• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.525-526
• /
• 2014

Currently many people are concerned about 'Amusement With Prize(AWP)', together with the starting of Game Rating and Administration Committee (hereafter 'GRAC'). The mature-rated arcade games reproduced in reel game like the sea story in addition to main game and sub-game, causing social confusion in 2006, are waited for the reviewing of 'GRAC'. Although the game is reproduced in poker style as game system, in reel method as game graphic like 'AWP', the Supreme Court's decision is considered as a poker game May 23, 2013 in the past. Moreover, the Supreme Court said that it is not illegal because they decide that game users do not make a great loss in their possessions, without money change. The research tries to find the direction of the reviewing the mature-rated arcade game for guarantee of objectivity and reliability.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.52 no.5
• /
• pp.524-533
• /
• 2019

Sea urchins are hugely destructive of marine forest ecosystems. This study aimed to determine the behavioral response of purple sea Urchins Heliocodaris crassispina to food and an electrical stimulus and to investigate the attraction radius of these stimuli, with an eye to the development of technology for controlling sea urchin numbers. Ten purple sea urchins, housed in circular acrylic tank, were tested against various attractant stimuli. In addition, an experiment was conducted with 200 purple sea urchins in a large water tank to observe movement patterns and the attractiveness of various stimuli. In the smaller experiment, eight out of 10 sea urchins were attracted to food, and these attractive effects were maintained in all except one of the affected urchins. However, the attractant effects of the electrical stimulus were maintained in only three sea urchins. The results of the larger experiment indicated that differences in the attractant power of food and an electrical stimulus were 54%-78%, and approximately 5-15% of sea urchins were attracted by the electrical stimulus.

• Journal of Digital Convergence
• /
• v.19 no.6
• /
• pp.323-329
• /
• 2021

Based on the research of the Public Welfare Games 'Mountaineering LightsUp', which is the main theme of helping the disadvantaged in society, this study uses the questionnaire method to obtain user data, and collects the data by using AMOS analysis for the effect of game interest elements on the experience of players. The results showed that the interesting elements (goal, obstacles, sense of belonging, atmosphere, story, information, and player to player communication) of the game were positively influenced by the experience of the game. And the questionnaire showed that the game still had problems such as playing simple, difficulty, lack of popularity, lack of feedback, and lack of storytelling. This paper also puts forward some proposals for these deficiencies. In future research, the research sample will be expanded, the research content will be improved, and the future Public Welfare Games will be designed and developed.

• Journal of Biomedical Engineering Research
• /
• v.45 no.1
• /
• pp.20-25
• /
• 2024

Extracellular vesicles (EVs) are nano-sized lipid bilayer vesicles released by cells. EVs act as messengers for cell-to-cell communication. Inside, it contains various substances that show biological activity, such as proteins, lipids, nucleic acids, and metabolites. The study of EVs extracted from terrestrial organisms and stem cells on inflammatory environments and tissue regeneration have been actively conducted. However, marine organisms-derived EVs are limited. Therefore, we have extracted EVs from sea urchins belonging to the Echinoderm group with their excellent regenerative ability. First, we extracted extracellular matrix (ECM) from sea urchin gonads treated with hypotonic buffer, followed by collagenase treatment, and filtration to collect ECM-bounded EVs. The size of sea urchin gonad-derived EVs (UGEVs) is about 20-100 nm and has a round shape. The protein content was higher after EVs burst than before, which is evidence that proteins are contained inside. In addition, proteins of various sizes are distributed inside. PKH-26 was combined with UGEVs, which means that UGEVs have a lipid membrane. PHK-26-labeled UGEVs were successfully uptaken by cells. UGEVs can be confirmed to have the same characteristics as traditional EVs. Finally, it was confirmed that Schwann cells were not toxic by increasing proliferation after treatment.

• Korean Journal of Environmental Biology
• /
• v.38 no.2
• /
• pp.207-215
• /
• 2020

Toxic assessment of antifouling agents (diuron and irgarol) was conducted using the fertilization and the normal embryogenesis rates of the sea urchin, Mesocentrotus nudus. Bioassessment began with male and female reproductive cell induction. White or cream-colored male gametes(sperm) and yellow or orange-colored female gametes (eggs) were acquired and fully washed, separately. Then, the fertilization and normal embryogenesis rates were measured after 10 min and 48 h of exposure to the toxicants, respectively. The fertilization and embryo development rates were greater than 90% in the control, validating the suitability of both endpoints. The normal embryogenesis rates were significantly decreased with increasing concentrations of diuron and irgarol, but no changes in the fertilization rates were observed in concentrations ranging from 0 to 40 mg L^-1. The EC₅₀ values of diuron and irgarol for the normal embryogenesis rates were 20.07 mg L^-1 and 22.45 mg L^-1, respectively. The no observed effect concentrations (NOEC) were <1.25 mg L^-1 and the lowest observed effect concentrations (LOEC) were 1.25 mg L^-1 and 2.5 mg L^-1, respectively. From these results, concentrations of diuron and irgarol over 1.25 mg L^-1 and 2.5 mg L^-1, respectively, can be considered to have toxic effects on invertebrates, including M. nudus. The ecotoxicological bioassay in this study using the noted fertilization and normal embryogenesis rates of M. nudus can be used as baseline data for the continued establishment of environmental quality standards for the effects of antifouling agents(especially diuron and irgarol) in a marine environment.

