• The Korean Journal of Ecology
• /
• v.22 no.3
• /
• pp.163-167
• /
• 1999

In order to investigate territorial behaviour, Pungitius sinensis kaibarae were collected from Sacheon-river, Kangwon-do, Korea. They are reared in aquarium with designed experimental region from March to May 1996. In this study, territorial behaviour was divided into 1) pre-territorial movements of a shoal under varying water-weeds position 2) individual ranking patterns in connection with total length of fish 3) the change in size of territorial maps during the parental stage. The movements of a shoal tend to prefer regions with water-weeds and the lower half of the aquarium. Competition for territory was fierce, and fish that are longer in total length dominate smaller one in occupying territory. Both males and females developed territorial behaviour as they grew. However, male's territory was enlarged according to the hatching and dispersion of fry. At this time, aggressive tendencies reached their peak.

• Journal of the Korea Society for Simulation
• /
• v.21 no.2
• /
• pp.1-9
• /
• 2012

Subterranean termites forage by constructing tunnel networks in soil and encounter food resources during tunnel excavation. Some species of termites can travel up to 150 m underground. They often travel to the surface to find wood cellulose to feed their colony, which in turn causes extensive damage to wooden architecture, such as timber-frame houses. This type of damage has been constantly increasing along with global warming because higher temperatures provide an ecological niche for termites. The damage is closely related to termite territory size and distribution. Recently, as a way to research termite control, the necessity of a mathematical model to simulate termite territory formation in relation to damage has increased. So far, however, few studies have been conducted on the development of a model because it is difficult to quantify or characterize the relationship between territorial behavior and field conditions including complicated environmental factors. In the present study, we suggest a simulation model of the territoriality of the Formosan subterranean termites, Coptotermes formosanus (Shiraki), and Reticulitermes flavipes (Kollar), based on empirical data. The model consists of 2 procedures. One describes tunnel network growth for each colony, and the other represents territoriality based on tunnel-tunnel interactions between different colonies. Using the model, we show changes in territorial competition according to the termination probability of tunnel growth.

• Journal of Ecology and Environment
• /
• v.31 no.1
• /
• pp.17-21
• /
• 2008

Mating behaviour of the gammarid amphipod, Hyale rubra, was observed. H. rubra displayed precopulatory mate guarding: males clasped females with their gnathopods during copulation, forming a pair. Males also participated in embryo care during the incubation period. The population was small, and the sex ratio was almost equal. Energy allocation for mating effort and parental effort in the two sexes appear to be almost equal. The mating system was sequentially polygamous (or promiscuous) and there was conspicuous sexual dimorphism in the size of the gnathopod, which was used for mate guarding. However, there appears to be relatively weak sexual competition for mating opportunities despite conspicuous sexual dimorphism. H. rubra did not display territorial competition or external fertilization. Nevertheless, the male provided paternal care. Since H. rubra inhabit tide pools and live on algae, the polygamous mating system of the species can be explained by the polygyny threshold model. The evolution of mate guarding and parental care may have been favored by the species' low population density and harsh environments, an interpretation consistent with the optimality model.

• Strategy21
• /
• s.42
• /
• pp.154-195
• /
• 2017

This paper is to analyse conflict between the US and China over the South China Sea and Korea's responses. To this end the paper is composed of 6 chapters titled instruction; the current status of South China Sea sovereignty disputes; changes in US and Chinese maritime security strategies and the strategic values of the South China Sea; key issues and future prospects for US-China conflicts in the South China Sea; South Korea's security and diplomatic responses; and conclusion. The recent East Asian maritime security issue has evolved into a global issue of supremacy between the US and China, beyond conflicts over territorial disputes and demarcation among the countries in the region. China is pursuing offensive ocean policy to expand economic growth. The core of the maritime order that the United States intends to pursue is the freedom of navigation in the oceans and the maintenance of maritime access. China is making artificial islands in the South China Sea, claiming the sovereignty of these islands, building strategic bases in East Asia, and securing routes. The United States has developed several "Freedom of Navigation Operations" to neutralize the declaration of the territorial sea surrounding Chinese artificial islands. We can not be free from marine conflicts in the South China Sea and the East China Sea. Regarding the South China Sea dispute, it is expected that the strategic competition and conflict between the two countries will intensify due to China's failure to make concessions of core interests and adherence to the US compliance with international norms. In the midst of conflict over the South China Sea, we need a harmonious balance between our alliance security and economic diplomacy. We must continue our efforts to strengthen the ROK-US alliance but not to make China an enemy. Considering the significant impacts of the oceans on the survival and prosperity of the nation, we must continue to develop our interest in the oceans, appropriate investments and tactical strategies.

