one cluster. Group 2, including winter spawning species such as Pseudopleuronectes yokohamae, Clupea pallasii, and Hexagrammos otakii, sampled from November to February, formed another cluster. Group 3, which included species such as Larimichthys polyactis, Amblychaeturichthys hexanema, and Sebastes inermis, formed a cluster collected from March to May. The eastern coast of Yeosu is considered a suitable habitat for fisheries resources, including highly economically valuable species, and it is also assumed to be an important spawning and nursery ground for many fish species.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.20-29
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• 2024

Hemitripterus villosus, a promising aquaculture fish species, is facing declining stocks. This study aims to provide normative standards for skeletal development to address persistent skeletal deformities in farmed fish. Specimens utilized in the study underwent artificial insemination with captured fish, and the resulting larvae and fry were preserved in a formalin solution. The skeletal ossification process commenced immediately after hatching, affecting the parasphenoid, premaxillary, maxillary, and dentary structures at an average total length of 13.65±0.71 mm (n=5). By sixty-five days post-hatching, ossification extended to the ethmoid and supraorbital, completing the head's development at an average total length of 21.24±0.50 mm (n=5). Clavicle ossification occurred at seven days post-hatching, corresponding to an average total length of 14.61±0.52 mm (n=5). At forty-four days post-hatching, the ossification of 4 actinosts took place, completing the shoulder girdle, with an average total length of 18.15±0.61 mm (n=5). Vertebral ossification initiated at ten days post-hatching, with an average total length of 14.80±0.65 mm (n=5). By fifty-four days post-hatching, 39 vertebral columns were ossified, reaching an average total length of 18.67±0.54 mm (n=5). Vertebral development was complete at sixty days post-hatching, with an average total length of 20.25±0.45 mm (n=5). This study sheds light on the skeletal development of H. villosus, providing valuable standards and fundamental data for understanding skeletal deformities in this species.

• Journal of the Korean association of regional geographers
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• v.2 no.2
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• pp.133-157
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• 1996

Recently, international convention competition has greatly expanded with the globalization and expand of world economy. As the conventions market has grown, so have the number of places and facilities of convention competing for business, and numerous trade show and the related meetings held the several cities toward world city such as the United States, Europeans Countries, Japan, and Singapore. Convention, in general, are defined as an assembly, often periodical, of members or delegates, as a political, social, professional or religious group. Convention center means the place that hold several social, political, economic conferences and meetings, trade show, exhibitions, and events. Convention center are consisted the several facilities such as meeting room, exhibition hall, event hall. Historically, meetings, conventions, and trade show have been serviced primarily by hotel and convention centers. With the expand of world trade and flow in recent, the conventions, expositions, and meetings industry (CEMI), however, is one of the most rapidly growing industries in hospitality and tourism, and CEMI provides import effect on regional economy and regional development including regional tourism industry. This study focuses on the establishment strategies and location analysis of convention center as a agent for regional development in a case of Yosu Peninsular Area (YPA). YPA is one of the major industrial area of our country, and displays the rapid regional urbanization and social change with the construction such as Kwangyang container port facilities, Yulchon industrial complex, and the extension planning of industrial estate related to Kwangyang Iron and Steel Company, and population size of this area will be reached about two million peoples in 2011. This area, particularly, will be functioned as a major container & export port of our country after the completion of Kwangyang container port facilities in 1988. If the planned industrial estate is constructed, the convention center for conference exhibition, information exchange, and resort facilities for exhibition, international communication will be needed. In addition, resort and leisure facilities for conventions' participants need. This area, therefore, has to make the establishment of convention center for regional development in future. Thus, the major strategies and idea for establishment of convention center as follows: first, this area has requirements for resort convention center, because this area will be functioned as a major export port and industrial district in 21 century; second, in the location analysis of convention center site, Sinwol & Woongchon district, Soho district, and Yongju & Hodu district are selected as developing possible sites; third, the convention center of this area has to consist of two functions such as convention facilities and marine resort facilities; fourth, in order to establish convention center, the selection of main group, financial raising strategies, and the organization of propulsion committee for establishment of convention center are required.