• Korean Journal of Environmental Biology
• /
• v.38 no.4
• /
• pp.518-527
• /
• 2020

The aim of this study was to define the toxic effects of diuron and irgarol, which are new-antifouling agents, on the fertilization rate and normal embryogenesis rate in the sea urchin, Hemicentrotus pulcherrimus. In addition, the study was intended to confirm the hindrance of development in sea urchins. The fertilization rate of H. pulcherrimus was not decreased by the tested concentrations. However, the normal embryogenesis rate was decreased in a concentration-dependent manner. The 50% effective concentrations (EC₅₀) of normal embryogenesis rate were 7.12 mg L^-1 and 2.31 mg L^-1, respectively. As the embryos developed into pluteus larvae, after 18 h of exposure to diuron and irgarol at EC₅₀, development of the early gastrula stage was delayed, and significant developmental delays were observed after 24 h. After this, continuous developmental delays were observed in the process leading to the early gastrular, gastrular, early pluteus, and pluteus stages. Therefore, the toxic effects of diuron and irgarol on sea urchins were attributed to the delay in the developmental processes in the early life stages. Diuron and irgarol are highly persistent in the environment and have known-well toxic effects on various marine organisms including invertebrates, as shown in this study. Therefore, it is urgent to establish an environmental protection strategy to prevent the pollution of and preserve the marine environment.

• Korean Journal of Environment and Ecology
• /
• v.30 no.6
• /
• pp.996-1008
• /
• 2016

Effects of substrate types (bedrock and boulder habitat) on the community structures of benthic biota (macroalgae, macrobenthos) were monthly examined at Sinheung in Jeju Island, Korea, from Feb. to Nov. 2015. Species diversity of seaweeds and macrobenthos was greater at bedrock sites with 57 and 102 species than at boulder sites having 42 seaweeds and 67 macrobenthos. Average annual biomass of seaweeds was $1,601.13g\;wet\;wt./m^2$ at bedrock site and $448.85g\;wet\;wt./m^2$ at boulder site. Ecklonia cava was the most dominant species, occupying 62.64% ($1,002.93g/m^2$)of total biomass at bedrock. Amphiroa anceps was the most dominant species and subdominant species was Ecklonia cava, Grateloupia angusta, Peyssonnelia capensis and Meristotheca papulosa at boulder site. Density and biomass of macrobenthos were estimated to be $106.9indivi./m^2$ and $871.93g/m^2$, respectively at bedrock site and they were $64.6indivi./m^2$ and $984.28g/m^2$ at boulder site. The dominant macrobenthos species based on biomass were Turbo comutus (36.40%), Astralium haematragum (19.18%) and Anthocidaria crassispina (13.61%) at bedrock site and they were Alveopora japonica (54.13%) and Psammocora profundacella (24.28%) at boulder site.

• Journal of Mushroom
• /
• v.8 no.3
• /
• pp.96-101
• /
• 2010

The purpose of this study was to evaluate the mineral difference about Phellinus from cultivated on mulberry, oak and elm by ICP test. The major mineral components were Ca, K, Fe, P, Al and Na. In Ca, fruiting bodies from cultivated on mulberry were shown about 2~4 times highest, and in case of K was fruiting bodies from cultivated on oak shown about 2 times highest as against the other sample groups. Especially, Na was fruiting bodies from cultivated on oak shown about 10 times highest as against the other sample groups. In this study, fruiting bodies on P. linteus and P. baumii from cultivated the same kind of material lumber are similar mineral components, and we can't really find much their difference. As a results, what kind of mineral component content had showed depend on material lumber.

• The Korean Journal of Malacology
• /
• v.27 no.3
• /
• pp.229-246
• /
• 2011

This study was performed to know and compare the community structures of macrobenthic invertebrates of eight fishing grounds in the coastal waters of Jeju Island from September to October 2008. A total of 166 species was identified. Mollusks comprised 77 species (46.4%); Arthropods 24 (14.5%), Cnidarians 18 (10.8%); Poriferans 16 (9.6%); and the others including Echinoderms 33 (17.7%). Density and biomass were estimated to be 6,905 ind./$m^2$ and 113,100.7 gwwt/$m^2$, respectively. Gastropods was the most dominant taxon in terms of abundance (3,311 ind./$m^2$) and number of species as well, and Gastropods was predominant in biomass (55,789.2 gwwt/$m^2$). The dominant species were Omphalius pfeifferi, Astralium haematragum, Turbo cornutus, Ergalatax contraacta, Lithophaga cura, Anthocidaris crassispina, Herdmania monus in 5-15 m. Based on the cluster analysis, the study area could be divided into two station groups. The biodiversity, evenness and richness index appeared as follows: H' = 1.59-2.95, E' = 0.38-0.87, R = 3.3-10.4. The dominance index were highest in Daepo and lowest in Woljeong.

• Journal of Aquaculture
• /
• v.3 no.1
• /
• pp.89-125
• /
• 1990

In order to improve top shell seed production techniques spawning and larvae rearing were done in rearing tanks. Growth of young top shell in the nursing ground were also investigated. For induced spawning, top shells were maintained in still water during night time. Then they were treated with ultra violet iradiated sea water after dried up in air for 60 minutes. Spawning rate were 10 to $39.77\%$. It was found that young top shells moved in the growing grounds from nursing grounds when they reached approximately 30-40mm in shell heignt. Among main food algae for top shell in the natural growing grounds, sea mustard were melted away during June. Therefore, presence of another food algae such as Ecklonia cava or Sargassum spp. seems to be the main limiting factor for survival of top shell during summer. The tolerance of top shells ranging from 30mm to 60mm to low density of seawater for were tested at the temperature between 29.5 and $31.4^{\circ}C$. Hundred percent mortality occoured in 20, 55 and 90 hours after first stocking at the specific gravity of 1.010, 1.015, and 1.020, respectively.