• Animal cells and systems
• /
• v.13 no.1
• /
• pp.91-96
• /
• 2009

The size of song repertoires mainly provides evidence for explaining sexual selection for female choice as well as male-male competition. We investigated the role of oriental great reed warbler songs (Acrocephalus orientalis) of breeding territorial males. Early arrived males possessed larger song repertoires, paired earlier, and tended to become polygynous. No correlation was found between arrival date and territory size, but polygynous males significantly occupied larger territories than non polygynous males. Song sharing was low among males and the degree of similarity did not relate with spatial distance. Our results suggest that song repertoire of the oriental great reed warbler males play a role in female choice, where territory quality may affect male pairing success.

• Strategy21
• /
• s.43
• /
• pp.175-199
• /
• 2018

Recent marine territorial disputes in the East China Sea and the South China Sea have come to us as a great threat. China, which has recently established the China Coast Guard and has rapidly developed maritime security forces, is trying to overcome the various conflict countries with its power. Japan is also strengthening intensively its maritime security forces. Since Korea, China, and Japan are geographically neighboring and sharing maritime space in Northeast Asia, there is no conflict between maritime jurisdiction and territorial rights among the countries. The struggle for initiative in the ocean is fierce among the three coastal nations in Northeast Asia. therefore, Korea needs more thorough preparation and response to protect the marine sovereignty. As the superpowers of China and Japan are confronted and the United States is involved in the balance of power in strategic purposes, the East Asian sea area is a place where tension and conflict environment exist. China's illegal fishing boats are constantly invading our waters, and they even threaten the lives of our police officers. The issue of delimiting maritime boundaries between Korea and China has yet to be solved, and is underway in both countries, and there is a possibility that the exploration activities of the continental shelf resources may collide as the agreement on the continental shelf will expire between Korea and Japan. On the other hand, conflicts in the maritime jurisdictions of the three countries in Korea, China and Japan are leading to the enhancement of maritime security forces to secure deterrence rather than military confrontation. In the situation where the unresolved sovereignty and jurisdiction conflicts of Korea, China and Japan continue, and the competition for the strengthening of the maritime powers of China and Japan becomes fierce, there is a urgent need for stabilization and enhancement of the maritime forces in our country. It is necessary to establish a new long-term strategy for enhancing the maritime security force and to carry out it. It is expected that the Korean Coast Guard, which once said that it was a model for the establishment of China's Coast Guard as a powerful force for the enforcement of the maritime law, firmly establishes itself as a key force to protect our oceans with the Navy and keeps our maritime sovereignty firmly.

• Journal of Fisheries and Marine Sciences Education
• /
• v.28 no.6
• /
• pp.1549-1560
• /
• 2016

Today, all the countries of the world newly recognize importance of sea, which are focused on efforts for security of marine territory and fishes resources. Many of the coastal state, to strengthen the rights of their own country EEZ, marine survey and continental shelf development, travels through such maritime jurisdiction in the territorial sovereignty and the EEZ overlaps, deepening complex interests between neighboring countries cooperation activities of the fierce competition, the domestic and foreign been has been carried out. Under such circumstances, is devastated coastal of China, our territorial waters and EEZ has been violated more and more, in spite of the powerful crackdown maritime public power, illegal fishing more resistance intensified. They tend to be gradually organization, collectivization and atrocities. Currently, illegal fishing of Chinese fishing boats in the West Sea of Korea, including the waters near Yeonpyeong Island is prevalent as operating in the coast of the country. Furthermore regrettable one is illegal on a scale and the situation where South Korea of scale of damage caused by it have not been accurately grasp of the operation, but that there is damage of Korea official duty enforcement to crack down the increase to illegal operations year after year have occurred. Violent, illegal fishing of Chinese fishing boats, in order to eradicate the operations of insane at our sea, we investigated to the infringement situations of fisheries resources by multiple fields. each of problems presenting a specific preservation plan in accordance with the function and role of the maritime enforcement organization and other government organization the point. at the same time we will try to seek measures such as a scheme that it is possible to increase the capacity.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.4
• /
• pp.769-788
• /
• 2014

Today, all the countries of the world newly recognize importance of sea on 70% area of the earth, which are focused on efforts for security of marine territory and fishes resources. On the security concerns of the ocean & fishes resources, Sea are very important on the ground of the importance of the ocean, thus international community has been trying to combat a maritime security threat and illegal fisheries. Coastal states need to have proper state's jurisdiction and exercise it's jurisdiction to response effectively to a maritime security threat and illegal fisheries. Here, many of the coastal states strengthened the rights in Exclusive Economic Zone(;EEZ) naturally, there are made cooperation activities and keen competition in the sea because deepening of complex understanding of the relationship between the surrounding countries with marine surveys & continental shelf development, island territorial sovereignty & marine jurisdiction in overlap of sea area on EEZ. In these circumstances, foreign fishing boats invaded to our territorial waters and EEZ many times. in addition, Chinese fishing boats are going to illegal fisheries naturally. On this point, a powerful crackdown of maritime enforcement organization had no effect on them. Also more and more their resistance gathered strength and tendency of a illegal activities became systematization, group action and atrocity little by little. So this thesis includes a study on the regal regulation, the system and formalities on the control of illegal fishing. And the author analyzed the details of the activities of illegal fishing and boats controlled by Korea Coast Guard(KCG), fishing patrol vessels of Ministry of Maritime Affaires and Fisheries(MOMAF) and Navy etc. from in adjacent sea area of Korea. In relation to this, the policy and activity plan were devised to crackdown to illegal fisheries of foreign fishing boats and then it was enforced every year. According to this, analyze the present conditions of illegal fisheries of a foreign fishing boats on this study, also analyze the present conditions of maritime enforcement organization & found out problems to compared it. protect the territorial waters, at the same time protection of marine mineral resources & fishes resources of EEZ including continental shelf, which has want to study for the role & response of maritime enforcement organization for the protection of fisheries resources and a proper, a realistic confrontation plan of maritime enforcement organization against illegal fisheries of foreign fishing boats.

• The Korean Journal of Ecology
• /
• v.27 no.6 s.122
• /
• pp.383-390
• /
• 2004

This study was conducted in three sites, Si-Hwa Lake, Dongman and Seoman island and Janguyeop island, from march, 1999 to september, 2002. The behaviors of pre-breeding season, territorial behaviors, reproductive ecology, foraging sites and behaviors, and the competition of reproduction and foods between intraspecific or interspecific of Eurasian Oystercatcher (Haematopus ostralegus) were observed in each studying sites. The breeding of Eurasian Oystercatcher started on the middle of April in Si-Hwa Lake and on the middle of May in Dongman and Seoman island and Janguyeop island. For intension of pair bond on pre-breeding season, Eurasian Oystercatcher foraged with pair and behaved male-female chasing flight behavior. The pair foraged with male and female before copulation. If other pairs and individuals approached in feeding site of pair, this pair attacked them with piping calling and intruder chasing flight. If continuos serial behaviors were not observed, the discrimination of male-female chasing flight and intruder chasing flight was difficult. Territorial behaviors classified four types; butterfly flight, calling behavior, chasing behavior, fight behavior. The important foraging sites in Si-Hwa Lake are the land place in Daeboo island, tidal flat of Bangameori, tidal flat a front of a stationary net for catching fishes and tidal flat a front of a view station for bird watching. Eurasian Oystercatcher foraged at tidal flat on low water of the tide and foraged at feeding sites near island on flood tide in Dongman and Seoman island. Eurasian Oystercater in Janguyeop island usually foraged feeding sites near island, because water level was not different between low water of the tide and flood tide. Eurasian Oystercatcher competed on foods of intraspecific and interspecific. They chased for taking foods by force in feeding sites and drove out intruders in feeding sites. The foods interspecific competition happened with Black-tailed Gull (Larus crassirostris). Eurasian Oystercatcher was robbed of foods and attacked by Black-tailed Gull. The individual of food competition with Black-tailed Gull was low foods intake rate comparison with other feeding sites and this individual flied out other feeding sites.

• Journal of Digital Convergence
• /
• v.11 no.6
• /
• pp.43-55
• /
• 2013

This study was to examine the operation strategy of terrestrial broadcasting system on channel image and N-screen service. Nowadays, terrestrial broadcasting system provides video streaming service based on internet. In other words, terrestrial broadcasting system provides N-screen service through TV-PC-Smart phone-Tablet PC. But it is different for terrestrial broadcasting system to analysis the choice criterion of program. Only, channel image of terrestrial broadcasting system expanded into N-screen. Finally, channel image of terrestrial broadcasting system is the competition strategy. It is necessary for terrestrial broadcasting system to prepare the strategy of program choice for users, original contents, new platform and service in connection with N-screen.